Sperm concentration and normal sperm morphology decrease and follicle-stimulating hormone level increases with age

Re-assessment of the close relationship between serum FSH levels and semen quality: a retrospective cohort study of 11,929 Chinese men

PURPOSE

To establish a medically valuable normal reference interval of follicle-stimulating hormone (FSH) levels in males with normal semen and to assess the predictive value of FSH in males exhibiting semen abnormalities.

METHODS

The study involved male patients who underwent their initial serum sex hormone test and semen test between October 2013 and June 2023. The reference interval was identified as the 95% confidence interval (CI) of FSH values in the patients with normal semen parameters. Then, in the total study population, receiver operating characteristic (ROC) curves were performed to evaluate the discriminatory ability of FSH for oligozoospermia and non-obstructive azoospermia (NOA). Besides, multivariable logistic regression was performed to investigate the association of FSH with oligozoospermia and NOA adjusted by age.

RESULTS

A total of 11,929 patients were finally enrolled in the study. The normal reference interval of FSH ranged from 1.70 IU/L to 7.60 IU/L (median: 3.98 IU/L) based on 4595 patients with normal semen routine parameters. In the total patients, ROC curves showed FSH to have a "fair" discriminatory ability for oligozoospermia (area under receiver operating characteristic curve (AUC) 0.747, threshold 7.32 IU/L, accuracy 0.734, positive predictive value (PPV) 0.754, negative predictive value (NPV) 0.726), while ROC curves showed FSH to have a "excellent" discriminatory ability for NOA (AUC: 0.921, threshold 10.18 IU/L, accuracy 0.903, PPV 0.593, NPV 0.972). Besides, multivariable logistic regression showed that FSH ≥ 7.32 IU/L was associated with a 8.51-fold increase in the risk of oligozoospermia adjusted by age, while FSH ≥ 10.18 IU/L was associated with a 38.93-fold increase in the risk of NOA.

CONCLUSIONS

Our findings indicated that the reference interval for FSH in males with normal semen was 1.70-7.60 IU/L and found that FSH was capable of effectively discerning oligospermia and NOA.

Seminal Calbindin 2 in Infertile Men With Varicocele: A Prospective Comparative Study

The present study compared seminal calbindin 2 (CALB 2) levels and semen parameters in men with and without varicocele. CALB 2 is also known as calretinin and 29 kDa calbindin. The study was a case-control study conducted from April (2021) to March (2022) in the andrology department at Beni-Suef University hospital. The study included four matched groups: group (I) were controls (fertile normozoospermic men without varicocele) (n=24). Group (II) were fertile normozoospermic men with varicocele (n=24). Group (III) were infertile oligoasthenoteratozoospermia (OAT) men without varicocele (n=24). Group (IV) were infertile OAT men with varicocele (n=24). The lowest levels of seminal CALB 2 were found in patients with severe oligozoospermia which showed a statistically significant difference when compared to seminal CALB 2 in patients with normal, mildly low, or moderately low sperm counts. There were significant negative correlations between sperm concentration, sperm motility and percentage of normal sperm forms and seminal CALB 2. Seminal plasma CALB 2 may play a role in the negative impact of varicocele on the semen parameters especially sperm concentration, sperm motility and percentage of sperm normal forms. Future studies are needed to verify these findings.

Age-related changes in sperm traits and evidence for aging costs of sperm production in a sexually promiscuous passerine

In many animal species, organismal performance declines with age in a process known as aging or senescence. Senescence typically leads to a deterioration of physiological functionality and can impact the development of primary sexual phenotypes. Sperm production is a complex and costly process that is sensitive to changes in individual physiological state, yet remarkably little is known about age-related changes in sperm performance and aging costs of sperm production. Here we use a non-linear generalized additive mixed models (GAMM) modelling to evaluate age-related changes in postcopulatory sexual traits in the European barn swallow (Hirundo rustica rustica), a relatively short lived sexually promiscuous passerine species, where male extra-pair fertilization success has been shown to increase with age. We confirmed a positive relationship between sperm midpiece length and sperm velocity in this species. Within-male changes in sperm morphology and sperm velocity were in general absent, with only sperm length decreasing linearly with increasing age, although this change was negligible compared to the overall variation in sperm size among males. In contrast, the cloacal protuberance (CP) size changed nonlinearly with age, with an initial increase between the first and third year of life followed by a plateau. The results further indicate the existence of a trade-off between investments in sperm production and survival as males with large CP tended to have a reduced lifespan. This seems consistent with the idea of expensive sperm production and survival aging costs associated with investments in post-copulatory traits in this sexually promiscuous species.

Blood hormones and suicidal behaviour: A systematic review and meta-analysis

This study was to evaluate the relationship between blood hormone levels and suicidal behaviour. We reviewed Web of Science, PubMed and Embase for literature published up to 10 April 2022. Studies were restricted to English-language articles. Studies measuring blood hormone levels in suicidal and non-suicidal subjects were eligible. Standardized mean differences (SMDs) were applied to evaluate group differences. Overall, 57 studies were eligible, of which 51 evaluated suicide attempts, and 9 assessed suicidal ideation. Random-effects meta-analysis indicated that levels of thyrotropin stimulating hormone (TSH) (SMD = 0.50; 95% CI, 0.27-0.72), leptin (SMD = -1.16; 95% CI, -1.94 to -0.38) and dehydroepiandrosterone sulfate (DHEAS) (SMD = -0.67; 95% CI, -1.13 to -0.21) were related to suicide attempts, whereas progesterone levels (SMD = 0.22; 95% CI, 0.03-0.41) were related to suicidal ideation. This analysis offers evidence linking abnormalities of blood hormones with suicidal behaviour, which may be essential for identifying individuals with suicide attempts and suicidal ideation. Large prospective studies are needed for further clarification of roles of hormones in suicidal behaviour.

