High-fat diet-induced muscle insulin resistance: relationship to visceral fat mass

Abstract

It has been variously hypothesized that the insulin resistance induced in rodents by a high-fat diet is due to increased visceral fat accumulation, to an increase in muscle triglyceride (TG) content, or to an effect of diet composition. In this study we used a number of interventions: fish oil, leptin, caloric restriction, and shorter duration of fat feeding, to try to disassociate an increase in visceral fat from muscle insulin resistance. Substituting fish oil (18% of calories) for corn oil in the high-fat diet partially protected against both the increase in visceral fat and muscle insulin resistance without affecting muscle TG content. Injections of leptin during the last 4 days of a 4-wk period on the high-fat diet partially reversed the increase in visceral fat and the muscle insulin resistance, while completely normalizing muscle TG. Restricting intake of the high-fat diet to 75% of ad libitum completely prevented the increase in visceral fat and muscle insulin resistance. Maximally insulin-stimulated glucose transport was negatively correlated with visceral fat mass (P < 0.001) in both the soleus and epitrochlearis muscles and with muscle TG concentration in the soleus (P < 0.05) but not in the epitrochlearis. Thus we were unable to dissociate the increase in visceral fat from muscle insulin resistance using a variety of approaches. These results support the hypothesis that an increase in visceral fat is associated with development of muscle insulin resistance.

Alcohol consumption promotes insulin sensitivity without affecting body fat levels

“…31,34 In their studies, however, rats consumed an ethanol-containing liquid diet, which contained high levels of fat. 32,34 Our results (Figure 3a) and those of others 19,35 show that a HFdiet can induce insulin resistance. Therefore, it is possible that the combination of alcohol and high lipid content in the liquid diet can lead to insulin resistance.…”

Effects of Korean white ginseng extracts on obesity in high-fat diet-induced obese mice

“…The present study investigated the anti-obesity effect of KGE in HFDinduced obese mice. It has previously been shown that HFD is a good strategy for inducing obesity (Kim et al 2000). The HFD thus leads to an increase in body weight, adipose tissue weight and hyperlipidemia in animals.…”

n-3 long chain polyunsaturated fatty acids: a nutritional tool to prevent insulin resistance associated to type 2 diabetes and obesity?

“…The following mechanisms are likely to be implicated: (a) the decrease in muscle triglyceride content. Indeed, it has been shown that insulin sensitivity is related to muscle triglycerides in rats fed a high fat diet and that muscle triglyceride content is decreased by fish oil [34,35]; (b) the decrease in LCFACoA as demonstrated by Neschen et al [36]; (c) the decrease in visceral fat mass [37]; (d) the increase in unsaturation of membrane phospholipids. A strong positive relationship has been shown between the insulin sensitivity of rat muscles and the degree of unsaturation of muscle membrane phospholipids [32].…”