The effect of vitamin E supplementation on biomarkers of endothelial function and inflammation among hemodialysis patients: A double-blinded randomized clinical trial

Pirhadi-Tavandashti N, Imani H, Ebrahimpour-Koujan S, Samavat S, Hakemi MS

Complement Ther Med. 2020 Mar;49:102357. doi: 10.1016/j.ctim.2020.102357. Epub 2020 Feb 26.

Abstract

OBJECTIVES:

The present study was aimed to investigate the effect of alpha-tocopherol supplementation on biomarkers of endothelial function (Intercellular Adhesion Molecule 1 and Vascular Cell Adhesion Protein 1) and inflammatory markers (Interleukin 6 and high-sensitivity C-reactive protein) among the hemodialysis patients.

METHODS:

To conduct this randomized, double-blinded, and placebo-controlled clinical trial, 49 hemodialysis patients, aged 20-60 years, were recruited and randomly divided into the intervention and control groups. The intervention group (n = 25) received 600 IU alpha-tocopherol soft gels (200 IU three times daily), while the controls (n = 24) consumed the identical placebo soft gels for 10 weeks. At the baseline and end of the study, 7 ml pre-dialysis blood samples were taken from all participants to measure their serum concentrations of ICAM-1, VCAM-1, IL-6, and hs-CRP.

RESULTS:

Alpha-tocopherol supplementation reduced the serum levels of ICAM-1 and VCAM-1 significantly (-140.67 ± 57.25 ng/ml vs. -15.97 ± 79.19 ng/ml, P = 0.001 for ICAM-1 and –6.79 ± 4.76 ng/ml vs. 1.02 ± 3.22 ng/ml, P = 0.019 for VCAM-1). However, no significant difference was observed between the two groups regarding the serum levels of hs-CRP (-0.15 ± 0.19 mg/l vs. 0.02 ± 0.12 mg/l; P = 0.32) and IL-6 (-0.03 ± 0.1 pg/ml vs. – 0.06 ± 0.11 pg/ml; P = 0.65).

CONCLUSIONS:

Our results showed that 10 weeks of supplementation with 600 IU alpha-tocopherol improved ICAM-1 and VCAM-1 levels, but did not have any effect on the serum concentration of IL-6 and hs-CRP in hemodialysis patients. Further studies are required to confirm these findings.

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Retinol and α-tocopherol in pregnancy: Establishment of reference intervals and associations with CBC

Liu J, Zhan S, Jia Y, Li Y, Liu Y, Dong Y, Tang G, Li L, Zhai Y, Cao Z

Matern Child Nutr. 2020 Mar 5:e12975. doi: 10.1111/mcn.12975. [Epub ahead of print]

Abstract

Profound physiological changes during pregnancy may affect the requirement of retinol and tocopherol, which are essential micronutrients for the maintenance of maternal health and foetal development. However, the current reference intervals (RIs) of retinol and tocopherol are based on non-pregnant population. In the present study, a liquid chromatography-tandem mass spectrometry quantitation method for serum retinol and α-tocopherol was established and validated. In addition, we established trimester-specific RIs of retinol and α-tocopherol using the data from paired screening test for 31,301 outpatients who participated in the prenatal vitamins A/E evaluation program at our hospital using the Hoffmann method, which is a simple indirect RI estimation method that does not require the recruitment of healthy subjects. Further, to explore the associations between the levels of retinol and α-tocopherol and the parameters of complete blood count (CBC), the results of retinol, α-tocopherol, and CBC of 1,977 pregnant outpatients in the third trimester were analysed. The testing interval between the levels of vitamins and CBC was no more than 7 days. Although no significant changes were noticed in the levels of retinol, the α-tocopherol levels continuously increased with normal physiological changes throughout pregnancy. Lower retinol levels were associated with the higher incidence of anaemia, whereas higher levels of retinol and lower levels of α-tocopherol were associated with higher platelet count.

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Differential Effects of MitoVitE, α-Tocopherol and Trolox on Oxidative Stress, Mitochondrial Function and Inflammatory Signalling Pathways in Endothelial Cells Cultured under Conditions Mimicking Sepsis

Minter BE, Lowes DA, Webster NR, Galley HF

Antioxidants (Basel). 2020 Feb 26;9(3). pii: E195. doi: 10.3390/antiox9030195.

