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Block copolymers consisting of poly(ethylene glycol) (PEG) and poly(amino acid)-based random copolymers were successfully synthesized by the ring opening polymerization of the N-carboxy anhydrides (NCA) of l-lysine and l-phenylalanine. The synthesized copolymers had a molecular weight of around 30,000 and contained l-lysine and l-phenylalanine residues with molar ratios of 10/0, 9/1, 8/2, 7/3 and 6/4. The complex formation of the copolymer and pCMV-luc plasmid DNA was confirmed by the gel retardation assay and zeta potential measurement. Complete neutralization was achieved at an N/P ratio of more than 1.0 and the size of the complex was determined to be around 150 nm by dynamic light scattering. The cytotoxicity and transfection efficiency were tested on the HEK 293T cell line. The synthesized copolymers displayed negligible cytotoxicity, resulting in a cell viability of more than 95%, while those of the poly(l-lysine) (PLL) and poly(ethylenimine) (PEI) homopolymer were around 65 and 55%, respectively, under comparable conditions. The introduction of the hydrophilic PEG is believed to reduce the toxicity of the copolymer, due to its enhanced biocompatibility, and to impart improved stability to the complex under physiological conditions. The transfection efficiency at the optimized charge ratio of 7 was dramatically improved as the molar content of the l-phenylalanine residues in the copolymers increased and reached a maximum value at an l-phenylalanine content of 30 mol%. The transfection efficiency of the PEGK7/plasmid DNA complex was around 80 times higher than that of PLL, despite the presence of neutral PEG as a block segment. [ABSTRACT FROM AUTHOR]

Echinochrome A (EchA) is a marine bioproduct extracted from sea urchins having antioxidant, antimicrobial, anti-inflammatory, and chelating effects, and is the active component of the clinical drug histochrome. We investigated the potential use of Ech A for inducing cardiomyocyte differentiation from mouse embryonic stem cells (mESCs). We also assessed the effects of Ech A on mitochondrial mass, inner membrane potential (Δψm), reactive oxygen species generation, and levels of Ca2+. To identify the direct target of Ech A, we performed in vitro kinase activity and surface plasmon resonance binding assays. Ech A dose-dependently enhanced cardiomyocyte differentiation with higher beating rates. Ech A (50 μM) increased the mitochondrial mass and membrane potential but did not alter the mitochondrial superoxide and Ca2+ levels. The in vitro kinase activity of the atypical protein kinase C-iota (PKCι) was significantly decreased by 50 μM of Ech A with an IC50 for PKCι activity of 107 μM. Computational protein-ligand docking simulation results suggested the direct binding of Ech A to PKCι, and surface plasmon resonance confirmed the direct binding with a low KD of 6.3 nM. Therefore, Ech A is a potential drug for enhancing cardiomyocyte differentiation from mESCs through direct binding to PKCι and inhibition of its activity. [ABSTRACT FROM AUTHOR]

An abstract of the article "An Efficient GLP-1 Expression System Using Two Step Transcription Amplification for Type 2 Diabetes Gene Therapy," by Kyung Soo Ko and colleagues is presented.

Abstract Unlike stable and immobile cell line conditions, animal hearts contract and relax to pump blood throughout the body. Mitochondria play an essential role by producing biological energy molecules to maintain heart function. In this study, we assessed the effect of heart mimetic cyclic stretch on mitochondria in a cardiac cell line. To mimic the geometric and biomechanical conditions surrounding cells in vivo, cyclic stretching was performed on HL-1 murine cardiomyocytes seeded onto an elastic micropatterned substrate (10% elongation, 0.5 Hz, 4 h/day). Cell viability, semi-quantitative Q-PCR, and western blot analyses were performed in non-stimulated control and cyclic stretch stimulated HL-1 cell lines. Cyclic stretch significantly increased the expression of mitochondria biogenesis-related genes (TUFM, TFAM, ERRα, and PGC1-α) and mitochondria oxidative phosphorylation-related genes (PHB1 and CYTB). Western blot analysis confirmed that cyclic stretch increased protein levels of mitochondria biogenesis-related proteins (TFAM, and ERRα) and oxidative phosphorylation-related proteins (NDUFS1, UQCRC, and PHB1). Consequently, cyclic stretch increased mitochondrial mass and ATP production in treated cells. Our results suggest that cyclic stretch transcriptionally enhanced mitochondria biogenesis and oxidative phosphorylation without detrimental effects in a cultured cardiac cell line. [ABSTRACT FROM AUTHOR]

Cereblon (CRBN) has been reported as a negative regulator of adenosine monophosphate-activated protein kinase (AMPK). Aerobic exercise training has been shown to increase AMPK, which resulted in glucose regulation in skeletal muscle. However, the expression level of CRBN and its association with the physiological modulation of glucose are still unclear. Male Sprague-Dawley rats (5-week-old, n = 18) were assigned to control, streptozotocin (STZ, 65 mg/kg)-induced diabetic group, and STZ + exercise (STZ + EXE) group with six rats in each group. Rats in the STZ + EXE group exercised by treadmill running (20 m/min, 60 min, 4 times/week) for 8 weeks. Compared with the STZ group, blood glucose was significantly decreased in the STZ + EXE group. The skeletal muscle of rats in the STZ + EXE group showed a significant decrease in CRBN levels and an increase in AMPK, protein kinase B, peroxisome proliferator-activated receptor gamma coactivator 1-alpha, fibronectin type III domain-containing protein 5, glucose transporter type 4, superoxide dismutase 1, and uncoupling protein 3 levels. These results suggest that CRBN is a potential regulator of glucose homeostasis in the skeletal muscle. Moreover, our results suggest that aerobic exercise training may provide an important physiological treatment for type 1 diabetes by decreasing CRBN and increasing AMPK signaling in skeletal muscle. [ABSTRACT FROM AUTHOR]

An abstract of the article "DNA Delivery to the Mitochondria Sites Using Leader Peptide Conjugated Polyethylenimine," by Minhyung Lee, Joon Sig Choi and Kyung Soo Ko is presented.

