Vitamin D and fertility: a systematic review

Effect of micronutrient supplementation on IVF outcomes: a systematic review of the literature

There is accumulating evidence on the importance of micronutrients in improving fertility in couples undergoing IVF therapy. Despite this, studies reporting the relevant clinical outcomes of IVF, such as pregnancy and live birth rates, are very scarce. This review aimed to systematically summarize clinical evidence on the effect of micronutrients on primary outcome parameters of IVF treatment. The literature was searched up to February 2017 through Embase and PubMed databases for relevant studies. The quality of eligible studies was assessed with the Downs and Black checklist. A total of five studies qualified for inclusion. These studies reported outcomes on 467 participants administered micronutrient supplements alone or combined with other nutrients as part of IVF therapy. There was significant heterogeneity among the interventions and study designs. However, all the studies reported a positive impact of micronutrient supplementation on clinical outcomes of IVF therapy in terms of pregnancy rate and/or live birth rate. Within the limits of this review, micronutrients appear to influence positive outcomes in couples undergoing fertility treatment. Larger clinical studies are needed to strengthen these findings so that the benefit of micronutrients can be extended to subjects undergoing IVF therapy.

Association of vitamin D intake and serum levels with fertility: results from the Lifestyle and Fertility Study

OBJECTIVE

To evaluate the role of vitamin D intake and serum levels on conception of clinical pregnancy and live birth.

DESIGN

Prospective cohort study.

SETTING

Academic medical centers.

PATIENT(S)

Healthy, nulliparous women, age 18-39 years, and their male partners.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Clinical pregnancy and live birth were compared between those who did or did not meet the vitamin D estimated average requirement (EAR) intake (10 μg/d) and with serum 25-hydroxyvitamin D (25(OH)D) considered at risk for inadequacy or deficiency (<50 nmol/L) or sufficient (≥50 nmol/L).

RESULT(S)

Among 132 women, 37.1% did not meet the vitamin D EAR and 13.9% had serum levels at risk for inadequacy or deficiency. Clinical pregnancies were significantly higher among women who met the vitamin D EAR (67.5% vs. 49.0%) and with sufficient serum 25(OH)D (64.3% vs. 38.9%) compared with those who did not. Live births were higher among those who met the vitamin D EAR (59.0% vs. 40.0%). The adjusted odds ratio (AOR) of conceiving a clinical pregnancy was significantly higher among those who met the EAR (AOR = 2.26; 95% confidence interval [CI], 1.05-4.86) and had sufficient serum 25(OH)D (AOR = 3.37; 95% CI, 1.06-10.70). The associations were not significant after controlling for selected nutrients and dietary quality.

CONCLUSION(S)

Women with vitamin D intake below EAR and serum 25(OH)D levels at risk for inadequacy or deficiency may be less likely to conceive and might benefit from increased vitamin D intake to achieve adequacy.

CLINICAL TRIAL REGISTRATION NUMBER

NCT00642590.

Interactions between oestrogen and 1α,25(OH)2-vitamin D3 signalling and their roles in spermatogenesis and spermatozoa functions

Oestrogens and 1α,25(OH)₂-vitamin D₃ (1,25-D₃) are steroids that can provide effects by binding to their receptors localised in the cytoplasm and in the nucleus or the plasma membrane respectively inducing genomic and non-genomic effects. As confirmed notably by invalidation of the genes, coding for their receptors as tested with mice with in vivo and in vitro treatments, oestrogens and 1,25-D₃ are regulators of spermatogenesis. Moreover, some functions of ejaculated spermatozoa as viability, DNA integrity, motility, capacitation, acrosome reaction and fertilizing ability are targets for these hormones. The studies conducted on their mechanisms of action, even though not completely elicited, have allowed the demonstration of putative interactions between their signalling pathways that are worth examining more closely. The present review focuses on the elements regulated by oestrogens and 1,25-D₃ in the testis and spermatozoa as well as the interactions between the signalling pathways of both hormones.

The role of vitamin D supplementation on erectile function

In the last few years growing evidence highlighted vitamin D (VD) deficiency is one of the several dynamics that associates with increased atherosclerotic cardiovascular (ASCV) diseases. ASCV diseases and erectile dysfunction (ED) share common risk factors such as diabetes mellitus, hypertension, smoking, hyperlipidemia, and a sedentary lifestyle. The aim of this review was to summarize current progress in VD research by focusing effect of low VD level on different body systems and erectile function. Here we examine research linking VD deficiency and ED and discuss how VD influences ED and its classic risk factors that also associate to increased ED risk. We also summarize research indicating that VD associates with reduced risk of several nonvascular contributing factors for ED. Available literature demonstrates relatively high rates of low VD serum levels in ED patients. Based on the preclinical and clinical data available in the literature, to date, we infer that VD play a critical role in maintaining erectile function in humans. Nevertheless, this should also be tested through randomized controlled studies on the effect of VD supplementation with larger population.

Association of serum vitamin D with osteosarcopenic obesity: Korea National Health and Nutrition Examination Survey 2008-2010

BACKGROUND

Serum vitamin D levels have been reported to be associated with individual components of body composition. However, the relationship between serum vitamin D and combined indices of adverse body composition is largely unknown. This cross-sectional study examined the association between serum vitamin D and osteosarcopenic obesity in a nationally representative sample of middle-aged and older adults.

METHODS

We analysed the Korea National Health and Nutrition Examination Surveys (IV and V) conducted in 2008-2010, consisting of 5908 (2485 men, 3423 women) aged ≥ 50 years. Serum vitamin D levels were determined by radioimmunoassay, and body composition was evaluated by dual-energy x-ray absorptiometry. The association between serum vitamin D levels and the number of abnormalities in body composition, including osteosarcopenic obesity, a low bone and muscle mass with concurrent high fat mass, was analysed by multinomial logistic regression adjusting for covariates.

RESULTS

In men, after controlling for covariates, higher vitamin D levels were associated with a significantly reduced likelihood of the number of phenotypes of adverse body composition (P for trend < 0.05). Those in the highest tertile group of serum vitamin D levels, compared with those in the lowest tertile, were less likely to have adverse body composition, numbering one (odds ratio [OR] = 0.67, 95% confidence interval [CI]: 0.49, 0.92), two (OR = 0.49, 95% CI: 0.33, 0.73), and three (osteosarcopenic obesity; OR = 0.42, 95% CI: 0.26, 0.67). In women, those in the highest tertile group of serum vitamin D levels, compared with those in the lowest tertile, were less likely to have osteosarcopenic obesity (OR = 0.55, 95% CI: 0.33, 0.93). Vitamin D deficiency (<20 ng/mL) in men was significantly associated with an increased likelihood of a higher number of adverse body composition, especially for osteosarcopenic obesity (OR = 2.08, 95% CI: 1.42, 3.03). Vitamin D deficient women, compared with those having normal levels of serum vitamin D, were also more likely to demonstrate osteosarcopenic obesity (OR = 1.99, 95% CI: 1.30, 3.05).

CONCLUSIONS

A high serum vitamin D level in mid- and late-life was associated with reduced odds of multiple adverse body composition, especially osteosarcopenic obesity, suggesting potential health benefits of maintaining adequate levels of vitamin D.

Vitamin D treatment improves levels of sexual hormones, metabolic parameters and erectile function in middle-aged vitamin D deficient men

BACKGROUND

The associations between serum vitamin D (VD), serum testosterone (TT) and metabolic syndrome are complex and with limited published research, particularly on the effects of VD treatment on sexual hormones, erectile function and the metabolic syndrome.

OBJECTIVES

This study assessed whether a monthly high dose VD treatment for 12 months in VD deficient middle-aged men was associated with: changes in levels of sexual hormones, improvement of diabetes control and metabolic syndrome components, better erectile function [International Index of Erectile Function (IIEF)-5 questionnaire]; and changes in a prostate marker.

MATERIALS AND METHODS

Descriptive research of a prospective study, conducted between October 2014 and September 2015, 102 male patients ≥35 [(±SD: 53.2 ± 10.5), (range 35-64)] years with deficient serum VD level (<30 ng/mL) were included in the study. Participants were followed up for one year, with monitoring at 3-, 6-, 9- and 12-months. At the initial baseline visit, a complete medical examination was conducted, and blood was drawn for laboratory tests for above biochemical and hormonal variables under examination. Participants received an initial VD (Ergocalciferol; oral solution 600 000 IU/1.5 ml), and followed a VD treatment regime thereafter. At the four follow up visits (3, 6, 9 and 12 months), blood was collected, and patients' erectile function was evaluated by IIEF-5 questionnaire.

MAIN OUTCOME MEASURES

During the follow up visits, all the biochemical and hormonal (TT, estradiol and luteinizing hormones, HbA1c, serum lipids profile) were assessed, and patients' erectile function was evaluated by IIEF-5 questionnaire.

