Suppression of LMCD1 ameliorates renal fibrosis by blocking the activation of ERK pathway

Area of Science:

• Nephrology
• Molecular Biology
• Pathology

Background:

• Tubulointerstitial fibrosis is a key driver of chronic kidney disease (CKD) progression.
• The role of LMCD1 (LIM and cysteine-rich domain-containing protein 1) in renal fibrosis remains unclear, despite its known involvement in cardiac fibrosis.

Purpose of the Study:

• To investigate the role of LMCD1 in the pathogenesis of renal interstitial fibrosis.
• To explore the underlying molecular mechanisms, particularly the involvement of ERK signaling.

Main Methods:

• Utilized a mouse model of unilateral ureteral obstruction (UUO) to induce kidney fibrosis.
• Employed human proximal tubular epithelial (HK-2) cells stimulated with transforming growth factor-β1 (TGF-β1) in vitro.
• Assessed LMCD1 expression, fibrotic markers (fibronectin, collagen I, collagen III), apoptosis, and ERK signaling pathway activation.
• Investigated the effects of LMCD1 knockdown and ERK pathway modulation.

Main Results:

• LMCD1 expression was significantly upregulated in kidney tissues of CKD patients, UUO mice, and TGF-β1-treated HK-2 cells.
• Knockdown of LMCD1 mitigated UUO-induced renal histopathological changes and interstitial fibrosis.
• LMCD1 silencing reduced fibrotic markers, suppressed kidney cell apoptosis, and inhibited ERK signaling activation in UUO mice.
• In vitro, LMCD1 knockdown abrogated TGF-β1-mediated fibrotic gene upregulation and confirmed LMCD1's function via ERK signaling activation.

Conclusions:

• LMCD1 plays a crucial role in promoting renal interstitial fibrosis.
• Inhibition of LMCD1 protects against kidney fibrosis by impeding ERK signaling activation.
• Targeting LMCD1 represents a potential therapeutic strategy for managing chronic kidney disease progression.