Effect Of Blood Glucose Control On The Expression Of Blood Exosomes MiR-21-5p And Wound Repair In Patients With Type 2 Diabetic Ulcers

Objective: To observe the effect of blood glucose control on the expression of serum exosomes miR-21-5p and wound repair in patients with diabetic skin ulcers and to explore the mechanism of blood sugar control on the repair of diabetic skin ulcer wounds,so as to provide theoretical basis for clinical application.Methods: After ethical review and approval,the fasting venous blood samples and ulcer wound tissues of 46 patients with type 2 diabetic ulcer wounds before treatment(day 1)and after treatment(day 10)were collected,All patients were divided into 2 groups according to the clinical blood sugar control situation: 30 cases in the strict blood sugar control group,16 cases in the routine blood sugar control group.There were no special restrictions on the treatment plan of the two groups of patients,the main treatment was insulin therapy,which can be supplemented by other hypoglycemic drugs.Blood glucose control goals: FBG 4.4～6.1mmol/L and 2hPBG4.4～8.0mmol/L in the strict blood sugar control group;FBG 4.4～7.0mmol/L and2 h PBG 4.4～10.0mmol/L in the routine blood sugar control group.The serum of 6healthy subjects were selected as the control group.The following main indicators of patients were Collecting:(1)General informations: name,gender,age,ethnicity,occupation,tobacco and alcohol habits,height,weight,BMI,patient source,fasting blood glucose(FBG),2 hour postprandial blood glucose(2hPBG),SBP,DBP,etc;(2)Laboratory datas: glycosylated hemoglobin(Hb A1c),albumin(ALB),globulin(GLOB),urea(UREA),uric acid(UA),creatinine(CREA),total cholesterol(TC),triglycerides(TG),High-density lipoprotein(HDL),low-density lipoprotein(LDL),white blood cells(WBC),percentage of neutrophils(NEUT%);(3)After separating the serums from the collected venous blood,store them in a refrigerator at-80℃,and then extract the exosomes.In order to identify exosomes,the three experiments in the following were carried out: Observation of the morphology and size of serum exosomes by transmission electron microscope,use NTA analysis of the size distribution and concentration of exosomes,Western Blotting method to detect the expression of the characteristic proteins of exosomes: CD63,CD9 and TSG101;(4)Quantitative Real-time PCR were used to detect the expression of miR-21-5p in serum exosomes before and after treatment;(5)Take the patient’s wound tissues before and after treatment and perform HE staining to observe the pathological changes of the ulcer wounds and immunohistochemistry to observe the expression of fibroblast-related proteins FSP-1 and Vimentin in the granulation tissues of the patient’s wounds;(6)Observe the wound healing with naked eyes after 10 days of treatment,measure the wound area and calculate the healing rate.Results:(1)Before treatment,in addition to uric acid,there were no statistically significant differences in gender,ethnicity,drinking,smoking,age,BMI,SBP,DBP,FBG,2hPBG,Hb A1 c,albumin,globulin,urea,total cholesterol,low-density lipoprotein,high-density lipoprotein,white blood cell,neutrophil percentage and triglyceride in the two groups of patients(P>0.05).(2)Comparison before and after treatment: After treatment,the FBG,2hPBG,miR-21-5p and the wound area of the strict control group were all smaller than those before treatment,and there were statistical differences(P<0.05);There were no significant differences in SBP,DBP and the wound area of the routine control group before and after treatment(P>0.05).(3)Comparison between the two groups: In the strict control group,FBG after treatment,2hPBG after treatment,miR-21-5p after treatment and wound area after treatment were smaller than those in the routine control group,The wound healing rate in the strict control group were higher than that in the routine control group,and there were statistical differences(P<0.05);There were no significant differences in SBP,DBP,FBG before treatment,2hPBG before treatment,miR-21-5p before treatment and wound area before treatment between the two groups(P>0.05).(4)Correlation analysis showed that: wound healing rate was negatively correlated with FBG after treatment(r=-0.322,P=0.045),and there was a positive correlation between miR-21-5p after treatment and 2hPBG after treatment(r=0.2945,P=0.047).(5)Visual observation of wound healing: During the treatment,the wounds of the two groups showed a tendency to heal and fresh granulation tissues were seen,the growth of granulation tissues in the strict control group were better than the routine control group,the strict control group eventually healed faster at last.(6)Immunohistochemistry showed that: After treatment,the expression of Vimentin and FSP-1 protein in the strict blood glucose control group were higher than before treatment,and there were statistical differences.(P<0.05).Conclusion: Blood glucose control may promote the healing of diabetic wounds by down-regulating the expression of serum exosomes miR-21-5p to regulate the growth of fibroblasts.