Melatonin alleviates intrarenal CaOx crystals deposition through inhibiting LPS-induced non-canonical inflammasome-mediated renal tubular epithelial cells pyroptosis

Kai Yao; Zhi-Hui Zhang; Ming-Dong Liu; Feng-Wen Niu; Xi Li; De-Mao Ding; Da-Ming Wang; De-Xin Yu; De-Xiang Xu; Dong-Dong Xie

doi:10.1016/j.intimp.2023.110796

Melatonin alleviates intrarenal CaOx crystals deposition through inhibiting LPS-induced non-canonical inflammasome-mediated renal tubular epithelial cells pyroptosis

Int Immunopharmacol. 2023 Nov;124(Pt A):110796. doi: 10.1016/j.intimp.2023.110796. Epub 2023 Aug 24.

Authors

Affiliations

¹ Department of Urology, The Second Affiliated Hospital of Anhui Medical University, Hefei 230601, China.
² Department of Toxicology, Anhui Medical University, Hefei 230032, China. Electronic address: xudex@126.com.
³ Department of Urology, The Second Affiliated Hospital of Anhui Medical University, Hefei 230601, China; Department of Urology, Fuyang Hospital of Anhui Medical University, Fuyang 236000, China. Electronic address: xiedd_urology@163.com.

PMID: 37633237
DOI: 10.1016/j.intimp.2023.110796

Abstract

Urinary tract infection has long been considered a complication rather than etiology of calcium oxalate (CaOx) nephrolithiasis. This study aimed to explore the role of lipopolysaccharide (LPS), an important component of Gram-negative bacteria, on CaOx nephrolithiasis formation and antagonistic effect of melatonin. Male C57BL/6 mice were intraperitoneally injected with glyoxylate acid (80 mg/kg) daily for 7 days to construct CaOx nephrolithiasis model. A single dose of LPS (2.0 mg/kg) was given 2 h before the second glyoxylate acid treatment in the presence or absence of melatonin (25 mg/kg). Our results found that LPS promoted adhesion of CaOx crystals to renal tubular epithelial cells (RTECs) and intrarenal CaOx crystals deposition. Protein levels of cleaved Caspase-11, N-terminal of cleaved GSDMD (GSDMD-N), NOD-like receptor thermal protein domain associated protein 3 (NLRP3) and cleaved Caspase-1, several markers of non-classical inflammasome activation were upregulated in LPS-treated mouse kidneys and HK-2 cells. Moreover, the number of GSDMD pores was increased in LPS-treated HK-2 cell membrane. Melatonin inhibited Caspase-11 cleavage and antagonized the subsequent LPS-mediated upregulation of GSDMD-N, NLRP3 and cleaved Caspase-1 in kidney tissues and HK-2 cells. In addition, melatonin reduced membrane localization of GSDMD-N and the number of GSDMD pores in LPS-treated HK-2 cells. Accordingly, melatonin inhibited LPS-induced IL-1β and IL-18 in mouse serum and HK-2 culture supernatant. Importantly, melatonin alleviated LPS-induced crystal-cell interactions and intrarenal CaOx crystals deposition. We provide experimental evidence that LPS promoted CaOx nephrolithiasis formation by inducing non-canonical inflammasome-mediated RTECs pyroptosis. Melatonin alleviated CaOx nephrolithiasis formation through inhibiting LPS-induced non-canonical inflammasome-mediated RTECs pyroptosis.

Keywords: Calcium oxalate nephrolithiasis; Lipopolysaccharide; Melatonin; Non-canonical inflammasome; Pyroptosis.