Vitamin K‑dependent proteins involved in bone and cardiovascular health (Review).
Level 5 - mechanism / opinion, no new human data
Narrative review describing biological mechanisms without original human data or systematic synthesis.
PubMed 29749440 · doi:10.3892/mmr.2018.8940
What was done
This narrative review describes the physiological functions of vitamin K-dependent proteins—including osteocalcin, matrix Gla protein, Gla-rich protein, growth arrest-specific protein-6 (Gas6), and periostin—in bone metabolism and vascular calcification, and discusses a hypothesized developmental link between bone and cardiovascular tissue calcification.
What was found
The abstract reports no quantitative numerical data or clinical trial results. It notes that 17 vitamin K-dependent proteins have been identified and summarizes mechanistic findings: carboxylated osteocalcin aids bone calcium deposition, while carboxylated matrix Gla protein, Gla-rich protein, and Gas6 protect endothelial cells and vascular smooth muscle cells from apoptosis and calcification. It also describes how vitamin K deficiency or antagonism promotes vascular smooth muscle cell transdifferentiation into osteoblast-like cells.
Why it matters
It synthesizes the shared biochemical and carboxylase-dependent pathways linking skeletal health to the prevention of pathological cardiovascular calcification.
Limits
As a narrative review, it lacks a systematic search protocol, formal quality appraisal of included studies, and quantitative synthesis. The abstract presents purely descriptive mechanistic hypotheses with no original experimental or clinical data.
Cited by
- supports Without adequate vitamin K2, calcium is deposited in blood vessels and forms bone spurs rather than being incorporated into bones.