Frontiers in Endocrinology

This study investigates the individual and combined effects of Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), and metformin on glucose regulation in a non-obese, insulin-deficient model of type 2 diabetes. Female Goto-Kakizaki (GK) rats underwent RYGB, SG, or sham surgery. Three weeks postoperatively, animals received metformin (50 mg/kg/day, 5 days/week) or vehicle for three additional weeks. Glucose tolerance was assessed using a standardized meal test, and insulin sensitivity was evaluated by insulin tolerance test. Plasma levels of GLP-1, GIP, insulin, and leptin were measured. RYGB and SG reduced body weight, food intake, and leptin levels, and improved fasting glucose, glucose tolerance, insulin sensitivity, and postprandial incretin and insulin secretion. Metformin alone improved glucose tolerance and insulin sensitivity independently of incretin or insulin changes. When combined with surgery, metformin further reduced postprandial glycemic excursions and advanced the glycemic peak but did not enhance insulin sensitivity or hormone secretion beyond surgery alone. In conclusion, bariatric surgery and metformin independently improve glucose regulation in non-obese diabetic GK rats. Their combination provides additional benefits on postprandial glucose control, despite no additive effects on insulin sensitivity or hormone levels. These findings support the use of metformin as an adjunct to bariatric surgery in insulin-deficient diabetes and highlight the need for longer-term, sex-inclusive studies to enhance translational relevance. NEW & NOTEWORTHYBariatric surgery and metformin each improved glucose regulation in non-obese, insulin-deficient female GK rats. Their combination yielded an additional reduction in postprandial glycemic excursions without further enhancing insulin sensitivity or incretin/insulin secretion. These findings reveal that postprandial glucose dynamics can be modulated independently of hormonal or insulin-sensitivity pathways, highlighting distinct and dissociable mechanisms governing glucose homeostasis in an insulin-deficient model.

Aims: Sarcopenia and sarcopenic obesity are associated with increased risks of cardiovascular (CV) disease and mortality. This study examined the associations of body composition and daily physical activity with mortality, CV events and cancer in patients with diabetes. Methods: This prospective cohort study included patients with diabetes treated at a specialised clinic in Japan between January 2018 and March 2023. Body composition, including visceral adipose tissue (VAT), was assessed by bioelectrical impedance analysis. Daily physical activity was evaluated using the non-exercise activity thermogenesis (NEAT) questionnaire, and handgrip strength (HGS) was measured by dynamometry. Cox proportional hazards models were used to assess associations with mortality, CV events, and cancer. Results: Among 2,024 patients (mean age 63.0 years, BMI 24.6 kg/m^2, HbA1c 7.8%), NEAT, HGS, and VAT were not independently associated with all-cause mortality. Higher VAT was associated with increased cancer risk (HR 1.485; 95% CI 1.101-2.003; p = 0.009). Higher HGS was inversely associated with CV event risk (HR 0.951; 95% CI 0.919-0.984; p = 0.004). NEAT was not associated with any outcome. Conclusions: Higher VAT was associated with increased cancer risk, whereas higher HGS was protective against CV events. Incorporating body composition and HGS assessments into clinical practice may improve risk stratification and management in patients with diabetes.

OBJETIVEFood intake, energy expenditure, and metabolic homeostasis depend on hypothalamic neurons responses to peripheral signals, such as leptin, involving the primary cilium (PC). The PC is crucial for signal transduction and is dynamically regulated by assembly/disassembly or reabsorption of its microtubules-based axoneme. Absence or reduction in the length of PC is associated with obesity and type-2 diabetes (T2D). In other cellular systems, PC reabsorption is primarily regulated by calcium-mediated activation of the Aurora kinase A (AurkA)/histone deacetylase C6 (HDAC6) axis, which promotes axonemal disassembly. Here, we explore the role of Galectin-8 (Gal-8), a glycan-binding protein, in regulating PC structure and signaling related to metabolic parameters in hypothalamic neurons. METHODSGal-8 effects were assessed in hypothalamic Clu-177 cells by analyzing the PC presence and length by immunofluorescence, PC dynamics, and intracellular calcium changes by in vivo cell imaging, activation of FAK, Src, AurkA, HDAC6 and STAT3 by immunoblot, and Gal-8 interactions with {beta}1-integrins by pull-down assays. Gal-8-KO mice were used to evaluate PC length in hypothalamic neurons, metabolic phenotype, and responses to Gal-8 intranasal administration. RESULTSIn Clu-177 cells, Gal-8 induced PC reabsorption and reduced responsiveness to leptin signaling towards STAT3 activation. PC reabsorption involves glycan-mediated Gal-8 interactions with a5b1 and a3b1 integrins, activation of FAK and Src leading to calcium influx through L-type calcium channels (LTCC), and subsequent AurkA/HDAC6 axis activation. Gal-8-KO mice showed longer PC in hypothalamic neurons, higher STAT3 activation, decreased body weight and food intake, improved glucose tolerance, higher locomotor activity, and a glycolytic respiratory exchange rate (RER). Daily intranasal Gal-8 administration for 4 days restored hypothalamic PC length and STAT3 signaling, as well as RER in Gal-8-KO mice to the level of WT mice. CONCLUSIONSEndogenous Gal-8 is required to maintain PC structure and leptin signaling in hypothalamic neurons, impacting body weight, energy balance, and glucose homeostasis. The mechanism involves calcium influx via LTCC downstream of b1-integrin/FAK/Src signaling and subsequent AurkA/HDAC6 axis activation. Both Gal-8 and the AurkA/HDAC6 axis may offer new therapeutic opportunities for treating metabolic diseases characterized by ciliogenesis impairment, including obesity and type-2 diabetes.

