Vitamin D and male reproduction

An association weight matrix identified biological pathways associated with bull fertility traits in a multi-breed population

Using seven indicator traits, we investigated the genetic basis of bull fertility and predicted gene interactions from SNP associations. We used percent normal sperm as the key phenotype for the association weight matrix-partial correlation information theory (AWM-PCIT) approach. Beyond a simple list of candidate genes, AWM-PCIT predicts significant gene interactions and associations for the selected traits. These interactions formed a network of 537 genes: 38 genes were transcription cofactors, and 41 genes were transcription factors. The network displayed two distinct clusters, one with 294 genes and another with 243 genes. The network is enriched in fertility-associated pathways: steroid biosynthesis, p53 signalling, and the pentose phosphate pathway. Enrichment analysis also highlighted gene ontology terms associated with 'regulation of neurotransmitter secretion' and 'chromatin formation'. Our network recapitulates some genes previously implicated in another network built with lower-density genotypes. Sequence-level data also highlights additional candidate genes relevant to bull fertility, such as FOXO4, FOXP3, GATA1, CYP27B1, and EBP. A trio of regulatory genes-KDM5C, LRRK2, and PME-was deemed core to the network because of their overarching connections. This trio probably influences bull fertility through their interaction with genes, both known and unknown as to their role in male fertility. Future studies may target the trio and their target genes to enrich our understanding of male fertility further.

Effects of Simulated Microgravity on Rat Reproductive System: Potential Benefits of Vitamin D3 Intervention

Gravity in space can have a negative impact on the reproductive system. Given that the reproductive system is one of vitamin D's objectives, this study will use a simulated microgravity model to evaluate its impact on the rat reproductive system.Twenty-two male Wistar rats were allocated into four groups at random. Under microgravity circumstances, the rats were housed in both special and standard cages. Each group was then separated into two subgroups, one of which received vitamin D3 and the other did not. Blood was drawn twice to determine blood levels of vitamin D3, LH, FSH, and testosterone. Rat testes were isolated for histological analysis, as well as a piece of epididymis for sperm count and morphological examination.Microgravity had a detrimental effect on testicular tissue, resulting in lower serum levels of LH and testosterone (p-value < 0.001). Spermatogenesis was largely inhibited under microgravity. During microgravity conditions, however, vitamin D3 had a good effect on testicular structure, and the total number of sperm. Simulated microgravity affects the male reproductive system, compromising testicular morphology, sperm parameters, and hormonal balance. However, this study shows that vitamin D3 supplementation can act as a preventative strategy, minimizing the negative consequences of microgravity. The beneficial effect of vitamin D3 on testicular health and sperm quality implies that it may be useful in protecting male reproductive function in space-related situations.

Causal association between 25-Hydroxyvitamin D and risk of abnormal spermatozoa: A bidirectional Mendelian randomization study

Previous studies indicated conflicting findings regarding the association between vitamin D and abnormal spermatozoa. Herein, we assessed the causal association between circulating 25-Hydroxyvitamin D (25OHD) levels and the risk of abnormal spermatozoa by utilizing bidirectional Mendelian randomization (MR) analysis. Genome-wide association study summary statistics for 25OHD and abnormal spermatozoa were obtained from publicly accessible databases. Single nucleotide polymorphisms (SNPs) associated with 25OHD and SNPs associated with abnormal spermatozoa were used as instrumental variables (IVs) for forward MR analysis and reverse MR analysis, respectively. Inverse variance weighted (IVW) was the main MR approach, while weighted median, MR-Egger, and maximum likelihood methods were employed to supplement IVW. In addition, several sensitivity tests assessed the reliability of MR analysis. Forward MR analysis showed that elevated 25OHD levels significantly reduced abnormal spermatozoa risk (odds ratio [OR] = 0.75, 95 % confidence interval [CI]: 0.56-1.00, P = 4.98E-02), and the effect remained statistically significant after excluding SNPs associated with confounders (OR = 0.73, 95 % CI: 0.54-0.98, P = 3.83E-02) or only utilizing SNPs located near 25OHD-associated genes only as IVs (OR = 0.58, 95 % CI: 0.41-0.81, P = 1.67E-03). Reverse MR analysis indicated abnormal spermatozoa not affecting 25OHD level (P > 0.05). Sensitivity tests showed that MR analyses were not affected by heterogeneity and horizontal polytropy. Overall, the present MR study supports that elevated 25OHD levels reduce the risk of abnormal spermatozoa. Therefore, ensuring adequate vitamin D intake and maintaining stable levels of 25OHD may be effective strategies to optimize reproductive outcomes.

Injection of luteinizing hormone or human chorionic gonadotropin increases calcium excretion and serum PTH in males

Animal and human studies have suggested that sex steroids have calciotropic actions, and it has been proposed that follicle-stimulating hormone (FSH) may exert direct effects on bone. Here, we demonstrate the expression of the receptor for Luteinizing hormone (LH) and human choriogonadotropin (hCG), LHCGR, in human kidney tissue, suggesting a potential influence on calcium homeostasis. To investigate the role of LHCGR agonist on calcium homeostasis in vivo, we conducted studies in male mice and human subjects. Male mice were treated with luteinizing hormone (LH), and human extrapolation was achieved by injecting 5000 IU hCG once to healthy men or men with hypergonadotropic or hypogonadotropic hypogonadism. In mice, LH treatment significantly increased urinary calcium excretion and induced a secondary increase in serum parathyroid hormone (PTH). Similarly, hCG treatment in healthy men led to a significant increase in urinary calcium excretion, serum PTH levels, and 1,25 (OH)2D3, while calcitonin, and albumin levels were reduced, possibly to avoid development of persistent hypocalcemia. Still, the rapid initial decline in ionized calcium coincided with a significant prolongation of the cardiac QTc-interval that normalized over time. The observed effects may be attributed to LH/hCG-receptor (LHCGR) activation, considering the presence of LHCGR expression in human kidney tissue, and the increase in sex steroids occurred several hours after the changes in calcium homeostasis. Our translational study shed light on the intricate relationship between gonadotropins, sex hormones and calcium, suggesting that LHCGR may be influencing calcium homeostasis directly or indirectly.

Calcium and vitamin D homoeostasis in male fertility

Calcium and vitamin D have well-established roles in maintaining calcium balance and bone health. Decades of research in human subjects and animals have revealed that calcium and vitamin D also have effects on many other organs including male reproductive organs. The presence of calcium-sensing receptor, vitamin D receptor, vitamin D activating and inactivating enzymes and calcium channels in the testes, male reproductive tract and human spermatozoa suggests that vitamin D and calcium may modify male reproductive function. Functional animal models have shown that vitamin D deficiency in male rodents leads to a decrease in successful mating and fewer pregnancies, often caused by impaired sperm motility and poor sperm morphology. Human studies have to a lesser extent validated these findings; however, newer studies suggest a positive effect of vitamin D supplementation on semen quality in cases with vitamin D deficiency, which highlights the need for initiatives to prevent vitamin D deficiency. Calcium channels in male reproductive organs and spermatozoa contribute to the regulation of sperm motility and capacitation, both essential for successful fertilisation, which supports a need to avoid calcium deficiency. Studies have demonstrated that vitamin D, as a regulator of calcium homoeostasis, influences calcium influx in the testis and spermatozoa. Emerging evidence suggests a potential link between vitamin D deficiency and male infertility, although further investigation is needed to establish a definitive causal relationship. Understanding the interplay between vitamin D, calcium and male reproductive health may open new avenues for improving fertility outcomes in men.

VDRA downregulate β-catenin/Smad3 and DNA damage and repair associated with improved prognosis in ccRCC patients

The clear cell renal cell carcinoma (ccRCC) spotlighted the poorest survival, while chromophobe renal cell carcinoma (chRCC) was associated with the best survival. Earlier studies corroborated vitamin D receptor (VDR) was a promising molecular for improving the prognosis of RCC. In contrast to VDRA, the one of VDR isoforms, VDRB1 (VDR isoform B1) has an N-terminal extension of 50 amino acids and is less ligand-dependent. However, the functional differences between VDRA and VDRB1, and their roles in the prognosis of ccRCC and chRCC, have not been investigated. In the present study, we uncovered that the transcripts related to vitamin D pathway and cellular calcium signaling were effectively decreased in the context of ccRCC, yet failed to exert a comparable effect within chRCC. Specially, minimally levels of VDRA wherein kidneys of patients suffering from ccRCC predict shorter survival time. In addition, the protein expressions for β-catenin/Smad3 pathway and DNA damage and repair pathways were obviously impeded in VDRA-overexpressed ccRCC cells, yet this inhibitory effect was conspicuously absent in enable VDRB1 cells. Our results provide a new idea to improve the prognosis of ccRCC via VDRA upregulation.

Relationship between vitamin D receptors gene polymorphism and arteriogenic erectile dysfunction

BACKGROUND

Over the past few decades, a number of studies have linked vitamin-D deficiency with ED (Erectile dysfunction) risk factors. There is a clear correlation between VD (vitamin-D) levels and ED, according to observational and interventional researches that have been reported in the literature. This crucial information encouraged scientists to investigate the impact of VD on erectile function in greater detail. The fact that vitamin D is a component of a healthy penis that begins in early life has just come to light, however there haven't been many research looking at the connection between vitamin D receptor gene polymorphism and erectile dysfunction.

