The Effects of Tocotrienol-Rich Vitamin E (Tocovid) on Diabetic Neuropathy: A Phase II Randomized Controlled Trial

Yeek Tat Ng, Sonia Chew Wen Phang, Gerald Chen Jie Tan, En Yng Ng, Nevein Philip Botross Henien, Uma Devi M Palanisamy, Badariah Ahmad, Khalid Abdul Kadir

Nutrients . 2020 May 23;12(5):1522. doi: 10.3390/nu12051522.

Abstract

Chronic hyperglycemia increases oxidative stress, activates inflammatory pathways and reduces nerve growth factor (NGF) among diabetic patients, which contribute to development of diabetic peripheral neuropathy (DPN). Tocotrienol-Rich Vitamin E (Tocovid) possesses potent antioxidant and anti-inflammatory properties which are postulated to target these pathogeneses in order to ameliorate DPN. This study aims to evaluate the effects of Tocovid on nerve conduction parameters and serum biomarkers among diabetic patients. This multicenter, prospective, randomized, double-blind, placebo-controlled clinical trial was conducted on 80 eligible participants. The intervention group (n = 39) was randomly allocated to receive 200 mg of Tocovid twice a day, and the control group (n = 41) received placebo twice a day. At the end of eight weeks, the nerve conduction parameters, as assessed by nerve conduction study, as well as serum biomarkers (NGF, malondialdehyde, vascular cell adhesion molecule 1, tumor necrosis factor receptor 1 and thromboxane B2) were compared between the two groups. Compared to placebo, Tocovid significantly improves the nerve conduction velocities of all nerves (+1.25 m/s, interquartile range [IQR] 3.35, p < 0.001, median nerve; +1.60 m/s, IQR 1.80, p < 0.001, sural nerve; +0.75 m/s, IQR 2.25, p < 0.001, tibial nerve). Meanwhile, the levels of serum NGF were significantly higher in the Tocovid group as compared to placebo at eight weeks post-intervention. Participants receiving Tocovid illustrated highly significant improvement in terms of nerve conduction velocities for all nerves tested after eight weeks of supplementation. In addition, Tocovid supplementation elevated the levels of serum NGF, in which its increase is postulated to reflect enhanced neuronal functions. This novel finding suggests that Tocovid could be a disease-modifying agent targeting serum NGF to improve nerve conduction velocities.

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Vitamin E

Jacquelyn Medina, Vikas Gupta

In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan. 2020 May 21.

Excerpt

Vitamin E or tocopherol is a fat-soluble vitamin functioning as an antioxidant, protecting the cell membrane. As with all vitamins, the body does not form vitamin E. It solely forms from photosynthetic processes of plants, and therefore must be consumed from outside sources in small quantities. It is found abundantly in olive and sunflower oils, as well as nuts, soybeans, avocados, wheat, and green leafy vegetables.

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Effect of High Fructose-Induced Metabolic Syndrome on Tissue Vitamin E and Lipid Peroxide Levels in Rats

Akira Kitagawa, Yoshiji Ohta, Koji Ohashi, Koji Yashiro, Kenji Fukuzawa

J Nutr Sci Vitaminol (Tokyo) . 2020;66(2):200-206. doi: 10.3177/jnsv.66.200.