Objective: Patients and physicians frequently focus on HbA1c and weight alone. We hypothesized that individuals with similar HbA1c and BMI may present markedly distinct metabolic backgrounds. We investigated whether the adipo-B index- composite of adipose insulin resistance (adipo-IR) and beta-cell function (HOMA-B)-can uncover hidden heterogeneity in this clinically homogeneous population. Methods: A total of 399 newly diagnosed, drug-naive Japanese subjects with T2DM were analyzed. Histograms of HbA1c and BMI demonstrated peak distributions within HbA1c 8-10% and BMI 24-26. Based on these distributions, a clinically homogeneous subgroup was defined to minimize confounding by glycemic severity and adiposity. Metabolic parameters including FBG, insulin, FFA, HOMA-R, HOMA-B, adipo-IR, adipo-B, T-C, TG, HDL-C and non-HDL-C were analyzed. Simple regression, multivariable linear regression, and subgroup stratification analyses were performed. Results: Despite comparable HbA1c and BMI by design, adipo-B stratification revealed significant differences in HOMA-B, FFA, non-HDL-C, and TG, whereas HOMA-R stratification identified only higher insulin and adipo-IR without differences in lipids or HOMA-B. Thus, adipo-B-but not HOMA-R-identified a lipotoxic, beta-cell-stressed phenotype invisible to conventional markers. Simple regression showed significant positive correlations between adipo-B and HbA1c, FBG, FFA, T-C, TG, and non-HDL-C, and negative correlations with insulin and HOMA-B. Multivariable linear regression confirmed that adipo-B was independently associated with non-HDL cholesterol, TG, and FFA after adjustment for HbA1c and BMI. Conclusion: Even among patients with identical HbA1c and BMI, the adipo-B index uncovers clinically relevant metabolic heterogeneity, supporting its role as a functional marker of the adipose-pancreas axis and a potential tool for precision phenotyping in early T2DM.

BackgroundHeterozygous c.283+1G>A and c.283G>A variants in the THRB gene, encoding for thyroid hormone receptor (TR){beta}1 and {beta}2, lead to autosomal dominant macular dystrophy (ADMD). We report the detailed clinical characterization of two first-degree relatives with ADMD, heterozygous for THRB c.283+1G>A, and an unrelated ADMD patient with a novel variant, c.283G>C. The genomic and molecular consequences of both variants were studied. MethodsgDNA and mRNA were obtained from leukocytes. Clinical characterization included biochemistry, bone density and body composition, ECG, echocardiography, ultrasound, audiometry and color-vision. In vitro assays investigated TR function and DNA binding. ResultsThe patients manifested no resistance to thyroid hormone beta (RTH{beta}) and had normal FT4 and TSH. Detailed studies in two patients showed no goiter, tachycardia, hypercholesterinemia or hepatic steatosis. Hearing was not impaired. Both had impaired color vision and reduced bone density. RT-PCR from all three patients revealed skipping of exon 4 exclusive to TR{beta}1, producing a deletion of 87 amino acids in the N-terminal domain (TR{beta}1{Delta}NTD). In vitro, DNA-binding affinity of TR{beta}1{Delta}NTD to DR4-TRE with or without RXR was comparable to TR{beta}1WT. Surprisingly, TR{beta}1{Delta}NTD was transcriptionally twice more active than TR{beta}1WT with a similar EC50 for T3, demonstrating gain-of-function of TR{beta}1{Delta}NTD. THRA expression in leukocytes was increased by 3-fold compared to unrelated controls and different from RTH{beta} patients. ConclusionThese THRB splice site variants produce TR{beta}1 exon 4 skipping, resulting in a gain-of-function mutant, TR{beta}1{Delta}NTD. This explains the dominant ADMD phenotype devoid of RTH{beta} and suggests a TR{beta}1 gain-of-function syndrome.