Echis ocellatus Venom-Induced Reproductive Pathologies in Rat Model; Roles of Oxidative Stress and Pro-Inflammatory Cytokines

This study reported reproductive pathologies associated with Echis ocellatus venom in animal model. Twenty male Wistar rats with body weight between 180 and 220 g were selected randomly into two groups (n = 10). Rats in group 1 served as the control while rats in group 2 were envenomed with a single intraperitoneal injection of 0.055 mg/kg−1 (LD6.25) of E. ocellatus venom on the first day and a repeated dose on the twenty fifth day. Both control and envenomed rats were monitored for fifty consecutive days. The venom caused a significant (p < 0.05) reduction in sperm motility, count, and volume, with increased sperm anomalies in envenomed rats compared to the control. Likewise, serum concentrations of male reproductive hormones were significantly (p < 0.05) higher in envenomed rats. Increased levels of malondialdehyde were accompanied by a significant (p < 0.05) decrease in reduced glutathione and catalase activity in the epididymis and testis tissues of envenomed rats. The venom enhanced the release of epididymal and testicular tumor necrosis factor-alpha and interleukin1-beta compared to the control. Furthermore, severe pathological defects were noticed in tissues of the testis and epididymis of envenomed rats. This study demonstrated that E. ocellatus venom toxins can induce reproductive dysfunction in male victims of snake envenoming.

Pregnancy Achievement by Medical Assisted Reproduction Is Correlated to the G Protein-Coupled Receptor 30 mRNA Abundance in Human Spermatozoa

Estrogens, specifically 17β-estradiol (E2), play an important role in male health, including male fertility. The G protein-coupled receptor for estrogen 30 (GPR30) is essential for mediating the rapid non-genomic effects of E2 on a variety of testicular cells, including spermatozoa, although its molecular effects remain largely unknown. In this work, we hypothesized that the GPR30 mRNA abundance in spermatozoa could be correlated to sperm quality. Sperm GPR30 mRNA could also be carried into the oocyte, potentially impacting embryo development and the success of a pregnancy. For this study, 81 sperm samples were collected from couples seeking fertility treatment and undergoing medically assisted reproduction treatments (ART), following the World Health Organization guidelines. GPR30 mRNA abundance in spermatozoa was assessed with a quantitative polymerase chain reaction. The resulting data show that there is no correlation between the abundance of the GPR30 transcript with paternal BMI, age, or sperm quality parameters. Interestingly, we observed that higher levels of GPR30 mRNA abundance in spermatozoa were related to the achievement of biochemical pregnancy and clinical pregnancy (p < 0.05) by couples undergoing treatment. These results highlight the role of the sperm’s RNA cargo in offspring development, suggesting that spermatozoa mRNA content can influence ART success.

"Seminal testosterone", rising viewpoint of local spermatogenesis in nonobstructive azoospermia: One center long-term bidirectional cohort study

OBJECTIVE

Reproductive hormones are a traditional good method to evaluate spermatogenesis but might not accurately represent local spermatogenesis. To find a more accurate method, seminal reproductive hormones were studied.

METHODS

A bidirectional cohort study was performed. A total of 126 infertile men from 2018 to 2019 were retrospectively analyzed. They were divided into nonobstructive azoospermia (NOA), oligozoospermia (OLZ) and normal (NOR) groups. A prospective study was conducted on patients in the NOA and OLZ groups for 2 years. Microscopic testicular sperm extraction was performed for NOA patients, who were divided into a focal spermatogenesis group (FS) and an idiopathic azoospermia group (IA). Drug treatment was for OLZ patients, who were divided into a valid group (VA) and an invalid group (IN). The differences in sperm parameters and reproductive hormones were compared. ANOSIM analysis was used between and within groups. Pearson correlation analysis, CO inertia analysis and Proctor's analysis were for relationships. ROC curve for the specificity and sensitivity. Time series analysis was for the trends between hormones and time.

RESULTS

The b-FSH, b-LH, s-T and ΔT in the NOA group were significantly higher than those in the OLZ and NOR groups. However, the s-FSH, s-E₂, s-P, ΔFSH, ΔLH, ΔP and ΔE₂ were lower. Thirty-one NOA patients underwent MTSE, of whom 12 had sperm (FS) and 19 had no sperm (IA). The s-FSH and s-E₂ of the FS group were higher than those of the IA group. Twenty-six OLZ patients completed 30 days of treatment, of which 11 had an improved sperm count (VA) and 15 had no (IN). The ΔT of the VA group was higher than that of the IN group. After follow-up for 2 years, 18 patients' results showed that b-FSH, b-LH and s-T were different over time, with delays of 19, 3 and -19 days. SC is closely related to pH, s-FSH, s-LH, s-E₂, s-P, s-T, b-FSH, b-LH, ΔFSH, ΔLH, ΔP, ΔE₂ and ΔT. There were complex common trends and relationships between different kinds of hormones. s-FSH, s-LH, s-E₂, s-P, s-T, b-FSH and b-LH were useful to judge spermatogenesis, of which s-T, b-FSH and b-LH were more sensitive. If s-T, b-FSH and b-LH reached 64.4, 9.4 and 4.7, respectively, their prediction performance was the strongest.

CONCLUSION

Seminal testosterone is sensitive for judging local spermatogenesis in nonobstructive azoospermia patients, which may be the direction of local spermatogenesis in nonobstructive azoospermia.

CLINICAL TRIAL REGISTRATION

http://www.chictr.org.cn/index.aspx, identifier ChiCTR2200060463.

Physiologic Testicular Uptake of 18-F Fluorodeoxyglucose in the Indian Population

Objective

The objective of the study is to assess the physiologic uptake of testes in patients undergoing ¹⁸F-fluoro-2-deoxyglucose (FDG) position emission tomography/computed tomography (PET/CT) scans for various malignancies other than testicular malignancy.

