Genome-wide association study of semen volume, sperm concentration, testis size, and plasma inhibin B levels
Youichi SatoAtsushi TajimaMisaki KiguchiSuzu KogusuriAki FujiiTakehiro SatoShiari NozawaMiki YoshiikeMakiko MienoKosuke KojoMasahiro UchidaHaruki TsuchiyaK. YamasakiIssei ImotoTeruaki Iwamoto
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Genome-wide Association Study
Semen quality
Genetic Association
One hundred nine pre- and postmenopausal mammary carcinoma cases were studied to elucidate the role of sex hormone binding globulin (SHBG) in the hormone dependence of human breast cancer. Our findings indicate that there is a significant negative correlation between SHBG binding capacity and plasma testosterone concentration. All patients with high SHBG titers were found to be cytosol estrogen receptor (CER) positive and the plasma SHBG binding capacity of CER positive was significantly higher than that of CER negative patients. We also found that the level of pretherapy plasma SHBG concentration is a reliable indicator in predicting the efficacy of hormone therapy. Our findings also confirm that, for a tumor to be hormone dependent, high plasma SHBG concentration and estrogen receptors must be present simultaneously. The present pretherapy determination of SHBG titers is easier and more reliable than previous methods for determining the hormone dependence of human breast tumors.
Sex hormone receptor
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Infertility is a major reproductive health problem. Approximately 50% of all documented cases of infertility are attributable to male factors, such as poor testicular function and semen quality. The recent significant global decline in sperm counts has serious implications for male fertility, but the armamentarium for improving testicular function and semen quality is limited. Natural products have a wide range of activities and are a major source of drugs for disease prevention and treatment. To provide ideas and a theoretical basis for the research and development of therapeutic drugs for male infertility, this review summarizes natural products (mostly monomers) that have been shown to improve testicular function and semen quality and their possible mechanisms of action. These natural products primarily improve testicular function and semen quality via antioxidant, antiapoptotic, and anti-inflammatory effects, in addition to increasing serum testosterone and reducing DNA damage in spermatozoa and testicular cells. Prospects for the application of natural products in the treatment of male infertility are discussed.
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Summary Objective It is generally accepted that SHBG decreases the bioavailability and activity of testosterone (T). In in vitro experiments increased levels of SHBG will be associated with decreased levels of non‐SHBG bound testosterone (non‐SHBG‐T). However, in vivo SHBG can alter both production and clearance rates and thus plasma levels of T. Design and patients In order to study the effect of SHBG on the levels of non‐SHBG‐T in vivo in the presence of an active hypothalamo–pituitary–gonadal (HPG) axis we conducted a cross sectional study in 400 healthy adult men with an age range of 40–80 years and in 106 newborn boys. Measurements In both groups, regression coefficients (β) and partial correlation coefficients (r) were calculated for the relationship between SHBG and T or non‐SHBG‐T. Adult men were divided into age groups per decade (40–50 years, 51–60 years, 61–70 years and 71–80 years) to study possible differences in the impact of SHBG on the level of non‐SHBG‐T throughout ageing. Results Higher levels of SHBG were associated with higher levels of total testosterone in neonates (β = 0·02 ± 0·004, r = 0·44, P < 0·001) but not with non‐SHBG‐T (β = −0·001 ± 0·001, r = 0·05, P = 0·52). In adult men there was a significant age related increase in levels of SHBG and an age‐related decrease of both total and non‐SHBG‐T. Higher SHBG was strongly associated with higher total testosterone in all age groups (β = 0·26, 0·26, 0·26 and 0·23 for 40–50 years, 51–60 years, 61–70 years and 71–80 years, respectively, P < 0·001 for all age groups). Higher SHBG was not or only slightly associated with higher non‐SHBG‐T β = 0·02 ( P = 0·32), β = 0·04 ( P = 0·03), β = 0·04 ( P = 0·02) and β = 0·02 ( P = 0·16) for 40–50 years, 51–60 years, 61–70 years and 71–80 years, respectively. Conclusions In contrast to general belief, SHBG levels barely influence levels of non‐SHBG‐bound testosterone both in male newborns and healthy adult men: the influence, if any, is positive. Consequently the age related increase of SHBG does not account for the age related decline in non‐SHBG‐T in healthy adult men.
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We would like to follow up our 2014 publication in this journal (1) by submitting further validation data to support the measurement of salivary testosterone (T), highlighting its independence from variations in circulating sex hormone-binding globulin (SHBG), unlike serum total T which is positively correlated with SHBG.All analyses were performed as previously described (1).In addition, further samples were collected from, 48 males and 38 females, healthy volunteers (mean age 32 y, range 18-66).Ethical committee approval was granted from Ghent University Hospital.These samples were analysed for salivary T, total T and equilibrium dialysis using liquid chromatography-tandem mass spectrometry (2).