Abstract Context Lipoprotein(a) [Lp(a)] is a genetically determined and independent cardiovascular risk factor, traditionally considered stable across the lifespan, supporting a single lifetime measurement strategy. However, its longitudinal behavior during childhood and adolescence remains poorly characterized, particularly in individuals with type 1 diabetes who are at increased lifetime risk of cardiovascular disease. Objective We aimed to characterize intra- and inter-individual trajectories of Lp(a) in youth with type 1 diabetes and to assess the implications of variability for cardiovascular risk classification. Methods We conducted a retrospective single-center cohort study of children and adolescents with type 1 diabetes followed at Geneva University Hospitals between 2012 and 2023. Annual fasting Lp(a) concentrations were analyzed longitudinally. Variability was assessed in participants with more than two measurements. Clinically relevant thresholds were used to evaluate risk reclassification. Statistical analyses included paired Wilcoxon tests, Pearson and Kendall correlations, and Holm-adjusted p-values. Results A total of 287 participants contributed 1,408 Lp(a) measurements over a median follow-up of 6.2 years (IQR 2.9-9.6). At baseline, 26% had elevated Lp(a) (above or equal 300 mg/L). Among participants with serial measurements, 32% exhibited intraindividual fluctuations exceeding 50% of their maximum value. Reclassification across the 300 mg/L threshold occurred in 11.9% of participants. Lp(a) concentrations peaked between ages 10 and 13 years and declined thereafter. Modest seasonal variation was observed, with higher levels in autumn and winter (P < 0.05). Conclusions In youth with type 1 diabetes, Lp(a) demonstrates clinically relevant intraindividual variability over time. These findings suggest that reliance on a single lifetime measurement may lead to misclassification of cardiovascular risk and support repeated assessment, particularly during adolescence, to improve risk stratification.

Administration of ciliary neurotrophic factor (CNTF) reduces food intake and body weight in both humans and experimental animals, where it also ameliorates hyperglycemia, hyperinsulinemia, and dyslipidemia. To exert its anti-obesogenic and anti-diabetogenic effects, CNTF targets brain feeding centers as well as multiple peripheral organs inducing the phosphorylation of the transcription factor signal transducer and activator of transcription 3 (p-STAT3). However, data showing which peripheral cytotypes are specifically targeted by exogenous CNTF in vivo in metabolically relevant organs are currently lacking. Here, we first evaluated the gene expression levels of the subunits of the tripartite CNTF receptor (Cntfr) complex, i.e., the Cntfr, the leukemia inhibitory factor receptor {beta} (Lifr{beta}) and the glycoprotein 130 (gp130), by quantitative real-time PCR in metabolically relevant organs of adult male mice: gastrointestinal (GI) tract, pancreas, liver, visceral and subcutaneous white (WAT) and interscapular brown adipose tissue (iBAT), skeletal muscle and the sciatic nerve. We then quantified p-STAT3 by Western blotting in these organs after intraperitoneal administration of CNTF (0.3 mg/kg) or saline. Finally, we mapped CNTF-responsive cells by immunohistochemistry, followed by morphometric quantification and confocal microscopy in both CNTF- and saline-treated mice. Lifr{beta} and gp130 were ubiquitously detected across all the investigated organs; the Cntfr showed the highest expression levels in the skeletal muscle, sciatic nerve, and iBAT, whereas it was found to be expressed to a lesser extent in the other sites. Administration of CNTF led to a significant increase of p-STAT3/STAT3 protein ratio in all organs examined, except the duodenum, and induced a distinctive pattern of cell nuclear p-STAT3 immunoreactivity. Notably, along the analyzed GI tract CNTF induced nuclear STAT3 phosphorylation in neurons of the submucosal and myenteric plexuses of the enteric nervous system and in contractile cells of the muscularis externa, where the response peaked in the mesenteric gut and colon. In the pancreas, CNTF triggered a higher activation within the endocrine component compared to the exocrine parenchyma. In the liver, CNTF induced STAT3 phosphorylation not only in parenchymal cells but also in sinusoids and resident macrophages. The cytokine activated p-STAT3 in subcutaneous and visceral white adipocytes, but also in brown adipocytes, with a prominent response observed in the beige subcutaneous adipocytes; adipose resident macrophages and endothelial cells of numerous blood vessels were also CNTF-responsive. Lastly, in skeletal muscle, a major site for glucose/lipid utilization, CNTF induced widespread nuclear p-STAT3 immunoreactivity in muscle fibers and in connective and Schwann cells of the peripheral nerves, including the sciatic nerve, supplying the gastrocnemius. In conclusion, our data indicate that CNTF acts across diverse cytotypes within metabolically relevant organs and tissues, likely fostering its peripheral metabolic effects through this cellular heterogeneity.

