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Nutrients Jan 2022This review summarizes the current knowledge on essential vitamins B, B, B, and B. These B-complex vitamins must be taken from diet, with the exception of vitamin B,... (Review)
Review
This review summarizes the current knowledge on essential vitamins B, B, B, and B. These B-complex vitamins must be taken from diet, with the exception of vitamin B, that can also be synthetized from amino acid tryptophan. All of these vitamins are water soluble, which determines their main properties, namely: they are partly lost when food is washed or boiled since they migrate to the water; the requirement of membrane transporters for their permeation into the cells; and their safety since any excess is rapidly eliminated via the kidney. The therapeutic use of B-complex vitamins is mostly limited to hypovitaminoses or similar conditions, but, as they are generally very safe, they have also been examined in other pathological conditions. Nicotinic acid, a form of vitamin B, is the only exception because it is a known hypolipidemic agent in gram doses. The article also sums up: (i) the current methods for detection of the vitamins of the B-complex in biological fluids; (ii) the food and other sources of these vitamins including the effect of common processing and storage methods on their content; and (iii) their physiological function.
Topics: Avitaminosis; Humans; Thiamine; Vitamin A; Vitamin B Complex; Vitamin K
PubMed: 35276844
DOI: 10.3390/nu14030484 -
Circulation May 2022Menaquinone-7 (MK-7), also known as vitamin K2, is a cofactor for the carboxylation of proteins involved in the inhibition of arterial calcification and has been... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Menaquinone-7 (MK-7), also known as vitamin K2, is a cofactor for the carboxylation of proteins involved in the inhibition of arterial calcification and has been suggested to reduce the progression rate of aortic valve calcification (AVC) in patients with aortic stenosis.
METHODS
In a randomized, double-blind, multicenter trial, men from the community with an AVC score >300 arbitrary units (AU) on cardiac noncontrast computer tomography were randomized to daily treatment with tablet 720 µg MK-7 plus 25 µg vitamin D or matching placebo for 24 months. The primary outcome was the change in AVC score. Selected secondary outcomes included change in aortic valve area and peak aortic jet velocity on echocardiography, heart valve surgery, change in aortic and coronary artery calcification, and change in dp-ucMGP (dephosphorylated-undercarboxylated matrix Gla-protein). Safety outcomes included all-cause death and cardiovascular events.
RESULTS
From February 1, 2018, to March 21, 2019, 365 men were randomized. Mean age was 71.0 (±4.4) years. The mean (95% CI) increase in AVC score was 275 AU (95% CI, 225-326 AU) and 292 AU (95% CI, 246-338 AU) in the intervention and placebo groups, respectively. The mean difference on AVC progression was 17 AU (95% CI, -86 to 53 AU; =0.64). The mean change in aortic valve area was 0.02 cm (95% CI, -0.09 to 0.12 cm; =0.78) and in peak aortic jet velocity was 0.04 m/s (95% CI, -0.11 to 0.02 m/s; =0.21). The progression in aortic and coronary artery calcification score was not significantly different between patients treated with MK-7 plus vitamin D and patients receiving placebo. There was no difference in the rate of heart valve surgery (1 versus 2 patients; =0.99), all-cause death (1 versus 4 patients; =0.37), or cardiovascular events (10 versus 10 patients; =0.99). Compared with patients in the placebo arm, a significant reduction in dp-ucMGP was observed with MK-7 plus vitamin D (-212 pmol/L versus 45 pmol/L; <0.001).
CONCLUSIONS
In elderly men with an AVC score >300 AU, 2 years MK-7 plus vitamin D supplementation did not influence AVC progression.
REGISTRATION
URL: https://www.
CLINICALTRIALS
gov; Unique identifier: NCT03243890.
Topics: Aged; Aortic Valve; Aortic Valve Stenosis; Calcinosis; Female; Humans; Male; Vitamin D; Vitamin K 2
PubMed: 35465686
DOI: 10.1161/CIRCULATIONAHA.121.057008 -
Cell Reports May 2023Vitamin K is a micronutrient necessary for γ-carboxylation of glutamic acids. This post-translational modification occurs in the endoplasmic reticulum (ER) and affects...
