During infancy low levels of follicle-stimulating hormone may result in high rate of germ cell apoptosis.

PURPOSE: It has been suggested that follicle-stimulating hormone (FSH) plays a role in preventing germ cell apoptosis. We aimed to compare apoptotic rate of boys with cryptorchidism having different levels of FSH in order to investigate its role in apoptosis.

METHODS

Hormonal profiles and testicular biopsies from 30 boys with unilateral cryptorchidism (age range: 4-14 months) were included. Based on FSH level, the boys were grouped into three (3 × 10) having high (>97.5percentile), low (<2.5percentile), or within normal range. Sections underwent immunohistochemical staining to analyze the number of germ cells and type A dark spermatogonia per cross-sectional tubule. One section was co-stained with immunofluorescent antibodies against an apoptotic marker (cleaved caspase-3), proliferation marker (Ki67), Sertoli cell marker (anti-Müllerian hormone) and processed by confocal imaging for analysis. Germ cell apoptosis was calculated as the apoptosis index (percentage caspase-3+ germ cells/total germ cell number).

RESULTS

Fifty percent (5/10) of the boys with low FSH had an apoptosis index above 90% compared with 15% (3/20) of the boys with normal or high FSH (p = 0.04). Caspase-3+ germ cells were most likely to be located on the basement membrane (p<0.05).

CONCLUSION

Our findings lead to trends proposing that FSH may play a role in preventing apoptosis.

TYPE OF STUDY: Prognosis Study LEVEL OF EVIDENCE: III.