Serum levels of inhibin B in men with different causes of spermatogenic failure

Inhibin B appears to be the physiological feedback signal for FSH. Herein the determination of serum levels of inhibin B, FSH, LH and testosterone in 148 infertile patients and their association with clinical findings and seminal parameters are reported. A significant negative correlation of FSH and inhibin B (r = -0.60) was found. LH levels showed a significant inverse correlation (r = 0.37), but a weak regression (c0 = 0.01). No correlation with testosterone levels occurred. A significantly positive correlation was observed between testis volume and inhibin levels (r = 0.39) as well as between sperm count and inhibin levels (r = 0.39). To evaluate whether the secretion of inhibin B depends on the nature of damage to the Sertoli cells, inhibin levels in 23 patients with varicocele; eight after cryptorchidism, and 16 after hemiorchiectomy were compared to those of other patients without these diseases, but identical sperm count. No significant differences were found. In 20 men undergoing testicular biopsy, inhibin levels were compared to histology. Although the men with Sertoli-cell-only syndrome had significantly lower levels ((15.83 +/- 12.2) pg ml-1) than those with normal spermatogenesis ((183.8 +/- 112.3) pg ml-1), a distinction between patients with hypospermatogenesis from those with normal spermatogenesis was not possible on the basis of inhibin levels. Between these groups, the distinction was better achieved by the FSH levels (sensitivity of 85%). We conclude that inhibin B levels are a serum marker of Sertoli cell function, but the prediction of the quality of spermatogenesis is not superior to that of FSH levels.     

Varicocele sclerotherapy improves serum inhibin B levels and seminal parameters

The usefulness of treating varicocele in order to improve fertility is still a matter of debate. The aim of this study was to evaluate variations in seminal parameters and inhibin B concentrations in a group of males affected by varicocele and treated by percutaneous retrograde sclerotherapy in comparison with a group of patients who did not undergo varicocele treatment. Thirty-eight patients with left varicocele underwent spermatic vein phlebography and percutaneous retrograde sclerotherapy with hydroxy-polyaethoxy-dodecanol. Serum inhibin B, follicle-stimulating hormone (FSH), testosterone levels and seminal parameters (sperm concentration, motility and morphology) were performed before and 6 months after sclerotherapy. Forty patients with left varicocele who did not undergo sclerotherapy were studied as controls. A significant increase (p < 0.01) in serum inhibin B levels and a significant decrease (p < 0.05) in FSH levels were observed 6 months after treatment. Semen analysis showed a significant improvement in sperm concentration (p < 0.05) and progressive motility (p < 0.01) after treatment. In control group no significant variations in hormonal and seminal parameters were observed 6 months after the basal examination. Six months after the basal evaluation, inhibin B levels were significantly higher in treated subjects than in controls (p < 0.05) whereas FSH levels were significantly lower (p < 0.05). Sperm concentration and progressive motility were significantly increased (p < 0.05 and p < 0.001, respectively) in treated subjects in comparison with controls. In conclusion, varicocele sclerotherapy improves inhibin B levels and seminal parameters, confirming the positive effect of this treatment on spermatogenesis and Sertoli cell function.     

Possible relationship between seminal plasma inhibin B and spermatogenesis in patients with azoospermia

Inhibin B is bidirectionally secreted by Sertoli cells, basal secretion into the circulation exerts negative feedback on follicle-stimulating hormone secretion, and serum inhibin B is considered a marker of spermatogenesis. The precise role of apical secretion is unknown. The objective of our work was to study the relationship between seminal inhibin B and spermatogenesis. Dimeric inhibin B was measured by immunoassay in seminal plasma of volunteers with normozoospermia (n = 10, group 1), in men after vasectomy (n = 10, group 2), and in men with azoospermia (n = 50, group 3). Testicular biopsy and testicular sperm extraction were performed in men with azoospermia. Seminal inhibin B levels were higher in men in group 1 than in men in groups 2 and 3 (P <.0001). In seminal plasma, inhibin B presents a positive correlation with alpha glucosidase activity (r =.37, P =.002). Seminal inhibin B is inversely related with serum FSH (r = -.58, P <.001), and presents a weak positive correlation with serum testosterone concentration (r =.29, P =.03). No difference was found between inhibin B levels in seminal plasma of patients with nonobstructive or obstructive azoospermia, and between positive or negative outcome of TESE. We conclude that inhibin B secretion by Sertoli cells is differentially regulated. The contribution of accessory sex glands limits the use of seminal plasma inhibin B as a marker of spermatogenesis.     

