Quercus dilatata Lindl. ex Royle ameliorates BPA induced hepatotoxicity in Sprague Dawley rats

Quercus dilatata Lindl. ex Royle was evaluated for in vitro polyphenol content and antioxidant potential as well as in vivo protective role against bisphenol A (BPA) induced hepatotoxicity. The distilled water-acetone (QDDAE) and methanol-ethyl acetate (QDMEtE) extracts were standardized and administered in high (300 mg/kg body weight (BW) and low (150 mg/kg BW) doses to Sprague Dawley rats, injected with BPA (25 mg/kg BW). Silymarin (50 mg/kg BW) was used as positive control. Subsequently, blood and liver homogenates were collected after four weeks of treatment, and the defensive effects of both extracts against oxidative damage and genotoxicity were assessed via hematological and biochemical investigations, determination of endogenous expression of enzymes as well as levels of free radicals and comet assay. Between the two extracts, maximum phenolics (213 +/- 0.15 mu g gallic acid equivalent/mg dry extract (DE) and flavonoids (55.6 +/- 0.16 mu g quercetin equivalent/mg DE) content, DPPH scavenging activity (IC50: 8.1 +/- 0.5 mu g/ml), antioxidant capacity (53.7 +/- 0.98 mu g ascorbic acid equivalent (AAE)/mg DE) and reducing potential (228.4 +/- 2.4 mu g AAE/mg DE) were observed in QDMEtE. In in vivo analysis, a dose dependent hepatoprotective activity was exhibited by both the extracts. QDDAE demonstrated maximum reduction in levels of alanine transaminase (49.77 +/- 3.83 U/l), thiobarbituric acid reactant substances (33.46 +/- 0.70 nM/min/mg protein), hydrogen peroxide (18.08 +/- 0.01 ng/mg tissue) and nitrite (55.64 +/- 1.79 mu M/ml), along with decline in erythrocyte sedimentation rate (4.13 +/- 0.072 mm/h), histopathological injuries and DNA damage in BPA intoxicated rats as compared with QDMEtE. Likewise, QDDAE also significantly restored activity levels of endogenous antioxidants, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (POD) and GSH with values of 6.46 +/- 0.15 U/mg protein, 6.87 +/- 0.1 U/min, 11.94 +/- 0.17 U/min and 16.86 +/- 1.56 nM/min/mg protein, respectively. Comparative results were obtained for QDMEtE. In conclusion, the present study endorses the significant hepatoprotective potential of standardized extracts of Q. dilatata with known polyphenolics content and validates the traditional use of this plant in natural medicine to manage disorders like hepatotoxicity.