Vitamin K2 saves the memory of ovariectomized rats against inactive Osteocalcin

Abstract

Ovariectomy (OVX) is followed by release of uncarboxylated osteocalcin (ucOC) outside
the bone. UcOC is not always that good which is a matter of controversy. Menaquinone-7(MK-7)
is an isoform of vitamin K2 with multiple effects and closely adherent to Osteocalcin. This study
was designed to investigate the effect of vitamin K2 on memory following OVX and the role of
vitamin k2 in saving it . 32 female adult fertile albino rats were subdivided into four equal groups
each containing 8 rats ( Control, K2, K2OVX, OVX). K2 and K2OVX rats received MK-7 at a dose
of 35mg/kg/Bw five days / week. Memory was tested in all four groups. In addition, serum levels
of uncarboxylated osteocalcin and sex hormones were measured. Hippocampal activity of SOD,
MDA and Glutathione peroxidase were evaluated. Also histopathological examination of brain
was performed. The memory was deteriorated significantly in OVX groups but with intake of
vitamin K2 there was non significant deterioration. Serum ucOC significant elevated in OVX rats
but in K2OVX rats the elevation was significant lower. MDA was significant higher while SOD
and Glutathione peroxidase were significant lower in ovariectomy groups. However, vitamin K2
minimized these changes. In conclusion, vitamin K2 can reduce brain oxidative stress, preserve
memory after ovariectomy.