Project description:Transcriptional profiling of subcutaneous adipose tissue before and after 2 years of bariatric surgery. This type of surgery produce a masive weight loss in morbidly obese subjects, and improve the comorbidities associated to obesity. Goal was to determine the effects of bariatric surgery on the gene expression of subcutaneous adipose tissue.
Project description:Low-grade chronic inflammation plays an important role in the development of obesity and obesity-associated disorders such as insulin resistance, type 2 diabetes, the metabolic syndrome and atherosclerosis. One possible link between obesity and inflammation is the enhanced activation of circulating monocytes making them more prone to infiltration into the adipose and vascular tissues of obese persons. Furthermore, weight loss after bariatric surgery is associated with less inflammation. Transcriptome analysis of circulating monocytes from control and obese patients before and after bariatric surgery will potentially provide insights into the pathophysiology of obesity and associated disorders and supply biomarkers for diagnostic purpose. The cohort comprised 6 lean age-matched controls (BMI: 20.3±0.5 kg/m2, mean±SEM) and 18 obese individuals without clinical symptoms of cardiovascular disease (BMI: 45.1±1.4 kg/m2, P<0.001 compared with lean controls). These 18 morbidly obese subjects were referred to our hospital for bariatric surgery. Before they were included, individuals were evaluated by an endocrinologist, an abdominal surgeon, a psychologist and a dietician. Only after multidisciplinary deliberation, the selected patients received a laparoscopic Roux-en-Y gastric bypass. CD14+ monocytes were collected before and three months after bariatric surgery (BMI: 37.5±1.3 kg/m2, P<0.001 compared with before weight loss), total RNA was extracted and subjected to genome-wide expression analysis. Samples consisted of CD14+ monocytes from 6 lean controls and 18 morbidly obese patients before and three months after bariatric surgery. The 6 lean controls were also used to make 6 control pools.
Project description:Bariatric surgery is highly effective for the treatment of obesity in individuals without (OB ) and in those with type 2 diabetes (T2D ). However, whether bariatric surgery triggers similar or distinct molecular changes in OB and T2D remains unknown. Given that individuals with type 2 diabetes often exhibit more severe metabolic deterioration, we hypothesized that bariatric surgery induces distinct molecular adaptations in skeletal muscle, the major site of glucose uptake, of OB and T2D after surgery-induced weight loss. All participants (OB, n=13; T2D, n=13) underwent detailed anthropometry before and one year after the surgery. Skeletal muscle biopsies were isolated at both time points and subjected to transcriptome and methylome analyses using a comprehensive bioinformatic pipeline.
Project description:Bariatric surgery is highly effective for the treatment of obesity in individuals without (OB ) and in those with type 2 diabetes (T2D ). However, whether bariatric surgery triggers similar or distinct molecular changes in OB and T2D remains unknown. Given that individuals with type 2 diabetes often exhibit more severe metabolic deterioration, we hypothesized that bariatric surgery induces distinct molecular adaptations in skeletal muscle, the major site of glucose uptake, of OB and T2D after surgery-induced weight loss. All participants (OB, n=13; T2D, n=13) underwent detailed anthropometry before and one year after the surgery. Skeletal muscle biopsies were isolated at both time points and subjected to transcriptome and methylome analyses using a comprehensive bioinformatic pipeline.
Project description:Low-grade chronic inflammation plays an important role in the development of obesity and obesity-associated disorders such as insulin resistance, type 2 diabetes, the metabolic syndrome and atherosclerosis. One possible link between obesity and inflammation is the enhanced activation of circulating monocytes making them more prone to infiltration into the adipose and vascular tissues of obese persons. Furthermore, weight loss after bariatric surgery is associated with less inflammation. Transcriptome analysis of circulating monocytes from control and obese patients before and after bariatric surgery will potentially provide insights into the pathophysiology of obesity and associated disorders and supply biomarkers for diagnostic purpose. The cohort comprised 6 lean age-matched controls (BMI: 20.3±0.5 kg/m2, mean±SEM) and 18 obese individuals without clinical symptoms of cardiovascular disease (BMI: 45.1±1.4 kg/m2, P<0.001 compared with lean controls). These 18 morbidly obese subjects were referred to our hospital for bariatric surgery. Before they were included, individuals were evaluated by an endocrinologist, an abdominal surgeon, a psychologist and a dietician. Only after multidisciplinary deliberation, the selected patients received a laparoscopic Roux-en-Y gastric bypass. CD14+ monocytes were collected before and three months after bariatric surgery (BMI: 37.5±1.3 kg/m2, P<0.001 compared with before weight loss), total RNA was extracted and subjected to genome-wide expression analysis.
