Mice lacking C1q are protected from high fat diet-induced hepatic insulin resistance and impaired glucose homeostasis.

Complement activation is implicated in the development of obesity and insulin resistance, and loss of signaling by the anaphylatoxin C3a prevents obesity-induced insulin resistance in mice. Here we have identified C1q in the classical pathway as required for activation of complement in response to high fat diets. After 8 weeks of high fat diet, wild-type mice became obese and developed glucose intolerance.

Ethanol-induced oxidative stress via the CYP2E1 pathway disrupts adiponectin secretion from adipocytes.

Background: Adipose tissue is an important target for ethanol action. One important effect of ethanol is to reduce the secretion of adiponectin from adipocytes; this decrease is associated with lowered circulating adiponectin in rodent models of chronic ethanol feeding. Adiponectin is an insulin-sensitizing, anti-inflammatory adipokine; decreased adiponectin activity may contribute to tissue injury in response to chronic ethanol.

Identification of a cytochrome P4502E1/Bid/C1q-dependent axis mediating inflammation in adipose tissue after chronic ethanol feeding to mice.

Chronic, heavy alcohol exposure results in inflammation in adipose tissue, insulin resistance, and liver injury. Here we have identified a CYP2E1/Bid/C1q-dependent pathway that is activated in response to chronic ethanol and is required for the development of inflammation in adipose tissue. Ethanol feeding for 25 days to wild-type (C57BL/6J) mice increased expression of multiple markers of adipose tissue inflammation relative to pair-fed controls independent of increased body weight or adipocyte size.

Taurine supplementation prevents ethanol-induced decrease in serum adiponectin and reduces hepatic steatosis in rats.

Unlabelled: Chronic ethanol feeding decreases expression of adiponectin by adipocytes and circulating adiponectin. Adiponectin treatment during chronic ethanol feeding prevents liver injury in mice. Chronic ethanol feeding also increases oxidative and endoplasmic reticulum (ER) stress in adipose tissue.

Methods to investigate the effects of chronic ethanol on adipocytes.

Chronic ethanol consumption dysregulates glucose and lipid homeostasis, is associated with insulin resistance, and alters serum levels of adipokines including adiponectin and tumor necrosis factor-alpha. However, the mechanisms involved in these chronic ethanol-induced pathologies are not fully understood. Adipose tissue has been implicated as an important contributor to chronic ethanol-induced disease states and, therefore, the effects of chronic ethanol feeding in rats on adipocytes has been investigated.

Chronic ethanol and triglyceride turnover in white adipose tissue in rats: inhibition of the anti-lipolytic action of insulin after chronic ethanol contributes to increased triglyceride degradation.

Chronic ethanol consumption disrupts whole-body lipid metabolism. Here we tested the hypothesis that regulation of triglyceride homeostasis in adipose tissue is vulnerable to long-term ethanol exposure. After chronic ethanol feeding, total body fat content as well as the quantity of epididymal adipose tissue of male Wistar rats was decreased compared with pair-fed controls.

Chronic ethanol-induced insulin resistance is associated with macrophage infiltration into adipose tissue and altered expression of adipocytokines.

Background: Chronic ethanol consumption disrupts glucose homeostasis and is associated with the development of insulin resistance. While adipose tissue and skeletal muscle are the two major organs utilizing glucose in response to insulin, the relative contribution of these two tissues to impaired glucose homeostasis during chronic ethanol feeding is not known. As other models of insulin resistance, such as obesity, are characterized by an infiltration of macrophages into adipose tissue, as well as changes in the expression of adipocytokines that play a central role in the regulation of insulin sensitivity, we hypothesized that chronic ethanol-induced insulin resistance would be associated with increased macrophage infiltration into adipose tissue and changes in the expression of adipocytokines by adipose tissue.

Chronic ethanol feeding to rats decreases adiponectin secretion by subcutaneous adipocytes.

Chronic ethanol feeding to mice and rats decreases serum adiponectin concentration and adiponectin treatment attenuates chronic ethanol-induced liver injury. Although it is clear that lowered adiponectin has pathophysiological importance, the mechanisms by which chronic ethanol decreases adiponectin are not known. Here, we have investigated the impact of chronic ethanol feeding on adiponectin expression and secretion by adipose tissue.

Decreased insulin-dependent glucose transport by chronic ethanol feeding is associated with dysregulation of the Cbl/TC10 pathway in rat adipocytes.

Heavy alcohol consumption is an independent risk factor for type 2 diabetes. Although the exact mechanism by which alcohol contributes to the increased risk is unknown, impaired glucose disposal is a likely target. Insulin-stimulated glucose disposal in adipocytes is regulated by two separate and independent pathways, the PI3K pathway and the Cbl/TC10 pathway.

Chronic ethanol feeding impairs endothelin-1-stimulated glucose uptake via decreased G alpha 11 expression in rat adipocytes.

Chronic ethanol feeding decreases insulin-stimulated glucose uptake in rat adipocytes. Here, we show that chronic ethanol also decreases endothelin-stimulated glucose uptake. Endothelin-1 increased uptake of 2-deoxyglucose 2.