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1.
Endocr J ; 57(3): 201-9, 2010.
Article in English | MEDLINE | ID: mdl-20057162

ABSTRACT

Although hyperandrogenism is an important condition and is considered the possible pathogenesis behind polycystic ovary syndrome (PCOS), data supporting this is still scarce. We sought to determine whether or not prenatal androgen exposure leads to PCOS and the possible cellular mechanisms involved. To induce prenatal androgen exposure, pregnant rats were treated with daily subcutaneous injections of free testosterone (T) or dihydrotestosterone (DHT) from embryonic days 16 to 19, and their female offspring were studied as adults. The mRNA expression of the progesterone receptor (PR) in the preoptic area (POA) hypothalamus was higher in the experimental groups than in the control group after ovariectomy and stimulation with estradiol benzoate. The levels of T, P, leutinizing hormone (LH), and estradiol were higher in the experimental groups than in the control groups. The frequency and magnitude of LH secretion was increased in experimental rats as compared with the control group. The anogenital distance of the experimental groups was prolonged and the nipple number was lower than that of the control group. Almost all experimental rats had prolonged or irregular estrous cycles. The experimental groups had fewer corpus luteum and preovulatory follicles and more preantral follicles and antral follicles than the controls. Our findings are consistent with the hypothesis that excess androgen during the prenatal period may cause PCOS. Additionally, we show that hyperandrogenic interference in the release of preovulatory LH surges is mediated by the suppressive effects of androgens on PR expression in POA-hypothalamic tissue.


Subject(s)
Androgens/pharmacology , Dihydrotestosterone/pharmacology , Polycystic Ovary Syndrome/physiopathology , Animals , Disease Models, Animal , Estrous Cycle/drug effects , Female , Hypothalamus/metabolism , Luteinizing Hormone/metabolism , Nipples/abnormalities , Nipples/drug effects , Ovarian Follicle/drug effects , Polycystic Ovary Syndrome/etiology , Polycystic Ovary Syndrome/genetics , Pregnancy , Prenatal Exposure Delayed Effects , Preoptic Area/metabolism , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Receptors, Progesterone/metabolism , Testosterone/blood , Testosterone/pharmacology
2.
Zhonghua Yi Xue Za Zhi ; 87(45): 3174-7, 2007 Dec 04.
Article in Chinese | MEDLINE | ID: mdl-18399108

ABSTRACT

OBJECTIVE: To evaluate the protective effects of oxidative DNA damage by adding antioxidants: ascorbate, catalase (CAT), and superoxide dismutase (SOD) in human semen samples undergoing cryopreservation procedure. METHODS: Semen sample form 30 fertile men were mixed with modified cryoprotectant and divided into six groups according to the category and concentration of antioxidants: ascorbate 300 micromol/L, ascorbate 600 micromol/L, CAT 200 U/ml, CAT 400 U/ml, SOD 200 U/ml, and SOD 400 U/ml. Comet assay was conducted to measure the percentage of comet cells, and the nuclear DNA damaged parameters: tail DNA percentage (TD%) and Olive tail moment (OTM). Flow cytometry was used to detect the reactive oxidative species (ROS). The motility (a + b grade), viable recovery rate, nuclear DNA integrity and reactive oxidative species (ROS) of all groups were analyzed before and/or after freeze-thawing. RESULTS: (After cryopreservation, compared with the control group, the a + b grade sperm rates of the ascorbate 300 micromol/L, CAT 200 U, and CAT 400 U groups were all higher than that of the control group (all P < 0.05), however, the levels of reactive oxygen species (ROS) of the ascorbate 300 micromol/L, CAT 200 U, and CAT 400 U groups were 30 +/- 13, 30 +/- 11, and 30 +/- 11 respectively, all significantly lower than that of the control group (37 +/- 17 , all P < 0.05). The viable recovery rates of the ascorbate 300 micromol/L , CAT 200 U, and CAT 400 U groups were 67% +/- 14%, 68% +/- 14%, and 69% -/+ 15% respectively, all significantly higher than that of the control group (59% +/- 10%, all P < 0.05). (2) The TD% levels of the ascorbate 300 micromol/L, CAT 200 U, and CAT 400 U groups were 41% +/- 4%, 40% +/- 7%, 40% +/- 6%, all similar to that of the raw semen (all P > 0.05), but significantly lower than that of the control group (46% +/- 6%, all P < 0.01). The OTM levels of the ascorbate 300 micromol/ L, CAT 200 U, and CAT 400 U groups were 7.7 +/- 1.2, 7.5 +/- 1.6, and 7.8 +/- 1.9, all similar to that of the raw semen (all P > 0.05), but significantly lower than that of the control group (10.1 +/- 3.1, all P < 0.01) too. The TD% and OTM levels of the other groups were all significantly higher than that of the raw semen (all P < 0.01), but not significantly different from those of the control group (all P > 0.05). (3) ROS was significantly negatively correlated with the motility in all groups (P < 0.05 or P < 0.01). Apart from the ascorbate 600 micromol/L group, the TD% and OTM of the other groups were all significantly positively correlated with the ROS (P < 0.05 or P < 0.01). CONCLUSION: Supplementation of ascorbate or CAT reduces the level of ROS that induces sperm nuclear DNA damage, and improves the human sperm quality in the process of freeze-thawing.


Subject(s)
Antioxidants/pharmacology , DNA Damage/drug effects , Semen Preservation/methods , Semen/drug effects , Adult , Ascorbic Acid/pharmacology , Catalase/pharmacology , Humans , Male , Oxidative Stress/drug effects , Reactive Oxygen Species/metabolism , Semen/metabolism , Superoxide Dismutase/pharmacology
3.
Asian J Androl ; 5(1): 69-72, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12647007

ABSTRACT

AIM: To evaluate the effect of intracytoplasmic sperm injection (ICSI) in the management of cases with a history of conventional in vitro fertilization (IVF) failure. METHODS: Two groups of patients, 19 with normal semen parameters and a history of IVF failure (metaphase II oocytes: 0-30 %) and 28 with severe male factor infertility received ICSI technology during the same period. Ovarian stimulation was achieved by conventional procedure. Transvaginal ultrasound-guided oocyte collection was done 35-37 h after human chorionic gonadotrophin (hCG) injection. Only metaphase II oocytes were selected for microinjection. RESULTS: Fertilization was achieved with ICSI in all the patients. The fertilization rate (75.6 % +/-21.1 % vs. 73.9 % +/-19.2 %), cleavage rate (85.1 % +/-19.3 % vs. 82.7 % +/-22.1 %), clinical pregnancy rate per embryo transfer cycle (31.6 % vs. 28.6 %) and implantation rate per embryo (15.3 % vs. 14.4 %) did not differ significantly between the two groups. CONCLUSION: ICSI is a valuable method for couples with a history of IVF failure. These patients may have a similar ICSI result as in severe male infertility.


Subject(s)
Infertility, Male/therapy , Pregnancy Rate , Sperm Injections, Intracytoplasmic , Abortion, Spontaneous , Adult , Female , Fertilization in Vitro/methods , Humans , Male , Oocytes , Pregnancy , Pregnancy, Ectopic , Spermatozoa , Treatment Failure
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