Vitamin D and the brain

The relationships of vitamin D, vitamin D receptor gene polymorphisms, and vitamin D supplementation with Parkinson's disease

In recent years, many studies have investigated the correlations between Parkinson's disease (PD) and vitamin D status, but the conclusion remains elusive. The present review focuses on the associations between PD and serum vitamin D levels by reviewing studies on the associations of PD with serum vitamin D levels and vitamin D receptor (VDR) gene polymorphisms from PubMed, Web of Science, Cochrane Library, and Embase databases. We found that PD patients have lower vitamin D levels than healthy controls and that the vitamin D concentrations are negatively correlated with PD risk and severity. Furthermore, higher vitamin D concentrations are linked to better cognitive function and mood in PD patients. Findings on the relationship between VDR gene polymorphisms and the risk of PD are inconsistent, but the FokI (C/T) polymorphism is significantly linked with PD. The occurrence of FokI (C/T) gene polymorphism may influence the risk, severity, and cognitive ability of PD patients, while also possibly influencing the effect of Vitamin D3 supplementation in PD patients. In view of the neuroprotective effects of vitamin D and the close association between vitamin D and dopaminergic neurotransmission, interventional prospective studies on vitamin D supplementation in PD patients should be conducted in the future.

Vitamin D and Hyperkinetic Movement Disorders: A Systematic Review

Background

The importance of vitamin D deficiency in Parkinson's disease, its negative influence on bone health, and even disease pathogenesis has been studied intensively. However, despite its possible severe impact on health and quality of life, there is not a sufficient understanding of its role in other movement disorders. This systematic review aims at providing an overview of the prevalence of vitamin D deficiency, bone metabolism alterations, and fractures in each of the most common hyperkinetic movement disorders (HKMDs).

Methods

The study search was conducted through PubMed with keywords or Medical Related Subjects (MeSH) of common HKMDs linked with the terms of vitamin D, osteoporosis, injuries, and fractures.

Results

Out of 1585 studies screened 40 were included in our review. They show that there is evidence that several HKMDs, including Huntington disease, Restless Legs Syndrome, and tremor, are associated with low vitamin D serum levels in up to 83% and 89% of patients. Reduced bone mineral density associated with vitamin D insufficiency was described in Huntington disease.

Discussion

Our survey suggests that vitamin D deficiency, bone structure changes, and fractures are important but yet under-investigated issues in HKMDs. HKMDs-patients, particularly with a history of previous falls, should have their vitamin D-levels tested and supplemented where appropriate.

Highlights

Contrary to Parkinson's disease, vitamin D deficiency, and bone abnormalities are under-investigated in hyperkinetic movement disorders (HKMDs). Several HKMDs, including essential tremor, RLS, and Huntington disease, are associated with vitamin D deficiency in up to 89%, the latter also with reduced bone mineral density. Testing and where appropriate supplementation is recommended.

Vitamin D Megadose: Definition, Efficacy in Bone Metabolism, Risk of Falls and Fractures

Introduction

Currently, approximately more than one billion people around the world are considered to have deficient levels of vitamin D. International consensus recommends vitamin D supplementation to high-risk patients (advanced age, osteoporosis, liver failure, malabsorption syndromes, etc.) and those with levels below 30 ng/mL. There are several vitamin D formulations and dosages available, including megadoses. At the moment, there is no consensus on the definition of megadoses. The purpose of this review is to define what is a megadose and analyze its effectiveness in bone metabolism, risk of fractures and falls.

Conclusion

The administration of doses higher than 100,000 IU of vitamin D is considered a megadose. It is evident that the use of megadoses increases serum concentrations of vitamin D; however, there has been no evidence of a decrease in the risk of falls, vertebral fractures or changes in bone mineral density.

Vitamin D Status Is Not Associated with Cognitive or Motor Function in Pre-School Ugandan Children

Vitamin D deficiency is common worldwide and young children are among the most affected groups. Animal studies suggest a key role for vitamin D in brain development. However, studies investigating the effects of vitamin D on neurobehavioural outcomes in children are inconclusive and evidence is limited in sub-Saharan Africa. We evaluated the effect of vitamin D status on cognitive and motor outcomes using prospective data from the Entebbe Mother and Baby Study birth cohort. We analysed data from 302 Ugandan children with 25-hydroxyvitamin D (25(OH)D) measurements below five years and developmental measures at five years of age. We used multivariable linear regression, adjusted for potential confounders, to estimate the effect of 25(OH)D on cognitive and motor outcomes. Of 302 children, eight (2.7%) had 25(OH)D levels <50 nmol/L, 105 (35.8%) had levels 50-75 nmol/L and 189 (62.6%) had levels >75 nmol/L. There was no evidence that earlier vitamin D status was associated with cognitive and motor outcomes in five-year-old Ugandan children. This study adds to the sparse literature and highlights the need for further longitudinal studies on vitamin D and neurobehavioural outcomes in children living in sub-Saharan Africa.

Children's Health in the Digital Age

Environmental studies, metabolic research, and state of the art research in neurobiology point towards the reduced amount of natural day and sunlight exposure of the developing child, as a consequence of increasingly long hours spent indoors online, as the single unifying source of a whole set of health risks identified worldwide, as is made clear in this review of currently available literature. Over exposure to digital environments, from abuse to addiction, now concerns even the youngest (ages 0 to 2) and triggers, as argued on the basis of clear examples herein, a chain of interdependent negative and potentially long-term metabolic changes. This leads to a deregulation of the serotonin and dopamine neurotransmitter pathways in the developing brain, currently associated with online activity abuse and/or internet addiction, and akin to that found in severe substance abuse syndromes. A general functional working model is proposed under the light of evidence brought to the forefront in this review.

Differential Frequency of CYP2R1 Variants Across Populations Reveals Pathway Selection for Vitamin D Homeostasis

CONTEXT

Normal vitamin D homeostasis is necessary to ensure optimal mineral metabolism. Dietary insufficiency of vitamin D and the lack of sunlight each have well understood roles in vitamin D deficiency; however, the extent to which common genetic variations in vitamin D metabolizing enzymes contribute to alterations in vitamin D homeostasis remains uncertain.

OBJECTIVE

To examine the possibility that common coding variation in vitamin D metabolizing enzymes alters vitamin D homeostasis we determined the effect of 44 nonsynonymous polymorphisms in CYP2R1, the vitamin D 25-hydroxylase, on enzyme function.

RESULTS

Twenty-one of these polymorphisms decreased activity, while 2 variants increased activity. The frequency of CYP2R1 alleles with decreased 25-hydroxylase activity is 3 in every 1000 Caucasians and 7 in every 1000 African Americans. In populations where exposure to sunlight is high, alleles with decreased function occur at a frequency as high as 8%. The pattern of selected variation as compared to nonselected variation is consistent with it being the result of positive selection for nonfunctional alleles closer to the equator. To examine this possibility, we examined the variation pattern in another protein in the vitamin D pathway, the vitamin D binding protein (GC protein). The pattern of selected variation in the GC protein as compared to nonselected variation is also consistent with it being the result of positive selection for nonfunctional alleles closer to the equator.

CONCLUSIONS

CYP2R1 polymorphisms have important effects on vitamin D homeostasis, and the geographic variability of CYP2R1 alleles represents an adaptation to differential exposures to UVB irradiation from sunlight.

