Background
People with cystic fibrosis are at an increased risk of fat‐soluble vitamin deficiency including vitamin E. Vitamin E deficiency can cause a host of conditions such as haemolytic anaemia, ...cerebellar ataxia and cognitive difficulties. Vitamin E supplementation is widely recommended in cystic fibrosis and aims to ameliorate this deficiency. This is an updated version of the review.
Objectives
To determine the effects of any level of vitamin E supplementation on the frequency of vitamin E deficiency disorders in people with cystic fibrosis.
Search methods
We searched the Cochrane Group's Cystic Fibrosis Trials Register and also searched international trial registers for any ongoing clinical trials that were not identified during our register search.
Date of last search of the Register: 10 October 2016.
Date of last search of international trial registers: 15 February 2017.
Selection criteria
Randomised controlled trials and quasi‐randomised controlled trials comparing any preparation of vitamin E supplementation to placebo or no supplement, regardless of dosage or duration.
Data collection and analysis
Two authors extracted outcome data from each study (published information) and assessed the risk of bias of each included study.
Main results
Four studies with a total of 141 participants were included in the review, two of these were in children (aged six months to 14.5 years), and the other two did not specify participants’ age. All studies used different formulations and doses of vitamin E for various durations of treatment (10 days to six months). Two studies compared the supplementation of fat‐soluble as well as water‐soluble formulations to no supplementation in different arms of the same study. A third study compared a water‐soluble formulation to a placebo; and in the fourth study a fat‐soluble formulation of vitamin E was assessed against placebo.
At one month, three months and six months, water‐soluble vitamin E significantly improved serum vitamin E levels compared with control: at one month, two studies, mean difference 17.66 (95% confidence interval 10.59 to 24.74); at three months, one study, mean difference 11.61 (95% confidence interval 4.77 to 18.45); and at six months, one study, mean difference 19.74 (95% confidence interval 13.48 to 26.00). At one month fat‐soluble vitamin E significantly improved serum vitamin E levels compared with control: one month, two studies, mean difference 13.59 (95% CI 9.52 to 17.66). The findings at three months were imprecise; one study; mean difference 6.40 (95% confidence interval ‐1.45 to 14.25).
None of the studies report the review's primary outcomes of vitamin E total lipid ratio or the incidence of vitamin E‐specific deficiency disorders, or the secondary outcomes lung function or quality of life. Only one study, comparing water‐soluble vitamin E with placebo, reported the secondary outcome of growth and nutritional status (weight), but the results are uncertain due to imprecision around the effect estimate.
There was limited detail about randomisation and blinding in the included studies which compromises the quality of the evidence base for the review. The heterogeneous mix of the formulations with differing biovailabilities among these studies also limits the generalisability of the data to the wider cystic fibrosis population.
Authors' conclusions
Vitamin E supplementation led to an improvement in vitamin E levels in people with cystic fibrosis, although the studies may have been at risk of bias. No data on other outcomes of interest were available to allow conclusions about any other benefits of this therapy.
In future, larger studies are needed, especially in people already being treated with enteric‐coated pancreatic enzymes and supplemented with vitamin E, to look at more specific outcome measures such as vitamin E status, lung function and nutritional status. Future studies could also look at the optimal dose of vitamin E required to achieve maximal clinical effectiveness.
Currently CRISPR/Cas9 is a widely used efficient tool for gene editing. Precise control over the CRISPR/Cas9 system with high temporal and spatial resolution is essential for studying gene regulation ...and editing. Here, we synthesized a novel light‐controlled crRNA by coupling vitamin E and a photolabile linker at the 5′ terminus to inactivate the CRISPR/Cas9 system. The vitamin E modification did not affect ribonucleoprotein (RNP) formation of Cas9/crRNA/tracrRNA complexes but did inhibit the association of RNP with the target DNA. Upon light irradiation, vitamin E‐caged crRNA was successfully activated to achieve light‐induced genome editing of vascular endothelial cell‐growth factor A (VEGFA) in human cells through a T7E1 assay and Sanger sequencing as well as gene knockdown of EGFP expression in EGFP stably expressing cells. This new caging strategy for crRNA could provide new methods for spatiotemporal photoregulation of CRISPR/Cas9‐mediated gene editing.
