Long term effects of normal calcium–high fat diets on body composition and bone mass, in rats.

E. HERNÁNDEZ; SUAREZ C; ; FERREIRA MONTEIRO A; ; GONZALES CHAVES M; ; PELLEGRINI G; ; ORZUZA R; ZENI S; ; FRIEDMAN S

Buenos Aires

Congreso; XXVI Reunión Anual de la AAOMM; 2009

AAOMM

Obesity and osteoporosis share a common cell progenitor. High adipocyte count in bone marrow is directly related to bone loss, as fat cells replace osteoblasts. We investigated long-term intake effect of normal calcium (Ca) diets—with different fat content—on body composition and bone mineral content (BMC), in healthy rats. At weaning (21 days), female Wistar rats (n = 30) were randomly assigned one of the following 3 groups (n = 10 each). G1 was sacrificed in order to get basal values (P0); G2 and G3 were fed ad libitum one of the two isocaloric diets (A; fat = 7% wt./wt. or B; fat = 15% wt./wt.). Mothers (M1A and M1B) were mated and mothers (M1A and M1B) and pups (P1A and P1B) were evaluated at weaning. At day 70, 20 rats from P1A and P1B (M2A and M2B, respectively) were mated and mothers (M2A and M2B) and pups (P2A and P2B) were studied at weaning. Body weights (BW), body fat (% BF) by chemical method (AOAC), total skeleton BMD, and BMC by DXA (Lunar DPX-L) in mothers and pups were evaluated. Results (mean ±SE): BW increased across reproductive cycles being significant in group B pups (P2B: 53.6 ± 1.2 > P1B: 40.7 ± 0.6 > P0: 37.4 ± 0.5; p < 0.01). BW increase because of the increment in %BF (P2B: 14.9 ±0.5 > P1B: 11.6 ± 0.7 > P0: 7.7 ± 0.3; p < 0.01); BMC decrease significantly in group B pups (C2B: 2.27 ± 0.08 > C0: 3.97 ± 0.24; p < 0.01). BMC and BMD in mothers did not reach significance. Conclusions: A long-term normal Ca–high fat diet leads to a progressive change in body composition with an increase in BF content and a decrease in BMC in pups. Awarded by UBACyT O 008.