Evaluation Of Therapeutic Efficiency And Exploration On The Potential Mechanism Of Qingshu Ointment In Preventing And Treating Randiation-Induced Skin Toxicity

Objective:Appling compound Qingshu ointment on the esophageal cancer patients' skin of irradiated site during the radiotherapy,objectively evaluate the curative effect of Qingshu ointment on radiation-induced skin toxicity;Exploring the mechanism of action of Chinese herbal compound Qingshu ointment in pre,venting and treating on acute radiation-induced skin lesion through the basic experiment.objectively evaluate the curative effect of Qingshu ointment on radiation-induced skin toxicity.Methods:A total of 120 patients with esophageal cancer radiotherapy from December 2016 to December 2018 were enrolled in the study and randomly divided into experimental group and control group according to the drawing method.There were 60 cases in the experimental group and 60 cases in the control group.In the experimental group,compound Qingshu ointment was applied to the skin of the irradiated site before the start of radiotherapy once a day until 2 weeks after the end of radiotherapy;the skin in the control field was not treated specially.The incidence,time,severity and time of skin damage healing of the two groups during the radiotherapy were compared by clinical observation.36 male BALB/c mice were selected and irradiated with barium sulfate to remove hair in the left leg.Irradiation method:6MeV X-ray,source skin distance 100cm,dose rate 400cGy/min,irradiation dose 40Gy/time.Subsequently,the mice were randomly divided into blank group(N=12),experimental group(N=12)and control group(N=12).The blank group was not treated.The experimental group was treated with Qingshu ointment before beginning of radiotherapy once a day for a total of 56 days;while the control group was treated with Vaseline before beginning of radiotherapy,once a day,for a total of 56 days.The skin lesions in the irradiated area were observed,and appearance and healing time of skin lesion was recorded.At the end of the experiment,3 mice were randomly selected from experimental groups and control groups,and the skin tissue of the irradiated area was taken.RNA was extracted for mRNA chip detection.According to the results of chip analysis,the skin tissues of the experimental group and the irradiated group were detected by qPCR,immunohistochemistry,immunofluorescence and western blot to explore the mechanism of action of Qingshu ointment.Findings:The incidence of acute radiation-induced skin lesions in the experimental group and the control group were both 100%.The incidence of mild(Class ?+?)acute radiation-induced skin lesions was 93.3%(56 cases)and 76.7%(46 cases)in the experimental group and the control group,respectively;severe(Class ?+?)acute radiation-induced skin lesions.The incidence rates were 6.7%(4 cases)and 23.3%(14 cases),respectively.The incidence of serious radiation-induced skin lesion in the treatment group was significantly lower than that in the control group,there was significant statistical difference between them(p=0.01);acute radiation-induced skin lesion occurred before 40Gy,there were respectively 31(51.7%)and 42(70%)cases in the treatment group and control group;acute radiation-induced skin lesion occurred after 40Gy,there were respectively 42(48.3%)and 18(30%)cases in the treatment group and control group.there was significant statistical difference between them(p=0.039),Qingshu ointment can delay the occurrence time of acute radiation-induced skin lesion;the healing time of acute radiation-induced skin lesion in the treatment group was 8±2 days and that in the control group was 10±3 days.There was significant statistical difference between them(p=0.024),Qingshu ointment can significantly accelerate healing time of acute radiation-induced skin lesion.No adverse reaction related to the medicine was found in patients of the treatment group.Experimental research showed that as for grade III acute radiation-induced skin lesions,there were 9 cases in the treatment group and 4 cases in the control group;as for grade IV acute radiation-induced skin lesions,there were 3 cases in the treatment group and 8 cases in the control group.There was significant statistical difference between the two groups(p=0.04).The results of gene chip suggest that the molecular mechanism of Qingshu ointment may be related to PI3K-Akt signaling pathway.The skin tissues of the experimental group and the control group were detected by qPCR and Western blot.The expression of PIK3CB and Akt was increased in the experimental group.The literature review showed that the PI3K-Akt signaling pathway was closely related to apoptosis.The expression of apoptotic protein caspase 3 was further detected by qPCR and Western blot,It was found that the expression of caspase 3 was significantly down-regulated in the experimental group.To further confirm the above findings,the skin of mice in experimental group and control group was detected by immunohistochemistry and immunofluorescence experiment method.The results showed that Qingshu ointment could significantly increase the expression of PIK3CB and Akt genes in skin tissue of irradiated area,and down-regulate the expression of apoptotic gene caspase 3.Conclusions:Qingshu ointment can significantly reduce the severity of radiation-induced skin lesion,delay occurrence time of radiation-induced skin lesion,accelerate healing of radiation-induced skin lesion and has high safety.Qingshu ointment can significantly reduce severity of radiation-induced skin lesion of mice and the specific mechanism may be related to increasing the expression of PI3K and Akt of skin in the irradiated area,reducing the expression of apoptotic protein caspase 3 and inhibiting apoptosis induced by radioactive ray.