Caged crRNA was readily developed through a terminus modification with a photolabile linker and vitamin E for construction of a caged CRISPR/Cas9 system. The system was successfully used for photomodulation of VEGFA gene editing and control of EGFP gene silencing through the temporary inhibition of the interaction between the target DNA and Cas9/crRNA/tracrRNA complex.
Abstract The concept of mild chronic vascular inflammation as part of the pathophysiology of cardiovascular disease, most importantly hypertension and atherosclerosis, has been well accepted. Indeed ...there are links between vascular inflammation, endothelial dysfunction and oxidative stress. However, there are still gaps in our understanding regarding this matter that might be the cause behind disappointing results of antioxidant therapy for cardiovascular risk factors in large-scale long-term randomised controlled trials. Apart from the limitations of our knowledge, limitations in methodology and assessment of the body's endogenous and exogenous oxidant-antioxidant status are a serious handicap. The pleiotropic effects of antioxidant and anti-inflammation that are shown by some well-established antihypertensive agents and statins partly support the idea of using antioxidants in vascular diseases as still relevant. This review aims to provide an overview of the links between oxidative stress, vascular inflammation, endothelial dysfunction and cardiovascular risk factors, importantly focusing on blood pressure regulation and atherosclerosis. In view of the potential benefits of antioxidants, this review will also examine the proposed role of vitamin C, vitamin E and polyphenols in cardiovascular diseases as well as the success or failure of antioxidant therapy for cardiovascular diseases in clinical trials.
Resveratrol, Vitamin E (VE), and Epigallocatechin Gallate (EGCG) were formulated into lipid nanoparticles. Both resveratrol and VE lipid nanoparticles provided effective protection of actives against ...UV induced degradation. However, lipid nanoparticles did not show protection from UV degradation for EGCG in this work. An active release study exhibited a sustained release of resveratrol over 70% after 24h. Skin penetration studies showed that lipid nanoparticles directionally improved the penetration of resveratrol through the stratum corneum. Our findings suggest that lipid nanoparticles are promising viable carriers for the delivery of resveratrol and VE to provide long-lasting antioxidant benefits to the skin.
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Solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) have been studied as potential carriers for both dermal and transdermal drug delivery. SLN contain lipid droplets that are fully crystallized and have a highly-ordered crystalline structure. NLC are modified SLN in which the lipid phase contains both solid and liquid lipids at room temperature. SLN and NLC are thought to combine the advantages of polymeric particles, liposomes and emulsions. Therefore they provide high encapsulation percentages, better protection for incorporated actives and allow for control of desired release profile. In this work, Resveratrol, Vitamin E (VE), and Epigallocatechin Gallate (EGCG) all potent antioxidants known to provide protection to the skin, were formulated into lipid nanoparticles. Several different formulations were successfully developed and demonstrated high uniformity and stability. Both resveratrol and VE lipid nanoparticles provided effective protection of actives against UV induced degradation. However, lipid nanoparticles did not show protection from UV degradation for EGCG in this work. An active release study exhibited a sustained release of resveratrol over 70% after 24h. Skin penetration studies showed that lipid nanoparticles directionally improved the penetration of resveratrol through the stratum corneum. Our findings suggest that lipid nanoparticles are promising viable carriers for the delivery of resveratrol and VE to provide longlasting antioxidant benefits to the skin.
Background: Patients with chronic pancreatitis are at risk of malnutrition and nutrient deficiency due to malabsorption, pain, and poor diet. We sought to examine fat-soluble vitamin levels and ...malnutrition parameters in patients with chronic pancreatitis. Materials and Methods: In a prospective controlled cohort study, 128 subjects (62 chronic pancreatitis patients and 66 age-/sex-matched controls) were recruited. Body mass index (BMI), handgrip strength (measure of functional capacity), fat stores (triceps skin fold), muscle stores (mid-arm muscle circumference), exocrine function, and serum levels of fat-soluble vitamins (A, D, E) were measured. Results: Half of patients in the chronic pancreatitis group were overweight or obese, although the mean BMI was lower in patients than in controls (P = .007). Handgrip strength (P = .048), fat stores (P = .000), and muscle stores (P = .001) were lower in patients than in controls. Of the patients, 14.5% and 24.2% were deficient in vitamins A and E, respectively. Nineteen percent of patients had excess serum vitamin A levels. Conclusions: Despite the prevalence of overweight and obesity, patients had lower muscle stores, strength, and abnormal vitamin levels. Detailed nutrition assessment including anthropometry and vitamin status is warranted in chronic pancreatitis.
