Effects of indole-3-carbinol on metabolic parameters and on lipogenesis and lipolysis in adipocytes 182

Abstract

: Indole-3-carbinol (I3C) was found to have possible anticarcinogenic, antioxidant and anti-atherogenic effects on the organism. So far, its influence on metabolic pathways has been unknown. This work was the first attempt to determine the carbohydrate and lipid metabolism changes <I>in vivo</I> after administration of 150 mg/kg b.wt./day I3C to male rats. Additionally, the aim of this trial was to evaluate the direct effect of I3C on basal and hormone-induced lipogenesis and lipolysis in isolated rat adipocytes at concentrations 1, 10, 100 μM <I>in vitro</I>. We can corroborate that adipocytes are susceptible to the direct action of I3C. The incubation of adipocytes with I3C at the three above-mentioned concentrations resulted in its influence on restriction of glucose entry into adipocytes in the basal as well as insulin-stimulated conditions. However, it was observed that I3C at these concentrations strongly intensified basic and epinephrine-stimulated lipolysis. I3C also has a significant influence on metabolism <I>in vivo</I>. Its administration to rats caused a significant increase in the content of triglycerides and a decrease in glycogen in the liver. The considerable augmentation of glucose, triglycerides, cholesterol in high-density lipoprotein and insulin with a concomitant decrease in FFA concentrations was noted in the blood serum. I3C did not alter phospholipids, total, free, esterified cholesterol in the serum and the liver cholesterol. The results obtained <I>in vivo</I> and <I>in vivo</I> indicate that the effect of I3C is adverse for the majority of metabolic parameters which were investigated. The most important finding in this study is the effect of I3C on liver steatosis and that the observed lower lipogenesis at higher lipolysis in fat cells may be involved in the mechanism.