OBJECTIVE

To evaluate the relationship between arteriogenic erectile dysfunction and the vitamin D receptor gene polymorphism.

SUBJECTS AND METHODS

Between October 2022 and October 2023, at Al-Azhar University Hospitals, 40 patients with arteriogenic ED and 40 healthy controls underwent informed consent, a detailed history, a physical examination, a penile duplex ultrasound and the extraction of peripheral blood to determine the type of polymorphism for each of the vitamin D receptors: FokI, BsmI, ApaI and TaqI by polymerase chain reaction (PCR).

RESULTS

There is no statistically significant association between arteriogenic erectile dysfunction and the vitamin D receptors (VDR) gene polymorphisms FokI, BsmI, ApaI and TaqI.

CONCLUSION

Since there is no statistically significant association between the polymorphism of the vitamin D receptor (VDR) gene and arteriogenic erectile dysfunction, it is advised to investigate other VDR gene polymorphisms as well as alternative clinical subtypes of erectile dysfunction.

Effects of vitamin D on sex steroids, luteinizing hormone, and testosterone to luteinizing hormone ratio in 307 infertile men

OBJECTIVE

Vitamin D status has been associated with sex steroid production. The question is whether vitamin D supplementation has an impact on sex steroid production in infertile men with vitamin D insufficiency?

DESIGN

A single-center, double-blinded, randomized clinical trial. Differences in sex steroids and reproductive hormones were predefined secondary outcomes, vitamin D status at baseline was a predefined subgroup and the primary outcome was differences in semen quality.

METHODS

A total of 307 infertile men were included and randomized 1:1 to active or placebo treatment for 150 days. Men in the active group initially received an oral bolus of 300,000 IU cholecalciferol, followed by daily supplementation with 1400 IU cholecalciferol and 500 mg calcium.

RESULTS

After intervention, no differences were found in serum concentrations of sex steroids, luteinizing hormone, testosterone/luteinizing hormone ratio or SHBG between the vitamin D and placebo group. However, in a predefined subgroup analysis of men with serum 25OHD ≤ 50 nmol/L, men treated with vitamin D had a significantly higher testosterone/luteinizing hormone ratio [4.2 (3.8-4.4) vs. 3.7 (3.4-4.0); p = 0.033] compared with placebo treatment. In men with vitamin D deficiency, the difference between groups was larger but not significant due to few men with serum 25OHD < 25 nmol/L.

CONCLUSION

Vitamin D + calcium supplementation did not alter sex steroid production in infertile men. However, vitamin D insufficient men treated with vitamin D supplementation had a significantly higher testosterone/LH ratio compared with placebo-treated men, suggesting that optimal Leydig cell function are dependent on adequate vitamin D status.

Influence of the Mediterranean diet on seminal quality-a systematic review

Currently, there is a growing interest in the study of fertility because fertility-related problems affect up to 15% of the world's population. The aim of this study was to determine the influence of the Mediterranean diet on seminal quality in men of reproductive age. For this purpose, a systematic review of the literature was carried out following the PRISMA method. Electronic searches were carried out in the international databases PubMed, Scopus, the Cochrane Library, and Web of Science. In total, 10 articles with 2032 men were included. As inclusion criteria, articles published between 2012 and 2022 were selected, including those that included men aged between 18 and 55 years. Nutritional status was assessed through weight, height, and BMI. Dietary habits were evaluated through different indexes and food frequency questionnaires, and finally, semen quality was evaluated by measuring sperm concentration and motility (progressive and non-progressive). In six (60%) of the included articles, a positive relationship between adherence to the Mediterranean diet and semen quality was demonstrated; in two (20%) of the articles, no association was found; and finally, in two (20%) of the included articles, the relationship between dietary patterns typical of DM and semen quality was evaluated. Dietary habits influence semen quality. Adherence to the Mediterranean diet can improve male reproductive health, as it is a diet with antioxidant and anti-inflammatory effects. This is the first systematic review about the influence of the Mediterranean diet on semen quality, and the results are positive. These findings may allow us to provide better advice to our patients and to establish interventions with the aim of improving the results of assisted reproduction techniques.

High-dose vitamin D3 supplementation shows no beneficial effects on white blood cell counts, acute phase reactants, or frequency of respiratory infections

BACKGROUND

Vitamin D has been suggested to influence the immune system, and vitamin D metabolites and the vitamin D receptor (VDR) are generated and expressed in white blood cells (WBC). Moreover, vitamin D status has been associated with incidence and prognosis of some respiratory tract infections (RTI). Therefore, we investigated the effect of vitamin D3 supplementation on WBC, acute phase reactants (APR), and the risk of developing RTIs.

METHODS

A double-blinded, randomized, placebo-controlled clinical trial of 307 infertile men with multiple secondary immunological endpoints. The vitamin D3 group (n = 151) initially received 300,000 IU (7,500 µg) cholecalciferol once - followed by 1,400 IU (35 µg) daily for 150 days. The placebo group (n = 156) did not receive active ingredients.

RESULTS

At baseline, stratification into clinically relevant groups of vitamin D status (< 25; 25-50; 50-75; >75 nmol/L), showed an inverse association with total leucocyte concentrations (7.0 vs. 6.0 vs. 6.0 vs. 5.5 (109/L); p = 0.007), lymphocytes (2.4 vs. 2.1 vs. 2.0 vs. 2.0 (109/L); p = 0.048), CRP (2.0 vs. 1.7 vs. 1.2 vs. 1.2 (mg/L); p = 0.037), and orosomucoid (0.82 vs. 0.77 vs. 0.76 vs. 0.70 (g/L); p = 0.015). After 150 days, no differences were detected in WBC counts or APRs between the vitamin D3 and the placebo group. However, vitamin D3 treated men had a higher prevalence of self-reported RTIs compared with the placebo group (55% vs. 39%; p = 0.005).

CONCLUSIONS

High-dose vitamin D3 supplementation did not alter WBCs or APRs, but a higher prevalence of respiratory infections was observed in the vitamin D3 group. Serum 25(OH)D3 was negatively correlated with most WBCs, indicating that vitamin D status may be linked with inflammation and WBC turnover, but not an important determinant of developing RTIs.

TRIAL REGISTRATION

NCT01304927 (ClinicalTrials.gov). Registered February 20, 2011.

Sarcopenia and Diabetes: A Detrimental Liaison of Advancing Age

Sarcopenia is an age-related clinical complaint characterized by the progressive deterioration of skeletal muscle mass and strength over time. Type 2 diabetes (T2D) is associated with faster and more relevant skeletal muscle impairment. Both conditions influence each other, leading to negative consequences on glycemic control, cardiovascular risk, general health status, risk of falls, frailty, overall quality of life, and mortality. PubMed/Medline, Scopus, Web of Science, and Google Scholar were searched for research articles, scientific reports, observational studies, clinical trials, narrative and systematic reviews, and meta-analyses to review the evidence on the pathophysiology of di-abetes-induced sarcopenia, its relevance in terms of glucose control and diabetes-related outcomes, and diagnostic and therapeutic challenges. The review comprehensively addresses key elements for the clinical definition and diagnostic criteria of sarcopenia, the pathophysiological correlation be-tween T2D, sarcopenia, and related outcomes, a critical review of the role of antihyperglycemic treatment on skeletal muscle health, and perspectives on the role of specific treatment targeting myokine signaling pathways involved in glucose control and the regulation of skeletal muscle metabolism and trophism. Prompt diagnosis and adequate management, including lifestyle inter-vention, health diet programs, micronutrient supplementation, physical exercise, and pharmaco-logical treatment, are needed to prevent or delay skeletal muscle deterioration in T2D.

Minipuberty in Sons of Women with Low Vitamin D Status during Pregnancy

Minipuberty is a transient phase of reproductive axis activation during the first several months of life, playing an important role in the development of reproductive organs in boys. Low 25-hydroxyvitamin D levels during pregnancy are associated with an increased risk of neonatal complications. An inadequate gestational vitamin D status is hypothesized to affect the postnatal activation of the hypothalamic-pituitary-gonadal axis. The purpose of our study was to assess whether a low vitamin D status during pregnancy determines the course of minipuberty in boys. The study included three groups of male infants born to women with different vitamin D statuses: sons of women with vitamin D deficiency (group 1), sons of women with vitamin D insufficiency (group 2), and male offspring of females with normal 25-hydroxyvitamin D levels (group 3 (the reference group)). Concentrations of testosterone, androstenedione, dehydroepiandrosterone sulfate, estradiol, progesterone, and 17-hydroxyprogesterone in saliva, as well as concentrations of gonadotropins in urine, were assayed monthly from postnatal months 1 to 6, and once every 2 months in the second half of the first year of life. Additionally, at each visit, penile length and testicular volume were assessed. Concentrations of testosterone, FSH, and LH, as well as penile length and testicular volume, were greater in group 1 than in groups 2 and 3. In turn, group 2 was characterized by higher FSH levels and a greater testicular volume than group 3. Peak concentrations of LH and testosterone were observed earlier in group 1 than in the remaining groups. The obtained results suggest that a low vitamin D status during pregnancy may have a stimulatory impact on reproductive axis activity and on the early postnatal development of male genital organs, correlating with the severity of hypovitaminosis D.

