| Objective: To explore the effects of prebiotics in mice lung adenocarcinoma and preliminary discuss the relationship among the flora, chronic inflammation and mice lung adenocarcinoma, prebiotics was used to intervene the urethane-induced mice lung adenocarcinoma, the level of inflammation of normal control group, lung adenocarcinoma model group and prebiotics intervention group mice in different time periods was tested, the tumor in the lung and the composition of the lung and intestinal flora in different group mice were observed.Methods: 1. A mouse model of lung adenocarcinoma was established through intraperitoneal injection of urethane(1000 mg/kg, 1 t/w, continuously 8 weeks) 2. 60 BALB/c mice were randomly divided into normal control group, lung adenocarcinoma model group, prebiotics intervention group, each group contain 20 mice. Prebiotics intervention group was given prebiotics solution(10 ml/kg) with a concentration of 50mg/ml through the method of lavage(1 t/d, 5 ds/w, a total of 16 weeks), normal control group and model group was given equal saline(1 t/d, 5 ds/w, a total of 16 weeks); The result of the lung adenocarcinoma in different group was observed, and the level of NF-κB, TNF-α, IL-1β and IL-6 in different group at the end of the 12 th week and 20 th weeks were tested respectively. 3. At the end of the 20 th week, the feces and bronchial lavage fluid(BALF) were collected respectively in normal control group, model group and prebiotics intervention group mice(n = 5), all the samples’ microbial DNA were extracted and analysed through testing the 16 S r DNA sequencing, and the difference among the three groups of mice lung and intestinal flora was analysed.Results: 1. Normal control group mice grew up steadily in the whole experimental period, model group and prebiotics intervention group mice’s body weight decreased continuously during the urethane injection period then continue to rise, and the weight of all the three group mice were similar at the end of the 20 th week; At the end of the 20 th week, normal control group mice’s lung surface did not exist nodule, each the rest mice existed obviously pulmonary nodules, and the index of lung in model and prebiotics intervention group was obviously higher than that of normal control group. 2. At the end of the 12 th and 20 th week, the level of inflammation(NF-κB, TNF-α, IL-1β and IL-6) in model group and prebiotics intervention group was higher than that of normal control group(P < 0.05), and the level of inflammation in prebiotics intervention group was lower than that of model group(P < 0.05). 3. At the end of the 20 th week, there was no statistically significant difference as the abundance, complexity(Shannon) and the level of class of the lung and intestinal flora among the normal control group, model group and prebiotics intervention group mice. In the family level and the OTU results among three groups shown some statistically significant difference, the abundant of Clostridiales in model group was lower than the normal control group, and increased to the level of control group after the intervention of the prebiotics both in lung and intestinal tract. The abundant of S24-7(one of Bacteroides) increased in model group, and decreased after the intervention of prebiotics both in lung and intestinal tract. In intestinal tract, the abundance of Bacteroidales increased in model group, and decreased after the intervention of prebiotics.Conclusion: Persistent inflammation is one of risk factors for mice lung adenocarcinoma, prebiotics can change some bacterial flora in the lung and intestinal tract, and ameliorate the environment of inflammation in the mice adenocarcinoma, the bacteria flora in the lung and intestinal may play an important role in the formation of the mice lung adenocarcinoma, related research deserves further discussion. |