RESULTS

Patients' mean age was 53.2 ± 10.4 years. Serum VD exhibited significant increments (p <0.001) from baseline (15.16 ± 4.64 ng/mL), to 3 (31.90 ± 15.99 ng/mL), 6 (37.23 ± 12.42 ng/mL), 9 (44.88 ± 14.49 ng/mL) and 12 months (48.54 ± 11.62 ng/mL), and there was significant stepladder increases in both serum TT level (12.46 ± 3.30 to 15.99 ± 1.84 nmol/L) and erectile function scores (13.88 ± 3.96 to 20.25 ± 3.24) (p <0.001 for both). We also observed significant stepladder decreases in estradiol (87.90 ± 27.16 to 69.85 ± 14.80 pmol/L, p = 0.001), PTH (from 58.52 ± 28.99 to 38.33 ± 19.44 pg/mL, p <0.001) and HbA1c levels (7.41 ± 2.85 to 6.66 ± 1.67%, p = 0.001). Mean BMI significantly decreased from 33.91 ± 6.67 to 33.14 ± 6.35 kg/m² (p = 0.001); and PSA values significantly increased from 0.59 ± 0.30 to 0.82 ± 0.39 ng/mL (p <0.001) at the end of the 12 months' follow-up. There were no changes in LH levels.

CONCLUSION

This study demonstrated that VD treatment improves testosterone levels, metabolic syndrome and erectile function in middle-aged men. More randomized placebo-controlled interventional trials of VD treatment in patients with the metabolic syndrome and low TT could assist in uncovering the putative roles of VD.

Evaluation of Relationship between Body Mass Index with Vitamin D Receptor Gene Expression and Vitamin D Levels of Follicular Fluid in Overweight Patients with Polycystic Ovary Syndrome

BACKGROUND

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder associated with reproductive disorders and metabolic dysfunctions including insulin resistance. The roles of vitamin D in the regulation of metabolic modulations specifically involving insulin and reproduction processing are introduced. In addition, obesity appears to be closely associated with severity of PCOS. The present study is to evaluate the effect of body mass index (BMI) on vitamin D levels in follicular fluid and vitamin D receptor (VDR) expression levels in granulos cells.

MATERIALS AND METHODS

A comparative study was conducted on 80 women with average age of 20-35 years referred for in vitro fertilization (IVF). Patients were divided into four groups, and serum levels of testosterone and insulin resistance (IR) were evaluated at the puncture time. Also, vitamin D levels of follicular fluid were evaluated. VDR gene expression was assayed by quantified-polymerase chain reaction (PCR) technique. Correlations were evaluated with calculation of the Spearman coefficient, and also independent relationships were assessed by means of multiple regression analysis.

RESULTS

Vitamin D levels of follicular fluid decreased in PCOS patients compared with non-PCOS. Also, over-weight individuals had lower vitamin D levels compared with normal-weight patients. Vitamin D levels of follicular fluid were highly correlated with BMI (r=-0.51, P<0.01). Homeostatic model assessment-IR (HOMA-IR) values were significantly higher in women of PCOS/overweight and PCOS/normal weight in comparison with women of non-PCOS/normal weight (P<0.01). The gene expression data of VDR in granulosa cells were significantly lower in the PCOS/overweight group compared with the non-PCOS/normal weight (P<0.01).

CONCLUSION

The findings indicated significant differences in VDR gene expression in granulosa cells and vitamin D of follicular fluid in PCOS/overweight patients.

Molecular actions of vitamin D in reproductive cell biology

Vitamin D (VitD) is an important secosteroid and has attracted attention in several areas of research due to common VitD deficiency in the population, and its potential to regulate molecular pathways related to chronic and inflammatory diseases. VitD metabolites and the VitD receptor (VDR) influence many tissues including those of the reproductive system. VDR expression has been demonstrated in various cell types of the male reproductive tract, including spermatozoa and germ cells, and in female reproductive tissues including the ovaries, placenta and endometrium. However, the molecular role of VitD signalling and metabolism in reproductive function have not been fully established. Consequently, the aim of this work is to review current metabolic and molecular aspects of the VitD–VDR axis in reproductive medicine and to propose the direction of future research. Specifically, the influence of VitD on sperm motility, calcium handling, capacitation, acrosin reaction and lipid metabolism is examined. In addition, we will also discuss the effect of VitD on sex hormone secretion and receptor expression in primary granulosa cells, along with the impact on cytokine production in trophoblast cells. The review concludes with a discussion of the recent developments in VitD–VDR signalling specifically related to altered cellular bioenergetics, which is an emerging concept in the field of reproductive medicine.

Vitamin D Deficiency Does Not Influence Reproductive Outcomes of IVF-ICSI: A Study of Oocyte Donors and Recipients

Background:

Vitamin D and its active metabolite, 1,25-dihydroxy vitamin D (1,25-(OH)₂D₃), play a significant role in reproduction.

Aim:

To assess the effect of serum 25-hydroxy vitamin D level on oocyte quality and endometrial receptivity by studying oocyte donors and their recipients.

Materials and Methods:

This prospective study consisted of two groups: Group A (recipient group) and Group B (donor group). All the participants of Groups A1 and B1 as well as Groups A2 and B2 were subcategorized into vitamin D-deficient (<20 ng/mL) and vitamin D replete-insufficient (20 to ≥30 ng/mL), respectively.

Results:

In the recipient group, out of the 192 participants, 123 were in A1 group, and 69 were in A2 group. In donor group, out of the 99 participants, 54 were in B1 group, and 45 in B2 group. In the recipient group, Group A2 had a higher clinical pregnancy rate, implantation rate and ongoing pregnancy rate, and a lower abortion rate as compared to that of A1, but these are statistically insignificant. The difference in endometrial thickness and number of embryos transferred between both groups was insignificant. In the donor group, the total number of days of controlled ovarian hyperstimulation, the dose of gonadotropins, the number of oocytes retrieved, the percentage of mature oocytes, and the percentage of usable embryos were higher in Group B2 than those in Group B1, but these are statistically insignificant. The fertilization rate was statistically insignificant between Groups B1 and B2.

Conclusion:

Vitamin D deficiency leads to lower reproductive outcomes, though not statistically significant and, thereby, does not have a negative influence on in-vitro fertilization–intracytoplasmic sperm injection outcomes.

Pathogenetic role of vitamin D deficiency in the development of menstrual dysfunction in pubertal girls: a literature review

In the literature review, 50 scientific sources surrounding the problem of vitamin D deficiency, 80% of which amounted to the issuance of the last 5 years, have been analyzed. Despite the impact of vitamin D deficiency on the health of children and adolescents has been studied for a long time, the information on the role of vitamin D in the formation of menstrual function in pubertal girls is scant and ambiguous. Among the hypotheses of menstrual dysfunction with vitamin D deficiency, neurohumoral regulation of the hypothalamic-pituitary-ovarian system is considered to be essential due to the localization of vitamin D receptors (VDR), unlike other vitamins, in the nuclei of various tissues and organs. However, in the last 10 years, data on the role of genetic polymorphism of the VDR gene in the pathogenesis of various manifestations of menstrual dysfunction have been accumulated. Some studies indicated a beneficial effect of cholecalciferol on such menstrual dysfunctions as oligomenorrhea and dysmenorrhea. Regarding numerous data on the role of vitamin D, both traditional and recently published, there is a strong correlation between vitamin D deficiency and other various factors, determining a wide range of polymorphic clinical manifestations where menstrual dysfunction is essential in girls at the age of puberty.

Women with Recurrent Miscarriage Have Decreased Expression of 25-Hydroxyvitamin D3-1α-Hydroxylase by the Fetal-Maternal Interface

Background

Effects of vitamin D deficiency in pregnancy have been associated with some adverse pregnancy outcomes. The 25-hydroxyvitamin D₃-1α-hydroxylase (CYP27B1) is integral to the vitamin D metabolic pathway. The enzyme catalyzes localized conversion of pro-hormone 25-hydroxyvitamin D₃ to active 1,25-dihydroxyvitamin D₃. Our aim was to investigate the expression of CYP27B1 at the fetal-maternal interface in the first trimester pregnancy and to determine whether CYP27B1 was associated with recurrent miscarriage (RM).

Methods

Expressions of CYP27B1 mRNA and protein in villi and decidua from 20 women undergoing primary miscarriage, 20 women with RM and 20 women with normal pregnancy were evaluated by western blot, and quantitative real-time PCR. The co-localization of CYP27B1 and certain cytokines including IL-10, IFN-γ, TNF-α, and IL-2 expression were examined using immunohistochemistry and confocal microscopy.

Results

Women with RM had a significantly lower expression of CYP27B1 mRNA and protein in villous and decidual tissues compared with the normal pregnant women (P = 0.000 in villus, P = 0.002 in decidua for mRNA; P = 0.036 in villus, P = 0.007 in decidua for protein.). Compared with the normal pregnancy, immunostaining for CYP27B1 was significantly decreased in villous trophoblasts and decidual glandular epithelial cells in RM women. No significant differences in the localization of CYP27B1, IL-10, IFN-γ, TNF-α, and IL-2 expression were identified between the normal pregnant and RM women.

Conclusions

Women with RM have a lower level of CYP27B1 expression in chorionic villi and decidua compared with normal pregnant women, suggesting that reduced CYP27B1 expression may be associated with RM. The consistent localization of CYP27B1 and IL-10, IFN-γ, TNF-α, and IL-2 expression in villous and decidual tissues suggests the importance of the local production of 1,25(OH)₂D₃ at the fetal-maternal interface to regulate cytokine responses.

