Publications

Sleep apnea is common but often underdiagnosed after stroke, hindering rehabilitation and functional recovery. Access to sleep studies remains limited for stroke patients, partly due to the inconvenience of current diagnostic tools. The widespread availability and built-in sensors of smartphones make them powerful solutions for mobile health applications, including sleep monitoring. This study aims to detect and evaluate sleep apnea in post-stroke patients using a smartphone and extract multimodal digital biomarkers to characterize their sleep patterns. For that, overnight sleep tests were conducted on 30 subacute stroke patients and 30 age- and sex-matched control subjects, using a smartphone-based system that recorded audio, accelerometer, and oximetry data. Signals were analyzed with custom-made algorithms to compute respiratory, oxygenation, and sleep position indices. Results showed that the apnea-hypopnea index (AHI) was significantly higher in the stroke than the control group (28 +/- 19 vs 14 +/- 11, p = 0.006). Moderate-to-severe sleep apnea (AHI >= 15) was present in 67% of stroke patients and 40% of control subjects. Stroke patients spent more time mouth breathing (22% vs 12%, p

JTD Keywords: Association, Biomedical signal processing, Entropy, Heart-rate, Ischemic-stroke, Mhealth, Monitoring, Obesity, Oximetry, Positions, Prediction, Prevalence, Sleep apnea, Smartphone, Stroke, Supine sleep, Wearables

Biological sex significantly influences the prevalence, incidence, and severity of numerous human diseases, yet it remains an underappreciated variable in biomedical research. Although sexually dimorphic genes contribute to sex-specific traits and disease manifestations, their regulation under metabolic stress is poorly understood. To explore sex-specific metabolic adaptations, we analyzed responses to high-fat diet (HFD)-induced obesity in male and female mice, focusing on the regulation of sex-biased genes. Despite similar adiposity, HFD-fed males displayed more severe metabolic impairments than females, highlighting divergent metabolic outcomes. To investigate the basis for these sex-specific differences, we performed whole transcriptomic profiling of liver and white adipose tissue (WAT) at early (2 wk) and late (12 wk) stages of HFD exposure. Our analysis revealed marked sex-specific gene expression changes across multiple categories, particularly pronounced in male WAT after prolonged HFD feeding. Strikingly, genes exhibiting sexual dimorphism under normal conditions were preferentially modulated in both sexes, comprising up to 46% of all HFD-regulated genes. This led to a substantial loss of sex-biased gene expression in both liver and WAT after HFD exposure, correlating with metabolic dysfunction. Male-biased genes associated with cilia function and estrogen response were among the most affected, showing significant downregulation in male WAT under HFD. Our findings provide a novel perspective on how obesity disrupts sex-specific gene expression in key metabolic tissues, particularly targeting sex-biased genes. By revealing that a considerable proportion of sex-biased genes exhibit HFD-regulated modulation, our study highlights the critical role of these genes in maintaining metabolic health. NEW & NOTEWORTHY Biological sex shapes metabolic tissue physiology, largely through sex-biased gene regulation. Our comprehensive transcriptomic analysis reveals that sex-biased genes in liver and white adipose tissue undergo the most significant regulation during obesity-driven metabolic dysfunction, resulting in a loss of their bias. This disruption highlights a previously unrecognized role of sex-biased genes in maintaining metabolic health in both males and females.

JTD Keywords: Er-alpha, Estrogen-receptor, Female, Gender-differences, High-fat-diet, Insulin resistance, Insulin-resistance, Mitochondrial-function, Obesity, Oxidative-metabolism, Sex differences, Sex-differences, Transcriptomics, Type 2 diabetes, White adipose-tissue

JTD Keywords: extracellular vesicles, microfluidic platforms, micrornas, obesity, plasma, rnas, Biomarkers, Mirnas

Many lines of evidence demonstrate a correlation between liver glycogen content and food intake. We previously demonstrated that mice overexpressing protein targeting to glycogen (PTG) specifically in the liver—which have increased glycogen content in this organ—are protected from high-fat diet (HFD)-induced obesity by reduced food intake. However, the use of PTG to increase liver glycogen implies certain limitations. PTG stimulates glycogen synthesis but also inhibits the enzyme responsible for glycogen degradation. Furthermore, as PTG is a regulatory subunit of protein phosphatase 1 (PP1), which regulates many cellular functions, its overexpression could have side effects beyond the regulation of glycogen metabolism. Therefore, it is necessary to determine whether the direct activation of glycogen synthesis, without affecting its degradation or other cellular functions, has the same effects. To this end, we generated mice overexpressing a non-inactivatable form of glycogen synthase (GS) specifically in the liver (9A-MGSAlb mice). Control and 9a-MGSAlb mice were fed a standard diet (SD) or HFD for 16 weeks. Glucose tolerance and feeding behavior were analyzed. 9A-MGSAlb mice showed an increase in hepatic glycogen in fed and fasting conditions. When fed an HFD, these animals preserved their hepatic energy state, had a reduced food intake, and presented a lower body weight and fat mass than control animals, without changes in energy expenditure. Furthermore, 9A-MGSAlb animals showed improved glucose tolerance when fed an SD or HFD. Moreover, liver triacylglycerol levels that were increased after HFD feeding were lower in these mice. These results confirm that increased liver glycogen stores contribute to decreased appetite and improve glucose tolerance in mice fed an HFD. On the basis of our findings, strategies to preserve hepatic glycogen stores emerge as potential treatments for obesity and hyperglycemia.