Relationships between serum hormone levels and semen quality among men from an infertility clinic

Participation rates in epidemiologic studies on semen quality are generally very low, raising concerns as to the potential for selection bias. Since hormones both initiate and maintain spermatogenesis, they may serve as surrogates of semen quality in epidemiologic studies. For this reason, in the present study, we explored the influence and predictive ability of reproductive and thyroid hormones on semen quality among men who were partners in an infertile couple. Between 1999 and 2003, 388 men were recruited from Massachusetts General Hospital Andrology Laboratory for clinical evaluation of fertility status. Fresh semen samples were assessed for quality (concentration, motility and morphology) and the serum levels of hormones, including follicle-stimulating hormone (FSH), luteinizing hormone (LH), inhibin B, sex hormone-binding globulin (SHBG), testosterone, free androgen index, free T4, total T3, and thyroid-stimulating hormone (TSH), were measured. Multiple logistic regression revealed increased odds for below-reference sperm concentration and morphology in men with increased FSH, and decreased odds for below-reference sperm concentration and motility in men with increased inhibin B. When FSH and inhibin B were divided into quintiles, the relationships with sperm concentration showed evidence of a threshold value. However, the ability of specific FSH (10 IU/L) and/or inhibin B (80 pg/mL) cutoff values to predict semen quality was lower than in previous reports. In multiple linear regression analysis, FSH and LH were inversely associated with sperm concentration, motility, and morphology. Inhibin B and free T4 were positively associated with sperm concentration, while there was a suggestive positive association between testosterone and sperm motility. In conclusion, we have found that FSH, LH, inhibin B, testosterone and free T4 levels are associated with human semen parameters. Additional consideration should be given to the utility of serum hormone levels as a surrogate for semen quality in epidemiologic studies in which the collection of semen is difficult due to logistical and/or volunteer rate constraints.     

Serum inhibin pro alphaC in infertile men.

Specific assays have been developed for bioactive inhibin dimers, inhibin A and B, and inhibin alpha-subunit precursor pro alphaC. To better understand the role of serum inhibin pro alphaC in infertile men, the authors measured these forms of inhibin in sera from 39 infertile men and analyzed inhibin relationships with serum gonadotropins, testosterone, and estradiol. All subjects had oligozoospermia. Inhibin A levels were undetectable in all subjects. Inhibin B concentrations were 117 +/- 59 pg/mL. Inhibit B concentrations correlated negatively with serum FSH (r = .584, p < .0001) and positively with sperm count (p < .01) and bilateral testicular volume (r = .607, p < .0001). The concentration of pro alphaC was 556 +/- 236 pg/mL (normal range, 446 +/- 28). Inhibin pro alphaC showed no correlation with serum FSH, LH, testosterone, sperm concentration, and bilateral testicular volume. In addition, inhibin pro alphaC was not correlated with inhibin B. Pro alphaC is unlikely to be a useful marker for spermatogenesis in infertile men compared with inhibin B.     

生育及不育男性血清及精浆抑制素-B水平分析

目的 :探讨生育及不育男性血清及精浆抑制素 B(inhibinB ,INHB)水平是否存在差异 ,了解血清及精浆INHB水平与精子发生的关系。　方法 :生育组 (n =2 0 )、少精子症组 (n =2 0 )、弱精子症组 (n =2 2 )和非阻塞性无精子症 (NOA)组 (n =2 0 )男性于上午 8∶0 0～ 10∶0 0留取精液和血液标本 ,进行精液常规分析 ,血清INHB、FSH、LH、T含量 ,精浆INHB、酸性磷酸酶、果糖、α 葡糖苷酶含量和活性测定。　结果 :血清、精浆INHB水平与血FSH均呈显著负相关 (r =- 0 .5 36 ,P <0 .0 0 1vsr =- 0 .2 88,P =0 .0 1) ,血清、精浆INHB水平与精子密度均呈显著正相关 (r=0 .49,P <0 .0 0 1vsr =0 .48,P <0 .0 0 1) ,血清INHB水平在生育组男性与少精子症组、NOA组男性间(分别为P <0 .0 5和P <0 .0 1)、弱精子症组与NOA组男性间 (P <0 .0 1)及少精子症组与NOA组男性间 (P <0 .0 5 )差异均有显著性 ,而精浆INHB变动范围较大 ,其水平仅在生育组男性与NOA组男性间及弱精子症组与NOA组男性间差异有显著性 (分别为P <0 .0 1和P <0 .0 5 )。精浆INHB水平与精浆α 葡糖苷酶活性呈正相关 (r=0 .377,P =0 .0 0 1)。血清INHB水平与精浆INHB水平间无相关性。　结论 :血清、精浆INHB水平均可反映睾丸的精子发生情况 ,精浆INHB水平还与     