Aims/Introduction Sleep disturbances caused by painful diabetic neuropathy ( PDN) might have substantial impacts on the multifaceted aspects of PDN, including quality of life. There are no convincing data on the validation or reliability of sleep problem measurements in patients with PDN in Korea. This large population-based cross-sectional study examined psychometric properties of the Medical Outcomes Study ( MOS) Sleep Scale in patients with PDN in Korea. Materials and Methods Measurements of patient-reported outcomes ( Brief Pain Inventory-short form, MOS Sleep Scale and Euro Qo L Health [ EQ-5D]) were documented. PDN was diagnosed if the average daily pain intensity was ≥4 based on the visual analog scale or if patients were taking medication for their current pain. Results There were 577 patients with PDN (41.6% with diabetic peripheral neuropathy). The internal consistency of reliability for the MOS Sleep Scale was 0.80 as measured by Cronbach's alpha. The extent to which multiple items in a dimension were intercorrelated and formed a dimension measuring the same underlying concept ( Pearson's correlation coefficient) ranged from 0.24 to 0.71 (all P < 0.001). Each item of the MOS Sleep Scale was significantly correlated with the average pain score and the pain interference score ( Pearson's correlation coefficients ranged from 0.20 to 0.28 and from 0.29 to 0.40, respectively; all P < 0.001). The correlations between the EQ-5 D index and the MOS Sleep Scale ranged from −0.27 to −0.31 (all P < 0.001). Conclusions The MOS Sleep Scale showed good reliability in the evaluation of PDN in Korean type 2 diabetic patients. [ABSTRACT FROM AUTHOR]

Aims Preservation of mitochondrial function is essential to limit myocardial damage in ischaemic heart disease. We examined the protective effects and mechanism of a new compound, NecroX-5, on rat heart mitochondria in a hypoxia/reoxygenation (HR) model. Methods and results NecroX-5 reduced mitochondrial oxidative stress, prevented the collapse in mitochondrial membrane potential, improved mitochondrial oxygen consumption, and suppressed mitochondrial Ca2+ overload during reoxygenation in an in vitro rat heart HR model. Furthermore, NecroX-5 reduced the ouabain- or histamine-induced increase in mitochondrial Ca2+. Conclusion These findings suggest that NecroX-5 may act as a mitochondrial Ca2+ uniporter inhibitor to protect cardiac mitochondria against HR damage. [ABSTRACT FROM PUBLISHER]

Abstract: A membrane receptor, Fas (CD95), and its ligand FasL have been considered as key players in diabetes pathogenesis. They are known to mediate interactions between β cells and cytotoxic T cells, which results in apoptotic cell death. We hypothesized that the interruption of Fas–FasL interactions by suppressing Fas expression in β cells would affect the development of diabetes. The effect of Fas-silencing siRNA (Fas siRNA) on diabetes development was evaluated in a cyclophosphamide (CY)-accelerated diabetes animal model after intravenous administration using a polymeric carrier, polyethylenimine (PEI). The systemic non-viral delivery of Fas siRNA showed significant delay in diabetes incidence up to 40days, while the control mice treated with naked Fas siRNA, scrambled dsRNA, or PBS were afflicted with diabetes within 20days. The retardation of diabetes incidence after the treatment of Fas siRNA may be due to the delayed progression of the pancreatic insulitis. In this study, the potential use of a non-viral carrier based siRNA gene therapy for the prevention of type-1 diabetes is demonstrated. [Copyright &y& Elsevier]

Abstract: In this research, a recombinant high mobility group box 1 AB peptide with a 6-histidine tag (rHMGB1AB-His6) was produced and characterized as a carrier of nucleic acids. The human HMGB1AB cDNA was cloned by RT-PCR. The rHMGB1AB-His6 expression vector, pET21a-rHMGB1AB-His6, was constructed with the cDNA. In pET21a-rHMGB1AB-His6, the acidic box of the C-terminus of wild type HMGB1 was eliminated, since it had negative charges and interfered with the DNA and peptide interaction. pET21a-rHMGB1AB-His6 was transformed into the BL21 strain. rHMGB1AB-His6 was produced by IPTG induction and purified using a nickel column. A gel retardation assay showed that plasmid DNA (pDNA) was completely retarded at a 1:1 weight ratio. The complex size was approximately 150nm at a 1:10 weight ratio (pDNA/rHMGB1AB-His6) and had a tendency to increase with increasing amount of rHMGB1AB-His6. The cytotoxicity of rHMGB1AB-His6 was compared with poly-l-lysine (PLL, 20kDa). As a result, rHMGB1AB-His6 did not show any cytotoxicity to 293 cells, while PLL had a greater cytotoxicity. rHMGB1AB-His6 had the highest transfection efficiency at a 1:40 weight ratio (pDNA/rHMGB1AB-His6). In addition, rHMGB1AB-His6 showed comparable transfection efficiency to PLL. With low cytotoxicity and moderate transfection efficiency, rHMGB1AB-His6 may be useful for delivery of nucleic acids. [Copyright &y& Elsevier]

