The relationship between intestinal flora changes and osteoporosis in rats with inflammatory bowel disease and the improvement effect of probiotics

OBJECTIVE: The aim of this study was to investigate the relationship between the changes in intestinal flora and the occurrence of osteoporosis in rats with inflammatory bowel disease and the improvement effect of probiotics. MATERIALS AND METHODS: A total of 100 Sprague Dawley (SD) model rats with colitis were selected as research objects. All rats were randomly divided into two groups, including: bowel disease group and osteoporosis group, with 50 rats in each group. Stool samples were collected from all rats, and Lactobacillus, Escherichia coli and Bifidobacteria were cultured and counted. The relationship between the occurrence of related osteoporosis and intestinal flora was analyzed as well. Thereafter, the rats in osteoporosis group were randomly divided into two subgroups, namely, control group (n=25) and observation group (n= 25). Observation group was treated with probiotics by gastrogavage, while the control group was treated with the same volume of physiological saline. Next, the changes in serum osteoprotegerin (OPG), osteoprotegerin ligand [receptor activator of nuclear factor-kappa B ligand (RANKL)], procollagen type I carboxy-terminal propeptide (PICP), bone mineral density (BMD), bone alkaline phosphatase (BALP), tartrate-resistant acid phosphatase (TRACP), calcium concentration (Ca), and inflammatory cytokine levels were compared between the two groups after intervention. RESULTS: Osteoporosis group had significantly more Escherichia coli and notably fewer Lactobacillus and Bifidobacteria than bowel disease group (p<0.05). Pearson correlation analysis revealed that the occurrence of osteoporosis in rats with inflammatory bowel disease was negatively correlated with the count of Escherichia coli, whereas was positively related to the counts of Lactobacillus and Bifidobacteria (p<0.05). Moreover, the levels of serum OPG, PICP, TRACP, and Ca in observation group were remarkably higher than those in the control group (p<0.05). However, the levels of serum RANKL, BALP, interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (INF-gamma) were markedly lower than those in the control group (p<0.05). CONCLUSIONS: Osteoporosis in rats with inflammatory bowel disease has a negative association with the count of Escherichia coli, and a positive correlation with the counts of Lactobacillus and Bifidobacteria. In addition, treatment with probiotics can effectively alleviate osteoporosis symptoms in rats with inflammatory bowel disease by influencing the level of corresponding cytokines.