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Obesity is considered as a major public health concern with strong economic and social burdens. Exposure to pollutants such as heavy metals can contribute to the development of obesity and its associated metabolic disorders, including type 2 diabetes and cardiovascular diseases. Adipose tissue is an endocrine and paracrine organ that plays a key role in the development of these diseases and is one of the main target of heavy metal accumulation. In this study, we determined by inductively coupled plasma mass spectrometry cadmium concentrations in human subcutaneous and visceral adipose tissues, ranging between 2.5 nM and 2.5 µM. We found a positive correlation between cadmium levels and age, sex and smoking status and a negative correlation between cadmium and body mass index. Based on cadmium adipose tissue concentrations found in humans, we investigated the effects of cadmium exposure, at concentrations between 1 nM and 10 µM, on adipose-derived human mesenchymal stem cells differentiated into mature adipocytes in vitro. Transcriptomic analysis highlighted that such exposure altered the expression of genes involved in trace element homeostasis and heavy metal detoxification, such as Solute Carrier Family transporters and metallothioneins. This effect correlated with zinc level alteration in cells and cellular media. Interestingly, dysregulation of zinc homeostasis and transporters has been particularly associated with the development of obesity and type 2 diabetes. Moreover, we found that cadmium exposure induces the pro-inflammatory state of the adipocytes by enhancing the expression of genes such as IL-6, IL-1B and CCL2, cytokines also induced in obesity. Finally, cadmium modulates various adipocyte functions such as the insulin response signaling pathway and lipid homeostasis. Collectively, our data identified some of the cellular mechanisms by which cadmium alters adipocyte functions, thus highlighting new facets of its potential contribution to the progression of metabolic disorders.

Polymorphisms in the region of the calmodulin-dependent kinase isoform D (CaMK1D) gene are associated with increased incidence of diabetes, with the most common polymorphism resulting in increased recognition by transcription factors and increased protein expression. While reducing CaMK1D expression has a potentially beneficial effect on glucose processing in human hepatocytes, there are no known selective inhibitors of CaMK1 kinases that can be used to validate or translate these findings. Here we describe the development of a series of potent, selective, and drug-like CaMK1 inhibitors that are able to provide significant free target cover in mouse models and are therefore useful as in vivo tool compounds. Our results show that a lead compound from this series improves insulin sensitivity and glucose control in the diet-induced obesity mouse model after both acute and chronic administration, providing the first in vivo validation of CaMK1D as a target for diabetes therapeutics.

International audience; BACKGROUND: An efavirenz-based regimen (with a 600-mg dose of efavirenz, known as EFV600) was the World Health Organization preferred first-line treatment for human immunodeficiency virus type 1 (HIV-1) infection until June 2018. Given concerns about side effects, dolutegravir-based and low-dose efavirenz-based combinations have been considered as first-line treatments for HIV-1 in resource-limited settings.METHODS: We conducted an open-label, multicenter, randomized, phase 3 noninferiority trial in Cameroon. Adults with HIV-1 infection who had not received antiretroviral therapy and had an HIV-1 RNA level (viral load) of at least 1000 copies per milliliter were randomly assigned to receive either dolutegravir or the reference treatment of low-dose efavirenz (a 400-mg dose, known as EFV400), combined with tenofovir and lamivudine. The primary end point was the proportion of participants with a viral load of less than 50 copies per milliliter at week 48, on the basis of the Food and Drug Administration snapshot algorithm. The difference between treatment groups was calculated, and noninferiority was tested with a margin of 10 percentage points.RESULTS: A total of 613 participants received at least one dose of the assigned regimen. At week 48, a viral load of less than 50 copies per milliliter was observed in 231 of 310 participants (74.5%) in the dolutegravir group and in 209 of 303 participants (69.0%) in the EFV400 group, with a difference of 5.5 percentage points (95% confidence interval [CI], -1.6 to 12.7; P1000 copies per milliliter) was observed in 3 participants in the dolutegravir group (with none acquiring drug-resistance mutations) and in 16 participants in the EFV400 group. More weight gain was observed in the dolutegravir group than in the EFV400 group (median weight gain, 5.0 kg vs. 3.0 kg; incidence of obesity, 12.3% vs. 5.4%).CONCLUSIONS: In HIV-1-infected adults in Cameroon, a dolutegravir-based regimen was noninferior to an EFV400-based reference regimen with regard to viral suppression at week 48. Among participants who had a viral load of at least 100,000 copies per milliliter when antiretroviral therapy was initiated, fewer participants than expected had viral suppression. (Funded by Unitaid and the French National Agency for AIDS Research; NAMSAL ANRS 12313 ClinicalTrials.gov number, NCT02777229.).

