Fortunellin protects against high fructose-induced diabetic heart injury in mice by suppressing inflammation and oxidative stress via AMPK/Nrf-2 pathway regulation.

Inflammation and oxidative stress contribute to the progression of diabetic cardiomyopathy (DCM). The study was first designed to calculate the role of an anti-inflammatory and anti-oxidant Fortunellin (For) in high fructose-induced cardiac injury in diabetic mice. Fortunellin was found to be none of toxicity to mice and cells using various assays. High fructose was used to induce mice with diabetes. The heart histopathological changes and cardiac function were measured. Fortunellin significantly attenuated the score of histopathological alterations and alleviated heart function, accompanied with reduced inflammation and oxidative stress. The pro-inflammatory cytokines and the expression of p-IκB kinase α (IKKα), p-IκBα, and p-nuclear factor-κB (NF-κB) were dramatically reduced by Fortunellin, while superoxide dismutase (SOD), catalase (CAT), heme oxygenase-1 (HO-1) and p-AMP-activated protein kinase (AMPK) were significantly enhanced. Moreover, in H9C2 cells with nuclear factor erythroid 2-related factor 2 (Nrf2) knock-down abolished the prevention of Fortunellin against cardiac injury, proved by elevated inflammatory response and oxidative stress. Suppression of p-AMPK reduced the level of Nrf2 and HO-1 induced by Fortunellin, eliminating the protective role of Fortunellin. For the first time, our study suggested that Fortunellin protected against fructose-induced inflammation and oxidative stress by enhancing AMPK/Nrf2 pathway in diabetic mice and cardiomyocytes with fructose treatment.