Association of VDBP and CYP2R1 gene polymorphisms with vitamin D status in women with polycystic ovarian syndrome: a north Indian study

PURPOSE

Polycystic ovarian syndrome (PCOS) is the most common endocrine abnormality among women of reproductive age and is usually associated with oligo-ovulation/anovulation, obesity, and insulin resistance. Hypovitaminosis D may also be a primary factor in the initiation and development of PCOS. However, little is known about the role of genetic variation in vitamin D metabolism in PCOS aetiology. Therefore, we studied the genetic polymorphisms of CYP2R1 and vitamin D binding protein (VDBP) in an Indian population.

METHODS

Serum vitamin D was measured by ELISA. Genotyping of VDBP single nucleotide polymorphisms (SNPs) rs7041 (HaeIII; G>T) and rs4588 (StyI; A>C) and CYP2R1 SNP rs2060793 (HinfI; A>G) was carried out by restriction fragment length polymorphism in 50 cases of PCOS that were compared with 50 age-matched healthy women.

RESULTS

Vitamin D levels were found to be significantly lower in women with PCOS (p = 0.008) than in age-matched controls. There was no significant difference in genotype frequencies of all three polymorphisms (rs7041, rs4588, and rs2060793) between PCOS and control women. In women with a vitamin D deficiency (<20 ng/ml), the GT allele of the VDBP SNP rs7041 (p value =0.04), the VDBP allelic combination Gc1F/1F (T allele of rs4588 and C allele of rs7041) (p value =0.03), and the GA allele of the CYP2R1 SNP rs2060793 (p = 0.05) were associated with an increased risk of developing PCOS.

CONCLUSIONS

The present study shows that the GT allele of VDBP SNP rs7041, the VDBP allelic combination (GC1F/1F), and GA allele of CYP2R1 SNP rs2060793 in vitamin D deficient women increase the risk of PCOS.

Sex-specific vitamin D effects on blood coagulation among overweight adults

BACKGROUND

Overweight adults are at increased risk for cardiovascular disease and vitamin D deficiency, whereas an important feature to vitamin D physiology is its sex dependence. The aim of this study was to examine whether vitamin D status improvement exerts a sexually dimorphic effect on serum proteins associated with cardiovascular risk among overweight adults.

MATERIALS AND METHODS

Unprocessed serum from age- and BMI-matched men (n = 26) and premenopausal women (n = 24) with vitamin D deficiency and after they achieved sufficiency through a 12-month nutritional intervention was analysed using our previously published depletion-free quantitative proteomics method. Key findings were verified with ELISA. Differentially expressed proteins were subjected to in silico bioinformatics assessment using principal component analysis, hierarchical clustering and Metacore^™ pathway analysis. All mass spectrometry proteomic data are available via ProteomeXchange (identifier: PXD003663).

RESULTS

A total of 282 proteins were differentially expressed after the intervention between men and women (P-value ≤ 0·05), in which the blood coagulation pathway was significantly enriched. In agreement with the proteomics findings, ELISA measurements showed vitamin K-dependent protein C, von Willebrand factor, fibrinogen gamma chain and multimerin-1 proteins, of relevance to blood coagulation, to be differentially affected (P-value ≤ 0·05) between sexes after vitamin D status correction.

CONCLUSIONS

This study identified novel protein-level molecular indicators on the sexually dimorphic effect of vitamin D status correction associated with blood coagulation among overweight adults. These sex-mediated vitamin D effects should be factored in the design and interpretation of vitamin D observational and interventional studies testing cardiometabolic outcomes.

Associations of vitamin D status and vitamin D-related polymorphisms with sex hormones in older men

OBJECTIVE

Evidence regarding relationships of serum 25-hydroxyvitamin D (25(OH)D) with sex hormones and gonadotropin concentrations remains inconsistent. Polymorphisms in vitamin D-related genes may underly these relationships. Our aim was to examine the relationship of vitamin D status and polymorphisms in vitamin D-related genes with sex hormone and gonadotropin levels.

DESIGN AND MEASUREMENTS

We analysed data from the Longitudinal Aging Study Amsterdam, an ongoing population-based cohort study of older Dutch individuals (65-89 years). We included data of men with measurements of serum 25-hydroxyvitamin D (25(OH)D) (n=643) and determination of vitamin D-related gene polymorphisms (n=459). 25(OH)D concentrations were classified into four categories: <25, 25-50, 50-75 and >75nmol/L. Outcome measures were total testosterone, calculated bioavailable and free fraction testosterone, SHBG, estradiol, LH and FSH concentrations. Hypogonadism was defined as a total testosterone level <8.0nmol/L.

RESULTS

Serum 25(OH)D was positively associated with total and bioavailable testosterone levels. After adjustments for confounders, men with serum 25(OH)D less than 25 (n=56), 25-50 (n=199) and 50-75nmol/L (n=240) had lower total testosterone levels compared to men with serum 25(OH)D higher than 75nmol/L (n=148) (β (95% confidence interval): -2.1 (-3.7 to -0.4nmol/L), -0.8 (-1.9 to 0.4nmol/L) and -1.4 (-2.4 to -0.3nmol/L), respectively). For bioavailable testosterone the association was significant only for men with serum 25(OH)D less than 25nmol/L (-0.8 (-1.4 to -0.1nmol/L)) compared to men with serum 25(OH)D >75nmol/L. Serum 25(OH)D was not related to SHBG, estradiol or gonadotropin levels. Hypogonadism (n=29) was not associated with lower serum 25(OH)D. No significant differences were found in hormone levels between the different genotypes of the vitamin D-related gene polymorphisms. Also, the polymorphisms did not modify the relationships of serum 25(OH)D with sex hormones or gonadotropins.

CONCLUSION

Vitamin D status is positively associated with testosterone levels. No association was found between vitamin D-related gene polymorphisms and hormone levels.

Preferred natural food of breeding Kakapo is a high value source of calcium and vitamin D

The Kakapo, a large NZ native parrot, is under severe threat of extinction. Kakapo breed only in years when the local podocarps, including rimu (Dacrydium cupressinum), are fruiting heavily, and the fruit are the preferred food both in the diet of breeding females and for provisioning chicks. Attempts to provide a supplementary food during years of poor fruit supply have failed to encourage breeding. Nutrient analysis of rimu berries reveals high calcium content (8.4mg/g dry matter) which would be essential for both egg shell production and the growing skeleton of the chick. Vitamin D is also critical for these processes and for the maintenance of calcium homeostasis, but the source of vitamin D for these nocturnal, ground-dwelling vegetarians is unknown.

OBJECTIVE

To examine the vitamin D status of adult Kakapo, and to investigate the possibility that rimu berries provide vitamin D as well as calcium, thus differentiating them from the supplementary foods provided to date.

METHOD

Previously collected and frozen serum from 10 adult birds (6 females, 4 males) was assayed for 25(OH)D₃ and D₂. Two batches of previously frozen rimu berries were analysed for vitamin D₃ and D₂.

RESULTS

Vitamin D status of the 10 adult birds was very low; mean 4.9nmol/l, range 1-14nmol/l 25(OH)D₃. No 25(OH)D₂ was detected in any of the birds. High levels of D₂ and moderate levels of D₃ were found in the rimu berries.

CONCLUSION

Traditionally it has been considered that the D₃ isoform of this endogenously produced secosteroid is produced only in animals. However, D₃ has been reported in the leaves of plants of the Solanacae family (tomato, potato, capsicum). The avian vitamin D receptor (VDR) is thought to have a much greater affinity for the D₃ form. Therefore if rimu fruit are able to provide breeding Kakapo with D₃, and are a plentiful source of calcium, they could be the perfect food package for breeding and nesting birds. Of wider importance, this finding challenges conventional understanding that D3 production is exclusive to animals, and that there are no high concentration food sources of vitamin D.

The Characteristics of Women Who Use Complementary Medicine While Attempting to Conceive: Results from a Nationally Representative Sample of 13,224 Australian Women

BACKGROUND

Preconception is acknowledged globally as an important part of ensuring health for the next generation and is underpinned by principles of health promotion and preventive medicine. There is a demand for more holistic, preventive health care within preconception health services. Many women are also using complementary medicine during their reproductive years.

MATERIALS AND METHODS

This paper presents a longitudinal analysis of women's consultations with a complementary medicine practitioner while attempting to become pregnant, and the characteristics of women who choose to consult a complementary medicine practitioner during the preconception period. The cross-sectional and longitudinal analyses conducted in this study utilise data from the 1973 through 1978 cohort of the Australian Longitudinal Study on Women's Health (n = 13,224). Multivariate logistic regression models and generalized estimating equation models, with and without time lag, were used.

RESULTS

Women who identified as attempting to conceive were more likely to consult with an acupuncturist (adjusted odds ratio, 1.46) or a naturopath/herbalist (adjusted odds ratio, 1.30). Women who consulted with an acupuncturist were likely to be consulting with a specialist doctor (odds ratio, 3.73) and/or have previous fertility issues (odds ratio, 2.30). Women who consulted with a naturopath were more likely to report experiencing premenstrual tension (odds ratio, 2.30) but less likely to have had a previous miscarriage (odds ratio, 0.18).