Vitamin D status among patients with drug-resistant and non-drug-resistant epilepsy

Background & Aims: Epilepsy affects nearly 70 million people worldwide. Vitamin D deficiency may influence the balance of certain epilepsies. The purpose of this study was to determine the vitamin D status and anthropometric measurements of people with epilepsy (PWE), according to their pharmacosensitivity. Methods: Forty-six PWE, with or without drug resistance, underwent nutritional assessment after giving consent. Weight, body mass index (BMI), triceps skinfold thickness (TSF), fat mass (FM) and free fat mass (FFM) by bioelectrical impedance analysis were measured. Serum vitamin D was determined without supplementation. Deficiency was defined as a level < 30 ng/mL. Statistical analysis involved Student t test, ANOVA and Chi². Results: Patients were aged 44.5 ± 14.3 years, with 60.9% of drug-resistance. BMI was 28.7 ± 7.0, 2.2% were malnourished and 30.4% obese according to the BMI. The average vitamin D level was 15.3 ± 9.9 ng/mL, with 87.0% of deficiency, and 40.0% of severe deficiency (<10 ng/mL). The TSF was higher in drug-resistant cases (p = 0.03). There was no link between drug resistance and anthropometric measurements, FM, FFM or vitamin D concentration. Conclusions: Although limited in size, this study showed that PWE are more often obese. Vitamin D deficiency is more common than in the general population, with a much higher prevalence of severe deficiency.

Vitamin D concentration and focal brain atrophy in older adults: a voxel-based morphometric study

Vitamin D is involved in brain health and function. Our objective was to determine whether lower 25‐hydroxyvitamin D (25OHD) concentration was associated with focal brain volume reduction in older adults. Serum 25OHD concentration was measured among 53 older adults (72 ± 5 years; 38% female; mean 25OHD = 67.3 ± 20.8 nmol/L). Gray matter volume (GMV) was automatically segmented using voxel‐based morphometry with CAT12 software. Covariables were age, gender, education, total intracranial volume, and season. Serum 25OHD was positively associated with GMV in left calcarine sulcus (P < 0.05, TFCE, FWE‐corrected). We found atrophy of the calcarine sulcus with lower 25OHD concentrations in older adults.

[Bipolar disorder vulnerability: The vitamin D path]

OBJECTIVES

Bipolar disorder (BD) etiopathogenesis is still not well elucidated. It has recently been proven that 25-hydroxy vitamin D (25OHD) has an anti-inflammatory and neuroprotective role. Our objectives were to measure 25OHD plasma levels in patients with BD in acute decompensation and compare them with patients with schizophrenia (SCZ) or schizoaffective disorder (SAD) and with healthy controls.

METHODS

This is a cross-sectional case-control study including male inpatients with a decompensation of their disease who were diagnosed with BD, SCZ or SAD according to DSM-5 criterias. The control group was constituted by unrelated healthy subjects, age-and-sex matched.

RESULTS

The 25OHD level was significantly higher only in patients with BD compared to controls. 25OHD was also positively correlated to the PANSS scale (r = 0.282, p < 0.001) and to different MOCA scores (r = 0.326, p = 0.006) as well as aspects related to abstraction, attention and memory capacity. Multivariate analysis found that BD acute decompensation was independently related to the rise in plasma 25OHD (p = 0.012; OR =1.157, [1.032 -1.297]).

CONCLUSION

Our study shows that BD acute decompensation is associated with the rise in plasma 25OHD synthesis. However, the vitamin D dosage relevance as a biomarker of this disease warrants a verification in other studies.

Vitamin D Deficiency During Pregnancy and Autism Spectrum Disorders Development

Autism spectrum disorder is a neurodevelopmental disorder characterized by reduced social interactions, impaired communications, and stereotypic and repetitive behavior with different degrees of severity. The etiology of autism spectrum disorder is unknown, although the interaction of genetic and environmental factors is believed to play a fundamental role in the process. The main aim of this narrative review is to discuss the current knowledge about the interrelationships between vitamin D deficiency during pregnancy and autism spectrum disorder development. Literature analysis showed that vitamin D supplementation during pregnancy plays a role in conditioning the development and function of the nervous system. Studies carried out in vitro and in experimental animals have shown that vitamin D deficiency can be associated with structural and functional abnormalities of the nervous system that can be observed in autism spectrum disorder patients. Moreover, it has been reported that vitamin D deficiency during pregnancy could be a risk factor for autism spectrum disorder development in the offspring, that children with autism spectrum disorder have significantly lower serum levels of vitamin D than normal children and that supplementation of vitamin D in autism spectrum disorder children is associated with a reduction in psychiatric manifestations. However, the data currently available do not adequately support the hypothesis that vitamin D may be a factor which contribute to the etiology of autism spectrum disorder. The effects of vitamin D supplementation during pregnancy should be better studied to establish whether and when fetal vulnerability is highest and if vitamin D supplementation is able to reduce the risk of structural and functional alterations of the nervous system and autism spectrum disorder development. The role of vitamin D after birth must be better defined to evaluate if vitamin D administration is potentially effective in reducing autism spectrum disorder manifestations.

Vitamin D deficiency is endemic in neurosurgical patients and is associated with a longer length of inpatient stay

INTRODUCTION

Vitamin D deficiency is common in spinal surgery and critical care. Hypovitaminosis D may impact on outcomes in cranial neurosurgical care and play roles in underlying disease processes.

METHODS

A prospective observational cohort study was performed. All emergency cranial neurosurgical ward admissions from 1st January to 10th May 2017 were screened for inclusion (n = 406). Patients already receiving vitamin D supplementation, spinal patients and elective admissions were excluded. Admission vitamin D levels were checked for all remaining patients (n = 95). Patients with vitamin D <30 nmol/L were defined as "deficient" and those 30-50 nmol/L as "inadequate." All patients with levels <50 nmol/L were replaced, as per local guidelines. Descriptive analyses of the cohorts were undertaken, with multivariate regression used to assess the effect of vitamin D on length of stay, inpatient morbidity and mortality.

RESULTS

The median age of participants was 61 years (n = 95; 57% male, 43% female). The median vitamin D level was 23 nmol/L (deficient). 84% (n = 80) of patients had low vitamin D levels, with 61% (n = 58) classed as deficient (<30 nmol/L). Vitamin D deficiency rates were similar in those aged below 65 years (86%; n = 38/44) and those above 65 years (82%; n = 42/51). Deficient vitamin D level was associated with longer hospital stay (P = .03), and this relationship persisted after adjusting for potential confounders such as age, sex and preadmission Charlson co-morbidity index. No statistically significant association was seen with vitamin D status and inpatient morbidity or mortality.

CONCLUSIONS

Vitamin D deficiency is common in cranial neurosurgical patients, even in predefined low-risk groups (age <65). Lower vitamin D level was associated with longer length of stay. This study supports the need for: (a) further investigation into the roles of vitamin D in neurosurgical pathologies and management and (b) an appropriately powered, randomised investigation into the impact of vitamin D status upon neurosurgical diagnoses and complications.

