Epilepsy and vitamin D

Analysis of Plasma-Derived Exosomal MicroRNAs as Potential Biomarkers for Canine Idiopathic Epilepsy

Epilepsy is one of the most prevalent complex neurological diseases in both the canine and human species, with the idiopathic form as its most common diagnosis. MicroRNAs (miRNAs) are small, noncoding RNA molecules that play a role in gene regulation processes and appear to be a promising biological target for convulsion control. These molecules have been reported as constituents of the internal content of exosomes, which are small extracellular vesicles released by cells. In this study, exosome samples were isolated from the plasma of 23 dogs, including 9 dogs with epilepsy responsive to treatment, 6 dogs with drug-resistant epilepsy, and 8 control dogs. Plasma exosomes were then characterized by electron transmission microscopy, nanoparticle tracking analysis, and dot blotting. Afterwards, the microRNA-enriched RNA content of exosomes was isolated, and miRNA quantification was performed by quantitative real-time PCR. Seven circulating miRNAs that have been previously described in the literature as potential diagnostic or prognostic biomarkers for epilepsy were evaluated. We observed significant differences in miR-16 (p < 0.001), miR-93-5p (p < 0.001), miR-142 (p < 0.001), miR-574 (p < 0.01), and miR-27 (p < 0.05) levels in dogs with refractory epilepsy compared to the control group. In drug-sensitive epileptic dogs, miR-142 (p < 0.01) showed significant differences compared to healthy dogs. Moreover, distinct levels of miR-16 (p < 0.05), miR-93-5p (p < 0.01), miR-132 (p < 0.05), and miR-574 (p < 0.05) were also found between drug-sensitive and drug-resistant epileptic dogs. Our results present plasma-circulating exosomes as an advantageous source of epileptic biomarkers, highlighting the potential of miRNAs as prognostic and diagnostic biomarkers of canine idiopathic epilepsy.

Interaction between vitamin D level, antiseizure medications (ASM) and seizure control in epilepsy adult patients

OBJECTIVE

To investigate vitamin D levels and factors associated with seizure control in adult patients with epilepsy (APE).

METHOD

Cross-sectional study with APE in routine outpatient follow-up at a neurology clinic. Clinical variables, antiseizure medications (ASM) and vitamin D were investigated. Data were analyzed using the Chi2 or Fisher's exact tests, Mann-Whitney, Spearman's correlation coefficient, ROC curve and univariate and multiple logistic regression analysis.

RESULTS

Mean age was 46.5±15.1 years and disease duration was 27.5±17.0 years; 52.7% (n=49) of patients used one ASM and 47.3% (n=44) used≥2 ASM. There was a significant difference in the level of vitamin D according to the number of ASM and it was higher in patients who used a single ASM (26.02±10.22 versus 22.50±8.69; P=0.048). In the logistic regression, when vitamin D level was set at 20ng/mL, the chance of seizure control for patients using a single ASM was 6.99 times greater than for those using≥2 ASM. When vitamin D level was set at 40ng/mL, the number of ASM did not modify seizure control. There was no correlation between vitamin D and disease duration, patient age and age at the time of the first seizure. In the logistic regression, it was observed that satisfactory levels of vitamin D did not modify potential seizure control.

CONCLUSION

Thirty-three percent (33%) of patients presented with vitamin D deficiency (values below 20ng/mL) and 80% had vitamin D levels below what is recommended (30ng/mL). The use of ASM, when associated with different levels of vitamin D, modified the probability of seizure control in APE. Vitamin D levels and intrinsic epilepsy factors are associated with failure to effectively control seizures.

