Interweaving epilepsy and neurodegeneration: Vitamin E as a treatment approach

Aman B Upaganlawar, Nitu L Wankhede, Mayur B Kale, Mohit D Umare, Aayush Sehgal, Sukhbir Singh, Saurabh Bhatia, Ahmed Al-Harrasi, Agnieszka Najda, Renata Nurzyńska-Wierdak, Simona Bungau, Tapan Behl

Biomed Pharmacother . 2021 Nov;143:112146. doi: 10.1016/j.biopha.2021.112146. Epub 2021 Sep 8.

Abstract

Epilepsy is the most common neurological disorder, affecting nearly 50 million people worldwide. The condition can be manifested either due to genetic predisposition or acquired from acute insult which leads to alteration of cellular and molecular mechanisms. Evaluating the latest and the current knowledge in regard to the mechanisms underlying molecular and cellular alteration, hyperexcitability is a consequence of an imbalanced state wherein enhance excitatory glutamatergic and reduced inhibitory GABAergic signaling is considered to be accountable for seizures associated damage. However, neurodegeneration contributing to epileptogenesis has become increasingly appreciated. The components at the helm of neurodegenerative alterations during epileptogenesis include GABAergic neuronal and receptor changes, neuroinflammation, alteration in axonal transport, oxidative stress, excitotoxicity, and other cellular as well as functional changes. Targeting neurodegeneration with vitamin E as an antioxidant, anti-inflammatory and neuroprotective may prove to be one of the therapeutic approaches useful in managing epilepsy. In this review, we discuss and converse about the seizure-induced episodes as a link for the development of neurodegenerative and pathological consequences of epilepsy. We also put forth a summary of the potential intervention with vitamin E therapy in the management of epilepsy.

Read More

Stress-activated leukocyte 12/15-lipoxygenase metabolite enhances struggle behaviour and tocotrienols relieve stress-induced behaviour alteration

Mototada Shichiri, Noriko Ishida, Yoshinori Aoki, Taisuke Koike, Yoshihisa Hagihara

Free Radic Biol Med . 2021 Nov 1;175:171-183. doi: 10.1016/j.freeradbiomed.2021.08.236. Epub 2021 Aug 30.

Abstract

Stress induces emotional arousal causing anxiety, irritability, exaggerated startle behaviour, and hypervigilance observed in patients with trauma and stress-related mental disorders, including acute stress disorder and post-traumatic stress disorder. Central norepinephrine release promotes stress-induced emotional arousal. However, the regulator of emotional arousal remains unknown. Here, we show that the arachidonate-derived metabolite produced by stress-activated leukocyte 12/15-lipoxygenase is remarkably elevated in the plasma and upregulates the central norepinephrine release, resulting in the enhancement of the struggle behaviour (= escape behaviour) in the tail suspension test. Struggle behaviour is mimicking a symptom of emotional arousal. This stress-induced struggle behaviour was absent in 12/15-lipoxygenase deficient mice; however, intravenous administration of a 12/15-lipoxygenase metabolite to these mice after stress exposure rekindled the struggle behaviour. Furthermore, tocotrienols and geranylgeraniol reduced stress-induced 12/15-lipoxygenase metabolite production and suppressed the struggle behaviour. Our findings indicate that arachidonate-derived 12/15-lipoxygenase metabolite is involved in the regulation of stress-enhanced central norepinephrine release and struggle behaviour. In addition, we propose 12/15-lipoxygenase as a potential therapeutic target for the treatment of emotional arousal observed in stress-related mental disorders.

Read More 

Enjoy Carefully: The Multifaceted Role of Vitamin E in Neuro-Nutrition

Liesa Regner-Nelke, Christopher Nelke, Christina B Schroeter, Rainer Dziewas, Tobias Warnecke, Tobias Ruck, Sven G Meuth

Int J Mol Sci . 2021 Sep 18;22(18):10087. doi: 10.3390/ijms221810087.

