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The domestication of animals marks a pivotal moment in human history, profoundly influencing our demographic and cultural progress. This process has led to significant genetic, behavioral, and physical changes in livestock species compared to their wild ancestors. Understanding the evolutionary history and genetic diversity of livestock species is crucial, and mitochondrial DNA (mtDNA) has emerged as a robust marker for investigating molecular diversity in animals. Its highly conserved gene content across animal species, minimal duplications, absence of introns, and short intergenic regions make mtDNA analysis ideal for such studies. Mitochondrial DNA analysis has uncovered distinct cattle domestication events dating back to 8000 years BC in Southwestern Asia. The sequencing of water buffalo mtDNA in 2004 provided important insights into their domestication history. Caprine mtDNA analysis identified three haplogroups, indicating varied maternal origins. Sheep, domesticated 12,000 years ago, exhibit diverse mtDNA lineages, suggesting multiple domestication events. Ovine mtDNA studies revealed clades A, B, C, and a fourth lineage, group D. The origins of domestic pigs were traced to separate European and Asian events followed by interbreeding. In camels, mtDNA elucidated the phylogeographic structure and genetic differentiation between wild and domesticated species. Horses, domesticated around 3500 BC, show significant mtDNA variability, highlighting their diverse origins. Yaks exhibit unique adaptations for high-altitude environments, with mtDNA analysis providing insights into their adaptation. Chicken mtDNA studies supported a monophyletic origin from Southeast Asia's red jungle fowl, with evidence of multiple origins. This review explores livestock evolution and diversity through mtDNA studies, focusing on cattle, water buffalo, goat, sheep, pig, camel, horse, yak and chicken. It highlights mtDNA's significance in unraveling maternal lineages, genetic diversity, and domestication histories, concluding with insights into its potential application in improving livestock production and reproduction dynamics., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Glaucoma is a sight threatening neurodegenerative condition of the optic nerve head associated with ageing and marked by the loss of retinal ganglion cells. Mitochondrial dysfunction plays a crucial role in the pathogenesis of neurodegeneration in the most prevalent type of glaucoma: primary open angle glaucoma (POAG). All previous mitochondrial genome sequencing studies in POAG analyzed mitochondrial DNA (mtDNA) isolated from peripheral blood leukocytes and have not evaluated cells derived from ocular tissue, which better represent the glaucomatous disease context. In this study, we evaluated mitochondrial genome variation and heteroplasmy using massively parallel sequencing of mtDNA in a cohort of patients with POAG, and in a subset assess the role of somatic mitochondrial genome mutations in disease pathogenesis using paired samples of peripheral blood leukocytes and ocular tissue (Tenon's ocular fibroblasts). An enrichment of potentially pathogenic nonsynonymous mtDNA variants was identified in Tenon's ocular fibroblasts from participants with POAG. The absence of oxidative DNA damage and predominance of transition variants support the concept that errors in mtDNA replication represent the predominant mutation mechanism in Tenon's ocular fibroblasts from patients with POAG. Pathogenic somatic mitochondrial genome mutations were observed in people with POAG. This supports the role of somatic mitochondrial genome variants in the etiology of glaucoma., (© 2024. The Author(s).)

Arsenic is a toxic element that can cause severe liver damage in humans and animals. Arsenic-based inorganic pesticides, such as lead arsenate, copper arsenate, and calcium arsenate, are widely used for insect control and can eventually affect human health through accumulation in the food chain. However, the relationship between arsenic trioxide (ATO)-induced hepatotoxicity and the cGAS-STING signaling pathway has not been reported. The aim of this study was to investigate the potential role of inflammatory response in ATO-induced hepatotoxicity in chickens. In this study, we found that ATO exposure resulted in mtDNA leakage into the cytoplasm of chicken hepatocytes, which activated the cGAS-STING pathway and significantly increased the cGAS, STING, TBK1, and IRF7 mRNA and protein expression levels. Moreover, type I interferon response was activated. Concurrently, STING triggered the activation of the traditional NF-κB signaling pathway and promoted the expression of pro-inflammatory cytokine genes, including TNF-α, IL-6, and IL-1β. Subsequently, we found that both mtDNA clearance with EtBr and inhibition of the cGAS-STING pathway with H-151 reversed the ATO-induced innate immune and inflammatory responses. In summary, the above findings indicate that chicken hepatocytes can induce innate immune responses and inflammatory responses via mtDNA-cGAS-STING under ATO-exposure conditions, which is of great significance for further studies on the toxicity mechanism of ATO., Competing Interests: Declaration of competing interest We declare that there is no conflict of interest in this work., (Copyright © 2024. Published by Elsevier Inc.)

Leber's hereditary optic neuropathy (LHON) is a debilitating mitochondrial disease associated with mutations in mitochondrial DNA (mtDNA). Unfortunately, the available treatment options for LHON patients are limited due to challenges in mitochondrial replacement. In our study, we reprogramming LHON urine cells into induced pluripotent stem cells (iPSCs) and differentiating them into neural progenitor cells (NPCs) and neurons for disease modeling. Our research revealed that LHON neurons exhibited significantly higher levels of mtDNA mutations and reduced mitochondrial function, confirming the disease phenotype. However, through co-culturing LHON iPSC-derived NPCs with mesenchymal stem cells (MSCs), we observed a remarkable rescue of mutant mtDNA and a significant improvement in mitochondrial metabolic function in LHON neurons. These findings suggest that co-culturing with MSCs can enhance mitochondrial function in LHON NPCs, even after their differentiation into neurons. This discovery holds promise as a potential therapeutic strategy for LHON patients., (© 2024. Science China Press.)

Background: UV-A radiation contributes to photoaging/photocarcinogenesis by generating inflammation and oxidative damage. Current photoprotective strategies are limited by the availability/utilization of UV-A filters, highlighting an unmet need. Cannabidiol (CBD), having anti-inflammatory/antioxidant properties via regulation of nuclear erythroid 2-related factor, heme oxygenase 1, and peroxisome proliferator-activated receptor gamma, could potentially mitigate damage from UV-A exposure., Objective/methods: This is a prospective, single-center, pilot clinical trial (NCT05279495). Nineteen participants applied nano-CBD (nCBD) or vehicle (VC) cream to randomized, blinded buttock sites twice daily for 14 days; then, the treated sites were irradiated with ≤3× UV-A minimal erythema dose. After 24 hours, punch biopsies were obtained for histology, immunohistochemistry, and real-time polymerase chain reaction., Results: At 24 hours, 21% of participants had less observed erythema on CBD-treated skin than on VC skin. Histologically, nCBD-treated skin had reduced UV-A-induced epidermal hyperplasia than VC (P = .01). Immunohistochemistry detected reduced cytoplasmic/nuclear 8-oxoguanine glycosylase 1 staining in nCBD-treated skin compared with VC (P < .01). Quantitative mtDNA polymerase chain reaction demonstrated that UV-A-induced deletion of ND4 (proxy:4977 bp deletion; P = .003) and ND1 (proxy:3895 bp deletion; P = .002) was significantly reduced by in vivo nCBD treatment compared with VC., Limitations: Small sample size is this study's limitation., Conclusion: Topically applied nCBD cream reduced UV-A-induced formation of a frequent mutagenic nuclear DNA base lesion and protected against mtDNA mutations associated with UV-A-induced skin aging. To our knowledge, this trial is the first to identify UV-protective capacity of CBD-containing topicals in humans., Competing Interests: Conflicts of interest McCormick, Han, Azim, Whiting, Bhamidipati, Kiss, and Efimova have no conflicts to disclose. Friedman is a coinventor of nanoparticle technology. Berman is a consultant for Mino Labs., (Copyright © 2024 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.)

