(P03-025-23) The Intake of Yogurt With Omega-3 Fatty Acids Affects Bone Quality in Growing Wistar Rats. Influence of Previous Nutritional Status

Objectives: Omega-3 fatty acids are important on cardiovascular health, inflammation, immune system, bone development, cognition among others. The objective was to analyze the effect of the administration of yogurt alone and added with omega-3 polyunsaturated fatty acids (PUFA) particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) -free and nanoencapsulated-, as part of the usual intake, on bone quality of growing Wistar rats.

Methods: A model of renourished after severe protein malnutrition and the corresponding wellnourished control model was used. Eight groups (n=6) of wellnourished Wistar rats at weaning, were used; four of them were fed with a protein free diet until 25% of initial body weight loss. The renutrition was achieved with an experimental diet according to AIN93 (Renourished group =R) during 28 days. Another group received the same diet plus yogurt (RY group), yogurt supplemented with free omega-3 PUFA 20mg/day (RYF group) or nano encapsulated (RYN). The four groups corresponding to the wellnourished control model were C, CY, CYF and CYN. Biomechanical Testing on Femur: A three point bending mechanical test (Instron machine, model 4442; Instron Corp) was used to assess right femur biomechanical competence. The structural bone properties evaluated are as follows: load at the yielding point (Wy) and structural strength (Wfmax). Statistical analysis: two way ANOVA with simple effects and post hoc tests. Results were expressed as Mean ±SE.

Results: Wy (N): C 67,01±2,75b CY 62,38±3,30b CYF 61,5±3,09b¥ CYN 64,51±1,75b R 54,52±3,94a RY 50,89±2,83a RYF 53,73±3,70a¥ RYN 48,42±3,08a Wf max (N): C 75,36±2,11b CY 74,74±5,65b CYF 73,81±3,68b& CYN 76,44±1,57b R 62,92±4,32a RY 61,57±3,03a RYF 68,42±2,35a& RYN 58,09±4,68a. Means with one letter (a,b) in common, were not significantly different (p >0.05).(¥, &) indicates there is no difference between the groups that consumed yogurt supplemented with free omega-3 PUFA. The re-nourished animals did not recover the bony structural variables (catch up) in the time the study lasted. However, the Wy and Wfmax variables showed no significant differences between RYF and CYF.

Conclusions: Yogurt supplemented with omega-3 PUFA could be effective to recover structural bone properties in this model of re-nourishing after severe protein malnutrition.

Funding Sources: INTA 2019-PD-E7-I152