Male fertility is improved in many ways by vitamin D

Vitamin D and male reproduction

Nature Reviews Endocrinology 10, 175–186 (2014) doi:10.1038/nrendo.2013.262

Martin Blomberg Jensen, University Department of Growth and Reproduction, Rigshospitalet, Section 5064, Blegdamsvej 9, 2100 Copenhagen, Denmark.

Vitamin D is a versatile signalling molecule with a well-established role in the regulation of calcium homeostasis and bone health. The spectrum of vitamin D target organs has expanded and the reproductive role of vitamin D is highlighted by expression of the vitamin D receptor (VDR) and enzymes that metabolize vitamin D in

  • testis,

  • male reproductive tract and

  • human spermatozoa.

The expression levels of VDR and CYP24A1 in human spermatozoa serve as positive predictive markers of semen quality , and VDR mediates a nongenomic increase in intracellular calcium concentration that induces sperm motility. Interestingly, functional animal models show that vitamin D is important for estrogen signalling and sperm motility, while cross-sectional studies support the positive association between serum 25-hydroxyvitamin D level and sperm motility in both fertile and infertile men. Expression of VDR and enzymes that metabolize vitamin D in fetal testis indicates a yet unknown role during development, which may be extrapolated from invasive testicular germ cell tumours where 1Ξ±,25-dihydroxyvitamin D induces a mesodermal differentiation of the pluripotent testicular cancer cells.

Taken together, vitamin D signalling has a positive effect on

  • semen quality,

  • increases estrogen responsiveness and

  • differentiates germ cell tumours.

Future studies are needed to determine when 1Ξ±,25-dihydroxyvitamin D acts in a paracrine manner and whether systemic changes, which are subject to pharmacological modulation, could influence male reproductive function.

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Martin Blomberg Jensen

Competing interests statement

The author declares that he holds two patent applications related to vitamin D and reproduction (patent WO/1016/17116 and WO/2012/116699).

Martin Blomberg Jensen studied medicine at the University of Copenhagen and obtained an MD degree in 2006. His interest in calcium and vitamin D signalling started during two clinical assignments at the department of Nephrology and Endocrinology, Rigshospitalet, Denmark. Since 2008, he has worked as an independent scientist under the supervision of Prof. Anders Juul in Department of Growth and Reproduction at Rigshospitalet, Denmark. His research has focused on the characterization of vitamin D signalling in male reproduction, which in part addresses the important relationship between bone signalling and gonadal function. The relationship between calcium homeostasis and male reproduction has not been characterized completely, and he is currently studying the role of selected vitamin D regulated genes and testicular regulators of vitamin D metabolism for male reproductive function.