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Physiology & Behavior Oct 2023Vitamin K2/ Menaquinones produced predominantly by the gut microbiome improve bone health and prevent coronary calcification. The central nervous system has been linked...
Vitamin K2/ Menaquinones produced predominantly by the gut microbiome improve bone health and prevent coronary calcification. The central nervous system has been linked with gut microbiota via the gut-brain axis and is strongly associated with psychiatric conditions. In the present study, we show the role of Vitamin K2 (MK-7) in gut dysbiosis-associated cognitive decline. Gut dysbiosis was induced in mice by administering Ampicillin (250 mg/kg twice a day orally) for 14 days and Vitamin K2 (0.05 mg/kg) for 21 days with or without antibiotic treatment and altered gene expression profile of intestinal microbes determined. This was followed by behavioural studies to determine cognitive changes. The behavioural observations are then correlated with proinflammatory, oxidative, and brain and intestinal histopathological changes in antibiotic-treated animals with or without vitamin K2 administration. With the use of antibiotics, Lactobacillus, Bifidobacterium, Firmicutes, and Clostridium's relative abundance reduced. When vitamin K2 was added to the medication, their levels were restored. Cognitive impairment was observed in behavioural trials in the antibiotic group, but this drop was restored in mice given both an antibiotic and vitamin K. Myeloperoxidase levels in the colon and brain increased due to gut dysbiosis, which vitamin K2 prevented. The acetylcholine esterase and oxidative stress markers brought on by antibiotics were also decreased by vitamin K2. Additionally, vitamin K2 guarded against alterations in intestine ultrastructure brought on by antibiotic use and preserved hippocampus neurons. So, it can be concluded that vitamin K2 improved cognitive skills, avoided hippocampus neuronal damage from antibiotics, and lowered intestine and brain inflammation and oxidative stress.
Topics: Mice; Animals; Vitamin K 2; Neuroprotective Agents; Dysbiosis; Anti-Bacterial Agents; Cognitive Dysfunction
PubMed: 37257737
DOI: 10.1016/j.physbeh.2023.114252 -
Calcified Tissue International Feb 2023Vitamin K, a cofactor for the γ-glutamyl carboxylase enzyme, is required for the post-translational activation of osteocalcin and matrix Gla protein, which play a key... (Review)
Review
Vitamin K, a cofactor for the γ-glutamyl carboxylase enzyme, is required for the post-translational activation of osteocalcin and matrix Gla protein, which play a key role in bone and muscle homeostasis. In vivo and in vitro models for osteoporosis and sarcopenia suggest the vitamin K could exert a positive effect in both conditions. In bone, it increases osteoblastogenesis, whilst decreases osteoclast formation and function. In muscle, it is associated with increased satellite cell proliferation and migration and might play a role in energy metabolism. Observational trials suggest that high levels of vitamin K are associated with increased bone mineral density and reduced fracture risk. However, interventional studies for vitamin K supplementation yielded conflicting results. Clinical trials in sarcopenia suggest that vitamin K supplementation could improve muscle mass and function. One of the main limitations on the vitamin K studies are the technical challenges to measure its levels in serum. Thus, they are obtained from indirect sources like food questionnaires, or levels of undercarboxylated proteins, which can be affected by other environmental or biological processes. Although current research appoints to a beneficial effect of vitamin K in bone and muscle, further studies overcoming the current limitations are required in order to incorporate this supplementation in the clinical management of patients with osteosarcopenia.
Topics: Humans; Vitamin K; Bone Density; Sarcopenia; Bone and Bones; Osteocalcin; Muscles
PubMed: 35150288
DOI: 10.1007/s00223-022-00955-3 -
Annals of the Rheumatic Diseases May 2021
Topics: Humans; Osteoarthritis, Knee; Vitamin K
PubMed: 34412026
DOI: 10.1136/annrheumdis-2020-219765 -
Trends in Molecular Medicine Oct 2022Phylloquinone (vitamin K1) and menaquinones (vitamin K2 family) are essential for post-translational γ-carboxylation of a small number of proteins, including clotting... (Review)
Review
Phylloquinone (vitamin K1) and menaquinones (vitamin K2 family) are essential for post-translational γ-carboxylation of a small number of proteins, including clotting factors. These modified proteins have now been implicated in diverse physiological and pathological processes including cancer. Vitamin K intake has been inversely associated with cancer incidence and mortality in observational studies. Newly discovered functions of vitamin K in cancer cells include activation of the steroid and xenobiotic receptor (SXR) and regulation of oxidative stress, apoptosis, and autophagy. We provide an update of vitamin K biology, non-canonical mechanisms of vitamin K actions, the potential functions of vitamin K-dependent proteins in cancer, and observational trials on vitamin K intake and cancer.
Topics: Biology; Humans; Neoplasms; Pregnane X Receptor; Proteins; Vitamin K; Vitamin K 1; Vitamin K 2
PubMed: 36028390
DOI: 10.1016/j.molmed.2022.07.002 -
Annali Di Igiene : Medicina Preventiva... 2023Aging is a complex and gradual biological process that represents the major risk factor with respect to the development of chronic degenerative diseases, often...