JTD Keywords: accumulation, atp, attenuates obesity, expression, food intake, glucose, glycogen, glycogen synthase, high-fat diet, homeostasis, hyperglycemia, liver, mgat1, muscle, protein, ptg, Glycogen, Hepatic overexpression, Liver

Introduction and aimsDietary polyphenols have long been associated with health benefits, including the prevention of obesity and related chronic diseases. Overfeeding was shown to rapidly induce weight gain and fat mass, associated with mild insulin resistance in humans, and thus represents a suitable model of the metabolic complications resulting from obesity. We studied the effects of a polyphenol-rich grape extract supplementation on the plasma metabolome during an overfeeding intervention in adults, in two randomized parallel controlled clinical trials.MethodsBlood plasma samples from 40 normal weight to overweight male adults, submitted to a 31-day overfeeding (additional 50% of energy requirement by a high calorie-high fructose diet), given either 2 g/day grape polyphenol extract or a placebo at 0, 15, 21, and 31 days were analyzed (Lyon study). Samples from a similarly designed trial on females (20 subjects) were collected in parallel (Lausanne study). Nuclear magnetic resonance (NMR)-based metabolomics was conducted to characterize metabolome changes induced by overfeeding and associated effects from polyphenol supplementation. The clinical trials are registered under the numbers NCT02145780 and NCT02225457 atResultsChanges in plasma levels of many metabolic markers, including branched chain amino acids (BCAA), ketone bodies and glucose in both placebo as well as upon polyphenol intervention were identified in the Lyon study. Polyphenol supplementation counterbalanced levels of BCAA found to be induced by overfeeding. These results were further corroborated in the Lausanne female study.ConclusionAdministration of grape polyphenol-rich extract over 1 month period was associated with a protective metabolic effect against overfeeding in adults.

JTD Keywords: branched chain amino acids, grape polyphenols, human trials, metabolism, metabolomics, nmr, obesity, Branched chain amino acids, Grape polyphenols, Human trials, Metabolism, Metabolomics, Nmr, Obesity, Overfeeding

Purpose : The nutritional intervention program “DiOGenes” focuses on how obesity can be prevented and treated from a dietary perspective. We generated differential plasma proteome profiles in the DiOGenes cohort to identify proteins associated with weight loss and maintenance and explore their relation to body mass index, fat mass, insulin resistance and sensitivity. Experimental Design : Relative protein quantification was obtained at baseline and after combined weight loss/maintenance phases using isobaric tagging and MS/MS. A Welch t-test determined proteins differentially present after intervention. Protein relationships with clinical variables were explored using univariate linear models, considering collection center, gender and age as confounding factors. Results : 473 subjects were measured at baseline and end of the intervention; 39 proteins were longitudinally differential. Proteins with largest changes were sex hormone-binding globulin, adiponectin, C-reactive protein, calprotectin, serum amyloid A, and proteoglycan 4 (PRG4), whose association with obesity and weight loss is known. We identified new putative biomarkers for weight loss/maintenance. Correlation between PRG4 and proline-rich acidic protein 1 (PRAP1) variation and Matsuda insulin sensitivity increment was showed. Conclusions and Clinical Relevance : MS-based proteomic analysis of a large cohort of non-diabetic overweight and obese individuals concomitantly identified known and novel proteins associated with weight loss and maintenance.

JTD Keywords: Biomarker, Diabetes, Large-scale study, Mass spectrometry, Obesity, Proteomics

Background: Intermittent hypoxia and obesity which are two pathological conditions commonly found in patients with obstructive sleep apnea (OSA), potentially enhance cancer progression. Objective: To investigate whether obesity and/or intermittent hypoxia (IH) mimicking OSA affect tumor growth. Methods: A subcutaneous melanoma was induced in 40 mice [22 obese (40-45 g) and 18 lean (20-25 g)] by injecting 10(6) B16F10 cells in the flank. Nineteen mice (10 obese/9 lean) were subjected to IH (6 h/day for 17 days). A group of 21 mice (12 obese/9 lean) were kept under normoxia. At day 17, tumors were excised, weighed and processed to quantify necrosis and endothelial expression of vascular endothelial growth factor (VEGF) and CD-31. VEGF in plasma was also assessed. Results: In lean animals, IH enhanced tumor growth from 0.81 +/- 0.17 to 1.95 +/- 0.32 g. In obese animals, a similar increase in tumor growth (1.94 +/- 0.18 g) was observed under normoxia, while adding IH had no further effect (1.69 +/- 0.23 g). IH only promoted an increase in tumoral necrosis in lean animals. However, obesity under normoxic conditions increased necrosis, VEGF and CD-31 expression in tumoral tissue. Plasma VEGF strongly correlated with tumor weight (rho = 0.76, p < 0.001) in the whole sample; it increased in lean IH-treated animals from 66.40 +/- 3.47 to 108.37 +/- 9.48 pg/mL, p < 0.001), while the high baseline value in obese mice (106.90 +/- 4.32 pg/mL) was unaffected by IH. Conclusions: Obesity and IH increased tumor growth, but did not appear to exert any synergistic effects. Circulating VEGF appeared as a crucial mediator of tumor growth in both situations.

JTD Keywords: Intermittent hypoxia, Obesity, Cancer, Sleep apnea, Animal model