Inhibin B levels in peripheral vein do not correlate with inhibin B levels in the spermatic vein in adolescents with varicocele

This study was conducted to evaluate the inhibin B with FSH and LH levels on spermatogenesis in varicocele patients. The study group consisted of 10 adolescent with left idiopathic varicocele of grade II and III. Blood specimens were obtained from dilated spermatic vein and peripheral vein simultaneously. Peripheral samples were also collected from 7 healthy children as controls. Inhibin B was measured with ELISA inhibin B kits. FSH and LH were analyzed by radioimmunoassay techniques. The results were analyzed using Mann-Whitney U and Spearman's rank tests. A value of p < 0.05 was considered significant. Peripheral FSH, LH and inhibin B levels were the same in the study and control group (p > 0.05). Mean inbibin B levels of spermatic vein were significantly higher than the control and peripheral blood of the study groups (p < 0.05). FSH, LH, and inhibin B levels correlated poorly each other (p > 0.05). Preoperative serum inhibin B concentration could not reliably predict a response to varicocelectomy, but the increase in inhibin B levels after treatment might suggest an improvement in testicular function.     

Serum inhibin B as a marker for spermatogenesis

Inhibin B generated by Sertoli cells provides negative feedback on FSH secretion. In men, inhibin B seems to be the physiologically important form of inhibin. Serum inhibin B was measured by two-site immunoenzymatic assay in 40 normal men (27 years of age) with sperm concentrations 100 +/- 9.2 x 10(6)/mL, 51 subfertile men (31 years of age) with sperm concentrations 6.8 +/- 0.8 x 10(6)/mL, 16 men with varicocele with sperm concentrations 54.3 +/- 0.8 x 10(6)/mL (31 years of age), men with hypogonadotrophic hypogonadism, men with Klinefelter syndrome, and men with obstructive and non-obstructive azoospermia. In men with normal sperm concentrations (>20 x 10(6) mL) serum inhibin B was 201 +/- 17 pg/mL and FSH 4 +/- 0.5 IU/L. Varicocele patients showed normal sperm concentrations > 20 x 10(6)/mL, normal serum inhibin B (173 +/- 21 pg/mL), and normal FSH levels (4.6 +/- 0.6 IU/L). In patients with sperm concentrations < 20 x 10(6)/mL the inhibin B level was 118 +/- 14 pg/mL and the FSH level was 10 +/- 1.1 IU/L. In all patients, except those with hypogonadotrophic hypogonadism and Klinefelter syndrome. inhibin B and FSH were inversely correlated (r = -.41, p > 0.01). There was a positive correlation between inhibin B and sperm concentrations (r = .34, p < .01). In varicocele men there was a correlation of r = .574, p < .05. Inhibin B may be a marker of exocrine testicular function and may offer an improved diagnosis of testicular dysfunction.     

alpha-1,4-Glucosidase activity in infertile oligoasthenozoospermic men with and without varicocele

