Protective effects of Fraxinus xanthoxyloides (Wall.) leaves against CCl4 induced hepatic toxicity in rat

Abstract

Background: Leaves and root bark of Fraxinus xanthoxyloides Wall. (Oleaceae) are used locally for the treatment of jaundice, malaria and pneumonia. Decoction of stem, twigs and bark is used in pain, internal injuries, rheumatism and in bone fracture. In this investigation we have evaluated the methanol extract of leaves for its hepatoprotective potential against CCl₄ induced hepatic injuries in rat.

Methods: Powder of F. xanthoxyloides leaves was extracted with methanol (FXM) and subjected for the determination of polyphenolics through HPLC-DAD analysis. Sprague-Dawley (Rattus novergicus) male rats were divided into eight groups (six rats in each). Group I: non-treated control; Group II: vehicle treated (DMSO plus olive oil) while Group III- VI treated with 1 ml/kg body weight (bw) of CCl₄ (30 % in olive oil) for 30 days (15 dosages) to induce the hepatic injuries. Group IV: treated with silymarin (100 mg/kg bw); Group V and VI with FXM (200, 400 mg/kg bw) on alternate days with CCl₄ treatment. Group VII and VIII was administered with FXM (200, 400 mg/kg bw) alone (15 dosages). After 30 days the serum was evaluated for liver function enzymes and biochemical markers, liver samples for antioxidant enzymes, biochemical markers, comet assay and for histopathology.

Results: HPLC-DAD analysis of FXM revealed the existence of rutin and caffeic acid. In CCl₄ treated rats the level of alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin was significantly increased while the albumin concentration in serum was decreased as compared to control group. The level of hepatic antioxidant enzymes, catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), glutathione-S-transferase (GST) and glutathione reductase (GSR) was significantly decreased against the control group. Further, significant decrease in GSH while increase in lipid peroxides (TBARS), H₂O₂, DNA damages and comet length was induced with CCl₄ in hepatic tissues of rat. In contrast, co-administration of FXM and silymarin restored the biochemical and histopathological status of the liver.

Conclusion: Results of present investigation revealed that F. xanthoxyloides leaves possibly protect the liver against CCl₄ induced injuries like silymarin by its antioxidant constituents.

Keywords: Antioxidant; CCl4; Fraxinus xanthoxyloides; Lipid peroxidation; Liver; Phenolics.

Fig. 1

HPLC-DAD profile of the crude methanol extract of F. xanthoxyloides (FXM)

Fig. 2

Comet studies of hepatic tissues. Ethidium bromide stain; 40× (a) Untreated control (b) vehicle treated (DMSO + olive oil) (c) CCl₄ treated (d) CCl₄ + silymarin (100 mg/kg) treated (e) CCl₄ + FXM (200 mg/kg) treated (f) CCl₄ + FXM (400 mg/kg) treated (g) FXM (200 mg/kg) treated (h) FXM (400 mg/kg) treated rats. FXM; F. xanthoxyloides leaves methanol extract

Fig. 3

Histopathological studies of liver. Hematoxylin and eosin stain; 40× (a) Untreated control showing normal histoarchitecture of the hepatic tissues (b) vehicle treated (DMSO + olive oil) showing normal histoarchitecture of the hepatic tissues (c) CCl₄ treated showing macrosteatosis (d) CCl₄ + silymarin (100 mg/kg) treated showing almost normal histoarchitecture (e) CCl₄ + FXM (200 mg/kg) treated showing microsteatosis (f) CCl₄ + FXM (400 mg/kg) treated showing mild microsteatosis (g) FXM (200 mg/kg) treated showing normal histoarchitecture of the hepatic tissues (h) FXM (400 mg/kg) treated showing normal histoarchitecture of the hepatic tissues of rat. FXM; F. xanthoxyloides leaves methanol extract