Abstract

In the present study, we examined the effect of high fructose-induced metabolic syndrome (MetS) on tissue vitamin E and lipid peroxide (LPO) levels in rats. Feeding of a diet containing 60% fructose (HFD) to Wistar rats for 2, 4, and 6 wk caused week-dependent increases in HOMA-IR score and serum insulin, triglyceride, total cholesterol, and free fatty acid concentrations. Each week HFD feeding increased serum vitamin E concentration. Six-week HFD feeding reduced vitamin E status (the serum ratio of vitamin E/triglyceride+total cholesterol). Four- and 6-wk HFD feeding increased serum LPO concentration. Two-week HFD feeding increased liver, heart, kidney, and skeletal muscle (SM) vitamin E contents and decreased white adipose tissue (WAT) vitamin E content. Four- and 6-wk HFD feeding further reduced WAT vitamin E content without affecting the increased kidney and SM vitamin E contents. Six-week HFD feeding reduced the increased liver and heart vitamin E contents below the level of non-HFD feeding. Four-week HFD feeding increased heart and WAT LPO contents. Six-week HFD feeding increased liver LPO content and further increased heart and WAT LPO contents. Kidney and SM LPO contents remained unchanged. These results indicate that HFD-rats with early MetS have increased liver, kidney, heart, and SM vitamin E contents and decreased WAT vitamin E content under unchanged tissue LPO content and vitamin E status, while HFD-fed rats with progressed MetS have both decreased liver, heart, and WAT vitamin E contents under increased tissue LPO content and disrupted vitamin E status.

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E-Cigarettes, Vaping Devices, and Acute Lung Injury

Nathan K Cobb, Jigna N Solanki

Respir Care . 2020 May;65(5):713-718. doi: 10.4187/respcare.07733.

Abstract

“E-cigarettes” are a class of consumer devices designed to deliver drugs, primarily nicotine or marijuana oils, to the lung by vaporization. Regulation of the devices in the United States is relatively minimal, and research on both epidemiology and potential toxicity has focused on nicotine devices. In 2019, an outbreak of an acute respiratory illness in the United States was traced back to the contamination of e-cigarette fluids with vitamin E acetate, which had been used to disguise the dilution of marijuana oils. The outbreak, termed “e-cigarette or vaping associated lung injury” by the U.S. Centers for Disease Control, was characterized by pulmonary infiltrates and hypoxia, which usually required hospitalization and, often, admission to ICUs. The syndrome sickened >2,600 people, mostly young men, and killed >50 people before it began to abate 6 months later. No current regulations exist to prevent a similar event with the same or different chemical contaminants. Absent such regulation, respiratory practitioners should be prepared to evaluate, identify, and treat future cases of acute lung toxicity from e-cigarettes.

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Comparative Efficacy of Vitamin Supplements on Prevention of Major Cardiovascular Disease: Systematic Review With Network Meta-Analysis

Ji Han, Chunyang Zhao, Jiayi Cai, Yu Liang

Complement Ther Clin Pract . 2020 May;39:101142. doi: 10.1016/j.ctcp.2020.101142. Epub 2020 Mar 14.

Abstract

Background: Vitamins are commonly used in the prevention of major cardiovascular disease. However, the efficacy and optimum choice remain controversial.

Objective: To compare and rank the relative efficacy among all available vitamin preparations for cardiovascular disease through a network meta-analysis.

Methods: Eligible studies were identified by searching PubMed, Embase, Medline, Cochrane library and Web of Science for randomized controlled trials. A random effects model was applied within a frequentist framework.

Results: Forty-two articles (45 comparisons, 384,248 participants), including nine vitamin interventions, were identified. Vitamin D had the highest probability of being ranked best in effectiveness (0.84 [0.72, 0.98]) on prevention of cardiovascular events. With regard to reducing death of cardiovascular disease rate, vitamin E was considered better efficacy.

Conclusions: Vitamin B, D and E could reduce the incidence of cardiovascular events to varying degrees. At the same time, the combination of vitamins can not show improvement on the efficacy.

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Non-alcoholic Fatty Liver Disease and Diabetes Mellitus

Gebran Khneizer, Syed Rizvi, Samer Gawrieh

Adv Exp Med Biol . 2020 May 19. doi: 10.1007/5584_2020_532.

