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Mitochondrial dysfunction in white adipose tissue is strongly associated with obesity and its metabolic complications, which are important health challenges worldwide. Human adipose-derived stromal/stem cells (hASCs) are a promising tool to investigate the underlying mechanisms of such mitochondrial dysfunction and to subsequently provide knowledge for the development of treatments for obesity-related pathologies. A substantial obstacle in using hASCs is that the key compounds for adipogenic differentiation in vitro increase mitochondrial uncoupling, biogenesis, and activity, which are the signature features of brown adipocytes, thus altering the white adipocyte phenotype towards brown-like cells. Additionally, commonly used protocols for hASC adipogenic differentiation exhibit high variation in their composition of media, and a systematic comparison of their effect on mitochondria is missing. Here, we compared the five widely used adipogenic differentiation protocols for their effect on metabolic and mitochondrial phenotypes to identify a protocol that enables in vitro differentiation of white adipocytes and can more faithfully recapitulate the white adipocyte phenotype observed in human adipose tissue. We developed a workflow that included functional assays and morphological analysis of mitochondria and lipid droplets. We observed that triiodothyronine- or indomethacin-containing media and commercially available adipogenic media induced browning during in vitro differentiation of white adipocytes. However, the differentiation protocol containing 1  μ M of the peroxisome proliferator-activated receptor gamma (PPAR γ ) agonist rosiglitazone prevented the browning effect and would be proposed for adipogenic differentiation protocol for hASCs to induce a white adipocyte phenotype. Preserving the white adipocyte phenotype in vitro is a crucial step for the study of obesity and associated metabolic diseases, adipose tissue pathologies, such as lipodystrophies, possible therapeutic compounds, and basic adipose tissue physiology., Competing Interests: The authors declare that there are no conflicts of interest regarding the publication of this manuscript., (Copyright © 2022 Elena Herbers et al.)

Context: Mitochondria are essential for cellular energy homeostasis, yet their role in subcutaneous adipose tissue (SAT) during different types of weight-loss interventions remains unknown., Objective: To investigate how SAT mitochondria change following diet-induced and bariatric surgery-induced weight-loss interventions in 4 independent weight-loss studies., Methods: The DiOGenes study is a European multicenter dietary intervention with an 8-week low caloric diet (LCD; 800 kcal/d; n = 261) and 6-month weight-maintenance (n = 121) period. The Kuopio Obesity Surgery study (KOBS) is a Roux-en-Y gastric bypass (RYGB) surgery study (n = 172) with a 1-year follow-up. We associated weight-loss percentage with global and 2210 mitochondria-related RNA transcripts in linear regression analysis adjusted for age and sex. We repeated these analyses in 2 studies. The Finnish CRYO study has a 6-week LCD (800-1000 kcal/d; n = 19) and a 10.5-month follow-up. The Swedish DEOSH study is a RYGB surgery study with a 2-year (n = 49) and 5-year (n = 37) follow-up., Results: Diet-induced weight loss led to a significant transcriptional downregulation of oxidative phosphorylation (DiOGenes; ingenuity pathway analysis [IPA] z-scores: -8.7 following LCD, -4.4 following weight maintenance; CRYO: IPA z-score: -5.6, all P < 0.001), while upregulation followed surgery-induced weight loss (KOBS: IPA z-score: 1.8, P < 0.001; in DEOSH: IPA z-scores: 4.0 following 2 years, 0.0 following 5 years). We confirmed an upregulated oxidative phosphorylation at the proteomics level following surgery (IPA z-score: 3.2, P < 0.001)., Conclusions: Differentially regulated SAT mitochondria-related gene expressions suggest qualitative alterations between weight-loss interventions, providing insights into the potential molecular mechanistic targets for weight-loss success., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society.)

Tissue-specific mechanisms prompting obesity-related development complications in humans remain unclear. We apply multiomics analyses of subcutaneous adipose tissue and skeletal muscle to examine the effects of acquired obesity among 49 BMI-discordant monozygotic twin pairs. Overall, adipose tissue appears to be more affected by excess body weight than skeletal muscle. In heavier co-twins, we observe a transcriptional pattern of downregulated mitochondrial pathways in both tissues and upregulated inflammatory pathways in adipose tissue. In adipose tissue, heavier co-twins exhibit lower creatine levels; in skeletal muscle, glycolysis- and redox stress-related protein and metabolite levels remain higher. Furthermore, metabolomics analyses in both tissues reveal that several proinflammatory lipids are higher and six of the same lipid derivatives are lower in acquired obesity. Finally, in adipose tissue, but not in skeletal muscle, mitochondrial downregulation and upregulated inflammation are associated with a fatty liver, insulin resistance, and dyslipidemia, suggesting that adipose tissue dominates in acquired obesity., Competing Interests: The authors declare no competing interests., (© 2021 The Authors.)