CONCLUSIONS

Policymakers and other health professionals need to be aware that health professionals who are largely unregulated and structurally isolated from conventional health care may be actively contributing to women's reproductive and physical health during the preconception period.

Beneficial Effects of UV-Radiation: Vitamin D and beyond

Aside from its well-known effects on bone and mineral metabolism, vitamin D may also play an important role in extra-skeletal processes like immunologic diseases, cancer, or cardiovascular diseases. Even though meta-analyses showed that vitamin D supplementation reduces fractures, falls, and overall mortality, its potential benefits did not find universal acclaim. Several health care authorities published Recommended Dietary Allowances (RDAs) for vitamin D, most of them ranging from 600 to 800 international units (IU) per day, corresponding to a serum level of 25-hydroxyvitamin D of at least 20 ng/mL (50 nmol/L). However, studies conducted in the general population revealed a much lower overall intake of vitamin D than the proposed RDAs. Thus, strategies to increase the vitamin D intake in the general population, e.g., food fortification or vitamin D supplementation, are needed to match the existing evidence and recommendations. Therefore, several currently ongoing projects aim to investigate the effect of vitamin D supplementation in the general population and try to establish food-based solutions to improve vitamin D status.

Antioxidants reduce oxidative stress in follicular fluid of aged women undergoing IVF

BACKGROUND

The status characterized by the imbalance between pro-oxidants and antioxidants molecules, defined as oxidative stress, has been suggested to be involved in the pathogenesis of subfertility in females. This study aims to evaluate the impact of a complete micronutrients supplementation on oxidative stress levels in follicular microenvironment as well as on in vitro fertilization (IVF) outcome.

METHODS

This preliminary study was conducted between January 2014 and July 2015 at the Siena University Hospital Infertility Clinic. Serum and follicular fluid were collected from infertile women aged > 39 years who underwent two in vitro fertilization cycles: in the first cycle they were treated with GnRH-antagonist protocol and gonadotropins for controlled ovarian hyperstimulation, whereas in the second cycle ovarian stimulation protocol was associated to micronutrients supplementation, starting three months earlier. Protein oxidation levels and total antioxidant capacity in serum and in follicular fluid were evaluated in IVF cycles with or without micronutrients supplementation. Differences in IVF outcome parameters were statistically evaluated.

RESULTS

Two-dimensional electrophoresis analyses demonstrated that when patients assumed micronutrients before IVF cycles, follicular fluid and serum proteins were protected from oxidative damage. Comparable results were obtained when total antioxidant capacity was measured. Moreover, the mean number of good quality oocytes retrieved when patients received micronutrients supplementation was significantly increased.

CONCLUSION

The additional treatment with micronutrients, starting three months before IVF cycles, protects the follicular microenvironment from oxidative stress, thus increasing the number of good quality oocytes recovered at the pick up.

Nutrients as novel therapeutic approaches for metabolic disturbances in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders among women. This disease is characterized by infertility, menstrual dysfunction, and hyperandrogenism. Also, PCOS is often associated with hyperlipidemia and impaired glucose tolerance, conditions that are associated with cardiovascular disorder, type 2 diabetes, cancer and hypertension. Evidence supports that some nutrients may affect the hormonal and metabolic disturbances of PCOS. Here in this study, we aimed to review the available literature that assessed the nutrients such as inostol, isoflavonids, resveratrol, vitamin D, and PUFA (polyunsaturated fatty acids), known to influence the hormonal and metabolic disturbances of PCOS, along with the strategies and future directions of nutrient supplementations in such patients.

Vitamin D3 deficiency is associated with female sexual dysfunction in premenopausal women

PURPOSE

To assess female sexual functions in women who were affected by vitamin D₃ deficiency.

METHODS

A total of 50 women with FSD and 58 healthy women controls were included in the study, according to the Female Sexual Function Index (FSFI) questionnaire using a 26.55 cutoff value. Detailed medical histories were obtained from all sexual active women, and all women were evaluated in terms of possible presence of depression with the Beck Depression Inventory (BDI). Serum 25-hydroxyvitamin D₃, follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin, total and free testosterone, estradiol, dehydroepiandrosterone-SO₄ (DHEA-SO₄), sex hormone-binding globulin (SHBG), free thyroxine (fT4), and thyroid-stimulating hormone (TSH) levels were measured.

RESULTS

Mean age of premenopausal women was 34.9 ± 6.3 years. The level of serum 25-hydroxyvitamin D₃ was significantly lower in women with FSD compared with the controls (15.9 ± 8.4 and 26.3 ± 11.7 nmol/L, respectively). Desire (p = 0.0001), arousal (p = 0.0001), lubrication (p = 0.002), orgasm (p = 0.0001), satisfaction (p = 0.018), and pain (p = 0.010) domain scores were also correlated with the levels of serum 25-hydroxyvitamin D₃. The BDI score showed a significant negative correlation with the total FSFI score (r = -0.492, p = 0.0001). The FSFI score not showed a significant correlation with the hormones (p > 0.05).

CONCLUSION

There is a relationship with FSD and deficiency of vitamin D₃. Also, increased depressive symptoms were associated with FSD.

Vitamin D and chronic diseases: the current state of the art

The objective was to provide the current state of the art regarding the role of vitamin D in chronic diseases (osteoporosis, cancer, cardiovascular diseases, dementia, autism, type 1 and type 2 diabetes mellitus, male and female fertility). The document was drawn up by panelists that provided their contribution according to their own scientific expertise. Each scientific expert supplied a first draft manuscript on a specific aspect of the document's topic that was subjected to voting by all experts as "yes" (agreement with the content and/or wording) or "no" (disagreement). The adopted rule was that statements supported by ≥75 % of votes would be immediately accepted, while those with <25 % would be rejected outright. Others would be subjected to further discussion and subsequent voting, where ≥67 % support or, in an eventual third round, a majority of ≥50 % would be needed. This document finds that the current evidence support a role for vitamin D in bone health but not in other health conditions. However, subjects with vitamin D deficiency have been found to be at high risk of developing chronic diseases. Therefore, although at the present time there is not sufficient evidence to recommend vitamin D supplementation as treatment of chronic diseases, the treatment of vitamin D deficiency should be desiderable in order to reduce the risk of developing chronic diseases.

Investigation of 7-dehydrocholesterol reductase pathway to elucidate off-target prenatal effects of pharmaceuticals: a systematic review

Mendelian diseases contain important biological information regarding developmental effects of gene mutations that can guide drug discovery and toxicity efforts. In this review, we focus on Smith–Lemli–Opitz syndrome (SLOS), a rare Mendelian disease characterized by compound heterozygous mutations in 7-dehydrocholesterol reductase (DHCR7) resulting in severe fetal deformities. We present a compilation of SLOS-inducing DHCR7 mutations and the geographic distribution of those mutations in healthy and diseased populations. We observed that several mutations thought to be disease causing occur in healthy populations, indicating an incomplete understanding of the condition and highlighting new research opportunities. We describe the functional environment around DHCR7, including pharmacological DHCR7 inhibitors and cholesterol and vitamin D synthesis. Using PubMed, we investigated the fetal outcomes following prenatal exposure to DHCR7 modulators. First-trimester exposure to DHCR7 inhibitors resulted in outcomes similar to those of known teratogens (50 vs 48% born-healthy). DHCR7 activity should be considered during drug development and prenatal toxicity assessment.

The effect of vitamin D on primary dysmenorrhea with vitamin D deficiency: a randomized double-blind controlled clinical trial

Dysmenorrhea is common among women of reproductive age. This study aim was to investigate the effect of vitamin D (vit D) supplementation in treatment of primary dysmenorrhea with vit D deficiency. A randomized double-blind placebo-controlled clinical trial was conducted on 60 women with primary dysmenorrhea and vit D deficiency referred to our clinic at Arash Women's Hospital from September 2013 to December 2014. Eligible women were randomly assigned into treatment and control groups (30 in each group). Individuals in the treatment group received 50 000 IU oral vit D and the control group received placebo weekly for eight weeks. After two months of treatment, there was a significant difference in serum vit D concentration between the two groups (p < 0.001). Pain severity decreased significantly in treatment group after eight weeks of treatment. There was a significant difference in pain intensity between the two groups after eight weeks of treatment and one month after the end of treatment (p < 0.001 for both). A weekly high dose (50 000 IU) oral vit D supplementation for eight weeks in patients with primary dysmenorrhea and vit D deficiency could improve pain intensity.

Assessment of vitamin D receptors in alopecia areata and androgenetic alopecia

BACKGROUND

Alopecia areata (AA) is a frequent autoimmune disease, the pathogenesis of which is still unknown. Androgenetic alopecia (AGA) is a noncicatricial type of patterned hair loss. Expression of vitamin D receptors (VDRs) on keratinocytes is essential for maintenance of normal hair cycle, especially anagen initiation.

OBJECTIVE

To assess VDRs in the skin and blood of AA and AGA patients, in order to evaluate their possible role in these hair diseases.

METHODS

This study recruited 20 patients with AA, 20 patients with AGA, and 20 healthy controls. Blood samples and lesional scalp biopsies were taken from all participants for detection of VDR levels.

