The Y chromosome contains genes and gene families that play critical roles in the process of testis determination and differentiation. Male infertility can be induced by many factors, and extensive studies have strongly indicated that Y chromosome microdeletions are closely related to male reproductive dysfunction. Because most of the Y chromosome does not participate in sexual recombination, it has degenerated both in size and gene content, in comparison with the X chromosome. Consequently males may be faced with survival problems in the future. This article reviews the role of the Y chromosome in male infertility and the fate of the male in the future.
Chromosomes, Human, Y ; Humans ; Infertility, Male ; genetics ; Male

OBJECTIVETo investigate the effects of prepubertal continuous exposure to dibutyl phthalate (DBP) on the testis development in SD rats.

METHODSTwenty-one-day-old weanling prepubertal male SD rats were randomly divided into a control (n = 24) and an experiment group (n = 54), gavaged daily with corn oil vehicle or corn oil + DBP at the repeated dose of 0 mg/(kg x d) (control), 50 mg/(kg x d) (low-dose), 200 mg/(kg x d) (medium-dose) and 600 mg/(kg x d) (high-dose) for 14, 21 and 28 days, and then sacrificed by decapitation on PND35, PND42 and PND49. The body weight gain, the testis weight and volume and the weight of accessory sex organs were measured, the serum testosterone level assayed by chemoluminescence technique, the testis tissues stained by H&E and observed under the light microscope for morphological alteration, the mean diameter of the seminiferous tubules determined and testicular biopsy scores obtained.

RESULTSDisordered arrangement of spermatogenic cells was found in some seminiferous tubules on PND35 in the low-dose group, but testis development and spermatogenesis were normal on PND42 and PND49. In the medium-dose group, disordered arrangement and decreased number of spermatogenic cells were observed on PND35 and PND42, but without testicular atrophy, and various grades of spermatogenic cells and sperm were seen on PND49. High-dose DBP slowed down the body weight gain, decreased serum T levels and induced degeneration of seminiferous tubules, arrest of spermatogenic epithelium development and necrosis of spermatogenic cells. The pubertal rats (PND49) showed testicular atrophy, azoospermia and delayed development of accessory sex organs.

CONCLUSIONPrepubertal continuous exposure to DBP induces damages to testicular development and spermatogenesis in a dose-dependent manner, and those induced by high-dose DBP cannot be recuperated in the phase of prepubertal development, while the slight adverse effects on the testis induced by low- and medium-dose DBP could be completely or partly reversible before PND49.

Animals ; Dibutyl Phthalate ; toxicity ; Environmental Exposure ; Growth ; drug effects ; Male ; Rats ; Rats, Sprague-Dawley ; Testis ; drug effects ; growth & development

OBJECTIVETo study the clinical efficacy of vardenafil on erectile dysfunction (ED) patients with kidney-yang deficiency, kidney-yin deficiency or liver-qi stasis.

METHODSBased on the syndromes of Traditional Chinese Medicine, 124 ED patients were divided into Groups A (kidney-yang deficiency, n=44), B (kidney-yin deficiency, n=41) and C (liver-qi stasis, n = 39). All the patients were treated with vardenafil at 5 mg daily for 8 weeks, and the therapeutic effects were evaluated by comparing the scores on IIEF-5 and Erection Quality Scale (EQS) before and after the treatment.

RESULTSAfter vardenafil treatment, the IIEF-5 and EQS scores of the ED patients were markedly increased, with statistically significant differences among the three groups (P < 0.01). The success rate of sexual intercourse was significantly improved in Groups A, B (P < 0.01) and C (P < 0.05). And the hardness of penile erection was enhanced by 81.82%, 73.17% and 43.59% respectively in the three groups of patients.

CONCLUSIONVardenafil is more effective for ED patients with kidney-yang or kidney-yin deficiency than for those with liver-qi stasis.

Adult ; Erectile Dysfunction ; drug therapy ; Humans ; Imidazoles ; therapeutic use ; Male ; Middle Aged ; Piperazines ; therapeutic use ; Sulfones ; therapeutic use ; Triazines ; therapeutic use ; Vardenafil Dihydrochloride ; Vasodilator Agents ; therapeutic use ; Yang Deficiency ; drug therapy ; Yin Deficiency ; drug therapy

Congenital bilateral absence of the vas deferens (CBAVD) is observed in 1%-2% of males presenting with infertility and is clearly associated with cystic fibrosis transmembrane conductance regulator (CFTR) mutations. CFTR is one of the most well-known genes related to male fertility. The frequency of CFTR mutations or impaired CFTR expression is increased in men with nonobstructive azoospermia (NOA). CFTR mutations are highly polymorphic and have established ethnic specificity. Compared with F508Del in Caucasians, the p.G970D mutation is reported to be the most frequent CFTR mutation in Chinese patients with cystic fibrosis. However, whether p.G970D participates in male infertility remains unknown. Herein, a loss-of-function CFTR p.G970D missense mutation was identified in a patient with CBAVD and NOA. Subsequent retrospective analysis of 122 Chinese patients with CBAVD showed that the mutation is a common pathogenic mutation (4.1%, 5/122), excluding polymorphic sites. Furthermore, we generated model cell lines derived from mouse testes harboring the homozygous Cftr p.G965D mutation equivalent to the CFTR variant in patients. The Cftr p.G965D mutation may be lethal in spermatogonial stem cells and spermatogonia and affect the proliferation of spermatocytes and Sertoli cells. In spermatocyte GC-2(spd)ts (GC2) Cftr p.G965D cells, RNA splicing variants were detected and CFTR expression decreased, which may contribute to the phenotypes associated with impaired spermatogenesis. Thus, this study indicated that the CFTR p.G970D missense mutation might be a pathogenic mutation for CBAVD in Chinese males and associated with impaired spermatogenesis by affecting the proliferation of germ cells.
Humans ; Animals ; Mice ; Male ; Mutation, Missense ; Retrospective Studies ; Cystic Fibrosis Transmembrane Conductance Regulator/genetics* ; Infertility, Male/genetics* ; Mutation ; Vas Deferens/abnormalities* ; Spermatogenesis/genetics*