There is a longstanding debate as to whether taking vitamin E supplements increases or decreases a person’s risk of developing cancer. A new study suggests that both outcomes are a possibility and also explains why.
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Vitamins E and C prevent apoptosis of testicular and ovarian tissues following mancozeb exposure in the first-generation mouse pups
Mahdi H, Tahereh H, Esmaiel S, Massood E
Toxicol Ind Health. 2019 Feb;35(2):136-144. doi: 10.1177/0748233718818692. Epub 2019 Jan 16.
Abstract
The aim of this study was to evaluate the role of apoptosis in the first-generation pups’ testicular and ovarian tissue changes following mancozeb (MNZ) administration during intrauterine and lactating periods and also the preventive effect of the co-administration of vitamins E and C on these changes. Naval Medical Research Institute (NMRI) pregnant mice were randomly divided into six groups: control, vehicle, MNZ, vitamin E plus MNZ, vitamin C plus MNZ and vitamins E and C plus MNZ. Administered doses of MNZ and vitamins E and C were 500, 200 and 100 mg/kg of body weight, respectively. These agents were administered to the animals by oral gavage every 2 days. Vitamin treatment was carried out 30 min prior to MNZ administration. Treatment was started on the second day of gestation and continued until weaning. Separated testes and ovaries of animals were prepared for apoptosis detection by terminal deoxynucleotidyl transferase end-labeling (TUNEL) staining. The percentage of TUNEL-positive cells was reported using the 4,6-diamidino-2-phenylindole method. As compared to the control and vehicle groups, MNZ induced a significant increase ( p < 0.001) in the number of TUNEL-positive cells. The administration of both vitamins E and C alone and together significantly ( p < 0.001) prevented the apoptotic impacts of MNZ. The preventive effect of the co-administration of these vitamins on the ovary was greater compared to the single administration of vitamins E ( p < 0.001) or C ( p < 0.001). Meanwhile, the results revealed the stronger preventive effect of vitamin C as compared to E on testicular tissue ( p < 0.05). The apoptotic impact of MNZ exposure during intrauterine and lactating periods on first-generation testicular and ovarian tissues was significant. The co-administration of vitamins E and C could prevent MNZ-induced testicular and ovarian changes.
10 foods rich in vitamin E
Vitamin E is a fat-soluble compound with antioxidant properties. Getting enough vitamin E is essential for the immune system, blood vessel health, and keeping the skin youthful.
δ-Tocotrienol induces apoptosis, involving endoplasmic reticulum stress and autophagy, and paraptosis in prostate cancer cells
Fontana F, Moretti RM, Raimondi M, Marzagalli M, Beretta G, Procacci P, Sartori P, Montagnani Marelli M, Limonta P
Cell Prolif. 2019 Feb 4:e12576. doi: 10.1111/cpr.12576. [Epub ahead of print]
Abstract
OBJECTIVES:
Prostate cancer, after the phase of androgen dependence, may progress to the castration-resistant prostate cancer (CRPC) stage, with resistance to standard therapies. Vitamin E-derived tocotrienols (TTs) possess a significant antitumour activity. Here, we evaluated the anti-cancer properties of δ-TT in CRPC cells (PC3 and DU145) and the related mechanisms of action.
MATERIALS AND METHODS:
MTT, Trypan blue and colony formation assays were used to assess cell viability/cell death/cytotoxicity. Western blot, immunofluorescence and MTT analyses were utilized to investigate apoptosis, ER stress and autophagy. Morphological changes were investigated by light and transmission electron microscopy.
RESULTS:
We demonstrated that δ-TT exerts a cytotoxic/proapoptotic activity in CRPC cells. We found that in PC3 cells: (a) δ-TT triggers both the endoplasmic reticulum (ER) stress and autophagy pathways; (b) autophagy induction is related to the ER stress, and this ER stress/autophagy axis is involved in the antitumour activity of δ-TT; in autophagy-defective DU145 cells, only the ER stress pathway is involved in the proapoptotic effects of δ-TT; (c) in both CRPC cell lines, δ-TT also induces an intense vacuolation prevented by the ER stress inhibitor salubrinal and the protein synthesis inhibitor cycloheximide, together with increased levels of phosphorylated JNK and p38, supporting the induction of paraptosis by δ-TT.
CONCLUSIONS:
These data demonstrate that apoptosis, involving ER stress and autophagy (in autophagy positive PC3 cells), and paraptosis are involved in the anti-cancer activity of δ-TT in CRPC cells.
Molecular Mechanisms of Action of Tocotrienols in Cancer: Recent Trends and Advancements
Aggarwal V, Kashyap D, Sak K, Tuli HS, Jain A, Chaudhary A, Garg VK, Sethi G, Yerer MB
Int J Mol Sci. 2019 Feb 2;20(3). pii: E656. doi: 10.3390/ijms20030656.
