Aqueous extract of Terminalia arjuna prevents carbon tetrachloride induced hepatic and renal disorders

Abstract

Background: Carbon tetrachloride (CCl4) is a well-known hepatotoxin and exposure to this chemical is known to induce oxidative stress and causes liver injury by the formation of free radicals. Acute and chronic renal damage are also very common pathophysiologic disturbances caused by CCl4. The present study has been conducted to evaluate the protective role of the aqueous extract of the bark of Termnalia arjuna (TA), an important Indian medicinal plant widely used in the preparation of ayurvedic formulations, on CCl4 induced oxidative stress and resultant dysfunction in the livers and kidneys of mice.

Methods: Animals were pretreated with the aqueous extract of TA (50 mg/kg body weight) for one week and then challenged with CCl4 (1 ml/kg body weight) in liquid paraffin (1:1, v/v) for 2 days. Serum marker enzymes, namely, glutamate pyruvate transaminase (GPT) and alkaline phosphatase (ALP) were estimated in the sera of all study groups. Antioxidant status in both the liver and kidney tissues were estimated by determining the activities of the antioxidative enzymes, superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST); as well as by determining the levels of thiobarbutaric acid reactive substances (TBARS) and reduced glutathione (GSH). In addition, free radical scavenging activity of the extract was determined from its DPPH radical quenching ability.

Results: Results showed that CCl4 caused a marked rise in serum levels of GPT and ALP. TBARS level was also increased significantly whereas GSH, SOD, CAT and GST levels were decreased in the liver and kidney tissue homogenates of CCl4 treated mice. Aqueous extract of TA successfully prevented the alterations of these effects in the experimental animals. Data also showed that the extract possessed strong free radical scavenging activity comparable to that of vitamin C.

Conclusion: Our study demonstrated that the aqueous extract of the bark of TA could protect the liver and kidney tissues against CCl4-induced oxidative stress probably by increasing antioxidative defense activities.

Figure 1

DPPH radical scavenging activity of aqueous TA extract in cell-free system. The curve is obtained by plotting various concentrations of the extract (μg/ml) against percent inhibition of DPPH radical. Vitamin C (VitC) has been used as a known DPPH radical scavenger.

Figure 2

Dose-dependent effect of aqueous TA extract on GPT level against CCl₄ induced toxicity. Cont: GPT level in normal mice, CCl₄: GPT level in CCl₄ treated mice, TA-1+CCl₄, TA-5+CCl₄, TA-10+CCl₄, TA-25+CCl₄, TA-50+CCl₄ and TA-100+CCl₄: GPT levels in extract treated mice applied for 7 days at a dose of 1, 5, 10, 25, 50 and 100 mg/kg body weight respectively before CCl₄ administration (1 ml/kg body weight). Each column represents mean ± SD, n = 6; (P* < 0.01, P** < 0.001).

Figure 3

Time-dependent effect of aqueous TA extract on GPT level against CCl₄ induced toxicity. Cont: GPT level in normal mice, CCl₄: GPT level in CCl₄ treated mice, TA-1D+CCl₄, TA-3D+CCl_4,TA-5D+CCl₄, TA-7D+CCl₄ and TA-10D+CCl₄: GPT levels in extract treated mice applied for 1, 3, 5, 7 and 10 days respectively at a dose of 50 mg/kg body weight before CCl₄ (1 ml/kg body weight) administration. Each column represents mean ± SD, n = 6; (P* < 0.01, P** < 0.001).

Figure 4

Effect of aqueous TA extract on ALP activity in blood serum and against CCl₄ intoxication (1 ml/kg body weight). Cont: ALP level in normal mice, CCl₄: ALP level in CCl₄ treated mice, TA+CCl₄: ALP level in which extract was given at a dose 50 mg/kg body weight prior to CCl₄ administration, VitE+CCl₄: ALP level in which vitamin E was given at a dose of 200 mg/kg body weight prior to CCl₄ administration. Each column represents mean ± SD, n = 6; (P* < 0.01, P** < 0.001).

