RESUMO
This study investigated the effect of puerarin on human umbilical vein endothelial cells (HUVEC) injured with hydrogen peroxide (H2O2). HUVEC were divided into three groups: a control group, a model group (H2O2 400 μmol·L-1) and a puerarin-treated group (3, 10, 30 and 100 μmol·L-1). HUVEC were cultured with varied concentration of puerarin for 2 h and treated with H2O2 for another 24 h. Cell proliferation was detected by a CCK-8 assay. The mitochondrial membrane potential was measured by a JC-1 fluorescent probe. A transwell chamber assay was adopted to observe cell migration ability. Mitochondrial respiratory function was measured in a two-chamber titration injection respirometer (Oxygraph-2k). The expression of interleukin-1β (IL-1β), interleukin-18 (IL-18) and tumor necrosis factor-α (TNF-α) was detected by quantitative real-time PCR. The expression of pyroptosis-mediated proteins, including cleaved-cysteinyl aspartate-specific proteinase-1 (caspase-1), N-gasdermin D (N-GSDMD), NOD-like receptor protein 3 (NLRP3) and purinergic ligand-gated ion channel 7 receptor (P2X7R) was detected by Western blot. The results show that 400 μmol·L-1 H2O2 treatment for 24 h causes obvious damage to HUVEC. Compared with the model group, puerarin protected against cellular injury in a dose-dependent manner, with the greatest effect at a dose of 30 and 100 μmol·L-1. Puerarin significantly decreased the mitochondrial membrane potential and improved mitochondrial function. Puerarin inhibited cell migration induced by H2O2, suppressed the expression of IL-1β, IL-18 and TNF-α, and down-regulated the pyroptosis-mediated protein. These changes are statistically significant (P < 0.05). These findings demonstrate that puerarin has a protective effect against H2O2-induced oxidative damage of HUVEC by inhibiting the migration of HUVEC cells. The mechanism may be related to improved mitochondrial respiratory function and inhibition of pyroptosis.
RESUMO
This study was to investigate the protective effects of puerarin on myocardial ischemia/reperfusion (MI/R) injury and the underlying mechanism. The MI/R-model was established by ligating the left anterior descending artery (LAD) for 60 min followed by 24 h reperfusion, puerarin (10, 30, and 100 mg·kg-1) was orally administered 20 min before reperfusion. Cardiac function, myocardial infarct index, cardiac damage markers, inflammatory cytokines, and apoptosis index were measured to evaluate the protective effects of puerarin on MI/R injury. The activation of Nod-like receptor protein 3 (NLRP3) inflammasome and Toll like receptor 4 (TLR4)/myeloid differentiation factor 88 (Myd88)/nuclear factor kappa B (NF-κB) pathway were determined by Western blot. All animal experimental procedures were approved by the ethics committee of the Institute of Materia Medica, Peking Union Medical College, Chinese Academy of Medical Sciences. The results showed that puerarin could significantly improve cardiac function, reduce myocardial infarct size, decease the levels of lactic dehydrogenase (LDH), aspartate transaminase (AST), creatine kinase-MB (CK-MB), and cardiac troponin T (cTnT) and suppress cardiomyocyte apoptosis. Meanwhile, puerarin could notably decrease the levels of inflammatory cytokines such as interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α). Western blot analysis revealed that puerarin could downregulate the expression of TLR4, Myd88, NLRP3, apoptosis-associated speck-like protein containing a CARD (ASC), cleaved-caspase 1, cleaved-gasdermin-D (GSDMD), IL-1β, and IL-18, as well as the phosphorylation levels of inhibitor of NF-κB α (IκBα), IκB kinase β (IKKβ), and NF-κB. These findings demonstrated that puerarin could alleviate MI/R injury by suppressing NLRP3 inflammasome activation, possibly via TLR4/Myd88/NF-κB pathway.