Desphospho-Uncarboxylated Matrix-Gla Protein Is Increased Postoperatively in Cardiovascular Risk Patients (Dahlberg et al.)
Matrix Gla protein (MGP) is an extrahepatic protein that is dependent on glutamate carboxylation, a vitamin K-dependent process. Its inactive form, desphospho-uncarboxylated-MGP, has been associated with increased arterial calcification and stiffness. A study published in Nutrients sought to measure the degree of postoperative carboxylation, or activation, of MGP and two other Gla proteins in patients scheduled for abdominal or orthopaedic surgery.
Forty patients undergoing abdominal or orthopaedic surgery were included. Blood samples were collected preoperatively and four days after the surgery for 40 patients undergoing abdominal or orthopaedic surgery. Desphospho-carboxylated MGP (dp-cMGP), desphospho-uncarboxylated MGP (dp-ucMGP), carboxylated osteocalcin (OC) (cOC), uncarboxylated OC (ucOC), and uncarboxylated prothrombin (PIVKA-II) were analyzed.
The results showed, preoperatively, 29 patients had dp-ucMGP levels above the reference values. Patients with pre-existing cardiovascular comorbidities had higher dp-ucMGP preoperatively compared with patients with no record of cardiovascular disease. Postoperatively, this number increased to 36 patients, and median dp-ucMGP levels increased (p < 0.0001) and correlated to a PIVKA-II increase (r = 0.44). On the other hand, dp-cMGP levels did not significantly alter. Decreased levels of ucOC and cOC were seen after surgery (p = 0.017 and p = 0.0033, respectively). Comorbidities, possible nutritional defects, and complications affecting Gla protein activity and function were identified.
The researchers concluded that inactive MGP was high preoperatively, and had further increased postoperatively. This pattern was linked to several comorbidities, possible nutritional defects, and postoperative complications, which motivates further research about potential interactions between perioperative corrective treatments with vitamin K supplements, cardiovascular biomarkers, and incidents of stroke and myocardial infarction events.
While this study did not include a high number of participants, Dr. Katarzyna Maresz, president of the International Science and Health Foundation, feels it points to an interesting new category for K2 usage. “We have here new category… post-operational patients. It can be very dangerous for patients to have their Vitamin K2 status worsen, so it is interesting to consider the benefits K supplementation could provide to patients before they undergo a procedure.”
Reference:
Dahlberg S et al. “Desphospho-Uncarboxylated Matrix-Gla Protein Is Increased Postoperatively in Cardiovascular Risk Patients.” Nutrients. 2018 Jan 5;10(1). pii: E46. doi: 10.3390/nu10010046.