Investigation of the Effect of Antiepileptics on Vitamin D and Calcium Levels

Purpose: The purpose of our study is to investigate Vitamin D and calcium levels in epilepsy patients using different antiepileptic agents and to investigate the relationship between vitamin D levels and various factors such as the type of antiepileptic agent, patient age and gender. Methodology: This retrospective case-control study enrolled a total of 290 participants, including 141 epilepsy patients followed up in AlanyaAlaaddinKeykubat University neurology outpatient clinic and 150 healthy individuals who applied to the neurology outpatient clinic for different reasons from January 2018 to January 2021. Demographics, detailed history, use of medications, duration of antiepileptic use, plasma 25-hydroxy Vitamin D and calcium levels of all participants were recorded. Results: The average Vitamin D level was 15.46 in the epilepsy group and 16.95 in the control group. Vitamin D level did not differ significantly by group (p>0.05). No significant relationship was found between age and vitamin D levels in both groups, and Vitamin D levels were statistically significantly lower in women in the epilepsy group. Vitamin D level was below 20 in 69.6% of healthy control group, 78.9% of carbamazepine users, 62.5% of lacosamide users, all lamotrigine users, 66.7% of levatiracetam users, and 72.4% of sodium valproate users. There was no significant relationship between Vitamin D level and the drug used (p>0.05).There was a significant relationship only between calcium level and carbamazepine (p

Association between serum vitamin D levels and age in patients with epilepsy: a retrospective study from an epilepsy center in Saudi Arabia

BACKGROUND

Vitamin D deficiency has been linked to various medical conditions such as bone loss, decreased mineralization, endocrine disorders, and central nervous system disorders, including epilepsy. Vitamin D deficiency is prevalent among patients with epilepsy (PWE). However, the specific association between vitamin D levels and age in PWE is unclear.

OBJECTIVES

Identify the relation between vitamin D level and age in PWE and evaluate factors that may play a role in seizure control.

DESIGN

Retrospective analytical medical record review SETTING: Outpatient epilepsy research clinic in Saudi Arabia PATIENTS AND METHODS: Between November 2016 and April 2020, we selected eligible PWE aged older than 14 years whose vita-min D levels were recorded at least once after reviewing 1550 patient electronic files. We analyzed data on serum vitamin D level by age and other factors, vitamin D supplement use, seizure classification, and conducted a multivariate logistic regression to assess associations with seizure control.

MAIN OUTCOME MEASURES

Relationships between vitamin D levels and age and factors that might affect seizure control.

SAMPLE SIZE

524 patients RESULTS: The prevalence of low serum vitamin D levels was high (86.8%). The median vitamin D level in all patients was low (38 nmol/L), and was lower in young PWE than in adult PWE (P<.01). Only 146 patients received vitamin D supplements. High vitamin D levels were associated with a 40% seizure reduction.

CONCLUSION

Vitamin D deficiency is underestimated in PWE in Saudi Arabia, and is more prevalent among young adults and patients on polytherapy than in other PWE. Patients with high vitamin D levels had good seizure control compared with those with low levels. The effect of vitamin D supplements on seizure control should be further investigated in randomized control trials.

LIMITATIONS

Retrospective study and no categorization by presence of supplementation.

CONFLICT OF INTEREST

None.

The effects of vitamin D3 and melatonin combination on pentylenetetrazole-induced seizures in mice

BACKGROUND

Epileptic seizures are associated with the overproduction of free radicals in the brain leading to neuronal cell death. Therefore, reduction of oxidative stress may inhibit seizure-induced neuronal cell damage. Current study evaluated the effects of Vit D3 and melatonin and their combination on pentylenetetrazol (PTZ)-induced tonic clonic seizures in mice.

METHODS

Animals were divided into six groups. Group I was administrated with normal saline (0.5 ml, intraperitoneally (i.p.)) on the 15th day of experiment. Group II was injected with PTZ (60 mg/kg dissolved in 0.5 ml normal saline, i.p) on the 15th day. Groups III-IV were treated with diazepam (4 mg/kg/day), Vit D3 (6000 IU/kg/day), melatonin (20 mg/kg/day) and Vit D3 (6000 IU/kg/day)/melatonin (20 mg/kg/day), respectively, and were then injected with PTZ (60 mg/kg) on the 15th day of experiment. Immediately after the injection of PTZ on the 15th day, mice were observed for a 30-min period for the measurement of seizure latency and duration. For determination of oxidative stress markers, malondialdehyde (MDA) level and superoxide dismutase (SOD) activity were measured in mouse brains.