Abstract: Glucagon-like peptide 1 (GLP-1) is an insulinotropic protein. It was reported that the continuous infusion of GLP-1 normalized the blood glucose level in type 2 diabetes animal model. However, the short half-life of GLP-1 has limited its application in clinical settings and prompted us to develop a GLP-1 gene therapy system. Our previous results showed that the delivery of pβ-GLP-1 using polyethylenimine (PEI) reduced the blood glucose level effectively. However, the glucose level was not completely normalized. In the present study, the more efficient GLP-1 expression system was developed using two-step transcription amplification (TSTA). To evaluate the TSTA system, pβ-Gal4-p65 and pUAS-Luc were constructed. The pUAS-Luc/pβ-Gal4-p65 system showed the highest transfection efficiency at a 2:1 pUAS-Luc/pβ-Gal4-p65 weight ratio. In addition, the transgene expression by the TSTA system was at least 4 times higher than pβ-Luc. To apply the TSTA system to the GLP-1 expression plasmid, pUAS-GLP-1 was constructed. The pUAS-GLP-1/pβ-Gal4-p65 system showed higher mRNA level than pβ-GLP-1. In addition, the level of GLP-1 by the pUAS-GLP-1/pβ-Gal4-p65 system was more than 4 times higher than pβ-GLP-1. Therefore, the TSTA GLP-1 expression system may be useful to develop gene therapy system for type 2 diabetes. [Copyright &y& Elsevier]

Abstract: Mitochondrial dysfunction may cause diabetes or insulin resistance. Peroxisome proliferation-activated receptor-γ (PPAR-γ) coactivator-1 α (PGC-1α) increases mitochondrial transcription factor A (Tfam) resulting in mitochondrial DNA content increase. An association between a single nucleotide polymorphism (SNP), G1444A(Gly482Ser), of PGC-1α coding region and insulin resistance has been reported in some ethnic groups. In this study, we investigated whether a change of glycine to serine at codon 482 of PGC-1α affected the Tfam promoter activity. The cDNA of PGC-1α variant bearing either glycine or serine at 482 codon was transfected into Chang human hepatocyte cells. The PGC-1α protein bearing glycine had impaired coactivator activity on Tfam promoter-mediated luciferase. We analyzed the PGC-1α genotype G1444A and mitochondrial DNA (mtDNA) copy number from 229 Korean leukocyte genomic DNAs. Subjects with Gly/Gly had a 20% lower amount of peripheral blood mtDNA than did subjects with Gly/Ser and Ser/Ser (p <0.05). No correlation was observed between diabetic parameters and PGC-1α genotypes in Koreans. These results suggest that PGC-1α variants with Gly/Gly at 482nd amino acid may impair the Tfam transcription, a regulatory function of mitochondrial biogenesis, resulting in dysfunctional mtDNA replication. [Copyright &y& Elsevier]

Diabetes mellitus is associated with cardiovascular, ophthalmic, and renal comorbidities. Among these, diabetic cardiomyopathy (DCM) causes the most severe symptoms and is considered to be a major health problem worldwide. Exercise is widely known as an effective strategy for the prevention and treatment of many chronic diseases. Importantly, the onset of complications arising due to diabetes can be delayed or even prevented by exercise. Regular exercise is reported to have positive effects on diabetes mellitus and the development of DCM. The protective effects of exercise include prevention of cardiac apoptosis, fibrosis, oxidative stress, and microvascular diseases, as well as improvement in cardiac mitochondrial function and calcium regulation. This review summarizes the recent scientific findings to describe the potential mechanisms by which exercise may prevent DCM and heart failure. [ABSTRACT FROM AUTHOR]

Tetrahydrobiopterin (BH4) shows therapeutic potential as an endogenous target in cardiovascular diseases. Although it is involved in cardiovascular metabolism and mitochondrial biology, its mechanisms of action are unclear. We investigated how BH4 regulates cardiovascular metabolism using an unbiased multiple proteomics approach with a sepiapterin reductase knock-out (Spr −/−) mouse as a model of BH4 deficiency. Spr −/− mice exhibited a shortened life span, cardiac contractile dysfunction, and morphological changes. Multiple proteomics and systems-based data-integrative analyses showed that BH4 deficiency altered cardiac mitochondrial oxidative phosphorylation. Along with decreased transcription of major mitochondrial biogenesis regulatory genes, including Ppargc1a , Ppara , Esrra , and Tfam , Spr −/− mice exhibited lower mitochondrial mass and severe oxidative phosphorylation defects. Exogenous BH4 supplementation, but not nitric oxide supplementation or inhibition, rescued these cardiac and mitochondrial defects. BH4 supplementation also recovered mRNA and protein levels of PGC1α and its target proteins involved in mitochondrial biogenesis (mtTFA and ERRα), antioxidation (Prx3 and SOD2), and fatty acid utilization (CD36 and CPTI-M) in Spr −/− hearts. These results indicate that BH4-activated transcription of PGC1α regulates cardiac energy metabolism independently of nitric oxide and suggests that BH4 has therapeutic potential for cardiovascular diseases involving mitochondrial dysfunction. Unlabelled Image • BH4 deficiency impairs mitochondrial and cardiac function. • BH4 regulates PGC1α, ERRα, and mtTFA transcription. • BH4 regulates proteins related to mitochondrial antioxidation and fatty acid utilization. • BH4 is essential for mitochondrial biogenesis and oxidative phosphorylation. • BH4 has therapeutic potential for cardiovascular diseases involving mitochondrial dysfunction. [ABSTRACT FROM AUTHOR]

Asprosin, a novel hormone released from white adipose tissue, regulates hepatic glucose metabolism and is pathologically elevated in the presence of insulin resistance. It is unknown whether aerobic exercise training affects asprosin levels in type 1 diabetes mellitus (T1DM). The aim of this study was to determine whether (1) aerobic exercise training could decrease asprosin levels in the liver of streptozotocin (STZ)-induced diabetic rats and (2) the reduction in asprosin levels could induce asprosin-dependent downstream pathways. Five-week-old male Sprague–Dawley rats were randomly divided into control, STZ-induced diabetes (STZ), and STZ with aerobic exercise training groups (n = 6/group). T1DM was induced by a single dose of STZ (65 mg/kg intraperitoneally (i.p.)). The exercise group was made to run on a treadmill for 60 min at a speed of 20 m/min, 4 days per week for 8 weeks. Aerobic exercise training reduced the protein levels of asprosin, PKA, and TGF-β but increased those of AMPK, Akt, PGC-1β, and MnSOD. These results suggest that aerobic exercise training affects hepatic asprosin-dependent PKA/TGF-β and AMPK downstream pathways in T1DM. [ABSTRACT FROM AUTHOR]