Mitochondrial DNA (mtDNA) G-quadruplexes (G4s) have important regulatory roles in energy metabolism, yet their specific functions and underlying regulatory mechanisms have not been delineated. Using a chemical-genetic screening strategy, we demonstrated that the JAK/STAT3 pathway is the primary regulatory mechanism governing mtDNA G4 dynamics in hypoxic cancer cells. Further proteomic analysis showed that activation of the JAK/STAT3 pathway facilitates the translocation of RelA, a member of the NF-κB family, to the mitochondria, where RelA binds to mtDNA G4s and promotes their folding, resulting in increased mtDNA instability, inhibited mtDNA transcription, and subsequent mitochondrial dysfunction. This binding event disrupts the equilibrium of energy metabolism, catalyzing a metabolic shift favoring glycolysis. Collectively, the results provide insights into a strategy employed by cancer cells to adapt to hypoxia through metabolic reprogramming., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Brain functions are mediated via the complex interplay between several complex factors, and hence, identifying the underlying cause of an abnormality within a certain brain region can be challenging. In mitochondrial disease, abnormalities in brain function are thought to be attributed to accumulation of mitochondrial DNA (mtDNA) with pathogenic mutations; however, only few previous studies have directly demonstrated that accumulation of mutant mtDNA induced abnormalities in brain function. Herein, we examined the effects of mtDNA mutations on brain function via behavioral analyses using a mouse model with an A2748G point mutation in mtDNA tRNA Leu(UUR) . Our results revealed that mice with a high percentage of mutant mtDNA showed a characteristic trend toward reduced prepulse inhibition and memory-dependent test performance, similar to that observed in psychiatric disorders, such as schizophrenia; however, muscle strength and motor coordination were not markedly affected. Upon examining the hippocampus and frontal lobes of the brain, mitochondrial morphology was abnormal, and the brain weight was slightly reduced. These results indicate that the predominant accumulation of a point mutation in the tRNA Leu(UUR) gene may affect brain functions, particularly the coordination of sensory and motor functions and memory processes. These abnormalities probably caused by both direct effects of accumulation of the mutant mtDNA in neuronal cells and indirect effects via changes of systemic extracellular environments. Overall, these findings will lead to a better understanding of the pathogenic mechanism underlying this complex disease and facilitate the development of optimal treatment methods., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Kaori Ishikawa reports financial support was provided by Japan Science and Technology Agency. Kaori Ishikawa, Kazuto Nakada reports financial support was provided by Japan Society for the Promotion of Science. Kazuto Nakada reports financial support was provided by Japan Agency for Medical Research and Development. Tsuyoshi Miyakawa reports financial support was provided by Government of Japan Ministry of Education Culture Sports Science and Technology. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Mitochondrial disorders are a class of heterogeneous disorders caused by genetic variations in the mitochondrial genome (mtDNA) as well as the nuclear genome. The spectrum of mtDNA variants remains unexplored in the Indian population. In the present study, we have cataloged 2689 high confidence single nucleotide variants, small insertions and deletions in mtDNA in 1029 healthy Indian individuals. We found a major proportion (76.5 %) of the variants being rare (AF<=0.005) in the studied population. Intriguingly, we found two 'confirmed' pathogenic variants (m.1555 A>G and m.14484 T>C) with a frequency of ∼1 in 250 individuals in our dataset. The high carrier frequency underscores the need for screening of the mtDNA pathogenic mutations in newborns in India. Interestingly, our analysis also revealed 202 variants in our dataset which have been 'reported' in disease cases as per the MITOMAP database. Additionally, we found the frequency of haplogroup M (52.2 %) to be the highest among all the 18 top-level haplogroups found in our dataset. In comparison to the global population datasets, 20 unique mtDNA variants are found in the Indian population. We hope the whole genome sequencing based compendium of mtDNA variants along with their allele frequencies and heteroplasmy levels in the Indian population will drive additional genome scale studies for mtDNA. Furthermore, the identification of clinically relevant variants in our dataset will aid in better clinical interpretation of the variants in mitochondrial disorders., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: Disrupted cellular communication, inflammatory responses and mitochondrial dysfunction are consistently observed in late-life depression (LLD). Exosomes (EXs) mediate cellular communication by transporting molecules, including mitochondrial DNA (EX-mtDNA), playing critical role in immunoregulation alongside tumor necrosis factor (TNF). Changes in EX-mtDNA are indicators of impaired mitochondrial function and might increase vulnerability to adverse health outcomes. Our study examined EX-mtDNA levels and integrity, exploring their associations with levels of TNF receptors I and II (TNFRI and TNFRII), and clinical outcomes in LLD., Methods: Ninety older adults (50 LLD and 40 controls (HC)) participated in the study. Blood was collected and exosomes were isolated using size-exclusion chromatography. DNA was extracted and EX-mtDNA levels and deletion were assessed using qPCR. Plasma TNFRI and TNFRII levels were quantified by multiplex immunoassay. Correlation analysis explored relationships between EX-mtDNA, clinical outcomes, and inflammatory markers., Results: Although no differences were observed in EX-mtDNA levels between groups, elevated levels correlated with poorer cognitive performance (r = -0.328, p = 0.002) and increased TNFRII levels (r = 0.367, p = 0.004). LLD exhibited higher deletion rates (F (83,1)  = 4.402, p = 0.039), with a trend remaining after adjusting for covariates (p = 0.084). Deletion correlated with poorer cognitive performance (r = -0.335, p = 0.002). No other associations were found., Limitation: Cross-sectional study with a small number of participants from a specialized geriatric psychiatry treatment center., Conclusion: Our findings suggest that EX-mtDNA holds promise as an indicator of cognitive outcomes in LLD. Additional research is needed to further comprehend the role of EX-mtDNA levels/integrity in LLD, paving the way for its clinical application in the future., Competing Interests: Declaration of competing interest Dr. James L. Kennedy is a member of the Scientific Advisory Board of Myriad Neuroscience (unpaid) and holds several patents relating to pharmacogenetic tests for psychiatric medications. Dr. Tarek K. Rajji has received research support from Brain Canada, Brain and Behavior Research Foundation, BrightFocus Foundation, Canada Foundation for Innovation, Canada Research Chair, Canadian Institutes of Health Research, Centre for Aging and Brain Health Innovation, National Institutes of Health, Ontario Ministry of Health and Long-Term Care, Ontario Ministry of Research and Innovation, and the Weston Brain Institute. Dr. Rajji also received for an investigator-initiated study in-kind equipment support from Newronika, and in-kind research online accounts from Scientific Brain Training Pro, and participated in 2021 and 2022 in an advisory activity for Biogen Canada Inc. Dr. Rajji is also an inventor on the United States Provisional Patent No. 17/396,030 that describes cell-based assays and kits for assessing serum cholinergic receptor activity. Dr. Diniz receives research support from the US National Institute of Health (NIH). All other authors report no conflict of interest related to this study., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Modern humans have experienced explosive population growth in the past thousand years. We hypothesized that recent human populations have inhabited environments with relaxation of selective constraints, possibly due to the more abundant food supply after the Last Glacial Maximum. The ratio of nonsynonymous to synonymous mutations (N/S ratio) is a useful and common statistic for measuring selective constraints. In this study, we reconstructed a high-resolution phylogenetic tree using a total of 26,419 East Eurasian mitochondrial DNA genomes, which were further classified into expansion and nonexpansion groups on the basis of the frequencies of their founder lineages. We observed a much higher N/S ratio in the expansion group, especially for nonsynonymous mutations with moderately deleterious effects, indicating a weaker effect of purifying selection in the expanded clades. However, this observation on N/S ratio was unlikely in computer simulations where all individuals were under the same selective constraints. Thus, we argue that the expanded populations were subjected to weaker selective constraints than the nonexpanded populations were. The mildly deleterious mutations were retained during population expansion, which could have a profound impact on present-day disease patterns., (© The Author(s) 2024. Published by Oxford University Press on behalf of Society for Molecular Biology and Evolution.)

Mitochondrial health is an integral factor in aging, with mitochondrial dysfunction known to increase with age and contribute to the development of age-related neurodegenerative disorders. Additionally, the mitochondrial genome (mtDNA) has been shown to acquire potentially damaging somatic variation as part of the aging process, while mtDNA single nucleotide polymorphism (SNPs) have been shown to be both protective and detrimental for various neurodegenerative diseases. Yet, little is known about the involvement of mtDNA variation in longevity and successful neurological aging. In this study, we examined the association of mtDNA SNPs, in the form of mitochondrial haplogroups, with successful neurological aging in 1,405 unrelated neurologically healthy subjects. Although not quite significant after correcting for multiple testing (P < 0.0017 considered as significant), we detected a nominally significant association between the I haplogroup (N = 45, 3.2 %) and a younger age (β: -5.00, P = 0.006), indicating that this haplogroup is observed less frequently in older neurologically healthy individuals and may be associated with decreased survival. Replication of this finding in independent neurologically healthy cohorts will be imperative for shaping our understanding of the biological processes underlying healthy neurological aging., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: O.A.R.: Consulted for SciNeuro and received support from National Institute of Health/National Institute of Neurological Disorders and Stroke (NIH/NINDS) [R01 NS085070, R01 NS078086, U54-NS100693 and U54 NS110435], the Department of Defense Congressionally Directed Medical Research Programs (CDMRP) [W81XWH-17-1-0249], the Michael J. Fox Foundation for Parkinson’s Research (MJFF), the American Parkinson Disease Association (APDA), and American Brain Foundation. ZKW is partially supported by the NIH/NIA and NIH/NINDS (1U19AG063911, FAIN: U19AG063911), Mayo Clinic Center for Regenerative Medicine, the gifts from the Donald G. and Jodi P. Heeringa Family, the Haworth Family Professorship in Neurodegenerative Diseases fund, and The Albertson Parkinson's Research Foundation. He serves as PI or Co-PI on Biohaven Pharmaceuticals, Inc. (BHV4157-206) and Vigil Neuroscience, Inc.(VGL101-01.002, VGL101-01.201, PET tracer development protocol, Csf1r biomarker and repository project, and ultra-high field MRI in the diagnosis and management of CSF1R-related adult-onset leukoencephalopathy with axonal spheroids and pigmented glia) projects/grants. He serves as Co-PI of the Mayo Clinic APDA Center for Advanced Research and as an external advisory board member for the Vigil Neuroscience, Inc., and as a consultant on neurodegenerative medical research for Eli Lilli & Company., (Copyright © 2024. Published by Elsevier B.V.)