RESULTS

Treatment with Vit D3, melatonin, and Vit D3/melatonin significantly increased seizure latency and decreased seizure duration. The brain level of MDA was lower and SOD activity was greater than the PTZ group. Mice treated with Vit D3/melatonin had lower seizure duration compared to other treated groups.

CONCLUSIONS

Combination of Vit D3 and melatonin may reduce seizure frequency in epileptic patients; this effect may result from various mechanisms including inhibition of oxidative stress.

Vitamin D Supplementation Rescues Aberrant NF-κB Pathway Activation and Partially Ameliorates Rett Syndrome Phenotypes in Mecp2 Mutant Mice

Rett syndrome (RTT) is a severe, progressive X-linked neurodevelopmental disorder caused by mutations in the transcriptional regulator MECP2. We previously identified aberrant NF-κB pathway upregulation in brains of Mecp2-null mice and demonstrated that genetically attenuating NF-κB rescues some characteristic neuronal RTT phenotypes. These results raised the intriguing question of whether NF-κB pathway inhibitors might provide a therapeutic avenue in RTT. Here, we investigate whether the known NF-κB pathway inhibitor vitamin D ameliorates neuronal phenotypes in Mecp2-mutant mice. Vitamin D deficiency is prevalent among RTT patients, and we find that Mecp2-null mice similarly have significantly reduced 25(OH)D serum levels compared with wild-type littermates. We identify that vitamin D rescues aberrant NF-κB pathway activation and reduced neurite outgrowth of Mecp2 knock-down cortical neurons in vitro. Further, dietary supplementation with vitamin D in early symptomatic male Mecp2 hemizygous null and female Mecp2 heterozygous mice ameliorates reduced neocortical dendritic morphology and soma size phenotypes and modestly improves reduced lifespan of Mecp2-nulls. These results elucidate fundamental neurobiology of RTT and provide foundation that NF-κB pathway inhibition might be a therapeutic target for RTT.

Vitamin D status in an Australian patient population: a large retrospective case series focusing on factors associated with variations in serum 25(OH)D

OBJECTIVES

To investigate whether sex, age, medical specialty and seasonal variations in serum concentration of 25-hydroxy vitamin D (25(OH)D) are evident among an Australian patient population.

DESIGN

Retrospective study analysing the results of serum 25(OH)D lab tests and vitamin D supplementation from Royal Melbourne Hospital (RMH) between 2014 and 2017.

SETTING

Tertiary healthcare centre in Victoria, Australia.

PARTICIPANTS

30 023 patients (inpatient and outpatient) who had their serum 25(OH)D levels measured at RMH between 2014 and 2017.

MAIN OUTCOME MEASURES

Serum 25(OH)D levels stratified according to patients' sex, age and medical specialty admitted to, as well as the season and year (2014 to 2017) 25(OH)D level was measured.

RESULTS

Mean serum 25(OH)D level of study population was 69.9 nmol/L (95% CI 69.5 to 70.2). Only 40.2% patients in this cohort were sufficient in vitamin D (>75 nmol/L). On average, 25(OH)D levels in male patients were 6.1 units (95% CI 5.4 to 6.9) lower than in females. Linear regression analysis found that 25(OH)D levels increased by 0.16 unit (95% CI 0.14 to 0.18) for every year increase in age. One-way analysis of variance showed patients from neurology had the highest average 25(OH)D level, 76.8 nmol/L (95% CI 74.2 to 79.3) compared with other medical specialties. Mean 25(OH)D level during winter, 64.9 nmol/L (95% CI 64.2 to 65.6) was significantly lower compared with other seasons despite supplementation. Average 25(OH)D level measured in 2014, 71.5 nmol/L (95 CI% 70.8 to 72.2) was significantly higher than levels measured in 2016-2017.

CONCLUSIONS

There is a sex, age, medical specialty, seasonal and yearly variation in vitamin D status in an Australian patient population. The association between low vitamin D status and winter despite supplementation suggests other interventions are required to boost serum 25(OH)D levels.