Project description:Patients undergoing bariatric surgery are protected from subsequent breast cancer risk. It is unknown whether weight loss alone or surgery-specific alterations mediate risk reduction. We examined breast cancer in a pre-clinical model of diet induced obesity (DIO) followed by vertical sleeve gastrectomy (VSG) or dietary weight loss. DIO exacerbated tumor progression compared to lean controls, while VSG-induced weight loss reversed this exacerbation. However, dietary interventions were more effective than VSG despite similar reductions in weight and adiposity, potentially due to elevated immunosuppression after VSG. In tumor bearing mice, anti-PD-L1 immunotherapy after VSG improved anti-tumor immunity and potently impaired tumor progression. Thus, weight loss before tumor onset was protective regardless of intervention. Importantly, immunotherapy specifically improved outcomes in VSG.
Project description:Patients undergoing bariatric surgery are protected from subsequent breast cancer risk. It is unknown whether weight loss alone or surgery-specific alterations mediate risk reduction. We examined breast cancer in a pre-clinical model of diet induced obesity (DIO) followed by vertical sleeve gastrectomy (VSG) or dietary weight loss. DIO exacerbated tumor progression compared to lean controls, while VSG-induced weight loss reversed this exacerbation. However, dietary interventions were more effective than VSG despite similar reductions in weight and adiposity, potentially due to elevated immunosuppression after VSG. In tumor bearing mice, anti-PD-L1 immunotherapy after VSG improved anti-tumor immunity and potently impaired tumor progression. Thus, weight loss before tumor onset was protective regardless of intervention. Importantly, immunotherapy specifically improved outcomes in VSG.
Project description:The mechanisms of weight loss and metabolic improvements following bariatric surgery in skeletal muscle are not well known, however epigenetic modifications are likely to contribute. The aim of our study was to investigate skeletal muscle DNA methylation after weight loss induced by Roux-en-Y gastric bypass (RYGB) surgery.
Project description:Prevalence of obesity and associated diseases, including type 2 diabetes mellitus, dyslipidaemia and non-alcoholic fatty liver disease (NAFLD), are increasing. Underlying mechanisms, especially in humans, are unclear. Bariatric surgery provides the unique opportunity to obtain biopsies and portal vein blood-samples.
Methods
The BARIA Study aims to assess how microbiota and their metabolites affect transcription in key tissues and clinical outcome in obese subjects and how baseline anthropometric and metabolic characteristics determine weight loss and glucose homeostasis after bariatric surgery. We phenotype patients undergoing bariatric surgery (predominantly laparoscopic Roux-en-Y gastric bypass), before weight loss, with biometrics, dietary and psychological questionnaires, mixed meal test (MMT) and collect fecal-samples and intra-operative biopsies from liver, adipose tissues and jejunum. We aim to include 1500 patients. A subset (approximately 25%) will undergo intra-operative portal vein blood-sampling. Fecal-samples are analyzed with shotgun metagenomics and targeted metabolomics, fasted and postprandial plasma-samples are subjected to metabolomics, and RNA is extracted from the tissues for RNAseq-analyses. Data will be integrated using state-of-the-art neuronal networks and metabolic modeling. Patient follow-up will be ten years.
Project description:Background: Low-density neutrophils (LDN) are increased in several inflammatory diseases, and may also play a role in low-grade chronic inflammation in obesity. Yet their role in obesity or the effect of bariatric surgery-induced weight loss is unknown. Methods: We compared circulating LDN, their function, and gene expression between morbidly obese patients (MOP; BMI > 40 Kg/m2) and normal-weight controls (NWC; BMI < 25 Kg/m2) in a case-control study. Additionally, in a prospective longitudinal study, we measure changes in the frequency of LDN before and after bariatric surgery, and tested possible associations with metabolic and inflammatory parameters. Findings: LDN and inflammatory markers were significantly increased in MOP (n=27) compared to NWC (n=20). Transcriptome analysis of LDN from MOP showed an increased neutrophil-related gene expression signature associated with inflammation, neutrophil activation, and immunosuppressive function. However, LDN did not suppress T cells proliferation and produced low levels of ROS. Circulating LDN in MOP significantly decreased after surgery in parallel with BMI, metabolic syndrome and inflammatory markers. Interpretation: Obesity increases LDN with inflammatory gene signature. Bariatric surgery has anti-inflammatory effect including reduction of LDN. Gene expression and phenotype suggest that LDN represent a neutrophil subset that may be associated with obesity-associated chronic inflammation that promotes co-morbidities.