Type-1 IFN (interferon)-associated innate immune response is increasingly getting attention in neurodegenerative and metabolic diseases like type 2 diabetes (T2DM). However, its significance in T2DM/lipotoxicity-induced neuroglia changes and cognitive impairment is missing. The present study aims to evaluate the involvement of cGAS (cyclic GMP-AMP synthase)-STING (stimulator of interferon gene), IRF3 (interferon regulatory factor-3), TBK (TANK binding kinase)-mediated Type-1 IFN response in the diabetic brain, and lipotoxicity (palmitate-bovine serum albumin conjugate/PA-BSA)-induced changes in cells (neuro2a and BV2). T2DM was induced in C57/BL6 mice by feeding on a high-fat diet (HFD, 60% Kcal) for 16 weeks and injecting a single dose of streptozotocin (100 mg/kg, i.p) in the 12th week. Plasma biochemical parameter analysis, neurobehavioral assessment, protein expression, and quantitative polymerase chain reaction study were carried out to decipher the hypothesis. T2DM-associated metabolic and lipotoxic stress led to mitochondrial impairment causing leakage of mtDNA to the cytoplasm further commencing cGAS activation and its downstream signaling. The diseased hippocampus and cortex showed decreased expression of synaptophysin (p < 0.01) and PSD-95 (p < 0.01, p < 0.05) with increased expression of cGAS (p < 0.001), p-STING (p < 0.001), p-STAT1 (signal transducer and activator of transcription) (p < 0.01), and IFN-β (p < 0.001) compared to normal control. The IFN-β/p-STAT1-mediated microglia activation was executed employing a conditioned media approach. C-176, a selective STING inhibitor, alleviated cGAS/p-STING/IFN-β expression and proinflammatory microglia/M1-associated markers (CD16 expression, CXCL10, TNF-α, IL-1β mRNA fold change) in the diabetic brain. The present study suggests Type-1IFN response may result in neuroglia dyshomeostasis affecting normal brain function. Alleviating STING signaling has the potential to protect T2DM-associated central ailment., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Post-mitotic, non-proliferative dermal fibroblasts have crucial functions in maintenance and restoration of tissue homeostasis. They are involved in essential processes such as wound healing, pigmentation and hair growth, but also tumor development and aging-associated diseases. These processes are energetically highly demanding and error prone when mitochondrial damage occurs. However, mitochondrial function in fibroblasts and the influence of mitochondrial dysfunction on fibroblast-specific demands are still unclear. To address these questions, we created a mouse model in which accelerated cell-specific mitochondrial DNA (mtDNA) damage accumulates. We crossed mice carrying a dominant-negative mutant of the mitochondrial replicative helicase Twinkle (RosaSTOP system) with mice that express fibroblast-specific Cre Recombinase (Collagen1A2 Cre ERT ) which can be activated by Tamoxifen (Twinkle FIBRO ). Thus, we are able to induce mtDNA deletions and duplications in specific cells, a process which resembles the physiological aging process in humans, where this damage accumulates in all tissues. Upon proliferation in vitro, Tamoxifen induced Twinkle fibroblasts deplete most of their mitochondrial DNA which, although not disturbing the stoichiometry of the respiratory chain complexes, leads to reduced ROS production and mitochondrial membrane potential as well as an anti-inflammatory and anti-fibrotic profile of the cells. In Sodium Azide treated wildtype fibroblasts, without a functioning respiratory chain, we observe the opposite, a rather pro-inflammatory and pro-fibrotic signature. Upon accumulation of mitochondrial DNA mutations in vivo the Twinkle FIBRO mice are protected from fibrosis development induced by intradermal Bleomycin injections. This is due to dampened differentiation of the dermal fibroblasts into α-smooth-muscle-actin positive myofibroblasts in Twinkle FIBRO mice. We thus provide evidence for striking differences of the impact that mtDNA mutations have in contrast to blunted mitochondrial function in dermal fibroblasts and skin homeostasis. These data contribute to improved understanding of mitochondrial function and dysfunction in skin and provide mechanistic insight into potential targets to treat skin fibrosis in the future., (Copyright © 2024. Published by Elsevier B.V.)

In diabetic retinopathy, mitochondrial DNA (mtDNA) is damaged and mtDNA-encoded genes and long noncoding RNA cytochrome B (LncCytB) are downregulated. LncRNAs lack an open reading frame, but they can regulate gene expression by associating with DNA/RNA/protein. Double stranded mtDNA has promoters on both heavy (HSP) and light (LSP) strands with binding sites for mitochondrial transcription factor A (TFAM) between them. The aim was to investigate the role of LncCytB in mtDNA transcription in diabetic retinopathy. Using human retinal endothelial cells incubated in high glucose, the effect of regulation of LncCytB on TFAM binding at mtDNA promoters was investigated by Chromatin immunoprecipitation, and binding of LncCytB at TFAM by RNA immunoprecipitation and RNA fluorescence in situ hybridization. High glucose decreased TFAM binding at both HSP and LSP, and binding of LncCytB at TFAM. While LncCytB overexpression ameliorated decrease in TFAM binding and transcription of genes encoded by both H- and L- strands, LncCytB-siRNA further downregulated them. Maintenance of mitochondrial homeostasis by overexpressing mitochondrial superoxide dismutase or Sirtuin-1 protected diabetes-induced decrease in TFAM binding at mtDNA and LncCytB binding at TFAM, and mtDNA transcription. Similar results were obtained from mouse retinal microvessels from streptozotocin-induced diabetic mice. Thus, LncCytB facilitates recruitment of TFAM at HSP and LSP, and its downregulation in diabetes compromises the binding, resulting in the downregulation of polypeptides encoded by mtDNA. Regulation of LncCytB, in addition to protecting mitochondrial genomic stability, should also help in maintaining the transcription of mtDNA encoded genes and electron transport chain integrity in diabetic retinopathy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. and Mitochondria Research Society. All rights reserved.)

An established technology to create cloned animals is through the use of somatic cell nuclear transfer (SCNT), in which reprogramming the somatic cell nucleus to a totipotent state by enucleated oocyte cytoplasm is a necessary process, including telomere length reprogramming. The limitation of this technology; however, is that the live birth rate of offspring produced through SCNT is significantly lower than that of IVF. Whether and how telomere length play a role in the development of cloned animals is not well understood. Only a few studies have evaluated this association in cloned mice, and fewer still in cloned cows. In this study, we investigated the difference in telomere length as well as the abundance of some selected molecules between newborn deceased cloned calves and normal cows of different ages either produced by SCNT or via natural conception, in order to evaluate the association between telomere length and abnormal development of cloned cows. The absolute telomere length and relative mitochondrial DNA (mtDNA) copy number were determined by real-time quantitative PCR (qPCR), telomere related gene abundance by reverse-transcription quantitative PCR (RT-qPCR), and senescence-associated β-galactosidase (SA-β-gal) expression by SA-β-gal staining. The results demonstrate that the newborn deceased SCNT calves had significantly shortened telomere lengths compared to newborn naturally conceived calves and newborn normal SCNT calves. Significantly lower mtDNA copy number, and significantly lower relative abundance of LMNB1 and TERT, higher relative abundance of CDKN1A, and aberrant SA-β-gal expression were observed in the newborn deceased SCNT calves, consistent with the change in telomere length. These results demonstrate that abnormal telomere shortening, lower mtDNA copy number and abnormal abundance of related genes were specific to newborn deceased SCNT calves, suggesting that abnormally short telomere length may be associated with abnormal development in the cloned calves., Competing Interests: Declaration of competing interest All authors have no conflicts of interest to report., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Mitochondrial DNA copy number (mtDNA-CN) in human body fluids is widely used as a biomarker of mitochondrial dysfunction in common metabolic diseases. Here we describe protocols to measure cellular and/or cell free (cf)-mtDNA-CN in human peripheral blood and urine. Cellular mtDNA is located inside the mitochondria where it encodes key subunits of the respiratory complexes in mitochondria and is usually normalized with reference to the nuclear genome as the mitochondrial genome to nuclear genome ratio (Mt/N) in either whole blood, peripheral blood mononuclear cells (PBMCs), or whole urine. Cf -mtDNA is usually found outside of the mitochondria, often released following mitochondrial damage, can trigger inflammatory pathways, and is usually measured as mtDNA-CN per volume of the starting material. Here we describe how to (1) separate whole blood into PBMCs, plasma, and serum fractions and whole urine into urinary supernatant and pellet, (2) prepare DNA from each of these fractions, (3) prepare reference standards for absolute quantification, (4) carry out qPCR for either relative or absolute quantification from test samples, (5) analyze qPCR data, and (6) calculate the sample size to adequately power studies. The protocol presented here is suitable for high throughput use and can be modified to quantify mtDNA from other body fluids, human cells, and tissues., (© 2025. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Purpose of Review: This narrative review summarizes current literature on the relationship of mitochondrial biomarkers with obesity-related characteristics, including body mass index and body composition., Recent Findings: Mitochondria, as cellular powerhouses, play a pivotal role in energy production and the regulation of metabolic process. Altered mitochondrial functions contribute to obesity, yet evidence of the intricate relationship between mitochondrial dynamics and obesity-related outcomes in human population studies is scarce and warrants further attention. We discuss emerging evidence linking obesity and related health outcomes to impaired oxidative phosphorylation pathways, oxidative stress and mtDNA variants, copy number and methylation, all hallmark of suboptimal mitochondrial function. We also explore the influence of dietary interventions and metabolic and bariatric surgery procedures on restoring mitochondrial attributes of individuals with obesity. Finally, we report on the potential knowledge gaps in the mitochondrial dynamics for human health for future study., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Intracerebral hemorrhage (ICH) is a severe disease that often leads to disability and death. Neuroinflammatory response is a key causative factor of early secondary brain injury after ICH. AIM2 is a DNA-sensing protein that recognizes cytosolic double-stranded DNA and take a significant part in neuroinflammation. Mitochondrial DNA participates in the translation of proteins such as the respiratory chain in the mitochondria. Whether mtDNA is involved in forming AIM2 inflammasome after ICH remains unclear. We used mice to construct ICH model in vivo and we used BV2 microglial cells treated with oxyhemoglobin to simulate ICH in vitro. Following lentiviral transfection to overexpress AIM2 antagonist P202, a notable decrease was observed in the levels of AIM2 inflammasome-associated proteins, leading to a reduction in dead neurons surrounding the hematoma and an enhancement in long-term and short-term behavior of neurological deficits. We further explored whether mtDNA took part in the AIM2 activation after ICH. The cytosolic mtDNA level was down-regulated by the mitochondrial division protector Mdivi-1 and up-regulated by transfection of mtDNA into cytoplasm. We found the expression level of AIM2 inflammasome-related proteins and inflammatory cytokines release were regulated by the cytosolic mtDNA level. In conclusion, after ICH, the mtDNA content in the cytoplasm of microglia around the hematoma rises, causing AIM2 inflammation leading to neuronal apoptosis, which leads to neurological deficits in mice. On the other hand, P202 was able to block inflammatory vesicle activation and improve neurological function by preventing the interaction between AIM2 protein and mitochondrial DNA., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