Figure 5

Effect of aqueous TA extract on the SOD levels against CCl₄ induced hepatic and renal damages in mice. Aqueous extract of TA was administered orally 7 days prior to CCl₄ treatment (1 ml/kg body weight). For experimental detail, see the materials and methods. Left panel shows the effects of the extract on liver and right panel shows that on the kidney against CCl₄ induced SOD levels. Cont: SOD level in normal mice, CCl₄: SOD level in only CCl₄ treated mice, TA+CCl₄: SOD level in which extract was given at a dose 50 mg/kg body weight prior to CCl₄ administration, VitE+CCl₄: SOD level in which vitamin E was given at a dose of 200 mg/kg body weight prior to CCl₄ administration. Each column represents mean ± SD, n = 6; (P* < 0.01, P** < 0.001).

Figure 6

Effect of aqueous TA extract on the CAT levels in CCl₄ induced hepatic and renal damages in mice. Aqueous extract of TA was administered orally 7 days prior to CCl₄ treatment (1 ml/kg body weight). For experimental detail, see the materials and methods. Left panel shows the effects of the extract on liver and right panel shows that on the kidney against CCl₄ induced CAT levels. Cont: CAT level in normal mice, CCl₄: CAT level in only CCl₄ treated mice, TA+CCl₄: CAT level in which extract was given at a dose 50 mg/kg body weight prior to CCl₄ administration, VitE+CCl₄: CAT level in which vitamin E was given at a dose of 200 mg/kg body weight prior to CCl₄ administration. Each column represents mean ± SD, n = 6; (P* < 0.01, P** < 0.001).

Figure 7

Effect of aqueous TA extract on the GST levels in CCl₄ induced hepatic and renal damages in mice. Aqueous extract of TA was administered orally 7 days prior to CCl₄ treatment (1 ml/kg body weight). For experimental detail, see the materials and methods. Left panel shows the effects of the extract on liver and right panel shows that on the kidney against CCl₄ induced GST levels. Cont: GST level in normal mice, CCl₄: GST level in only CCl₄ treated mice, TA+CCl₄: GST level in which extract was given at a dose 50 mg/kg body weight prior to CCl₄ administration, VitE+CCl₄: GST level in which vitamin E was given at a dose of 200 mg/kg body weight prior to CCl₄ administration. Each column represents mean ± SD, n = 6; (P* < 0.01, P** < 0.001).

Figure 8

Effect of aqueous TA extract on the GSH levels in CCl₄ induced hepatic and renal damages in mice. Aqueous extract of TA was administered orally 7 days prior to CCl₄ treatment (1 ml/kg body weight). For experimental detail, see the materials and methods. Left panel shows the effects of the extract on liver and right panel shows that on the kidney against CCl₄ induced GSH levels. Cont: GSH level in normal mice, CCl₄: GSH level in only CCl₄ treated mice, TA+CCl₄: GSH level in which extract was given at a dose 50 mg/kg body weight prior to CCl₄ administration, VitE+CCl₄: GSH level in which vitamin E was given at a dose of 200 mg/kg body weight to CCl₄ administration. Each column represents mean ± SD, n = 6; (P* < 0.01, P** < 0.001).

Figure 9

Effect of aqueous TA extract on TBARS formation in CCl₄ induced hepatic and renal damages in mice. Aqueous extract of TAwas administered 7 days prior to CCl₄ treatment (1 ml/kg body weight). Left panel shows effects of the extract on liver and right panel shows that on the kidney against CCl₄ induced MDA contents. Cont: MDA content in normal mice, CCl₄: MDA content in only CCl₄ treated mice, TA+CCl₄: MDA level in which extract was given at a dose 50 mg/kg body weight prior to CCl₄ administration, VitE+CCl₄: MDA level in which vitamin E was given at a dose of 200 mg/kg body weight prior to CCl₄ administration. Each column represents mean ± SD, n = 6; (P* < 0.01, P** < 0.001).