Cellular senescence determines endothelial cell damage induced by uremia

Area of Science:

• Cardiovascular Science
• Nephrology
• Cell Biology

Background:

• Renal dysfunction and endothelial damage are linked to cardiovascular disease.
• The impact of aging on uremia-induced endothelial injury remains unclear.
• Aging may increase endothelial cell apoptosis via oxidative stress pathways.

Purpose of the Study:

• To investigate if senescence-associated oxidative stress mediates uremia-induced endothelial cell injury.
• To compare the susceptibility of young and aging endothelial cells to uremic insults.

Main Methods:

• Human umbilical vein endothelial cells (HUVEC) and rat aortic endothelial cells were used.
• Cells were exposed to uremic serum or models of renal disease.
• Assays included senescence markers (telomere length, β-gal), reactive oxygen species (ROS), mitochondrial depolarization, caspase 3, apoptosis, and NF-κB activity.
• Vitamin C was employed to assess the role of oxidative stress.

Main Results:

• Uremic serum elevated ROS and NF-κB in both young and aging HUVEC.
• Apoptosis was significantly increased in aging HUVEC exposed to uremic serum compared to young cells.
• Vitamin C mitigated endothelial apoptosis in both HUVEC and the rat model, indicating oxidative stress involvement.
• Vitamin C did not reduce senescence-associated oxidative stress.

Conclusions:

• Senescent endothelial cells exhibit heightened sensitivity to uremia-induced oxidative stress and damage.
• Oxidative stress plays a critical role in uremia-related endothelial injury, particularly in aging individuals.
• Targeting oxidative stress in senescent endothelial cells may offer a therapeutic strategy for vascular complications in chronic kidney disease.