We studied the association of mitochondrial DNA (mtDNA) haplogroups with weight and body mass index (BMI) gain at 96 weeks in 1019 treatment-naive persons with HIV (PWH) who initiated first-line antiretroviral therapy (ART) since 2014. The mean increase in weight and BMI over the study period was 2.90 kg and 0.98 kg/m2, respectively. We found a significant adjusted association between the major UK mtDNA haplogroup and lower weight and BMI increase at 96 weeks after ART initiation. Our findings reveal a potential role for mitochondrial genetics in the complex phenomenon of weight gain after initial ART in PWH., Competing Interests: Potential conflicts of interest. J. B. reports honoraria for advice or public speaking from Gilead, Glaxo Smith Kline (GSK), Janssen, Merck Sharp & Dohme (MSD), ViiV Healthcare; and grants from Gilead, MSD, and ViiV Healthcare. I. J. reports honoraria for advice or public speaking from Gilead and ViiV Healthcare; grants from MSD; and support for attending meetings and/or travel from Gilead. J. C. L. reports honoraria for advice or public speaking from Gilead, MSD, and ViiV Healthcare; grants from ViiV Healthcare; and support for attending meetings and/or travel from ViiV Healthcare and MSD. P. D. reports honoraria for advice or public speaking from Gilead, MSD, Janssen, and ViiV Healthcare. A. P.-M. reports honoraria for public speaking and support for attending meetings and/or travel from Gilead, MSD, Jannsen, and ViiV Healthcare. S. M. reports honoraria for advice or public speaking from Gilead, GSK, Janssen, MSD, and ViiV Healthcare; and grants from Gilead, MSD, and ViiV Healthcare. M. L. M. reports honoraria for advice or public speaking from AbbVie, BMS, Gilead, Jannsen, and ViiV Healthcare; and support for attending meetings and/or travel from ViiV Healthcare and Janssen. All other authors report no potential conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2024. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

This study aimed to comprehensively assess the metabolic, mitochondrial, and inflammatory effects of first-line efavirenz, emtricitabine, and tenofovir disoproxil fumarate (EFV/FTC/TDF) single-tablet regimen (STR) relative to untreated asymptomatic HIV infection. To this end, we analyzed 29 people with HIV (PWH) treated for at least one year with this regimen vs. 33 antiretroviral-naïve PWH. Excellent therapeutic activity was accompanied by significant alterations in metabolic parameters. The treatment group showed increased plasmatic levels of glucose, total cholesterol and its fractions (LDL and HDL), triglycerides, and hepatic enzymes (GGT, ALP); conversely, bilirubin levels (total and indirect fraction) decreased in the treated cohort. Mitochondrial performance was preserved overall and treatment administration even promoted the recovery of mitochondrial DNA (mtDNA) content depleted by the virus, although this was not accompanied by the recovery in some of their encoded proteins (since cytochrome c oxidase II was significantly decreased). Inflammatory profile (TNFα, IL-6), ameliorated after treatment in accordance with viral reduction and the recovery of TNFα levels correlated to mtDNA cell restoration. Thus, although this regimen causes subclinical metabolic alterations, its antiviral and anti-inflammatory properties may be associated with partial improvement in mitochondrial function.

The genetic identification of skeletal remains from Chinese People's Volunteers (CPVs) of the Korean War has been challenging because of the degraded DNA samples and the lack of living close relatives. This study established a workflow for identifying CPVs by combining Y-chromosome short tandem repeats (Y-STRs), mitochondrial DNA (mtDNA) hypervariable regions I and II, autosomal STRs (aSTRs), and identity-informative SNPs (iiSNPs). A total of 20 skeletal remains of CPVs and 46 samples from their alleged relatives were collected. The success rate of DNA extraction from human remains was 100%. Based on Y-STRs, six remains shared the same male lineages with their alleged relatives. Meanwhile, mtDNA genotyping supports two remains sharing the same maternal lineages with their alleged relatives. Likelihood ratios (LRs) were further obtained from 27 aSTRs and 94 iiSNPs or 1936 iiSNPs to confirm their relationship. All joint pedigree LRs were >100. Finally, six remains were successfully identified. This pilot study for the systematic genetic identification of CPVs from the Korean War can be applied for the large-scale identification of CPVs in the future., (© 2024 Wiley‐VCH GmbH.)

Background: Chemoresistance remains a significant challenge in colorectal cancer (CRC) treatment, necessitating a deeper understanding of its underlying mechanisms. HOXC11 has emerged as a potential regulator in various cancers, but its role in CRC chemoresistance remains unclear., Methods: Sulforhodamine B assay was employed to assess the cell viability of CRC cells following treatment with chemotherapeutic drugs. Immunofluorescence staining was performed to examine the subcellular localization of HOXC11 in normal and chemoresistant CRC cells. The Seahorse mito stress test was conducted to evaluate the mitochondrial respiratory function of CRC cells. Real-time PCR was utilized to measure the expression level and copy number of mitochondrial DNA (mtDNA)., Results: Our findings revealed that HOXC11 was overexpressed in CRC cells compared to normal colorectal cells and correlated with poorer prognosis in CRC patients. Knockout of HOXC11 reversed acquired chemoresistance in CRC cells. Furthermore, we observed a functional subset of HOXC11 localized to the mitochondria in chemoresistant CRC cells, which regulated mitochondrial function by modulating mtDNA transcription, thereby affecting chemoresistance., Conclusions: In summary, our study reveals that HOXC11 regulates mitochondrial function through the modulation of mtDNA transcription, impacting chemoresistance in colorectal cancer cells. These findings underscore the significance of understanding the molecular mechanisms underlying chemoresistance and highlight the potential therapeutic implications of targeting mitochondrial function in CRC treatment., (© 2024. The Author(s).)

Mitochondrial missense mutations and pathogenic variants have been implicated in the pathogenesis of COVID-19. This study evaluated the role of mitochondrial DNA (mtDNA) mutations and changes in gene expression in the progression of COVID-19 and their correlation with clinical characteristics. Next-generation sequencing with high throughput was used to identify mtDNA mutations in 30 COVID-19 patients compared to 20 healthy controls. The potential impact of identified mutations on protein structure and stability was predicted using bioinformatic tools. Quantitative real-time polymerase chain reaction was employed to assess the expression levels of mtDNA-encoded genes involved in oxidative phosphorylation in COVID-19 patients and healthy controls. Correlations between gene expression levels, clinical parameters, including leukocyte, lymphocyte, neutrophil, and platelet count, as well as creatinine, alanine transaminase (ALT), aspartate transaminase (AST), and blood urea nitrogen (BUN) levels, and disease severity were analyzed. We found 8 different mtDNA mutations in ND1, ND5, CO3, ATP6, and CYB genes, which were predicted to alter amino acids and decrease protein stability. Two missense unique mutations, C9555T in CO3 and A12418T in ND5 were identified and correlated with Complexes I and IV, respectively. This downregulation was correlated with age, elevated levels of leukocytes, lymphocytes, neutrophils, platelets, creatinine, ALT, AST, and BUN, as well as disease severity. These findings suggest that mtDNA mutations and altered expression of oxidative phosphorylation genes contribute to mitochondrial dysfunction in COVID-19. Targeting mitochondrial dysfunction may represent a promising therapeutic strategy for COVID-19 treatment.