RESULTS

Serum and tissue VDR levels were lower in AA as well as AGA patients when compared to controls (P = 0.000). Serum and tissue VDR were positively correlated in each group. Tissue VDR was significantly lower in female patients with AA than males (P = 0.046) although serum and tissue VDR levels were significantly higher in female AGA patients than males (P = 0.004).

CONCLUSION

This study suggests an important role for VDR in the pathogenesis of AA and AGA through documenting lower serum and tissue VDR levels in AA and AGA patients in comparison with controls.

Protein pathways working in human follicular fluid: the future for tailored IVF?

The human follicular fluid (HFF) contains molecules and proteins that may affect follicle growth, oocyte maturation and competence acquiring. Despite the numerous studies, an integrated broad overview on biomolecular and patho/physiological processes that are proved or supposed to take place in HFF during folliculogenesis and oocyte development is still missing. In this review we report, for the first time, all the proteins unambiguously detected in HFF and, applying DAVID (Database for Annotation, Visualization and Integrated Discovery) and MetaCore bioinformatic resources, we shed new lights on their functional correlation, delineating protein patterns and pathways with reasonable potentialities for oocyte quality estimation in in vitro fertilisation (IVF) programs. Performing a rigorous PubMed search, we redacted a list of 617 unique proteins unambiguously-annotated as HFF components. Their functional processing suggested the occurrence in HFF of a tight and highly dynamic functional-network, which is balanced by specific effectors, primarily involved in extracellular matrix degradation and remodelling, inflammation and coagulation. Metalloproteinases, thrombin and vitamin-D-receptor/retinoid-X-receptor-alpha resulted as the main key factors in the nets and their differential activity may be indicative of ovarian health and oocyte quality. Despite future accurate clinical investigations are absolutely needed, the present analysis may provide a starting point for more accurate oocyte quality estimation and for defining personalised therapies in reproductive medicine.

Association of vitamin D receptor gene polymorphisms with polycystic ovary syndrome among Indian women

Background & objectives:

The Vitamin-D receptor (VDR) regulates vitamin D levels and calcium metabolism in the body and these are known to be associated with endocrine dysfunctions, insulin resistance and type-2 diabetes in polycystic ovarian syndrome (PCOS). Studies on VDR polymorphisms among PCOS women are sparse. We undertook this study to investigate the association pattern of VDR polymorphisms (Cdx2, Fok1, Apa1 and Taq1) with PCOS among Indian women.

Methods:

For the present study, 250 women with PCOS and 250 normal healthy control women were selected from Hyderabad city, Telangana, India. The four VDR polymorphisms were genotyped and analysed using ASM-PCR (allele specific multiple PCR) and PCR-RFLP (restriction fragment length polymorphism).

Results:

The genotype and allele frequency distributions of only Cdx2 showed significant difference between the PCOS cases and control women, indicating protective role of this SNP against PCOS phenotype. However, significant association was observed between VDR genotypes and some of the PCOS specific clinical/biochemical traits. For example, Fok1 showed a significant genotypic difference for the presence of infertility and Cdx2 genotpes showed association with testosterone levels. Further, the two haplotypes, ACCA and ACTA, were found to be significantly associated with PCOS indicating haplotype specific risk.

Interpretation & conclusions:

Although VDR polymorphisms have not shown significant association with PCOS, in view of functional significance of the SNPs considered, one cannot yet rule out the possibility of their association with PCOS. Further, specifically designed studies on large cohorts are required to conclusively establish the role of VDR polymorphisms in PCOS, particularly including data on vitamin D levels.

Association of Vitamin D with outcome after intra cytoplasmic sperm injection

OBJECTIVE

To observe effects of vitamin D levels on pregnancy outcome after intra cytoplasmic sperm injection (ICSI).

METHOD

It was a cross-sectional study conducted in Australian Concept Infertility Medical Center from July 2011 to August 2014. Estimation of 25-hydroxy cholecalciferol (25-OHD) of consented females (252) was done before treatment protocol for ICSI. Results of β hCG performed 14 days after embryo transfer categorized groups; Pregnant with ß hCG more than 25 IU/mL and rest included in non-pregnant group. Both groups were compared by independent sample t-test and Pearson's Chi Square test. Binary Logistic Regression Analysis was used to estimate odds ratio of pregnancy outcome with its predictors including Vitamin D.

RESULTS

The mean value of 25-OHD, number of oocytes, fertilized oocytes and endometrial thickness was significantly higher in pregnant women. A significant positive association of 25-OHD with clinical pregnancy and thickness of endometrium was observed. After adjustment with female age and BMI, positive association of vitamin D with endometrial thickness was observed.

CONCLUSION

Deficiency of 25-OHD in females hinders the accomplishment of optimal endometrial thickness required for implantation of embryo after ICSI. The improvement in vitamin D status can thus improve success results in assisted reproductive clinics.

Vitamin D supplement improved testicular function in diabetic rats

This study was designed to investigate the role that 1,25(OH)2D3 plays against testicular lesion in diabetic rats and try to find its possible mechanism of the steroidogenesis and the spermatogenesis. In diabetic rats, prolonged hyperglycemia evaluated inflammatory cytokines, damaged sperm production function and redox balance, diminished serum testosterone. After treated with 1,25(OH)2D3 at two different doses respectively for 12 months, all the alternations were effectively normalized. 1,25(OH)2D3 showed inhibitory effect on excessive inflammatory biomarkers and adjusted the expression reproductive genes and testicular androgen synthesis. It also upregulated Bcl-2 expression, decreased Bax and COX-2 expression and inhibited active caspase cascade (caspase 8 and caspase 3), which may preserved the testicular cells under diabetic condition. It revealed that vitamin D supplement may protect the cells through suppressing inflammation factors and alleviating cell apoptotic death, as well as upregulating the expression of genes related to reproductive and testosterone synthesis.

Increasing serum 25-hydroxyvitamin D is associated with reduced odds of long menstrual cycles in a cross-sectional study of African American women

OBJECTIVE

To examine the association between serum 25-hydroxyvitamin D [25(OH)D] and menstrual cycle length and regularity.

DESIGN

Community-based, cross-sectional study of serum 25(OH)D (adjusted for seasonal differences in timing of blood draw) and menstrual cycle length. Women aged 23-34 years reported their gynecologic history. Menstrual cycles were described with four independent categories (normal, short, long, irregular). We used polytomous logistic regression to estimate the association between a doubling of seasonally adjusted 25(OH)D and the odds of each cycle category.

SETTING

Not applicable.

PATIENT(S)

A total of 1,102 African American women.

INTERVENTION(S)

Not applicable.

MAIN OUTCOME MEASURE(S)

Self-reported menstrual cycle length over the previous 12 months, excluding women who were using cycle-regulating medications over the entire year. Women who reported that their cycles were "too irregular to estimate" were classified as having irregular cycles. A typical cycle length of <27 days was considered "short," >34 days was "long," and 27-34 days was "normal."

RESULT(S)

The median 25(OH)D level was 14.7 ng/mL (interquartile range, 10.9-19.6 ng/mL). A doubling of 25(OH)D was associated with half the odds of having long menstrual cycles: adjusted odds ratio (aOR) 0.54, 95% confidence interval (CI) 0.32-0.89. 25-Hydroxyvitamin D was not associated with the occurrence of short (aOR 1.03, 95% CI 0.82-1.29) or irregular (aOR 1.46, 95% CI 0.88-2.41) menstrual cycles. Results were robust to several sensitivity analyses.

CONCLUSION(S)

These findings suggest that vitamin D status may influence the menstrual cycle and play a role in ovarian function. Further investigation of 25(OH)D and ovarian hormones, and prospective studies of 25(OH)D and cycle length, are needed.

Impact of hypovitaminosis D on clinical, hormonal and insulin sensitivity parameters in normal body mass index polycystic ovary syndrome women

Earlier data on the relationship of 25 hydroxyvitamins (25OHD) levels with various components of polycystic ovary syndrome (PCOS) has been conflicting. We studied 122 normal body mass index (BMI) women with PCOS (cases) and 46 age and BMI-matched healthy women (controls) and assessed the impact of serum 25OHD levels on clinical, biochemical and insulin sensitivity parameters in these lean Indian women with PCOS. The mean age and BMI of the cases and controls were comparable. Mean serum 25OHD levels respectively were 10.1 ± 9.9 and 7.9 ± 6.8 ng/ml with 87.7% and 91.1% vitamin D (VD) deficient. No significant correlation was noted between 25OHD levels and clinical, biochemical and insulin sensitivity parameters except with the total testosterone levels (p = 0.007). Also, no significant difference in these parameters was observed once the PCOS women were stratified into various subgroups based on the serum 25OHD levels. We conclude that VD deficiency being common in normal BMI Indian women with or without PCOS does not seem to alter the metabolic phenotype in these women.

