L-肉碱对糖尿病大鼠生精细胞凋亡及附睾精子数量和活动率的影响

目的:探讨L-肉碱(LC)对糖尿病(DM)大鼠生精细胞凋亡及附睾精子数量和活动率的影响。方法:24只雄性SD大鼠随机均分为3组,一组作为对照组,剩余两组分别注射链脲佐菌素(STZ,65 mg/kg)建立DM模型。建模成功后,各组大鼠分别给予如下灌胃剂量:对照组:生理盐水;DM模型组:生理盐水;LC组:300 mg/kgLC溶液,连续灌胃6周。末次给药24 h后,麻醉处死所有大鼠,分别进行附睾精子计数并检测精子活动率,流式细胞术检测各组大鼠睾丸生精细胞凋亡情况。结果:用LC治疗后的大鼠附睾头、尾精子活动率(%)分别为53.7±1.8和60.3±1.6,显著高于DM模型大鼠(分别为32.2±2.0和40.5±1.4,P<0.05),但低于对照组大鼠精子活动率63.1±2.4和68.9±1.3。与对照组附睾尾精子相对计数[(37.8±1.1)×106/100 mg]相比,DM组显著减少[(25.5±1.1)×106/100 mg],且具有统计学差异(P<0.05);LC治疗后大鼠附睾尾精子相对计数[(32.0±1.5)×106/100 mg]比DM组显著增加(P<0.05),但仍低于对照组。与对照组生精细胞凋亡率[(3.7±1.3)%]相比,DM组生精细胞凋亡率[(52.5±4.4)%]显著上升(P<0.05);经LC治疗后,LC组大鼠生精细胞凋亡率为(35.3±3.5)%,比DM组显著降低(P<0.05),但仍显著高于对照组。结论:LC(300 mg/kg)灌胃DM大鼠6周,可以减少DM大鼠生精细胞凋亡,增加附睾精子数量,提高精子活动率。     

还少胶囊对奥硝唑诱导的弱精子症模型大鼠生殖功能损伤的保护机制研究

目的:探讨还少胶囊对奥硝唑(ORN)诱导的弱精子症模型大鼠生殖功能损伤可能的保护机制。方法:将SD雄性大鼠随机分为4组,每组10只,分别是空白对照组、模型组、还少胶囊组和左卡尼汀组,除空白对照组外,其余3组采用ORN 400 mg/(kg·d)灌胃大鼠28 d,制成弱精子症大鼠模型。并同时连续给药28 d后,处死大鼠,检测大鼠附睾中左卡尼汀的含量,精子浓度、活率,附睾组织中有机阳离子转运子2(OCTN2)mRNA的表达,并观察大鼠睾丸组织病理结构。结果:还少胶囊组、阳性对照药左卡尼汀组与模型组相比,附睾左卡尼汀的含量均可明显提高(6 366.5、6 934.7 mg/L vs 2 880.3 mg/L,P<0.01);改善精子浓度[(46.19±14.23)、(42.25±6.11)×10~6/ml vs(34.58±10.25)×10~6/ml,P<0.01]、活率[(61.34±7.98)%、(61.34±7.98)%vs(42.59±7.54)%,P<0.01];上调附睾OCTN2 mRNA的表达量(27.26、27.15 vs 26.07,P<0.01);同时还少胶囊组能保护ORN造模导致的睾丸生精细胞的病理损伤,使生精细胞在生精小管形态、排列方式、生精细胞的活跃程度上与空白对照组更加接近。结论:还少胶囊对ORN诱导的弱精子症大鼠模型生殖功能损伤具有保护作用,能提高模型大鼠的精子浓度与活率,其机制可能与上调附睾OCTN2 mRNA的表达量、提高附睾左卡尼汀的含量有关。     

胶质细胞源性神经营养因子对体外培养大鼠精原干细胞PLZF和c-Kit表达的影响

目的 探讨胶质细胞源性神经营养因子(GDNF)对大鼠原代培养的精原干细胞(SSC)早幼粒细胞白血病锌指蛋白(PLZF)、原癌基因c-Kit基因转录及表达的影响.方法 采用含不同浓度GDNF(0、10、50、100 ng/m1)的DMEM培养液原代培养大鼠SSC.RT-PCR检测SsC中PLZF mRNA、c-Kit mRNA水平,蛋白质印迹法检测PLZF、c-Kit蛋白表达情况.结果 对照组和GDNF 10 ng/nl组细胞随着培养时间延长,生长速度无明显变化,而GDNF 50和100 ng/ml组细胞生长速度明显加快.对照组PLZF和c-Kit mRNA表达量分别为0.28±0.13、0.65±0.21,GDNF 10 ng/ml组分别为0.27±0.14,0.62±0.19,与对照组比较差异无统计学意义(P＞0.05);GDNF 50 ng/ml组分别为0.64±0.28、0.34±0.15.与对照组比较差异均有统计学意义(P＜0.05);GDNF 100 ng/ml组分别为0.68±0.27、0.28±0.18,与50 ng/ml组比较差异无统计学意义(P＞0.05).对照组PLZF和c-Kit蛋白表达量分别为0.34+0.13、0.72±0.27 GDNF 10 ng/ml组分别为0.38±0.18、0.69±0.26,与对照组比较差异元统计学意义(P＞0.05);GDNF 50 ng/ml组分别为0.68±0.26、0.35±0.15,与对照组比较差异有统计学意义(P＜0.05);GDNF 100 ng/ml组分别为0.70±0.27、0.32±0.11,与50 ng/ml组比较差异无统计学意义(P＞0.05).结论 随着GDNF浓度增加,SSC增殖水平升高,而分化受抑制.GDNF对SSC增殖和分化有一定的调控作用.     

