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Nutrients Nov 2023Vitamin K (VK), a fat-soluble vitamin, is essential for the clotting of blood because of its role in the production of clotting factors in the liver. Moreover,... (Review)
Review
Vitamin K (VK), a fat-soluble vitamin, is essential for the clotting of blood because of its role in the production of clotting factors in the liver. Moreover, researchers continue to explore the role of VK as an emerging novel bioactive molecule with the potential function of improving bone health. This review focuses on the effects of VK on bone health and related mechanisms, covering VK research history, homologous analogs, dietary sources, bioavailability, recommended intake, and deficiency. The information summarized here could contribute to the basic and clinical research on VK as a natural dietary additive and drug candidate for bone health. Future research is needed to extend the dietary VK database and explore the pharmacological safety of VK and factors affecting VK bioavailability to provide more support for the bone health benefits of VK through more clinical trials.
Topics: Humans; Vitamin K; Vitamin K Deficiency; Bone and Bones; Blood Coagulation; Vitamins; Vitamin K 2; Vitamin K 1
PubMed: 38068793
DOI: 10.3390/nu15234935 -
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 -
Indian Pediatrics Jun 2019
Topics: Administration, Oral; Anti-Bacterial Agents; Anti-Infective Agents; Humans; Infant, Newborn; Vitamin K
PubMed: 31278222
DOI: No ID Found -
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 -
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 -
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 -
Thrombosis and Haemostasis Nov 2017
Topics: Anticoagulants; Benzoates; Coumarins; Vitamin K
PubMed: 29202207
DOI: 10.1160/TH17-08-0594 -
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 -
Brazilian Journal of Microbiology :... Dec 2022Salmonella is an important foodborne pathogen, and it is unable to produce the quorum sensing signaling molecules called acyl-homoserine lactones (AHLs). However, it...
Salmonella is an important foodborne pathogen, and it is unable to produce the quorum sensing signaling molecules called acyl-homoserine lactones (AHLs). However, it synthesizes the SdiA protein, detecting AHL molecules, also known as autoinducer-1 (AI-1), in the external environment. Exogenous AHLs can regulate specific genes related to virulence and stress response in Salmonella. Thus, interfering with quorum sensing can be a strategy to reduce virulence and help elucidate the cell-to-cell communication role in the pathogens' response to extracellular signals. This study aimed to evaluate the influence of the quorum sensing inhibitors furanone and phytol on phenotypes regulated by N-dodecanoyl homoserine lactone (C12-HSL) in Salmonella enterica serovar Enteritidis. The furanone C30 at 50 nM and phytol at 2 mM canceled the alterations promoted by C12-HSL on glucose consumption and the levels of free cellular thiol in Salmonella Enteritidis PT4 578 under anaerobic conditions. In silico analysis suggests that these compounds can bind to the SdiA protein of Salmonella Enteritidis and accommodate in the AHL binding pocket. Thus, furanone C30 and phytol act as antagonists of AI-1 and are likely inhibitors of the quorum sensing mechanism mediated by AHL in Salmonella.
Topics: Acyl-Butyrolactones; Phytol; Trans-Activators; Bacterial Proteins; Quorum Sensing; Salmonella enteritidis; Phenotype
PubMed: 35947344
DOI: 10.1007/s42770-022-00809-y