BACKGROUND
Aging is a complex and gradual biological process that represents the major risk factor with respect to the development of chronic degenerative diseases, often associated with disability. Diet and nu-trition, coupled with proper physical activity have a significant impact on the health status of the elderly with a decreased risk of disease being indicative of successful aging. Musculoskeletal conditions such as osteoporosis and sarcopenia are the most frequently reported disorders among the elderly community.
METHODS
This study presents a systematic review of the literature on the potential benefits of several nutra-ceuticals in promoting healthy aging and in reducing the risk of chronic diseases in elderly individuals.
RESULTS
Dietary components including vitamins (vitamin C, B vitamin and vitamin K) flavonoids (e.g., quercetin, anthocyanins, and isoflavones), minerals (e.g., magnesium, zinc and potassium) and other nutrients such phytoestrogens, amino acids, and omega-3 fatty acids help in slowing the aging process, which ultimately results in increased lifespan and longevity.
CONCLUSIONS
This paper highlights the key nutrients and phytochemicals of nutraceutical importance for the healthy aging of the elderly population. Although the scientific literature provides evidences of therapeutic effectiveness of nutraceuticals, more in-depth clinical investigations are needed.
Topics: Aged; Humans; Healthy Aging; Anthocyanins; Dietary Supplements; Vitamins; Diet; Vitamin K
PubMed: 36515582
DOI: 10.7416/ai.2022.2552 -
Sheng Wu Gong Cheng Xue Bao = Chinese... May 2021Vitamins are organic substances that are essential for the maintenance of life activities. Generally, vitamins need to be obtained from the diet or from some synthetic... (Review)
Review
Vitamins are organic substances that are essential for the maintenance of life activities. Generally, vitamins need to be obtained from the diet or from some synthetic source as the body cannot synthesize vitamins, or the amounts of the synthesized vitamins are insufficient. At present, vitamins are widely used in medicine, food additives, feed additives, cosmetics and other fields, and the global demand for vitamins is constantly growing. Vitamins can be produced from chemical or microbial synthesis. Chemical synthesis usually requires harsh reaction conditions, produces serious wastes, and creates great potential safety hazard. In contrast, microbial synthesis of vitamins is greener, safer, and requires much less energy input. This review summarizes the advances in metabolic engineering for vitamins production in the past 30 years, with a focus on production of water-soluble vitamins (vitamins B1, B2, B3, B5, B6, B7, B9, B12 and vitamin C precursors) and lipid-soluble vitamins (vitamin A, precursors of vitamin D, vitamin E and vitamin K). Moreover, the bottlenecks for fermentative production of vitamins are discussed, and future perspectives for developing next generation vitamins producing strains using synthetic biotechnology are prospected.
Topics: Biotechnology; Metabolic Engineering; Vitamin A; Vitamin K; Vitamins
PubMed: 34085453
DOI: 10.13345/j.cjb.200696 -
Nutrients Apr 2023Vitamin K occupies a unique and often obscured place among its fellow fat-soluble vitamins. Evidence is mounting, however, that vitamin K (VK) may play an important role... (Review)
Review
Vitamin K occupies a unique and often obscured place among its fellow fat-soluble vitamins. Evidence is mounting, however, that vitamin K (VK) may play an important role in the visual system apart from the hepatic carboxylation of hemostatic-related proteins. However, to our knowledge, no review covering the topic has appeared in the medical literature. Recent studies have confirmed that matrix Gla protein (MGP), a vitamin K-dependent protein (VKDP), is essential for the regulation of intraocular pressure in mice. The PREDIMED (Prevención con Dieta Mediterránea) study, a randomized trial involving 5860 adults at risk for cardiovascular disease, demonstrated a 29% reduction in the risk of cataract surgery in participants with the highest tertile of dietary vitamin K1 (PK) intake compared with those with the lowest tertile. However, the specific requirements of the eye and visual system (EVS) for VK, and what might constitute an optimized VK status, is currently unknown and largely unexplored. It is, therefore, the intention of this narrative review to provide an introduction concerning VK and the visual system, review ocular VK biology, and provide some historical context for recent discoveries. Potential opportunities and gaps in current research efforts will be touched upon in the hope of raising awareness and encouraging continued VK-related investigations in this important and highly specialized sensory system.
Topics: Mice; Animals; Vitamin K; Vitamin K 1; Vitamins; Vitamin K Deficiency; Sense Organs; Vitamin K 2
PubMed: 37111170
DOI: 10.3390/nu15081948 -
Seminars in Arthritis and Rheumatism Aug 2022Osteoarthritis (OA) is a progressive disease for which there is no disease modifying therapy. Vitamin K levels and vitamin K antagonism have been associated with risk...
OBJECTIVE
Osteoarthritis (OA) is a progressive disease for which there is no disease modifying therapy. Vitamin K levels and vitamin K antagonism have been associated with risk and progression of OA which may have direct implications for clinical management, but these observational findings are susceptible to confounding. We aimed to estimate the causal association between vitamin K and OA risk using Mendelian randomisation (MR).