Highly efficient and safe gene delivery has become an important aspect of neuronal gene therapy. We evaluated the ability of polyamidoamine (PAMAM) dendrimer grafted with phenylalanine, histidine, and arginine (PAMAM-FHR), a nonviral gene delivery vector, to deliver a therapeutic, tumor cell-specific killer gene, apoptin, into the human primary glioma cell line GBL-14 and human dermal fibroblasts. We performed a transfection assay using plasmids of luciferase and enhanced green fluorescent protein (EGFP) and assessed cell viability. Both cell lines were treated with complexes of PAMAM-FHR and apoptin after which their intracellular uptake and localization were examined by fluorescence-activated cell sorting (FACS)analysis and confocal laser scanning microscopy. Confocal microscopy showed that the PAMAM-FHR escaped from the endo-lysosome into the cytosol. Cell cycle phase distribution analysis, annexin V staining, and a tetramethylrhodamine ethyl ester (TMRE) assay established that apoptin triggered apoptosis in the GBL-14 cell line but not in normal fibroblasts. These results indicated that the PAMAM-FHR/apoptin complex is an effective gene vehicle for cancer therapy in vitro. [ABSTRACT FROM AUTHOR]

The heterodimer of human ubiquitin fusion degradation 1 (hUfd1) and human nuclear protein localization 4 (hNpl4) is a major cofactor of human p97 adenosine triphosphatase (ATPase). The p97-Ufd1-Npl4 complex translocates the ubiquitin-conjugated proteins from the endoplasmic reticulum membrane to the cytoplasm. Ubiquitinated proteins are then degraded by the proteasome. The structures of Npl4 and Ufd1-Npl4 (UN) complex in Saccharomyces cerevisiae have been recently reported; however, the structures of hNpl4 and the human UN complex remain unknown. Here, we report the crystal structures of the human UN complex at a resolution of 2.7 Å and hNpl4 at a resolution of 3.0 Å. We also present atomic details and characterization of the human UN complex. Crystallographic studies and site-directed mutagenesis of the hUfd1 residues involved in the interaction with hNpl4 revealed the atomic details of the two proteins., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Recent trends suggest novel natural compounds as promising treatments for cardiovascular disease. The authors examined how neopetroside A, a natural pyridine nucleoside containing an α-glycoside bond, regulates mitochondrial metabolism and heart function and investigated its cardioprotective role against ischemia/reperfusion injury. Neopetroside A treatment maintained cardiac hemodynamic status and mitochondrial respiration capacity and significantly prevented cardiac fibrosis in murine models. These effects can be attributed to preserved cellular and mitochondrial function caused by the inhibition of glycogen synthase kinase-3 beta, which regulates the ratio of nicotinamide adenine dinucleotide to nicotinamide adenine dinucleotide, reduced, through activation of the nuclear factor erythroid 2-related factor 2/NAD(P)H quinone oxidoreductase 1 axis in a phosphorylation-independent manner., Competing Interests: This work was supported by the Basic Science Research Program (NRF-2020R1A4A1018943 and NRF-2018R1A2A3074998) through the National Research Foundation of Korea, funded by the Ministry of Education and the Ministry of Science and ICT. The synthesis of NPS A was supported by the Russian Science Foundation (grant 19-73-30017). The authors have reported that they have no relationships relevant to the contents of this paper to disclose., (© 2022 The Authors.)

Aims: Cereblon (CRBN) is a substrate receptor of the E3 ubiquitin ligase complex that was reported to target ion channel proteins. L-type voltage-dependent Ca2+ channel (LTCC) density and dysfunction is a critical player in heart failure with reduced ejection fraction (HFrEF). However, the underlying cellular mechanisms by which CRBN regulates LTCC subtype Cav1.2α during cardiac dysfunction remain unclear. Here, we explored the role of CRBN in HFrEF by investigating the direct regulatory role of CRBN in Cav1.2α activity and examining how it can serve as a target to address myocardial dysfunction., Methods and Results: Cardiac tissues from HFrEF patients exhibited increased levels of CRBN compared with controls. In vivo and ex vivo studies demonstrated that whole-body CRBN knockout (CRBN-/-) and cardiac-specific knockout mice (Crbnfl/fl/Myh6Cre+) exhibited enhanced cardiac contractility with increased LTCC current (ICaL) compared with their respective controls, which was modulated by the direct interaction of CRBN with Cav1.2α. Mechanistically, the Lon domain of CRBN directly interacted with the N-terminal of Cav1.2α. Increasing CRBN levels enhanced the ubiquitination and proteasomal degradation of Cav1.2α and decreased ICaL. In contrast, genetic or pharmacological depletion of CRBN via TD-165, a novel PROTAC-based CRBN degrader, increased surface expression of Cav1.2α and enhanced ICaL. Low CRBN levels protected the heart against cardiomyopathy in vivo., Conclusion: Cereblon selectively degrades Cav1.2α, which in turn facilitates cardiac dysfunction. A targeted approach or an efficient method of reducing CRBN levels could serve as a promising strategy for HFrEF therapeutics., (© The Author(s) 2022. Published by Oxford University Press on behalf of European Society of Cardiology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The development of selective targeting of drug molecules towards the mitochondria is an important issue related to therapy efficacy. In this study, we report that gallic acid (GA)-mitochondria targeting sequence (MTS)-H 3 R 9 exhibits a dual role as a mitochondria-targeting vehicle with antioxidant activity for disease therapy. In viability assays, GA-MTS-H 3 R 9 showed a better rescue action compared to that of MTS-H 3 R 9 . GA-MTS-H 3 R 9 dramatically exhibited cell penetration and intercellular uptake compared to MTS and fit escape from lysosome release to the cytosol. We demonstrated the useful targeting of GA-MTS-H 3 R 9 towards mitochondria in AC16 cells. Also, we observed that the antioxidant properties of mitochondrial-accrued GA-MTSH 3 R 9 alleviated cell damage by reactive oxygen species production and disrupted mitochondrial membrane potential. GA-MTS-H 3 R 9 showed a very increased cytoprotective effect against anticancer activity compared to that of MTS-H 3 R 9 . We showed that GA-MTS-H 3 R 9 can act as a vehicle for mitochondria-targeting and as a reagent for therapeutic applications intended for cardiovascular disease treatment.