White adipose tissue is one of the largest organs of the body. It plays a key role in whole-body energy status and metabolism; it not only stores excess energy but also secretes various hormones and metabolites to regulate body energy balance. Healthy adipose tissue capable of expanding is needed for metabolic well-being and to prevent accumulation of triglycerides to other organs. Mitochondria govern several important functions in the adipose tissue. We review the derangements of mitochondrial function in white adipose tissue in the obese state. Downregulation of mitochondrial function or biogenesis in the white adipose tissue is a central driver for obesity-associated metabolic diseases. Mitochondrial functions compromised in obesity include oxidative functions and renewal and enlargement of the adipose tissue through recruitment and differentiation of adipocyte progenitor cells. These changes adversely affect whole-body metabolic health. Dysfunction of the white adipose tissue mitochondria in obesity has long-term consequences for the metabolism of adipose tissue and the whole body. Understanding the pathways behind mitochondrial dysfunction may help reveal targets for pharmacological or nutritional interventions that enhance mitochondrial biogenesis or function in adipose tissue., (© 2019 World Obesity Federation.)

Purpose: The purpose of this study is to elucidate the effect of excess body weight and liver fat on the plasma proteome without interference from genetic variation., Experimental Design: The effect of excess body weight is assessed in young, healthy monozygotic twins from pairs discordant for body mass index (intrapair difference (Δ) in BMI > 3 kg m -2 , n = 26) with untargeted LC-MS proteomics quantification. The effect of liver fat is interrogated via subgroup analysis of the BMI-discordant twin cohort: liver fat discordant pairs (Δliver fat > 2%, n = 12) and liver fat concordant pairs (Δliver fat < 2%, n = 14), measured by magnetic resonance spectroscopy., Results: Seventy-five proteins are differentially expressed, with significant enrichment for complement and inflammatory response pathways in the heavier co-twins. The complement dysregulation is found in obesity in both the liver fat subgroups. The complement and inflammatory proteins are significantly associated with adiposity measures, insulin resistance and impaired lipids., Conclusions and Clinical Relevance: The early pathophysiological mechanisms in obesity are incompletely understood. It is shown that aberrant complement regulation in plasma is present in very early stages of clinically healthy obese persons, independently of liver fat and in the absence of genetic variation that typically confounds human studies., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: Neurotransmitter substance P (SP) and its preferred neurokinin-1 receptor (NK1R) have been implicated in the treatment of affective and addiction disorders. Despite promising preclinical data on antidepressant action, the clinical trials of NK1R antagonists in major depression have been disappointing. There are no direct in vivo imaging studies on NK1R characteristics in patients with a major depressive disorder (MDD)., Methods: In this cross-sectional case-control study, we recruited nine never-medicated patients with moderate to severe MDD and nine matched healthy controls. NK1R availability (NK1R binding potential, BP ND ) was measured with in vivo 3-D positron emission tomography and a specific NK1 receptor tracer [ 18 F]SPA-RQ. Clinical symptoms were assessed with the 17-item Hamilton Rating Scale for Depression (HAM-D17)., Results: NK1R-BP ND did not differ statistically significantly between patients with MDD and healthy controls. HAM-D17 total scores (range 21-32) correlated positively with NK1R-BP ND in cortical and limbic areas. HAM-D17 subscale score for anxiety symptoms correlated positively with NK1R-BP ND in specific brain areas implicated in fear and anxiety., Limitations: Small sample size. Low variability in the clinical HAM-D subscale ratings may affect the observed correlations., Conclusions: Our preliminary results do not support a different baseline expression of NK1Rs in a representative sample of never-medicated patients with MDD during a current moderate/severe depressive episode. The modulatory effect of NK1Rs on affective symptoms is in line with early positive results on antidepressant action of NK1 antagonists. However, the effect is likely to be too weak for treatment of MDD with NK1R antagonists alone in clinical practice., (Copyright © 2018. Published by Elsevier B.V.)

Obesity, a chronic state of energy overload, is characterized by adipose tissue dysfunction that is considered to be the major driver for obesity associated metabolic complications. The reasons for adipose tissue dysfunction are incompletely understood, but one potential contributing factor is adipose tissue mitochondrial dysfunction. Derangements of adipose tissue mitochondrial biogenesis and pathways associate with obesity and metabolic diseases. Mitochondria are central organelles in energy metabolism through their role in energy derivation through catabolic oxidative reactions. The mitochondrial processes are dependent on the proper NAD + /NADH redox balance and NAD + is essential for reactions catalyzed by the key regulators of mitochondrial metabolism, sirtuins (SIRTs) and poly(ADP-ribose) polymerases (PARPs). Notably, obesity is associated with disturbed adipose tissue NAD + homeostasis and the balance of SIRT and PARP activities. In this review we aim to summarize existing literature on the maintenance of intracellular NAD + pools and the function of SIRTs and PARPs in adipose tissue during normal and obese conditions, with the purpose of comprehending their potential role in mitochondrial derangements and obesity associated metabolic complications. Understanding the molecular mechanisms that are the root cause of the adipose tissue mitochondrial derangements is crucial for developing new effective strategies to reverse obesity associated metabolic complications., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)