The efficacy of vitamin C in age-related hearing loss, i.e., presbycusis, remains debatable. On a separate note, inflammation induced by the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome is involved in the progression of presbycusis. In this study, we investigated the effect of vitamin C on male C57BL/6 mice's presbycusis and NLRP3 inflammasome. The results showed that vitamin C treatment improved hearing, reduced the production of inflammatory factors, inhibited NLRP3 inflammasome activation, and decreased cytosolic mitochondrial DNA (mtDNA) in the C57BL/6 mouse cochlea, inferior colliculus, and auditory cortex. According to this study, vitamin C protects auditory function in male C57BL/6 presbycusis mice through reducing mtDNA release, inhibiting the NLRP3 inflammasome activation in the auditory pathway. Our study provides a theoretical basis for applying vitamin C to treat presbycusis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Low migratory dendritic cell (DC) levels pose a challenge in cancer immune surveillance, yet their impact on tumor immune status and immunotherapy responses remains unclear. We present clinical evidence linking reduced migratory DC levels to immune-cold tumor status, resulting in poor patient outcomes. To address this, we develop an autologous DC-based nanovaccination strategy using patient-derived organoid or cancer cell lysate-pulsed cationic nanoparticles (cNPs) to load immunogenic DC-derived microvesicles (cNP cancer cell @MV DC ). This approach transforms immune-cold tumors, increases migratory DCs, activates T cells and natural killer cells, reduces tumor growth, and enhances survival in orthotopic pancreatic and lung cancer models, surpassing conventional methods. In vivo imaging reveals superior cNP cancer cell @MV DC accumulation in tumors and lymph nodes, promoting immune cell infiltration. Mechanistically, cNPs enrich mitochondrial DNA, enhancing cGAS-STING-mediated DC activation and migration. Our strategy shifts cold tumors to a hot state, enhancing antitumor immunity for potential personalized cancer treatments., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Maternal inheritance of mitochondrial DNA (mtDNA) is a widespread phenomenon in eukaryotes. Our earlier research indicated that sperm mtDNA is removed prior to fertilization in mice, and Endonuclease G (ENDOG) orchestrates the degradation of sperm mitochondria in Caenorhabditis elegans. However, the mechanisms underlying sperm mtDNA disposal in mammals remain poorly understood. To investigate the potential role of ENDOG in sperm mtDNA elimination, we created Endog knockout (Endog-/-) mice. Our findings revealed that Endog-/- mice maintained normal spermatogenesis and fertility. Most strikingly, we detected no substantial discrepancy in sperm mtDNA copy number between Endog-/- and control mice. Furthermore, we noted that sperm mtDNA copy numbers were unchanged in both less motile and motile sperm isolated by Percoll gradient centrifugation from Endog-/- and control mice. Taken together, our results indicate that ENDOG is not essential for spermatogenesis or the elimination of sperm mtDNA in mice., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2024. Published by The Company of Biologists Ltd.)

The hoary fox (Lycalopex vetulus) is the only species of the Canidae (Mammalia: Carnivora) endemic to Brazil, and so far has been the target of few genetic studies. Using microsatellites and mtDNA markers, we investigated its present genetic diversity and population structure. We also tested the hypothesis that this species currently hybridizes with the pampas fox (L. gymnocercus), as suggested by previous mtDNA data from two individuals. We collected tissue and blood samples from animals representing most of the two species' distributions in Brazil (n = 87), including their recently discovered geographic contact zone in São Paulo state. We observed that the hoary fox exhibits high levels of genetic diversity and low levels of population structure. We identified six individuals from São Paulo state with clear evidence of hybridization based on introgressed pampas fox mitochondrial DNA and/or admixed microsatellite genotypes (three individuals bore both types of evidence). These results demonstrate the existence of admixed individuals between hoary and pampas foxes in southeastern Brazil, representing the first identified case of interspecies admixture between native South American canids. We discuss our findings in the context of the evolutionary history of these foxes and address potential conservation implications of this interspecies hybridization process., (© The Author(s) 2024. Published by Oxford University Press on behalf of The American Genetic Association. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Cisplatin remains the most widely used chemotherapeutic agent in cancer treatment; however, its inherent drawbacks have fueled the development of novel metalloanticancer drugs. In this study, two novel Cu(II) complexes (Cu1 and Cu2) were designed and synthesized. Notably, these Cu(II) complexes showed higher cytotoxicity against HL-7402 cells than cisplatin. Moreover, Cu(II) complexes significantly inhibited liver cancer growth in a xenograft model. A mechanism study revealed that the Cu(II) complexes reduced the mitochondrial membrane potential of cancer cells, produced excessive reactive oxygen species (ROS), induced mitochondrial DNA (mtDNA) damage, and ultimately facilitated cancer cell apoptosis., Competing Interests: Declaration of competing interest There are no conflicts to declare., (Copyright © 2023. Published by Elsevier Inc.)

Previous studies have shown mitochondrial dysfunction in schizophrenia (SZ) patients, which may be caused by mitochondrial DNA (mtDNA) alterations. However, there are few studies in SZ that have analyzed mtDNA in brain samples by next-generation sequencing (NGS). To address this gap, we used mtDNA-targeted NGS and qPCR to characterize mtDNA alterations in brain samples from patients with SZ (n = 40) and healthy controls (HC) (n = 40). 35 % of SZ patients showed mtDNA alterations, a significantly higher prevalence compared to 10 % of HC. Specifically, SZ patients had a significantly higher frequency of deletions (35 vs. 5 in HC), with a mean number of deletions of 3.8 in SZ vs. 1.0 in HC. Likely pathogenic missense variants were also significantly more frequent in patients with SZ than in HC (10 vs. three HC), encompassing 14 variants in patients and three in HC. The pathogenic tRNA variant m.3243A>G was identified in one SZ patient with a high heteroplasmy level of 32.2 %. While no significant differences in mtDNA copy number (mtDNA-CN) were observed between SZ and HC, antipsychotic users had significantly higher mtDNA-CN than non-users. These findings suggest a potential role for mtDNA alterations in the pathophysiology of SZ that require further validation and functional studies., Competing Interests: Declaration of competing interest The authors declare that they have no conflicts of interest., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: While the kinetics of human sperm nuclear DNA fragmentation (SDF-nDNA) following ejaculation have been described, the dynamics and relationships of mitochondrial DNA copy number per spermatozoon (mtDNAcn) and fragmentation (SDF-mtDNA) remain unexplored., Objectives: To compare post-ejaculatory kinetics of mtDNAcn, SDF-mtDNA and SDF-nDNA, global, single-strand DNA breaks (SDF-SSBs) and double-strand DNA breaks (SDF-DSBs) in normozoospermic and non-normozoospermic samples., Materials and Methods: 28 normozoospermic and 43 non-normozoospermic ejaculates were evaluated at 0, 6, 24 and 48 h of incubation in vitro. SDF-nDNA was determined by sperm chromatin dispersion (SCD) assays. mtDNAcn and SDF-mtDNA were analysed by dPCR., Results: SDF-nDNA-global values increased as a consequence of quadratic SDF-SSBs and linear SDF-DSBs kinetics. Non-normozoospermic samples showed a slower SDF-global rate between 6-24 h, due to lesser SSBs production. Regarding SDF-DSBs, non-normozoospermic samples exhibited a faster initial increase rate, followed by a slower final increment. The mtDNAcn median value decreased linearly, being 3.2× higher in non-normozoospermics at all time points; mtDNAcn in both cohorts reduced to half of the baseline by 48 h. mtDNAcn was identified as a risk factor for discriminating non-normozoospermia, a finding that was further strengthen when combined with SDF-Global or SDF-DSBs values. SDF-mtDNA frequencies were identical, increasing over time correspondingly in both cohorts. The mtDNA fragmentation rate was initially fast, decreasing progressively with time for both cohorts; half of the initially unfragmented copies were fragmented after 48 h. Rates of mtDNAcn loss and SDF-mtDNA increase were only marginally correlated with the rates of nuclear fragmentation., Conclusion: mtDNA fragmentation and loss occur post ejaculation. Their dynamics are likely to be associated with different and/or uncoupled mechanisms to that which cause nuclear DNA fragmentation. Our results indicate that while mtDNA fragmentation is not influenced by the sperm quality, the number of copies of sperm mtDNAcn can potentially serve as a risk factor for predicting non-normozoospermia., (© 2023 American Society of Andrology and European Academy of Andrology.)