Materials and Methods

The testicular uptake of ¹⁸F-FDG expressed as the standardized uptake value (T) was measured on PET/CT images in 320 men with no known testicular pathology from July 2019 to March 2020 at Tata Main Hospital, Jamshedpur. The ratio of maximum standardized uptake value (SUVmax) of the testis (T) to SUVmax of muscle (M) T/M ratio and to SUVmax of the liver (L) T/L ratio was calculated using SUVmax of right adductor muscle and liver, respectively. Testicular volume was calculated with the measurements taken from the axial, coronal, and sagittal slices of CT images. The correlation of testicular uptake with age, blood serum glucose level, and testicular volume was also analyzed.

Results

The mean age of 320 men was 57 ± 15 years (range: 10-94) and the mean blood glucose level was 107.7 ± 23.5 mg/dl (range: 64-175). Mean testicular SUVmax in 320 men was 2.48 ± 0.80 (range: 0.67-5.5). The mean testicular volume of 640 testes of 320 men was 18.80 ± 4.83 cm³ (range: 3.85-33.56 cm³). The mean values of (T/M) and (T/L) ratios in the studied population were 3.64 ± 1.21 (range: 1.08-5.58) and 0.97 ± 0.251 (range: 0.34-1.88), respectively. The laterality index (L - R/(L + R) ×2) in 320 men was 0.074 ± 0.050 (0.000-0.308). There was a minimal negative correlation between testicular SUVmax and age (r = -0.136, P = 0.15). Mild negative correlation was noted between T/M ratio and age (r = -0.291, P < 0.0001) and between T/L ratio and age (r = -0.182, P = 0.001) in the studied population.

Conclusion

The physiological testicular FDG uptake (SUVmax) of testes was 2.48 ± 0.80 (0.67-5.5) among the Indian population in this study, which has a mild negative correlation with age.

Genetic Association of the Functional WDR4 Gene in Male Fertility

Infertility is one of the important problems in the modern world. Male infertility is characterized by several clinical manifestations, including low sperm production (oligozoospermia), reduced sperm motility (asthenozoospermia), and abnormal sperm morphology (teratozoospermia). WDR4, known as Wuho, controls fertility in Drosophila. However, it is unclear whether WDR4 is associated with clinical manifestations of male fertility in human. Here, we attempted to determine the physiological functions of WDR4 gene. Two cohorts were applied to address this question. The first cohort was the general population from Taiwan Biobank. Genomic profiles from 68,948 individuals and 87 common physiological traits were applied for phenome-wide association studies (PheWAS). The second cohort comprised patients with male infertility from Wan Fang Hospital, Taipei Medical University. In total, 81 male participants were recruited for the genetic association study. Clinical records including gender, age, total testosterone, follicle-stimulating hormone (FSH), luteinizing hormone (LH), total sperm number, sperm motility, and sperm morphology were collected. In the first cohort, results from PheWAS exhibited no associations between WDR4 genetic variants and 87 common physiological traits. In the second cohort, a total of four tagging single-nucleotide polymorphisms (tSNPs) from WDR4 gene (rs2298666, rs465663, rs2248490, and rs3746939) were selected for genotyping. We found that SNP rs465663 solely associated with asthenozoospermia. Functional annotations through the GTEx portal revealed the correlation between TT or TC genotype and low expression of WDR4. Furthermore, we used mouse embryonic fibroblasts cells from mwdr4 heterozygous (+/‒) mice for functional validation by western blotting. Indeed, low expression of WDR4 contributed to ROS-induced DNA fragmentation. In conclusion, our results suggest a critical role of WDR4 gene variant as well as protein expression in asthenozoospermia.

Testicular volume and clinical correlates of hypothalamic-pituitary-testicular function: A cross-sectional study in obese men

The aim of this study was to determine whether testicular volume is correlated with clinical and biochemical markers of hypothalamic–pituitary–testicular (HPT) axis function. This was a cross-sectional substudy of a larger randomized controlled trial including obese men, body mass index (BMI) ≥30 kg m⁻², with a total testosterone level <12 nmol l⁻¹. Testicular volume was measured by orchidometer, testosterone by liquid chromatography/tandem mass spectrometry, and body composition by dual-energy X-ray absorptiometry. Men completed the Aging Males' Symptoms (AMS) score, International Index of Erectile Function-5 (IIEF-5), physical function, and handgrip dynamometer testing. Eighty-nine men participated with a median (interquartile range [IQR]) age of 53.1 (47.6, 59.2) years, BMI of 37.0 (34.6, 40.5) kg m⁻², and a total testosterone of 7.0 (6.1, 7.9) nmol l⁻¹. Median testicular volume was 18 (IQR: 10, 20) ml. Testicular volume was negatively correlated with BMI (τ = −0.1952, P = 0.010) and total fat mass (τ = −0.2115, P = 0.005) independent of age and testosterone. When BMI, testosterone, sex hormone-binding globulin (SHBG), and luteinizing hormone (LH) were present in a multivariable model, only BMI (-0.38 ml change in testicular volume per 1 kg m^-2 BMI; 95% CI: −0.74, −0.02; P = 0.04) and LH (-0.92 ml change in testicular volume per 1 IU l^-1 LH; 95% CI: −1.75, −0.095; P = 0.03) remained independent significant predictors of testicular volume. Testicular volume was positively correlated with IIEF-5 (τ = 0.2092, P = 0.021), but not related to handgrip strength, physical function tests, or AMS. In obese men, testicular volume is inversely and independently associated with measures of adiposity, but not with most clinical or biochemical markers of HPT axis action. From a clinical perspective, this suggests that obesity might compromise the reliability of reduced testicular volume as a sign of androgen deficiency in men.