This work aimed to assess seminal alpha-1,4-glucosidase activity in infertile oligoasthenozoospermic men associated with and without scrotal varicocele. Eighty men were investigated. They were divided into three groups: group 1 (n = 20), fertile normozoospermic men; group 2 (n = 30), oligoasthenozoospermia with varicocele; and group 3 (n = 30), oligoasthenozoospermia without varicocele. The patients underwent medical history, clinical examination, conventional semen analysis and estimation of seminal plasma alpha-1,4-glucosidase activity by double-beam spectrophotometer method and serum testosterone by radioimmunoassay method. There was a significant decrease in the mean seminal alpha-1,4-glucosidase activity levels in infertile men versus controls (mean +/- SD; 7.66 +/- 0.433, 2.088 +/- 0.565, 5.384 +/- 0.85 mU ml(-1) respectively). Mean serum testosterone levels demonstrated nonsignificant differences between studied groups. Seminal alpha-1,4-glucosidase activity levels demonstrated significant correlation with sperm count, sperm motility percentage and serum testosterone in oligoasthenozoospermia with varicocele group and demonstrated nonsignificant correlation in other groups. It is concluded that varicocele-induced hypoxia is the adverse effect that causes both oligoasthenozoospermia and decreased seminal alpha-1,4-glucosidase levels.     

Correlation of seminal parameters with serum lipid profile and sex hormones

The phospholipids and fatty acid composition of sperm are altered under the influence of serum lipids on impaired seminal parameters in infertile men. We studied the correlation of the serum lipid profile and sex hormone results of a group of infertile men with sperm characteristics of 18 infertile men. Semen samples were collected and analyzed. Serum fasted and post-meal glucose levels, insulin, total cholesterol, HDL, LDL, VLDL, triglyceride, FSH, LH, and testosterone measurements were performed. The increased serum VLDL, total triglyceride, and testosterone values were significantly correlated with decreased sperm motility. Serum FSH values were also inversely correlated with normal sperm morphology. The increased VLDL impaired seminal parameters; additionally, increased triglycerides may have deleterious effects on spermatogenesis. Deterioration is related with increased serum VLDL and triglyceride levels.     

精索静脉曲张不育症的内分泌变化

受试者有正常对照(12人),以及精索静脉曲张不育症精子减少(20人)和精子无力(12人)三组,分别用放免法测定血清积精液中的睾酮、双氢睾酮、促黄体生成素及促滤泡成熟激素。结果雄激素稍有降低,促黄体生成素和促滤泡成熟激素均有增高,尤以后者变化显著。本文对精索静脉曲张不育症的内分泌变化,精索静脉曲张引起的睾丸病变和功能损害,以及精索内静脉高位结扎治疗精子减少有较明显效果等问题进行讨论。     

精浆和血清生殖激素与精液质量的关系

目的为了评估精液质量不同的男性精浆和血清生殖激素的浓度与精子浓度及活动力的关系,探索精浆与血清生殖激素的关系。方法对301名男性进行精液检查,按照精液的质量参数将受试对象分成4组:精液正常组(n=176),弱精子症组(n=66),少精子症组(n=40)和非梗阻性无精子症组(n=19)。采用电化学发光免疫法测定各组受试对象血清卵泡刺激素(FSH)、黄体生成素(LH)、泌乳素(PRL)、孕酮(P)、睾酮(T)和雌二醇(E2)六项生殖激素和精浆PRL、T、P和E2四项生殖激素的浓度,比较组间差异并进行相关性分析。结果精液正常组和弱精子症组血清FSH和E2的浓度显著低于少精子症组和非梗阻性无精子症组(P0.05),精液正常组血清LH和P的浓度显著低于弱精子症、少精子症和非梗阻性无精子症的人群(P0.05);而精液正常、弱精子症和少精子症三组精浆PRL的浓度则高于非梗阻性无精子症组(P0.05)。除了非梗阻性无精子症组,受试者血清FSH的浓度与其精子浓度呈负相关(r分别为-0.350、-0.273和-0.448,P0.05)。精液正常组精浆PRL的浓度和精子的浓度之间呈正相关(r=0.269,P0.05);在少精子症组中,亦有相同趋势的相关性(r=0.432,P0.05)。结论精浆PRL及血清FSH的浓度能够反映精子浓度或活动力,在男性不育的病因分析中具有一定的指导价值。     