The initial report of the Selenium and Vitamin E Cancer Prevention Trial (SELECT) found no reduction in risk of prostate cancer with either selenium or vitamin E supplements but a statistically ...nonsignificant increase in prostate cancer risk with vitamin E. Longer follow-up and more prostate cancer events provide further insight into the relationship of vitamin E and prostate cancer.
To determine the long-term effect of vitamin E and selenium on risk of prostate cancer in relatively healthy men.
A total of 35,533 men from 427 study sites in the United States, Canada, and Puerto Rico were randomized between August 22, 2001, and June 24, 2004. Eligibility criteria included a prostate-specific antigen (PSA) of 4.0 ng/mL or less, a digital rectal examination not suspicious for prostate cancer, and age 50 years or older for black men and 55 years or older for all others. The primary analysis included 34,887 men who were randomly assigned to 1 of 4 treatment groups: 8752 to receive selenium; 8737, vitamin E; 8702, both agents, and 8696, placebo. Analysis reflect the final data collected by the study sites on their participants through July 5, 2011.
Oral selenium (200 μg/d from L-selenomethionine) with matched vitamin E placebo, vitamin E (400 IU/d of all rac-α-tocopheryl acetate) with matched selenium placebo, both agents, or both matched placebos for a planned follow-up of a minimum of 7 and maximum of 12 years.
Prostate cancer incidence.
This report includes 54,464 additional person-years of follow-up and 521 additional cases of prostate cancer since the primary report. Compared with the placebo (referent group) in which 529 men developed prostate cancer, 620 men in the vitamin E group developed prostate cancer (hazard ratio HR, 1.17; 99% CI, 1.004-1.36, P = .008); as did 575 in the selenium group (HR, 1.09; 99% CI, 0.93-1.27; P = .18), and 555 in the selenium plus vitamin E group (HR, 1.05; 99% CI, 0.89-1.22, P = .46). Compared with placebo, the absolute increase in risk of prostate cancer per 1000 person-years was 1.6 for vitamin E, 0.8 for selenium, and 0.4 for the combination.
Dietary supplementation with vitamin E significantly increased the risk of prostate cancer among healthy men.
Clinicaltrials.gov Identifier: NCT00006392.
Few studies have previously assessed how pre-existing vitamin E status is associated with risk of tuberculosis (TB) disease progression.
We evaluated the association between baseline plasma ...concentrations of 3 vitamin E isomers (α-tocopherol, γ-tocopherol, and δ-tocopherol) and TB disease risk.
We conducted a case-control study nested within a longitudinal cohort of household contacts (HHCs) of pulmonary TB cases in Lima, Peru. We defined cases as HHCs who developed active TB disease ≥15 d after the diagnosis of the index patient, and we matched each case to 4 control cases who did not develop active TB based on age by year and gender. We used univariate and multivariate conditional logistic regression to calculate ORs for incident TB disease by plasma concentrations of α-tocopherol, γ-tocopherol, and δ-tocopherol.
Among 6751 HIV-negative HHCs who provided baseline blood samples, 180 developed secondary TB during follow-up. After controlling for possible confounders, we found that baseline α-tocopherol deficiency conferred increased risk of incident TB disease (adjusted OR: 1.59; 95% CI: 1.02, 2.50; P = 0.04). Household contacts in the lowest tertile of δ-tocopherol were also at increased risk of progression to TB disease compared to those in the highest tertile (tertile 1 compared with tertile 3, adjusted OR: 2.29; 95% CI: 1.29, 4.09; P-trend = 0.005). We found no association between baseline concentration of γ-tocopherol and incident TB disease.
Vitamin E deficiency was associated with an increased risk of progression to TB disease among HHCs of index TB cases. Assessment of vitamin E status among individuals at high risk for TB disease may play a role in TB control efforts.