Abstract

Nonalcoholic fatty liver disease (NAFLD) has emerged as the leading liver disease globally. NAFLD patients can have a progressive phenotype, non-alcoholic steatohepatitis (NASH) that could lead to cirrhosis, liver failure and cancer. There is a close bi-directional relationship between NAFLD and type 2 diabetes mellitus (T2DM); NAFLD increases the risk for T2DM and its complications whereas T2DM increases the severity of NAFLD and its complications. The large global impact of NAFLD and T2DM on healthcare systems requires a paradigm shift from specialty care to early identification and risk stratification of NAFLD in primary care and diabetes clinics. Approach to diagnosis, risk stratification and management of NAFLD is discussed. In addition to optimizing the control of coexisting cardiometabolic comorbidities, early referral of NAFLD patients at high risk of having NASH or significant fibrosis to hepatology specialist care may improve management and allow access for clinical trials. Lifestyle modifications, vitamin E, pioglitazone and metformin are currently available options that may benefit patients with T2DM and NAFLD. The burst of clinical trials investigating newer therapeutic agents for NAFLD and NASH offer hope for new, effective and safe therapies in the near future.

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The Role of Oral Vitamin E Supplementation in Reducing Nitrosative Stress in Adult Treated Patients With Celiac Disease: A Pilot Study

Agnieszka Piątek-Guziewicz, Agnieszka Dąbek, Magdalena Przybylska-Feluś, Paweł Zagrodzki, Tomasz Mach, Małgorzata Zwolińska-Wcisło

Pol Arch Intern Med . 2020 May 19. doi: 10.20452/pamw.15369. Online ahead of print.

Abstract

The pathogenesis of celiac disease (CD) is complex and has not been fully elucidated. It has been postulated that oxidative stress, because of an increase in the concentration of reactive oxygen species and antioxidant capacity reduction, is one of the processes possibly involved in gliadin toxicity. Oxidative imbalance induced by gliadin peptides in enterocytes leads to the activation of the transcription of proinflammatory cytokines and enzymes, such as inducible nitric oxide synthase (iNOS), which in turn causes an increased production of nitric oxide (NO) metabolites favoring oxidative stress. Based on the our previous study, we hypothesized that persistent nitrosative stress despite gluten-free diet (GFD) may be responsible for persistent histopathologic changes and that GFD is only partially able to improve oxidative imbalance. Hence, serum NO levels seem to be useful as a marker of treatment efficacy, and alterations in these levels could indicate CD activity. It is possible that oral antioxidant supplementation may decrease the toxic effects of peptides. In the current study, we aimed to evaluate the effect of treatment with oral vitamin E on oxidative imbalance in adult patients with CD on GFD. For that purpose, we assessed the fasting plasma levels of nitrate as a marker of endogenous NO production and oxidative stress. Moreover, we monitored the individual components of antioxidant capacity. To the best of our knowledge, this is the first study evaluating the effects of oral vitamin E supplementation on oxidative imbalance in patients with CD.

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Nodular Panniculitis in a Cat With High Alpha Tocopherol Concentration in Serum

Martin Steffl, Nadine Nautscher, Alexander Kröpfl, Michael Granvogl

Vet Med Sci . 2020 May 18. doi: 10.1002/vms3.286. Online ahead of print.

Abstract

A 5-year-old male neutered domestic shorthair cat suffered from recurrent solitary nodules in different subcutaneous body regions. Nodules were surgically removed and each time histopathological diagnosis was fat necrosis and fibrosing to pyogranulomatous panniculitis. After the second surgery the alpha (α)-tocopherol concentration in serum of the cat was examined and the result (21 mg/L) exceeded the upper limit of the reference interval (3-11 mg/L). Vitamin E amount in diet fed solely in the past was checked as studies have shown that vitamin E amounts in food significantly influence vitamin E concentrations in serum. For comparative purposes, α-tocopherol concentrations were determined in sera of healthy control cats. Additionally, vitamin E amount in wet food from different manufacturers was analysed using gas chromatography coupled to mass spectrometry (GC-MS). The results showed that the diet did not have higher vitamin E amounts compared to other diets. All control cats had similar high serum α-tocopherol concentrations. We conclude that panniculitis can occur despite high serum α-tocopherol concentrations in cats. Further studies are needed to redefine reference values of α-tocopherol in serum of cats.