Dibutyl phthalate (DBP) is a widely-used plasticizer that is dispersed in various environments, causing significant pollution and health risks. The toxic mechanism of DBP has been discussed in recent years, while the susceptibility of mitochondrial DNA (mtDNA) to DBP exposure and the resulting damage remain unclear. In this study, maternal zebrafish were exposed to environmentally relevant concentration of DBP for 0, 2, 4, and 6 weeks. Results showed that DBP exposure impaired health status, leading to the reduced body length and weight, condition factor, hepatosomatic index, and gonadosomatic index. Furthermore, DBP exposure induced oxidative stress and ATP deficiency in the gill and liver in a time-dependent manner. The oxidized mtDNA (ox-mtDNA) levels in the D-loop and ND1 regions were assessed in different tissues, showing distinct response patterns. The high energy-consuming tissues such as heart, brain, gill, and liver exhibited elevated susceptibility to mitochondrial damage, with a rapid increase in ox-mtDNA levels in the short term. Conversely, in muscle, ovary, eggs, and offspring, ox-mtDNA gradually accumulated over the exposure period. Notably, the ox-mtDNA levels in the D-loop region of blood showed a prompt response to DBP exposure, making it convenient for evaluation. Additionally, decreased hatching rates, increased mortality, lipoperoxidation, and depressed swimming performance were observed in offspring following maternal DBP exposure, suggesting the inherited impairments of maternal mtDNA. These findings highlight the potential for ox-mtDNA to serve as a convenient biomarker for environmental contamination, aiding in ecological risk assessment and forewarning systems in aquatic environment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Mitochondrial transcription factor A (TFAM) is a mitochondrial protein encoded by nuclear genes and transported from the cytoplasm to the mitochondria. TFAM is essential for the maintenance, expression, and delivery of mitochondrial DNA (mtDNA) and can regulate the replication and transcription of mtDNA. TFAM is associated with the formation of mtDNA nucleomimetic structures, mtDNA repair, and mtDNA stability. However, the mechanism by which TFAM protects mtDNA is still being studied. This review provides a summary of the protective mechanism of TFAM on mtDNA including the discrete regulatory effects of TFAM acetylation and phosphorylation on mtDNA, the regulation of Ca 2+ levels by TFAM to activate transcription in mitochondria, and the increased binding of TFAM to mtDNA damage hot spots. This review also discusses the association between TFAM and some neurodegenerative diseases., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Skeletal muscle aging and sarcopenia result in similar changes in the levels of aging markers. However, few studies have examined cancer sarcopenia from the perspective of aging. Therefore, this study investigated aging in cancer sarcopenia and explored its causes in vitro and in vivo. In mouse aging, in vitro cachexia, and mouse cachexia models, skeletal muscles showed similar changes in aging markers including oxidative stress, fibrosis, reduced muscle differentiation potential, and telomere shortening. Furthermore, examination of mitochondrial DNA from skeletal muscle revealed a 5 kb deletion in the major arc; truncation of complexes I, IV, and V in the electron transport chain; and reduced oxidative phosphorylation (OXPHOS). The mouse cachexia model demonstrated high levels of high-mobility group box-1 (HMGB1) and tumor necrosis factor-α (TNFα) in cancer ascites. Continuous administration of neutralizing antibodies against HMGB1 and TNFα in this model reduced oxidative stress and abrogated mitochondrial DNA deletion. These results suggest that in cancer sarcopenia, mitochondrial oxidative stress caused by inflammatory cytokines leads to mitochondrial DNA damage, which in turn leads to decreased OXPHOS and the promotion of aging., Competing Interests: The authors declare no conflict of interest.

Alterations in mitochondrial function have been linked to a variety of cellular and organismal stress responses including apoptosis, aging, neurodegeneration and tumorigenesis. However, adaptation to mitochondrial dysfunction can occur through the activation of survival pathways, whose mechanisms are still poorly understood. The yeast Saccharomyces cerevisiae is an invaluable model organism for studying how mitochondrial dysfunction can affect stress response and adaptation processes. In this study, we analyzed and compared in the absence and in the presence of osmostress wild-type cells with two models of cells lacking mitochondrial DNA: ethidium bromide-treated cells (ρ 0 ) and cells lacking the mitochondrial pyrimidine nucleotide transporter RIM2 (Δ RIM2 ). Our results revealed that the lack of mitochondrial DNA provides an advantage in the kinetics of stress response. Additionally, wild-type cells exhibited higher osmosensitivity in the presence of respiratory metabolism. Mitochondrial mutants showed increased glycerol levels, required in the short-term response of yeast osmoadaptation, and prolonged oxidative stress. The involvement of the mitochondrial retrograde signaling in osmoadaptation has been previously demonstrated. The expression of CIT2 , encoding the peroxisomal isoform of citrate synthase and whose up-regulation is prototypical of RTG pathway activation, appeared to be increased in the mutants. Interestingly, selected TCA cycle genes, CIT1 and ACO1 , whose expression depends on RTG signaling upon stress, showed a different regulation in ρ 0 and Δ RIM2 cells. These data suggest that osmoadaptation can occur through different mechanisms in the presence of mitochondrial defects and will allow us to gain insight into the relationships among metabolism, mitochondria-mediated stress response, and cell adaptation., Competing Interests: The authors declare no conflicts of interest.

Glaucoma is a leading cause of irreversible blindness worldwide which affects all age groups. It is often identified by high intraocular pressure, characteristic optic neuropathy, and vision loss. Due to multifactorial nature of glaucoma pathogenesis, the molecular events responsible for its precipitation are currently poorly understood. Mitochondrial DNA (mtDNA) variations which are inherited maternally are being closely studied in recent times to elucidate the effect on glaucoma. Mitochondrial genetic studies till date have found a possible link between Leber hereditary optic neuropathy loci and glaucoma but with conflicting views. Furthermore, whole mtDNA studies in glaucoma points at the involvement of oxidative phosphorylation complex I and specifically the NADH dehydrogenase 5 gene in glaucoma. This review focuses on identifying the potential genes and variations in the maternally inherited mtDNA which might be involved in glaucoma pathogenesis., Competing Interests: There are no conflicts of interest., (Copyright: © 2024 Middle East African Journal of Ophthalmology.)

Molluscan mitochondrial genomes are unusual because they show wide variation in size, radical genome rearrangements and frequently show high variation (> 10%) within species. As progress in understanding this variation has been limited, we used whole genome sequencing of a six-generation matriline of the terrestrial snail Cepaea nemoralis, as well as whole genome sequences from wild-collected C. nemoralis, the sister species C. hortensis, and multiple other snail species to explore the origins of mitochondrial DNA (mtDNA) variation. The main finding is that a high rate of SNP heteroplasmy in somatic tissue was negatively correlated with mtDNA copy number in both Cepaea species. In individuals with under ten mtDNA copies per nuclear genome, more than 10% of all positions were heteroplasmic, with evidence for transmission of this heteroplasmy through the germline. Further analyses showed evidence for purifying selection acting on non-synonymous mutations, even at low frequency of the rare allele, especially in cytochrome oxidase subunit 1 and cytochrome b. The mtDNA of some individuals of Cepaea nemoralis contained a length heteroplasmy, including up to 12 direct repeat copies of tRNA-Val, with 24 copies in another snail, Candidula rugosiuscula, and repeats of tRNA-Thr in C. hortensis. These repeats likely arise due to error prone replication but are not correlated with mitochondrial copy number in C. nemoralis. Overall, the findings provide key insights into mechanisms of replication, mutation and evolution in molluscan mtDNA, and so will inform wider studies on the biology and evolution of mtDNA across animal phyla., (© 2024. The Author(s).)

Among the six mitochondrial DNA lineages of the black rat ( Rattus rattus Complex; RrC), lineages II and IV are widespread in Southeast and East Asia. This study explored their demographic history using 17 new sequences from the Miyako Islands in the Ryukyu archipelago, together with 178 publicly available cytochrome b sequences. We defined six and two haplotype groups showing rapid population expansion signals in Lineages II and IV, respectively. The six haplotype groups of Lineage II were represented by haplotypes from 1) Myanmar/Bangladesh/Northeast India, 2) Laos, 3) Thailand, 4) Indonesia/Philippines, 5) Vietnam/southern China, and 6) the Ryukyu archipelago. These expansion times were estimated using time-dependent evolutionary rates to be 115,300 years ago (ya), 128,500 ya, 9600 ya, 10,600 ya, 7200 ya, and 1400 ya, respectively, although all had large confidence intervals. The two groups of Lineage IV were recovered from the mainland and islands of Southeast Asia with predicted expansion times of 197,000 ya and 5800 ya, respectively. These results suggest that climatic fluctuations during the last 200,000 years of the Quaternary, affected the population dynamics in subtropical areas at different times. Furthermore, the results of the younger rapid expansion events of RrC suggest the possibility of agricultural advancement and dispersal of Neolithic farmers to different areas within the mainland and islands of Southeast Asia during the Holocene. A subset of rats from the Miyako Islands were found to have the same lineage IV haplotypes as those in Southeast Asia, suggesting a recent introduction of these new lineages.

Circulating cell-free mitochondrial DNA (ccf-mtDNA) is an indicator of cell death, inflammation, and oxidative stress. ccf-mtDNA in pregnancies with placental dysfunction differs from that in healthy pregnancies, and the direction of this difference depends on gestational age and method of mtDNA quantification. Reactive oxygen species (ROS) trigger release of mtDNA, yet it is unknown whether trophoblast cells release mtDNA in response to oxidative stress, a common feature of pregnancies with placental pathology. We hypothesized that oxidative stress would induce cell death and release of mtDNA from trophoblast cells. BeWo cells were treated with antimycin A (10-320 µM) or rotenone (0.2-50 µM) to induce oxidative stress. A multiplex real-time quantitative PCR (qPCR) assay was used to quantify mtDNA and nuclear DNA in membrane-bound, non-membrane-bound, and vesicle-bound forms in cell culture supernatants and cell lysates. Treatment with antimycin A increased ROS ( P < 0.0001), induced cell necrosis ( P = 0.0004) but not apoptosis ( P = 0.6471), and was positively associated with release of membrane-bound and non-membrane-bound mtDNA ( P < 0.0001). Antimycin A increased mtDNA content in exosome-like extracellular vesicles (vesicle-bound form; P = 0.0019) and reduced autophagy marker expression (LC3A/B, P = 0.0002; p62, P < 0.001). Rotenone treatment did not influence mtDNA release or cell death ( P > 0.05). Oxidative stress induces release of mtDNA into the extracellular space and causes nonapoptotic cell death and a reduction in autophagy markers in BeWo cells, an established in vitro model of human trophoblast cells. Intersection between autophagy and necrosis may mediate the release of mtDNA from the placenta in pregnancies exposed to oxidative stress. NEW & NOTEWORTHY This is the first study to test whether trophoblast cells release mitochondrial (mt)DNA in response to oxidative stress and to identify mechanisms of release and biological forms of mtDNA from this cellular type. This research identifies potential cellular mechanisms that can be used in future investigations to establish the source and biomarker potential of circulating mtDNA in preclinical experimental models and humans.

