Radiation Protection Of Neoandrographolide On T Lymphocytes In Mice

Objective:When exposed to the acute radiation injury,the body will undergo a series of acute or chronic stress immune processes,with the organs,tissues and cells of the body damaged to varying degrees,which may cause a threat to life when the damage is serious.Neoandrographolide is a compound of andrographolide,which is also a traditional Chinese medicine ingredient.Several studies have found that it has anti-oxidative damage effect,and has a certain protective effect on cell damage caused by radiation.As an important immune cell,T lymphocyte can resist the invasion of pathogenic microorganisms and play a great part in the immune process of the body.However,it is a kind of cell vulnerable to radiation damage.Therefore,it is of great significance to study the radiation protection of the neandrographolide against T lymphocyte.To explore the radiation protective effect of the neandroholide against T lymphocytes,our researches involving the cell proliferation,micronucleus rate,cell cycle and mitochondrial membrane potential of T lymphocytes in the process of radiation injury will be deeply explored at the cellular level.Methods:Through the reserach of pre-experiment,the optimal dose and radiation dose of this study have been obtained.Then,32 experimental mice were randomly divided into the experimental group,the drug group,the radiation group and the blank control group.In the research,the experimental group was treated with radiation+drug,the drug group was only treated with drug,the radiation group was only treated radiation,and the blank control group was untreated.Mice in the experimental group and the drug group were gavaged with neandrographolide before radiation,and then the mice in the radiation group and the blank control group were kept in the same environment for 14 days,on the12th day,there was total body irradiation one-time to the mice in the radiation group and the experimental group by ⁶⁰Co-γray 2Gy.The distance from the radiation source was100 cm,the radiation field was 80 cm×80 cm,the absorbed dose rate was 2 Gy/min,the radiation time was 1 min,the radiation dose was 2 Gy.On the 3rd day after ⁶⁰Co-γirradiation,the mice were killed by cervical dislocation and the obtained T lymphocytes would be detected experimentally.The proliferation of T lymphocytes in each group was recorded by microscope count method,through adjusting cell concentration and adding CCK8 reagent.The cells were stained with Giemsa staining solution.Next,perform the cytokinesis-block micronucleus cytome assay,and then the micronucleus of T lymphocytes in each group was observed.The apoptosis of T lymphocytes in each group was detected by PI single staining test.And the variance of mitochondrial membrane potential of T lymphocytes in each group was detected by Rhodamine123 staining.Results:（1）The proliferation rate experiment of mouse T lymphocytes:At the time of radiation and 12,24,36 and 48 hours after radiation,the T lymphocyte proliferation rate of blank control group increased by 11.2%,49.2%,59.6%,65.3%and 82%compared with radiation group（P<0.05）.Compared with the radiation group,the proliferation rate of the experimental group increased by 2.8%,13.7%,20.3%,13.5%,31.8%（P<0.05）,with the proliferation rate distribution of the drug group increasing by 5.6%,28.6%,41.7%,31.4%,45.5%（P<0.05）.（2）In the experiment of detecting the micronucleus rate of mouse T lymphocytes:The micronucleus rate of the radiation group increased by 25times compared with the blank control group（P<0.05）,and the micronucleus rate of the experimental group increased by 50%compared with the drug group（P<0.05）,the micronucleus rate of the experimental group reduced by 65.4%compared with the radiation group（P<0.05）.（3）In the experiment of detecting the cell cycle of mouse T lymphocytes:The distribution proportion of cell cycle in each group changed significantly compared with the blank control group.Compared with the radiation group,the proportion of cells in G1 phase decreased and the proportion of S phase and G2+M phase increased in the experimental group（P<0.05）.Compared with the drug group,the proportion of cells in G1 phase increased and the proportion of S phase and G2+M phase decreased in the experimental group（P<0.05）.（4）In the experiment of detecting the mitochondrial membrane potential of mouse T lymphocytes:Compared with the blank control group,the changes of other groups were significant（P<0.05）.Compared with the radiation group,the mitochondrial membrane potential of T lymphocytes increased significantly in the experimental group（P<0.05）.Conclusion:The T lymphocytes of mice will be damaged to a certain extent after exposed to a certain dose of ⁶⁰Co-γrays.Neoandrographolide can significantly reduce the micronucleus rate of T lymphocytes,reducing chromosome aberration and T lymphocyte cycle arrest,restoring the level of mitochondrial membrane potential of T lymphocytes,inhibiting the apoptosis of T lymphocytes after the mouse was irradiated.In a word,neoandrographolide has a certain radiation protective effect against T lymphocytes.