Paradoxical deterioration in seizure control due to anticonvulsant-induced hypocalcaemia

Hepatic cytochrome P450 enzyme induction is associated with certain antiepileptic drugs (AEDs) and may result in hypocalcaemia secondary to vitamin D deficiency. We report a case of a 44-year-old man with a history of epilepsy, who presented with breakthrough seizures after having previously been seizure-free for 11 years. Investigations revealed severe hypocalcaemia with a corrected calcium of 1.7 mmol/L. His phenytoin dose was increased, and he was started on calcium supplementation. He was discharged with a corrected calcium level of 2.05 mmol/L but was readmitted 1 week later with further seizures and a corrected calcium of 1.89 mmol/L. 25-hydroxyvitamin D was low. AED-induced hypocalcaemia was suspected, which had been made paradoxically worse by the increase in phenytoin dose. Alfacalcidol was prescribed and he was switched from phenytoin to levetiracetam with resolution of hypocalcaemia and no further seizures. The authors recommend screening for calcium and vitamin D deficiency in patients on enzyme-inducing AEDs.

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.

Vitamin D, bone mineral density and risk of fracture in people with intellectual disabilities

BACKGROUND

People with intellectual disabilities (IDs) have very high rates of osteoporosis and fractures, to which their widespread vitamin D deficiency and other factors could contribute. We aimed to assess in people with IDs previously treated for vitamin D deficiency (1) long-term adherence to vitamin D supplementation and (2) bone mineral density (BMD), as an indicator for risk of fractures, according to vitamin D supplementation and other factors.

METHOD

We recorded height, weight, medical, pharmacological, dietary and lifestyle assessment. Blood sample were taken for vitamin D and related analytes. dual-energy X-ray absorptiometry for BMD was performed.

RESULTS

Of 51 study participants (mean [standard deviation, SD] age 51.5 [13.6] years, 57% male), 41 (80.4%) were taking vitamin D and 10 were not. Mean [SD] serum vitamin D was 81.3 [21.3] vs. 25.2 [10.2] nmol/L (P < 0.0001), respectively. Thirty-six participants underwent a dual-energy X-ray absorptiometry scan, which showed osteoporosis in 23.7% and osteopenia in 52.6%. Participants on vitamin D had higher BMD than those who were not, a statistically significant difference when confounders (lack of mobility and hypogonadism) were removed. BMD was significantly different according to mobility, particularly in wheelchair users, in whom hip BMD was 33% lower (P < 0.0001) than in participants with normal mobility. Participants still taking vitamin D showed a 6.1% increase in BMD at the spine (P = 0.003) after mean [SD] 7.4 [1.5] years vitamin D treatment.

CONCLUSIONS

In people with IDs and previous vitamin D deficiency, BMD increases on long-term vitamin D supplementation. However, additional strategies must be considered for osteoporosis and fracture prevention in this population.

Vitamin D supplementation to prevent vitamin D deficiency for children with epilepsy: Randomized pragmatic trial protocol

BACKGROUND

Vitamin D deficiency is highly prevalent among children with epilepsy. Lack of high-quality evidence led to variability among scientific societies recommendations. Therefore, we aim to determine the efficacy of different common doses used in the pediatric practice to maintain optimal 25-hydroxy vitamin D (25 [OH] vitamin D) level in children with epilepsy and normal baseline 25 (OH) vitamin D level over 6 months of supplementation.

METHODS

This is a protocol for phase IV pragmatic randomized superiority controlled open-label trial at King Saud University Medical City in Riyadh. Children with epilepsy and receiving chronic antiepliptic medication and normal baseline 25 (OH) vitamin D level will be randomly assigned to receive Cholecalciferol 400 IU/day versus 1000 IU/day for 6 months. Our primary outcome is the proportion of children with vitamin D insufficiency (25 (OH) vitamin D level < 75nmol/L) at 6 months. Secondary outcomes include seizure treatment failure, seizure frequency, parathyroid hormone (PTH) levels, bone mineral density, and safety.

DISCUSSION

Our trial is set out to evaluate the efficacy of common different vitamin D maintenance doses on 25 (OH) vitamin D level, seizure control, and bone health for children with epilepsy. The results of our study will possibly help in shaping current vitamin D guidelines for vitamin D supplementation in children with epilepsy and provide a link between 25 (OH) vitamin D level and seizure control.

