Bone Quality Improvement in Ovariectomized Rats Dosed with New Osteoporosis-Preventive Compound: Analyses with Raman Spectroscopy and Polarized Light Microscopy

In this study, to observe the influence of Additive Formula Diet (AFD) ingestion in ovariectomized rats (OVX), OVX were fed a normal mineral diet (NMD) or AFD, and structures of the outer and inner regions of the cross-section of the central region of the femoral diaphysis and changes in crystalline bone quality were investigated by polarized light microscopy and Raman spectroscopy. For experimental animals, 8 rats ovariectomized at 20 weeks old were used. OVX were divided into 2 groups: NMD-fed ONMD group and AFD-fed OAFD group, and the femur was excised 24 weeks after intervention. On polarized light microscopy, the external basic lamella was thicker in the OAFD than ONMD group, showing higher-order colors. On Raman spectroscopy, the degree of calcification and crystallinity in the inner region tended to slightly higher in the OAFD than ONMD group, although crystallinity tended to slightly lower. Ingestion of AFD may have improved bone metabolism throughout the body, and improvement of the femoral mineral levels and collagen cross linkages may have more markedly improved bone quality compared with that by NMD ingestion, suggesting its usefulness for treatment of osteoporosis, bone healing after tooth extraction, and early bone formation after implant placement.