scholarly journals Vitamin D metabolism, sex hormones, and male reproductive function

Reproduction ◽  
2012 ◽  
Vol 144 (2) ◽  
pp. 135-152 ◽  
Author(s):  
Martin Blomberg Jensen

The spectrum of vitamin D (VD)-mediated effects has expanded in recent years, and VD is now recognized as a versatile signaling molecule rather than being solely a regulator of bone health and calcium homeostasis. One of the recently identified target areas of VD is male reproductive function. The VD receptor (VDR) and the VD metabolizing enzyme expression studies documented the presence of this system in the testes, mature spermatozoa, and ejaculatory tract, suggesting that both systemic and local VD metabolism may influence male reproductive function. However, it is still debated which cell is the main VD target in the testis and to what extent VD is important for sex hormone production and function of spermatozoa. This review summarizes descriptive studies on testicular VD metabolism and spatial distribution of VDR and the VD metabolizing enzymes in the mammalian testes and discusses mechanistic and association studies conducted in animals and humans. The reviewed evidence suggests some effects of VD on estrogen and testosterone biosynthesis and implicates involvement of both systemic and local VD metabolism in the regulation of male fertility potential.

1973 ◽  
Vol 53 (2) ◽  
pp. 327-372 ◽  
Author(s):  
J L Omdahl ◽  
H F DeLuca

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Sarah A. Howles ◽  
Akira Wiberg ◽  
Michelle Goldsworthy ◽  
Asha L. Bayliss ◽  
Anna K. Gluck ◽  
...  

AbstractKidney stone disease (nephrolithiasis) is a major clinical and economic health burden with a heritability of ~45–60%. We present genome-wide association studies in British and Japanese populations and a trans-ethnic meta-analysis that include 12,123 cases and 417,378 controls, and identify 20 nephrolithiasis-associated loci, seven of which are previously unreported. A CYP24A1 locus is predicted to affect vitamin D metabolism and five loci, DGKD, DGKH, WDR72, GPIC1, and BCR, are predicted to influence calcium-sensing receptor (CaSR) signaling. In a validation cohort of only nephrolithiasis patients, the CYP24A1-associated locus correlates with serum calcium concentration and a number of nephrolithiasis episodes while the DGKD-associated locus correlates with urinary calcium excretion. In vitro, DGKD knockdown impairs CaSR-signal transduction, an effect rectified with the calcimimetic cinacalcet. Our findings indicate that studies of genotype-guided precision-medicine approaches, including withholding vitamin D supplementation and targeting vitamin D activation or CaSR-signaling pathways in patients with recurrent kidney stones, are warranted.


2013 ◽  
Vol 59 (5) ◽  
pp. 771-780 ◽  
Author(s):  
Shoaib Afzal ◽  
Stig E Bojesen ◽  
Børge G Nordestgaard

BACKGROUND Tobacco smoke chemicals may influence vitamin D metabolism and function, and conversely vitamin D may modify the carcinogenicity of tobacco smoke chemicals. We tested the hypothesis that lower plasma 25-hydroxyvitamin D [25(OH)D] is associated with a higher risk of tobacco-related cancer in the general population. METHODS A prospective population-based cohort of 9791 individuals from the Copenhagen City Heart Study who were free of cancer at baseline was followed from 1981–1983 until December 2008 with 100% complete follow-up. RESULTS During up to 28 years of follow-up, 1081 participants developed a tobacco-related cancer and 1506 developed other cancers. Decreasing 25(OH)D concentrations, subdivided by clinical categories or by seasonally adjusted percentile categories, were associated with increasing cumulative incidence of tobacco-related cancer (log-rank trend P = 2 × 10−6 and P = 5 × 10−9). Multivariable adjusted hazard ratios of tobacco-related cancer were 1.75 (95% CI, 1.33–2.30) for 25(OH)D <5 vs ≥20 ng/mL, and 2.07 (1.63–2.62) for ≤5th vs >66th percentile. Also, multivariable adjusted hazard ratios for a 50% reduction in 25(OH)D were 1.20 (1.13–1.28) for any tobacco-related cancer, 1.19 (95% CI, 1.09–1.31) for lung cancer, 1.44 (1.19–1.73) for head and neck cancer, 1.28 (1.06–1.54) for bladder cancer, 1.34 (1.04–1.73) for kidney cancer, and 0.95 (0.89–1.01) for other cancers. CONCLUSIONS Lower plasma 25(OH)D was associated with higher risk of tobacco-related cancers, but not with risk of other cancers.