Free testosterone
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Semen quality
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Background: Male infertility encompasses up to 50% of all infertility cases and can be due to a variety of causes. Besides cytogenetic abnormalities, hormonal and environmental factors such as trauma, heat, toxins, radiation and nutritional deficiency have been shown to affect spermatogenesis. This study aims to look for the possible risk factors that impair the normal sperm production, which is reflected in semen analysis. Materials and Methods: A total of 601 men underwent semen analysis at Infertility Centre in this prospective case–control study. After undergoing semen analysis, those with azoospermia (AZ), oligozoospermia (OL) and asthenozoospermia (AS) were selected as cases of the study, whereas those with normal semen analysis results were selected as controls. All participants were interviewed with a standardised questionnaire to assess for the known & possible risk factors of infertility & data was analysed. Results: Mean & standard deviation (SD) age of the participants was 33.38 ± 5.63 years. History of varicocele was found to be significantly associated with AZ/OL [adjusted odds ratio (ORadj) 5.4] and AS (ORadj 6.9). Similarly, men with a history of mumps orchitis had a significant association with both AS (ORadj 2.13) and OL/AZ (ORadj 2.62). Men who chewed tobacco had about twice more chances of having OL/AZ. Activities related to scrotal heat exposure except hot water bath were not associated with sperm quality [AS (ORadj 0.68) and OL/AZ (ORadj 0.59)]. Motorcycle riders were found to have decreased association with low semen quality AS (ORadj 0.53) and OL/AZ (ORadj 0.50). Conclusion: Varicocele, mumps orchitis and tobacco chewing are significant risk factors that have shown to decrease semen quality and can contribute to male infertility.
Semen quality
Semen Analysis
Asthenozoospermia
Oligospermia
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Serum sex-hormone binding globulin (SHBG) and testosterone were measured in 52 samples from 15 female patients with anorexia nervosa. There was a significant correlation between body weight and serum levels of SHBG and testosterone. Moreover, the correlation between serum SHBG and relative weight 1055 suggests that serial measurement of serum SHBG might be a useful parameter in the management of patients with anorexia nervosa.
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Results of in vitro experiments indicate that with increasing concentrations of SHBG, testosterone (T) is preferentially bound to SHBG in comparison with estradiol (E2). In these studies, the ratio of non-SHBG-bound E2 (non-SHBG-E2) to non-SHBG-T increased with increasing levels of SHBG. SHBG has consequently been regarded as an estrogen amplifier. In this cross-sectional study in 399 men aged between 40 and 80 yr we tested whether higher levels of SHBG are associated with a higher estrogen/androgen ratio in vivo. The mean T level of these men was in the eugonadal range [536 +/- 152 ng/dl (18.6 +/- 5.26 nmol/liter), mean +/- sd]. With increasing SHBG levels the non-SHBG-bound fraction of T decreased from 80 to 36% and that of E2 from 89 to 53%. Higher levels of SHBG were associated with higher levels of both total T [regression coefficient (beta) after adjustment for age and body mass index, 286 +/- 15.8; P < 0.001] and total E2 (beta = 4.47 +/- 0.90; P < 0.001). However, SHBG levels were negatively related with levels of non-SHBG-E2 (beta = -1.78 +/- 0.69; P < 0.001), whereas there was a positive association between levels of SHBG and non-SHBG-T (beta = 32.0 +/- 9.78; P = 0.001). Furthermore, we observed a negative relationship between SHBG levels and the E2/T ratio of either total (beta = -0.016 +/- 0.002; P < 0.001) or non-SHBG-bound (beta = -0.011 +/- 0.002; P < 0.001) hormone. Therefore, we conclude that in eugonadal men, higher SHBG levels are associated with lower levels of non-SHBG-E2 but slightly higher levels of non-SHBG-T. This means that SHBG cannot be regarded as an estrogen amplifier in eugonadal men.
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Semen analysis is the preliminary investigation for evaluation of male infertility. Spontaneous pregnancy is difcult in couples when male partner has abnormal semen parameters. A lot of physical and environmental factors inuence semen quality. Early identication and addressing of these issues can help resolve the burden of infertility cases. In our study we want to highlight the prevalence of male infertility and their associated etiological factors in an industrial area in Hyderabad. Over 80% of our patients showed abnormal semen analysis results. Asthenozoospermia was the most common abnormality. The recent trends show that 'Male factor infertility' is on rise and it should be treated as a global problem. Increased prevalence of oligozoospermia and asthenozoospermia are contributing towards abnormal semen quality. There are many related factors like cigarette smoking, alcohol consumption, varicocele, and industrial toxin exposure. Prompt diagnosis, proper counselling and removal of these etiological agents will result in improvement of male fertility.
Asthenozoospermia
Semen quality
Etiology
Abnormality
Semen Analysis
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