Abstract

Vitamin E is often associated with health benefits, such as antioxidant, anti-inflammatory and cholesterol-lowering effects. These properties make its supplementation a suitable therapeutic approach in neurodegenerative disorders, for example, Alzheimer’s or Parkinson’s disease. However, trials evaluating the effects of vitamin E supplementation are inconsistent. In randomized controlled trials, the observed associations often cannot be substantiated. This could be due to the wide variety of study designs regarding the dosage and duration of vitamin E supplementation. Furthermore, genetic variants can influence vitamin E uptake and/or metabolism, thereby distorting its overall effect. Recent studies also show adverse effects of vitamin E supplementation regarding Alzheimer’s disease due to the increased synthesis of amyloid β. These diverse effects may underline the inhomogeneous outcomes associated with its supplementation and argue for a more thoughtful usage of vitamin E. Specifically, the genetic and nutritional profile should be taken into consideration to identify suitable candidates who will benefit from supplementation. In this review, we will provide an overview of the current knowledge of vitamin E supplementation in neurodegenerative disease and give an outlook on individualized, sustainable neuro-nutrition, with a focus on vitamin E supplementation.

Read More

Plasma antioxidants and risk of dementia in older adults

Manja Koch, Jeremy D Furtado, Héléne Toinét Cronjé, Steven T DeKosky, Annette L Fitzpatrick, Oscar L Lopez, Lewis H Kuller, Kenneth J Mukamal, Majken K Jensen

Alzheimers Dement (N Y) . 2021 Sep 5;7(1):e12208. doi: 10.1002/trc2.12208. eCollection 2021.

Abstract

Introduction: Plant-based diets rich in fruits and vegetables have been associated with lower risk of dementia, but the specific role of antioxidants, a key class of bioactive phytochemicals, has not been well ascertained.

Methods: We measured antioxidants in a case-cohort study nested within the Ginkgo Evaluation of Memory Study. We included 996 randomly selected participants and 521 participants who developed dementia, of which 351 were diagnosed with Alzheimer’s disease (AD) during a median of 5.9 years of follow-up. We measured baseline plasma levels of retinol, α-, and γ-tocopherol; zeaxanthin and lutein (combined); beta-cryptoxanthin; cis-lycopene; trans-lycopene; α-carotene; and trans-β-carotene by organic phase extraction followed by chromatographic analysis and related these to neurologist-adjudicated risks of all-cause dementia and AD.

Results: Plasma retinol, α-, and γ-tocopherol, and carotenoids were not significantly related to risk of dementia or AD. Associations were not significant upon Bonferroni correction for multiple testing and were consistent within strata of sex, age, apolipoprotein E ε4 genotype, mild cognitive impairment at baseline, and intake of multivitamin, vitamin A or β-carotene, or vitamin E supplements. Higher trans-β-carotene tended to be related to a higher risk of dementia (adjusted hazard ratio [HR] per 1 standard deviation [SD] higher trans-β-carotene: 1.10; 95% confidence interval [CI]: 1.00, 1.20) and α-carotene tended to be associated with higher risk of AD only (adjusted HR per 1 SD higher α-carotene: 1.15; 95% CI: 1.02, 1.29).

Discussion: Plasma antioxidants were not significantly associated with risk of dementia or AD among older adults. Similar studies in younger populations are required to better understand the association between plasma antioxidants and dementia risk.

Read More

The effect of α-tocopherol, α- and γ-tocotrienols on amyloid-β aggregation and disaggregation in vitro

Nor Faeizah Ibrahim, Hamizah Shahirah Hamezah, Daijiro Yanagisawa, Mayumi Tsuji, Yuji Kiuchi, Kenjiro Ono, Ikuo Tooyama

Biochem Biophys Rep . 2021 Sep 10;28:101131. doi: 10.1016/j.bbrep.2021.101131. eCollection 2021 Dec.