Cardiovascular disease (CVD) is a leading global cause of mortality, difficult to predict in advance. Evidence indicates that the copy number of mitochondrial DNA (mtDNAcn) in blood is altered in individuals with CVD. MtDNA released into circulation may act as a mediator of inflammation, a recognized factor in the development of CVD, in the long distance. This pilot study aims to test if levels of mtDNAcn in buffy coat DNA (BC-mtDNA), in circulating cellfree DNA (cf-mtDNA), or in DNA extracted from plasma extracellular vesicles (EV-mtDNA) are altered in CVD patients and if they can predict heart attack in advance. A group of 144 people with different CVD statuses (50 that had CVD, 94 healthy) was selected from the LifeLines Biobank according to the incidence of new cardiovascular event monitored in 6 years (50 among controls had heart attack after the basal assessment). MtDNAcn was quantified in total cf-DNA and EV-DNA from plasma as well as in buffy coat. EVs have been characterized by their size, polydispersity index, count rate, and zeta potential, by Dynamic Light Scattering. BC-mtDNAcn and cf-mtDNAcn were not different between CVD patients and healthy subjects. EVs carried higher mtDNAcn in subject with a previous history of CVD than controls, also adjusting the analysis for the EVs derived count rate. Despite mtDNAcn was not able to predict CVD in advance, the detection of increased EV-mtDNAcn in CVD patients in this pilot study suggests the need for further investigations to determine its pathophysiological role in inflammation., (© 2024 The Author(s). The FASEB Journal published by Wiley Periodicals LLC on behalf of Federation of American Societies for Experimental Biology.)

Background: In today's world, appearance is an important factor in almost all areas of our lives. Therefore, it has become common to use dyes to color foods to make them look appetizing and visually appealing. However, food additives have negative effects on biochemical processes in cells at both high and low doses., Methods and Results: This study investigated the effect of carmoisine, a commonly used food coloring, on oxidative stress and damage parameters in Drosophila melanogaster in terms of both enzymatic and gene expression. The change in mitochondrial DNA copy number (mtDNA-CN), a marker of oxidative stress, was also examined. When the data obtained were analyzed, it was observed that carmoisine caused a significant decrease in GSH levels depending on the increase in dose. SOD, CAT, GPx, and AChE enzyme activities and gene expression levels were also found to be significantly decreased. All groups also showed a significant decrease in mtDNA-CN. The effect of carmoisine on Drosophila melanogaster morphology was also investigated in our study. However, no significant change was observed in terms of morphological development in any group., Conclusions: When all the findings were evaluated together, it was observed that carmoisin triggered oxidative stress and these effects became more risky at high doses. Therefore, we believe that the consumer should be made more aware of the side effects of azo dyes in food and that the type and concentration of each substance added to food should be specified., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Mitochondria are subcellular organelles essential for life. Beyond their role in producing energy, mitochondria govern various physiological mechanisms, encompassing energy generation, metabolic processes, apoptotic events, and immune responses. Mitochondria also contain genetic material that is susceptible to various forms of damage. Mitochondrial double-stranded breaks (DSB) are toxic lesions that the nucleus repairs promptly. Nevertheless, the significance of DSB repair in mammalian mitochondria is controversial. This review presents an updated view of the available research on the consequences of mitochondrial DNA DSB from the molecular to the cellular level. We discuss the crucial function of mitochondrial DNA damage in regulating processes such as senescence, integrated stress response, and innate immunity. Lastly, we discuss the potential role of mitochondrial DNA DSB in mediating the cellular consequences of ionizing radiations, the standard of care in treating solid tumors., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Mitochondria are pleiotropic organelles central to an array of cellular pathways including metabolism, signal transduction, and programmed cell death. Mitochondria are also key drivers of mammalian immune responses, functioning as scaffolds for innate immune signaling, governing metabolic switches required for immune cell activation, and releasing agonists that promote inflammation. Mitochondrial DNA (mtDNA) is a potent immunostimulatory agonist, triggering pro-inflammatory and type I interferon responses in a host of mammalian cell types. Here we review recent advances in how mtDNA is detected by nucleic acid sensors of the innate immune system upon release into the cytoplasm and extracellular space. We also discuss how the interplay between mtDNA release and sensing impacts cellular innate immune endpoints relevant to health and disease., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Mitochondrial DNA (mtDNA) exhibits distinct characteristics distinguishing it from the nuclear genome, necessitating specific analytical methods in genetic studies. This comprehensive review explores the complex role of mtDNA in a variety of genetic studies, including genome-wide, epigenome-wide, and phenome-wide association studies, with a focus on its implications for human traits and diseases. Here, we discuss the structure and gene-encoding properties of mtDNA, along with the influence of environmental factors and epigenetic modifications on its function and variability. Particularly significant are the challenges posed by mtDNA's high mutation rate, heteroplasmy, and copy number variations, and their impact on disease susceptibility and population genetic analyses. The review also highlights recent advances in methodological approaches that enhance our understanding of mtDNA associations, advocating for refined genetic research techniques that accommodate its complexities. By providing a comprehensive overview of the intricacies of mtDNA, this paper underscores the need for an integrated approach to genetic studies that considers the unique properties of mitochondrial genetics. Our findings aim to inform future research and encourage the development of innovative methodologies to better interpret the broad implications of mtDNA in human health and disease.

Objectives: As antibiotics become more prevalent, accuracy and safety are critical. Moxifloxacin (MXF) have been reported to have immunomodulatory effects on a variety of immune cells and even anti-proliferative and pro-apoptotic effects, but the mechanism of action is not fully clear., Methods: Peripheral blood mononuclear cells (PBMC) from experimental groups of healthy adults (n = 3) were treated with MXF (10ug/ml) in vitro for 24 h. Single-cell sequencing was performed to investigate differences in the response of each immune cell to MXF. Flow cytometry determined differential gene expression in subsets of most damaged NK cells. Pseudo-time analysis identified drivers that influence MXF-stimulated cell differentiation. Detection of mitochondrial DNA and its involvement in the mitochondrial respiratory chain pathway clarifies the origin of MXF-induced stress injury., Results: Moxifloxacin-environmental NK cells are markedly reduced: a new subset of NK cells emerges, and immediate-early-response genes in this subset indicate the presence of an early activation response. The inhibitory receptor-dominant subset shows enhanced activation, leading to increased expression of cytokines and chemokines. The near-mature subset showed greater cytotoxicity and the most pronounced cellular damage. CD56bright cells responded by antagonizing the regulation of activation and inhibitory signals, demonstrating a strong cleavage capacity. The severe depletion of mitochondrial genes was focused on apoptosis induced by the mitochondrial respiratory chain complex., Conclusion: NK cells exhibit heightened sensitivity to the MXF environment. Different NK subsets upregulate the expression of cytokines and chemokines through different activation pathways. Concurrently, MXF induces impairment of the mitochondrial oxidative phosphorylation system, culminating in apoptosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: Extracellular mitochondrial DNA (mtDNA) is released from damaged cells and increases in the serum and bronchoalveolar lavage fluid (BALF) of idiopathic pulmonary fibrosis (IPF) patients. While increased levels of serum mtDNA have been reported to be linked to disease progression and the future development of acute exacerbation (AE) of IPF (AE-IPF), the clinical significance of mtDNA in BALF (BALF-mtDNA) remains unclear. We investigated the relationships between BALF-mtDNA levels and other clinical variables and prognosis in IPF., Methods: Extracellular mtDNA levels in BALF samples collected from IPF patients were determined using droplet-digital PCR. Levels of extracellular nucleolar DNA in BALF (BALF-nucDNA) were also determined as a marker for simple cell collapse. Patient characteristics and survival information were retrospectively reviewed., Results: mtDNA levels in serum and BALF did not correlate with each other. In 27 patients with paired BALF samples obtained in a stable state and at the time of AE diagnosis, BALF-mtDNA levels were significantly increased at the time of AE. Elevated BALF-mtDNA levels were associated with inflammation or disordered pulmonary function in a stable state (n = 90), while being associated with age and BALF-neutrophils at the time of AE (n = 38). BALF-mtDNA ≥ 4234.3 copies/µL in a stable state (median survival time (MST): 42.4 vs. 79.6 months, p < 0.001) and ≥ 11,194.3 copies/µL at the time of AE (MST: 2.6 vs. 20.0 months, p = 0.03) were associated with shorter survival after BALF collection, even after adjusting for other known prognostic factors. On the other hand, BALF-nucDNA showed different trends in correlation with other clinical variables and did not show any significant association with survival time., Conclusions: Elevated BALF-mtDNA was associated with a poor prognosis in both IPF and AE-IPF. Of note, at the time of AE, it sharply distinguished survivors from non-survivors. Given the trends shown by analyses for BALF-nucDNA, the elevation of BALF-mtDNA might not simply reflect the impact of cell collapse. Further studies are required to explore the underlying mechanisms and clinical applications of BALF-mtDNA in IPF., (© 2024. The Author(s).)

