Protective Effects of Crocin Against Hepatic Damages in D-galactose Aging Model in Rats

Aging is a progressive process which is associated with liver dysfunction and it is due to oxidative stress, inflammation, and cell apoptosis. Long-term D-galactose (D-gal) administration is able to develop an aging model in animals. Crocin as a major active ingredient in saffron has shown anti-inflammatory and hepatoprotective effects via its antioxidant capacity. Thus, the aim of the present study was the assessment of crocin effects on hepatic and metabolic disorders induced by D-gal in rats. Aging model was induced in rats by 56-day administration of D-gal (400 mg/kg/day subcutaneously). Protective effects of different doses of crocin (7.5, 15 and 30 mg/kg/day) in concomitant with D-gal administration were evaluated. Malondialdehyde (MDA) and reduced glutathione (GSH) amounts were measured by means of their reaction, respectively, with thiobarbituric acid and 5,5'-Dithiobis (2-nitrobenzoic acid) (DTNB) under a specific condition. Cyclooxygenase-2 (COX-2), β-galactosidase, induced nitric oxide synthase (iNOS), and carboxymethyllysine (CML) levels were determined by western blotting method. Additionally, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) were measured in serum. D-gal administration significantly elevated ALT, AST, ALP levels, which were markedly inhibited by crocin administration. Crocin suppressed the overgeneration of lipid peroxidation products such as MDA. iNOS was elevated by D-gal administration and was returned to the normal extent by crocin. Therefore, Crocin as a powerful antioxidant and radical scavenger, totally exhibited hepatoprotective effects against D-gal-induced toxicity in rats.