Vitamin K is a micronutrient necessary for γ-carboxylation of glutamic acids. This post-translational modification occurs in the endoplasmic reticulum (ER) and affects secreted proteins. Recent clinical studies implicate vitamin K in the pathophysiology of diabetes, but the underlying molecular mechanism remains unknown. Here, we show that mouse β cells lacking γ-carboxylation fail to adapt their insulin secretion in the context of age-related insulin resistance or diet-induced β cell stress. In human islets, γ-carboxylase expression positively correlates with improved insulin secretion in response to glucose. We identify endoplasmic reticulum Gla protein (ERGP) as a γ-carboxylated ER-resident Ca-binding protein expressed in β cells. Mechanistically, γ-carboxylation of ERGP protects cells against Ca overfilling by diminishing STIM1 and Orai1 interaction and restraining store-operated Ca entry. These results reveal a critical role of vitamin K-dependent carboxylation in regulation of Ca flux in β cells and in their capacity to adapt to metabolic stress.
Topics: Mice; Animals; Humans; Vitamin K; Osteocalcin; Protein Processing, Post-Translational; Insulin; Stress, Physiological; Calcium
PubMed: 37171959
DOI: 10.1016/j.celrep.2023.112500 -
Advances in Nutrition (Bethesda, Md.) Feb 2022
Topics: Humans; Vitamin K
PubMed: 34971361
DOI: 10.1093/advances/nmab133 -
Food & Function Apr 2020Previous studies did not draw a consistent conclusion about the effects of vitamin K combined with vitamin D on human skeletal quality. (Meta-Analysis)
Meta-Analysis
BACKGROUND
Previous studies did not draw a consistent conclusion about the effects of vitamin K combined with vitamin D on human skeletal quality.
METHOD AND FINDINGS
A comprehensive search on Web of Science, PubMed, Embase and the Cochrane Library (from 1950 to February 2020) and bibliographies of relevant articles was undertaken, with the meta-analysis of eight randomized controlled trials (RCTs) including a total of 971 subjects. Vitamin K combined with vitamin D significantly increased the total bone mineral density (BMD): the pooled effect size was 0.316 [95% CI (confidence interval), 0.031 to 0.601]. A significant decrease in undercarboxylated osteocalcin (-0.945, -1.113 to -0.778) can be observed with the combination of vitamin K and D. Simultaneously, subgroup analysis showed that K2 or vitamin K (not specified) supplement was less than 500 μg d-1, which when combined with vitamin D can significantly increase the total BMD compared with the control group fed a normal diet or the group with no treatment (0.479, 0.101 to 0.858 and 0.570, 0.196 to 0.945).
CONCLUSIONS
The combination of vitamin K and D can significantly increase the total BMD and significantly decrease undercarboxylated osteocalcin, and a more favorable effect is expected when vitamin K2 is used.
Topics: Bone Density; Bone and Bones; Databases, Factual; Dietary Supplements; Humans; Osteocalcin; Randomized Controlled Trials as Topic; Vitamin D; Vitamin K; Vitamin K 2
PubMed: 32219282
DOI: 10.1039/c9fo03063h -
Revue Medicale Suisse Nov 2023
Topics: Aged; Humans; Anticoagulants; Fibrinolytic Agents; Patients; Vitamin K
PubMed: 37994603
DOI: 10.53738/REVMED.2023.19.851.2226 -
Nutrients Sep 2020Matrix gla protein (MGP) is an important vitamin K-dependent inhibitor of vascular calcification. High levels of uncarboxylated, dephosphorylated MGP have been...
Matrix gla protein (MGP) is an important vitamin K-dependent inhibitor of vascular calcification. High levels of uncarboxylated, dephosphorylated MGP have been associated with vascular calcification and are responsive to vitamin K treatment. In this systematic review, we summarize the available evidence examining whether vitamin K supplementation improves surrogate measures of cardiovascular disease including artery and valve calcification, atherosclerosis and artery stiffening. Data from controlled trials of adults were obtained by searching Ovid MEDLINE, Embase, the Cochrane Central Register of Controlled Trials and the Web of Science Core Collection. We identified nine randomized controlled trials for review, including trials of vitamin K or vitamin K supplementation, that assessed a surrogate measure of cardiovascular disease including arterial calcification, atherosclerosis or arterial stiffening. For each trial, the risk of bias was assessed applying Cochrane Collaboration methodology. The findings indicate that vitamin K does not consistently prevent progression of calcification, atherosclerosis or arterial stiffness. There may be some benefit in people with calcification at study entry. Studies were heterogenous, with relatively short follow-up and outcome measures were varied. While vitamin K supplementation clearly improves the carboxylation of dephosphoylated MGP, its role in mitigating vascular calcification is uncertain, based on current evidence.