METHODS
We used data from the largest genome-wide association study (GWAS) of OA to date (up to 826,690 individuals) to estimate the effect of genetically predicted vitamin K level (instrumented using four variants derived from a GWAS of 2,138 individuals) on risk of all OA types, knee, hip, spine, hand OA, and total joint replacement. We employed the inverse-variance weighted method for the primary analysis and, in a series of sensitivity analyses, adjusted for sub-genome wide significant instruments and tested for potential bias from pleiotropy.
RESULTS
We showed that genetically predicted vitamin K levels were not causally associated with risk of OA overall (OR 0.98 per unit increase in log-transformed vitamin K1; 95%CI 0.96-1.01), knee (OR 0.98; 0.92-1.03), hip (OR 0.97; 0.88-1.07), spine (OR 0.97; 0.90-1.04), hand OA (OR 0.97; 0.91-1.04) or joint replacement (OR 0.96; 0.89-1.04). Results were similar across all sensitivity analyses.
CONCLUSION
We found little evidence of a causal association between genetically predicted vitamin K and OA risk. Larger genetic and interventional studies of vitamin K are required to confirm our findings.
Topics: Genome-Wide Association Study; Humans; Mendelian Randomization Analysis; Osteoarthritis; Polymorphism, Single Nucleotide; Vitamin K
PubMed: 35667331
DOI: 10.1016/j.semarthrit.2022.152030 -
Scientific Reports Oct 2020Phytol and tocopherols and their fatty acid esters (PFAE and TFAE) are isoprenoid lipid components which can be found for instance in vegetables. Their behavior during...
Phytol and tocopherols and their fatty acid esters (PFAE and TFAE) are isoprenoid lipid components which can be found for instance in vegetables. Their behavior during maturation of fruits and vegetables could reveal valuable information on their biosynthetic formation and biological function. As pods of the genus Capsicum contain considerable amounts of both PFAE and TFAE, two cultivars (i.e. Capsicum annuum var. Forajido and Capsicum chinense var. Habanero) were grown in a greenhouse project. The date of flowering and fruit formation of each blossom was noted and fruits were harvested in four specific periods which corresponded with different stages of ripening, i.e. unripe, semi-ripe, ripe and overripe. Quantification by means of gas chromatography mass spectrometry and creation of development profiles strongly supported the suggestion that PFAE and TFAE were formed as storage molecules during fruit ripening and parallel degradation of chlorophyll. Additionally, compound-specific carbon isotope ratios (δC values (‰)) of originally in PFAE and chlorophyll bound phytol ultimately proved that PFAE, besides tocopherols, serve as sink for the cytotoxic phytol moiety released from chlorophyll degradation during fruit ripening. Furthermore, color measurements were successfully implemented to simplify the usually cumbersome separation of chili fruits into different ripening degrees.
Topics: Capsicum; Chlorophyll; Color; Fruit; Phytol; Plant Physiological Phenomena; Tocopherols
PubMed: 33057127
DOI: 10.1038/s41598-020-74308-1 -
Chlorophyll dephytylation in chlorophyll metabolism: a simple reaction catalyzed by various enzymes.Plant Science : An International... Jan 2021Chlorophyll (Chl) is composed of a tetrapyrrole ring and a phytol tail, which facilitate light energy absorbance and assembly with photosynthetic protein complexes,... (Review)
Review
Chlorophyll (Chl) is composed of a tetrapyrrole ring and a phytol tail, which facilitate light energy absorbance and assembly with photosynthetic protein complexes, respectively. Chl dephytylation, the hydrolytic removal of the phytol tail, is considered a pivotal step in diverse physiological processes, such as Chl salvage during repair of the photosystem, the Chl cycle in the adjustment of antenna size, and Chl breakdown in leaf senescence and fruit maturation. Moreover, phytol is a component of the tocopherols, a major form of vitamin E that is essential in the human diet. This phytol mostly comes from Chl hydrolysis. However, the authentic enzyme responsible for Chl dephytylation has proved elusive. CHLOROPHYLLASE (CLH) which was discovered over a century ago, was the first enzyme found to have dephytylation activity in vitro, but its role in Chl metabolism has been questioned and remains under debate. Recently, novel dephytylases, i.e., PHEOPHYTINASE (PPH) and CHLOROPHYLL DEPHYTYLASE1 (CLD1) have emerged from genetic studies, indicating that dephytylation in Chl catabolism involves different players and is more complicated than previously thought. Based on sequence homology, substrate specificity, and subcellular localization, CLH, PPH, and CLD1 belong to different types of dephytylase, which prompted us to re-examine the dilemmas and missing links that still exist in Chl metabolism. This review thus focuses on the hitherto unanswered questions involving the Chl dephytylation reaction by highlighting relevant literature, updating recent progress, and synthesizing ideas.
Topics: Chlorophyll; Photosynthesis; Phytol; Plants
PubMed: 33288004
DOI: 10.1016/j.plantsci.2020.110682