Excessive fluoride can adversely affect bone mineral density (BMD). Oxidative stress and mitochondrial dysfunction are crucial mechanisms of health damage induced by fluoride. Here, a cross-sectional survey involving 907 Chinese farmers (aged 18-60) was carried out in Tongxu County in 2017, aiming to investigate the significance of mitochondrial DNA copy number (mtDNAcn) and oxidative stress in fluoride-related BMD change. Concentrations of urinary fluoride (UF), serum oxidative stress biomarkers, including total antioxidant capacity (T-AOC), total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA), as well as relative mtDNAcn in peripheral blood were determined. The multivariable linear model and mediation analysis were performed to assess associations between UF, oxidative stress, and relative mtDNAcn with BMD. Results showed that GSH-Px levels increased by 6.98 U/mL [95% confidence interval (CI) 3.41-10.56)] with each 1.0 mg/L increment of UF. After stratification, the T-AOC, relative mtDNAcn, and BMD decreased by 0.04 mmol/L (-0.08 ~ -0.01), 0.29-unit (-0.55 ~ -0.04), and 0.18-unit (-0.33 ~ -0.03) with every 1.0 mg/L elevation of UF in the excessive fluoride group (EFG, adults with UF > 1.6 mg/L), respectively. Furthermore, T-AOC and relative mtDNAcn were favorably related to the BMD in the EFG (β = 0.82, 95%CI 0.16-1.48 for T-AOC; β = 0.11, 95%CI 0.02-0.19 for relative mtDNAcn). Mediation analysis showed that relative mtDNAcn and T-AOC mediated 15.4% and 17.1% of the connection between excessive fluoride and reduced BMD, respectively. Findings suggested that excessive fluoride was related to lower BMD in adults, and the decrement of T-AOC and relative mtDNAcn partially mediate this relationship., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Background and Objectives: Platelet storage lesion (PSL) adversely affects the quality of platelet concentrates (PCs). Platelets are prone to activation during storage. Moreover, elevated free mitochondrial DNA (mtDNA) levels in PCs are associated with a higher risk of adverse transfusion reactions. Therefore, we aimed to evaluate the correlation between platelet activation markers and mtDNA release during PC storage., Materials and Methods: Six PCs prepared by the platelet-rich plasma method were assessed for free mtDNA copy number using quantitative real-time PCR and CD62P (P-selectin) expression by flow cytometry on days 0 (PC collection day), 3, 5 and 7 of storage. Lactate dehydrogenase (LDH) activity, pH, platelet count, mean platelet volume (MPV) and platelet distribution width (PDW) were measured as well. The correlation between free mtDNA and other PSL parameters, and the correlation between all parameters, was determined., Results: Significant increases in free mtDNA, MPV and PDW, and a significant decrease in platelet count and pH were observed. CD62P expression and LDH activity elevated significantly, particularly on storage days 5-7 and 0-3, respectively. Moreover, a moderate positive correlation (r = 0.61) was observed between free mtDNA and CD62P expression. The r values between free mtDNA and LDH, pH, platelet count, MPV and PDW were 0.81, -0.72, -0.49, 0.81 and 0.77, respectively., Conclusion: The interplay between platelet activation and mtDNA release in promoting PSL in PCs may serve as a promising target for future research on applying additive solutions and evaluating the quality of PCs to improve transfusion and clinical outcomes., (© 2024 International Society of Blood Transfusion.)

Background: Patients with sarcoidosis who develop severe clinical phenotypes of pulmonary fibrosis or multiorgan disease experience debilitating symptoms, with fatigue being a common chief complaint. Studies that have investigated this patient-related outcome measure (PROM) have used the Fatigue Assessment Scale (FAS), a self-reported questionnaire that reflects mental and physical domains. Despite extensive work, its cause is unknown and treatment options remain limited. Previously, we showed that the plasma of patients with sarcoidosis with extrapulmonary disease endorsing fatigue was enriched for mitochondrial DNA (mtDNA), a ligand for the innate immune receptor toll-like receptor 9 (TLR9). Through our cross-disciplinary platform, we investigated a relationship between sarcoidosis-induced fatigue and circulating mtDNA., Research Question: Is there a psychobiologic mechanism that connects sarcoidosis-induced fatigue and mtDNA-mediated TLR9 activation?, Study Design and Methods: Using a local cohort of patients at Yale (discovery cohort) and the National Institutes of Health-sponsored Genomic Research in Alpha-1 Antitrypsin Deficiency and Sarcoidosis study (validation cohort), we scored the FAS and quantified in the plasma, mtDNA concentrations, TLR9 activation, and cytokine levels., Results: Although FAS scores were independent of corticosteroid use and Scadding stage, we observed a robust association between FAS scores, which included mental and physical domains, and multiorgan sarcoidosis. Subsequently, we identified a significant correlation between plasma mtDNA concentrations and all domains of fatigue. Additionally, we found that TLR9 activation is associated with all aspects of the FAS and partially mediates this PROM through mtDNA. Last, we found that TLR9-associated soluble mediators in the plasma are independent of all facets of fatigue., Interpretation: Through our cross-disciplinary translational platform, we identified a previously unrecognized psychobiologic connection between sarcoidosis-induced fatigue and circulating mtDNA concentrations. Mechanistic work that investigates the contribution of mtDNA-mediated innate immune activation in this PROM and clinical studies with prospective cohorts has the potential to catalyze novel therapeutic strategies for this patient population and those with similar conditions., Competing Interests: Financial/Nonfinancial Disclosures None declared., (Copyright © 2023 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)

Eosinophils play a crucial role in host defense while also contributing to immunopathology through the release of inflammatory mediators. Characterized by distinctive cytoplasmic granules, eosinophils securely store and rapidly release various proteins exhibiting high toxicity upon extracellular release. Among these, major basic protein 1 (MBP-1) emerges as an important mediator in eosinophil function against pathogens and in eosinophil-associated diseases. While MBP-1 targets both microorganisms and host cells, its precise mechanism remains elusive. We demonstrate that formation of small pores by MBP-1 in lipid bilayers induces membrane permeabilization and disrupts potassium balance. Additionally, we reveal that mitochondrial DNA (mtDNA) present in eosinophil extracellular traps (EETs) amplifies MBP-1 toxic effects, underscoring the pivotal role of mtDNA in EETs. Furthermore, we present evidence indicating that absence of CpG methylation in mtDNA contributes to the regulation of MBP-1-mediated toxicity. Taken together, our data suggest that the mtDNA scaffold within extracellular traps promotes MBP-1 toxicity., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Cerebrovascular disease accounts for major neurologic disabilities in patients with type 2 diabetes mellitus (DM). A potential association of mitochondrial DNA ( mtDNA ) and inflammation with cerebral vessel remodeling in patients with type 2 DM was evaluated. A cohort of 150 patients and 30 healthy controls were assessed concerning urinary albumin/creatinine ratio (UACR), synaptopodin, podocalyxin, kidney injury molecule-1 (KIM-1), N-acetyl-β-(D)-glucosaminidase (NAG), interleukins IL-17A, IL-18, IL-10, tumor necrosis factor-alpha (TNFα), intercellular adhesion molecule-1 (ICAM-1). MtDNA-CN and nuclear DNA ( nDNA ) were quantified in peripheral blood and urine by qRT-PCR. Cytochrome b ( CYTB ) gene, subunit 2 of NADH dehydrogenase ( ND2 ), and beta 2 microglobulin nuclear gene ( B2M ) were assessed by TaqMan assays. mtDNA-CN was defined as the ratio of the number of mtDNA/nDNA copies, through analysis of the CYTB/B2M and ND2/B2M ratio; cerebral Doppler ultrasound: intima-media thickness (IMT)-the common carotid arteries (CCAs), the pulsatility index (PI) and resistivity index (RI)- the internal carotid arteries (ICAs) and middle cerebral arteries (MCAs), the breath-holding index (BHI). The results showed direct correlations of CCAs-IMT, PI-ICAs, PI-MCAs, RI-ICAs, RI-MCAs with urinary mtDNA , IL-17A, IL-18, TNFα, ICAM-1, UACR, synaptopodin, podocalyxin, KIM-1, NAG, and indirect correlations with serum mtDNA , IL-10. BHI correlated directly with serum IL-10, and serum mtDNA , and negatively with serum IL-17A, serum ICAM-1, and NAG. In neurologically asymptomatic patients with type 2 DM cerebrovascular remodeling and impaired cerebrovascular reactivity may be associated with mtDNA variations and inflammation from the early stages of diabetic kidney disease.