ALVEOLAR BONE REMODELING IN HYPERCHOLESTEROLEMIC RATS TREATED WITH OMEGA 3

In previous studies we demonstrated that a high cholesterol diet is associated with a decrease in mineral density and an increase in e bone remodeling in rat tibiae. On the other hand, an omega 3 fatty acid (FA?3) rich diet could be effective in the treatment of hypercholesterolemia (HC), but its role regarding bone volume is not clear. Alveolar bone undergoes is continuously remodeled by its functional requirements and could be affected by local and systemic factors. Objective: To evaluate the effect of treatment with FA?3 on alveolar bone remodeling in rats with HC. Methods: Wistar rats were fed ad-libitum a standard diet (SD, n=16), or an atherogenic diet to induce HC (n=32). After 3 weeks: T0, HC (n=16) continued receiving the same diet, and HC?3 (n=16) received HC diet containing fish oil (rich in FA?3). At T7 and T14, 8 rats per group were euthanized. Using automated methods, serum lipid profile (mg/dL) was evaluated: Total cholesterol (T-chol), HDL-chol and triglycerides (TG). The mandibles were resected and processed for embedding in paraffin. Oriented sections were obtained (M-D) and stained with H&E. We performed the histomorphometric study on 2D digital images of interradicular bone of the first molar, using the Image Pro-Plus software: Formation (Ob.Pm), Total erosion (E.Pm) and Rest (Q.Pm) (%). Statistics: ANOVA+SNK. Results: At T7, HC presented high values of: T-chol (128.7±30.5 vs SD:64.8±10.9mg/dL; p<0.001) and TG (99.9±21.9 vs SD:55.5±18.9mg/dL; p<0.001) and low HDL-chol (32.4±7.2 vs SD:40.7±9.7mg/dL, p<0.05). At T14, HC?3 showed a lower atherogenic risk of TG (30.1±6.9 vs HC:61.9±16.5mg/dL, p<0.001) and T-chol (60.1±9.5 vs HC:138.0±41.2mg/dL, p<0.001). At T7 and T14, the HC group showed an increase in E.Pm (p<0.05). At T7, HC?3 animals did not show statistically significant differences in E.Pm compared to HC. However, at T14 we observed a decrease in E.Pm and Q.Pm (p<0.05) at the expense of an increase in Ob.Pm (p=0.01). Conclusion: The high cholesterol diet alters bone remodeling, increasing erosion. This situation could be reversed in the long term by supplementation with fish oil (source of ?3), improving bone activity parameters in hypercholesterolemia.