Abstract

One of the neuropathological hallmarks of Alzheimer’s disease (AD)-causing neurodegeneration and consequent memory deterioration, and eventually, cognitive decline-is amyloid-β (Aβ) aggregation forming amyloid plaques. Our previous study showed the potential of a tocotrienol-rich fraction-a mixture of naturally occurring of vitamin E analogs-to inhibit Aβ aggregation and restore cognitive function in an AD mouse model. The current study examined the effect of three vitamin E analogs-α-tocopherol (α-TOC), α-tocotrienol (α-T3), and γ-tocotrienol (γ-T3)-on Aβ aggregation, disaggregation, and oligomerization in vitro. Thioflavin T (ThT) assay showed α-T3 reduced Aβ aggregation at 10 μM concentration. Furthermore, both α-T3 and γ-T3 demonstrated Aβ disaggregation, as shown by the reduction of ThT fluorescence. However, α-TOC showed no significant effect. We confirmed the results for ThT assays with scanning electron microscopy imaging. Further investigation in photo-induced cross-linking of unmodified protein assay indicated a reduction in Aβ oligomerization by γ-T3. The present study thus revealed the individual effect of each tocotrienol analog in reducing Aβ aggregation and oligomerization as well as disaggregating preformed fibrils.

Read More

Role of Vitamin E and the Orexin System in Neuroprotection

Maria Ester La Torre, Ines Villano, Marcellino Monda, Antonietta Messina, Giuseppe Cibelli, Anna Valenzano, Daniela Pisanelli, Maria Antonietta Panaro, Nicola Tartaglia, Antonio Ambrosi, Marco Carotenuto, Vincenzo Monda, Giovanni Messina, Chiara Porro

Brain Sci . 2021 Aug 20;11(8):1098. doi: 10.3390/brainsci11081098.

Abstract

Microglia are the first line of defense at the level of the central nervous system (CNS). Phenotypic change in microglia can be regulated by various factors, including the orexin system. Neuroinflammation is an inflammatory process mediated by cytokines, by the lack of interaction of specific receptors such as the OX2-OX2R complex, caused by systemic tissue damage or, more often, associated with direct damage to the CNS. Chronic activation of microglia could lead to long-term neurodegenerative diseases. This review aims to explore how tocopherol (vitamin E) and the orexin system may play a role in the prevention and treatment of microglia inflammation and, consequently, in neurodegenerative diseases thanks to its antioxidant properties. The results of animal and in vitro studies provide evidence to support the use of tocopherol for a reduction in microglia inflammation as well as a greater activation of the orexinergic system. Although there is much in vivo and in vitro evidence of vitamin E antioxidant and protective abilities, there are still conflicting results for its use as a treatment for neurodegenerative diseases that speculate that vitamin E, under certain conditions or genetic predispositions, can be pro-oxidant and harmful.

Read More

Dietary intake of tocopherols and risk of incident disabling dementia

Shoko Aoki, Kazumasa Yamagishi, Koutatsu Maruyama, Rie Kishida, Ai Ikeda, Mitsumasa Umesawa, Cui Renzhe, Yasuhiko Kubota, Mina Hayama-Terada, Yuji Shimizu, Isao Muraki, Hironori Imano, Tomoko Sankai, Takeo Okada, Akihiko Kitamura, Masahiko Kiyama, Hiroyasu Iso

Sci Rep . 2021 Aug 12;11(1):16429. doi: 10.1038/s41598-021-95671-7.