Abstract

Sepsis is a life-threatening response to infection associated with inflammation, oxidative stress and mitochondrial dysfunction. We investigated differential effects of three forms of vitamin E, which accumulate in different cellular compartments, on oxidative stress, mitochondrial function, mRNA and protein expression profiles associated with the human Toll-like receptor (TLR) -2 and -4 pathways. Human endothelial cells were exposed to lipopolysaccharide (LPS)/peptidoglycan G (PepG) to mimic sepsis, MitoVitE, α-tocopherol, or Trolox. Oxidative stress, mitochondrial function, mitochondrial membrane potential and metabolic activity were measured. NFκB-P65, total and phosphorylated inhibitor of NFκB alpha (NFκBIA), and STAT-3 in nuclear extracts, interleukin (IL)-6 and IL-8 production in culture supernatants and cellular mRNA expression of 32 genes involved in Toll-like receptor-2 and -4 pathways were measured. Exposure to LPS/PepG caused increased total radical production (p = 0.022), decreased glutathione ratio (p = 0.016), reduced membrane potential and metabolic activity (both p < 0.0001), increased nuclear NFκB-P65 expression (p = 0.016) and increased IL-6/8 secretion (both p < 0.0001). MitoVitE, α- tocopherol and Trolox were similar in reducing oxidative stress, NFκB activation and interleukin secretion. MitoVitE had widespread downregulatory effects on gene expression. Despite differences in site of actions, all forms of vitamin E were protective under conditions mimicking sepsis. These results challenge the concept that protection inside mitochondria provides better protection.

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MPOB exploring palm oil-based MCT as anti-viral agent to combat coronavirus

The Malaysian Palm Oil Board (MPOB) is exploring palm oil-based medium-chain triglycerides (MCT) as an anti-viral property, with the aim to boost the immune system to protect from the 2019 novel coronavirus (2019-nCoV) attack, director-general Dr Ahmad Parveez Ghulam Kadir said.

According to Ahmad Parveez, there were some Chinese experts who had engaged with MPOB to seek collaborative study related to palm tocotrienols’ possible effect on human immunity, which is now being widely discussed to prevent the coronavirus infection.

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Tocotrienol-rich vitamin E improves diabetic nephropathy and persists 6-9 months after washout: a phase IIa randomized controlled trial

Tan GCJ, Tan SMQ, Phang SCW, Ng YT, Ng EY, Ahmad B, Palamisamy UDM, Kadir KA

Ther Adv Endocrinol Metab. 2019 Dec 25;10:2042018819895462. doi: 10.1177/2042018819895462. eCollection 2019.

Abstract

Chronic hyperglycemia in type 2 diabetes mellitus increases oxidative stress and inflammation which contributes to long-term diabetic kidney disease. Tocotrienol-rich vitamin E, as Tocovid, has been shown to reduce oxidative stress and inflammation to ameliorate diabetes in rat models and human subjects. In this prospective, multicenter, double-blinded, placebo-controlled clinical trial, 54 patients (duration = 18.4 years, HbA1c = 8.8%) with diabetic nephropathy were randomized to receive Tocovid 200 mg or placebo for 12 weeks. Fasting blood samples were taken to measure HbA1c, serum creatinine, estimate glomerular filtration rate (eGFR), urine albumin:creatinine ratio, malondialdehyde, tumor necrosis factor receptor-1, vascular cell adhesion molecule-1 (VCAM-1), and thromboxane-B2. Patients were reassessed 6-9 months post-washout. After 12 weeks of supplementation, Tocovid significantly decreased serum creatinine levels (mean difference: -3.3 ± 12.6 versus 5.4 ± 14.2, p = 0.027) and significantly increase eGFR (mean difference: 1.5 ± 7.6 versus -2.9 ± 8.0, p = 0.045) compared with placebo. There were no significant changes in HbA1c, blood pressure, and other parameters. Subgroup analysis revealed that in patients with low serum vitamin E concentrations at baseline, Tocovid reduced serum creatinine, eGFR, and VCAM-1 significantly. After 6-9 months of washout, persistent difference in serum creatinine remained between groups (mean difference: 0.82 ± 8.33 versus 11.26 ± 15.47, p = 0.031), but not eGFR. Tocovid at 400 mg/day significantly improved renal function in 12 weeks of supplementation, as assessed by serum creatinine and eGFR, which remained significant 6-9 months post-washout.

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Effects of tocotrienol supplementation in Friedreich’s ataxia: A model of oxidative stress pathology

Bolotta A, Pini A, Abruzzo PM, Ghezzo A, Modesti A, Gamberi T, Ferreri C, Bugamelli F, Fortuna F, Vertuani S, Manfredini S, Zucchini C, Marini M

Exp Biol Med (Maywood). 2019 Dec 3:1535370219890873. doi: 10.1177/1535370219890873.

