Histo-morphological assessments of the kidney and liver after Glycyrrhiza glabra extract administration in the rat

Glycyrrhiza glabra L. (family:Fabaceae:Leguminosae) is one of the important medicinal plant, commonly called as liquorice. Thirty-two Sprague-Dawley male rats were randomly distributed into four groups (n=8). Experimental groups were injected intra-peritoneally with aqueous extract of G. glabra at 50, 100 and 200 mg/kg/day, respectively, for 30 consecutive days while control group was injected with distilled water without any add-on material. At the end of the experiments, renal and hepatic tissue samples were taken and histo-morphological changes of the kidney and liver were examined using light microscope. In the rats administrated with G. glabra extract at different concentrations, the kidney showed massive congestion changes and a few necrosis of the nuclei in the epithelial cells of renal tubules. In addition, mild interstitial lymphoplasmacytic nephritis was seen in the kidney of the plant administrated groups. We observed dilation of urinary space in the renal glomerulus as well as dilation of various urinary tubules lumen in the kidney of the plant administrated groups. Hepatic structural changes included the decrease in diameter of hepatocytes, an increase of sinusoids volume (P<0.05), congestion and necrosis of hepatocytes in the liver of extract treated animals. In conclusion, however there are many documents exhibiting detoxification, antioxidation, and antiinfection properties of G. glabra, we observed some of the likely side effects of G. glabra on the kidney and liver structure in rats. So caution should be paid to popular consumption of this plant.