Relationship of seminal plasma testosterone and dihydrotestosterone to sperm count and motility in man.

A radioimmunoassay previously described for serum T and DHT was adapted for use in the measurement of these hormones in seminal plasma. The seminal plasmas of 273 semen specimens were assayed for T and DHT concentration. Mean levels of these hormones for various sperm count and sperm motility categories were determined. We found that: (1) the DHT level of the azoospermic group was significantly lower than all other groups; (2) the T level of the group whose mean sperm count exceeded 40 x 10(6)/ml was higher than that of all other groups; (3) the DHT level of the group with absent sperm motility was lower than the level of all other groups; and (4) changes in sperm motility were not accompanied by changes in T levels. We concluded that idiopathic male subfertility as evidenced by oligospermia, azoospermia, and decreased sperm motility may be related to insufficient androgen production due to a primary intratesticular defect.     

Lack of correlation of selenium level in human semen with sperm count/motility

Considering the importance of selenium (Se) in male fertility, its concentration was measured in 211 semen samples from 211 normozoospermic, oligozoospermic, asthenozoospermic, and azoospermic men using the hydride generation atomic absorption spectrophotometry. No significant correlation of any kind existed between Se level in the seminal plasma and sperm count or motility. In view of the known poor correlation of these two frequently used semen parameters with the incidence of pregnancy, the assessment of the fertilizing potential of normozoospermic ejaculates with low Se levels is warranted.     

睾酮体外对人精子运动参数的影响

目的通过研究睾酮体外对人精子运动参数的影响,探讨睾酮在男性不育症治疗中的作用。方法10例健康生育男性手淫获得精液,经上游优化处理后的精子与不同浓度的睾酮孵育10、30、60min,10例弱精子症患者手淫取精并与睾酮孵育10、60、120min后,采用计算机辅助的精液分析系统(CASA)检测精子的运动参数。结果50ng/dl(1.73nmol/L)睾酮在体外能显著增强正常人精子的直线速度(VSL)、曲线速度(VCL)和平均速度(VAP),而对活率、前向运动百分率无明显影响,而100ng/dl(3.47nmol/L)睾酮使精子活率和前向性运动百分率均有明显下降(P<0.01);1.04nmol/L～1.73nmol/L浓度睾酮能显著增强弱精子症患者精子的活率、前向运动百分率及VSL,并随着浓度的增加,睾酮作用显著增强,而对VCL和VAP无明显影响。结论低浓度(1.04nmol/L～1.73nmol/L)睾酮在体外显著增高弱精症患者精子的运动参数。     

Effect of simulated microgravity on testosterone and sperm motility in mice

We examined changes in the serum testosterone level and in sperm in the testis and epididymis by using tail-suspended mice, which are a simulation model of the body fluid shift in space, to evaluate the possibility of spermatogenesis failure in space environment. We also studied pathological disorders of the testis in the tail-suspended mice. Tail suspension was imposed with a tail harness to a degree at which the hindlegs of mice did not touch the floor of the housing unit. In control mice, the tail was similarly fixed with a tail harness to impose the same stress, except that a hindleg remained on the floor. Body weight was not significantly different between the 2 groups during 7 days, and testicular weight was significantly different. The testosterone level was significantly lower in the tail-suspended group (0.71 +/- 1.24 ng/mL) than in the control group (2.38 +/- 3.50 ng/mL; P <.05). Microscopy with hematoxylin and eosin (HE) and periodic acid-Schiff (PAS) staining showed a small proportion of seminiferous tubules with impairment of spermatogenic function in the tail-suspended group, and multinucleated giant cells were occasionally noted. Terminal deoxynucleotidyl tranferase-mediated nick end-labeling staining revealed positive cells even in animals in which impairment was considered to be mild based on HE and PAS staining. Many cells showed intense p53 immunostaining compared to the control group, with more intense staining of the nucleus in the tail-suspended group. The proportion of motile sperm was slightly but not significantly reduced in the tail-suspended group. However, the mean movement velocity of the motile spermatozoa was significantly decreased.     