Atopic dermatitis (AD) is a chronic inflammatory skin disease in which skin barrier dysfunction leads to dryness, pruritus, and erythematous lesions. AD is triggered by immune imbalance and oxidative stress. Echinochrome A (Ech A), a natural pigment isolated from sea urchins, exerts antioxidant and beneficial effects in various inflammatory disease models. In the present study, we tested whether Ech A treatment alleviated AD-like skin lesions. We examined the anti-inflammatory effect of Ech A on 2,4-dinitrochlorobenzene (DNCB)-induced AD-like lesions in an NC/Nga mouse model. AD-like skin symptoms were induced by treatment with 1% DNCB for 1 week and 0.4% DNCB for 5 weeks in NC/Nga mice. The results showed that Ech A alleviated AD clinical symptoms, such as edema, erythema, and dryness. Treatment with Ech A induced the recovery of epidermis skin lesions as observed histologically. Tewameter ® and Corneometer ® measurements indicated that Ech A treatment reduced transepidermal water loss and improved stratum corneum hydration, respectively. Ech A treatment also inhibited inflammatory-response-induced mast cell infiltration in AD-like skin lesions and suppressed the expression of proinflammatory cytokines, such as interferon-γ, interleukin-4, and interleukin-13. Collectively, these results suggest that Ech A may be beneficial for treating AD owing to its anti-inflammatory effects.

Purpose: To evaluate the effects of glycemic variability on the progression of diabetic retinopathy (DR) among individuals with Type 2 diabetes and to test the hypothesis that consistent glycemic control delays the progression of DR., Methods: This retrospective study included 1,125 participants with a follow-up period of more than 5 years and more than 20 glucose laboratory test results. The hazard ratio of ≥3 steps of progression on the Early Treatment Diabetic Retinopathy Study person scale and progression to proliferative DR were assessed., Results: An increase in the HbA1c SD was associated with a higher risk of ≥3 step progression (P < 0.001) and progression to proliferative DR (P < 0.001). Not only mean HbA1c, but also HbA1c SD was associated with a lower risk of ≥3 steps of progression (P < 0.001), and progression to proliferative DR (P < 0.001)., Conclusion: Achievable and consistent glycemic control may contribute to the delay in DR progression., Clinical Trial Registration Number: Institutional review board of Inje University (No. 202003014).

Diabetic cardiomyopathy (DCM) is a major cause of mortality/morbidity in diabetes mellitus patients. Although tetrahydrobiopterin (BH4) shows therapeutic potential as an endogenous cardiovascular target, its effect on myocardial cells and mitochondria in DCM and the underlying mechanisms remain unknown. Here, we determined the involvement of BH4 deficiency in DCM and the therapeutic potential of BH4 supplementation in a rodent DCM model. We observed a decreased BH4:total biopterin ratio in heart and mitochondria accompanied by cardiac remodeling, lower cardiac contractility, and mitochondrial dysfunction. Prolonged BH4 supplementation improved cardiac function, corrected morphological abnormalities in cardiac muscle, and increased mitochondrial activity. Proteomics analysis revealed oxidative phosphorylation (OXPHOS) as the BH4-targeted biological pathway in diabetic hearts as well as BH4-mediated rescue of down-regulated peroxisome proliferator-activated receptor-γ coactivator 1-α (PGC-1α) signaling as a key modulator of OXPHOS and mitochondrial biogenesis. Mechanistically, BH4 bound to calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2) and activated downstream AMP-activated protein kinase/cAMP response element binding protein/PGC-1α signaling to rescue mitochondrial and cardiac dysfunction in DCM. These results suggest BH4 as a novel endogenous activator of CaMKK2., (© 2020 Kim et al.)

Objective: We assessed the associations of percentage fractions of urinary di(2-ethylhexyl) phthalate (DEHP) metabolites with obesity and insulin resistance in Korean girls., Methods: In total, 137 girls, aged 6 to 13 years (65 overweight cases and 72 controls), were recruited. Anthropometric indices and the homeostatic model assessment of insulin resistance (HOMA-IR) index were determined. Four major urinary DEHP metabolites were analyzed in spot urine samples by gas chromatography-tandem mass spectrometry, including mono(2-ethylhexyl) phthalate, mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), and mono(2-ethyl-5-carboxypentyl) phthalate., Results: There were no significant differences in the urinary concentrations of the DEHP metabolites between the overweight and control groups. The percentage fraction of MEHHP (MEHHP%) among all DEHP metabolites was significantly higher in the overweight prepubertal girls than in the controls (P = 0.035). MEHHP% was positively associated with the body mass index percentile, waist circumference, body fat percentage, and HOMA-IR index in the prepubertal girls. After adjusting for covariates, the prepubertal girls in a higher MEHHP% quartile were found to have a higher odds ratio for central obesity than those in a lower quartile (odds ratios: 5.05 for quartile 3; 7.30 for quartile 4). The relative rate of MEHHP oxidation to MEOHP was negatively associated with the body mass index percentile and waist circumference in the prepubertal girls. However, no such association was observed in the pubertal girls., Conclusions: MEHHP% was positively associated with obesity and insulin resistance in prepubertal girls. Further studies are necessary to elucidate the causal links between altered phthalate metabolism and increased susceptibility to insulin resistance in children., Competing Interests: The authors have declared that no competing interests exist.

