Hepatoprotective effects of different mulberry leaf extracts against acute liver injury in rats by alleviating oxidative stress and inflammatory response.

This study investigated the hepatoprotective effects of various mulberry ( Morus alba L.) leaf extracts (MLEs), including mulberry ethanol extract (MEE), aqueous extract (MAE) and a combination extract (MCE) against D-galactosamine (D-GalN)/lipopolysaccharide (LPS)-induced acute liver injury in rats. It aimed to explore the possible molecular mechanism of the liver-protecting function of mulberry leaves and provide a reference for choosing the appropriate extraction method. The results showed that the three extracts contained different amounts of phenolic compounds, 1-deoxynojirimycin (DNJ) and polysaccharides. MLEs markedly improved the pathological status of rat liver tissue, decreased the levels of AST, ALT, TNF-α, IL-1β, IL-6 and MDA, while increased the levels of GSH, SOD and CAT in the D-GalN/LPS-treated rats at the same time. MEE, with the highest amount of total phenolics, exhibited the highest antioxidant activity corresponding to the protein expression level of Nrf2 and HO-1. MCE significantly suppressed the expression of apoptosis-related dot-like protein (ASC) and Caspase-1 and inhibited the phosphorylation of p38 MAPK and ERK1/2, thereby showing high anti-inflammatory activity. These results indicated that the active components from mulberry leaves protected rats against acute liver injury, attributed to a reduction in both oxidative stress and inflammatory response. The protective effect may be implicated in regulating the Nrf2, NLRP3 and MAPK signaling pathways.