The Association Between Vitamin D Binding Protein Polymorphisms and Vitamin D Level on Epilepsy in China

Accumulating studies suggest the potential association between epilepsy and vitamin D (VD) in recent years. Vitamin D binding protein (VDBP) is the main VD carrier and can affect the availability of VD and its metabolites. Thus, this study aimed to investigate the association between VDBP polymorphisms and VD level on epilepsy. A total of 220 epilepsy patients and 210 health controls were enrolled and polymorphisms of VDBP (rs4588, rs7041, rs2298849, and rs2282679) genotype were detected using the PCR-ligase detection reaction method. The circulating status of VD metabolites, 25(OH)D and 24,25(OH)₂D, was detected by a validated high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method, and the VD metabolite ratio (VMR), 24,25(OH)₂D:25(OH)D, was then calculated. The frequency of rs4588(C>A) and rs2282679(A>C) genotype with AC was significantly lower among the patients relative to the controls [odds ratio, OR = 0.597, 95% confidence interval, CI = 0.401-0.890, p = 0.011 for rs4588(C>A); OR = 0.611, 95% CI = 0.409-0.912, p = 0.016 for rs2282679(A>C), respectively]. For rs7041 genotype distribution, VMR level was significantly higher in patients with GG genotype than in those carrying TT and TG genotype (p = 0.008). Our study demonstrated that the polymorphisms of VDBP rs4588 and rs2282679 may play a potentially important role in epilepsy susceptibility in Chinese Han population.

Short-Term Vitamin D3 Supplementation in Children with Neurodisabilities: Comparison of Two Delivery Methods

BACKGROUND/AIMS

Vitamin D deficiency is common in children with neurodisabilities. Oral vitamin D3 may not be absorbed appropriately due to dysphagia and tube feeding. The aim of this study was to compare efficacy of vitamin D3 buccal spray with that of oral drops.

METHODS

Twenty-four children with neurodisabilities (5-17 years) and vitamin D deficiency (25(OH)D ≤20 ng/mL) were randomized to receive vitamin D3 buccal spray 800 IU/daily (n = 12) or oral drops 750 IU/daily (n = 12) for 3 months during winter.

RESULTS

Both groups had a significant increase in 25(OH)D (z = 150; p < 0.0001). The differences between baseline and final parathyroid hormone measurements did not reach significance in both groups. Markers of bone formation and resorption did not change significantly in both groups. The satisfaction with the formulation was significantly higher in the patients using spray.

CONCLUSION

Vitamin D3 supplementation with buccal spray and oral drops are equally effective in short-term treatment of vitamin D deficiency in children with neurodisabilities. Buccal spray may be more acceptable by the patients.

Expression Analysis of Vitamin D Signaling Pathway Genes in Epileptic Patients

Vitamin D deficiency has been detected in epileptic patients. Vitamin D participates in neuroprotection, brain cell proliferation, and differentiation. Consequently, vitamin D supplementation has been suggested as an alternative treatment in epileptic patients. We aimed at assessment of vitamin D signaling pathway in epileptic patients. In the present study, we evaluated vitamin D serum concentration as well as expression of vitamin D receptor (VDR) gene and genes encoding for vitamin D activating enzyme 1-alpha-hydroxylase (CYP27B1) and deactivating enzyme 24-hyroxylase (CYP24A1) in epileptic patients compared with healthy individuals. We found significant lower levels of vitamin D in epileptic patients compared with healthy subjects. Expression analyses showed significant downregulation of VDR expression in peripheral blood of epileptic patients compared with healthy subjects (relative expression (REx) = 0.16, P < 0.001). However, there was no significant difference in CYP24A1 expression between epileptic patients and normal subjects. CYP27B1 expression analysis showed significant upregulation in male patients aged between 30 and 40 (REx = 5.43, P = 0.013). After using two-way ANCOVA for adjusting the effects of sex and age, there was a statistically significant difference in the VDR expression values between patient and control groups (P < 0.001). Spearman's correlation analysis showed no significant correlation between genes expression levels and patients' age or vitamin D serum concentrations. However, we found significant correlations between VDR expression levels and CYP24A1/ CYP27B1 expression levels in epileptic patients (r = 0.435 and P < 0.001; r = 0.26 and P = 0.02 respectively). There was also a significant correlation between the expression levels of CYP24A1 and CYP27B1 (r = 0.349 and P = 0.001). Our study shows a possible role for VDR in the pathogenesis of epilepsy.