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Improving tumor hypoxia and radiotherapy resistance via in situ nitric oxide release strategy

Tu J, Tu K, Xu H, Wang L, Yuan X, Qin X, Kong L, Chu Q, Zhang Z

Eur J Pharm Biopharm. 2020 May;150:96-107. doi: 10.1016/j.ejpb.2020.03.003. Epub 2020 Mar 6.

Abstract

Radiation therapy remains one of the main treatments for cancer. However, conventional radiotherapy not only manifests a low radiation accumulation in the tumor site, but also displays numerous negative effects. The most serious clinical problem is the radiotherapy resistance leading to cancer deterioration. As an important gaseous signal molecule, nitric oxide (NO) has been widely studied for its role in regulating angiogenesis, improving hypoxia, and inhibiting tumor growth. However, due to the unstable characteristic, the application of NO in cancer therapy is still limited. Here, we designed a micellar system formed by a NO donor, D-α-Tocopheryl polyethylene glycol 1000 succinate (TPGS)-NO, for enabling sustained NO release to efficiently deliver NO into the tumor area. TPGS-NO could accumulate in the tumor site for extended circulation, thereby releasing NO to exert antitumor effects and enhance radiotherapy effects under low-oxygen conditions. It demonstrated the increased sensitivity of radiotherapy through enhancing tumor angiogenesis appropriately reducing tumor area hypoxia, which significantly induced tumor cell apoptosis and inhibited its repair during radiation. This work may show great potential in synergistic radiotherapy against cancer by facile NO donor administration.

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The simultaneous quantification of phytosterols and tocopherols in liposomal formulations using validated atmospheric pressure chemical ionization- liquid chromatography -tandem mass spectrometry

Poudel A, Gachumi G, Badea I, Bashi ZD, El-Aneed A

J Pharm Biomed Anal. 2020 May 10;183:113104. doi: 10.1016/j.jpba.2020.113104. Epub 2020 Jan 9.

Abstract

A novel liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed and validated to simultaneously quantify phytosterols (brassicasterol, campesterol, stigmasterol and β-sitosterol) and tocopherols (alpha, beta, gamma and delta) entrapped in the lipid bilayer of a liposomal formulation. Apart from liposomes (a pharmaceutical product), the developed method was able to quantify target analytes in agricultural products, thus showing wide applications. Atmospheric pressure chemical ionization (APCI) was employed due to the enhanced ionization of phytosterols and tocopherols in comparison to electrospray ionization. Unlike published work, the chromatographic conditions were modified to simplify the analytical approach. For the first time, a simple isocratic elution (acetonitrile:methanol 99:1 v/v) was utilized for the separation of four phytosterols and four tocopherols in a single run. A substantially better baseline separation of phytosterols were obtained in comparison to reported methods by using poroshell C18 column. The method has a total run time of 7 min, which is the shortest run time among all reported quantitative methods for the simultaneous determination of four phytosterols and four tocopherols. Calibration curves for all phytosterols were linear in the range of 0.05-10 μg/mL. In the case of tocopherols, alpha tocopherol showed linear response in the range of 0.25-10 μg/mL. However, gamma and delta tocopherols exhibited quadratic relationship in the same concentration range (0.25-10 μg/mL). Validation parameters met the International Conference on Harmonization (ICH) guidelines in terms of selectivity, accuracy, precision, repeatability, sensitivity, matrix effects, dilution integrity and stability. The method was, for the first time, successfully applied for the quantifying phytosterols and tocopherols entrapped inside liposomes. An interesting chromatographic phenomenon was observed during sample analysis. Alpha tocopherol (entrapped in the liposomal lipid bilayer) was found to elute at two retention times, 2.53 min and 3.60 min. Such dual separation was not observed in calibration standards and quality controls. It was concluded that the chiral recognition ability of liposomes made up of phosphatidylcholine separated the enantiomers of alpha tocopherol, giving rise to two peaks at two different retention time. To sum, the reported novel LC-MS/MS method addresses three major analytical shortcomings, namely i)longer run time, ii)complex gradient elution and iii)poor baseline separation of phytosterols and tocopherols.

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