CatSper in sperm hyperactivation and male infertility: Advances in studies / 中华男科学杂志

The CatSper channel is known as one of the most important Ca²⁺ channels on the cell membrane of mammalian sperm and plays a key role in the motility, hyperactivation and fertilization function of sperm. The CatSper protein, expressed exclusively in the principal piece of the sperm tail, is composed of CatSper1-4 and 5 auxiliary unitsβ,γ,δ and ε, and has an essential part in the functional and structural domains of Ca²⁺as well as in the spatiotemporal regulation of the P-Tyr protein, sperm hyperactivation, efficient sperm migration in the oviduct, egg penetration, and normal fertility. Recent studies show that functional deficiency of CatSper seriously affects sperm function,and the loss of any one of its 9 subunits may lead to male reproductive dysfunction. This paper outlines recent advances in the studies of the CatSperprotein, focusing on its expression, location, structure, and regulation,as well as itsinfluence on sperm hyperactivation and male reproduction.

Modified super-long down-regulation protocol improves fertilization and pregnancy in patients with poor ovarian responses / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The successful end-point of in vitro fertilization (IVF) treatment is for a woman to give live birth. This outcome is based on various factors including adequate number of retrieved eggs. Failure to recruit adequate follicles, from which the eggs are retrieved, is called a "poor response". How to improve the clinical pregnancy rates of poor responders was one of the tough problems for IVF.</p><p><b>METHODS</b>The study involved 51 patients who responded poorly to high dose gonadotropin treatment in their previous cycles at our reproductive center, between April 2010 and February 2012. The previous cycle (group A) received routine long protocol; the subsequent cycle (group B) received modified super-long down-regulation protocol. The primary outcome of the study was the number of oocytes fertilized. The increase in the pregnancy rate was the secondary outcome. Differences between the groups were assessed by using Student's t test and c(2) test where appropriate.</p><p><b>RESULTS</b>The patients' average age was (36.64 ± 3.85) years. The mean duration of ovarian stimulation cycles of the group A patients was longer than those of the group B patients. The total dose of follicle-stimulating hormone (FSH) was significantly lower in the subsequent cycle. The peak value of serum estradiol on human chorionic gonadotrophin (hCG) day was lower in group A as compared with group B. The number of metaphase II oocytes recovered was significantly higher in group B. The cleavage rate in group A was significantly lower than in group B, 49 patients in group B reached embryo transfer stage, while 46 patients in group A reached this stage. Patients in group B received significantly more embryos per transfer as compared with group A. More pregnancies and more clinical pregnancies with fetal heart activity were achieved in group B.</p><p><b>CONCLUSIONS</b>This comparative trial shows that poor responder women undergoing repeated assisted reproduction treatment using modified super-long down-regulation protocol achieve more oocytes, leading to higher fertilization rate, compared to women receiving routine long protocol. Our study also showed that clinical pregnancy rate was significantly improved.</p>