Assessment of vascular endothelial growth factor expression and apoptosis in the ovarian graft: can exogenous gonadotropin promote angiogenesis after ovarian transplantation?
OBJECTIVE
To evaluate the effects of gonadotropin on angiogenesis by assessing vascular endothelial growth factor (VEGF) expression in rat ovaries transplanted after freezing and thawing.


METHODS
In vitro laboratory experiments.


METHODS
Academic research institute.


METHODS
Sixty immature female rats.


METHODS
Frozen-thawed ovaries were autotransplanted into the SC tissue of 60 rats (ages between 21 and 28 days). After transplantation, either pregnant mare's serum gonadotropin (PMSG) or saline was administered. The grafted ovaries were collected 2, 7, and 30 days after transplantation for evaluation.


METHODS
Assessment of the morphology and number of follicles, evaluation of apoptosis, and analysis of VEGF expression in the grafted ovaries.


RESULTS
Most follicles in the grafts were apoptotic on day 2 but recovered by day 7. The proportion of antral follicles and corpora lutea in the graft correlated with the duration after transplantation. A significant increase in the expression of VEGF188 mRNA was noticed in the grafted ovaries on day 2. Moreover, the mRNA expression in the PMSG group was higher than that in the control group. The increased VEGF protein production in the graft was confirmed by Western blot analysis.


CONCLUSIONS
In ovariectomized animals, gonadotropin treatment may not provide any added benefits for folliculogenesis and angiogenesis. Nevertheless, a significant increase in the VEGF188 isoform in the gonadotropin-treated group may suggest the positive effect of exogenous gonadotropin therapy in the early stages of angiogenesis.
Yang
Hyunwon
H
Eulji Life Science Institute, Eulji University School of Medicine, Seoul, South Korea.
Lee
Hyang Heun
HH
Lee
Hoi Chang
HC
Ko
Duck Sung
DS
Kim
S Samuel
SS
D000818:Animals; D017209:Apoptosis; D015925:Cryopreservation; D005260:Female; D015870:Gene Expression; D006062:Gonadotropins / Q000378:metabolism*; D018919:Neovascularization, Physiologic; D010052:Ovariectomy; D010053:Ovary / Q000502:physiology / Q000637:transplantation*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014183:Transplantation, Heterologous; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism*
D006062:Gonadotropins; D042461:Vascular Endothelial Growth Factor A