Influence of age on sperm characteristics evaluated by light and electron microscopies

The impact of male aging on male fertility has only recently become of interest to the scientific community. This study aims to assess the relationship between age and fertility among a sample of men, considering the individual and pathological characteristics. In this retrospective study data of semen analysis and medical history of 1294 Italian male patients were considered. Semen analysis was performed by light microscopy and transmission electron microscopy mathematically elaborated. A generalized linear model was used to explore the influence of male age on semen quality, considering as confounders wine consumption, smoking habits, presence of varicocele, consanguinity and positive semen bacteriological analysis and urethral swab. The mean age of the participants was 36.41 ± 6.379. Male aging without impact of confounders was correlated with a decrease in sperm concentration and motility and an increased in sperm necrosis. Sperm concentration and progressive motility were negatively related to the presence of confounders as wine consumption (sperm motility), urogenital infection (sperm concentration and motility), varicocele (sperm concentration) and consanguinity (sperm motility). Urogenital infection, varicocele and consanguinity positively correlated with sperm necrosis. The most important finding was the observation of a negative effect of male aging on sperm parameters such as concentration, motility, and viability. It is possible to hypothesize age-dependent changes of testicular environment, probably related to reactive oxygen species production. The demonstration, in a large sample of patients, that aging influences sperm quality strongly motivates further research focused on the mechanisms involved in this phenomenon and its effects on offspring fitness.

Peroxiredoxin 4, a new oxidative stress marker in follicular fluid, may predict in vitro fertilization and embryo transfer outcomes

Background

Peroxiredoxin 4 (Prdx4), a member of the Prdx family, can catalyze the reduction of reactive oxygen species. This study aims to explore whether Prdx4 can serve as an effective marker in follicular fluid (FF) for predicting in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycle outcomes.

Methods

In this prospective study, all participants were recruited from the center of clinical reproductive medicine from 2017 September to 2018 December. Women with tubal or male factor infertility undergoing their first IVF/ICSI cycle were recruited (n=138). FF samples from each patient were collected on the day of oocyte retrieval. Prdx4 concentrations were measured, and the correlation between Prdx4 levels and IVF outcomes was analyzed.

Results

The results showed that pregnant women had higher levels of Prdx4 than nonpregnant women. Prdx4 was positively correlated with the oocyte fertilization rate (r =0.334; P=0.011) and good quality embryo rate (r =0.326; P=0.013). Furthermore, we found that the clinical pregnancy rate was positively correlated with Prdx4 levels in a concentration-dependent manner in the Prdx4 quartiles (<13.38, 13.83–16.93, 16.93–22.93, >22.93 ng/mL). The fertilization rates, clinical pregnancy rates and live pregnancy rates were all significantly higher in the highest Prdx4 quartile group than in the lowest quartile. Moreover, the results indicated that Prdx4 had an area under the receiver operating characteristic curve (AUC) of 0.754, corresponding to an optimal cutoff point of 22.30 ng/mL.

Conclusions

Our results provide evidence that higher expression of antioxidants, such as Prdx4, in the FF of IVF patients tends to indicate a higher likelihood of pregnancy through an oocyte quality mechanism.

Impact of nicotine, alcohol, and cocaine exposure on germline integrity and epigenome

Converging evidence suggests that parental exposure to drugs of abuse can affect offspring phenotypes. The impacts of drug abuse on germ cell quality may mediate multigenerational and transgenerational inheritance, although biological pathways underlying this mode of inheritance are not yet characterized. Germline epigenetic marks are modified by drug exposure and have emerged as promising mechanistic candidates in recent work. Drug exposure also impacts overall germline integrity and reproductive functioning, although the role of these consequences in multi/transgenerational inheritance is unclear. This review synthesizes literature on effects of exposure to alcohol, cocaine, and nicotine on the germline with a focus on epigenetic modifications following drug exposure and broader impacts on germline integrity and reproductive functioning. We discuss potential interactions between reproductive functioning, germline integrity, and germline epigenome/transcriptome in pathways underlying multi/transgenerational inheritance. We find that existing data may support independent or interactive contributions of these germline impacts on offspring phenotypes in a manner that may mediate multi/transgenerational inheritance.

Semen quality pattern and age threshold: a retrospective cross-sectional study of 71,623 infertile men in China, between 2011 and 2017

BACKGROUND

The aim of this study was to provide information on the semen quality pattern of infertile men and age thresholds for semen parameters in China.

METHODS

This was a retrospective cross-sectional study investigating 71,623 infertile men from the Reproductive and Genetic Hospital of CITIC Xiangya in Hunan, China, from 2011 to 2017. The Kruskal-Wallis test, Mann-Kendall test, linear regression model and joinpoint regression were used.

RESULTS

Although erratic changes were observed in the median semen parameters (sperm concentration 40.1-52.1 × 10⁶/ml, total sperm count 117.8-153.1 × 10⁶, sperm progressive motility 33.4-38.1%) during the 7 years of observation, no significant decrease in semen quality was found, and 47.88% of infertile men showed normal semen parameters according to the World Health Organization (WHO) criteria. According to the joinpoint regression analysis, sperm progressive motility appeared to decrease earlier than the sperm concentration and total sperm count (at 28, 58, and 42 years of age, respectively).