Unlike stable and immobile cell line conditions, animal hearts contract and relax to pump blood throughout the body. Mitochondria play an essential role by producing biological energy molecules to maintain heart function. In this study, we assessed the effect of heart mimetic cyclic stretch on mitochondria in a cardiac cell line. To mimic the geometric and biomechanical conditions surrounding cells in vivo, cyclic stretching was performed on HL-1 murine cardiomyocytes seeded onto an elastic micropatterned substrate (10% elongation, 0.5 Hz, 4 h/day). Cell viability, semi-quantitative Q-PCR, and western blot analyses were performed in non-stimulated control and cyclic stretch stimulated HL-1 cell lines. Cyclic stretch significantly increased the expression of mitochondria biogenesis-related genes (TUFM, TFAM, ERRα, and PGC1-α) and mitochondria oxidative phosphorylation-related genes (PHB1 and CYTB). Western blot analysis confirmed that cyclic stretch increased protein levels of mitochondria biogenesis-related proteins (TFAM, and ERRα) and oxidative phosphorylation-related proteins (NDUFS1, UQCRC, and PHB1). Consequently, cyclic stretch increased mitochondrial mass and ATP production in treated cells. Our results suggest that cyclic stretch transcriptionally enhanced mitochondria biogenesis and oxidative phosphorylation without detrimental effects in a cultured cardiac cell line., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Multiple myeloma (MM) is a neoplastic plasma cell disorder with high disease recurrence rates. Novel therapeutic approaches capable of improving outcomes in patients with MM are urgently required. The AKT signalling plays a critical regulatory role in MM pathophysiology, including survival, proliferation, metabolism, and has emerged as a key therapeutic target. Here, we identified a novel AKT inhibitor, HS1793, and defined its mechanism of action and clinical significance in MM. HS1793 disrupted the interaction between AKT and heat shock protein 90, resulting in protein phosphatase 2A-modulated phosphorylated-AKT (p-AKT) reduction. Moreover, we observed reductions in the kinase activity of the AKT downstream target, IκB kinase alpha, and the transcriptional activity of nuclear factor kappa B, which induced mitochondria-mediated cell death in MM cells exclusively. We confirmed the cytotoxicity and specificity of HS1793 via PET-CT imaging of a metastatic mouse model generated using human MM cells. We also evaluated the cytotoxic effects of HS1793 in primary and relapsed MM cells isolated from patients. Thus, HS1793 offers great promise in eliminating MM cells and improving therapeutic responses in primary and relapsed/refractory MM patients., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Three-dimensional (3D) computational aortic models have been established to reproduce aortic diseases such as aortic aneurysm and dissection; however, no such models have been developed to study diabetes mellitus (DM). To characterize biomechanical properties of the human aorta with DM, reconstructed aortic CT images were converted into DICOM format, and imported into the 3D segmentation using Mimics software. This resulted in a 3D reconstruction of the complete aorta, including three branches. We applied a pulsatile blood pressure waveform for the ascending aorta to provide a biomimetic environment using COMSOL Multiphysics software. Hemodynamics were compared between the control and DM models. We observed that mean blood flow velocity, aortic pressure, and von Mises stress values were lower in the DM model than in the control model. Furthermore, the range of aortic movement was lower in the DM model than in the control model, suggesting that the DM aortic wall is more susceptible to rupture. When comparing biomechanical properties in discrete regions of the aorta, all values were higher in the ascending aorta for both control and DM models, corresponding to the location of most aortic lesions. We have developed a compute based that integrates advanced image processing strategies and computational techniques based on finite element method to perform hemodynamics analysis based on CT images. Our study of image-based CFD analysis hopes to provide a better understanding of the relationship between aortic hemodynamic and developing pathophysiology of aortic diseases., Competing Interests: The authors have declared that no competing interests exist.

Purpose: Aging changes the balance of sex hormones and causes endothelial dysfunction in the penis, both of which are important determinants of erectile dysfunction (ED). The purpose of this study was to evaluate whether exercise training could protect against erectile dysfunction by increasing serum testosterone and penile eNOS levels in aging rats., Methods: A total of 14 young (2-month-old) and 14 middle-aged (18-month-old) Sprague Dawley rats were randomly assigned to either untrained control (young control, [YC], middle-aged control, [MC]) or endurance exercise-trained (young exercise, [YE], middle-aged exercise, [ME]) groups with seven rats per group. The exercise groups trained with treadmill running for 6 weeks. Body composition parameters (body weight, heart mass, liver mass, and testicular mass), serum sex hormone levels (testosterone, luteinizing hormone, follicle-stimulating hormone, and prolactin), endothelial function-related parameters in the penis (endothelial nitric oxide synthase [eNOS], CD31, alpha smooth muscle actin [α-SMA]), and maximal intracavernous pressure measure (ICP) and total ICP were analyzed in middle-aged rats., Results: The middle-aged groups showed increased body weight, as compared with the young groups, but exercise training attenuated the aging-induced increase in body weight. The middle-aged groups had lower testicular mass compared with the young groups, but exercise training attenuated aging-induced decreases in testicular mass. Exercise training increased serum testosterone levels in both the young and middle-aged groups. However, there were no changes in the levels of luteinizing hormone, follicle-stimulating hormone, and prolactin among the groups. MC group showed decreased protein levels of p-eNOS, as compared with the YC group. However, exercise training protected against aging-induced decrease in eNOS and p-eNOS protein levels in the penis. Interestingly, exercise training also increased protein levels of α-SMA and maximal ICP in the middle-aged group., Conclusions: Exercise training has beneficial effects on erectile function in aged rats through increased testosterone production from the testis and strengthening of the cavernous endothelium with activation of eNOS. Therefore, exercise training may be a therapeutic modality for improving erectile dysfunction associated with aging., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Alternative splicing (AS) of protein-coding messenger RNAs is an essential regulatory mechanism in eukaryotic gene expression that controls the proper function of proteins. It is also implicated in the physiological regulation of mitochondria and various ion channels. Considering that mis-splicing can result in various human diseases by modifying or abrogating important physiological protein functions, a fine-tuned balance of AS is essential for human health. Accumulated data highlight the importance of alternatively spliced isoforms in various diseases, including neurodegenerative disorders, cancer, immune and infectious diseases, cardiovascular diseases, and metabolic conditions. However, basic understanding of disease mechanisms and development of clinical applications still require the integration and interpretation of physiological roles of AS. This review discusses the roles of AS in health and various diseases, while highlighting potential AS-targeting therapeutic applications.

