Involvement of Endoplasmic Reticulum Stress in Uremic Cardiomyopathy: Protective Effects of Tauroursodeoxycholic Acid

Area of Science:

• Cardiovascular Biology
• Nephrology
• Cellular Stress Response

Background:

• Uremic cardiomyopathy (UCM) is a significant complication of chronic kidney disease (CKD).
• The role of endoplasmic reticulum stress (ERS) in UCM pathogenesis remains incompletely understood.
• Investigating potential therapeutic interventions for UCM is crucial.

Purpose of the Study:

• To determine the involvement of endoplasmic reticulum stress (ERS) in the development of uremic cardiomyopathy (UCM).
• To evaluate the efficacy of tauroursodeoxycholic acid (TUDCA) as a preventative agent against UCM.

Main Methods:

• A 5/6 nephrectomy (Nx) mouse model was used, with groups receiving saline or TUDCA treatment.
• Renal function, cardiac fibrosis, apoptosis, and cardiac function were assessed.
• ERS markers and fibrotic factors were quantified using molecular biology techniques.

Main Results:

• Nephrectomized mice exhibited impaired renal function, cardiac dysfunction, cardiomyocyte apoptosis, and cardiac fibrosis.
• Elevated ERS markers (GRP78, GRP94, P-PERK, P-eIF2a) and apoptosis pathways (CHOP, caspase-12) were observed in Nx mice.
• TUDCA treatment significantly improved renal and cardiac function and reduced ERS and apoptosis markers.

Conclusions:

• Endoplasmic reticulum stress (ERS) plays a critical role in the pathogenesis of uremic cardiomyopathy (UCM).
• Tauroursodeoxycholic acid (TUDCA) demonstrates cardioprotective effects in UCM.
• TUDCA's benefits are attributed to the inhibition of ERS-induced apoptosis via the CHOP and caspase-12 pathways.