CONCLUSIONS

There is no evidence of a deterioration in semen quality among infertile men in Hunan, China. Semen parameters decreased with increasing age, with turning points noted at different ages. Semen parameters are not absolute evidence for the assessment of male fertility potential. Therefore, we believe that, among semen parameters, the sperm concentration is the best predictor of fertility for ART, followed by motility. Decreased sperm motility may affect natural pregnancy, but it is not necessary for successful IVF.

mTOR Signaling Pathway Regulates Sperm Quality in Older Men

Understanding how age affects fertility becomes increasingly relevant as couples delay childbearing toward later stages of their lives. While the influence of maternal age on fertility is well established, the impact of paternal age is poorly characterized. Thus, this study aimed to understand the molecular mechanisms responsible for age-dependent decline in spermatozoa quality. To attain it, we evaluated the impact of male age on the activity of signaling proteins in two distinct spermatozoa populations: total spermatozoa fraction and highly motile/viable fraction. In older men, we observed an inhibition of the mechanistic target of rapamycin complex 1 (mTORC1) in the highly viable spermatozoa population. On the contrary, when considering the entire spermatozoa population (including defective/immotile/apoptotic cells) our findings support an active mTORC1 signaling pathway in older men. Additionally, total spermatozoa fractions of older men presented increased levels of apoptotic/stress markers [e.g., cellular tumor antigen p53 (TP53)] and mitogen-activated protein kinases (MAPKs) activity. Moreover, we established that the levels of most signaling proteins analyzed were consistently and significantly altered in men older than 27 years of age. This study was the first to associate the mTOR signaling pathway with the age impact on spermatozoa quality. Additionally, we constructed a network of the sperm proteins associated with male aging, identifying TP53 as a central player in spermatozoa aging.

Toxic Effects of Trazodone on Male Reproductive System via Disrupting Hypothalamic-Pituitary-Testicular Axis and Inducing Testicular Oxidative Stress

Depression and anxiety are recognized as public health problems. Epidemiological studies have shown that depression and anxiety often occur during reproductive ages between 20 and 60 years of age in males. Trazodone is one of the most frequently prescribed drugs in the treatment of depression and anxiety. Drugs used in repeated doses also play a role in the etiology of infertility. In our study, it was aimed to identify the possible toxic effects of trazodone on male rats and elucidate the underlying mechanisms. Vehicle or trazodone (5, 10, and 20 mg/kg/day) was administered to rats for 28 consecutive days (n = 8 per group). At the end of that period, sperm concentration, motility, morphology, and DNA damage were determined and testicular morphology was assessed histopathologically in rats. Additionally, we investigated hormonal status by determining serum testosterone, FSH, and LH levels and oxidative stress by determining glutathione and malondialdehyde levels in testicular tissue to elucidate mechanisms of possible reproductive toxicity. According to our results, sperm concentration, sperm motility, and normal sperm morphology were decreased; sperm DNA damage was increased in trazodone-administered groups. Degenerative findings on the testicular structure were observed after trazodone administration in rats. Additionally, serum FSH, LH, and testosterone levels were elevated in the trazodone-administered groups. Increased MDA levels were the signs of enhanced oxidative stress after trazodone administration in testis tissues. Thus, we concluded that trazodone induced reproductive toxicity in male rats; this reproductive toxicity was accompanied by oxidative stress and hormonal changes, which are considered as important causes of reproductive disorders.

Mitochondrial protein Fus1/Tusc2 in premature aging and age-related pathologies: critical roles of calcium and energy homeostasis

Decreased energy production and increased oxidative stress are considered to be major contributors to aging and aging-associated pathologies. The role of mitochondrial calcium homeostasis has also been highlighted as an important factor affecting different pathological conditions. Here, we present evidence that loss of a small mitochondrial protein Fus1 that maintains mitochondrial homeostasis results in premature aging, aging-associated pathologies, and decreased survival. We showed that Fus1KO mice develop multiple early aging signs including lordokyphosis, lack of vigor, inability to accumulate fat, reduced ability to tolerate stress, and premature death. Other prominent pathological changes included low sperm counts, compromised ability of adult stem cells to repopulate tissues, and chronic inflammation. At the molecular level, we demonstrated that mitochondria of Fus1 KO cells have low reserve respiratory capacity (the ability to produce extra energy during sudden energy demanding situations), and show significantly altered dynamics of cellular calcium response.

Our recent studies on early hearing and memory loss in Fus1 KO mice combined with the new data presented here suggest that calcium and energy homeostasis controlled by Fus1 may be at the core of its aging-regulating activities. Thus, Fus1 protein and Fus1-dependent pathways and processes may represent new tools and targets for anti-aging strategies.

Citalopram Induces Reproductive Toxicity in Male Rats

BACKGROUND

Citalopram hydrobromide (CTL) has been shown to cause sexual dysfunction; however, its reproductive toxicity potential has not been sufficiently elucidated in men. Therefore, we aimed to clarify the toxic effects of CTL on the reproductive system of male rats.

METHODS

For this purpose, CTL was administered at 5, 10, and 20 mg/kg/day to rats orally for 28 days. Sperm concentration, motility, and morphology were investigated using a computer-assisted sperm analysis system, and sperm DNA damage was detected using a Comet assay. The testes were histopathologically examined. Serum follicle-stimulating hormone, luteinizing hormone, and testosterone levels were measured and the oxidative status of testes was investigated.

RESULTS

Our results showed that sperm concentration was reduced, and abnormal sperm morphology and sperm DNA damage were increased in CTL-administered groups. Additionally, histopathological changes were observed in the testes of CTL-administered rats. Luteinizing hormone levels were increased in CTL-administered groups, while testosterone levels were increased in the 5 and 10 mg/kg CTL-administered groups. Decreased glutathione signaled enhanced oxidative stress in the 10 and 20 mg/kg CTL-administered groups.

CONCLUSION

Thus, we concluded that CT induced testicular damage in male rats; this testicular damage was accompanied by oxidative stress and hormonal changes, which are considered as the important causes of reproductive disorders. Birth Defects Research 109:475-485, 2017. © 2017 Wiley Periodicals, Inc.