Abstract
Tocotrienols, found in several natural sources such as rice bran, annatto seeds, and palm oil have been reported to exert various beneficial health promoting properties especially against chronic diseases, including cancer. The incidence of cancer is rapidly increasing around the world not only because of continual aging and growth in global population, but also due to the adaptation of Western lifestyle behaviours, including intake of high fat diets and low physical activity. Tocotrienols can suppress the growth of different malignancies, including those of breast, lung, ovary, prostate, liver, brain, colon, myeloma, and pancreas. These findings, together with the reported safety profile of tocotrienols in healthy human volunteers, encourage further studies on the potential application of these compounds in cancer prevention and treatment. In the current article, detailed information about the potential molecular mechanisms of actions of tocotrienols in different cancer models has been presented and the possible effects of these vitamin E analogues on various important cancer hallmarks, i.e., cellular proliferation, apoptosis, angiogenesis, metastasis, and inflammation have been briefly analyzed.
Posttraumatic stress disorder-type behaviors in streptozotocin-induced diabetic rats can be prevented by prolonged treatment with vitamin E
de Souza CP, Gambeta E, Stern CAJ, Zanoveli JM
Behav Brain Res. 2019 Feb 1;359:749-754. doi: 10.1016/j.bbr.2018.09.008. Epub 2018 Sep 13
Abstract
Anxiety and stress disorders, such as posttraumatic stress disorder (PTSD) have been described as debilitating comorbidities of diabetes. In the present study, we aimed to investigate anxiety-like behavior and the extinction and generalization of aversive memories in fear conditioning using a streptozotocin-induced model of diabetes (DBT). Moreover, considering that DBT animals present increased oxidative stress in brain areas related to anxiety and memory, we aimed to evaluate the effect of prolonged treatment with antioxidant vitamin E on behavioral parameters of anxiety and fear memory and on the diabetic condition. It was observed that DBT animals showed a deficiency in extinguishing the aversive memory in a fear conditioning test, along with a generalization of the fear memory. They also present a more pronounced anxiety-like behavior in the elevated plus maze test. VIT E treatment (300 mg/kg, p.o.) was not able to reduce hyperglycemia; however, it was able to block the anxiogenic-like behavior, also improving the deficit in the extinction of the aversive memory as well as blocking the generalization of such memory in a different context. Taken together, our data suggest that DBT animals are prone to extinction deficits and generalization of fear memories, behaviors which are observed in models of PTSD. Lastly, prolonged VIT E supplementation may be effective in the treatment of anxiety, extinction deficit and generalization of fear memories induced by the diabetic condition.
Molecular Understanding of the Cardiomodulation in Myocardial Infarction and the Mechanism of Vitamin E Protection
Zarkasi KA, Jen-Kit T, Jubri Z
Trop Anim Health Prod. 2019 Jan 31. doi: 10.1007/s11250-019-01826-0. [Epub ahead of print]
Abstract
Myocardial infarction is a major cause of deaths globally. Modulation of several molecular mechanisms occur during the initial stages of myocardial ischemia prior to permanent cardiac tissue damage, which involve both pathogenic as well as survival pathways in the cardiomyocyte. Currently, there are increasing evidence regarding the cardioprotective role of vitamin E in alleviating the disease. This fat-soluble vitamin does not only act as a powerful antioxidant; it also has the ability to regulate several intracellular signalling pathways including HIF-1, PPAR-γ, Nrf-2, and NF-κB that influence the expression of a number of genes and their protein products. Essentially, it inhibits the molecular progression of tissue damage and preserves myocardial tissue viability. This review aims to summarize the molecular understanding of the cardiomodulation in myocardial infarction as well as the mechanism of vitamin E protection.
A Nested Case-Control Study on Plasma Vitamin E and Risk of Cancer: Evidence of Effect Modification by Selenium.
Wang J, Guo H, Lin T, Song Y, Zhang H, Wang B, Zhang Y, Li J, Huo Y, Wang X, Qin X, Xu X.
J Acad Nutr Diet. 2019 Jan 31. pii: S2212-2672(18)30852-9. doi: 10.1016/j.jand.2018.11.017. [Epub ahead of print]
Abstract
BACKGROUND:
Evidence from epidemiologic studies has been inconsistent regarding the role of vitamin E in cancer incidence risk.
OBJECTIVE:
The aim of this study was to evaluate the prospective association between baseline plasma vitamin E levels and subsequent cancer risk in Chinese adults with hypertension, and to identify effect modifiers.
DESIGN:
A nested, case-control study was conducted from 20,702 hypertensive participants in the China Stroke Primary Prevention Trial, a randomized, double-blind, controlled trial, conducted from May 2008 to August 2013.
