Apoptosis of lymphocytes in allograft in a rat liver transplantation model induced by resveratrol

Aim: To study the effect of resveratrol (RES) on the apoptosis of lymphocytes in allograft in a rat liver transplantation model. Methods: Male Sprague-Dawley (SD) rats were selected as donors and male Wistar rats as recipients for a rejection model. The recipients were divided into four groups after orthotopic liver transplantation (OLTx). In the RES A, B, and C groups, RES was given intraperitoneally once a day (25, 50, and 100 mg kg(-1), respectively) after OLTx, whereas in the control group vehicle buffer was given intraperitoneally once a day. The survival period, lymphocytes apoptosis, expressions of Bcl-2/Bax proteins in lymphocytes, and histopathological findings were then compared among these groups. Results: The mean survival period after OLTx in RES C group was significantly longer than that in control group (P < 0.05). On the seventh post-transplant day, the apoptosis index (AI) of lymphocytes in portal area and the positive rate of Bax protein in lymphocytes in RES C group were significantly increased in comparison with those in control group (both P < 0.05), whereas there is no obvious difference in the expression of Bcl-2 protein in lymphocytes between the control group and various drug groups (all P < 0.05), and a histological examination revealed apparent difference in the severity of rejection between the RES C group and control group (P < 0.05). Conclusion: RES has an immunosuppressive effect on lymphocytes under allograft rejection in rat. Inducing apoptosis of lymphocytes and upregulating the ratio of Bax/bcl-2 proteins in lymphocytes in allograft liver may be part of the mechanisms. (c) 2006 Elsevier Ltd. All rights reserved.