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

Abstract

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 endothelial 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 compared with 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 endothelial cells increased depending on the leptin dose and the highest increase was in the group treated with 100 ng/mL leptin.