Ursolic acid (UA) is a natural triterpene compound found in various fruits and vegetables. There is a growing interest in UA because of its beneficial effects, which include anti-inflammatory, anti-oxidant, anti-apoptotic, and anti-carcinogenic effects. It exerts these effects in various tissues and organs: by suppressing nuclear factor-kappa B signaling in cancer cells, improving insulin signaling in adipose tissues, reducing the expression of markers of cardiac damage in the heart, decreasing inflammation and increasing the level of anti-oxidants in the brain, reducing apoptotic signaling and the level of oxidants in the liver, and reducing atrophy and increasing the expression levels of adenosine monophosphate-activated protein kinase and irisin in skeletal muscles. Moreover, UA can be used as an alternative medicine for the treatment and prevention of cancer, obesity/diabetes, cardiovascular disease, brain disease, liver disease, and muscle wasting (sarcopenia). In this review, we have summarized recent data on the beneficial effects and possible uses of UA in health and disease managements., Competing Interests: CONFLICTS OF INTEREST: The authors declare no conflicts of interest.

Korea's National Healthcare Program, the National Health Insurance Service (NHIS), a government-affiliated agency under the Korean Ministry of Health and Welfare, covers the entire Korean population. The NHIS supervises all medical services in Korea and establishes a systematic National Health Information database (DB). A health information DB system including all of the claims, medications, death information, and health check-ups, both in the general population and in patients with various diseases, is not common worldwide. On June 9, 2014, the NHIS signed a memorandum of understanding with the Korean Diabetes Association (KDA) to provide limited open access to its DB. By October 31, 2017, seven papers had been published through this collaborative research project. These studies were conducted to investigate the past and current status of type 2 diabetes mellitus and its complications and management in Korea. This review is a brief summary of the collaborative projects between the KDA and the NHIS over the last 3 years. According to the analysis, the national health check-up DB or claim DB were used, and the age category or study period were differentially applied., Competing Interests: No potential conflict of interest relevant to this article was reported., (Copyright © 2018 Korean Diabetes Association.)

Mitochondria are targets with great potential for therapeutics for many human disorders. However, drug delivery systems for such therapeutics remain in need of more efficient mitochondrial-targeting carriers. In this study, we report that nanosomes composed of Dequalinium/DOTAP (1,2-dioleoyl-3-trimethylammonium-propane)/DOPE (1,2-dioleoyl-sn-glycero-3-phosphoethanolamine), called DQA80s, can act in the dual role of mitochondrial-targeting carrier and anticancer agent for therapeutic interventions against mitochondrial diseases. In cytotoxicity assays, DQA80s were shown to be more toxic than DQAsomes. The DQA80s showed significantly increased cellular uptake as compared to that of DQAsomes, and DQA80s also showed more efficient escape from the endolysosome to the cytosol. We observed the efficient targeting of DQA80s to mitochondria in living cells using flow cytometry, confocal microscopy, and TEM imaging. We also found evidence of anticancer potential that mitochondrial-targeted DQA80s induced apoptosis by production of reactive oxygen species (ROS) via MAPK signaling pathways, loss of mitochondrial membrane potential, and the caspase-3 activation. The present study demonstrates that DQA80s have excellent dual potential both as a carrier and as an anticancer therapeutic for mitochondria-related disease therapy in vivo., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Metabolic disturbance and mitochondrial dysfunction are a hallmark of diabetic cardiomyopathy (DC). Resistance exercise (RE) not only enhances the condition of healthy individuals but could also improve the status of those with disease. However, the beneficial effects of RE in the prevention of DC and mitochondrial dysfunction are uncertain. Therefore, this study investigated whether RE attenuates DC by improving mitochondrial function using an in vivo rat model of diabetes. Fourteen Otsuka Long-Evans Tokushima Fatty rats were assigned to sedentary control (SC, n = 7) and RE (n = 7) groups at 28 weeks of age. Long-Evans Tokushima Otsuka rats were used as the non-diabetic control. The RE rats were trained by 20 repetitions of climbing a ladder 5 days per week. RE rats exhibited higher glucose uptake and lower lipid profiles, indicating changes in energy metabolism. RE rats significantly increased the ejection fraction and fractional shortening compared with the SC rats. Isolated mitochondria in RE rats showed increase in mitochondrial numbers, which were accompanied by higher expression of mitochondrial biogenesis proteins such as proliferator-activated receptor-γ coactivator-1α and TFAM. Moreover, RE rats reduced proton leakage and reactive oxygen species production, with higher membrane potential. These results were accompanied by higher superoxide dismutase 2 and lower uncoupling protein 2 (UCP2) and UCP3 levels in RE rats. These data suggest that RE is effective at ameliorating DC by improving mitochondrial function, which may contribute to the maintenance of diabetic cardiac contractility.