Delivery of a high concentration of anticancer drugs specifically to cancer cells remains the biggest challenge for the treatment of multidrug-resistant cancer. Poloxamers and D-α-Tocopheryl ...polyethylene glycol 1000 succinate (TPGS) are known inhibitors of P-glycoprotein (P-gp). Mixed micelles prepared from Poloxamer 407 and TPGS may increase the therapeutic efficacy of the drug by delivering high concentrations inside the cells and inhibiting P-gp. Gambogic acid (GA) is a naturally derived novel anticancer agent, but poor solubility and toxic side effects limit its use. In this study, we have developed Poloxamer 407 and TPGS mixed micelle-encapsulating GA for the treatment of breast and multidrug-resistant cancer.
GA-loaded Poloxamer 407/TPGS mixed micelles were prepared using a thin film hydration method, and their physicochemical properties were characterized. Cellular accumulation and cytotoxicity of the GA-loaded Poloxamer 407/TPGS mixed micelles were studied in breast cancer cells, MCF-7 cells, and multidrug-resistant NCI/ADR-RES cells.
The diameter of GA-loaded Poloxamer 407/TPGS mixed micelles was about 17.4 ± 0.5 nm and the zeta potential -13.57 mV. The entrapment efficiency of GA was 93.1% ± 0.5% and drug loading was about 9.38% ± 0.29%. Differential scanning calorimetry and X-ray powder diffraction studies confirmed that GA is encapsulated by the polymers. The in vitro release studies showed that mixed micelles sustained the release of GA for more than 4 days. Results from cellular uptake studies indicated that GA-loaded Poloxamer 407/TPGS mixed micelles had increased cellular uptake of GA in NCI/ADR-RES cells. Cytotoxicity of GA-loaded Poloxamer 407/TPGS mixed micelles was found to be 2.9 times higher in multidrug-resistant NCI/ADR-RES cells, and 1.6 times higher in MCF-7 cells, as compared with unencapsulated GA.
This study suggests that Poloxamer 407/TPGS mixed micelles can be used as a delivery system for GA to treat breast and multidrug-resistant cancer.
This review aims to highlight the development of novel vitamin E conjugates for the vectorization of active pharmaceutical ingredients through nanotechnologies. The physico-chemical and biological ...properties of vitamin E derivatives offer multiple advantages in drug delivery like biocompatibility, improvement of drug solubility and anticancer activity. Nanomedicines have shown high potential in drug delivery since (i) they may offer better drug biopharmaceutical properties such as longer half-life or better bioavailability and (ii) they have shown benefits in cancer therapy by improving anticancer drug therapeutic index. Vitamin E-based nanomedicines were developed to combine the pharmaceutical properties of both vitamin E and nanomedicines for two purposes: (i) to improve water solubility of hydrophobic drugs and (ii) to enhance the therapeutic efficiency of anticancer agents.
This review is divided into three parts: the first one describes the biology and the metabolic functions of vitamin E, the second one focuses on the anticancer activity of two vitamin E derivatives: vitamin E succinate (TOS) and vitamin E polyethylene glycol-succinate (TPGS). Finally, in the third part, we discuss vitamin E derivatives based-nanomedicines.
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Vitamin E and its anticancer effects Abraham, Annette; Kattoor, Ajoe John; Saldeen, Tom ...
Critical reviews in food science and nutrition,
09/2019, Letnik:
59, Številka:
17
Journal Article
Recenzirano
Vitamin E is a lipid soluble vitamin comprising of eight natural isoforms, namely, α, β, δ, γ isoforms of tocopherol and α, β, δ, γ isoforms of tocotrienol. Many studies have been performed to ...elucidate its role in cancer. Until last decade, major focus was on alpha tocopherol and its anticancer effects. However, major clinical trials using alpha-tocopherol like SELECT trial and ATBC trial did not yield meaningful results. Hence there was a shift of focus to gamma-tocopherol, delta-tocopherol and tocotrienol. Unlike alpha-tocopherol, gamma-tocopherol and delta-tocopherol can scavenge reactive nitrogen species in addition to reactive oxygen species. Antiangiogenic effect, inhibition of HMG CoA reductase enzyme and inhibition of NF-κB pathway make the anti-cancer effects of tocotrienols unique compared to other vitamin E isoforms. Preclinical research on non-alpha tocopherol isoforms of vitamin E showed promising data on their anticancer effects. In this review, we deal with the current understanding on the potential mechanisms involved in the anticancer effects of vitamin E and the controversies in this field over last three decades. We also highlight the need to conduct further research on the anticancer effects of non-alpha-tocopherol isoforms in larger population and clinical setting.
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