Effects Of Autophagy Regulators And Exercise On Autophagy In Mouse Lung And JSRV Transplanted Tumor

Autophagy is a basic life phenomenon in eukaryotic cells,and plays an important role in the process of removing intracellular metabolic waste and maintaining cell homeostasis.Studies have shown that autophagy is closely related to various diseases eg.cancer.The study of autophagy usually requires to stimulate the level of autophagy,such as starvation,exercise,and autophagy regulators.In order to investigate the effect of autophagy regulators on the autophagy of mouse lung tissues and the effect of exercise on the autophagy of orthotopic transplanted tumors of JSRV nude mice,this experiment conducted the following studies:(1)Screen the optimal dose of autophagy inducer rapamycin(RAPA)to regulate lung tissue autophagy.18 Kunming mice were randomly divided into 3mg/kg,5mg/kg,7mg/kg,9mg/kg,11mg/kg group and control group.RAPA was injected intraperitoneally daily,and the control group was injected with equal amount Physiological saline.The body weight of the mice was recorded daily,the mice were sacrificed 28 days after administration,and the lung tissue was taken to extract proteins.The protein expression levels of autophagy marker proteins LC3-? and LC3-I were detected by Western blot(WB).The results show that RAPA has no significant effect on the weight of mice.Compared with the blank control group,the ratio of LC3-?/? in the 5 mg/kg and 7mg/kg group of RAPA administration groups was significantly higher than that of the control group(P<0.05).Therefore,the 5?7mg/kg RAPA in.jection has the best effect on the induction of autophagy in mouse lung tissue.(2)Screen the optimal dosage of 3-methyladenine(3-MA),an autophagy inhibitor,to regulate lung tissue autophagy.18 Kunming mice were randomly divided into 3mg/kg,5mg/kg,7mg/kg,9mg/kg,11mg/kg group and control group,and the corresponding dose of 3-MA was intraperitoneally injected daily,The control group was injected with the same amount of normal saline.The body weight of the mice was recorded daily.After 28 days of administration,the mice were sacrificed,and lung tissues were taken to extract proteins.The protein expression levels of autophagy marker proteins LC3-? and LC3-? in each administration group of 3-MA were detected by WB.The results showed that 3-MA had no significant effect on the weight of mice.Compared with the control group,the ratio of LC3-?/? in the 5mg/kg group was significantly lower than that in the blank control group(P<0.05).The LC3-II/I ratio of the 5mg/kg group was the lowest among the 3-MA administration groups.Therefore,5mg/kg 3-MA injection has the best effect on autophagy inhibition in mouse lung tissue.(3)Explore the effect of exercise on the level of autophagy in the lungs of mice.Six Kunming mice were randomly divided into an exercise group and a control group.The exercise group was forced to exercise at 25 r/min on a fatigue rotating rod instrument every day,and the control group did not do anything.After 21 days of the experiment,the mice were sacrificed,and lung tissue was taken to extract protein.The protein expression levels of autophagy marker proteins LC3-? and LC3-? in each group were detected by WB,The results showed that exercise failed to significantly affect the body weight of mice,but exercise can significantly increase the level of autophagy in the lung tissues of mice.(4)Explore the effect of exercise on the autophagy level of nude mice xenografts Twelve NUNU/B nude mice were injected subcutaneously with 0.2 mL 2 × 106 JSRV env lentivirus 72 hours after NIH3T3 cell suspension subcutaneously to construct a subcutaneous transplantation tumor model.Nude mice were randomly divided into control group,exercise group,a total of 2 groups,3 in each group.The exercise group was put into a fatigue rotating rod instrument daily for 25 minutes to force them to exercise for 30 minutes.No treatment for control group.After 21 days,the mice were sacrificed,tumor tissues were taken,their long diameter(a)and short diameter(b)were recorded,and their volume was calculated by the formula TV=1/2·a·b2.The results showed that the tumor size of the exercise group was significantly smaller than that of the control group.The above results indicate that exercise can significantly inhibit the size of JSRV subcutaneously implanted tumor in nude mice.