2016 ◽  
Vol 86 (5-6) ◽  
pp. 198-241 ◽  
Author(s):  
Alberto Rosenblatt ◽  
Joel Faintuch ◽  
Ivan Cecconello

Abstract. Androgens and estrogens play a key role regarding sexual life and reproduction. Along with hypotestosteronemia, obese men exhibit a 2-fold increase in estradiol concentration, adversely infl uencing these parameters. Estrogens and adipokines also infl uence bone metabolism, exerting a direct effect on vitamin D, calcium homeostasis and bone health. Bariatric procedures normalize some sex hormones, and may reverse several obesity-related conditions. Estrogens levels may remain elevated postoperatively, and despite its protective effect on the skeleton, bariatric patients are more prone to fractures when compared to the general population. Multiple nutritional defi cits are common after bariatric interventions, and hypozincemia is the most likely to negatively infl uence reproductive parameters. Zinc is an essential element for normal spermatogenesis, and severe hypozincemia is associated with infertility in both sexes. Vitamin D also acts as a regulator of several enzymes involved in steroid hormone production, and its defi ciency could impair reproductive function. Few studies have addressed changes in sex hormones and in reproductive function in the male bariatric population, as they represent a minority of surgical candidates. Although obesity rates and burden are similar for both sexes, society is more lenient with the obese male. Moreover, 73 % of overweight/obese men are satisfi ed with their health, causing body weight and obesity-related health problems to increase when they opt for bariatric surgery. In the present article, we discuss shifts of sex hormones before and after bariatric surgery, surgery impact on semen quality, skeletal health and nutrients, and new research directions regarding links between vitamin D, zinc, androgens and reproduction.


1978 ◽  
Vol 138 (Suppl_5) ◽  
pp. 836 ◽  
Author(s):  
Hector F. DeLuca

2014 ◽  
Vol 21 (11) ◽  
pp. 1414-1422 ◽  
Author(s):  
Julie H Laursen ◽  
Helle Bach Søndergaard ◽  
Anders Albrechtsen ◽  
Ruth Frikke-Schmidt ◽  
Nils Koch-Henriksen ◽  
...  

Background: Evidence is accumulating supporting a beneficial effect of vitamin D in multiple sclerosis (MS). Genome-wide association studies (GWAS) have shown significant associations between 25-hydroxyvitamin D (25(OH)D) and single nucleotide polymorphisms (SNPs) in key genes in the vitamin D metabolism. Objective: To examine the association between 25(OH)D and six GWAS SNPs and environmental factors in 1497 MS patients. Methods: Blood samples and lifestyle questionnaires were collected between 2009 and 2012. Genotyping of GC-, CYP2R1- and NADSYN1-SNPs was performed by TaqMan allelic discrimination (Life Technologies). Results: We found significant associations between 25(OH)D and SNPs in GC (rs7041, p = 0.01 and rs2282679, p = 0.03) and CYP2R1 (rs10741657, p =1.8 × 10−4). Season of blood sampling (p = 2.8 × 10−31), sex ( p = 1.9 × 10−5), BMI ( p = 2.3 × 10−5), vitamin supplements ( p = 7.0 × 10−22), and fish intake ( p = 0.02) also had significant effects on 25(OH)D. Conclusion: In this cross-sectional study, we found significant effects of environmental factors and SNPs in GC and CYP2R1 on 25(OH)D in MS patients. Since 25(OH)D might have protective effects in MS, and vitamin D supply is a modifiable factor, it may be important to include this in the MS treatment regimen.


2021 ◽  
Vol 1 (2) ◽  
pp. 46-62
Author(s):  
E. A. Dontseva ◽  
V. V. Trefilova ◽  
T. E. Popova ◽  
M. M. Petrova ◽  
M. Al-Zamil

Anticonvulsant-induced osteoporosis (AIO) and associated pain syndromes and patient disabilities are an important interdisciplinary medical problem generated by various molecular, genetic and pathophysiological mechanisms. AIO are the most important pathological processes associated with chronic pain in adults with epilepsy. Standard approaches to their prevention and treatment do not always solve the problem of the progression of the pathological process and chronicity of AIO. This is the reason for the search for new personalized strategies for the prevention and treatment of AIO. Vitamin D metabolism, expression and specificity of vitamin D receptors (VDRs) may play a key role in the development of AIO and chronic back pain in patients with epilepsy. The aim of the study was to review publications on changes in the vitamin D system in patients with AIO. We searched for articles published in e-Library, PubMed, Oxford Press, Clinical Case, Springer, Elsevier, and Google Scholar. The search was carried out by key-words and their combinations. The role of vitamin D and VDR in the development of AIO and the chronicity of back pain has been demonstrated mainly in animal models and humans. Associative genetic studies have shown that single nucleotide variants (SNVs) of the VDR gene encoding VDR may be associated with the development of osteoporosis of the spine (including those associated with the intake of an anticonvulsants). The prospects for the use of vitamin D preparations for modulating the effect of anticonvulsants used to treat epilepsy are discussed. Genetic association studies of VDR gene SNVs are important for understanding the genetic predictors of AIO and chronic back pain in patients with epilepsy, as well as for developing new personalized pharmacotherapy strategies.


Nature ◽  
1980 ◽  
Vol 283 (5742) ◽  
pp. 115-115
Author(s):  
R. H. Wasserman

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