Vitamin D and autism, what's new?

An increasing amount of evidence points to the possibility that gestational and early childhood vitamin D deficiency [25(OH)D < 40 ng/ml] cause some cases of autism. Vitamin D is metabolized into a seco-steroid hormone that regulates about 3% of the 26,000 genes in the coding human genome. It is also a neurosteroid that is active in brain development, having effects on cellular proliferation, differentiation, calcium signaling, neurotrophic and neuroprotective actions; it also appears to have an effect on neurotransmission and synaptic plasticity. Children who are, or who are destined to become, autistic have lower 25(OH)D levels at 3 months of gestation, at birth and at age 8 compared to their unaffected siblings. Two open label trials found high dose vitamin D improves the core symptoms of autism in about 75% of autistic children. A few of the improvements were remarkable. The vitamin D doses used in these children were 300 IU/KG/day up to a maximum of 5000 IU/day (highest final 25(OH)D level reached was 45 ng/ml). The other study used 150,000 IU/month IM as well as 400 IU/day [highest final 25(OH)D level was 52 ng/ml]. These two open label trials were recently confirmed with a randomized controlled trial (RCT) using 300 IU/kg/day with a maximum of 5000 IU/day and resulted in effects similar to the two open label studies. In terms of prevention, a recent small study showed vitamin D supplementation during pregnancy (5000 IU/day) and during infancy and early childhood (1000 IU/day) significantly reduced the expected incidence of autism in mothers who already had one autistic child from 20% to 5%. Vitamin D is safe; for example, over the last 15 years, Poison Control reports there have been approximately 15,000 cases of vitamin D overdose. However only three of these 15,000 people developed clinical toxicity and no one died. Given those facts, practitioners might consider treating autism with 300 IU/kg/day, and seek to prevent autism by supplementing pregnant and lactating women (5000 IU/day) and infants and young children (150 IU/kg/day) checking 25(OH)D levels every 3 months. These doses will increase 25(OH)D blood levels to those recommended by the Endocrine Society. As the American Academy of Pediatrics recommends vitamin D supplementation during infancy and childhood, pediatricians and family practitioners should evaluate the current evidence on autism and vitamin D and act accordingly.

Exploratory Metabolomics Profiling in the Kainic Acid Rat Model Reveals Depletion of 25-Hydroxyvitamin D3 during Epileptogenesis

Currently, no reliable markers are available to evaluate the epileptogenic potential of a brain injury. The electroencephalogram is the standard method of diagnosis of epilepsy; however, it is not used to predict the risk of developing epilepsy. Biomarkers that indicate an individual's risk to develop epilepsy, especially those measurable in the periphery are urgently needed. Temporal lobe epilepsy (TLE), the most common form of acquired epilepsy, is characterized by spontaneous recurrent seizures following brain injury and a seizure-free "latent" period. Elucidation of mechanisms at play during epilepsy development (epileptogenesis) in animal models of TLE could enable the identification of predictive biomarkers. Our pilot study using liquid chromatography-mass spectrometry metabolomics analysis revealed changes (p-value ≤ 0.05, ≥1.5-fold change) in lipid, purine, and sterol metabolism in rat plasma and hippocampus during epileptogenesis and chronic epilepsy in the kainic acid model of TLE. Notably, disease development was associated with dysregulation of vitamin D3 metabolism at all stages and plasma 25-hydroxyvitamin D3 depletion in the acute and latent phase of injury-induced epileptogenesis. These data suggest that plasma VD3 metabolites reflect the severity of an epileptogenic insult and that a panel of plasma VD3 metabolites may be able to serve as a marker of epileptogenesis.