VDR promotes testosterone synthesis in mouse Leydig cells via regulation of cholesterol side chain cleavage cytochrome P450 (Cyp11a1) expression

BACKGROUND

The vitamin D receptor (VDR) mediates the pleiotropic biological actions that include osteoporosis, immune responses and androgen synthesis.VDR is widely expressed in testis cells such as Leydig cells, Sertoli cells, and sperm. The levels of steroids are critical for sexual development. In the early stage of steroidogenesis, cholesterol is converted to pregnenolone (precursor of most steroid hormones) by cholesterol side-chain lyase (CYP11A1), which eventually synthesizes the male hormone testosterone.

OBJECTIVE

This study aims to reveal how VDR regulates CYP11A1 expression and affects testosterone synthesis in murine Leydig cells.

METHODS

The levels of VDR, CYP11A1 were determined by quantitative real-time polymerase chain reaction (RT-qPCR) or western blot. Targeted relationship between VDR and Cyp11a1 was evaluated by dual-luciferase reporter assay. The levels of testosterone concentrations in cell culture media serum by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Phylogenetic and motif analysis showed that the Cyp11a1 family had sequence loss, which may have special biological functions during evolution. The results of promoter prediction showed that vitamin D response element (VDRE) existed in the upstream promoter region of murine Cyp11a1. Dual-luciferase assay confirmed that VDR could bind candidate VDREs in upstream region of Cyp11a1, and enhance gene expression. Tissue distribution and localizatio analysis showed that Cyp11a1 was mainly expressed in testis, and dominantly existed in murine Leydig cells. Furthermore, over-expression VDR and CYP11A1 significantly increased testosterone synthesis in mice Leydig cells.

CONCLUSIONS

Active vitamin D3 (VD3) and Vdr interference treatment showed that VD3/VDR had a positive regulatory effect on Cyp11a1 expression and testosterone secretion. VDR promotes testosterone synthesis in male mice by up-regulating Cyp11a1 expression, which played an important role for male reproduction.

Analysis of the risk factors in patients with unexplained recurrent spontaneous abortion

PROBLEM

We aimed to explore the risk factors in patients with unexplained recurrent spontaneous abortion (URSA) and to provide a basis for clinically targeted therapy.

METHOD OF STUDY

This case-control study comprised 202 patients with URSA treated at our hospital and 115 women in early pregnancy with a normal birth history during the same period. After procuring the data we conducted a multivariate logistic regression analysis of risk factors related to URSA.

RESULTS

Logistic regression analysis showed (i) that the number of spontaneous abortions (SAs; odds ratio [OR] = 492.123), the levels of autoantibodies (OR = 19.322) and tumor necrosis factor alpha (TNF-α; OR = 9.615), and the CT and TT genotypes of methylenetetrahydrofolate reductase (MTHFR) C677T (OR = 6.217 and 15.009, respectively) were risk factors for URSA and (ii) that 25-hydroxyvitamin D (25-(OH)D; OR = 0.919) was a protective factor. The most important risk factor was a history of one or more SAs, with the risk of pregnancy loss increasing 491.123-fold. Every unit increase in serum 25-(OH)D reduced the risk of SA by 8.1%.

CONCLUSIONS

The risk factors for URSA included the number of SAs, the levels of autoantibodies and TNF-α, and the MTHFR C677T T allele; 25-(OH)D was a protective factor. We recommend that women diagnosed with URSA receive intervention as soon as possible so as to actively reduce the incidence of recurrent SA.

Association Between Vitamin D Deficiency and Testosterone Levels in Adult Males: A Systematic Review

Vitamin D deficiency and its potential impact on testosterone levels have been subjects of scientific interest. This systematic review aims to evaluate the association between vitamin D deficiency and testosterone levels in adult males and examine the effects of vitamin D supplementation on testosterone. A comprehensive literature search was conducted in accordance with the PRISMA guidelines across PubMed, Google Scholar, and ScienceDirect. The inclusion criteria involved studies published in English between 2013 and 2023, which investigated the correlation between vitamin D and testosterone levels in adult males. The process of data extraction and synthesis encompassed various aspects, including study characteristics, participant demographics, measurement methods, and outcomes pertaining to the association. The initial search resulted in a pool of 354,235 articles. Through the application of relevant filters and the review of titles and abstracts, 48 articles were chosen for further assessment. Out of these, eight studies fulfilled the inclusion criteria and were ultimately incorporated into the final review. The included studies consisted of four cross-sectional studies, three randomized controlled trials (RCTs), and one analysis utilizing Mendelian randomization. The results showed heterogeneity among the studies, as some reported a positive correlation between vitamin D levels and testosterone, while others did not find a significant association. The effects of vitamin D supplementation on testosterone levels were inconclusive, with limited evidence of significant changes in total testosterone. However, potential influences on sex hormone-binding globulin and free testosterone levels were observed. To establish more definitive evidence regarding the impact of vitamin D on testosterone levels, there is a need for further well-designed, long-term RCTs that encompass diverse populations.

Nonionizing Electromagnetic Irradiations; Biological Interactions, Human Safety

Human is usually exposed to environmental radiation from natural and man-made sources. Therefore, it is important to investigate the effects of exposure to environmental radiation, partly related to understanding and protecting against the risk of exposure to environmental radiation with beneficial and adverse impacts on human life. The rapid development of technologies causes a dramatic enhancement of radiation in the human environment. In this study, we address the biological effects caused by different fractions of non-ionizing electromagnetic irradiation to humans and describe possible approaches for minimizing adverse health effects initiated by radiation. The main focus was on biological mechanisms initiated by irradiation and represented protection, and safety approaches to prevent health disorders.

Isochromosome 12p Formation Regulates Vitamin D Metabolism in Testicular Cancer

Isochromosome 12p (iChr12p) is typical in almost all invasive testicular cancers. Increased copy number of genes on 12p is associated with the development of a clinically manifest tumor; however, the causative genes have not yet been identified. Chromosome 12 harbors many genes involved in Vitamin D metabolism. RNAseq analysis of Vitamin D receptor (VDR) genes from the TCGA cohort revealed that clustering of VDR expression signatures could differentiate between pure seminomas and non-seminomatous germ cell tumors (NSGCT). Using TCGA mRNA expression of anabolic (CYP2R1, CYP27A1 and CYP27B1) and catabolic (CYP24A1) Vitamin D enzymes, positive (PTHLH, IFNG, and TNF) and negative (FGF23) feedback regulators could also clearly distinguish between pure seminomas and NSGCT. We hypothesize that the regulation of Vitamin D metabolism might be disturbed through iChr12p formation, influencing testicular carcinogenesis via increased FGF23 and PTHLH expression. While FGF23 represses CYP27B1 and activates catabolism of active hormone, increased PTHLH secretion can lead to hypercalcemia via inactivation of VDR. In conclusion, testicular cancer is associated with extensive modifications in intratesticular Vitamin D homeostasis. Further research is needed to clarify whether Vitamin D deficiency causes the formation of iChr12p and whether Vitamin D deficiency via iChr12p genomic aberration is involved in testicular carcinogenesis.

Maternal vitamin D levels and male reproductive health: a population-based follow-up study

Maternal vitamin D levels during pregnancy may be important for reproductive health in male offspring by regulating cell proliferation and differentiation during development. We conducted a follow-up study of 827 young men from the Fetal Programming of Semen Quality (FEPOS) cohort, nested in the Danish National Birth Cohort to investigate if maternal vitamin D levels were associated with measures of reproductive health in adult sons. These included semen characteristics, testes volume, and reproductive hormone levels and were analysed according to maternal vitamin D (25(OH)D3) levels during pregnancy. In addition, an instrumental variable analysis using seasonality in sun exposure as an instrument for maternal vitamin D levels was conducted. We found that sons of mothers with vitamin D levels < 25 nmol/L had 11% (95% CI - 19 to - 2) lower testes volume and a 1.4 (95% CI 1.0 to 1.9) times higher risk of having low testes volume (< 15 mL), in addition to 20% (95% CI - 40 to 9) lower total sperm count and a 1.6 (95% CI 0.9 to 2.9) times higher risk of having a low total sperm count (< 39 million) compared with sons of mothers with vitamin D levels > 75 nmol/L. Continuous models, spline plots and an instrumental variable analysis supported these findings. Low maternal vitamin D levels were associated with lower testes volume and lower total sperm count with indications of dose-dependency. Maternal vitamin D level above 75 nmol/L during pregnancy may be beneficial for testes function in adult sons.

Low serum anti-Müllerian hormone is associated with semen quality in infertile men and not influenced by vitamin D supplementation

BACKGROUND

Anti-Müllerian hormone (AMH) is released by testicular Sertoli cells and of great importance during fetal male sexual development, but less is known about the role of circulating AMH during adulthood. In vitro studies have shown that vitamin D may induce AMH transcription, but a controlled trial investigating the possible effect of vitamin D on serum AMH has not been conducted in men.

METHODS

A single-center, double-blinded, randomized placebo-controlled clinical trial (NCT01304927) conducted in Copenhagen, Denmark. A total of 307 infertile men were included and randomly assigned (1:1) to a single dose of 300,000 IU cholecalciferol followed by 1400 IU cholecalciferol + 500 mg of calcium daily (n = 151) or placebo (n = 156) for 150 days. Difference in serum AMH was a predefined secondary endpoint. Explorative outcomes were associations between serum AMH and gonadal function in infertile men. The primary endpoint was difference in semen quality and has previously been published.

RESULTS

Infertile men in the lowest AMH tertile had significantly lower sperm concentration (∆_T3-1 16 mill/mL (228%); P < 0.001), sperm count (∆_T3-1 55 million (262%); P < 0.001), motile sperm count (∆_T3-1 28 million (255%); P < 0.001), progressive motile sperm count (∆_T3-1 18 million (300%); P < 0.001), testis size (∆_T3-1 2.7 mL (16%); P < 0.001), serum inhibin B (∆_T3-1 72 pg/mL (59%); P < 0.001), inhibin B/FSH ratio (∆_T3-1 48 (145%); P < 0.001), and higher FSH (∆_T3-1 2.6 (38%); P < 0.001) than the tertile of infertile men with highest serum AMH. Vitamin D supplementation had no effect on serum AMH compared with placebo treatment.

CONCLUSIONS

In infertile men, low serum AMH is associated with severely impaired gonadal function illustrated by poor semen quality and lower testosterone/LH ratio. Serum AMH in infertile men was not influenced by vitamin D supplementation.

Associations of serum 25(OH)D levels with physical performance and anabolic hormones in young men

Purpose: The present study examined the association of vitamin D measured by serum 25(OH)D with physical performance outcomes and serum levels of anabolic hormones in young men. Methods: 412 young men (age 19 ± 1 year) entering their compulsory military service volunteered to participate in the study. The study consisted of two groups from two different military bases: Group A was studied in January and group B in July. The groups were first compared with each other and due to statistically significant (p < 0.001 analyzed with independent samples t-test) differences in physical condition (sit-up, push-up, and standing long jump-tests and testosterone levels) between the groups, groups were analyzed separately. The serum levels of 25(OH)D, testosterone (TES), sex hormone binding globulin (SHBG), and insulin-like growth factor-1 (IGF-1) were analyzed by electrochemiluminescence immunoassay. Physical performance tests consisted of muscular fitness (sit-ups, push-ups, standing long jump) and aerobic fitness (12-minute-running) tests. The association of serum 25(OH)D with physical performance tests and anabolic hormones was analyzed using linear regression. Results: After controlling for the group, body mass index, and leisure-time physical activity, serum 25(OH)D level was positively associated with aerobic and muscular fitness (β = 0.15-0.20, all p < 0.05). Also, the participants with sufficient serum 25(OH)D levels (≥75 nmol/L) had better aerobic and muscular fitness and higher TES in group B, and better upper extremity muscular fitness in group A (all p < 0.05). In group A, there were 166 participants with serum levels of 25(OH) D < 75 nmol/L and 18 ≥ 75 nmol/L. In group B, the amounts were 92 (<75 nmol/L) and 136 (≥75 nmol/L), respectively. Conclusion: Serum 25(OH)D was positively associated with both aerobic and muscular fitness and those with sufficient vitamin D levels, had higher levels of TES. Thus, maintaining a sufficient serum 25(OH)D level may be beneficial for physical performance and anabolic state in young men.

Vitamin D supplementation for improving sperm parameters in infertile men: A systematic review and meta-analysis of randomized clinical trials

Objective

Vitamin D has been hypothesized to have a potential role in altering sperm motility and metabolism. However, experimental studies have demonstrated inconsistent results between vitamin D and sperm parameters. This study aims to investigate the role of vitamin D supplementation to improve sperm parameters in infertile men.

Methods

This is a systematic review and meta-analysis study. We comprehensively conducted a search on ClinicalTrials.gov, IRCT.ir, Europe PMC, and PubMed and collected published studies on vitamin D supplementation and sperm parameters for infertile men. The risk of bias was assessed by using Risk of Bias version 2 (RoB v2) and the statistical analysis was performed by using Review Manager 5.4 software.

Results

Five trials with a total of 648 infertile men were included. Our meta-analysis showed that supplementation with vitamin D may significantly improve total sperm motility [mean difference 4.96 (95% CI 0.38, 9.54), p = 0.03, I2 = 69%], progressive sperm motility [mean difference 4.14 (95% CI 0.25, 8.02), p = 0.04, I2 = 89%], and normal sperm morphology [mean difference 0.44 (95% CI 0.30, 0.57), p < 0.00001, I2 = 0%] better than placebo in infertile men. However, total sperm count (p = 0.15), sperm concentration (p = 0.82), and semen volume (p = 0.83) did not differ significantly between two groups.

Conclusions

Vitamin D supplementation may improve sperm motility, progressive sperm motility, and morphology in infertile men. Vitamin D supplementation may be considered in managing male fertility issue.

The Association between Vitamin D and the Components of Male Fertility: A Systematic Review

OBJECTIVE

Previous systematic reviews of the effects of vitamin D on the components of male fertility have been inconclusive. This article systematically reviews the latest research to examine the relationship between vitamin D, semen quality parameters, and sex hormones production.

METHODS

MEDLINE, Cochrane, and Web of Science databases were searched using the appropriate keywords.

RESULTS

Observational studies indicate significant correlation between vitamin D levels and sperm parameters, with a particular emphasis on sperm motility, and partially suggest a relationship between higher serum testosterone and vitamin D levels. Additionally, interventional studies confirmed that vitamin D supplementation has a positive effect on sperm motility, especially progressive. However, most randomized clinical trials indicate that vitamin D treatment does not have any significant effect on testosterone or other hormone levels.

CONCLUSIONS

Although our findings add to the discussion regarding the effect of vitamin D on male fertility, there is still no solid evidence to support the use of vitamin D supplementation to improve the outcomes of patients with impaired sperm parameters and hormonal disorders. Additional dedicated clinical studies are needed to clarify the relationship between vitamin D and male fertility, along with its components.

A bibliometric analysis of global research on vitamin D and reproductive health between 2012 and 2021: Learning from the past, planning for the future

Background

Vitamin D plays an invaluable role in reproductive health, but vitamin D insufficiency and deficiency are generally common among couples of childbearing age and pregnant women. This study aimed to evaluate the evolution, development trend, and research hotspot of publications on vitamin D and reproductive health.

Methods

The literature on vitamin D and reproductive health between 2012 and 2021 was retrieved from the Web of Science Core Collection (WoSCC). We used VOSviewer and CiteSpace to analyze publication years, countries, institutions, journals, highly cited authors and publications, and co-occurrence and citation bursts of keywords.

Results

A total of 1,828 articles and reviews on vitamin D and reproductive health published between 2012 and 2021 were identified. The annual publication outputs showed steady growth, with the most publications (272) and citations (7,097) in 2021. The United States contributed the most publications (458) and had the highest h-index (58). In terms of the number of publications and h-index, the journal named Nutrients ranked first. Nutrition dietetics, obstetrics gynecology, and endocrinology metabolism were three well-represented disciplines in research on vitamin D and reproductive health. Hollis BW, Wagner CL, and Litonjua AA were the top three most productive authors in this field during the last decade. Apart from vitamin D, the five keywords with the most frequent occurrence were vitamin D deficiency, pregnancy, risk, vitamin D supplementation, and 25-hydroxyvitamin D. Keyword citation burst analysis revealed that low birth weight, adipose tissue, marker, and embryo had a citation burst lasting until 2021.

Conclusion

In conclusion, vitamin D has received continuous attention in the field of reproductive health, and there appears to have a higher level of research in North America. Multidisciplinary intersection contributed to the in-depth exploration in this field. And the effect of maternal vitamin D levels on fetal lipid metabolism and the prediction of fertility by vitamin D-related markers might be hotspots for the research.

25-Hydroxyvitamin D Plasma Levels in Natural Populations of Pigmented and Partially Pigmented Land Iguanas from Galápagos (Conolophus spp.)

We report the first data on 25-hydroxyvitamin D plasma levels in natural populations of three species of land iguana endemic to the Galápagos Islands (Conolophus marthae, C. subcristatus, and C. pallidus). The pigment is present throughout the whole body in the skin of C. subcristatus and C. pallidus. On the contrary, pigment is not present in the skin of an extended part of the body in C. marthae. The only existing population of C. marthae is syntopic with a population of C. subcristatus, and the two species are closely related. These circumstances would suggest that, under the assumption that the species show a similar basking behavior and in the absence of compensatory mechanisms, lighter pigmentation should favor higher vitamin D levels. Thus, C. marthae, compared with C. subcristatus in Wolf Volcano, could show higher levels of 25(OH)D plasma levels, or equal, if compensatory mechanisms exist. The three species showed levels in the range of average values for healthy iguanas. However, contrary to the expectation, C. marthae consistently exhibited the lowest 25(OH)D plasma levels. We discuss possible factors affecting vitamin concentration and hypothesize that C. marthae may use the habitat to limit exposure to the high UVB irradiation at Wolf Volcano.

