Assessment of fertility protection and ovarian reserve with GnRH antagonist in rats undergoing chemotherapy with cyclophosphamide

<p>Abstract</p> <p>Background</p> <p>Reproductive function following chemotherapy is of increasing importance given that survival rates are improving. We assessed whether a gonadotropin-releasing hormone antagonist (GnRHant; cetrorelix) could promote ovarian protection against damage due to chemotherapy.</p> <p>Methods</p> <p>Forty-two female Wistar rats were used in this study. Animals were divided into four groups: group I (n = 9) received placebo twice; group II (n = 12) received placebo + cyclophosphamide (CPA); group III (n = 12) received GnRHant + CPA; and group IV (n = 9) received GnRHant + placebo. After medication, the estrous cycle was studied through vaginal smears. Rats were mated, pregnancy was documented and the number of live pups evaluated. Afterwards, rat ovaries were removed and prepared for histological studies. The ovarian cross-sectional area was measured and follicles were counted.</p> <p>Results</p> <p>Cyclic changes in vaginal smears were observed in all but one animal after treatment, but group II had a significantly lower rate of animals with proestrus or estrus (p < 0.01). The offspring was markedly reduced by CPA treatment (group II, 3.00 +/- 1.33 pups vs. group I, 11.44 +/- 0.78 pups, p < 0.01) and this effect was partly reversed by pre-treatment with GnRHant (group III, 7.00 +/- 1.31 pups). The ovarian cross-sectional area was not significantly different between groups, neither was the number of individual follicle types. However, rats in Group IV had a higher total number of ovarian follicles than those in the control group (17.1 +/- 1.22 vs. 10.9 +/- 0.70, p < 0.05).</p> <p>Conclusion</p> <p>The use of a GnRHant before CPA chemotherapy provided protection of fertility.</p

Stem cells: Are they the answer to the puzzling etiology of endometriosis?

Endometriosis is a chronic bening disease characterizaed by the presence of abnormally located tissue resembling the endometrium with glands and stroma. This disease has a high degree of morbidity due to chronic pelvic pain and infertility. The disease is likely to be polygenic and multifactorial, but the exact pathogenic mechanisms are still not entirely clear. Recently, adult stem cells have been identified in several tissues, including the endometrium. These cells are probably involved in the regenerative ability of the endometrial cycle, and also in the pathogenesis of proliferative gynaecological diseases, such as endometriosis. The identification of stem cells in animal and human tissues is very complex and the putative stem cells are supposed to be found through several assays such as clonogenicity, label-retaining cells, “side- population” cells, undifferentiation markers, and cellular differentiation. Bone marrow-derived stem cells transplanted into humans and animals have also been identified in eutopic endometrium and endometriotic implants. This review evaluates the available evidence regarding stem/progenitor cells in the human endometrium and explores the possible involvement of these cells in the etiology of endometriosis