Implications of vitamin D toxicity & deficiency

Vitamin D deficiency is an increasing problem affecting all ages. Patients should be assessed for risk factors as part of preventive health maintenance. Vitamin D toxicity is a rare occurrence caused by oversupplementation and errors in food fortification. The connection between vitamin D deficiency and osteoporosis, is well established. However, a cause and effect relationship has yet to be established between vitamin D deficiency and many chronic illnesses. An evidence-based approach is treating patients for an underlying vitamin D deficiency in hopes of improving many chronic illnesses.

Relationship between 25-Hydroxyvitamin D, bone density, and Parkinson's disease symptoms

OBJECTIVES

Vitamin D deficiency is widespread in patients with Parkinson's disease (PD). Our aim was to determine whether serum vitamin D levels correlated with bone mineral density (BMD) and non-motor symptoms in patients with PD.

MATERIALS & METHODS

A consecutive series of 182 patients with PD and 185 healthy controls were included. Serum 25-hydroxyvitamin D (25[OH]D) levels were measured by immunoassay, while BMD of the lumbar spine and femoral neck was measured by dual-energy X-ray absorptiometry. Associations between serum vitamin D levels and clinical data were evaluated using partial correlation analysis.

RESULTS

Patients with PD had significantly lower serum 25(OH)D levels relative to healthy controls (49.75 ± 14.11 vs 43.40 ± 16.51, P < 0.001). Furthermore, PD patients with lower vitamin D levels had a significantly higher frequency of falls (P = 0.033) and insomnia (P = 0.015). They also had significantly higher scores for the Pittsburgh Sleep Quality Index (PSQI; P = 0.014), depression (P = 0.020), and anxiety (P = 0.009). Finally, patients with PD also had a significantly lower mean BMD of the lumbar spine (P = 0.011) and femoral neck (P < 0.001). After adjusting for age, sex, and body mass index, vitamin D levels significantly correlated with falls, insomnia, and scores for the PSQI, depression, and anxiety.

CONCLUSIONS

In patients with PD, vitamin D levels significantly correlated with falls and some non-motor symptoms. However, no associations were found between BMD and the serum 25(OH)D levels in patients with PD. Thus, vitamin D supplementation is a potential therapeutic for non-motor PD symptoms.

Cost-Effective HPLC-UV Method for Quantification of Vitamin D2 and D3 in Dried Blood Spot: A Potential Adjunct to Newborn Screening for Prophylaxis of Intractable Paediatric Seizures

25-Hydroxyvitamin D (25-(OH)D) deficiency is recently been described as one of the multiple factors responsible for pediatric seizures. 25-Hydroxyvitamin D3 and 25-Hydroxyvitamin D2 are the well-known markers to determine Vitamin D status. In this work we report the development of a sensitive and cost effective HPLC technique for the quantification of the vitamin D metabolites from dried blood spot samples (DBS). The metabolites were extracted using acetonitrile-methanol-0.1% formic acid (60 : 20 : 20 (v/v)) and analyzed on an Acclaim C₁₈ column (150 × 4.6 mm i.d., 3 µm) at a flow rate of 1 mL/min. The method was linear in the range of 10-80 ng/mL. Limit of detection and limit of quantification (LOQ) of the method were 5 and 10 ng/mL respectively. Extensive stability studies demonstrated the analytes to be stable in stock and matrix with a percent change within the acceptable range of ±15%. Comparison of the newly developed HPLC-DBS method with the reported LC-MS-DBS and electrochemiluminescence immunoassay (ECLIA) methods followed by Bland-Altman analysis demonstrated a bias of 0.08 and -0.14, respectively proving the methods are comparable. Application of the developed method to a pediatric seizure cohort depicted 46.6% of cases as deficient and 26.6% as insufficient for 25-(OH)D. Among deficient cases 8 samples were below 10 ng/mL and exact amount was not calculated since these were below the LOQ levels. The mean  ±  standard deviation (S.D.) in the remaining 6 deficient cases was 13.22 ± 2.80 ng/mL. The levels in healthy infants were 33.9 ± 6.11 ng/mL. The method can be used routinely for assessing 25-(OH)D deficiency in newborn.

Association of vitamin D nutrition with neuro-developmental outcome of infants of slums in Bangladesh

The association of vitamin D with neuro-behavioral outcomes of young children is unclear, particularly of those who reside in tropical countries and are otherwise exposed to adequate sun light. To investigate this association, we analysed the existing data of poor infants, who participated in an observational, prospective-cohort (MalED) study, conducted in a slum of Dhaka-city. We assessed 265 infants aged 6–8 months for cognitive, motor, language and behavior development using Bayley-III. Information about infants’ temperament and communicative skills were provided by the mothers through a culturally modified “temperament-scale” and a “communicative-developmental inventory”. Serum concentration of vitamin D [25(OH)D] was measured in 205 infants. Around 28.3% of infants in this community had low level vitamin D, with the cut-off at <50 nmol/L. After controlling for all possible covariates, a multivariable-adjusted linear regression showed that children with vitamin D levels <50 nmol/L had significantly lower scores in two dimensions of temperament: activity (B±SE 1.64±0.78; 95%CI 0.10, 3.18; p = 0.037; effect size 0.37 SDs) and soothabilty (2.02±0.70; 0.64, 3.41; p = 0.004; 0.53 SDs), compared to children with vitamin D levels of ≥50nmol/L. These infants also scored low in word comprehensions (1.28±0.62; 0.05, 2.51; p = 0.042; 0.23 SDs) and were less active during test-procedures (0.33±0.16; 0.02, 0.64; p = 0.035; 0.27 SDs). Both the groups tested similarly in cognitive and motor scores. This study found, despite adequate sunlight-exposure, one in four infants of this slum-community are suffering from a subclinical vitamin D deficiency. Higher levels of vitamin D in these infants showed a positive association with temperament, language and behavior but not with cognitive and motor development. Our findings highlight the early-detected extra-skeletal neuro-behavioral role of vitamin D. Future studies in this area will give more insight.

Vitamin D Deficiency and Neurologic Outcome After Sudden Cardiac Arrest

BACKGROUND

Vitamin D deficiency is related to various cardiovascular diseases, including sudden cardiac arrest (SCA). This study investigated the association of vitamin D level with neurologic outcome and mortality after resuscitation from SCA.

PATIENTS AND METHODS

We enrolled patients who were successfully resuscitated from out-of-hospital cardiac arrest of presumed cardiac cause in Severance Cardiovascular Hospital as a prospective cohort registry. Baseline blood samples including pH, lactate, and vitamin D were obtained without fluid replacement just after hospital admission. Outcome was assessed by cerebral performance category (CPC) score at 1 month after SCA. Favorable outcome was defined as survival with CPC score of 1 or 2, whereas unfavorable one as death or survival with CPC scores of 3 through 5. Severe vitamin D deficiency was defined as 25(OH)D <10 ng/mL.

RESULTS

A total of 163 patients were included. Overall 96 (59%) patients had a favorable neurologic outcome, whereas 67 patients (41%) showed unfavorable outcome, including 37 (23%) mortality. Patients with unfavorable outcome were likely to be female and have initial non-shockable rhythm, longer arrest time, severe shock, diabetes, and baseline renal dysfunction. In multivariate analysis, severe vitamin D deficiency was one of the poor prognostic factors of both unfavorable neurologic outcome and mortality after SCA.