Oxytocin is a hypothalamic hormone and neuromodulator that has been linked to a variety of different functions, including parturition, social behavior, and cognitive processing. More recently, oxytocin has also been associated with metabolism and energy balance. However, evidence to date in this field has been inconsistent, especially in human research. To address this, we performed a preregistered systematic review and meta-analysis, which synthesized existing literature on the effect of exogenous oxytocin administration compared to a placebo on caloric intake and appetite in humans, using a living meta-analysis approach. Results indicated a significant, reductive effect of oxytocin administration on appetite in participants belonging to certain patient groups (e.g., obesity or type II diabetes; Hedges' g = -0.21). A separate moderator analysis evaluating oxytocin's effect on caloric intake revealed a conditional effect depending on the patient group, with the obesity group showing a significant effect. We did not find any statistically significant effects in healthy participants. However, further analyses revealed that these effects were also not equivalent, indicating that the data are currently too insensitive to draw clear conclusions. Taken together, the results provide some evidence for the role of oxytocin in regulating appetite in an anorexigenic, possibly homeostatic fashion. Future updates in this living meta-analysis may lead to more definitive conclusions.

BackgroundPET-CT scans of radioactive exendin-4, a ligand of the GLP-1 receptor, are claimed to provide a biomarker of pancreatic beta cell mass (BCM), although the GLP-1 receptor is expressed also in the exocrine pancreas (PX). Parotid glands may be a reference tissue for GLP-1 receptor expression in exocrine cells of the GI system. Our aims were 1. To assess biomarker(s) of BCM derived from 68Ga-NODAGA-exendin-4 PET-CT scans in participants with long-standing type 1 diabetes (T1DM) or in subjects with obesity (OBESE); 2. To investigate the relationship between biomarker(s) of BCM and a biomarker of beta cell functional mass (BCFxM) in OBESE. MethodsT1DM (n=8, Age: 50.4{+/-}3.8 yrs; T1DM duration: 34.2{+/-}3.0 yrs; BMI: 26.6{+/-}1.1 kg/m2; HbA1c: 7.5{+/-}0.36%) and OBESE (n=9; Age:48.2{+/-}2.2 yrs; BMI: 37.4{+/-}1.1 kg/m2; HbA1c: 5.4{+/-}0.17%) underwent two studies: 1) 68Ga-NODAGA-exendin-4 PET-CT scan of both PX and parotid glands 45-60 after i.v. injection and with CT-assessment of PX volume to compute biomarkers of BCM based on SUV (BCMSUV) or clearance (CLEAR; BCMCLEAR); 2) Mixed meal test (MMT), with measurement of plasma glucose, C-peptide, GLP-1 and GIP curves to assess BCFxM with state-of-art mathematical modeling. ResultsThe C-peptide response to the MMT in T1DM participants was absent or negligible, whereas the OBESE displayed a robust BCFxM. The PX volume was smaller in T1DM than in OBESE (51.7{+/-}6.6 vs 92.9{+/-}10.9 cc; p=0.007). The biomarkers of BCM, as assessed by 68Ga-NODAGA-exendin-4 SUV or CLEAR, were 6.6-fold (p=0.003) and 5.0-fold (p=0.002) lower, respectively, in T1DM than in OBESE. BCFxM was correlated in OBESE to both biomarkers of BCM (r=0.91 p<0.001, and r=0.82 p=0.006, respectively). Conclusion/interpretation68Ga-NODAGA-exendin-4 derived biomarkers of BCM can discriminate T1DM from OBESE. In OBESE 68Ga-NODAGA-exendin-4 derived BCM appears to be a pivotal determinant of the beta cell response to MMT and may be valuable to compare and monitor BCM both in research and in clinical settings. Research in contextO_ST_ABSWhat is already known about this subject?C_ST_ABSO_LIChanges in pancreatic beta cell functional mass are at the heart of alterations in glucose regulation, including diabetes mellitus. Beta cell functional mass can be assessed by mathematical modeling of the in vivo beta cell response to intravenous or oral challenges. C_LIO_LIBeta cell functional mass is the product of beta cell mass times beta cell function per mass unit, i.e. the result of two distinct entities, mass and function. No in vivo methods can dissect out beta cell mass and function. C_LIO_LIPancreatic 68Ga-exendin-4 uptake, as measured by PET-CT, has been proposed as a non-invasive biomarker of beta cell mass. However, the ratio of 3.6:1 between endocrine and exocrine pancreas 68Ga-exendin 4 uptake suggests that there is room for improvement. C_LI What are the key questions?O_LIDoes an improved 68Ga-exendin4 method provide a better separation between participants with type 1 diabetes and expected zero/nil beta cell mass vs people with nondiabetic obesity? C_LIO_LIWhat is the role of beta cell mass in determining beta cell functional mass in people living with obesity? C_LI What are the new findings?O_LIThe improvement in the quantitation of beta cell 68Ga-exendin-4 binding to beta cells resulted in a clearcut separation of participants with type 1 diabetes and expected zero/nil beta cell mass from people living with obesity C_LIO_LIIn people living with obesity, beta cell mass, as assessed by 68Ga-exendin-4 PET-CT scan, is a pivotal determinant of beta cell functional mass, as assessed by mathematical modeling of a frequently sampled mixed meal test C_LI How might this impact on clinical practice in the foreseeable future?O_LIThis method has the potential to track changes in beta cell mass both between-subjects and within-subjects over time C_LIO_LINatural history of glucose (in)tolerance and the impact of disease modifier candidates in diabetes mellitus can be assessed with the present method C_LI