Vitamin D status predicts reproductive fitness in a wild sheep population

Vitamin D deficiency has been associated with the development of many human diseases, and with poor reproductive performance in laboratory rodents. We currently have no idea how natural selection directly acts on variation in vitamin D metabolism due to a total lack of studies in wild animals. Here, we measured serum 25 hydroxyvitamin D (25(OH)D) concentrations in female Soay sheep that were part of a long-term field study on St Kilda. We found that total 25(OH)D was strongly influenced by age, and that light coloured sheep had higher 25(OH)D₃ (but not 25(OH)D₂) concentrations than dark sheep. The coat colour polymorphism in Soay sheep is controlled by a single locus, suggesting vitamin D status is heritable in this population. We also observed a very strong relationship between total 25(OH)D concentrations in summer and a ewe’s fecundity the following spring. This resulted in a positive association between total 25(OH)D and the number of lambs produced that survived their first year of life, an important component of female reproductive fitness. Our study provides the first insight into naturally-occurring variation in vitamin D metabolites, and offers the first evidence that vitamin D status is both heritable and under natural selection in the wild.

Late-onset hypogonadism: the advantages of treatment with human chorionic gonadotropin rather than testosterone

The traditional pharmacological treatment of patients with late onset hypogonadism (LOH) is represented by different formulations of testosterone (T) or alternatively by the extractive human chorionic gonadotropin (HCG). The hormone replacement treatment (HRT) is associated with the potential increase of hematocrit, serum concentrations of prostate-specific antigen (PSA) and prostate volume. Moreover, the gynecomastia represent a condition frequently associated with HRT. Recent evidences showed the role of leydig cells in the 25-hydroxylation of vitamin D and the elevated frequency of hypovitaminosis D among LOH patients. Finally, another important aspect of LOH is represented by the frequency of secondary infertility due to age or to traditional HRT. This study evaluated 40 LOH patients treated for 6 months with extractive HCG (n = 10 patients) and three different formulations of T: transdermal (n = 10 patients), undecaonate (n = 10 patients) and enantate (n = 10 patients). Hormonal, anthropometric, metabolic and sperm parameters were evaluated and compared. Moreover, the main safety parameters and the results of the main questionnaires were evaluated. After treatment, HCG group showed serum concentrations of 25-OH-vitamin D significantly higher (p < 0.05) and serum concentrations of oestrogens significantly lower (p < 0.05) compared with other groups. Moreover, they showed a mean value of hematocrit, PSA and prostate volume significantly lower (p < 0.05) compared with other groups. Finally, all the groups treated with T showed a significant reduction (p < 0.05) of sperm density and of percentage of spermatozoa with progressive motility compared with HCG group.

Effect of combined oral contraceptive use on serum 25-hydroxy vitamin D levels and ultrasound parameters in patients with polycystic ovary syndrome

PURPOSE

To investigate if there is an effect of combined oral contraceptive (COC) use on serum 25-hydroxy vitamin D [25(OH)D] levels in patients with polycystic ovary syndrome (PCOS).

METHODS

PCOS was defined by the 2003 Rotterdam criteria. All patients with PCOS were treated with a COC containing 0.035 mg ethinylestradiol and 2 mg cyproterone acetate for 6 months. Serum 25(OH)D levels, HOMA-IR, ovarian volume and antral follicule count were measured before and after the treatment.

RESULTS

The median 25(OH)D levels were 9.40 (range 4.40-24.50) μg/l and 7.00 (5.00-13.50) μg/l before and after COC use, respectively. Serum 25(OH)D levels decreased after the treatment; however, the difference was not statistically significant (p = 0.055).

CONCLUSION

This study seems to be the first prospective trial revealing the effect of COC use on serum 25(OH)D levels in women with PCOS. Although the decrease in serum 25(OH)D levels in patients with PCOS with the use of COC alone, did not reach to statistically significance level after 6 months treatment with COC.

Calcium plus vitamin D supplementation influences biomarkers of inflammation and oxidative stress in overweight and vitamin D-deficient women with polycystic ovary syndrome: a randomized double-blind placebo-controlled clinical trial

OBJECTIVE

This study was conducted to determine the effects of calcium plus vitamin D supplementation on inflammatory factors and biomarkers of oxidative stress among overweight vitamin D-deficient women with polycystic ovary syndrome (PCOS).

DESIGN, PATIENTS AND MEASUREMENTS

This randomized double-blind placebo-controlled clinical trial was performed among 104 overweight vitamin D-deficient women diagnosed with PCOS aged 18-40 years. Participants were randomly divided into four groups. Group A received 1000 mg calcium daily and vitamin D placebo weekly (N = 26), group B 50000 IU vitamin D weekly and calcium placebo daily (N = 26), group C 1000 mg calcium daily plus 50000 IU vitamin D weekly (N = 26) and group D calcium placebo daily plus vitamin D placebo weekly (N = 26) for 8 weeks. Fasting blood samples were taken at baseline and 8 weeks after intervention to measure inflammatory factors and biomarkers of oxidative stress.

RESULTS

After 8 weeks, individuals taking calcium plus vitamin D supplements had greater decreases in homoeostatic model assessment beta-cell function (HOMA-B) score (-11·1 vs -8·6, -3·4 and 13·7, respectively, P = 0·03), serum high-sensitivity C-reactive protein (hs-CRP) (-948·3 vs 802·3, -383·8 and 618·2 ng/ml, respectively, P = 0·04) and plasma malondialdehyde (MDA) concentrations (-0·6 vs -0·5, -0·1 and 0·6 μmol/l, respectively, P = 0·009), and significant increases in plasma total antioxidant capacity (TAC) (35·2 vs 21·1, 22·5 and -153·8 mmol/l, respectively, P = 0·006) and glutathione (GSH) levels (216·0 vs 3·9, -47·5 and -160·8 μmol/l, respectively, P = 0·001) compared with calcium alone, vitamin D alone and placebo groups. Calcium plus vitamin D cosupplementation did not influence plasma NO and catalase levels.

CONCLUSIONS

We found that calcium plus vitamin D cosupplementation for 8 weeks among overweight and vitamin D-deficient women with PCOS had beneficial effects on inflammatory factor and biomarkers of oxidative stress.

Association between serum 25-hydroxyvitamin D and ovarian reserve in premenopausal women

OBJECTIVE

Vitamin D has been linked to antimüllerian hormone levels, suggesting a possible association with greater ovarian reserve, but large population-based studies are lacking. Our objective was to explore the association between vitamin D and follicle-stimulating hormone (FSH) in premenopausal women.

METHODS

The Uterine Fibroid Study (1996-1999) enrolled randomly selected 30- to 49-year-old members of a Washington, DC, health plan (N = 1,430). Women provided blood and urine samples in addition to questionnaire data. The vitamin D metabolite 25-hydroxyvitamin D (25(OH)D) was measured in stored plasma samples. Urinary FSH (mIU/mg creatinine) was measured by immunofluorometric assay. To obtain baseline measures, we limited this investigation to urine samples collected in the first 5 days of the menstrual cycle or 5 days before menses onset. In addition, postmenopausal women and women using oral contraceptives were excluded, leaving 527 women for analysis. FSH was creatinine-adjusted, normalized by log transformation, and modeled with multivariable linear regression.

RESULTS

The median 25(OH)D level was 12 ng/mL, with approximately 75% of participants below the recommended level of 20 ng/mL. FSH and 25(OH)D were inversely related. For every 10-ng/mL increase in 25(OH)D, urinary FSH decreased by 14% (95% CI, -23 to -5; P = 0.003).

CONCLUSIONS

Vitamin D is inversely related to FSH. This is consistent with literature relating low vitamin D levels to lower antimüllerian hormone levels. Prospective studies should investigate whether low vitamin D levels contribute to decreased ovarian reserve.

Vitamin D Deficiency among Adolescent Females with Polycystic Ovary Syndrome

STUDY OBJECTIVE

Studies have suggested that low vitamin D levels may play a role in the pathogenesis of polycystic ovary syndrome (PCOS). The aim of our study was to compare 25-hydroxyvitamin D [25(OH)D] levels in adolescent females with and without PCOS.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective chart review at a tertiary care medical center for female adolescents aged 12-21 years with serum 25(OH)D measurements within a 5-year period. Participants were categorized as having PCOS or as controls based on National Institutes of Health PCOS diagnostic criteria.

MAIN OUTCOME MEASURE

Exact logistic regression analysis was done to compare normal (≥30 ng/mL) vs low (<30 ng/mL) serum 25(OH)D levels in the PCOS and control groups.

RESULTS

Two hundred ninety-nine charts were reviewed and 107 participants were included in the study. Of the included participants, 37 were in the PCOS group and 70 were in the control group, with a mean age of 15.2 years. In the PCOS group, 97.2% were obese and vitamin D deficiency was noted among 62.2% females. The mean serum 25(OH)D level was 18.4 and 21.6 ng/mL in PCOS and control groups, respectively. The difference in mean 25(OH)D levels between the 2 groups was not statistically significant (P > .05) when controlled for ethnicity, body mass index percentile, and season.

CONCLUSION

In our study, there was no statistically significant difference in mean 25(OH)D levels between PCOS and control groups. The majority of participants in PCOS group were obese. Further studies in adolescent females with PCOS and normal body mass index could be helpful in delineating the role of vitamin D in the pathogenesis of PCOS.

Vitamin D insufficiency is associated with increased risk of first-trimester miscarriage in the Odense Child Cohort

BACKGROUND

Miscarriage is the most common negative outcome of pregnancy, and identification of modifiable risk factors is potentially of great importance for public health. Low vitamin D concentrations in pregnancy are widespread worldwide, and vitamin D deficiency is implicated in immune cell regulation at the feto-maternal interface and several diseases of pregnancy.