CONCLUSIONS

Vitamin D deficiency is very prevalent and strongly associated with both unfavorable neurologic outcome and mortality in patients resuscitated from SCA.

Effects of Vitamin D3 in Long-Term Ovariectomized Rats Subjected to Chronic Unpredictable Mild Stress: BDNF, NT-3, and NT-4 Implications

The purpose of this study was to explore the antidepressant-like effects of vitamin D₃ at different doses (1.0, 2.5, and 5.0 mg/kg sc) on a model of depression produced by chronic unpredictable mild stress (CUMS) for 28 days in long-term (3 months) ovariectomized (OVX) adult rats. Sucrose preference (SPT), forced swimming (FST) and open-field (OFT) tests were conducted to examine the depression-like state. Serum corticosterone/adrenocorticotrophic hormone (ACTH) levels and hippocampal brain-derived neurotrophic factor (BDNF) and neurotrophin (NT)-3/NT-4 expressions by ELISA kits and/or western blotting were determined to assess the possible mechanisms of the vitamin D₃ effects on the depression-like profile in long-term OVX rats subjected to CUMS. The results showed that vitamin D₃ (5.0 mg/kg), as well as fluoxetine treatment, considerably reversed the depression-like state in the SPT and FST, decreased serum corticosterone/ACTH levels, and increased BDNF and NT-3/NT-4 levels in the hippocampus of long-term OVX rats compared to OVX rats with CUMS (p < 0.05). Thus, a high dose of vitamin D₃ (5.0 mg/kg sc) could improve the depression-like profile in long-term OVX adult female rats subjected to the CUMS procedure, which might be mediated by the regulation of BDNF and the NT-3/NT-4 signaling pathways in the hippocampus, as well as the corticosterone/ACTH levels of the blood serum.

Effects of vitamin D supplementation on depressive symptoms in type 2 diabetes mellitus patients: Randomized placebo-controlled double-blind clinical trial

AIM

Diabetes increases the odds of depression and depression is often associated with poor glycemic control and complications of diabetes. Vitamin D is also believed to improve glycemic control and ameliorate depressive symptoms. Therefore, we examined effects of vitamin D monotherapy (without antidepressant drugs) on depressive symptoms in Type 2 diabetic patients with mild to moderate depressive symptoms.

METHODS

We conducted 12 weeks, placebo-controlled, double-blind, randomized trial on 68 subjects with T2DM and mild to moderate depressive symptoms. Subjects received 100 μg (4000 IU) vitamin D (n = 32) or placebo (n = 34) daily. Beck Depression Inventory-II (BDI-II-PERSIAN) was applied for assessment of the severity of depression. Depression scores and metabolic profiles were measured at the beginning and end of trail.

RESULTS

after 3 months of vitamin D supplementation, mean values of 25(OH) D increased from 15.5 ± 8.8 to 32.2 ± 8.9 ng/ml (p-value <0.001) in the vitamin D group. Moreover, BDI-II scores decreased from 15.2 ± 9.6 to 9.8 ± 7.2 (p-value <0.001) in the vitamin D group and 15.5 ± 11.2 to 13.7 ± 11.5 (p-value = 0.03) in placebo group. This decrease in BDI-II scores were significant (27.6% vs 10.8%) compared with placebo (p-value = 0.02). In term of metabolic profiles, mean change in level of Hemoglobin A1c (HbA1c), insulin and triglycerides (TG) were significantly higher in response to the treatment with vitamin D compared to placebo (p-value <0.02).

CONCLUSIONS

In conclusion, supplementation of vitamin D in T2DM patients may protect these patients against the onset of major depressive disorder (MDD), with noticeable favorable effects on measures of metabolic profiles.

TRIAL REGISTRATION

NCT03008057.

Improvement in Cognition Following Double-Blind Randomized Micronutrient Interventions in the General Population

The impact of poor nutrition on physiological health is well understood (Costarelli et al., 2013). Less is known about the effects of diet on brain function and cognition in the general population (Ames, 2010; Parletta et al., 2013; White et al., 2017) and we are still in the early stages of understanding the role of specific nutrients to normal and pathological neuronal functioning. In the present study, the putative effect of a multivitamin/mineral or vitamin D supplement on cognitive function over an 8-week period was compared with volunteers taking vitamin C. Healthy adults (N = 60) were recruited, age range 21-59 years ( x ¯ = 39.07 years, SD = 11.46), with participants randomly allocated to conditions in a double-blind protocol. Participants also completed a 14-day food diary to gather information on micronutrient intake. The cognitive test battery included measures from the Wechsler Adult Intelligence Scale-III (WAIS-III; Wechsler et al., 2008), Wechsler Memory Scale-IV (WMS-IV; Wechsler, 2009) and Delis-Kaplan Executive Function System (D-KEFS; Delis et al., 2001), along with the Doors and People (Baddeley et al., 1994) and a serial reaction time task. Analyses showed better performance on some tasks in all groups following the intervention period, notably on measures of verbal and visual memory and visuomotor processing speed. The Multivitamin group showed significant improvements on tasks of visual strategy generation (along with the Vitamin C group), motor planning, explicit and implicit learning, and working memory. This evidence suggests that sub-optimal micronutrient intake may have a negative effect on cognition across the lifespan.

Birth seasonality and risk of autism spectrum disorder

Season of birth has been hypothesized to be a risk factor for autism spectrum disorder (ASD). However, the evidence has been mixed and limited due to methodological challenges. We examine ASD birth trends for 5,464,628 births across 5 countries. ASD birth prevalence data were obtained from the International Collaboration for Autism Registry Epidemiology database, including children born in Denmark, Finland, Norway, Sweden, and Western Australia. Empirical mode decomposition and cosinor modeling were used to assess seasonality. We show seasonal variation in ASD births for the countries of Finland and Sweden. There was a modest increase in risk for children born in the fall and a modest decrease in risk for children born in the spring. Solar radiation levels around conception and the postnatal period were inversely correlated with seasonal trends in ASD risk. In the first multinational study of birth seasonality of ASD, there was evidence supporting the presence of seasonal trends in Finland and Sweden. The observations that risk was highest for fall births (i.e., conceived in the winter) and lowest for spring births (i.e., conceived in the summer), and sunlight levels during critical neurodevelopmental periods explained much of the seasonal trends, are consistent with the hypothesis that a seasonally fluctuating risk factor may influence risk of ASD.

Vitamin D attenuates cerebral artery remodeling through VDR/AMPK/eNOS dimer phosphorylation pathway after subarachnoid hemorrhage in rats

The role of vitamin D3 (VitD3) in the upregulation of osteopontin (OPN) and eNOS in the endothelium of cerebral arteries after subarachnoid hemorrhage (SAH) is investigated. The endovascular perforation SAH model in Sprague-Dawley rats ( n = 103) was used. The VitD3 pretreatment (30 ng/kg) increased endogenous OPN and eNOS expression in cerebral arteries compared with naïve rats ( n = 5 per group). Neurobehavioral scores were significantly improved in Pre-SAH+VitD3 group compared with the SAH group. The effects of VitD3 were attenuated by intracerebroventricular (i.c.v) injections of siRNA for the vitamin D receptor (VDR) and OPN in Pre-SAH+VitD3+VDR siRNA and Pre-SAH+VitD3+OPN siRNA rats, respectively ( n = 5 per group). The significant increase of VDR, OPN and decrease of C44 splicing in the cerebral arteries of Pre-SAH+VitD3 rats lead to an increase in basilar artery lumen. The increase in VDR expression led to an upregulation and phosphorylation of AMPK and eNOS, especially dimer form, in endothelium of cerebral artery. The results provide that VitD3 pretreatment attenuates cerebral artery remodeling and vasospasm through the upregulation of OPN and phosphorylation of AMPK (p-AMPK) and eNOS (p-eNOS) at Ser1177-Dimer in the cerebral arteries. Vitamin D may be a useful new preventive and therapeutic strategy against cerebral artery remodeling in stroke patients.