IntroductionClozapine, while effective in treatment refractory schizophrenia, is associated with significant weight gain, heart disease and increased risk of type 2 diabetes mellitus (T2DM). Although there is evidence for weight loss with metformin for people with obesity who are already taking clozapine, there have been no published trials that have investigated the effect of metformin in attenuating weight gain at the time of clozapine initiation.Methods and analysisA 24-week double-blind placebo-controlled trial of concomitant prescription of metformin at clozapine commencement. Eighty-six people being commenced on clozapine will be randomised to placebo or metformin (variable dose, up to 2 g/day). The primary outcome is comparative end point body weight, between the placebo and metformin groups. Secondary outcomes are comparative rates of conversion to T2DM, alteration of metabolic syndrome parameters, proportion gaining >5% body weight and changes in diet and appetite. We will additionally examine biomarkers associated with change in weight among trial participants.Ethics and disseminationEthics approval was granted by the Metro South Human Research Ethics Committee HREC/17/QPAH/538-SSA/17/QPAH/565. We plan to submit a manuscript of the results to a peer-reviewed journal, and present results at conferences, consumer forums and hospital grand rounds.Trial registration numberACTRN12617001547336; Pre-results.

Background: Persistent organic pollutants (POPs) have metabolic disrupting abilities and are suggested to contribute to the obesity epidemic. We investigated whether serum concentrations of POPs at 8-10 years of age were associated with subsequent development of overweight at age 14-16 and 20-22 years. Methods: The study was based on data from the European Youth Heart Study, Danish component (1997). Concentrations of several polychlorinated biphenyls (PCBs) and the organochlorine pesticides p,p-dichlorodiphenyldichloroethylene (DDE) and hexachlorobenzene (HCB) were measured in serum from children aged 8-10 years (n = 509). Information on BMI z-scores, waist circumference and % body fat were collected at clinical examinations at ages 8-10, 14-16 and 20-22 years. Multiple linear regression analyses were performed taking potential confounders into account. Results: Overall, POP serum concentrations were low: median ΣPCB 0.18 µg/g lipid, DDE 0.04 µg/g lipid and HCB 0.03 µg/g lipid. POPs were generally not associated with weight gain at 14-16 and 20-22 years of age, except for an inverse association among the highest exposed girls at 20-22 years of age, which might possibly be explained by multiple testing or residual confounding. Conclusion: This study suggests that, in a low exposed population, childhood serum concentrations of PCB, DDE, and HCB are not associated with subsequent weight gain.

Background Long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA) of marine origin exert multiple beneficial effects on health. Our previous study in mice showed that reduction of adiposity by LC n-3 PUFA was associated with both, a shift in adipose tissue metabolism and a decrease in tissue cellularity. The aim of this study was to further characterize the effects of LC n-3 PUFA on fat cell proliferation and differentiation in obese mice. Methods A model of inducible and reversible lipoatrophy (aP2-Cre-ERT2 PPARγL2/L2 mice) was used, in which the death of mature adipocytes could be achieved by a selective ablation of peroxisome proliferator-activated receptor γ in response to i.p. injection of tamoxifen. Before the injection, obesity was induced in male mice by 8-week-feeding a corn oil-based high-fat diet (cHF) and, subsequently, mice were randomly assigned (day 0) to one of the following groups: (i) mice injected by corn-oil-vehicle only, i.e."control" mice, and fed cHF; (ii) mice injected by tamoxifen in corn oil, i.e. "mutant" mice, fed cHF; (iii) control mice fed cHF diet with15% of dietary lipids replaced by LC n-3 PUFA concentrate (cHF+F); and (iv) mutant mice fed cHF+F. Blood and tissue samples were collected at days 14 and 42. Results Mutant mice achieved a maximum weight loss within 10 days post-injection, followed by a compensatory body weight gain, which was significantly faster in the cHF as compared with the cHF+F mutant mice. Also in control mice, body weight gain was depressed in response to dietary LC n-3 PUFA. At day 42, body weights in all groups stabilized, with no significant differences in adipocyte size between the groups, although body weight and adiposity was lower in the cHF+F as compared with the cHF mice, with a stronger effect in the mutant than in control mice. Gene expression analysis documented depression of adipocyte maturation during the reconstitution of adipose tissue in the cHF+F mutant mice. Conclusion Dietary LC n-3 PUFA could reduce both hypertrophy and hyperplasia of fat cells in vivo. Results are in agreement with the involvement of fat cell turnover in control of adiposity.

