Leptin Accelerates Endothelial Wound Healing: Role of Endothelial Nitric Oxide Synthase Expression.

Background: The endothelium is crucial for the control of vascular homeostasis and plays a role in angiogenesis. Leptin, a protein released mainly by adipose tissue, plays a key role in the regulation of energy balance and angiogenesis. We aimed to investigate the changes of endothelial nitric oxide synthetase expression on human umbilical vein endo- thelial cells wound healing model after leptin treatment.

Methods: In this study, 5 groups were planned as Group 1: control (untreated), Group 2: treated with 0.1 ng/mL leptin, Group 3: treated with 1 ng/mL leptin, Group 4: treated with 10 ng/mL leptin, and Group 5: treated with 100 ng/mL leptin. Closure rates of wound areas were calculated by the Image J program after 24 hours of leptin treatment. The WST-1 assay was used to calculate the cell viability. Immunocytochemical analysis was performed for endothelial nitric oxide synthase expression and H-Score was calculated.

Results: The closure rates of wound areas were calculated as 80.24%, 89.73%, 87.40%, 90.73%, and 93.70%, respectively. When all groups treated with leptin were comparedwith the control group, there was a statistically significant difference (P < .05). The WST-1 results showed that the most increasing levels of viable cells were found in the groups treated with 0.1 ng/mL leptin and 100 ng/mL leptin when compared to the control group. H-Score values of each group were calculated as 284.8 ± 15.22, 288.6 ± 8.41, 291 ± 8.16, 295.2 ± 11.60, and 308.8 ± 4.32, respectively. The difference between the control group and the group treated with 100 ng/mL leptin was statistically significant (P < .05).

Conclusions: Endothelial nitric oxide synthase expression in human umbilical vein endo- thelial cells increased depending on the leptin dose and the highest increase was in the group treated with 100 ng/mL leptin.