Vitamin D and Male Fertility: An Updated Review

Abstract

To date, the key role of vitamin D in male reproductive system has been suggested, since the expression of vitamin D receptors and metabolizing enzymes was demonstrated in the testis and spermatozoa. Nevertheless, a general consensus about the role of vitamin D in male fertility is still debated. The aim of this review is to provide an updated systematic revision of the current available literature, discussing the experimental and clinical evidence on the role of vitamin D in the regulation of testis hormone production, seminal parameters and male fertility. The consequences of vitamin D deficiency on serum levels of testicular hormones have been analysed by several observational and interventional studies, with controversial results. Equally, the experimental researches not were able to state a certain relationship between vitamin D status and testis hormone production. Possible bias, including age, body mass index, and baseline vitamin D status justified the differences among studies. As well as concerning the effect of vitamin D on semen parameters, most of the studies agreed in the possibility that vitamin D might have a positive effect on human male fertility potential, particularly through better sperm motility. Regarding pregnancy outcomes, normal level of vitamin D seems to be related to better pregnancies. However, all the previous studies displayed a wide heterogeneity in study design, population, methodology, and cut off values used for the evaluation of vitamin D status. Future studies are needed to better clarify the exact role of vitamin D on hormonal and seminal panel in both fertile and infertile men.

Stereological assessment of the effects of vitamin D deficiency on the rat testis

“…Spermatogenesis is a multistep process regulated by complex interplay of endocrine, paracrine, and autocrine factors in addition to proper function of Sertoli and Leydig cells. Active VD metabolites modulate a wide range of genes throughout the body [ 24 ], but whether they are necessary for male reproductive function is far from clear [ 6 , 25 , 26 ]. In this comparative stereological evaluation of testis in the vitamin D-deficient Sprague Dawley rats, a considerable decline in germ cell populations accompanied by severe impairment of spermatogenesis and reduced androgen production was found.…”

“…In the context of the non-classical effects of VD in the biology of mammalian species, its impact on reproductive organs has received more attention in recent decades. Indeed, the established presence of vitamin D receptor (VDR) and VD metabolizing enzymes in male genital tract [ 3 , 4 ] prompted several investigators to search for the relation between low vitamin D status as a common problem [ 5 ] and various kinds of male reproductive function including androgen production and spermatogenesis [ 6 , 7 ].…”

“…Meanwhile, a general agreement about the exact role of VD in male fertility is still a subject of debate [ 6 , 8 ]. Moreover, hypocalcemia and changes in other regulatory factors of calcium homeostasis such as parathyroid hormone often accompany VD deficiency and are a real barrier for proper interpretation of VD mediated effects [ 9 , 10 ].…”

Vitamin D Deficiency in Testicular Cancer Survivors: A Systematic Review

“…However, even if the correlation between vitamin D and hypogonadism is not entirely clear, it must be considered that the expression of hydroxylases (CYP2R1 and CYP27B1) and VDR in testis tissue [ 47 , 62 , 63 , 64 ] also represents a further indication of the importance of the testicles in the metabolism of vitamin D [ 65 , 66 , 67 ]. It seems apparent in contrast with the finding of some vitamin D recovery starting from the second year of follow-up, but in reality, this could be explained in two ways: (1) progressive compensation by the contralateral testis (if unilateral), or (2) compensation by other organs that normally express hydroxylases CYP2R1 and CYP27B1, such as liver and kidney (especially in the case of bilateral tumor).…”

Антиоксиданты Как Способ Повышения Мужской Фертильности

“…В последние годы витамин D представляет интерес как предмет исследования из-за его плейотропной роли, включая аутокринную, паракринную и эндокринную функцию в нескольких целевых органах и системах (кишечнике, скелетной системе, почках и околощитовидных железах) [18]. Основная активность этой молекулы, относящейся к группе секостероидов, заключается в регуляции гомеостаза кальция и фосфора, способствующего минерализации костей [18][19][20]. Установлено, что дефицит витамина D негативно влияет на качество спермы и функцию гормонов как у животных, так и у людей.…”