Studies On The Radioprotective Effect Of Gallic Acid On Mice Exposed To X-ray

Objective:Radiation therapy is one of the main treatments of malignant tumors,but radiation kill tumor cells while will lead to damage to other non-tumor cells in patients,seriously affecting patient treatment and prognosis.At present,the research hotspots of radiation protection drugs are mainly focused on selecting low-toxicity and high-safety radiation protection agents to reduce the toxic side effects caused by radiotherapy.Chinese herbal medicine has low toxicity,few side effects and is widely present in plants.At present,the main components of Chinese herbal medicines include polysaccharides,alkaloids,saponins,and polyphenols,etc.,all of which have different degrees of radiation resistance.Gallic acid（GA）,also known as imes acid,is a natural polyphenolic substance with various biological activities such as scavenging free radicals,anti-oxidation,anti-tumor,anti-inflammatory,anti-microbial,and protecting the cardiovascular system.However,there are few research reports on the anti-radiation effect of GA.Therefore,this article studies the radiation protection effect of GA on mice to provide an experimental basis for further clinical research.Methods:The mice were randomly divided into negative control group,positive control group,GA group and GA protection group.The negative control group and the positive control group were given normal saline,the GA protection group was given low,medium and high doses of GA（50mg/kg,100mg/kg and 200mg/kg）,and the GA group was given high doses of GA.They were intragastric administration once a day for 14 consecutive days.On the 15th day,all patients were given a one-time X-ray irradiation of the whole body except for the negative control group and the GA group.Mice were sacrificed at different times after irradiation,and respectively detection peripheral blood WBC,thymus index,spleen index,liver’s serum catalase（CAT）,superoxide dismutase（SOD）,glutathione peroxide（GSH-Px）activity,MDA content and serum catalase（CAT）,superoxide dismutase（SOD）activity and malondialdehyde（MDA）content;bone marrow MN-PCE rate,bone marrow cell cycle changes and bone marrow cell early and late apoptosis rate.Using SPSS 24.0 software for analysis,two independent sample t-tests were used for comparison between two groups the of measurement data,using SPSS 24.0software for analysis,two independent sample t-tests were used for comparison between two groups the of measurement data,the Wilcoxon rank sum test was used for the comparison between the two groups of enumeration data,the single-factor analysis of variance was used for the comparison of the between the multiple groups of measurement data,and the comparison of measurement data between multiple groups was performed by Kruskal-Hails H test,Dunnett-t test is used for pairwise comparison of multiple measurement data,and the difference of p<0.05 was statistically significant.Results:1.The effect of GA on mouse bone marrow MN-PCE,serum and liver MDAAfter mice simply were given high-dose of GA,the rate of bone marrow MN-PCE,serum and liver MDA content were reduced,and（except for the rate of bone marrow MN-PCE）compared with the negative control group,the difference has statistically significant（p<0.05）2.The effect of different doses of GA on the number of peripheral blood white blood cells,organ index,liver CAT,SOD,GSH-Px activity,MDA content and the micronucleus rate of bone marrow polychromatic erythrocytes in mice irradiated with 2.0 Gy X-raysProphylactic administration of GA can increase the number of peripheral blood leukocytes,thymus index,spleen index,liver CAT,SOD and GSH-Px’s liveness of mice irradiatedby 2.0 Gy X-ray,and increase with the increase of GA dose（except CAT and SOD’s liveness）;and the medium dose of GA group（except medium dose CAT group）and the high-dose of GA group are compared with the positive control group,the difference was statistically significant（p<0.05,p<0.01）.Different doses of GA can reduce the content of MDA in the liver and the rate of MN-PCE in the bone marrow of mice irradiated by 2.0 Gy X-rays,and decrease with the increase of the dose of GA administration,and the medium dose of GA group and the high-dose of GA group are compared with the positive control group,the difference was statistically significant（p<0.05,p<0.01）.3.The effect of GA on the peripheral blood WBC of mice at different time after2Gy X-ray irradiation.The peripheral blood WBC of the mice decreased to the lowest 24h after 2Gy X-ray irradiation,and then gradually increased with the increase of post-irradiaation time.Prophylactic administration of GA can increase the peripheral blood WBC of mice irradiated by 2Gy X-ray after 24h,48h and 72h,and the difference is statistically significant compared with the positive control group of the same time after irradiation（p<0.05,p<0.01）.4.The effect of GA on the contents of peripheral blood WBC,organ index,antioxidant enzymes and MDA in of mice irradiated with different doses of X-rays.After the mice were irradiated with 1.0 Gy,2.0 Gy,3.0 Gy and 4.0 Gy X-rays,compared with negative controls group the mice peripheral blood WBC,thymus index,spleen index,liver CAT,SOD and GSH-Px liveness and serum CAT and SOD liveness were significantly decrease,and decreased with the increase in the absorbed dose;with the negative control group compared the amount of MDA in the mouse