Abstract

Tocopherols, strong antioxidants, may be useful in preventing dementia, but the epidemiological evidence is insufficient. We performed a community-based follow-up study of Japanese, the Circulatory Risk in Community Study, involving 3739 people aged 40-64 years at baseline (1985-1999). Incident disabling dementia was followed up from 1999 through 2020. For subtype analysis, we classified disabling dementia into that with and that without a history of stroke. Dietary intake of tocopherols (total, α, β, γ, and δ) were estimated using 24-h recall surveys. During a median follow-up of 19.7 years, 670 cases of disabling dementia developed. Total tocopherol intake was inversely associated with risk of disabling dementia with multivariable hazard ratios (95% confidence intervals) of 0.79 (0.63-1.00) for the highest versus lowest quartiles of total tocopherol intake (P for trend = 0.05). However, the association was strengthened when further adjusted for α-linolenic acid intake (Spearman correlation with total tocopherol intake = 0.93), with multivariable hazard ratios of 0.50 (0.34-0.74) (P for trend = 0.001) but was weakened and nonsignificant when further adjusted for linoleic acid intake (Spearman correlation with total tocopherol intake = 0.92), with multivariable hazard ratios of 0.69 (0.47-1.01) (P for trend = 0.05). Similar but nonsignificant inverse associations were observed for α-, γ-, and δ-tocopherols but not for β-tocopherol. These results were similar regardless of the presence of a history of stroke. Dietary tocopherol intake was inversely associated with risk of disabling dementia, but its independent effect was uncertain owing to a high intercorrelation of α-linolenic linoleic acids with total tocopherol intake. Even with such confounding, a diet high in tocopherols may help prevent the onset of dementia.

Read More

Effects of Co-administration of Vitamin E and Lithium Chloride on Chronic Constriction Injury-induced Neuropathy in Male Wistar Rats: Focus on antioxidant and anti-inflammatory mechanisms

Kingsley Dominic Esu, Ahmed Olalekan Bakare, Bamidele Victor Owoyele

Pain Pract . 2021 Aug 5. doi: 10.1111/papr.13064. Online ahead of print.

Abstract

Objectives: This study investigated the antinociceptive effects of co-administration of lithium chloride (LiCl) and vitamin E (Vit. E) on chronic constriction injury (CCI)-induced peripheral neuropathy in male Wistar rats. It further explored the anti-inflammatory and neuroprotective properties of LiCl and Vit. E which may be complementary to the antinociceptive effects of the two substances.

Methods: Thirty-six male Wistar rats, 190.00 ± 10.00 g of body weight (b.w) were randomly assigned to six experimental groups and administered with either normal saline, Vit. E, LiCl, or their combination, once daily for twenty-one (21) days. CCI was used to induce NP and mechanical allodynia was assessed using von Frey filaments and pinprick test. Open field maze (OFM) was used to assess the exploratory behaviour. Biochemical parameters were assessed in the dorsal root ganglion (DRG) after twenty-one days of treatment.

Results: Mechanical allodynia was developed in rats following CCI. Co-administration of LiCl and Vit.E. synergistically reduced mechanical hyperalgesia in rats which were significantly different compared with the single administration of either Vit.E. or LiCl. Combined doses of Vit.E. and LiCl significantly increases the explorative behaviour in the OFM. CCI increased malondialdehyde (MDA), tumour necrotic factor-alpha (TNF-α), calcitonin gene-related polypeptide (CGRP), calcium ion (Ca2+ ), and reduced superoxide dismutase (SOD) activities. Co-administration of LiCl and Vit.E. significantly reduced MDA, TNF-α, but increased SOD compared with ligated control.

Discussion: The findings revealed that the synergistic effects of the co-administration of Vit. E and LiCl in ameliorating neuropathic pain are mediated by their anti-inflammatory and antioxidant properties.

Read More

Increased α-tocopherol metabolism in horses with equine neuroaxonal dystrophy

Erin N Hales, Hadi Habib, Gianna Favro, Scott Katzman, R Russell Sakai, Sabin Marquardt, Matthew H Bordbari, Brittni Ming-Whitfield, Janel Peterson, Anna R Dahlgren, Victor Rivas, Carolina Alanis Ramirez, Sichong Peng, Callum G Donnelly, Bobbi-Sue Dizmang, Angelica Kallenberg, Robert Grahn, Andrew D Miller, Kevin Woolard, Benjamin Moeller, Birgit Puschner, Carrie J Finno

J Vet Intern Med . 2021 Jul 31. doi: 10.1111/jvim.16233. Online ahead of print.

