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Highlights: [•] VHL up-regulates SOD2 expression on mRNA and protein levels. [•] HIF-1α contributes to the transcriptional suppression of SOD2 expression in the pVHL deficient cells. [•] HIF-1α directly binds the hypoxia-responsive element of SOD2 promoter. [•] The expression of HIF-1α negatively correlates with SOD2 expression in pVHL deficient renal clear cell carcinoma tissues. [ABSTRACT FROM AUTHOR]

NLRP3 inflammasome activation plays an important role in the development of pancreatic fibrosis. However, it is unclear whether the activation of the NLRP3 inflammasome is directly involved in the activation of Pancreatic stellate cells (PSCs). The aim of this study was to investigate the role and mechanism of the NLRP3 inflammasome in the activation of PSCs. In vivo, a rat model of chronic pancreatitis (CP) was induced by intravenous injection of dibutyltin dichloride (DBTC). In vitro, rat primary PSCs were isolated from pancreatic tissues and incubated with the NLRP3 inflammasome activator LPS, the NLRP3 inhibitor MCC950, or NLRP3 siRNA. The results showed that the expression of NLRP3, pro-Caspase-1, Caspase-1 and IL-18 was increased in the rat model of CP and during PSCs activation. LPS increased the protein levels of NLRP3, ASC, Caspase-1, IL-1β and IL-18 accompanied by the upregulation of α-SMA, Col I and FN expression. Moreover, MCC950 or NLPR3 siRNA decreased the expression of α-SMA, Col I, FN, TGF-β1 and p-Smad3. Furthermore, MCC950 reversed the LPS-induced upregulation of α-SMA, FN and Col Ⅰ expression in PSCs. This study revealed that the NLRP3 inflammasome is directly involved in the activation of PSCs in vivo and in vitro. Inhibiting NLRP3 suppresses the activation of PSCs through the TGF-β1/Smad3 pathway. Proposed role of NLRP3 inflammasome activation involved in PSCs activation. The current study applied LPS stimulation to show the involvement of NLRP3 inflammasome pathway in the secretion of IL-1β and IL-18 from PSCs contributed to the activation and ECM deposition by TGF-β1-Smad3 pathway, suggesting that blockage of the NLRP3 inflammasome axis represents a potential therapeutic approach to pancreatic fibrosis. [Display omitted] • NLRP3 inflammasome was activated with the extension of activation time of PSCs. • LPS triggered PSCs activation through activating NLRP3 Inflammasome. • Inhibition of NLRP3 inflammasome mitigates the activation of PSCs. • NLRP3 inflammasome activates the TGF-β1/Smad3 signaling pathway in PSCs. [ABSTRACT FROM AUTHOR]