Mitochondria are dynamic organelles that divide and fuse by remodeling an outer and inner membrane in response to developmental, physiological and stress stimuli. These events are coordinated by conserved dynamin-related GTPases. The dynamics of mitochondrial morphology require coordination with mitochondrial DNA (mtDNA) to ensure faithful genome transmission, however, this process remains poorly understood. Mitochondrial division is linked to the segregation of mtDNA but how it affects cases of mtDNA heteroplasmy, where two or more mtDNA variants/mutations co-exist in a cell, is unknown. Segregation of heteroplasmic human pathogenic mtDNA mutations is a critical factor in the onset and severity of human mitochondrial diseases. Here, we investigated the coupling of mitochondrial morphology to the transmission and segregation of mtDNA in mammals by taking advantage of two genetically modified mouse models: one with a dominant-negative mutation in the dynamin-related protein 1 (Drp1 or Dnm1l) that impairs mitochondrial fission and the other, heteroplasmic mice segregating two neutral mtDNA haplotypes (BALB and NZB). We show a tissue-specific response to mtDNA segregation from a defect in mitochondrial fission. Only mtDNA segregation in the hematopoietic compartment is modulated from impaired Dnm1l function. In contrast, no effect was observed in other tissues arising from the three germ layers during development and in mtDNA transmission through the female germline. Our data suggest a robust organization of a heteroplasmic mtDNA segregating unit across mammalian cell types that can overcome impaired mitochondrial division to ensure faithful transmission of the mitochondrial genome., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Mammalian mitochondrial DNA (mtDNA) is a high-copy maternally inherited genome essential for aerobic energy metabolism. Mutations in mtDNA can lead to heteroplasmy, the co-occurence of two different mtDNA variants in the same cell, which can segregate in a tissue-specific manner affecting the onset and severity of mitochondrial dysfunction. To investigate mechanisms regulating mtDNA segregation we use a heteroplasmic mouse model with two polymorphic neutral mtDNA haplotypes (NZB and BALB) that displays tissue-specific and age-dependent selection for mtDNA haplotypes. In the hematopoietic compartment there is selection for the BALB mtDNA haplotype, a phenotype that can be modified by allelic variants of Gimap3. Gimap3 is a tail-anchored member of the GTPase of the immunity-associated protein (Gimap) family of protein scaffolds important for leukocyte development and survival. Here we show how the expression of two murine Gimap3 alleles from Mus musculus domesticus and M. m. castaneus differentially affect mtDNA segregation. The castaneus allele has incorporated a uORF (upstream open reading frame) in-frame with the Gimap3 mRNA that impairs translation and imparts a negative effect on the steady-state protein abundance. We found that quantitative changes in the expression of Gimap3 and the paralogue Gimap5, which encodes a lysosomal protein, affect mtDNA segregation in the mouse hematopoietic tissues. We also show that Gimap3 localizes to the endoplasmic reticulum and not mitochondria as previously reported. Collectively these data show that the abundance of protein scaffolds on the endoplasmic reticulum and lysosomes are important to the segregation of the mitochondrial genome in the mouse hematopoietic compartment., (Copyright © 2015 by the Genetics Society of America.)

Mitochondrial DNA (mtDNA) is essential for aerobic energy production in eukaryotic cells, and mutations in this genome can lead to mitochondrial dysfunction. Human mtDNA mutations are typically heteroplasmic, a mix of mutant and wild-type genomes, which can present as a heterogeneous group of disorders ranging in severity from mild to fatal, and commonly affecting highly aerobic tissues such as heart, skeletal muscle, and neurons. During the 1990s, many research groups started to notice that mtDNA mutations could segregate depending upon the mutation and tissue. This segregation pattern can have a direct effect on the onset and severity of these mutations. However, these segregation patterns could not be easily explained by respiratory chain function, implying that there is regulation of mtDNA independent of its bioenergetic role. A lot of research on this topic has been largely descriptive, but over the last several years advances in mitochondrial biology have provided some mechanistic insight into the regulation of the organelle and its genome. This review addresses these advances with respect to somatic segregation of mtDNA in mammals.

