Chinese Herbal Medicine Suyin Detoxification Granule Inhibits Pyroptosis and Epithelial-Mesenchymal Transition by Downregulating MAVS/NLRP3 to Alleviate Renal Injury

Abstract

Purpose: Proteinuria is an independent risk factor of chronic kidney disease (CKD). Albumin-induced tubulointerstitial inflammation and epithelial-mesenchymal transition (EMT) via the activation of NLRP3 inflammasome is a potential therapeutic target for CKD. Suyin Detoxification Granule (SDG) improves proteinuria and postpones renal failure. However, the underlying mechanism is still unknown. Methods: Firstly, the rat model of renal failure was established using intragastric administration of adenine. Renal function, proteinuria, inflammatory indicators in serum, and renal pathology were assessed, and renal immunohistochemical staining of NLRP3 inflammasomes was performed after intervention with low and high concentrations of SDG. Secondly, the model of renal tubular epithelial HK-2 cells was established using albumin in vitro, and the cell viability, EMT phenotype, and the expression of proteins in the NLRP3 inflammasome signaling pathway were measured after the freezedried powder of Suyin Detoxification Prescription (SDP) and CY-09, which is a selective and direct NLRP3 inhibitor, were co-incubated with albumin. ATP, SOD, mitochondrial membrane potential, and ROS were further measured in vitro, and changes in the mitochondrial function after SDP intervention were observed. The mitochondrial antiviral signaling protein (MAVS) was knocked down using siRNA, and the interaction between MAVS and NLRP3 was verified using Western blotting, polymerase chain reaction (PCR), and immunofluorescence. Results: SDG improved renal function and proteinuria, alleviated renal fibrosis, and reduced serum inflammation and the expression of the components of the NLRP3 inflammasome in the kidney. In vitro, SDP and CY-09 enhanced cell viability after injury with albumin and inhibited pyroptosis induced by the NLRP3 inflammatory signaling pathway and expression of proteins involved in EMT. It was further found that SDP alleviated the mitochondrial dysfunction caused by albumin. The knockdown of MAVS reduced the expression of NLRP3 pathway proteins and their mRNA levels and also weakened the co-localization of NLRP3, thus, reducing cell pyroptosis. Conclusion: SDP protected renal tubular epithelial cells from cell pyroptosis and EMT by regulating the albumin-induced mitochondrial dysfunction/ MAVS/ NLRP3-ASC-caspase-1 inflammasome signaling pathway.

Research progress on the activation mechanism of NLRP3 inflammasome in septic cardiomyopathy

“…When mitochondria are destabilized, cardiolipin redistributes to the outer surface of mitochondria and activates NLRP3 inflammasome by directly binding to the LRR structure domain of NLRP3 54 . In addition, the formation of NLRP3 inflammasome assembly requires the involvement of multiple mitochondrial proteins such as mitochondrial antiviral signaling protein (MAVS) and mitochondrial fusion protein 2 (Mfn2) 55,56 . Therefore, the mitochondria not only release the MAVS but also the mitochondrial fusion protein (Mfn2).…”

The Role of Pyroptosis in the Pathogenesis of Kidney Diseases

“…Huoxue Jiedu Huayu formula prevented the development of pyroptosis by downregulating NLRP3/caspase-1/IL-1β pathway in UUO rats [ 102 ]. Suyin Detoxification Granule inhibited NLRP3-mediated pyroptosis during renal fibrosis [ 103 ]. Dapagliflozin, a sodium-glucose cotransporter-2 inhibitor, alleviated renal fibrosis by reducing pyroptosis-related cytokines [ 104 ].…”

“…Besides, MCC950 was substantiated to effectively blunt the pyroptosis of TECs under chronic intermittent hypoxia treatment [ 142 ]. Another selective and direct NLRP3 inhibitor, CY-09, also arrested the progression of renal fibrosis by preventing the activation of the NLRP3/ASC/caspase-1 signaling pathway in HK-2 cells treated BSA [ 103 ].…”

Simultaneous determination of multiple constituents, serum composition, and tissue distribution of Qingshen granule using ultra‐high performance liquid chromatography‐quadrupole‐orbitrap high‐resolution mass spectrometry

“…Current treatments for CKD are limited; thus, many patients seek alternative therapies, such as traditional Chinese medicine (TCM) [6,7]. Several basic and clinical studies have confirmed that TCM protects kidney function and delays CKD progression [8][9][10].…”