Topics: Animals; Arteries; Atherosclerosis; Calcium-Binding Proteins; Cardiovascular Diseases; Databases, Factual; Dietary Supplements; Disease Progression; Extracellular Matrix Proteins; Humans; Randomized Controlled Trials as Topic; Vascular Calcification; Vascular Stiffness; Vitamin K; Vitamin K 2; Matrix Gla Protein
PubMed: 32977548
DOI: 10.3390/nu12102909 -
Cells Nov 2022Osteoporosis is a systemic skeletal disorder where osteoclasts are prevalent among osteoblasts. Oxidative stress is one of the main causes of osteoporosis, and nuclear...
Osteoporosis is a systemic skeletal disorder where osteoclasts are prevalent among osteoblasts. Oxidative stress is one of the main causes of osteoporosis, and nuclear factor erythroid-2-related factor 2 (Nrf2) is the master regulator of antioxidant responses. Phytol, a diterpene isolated from leaves, has many biological effects, including antimicrobial, antioxidant, and anti-inflammatory effects. This study investigated the crosstalk between Nrf2 and osteoclast differentiation in the presence of phytol. Phytol inhibited osteoclast differentiation through TRAP-positive and F-actin formation. The expression of anti-nuclear factor of activated T cells-c1 (NFATc1) and c-Fos was suppressed by phytol, as shown using Western blot and RT-PCR analysis. Phytol inhibited oxidative stress by suppressing reactive oxidant species (ROS) accumulation while recovering antioxidant enzymes, including superoxide dismutase and catalase. Additionally, phytol ameliorated osteoclast-specific differentiation, function, and oxidative stress through Nrf2 regulation by siRNA transfection. In conclusion, these data demonstrate the inhibitory effect of phytol on osteoclast differentiation through Nrf2 regulation, suggesting its potential use in oxidative stress-related osteoporosis and bone diseases.
Topics: Animals; Mice; Antioxidants; NF-E2-Related Factor 2; Osteoclasts; Osteoporosis; Oxidative Stress; Phytol; RAW 264.7 Cells
PubMed: 36429027
DOI: 10.3390/cells11223596 -
Biotechnology and Applied Biochemistry Dec 2022Cancer incidences are growing rapidly and causing millions of deaths globally. Cancer treatment is one of the most exigent challenges. Drug resistance is a natural... (Review)
Review
Cancer incidences are growing rapidly and causing millions of deaths globally. Cancer treatment is one of the most exigent challenges. Drug resistance is a natural phenomenon and is considered one of the major obstacles in the successful treatment of cancer by chemotherapy. Combination therapy by the amalgamation of various anticancer drugs has suggested modulating tumor response by targeting various signaling pathways in a synergistic or additive manner. Vitamin K is an essential nutrient and has recently been investigated as a potential anticancer agent. The combination of vitamin K analogs, such as vitamins K1, K2, K3, and K5, with other chemotherapeutic drugs have demonstrated a safe, cost-effective, and most efficient way to overcome drug resistance and improved the outcomes of prevailing chemotherapy. Published reports have shown that vitamin K in combination therapy improved the efficacy of clinical drugs by promoting apoptosis and cell cycle arrest and overcoming drug resistance by inhibiting P-glycoprotein. In this review, we discuss the mechanism, cellular targets, and possible ways to develop vitamin K subtypes into effective cancer chemosensitizers. Finally, this review will provide a scientific basis for exploiting vitamin K as a potential agent to improve the efficacy of chemotherapeutic drugs.
Topics: Humans; Vitamin K; Vitamin K 3; Vitamin K 2; Neoplasms; Vitamin K 1; Antineoplastic Agents
PubMed: 34993998
DOI: 10.1002/bab.2312 -
Molecular Cell Oct 2022The dietary factor vitamin K has been found to protect against ferroptosis, a form of cell death driven by lipid peroxidation. This reveals new dietary links to cancers...
The dietary factor vitamin K has been found to protect against ferroptosis, a form of cell death driven by lipid peroxidation. This reveals new dietary links to cancers and degenerative conditions and a key factor involved in warfarin poisoning.
Topics: Ferroptosis; Vitamin K; Warfarin; Lipid Peroxidation; Cell Death
PubMed: 36270246
DOI: 10.1016/j.molcel.2022.10.001