BackgroundVertical sleeve gastrectomy (VSG) improves glycaemic control in type 2 diabetes (T2D) through mechanisms that extend beyond weight loss. The interaction between glucocorticoid metabolism and inflammation in this context remains unclear. MethodsWe investigated the role of 11{beta}-hydroxysteroid dehydrogenase type 1 (11{beta}HSD1) in mediating the metabolic effects of VSG in humans and mice. Subcutaneous adipose tissue biopsies were collected before and 6 months after VSG. Parallel studies were conducted in lean and high-fat diet-fed mice undergoing VSG or sham surgery, alongside 11{beta}HSD1 knockout models. Glucose tolerance and expression of 11{beta}HSD1 and interleukin-6 (IL6) were assessed. Mechanistic interactions were examined in IL6-treated human hepatocytes. ResultsVSG reduced 11{beta}HSD1 and IL6 expression in human adipose tissue and improved insulin resistance. In lean mice, VSG improved glucose tolerance and downregulated both markers independently of weight loss. 11{beta}HSD1 knockout mice exhibited improved glucose tolerance despite increased adiposity, partially recapitulating the VSG phenotype. Both interventions reduced circulating and tissue IL6 levels. IL6 stimulation increased HSD11B1 expression in hepatocytes. Conclusions11{beta}HSD1 links glucocorticoid metabolism, inflammation, and glucose homeostasis following VSG. Targeting this pathway may offer a strategy to replicate key metabolic benefits of metabolic bariatric surgery.

Aims/Hypothesis: Behavioral and phenotypic characteristics do not fully explain variability in African Americans with youth-onset type 2 diabetes (Y-T2D) treated with metformin with or without liraglutide. We hypothesized that biological heterogeneity, including genetic variation in the metformin transporter OCT1, influences metformin pharmacokinetics and hepatic glucose flux. Therefore, we sought to characterize metformin pharmacokinetics in Y-T2D and evaluate genetic variants known to modulate metformin efficacy in adults to determine the mechanisms underlying variation in treatment response. Methods: We evaluated genetic variants related to metformin transport and mechanisms of action in 30 Y-T2D using a candidate-gene approach to evaluate the association of pharmacogenetic variants with fasting glucose and gluconeogenesis. In a subset of Y-T2D randomized to 3 months of metformin (n=11) or metformin and liraglutide (n=8), we constructed a metformin population pharmacokinetic model and evaluated gene variant associations. Results: A one-compartment first-order absorption and elimination pharmacokinetic model provided the optimal fit. Metformin pharmacokinetic parameters were similar by group and not related to glycemia. The rs628031_OCT1 A allele was associated with greater metformin clearance. The rs622342_OCT1 C allele was associated with lower post-treatment fractional gluconeogenesis ({beta} [95% CI] = -8.8 [-14.13, -3.47] %, Adjusted R2 = 0.56, P = 0.003). The rs7903146_TCF7L2 T allele was associated with greater reductions in fasting glucose among those treated with metformin + liraglutide ({beta} = -1.32 [-2.42, -0.22] mmol/L, Adjusted R2 = 0.8, P<0.002), but baseline glucose and gluconeogenesis (P<0.0001) were the strongest predictors of post-treatment glycemia. Conclusion/interpretation: In Y-T2D, OCT1 gene variants rs628031 and rs622342 were associated with metformin clearance and gluconeogenesis, respectively. TCF7L2 variant rs7903146 may contribute to differences in glycemic response in youth treated with metformin and liraglutide. These findings suggest genetic variants may be important for understanding variable metformin response in Y-T2D.

