Background: Pyroptosis is a form of programmed cell death mediated by inflammatory responses.This research aimed to study the potential mechanism of pyroptosis pathway played in promoting diabetic kidney disease (DKD) progression, and to investigate Canagliflozin(CANA), a sodium glucose cotransporter-2 (SGLT2) inhibitor, protect kidneys by inhibiting the activation of pyroptosis pathway. This research can provide new ideas for the prevention and treatment of DKD.

Methods: Human tubular (HK-2) cells were cultured in DMEM medium and were divided into normal control group (NC group), high glucose group (HG group), high glucose with CANA group, bovine serum albumin group(BSA group), BSA with CANA group. After 24 hours of culture, qPCR, Western blotting and ELISA were used to detect the activation, expression and secretion of classic NLRP3/Caspase(Casp)-1/Gasdermin D (GSDMD) pyroptosis pathway, including NLRP3, Casp-1, interleukin (IL)-1β, IL-18 and GSDMD,etc. Detect the expression of NKAIN4, a Na+-K+-ATP enzyme-acting protein. LDH release test and Light microscopy was used to analyze cell death and rupture of the cell membrane.

Results: Compared with NC group, in HG group and BSA group, the amount of dead HK-2 cells is higher, the expression levels of NLRP3, Casp-1, IL-1 β, IL-18, GSDMD and NKAIN4 were significantly up-regulated, the concentration of IL-1 β, IL-18 and LDH in the cultured medium were elevated. When using Canagliflozin, these data mentioned above were suppressed compared with HG group and BSA group .

Conclusions: 1. Pyroptotic cell death of HK-2 cells induced by HG and BSA may promotes DKD progression, renal function deterioration, and inflammation. 2. SGLT2 inhibitor Canagliflozin can attenuate inflammatory response by inhibiting GSDMD-related pyroptosis in DKD. This may because CANA attenuate the activation of Na+-K+-ATP enzyme, transport of K+ and activation of NLRP3. Its specific mechanism and animal experiments are being further studied.

Disclosure

S. Ren: None. Y. Xue: None.

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