A Chinese Herb Prescription FTZ Improves Insulin Resistant Through Adipose Tissue

Insulin resistance is the common basis of obesity,diabetes,hyperlipidemia,atherosclerosis and nonalcoholic steatohepatitis.As the"common soil" of diabetes and cardiovascular diseases,insulin resistance was a world wild prevalent desease,and its therapeutic strategy has been a key problem of the Non-communicable disease control.Adipose tissue is an important endocrine organ which plays an important role in glucose and lipid metabolism.Researches of Traditional Chinese Medicine for diabetes are mostly characterized by analysis,clinical experience,clinical efficacy,etc.,which rarely investigate the mechanism from the perspective of adipose tissue.FTZ is a Chinese herb prescription based on more than 20 years clinical practice.It has an exact effect on lowering blood lipid.Previous study has proved that FTZ can accelerate the glucose update of the HepG2 cell with insulin resistace,and decreased HOMA-IR rate in rats with metabolic syndrome,but research on its mechanism is lacked.With the extension of the study found that high-fat feeding time,FTZ has some fight fat diet-induced weight gain effect,suggesting adipose tissue may play an important role.We further investigate the effects of FTZ on insulin sensitivity and to explore the underlying mechanism from the perspective of adipose tissue.Part1.The effect of FTZ on insulin resistanceObjectivePrevious studies observed the effect of FTZ on insulin sensitivity in rats with metabolic syndrome,this experiment use metformin as control,further detect FTZ’ s effect on insulin resistant mice induced by high-fat diet.Methods7 weeks’ old male C57BL/6j mice were divided into four groups:control(CON),model(MOD),metformin(MET)and FTZ after one week’ s applicability raise,with 10 mice in each group.Mice in CON and MOD group were fed with normal SPF food,while other mice with high-fat feeding for five months.At the same time,mice in CON and MOD group accepted Arab gum daily intragastric administration,and the MET group gave crude drug metformin lavage,FTZ group accept the same volume FTZ intake as well.Food intake,body weight was measured.After 4 months’ treatment,an Oral glucose tolerance test(OGTT)was conducted to measure the insulin sensitivity.We detected fast plasma glucose and insulin content to get the HOMA-IR rate.ResultsThere was no difference with food intake between the high fat feeding grougs.With the extension of high-fat feeding time,the model group gradually increased body weight,FTZ group weight gain was significantly less than the model group(P<0.05).High fat feeding raise the blood glucose as well as the area under curve,significantly(P<0.05).Mice in FTZ and MET group show lower blood glucose and the area under curve(P<0.05).To the HOMA-IR rate,group FTZ was obviously lower than MOD group which agree with the OGTT data(P<0.05).Conclusion1.FTZ can significantly improve high-fat diet-induced insulin resistance.2.FTZ reduce the bodyweight gain of mice with high fat feeding.Part2.Observation of adipose tissue function.ObjectiveAdipose tissue is the main site of lipid storage,changes in adipose tissue function can significantly affect the body’ s blood TC,TG,FFA levels,and ectopic lipid deposition.In this case,we observed lipid ectopic and lipid deposition in FTZ group and model group during high fat feeding.Changes in perivascular fat changes directly affect vascular tone,this experiment also observed blood pressure.with Pathological results,we detect the function of perivascular adipose tissue.Method18 weeks’ high-fat feeding mice of FTZ and model group were used to test blood pressure levels.Two weeks later,the mice were fasted for 12 hours and detect blood plasma TC,TG,FFA levels.The animals were sacrificed,the liver,adipose tissue around the aorta and formalin-fixed,paraffin-embedded,HE staining with pathological examination.And hepatic TC,TG were detected.Separation of various parts of the adipose tissue,such as Subcutaneous,Scapular weighed frozen spare.ResultSystolic blood pressure,diastolic blood pressure and pulse pressure of FTZ group were significantly lower than the model group(P<0.05).After 20 weeks’ treatment,fasting triglyceride and cholesterol levels in FTZ group were significantly lower(P<0.05).Each group had no significant difference in the level of free fatty acids.After 4-month treatment,the bodyweight of mice in FTZ group was much lower than mice in MOD group,as well as the blood triglyceride and blood total cholesterol levels(P<0.05).Hepatic pathology results shows that the liver of MOD group with serious lipid deposition.There were obviously vacuolar degeneration and hydropic degeneration surrounding the portal area and the central vein.A large number of inflammatory cells infiltrated,and some of liver cells dotted necrosis.The FTZ group shows much better condition,with gentleness inflammatory infiltration.The hepatic triglyceride and total cholesterol level were much lower in the FTZ group,which was consistent with the pathology results(P<0.05).Perivascular adipose tissue in MOD group were mostly single-chamber,similar to white adipose tissue;and in FTZ group,it mostly multi-cavity shape,similar to the brown adipose tissue.Conclusion1.FTZ can reduce blood TC,TG levels with no significant effect on plasma FFA;2.FTZ affect the function of perivascular fat,improve blood vessel tone,reducing endothelial lipid deposition;3.FTZ reduce ectopic lipid deposition in liver,reducing hepatic TC,TG levels.Part3.Adipose tissue plays a role in FTZ’ s effect on inproving insulin resistant.ObjectiveTo further determine adipose tissue in the role of FTZ’ s effect on improving insulin sensitivity,we use a lipoatrophy aP2 contrast transgenic diabetic mice model,and its wild-type littermate as control.MethodLipoatrophy aP2 male transgenic mice(aP2-T)and its’ wild-type littermate were randomly divided into four groups equilibrium:transgenic +gum group(CT);transgenic + FTZ group(FT);wildtype + gum group(CW)and wild-type + FTZ group(FW)according to body weight,blood glucose,blood lipids.Wild-type mice fed high-fat diet,the transgenic mice were fed ordinary SPF level.Record the food intake and body weight change during the administration.16 weeks later,oral glucose tolerance test(OGTT)was conducted,and fasting plasma insulin levels were measured to calculate HOMA-IR values,evaluate insulin sensitivity in mice in each group.ResultThe two groups with high fat feeding had no significant difference in foodintake;Mice in FT group ate less than CT group,significantly(P<0.05).Wildtype mice with FTZ treatment shows significantly improved insulin sensitivity(P<0.05),but to the transgenic mice,the effect of FTZ was not as good as the the in the wild-type mice(P>0..05).Conelusion1.Adipose tissue plays an important role in improving insulin sensitivity in FTZ;2.There may be other mechanisms of FTZ on insulin sensitivity in lipoatrophy mice.Part4.Discuss the FTZ mechanisms to improve insulin sensitivity based in adipose tissue.ObjectiveTo explore mechanisms of FTZ’ s effect on improving insulin sensitivity,analysis of adipose tissue secretion and its related mRNA expression was conducted.MethodTake small group and model group FTZ adipose tissue of mice formalin-fixed,paraffin-embedded,HE staining and morphological changes in adipose tissue,using imagine pro plus(IPP)software statistical diameter and the size of fat cells in both groups of mice,oil microscope adipose tissue macrophage infiltration.Means the use of realtime-PCR functional changes observed around epididymal adiplose tissue TNF-α,leptin,IRS-1,GLUT4 expression,such asthe evaluation of adipose tissue.Using elisa to detect serum leptin levels.ResultMale C57BL/6j mice group adipocyte volume increased significantly,and there are significant macrophage infiltration.The FTZ administration diameter and volume of fat cells in mice was significantly lower than the model group(P<0.05).Additionally,FTZ group adipose tissue macrophage infiltration lighter than the model group.RT-PCR results showed that the model group surrounding epididymal adipose tissue TNF-α,leptin expression was significantly higher than control(P<0.05);and FTZ group,TNF-α,leptin was significantly lower than the model group(P<0.05).Model group,IRS-1,GLUT4 expression levels such as increased significantly compared with the normal group(P<0.05);and FTZ group of IRS-1,GLUT4 expression was significantly lower than the model group(P<0.05).ConclusionFTZ administration can inhibit fat cell volume over-expansion,reducing adipose tissue inflammatory infiltration,reduce high-fat diet-induced adipose tissue macrophage infiltration,lead lower leptin secretion,reduced adipose tissue leptin,TNF-α,affect IRS/PI3K signaling pathway,increased IRS1 and expression of GLUT4,thereby improving insulin sensitivity.