Effect of a single-dose denosumab on semen quality in infertile men (the FITMI study): study protocol for a randomized controlled trial

Background

Infertility is a common problem globally and impaired semen quality is responsible for up to 40% of all cases. Almost all infertile couples are treated with either insemination or assisted reproductive techniques (ARTs) independent of the etiology of infertility because no medical treatment exists. Denosumab is an antibody that blocks RANKL signaling and inhibition of testicular RANKL signaling has been suggested to improve semen quality in a pilot study. This RCT aims to assess whether treatment with denosumab can improve spermatogenesis in infertile men selected by serum AMH as a positive predictive biomarker. This paper describes the design of the study.

Methods/design

FITMI is a sponsor-investigator-initiated, double-blinded, placebo-controlled 1:1, single-center, randomized clinical trial. Subjects will be randomized to receive either a single-dose denosumab 60 mg subcutaneous injection or placebo. The study will be carried out at the Department of Growth and Reproduction, Copenhagen University Hospital, Rigshospitalet, Copenhagen. The primary outcome of the study is defined as the difference in sperm concentration (millions pr. mL) one spermatogenesis (80 days) after inclusion.

Discussion

We describe a protocol for a planned RCT aimed at evaluating whether treatment with denosumab can improve the semen quality in infertile men selected by using serum AMH as a positive predictive biomarker. The results will provide evidence crucial for future treatment in a patient group where there is a huge unmet need.

Trial registration

Clinical Trials.gov NCT05212337. Registered on 14 January 2022.

EudraCT 2021–003,451-42. Registered on 23 June 2021.

Ethical committee H-21040145. Registered on 23 December 2021.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06478-4.

The effect of Vitamin D on testosterone and uncarboxylated osteocalcin levels in aged male rats

There is a well-established complex interaction between vitamin D metabolism and bone and gonad functions. In this study, we aimed to investigate the potential effects of vitamin D therapy on testosterone and osteocalcin (OC) levels in aged male rats. Forty-five adult male rats were divided into three groups in this study. Unlike the control group, the two experimental groups received 50 IU/kg/day and 100 IU/kg/day of vitamin D₃ (cholecalciferol), respectively, for a 4-week period using the gavage method. Testicular tissue and blood samples from rats were collected under general anesthesia at the end of the 4-week period. Testicular tissue samples were examined using light and electron microscopy. Additionally, serum testosterone and OC levels were measured in blood samples. The 50 IU/kg dose of cholecalciferol increased testosterone and OC levels, which were lower than normal due to aging, and regulated the organization of the seminiferous tubule epithelium and interstitium more effectively than the 100 IU/kg dose of cholecalciferol. Male fertility functions and bone health, which degrade due to aging, were increased due to the use of exogenous vitamin D, although the higher dose was not associated with more effective results.

Positive Effect of a New Combination of Antioxidants and Natural Hormone Stimulants for the Treatment of Oligoasthenoteratozoospermia

Oligoasthenoteratozoospermia (OAT) accounts for about 90% of male infertility; in many cases this disorder may be associated with oxidative stress, a condition that decreases the success of fertilization. Therefore, the empirical treatment of male infertility is often based on the use of antioxidants. The aim of the present study was to assess the effectiveness of three months’ administration of a new nutraceutical preparation on hormone profile, sperm parameters and fertilization capability in men undergoing in vitro fertilization (IVF). A total of 36 OAT patients were daily treated for 3 months with a dose of a formulation containing: Inositol, L-Carnitine, Vitamins C, D, E, Coenzyme Q10 and Selenium. Selected parameters were analysed before (T0) and after (T1) treatment, and IVF outcomes were evaluated. We observed an improvement of sperm concentration, motility, morphology and vitality; blood level of testosterone also showed an increase. A significant increase of fertilization rate was detected in 14 couples, whose male partner were treated with the nutraceutical preparation. The present results indicate that a formulation containing antioxidant and energy supply substances was effective in the treatment of sperm alterations and led to significant recovery of fertilizing capacity.

Calcium Homeostasis in the Epididymal Microenvironment: Is Extracellular Calcium a Cofactor for Matrix Gla Protein-Dependent Scavenging Regulated by Vitamins

In the male reproductive tract, the epididymis is an essential organ for sperm maturation, in which sperm cells acquire mobility and the ability to fertilize oocytes while being stored in a protective microenvironment. Epididymal function involves a specialized luminal microenvironment established by the epithelial cells of epididymal mucosa. Low-calcium concentration is a unique feature of this epididymal luminal microenvironment, its relevance and regulation are, however, incompletely understood. In the rat epididymis, the vitamin D-related calcium-dependent TRPV6-TMEM16A channel-coupler has been shown to be involved in fluid transport, and, in a spatially complementary manner, vitamin K2-related γ-glutamyl carboxylase (GGCX)-dependent carboxylation of matrix Gla protein (MGP) plays an essential role in promoting calcium-dependent protein aggregation. An SNP in the human GGCX gene has been associated with asthenozoospermia. In addition, bioinformatic analysis also suggests the involvement of a vitamin B6-axis in calcium-dependent MGP-mediated protein aggregation. These findings suggest that vitamins interact with calcium homeostasis in the epididymis to ensure proper sperm maturation and male fertility. This review article discusses the regulation mechanisms of calcium homeostasis in the epididymis, and the potential role of vitamin interactions on epididymal calcium homeostasis, especially the role of matrix calcium in the epididymal lumen as a cofactor for the carboxylated MGP-mediated scavenging function.

Treatment options for hypercalcemia after cosmetic oil injections: Lessons from human tissue cultures and a pilot intervention study

OBJECTIVE

Granuloma formation following self-administered cosmetic oil injections can lead to severe hypercalcemia and renal calcifications due to extra-renal vitamin D activation. This translational study aims to identify Prednisolone sparing therapeutics for hypercalcemia after development of granulomatous disease secondary to paraffin oil injections.

MATERIALS AND METHODS

Granuloma tissue isolated from five men were cultured ex vivo and treated with selected drugs to block generation of activated vitamin D (1,25(OH)₂D₃). In a retrospective study, we included data before and during different treatments of 21 men with paraffin oil induced granulomatous hypercalcemia (46 treatment courses) where serum calcium, parathyroid hormone, vitamin D metabolites, creatinine and inflammatory markers were measured.

RESULTS

Addition of Ketoconazole or Ciclosporin to granuloma tissue ex vivo culture, significantly suppressed production of 1,25(OH)₂D₃ after 48 h (both p < 0.05). Prednisolone was the first treatment option in most men and lowered serum levels of ionized calcium after 1, 2, 3 and 6 months compared with baseline (p < 0.05). Ketoconazole or Hydroxychloroquine had no significant effect on serum calcium levels and were unable to reduce the concomitant daily Prednisolone doses (p > 0.05). Azathioprine did not reduce calcium levels. However, addition of Tacrolimus to Prednisolone treatment enabled a reduction in Prednisolone dose after 3 months (p = 0.014), but with no additional effect on calcium homeostasis.

CONCLUSION

This study verifies that Prednisolone is an effective treatment and suggests that calcineurin inhibitors may be used as Prednisolone sparing treatment for paraffin oil-induced granulomatous hypercalcemia. Randomized clinical trials are needed to determine clinical efficacy.

25(OH)VitD and human endocrine and functional fertility parameters in women undergoing IVF/ICSI

BACKGROUND

Vitamin D plays an important role in reproduction. Evidence shown that free 25-hydroxyvitamin D (25(OH)VitD) was more accurate than total 25(OH)VitD in reflecting the status of 25(OH)VitD during pregnancy. However, the relationship between free 25(OH)VitD and female fertility parameters has not been reported yet. Therefore, this study aims to compare the correlation of free and total 25(OH)VitD with fertility parameters in infertility females undergoing in vitro fertilization and embryo transfer (IVF-ET) or intracytoplasmic sperm injection (ICSI).

METHODS

According to the inclusion and exclusion criteria, 2569 infertility patients who received IVF-ET or ICSI treatment for the first time participated in this study. Five milliliter peripheral blood samples of the patients were collected on the day before embryo transfer (ET). Enzyme linked immunosorbent assay (ELISA) kits was used to detect free 25(OH)VitD and total 25(OH)VitD, and clinical information was collected. Spearman's rho was used to evaluate the association between the variables.

