Association between sedentary behavior and force expiratory volume in 1 second reduction in middle-aged and elderly adults in communities / 中华流行病学杂志

Objective: To analyze the relationship between sedentary behavior and the force expiratory volume in 1 second (FEV1) reduction in middle-aged and elderly people in communities. Methods: The participants aged ≥40 years were randomly selected from a natural population cohort in Songjiang District, Shanghai, for pulmonary function tests and survey by using international physical activity questionnaire, a generalized additive model was used to analyze the association between sedentary behavior and FEV1 reduction in the study population and different sex-age subgroups. Results: A total of 3 121 study subjects aged ≥40 years were included. The prevalence of FEV1 reduction was 14.8%, which was higher in men than in women. There were 24.8% participants were completely sedentary. The prevalence of FEV1 reduction in women aged <60 years in complete sedentary group was 2.04 (95%CI: 1.11-3.72) times higher than that in non-complete sedentary group. In men aged <60 years, the prevalence of FEV1 reduction increased with daily sedentary time (OR=1.16, 95%CI: 1.04-1.29), and the prevalence of FEV1 reduction was also higher in those with sedentary time >5 hours/day than those with sedentary time ≤5 hours/day (OR=3.02, 95%CI: 1.28-7.16). The sensitivity analysis also found such associations. Conclusions: FEV1 reduction rate in age group <60 years was associated with sedentary behavior. Complete sedentary behavior or absence of moderate to vigorous physical activity played important roles in FEV1 reduction in women, while men were more likely to be affected by increased sedentary time, which had no association with physical activity. Reducing sedentary time to avoid complete sedentary behavior, along with increased physical activity, should be encouraged in middle-aged and elderly adults in communities to improve their pulmonary function.

The ABCG2 mRNA Synthesized in vitro Promoted Uric Acid Excretion in Mice / 中国生物化学与分子生物学报

Hyperuricemia is a chronic metabolic disease caused by the accumulation of uric acid in the body caused by purine metabolism disorder. In recent years, the incidence of hyperuricemia has increased and the age of onset is showing a younger trend. Finding effective therapeutic targets and treatment methods is a hot spot of current research. The urate transporter ATP-binding cassette subfamily G member 2 (ABCG2) is mainly expressed in the kidney and promotes uric acid excretion. In this study, ABCG2 mRNA was synthesized in vitro and transfected into hyperuricemia model mice to observe its effect on mouse uric acid levels. Firstly, the DNA template of ABCG2 mRNA was chemically synthesized, and then transcribed into mRNA in vitro, followed by modification and transfection into mouse TCMK-1 renal tubular epithelial cells. Finally, the protein expression in the cells was detected by Western blot. The results showed that the amount of protein expression in TCMK-1 cells was positively correlated with the amount of transfected mRNA (P < 0. 01), indicating a successful transfection. In animal experiments, twenty-four SPF mice were randomly divided into four groups (n = 6): control group, hyperuricemia model group, benzbromarone group [20 mg/(kg•d)] and mRNA group [2 mg/(kg•3d)]. The mice have been modeled and treated for 28 days. During this period, the body weight and growth status of the mice were monitored daily. After the treatment, the levels of serum uric acid, urine uric acid, serum creatinine, blood urea nitrogen and liver xanthine oxidase were analyzed. The results showed that compared with the model group of mice, mRNA treatment can significantly reduce the levels of serum uric acid (100. 38 ± 10. 94), blood urea nitrogen (6. 30 ± 1. 10), and serum creatinine (30. 86 ± 5. 78, P<0. 05 or P<0. 01). It can also increase the level of urine uric acid (617. 48 ± 50. 34, P<0. 05) in mice and promote the excretion of uric acid. But it has no significant effect on the activity of xanthine oxidase (26. 19 ± 2. 58) in the liver. The pathological changes of mice kidney were observed by HE staining. The results showed that compared with mice in the model group, pathological damages such as renal tubular cell edema and inflammatory cell infiltration in the mRNA treatment group were significantly improved. The relative expression of mRNA in mice kidney was detected by qRT-PCR, and the protein expression of ABCG2 in mice kidney was detected by immunohistochemistry and Western blot. The results showed that the relative expression of ABCG2 mRNA and its protein were significantly up-regulated in the kidney tissues of mice in the mRNA group (P < 0. 01), indicating that the transfection was successful in vivo. In conclusion, ABCG2 mRNA synthetized and modified in vitro can be successfully expressed in hyperuricemia mice and promote excretion of uric acid and other organic ions, as well as improvement of renal injury in mice. These results provide experimental basis for the clinical application of ABCG2 as a target for the treatment of hyperuricemia related diseases.