The Disappearing Sperms: Analysis of Reports Published Between 1980 and 2015

Reports regarding the changes in sperm concentration in different counties of the world are inconsistent. Furthermore, the reports that sprung up from specific epidemiological and experimental examinations did not include data of prior studies or geographical variations. The current study, following a previous report of massive fall in semen volume over the past 33 years, attempts to delineate the trend of altering sperm concentrations and factors responsible for this by reviewing article published from 1980 to July 2015 with geographic differences. The current study identified an overall 57% diminution in mean sperm concentration over the past 35 years ( r = -.313, p = .0002), which, when analyzed for each geographical region, identified a significant decline in North America, Europe, Asia, and Africa. An increasing trend of sperm concentration was identified only in Australia. The association of male age with such a trend ( R² = .979) is reported. The authors also correlated male fertility with sperm concentration. Thus, this comprehensive, evidence-based literature review aims to concisely and systematically present the available data on sperm concentration from 1980 to 2015, as well as to statistically analyze the same and correlate male health with the declining pattern of sperm count in a single scientific review to serve the scientific research zone related to reproductive health. It points to the threat of male infertility in times ahead.

Effects of aging on the male reproductive system

The study aims to discuss the effects of aging on the male reproductive system. A systematic review was performed using PubMed from 1980 to 2014. Aging is a natural process comprising of irreversible changes due to a myriad of endogenous and environmental factors at the level of all organs and systems. In modern life, as more couples choose to postpone having a child due to various socioeconomic reasons, research for understanding the effects of aging on the reproductive system has gained an increased importance. Paternal aging also causes genetic and epigenetic changes in spermatozoa, which impair male reproductive functions through their adverse effects on sperm quality and count as, well as, on sexual organs and the hypothalamic-pituitary-gonadal axis. Hormone production, spermatogenesis, and testes undergo changes as a man ages. These small changes lead to decrease in both the quality and quantity of spermatozoa. The offspring of older fathers show high prevalence of genetic abnormalities, childhood cancers, and several neuropsychiatric disorders. In addition, the latest advances in assisted reproductive techniques give older men a chance to have a child even with poor semen parameters. Further studies should investigate the onset of gonadal senesce and its effects on aging men.

Consistent age-dependent declines in human semen quality: a systematic review and meta-analysis

Reduced fertility typically occurs among women in their late 30s, but increasing evidence indicates that advanced paternal age is associated with changes in reproduction as well. Numerous studies have investigated age-based declines in semen traits, but the impact of paternal age on semen parameter values remains inconclusive. Using data from 90 studies (93,839 subjects), we conducted a systematic review and meta-analysis to quantify the effect of male age on seven ejaculate traits (semen volume, sperm concentration, total sperm count, morphology, total motility, progressive motility and DNA fragmentation). Age-associated declines in semen volume, percentage motility, progressive motility, normal morphology and unfragmented cells were statistically significant and results generally seemed to be robust against confounding factors. Unexpectedly, sperm concentration did not decline with increasing male age, even though we found that sperm concentration declined over time. Our findings indicate that male age needs more recognition as a potential contributor to the negative pregnancy outcomes and reduced offspring health associated with delayed first reproduction. We suggest that greater focus on collection of DNA fragmentation and progressive motility in a clinical setting may lead to better patient outcomes during fertility treatments of aging couples.

SirT1 is required in the male germ cell for differentiation and fecundity in mice

Sirtuins are NAD(+)-dependent deacylases that regulate numerous biological processes in response to the environment. SirT1 is the mammalian ortholog of yeast Sir2, and is involved in many metabolic pathways in somatic tissues. Whole body deletion of SirT1 alters reproductive function in oocytes and the testes, in part caused by defects in central neuro-endocrine control. To study the function of SirT1 specifically in the male germ line, we deleted this sirtuin in male germ cells and found that mutant mice had smaller testes, a delay in differentiation of pre-meiotic germ cells, decreased spermatozoa number, an increased proportion of abnormal spermatozoa and reduced fertility. At the molecular level, mutants do not have the characteristic increase in acetylation of histone H4 at residues K5, K8 and K12 during spermiogenesis and demonstrate corresponding defects in the histone to protamine transition. Our findings thus reveal a germ cell-autonomous role of SirT1 in spermatogenesis.

Age thresholds for changes in semen parameters in men

OBJECTIVE

To determine whether age thresholds for elements of semen quality exist.

DESIGN

Retrospective analysis (covariance and point-change analysis) of results of 4,822 semen analyses and 259 fluorescence in situ hybridization (FISH) analyses.

SETTING

Reference laboratory within an infertility clinic.

PATIENT(S)

A total of 5,081 men aged 16.5-72.3 years.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Ejaculate volume, sperm concentration, sperm motility, sperm motion parameters, strict morphology, and results of FISH analysis.

RESULT(S)

Measured parameters of ejaculates did not change before 34 years of age. Immediately thereafter, total sperm numbers (and total motile) declined. Sperm concentration and the proportion of sperm of normal morphology declined after 40 years. Sperm motility and progressive parameters of motile sperm fell after 43 years and ejaculate volume after 45 years. The ratio of Y:X-bearing sperm in ejaculates decreased only after 55 years.

CONCLUSION(S)

Our findings project a declining likelihood of pregnancy following intercourse with men >34 years old, independent from the woman's age and increasing with advancing age. Age-related mechanisms associated with this oligoasthenoteratozoospermic progression are discussed.

Reproductive function in middle-aged males: healthy men versus male partners of infertile couples

The aim of this study was to compare the reproductive parameters and the health-related, lifestyle and educational factors in middle-aged healthy men and male partners of infertile couples. Our patient group included 164 male partners of infertile couples with a preceding period of infertility of at least 12 months and 61 men attending a prostate health screening and considering themselves healthy. Significant differences between the groups were found in testicular volume, total sperm output, density and morphology as well as oestradiol levels in serum. The analysis showed significant positive correlations between testicular volume and semen quality, while negative correlations were observed between gonadotrophin levels and sperm parameters in both groups. Physical activity and sexual capability were higher in healthy men, while coital frequency and a history of sexually transmitted diseases were higher in male partners of infertile couples. The impact of physical activity and sexual capability on semen quality for all subjects was revealed. We can conclude that impaired reproductive function, that is, semen quality, in men >45 years is related not only with general male ageing but obvious differences between subjects of infertile couples and healthy middle-aged men can be seen. Their relations with lifestyle, environmental or physiological factors need further study.