Steroidal pheromones and their potential target sites in the vomeronasal organ

Steroids are important olfactory signals in most mammalian species. The vomeronasal organ has been suspected to be the primary target of pheromones. In rat vomeronasal sensory neurons express steroid binding proteins and nuclear receptors. Some binding globulins were found also in single ciliated cells of the non-sensory vomeronasal epithelium. Immunoelectron microscopy revealed VDR in olfactory microvilli and DPB in apical membrane protrusions of supporting sells within the sensory epithelium. Pilot behavioral studies with dogs showed increased sniffing duration upon exposure to low concentrations of vitamin D while higher concentrations were less effective. It has been shown that vitamin D has pheromone-like properties in lizards. Our histochemical and behavioral observations indicate that the mammalian vomeronasal organ may be a vitamin D target. Olfactory functions of vitamin D involve most likely rapid membrane mediated effects rather than actions through nuclear receptors.

Trichotillomania Triggered by Vitamin D Deficiency and Resolving Dramatically With Vitamin D Therapy

Trichotillomania (TTM) is a disorder characterized by the individual pulling out his hair in a repetitive manner, resulting in significant hair loss, a feeling of tension before the hair pulling, and pleasure during it. Our understanding of the neurobiological basis of TTM is limited. However, the condition in all likelihood involves multiple pathways and a complex interaction between various genetic, psychological, and social factors. Vitamin D deficiency is thought to be linked to rickets in children and to a range of different diseases in adults, including osteoporosis, osteomalacia, cardiovascular diseases, cancer, dermatological diseases, and psychiatric disorders. We report a case of a 4-year-old girl with TTM triggered by vitamin D deficiency resolving dramatically with vitamin D therapy.

Do Alarmins Have a Potential Role in Autism Spectrum Disorders Pathogenesis and Progression?

Autism spectrum disorders (ASDs) represent a disabling condition in early childhood. A number of risk factors were proposed in order to explain their pathogenesis. A multifactorial model was proposed, and data supported the implication of genetic and environmental factors. One of the most accepted speculations is the existence of an imbalance of the immune system. Altered levels of cytokines, chemokines and immunoglobulins were demonstrated in patients with ASDs; in particular, proinflammatory mediators were significantly increased. Alarmins are a multifunctional heterogeneous group of proteins, structurally belonging to specific cells or incorporated by them. They are released in the surrounding tissues as a consequence of cell damage or inflammation. Their functions are multiple as they could activate innate immunity or recruit and activate antigen-presenting cells stimulating an adaptive response. Alarmins are interesting both for understanding the inflammatory process and for diagnostic purposes as biomarkers. Moreover, recent studies, separately, showed that alarmins like interleukin (IL)-33, high-mobility group box 1 (HMGB1), heat-shock protein (HSP) and S100 protein (S100) could play a relevant role in the pathogenesis of ASDs. According to the literature, some of these alarmins could be suitable as biomarkers of inflammation in ASD. Other alarmins, by interfering with the immune system blocking pro-inflammatory mediators, could be the key for ameliorating symptoms and behaviours in autistic disorders.

Vitamin D deficiency and depressive symptoms in the perinatal period

Depression affects 1 in 7 women during the perinatal period. Women with vitamin D deficiency may be at an increased risk for depression. This study investigated the relationship between maternal and cord blood 25-hydroxyvitamin D (25OHD) and maternal depressive symptoms over the perinatal period. Study objectives were to examine variations and relationships between maternal and cord blood vitamin D levels and maternal depressive symptoms over the perinatal period. At a large medical center in southern California, pregnant women (N = 126) were recruited for this longitudinal cohort study. Depressive symptoms (Edinburgh Postnatal Depression Screen, EPDS) and vitamin D status (25OHD) were measured at three time points in the perinatal period: time 1 (T1; N = 125) EPDS and 25OHD were collected in early pregnancy; time 2 (T2; N = 96) EPDS was conducted in the third trimester with blood collected at time of delivery; and time 3 (T3; N = 88) was collected postpartum. A significant inverse relationship between vitamin D status and depressive symptoms was observed between 25OHD and EPDS scores at all time points in this sample (T1 = - 0.18, P = 0.024; T2 = - 0.27, P = 0.009; T3 = - 0.22, P = 0.019). This association remained after controlling for confounders. Low cord blood 25OHD levels were inversely associated with higher EPDS scores in the third trimester (r = - 0.22, P = 0.02). Clinicians may want to consider screening women diagnosed with vitamin D deficiency for depression and vice versa. Vitamin D may represent an important biomarker for pregnant and postpartum women diagnosed with depression. Further studies examining underlying mechanisms and supplementation are needed.

Association of the Vitamin D Level and Quality of School Life in Adolescents with Irritable Bowel Syndrome

There is no treatment of choice for irritable bowel syndrome, which affects up to 20% of school-aged children. This cross-sectional study evaluated the difference in the average vitamin D level between subtypes of irritable bowel syndrome, and the relationship between the vitamin D level as well as the severity of irritable bowel syndrome symptoms. We included 124 adolescents aged 10–17 years (68 boys, 56 girls; mean age 12.29 ± 1.92 years) from 2014 to 2016. Patients with irritable bowel syndrome were diagnosed by Rome III criteria and classified by clinical manifestation: irritable bowel syndrome with constipation (n = 29), irritable bowel syndrome with diarrhea (n = 63), and irritable bowel syndrome with constipation and diarrhea (n = 32). The severity of irritable bowel syndrome symptoms and school absence were evaluated. Vitamin D levels were measured by serum 25-hydroxyvitamin D. The chi-square test and analysis of variance were used. The patients’ average vitamin D level was 16.25 ± 6.58 ng/mL. There was a significant negative association of the 25-hydroxyvitamin D level with symptom severity and school absence (p = 0.022 and p < 0.001, respectively). Vitamin D supplementation could be considered as a choice of therapeutic method.

The Levels of Vitamin D, Vitamin D Receptor, Homocysteine and Complex B Vitamin in Children with Autism Spectrum Disorders

Objective

Autism spectrum disorder (ASD) is a complex neurodevelopmental syndrome with an increasingly prevalent etiology, yet not fully understood. It has been thought that vitamin D, complex B vitamin levels and homocysteine are associated with environmental factors and are important in ASD. The aim of this study was to examine serum vitamin D, vitamin D receptor (VDR), homocysteine, vitamin B6, vitamin B12 and folate levels in ASD.