RESULTS

The median (IQR) of free 25(OH)VitD was 4.71 (4.11-5.31) pg/mL and total 25(OH)VitD was 19.54 (16.52-22.83) ng/m. The correlation between them, however, was week (rho=0.311). Compared to total 25(OH)VitD, free 25(OH)VitD was slightly better correlated with basal follicle-stimulating hormone (FSH) (rho=0.041, P=0.036), basal estradiol (E₂) (rho=0.089, P<0.001), anti-Müllerian hormone (AMH) (rho=-0.057, P=0.004), antral follicle count (AFC) (rho=-0.053, P=0.007), E₂ (rho=-0.080, P<0.001), number of oocytes retrieval (rho=-0.079, P<0.001) and progesterone (P)/E₂ on hCG trigger day (rho=0.081, P<0.001).

CONCLUSIONS

Overall, there was only a rather weak correlation of free as well as total 25(OH)VitD with human endocrine and functional fertility parameters in women undergoing IVF/ICSI. Neither free nor total 25(OH)VitD seems to play a major role in human embryo implantation.

Insights into the perspective correlation between vitamin D and regulation of hormones: sex hormones and prolactin

Aim. Vitamin D is currently an exciting research target, besides its obvious role in calcium homeostasis and bone health, enormous work is being directed at examining the effects of this vitamin on various biological functions and pathological conditions.

Material and methods. The review of the literature and the analysis took about six months and was carried out through PubMed. This is a search engine opening mainly the MEDLINE database of trusted references. We called up all studies written in English that were published between the years 2004 to 2021 and that came through using the applied search terms, and analysed all those that met the criteria.

Results. The endocrine system with its many glands and hormones and their essential roles in the maintenance of normal body functioning cannot be far from interactions with vitamin D. Male and female sex hormones are no exceptions and many studies have investigated the correlations between these hormones and vitamin D. As such, direct and indirect relationships have been found between vitamin D, its receptors or one of its metabolising enzymes with sex hormones and the development of reproductive organs in males and females.

Conclusion. This review summarises the research investigating the associations of vitamin D with sex hormones and reproductive organs in males and females, and thus may pave the road for future studies that will investigate the clinical significance of vitamin D in the management of reproductive system disorders. Despite some conflicting results about the relationship between VD and the effectiveness of the reproductive system, many studies confirm the presence of receptors for this vitamin in the reproductive system, and this supports the direct or indirect relationship between VD and prolactin or VD and testosterone through PO4 and Ca2+ homeostasis, or production of osteocalcin. Therefore, VD is positively associated with semen quality and androgen status. Furthermore, a direct relationship between VD and the production of progesterone, estrogen and estrone in human ovarian cells has been supported by many studies.

Association Between Serum Vitamin D Concentration with Spermiogram Parameters and Reproductive Hormones Among Infertile Iranian Males: a Cross-sectional Study

Infertility is a health concern affecting more than 186 million people globally, and male factors play a role in almost half of cases. Recently, the possible impact of vitamin D on male reproduction has become the center of attention. Our study intended to assess the correlation between serum vitamin D concentrations with sperm parameters and sex hormones in infertile Iranian men compared to fertile men. This cross-sectional study was performed among the 114 couples who were referred to the Urology Clinic of Imam Reza hospital in Mashhad, Iran. According to the inclusion criteria, 57 patients were entered into the infertility group, and 57 cases entered into the fertile group. Semen quality assessment was performed based on WHO guidelines, and the serum was analyzed for 25-hydroxy vitamin D, LH (luteinizing hormone), FSH (follicle-stimulating hormone), and testosterone by ELISA method. Vitamin D level was significantly higher in the fertile group compared with infertile males (p < 0.001). Moreover, vitamin D level was positively correlated with some fertility indicators assessed by spermiogram test including sperm motility (p < 0.001, r = 0.483) and sperm count (p = 0.019, r = 0.216). Additionally, vitamin D was positively associated with testosterone level (p = 0.025, r = 0.210). There was no significant correlation between vitamin D concentrations with sperms morphology, LH, and FSH level. Our study showed a significantly lower vitamin D level in infertile males compared to the fertile group. In conclusion, our study results showed a positive correlation between serum vitamin D with sperm motility, sperm count, and serum testosterone level in fertile males compared to infertile men and suggest the beneficial effects of vitamin D on male reproduction.

Vitamin D3 Supplementation Effects on Spermatogram and Oxidative Stress Biomarkers in Asthenozoospermia Infertile Men: a Randomized, Triple-Blind, Placebo-Controlled Clinical Trial

The objective is to evaluate the effects of vitamin D3 (VD3) on sperm parameters and seminal and serum oxidative stress (OS) biomarkers in asthenozoospermia infertile men. This randomized, triple-masking, placebo-controlled clinical trial conducted on 86 asthenozoospermia infertile men with serum 25 hydroxy vitamin D3 (25-OH-D3) < 30 ng/ml in the infertility clinic of Ahvaz Jahad Daneshgahi, Iran. Patients were randomly allocated to groups A and B, who received daily 4000 IU vitamin D3 (VD3) and matching placebo respectively for 3 months. Demographic data, dietary intake, physical activity, sun exposure, anthropometric indices, serum and seminal levels of MDA (Malondialdehyde), 8-hydroxy-2- Dioxy Guanosine (8-OHDG), total antioxidant capacity (TAC) and calcium, sperm DNA fragmentation index (DFI), serum 25-OH-D3, parathyroid hormone (PTH), phosphorus, and sperm parameters were assessed. VD3 supplementation had no significant effects on body weight, body mass index (BMI), waist circumference (WC), body fat (BF), 8-OHDG, DFI, semen volume, sperm count, and normal sperm morphology, but increased post-intervention mean and mean change of serum 25-OH-D3 (P < 0.001, P < 0.001), PTH (P < 0.001, P < 0.001) and phosphorus (P = 0.009, P = 0.049) and seminal calcium (P = 0.035, P = 0.038) and serum calcium (P = 0.008, P = 0.009), seminal TAC (P < 0.001, P < 0.001), and serum TAC (P = 0.007, P = 005), total sperm motility (P < 0.001, P < 0.001) and progressive sperm motility (P < 0.001, P < 0.001) and decreased seminal MDA (P = 0.017, P = 0.004) and serum MDA (P = 006, P = 0.005) significantly compared to the baseline and placebo group respectively. VD3 supplementation may modulate OS and affect sperm motility in men with asthenozoospermia and serum 25-OH-D3 < 30 ng/ml. Iran Clinical Trials Registry, ID: IRCT20151128025274N4, registered on 28 March 2018, URL of trial registry record: https://www.irct.ir/trial/29983.

Correlative studies on vitamin D and total, free bioavailable testosterone levels in young, healthy men

The relationship between vitamin D levels and testicular hormonal function in men has not been clearly established. Therefore, we aimed to investigate the relationship between deficiency/insufficiency levels of 25(OH)D and luteinizing hormone (LH), follicle-stimulating hormone (FSH), total (TT), free (FT), and bioavailable testosterone (BT), and sex hormone binding globulin (SHBG) in young, healthy men. We enrolled 176 healthy, active young men aged 18–35 years from a genetically homogenous population of Lower Silesia, Poland. Serum levels of 25(OH)D, LH, FSH, and TT were measured by electrochemiluminescence (ECLIA). FT levels were measured by enzyme-linked immunosorbent assay (ELISA). BT levels were calculated from TT, SHBG, and albumin. SHBG was measured by chemiluminescent immunoassay CLIA. We did not find any significant differences between the mean hormonal values (LH, FSH, TT, FT, BT, and SHBG) and the status of 25(OH)D level (deficient and insufficient). Based on our results, we concluded that there is no relationship between deficient and insufficient 25(OH)D concentration and androgen levels in young, healthy men.

The effects of P. atlantica as a libido booster and sexual enhancer on the reproductive system of male rats

Background and aim

Experimental procedure

Results and conclusion

•

Fertility and infertility are among the most complex issues in medical sciences.

•

Baneh (wild pistachio) traditionally is known as a sexual enhancer.

•

It enhances testosterone and oxytocin level in favour of increasing sperm counts.

•

Baneh improves lipid metabolism and increases the serum level of Zinc and vitamin D.

Male vitamin D status and male factor infertility

OBJECTIVE

To determine the association between vitamin D levels in the male partner and fertility outcomes in couples with mild male factor infertility.

DESIGN

Secondary analysis of a randomized, controlled trial.

SETTING

Nine fertility centers in the United States.

PATIENT(S)

Men (n = 154) with sperm concentration between 5 and 15 million/mL, motility ≤40%, or normal morphology ≤4% were eligible. Female partners were ovulatory, ≤40 years old, and had documented tubal patency.

INTERVENTION(S)

Men provided semen and blood at baseline for semen analysis and 25-hydroxyvitamin D (25(OH)D) levels. They were randomly assigned to receive a vitamin formulation including vitamin D 2,000 IU daily or placebo for up to 6 months. Couples attempted to conceive naturally during the first 3 months and with clomiphene citrate with intrauterine insemination of the female partner in months 4 through 6.

MAIN OUTCOME MEASURE(S)

Primary: sperm concentration, motility, morphology, and DNA fragmentation at baseline. Secondary: cumulative pregnancy, miscarriage, and live birth rates.