Plantar tissue adaptation during activity is thought to contribute to diabetic foot ulceration (DFU), yet most existing studies only measure compressive quasi-static properties. This pilot study developed an ultrasound-loadcell measurement tool, PlantarSense, and used an infrared thermometer to measure dynamic compressive and shear energy dissipation ratio (EDR) and temperature of plantar-tissue at the first metatarsal head (1stMTH) and calcaneus in people living with and without diabetes at baseline, post-walk, and post-recovery. People living with diabetes showed significantly greater post-walk temperature increases (11.0 % vs 6.9% in controls at calcaneus, p=0.03) and less complete thermal recovery than controls. Baseline compressive EDR at the 1stMTH was significantly higher in people living with diabetes (67.8% vs 56.0% in controls, p=0.04). EDR modulation was greater from shear loading (21.5%) than compression (5.4%) and post-walk induced reductions in EDR were present in all participants, but people living with diabetes showed a 20% lower recovery than controls. Impaired thermoregulation and tissue adaptation in people living with diabetes was demonstrated by plantar temperature and EDR differences in post-walk and post-recovery. Future work is needed to test more participants with a greater range of diabetes progression to quantify statistically significant plantar tissue differences to inform DFU risk management.

Osteocytes and adipocytes represent cells with disparate functions. Osteocytes regulate bone metabolism (remodeling) and bone homeostasis, while adipocytes regulate energy metabolism and energy storage. Here, we demonstrate that osteocyte phenotype consists of adipocytic features which are under control of peroxisome proliferator-activated receptor gamma (PPARG), a master regulator of adipocyte differentiation and function. Using a mouse model with osteocyte-specific deletion of PPARG (OT{gamma}KO) and osteocyte cellular model of MLO-Y4 cells edited with CRISPR/Cas9 for PPARG deficiency, we are demonstrating that under PPARG control osteocytes produce and secrete adiponectin (ADIPOQ), and they are equipped in adipocyte-specific mechanisms for lipid-storage and their metabolism. Under PPARG, osteocytes accumulate lipid droplets which correlate with their capability to cover up to 20% of energy requirements from fatty acids metabolism. Although osteocytes like osteoblasts mainly express perilipin 2 (Plin2), however similarly to adipocytes, lipid droplets accumulation is associated with expression of perilipin 1 (Plin1) under PPARG control. Similarly, lipids accumulation and metabolism involve adipocyte-specific activities including fatty acids binding protein 4 (Fabp4), hormone-specific lipase (Hsl) and adipocyte-specific triglyceride lipase (Atgl), which expression are under PPARG control. These studies provide a new understanding of osteocyte biology which include adipocyte-like endocrine and lipid metabolism features probably reflecting an adaptation to their unique localization and a need for a maintenance of functional fitness in these conditions. They deepen our comprehension of the crossroads of osteocyte and adipocyte function and underscore the therapeutic potential of targeting common molecular pathways in both cell types for managing metabolic disorders and skeletal diseases.

Background: Repeated metabolic-bariatric surgery (MBS, r-BS) represents 10-25% of all MBS procedures and is commonly performed for recurrent weight gain after initial weight loss. How weight loss followed by regain reshapes adipose tissue biology remains unclear. We hypothesized that women undergoing r-BS exhibit a distinct adipose tissue signature compared with those undergoing primary bariatric surgery (p-BS). Methods: We analyzed subcutaneous and visceral adipose tissues (SAT, VAT, respectively) from women undergoing either p-BS, or r-BS with documented >15% weight loss after prior MBS. Tissues were assessed histologically, molecularly, and functionally (activation of human microglia cells (HMC3) by SAT secretome). Results: Consistent with other cohorts, women undergoing r-BS (n=21) trended to be older (47.2 vs. 40.5 y, p=0.06) than those undergoing p-BS (n=35), with a lower BMI (42.3 vs. 45.6 kg/m2, respectively, p=0.103), and a trend for improved cardiometabolic risk parameters such as fasting insulin, CRP and HDL-c. Adipose tissue histological features (adipocyte size, fibrosis, macrophage and crown-like structure abundance) were similar, while adipose mast cells were slightly (though insignificantly) more prevalent in r-BS. A single-nucleus RNA-seq-based deconvolution algorithm applied to bulk RNA-seq confirmed the absence of a major shift in adipose tissue cell-type composition. Yet, it uncovered a unique SAT transcriptome, with activation of inflammatory pathways in r-BS. Consistently, SAT explants from r-BS secreted higher protein concentrations of NFkB-regulated cytokines IL6 and IL8. Biological impact of the more inflammatory secretome was demonstrated by its increased ability to activate human microglia cells. Conclusions: Prior BS with significant weight loss-regain in women is associated with an inflammatory SAT transcriptome and secretome, possibly reflecting altered adipose-brain endocrine communication.