Abstract Friedreich’s ataxia is an autosomal recessive disorder characterized by impaired mitochondrial function, resulting in oxidative stress. In this study, we aimed at evaluating whether tocotrienol, a phytonutrient that diffuses easily in tissues with saturated fatty layers, could complement the current treatment with idebenone, a quinone analogue with antioxidant properties. Five young Friedreich’s ataxia patients received a low-dose tocotrienol supplementation (5 mg/kg/day), while not discontinuing idebenone treatment. Several oxidative stress markers and biological parameters related to oxidative stress were evaluated at the time of initiation of treatment and 2 and 12 months post-treatment. Some oxidative stressrelated parameters and some inflammation indices were altered in Friedreich’s ataxia patients taking idebenone alone and tended to be normal values following tocotrienol supplementation; likewise, a cardiac magnetic resonance study showed some improvement following one-year tocotrienol treatment. The pathway by which tocotrienol affects the Nrf2 modulation of hepcidin gene expression, a peptide involved in iron handling and in inflammatory responses, is viewed in the light of the disruption of the iron intracellular distribution and of the Nrf2 anergy characterizing Friedreich’s ataxia. This research provides a suitable model to analyze the efficacy of therapeutic strategies able to counteract the excess free radicals in Friedreich’s ataxia, and paves the way to long-term clinical studies.

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Plasma versus Erythrocyte Vitamin E in Renal Transplant Recipients, and Duality of Tocopherol Species

Sotomayor CG, Rodrigo R, Gomes-Neto AW, Gormaz JG, Pol RA, Minović I, Eggersdorfer ML, Vos M, Riphagen IJ, de Borst MH, Nolte IM, Berger SP, Navis GJ, Bakker SJL

Nutrients. 2019 Nov 19;11(11). pii: E2821. doi: 10.3390/nu11112821.

Abstract

Redox imbalance is an adverse on-going phenomenon in renal transplant recipients (RTR). Vitamin E has important antioxidant properties that counterbalance its deleterious effects. However, plasma vitamin E affinity with lipids challenges interpretation of its levels. To test the hypothesis that erythrocyte membranes represent a lipids-independent specimen to estimate vitamin E status, we performed a cross-sectional study in a cohort of adult RTR (n = 113) recruited in a university setting (2015-2018). We compared crude and total lipids-standardized linear regression-derived coefficients of plasma and erythrocyte tocopherol species in relation to clinical and laboratory parameters. Strongly positive associations of fasting lipids with plasma tocopherol became inverse, rather than absent, in total lipids-standardized analyses, indicating potential overadjustment. Whilst, no variables from the lipids domain were associated with the tocopherol species measured from erythrocyte specimens. In relation to inflammatory status and clinical parameters with antioxidant activity, we found associations in directions that are consistent with either beneficial or adverse effects concerning α- or γ-tocopherol, respectively. In conclusion, erythrocytes offer a lipids-independent alternative to estimate vitamin E status and investigate its relationship with parameters over other biological domains. In RTR, α- and γ-tocopherol may serve as biomarkers of relatively lower or higher vulnerability to oxidative stress and inflammation, noticeably in opposite directions.

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Vitamin e-loaded membrane dialyzers reduce hemodialysis inflammaging

Sepe V, Gregorini M, Rampino T, Esposito P, Coppo R, Galli F, Libetta C

BMC Nephrol. 2019 Nov 15;20(1):412. doi: 10.1186/s12882-019-1585-6.

Abstract

BACKGROUND:

Inflammaging is a persistent, low-grade, sterile, nonresolving inflammatory state, associated with the senescence of the immune system. Such condition downregulates both innate and adaptive immune responses during chronic disorders as type II diabetes, cancer and hemodialysis, accounting for their susceptibility to infections, malignancy and resistance to vaccination. Aim of this study was to investigate hemodialysis inflammaging, by evaluating changes of several hemodialysis treatments on indoleamine 2,3-dioxygenase-1 activity and nitric oxide formation.

METHODS:

We conducted a randomized controlled observational crossover trial. Eighteen hemodialysis patients were treated with 3 different hemodialysis procedures respectively: 1) Low-flux bicarbonate hemodialysis, 2) Low-flux bicarbonate hemodialysis with vitamin E - loaded dialyzers, and 3) Hemodialfitration. The control group consisted of 14 hospital staff healthy volunteers. Blood samples were collected from all 18 hemodialysis patients just after the long interdialytic interval, at the end of each hemodialysis treatment period.