RESULT(S)

Semen parameters and sperm DNA fragmentation were not statistically significantly different between men with vitamin D deficiency and men with 25(OH)D levels ≥20 ng/mL. In addition, clinical pregnancy and live birth rates were similar. Male 25(OH)D level <20 ng/mL was associated with a higher rate of pregnancy loss (adjusted odds ratio 9.0; 95% confidence interval 1.3 to 61.3).

CONCLUSION(S)

Vitamin D deficiency in the male partner did not significantly impact semen parameters or treatment outcomes. Further study is warranted to better characterize the rate of miscarriage in couples with male vitamin D deficiency.

Male infertility: Role of vitamin D and oxidative stress markers

Spermatozoa are vulnerable to oxidative stress because of their inherent reduced antioxidant defence and DNA repair mechanisms. Polyunsaturated fatty acids in sperm plasma membrane break down to cytotoxic lipid aldehyde, 4-Hydroxynonenal, whereas 3-Nitrotyrosine is generated by peroxynitrite induced tyrosine nitration. Both oxidative stress markers contribute to altered sperm function and infertility. Vitamin D, a membrane antioxidant, has a potential scavenger capacity. We compared oxidative stress markers and vitamin D in male subjects with normal and altered sperm parameters and explored association of these markers: 4-Hydroxynonenal and 3-Nitrotyrosine with Vitamin D. Higher 4-Hydroxynonenal levels in altered sperm parameter group and a negative correlation with sperm count, motility and morphology (p < 0.001) was observed. Vitamin D serum concentration in altered sperm parameters was less (p = 0.016) showing a significant positive correlation with sperm count and morphology. 4-Hydroxynonenal was significantly higher in altered sperm parameters showing negative correlation with vitamin D. Highest serum concentrations of 4-Hydroxynonenal were observed in vitamin D-deficient subjects. Significantly higher concentration of 4-Hydroxynonenal was estimated in altered sperm parameters of vitamin D sufficient group (p < 0.001). This suggests 4-Hydroxynonenal as an oxidative stress marker leading to altered sperm function and infertility with some association with vitamin D; needs to be explored.

The effects of Vitamin D3 supplementation on Spermatogram and endocrine factors in asthenozoospermia infertile men: a randomized, triple blind, placebo-controlled clinical trial

OBJECTIVE

Evaluate the effects of vitamin D3 (VD3) on sperm parameters and endocrine markers in infertile men with asthenozoospermia.

MATERIALS AND METHODS

This randomized, triple-masking, placebo-controlled clinical trial conducted on 86 asthenozoospermia infertile men with serum 25 hydroxy vitamin D3 (25(OH)VD3) < 30 ng/ml in the infertility clinic of Ahvaz Jahad daneshgahi, Iran. Patients were randomly allocated to groups A and B, who received daily 4000 IU VD3 and matching placebo respectively for 3 months. Demographic data, dietary intake, physical activity, sun exposure, anthropometric indices, serum 25(OH)VD3, luteinizing hormone (LH), follicle-stimulating hormone (FSH), total testosterone (T), estradiol (E2),, sex hormone-binding globulin (SHBG), free androgen index (FAI = T/SHBG. 100), T/LH and T/E2 ratios, prolactin (PRO), parathyroid hormone (PTH), osteocalcin (OCN), phosphorus and sperm parameters were assessed.

RESULTS

Three months VD3 supplementation with 4000 IU/day had no significant effects body weight, body mass index (BMI), waist circumference (WC), body fat (BF), serum, OCN, LH, FSH, T, E2, SHBG, PRO, T/E2 ratio, FAI, semen volume, sperm count and normal sperm morphology. It increases serum 25(OH)VD3, PTH and phosphorus and seminal and serum calcium, T/LH ratio and total and progressive sperm motility and decreased significantly compared to the baseline and placebo group.

CONCLUSION

VD3 supplementation may affect sperm motility in men with asthenozoospermia and serum 25(OH)VD3 < 30 ng/ml.

TRIAL REGISTRATION

Iran Clinical Trials Registry, ID: IRCT20151128025274N4, registered on 28 March 2018, URL of trial registry record: https://www.irct.ir/trial/29983.

Revised manuscript R2, clean version are serum levels of 25-hydroxy vitamin D reduced following orchiectomy in testicular cancer patients?

Background

The testis represents one place where the progenitor of vitamin D is converted into its active form. Loss of one testis was suggested to result in reduced vitamin D serum levels. Vitamin D deficiency would represent a significant health problem in the long-term course of patients with testicular germ cell tumors (GCTs) since most of them survive. The purpose of this study was to look to the serum 25(OH)-Vitamin D (25OHD) levels in patients with GCTs before and after orchiectomy. A total of 177 GCT patients underwent measurements of serum 25OHD levels, thereof 83 with preoperative measurements and 94 with measurements at six particular time-points from immediate postoperatively to >24 months. Longitudinal assessments of 25OHD serum levels were performed in individual patients with repeated measurements. A second analysis involved patient cohorts with measurements at six postoperative time-points. Serum levels of patients were also compared with 2 control groups, one consisting of 84 patients with non-neoplastic testicular diseases and another with 237 patients with non-neoplastic urologic diseases. We also looked to associations of 25OHD levels with levels of testosterone, follicle stimulating hormone (FSH), age, histology of GCT and season. Descriptive statistical methods were employed to compare groups and to analyze changes over time.

Results

Normal serum levels of 25OHD were found in 21.7%, 23.1%, 20.2%, 21.9% in GCT patients preoperatively, after >2 years, in control group 1 and control group 2, respectively. Levels were significantly higher in spring and summer, but no association was found with other parameters. We found a significant transient decrease of 25OHD levels with a nadir at 6-12 months after orchiectomy and a recovery thereafter.

Conclusion

Contrasting with previous studies we found no permanent reduction of serum 25OHD levels after orchiectomy but transient postoperative drop of 25OHD levels. There were no associations of 25OHD levels with age, and levels of testosterone or FSH. Our results may point to a particular role of the testis in vitamin D metabolism and may thus enhance the understanding of the diverse physiological roles of the testis.

Evaluation of the effect of vitamin D supplementation on spermatogram, seminal and serum levels of oxidative stress indices in asthenospermia infertile men: a study protocol for a triple-blind, randomized controlled trial

BACKGROUND

It is suggested that vitamin D may have a beneficial role in male reproduction. The male reproductive system is a target tissue for vitamin D. This study will aim to evaluate the effects of vitamin D supplementation on sperm parameters, seminal and serum levels of oxidative stress and serum endocrine factors in asthenospermia infertile men.

METHODS/DESIGN

This randomized, triple-blind, placebo-controlled clinical trial will be conducted on 86 infertile men with idiopathic asthenozoospermia (the mobility of sperm < 40% and rapid progressive sperm motility < 32%), with serum levels of vitamin D less than 30 ng / ml in the "Infertility Clinic of Ahvaz Jahad daneshgahi", Iran.

MAIN OUTCOMES MEASURE (S)

Demographic data, dietary intake, physical activity, sun exposure, anthropometric indices, serum and seminal levels of MDA (Malondialdehyde), 8-hydroxy-2- Dioxy Guanosine (8-OHDG), Total Antioxidant Capacity (TAC) and calcium, sperm DNA fragmentation index (DFI), serum 25-OHD, luteinizing hormone (LH), follicle-stimulating hormone (FSH), total testosterone (T), estradiol (E2), sex hormone-binding globulin (SHBG), free androgen index (FAI = T/SHBG. 100), T/LH and T/E2 ratios, prolactin (PRO), parathyroid hormone (PTH), osteocalcin (OCN), phosphorus and sperm parameters.

DISCUSSION

The deficiency of vitamin D as an antioxidant is common all over the world. Numerous observational studies have shown a positive association between vitamin D levels and semen quality. However, few clinical studies have been conducted in this area. So considering with the high prevalence of this antioxidant deficiency specifically in infertile men, it seems that the supplementation of vitamin D in infertile men with insufficient levels or deficiency may improve the status of oxidative stress and thereby may affect sperm parameters and endocrine factors involved in male fertility.

TRIAL REGISTRATION

Iran Clinical Trials Registry, ID: IRCT20151128025274N4 , registered on 28 March 2018.

Testosterone, cortisol, vitamin D and oxydative stress and their relationships in professional soccer players

BACKGROUND

The testosterone/cortisol ratio has been used in sport physiology to evaluate the balance between anabolism and catabolism; its decrease below 30% has been considered a marker of overtraining. In this framework recent studies in soccer players have investigated the relationships between testosterone, cortisol, vitamin D and reactive oxygen species, but with unconvincing results. The aim of the present study was to evaluate the behavior of such biological parameters and their relationships both in winter (the season of championship) and in summer (off-competition season), characterized by different homeostatic situations.

PATIENTS AND METHODS

Twenty-seven professional male football players (Second Italian Division), were studied. Blood levels of free testosterone, cortisol, vitamin D and reactive oxygen species were evaluated in August (pre-season training) and in February, in the midseason. A comparison between these two periods was performed and for each of them the relationships between the biological parameters were evaluated.