OBJECTIVE

We investigated whether 25-hydroxyvitamin D serum concentration was a modifiable risk factor for early miscarriage.

DESIGN

In a prospective cohort study of 1683 pregnant women donating serum before gestational week 22, we investigated the association between maternal serum concentrations of serum 25-hydroxyvitamin D [25(OH)D] and the risk of subsequent miscarriage (n = 58).

RESULTS

The adjusted hazard of first-trimester miscarriage was lower with higher 25(OH)D concentrations (HR: 0.98; 95% CI: 0.96, 0.99). Concentrations of 25(OH)D <50 nmol/L were associated with a >2-fold increased adjusted HR for miscarriage (HR: 2.50; 95% CI: 1.10, 5.69). Concentrations of 25(OH)D were not associated with an increased risk of second-trimester miscarriage.

CONCLUSIONS

We found an association between 25(OH)D and first-trimester miscarriages, suggesting vitamin D as a modifiable risk factor for miscarriage. To test this hypothesis, randomized controlled trials should investigate the possible effect of vitamin D supplementation to increase 25(OH)D concentrations in early pregnancy, or before conception, to decrease risk of miscarriage. This trial was registered at clinicaltrials.gov as NCT02434900.

Effects of bariatric surgery on male obesity-associated secondary hypogonadism: comparison of laparoscopic gastric bypass with restrictive procedures

Bariatric surgery results in the complete resolution of male obesity-associated secondary hypogonadism (MOSH) in many patients. However, the effects of different bariatric surgical procedures on male sexual hormone profiles and sexual dysfunction have not been compared to date. We compared the pre- and post-operative (at least 6 months after initial surgery) sex hormone profiles of 20 severely obese men submitted to laparoscopic gastric bypass (LGB) with 15 similar patients submitted to restrictive techniques (sleeve gastrectomy in 10 and adjustable gastric banding in 5). We calculated free testosterone (FT) levels from total testosterone (TT) and sex hormone binding globulin (SHBG) concentrations. Fasting glucose and insulin levels served for homeostatic model assessment of insulin resistance (HOMAIR). MOSH was present in 25 and 16 of the 35 patients when considering TT and FT concentrations respectively, resolving after surgery in all but one of them. When considering all obese men as a whole, patients submitted to LGB or restrictive procedures did not differ in terms of excess weight loss, in the decrease of fasting glucose and insulin, HOMAIR and waist circumference, or in the increase of serum 25-hydroxyvitamin D, TT and FT levels. The improvement in TT correlated with the decrease in fasting glucose (r = -0.390, P = 0.021), insulin (r = -0.425, P = 0.015) and HOMAIR (r = -0.380, P = 0.029), and with the increase in SHBG (r = 0.692, P < 0.001). The increase in FT correlated with the decrease in fasting glucose (r = -0.360, P = 0.034). LGB and restrictive techniques are equally effective in producing a remission of MOSH.

Vitamin D supplementation and testosterone concentrations in male human subjects

OBJECTIVE

A possible association between serum 25-hydroxyvitamin D and testosterone levels has been reported; however, contradictory results have emerged.

DESIGN

To investigate a causal link between vitamin D and testosterone status, we studied the effect of vitamin D supplementation on serum testosterone concentrations in three independent intervention studies including male patients with heart failure (study 1), male nursing home residents (study 2) and male non-Western immigrants in the Netherlands (study 3).

METHODS

In study 1, 92 subjects were randomized to either vitamin D (2000 IU cholecalciferol daily) or control. Blood was drawn at baseline, after 3 and 6 weeks. In study 2, 49 vitamin D deficient subjects received either vitamin D (600 IU daily) or placebo. Blood was drawn at baseline, after 8 and 16 weeks. In study 3, 43 vitamin D deficient subjects received either vitamin D (1200 IU daily) or placebo. Blood was drawn at baseline, after 8 and 16 weeks. Serum 25-hydroxyvitamin D levels were measured using LC-MS/MS or radioimmunoassay. Testosterone levels were measured using a 2nd generation immunoassay.

RESULTS

Serum 25-hydroxyvitamin D levels significantly increased in all treatment groups (median increase of 27, 30 and 36 nmol/l in studies 1, 2 3, respectively) but not in the control groups. The documented increase in 25-hydroxyvitamin D levels, however, did not affect mean testosterone concentrations at the end of the study (median increase of 0, 0.5 and 0 nmol/l in studies 1, 2 and 3, respectively).

CONCLUSIONS

In this post hoc analysis of three small clinical trials of limited duration in men with normal baseline testosterone concentrations, vitamin D supplementation was not associated with an increase in circulating testosterone concentrations.

Lower plasma 25-hydroxyvitamin D is associated with irregular menstrual cycles in a cross-sectional study

BACKGROUND

In animals, low levels of vitamin D are associated with estrus cycle disturbances, but there are virtually no human data. We examined the association of 25-hydroxyvitamin D (25(OH)D) (a biomarker for vitamin D status) with menstrual cycle characteristics.

METHODS

Women aged 35-44 were randomly selected from a Washington D.C. health plan and invited to participate in the Uterine Fibroid Study (1996-1999). Our analysis includes 636 women (57% were African-American) who provided a blood sample and completed a telephone interview that included gynecologic history. Women were asked their usual cycle length in the preceding year. Women who reported it was "too irregular to estimate" were classified as having irregular cycles (N=48). Women were excluded if they currently or recently used hormonal contraception or any other medication that influences menstrual cycles. 25(OH)D was measured by radioimmunoassay in stored plasma samples.

RESULTS

The median 25(OH)D level was 12.0 ng/mL (interquartile range: 7.6, 19.7 ng/mL). After controlling for age, race, BMI, education, age of menarche, current smoking, alcohol use, and physical activity, a decrease in 25(OH)D of 10 ng/mL was associated with 1.9 times the odds of irregular cycles (Odds ratio (OR) (95% confidence interval (CI)): 1.9 (1.0, 3.4), p=0.04). 25(OH)D was not associated with the occurrence of short cycles (OR(CI): 1.08 (0.79, 1.48, p=0.6) or long cycles (OR(CI): 1.31 (0.66, 2.60), p=0.4).

CONCLUSIONS

Lower levels of 25(OH)D were associated with irregular cycles, but not with short or long cycles. Vitamin D may play a role in regulating ovulatory function. Further investigation of potential mechanisms is warranted.

Vitamin D and female fertility

PURPOSE OF REVIEW

Apart from the well known effects of vitamin D on maintaining calcium homeostasis and promoting bone mineralization, there is some evidence suggesting that vitamin D also modulates human reproductive processes. We will review the most interesting and relevant studies on vitamin D and female fertility published over the past year.

RECENT FINDINGS

In the past year, several observational studies reported a better in-vitro fertilization outcome in women with sufficient vitamin D levels (≥30 ng/ml), which was mainly attributed to vitamin D effects on the endometrium. One randomized controlled trial found an increased endometrial thickness in women with polycystic ovary syndrome (PCOS) receiving vitamin D during intrauterine insemination cycles. Further, vitamin D supplementation had a beneficial effect on serum lipids in PCOS women. Vitamin D treatment improved endometriosis in a rat model and increased vitamin D intake was related to a decreased risk of incident endometriosis. Vitamin D was also favorably associated with primary dysmenorrhea, uterine leiomyoma, and ovarian reserve in late reproductive aged women.

SUMMARY

In women undergoing in-vitro fertilization, a sufficient vitamin D level (≥30 ng/ml) should be obtained. Vitamin D supplementation might improve metabolic parameters in women with PCOS. A high vitamin D intake might be protective against endometriosis.

Classic PCOS phenotype is not associated with deficiency of endogenous vitamin D and VDR gene polymorphisms rs731236 (TaqI), rs7975232 (ApaI), rs1544410 (BsmI), rs10735810 (FokI): a case-control study of lower Silesian women

CONTEXT

The role of endogenous vitamin D and vitamin D receptor (VDR) gene polymorphism in polycystic ovary syndrome (PCOS) is still controversial.

OBJECTIVE

The objective of this study was to investigate for the first time in women with "classic" PCOS phenotype and healthy controls the role of the serum endogenous vitamin D level and VDR gene polymorphisms in PCOS etiology.

DESIGN

Ninety-two women with "classic" PCOS phenotype and 85 controls from lower Silesia with comparable body mass index (BMI) were studied. In all women the waist circumference, android/gynoid fat deposit, parameters of lipid and glucose metabolism, testosterone, free androgen index, sex hormone binding globulin (SHBG) and vitamin D were evaluated. Also, VDR gene polymorphisms rs731236, rs7975232, rs1544410 and rs10735810 were assessed.

RESULTS

Serum vitamin D levels in both groups were comparable. Also high, comparable frequencies of hypovitaminosis and vitamin D deficiency in both groups were observed. Women with "classic" PCOS phenotype had statistically significantly higher values of all measured parameters, except serum SHBG and high-density lipoprotein (HDL)-cholesterol, which were lower. The frequency of VDR genotype polymorphism was also comparable in both groups.

CONCLUSIONS

For the first time, we show that endogenous vitamin D deficiency and VDR polymorphisms are not associated with homogeneous "classic" PCOS phenotype.