Background: The modulation of energetic homeostasis by pollutants has recently emerged as a potential contributor to the onset of metabolic disorders. Diethylhexyl phthalate (DEHP) is a widely used industrial plasticizer to which humans are widely exposed. Phthalates can activate the three peroxisome proliferatoractivated receptor (PPAR) isotypes on cellular models and induce peroxisome proliferation in rodents.Objectives: In this study, we aimed to evaluate the systemic and metabolic consequences of DEHP exposure that have remained so far unexplored and to characterize the underlying molecular mechanisms of action.Methods: As a proof of concept and mechanism, genetically engineered mouse models of PPARs were exposed to high doses of DEHP, followed by metabolic and molecular analyses.Results: DEHP-treated mice were protected from diet-induced obesity via PPARalpha-dependent activation of hepatic fatty acid catabolism, whereas the activity of neither PPARbeta nor PPARgamma was affected. However, the lean phenotype observed in response to DEHP in wild-type mice was surprisingly abolished in PPARalpha-humanized mice. These species differences are associated with a different pattern of coregulator recruitment.Conclusion: These results demonstrate that DEHP exerts species-specific metabolic actions that rely to a large extent on PPARalpha signaling and highlight the metabolic importance of the species-specific activation of PPARalpha by xenobiotic compounds. Editor's SummaryDiethylhexyl phthalate (DEHP) is an industrial plasticizer used in cosmetics, medical devices, food packaging, and other applications. Evidence that DEHP metabolites can activate peroxisome proliferatoractivated receptors (PPARs) involved in fatty acid oxidation (PPARalpha and PPARbeta) and adiposite function and insulin resistance (PPARgamma) has raised concerns about potential effects of DEHP on metabolic homeostasis. In rodents, PPARalpha activation also induces hepatic peroxisome proliferation, but this response to PPARalpha activation is not observed in humans. Feige et al. (p. 234) evaluated systemic and metabolic consequences of high-dose oral DEHP in combination with a high-fat diet in wild-type mice and genetically engineered mouse PPAR models. The authors report that mice exposed to DEHP gained less weight than controls, without modifying their feeding behavior; they also exhibited lower triglyceride levels, smaller adipocytes, and improved glucose tolerance compared with controls. These effects, which were observed in mice fed both high-fat and standard diets, appeared to be mediated by PPARalpha-dependent activation of hepatic fatty acid catabolism without apparent involvement of PPARbeta or PPARgamma. However, mouse models that expressed human (versus mouse) PPARalpha tended to gain more weight on a high-fat diet than their DHEP-unexposed counterparts. The authors conclude that findings support species-specific metabolic effects of DEHP mediated by PPARalpha activation.

Most patients with type 2 diabetes are overweight or obese, overweight or obesity increases the risk of developing type 2 diabetes and obesity per se is strongly associated with multiple cardiometabolic risk factors. However, many antidiabetic treatments increase body weight. The oral antidiabetic agent, metformin, has been evaluated in hundreds of clinical studies in diverse patient populations during approximately five decades of clinical use. This review summarizes the effects of metformin on body weight, with special reference to studies of longer duration (>/=6 months) as both diabetes and obesity are long-term conditions. Approximately half of studies in drug-naive type 2 diabetic patients demonstrated significant weight loss with metformin compared with baseline or comparator drugs, although pooled analyses have suggested no significant effect versus placebo. Similarly, metformin has been shown to induce weight loss in obese nondiabetic populations, although studies of long duration in this population are scarce. Metformin does appear to mitigate the adverse effects of insulin on body weight. The weight-neutral or weight-sparing effects of metformin constitute a therapeutic advantage in diabetes management where other first-line oral antidiabetic treatments often promote clinically significant weight gain.

Background: Metabolic side effects induced by psychotropic drugs represent a major health issue in psychiatry. CREB-regulated transcription coactivator 1 (CRTC1) gene plays a major role in the regulation of energy homeostasis and epigenetic mechanisms may explain its association with obesity features previously described in psychiatric patients. This prospective study included 78 patients receiving psychotropic drugs that induce metabolic disturbances, with weight and other metabolic parameters monitored regularly. Methylation levels in 76 CRTC1 probes were assessed before and after 1 month of psychotropic treatment in blood samples. Results: Significant methylation changes were observed in three CRTC1 CpG sites (i.e., cg07015183, cg12034943, and cg 17006757) in patients with early and important weight gain (i.e., equal or higher than 5% after 1 month; FDR p value = 0.02). Multivariable models showed that methylation decrease in cg12034943 was more important in patients with early weight gain (>= 5%) than in those who did not gain weight (p = 0.01). Further analyses combining genetic and methylation data showed that cg12034943 was significantly associated with early weight gain in patients carrying the G allele of rs4808844A>G (p = 0.03), a SNP associated with this methylation site (p = 0.03). Conclusions: These findings give new insights on psychotropic-induced weight gain and underline the need of future larger prospective epigenetic studies to better understand the complex pathways involved in psychotropic-induced metabolic side effects.