RESULTS

Blood levels of testosterone were higher during summer whereas those of cortisol were higher in winter. Vitamin D levels were higher in summer; in this season a positive significant relationship between vitamin D and testosterone was observed (p=0.001), but not in winter (p=0.592). Reactive oxygen species were higher in winter; in this season a significant positive relationship between these substances and cortisol was observed (0.000), but not in summer (p=0.325).

CONCLUSIONS

In professional soccer players it was found a positive relationship between vitamin D and testosterone in summer and between reactive oxygen species and cortisol in winter. However the question whether such results are genuine cause-effect relationships or mere casual or spurious statistical correlations is still unsolved. As matter of fact, such results could be dependent from other determinants which might drive the aforementioned biological parameters in the same direction. These conclusions must be considered valid only in relation to the experimental conditions (training workload, diet and sun exposure) of the present study.

Proteomics analysis reveals the effect of 1α,25(OH)2VD3-glycosides on development of early testes in piglets

1α,25(OH)₂VD₃ is the most active form of VD3 in animals. It plays an important role in regulating mineral metabolism but also in reproduction. Testes are the main reproductive organs of male mammals. Our research aims to reveal the effect of 1α,25(OH)₂VD₃-glycosides on development of early testes in piglets. 140 weaned 21-day old piglets were selected. The piglets were randomly divided into four groups and were fed a commercial diet supplemented with 0, 1, 2 and 4 μg/kg of 1α,25(OH)₂VD₃, provided as 1α,25(OH)₂VD₃-glycosides. Sixty days after the start of the experiment, at piglet age 82 days, testes were harvested. The morphology and histology of early testicular development were assessed. In addition, the proteomic TMT/iTRAQ labelling technique was used to analyse the protein profile of the testes in each group. Western blotting was applied to verify the target of differentially abundant proteins (DAPs). The analysis of morphology and histology of testes showed that a certain concentration of 1α,25(OH)₂VD₃-glycosides had a positive and significant effect on testicular development. And the results of proteomics analysis showed that of the identified 132,715 peptides, 122,755 were unique peptides. 7852 proteins, of which 6573 proteins contain quantitative information. Screening for DAPs focused on proteins closely related to the regulation of testicular development such as steroid hormone synthesis, steroid biosynthesis, peroxisome and fatty acid metabolism pathways. These results indicated that 1α,25(OH)₂VD₃ is involved in the regulation of early testicular development in piglets. At the same time, these findings provide valuable information for the proteins involved in the regulation of testicular development, and help to better understand the mechanisms of 1α,25(OH)₂VD₃ in regulating the development of piglets’ testes.

Estradiol and 1α,25(OH)2 vitamin D3 share plasma membrane downstream signal transduction through calcium influx and genomic activation in immature rat testis

The aim of this study was to investigate the rapid response pathway and gene and protein expression profiles of the rat testis in response to estradiol (E₂) and 1α,25(OH)₂ vitamin D₃ (1,25-D₃), to understand how they mediate their effects on the first spermatogenic wave. To do this, we compared the effects of 1,25-D₃ and E₂ on ⁴⁵calcium(Ca²⁺) uptake and the involvement of estrogen receptors (ESR) in their rapid responses. Additionally, we studied the downstream signal transduction effects of 1,25-D₃ and E₂ on cyclin A1/B1 and cellular cycle protein expression. As previously observed for 1,25-D₃, E₂ also increased ⁴⁵Ca²⁺ uptake in immature rat testes via voltage-dependent Ca²⁺ channels, Ca²⁺-dependent chloride channels and via the activation of protein kinase C, protein kinase A and mitogen-activated protein kinase kinase (MEK). Elevated aromatase expression by testes was observed in the presence of 1,25-D₃ and both hormones decreased ESR mRNA expression. Furthermore, 1,25-D₃ and E₂ diminished cyclin A1 mRNA expression, but E₂ did not affect cyclin B1 mRNA levels. Consistent with these findings, the immunocontent of cyclin A1 and B1 in the testes was also increased by 1,25-D₃ and E₂. 1,25-D₃ increased expressions of the p16 and p53 proteins, supporting the anti-proliferative and pro-apoptotic properties of 1,25-D_3, while E₂ also augmented p16. Data indicate that both hormones trigger rapid responses at the plasma membrane that may control the expression of gene and proteins related to cell cycle regulation, and thereby modulate spermatogenesis.

Vitamin D Deficiency in Testicular Cancer Survivors: A Systematic Review

Testicular cancer (TC) is the most frequent tumor in young males. In the vast majority of cases, it is a curable disease; therefore, very often patients experience a long survival, also due to their young age at diagnosis. In the last decades, the role of the vitamin D deficiency related to orchiectomy has become an increasingly debated topic. Indeed, vitamin D is essential in bone metabolism and many other metabolic pathways, so its deficiency could lead to various metabolic disorders especially in long-term TC survivors. In our article, we report data from studies that evaluated the incidence of hypovitaminosis D in TC survivors compared with cohorts of healthy peers and we discuss molecular mechanisms and clinical implications.

Triterpene betulin may be involved in the acute effects of pulp and paper mill effluent on testis physiology in zebrafish

Pulp and paper mill effluent can cause changes in the morphology and energy metabolism in the zebrafish (Danio rerio) testis. Betulin, a naturally occurring triterpene is commonly present in this type of effluent and is suspected of being involved in these effects. The aim of this study was to compare the effects pulp and paper mill effluent and betulin on various aspects of testicular physiology in the zebrafish. This included the in vitro effects of effluent and betulin on testicular lactate content and lactate dehydrogenase (LDH) activity. In addition, the effects of betulin on glucose uptake, glycogen, alanine aminotransferase (ALT), reactive oxygen and nitrogen species formation and oxidative damage in the testes were determined. Furthermore, we compared the effects and mechanism of action of betulin and effluent on calcium homeostasis in testes. In vitro exposure to both effluent and betulin decreased lactate and calcium influx, possibly due to the activation of the sodium‑calcium exchanger (NCX) pump. Additionally, betulin-treated testes had higher reactive oxygen species (ROS) and reduced glutathione (GSH) content, as well as increased glutathione transferase (GST) activity and a tendency towards decreased catalase (CAT) activity. Thus, this study shows that alterations in testis physiology caused by the pulp and paper mill effluent in the testis may be due in part to the actions of betulin.

Estrogens and development of the rete testis, efferent ductules, epididymis and vas deferens

Estrogen has always been considered the female hormone and testosterone the male hormone. However, estrogen's presence in the testis and deleterious effects of estrogen treatment during development have been known for nearly 90 years, long before estrogen receptors (ESRs) were discovered. Eventually it was learned that testes actually synthesize high levels of estradiol (E2) and sequester high concentrations in the reproductive tract lumen, which seems contradictory to the overwhelming number of studies showing reproductive pathology following exogenous estrogen exposures. For too long, the developmental pathology of estrogen has dominated our thinking, even resulting in the "estrogen hypothesis" as related to the testicular dysgenesis syndrome. However, these early studies and the development of an Esr1 knockout mouse led to a deluge of research into estrogen's potential role in and disruption of development and function of the male reproductive system. What is new is that estrogen action in the male cannot be divorced from that of androgen. This paper presents what is known about components of the estrogen pathway, including its synthesis and target receptors, and the need to achieve a balance between androgen- and estrogen-action in male reproductive tract differentiation and adult functions. The review focuses on what is known regarding development of the male reproductive tract, from the rete testis to the vas deferens, and examines the expression of estrogen receptors and presence of aromatase in the male reproductive system, traces the evidence provided by estrogen-associated knockout and transgenic animal models and discusses the effects of fetal and postnatal exposures to estrogens. Hopefully, there will be enough here to stimulate discussions and new investigations of the androgen:estrogen balance that seems to be essential for development of the male reproductive tract.

Positive effect of a new supplementation of vitamin D3 with myo-inositol, folic acid and melatonin on IVF outcomes: a prospective randomized and controlled pilot study

To assess whether oral supplementation of vitamin D₃, myo-inositol, folic acid and melatonin affects IVF outcomes. One hundred and twenty consecutive infertile women attending IVF treatment were 1:1 randomly distributed in two groups. Women in group A (control) were assigned to receive myo-inositol, alpha-lactalbumin and folic acid in the morning, and myo-inositol, folic acid and melatonin in the evening. Women in group B (treated) were assigned to receive analogous treatment, with the addition of cholecalciferol (vitamin D₃) in the evening from the early beginning of the luteal phase. 50 patients in group A and 50 in group B underwent blastocyst transfer and were considered in the statistical analysis. Vitamin D₃ levels significantly increased after 45 days of treatment: 33.2 ng/ml in group B Vs. 24.3 ng/ml in group A (p < .0001). The implantation rate increased as well: 37.1% in group B Vs. 19.2% in group A (p < .0151). Overall, the results indicate that increased vitamin D₃ levels positively correlate with the implantation rate in IVF. Because of the low number of participants, these findings need to be confirmed with larger cohorts of patients.