BackgroundObesity is a chronic multifactorial disease characterized by substantial interindividual variability in weight loss after lifestyle intervention and bariatric surgery. Thyroid hormones play a key role in energy homeostasis, but their influence on postoperative weight outcomes remains insufficiently studied. ObjectiveTo evaluate the association between preoperative thyroid status and changes in body mass index (BMI) after lifestyle intervention and bariatric surgery over a five-year follow-up. MethodsWe conducted a retrospective cohort study including adults with class II or III obesity enrolled in the Obesite Severe et Epigenetique (OBESEPI) study. All participants underwent preoperative lifestyle intervention followed by bariatric surgery. Thyroid status was classified as euthyroid or hypothyroid based on clinical and biochemical criteria. BMI was assessed at baseline and at nine postoperative time points over five years. ResultsAmong 435 included patients, 71 (16.8%) had hypothyroidism. Baseline BMI was similar between groups, whereas diabetes was more frequent in hypothyroid patients (52.1% vs 37.7%; p = 0.022). Hypothyroid patients had significantly higher BMI at 6-24 months after surgery, but differences were no longer significant beyond three years. BMI trajectories and magnitude of weight regain were comparable between groups. Higher preoperative TSH levels were independently associated with BMI regain (OR 1.32, 95% CI 1.00-1.72; p = 0.047). Higher baseline BMI, younger age, and female sex were also associated with greater BMI regain. ConclusionsHypothyroidism was associated with lower early postoperative weight loss but did not influence long-term BMI trajectories. Higher preoperative TSH levels were independently associated with BMI regain. KEYPOINTSO_LIPreoperative hypothyroidism is associated with reduced early weight loss during the first two years after bariatric surgery. C_LIO_LILong-term BMI trajectories and weight regain patterns are similar between hypothyroid and euthyroid patients beyond three years of follow-up. C_LIO_LIHigher preoperative TSH levels independently predict BMI regain. C_LIO_LIBaseline BMI, younger age, and female sex remain key determinants of the magnitude of BMI regain after bariatric surgery. C_LI

Obesity affects millions of people worldwide and has serious complications such as cardiovascular disease and diabetes. Current treatments for obesity target proteins such as the receptors for glucagon-like peptide-1 (GLP-1), gastric inhibitory polypeptide (GIP) and/or glucagon (GCG). These interventions have revolutionized the treatment of obesity and represent first-line pharmacotherapeutic strategies. One major weakness to these strategies is that once drug treatment stops, most patients are unable to maintain the new body weight setpoint, often gaining weight back rapidly. Thus, the identification of new therapies that focus on the ability to maintain homeostatic setpoint are necessary. The glucocorticoid receptor (GR) has been implicated in several pathways including reward-seeking, inflammation, stress and energy balance. Here, we investigated the effects of 30 days treatment with PT150 (40 mg/kg), a novel GR antagonist, alone and in combination with semaglutide (30 nmol/kg) on food intake, glucose homeostasis, body weight and setpoint maintenance using a C57Bl/6 diet-induced obesity (DIO) mouse model. We monitored food intake and body weight throughout treatment and after drug washout for 20 days to evaluate defended body weight maintenance (body weight setpoint). Our results indicate that treatment with PT150 alone does not significantly alter body weight but in combination with semaglutide it shows the most promising effects in body weight reduction and homeostatic setpoint maintenance. Together, these data suggest that PT150, a GR modulator, may be effective as a homeostatic setpoint modulator when combined with semaglutide.

SGLT2 inhibitor (SGLT2i)-induced diabetic hyperketonemia is a life-threatening acute complication of diabetes. While Celastrol has been reported to exert beneficial effects on obesity; its potential role in ketogenesis remains unclear. In this study, Celastrol administration significantly attenuates the fasting-induced elevation of blood {beta}-hydroxybutyrate. Moreover, a 7-day course of Celastrol (1 mg/kg/day) leads to reductions in body weight and fat mass. Mechanistically, Celastrol specifically downregulates HMGCS2 expression and suppressess hepatic ketogenesis through inhibiting PPAR expression in the short term ([&le;] 2 days). However, after prolonged treatment for 7 days, Celastrol modulates both PPARand serum free fatty acids (FFAs) levels. Furthermore, anti-ketogenic effect of Celastrol is abolished in Ppar{square} /{square} mice. Importantly, Celastrol effectively ameliorates SGLT2i-induced hyperketonemia. In summary, Celastrol curbs hepatic ketone overproduction in a PPAR-dependent manner, indicating its protective potential against SGLT2i-induced hyperketonemia.

