Effects of licorice root ( <i>Glycyrrhiza glabra)</i> extract on the livers of obese rats*

We have investigated anti-obesity effects of the extract of licorice (<i>Glycyrrhiza glabra</i>) root in rats with diet-induced obesity and hyperlipidemia by using histopathological and biochemical methods. Thirty-two Wistar albino rats were divided to four groups of eight: normal control (C), high fat diet (HFD), high fat Diet + <i>Glycyrrhiza glabra</i> (HFD+M), and normal diet with <i>Glycyrrhiza glabra</i> (M). The high fat diet contained 300 g/kg fat (4000 kcal/kg); the daily dosage of <i>Glycyrrhiza glabra</i> extract was 1g/kg body weight by orogastric gavage. Supplementation of <i>Glycyrrhiza glabra</i> extract dramatically reduced increases in body weight caused by the induction of obesity. A hepatoprotective effect of <i>Glycyrrhiza glabra</i> extract was supported by the almost normal histology in the livers of the HFD+M rats, in contrast to the degenerative changes in the HFD rats, which included macrovesicular and microvesicular fat deposits, hydropic degeneration, dilatation of sinusoids and coagulation necrosis of some hepatocytes. Serum levels of alanine transaminase (ALT), aspartic transaminase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), cholesterol (HDL and LDL) and triglycerides, were ameliorated by <i>Glycyrrhiza glabra</i> extract treatment. We conclude that <i>Glycyrrhiza glabra</i> extract given together with HFD could prevent obesity and reduce liver damage in rats.