Mechanisms in endocrinology: thyroid and polycystic ovary syndrome

Thyroid disorders, especially Hashimoto's thyroiditis (HT), and polycystic ovary syndrome (PCOS) are closely associated, based on a number of studies showing a significantly higher prevalence of HT in women with PCOS than in controls. However, the mechanisms of this association are not as clear. Certainly, genetic susceptibility contributes an important part to the development of HT and PCOS. However, a common genetic background has not yet been established. Polymorphisms of the PCOS-related gene for fibrillin 3 (FBN3) could be involved in the pathogenesis of HT and PCOS. Fibrillins influence the activity of transforming growth factor beta (TGFβ). Multifunctional TGFβ is also a key regulator of immune tolerance by stimulating regulatory T cells (Tregs), which are known to inhibit excessive immune response. With lower TGFβ and Treg levels, the autoimmune processes, well known in HT and assumed in PCOS, might develop. In fact, lower levels of TGFβ1 were found in HT as well as in PCOS women carrying allele 8 of D19S884 in the FBN3 gene. Additionally, vitamin D deficiency was shown to decrease Tregs. Finally, high estrogen-to-progesterone ratio owing to anovulatory cycles in PCOS women could enhance the immune response. Harmful metabolic and reproductive effects were shown to be more pronounced in women with HT and PCOS when compared with women with HT alone or with controls. In conclusion, HT and PCOS are associated not only with respect to their prevalence, but also with regard to etiology and clinical consequences. However, a possible crosstalk of this association is yet to be elucidated.

Effects of calcitriol on bone mineral density in patients treated with esomeprazole

CONTEXT

Proton pump inhibitor (PPI) increases the risk of decrease in bone mineral density (BMD). However, whether calcitrol improves this situation is unknown.

OBJECTIVE

The current study investigates the effects of calcitriol on BMD in patients with esomeprazole therapy.

MATERIALS AND METHODS

Three hundred and eighty-six participants with gastrointestinal ulcerations were enrolled and randomly assigned into controlled and supplemented groups. Participants in the controlled group were prescribed esomeprazole (20 mg/qd), while the supplemented group was prescribed esomeprazole (20 mg/qd) and calcitriol (2.5 μg/qd). BMD, serum levels of calcium, carboxy-terminal collagen crosslinks (CTX), and alkaline-phosphatase (ALP) were assessed.

RESULTS

(1) No significant between-group difference of age, gender, smoking, previous glucocorticoid use and hemoglobin level was found; (2) after 10.6 ± 0.8 d of PPI therapy, BMD T score in the controlled group was slightly increased compared with initial (-1.25 ± 0.08 versus -1.28 ± 0.06, p = 0.084), while there was no change in the supplemented group (-1.25 ± 0.05 versus -1.26 ± 0.03, p = 0.308); (3) during study termination, calcium level in the supplemented group was slightly higher than the controlled group (2.05 ± 0.03 mmol/L versus 2.01 ± 0.05 mmol/L, p = 0.073), while no significant differences of CTX (366.57 ± 43.71 pg/mL versus 373.15 ± 50.23 pg/mL, p = 0.036) and ALP were found among these two groups (50.47 ± 9.32 U/L versus 52.23 ± 10.45 U/L, p = 0.075).

CONCLUSION

Patients with gastrointestinal ulcerations with esomeprazole therapy, calcitriol supplement showed no efficacy on BMD changes.

Insulin and body weight but not hyperandrogenism seem involved in seasonal serum 25-OH-vitamin D3 levels in subjects affected by PCOS

PCOS patients were frequently characterized by lower plasma vitamin D levels. The mechanisms involved in this dysfunction remains still debated, therefore we evaluated the role of androgen, insulin and body weight on the serum VitD levels in women with or without PCOS. Eighty one patients 18-42 yrs old were studied into "SUMMER" and "WINTER" seasonal period: thirty seven PCOS, seventeen no-ovarian hyperandrogenic (noPCOS), twelve functional hypothalamic amenorrhea (FHA) and finally fifteen healthy (Con). Patients were further divided into: lean (L), obese (O), normo- (nINS) and hyperinsulinemic (hINS). All hormonal and metabolic parameters were measured at 1-7 days of the menstrual cycle. Our results show that VitD levels were lower in PCOS and in noPCOS than in FHA and Con, in particular in (O) and (hINS) PCOSs. Both in summer and in winter, PCOSs had basal VitD levels significantly lower than FHA and Con, whereas they were similar to noPCOS. Yet, LhINS and OPCOS had VitD levels lower than Con and noPCOS. VitD levels were comparable in LnINS PCOS and Con. In conclusion, PCOSs had levels of VitD lower than controls. Weight and hyperinsulinemia had a significant influence on these values. Finally, over 70% of our healthy patients had VitD deficiency.

1,25-Dihydroxyvitamin D3 increases testosterone-induced 17beta-estradiol secretion and reverses testosterone-reduced connexin 43 in rat granulosa cells

BACKGROUND

Aromatase converts testosterone into 17beta-estradiol in granulosa cells, and the converted 17beta-estradiol contributes to follicular maturation. Additionally, excessive testosterone inhibits aromatase activity, which can lead to concerns regarding polycystic ovary syndrome (PCOS). Generally, 1,25-dihydroxyvitamin D3 (1,25D3) supplements help to improve the symptoms of PCOS patients who exhibit low blood levels of 1,25D3. Therefore, this study investigated the interaction effects of 1,25D3 and testosterone on estrogenesis and intercellular connections in rat granulosa cells.

METHODS

Primary cultures of granulosa cells were treated with testosterone or testosterone plus 1,25D3, or pre-treated with a calcium channel blocker or calcium chelator. Cell lysates were subjected to western blot analysis to determine protein and phosphorylation levels, and 17beta-estradiol secretion was examined using a radioimmunoassay technique. Cell viability was evaluated by MTT reduction assay. Connexin 43 (Cx43) mRNA and protein expression levels were assessed by qRT-PCR, western blot, and immunocytochemistry.

RESULTS

Testosterone treatment (0.1 and 1 microg/mL) increased aromatase expression and 17beta-estradiol secretion, and the addition of 1,25D3 attenuated testosterone (1 microg/mL)-induced aromatase expression but improved testosterone-induced 17beta-estradiol secretion. Furthermore, testosterone-induced aromatase phosphotyrosine levels increased at 10 min, 30 min and 1 h, whereas 1,25D3 increased the longevity of the testosterone effect to 6 h and 24 h. Within 18-24 h of treatment, 1,25D3 markedly enhanced testosterone-induced 17beta-estradiol secretion. Additionally, pre-treatment with a calcium channel blocker nifedipine or an intracellular calcium chelator BAPTA-AM reduced 1,25D3 and testosterone-induced 17beta-estradiol secretion. Groups that underwent testosterone treatment exhibited significantly increased estradiol receptor beta expression levels, which were not affected by 1,25D3. Neither testosterone nor 1,25D3 altered 1,25D3 receptor expression. Finally, at high doses of testosterone, Cx43 protein expression was decreased in granulosa cells, and this effect was reversed by co-treatment with 1,25D3.

CONCLUSIONS

These data suggest that 1,25D3 potentially increases testosterone-induced 17beta-estradiol secretion by regulating aromatase phosphotyrosine levels, and calcium increase is involved in both 1,25D3 and testosterone-induced 17beta-estradiol secretion. 1,25D3 reverses the inhibitory effect of testosterone on Cx43 expression in granulosa cells.

Small non-coding RNA profiling and the role of piRNA pathway genes in the protection of chicken primordial germ cells

BACKGROUND

Genes, RNAs, and proteins play important roles during germline development. However, the functions of non-coding RNAs (ncRNAs) on germline development remain unclear in avian species. Recent high-throughput techniques have identified several classes of ncRNAs, including micro RNAs (miRNAs), small-interfering RNAs (siRNAs), and PIWI-interacting RNAs (piRNAs). These ncRNAs are functionally important in the genome, however, the identification and annotation of ncRNAs in a genome is challenging. The aim of this study was to identify different types of small ncRNAs particularly piRNAs, and the role of piRNA pathway genes in the protection of chicken primordial germ cells (PGCs).

RESULTS

At first, we performed next-generation sequencing to identify ncRNAs in chicken PGCs, and we performed ab initio predictive analysis to identify putative piRNAs in PGCs. Then, we examined the expression of three repetitive sequence-linked piRNAs and 14 genic-transcript-linked piRNAs along with their linked genes using real-time PCR. All piRNAs and their linked genes were highly expressed in PGCs. Subsequently, we knocked down two known piRNA pathway genes of chicken, PIWI-like protein 1 (CIWI) and 2 (CILI), in PGCs using siRNAs. After knockdown of CIWI and CILI, we examined their effects on the expression of six putative piRNA-linked genes and DNA double-strand breakage in PGCs. The knockdown of CIWI and CILI upregulated chicken repetitive 1 (CR1) element and RAP2B, a member of RAS oncogene family, and increased DNA double-strand breakage in PGCs.

CONCLUSIONS

Our results increase the understanding of PGC-expressed piRNAs and the role of piRNA pathway genes in the protection of germ cells.