Mitochondria are essential intracellular organelles that regulate energy metabolism, cell death, and signaling pathways that are important for cell proliferation and differentiation. Therefore, mitochondria are fundamentally implicated in cancer biology, including initiation, growth, metastasis, relapse, and acquired drug resistance. Based on these implications, mitochondria have been proposed as a major therapeutic target for cancer treatment. In addition to classical view of mitochondria in cancer biology, recent studies found novel pathophysiological roles of mitochondria in cancer. In this review, we introduce recent concepts of mitochondrial roles in cancer biology including mitochondrial DNA mutation and epigenetic modulation, energy metabolism reprogramming, mitochondrial channels, involvement in metastasis and drug resistance, and cancer stem cells. We also discuss the role of mitochondria in emerging cancer therapeutic strategies, especially cancer immunotherapy and CRISPR-Cas9 system gene therapy., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Mitochondria dysfunction plays a role in many human diseases. Therapeutic techniques for these disorders require novel delivery systems that can specifically target and penetrate mitochondria. In this study, we report a novel nanosome composed of dequalinium-DOTAP-DOPE (1,2 dioleoyl-3-trimethylammonium-propane-1,2-dioleoyl-sn-glycero-3-phosphoethanolamine) (DQA80s) as a potential mitochondria-targeting delivery vector. The functional DQAsome, DQA80s, showed enhanced transfection efficiency compared to a vector DQAsomes in HeLa cells and dermal fibroblasts. In addition, DQA80s/pDNA complexes exhibited rapid escape from the endosome into the cytosol. We observed the delivery of pDNA to mitochondria in living cells using flow cytometry, confocal microscopy, and TME imaging. More specifically, we confirmed our results by co-localization of hmtZsGreen constructs to mitochondria when delivered via DQAsomes and DQA80s in living cells. The mitochondria-targeting DQAsomes and DQA80s induced mitochondrial dysfunction through depolarization of mitochondrial membrane potential. Our data demonstrate that DQA80s show promise for use as a mitochondria-targeted carrier system for treatment of mitochondria diseases in vivo., (Copyright © 2017. Published by Elsevier B.V.)

Rational: Kallmann syndrome (KS) is a genetic gonadotropin-releasing hormone deficiency associated with hyposmia or anosmia and characterized by various modes of inheritance., Patient Concerns: A 16-year-old male did not reach puberty and was associated with hypogonadotropic hypogonadism and anosmia. His magnetic resonance imaging of brain revealed the absence of the olfactory bulb., Diagnosis: His karyotype was 46 XY. Sanger sequencing of the KAL1 gene revealed no mutations. Diagnostic exome sequencing identified a prokineticin-receptor 2 (PROKR2) gene variant, c.337T > C (p.Tyr113His), previously reported to be a pathogenic mutation; we confirmed the presence of the mutation via Sanger sequencing of the coding exons of PROKR2. His apparently unaffected mother and sister, but not his father, were heterozygous for the PROKR2 Tyr113His mutation., Lessons: This work advances our understanding of the role played by PROKR signaling and the mode of inheritance of the gene in patients with KS.

Background: Previous reports have demonstrated a bidirectional relationship between depression and diabetes mellitus (DM), accentuating a need for more intensive depression screening in DM patients. There is a relative paucity of data on the mortality of depressed DM patients in Korea., Methods: Retrospective data from January 2003 to December 2013 were collected for adult type 2 diabetes mellitus (T2DM) patients older than 30 years using the National Health Information database maintained by the Korean National Health Insurance Service (NHIS). Demographic characteristics were analyzed with descriptive statistics, and the annual prevalence of depression was estimated. Mortality rates and hazard ratios for each age group (stratified into six age groups) of patients diagnosed with T2DM in 2003 were estimated using a Cox proportional hazard method, with the Kaplan-Meier cumulative survival curve showing the overall survival rates according to the T2DM status until the given year of 2013., Results: The annual prevalence of depression was consistently higher in T2DM group from 2003 to 2013. The mortality hazard ratio was higher in the depressed in all age groups, and the risk was higher in male groups and in younger-aged groups., Conclusion: Depression was significantly associated with a high mortality risk in T2DM patients; hence, a more systematic surveillance of T2DM patients to identify risk factors for depression might contribute significantly to reducing mortality risk in this group of patients., Competing Interests: No potential conflict of interest relevant to this article was reported., (Copyright © 2017 Korean Diabetes Association)

Malignant glioma is the most common and aggressive form of primary brain tumor in adults. In this study, we describe the efficacy of nonviral gene delivery carriers, histidine- and arginine- or histidine- and lysine-grafted polyamidoamine (PAMAM) dendrimers (PAMAM-H-R and PAMAM-H-K), in delivering a therapeutic and a tumor-selective killer gene, apoptin, using human glioma cells (U87-MG) and newborn human dermal fibroblast cells. We analyzed transfection efficiency using luciferase and a plasmid DNA encoding for enhanced green fluorescent protein and assessed cell viability in both cells. The results show that transfection efficiency of PAMAM-H-R and PAMAM-H-K was greatly increased compared with that of native PAMAM. Moreover, among PAMAM derivatives, cytotoxicity of PAMAM-H-K was very low. We treated both cells with complexes of PAMAM-H-R or PAMAM-H-K and apoptin and analyzed their cellular uptake by flow cytometry and localization by confocal microscopy. Furthermore, cell cycle distribution, caspase 3 activity assay, and JC-1 analysis showed cell death induced by apoptin in U87-MG cells. The present study demonstrates that a PAMAM-H-R/apoptin complex is an effective gene carrier system in glioma cell culture., (Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.)