Is the effect of melatonin on vascular endothelial growth factor receptor-2 associated with angiogenesis in the rat ovary?

Abstract

OBJECTIVES Vascular endothelial growth factor (VEGF) and its receptors play important roles in angiogenesis. Melatonin plays an important role in gonadal development; thus, its effect on the reproductive system is evident. We investigated the influence of melatonin on the expression of VEGF, vascular endothelial growth factor receptor-1 (VEGFR1) and vascular endothelial growth factor receptor-2 (VEGFR2), as well as on changes in oxidative stress markers and follicle numbers in rat ovaries. METHODS For this purpose, 45 Wistar rats were separated into the following groups: Group 1, control; Group 2, vehicle; and Group 3, melatonin. Rats in Group 3 were treated with melatonin at 50 mg/kg/day for 30 days. The effects of melatonin on the expression of VEGF, VEGFR1 and VEGFR2 were established by immunohistochemistry analysis. The effects of melatonin on antioxidant enzyme activities were demonstrated by spectrophotometric analysis. RESULTS Based on immunohistochemistry analysis, VEGFR2 was predominantly localized to theca cells in the ovary. Our data indicate that melatonin treatment can significantly increase VEGF and VEGFR1 expression in the ovary ( p <0.05). Additionally, the number of degenerated follicles significantly decreased with melatonin treatment ( p <0.05). Melatonin administration also led to significant increases in antioxidant enzyme levels in the ovary. CONCLUSION Melatonin treatment exerts protective effects on follicles against increased lipid peroxidation through modulating tissue antioxidant enzyme levels. These effects may be related to angiogenesis and antioxidant activities.

Melatonin, Its Beneficial Effects on Embryogenesis from Mitigating Oxidative Stress to Regulating Gene Expression

“…The relevance of such immune cell dampening in conjunction with its embryonic effects will be interesting to determine. It is also important to note that many of MT effects can be mediated via the alpha 7 nicotinic acetylcholine receptor (α7nAChR), which is also a powerful immune regulator, modulator of embryo development [ 24 ], and is expressed on mitochondria where it acts to regulate Ca2+ influx [ 25 ]. α7 receptors are also involved in angiogenic and neurogenic activity, and have anti-apoptotic effects.…”

Melatonin Alleviates Oxidative Stress Induced by H2O2 in Porcine Trophectoderm Cells

“…On the one hand, MT protects the body from the harmful effects of free radical damage [ 15 , 16 ]. On the other hand, MT alleviates oxidative stress and protects the ovaries from oxidative damage by elevating antioxidant enzyme activity [ 17 , 18 ]. The antioxidant effects of MT can protect cells from the damage of oxidative stress damage [ 19 , 20 ].…”