RESUMO
Catch-up growth (CUG) after food restriction can increase the risks for insulin resistance-related diseases, and to our knowledge, no previous studies have addressed how bone is influenced by CUG when refeeding diet content differs. The objective of this study was to investigate the bone status resulting from CUG induced by varying refeeding dietary patterns, and to assess the potential influencing factors and the effect of resveratrol on bone status during CUG. Experimental rats were randomly divided into five groups: normal chow (NC) group; CUG group (CUG, containing two subgroups, respectively, refeeding with normal chow or high-fat diet); high-fat diet (HF) group; and resveratrol intervention groups (CUGE and HFE). Bone parameters were detected by dual-energy X-ray absorptiometry. Serum concentrations of tumor necrosis factor (TNF)-α, body weight and food intake were also recorded. Our results showed that food restriction induced a significant decrease in bone parameters. Eight-week CUG by normal chow had a greater degree of improvement in bone mineral density than high-fat diet, and even returned to normal level similar to NC. Bone parameters were elevated in varying degrees in the HF group compared with the NC group. In the resveratrol intervention groups, bone parameters significantly increased. Furthermore, bone parameters were inversely related with serum TNF-α concentrations, but showed positive correlation with body weight. In conclusion, the study shows that CUG can partially reverse the deleterious effects of caloric restriction on bone health, especially in the refeeding with normal chow group. Moreover, resveratrol has a protective effect on bone status during the period of CUG. Serum TNF-α levels and body weight also seem to play an important role in regulating bone parameters.