TAK1 mediates apoptosis via p38 involve in ischemia-induced renal fibrosis

Area of Science:

• Nephrology
• Molecular Biology
• Pathophysiology

Background:

• Renal fibrosis is a hallmark of chronic kidney disease (CKD), but its molecular underpinnings, especially following ischemia-induced acute kidney injury (AKI), require further elucidation.
• Transforming growth factor-β (TGF-β)-activated kinase 1 (TAK1) is implicated in fibrotic processes, interacting with TGF-β and potentially influencing fibrosis progression.

Purpose of the Study:

• To investigate the specific role of TAK1 in the development of renal fibrosis induced by ischemia.
• To explore the molecular mechanisms, including the TAK1/p38 signaling pathway, involved in ischemia-induced renal fibrosis and apoptosis.

Main Methods:

• Utilized a mouse model of ischemia-induced AKI, administering a TAK1 inhibitor.
• Assessed renal function (serum creatinine), tubular damage, and fibrosis levels.
• Analyzed p38 phosphorylation, apoptosis markers (Bax, caspase 3), and apoptosis in kidney tissues and renal tubular epithelial cells subjected to hypoxia/reoxygenation (H/R) with or without TAK1 manipulation.

Main Results:

• TAK1 inhibition in mice significantly reduced serum creatinine, tubular damage, and fibrosis following ischemia-induced AKI.
• TAK1 inhibition decreased p38 phosphorylation, Bax and caspase 3 expression, and apoptosis in the kidneys.
• TAK1 overexpression in renal tubular epithelial cells exacerbated apoptosis and fibrosis following H/R, a process dependent on the TAK1/p38 signaling pathway.

Conclusions:

• TAK1 plays a critical role in the pathogenesis of ischemia-induced renal fibrosis.
• The TAK1/p38 signaling pathway is implicated in mediating cell apoptosis and fibrosis in the context of ischemia-reperfusion injury.
• Targeting TAK1 presents a potential therapeutic avenue for mitigating renal fibrosis following ischemic events.