Mitochondrial DNA (mtDNA) is a multi-copy genome encoding for proteins essential for aerobic energy metabolism. Mutations in mtDNA can lead to a variety of human diseases, from mild metabolic syndromes to severe fatal encephalomyopathies. Most mtDNA mutations co-exist with wild type genomes in a state known as heteroplasmy. The segregation of these pathogenic mutants is tissue and mutation specific, and a key determinant in the onset and severity of human mitochondrial disorders. We used a forward genetic approach in mice to identify and demonstrate that Gimap3 (GTP ase of immunity associated protein) is a key regulator of mtDNA segregation in leukocytes. The Gimap gene cluster is found only in vertebrates and appear to be a class of nucleotide-dependent dimerization GTP ases. Gimap3 is a membrane-anchored GTP ase with a critical role in T cell development. Here, we summarize our genetic findings and postulate how Gimap3 might regulate mtDNA genetics.

Mitochondrial DNA (mtDNA) sequence variants segregate in mutation and tissue-specific manners, but the mechanisms remain unknown. The segregation pattern of pathogenic mtDNA mutations is a major determinant of the onset and severity of disease. Using a heteroplasmic mouse model, we demonstrate that Gimap3, an outer mitochondrial membrane GTPase, is a critical regulator of this process in leukocytes. Gimap3 is important for T cell development and survival, suggesting that leukocyte survival may be a key factor in the genetic regulation of mtDNA sequence variants and in modulating human mitochondrial diseases., Competing Interests: The authors have declared that no competing interests exist.

Deramciclane, a camphor derivative, is a novel anxiolytic agent with a unique mechanism of action. It acts as a potent and specific antagonist at serotonin 5-HT2A/2C receptors, and exhibits anxiolytic efficacy in animal models. The aim of this double-blind, placebo-controlled, parallel-group study was to evaluate the efficacy, safety, and tolerability of a range of doses of deramciclane in patients with generalized anxiety disorder (GAD). Adult patients with a diagnosis of GAD (DSM-IV) and a Hamilton Anxiety Rating Scale (HAM-A) total score >or=18; a score >or=2 for the HAM-A items 'Anxious Mood' and 'Tension'; a score >or=4 on the Clinical Global Impression of Severity of Illness (CGI-S) Scale; and a score

To evaluate long-term efficacy and tolerability of the serotonin 5-HT1A receptor agonist, gepirone extended release (ER), a multicenter, randomized, placebo-controlled relapse prevention study was performed in patients with recurrent major depression (DSM-IV criteria). Patients 18 to 70 years, with a primary diagnosis of recurrent major depression (DSM-IV; 296.3) and a screening and baseline HAMD-17 total score >/=20 were eligible. After a 3- to 14-day (dependent on pretrial medication) single-blind placebo washout period, eligible patients entered an 8- or 12-week (depending on time to remission) open-label gepirone ER treatment period. They initially received a dose of 20 mg/d gepirone ER and were titrated to a dose of 40 to 80 mg/d. Patients who achieved remission (HAMD-17 total score /=16 or discontinuation for lack of efficacy. A total of 420 patients were treated in the open-label phase. Of these, 303 (72.1%) completed the open-label phase and 250 (59.5%) fulfilled the criteria for remission and were randomized into the double-blind continuation phase (gepirone ER: n = 126; placebo: n = 124). The mean (+/-SD) final titrated dose of gepirone ER was 61.9 (+/-17.0) mg/d in the double-blind continuation phase. The relapse rate in the gepirone ER group was statistically significantly lower than that in the placebo group, 23.0% versus 34.7%, respectively (P = 0.024). During the open-label phase, adverse events that occurred in more than 5% of patients were nausea (15.7%), dizziness (13.1%), headache (12.9%), insomnia (6.2%), and vertigo (6.0%). During the continuation phase, the incidence of newly or re-emerging adverse events was similar with gepirone ER (43.7%) and placebo (42.7%). Adverse events different from those occurring during the open-label phase were not apparent. All adverse events occurred in less than 5% of patients with the exception of flu syndrome and headache. In conclusion, gepirone ER at a dose range of 40 to 80 mg/d is effective for relapse prevention in patients with recurrent major depression. It is well tolerated during long-term treatment for up to approximately one year.

An integrative stepwise rehabilitation model for schizophrenics, especially those hospitalized for long periods, is described. The basic entities of this model are rehabilitation homes. The client moves from one step to the next according to their particular needs. The steps for living are: small homes, supported lodgings, rented quarters and own apartments. The steps of activities are: day care homes and day clubs, therapeutic sheltered workshop, test working, vocational training and labour market. The central rehabilitative aspects are the therapeutic community, living learning experiences, supporting of selfesteem and integrating with the social network. The psychiatric care system on the other hand and an important work of volunteers and friend services on the other support the rehabilitation. This work has shown during 14 years that the majority of clients can be rehabilitated to live as fairly independent and responsible persons.