精索静脉曲张不育患者手术前后血浆性激素变化

将６４例单纯精索静脉曲张源性不育患者随机分为手术组３３例与非手术组３１例，分别于术前及术后６个月测血浆卵泡刺激素（ＦＳＨ）、黄体生成素（ＬＨ）、睾酮（Ｔ），同时测４６名正常生育力男性性激素作为正常值对照，对两组不育患者还进行了睾丸体积测定和精液分析。手术组采用经髂窝腹膜外单纯精索内静脉高位结扎术。结果：６４例精索静脉曲张源性不育患者精子密度、精子存活率、睾丸体积低于正常组，ＦＳＨ、ＬＨ、Ｔ均在正常值范围，与正常组对照无明显差异。两组手术前后对照分析，手术组与非手术组手术前后血浆性激素虽无统计学差异，但手术组患者术后精液质量、睾丸体积明显改善，随访一年手术组妊娠率（２７％）显著高于非手术组（１３％）。术前ＦＳＨ较高的患者术后精液质量、睾丸体积无明显改善，而术前ＦＳＨ正常者有显著差异。认为，精索静脉曲张不育患者通过手术治疗确能提高其生育能力，而术前根据血浆ＦＳＨ、ＬＨ、Ｔ测定结合睾丸检查、精液分析可以初步估计睾丸受损程度，对手术预后的判断有一定参考价值。     

Regional variations in semen quality of community-dwelling young men from Flanders are not paralleled by hormonal indices of testicular function

Epidemiological studies of sperm quality are hampered by problems such as low participation rates and poor comparability of results due to methodological differences in semen analysis. More objective sperm quality-related serum markers would facilitate worldwide comparisons of male reproductive status. Our objectives were to investigate to what extent a set of hormonal indices of testicular function, previously established in a clinical setting, could predict regional variations in seminal parameters in men from the general population. We recruited 101 men aged 20-40 years from two regions in Flanders, and assessed their sperm parameters and levels of serum reproductive hormones. In one region compared to another, the participants had lower sperm counts (by 34%; P=.06), lower total sperm counts (by 41%; P=.02) and poorer sperm morphology (by 32%; P<.001), which were paralleled by significantly lower levels of free testosterone (by 11%; P=.03), while for total testosterone (T) and follicle-stimulating hormone (FSH), the differences were not significant (both P=.09) at 10% and 17%, respectively. There were no differences in inhibin B and the T to luteinizing hormone (LH) ratio, which are markers of testicular function. Receiver operating characteristic curve analysis revealed that T:LH, inhibin B, and the inhibin B/FSH ratio had significant discriminatory power between men with sperm concentrations below or above 13.5x10(6)/mL. Regional variations in the semen quality of community-dwelling individuals are not necessarily reflected in altered hormonal indices of testicular function and thus, these markers, validated in clinical settings, are not valid substitutes for the traditional semen quality assessment used in epidemiological population studies.     

Leptin levels in infertile male patients are correlated with inhibin B, testosterone and SHBG but not with sperm characteristics

In the present study, differences in leptin levels between different groups of male patients presenting with infertility problems and possible correlations between leptin levels and clinical, spermiological, histological and hormonal characteristics were examined. Two hundred and ten male partners from infertile couples were included in the study. Based on clinical examination, spermiogram and testicular histology results, patients were divided into four groups: 42 men with non-obstructive azoospermia, 15 men with obstructive azoospermia, 68 men with oligoasthenoteratozoospermia and 85 men with normozoospermia. Serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), inhibin B, testosterone, sex hormone binding globulin (SHBG) and leptin were measured. After adjustment for body mass index, there was a negative correlation between serum levels of leptin and inhibin B, total testosterone and SHBG (r = -0.189, p = 0.009, r = -0.250, p = 0.001 and r =-0.221, p = 0.003 respectively) but there was no correlation between leptin and classical sperm characteristics. Our results therefore demonstrate a link between leptin and testicular function, independently of FSH and LH, possibly involving testosterone and SHBG through a regulation of Leydig cell function.     

Seminal plasma hormone profile in infertile men with and without varicocele

Seminal plasma FSH, LH, prolactin, testosterone, and oestradiol were estimated in 41 infertile men with varicocele and 45 infertile men without varicocele who failed to impregnate their wives after 2 years of marriage and 30 fertile men. There was significant elevation of FSH in the seminal plasma of the infertile men with varicocele compared with the seminal plasma of the other infertile and fertile men. Seminal LH and prolactin values were similar in both infertile groups but significantly higher than in the fertile men. Testosterone and oestradiol levels in the seminal plasma of infertile men with varicocele were lower than in the fertile and the other infertile males. Finding that both steroids were decreased in infertile men with varicocele could explain disturbed function of spermatozoa in men with varicocele. Further analysis will elucidate the importance of these hormone findings in the seminal plasma of infertile men with varicocele.     