Sex hormones and cause-specific mortality in the male veterans: the Vietnam Experience Study

BACKGROUND

Testosterone levels have been linked to life expectancy in men, less is known about the sex hormones follicular stimulating hormone and luteinizing hormone.

AIM

To examine the association of testosterone, follicular stimulating hormone, luteinizing hormone with mortality.

DESIGN

Prospective cohort analysis.

METHODS

Participants were 4255 Vietnam-era US army veterans with a mean age of 38.3 years. From military service files, telephone interviews and a medical examination, socio-demographic and health data were collected. Contemporary morning fasted hormone concentrations were determined. All-cause, cardiovascular, cancer, external and 'other' cause mortality was ascertained over the subsequent 15 years. Hazard ratios were calculated, first with adjustment for age and then, additionally, for a range of confounders.

RESULTS

Individuals within the highest tertiles of follicle stimulating hormone (FSH) and luteinizing hormone (LH) levels were at increased risk of all-cause mortality following adjustment for a range of risk factors. However, with mutual adjustment, neither FSH nor LH significantly predicted mortality. Testosterone levels did not show an association with all-cause mortality, and none of the hormones were significantly associated with CVD, cancer, 'other' or external-cause mortality in fully adjusted models.

CONCLUSION

Greater FSH and LH levels are associated with all-cause mortality, but not independently of one another.

Aging of the human ovary and testis

Aging is associated with structural and functional alterations in all organs of the human body. The aging of gonads represents in this respect a special case, because these organs are not functional for the whole lifespan of an individual and their normal function is not indispensable for functions of the rest of the body. Ovarian function lasts for the reproductive life of a woman, i.e., from menarche until menopause. The testicular endocrine function, in contrast, begins already in utero, is interrupted between neonatal life and puberty, and continues thereafter along with spermatogenesis, with only slight decline, until old age. The aging processes of the ovary and testis are therefore very different. We describe in this review the structural and functional alterations in the human ovary and testis upon aging. Special emphasis will be given to clinically significant alterations, which in women concern the causes and consequences of the individual variability of fertility during the latter part of the reproductive age. The clinically important aspect of testicular aging entails the decline of androgen production in aging men.

The male biological clock is ticking: a review of the literature

The term biological clock is usually used by physicians and psychologists to refer to the declining fertility, increasing risk of fetal birth defects and alterations to hormone levels experienced by women as they age. Female fecundity declines slowly after the age of 30 years and more rapidly after 40 and is considered the main limiting factor in treating infertility. However, there are several scientific reports, chapters in books and review articles suggesting that men may also have a biological clock. The aim of our study was to conduct a review of the literature, based on the Medical Literature Analysis and Retrieval System Online (Medline), to evaluate the male biological clock. After adjustments for other factors, the data demonstrate that the likelihood that a fertile couple will take more than 12 months to conceive nearly doubles from 8% when the man is < 25 years old to 15% when he is > 35 years old. Thus, paternal age is a further factor to be taken into account when deciding on the prognosis for infertile couples. Also, increasing male age is associated with a significant decline in fertility (five times longer to achieve pregnancy at the age of 45 years). Patients and their physicians therefore need to understand the effects of the male biological clock on sexual and reproductive health, in that it leads to erectile dysfunction and male infertility, as well as its potential implications for important medical conditions such as diabetes and cardiovascular diseases.

Potential factors affecting semen quality in the Asian elephant (Elephas maximus)

BACKGROUND

One of the major obstacles in using artificial insemination to manage genetics of elephant population in captivity is the large variations in semen quality among ejaculates within the same and among individuals. The objectives of this study were to determine the influences of (1) age (2) seasonality (3) and circulating testosterone (SrTest), triiodothyronine (SrT3) and tetraiodothyronine (SrT4), as well as seminal (4) testosterone (SpTest), zinc (SpZn) and protein (SpTP) on semen quality in the Asian elephant

METHODS

Analyses, including motility, viability and morphology were performed in semen samples collected twice monthly from 13 elephant bulls (age range, 10-to 72-years) by manual stimulation between July 2004 and June 2005. Serum samples obtained monthly were assessed for SrTest, SrT3, SrT4, and seminal plasma samples were evaluated for, SpTest, SpZn and SpTP.

RESULTS

The highest semen quality was observed at age 23 to 43 years. Percentages of progressive motility and viable sperm were lowest at age 51 to 70 years (P < 0.05); on the other hand, sperm concentration was lowest at age 10 to 19 years (P < 0.05). Percentage of sperm with normal morphology was highest at age 23 to 43 years. The levels of SrT3, SrTest, SpTest and SpZn were lowest at age 51 to 70 years, whereas SrT4 was lowest at age 23 to 43 years. Seasonality significantly affected semen characteristics in which percentage of viable sperm and cell concentration were highest during rainy season and lowest during summer months (P < 0.05). However, percentage of sperm with normal morphology was highest in summer and lowest in rainy season (P < 0.05). Seasonality significantly influenced SrTest with elevated concentrations observed in rainy season and winter (P < 0.05).

CONCLUSION

This study indicates that age and seasonality had influence on semen characteristics in the Asian elephant. The knowledge obtained in this study will improve our understanding of the reproductive biology of this species.

The value of canine semen evaluation for practitioners

Compared to human medicine, little is known in canine medicine regarding specific findings on semen evaluation and their correlation with fertility. Suggestions to optimize quality of semen evaluation in veterinary practice include creating standardized protocols for evaluation of all semen parameters and updating those protocols as needed; creating some form of quality control for the clinic laboratory; educating owners about our inability to predict with 100% accuracy whether dogs with poor semen quality never could impregnate a bitch or whether dogs with excellent semen quality always could impregnate a bitch; and generating protocols for further diagnostic work-up for those dogs with abnormal semen quality.

