Papaya improves non-alcoholic fatty liver disease in obese rats by attenuating oxidative stress, inflammation and lipogenic gene expression.

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is a global health issue that is correlated with obesity and oxidative stress.

AIM

To evaluate the anti-NAFLD effect of papaya in high fat diet induced obesity in rats.

METHODS

Four-week-old male Sprague-Dawley rats were divided into four groups after 1 wk of acclimatization: Group 1 was the rats fed a normal diet (C); group 2 was the rats fed a high fat diet (HFD); group 3 was the rats fed a HFD with 0.5 mL of papaya juice/100 g body weight (HFL), and group 4 was the rats fed a HFD with 1 mL of papaya juice/100 g body weight (HFH) for 12 wk. At the end of the treatment, blood and tissue samples were collected for biochemical analyses and histological assessment.

RESULTS

The results of the HFH group showed significantly reduced body weight (HFH HFD, < 0.01), decreased NAFLD score (HFH HFD, < 0.05), and reduced hepatic total cholesterol (HFL HFD, < 0.01; HFH HFD, < 0.001), hepatic triglyceride (HFH HFD, < 0.05), malondialdehyde (HFL, HFH HFD, < 0.001), tumour necrosis factor-α (HFH HFD, < 0.05) and interleukin-6 (HFH HFD, < 0.05) when compared to the HFD group. However, the liver weight showed no significant difference among the groups. The activities of catalase and superoxide dismutase significantly increased in HFH when compared with the HFD group ( < 0.05 and < 0.001, respectively). The suppression of transcriptional factors of hepatic lipogenesis, including sterol regulatory element-binding protein 1c and fatty acid synthase, were observed in the papaya treated group (HFH HFD, < 0.05). These beneficial effects of papaya against HFD-induced NAFLD are through lowering hepatic lipid accumulation, suppressing the lipogenic pathway, improving the balance of antioxidant status, and lowering systemic inflammation.

CONCLUSION

These current results provide experimental-based evidence suggesting papaya is an efficacious medicinal fruit for use in the prevention or treatment of NAFLD.