Methods

In this study, serum vitamin D and VDR, homocysteine, vitamins B6, B12 and folate levels were determined in 60 patients with ASD (aged 3 to 12 years) and in 45 age-gender matched healthy controls. In addition, calcium, phosphorus and alkaline phosphatase, which are associated with vitamin D metabolism, were measured from serum in both groups. ASD severity was evaluted by the Childhood Autism Rating Scale (CARS).

Results

Serum vitamin D and VDR were substantially reduced in patients with ASD in comparision to control group. However, homocysteine level was significantly higher and vitamin B6, vitamin B12 and folate were also reduced in patients with ASD. Total CARS score showed a positive association with homocysteine and a negative correlation with vitamins D,B6, B12, folate and VDR.

Conclusion

This comprehensive study, which examines many parameters has shown that low serum levels of vitamins D, B6, B12, folate and VDR as well as high homocysteine are important in the etiopathogenesis of ASD. However, further studies are required to define the precise mechanism(s) of these parameters and their contributions to the etiology and treatment of ASD.

Comparison of the effects of perceptual-motor exercises, vitamin D supplementation and the combination of these interventions on decreasing stereotypical behavior in children with autism disorder

OBJECTIVES

The aim of this study was to examine the combined effects of perceptual-motor exercises and vitamin D3 supplementation on the reduction of stereotypical behavior in children with autism spectrum disorder (ASD).

METHODS

In this study, 100 eligible children with age ranging from 6 to 9 years were randomly selected and divided into four groups: Group A-perceptual-motor exercises (n = 25); Group B-25-hydroxycholecalciferol (25 (OH) D) (n = 25); Group C-perceptual-motor exercises and 25 (OH) D (n = 25); and Group D-control (n = 25).

RESULTS

The stereotypes decreased from elementary level, 17% in Group A, 13% in Group B and 28% in Group C among the participants. There was no change in the stereotypical in the control group during the interventions. Also, the stereotypes in Group C showed the highest decrease, compared to the other three groups.

CONCLUSIONS

We concluded that combination of perceptual-motor exercises and vitamin D3 supplementation in children with ASD leads to significant reduction in their stereotypic behaviors.

Vitamin D3 deficiency in puberty rats causes presynaptic malfunctioning through alterations in exocytotic release and uptake of glutamate/GABA and expression of EAAC-1/GAT-3 transporters

Recent experimental and epidemiologic investigations have revealed that the central nervous system is a target for vitamin D3 action and also linked vitamin D3 deficiency to Alzheimer's and Parkinson's disease, autism and dementia. Abnormal homeostasis of glutamate and GABA and signaling disbalance are implicated in the pathogenesis of major neurological diseases. Here, key transport characteristics of glutamate and GABA were analysed in presynaptic nerve terminals (synaptosomes) isolated from the cortex of vitamin D3 deficient (VDD) rats. Puberty rats were kept at the VDD diet up to adulthood. VDD caused: (i) a decrease in the initial rates of L-[¹⁴C]glutamate and [³H]GABA uptake by plasma membrane transporters of nerve terminals; (ii) a decrease in exocytotic release of L-[¹⁴C]glutamate and [³H]GABA; (iii) changes in expression of glutamate (EAAC-1) and GABA (GAT-3) transporters. Whereas, the synaptosomal ambient levels and Ca²⁺-independent transporter-mediated release of L-[¹⁴C]glutamate and [³H]GABA were not significantly altered in VDD. Vitamin D3 is a potent neurosteroid and its nutritional deficiency can provoke development of neurological consequences changing glutamate/GABA transporter expressions and excitation/inhibition balance. Also, changes in glutamate transport can underlie lower resistance to hypoxia/ischemia, larger infarct volumes and worsened outcomes in ischemic stroke patients with VDD.

Fok-I, Bsm-I, and Taq-I Variants of Vitamin D Receptor Polymorphism in the Development of Autism Spectrum Disorder: A Literature Review

The role of vitamin D in the development of autism spectrum disorder (ASD) is of intensified interest in medical science in recent years. Vitamin D has a significant role in neurogenesis, neuroprotection, and neurodevelopment. Due to the close association of vitamin D with the brain, it has been found that in the pathophysiology of several neuropsychiatric disorders vitamin D receptor (VDR) polymorphism plays a significant role. In this review article, we looked for a relation between VDR polymorphism and ASD. We systemically reviewed all the potential articles on the relation between VDR polymorphism and ASD. We found that several VDR variants FokI, BsmI, and TaqI polymorphisms are related to ASD. Even paternal VDR polymorphism can be a causative factor for ASD in the offspring. The relation between FokI (ff) genotype polymorphism and increased level of serum 1,25(OH)D3 in ASD patients is a very significant finding. Variation of ASD-related genotypes in different ethnic population raises a big question on whether the environmental factors also can do changes in human genotypes leading to ASD.

Cholecalciferol counteracts depressive-like behavior and oxidative stress induced by repeated corticosterone treatment in mice

Depression is one of the most frequent neuropsychiatric diseases in the western world and its physiological causes are not yet fully understood. Since the available antidepressants failed to provide a complete illness remission, the diversification of the therapy in the management of depression could be a useful contribution. The present study aimed to investigate the cholecalciferol capability to revert depressive-like behavior induced by chronic corticosterone (CORT) treatment in mice and its implication on the oxidative stress modulation. Sixty minutes after having orally received different doses of cholecalciferol, adult male mice were evaluated in the forced swimming and tail suspension tests, whereas in the seven-day treatment they were only tested in tail suspension. Additionally, for 21 days, the animals received CORT (20 mg/kg, p.o.) and cholecalciferol or fluoxetine, once a day for the last 7-days of the CORT treatment. Moreover, the markers of oxidative stress, lipid peroxidation, protein carbonyl and nitrite levels were assessed in the plasma and brain's mice after the splash and tail suspension tests. It was observed that corticosterone treatment resulted in depressive-like behavior with established oxidative stress in mice, while cholecalciferol ameliorated both, behavioral (immobility time and grooming latency) and biochemical (protein carbonyl and nitrite levels) changes induced by CORT model, suggesting that cholecalciferol has antidepressant-like effect with the involvement of the oxidative stress modulation.

Single Nucleotide Polymorphisms in the Vitamin D Receptor Gene (VDR) May Have an Impact on Acute Pancreatitis (AP) Development: A Prospective Study in Populations of AP Patients and Alcohol-Abuse Controls

Vitamin D imbalance is suggested to be associated with the development of pancreatitis. Single nucleotide polymorphisms (SNPs), Apa-1, Bsm-1, Fok-1, and Taq-1, in the vitamin D receptor gene (VDR) are known in various diseases, but not yet in pancreatitis. The aim of this study was to explore possible associations of the four SNPs in the VDR receptor gene in a population of acute pancreatitis patients and alcohol-abuse controls, and to investigate the association with acute pancreatitis (AP) susceptibility. The study population (n = 239) included acute pancreatitis patients (n = 129) and an alcohol-abuse control group (n = 110). All patients met the Diagnostic and Statistical Manual of Mental Disorders (DSM IV) criteria for alcohol dependence. DNA was extracted from peripheral leukocytes and analyzed for VDR polymorphisms using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Odd ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression analysis. To date, we have found allele T in Taq-1 (OR = 2.61; 95% CI: 1.68⁻4.03; p < 0.0001) to be almost three times more frequent in the AP group compared to the alcohol-abuse control patients. Polymorphism Taq-1 occurring in the vitamin D receptor may have an impact on the development of acute pancreatitis due to the lack of the protective role of vitamin D.

