CORMONT , Mireille

Abstract Background The trafficking of cargoes from endosomes to the trans -Golgi network requires numerous sequential and coordinated steps. Cargoes are sorted into endosomal-derived carriers that are transported, tethered, and fused to the trans -Golgi network. The tethering step requires several complexes, including the Golgi-associated...

Inflammation is associated with obesity and insulin resistance. Proinflammatory cytokines produced by adipose tissue in obesity could alter insulin signaling and action. Recent studies have shown a relationship between IL-1beta level and metabolic syndrome or type 2 diabetes. However, the ability of IL-1beta to alter insulin signaling and...

Alteration of adipocyte function plays a key role in the pathogenesis of metabolic diseases such as insulin resistance and Type 2 Diabetes. This highlights the need to better understand the molecular mechanism involved in adipocyte dysfunction in order to develop new therapies against obesity-related diseases. Manipulating the expression of...

Metabolic stresses alter the signaling and actions of insulin in adipocytes during obesity, but the molecular links remain incompletely understood. Members of the microRNA-34 (miR-34 family play a pivotal role in stress response, and previous studies showed an upregulation of miR-34a in adipose tissue during obesity. Here, we identified miR-34a...

Metabolic stresses alter the signaling and actions of insulin in adipocytes during obesity, but the molecular links remain incompletely understood. Members of the microRNA-34 (miR-34 family play a pivotal role in stress response, and previous studies showed an upregulation of miR-34a in adipose tissue during obesity. Here, we identified miR-34a...

Obesity is a major worldwide public health issue that increases the risk to develop cardiovascular diseases, type-2 diabetes, and liver diseases. Obesity is characterized by an increase in adipose tissue (AT) mass due to adipocyte hyperplasia and/or hypertrophia, leading to profound remodeling of its three-dimensional structure. Indeed, the...

Adipose tissue is a source of hepatocyte growth factor (HGF), and circulating HGF levels have been associated with elevated body mass index in human. However, the effects of HGF on adipocyte functions have not yet been investigated. We show here that in 3T3-L1 adipocytes HGF stimulates the phosphatidylinositol (PI) 3-kinase-dependent protein...

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Little is known about the role of p38MAPK in human adipocyte differentiation. Here we showed that p38MAPK activity increases during human preadipocytes differentiation. Pharmacological inhibition of p38MAPK during adipocyte differentiation of primary human preadipocytes markedly reduced triglycerides accumulation and adipocyte markers...

International audience

International audience

Endosomal small GTPases of the Rab family, among them Rab4a, play an essential role in the control of the glucose transporter GLUT4 trafficking, which is essential for insulin-mediated glucose uptake. We found that adipocytes also expressed Rab4b and we observed a consistent decrease in the expression of Rab4b mRNA in human and mice adipose...

International audience

International audience

Low-grade chronic inflammation and reduced differentiation capacity are hallmarks of hypertrophic adipose tissue (AT) and key contributors of insulin resistance. We identified PPARGΔ5 as a dominant-negative splicing isoform overexpressed in the AT of obese/diabetic patients able to impair adipocyte differentiation and PPARγ activity in...

The implication of αβ and γδ T cells in obesity-associated inflammation and insulin resistance (IR) remains uncertain. Mice lacking γδ T cells show either no difference or a decrease in high-fat diet (HFD)-induced IR, whereas partial depletion in γδ T cells does not protect from HFD-induced IR. αβ T-cell deficiency leads to a decrease in white...

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OBJECTIVE: Obesity is characterized by an overgrowth of adipose tissue that leads to the formation of hypoxic areas within this tissue. We investigated whether this phenomenon could be responsible for insulin resistance by studying the effect of hypoxia on the insulin signaling pathway in adipocytes. RESEARCH DESIGN AND METHODS: The hypoxic...

OBJECTIVE Activation of extracellular signal–regulated kinase-(ERK)-1/2 by cytokines in adipocytes is involved in the alterations of adipose tissue functions participating in insulin resistance. This study aims at identifying proteins regulating ERK1/2 activity, specifically in response to inflammatory cytokines, to provide new insights into...

The adipose tissue may play an active role in systemic iron regulation and this role may be determinant in obese patients. Indeed, we reported previously that hepcidin, the iron‐regulatory hormone, is expressed in adipose tissue and its messenger RNA (mRNA) expression is increased in adipose tissue of morbidly obese patients. The objectives of...

Obesity modifies T cell populations in adipose tissue, thereby contributing to adipose tissue inflammation and insulin resistance. Here, we show that Rab4b, a small GTPase governing endocytic trafficking, is pivotal in T cells for the development of these pathological events. Rab4b expression is decreased in adipose T cells from mice and...

Activation of the p53 pathway in adipose tissue contributes to insulin resistance associated with obesity. However, the mechanisms of p53 activation and the impact on adipocyte functions are still elusive. Here we found a higher level of DNA oxidation and a reduction in telomere length in adipose tissue of high-fat diet mice and an increase in...