Search results for " insulin"
showing 10 items of 237 documents
Bisphenol-A impairs insulin action and up-regulates inflammatory pathways in human subcutaneous adipocytes and 3T3-L1 cells.
2013
Current evidence indicates that chemical pollutants may interfere with the homeostatic control of nutrient metabolism, thereby contributing to the increased prevalence of metabolic disorders. Bisphenol-A (BPA) is a lipophilic compound contained in plastic which is considered a candidate for impairing energy and glucose metabolism. We have investigated the impact of low doses of BPA on adipocyte metabolic functions. Human adipocytes derived from subcutaneous adipose tissue and differentiated 3T3-L1 cells were incubated with BPA, in order to evaluate the effect on glucose utilization, insulin sensitivity and cytokine secretion. Treatment with 1 nM BPA significantly inhibited insulin-stimulate…
Immune Cell Toll-like Receptor 4 Mediates the Development of Obesity- and Endotoxemia-Associated Adipose Tissue Fibrosis
2014
International audience; Adipose tissue fibrosis development blocks adipocyte hypertrophy and favors ectopic lipid accumulation. Here, we show that adipose tissue fibrosis is associated with obesity and insulin resistance in humans and mice. Kinetic studies in C3H mice fed a high-fat diet show activation of macrophages and progression of fibrosis along with adipocyte metabolic dysfunction and death. Adipose tissue fibrosis is attenuated by macrophage depletion. Impairment of Toll-like receptor 4 signaling protects mice from obesity-induced fibrosis. The presence of a functional Toll-like receptor 4 on adipose tissue hematopoietic cells is necessary for the initiation of adipose tissue fibros…
Serum γ-glutamyl transferase levels, insulin resistance and liver fibrosis in patients with chronic liver diseases.
2012
Background and Aims: Serum levels of γ-glutamyl-transpeptidase(γ-GT) were associated with liver disease severity and metabolic alterations, which in turn are able to affect hepatic damage. In patients with nonalcoholic fatty liver disease (NAFLD), genotype 1 chronic hepatitis C (G1CHC) and chronic hepatitis B (CHB), we assessed the link between liver fibrosis and γ-GT serum levels, and we evaluated if normal or high γ-GT serum levels affect the association between insulin resistance (IR) and severity of liver fibrosis. Methods: 843 consecutive patients with chronic liver disease (CLD)(193 NAFLD, 481 G1CHC, 169 CHB) were evaluated by liver biopsy (Kleiner and Scheuer scores) and clinical and…
HEPATITIS C AND DIABETES: THE INEVITABLE COINCIDENCE?
2009
Type 2 diabetes (T2D) and HCV infection are common conditions involving, respectively, at least 170 and 130 million people worldwide. However, the distribution of such cases does not overlap in the same age groups in different geographic areas. Following pioneering reports of increased prevalence of T2D in HCV-positive cirrhosis, interest concerning the relationship between HCV and T2D has escalated. HCV is able to induce insulin resistance (IR) directly and the role of specific viral genotypes responsible for such effect is disputed. IR has consistently been found to be closely linked to fibrosis in HCV infection, although also typically associated with T2D in prefibrotic stages. HCV infec…
Nrf2-interacting nutrients and COVID-19: time for research to develop adaptation strategies
2020
AbstractThere are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of …
Apelin treatment increases complete Fatty Acid oxidation, mitochondrial oxidative capacity, and biogenesis in muscle of insulin-resistant mice.
2012
Both acute and chronic apelin treatment have been shown to improve insulin sensitivity in mice. However, the effects of apelin on fatty acid oxidation (FAO) during obesity-related insulin resistance have not yet been addressed. Thus, the aim of the current study was to determine the impact of chronic treatment on lipid use, especially in skeletal muscles. High-fat diet (HFD)-induced obese and insulin-resistant mice treated by an apelin injection (0.1 μmol/kg/day i.p.) during 4 weeks had decreased fat mass, glycemia, and plasma levels of triglycerides and were protected from hyperinsulinemia compared with HFD PBS-treated mice. Indirect calorimetry experiments showed that apelin-treated mice…
Anti-inflammatory Lactobacillus rhamnosus CNCM I-3690 strain protects against oxidative stress and increases lifespan in Caenorhabditis elegans.
2012
International audience; Numerous studies have shown that resistance to oxidative stress is crucial to stay healthy and to reduce the adverse effects of aging. Accordingly, nutritional interventions using antioxidant food-grade compounds or food products are currently an interesting option to help improve health and quality of life in the elderly. Live lactic acid bacteria (LAB) administered in food, such as probiotics, may be good antioxidant candidates. Nevertheless, information about LAB-induced oxidative stress protection is scarce. To identify and characterize new potential antioxidant probiotic strains, we have developed a new functional screening method using the nematode Caenorhabdit…
Insulin-like peptides involved in photoperiodism in the aphid Acyrthosiphon pisum
2019
Aphids were the first animals reported as photoperiodic as their life cycles are strongly determined by the photoperiod. During the favourable seasons (characterised by long days) aphid populations consist exclusively of viviparous parthenogenetic females (known as virginoparae). Shortening of the photoperiod in autumn is perceived by aphids as the signal that anticipates the harsh season, leading to a switch in the reproductive mode giving place to the sexual morphs (oviparae females and males) that mate and lay winter-resistant (diapause-like) eggs. The molecular and cellular basis governing the switch between the two reproductive modes are far from being understood. Classical experiments…
Nose-to-brain delivery of insulin enhanced by a nanogel carrier.
2018
Recent evidences suggest that insulin delivery to the brain can be an important pharmacological therapy for some neurodegenerative pathologies, including Alzheimer disease (AD). Due to the presence of the Blood Brain Barrier, a suitable carrier and an appropriate route of administration are required to increase the efficacy and safety of the treatment. Here, poly(N-vinyl pyrrolidone)-based nanogels (NG), synthetized by e-beam irradiation, alone and with covalently attached insulin (NG-In) were characterized for biocompatibility and brain delivery features in a mouse model. Preliminarily, the biodistribution of the "empty" nanocarrier after intraperitoneal (i.p.) injection was investigated b…
Lipidomic profiling identifies signatures of metabolic risk
2020
Background: Metabolic syndrome (MetS), the clustering of metabolic risk factors, is associated with cardiovascular disease risk. We sought to determine if dysregulation of the lipidome may contribute to metabolic risk factors. Methods: We measured 154 circulating lipid species in 658 participants from the Framingham Heart Study (FHS) using liquid chromatography-tandem mass spectrometry and tested for associations with obesity, dysglycemia, and dyslipidemia. Independent external validation was sought in three independent cohorts. Follow-up data from the FHS were used to test for lipid metabolites associated with longitudinal changes in metabolic risk factors. Results: Thirty-nine lipids were…