Orchidopexy and its impact on fertility

We critically analysed the factors known to influence the fertility potential after orchidopexy in children. A comprehensive literature review of all publications in the English language listed in Medline using the words cryptorchidism, undescended testis, orchidopexy, fertility, semen analysis and surgery from 1970 to 2005. In unilateral ectopic, canalicular and emergent testes, as long as the surgery is carried out in early childhood, fertility outcome is good (>90%). The majority of the bilateral abdominal testes are infertile. While unilateral abdominal testes and unilateral absent or vanishing testes have favourable fertility potential, quantification has proven difficult. Despite multiple studies, fertility in crypt orchid tests is still an uncertain issue. Hormonal treatment in conjunction with early surgical correction has not been fully explored. We recommend orchidopexy soon after 6-7 months of age, corrected for term, to maximise the future fertility potential.

Age-Related Structural and Metabolic Changes in the Pelvic Reproductive End Organs

In this work, we provide preliminary data and a review of the literature regarding normal structural and functional changes that occur in the aging uterus, ovary, testicle, and prostate gland. It is expected that such knowledge will help physicians to distinguish physiologic changes from pathologic changes at an early stage. We retrospectively reviewed pelvic magnetic resonance imaging (MRI) scans of 131 female and 79 male subjects ages 13 to 86 years to determine changes in volume of the uterus, ovary, and prostate gland with age. Scrotal ultrasound examinations of 150 male subjects ages 0 to 96 years also were analyzed retrospectively to determine changes in testicular volume with age. In addition, (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET) scans of 145 male subjects ages 11 to 90 years were analyzed retrospectively to assess for changes in maximum standardized uptake value (SUV(max)) of the testicles with age. The uterus had a mean volume of 38.55 +/- 3.68 cm(3) at 17 to 19 years of age, increased to a peak volume of 71.76 +/- 19.81 cm(3) between 35 to 40 years, and then declined to 24.02 +/- 8.11 cm(3) by the eighth decade of life. The maximal ovarian volume per subject maintained a relatively stable size in early life, measuring 9.46 +/- 3.25 cm(3) during the second decade of life, 8.46 +/- 3.32 cm(3) in the mid-fourth decade of life, and 7.46 +/- 3.33 cm(3) at 45 years of age, after which it declined to 4.44 +/- 2.02 cm(3) by the late fifth decade of life. The ovaries were not identifiable on MRI in subjects beyond the sixth decade of life. The volume of the prostate increased from 23.45 +/- 6.20 cm(3) during the second decade of life to 47.5 +/- 41.59 cm(3) by the late eighth decade of life; the central gland of the prostate increased from 9.96 +/- 3.99 cm(3) to 29.49 +/- 28.88 cm(3) during the same age range. Mean testicular volume was 11.2 +/- 5.9 cm(3). Testicular volume increased with age from birth to 25 years. After age 25, there was a significant decline in the testicular volume. The mean SUV(max) for the testicles was 1.9 +/- 0.5. Testicular metabolic activity demonstrated an increasing trend until the age of 35 years. A plateau in SUV(max) was observed after the age of 35 years until the age of 65 years. A slight decrease in SUV(max) was observed after the age of 65 years. The pelvic structures of men and women change both structurally and functionally over the lifespan, and such changes can be quantified using ultrasound, MRI, and (18)F-FDG-PET.

Aging does not affect spermatogenic recovery after experimentally induced injury in mice

Testes in aging mammals undergo a variety of age-related changes, such as reduction of size, lower sperm output, an increase in abnormal forms of sperm, and endocrine malfunctions. It has been suggested that the spermatogenic defects are due to loss and dysfunction of spermatogonial stem cells as well as deterioration of the tubule microenvironment. In the present study, we explore the depletion and recovery of spermatogenesis in young (3 month) and old (12 month) mice exposed to cooling, X-irradiation (5 Gy) or cytotoxic treatment using Busulfan (40 mg/kg). We aim to determine a potential age-related change of vulnerability to gonadotoxic treatments by describing the intensity of spermatogenic depletion and the degree of spermatogenic recolonization with qualitative and quantitative parameters on organ weights and histological parameters at two time points (2 weeks, depletion; 6 weeks, recovery). Our data reveal specific acute effects of cooling on multinucleation of germ cells but no other severe injury. Irradiation and Busulfan-treatment exerted the expected depletional wave of germ cells leading to severe testicular injury and spermatogenic failure. The recovery of spermatogenesis occurred in both treatment groups and both age groups to a similar extent. We therefore noted no prominent age-related differences in spermatogenic depletion and recovery in any treatment group. We conclude that in both age groups, the remaining spermatogonial stem cells are capable to induce spermatogenic recovery and the aging tubule microenvironment at 1 year has not become more vulnerable to irradiation, Busulfan-treatment or testicular cooling.

Age-related patterns of urinary gonadotropins (FSH and LH) and E-3-G as measures of reproductive function among Turkana males of northern Kenya

To determine age-related patterns of gonadotropins and their relationship to energetic status in a subsistence population we analyzed urinary FSH, LH, and estrone-3-glucuronide (E-3-G) along with anthropometric measures among Turkana males of northern Kenya. Subjects were 134 nomadic and 109 settled males ages 20 to 80+. FSH, LH and E-3-G were significantly higher among the settled, compared to nomadic, males. LH, but not FSH, showed a significant increase across 10 year age groups among all the men. E-3-G increased across age groups only among the settled males. Controlled for age, FSH was inversely related to measures of fat free and body mass among the settled men. These findings suggest an unusual age profile of gonadotropins and estrogen metabolites that may reflect the impact of fluctuating food availability. More research is needed to address the impact of energetic and social factors on the male reproductive axis among energetically stressed populations.