BackgroundPolycystic ovary syndrome (PCOS) is a prevalent endocrine disorder with complex pathophysiology and limited therapeutic options. Identifying key molecular drivers and potential drug candidates is critical for improving clinical outcomes. MethodsWe integrated multi-cohort transcriptomics (GSE155489, GSE138518, GSE226146) with weighted gene co-expression network analysis (WGCNA), protein-protein interaction (PPI) network analysis, and drug repurposing. Differential expression analysis identified 1,039 DEGs, and WGCNA identified 10 PCOS-associated modules. Intersection of DEGs with module genes yielded 498 core candidate genes, which were subjected to functional enrichment, PPI network analysis, and connectivity map-based drug repurposing (CLUE/LINCS). Candidate drugs were further evaluated by molecular docking and ADMET prediction using a triple intersection strategy (hub genes, high differential expression, drug-target evidence). ResultsFunctional enrichment revealed significant enrichment in cell adhesion and TGF-beta signaling. PPI network analysis identified CD44 as the top hub gene (degree=42). Drug repurposing identified 106 candidate drugs, including troglitazone and enzalutamide. Using the triple intersection strategy, five genes (ID2, NR4A1, GJA5, ID1, MYH11) were prioritized for molecular docking. GJA5 showed strong predicted binding affinity with flufenamic acid (-7.88 kcal/mol), and cytosporone B exhibited favorable druglikeness (0 Lipinski violations). ConclusionThis study systematically characterizes PCOS-associated gene networks and provides a prioritized set of candidate targets and drugs through a purely computational framework. CD44 emerges as a key network node with potential relevance in PCOS pathophysiology. These findings offer testable hypotheses for future mechanistic studies and drug discovery efforts in PCOS.

IntroductionThe bidirectional relationship between depression and type 2 diabetes (T2D) is well-established. Women are disproportionately affected by their co-occurrence, particularly during midlife, yet sex- and age-specific studies on phenotypic and mechanistic factors underlying risk for their co-occurrence are limited. The purpose of this study was to identify combined risk profiles (i.e., depression, T2D) in women during midlife and to determine if microRNAs (miRs) that are associated with high-risk profiles provide mechanistic insights into multimorbidity. Materials and MethodsThis study included baseline data from women during midlife (ages 40-64 years) who participated in the Diabetes Prevention Program (DPP) (n = 603). Unsupervised k-means clustering was used to identify multimorbid risk profiles. Clinical characteristics included for risk profiling included Beck Depression Inventory (BDI-I), age, BMI, waist circumference, triglycerides, high HDL, FBG, and HbA1c. Associations between risk profiles and individual miRs and principal components of co-expressed miRs were determined via logistic regression models adjusted for participant race and ethnicity. False discovery rate (q< 0.05) was used to control for multiple comparisons. ResultsTwo distinct profiles were identified, with the high-risk profile characterized by younger age yet higher adiposity, glycemic biomarkers, and depression symptom burden compared to the low-risk profile. MiR-320a and miR-320c were associated with increased odds of high-risk profile assignment, and a co-expression cluster enriched for miRs belonging to the miR-320 family (PC3) was significantly associated with increased odds of high-risk profile assignment. Across all models, Black race demonstrated at least threefold higher odds of high-risk profile assignment. DiscussionThese findings highlight distinct multimorbid risk profiles in women during midlife, emphasizing the potential utility of integrated, multidimensional approaches for risk stratification. Findings also revealed mechanisms that may underly risk for co-occurrence of T2D and depression in women during midlife and potential therapeutic targets for prevention and treatment.

Background: C-terminal binding protein 2 (CtBP2) has been implicated in metabolic regulation, but its association with specific measures of adiposity and lipid profiles in humans remains unclear. This study examined the relationship between circulating CtBP2 levels and key components of metabolic syndrome, focusing on body fat distribution and lipid markers. Methods: Data from 508 participants (259 men, 249 women) from a publicly available dataset were analyzed. Serum CtBP2 concentrations were measured using ELISA. Associations with obesity markers (BMI, waist circumference, waist-to-hip ratio) and lipid profiles (triglycerides, HDL cholesterol) were assessed using Spearman correlation and linear regression, adjusting for age and sex. Results: CtBP2 levels showed weak but statistically significant positive correlations with all measures of adiposity, with the strongest association observed for waist circumference ({rho} = 0.150, p < 0.001), followed by BMI ({rho} = 0.120, p = 0.007) and waist-to-hip ratio ({rho} = 0.098, p = 0.027). No significant correlations were found with triglycerides or HDL cholesterol. In the regression model predicting BMI, age, and sex were significant predictors, while CtBP2 demonstrated a trend toward association ({beta} = 0.080, p = 0.052). Conclusion: Circulating CtBP2 appears to be modestly associated with measures of adiposity, particularly abdominal fat, but not with lipid abnormalities. These findings suggest a potential role for CtBP2 in obesity-related metabolic dysregulation and underscore the need for further mechanistic studies to clarify its clinical relevance.