PARTICIPANTS:
The current study included 229 new cancer cases and 229 controls matched for age (±1 year), sex, treatment group, and study site.
MAIN OUTCOME MEASURES:
Plasma vitamin E was measured by liquid chromatography with tandem quadrupole mass spectrometers and plasma selenium was measured by inductively coupled plasma mass spectrometry using Thermo Fisher iCAP Q ICP-MS.
STATISTICAL ANALYSES:
Odds ratios (OR) of cancer in relation to plasma concentrations of vitamin E were calculated using conditional logistic regression models.
RESULTS:
Median follow-up duration was 4.5 years. Overall, vitamin E was not associated with subsequent risk of total cancer (per 1-mg/L [2.3 μmol/L] increase: OR 1.01, 95% CI 0.93 to 1.09) and non-gastrointestinal cancer (OR 1.10, 95% CI 0.98 to 1.24). However, there was a significant, inverse association between vitamin E and gastrointestinal cancer (OR 0.86, 95% CI 0.75 to 0.99), particularly esophageal cancer (OR 0.67, 95% CI 0.48 to 0.95). Moreover, high vitamin E decreased the risk of total cancer (OR 0.91, 95% CI 0.84 to 0.99) and gastrointestinal cancer (OR 0.83, 95% CI 0.73 to 0.95) among patients with high selenium levels (median≥83.7 μg/L [1.1 μmol/L]), and increased the risk of total cancer (OR 1.13, 95% CI 1.00 to 1.26) and non-gastrointestinal cancer (OR 1.25, 95% CI 1.03 to 1.50) among those with low selenium levels (<83.7 μg/L [1.1 μmol/L]).
CONCLUSIONS:
This study suggests that higher levels of plasma vitamin E are associated with reduced risk of gastrointestinal cancer. High vitamin E decreased the risk of total cancer among patients with high selenium levels, but increased the risk of total cancer among those with low selenium levels.
Immune boosting role of vitamin E against pulmonary tuberculosis
Hussain MI, Ahmed W, Nasir M, Mushtaq MH, Sheikh AA, Shaheen AY, Mahmood A
Pak J Pharm Sci. 2019 Jan;32(1(Supplementary)):269-276.
Abstract
Tuberculosis is one of the leading causes of mortality in Pakistan which is linked with malnutrition and weak immunity. Such people are more prone to chronic infections including TB. The current study aimed to assess the effect of supplementation of Vitamin E on the immune status of human subjects against pulmonary tuberculosis. A total of 80 patients with pulmonary TB were divided into treatment group (vitamin E) and control group (Anti-tuberculosis regime). Presence of acid fast bacilli in sputum sample, Erythrocyte sedimentation rate, total leucocytes counts, body mass index and mid arm muscle circumference (MAMC) were recorded as per standard protocol. Levels of vitamin E, IgG, IgM and T-Cell count were determined before and after treatment. The results showed that 16% males and 33% females were underweight who consumed 1145 kcal energy instead of 2270 kcal per day and 19.5 gram protein instead of 78.6 grams. A non significant effect of vitamin Eon ESR and TLC values was observed but significant increase in level of immunoglobulins (IgG, IgM) and T-cell types (CD4+ and CD8+) was observed in patients as compared to control group. Results indicate that vitamin E plays important role in enhancing immunity of patients against TB.
Effects of antibiotics on degradation and bioavailability of different vitamin E forms in mice
Ran L, Liu AB, Lee MJ, Xie P, Lin Y, Yang CS
Biofactors. 2019 Jan 29. doi: 10.1002/biof.1492. [Epub ahead of print]
Abstract
Tocopherols (T) and tocotrienols (T3), all existing in α, β, γ, and δ-forms, are the eight forms of vitamin E (VE). In this study, we investigated the effects of gut microbiota on the degradation and tissue levels of different VE forms by treating mice with antibiotics in drinking water for 12 days. The mice also received an intragastric (i.g.) dose of VE mixture (mVE; α-T, γ-T, δ-T, γ-T3, and δ-T3, each at a dose of 75 mg/kg) every morning. Antibiotic treatment significantly increased the blood levels of all VE forms in mice that received an i.g. dose of mVE in the morning, 3 h before sacrifice. Without this morning dose, the blood levels of α-T were at the normal physiological levels, but those of the other VE forms were much lower; and the levels of all VE forms were not significantly affected by antibiotics. The liver levels of these VE forms were generally higher and followed the same pattern as the serum. On the contrary, the levels of most side-chain degradation metabolites of VE forms in the serum, liver, kidney, urine, and fecal samples were significantly decreased by antibiotics. The increased bioavailability of VE by antibiotics is probably due to increased absorption of VE or its decreased degradation by gut microbes. The results demonstrate the important roles of gut microbiota in the degradation of VE and in decreasing the bioavailabilities of VE forms.