Evidence for the Importance of Vitamin D Status in Neurologic Conditions

OPINION STATEMENT

Vitamin D status has been proposed as relevant to many neurological disorders. Data suggest that vitamin D may be important for the development of the nervous system, and it also plays a role in neuroimmunology and neuroprotection. Lower levels of circulating 25-hydroxyvitamin D have been linked with increased risk of multiple sclerosis (MS) and Alzheimer's disease (AD). While people with amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD), and stroke have lower vitamin D levels than those without the diseases, it is unclear if this is because hypovitaminosis D contributes to disease risk or is a consequence of immobility and other factors caused by the disease. Lower levels of vitamin D have been associated with worse prognosis in MS, PD, ALS, and stroke, while no longitudinal studies have been performed to evaluate such an association in AD. Small pilot trials have been performed to evaluate vitamin D supplementation for some of these diseases, but there have been no phase III studies to support vitamin D supplementation in these patient populations; further, ideal levels of 25-hydroxyvitamin D are not known. Thus, while some expert panels or individuals have suggested routine testing and supplementation for patients with these neurological conditions, it is our opinion that there are currently insufficient data to support high-dose vitamin D supplementation to specifically treat or prevent these conditions.

Association between Vitamin D Receptor Gene Polymorphisms with Childhood Temporal Lobe Epilepsy

Vitamin D (VD) is implicated in multiple aspects of human physiology and vitamin D receptor (VDR) polymorphisms are associated with a variety of neuropsychiatric disorders. Although VD deficiency is highly prevalent in epilepsy patients and converging evidence indicates a role for VD in the development of epilepsy, no data is available on the possible relationship between epilepsy and genetic variations of VDR. In this study, 150 controls and 82 patients with temporal lobe epilepsy (TLE) were genotyped for five common VDR polymorphisms (Cdx-2, FokI, BsmI, ApaI and TaqI) by the polymerase chain reaction-ligase detection reaction method. Our results revealed that the frequency of FokI AC genotype was significantly higher in the control group than in the patients (p = 0.003, OR = 0.39, 95% CI = 0.21–0.73), whereas the AA genotype of ApaI SNP was more frequent in patients than in controls (p = 0.018, OR = 2.92, 95% CI = 1.2–7.1). However, no statistically significant association was found between Cdx-2, BsmI and TaqI polymorphisms and epilepsy. Additionally, in haplotype analysis, we found the haplotype GAT (BsmI/ApaI/TaqI) conferred significantly increased risk for developing TLE (p = 0.039, OR = 1.62, 95% CI = 1.02–2.56). As far as we know, these results firstly underline the importance of VDR polymorphisms for the genetic susceptibility to epilepsy.

Vitamin D supplementation in children with epilepsy and intellectual disability

BACKGROUND

Children with epilepsy and intellectual disability have an increased risk of vitamin D deficiency. In this patient group, it is neither clear which factors are associated with the level of 25-hydroxyvitamin D nor what the therapeutic results are when Dutch guidelines are followed.

METHODS

This retrospective study included 30 patients who, in October 2012, were residents of the children's wards of a tertiary epilepsy center in The Netherlands (Kempenhaeghe). From November 2012 onward they received cholecalciferol supplementation in doses that met or exceeded Dutch guidelines. At baseline, after 6, and 15 months, serum 25-hydroxyvitamin D concentration was measured.

RESULTS

At baseline, the vitamin D status in 11 (36.7%) residents was found to be deficient, in 10 (33.3%) to be insufficient and in 9 (30.0%) sufficient. Supplementation dose, diet, body mass index, intellectual disability, and mobility were significantly associated with baseline 25-hydroxyvitamin D concentrations. The mean 25-hydroxyvitamin D concentration increased significantly from 57.40 ± 22.00 nmol/L at baseline to 89.47 ± 26.77 nmol/L after 15 months (P < 0.001). In spite of supplementation ranging from 400 to 1200 IU/day, 64% of the residents in the deficient category and 30% of those with an insufficient level at baseline failed to attain a sufficient vitamin D status after 15 months.

CONCLUSIONS

Not all residents reached a sufficient vitamin D status after supplementation at least equal to the amount recommended by the Dutch guidelines. In a high-risk population, such as our residents, we advise monitoring 25-hydroxyvitamin D concentrations, adjusting supplementation accordingly and following patients to ensure they reach sufficiency.