RESULTS:

Hemodialysis kynurenine and kynurenine/L - tryptophan blood ratio levels were significantly higher, when compared to the control group, indicating an increased indoleamine 2,3-dioxygenase-1 activity in hemodialysis patients. At the end of the low-flux bicarbonate hemodialysis with vitamin E - loaded dialyzers period, L - tryptophan serum levels remained unchanged vs both low-flux bicarbonate hemodialysis and hemodialfitration. Kynurenine levels instead decreased, resulting in a significant reduction of kynurenine/L - tryptophan blood ratio and indoleamine 2,3-dioxygenase-1 activity, when matched to both low-flux bicarbonate hemodialysis and HDF respectively. Serum nitric oxide control group levels, were significantly lower when compared to all hemodialysis patient groups. Interestingly, low-flux bicarbonate hemodialysis with vitamin E - loaded dialyzers nitric oxide serum levels from venous line blood samples taken 60 min after starting the hemodialysis session were significantly lower vs serum taken simultaneously from the arterial blood line.

CONCLUSIONS:

The treatment with more biocompatible hemodialysis procedure as low-flux bicarbonate hemodialysis with vitamin E - loaded dialyzers, reduced indoleamine 2,3-dioxygenase-1 activity and nitric oxide formation when compared to both low-flux bicarbonate hemodialysis and hemodialfitration. These data suggest that low-flux bicarbonate hemodialysis with vitamin E - loaded dialyzers lowering hemodialysis inflammaging, could be associated to changes of proinflammatory signalling a regulated molecular level.

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Investigation of the curative effects of palm vitamin E tocotrienols on autoimmune arthritis disease in vivo

Zainal Z, Rahim AA, Radhakrishnan AK, Chang SK, Khaza'ai H

Sci Rep. 2019 Nov 14;9(1):16793. doi: 10.1038/s41598-019-53424-7.

Abstract

The tocotrienol-rich fraction (TRF) from palm oil contains vitamin E, which possesses potent antioxidant and anti-inflammatory activities. Rheumatoid arthritis (RA) is a chronic joint inflammatory disease characterised by severe joint pain, cartilage destruction, and bone erosion owing to the effects of various pro-inflammatory mediators and cytokines. Here, we investigated the therapeutic effects of TRF in a rat model of collagen-induced arthritis (CIA). Arthritis was induced by a single intradermal injection of collagen type II in Dark Agouti (DA) rats. Rats were then treated with or without TRF by oral gavage from day 28 after the first collagen injection. Arthritic rats supplemented with TRF showed decreased articular index scores, ankle circumferences, paw volumes, and radiographic scores when compared with untreated rats. The untreated arthritic rats showed higher plasma C-reactive protein levels (p < 0.05) and production of pro-inflammatory cytokines than arthritic rats fed TRF. Moreover, there was a marked reduction in the severity of histopathological changes observed in arthritic rats treated with TRF compared with that in untreated arthritic rats. Overall, the results show that TRF had beneficial effects in this rat model of RA.

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Therapeutic effect of Vitamin E in preventing bone loss: An evidence-based review

Nazrun Shuid A, Das S, Mohamed IN

Int J Vitam Nutr Res. 2019 Nov;89(5-6):357-370. doi: 10.1024/0300-9831/a000566.

Abstract

The present review explored the anti-inflammatory and immunomodulatory properties of vitamin E, which has protective action against osteoporosis. A systematic review of the literature was conducted to identify the published bone studies on vitamin E. The studies included inflammatory or immunology-related parameters. Medline and Scopus databases were searched for relevant studies published from 2005 till 2015. Research articles published in English and confined to the effect of vitamin E on bone were included. It is pertinent to mention that these studies took into consideration inflammatory or immunology parameters including interleukin (IL)-1, IL-6, receptor activator of nuclear factor kappa-B ligand (RANKL), inducible nitric oxide synthases (iNOS), serum amyloid A (SAA), e-selection and high-sensitivity C-reactive protein (hs-CRP). An extended literature search yielded 127 potentially relevant articles with seven articles meeting the inclusion and exclusion criteria. Another recent article was added with the total number accounting to eight. All these included literature comprised five animal studies, one in-vitro study and two human studies. These studies demonstrated that vitamin E, especially tocotrienol, was able to alleviate IL-1, IL-6, RANKL, iNOS and hs-CRP levels in relation to bone metabolism. In conclusion, vitamin E exerts its anti-osteoporotic actions via its anti-inflammatory and immunomodulatory effects.

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