慢性前列腺炎患者精浆果糖、微量元素与血清生殖激素水平的关系

本文对30例正常人及48例慢性前列腺炎(CP)患者进行了糖浆果糖、微量元素及血清FSH,LH及睾酮测定并进行了相关分析。结果表明CP者精浆锌、镁及钙含量较正常人明显减低,果糖含量差异不显著。CP者血清FSH、LH及睾酮水平均与正常人无明显差异。精浆果糖含量在CP者与LH显著正相关。正常人精浆锌、镁及钙分别与睾酮负相关,CP者不存在此关系。精浆铜、锰、铁及硒与血清生殖激素无关。     

Hormonal and Seminal Parameters in Infertile Men

500 infertile patients (250 with and 250 without left side varicocele) and 33 fertile men were evaluated as far as seminal parameters and the hormonal status were concerned. Sperm motility was constantly lower in infertile patients also when infertile group was compared to fertile one with the same sperm density. Serum testosterone levels were lower in infertile groups when compared to fertile men, and this confirms the existence of an androgenic deficit as a common finding in infertility associated or not to varicocele. FSH and LH increased (p less than 0.001) when sperm density dropped to less than 5 X 10(6) spermatozoa/ml. A negative correlation was found between both gonadotropins and sperm count (p less than 0.001), also after exclusion of azoo- and oligozoospermic (less than 5 X 10(6) spermatozoa/ml) patients (p less than 0.01). Gonadotropins were moreover tightly correlated between each other (p less than 0.001). Our data suggest that both gonadotropins are tightly tuned with sperm output and thus with the spermatogenic potential.     

Melatonin hormone profile in infertile males

Melatonin is a hormone produced by the pineal gland. There is much controversy about its relationship to the male reproductive process. In this study, seminal plasma as well as the serum melatonin levels were studied in different infertile male groups and were correlated with their semen parameters and hormonal levels. One hundred twenty male cases subdivided into six equal groups were consecutively included; fertile normozoospermic men, oligoasthenozoospermia (OA), OA with leucocytospermia, OA with varicocele, non-obstructive azoospermia (NOA) with high serum follicle stimulating hormone (FSH) and NOA with normal FSH. Semen analysis, estimation of melatonin, FSH, testosterone (T) and prolactin (PRL) hormone was carried out. Mean level of serum melatonin was higher than its corresponding seminal concentrations in all investigated groups with a positive correlation between their levels (r = 0.532, p = 0.01). Serum and seminal plasma melatonin levels in all infertile groups were reduced significantly compared with their levels in the fertile group. The lowest concentrations were in OA with leucocytospermia group. Melatonin in both serum and semen demonstrated significant correlation with sperm motility (r = 607, 0.623 respectively, p = 0.01). Serum melatonin correlated positively with serum PRL (r = 0.611, p = 0.01). It may be concluded that melatonin may be involved in the modulation of reproductive neuroendocrine axis in male infertility. Also, low levels of melatonin in semen were observed in infertile groups having reduced sperm motility, leucocytospermia, varicocele and NOA.     

Varicocele ligation on free testosterone levels in infertile men with varicocele

We have analyzed the effects of varicocele ligation on free testosterone levels, and investigated the interrelationships between free testosterone and fertility. The records were retrospectively evaluated for 42 infertile patients who underwent varicocele ligation, with serum free testosterone levels, follicle stimulating hormone (FSH), lutenizing hormone (LH), testosterone, estradiol, prolactin, ejaculated volume, sperm concentration and motility before and after surgery. Serum free testosterone levels increased from 12.97+/-4.16 to 13.59+/-3.93 pg/mL, but the difference was insignificant. The differences before and after surgery of patients in sperm concentration and motility were also insignificant. However, in free testosterone increasing group, the sperm concentration and motility increased significantly, from 4.05+/-4.35 to 7.90+/-8.19 million/mL (P=0.01) and from 30.64+/-21.87% to 41.00+/-22.00%, respectively (P=0.03). The increase in serum free testosterone level by varicocele ligation results in a significant improvement in sperm concentration and motility.