Dietary vitamin K is remodeled by gut microbiota and influences community composition

Abstract

Vitamins have well-established roles in bacterial metabolism. Menaquinones (MKn, n = prenyl units in sidechain) are bacterially produced forms of vitamin K produced by the gut microbiota and consumed in the diet. Little is known about the influence of dietary vitamin K quinones on gut microbial composition and MKn production. Here, male and female C57BL6 mice were fed a vitamin K deficient diet or vitamin K sufficient diets containing phylloquinone (PK, plant-based vitamin K form), MK4, and/or MK9. DNA was extracted from cecal contents and 16S sequencing conducted to assess microbial composition. Cecal microbial community composition was significantly different in vitamin K deficient female mice compared to females on vitamin K sufficient diets (all p < .007). Parallel trends were seen in male mice, but were not statistically significant (all p > .05 but <0.1). Next, stable isotope-labeled vitamin K quinones were supplemented to male and female C57BL6 mice (2 H 7 PK, 13 C 11 MK4, 2 H 7 MK7, 2 H 7 MK9) and to an in vitro fermentation model inoculated with human stool (2 H 7 PK, 2 H 7 MK4, 2 H 7 MK9, or vitamin K precursor 2 H 8-menadione). Vitamin K quinones in feces and culture aliquots were measured using LC-MS. In vivo, supplemented vitamin K quinones were remodeled to other MKn (2 H 7-or 13 C 6-labeled MK4, MK10, MK11, and MK12), but in vitro only the precursor 2 H 8-menadione was remodeled to 2 H 7 MK4, 2 H 7 MK9, 2 H 7 MK10, and 2 H 7 MK11. These results suggest that dietary vitamin K deficiency alters the gut microbial community composition. Further studies are needed to determine if menadione generated by host metabolism may serve as an intermediate in dietary vitamin K remodeling in vivo.

Oral, Tongue-Coating Microbiota, and Metabolic Disorders: A Novel Area of Interactive Research

“…Microbial–host interactions closely influence human health status ( 1 , 2 ). Microorganisms colonizing the human body can participate in the synthesis and metabolism of vitamins, proteins, and lipids, promote immunity, maintain the local ecological balance in organs, degrade nutrients, provide energy to the host ( 1 , 3 , 4 ) and have an important impact on host metabolic processes. In contrast, oral microbiota have gradually gained importance as easily detectable colonizing microorganisms, and research has shifted from oral diseases to a broader perspective, of which tongue-coating microbiota are an important part.…”

Acute Cold Water-Immersion Restraint Stress Induces Intestinal Injury and Reduces the Diversity of Gut Microbiota in Mice

“…Moreover, PICRUSt2 analysis predicted that CWIR significantly downregulated metabolic pathways such as “carbohydrate metabolism”, “metabolism of cofactors and vitamins”, and “energy metabolism”. Vitamins have been demonstrated to have well-established roles in bacterial metabolism and can influence the composition of microbiota community ( Ellis et al., 2021 ). A previous study indicated that WIRS led to increased concentration of gastric mucosal lipid peroxide and myeloperoxidase activity, but decreased the gastric vitamin E ( Ohta et al., 2005 ).…”

Role of Vitamin K in Intestinal Health

“…SIBO may not increase bacterial K 2 biosynthesis in the intestine but enhance dietary K 1 absorption through the potentially damaged intestinal mucosa ( 127 ).The diversity of the gut microbiota was notably lower, and Lachnospiraceae and Ruminococcaceae greatly reduced in the VK-deficient group compared with the VK-normal group in a previous study ( 129 ). Compared with the VK-deficient group, supplemented with MK-4 and MK-9, reduced the relative abundance of cecal Bacteroides and Ruminococcus_1 while increased that of Lactobacillus at the genus level ( 130 ). Warfarin induced intestinal dysbiosis involving VK-expressing bacteria, which was related to the expression of VKOR ( 131 ).…”