liver and serum was significantly increased（p<0.05,p<0.01）,and increase as the absorbed dose.Prophylactic administration of GA can increase mice irradiated by 1.0Gy,2.0 Gy,3.0 Gy and 4.0 Gy X-ray of peripheral blood WBC,thymus index,spleen index,liver CAT,SOD and GSH-Px’s liveness and serum CAT and SOD’sliveness,reduce the content of MDA in the liver and serum,and the difference is statistically significant compared with the positive control group with the same absorbed dose（p<0.05,p<0.01）.5.The effect of GA on the bone marrow MN-PCE of mice exposed to different doses of X-rays5.1 The effect of GA on MN-PCE in mouse bone marrow at different times after 2Gy X-ray irradiationThe bone marrow MN-PCE of mice was highest 24h after irradiationed by 2Gy X-ray,and then gradually decreased with the increase of post-irradiation time.Preventive GA intervention can reduce MN-PCE in mice irradiationed by 2Gy X-ray24h,48h and 72h after,and the difference is statistically significant compared with the positive control group at the same time after irradiation（p<0.01）.5.2 The effect of GA on MN-PCE in mice bone marrow irradiated with different doses of X-raysGA treatment alone reduced the bone marrow MN-PCE of mice,but the difference was not statistically significant compared with the negative control group.After the mice received 1.0 Gy,2.0 Gy,3.0 Gy and 4.0 Gy X-rays,the bone marrow MN-PCE gradually increased with the increase of the absorbed dose（1.0-3.0 Gy）,and the difference was statistically significant compared with the negative control group（p<0.01）,when the absorbed dose is 4.0Gy,the increase amplitude in bone marrow MN-PCE decreases,which may be related to bone marrow suppression,but the difference is also statistically significant compared with the negative control group（p<0.01）.Prophylactic administration of GA can reduce the bone marrow MN-PCE of mice exposed to X-rays of 1.0 Gy,2.0 Gy,3.0 Gy and 4.0 Gy,and the difference is statistically significant compared with the positive control group with the same absorbed dose（p<0.01）.6.The effect of GA on the bone marrow cell cycle of mice irradiated with different doses of X-raysGA alone reduced the ratio of G₀/G₁phase cells in mice bone marrow cells,increased the ratio of G₂/M phase and S phase cells,and the difference was statistically significant compared with the negative control（p<0.01）.After mice received 1.0,2.0,3.0 and 4.0 Gy X-rays,the proportion of bone marrow cells in G₀/G₁phase gradually increased with the increase in absorbed dose,which was different from the negative control group is statistically significant（p<0.01）;the proportion of G₂/M and S phase cells decreases,and gradually decreases with the increase of absorbed dose,which is statistically significant compared with the negative control group（p<0.01）.GA can significantly reduce the proportion of G₀/G₁phase cells in mice irradiated with 1.0,2.0,3.0 and 4.0 Gy X-rays,and increase the proportion of G₂/M phase and S phase cells and compared with the positive control group of the same absorbed dose,the difference was statistically significant（p<0.05,p<0.01）.7.The effect of GA on the apoptosis rate of bone marrow cells in mice irradi ated with different doses of X-rays7.1 Changes in the apoptotic rate of bone marrow cells in mice at different times after2.0 Gy X-ray irradiationThe early and late apoptosis rates of bone marrow cells in mice by irradiationed2.0 Gy X-ray 5h after reached the highest,and then decreased with the increase of the post-irradiation time,and each time point（except the 48h late apoptosis rate）was compared with the negative control group The differences were statistically significant（p<0.01）.7.2 The effect of GA on the apoptosis rate of bone marrow cells in mice irradiated with different doses of X-raysAfter GA treatment alone,the early and late apoptosis rate of bone marrow cells in mice was significantly reduced,and the difference was statistically significant compared with the negative control group（p<0.01）.5h after the mice were irradiated with 1.0,2.0,3.0 and 4.0 Gy X-rays,the early and late apoptosis rate of bone marrow cells gradually increased with the increase of absorbed dose（1.0-3.0 Gy）.Compared with the negative control group,the difference was statistically significant is of statistically significance（p<0.01）.When the absorbed dose is 4.0Gy,the increase amplitude in apoptosis rate decreases,which may be related to bone marrow suppression,but the difference is also statistically significant compared with the negative control group（p<0.01）.GA can reduce the early and late apoptosis rates of bone marrow cells in mice irradiated with 1.0,2.0,3.0 and 4.0 Gy X-rays,and the difference is statistically significant compared with the positive control group with the same absorbed dose（p<0.05,p<0.01）.Conclusion:1.GA can increase the number of peripheral blood white blood cells,thymus index,spleen index,liver’s CAT,SOD,GSH-Px and serum’s CAT,SOD activities of mice exposed to different doses of X-rays,and can also reduce the content of mouse liver and serum MDA;2.GA can reduce the micronucleus rate of bone marrow polychromatic erythrocytes in mice exposed to different doses of X-rays;3.GA can alleviate cell cycle arrest in G₀/G₁phase of mouse bone marrow cells irradiated with different doses of X-rays;4.GA can reduce the early and late apoptosis rate of bone marrow cells in mice irradiated with different doses of X-rays.