Reduced mtDNA Copy Number Links to Vascular Calcification and Restores After Transplantation

Area of Science:

• Mitochondrial biology
• Vascular biology
• Nephrology

Background:

• Chronic kidney disease (CKD) is associated with accelerated vascular aging, vascular calcification, and increased mortality.
• Declining mitochondrial DNA copy number (mtDNA-cn) is linked to aging, frailty, and mortality in cardiovascular diseases and cancer.
• The role of mtDNA-cn in vascular calcification within the uremic environment is not well understood.

Purpose of the Study:

• To investigate the association between mtDNA-cn and vascular calcification in CKD patients.
• To assess the impact of renal transplantation (RTx) on mtDNA-cn levels.
• To explore mtDNA-cn as a potential biomarker for vascular aging in CKD.

Main Methods:

• Quantitative PCR (qPCR) was used to measure mtDNA-cn in 211 CKD5 patients and 196 healthy controls.
• mtDNA-cn was re-evaluated one year post-RTx in 32 patients.
• Associations with vascular calcification, cell-free mtDNA (ccf-mtDNA), biological age, and cardiovascular disease (CVD) risk were analyzed.

Main Results:

• CKD5 patients exhibited significantly lower mtDNA-cn compared to controls.
• Lower mtDNA-cn correlated with increased biological age, vascular calcification, and CVD risk.
• Male patients showed significant recovery of mtDNA-cn one year after RTx; mtDNA-cn and ccf-mtDNA were inversely correlated.

Conclusions:

• Low mtDNA-cn is associated with vascular aging and calcification in CKD.
• Renal transplantation can restore mtDNA levels, potentially improving vascular health.
• mtDNA may serve as a biomarker and therapeutic target for vascular aging in uremia.