Status of nutrients important in brain function in phenylketonuria: a systematic review and meta-analysis

Background

Despite early and ongoing dietary management with a phe-restricted diet, suboptimal neuropsychological function has been observed in PKU. The restrictive nature of the PKU diet may expose patients to sub-optimal nutritional intake and deficiencies which may impact normal brain function. A systematic review of the published literature was carried out, where possible with meta-analysis, to compare the status of nutrients (Nutrients: DHA, EPA phospholipids, selenium, vitamins B₆, B₁₂, E, C, A, D, folic acid, choline, uridine, calcium, magnesium, zinc, iron, iodine and cholesterol) known to be important for brain development and functioning between individuals with PKU and healthy controls.

Results

Of 1534 publications identified, 65 studies met the entry criteria. Significantly lower levels of DHA, EPA and cholesterol were found for PKU patients compared to healthy controls. No significant differences in zinc, vitamins B₁₂, E and D, calcium, iron and magnesium were found between PKU patients and controls. Because of considerable heterogeneity, the meta-analyses findings for folate and selenium were not reported. Due to an insufficient number of publications (< 4) no meta-analysis was undertaken for vitamins A, C and B₆, choline, uridine, iodine and phospholipids.

Conclusions

The current data show that PKU patients have lower availability of DHA, EPA and cholesterol. Compliance with the phe-restricted diet including the micronutrient fortified protein substitute (PS) is essential to ensure adequate micronutrient status. Given the complexity of the diet, patients’ micronutrient and fatty acid status should be continuously monitored, with a particular focus on patients who are non-compliant or poorly compliant with their PS. Given their key role in brain function, assessment of the status of nutrients where limited data was found (e.g. choline, iodine) should be undertaken. Standardised reporting of studies in PKU would strengthen the output of meta-analysis and so better inform best practice for this rare condition.

Electronic supplementary material

The online version of this article (10.1186/s13023-018-0839-x) contains supplementary material, which is available to authorized users.

Postnatal Vitamin D Intake Modulates Hippocampal Learning and Memory in Adult Mice

Vitamin D (VD) is a neuroactive steroid crucial for brain development, function and homeostasis. Its deficiency is associated with numerous brain conditions. As such, VD and its variants are routinely taken by a broad of groups with/without known VD deficiency. In contrast, the harmful effects of VD overdose have been poorly studied. Similarly, the developmental stage-specific VD deficiency and overdose have been rarely explored. In the present work, we showed that postnatal VD supplementation enhanced the motor function transiently in the young adult, but not in the older one. Postnatal VD intake abnormality did not impact the anxiety and depressive behavior but was detrimental to spatial learning and hippocampus-dependent memory. At the molecular level we failed to observe an obvious and constant change with the neural development and activity-related genes examined. However, disrupted developmental expression dynamics were observed for most of the genes, suggesting that the altered neural development dynamics and therefore aberrant adult plasticity might underlie the functional deficits. Our work highlights the essence of VD homeostasis in neural development and adult brain function. Further studies are needed to determine the short- and long-term effects VD intake status may have on brain development, homeostasis, and diseases.

Antitumoral effects of the alkynylphosphonate analogue of calcitriol EM1 on glioblastoma multiforme cells

Glioblastoma multiforme (GBM) is the worst and most common brain tumor, characterized by high proliferation and invasion rates. The current standard treatment is mainly based on chemoradiotherapy and this approach has slightly improved patient survival. Thus, novel strategies aimed at prolonging the survival and ensuring a better quality of life are necessary. In the present work, we investigated the antitumoral effect of the novel analogue of calcitriol EM1 on GBM cells employing in vitro, in silico, and in vivo assays. In vitro, we demonstrated that EM1 treatment selectively decreases the viability of murine and human tumor cells without affecting that of normal human astrocytes. The analysis of the mechanisms showed that EM1 produces cell cycle arrest in the T98G cell line, which is accompanied by an increase in p21, p27, p57 protein levels and a decrease in cyclin D1, p-Akt-S473, p-ERK1/2 and c-Jun expression. Moreover, EM1 treatment also exerts in GBM cells anti-migratory effects and decreases their invasive capacity by a reduction in MMP-9 proteolytic activity. In silico, we demonstrated that EM1 is able to bind to the vitamin D receptor with greater affinity than calcitriol. Finally, we showed that EM1 treatment of nude mice administered at 50ug/kg body weight during 21days neither induces hypercalcemia nor toxicity effects. In conclusion, all the results indicate the potential of EM1 analogue as a promising therapeutic alternative for GBM treatment.

Serum vitamin D in patients with mild cognitive impairment and Alzheimer's disease

OBJECTIVES

To determine the relevance of Mini-Mental State Examination (MMSE), serum 25-hydroxyvitamin D (25(OH)D3), and 1,25(OH)2D3 concentrations to mild cognitive impairment (MCI) and various stages of Alzheimer's disease (AD).

MATERIALS AND METHODS

The study included 230 participants (>74 years) allocated to three main groups: 1-healthy subjects (HS, n = 61), 2-patients with MCI (n = 61), and 3- patients with Alzheimer's disease (AD) subdivided into three stages: mild (n = 41), moderate (n = 35), and severe AD (n = 32). The cognitive status was evaluated using MMSE. Serum 25 (OH)D3 (ng/ml) and 1,25(OH)2D3 concentrations (pg/ml) were determined by competitive radioimmunoassay.

RESULTS

MMSE scores and 25(OH)D3 were decreased in MCI and all stages of the AD in both genders. MMSE variability was due to gender in HS (11%) and to 25(OH)D3 in MCI (15%) and AD (26%). ROC analysis revealed an outstanding property of MMSE in diagnosis of MCI (AUC, 0.906; CI 95%, 0.847-0.965; sensitivity 82%; specificity, 98%) and AD (AUC, 0.997; CI 95%, 0.992-1; sensitivity, 100%; specificity, 98%). 25(OH)D3 exhibited good property in MCI (AUC, 0.765; CI 95%, 0.681-0.849; sensitivity, 90%; specificity, 54%) and an excellent property in diagnosis of AD (AUC, 0.843; CI 95%, 0.782-0.904; sensitivity, 97%; specificity, 79%). Logistic analyses revealed that, in MCI, MMSE could predict (or classify correctly) with 97.6% accuracy (Wald, 15.22, β, -0.162; SE, 0.554; OR = 0.115:0.039-0.341; p = .0001), whereas 25(OH)D3 with 80% accuracy (Wald, 41,013; β, -0.213; SE, 0.033; OR = 0.808: 0.757-863; p = .0001). 25(OH)D3 was the only significant predictor for the severe AD and contributed to MMSE variability. Age and gender were significant predictors only in the moderate AD. In patients with MCI, 25(OH)D3 and 1,25(OH)2D3 were correlated men, but in case of the AD, they were correlated in women.

CONCLUSIONS

MMSE and serum 25(OH)D3 concentrations could be useful biomarkers for prediction and diagnosis of MCI and various stages of the AD. The results support the utility of vitamin D supplementation in AD therapy regimen.

