Search

Hepatocyte apoptosis is a crucial factor affecting liver quality in brain-dead donors. The identification of key molecular proteins involved in brain-death (BD)-induced hepatocyte apoptosis may help determine an effective method for improving the quality of livers from brain-dead donors. In this study, we used in vivo and in vitro models to investigate the role of chitinase-3-like protein 1 (CHI3L1) in promoting liver cell apoptosis after BD. Chitin was used to inhibit CHI3L1 in a rat model of BD. Macrophage polarization of THP-1 cells and hypoxia/reoxygenation (H/R) of LO-2 cells were used to mimic BD-induced cell stress in liver. We found that CHI3L1 played a vital role in promoting liver cell apoptosis. Six hours after BD, CHI3L1 expression was significantly upregulated in liver macrophages and was associated with BD-induced M1 polarization of these cells. In liver cells cultured under H/R conditions, recombinant CHI3L1 activated the protease-activated receptor 2 (PAR2)/c-June N-terminal kinase (JNK) apoptotic pathway and aggravated apoptosis. Compared with the control group, chitin particles inhibited the expression of CHI3L1 in the liver of brain dead rats, thereby reducing activation of the hepatocyte surface receptor, PAR2, and its downstream JNK/caspase-3 signaling pathway, ultimately reducing hepatocyte apoptosis. In conclusion, our results indicate that CHI3L1 relies on a PAR2/JNK-mediated mechanism to promote BD-induced hepatocyte apoptosis. • CHI3L1 upregulated in liver macrophages after Brain death (BD). • CHI3L1 upregulation associated with BD-induced M1 polarization. • CHI3L1 activated PAR2/JNK pathway, promotes BD-induced hepatocyte apoptosis. • Chitin inhibits CHI3L1 expression and PAR2/JNK/caspase-3 signaling pathway. • Chitin reduces hepatocyte apoptosis. [ABSTRACT FROM AUTHOR]

Beauvericin is a world-spread mycotoxin isolated from the traditional Chinese medicine, Bombyx batryticatus (BB), which has been widely used to treat various neoplastic diseases. This study investigated the anti-hepatocellular carcinoma (HCC) activity of beauvericin and its potential mechanism. In this study, H22-bearing mice were intraperitoneally injected with 3, 5, 7 mg/kg of beauvericin once per-week over a three-week period. TUNEL staining determined the extent of tumor apoptosis induced by beauvericin. ELISA kits detected the level of IL-2, Perforin, and TNF-α, IFN-γ level in the serum. H22 hepatoma cells were exposed to beauvericin (5, 10, and 20 μmol/L) to investigate the underlying pathway. CCK-8 assay was used to observe the influence of beauvericin on the growth of H22 cells. Flow cytometry was used to detect the cell apoptosis and ROS level. Western blotting was performed to detect apoptotic and PI3K/AKT pathway protein production. The results showed that beauvericin could remarkably inhibit the growth of HCC in mice, combined with elevated TNF-α and IL-2. In vitro , beauvericin significantly promoted the generation of ROS, up-regulated Bax/Bcl-2 ratio and cleaved caspase-9, cleaved caspase-3 levels, down-regulated p-PI3K/PI3K ratio, p-AKT/AKT ratio, promoted the apoptosis of H22 cells, and inhibited the growth of H22 cells. Remarkably, treatment with PI3K/AKT activator (740Y–P and SC79) could prevent beauvericin-induced H22 cell apoptosis. These findings collectively indicate that beauvericin inhibits HCC growth by inducing apoptosis via the PI3K/AKT pathway. [Display omitted] • Beauvericin is a world-spread mycotoxin isolated from the traditional Chinese medicine, Bombyx batryticatus (BB). • Beauvericin can suppress hepatocellular carcinoma (HCC) development in vivo and in vitro. • Beauvericin inhibits HCC growth by inducing PI3K/AKT-mediated apoptosis. • Beauvericin could be further investigated as a potential cytotoxic natural compound for the treatment of HCC. [ABSTRACT FROM AUTHOR]