Quercetin Improves Lipopolysaccharide-Induced Septic Liver Injury by Inhibiting the Activation of ROCK/NF-κB/NLRP3 Pathway

Abstract

Quercetin (QUE) is a common flavonoid compound, found in fruits and vegetables, with powerful anti-inflammatory and antioxidant properties. Nevertheless, the protective function and mechanisms of QUE in septic liver injury (SLI) caused by lipopolysaccharide (LPS) are still unknown. This study aimed to investigate the effect of QUE on SLI rats and the underlying mechanisms. Forty male Sprague–Dawley (SD) rats were randomly assigned into four groups (n = 10 per group): control group (CON), control + QUE group (CON + QUE), LPS group (LPS), and LPS + QUE group (LPS + QUE). Rats were administered intragastrically with QUE or normal saline for one week, and LPS was administered on the last day to induce the sepsis model. The results showed that QUE reduced aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities in SLI rats (both p < 0.05). Additionally, histopathological analysis demonstrated that QUE alleviated the liver lesions in SLI rats. Furthermore, QUE also improved the oxidative stress and inflammatory responses, showing the decrease of malonaldehyde (MDA), tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-18, and IL-6 and the increase of superoxide dismutase (SOD) in SLI rats (all p < 0.05). In addition, QUE decreased the expression of Toll-like receptor 4 (TLR4), phosphorylated myosin phosphatase target subunit (p-MYPT)-1, phosphorylated nuclear factor kappa-B (p-NF-κB), NOD-like receptor family pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein (ASC), caspase-1, and cleaved-caspase-1 in liver (all p < 0.05). These results suggested that QUE could be able to treat SLI partly via stimulating the ROCK/NLRP3 pathway.