Biochemical and molecular evaluation of the effect of some medicinal plant extracts on non-alcoholic fatty liver disease induced in rats

Abstract

The current study was designed to set the safe doses of the Foeniculum vulgare Mill., Foeniculum vulgare Mill.-defatted, Camellia sinensis and Vitis vinifera seed extracts. Moreover, this study was extended to explore the possible therapeutic potential of these medicinal plants in management of steatosis and steatohepatitis in the experimental model. For preparation of the selected medicinal plant extracts and fraction, the air-dried aerial part of Foeniculum vulgare Mill. (4 kg) were grinding pulverized to fine powder and extracted in a mixture of water and methanol 80%. While, in case of Foeniculum vulgare Mill.-defatted fraction preparation, the air-dried aerial part (2 kg) of Foeniculum vulgare Mill. was grinded to fine powder and defatted with n-hexane three times. Then, the lipid fraction was collected and dried with rotary evaporator and the residue was further extracted with 80% alcohol to give defatted alcoholic fraction. Moreover, the air-dried leaves (3 kg) of Camellia sinensis were grinding pulverized to fine powder and extracted in a mixture of water and methanol 80 % for preparation of Camellia sinensis extract. Lastly, four kilograms of dried seeds of Vitis vinifera were grounded to fine powder, then extracted with 80% methanol at room temperature for three times for preparation of Vitis vinifera seed extract. Thereafter, the preclinical toxicological study (acute and chronic toxicological studies) for the selected medicinal plant extracts was conducted on one hundred and sixty eight adult Wistar rats (eighty four male and eighty four female). For acute toxicity study, male and female rats were fasted overnight prior to being given orally a single dose of each one of the selected medicinal plant extracts and fraction starting with the maximum soluble dose Summary and Conclusion 287 of each one until reaching the exact dose which caused no deaths for 14 days. While, in case of chronic toxicity study, fifteen male and fifteen female rats were divided into 3 groups, each of 10 rats (5 males and 5 females) for each one of the selected medicinal plants and were given three different doses for each extract for 75 days. Regarding, Foeniculum vulgare Mill. extract, the high-dose level was 0.18 g/kg b.wt./day, the intermediate dose level was 0.09 g/kg b.wt./day and the low-dose was 0.045 g/kg b.wt./day. While, in case of Foeniculum vulgare Mill.-defatted fraction, the high dose was 0.12 g/kg b.wt/day, the intermediate dose was 0.06 g/kg b.wt/day and the low dose was 0.03 g/kg b.wt/day. For, Camellia sinensis extract, the high dose level was 0.16 g/kg b.wt./day, the intermediate dose level was 0.08 g/kg b.wt./day and the low dose was 0.04 g/kg b.wt./day. Moreover, the high dose was 1.13 g/kg b.wt/day, the intermediate dose was 0.56 g/kg b.wt/day and the low dose was 0.28 g/kg b.wt/day for Vitis vinifera seed extract. On the other hand, the pharmacological study was conducted on two hundred adult female Wistar rats. Non-alcoholic fatty liver disease (NAFLD) was induced experimentally in animals by using high fat diet for 24 weeks and non-alcoholic steatohepatitis disease (NASH) was induced experimentally in animals by using high fat diet for 32 weeks. The animals were classified into twenty main groups (10 rats/group): Group (1): Negative control group which was fed ad-libitum with an isocaloric regular rat chow. Group (2): Untreated NAFLD group. Group (3): NAFLD group treated orally with 45 mg/kg b.wt of Foeniculum vulgare extract daily for 8 weeks.