Induction Of Zidovudine On Diabetes Mellitus In Mice

Backgorund and PurposeIncreasing occurrence of diabetes has become an emergency leading to great danger to human health.Diabetes is a metabolic disease characterized by hyperglycemia.The cause of hyperglycemia is the defect of insulin secretion,or the impairment of insulin sensitivity,or both.In the late stage of diabetes mellitus,high blood sugar for a long time can lead to complications of various tissues,including chronic injury of blood vessels,nerves,eyes,heart,kidneys,and even dysfunction.In 2015,the number of people suffering from diabetes reached 109.6 billion,of which 1.3 million died of diabetes or complications of diabetes.The main cause of death was multiple complications of diabetes,the most important of which was cardiovascular complications.The number of deaths reached 50.44%of the total diabetes-related deaths,while diabetic nephropathy accounted for 10-30%.Even so,the control effect of type 2 diabetes mellitus patients in China is not ideal.Among the diabetic patients receiving treatment,only 39.8%of them have good control of blood sugar,while only 5.6%of the patients whose blood sugar,blood pressure and blood lipid can all meet the control standard.Facing the above situation,it is very important to control and treat diabetes mellitus.Relevant studies have found that 3%-4%of patients taking zidovudine(AZT)have diabetes mellitus due to the toxic and side effects of zidovudine.At present,it is considered that this type of diabetes mellitus is type 2 diabetes mellitus.However,the specific process and mechanism of zidovudine leading to diabetes mellitus are still unclear,but zidovudine is a nucleoside reverse transcriptase inhibitor,which has some side effects,including mitochondrial toxicity,which can lead to bone marrow suppression,anemia,mitochondrial myopathy,lactic acidosis and so on.The authors believe that the toxicity of zidovudine may be due to the mitochondrial toxicity of zidovudine.Because of the impaired mitochondrial function and reduced ATP synthesis,many downstream cell metabolism and protein synthesis processes can not proceed smoothly,including the inadequate synthesis of GLUT2,GLUT4 and other diabetes-related proteins,leading to the uptake of peripheral blood sugar and diabetes mellitus.The purpose of this study is to verify the above mechanism,to unravel the inducement and mechanism of zidovudine leading to diabetes,and to give more accurate medication standards for patients with diabetes caused by zidovudine in clinical use.MethodsModelling dose study is used to determine the optimal induction dose:the mice are divided into normal group,zidovudine ultra-high dose group,zidovudine high dose group,zidovudine medium dose group,zidovudine low dose group.The latter four groups are respectively given zidovudine solution with different doses for mice to drink freely.The experiment lasts for 8 weeks,during which oral glucose tolerance test(OGTT)and insulin resistance test(IR)are performed once every 2 weeks.Blood was taken from anesthetized mice at the 8th week.Pancreas were taken.Blood was used for serum insulin concentration detection.Part of pancreatic tissue was fixed with formalin for histological examination and part was frozen for later use.Mice were divided into blank group,model group(drinking Zidovudine solution freely and eating high-energy diet),HFD group(eating high-energy diet only),AZT group(drinking Zidovudine solution only).The experiment lasted for 8 weeks.During the eight weeks,oral glucose tolerance test(OGTT)and insulin resistance test(IR)were conducted once every two weeks.After 8 weeks,Pancreas were taken.Blood was used for serum insulin concentration detection.Part of pancreatic tissue was fixed with formalin for histological examination and part was frozen for later use.Mice were divided into blank group,model group,positive treatment group,artemisinin high dose treatment group and artemisinin low dose treatment group.The model group and three treatment groups drank AZT solution freely,and at the same time were given high protein diet or high fat diet to induce diabetes in mice.The positive group was given metformin solution daily for 8 weeks.Artemisinin treatment group was given intraperitoneal injection of artesunate daily for 8 weeks,during which oral glucose tolerance test(OGTT)and insulin resistance test(IR)were performed once every 2 weeks.At the 8th week,the pancreas,quadriceps femoris,heart,white fat,brown fat and liver were taken out after anesthesia.The tissues were fixed with formalin and embedded in paraffin.Histological examination and immunohistochemical examination were carried out.Some tissues were used to detect the expression of GLUT2 and GLUT4 by PCR and WB.Some tissues were used for RCR test.Results(1)The study of modeling dose showed that low dose AZT had no effect on blood glucose of mice among the four modeling doses.Ultra-high dose AZT has the most obvious effect on improving blood sugar,but it has a higher lethal rate.High-dose AZT has more obvious effect on blood sugar than medium-dose AZT,and the mortality rate of mice is also lower.Therefore,high dose AZT(400mg/kg)was selected as the molding dose of AZT,but the diabetes molding rate of mice in high dose group was still low.(2)The effects of three methods on the formation of mouse modelsThe results of OGTT and IR in the free-drinking zidovudine solution and high-energy diet model mice were more obvious than those in the HFD and AZT groups.The blood sugar peak of OGTT was higher(P<0.05)and the fasting blood sugar was higher(P<0.05)than that in the other two groups.Therefore,the combination of two methods,i.e.free-drinking zidovudine solution and high-energy diet,could induce diabetic model in mice more quickly and obviously.(3)Therapeutic effect of metformin and artemisinin on the mouse modelMetformin and artemisinin low dose group can reduce the area under the curve of OGTT curve and fasting blood glucose in diabetic mice to some extent,but the difference is not statistically significant.The high dose group of artemisinin aggravates the condition of diabetic mice.The results of fasting blood glucose,OGTT and IR are more serious than the model group,which may be related to high dose of artesunate.(4)Through the detection of RCR,PCR and WB,the mouse diabetes model caused by this research is mitochondrial diabetes,and the occurrence and development of this disease are related to mitochondrial toxicity caused by AZT.ConclusionThe method of free drinking zidovudine solution combined with high-fat diet can be used to induce mouse diabetes model.Compared with the method of pure drinking zidovudine solution or pure eating high-fat feed,the modeling effect is more obvious.Metformin and medium-dose artesunate can relieve the diabetic model to some extent,but high-dose artesunate can aggravate the disease,so the dosage of artesunate should be paid attention to.(1)Diabetes model induced by zidovudine combined with high fat diet belongs to mitochondrial diabetes model.