Abstract
Doxorubicin (DXR) is an anthracycline antibiotic that is commonly used in cancer treatment. The purpose of this study was to see if Thymoquinone (THY) could reduce the hepatotoxic effects of doxorubicin. All animals were divided into four groups: control (Phosphate buffer i.p. 0.5mlkg(-1)/day), THY (10mgkg(-1)/i.p/daily), doxorubicin (20mgkg(-1)/i.p/single dose), THY (10mgkg(-1)/i.p/daily) + DOX(20mgkg(-1)/i.p/single dose on Day 7). Changes in hepatic enzymes in serum ALT, AST, and GGT, as well as tests for free radical metabolism enzymes such as Cu, Zn-SOD, CAT, and MDA were carried out in all animals that received treatments. In addition, the inflammatory markers IL-6, Nf-kB, and TNF-alpha were measured in liver tissue homogenate. Caspase, an apoptosis marker, was also measured. The liver enzymes were significantly elevated in DOX freated rats as compared to all freated groups. Thymoquinone pretreatment significantly reduced the level of hepatic enzymes as compared to DOX. Comparison of the DOX-freated group to the control group showed that SOD and catalase activities rose significantly. In the DOX-freated group, malondialdehyde levels were higher than in the control and all-treatment groups, respectively (P<0.05). The THY + DOX group had lower levels of malondialdehyde, SOD, and catalase activity than the DOX-group (P<0.05). Anti-inflammatory markers (IL-6 and TNF-alpha), as well as Caspase 3 (p<0.0001), reduced in THY-freated rats, were found to be significantly lower in THY-freated rats (P<0.0001). Biochemical findings were supported by histopathological studies. We conclude that by modulating ROS, inflammation, and apoptosis, thymoquinone significantly reduces DOX-induced hepatotoxicity in rats.