Vitamin D is important for gonadal function in rodents, and improvement of vitamin D status in men with low sperm counts increases live birth rate. Vitamin D is a regulator of transcellular calcium transport in the intestine and kidney and may influence the dramatic changes in the luminal calcium concentration in epididymis. Here, we show spatial expression in the male reproductive tract of vitamin D receptor (VDR)-regulated factors involved in calcium transport: Transient receptor potential vanilloid 5/6 (TRPV5/6), sodium/calcium exchanger 1 (NCX1), plasma membrane calcium ATPase 1 (PMCA1), calbindin D9k, calcium-sensing receptor (CaSR), and parathyroid hormone-related peptide (PTHrP) in mouse and human testis and epididymis. Testicular Casr expression was lower in Vdr ablated mice compared with controls. Moreover, expression levels of Casr and Pthrp were strongly correlated in both testis and epididymis and Pthrp was suppressed by 1,25(OH)2D3 in a spermatogonial cell line. The expression of CaSR in epididymis may be of greater importance than in the gonad in mice as germ cell-specific Casr deficient mice had no major reproductive phenotype, and coincubation with a CaSR-agonist had no effect on human sperm-oocyte binding. In humans, seminal calcium concentration between 5-10 mM was associated with a higher fraction of motile and morphologically normal sperm cells and the seminal calcium concentration was not associated with serum calcium levels. In conclusion, VDR regulates CaSR and PTHrP, and both factors may be involved in the regulation of calcium transport in the male reproductive tract with possible implications for sperm function and storage.
Context Vitamin D has been linked with glucose and lipid metabolism. Men with impaired gonadal function have a higher risk of metabolic syndrome and mortality, and vitamin D status may be a reversible modulator. Objective Determine the effect of daily vitamin D and calcium supplementation for 150 days on glucose and lipid homeostasis in infertile men. Design A single-center, double-blinded, randomized clinical trial (NCT01304927), 307 infertile men were randomized (1:1) to a single dose of 300,000 IU cholecalciferol followed by 1,400 IU cholecalciferol + 500 mg of calcium daily (n=151) or placebo (n=156) for 150 days. Reported metabolic parameters including fasting plasma glucose, HbA1c, fasting serum insulin, homeostatic model assessment of insulin resistance (HOMA-IR), fasting plasma cholesterols and triglyceride were secondary endpoints. The primary endpoint semen quality has previously been reported. Results Men receiving vitamin D supplementation improved their vitamin D status, while vitamin D status was aggravated in the placebo group characterized by higher serum parathyroid hormone (PTH). At end of trial, men receiving vitamin D supplementation had 13% lower fasting serum insulin concentrations compared with the placebo-treated group (65 vs. 74 pmol/L, P = 0.018) and 19% lower HOMA-IR (2.2 vs. 2.7, P = 0.025). Moreover, men in the vitamin D group had higher high-density lipoprotein (HDL) cholesterol levels (1.38 vs. 1.32 mmol/L, P = 0.008) compared with the placebo group. Conclusion High-dose vitamin D supplementation had beneficial effects on glucose homeostasis and HDL cholesterol levels in infertile men.
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.
ObjectiveVitamin 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?DesignA 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.MethodsA 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.ResultsAfter 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.ConclusionVitamin 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.
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.
A normal functioning hypothalamic-pituitary-testicular axis is required for normal testicular descent. The percentage of cases that result from a disturbance in this axis remains controversial. Much has yet to be learnt about cryptorchidism, but is seems that the existence of A dark spermatogonia (Ad spermatogonia) is essential for later fertility. Bilateral cryptorchid patients have a high risk of later infertility, even though they undergo early surgery for cryptorchidism. It is possible today to distinguish-to a certain extent-between three different groups of cryptorchid patients based on testicular histology, gonadotropins, and inhibin B at the time of early surgery: Group 1, patients suspected of prepubertal transient hypothalamic-pituitary-testicular hypofunction and a high risk of later infertility; Group 2, patients with hypergonadotropic hypogonadism and a primary testicular dysfunction; and Group 3, patients with normal histology and normal serum levels of inhibin B and gonadotropins at the time of early surgery and a low risk of later infertility. Given the potential adverse effects of hormonal treatment, attention should be directed toward small doses of adjuvant gonadotropin-releasing hormone (GnRH) treatment for those who might benefit the most, that is, bilateral cryptorchid boys at early surgery without evidence of normal maturation of gonocytes into Ad spermatogonia. Optimally, gonadotropin levels in such patients should be measured to ensure that levels are not compensatory elevated, thereby supporting the suspicion of hypothalamic-pituitary-testicular hypofunction. Studies of GnRH-supplementary treatment should include testicular biopsy at surgery and at follow-up in childhood as well as examinations of fertility potential in adulthood.
Neonatal pyogenic liver abscess is rare and potentially lethal. We present a six-week-old infant with pseudoparalysis of the right arm.
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