[Effect of Rhein on the development of hepatic fibrosis in rats].

Objective: To investigate the effect of rhein on the development of hepatic fibrosis.
Methods: The animal models were made with carbon tetrachloride (CCl(4)) mixed with vegetable oil (3/2, v/v), which was injected subcutaneously twice a week for 6 weeks, and with 5% ethanol for free drinking water. At the same time, Rhein was administrated at the dose of 25 mg/kg or 100 mg/kg once a day for 6 weeks. The changes of both biochemical markers, such as the levels of alanine aminotransferase (ALT), hyaluronic acid (HA), procollagen type III (PCIII) in serum and SOD, malondialdehyde (MDA) in liver, and related histopathological parametres were determined.
Results: Compared with the model group, there were three kinds of changes in the larger quantity of rhein treated group. (1) The levels of ALT, HA, PCIII in serum and MDA in liver homogenate were decreased significantly (from 150 U/L +/- 16 U/L to 78 U/L +/- 18 U/L, 321 microg/L +/- 97 microg/L to 217 microg/L +/- 75 microg/L, 31 microg/L +/- 14 microg/L to 16 microg/L +/- 6 microg/L and 3.67 nmol/mg +/- 0.68 nmol/mg to 1.88 nmol/mg +/- 0.34 nmol/mg, respectively, t > or 2.977, P<0.01). However the level of SOD in liver was increased (from 62.45 NU/mg +/- 8.74 NU/mg to 91.26 NU/mg +/- 14.04 NU/mg, t=4.453, P<0.01). (2) The expressions of transforming growth factor beta 1 (TGF-beta 1) and alpha-smooth muscle actin (alpha-SMA) in liver were markedly reduced (P<0.05 and P<0.01). (3) The collagen staining positive area was decreased and the grade of fibrosis was reduced significantly in liver (P<0.05 and P<0.01).
Conclusion: Rhein can protect hepatocyte from injury and prevent the progress of hepatic fibrosis in rats, which may associate with that rhein plays a role in antioxidation, anti-inflammation, inhibiting the expression of TGF-beta1 and suppressing the activation of hepatic stellate cells (HSCs).