Regulation of neurotropic signaling by the inducible, NF-kB-sensitive miRNA-125b in Alzheimer's disease (AD) and in primary human neuronal-glial (HNG) cells

Inducible microRNAs (miRNAs) perform critical regulatory roles in central nervous system (CNS) development, aging, health, and disease. Using miRNA arrays, RNA sequencing, enhanced Northern dot blot hybridization technologies, Western immunoblot, and bioinformatics analysis, we have studied miRNA abundance and complexity in Alzheimer's disease (AD) brain tissues compared to age-matched controls. In both short post-mortem AD and in stressed primary human neuronal-glial (HNG) cells, we observe a consistent up-regulation of several brain-enriched miRNAs that are under transcriptional control by the pro-inflammatory transcription factor NF-kB. These include miRNA-9, miRNA-34a, miRNA-125b, miRNA-146a, and miRNA-155. Of the inducible miRNAs in this subfamily, miRNA-125b is among the most abundant and significantly induced miRNA species in human brain cells and tissues. Bioinformatics analysis indicated that an up-regulated miRNA-125b could potentially target the 3'untranslated region (3'-UTR) of the messenger RNA (mRNA) encoding (a) a 15-lipoxygenase (15-LOX; ALOX15; chr 17p13.3), utilized in the conversion of docosahexaneoic acid into neuroprotectin D1 (NPD1), and (b) the vitamin D3 receptor (VDR; VD3R; chr12q13.11) of the nuclear hormone receptor superfamily. 15-LOX and VDR are key neuromolecular factors essential in lipid-mediated signaling, neurotrophic support, defense against reactive oxygen and nitrogen species (reactive oxygen and nitrogen species), and neuroprotection in the CNS. Pathogenic effects appear to be mediated via specific interaction of miRNA-125b with the 3'-UTR region of the 15-LOX and VDR messenger RNAs (mRNAs). In AD hippocampal CA1 and in stressed HNG cells, 15-LOX and VDR down-regulation and a deficiency in neurotrophic support may therefore be explained by the actions of a single inducible, pro-inflammatory miRNA-125b. We will review the recent data on the pathogenic actions of this up-regulated miRNA-125b in AD and discuss potential therapeutic approaches using either anti-NF-kB or anti-miRNA-125b strategies. These may be of clinical relevance in the restoration of 15-LOX and VDR expression back to control levels and the re-establishment of homeostatic neurotrophic signaling in the CNS.

Low vitamin D levels are common in patients with epilepsy

PURPOSE

Vitamin D is important for bone health, and vitamin D deficiency may contribute to other disorders (e.g., autoimmune, infections, cancer, degenerative, diabetic, and vascular). Enzyme-inducing antiepileptic drugs have been particularly implicated for osteoporosis risk given their effects on vitamin D. We examined the prevalence of vitamin D deficiency in adult epilepsy patients.

METHODS

We conducted an observational study of consecutive epilepsy patients treated by two clinicians at the Emory University Epilepsy Center from 2008 to 2011 in order to determine the frequency of low vitamin D levels and possible differential antiepileptic drug risks. Vitamin D 25-OH levels were categorized as low (<20 ng/ml), borderline (20-29 ng/ml), or normal (≥30 ng/ml). Antiepileptic drugs were categorized based on their enzyme inducing properties. Descriptive and inferential statistics were employed.

RESULTS

Vitamin D levels were obtained on 596 patients with epilepsy. Mean age was 41 years (SD=14; range=18-81); 56% were women. Race/ethnicity was 55% Caucasian, 34% Black, 2% Asian, and 7% Unknown. The mean vitamin D level was 22.5 (SD=11.9; range = <4 to 98), and 45% had level <20 ng/ml. Mean vitamin D levels (F=6.48, p=.002) and frequencies of vitamin D categories (p=.002, Chi square test) differed across the antiepileptic drug groups. Vitamin D deficiency was present in 54% of enzyme-inducing and 37% of non-enzyme-inducing antiepileptic drugs groups.

CONCLUSIONS

Vitamin D deficiency is common in patients with epilepsy on antiepileptic drugs. Monitoring of vitamin D should be considered as part of the routine management of patients with epilepsy.