Turmeric extract and its active compound, curcumin, protect against chronic CCl4-induced liver damage by enhancing antioxidation

Abstract

Background: Curcumin, a major active component of turmeric, has previously been reported to alleviate liver damage. Here, we investigated the mechanism by which turmeric and curcumin protect the liver against carbon tetrachloride (CCl4)-induced injury in rats. We hypothesized that turmeric extract and curcumin protect the liver from CCl4-induced liver injury by reducing oxidative stress, inhibiting lipid peroxidation, and increasing glutathione peroxidase activation.

Methods: Chronic hepatic stress was induced by a single intraperitoneal injection of CCl4 (0.1 ml/kg body weight) into rats. Turmeric extracts and curcumin were administered once a day for 4 weeks at three dose levels (100, 200, and 300 mg/kg/day). We performed ALT and AST also measured of total lipid, triglyceride, cholesterol levels, and lipid peroxidation.

Result: We found that turmeric extract and curcumin significantly protect against liver injury by decreasing the activities of serum aspartate aminotransferase and alanine aminotransferase and by improving the hepatic glutathione content, leading to a reduced level of lipid peroxidase.

Conclusions: Our data suggest that turmeric extract and curcumin protect the liver from chronic CCl4-induced injury in rats by suppressing hepatic oxidative stress. Therefore, turmeric extract and curcumin are potential therapeutic antioxidant agents for the treatment of hepatic disease.

Keywords: Carbon tetrachloride; Curcumin; Glutathione; Lipid peroxidase; Oxidative stress.

Fig. 1

Turmeric extract and curcumin reduce AST and ALT levels in CCl₄-induced hepatic failure. Rats were intraperitoneally injected with CCl₄ (0.1 mL/100 g body weight) every other day for 4 weeks. Turmeric extract (100, 200, and 300 mg/kg) and curcumin (200 mg/kg) were given once daily. Liver and blood samples were collected from all sacrificed animals. Serum levels of AST (a) and ALT (b) were determined. ^# p < 0.05 vs. the CCl₄ group

Fig. 2

Turmeric extract and curcumin protect the liver from CCl₄-induced damage and lipid accumulation. Rats were intraperitoneally injected with CCl₄ (0.1 mL/100 g body weight) every other day for 4 weeks. Turmeric extract (100, 200, and 300 mg/kg) and curcumin (200 mg/kg) were given once daily. Liver and blood samples were collected from all sacrificed animals. Liver tissue was fixed and stained with Oil Red O

Fig. 3

Turmeric extract and curcumin protect the liver from CCl₄-induced lipid peroxidation. Rats were intraperitoneally (i.p.) injected with CCl₄ (0.1 mL/100 g body weight) every other day for 4 weeks. Turmeric extract (100, 200, and 300 mg/kg) and curcumin (200 mg/kg) were given once daily. After liver samples were collected from all sacrificed animals, the levels of lipid peroxidation (a) and MDA + 4-HNE (b) were measured. ^# p < 0.05 vs. the CCl₄ group

Fig. 4

Turmeric extract and curcumin protect the liver from CCl₄-induced oxidative stress. Rats were intraperitoneally injected with CCl₄ (0.1 mL/100 g body weight) every other day for 4 weeks. Turmeric extract (100, 200, and 300 mg/kg) and curcumin (200 mg/kg) were given once daily. After liver samples were collected from all sacrificed animals, the levels of SOD (a) and GPx (b) were measured. ^# p < 0.05 vs. the CCl₄ group

Fig. 5

Turmeric extract and curcumin protect the liver from CCl₄-induced ROS production. Rats were intraperitoneally injected with CCl₄ (0.1 mL/100 g body weight) every other day for 4 weeks. Turmeric extract (100, 200, and 300 mg/kg) and curcumin (200 mg/kg) were given once daily. a Liver tissue was isolated and loaded with 5 μM dihydroethidium. Fluorescence images were acquired. b Quantitative fluorescence density data. ^# p < 0.05 vs. the CCl₄ group

Fig. 6

Turmeric extract and curcumin protect the liver from CCl₄-induced oxidative stress. Rats were intraperitoneally injected with CCl₄ (0.1 mL/100 g body weight) every other day for 4 weeks. Turmeric extract (100, 200, and 300 mg/kg) and curcumin (200 mg/kg) were given once daily. a Livers were isolated and the levels of reduced glutathione (GSH) (a) and the GSH/GSSG ratios (b) were determined. ^# p < 0.05 vs. the CCl₄ group