| 【Background】Nephrolithiasis,also known as kidney stone,is one of the most common diseases of the urinary system.The main component of renal stones in more than 80% of patients is calcium oxalate(CaOx)with calcium oxalate monohydrate(COM)representing the major form.Numerous studies have shown that calcium oxalate stone formation is an inflammatory process.The CaOx crystals in the kidney interstitium are always surrounded by numerous macrophages in specimens from stone patients and in animal models.Monocyte chemotactic protein 1(MCP-1)is one of the well-accepted and most important inflammatory factors in kidney stones.As a potent monocyte attractant,MCP-1 has been reported to account for nearly 70-80% of the monocyte chemotactic activity in various types of renal inflammation.Monocytes are chemotactically attracted and converge to inflammatory sites where they are activated by COM and inflammatory factors and then secrete additional proinflammatory cytokines that attract more inflammatory cells,thereby aggravating the kidney damage via an amplification loop.Consequently,MCP-1 plays a trigger-point role in the inflammatory cascade of calcium oxalate stone formation.Increasing evidence has shown that long noncoding RNAs(lncRNAs),which are members of the noncoding RNA family with a length exceeding 200 nucleotides,are involved in various cancerous and noncancerous diseases.In a previous study,using a microarray technique and BLAST algorithm,we identified 15 lncRNA homologs in mice and humans with aberrant expression in glyoxylate-induced calcium oxalate stone mouse kidneys and demonstrated that lncRNA CHCHD4P4 promoted epithelial-mesenchymal transition(EMT)in CaOx nephrolithiasis.However,its biological function in calcium oxalate crystal-induced renal injury remains poorly defined.【Objective】To explore the biological function and underlying mechanism of lncRNA HOXA11-AS in the process of calcium oxalate stone formation,providing theoretical basis and therapeutic target for the prevention and treatment of calcium oxalate nephrolithiasis.【Methods】1.The calcium oxalate stone model was established by continuous intraperitoneal injection of glyoxylic acid in vivo,and HK-2 cells exposed to COM in vitro.qRT-PCR was used to measure the expression level of HOXA11-AS in these two models.2.Lentivirus was used to construct stable overexpression or knockdown of HOXA11-AS HK-2 cell lines.The biological function of HOXA11-AS was determined by CCK-8,apoptosis and LDH activity assay.3.The molecular mechanism of HOXA11-AS in calcium oxalate stone formation was investigated by bioinformatics,double luciferase report experiment and rescue experiments.【Results】1.HOXA11-AS was significantly upregulated in CaOx nephrolithiasis both in vivo and in vitro.2.HOXA11-AS overexpression inhibited cell proliferation,promoted apoptosis,and aggravated cellular damage in HK-2 cells exposed to COM,while HOXA11-AS knockdown promoted proliferation,inhibited apoptosis,and attenuated cellular injury.3.Based on four previous microarray reporters and gain-/loss-of-function studies,we demonstrated that HOXA11-AS regulated MCP-1 expression in HK-2.4.The online bioinformatics analysis and dual-luciferase reporter assay results showed that miR-124-3p directly bound to HOXA11-AS and the 3’UTR of MCP-1.5.Rrescue experiment results revealed that HOXA11-AS functioned as a competing endogenous RNA(ceRNA)to regulate MCP-1 expression through sponging miR-124-3p6.Overexpression of miR-124-3p restored the inhibitory effect of proliferation,promotion effects of apoptosis and cell damage induced by HOXA11-AS overexpression.【Conclusions】1.HOXA11-AS inhibited cell proliferation,promoted apoptosis,and aggravated cellular damage in HK-2 cells exposed to COM by sponging miR-124-3p.2.HOXA11-AS mediated CaOx crystal-induced renal inflammation via the miR124-3p/MCP-1 axis. |