Abstract

Background: Equine neuroaxonal dystrophy/equine degenerative myeloencephalopathy (eNAD/EDM) is an inherited neurodegenerative disorder associated with a vitamin E deficiency within the first year of life. Vitamin E consists of 8 isoforms metabolized by the CYP4F2 enzyme. No antemortem diagnostic test currently exists for eNAD/EDM.

Hypothesis/objectives: Based on the association of α-tocopherol deficiency with the development of eNAD/EDM, we hypothesized that the rate of α-tocopherol, but not γ-tocopherol or tocotrienol metabolism, would be increased in eNAD/EDM-affected horses.

Animals: Vitamin E metabolism: Proof of concept (POC) study; eNAD/EDM-affected (n = 5) and control (n = 6) horses. Validation study: eNAD/EDM-affected Quarter Horses (QHs; n = 6), cervical vertebral compressive myelopathy affected (n = 6) horses and control (n = 29) horses. CYP4F2 expression and copy number: eNAD/EDM-affected (n = 12) and age- and sex-matched control (n = 11-12) horses.

Methods: The rates of α-tocopherol/tocotrienol and γ-tocopherol/tocotrienol metabolism were assessed in equine serum (POC and validation) and urine (POC only) using liquid chromatography tandem mass spectrometry (LC-MS/MS). Quantitative reverse-transcriptase PCR (qRT-PCR) and droplet digital (dd)-PCR were used to assay expression and genomic copy number of a CYP4F2 equine ortholog.

Results: Metabolic rate of α-tocopherol was increased in eNAD/EDM horses (POC,P < .0001; validation, P = .03), with no difference in the metabolic rate of γ-tocopherol. Horses with eNAD/EDM had increased expression of the CYP4F2 equine orthologue (P = .02) but no differences in copy number.

Conclusions and clinical importance: Increased α-tocopherol metabolism in eNAD/EDM-affected QHs provides novel insight into alterations in vitamin E processing in eNAD/EDM and highlights the need for high-dose supplementation to prevent the clinical phenotype in genetically susceptible horses.

Read More

Effects of vitamin E on neurodegenerative diseases: an update

Mehmet Arif Icer, Neslihan Arslan, Makbule Gezmen-Karadag

Acta Neurobiol Exp (Wars) . 2021;81(1):21-33. doi: 10.21307/ane-2021-003.

Abstract

Vitamin E deficiency is associated with many neurological problems. Although the mechanisms of vitamin E action in neurodegenerative diseases are not clear, there are many possible mechanisms. Examples of such mechanisms are the protective effects of vitamin E against oxidative stress damage and its suppressive role in the expression of many genes involved in the development of neurodegeneration. Many studies have evaluated the relationship between vitamin E intake or vitamin E levels in body fluids and neurodegenerative diseases. Some studies concluded that vitamin E can play a protective role in neurodegeneration with respect to diseases such as Alzheimer’s disease (AD), Parkinson’s disease (PD), stroke and amyotrophic lateral sclerosis (ALS). Vitamin E supplementation was also associated with risk factors for some neurodegenerative diseases. In this review, we discuss the possible effects of vitamin E on the development and course of AD, PD, stroke and ALS, and the potential mechanisms involved.

Vitamin E deficiency is associated with many neurological problems. Although the mechanisms of vitamin E action in neurodegenerative diseases are not clear, there are many possible mechanisms. Examples of such mechanisms are the protective effects of vitamin E against oxidative stress damage and its suppressive role in the expression of many genes involved in the development of neurodegeneration. Many studies have evaluated the relationship between vitamin E intake or vitamin E levels in body fluids and neurodegenerative diseases. Some studies concluded that vitamin E can play a protective role in neurodegeneration with respect to diseases such as Alzheimer’s disease (AD), Parkinson’s disease (PD), stroke and amyotrophic lateral sclerosis (ALS). Vitamin E supplementation was also associated with risk factors for some neurodegenerative diseases. In this review, we discuss the possible effects of vitamin E on the development and course of AD, PD, stroke and ALS, and the potential mechanisms involved.

Read More