Vitamin-K1 (Phylloquinone) Prevents Sodium-fluoride (NaF)-induced Skeletal Fluorosis

Background: Skeletal fluorosis is characterized with decreased bone strength despite of increased bone mass and mineralization. It occurs result of increased bone turnover followed by increased bone mineral size and osteoid volume. Accumulating studies suggest that Vitamin-K1 regulates bone turnover and mineralization. Moreover Vitamin-K1 acceletates bone fracture healing. Objective: The aim of this study was to investigate the effect of Vitamin-K1 on NaF-induced skeletal fluorosis. Method: Four-weeks-old male Wistar rats (n=40) randomly divided into three groups. The control group (n=14) received bottled water, the NaF group (n=13) received bottled water contained 125ppm NaF and the NaF&Vitamin-K1 group (n=13) received bottled water contained 125ppm NaF together with 0.2mg/g/day Vitamin-K1 via gavaj for 12-weeks. The rats had food and water ad libitum. Sixteen-weeks-old rats were eutenized, the right femurs were removed. An average cortical bone thickness (ACBT), antero-posterior outer (APOD) and medio-lateral outer diameters (MLOD) were measured. The fracture bending stress (FBS) with three-point bending test and histological evaluations were performed. The results were analyzed with student’s t-test and Mann-Whitney U test, and presented as % mean±SD from baseline controls. The study was prospective, randomized and single-blind. Results: The results showed statistically significant increase in ACBT (+10±2; p<0.05), APOD (+7±1; p<0.05), MLOD (+9±0; p<0.05) and decrease in FBS (-15±1; p<0.05) in NaF group compared to controls. However, there was no significant difference in ACBT (+2±3), APOD (-4±3) and FBS (+5±0) in NaF&Vitamin-K1 group, except decrease in MLOD (-9±0; p<0.05) when compared to controls. Histologicaly, a widespread osteoid tissue which represents newly formed irregular bone was observed in NaF group. In NaF&Vitamin-K1 group, it was replaced with the decalcified form of bone and collagen represent regular new bone formation. However osteoid remnants were also seen. Conclusion: Vitamin-K1 prevents skeletal fluorosis in growing Wistar rats. Bilge Cadir was supported by the Cukurova University, TURKEY.