Licorice Extracts Attenuate Nephrotoxicity Induced by Brucine Through Suppression of Mitochondria Apoptotic Pathway and STAT3 Activation.

Licorice, one of the most widely used medicinal herbs in East Asia, has effects such as anti-inflammation, antioxidant, and detoxifying. This study aimed to evaluate the protective effect of licorice on brucine-induced nephrotoxicity. Sprague Dawley rats were administered with brucine intraperitoneally for 7 consecutive days with or without treatment with licorice. The content of blood urea nitrogen and creatinine in serum, the activities of superoxide dismutase and content of glutathione, malonaldehyde in kidney tissue were detected. Hematoxylin-eosin staining was employed to observe the histopathological changes of kidney. The expression and phosphorylation levels of protein were evaluated by Western blotting and immunohistochemical analysis. The results illustrated that treatment with licorice extracts (LE) significantly protected against the brucine-induced nephrotoxicity by reducing the content of blood urea nitrogen and serum creatinine, attenuating pathologic damage. The unbalance of oxidative stress was repaired by LE via increasing the level of glutathione, promoting the activities of superoxide dismutase and decreasing the content of malonaldehyde. In addition, LE overturned the influence of brucine on apoptosis-related protein and signal transducer and activator of transcription-3 (STAT3) activation. Taken together, these data demonstrate that licorice may attenuate brucine-induced nephrotoxicity via inactivation of oxidative stress and mitochondrial-mediated apoptosis pathway. More importantly, the renoprotective effects may be mediated, at least partly, by preventing the activation of STAT3 protein.