Lead Affects Vitamin D Metabolism in Rats

A negative association between blood lead and vitamin D concentrations has been reported, however, experimental data on the effect of lead (Pb) on vitamin D metabolism is scarce. We investigated the effects of Pb on serum vitamin D metabolites, vitamin D activating enzymes and vitamin D receptor (VDR) in rats. Newborn Wistar rat pups were exposed to 0.2% Pb-acetate via their dams’ drinking water from post-natal day (PND) 1 to 21 and directly in drinking water until PND30. Serum 25-hydroxyvitamin D was analyzed with LC-MS/MS and 1,25-dihydroxyvitamin D with an immunoassay. Tissue expression of vitamin D activating enzymes and VDR were measured by Western blot and immunohistochemistry. Serum 25-hydroxyvitamin D was significantly decreased at both PND21 and PND30, whereas 1,25-dihydroxyvitamin D was decreased (p < 0.05) only at PND21 in the Pb-exposed rats. Expression of renal 1-α-hydroxylase was decreased by Pb only at PND21 (p < 0.05) but the brain 1-α-hydroxylase was not affected. Hepatic 25-hydroxylase expression was significantly decreased at PND21 but significantly increased at PND30 by Pb exposure. VDR expression in the brain was increased at both PND21 and PND30 (p < 0.05). These results suggest that Pb interferes with vitamin D metabolism by affecting the expression of its metabolizing enzymes.

Vitamin D supplementation attenuates the behavioral scores of neuropathic pain in rats

Objective(s): Neuropathic pain due to lesion or dysfunction of the peripheral or central nervous system is often refractory to the conventional analgesics. Currently, there is no proven treatment to prevent or cure neuropathic pain. A recent surge of new data suggests the potential effects of vitamin D in the medical community. This study was designed to determine whether acute or chronic vitamin D administration was effective in alleviating symptoms of neuropathic pain in a rat model of neuropathic pain. Materials and Methods: Neuropathic pain was induced by chronic constriction injury (CCI) of the sciatic nerve in the rats that resulted in thermal hyperalgesia, mechanical, and cold allodynia. Results: Acute vitamin D injections (250, 500, and 1000 unit/kg i.p.) on the 7th, 14th, and 21st postoperative days could not attenuate mechanical and cold allodynia as well as heat hyperalgesia compared to CCI group. But when vitamin D (1000 unit/kg i.p.) administration was started on the first day after surgery and given daily until the 21st day, cold allodynia and heat hyperalgesia considerably were attenuated. However, no differences in paw withdrawal thresholds were observed. Conclusion: These results indicate that chronic vitamin D administrations can attenuate the behavioral scores of neuropathic pain in rats.

The effects of different combinations of perceptual-motor exercises, music, and vitamin D supplementation on the nerve growth factor in children with high-functioning autism

The present study investigated the effects of different combinations of perceptual-motor exercises, music, and Vitamin D consumption on the nerve growth factor (NGF) in children with high-functioning autism. 48 children with autism, aged between six and nine years, were divided into four groups: Group A- perceptual-motor activities along with music (n = 12); Group B-Vitamin D supplementation (n = 12); Group C-perceptual-motor activities along with music and Vitamin D (n = 12); and Group D-control (n = 12). Participants' blood NGF level was measured before and after the intervention. The results showed a significant improvement in the NGF levels in Groups B and C due to the interventions. Also, in Group A, the NGF levels increased compared to Group D, although this increase was not significant. In addition, the intake of Vitamin D along with perceptual-motor exercises resulted in a significant increase in the levels of NGF compared to Groups A, B and D. These findings suggest that perceptual-motor exercises along with music as well as taking Vitamin D may provide two appropriate interventions for improving NGF in children with autism.

25-Hydroxvitamin D concentrations are not lower in children with bronchial asthma, atopic dermatitis, obesity, or attention-deficient/hyperactivity disorder than in healthy children

Vitamin D (vitD) is involved in immune regulation, and its receptor has been identified in several tissues including lung, adipose tissue, brain, and skin. Based on these observations, it has been suggested that vitD has an essential role not only in bone metabolism but also in other diseases such as atopic dermatitis (AD), bronchial asthma (BA), attention-deficit/hyperactivity disorder (ADHD), and obesity because the affected tissues express vitD receptors. Furthermore, obesity, AD, and BA are regarded as inflammatory diseases. Therefore, we hypothesized that vitD concentrations are lower in children with AD, BA, ADHD, and obesity compared to healthy children. We measured 25-hydroxyvitamin D concentrations in 235 children (60% boys, age 9.3±1.7years) with obesity, BA, AD, or ADHD and compared them to those of 3352 children from a healthy population. Additionally, parathyroid hormone was measured in the children with obesity, ADHD, BA, and AD. VitD concentrations were not lower in children with obesity, ADHD, BA, and AD compared to healthy children. In multiple regression analyses adjusted to migration background, time period of blood sample, age, and sex, VitD levels correlated significantly with the severity of AD measured by SCORing Atopic Dermatitis index and attention deficit measured by Conners questionnaire in ADHD. VitD levels were not linked to hyperactivity in ADHD, the severity of BA measured as forced expiration volume in the first second, or body mass index standard deviation score. Parathyroid hormone was not associated with the activity of any analyzed disease. In conclusion, most of our findings do not support the hypothesis that vitD is involved in the pathogenesis of these entities.

Polymorphisms in Vitamin D Receptor Genes in Association with Childhood Autism Spectrum Disorder

Both genetic and environmental factors have been implicated in the etiology of autism spectrum disorder (ASD). This case-control study aimed to determine the association of single-nucleotide polymorphisms (SNPs) rs731276 (TaqI), rs1568820 (Cdx2), rs1544410 (BsmI), and rs2228570 (FokI) in the vitamin D receptor (VDR) gene with susceptibility of childhood ASD and severity of the disease. A total of 201 children with ASD and 200 healthy controls from the Han Chinese population were recruited. SNP genotyping was carried out by TaqMan probe-based real-time PCR using genomic DNA extracted from blood cells. Among four examined SNPs, only the CT genotype (odds ratio (OR) = 1.96, 95% confidence interval (CI) = 1.05-3.68, P = 0.0351) and the C allele (OR = 1.88, 95% CI = 1.02-3.46, P = 0.0416) of the rs731276 were significantly associated with increased risks of childhood ASD. None of the SNPs were associated with severity of childhood ASD. Our results reveal that certain polymorphisms in the VDR gene are a risk factor related to childhood ASD in the Han Chinese population.

Epilepsy and vitamin D: a comprehensive review of current knowledge

Vitamin D has been considered as neurosteroid, and its pivotal role in neuroprotection, brain development, and immunomodulation has been noticed in studies; however, our knowledge regarding its role in neurological disorders is still developing. The potential role of vitamin D in the pathophysiology and treatment of epilepsy, as one the most prevalent neurological disorders, has received less attention in recent years. In this article, we review the possible relationship between vitamin D and epilepsy from different aspects, including the action mechanism of vitamin D in the central nervous system and ecological and epidemiological findings. We also present the outcome of studies that evaluated the level of vitamin D and the impact of administrating vitamin D in epileptic patients or animal subjects. We also review the current evidence on interactions between vitamin D and antiepileptic drugs.