特发性弱精子症患者血清及精浆瘦素水平与精子活动力的关系

目的 通过研究特发性弱精子症(idiopathic asthenospermia,IAS)患者以及精液参数正常人群的血清、精浆瘦素,探讨瘦素与精子运动能力的关系.方法 IAS患者54例及精液参数正常者30例作为对照.常规CASA精液分析,放射免疫法检测血清及精浆瘦素.结果 排除体重指数差异的影响,(IAS患者与精液参数正常者体重指数比较差异无统计学意义,P>0.05),IAS患者血清瘦素水平与正常对照差异无统计学意义(P>0.05),而IAS患者精浆瘦素显著高于正常对照(P<0.05);精子活动率及精子活力与血清瘦素水平之间均无显著相关性(r=-0.213,P=0.249及r=-0.167,P=0.154),IAS患者的精子活动率及活力与精浆瘦素水平显著负相关(r=-0.31,P=0.034及r=-0.47,P=0.025).结论 IAS患者精浆瘦素水平显著增高,可能对精子运动能力有调控作用.     

Neutralization of cytokine activity at the receptor level improves sperm motility in men with spinal cord injuries

Men with spinal cord injury (SCI) have a unique semen profile characterized by normal sperm concentrations but abnormally low sperm motility. Previous studies showed that elevated concentrations of cytokines in the seminal plasma of these men contribute to this condition. For example, when elevated concentrations of interlekin-1beta (IL-1beta), IL-6, and tumor necrosis factor-alpha (TNF-alpha) were immunoneutralized in the semen of men with SCI, sperm motility improved. The present study investigated if these cytokines act on sperm cell receptors to inhibit sperm motility. Semen was collected from men with SCI and from healthy non-SCI men. Sperm were separated from the seminal plasma by centrifugation. Eight identical aliquots of 5,000 sperm suspended in 50 microL of seminal plasma were prepared for each subject. Agents were added to the aliquots in order to neutralize IL-1beta, IL-6, and TNF-alpha at the receptor level. In SCI subjects, sperm motility improved in each treatment group compared with the untreated group, but statistical significance was reached only when neutralizing agents to all 3 cytokines were added. Improvement was less pronounced in subjects with close to normal semen cytokine concentrations or close to normal pretreatment sperm motility. In control subjects, IL-1beta, IL-6, and TNF-alpha were within normal values, and addition of receptor blockers to semen had no effect on sperm motility. These data support the hypothesis that cytokines act at the level of the sperm receptor to inhibit sperm motility. These data further support the notion that inactivating semen cytokines leads to improved sperm motility in SCI men. Our goal is to develop this finding into a treatment for low sperm motility in men with SCI.     

Telfairia occidentalis‐supplemented diet induces changes in sperm parameters and testosterone level in rats

The growing patronage on herbal remedies and formulations from natural products in most developing countries has warranted research into certain health challenges including their antifertility effects. This study assessed the effects of boiled Telfairia occidentalis (TO) seed‐supplemented diets on the level of testosterone and semen quality in Wistar rats. Boiled TO seed diets at 10%, 15% and 30% were given to rats for 60 days. Our study showed that sperm quality was impaired as evidenced by the decreased number of motile spermatozoa, epididymal sperm numbers, percentage live/dead ratio and increased numbers of abnormal spermatozoa comparable to control values (p < .05). Feeding of rats with 10% and 15% TO seed‐supplemented diets increased testosterone levels nonsignificantly, while in the 30% TO seed diet animals, the level of serum testosterone was found to decrease significantly compared to control values. Furthermore, TO diet caused a nonsignificant increase in the activity of superoxide dismutase and the concentrations of reduced glutathione and malondialdehyde except for the significant increase in malondialdehyde level in the testes of the 10% TO diet group. A nonsignificant decrease in myeloperoxidase activity was also observed in the 10% and 15% but not 30% TO diet group. Histological damages characterised by severe loss of germ cells were more pronounced in the 10% TO diet group. Fourier transform infrared spectroscopy analysis of boiled TO seeds revealed the presence of esters, alkenes, hydroxyl and alcohol functional groups. Thus, boiled TO seed‐supplemented diet evoked antifertility effects in rats, and the effects on the toxicity end points investigated were not dose‐dependent.     

Patterns of hormones in the seminal plasma correlated with sperm count and motility

Seminal plasma FSH, LH, prolactin, and testosterone were estimated in 110 men with wives with no pregnancy during the last 24 months and 20 fertile males. Seminal FSH and LH levels were significantly higher in oligozoospermic men (sperm count over 10 X 10(6)/ml) and in males with reduced motility than in fertile men. Males with severe oligozoospermia (sperm count below 10 X 10(6)/ml) had values of gonadotropins similar to fertile subjects. Seminal prolactin levels were significantly elevated in all infertile males. Men with sperm count under 10 X 10(6)/ml had significantly lower seminal testosterone values than the other infertile and fertile men.