The Treatment Of Cla On GDM Rats And The Preliminary Exploration Of Its Mechanism

Gestational diabetes mellitus(GDM) which is inordinately abnormal glucose metabolism occurs or is discovered during pregnancy.Complications of pregnant women who suffer from GDM and fetuses are obviously rised, especially lead to macrosomia(MS)[1].The relationship of adiponectin(APN) and GDM is closed.Pre -gnant women who suffer from GDM have been discovered lower APN in blood serum. Insulin resistance(IR) which is the one of pathogenesis of GDM is refer to reduce APN[2].APN also can regulate growth and development of fetus in utero through placenta.So,increasing the APN level is a method to improve Pathological state of GDM. Prevention and treatment of GDM is focus on dietotherapy for the present.Conjugated linoleic acid(CLA) is a general word which include geometric isomers and positional isomers of linoleic acid which contain conjugate unsaturated double bond,it is natural ingredients in food and primarily exist in muscle and dairy products of ruminant animals. Resent studies have shown that[3]CLA can resist diabetes and improve IR throuth decreasing adipose tissue and the concentration of free fatty acid and improve impaired glucose tolerance.Purposes:(1)To make model of GDM rats and compare the placenta's structure with normal pregnancy rats and GDM rats .(2)Research the influence of CLA on APNmRNA of GDM rats and its possible mechanisms(3)Discussing the relationship between the expression level of APNmRNA in the placenta and birth weight of newborn mouseMethods:(1)Pregnant reproduction age SD rats were devided into three groups that included normal pregnancy group,GDM control group,diabetic CLA treatment group at random.Abdominal injection of Streptozotocin(STZ) 45mg/Kg induced GDM model in SD rats. The day of treatment with CLA ( i.g.CLA3.0g/(kg·d)) on GDM rats from the third day after injecting STZ to pregnant 19 days.(2)Glycemia,insulin,the concentration of APN were respectively detected by glucose oxidase method,radioimmuossay Kit and ELISA kit.(3)To compare the placenta's structure of normal pregnancy group and GDM control group by taking HE staining method.(4)RT-PCR was used to detect the expression level of PPAR-γmRNA and APNmRNA in adipose tissue and placenta of three groups.Results:(1)Placenta's structure of normal pregnancy rats was clear and the size of blood sinusoids were consistent and the cellwall was complete but the trophoblastic cells of GDM rats'placenta tissues were reduced and disorded and blood sinusoids'wall were break to fusion a big cavity.(2)CLA can reduce the level of glycemia and insulin of GDM rats and increase the concentration of APN in blood serum and placenta tissue that improve insulin resist.(3)The expression level of PPAR-γmRNA of adipose issue in GDM group was significantly lower than that in normal pregnancy group and the expression level of PPAR-γmRNA in CLA treatment group was significantly higher than that in GDM group,but still lower than that in normal pregnancy group. The expression level of PPAR-γmRNA of placenta in GDM group and CLA treatment group was lower than that in normal pregnancy group and the expression level of PPAR-γmRNA of placenta in CLA treatment group was higher than that in GDM group,but no statistically difference.(4)The expression level of APNmRNA of adipose issue and placenta in GDM group was significantly lower than that in normal pregnancy group and the expression level of APNmRNA in CLA treatment group was significantly higher than that in GDM group,but still lower than that in normal pregnancy group.(5)The expression level of APNmRNA in placenta was negatively correlated with the birth weight of newborn mousse.Discussions:(1)The stimulus of hyperglycemia has made function of pancreas decline and even more damage placenta tissue which is related to pregnant abnormalities.(2)The concentration of glycemia and insulin significantly decrease and the concentration of APN significantly increase after feeding CLA which indicate that CLA can improve abnormal glucose metabolism and IR and increased APN level also play protctive role.(3)The expression level of PPAR-γmRNA and APNmRNA decrease in adipose tissue in GDM.They are increased after feeding CLA which indicate that CLA can increase APN through regulating PPAR-γ. (4)There are expression of PPAR-γmRNA and APNmRNA in placenta and the expression level of APNmRNA is negatively relation to birth weight of newborn mouse. The expression level of APNmRNA is decreased but increased after feeding CLA,accordingly birth weight of newborn mouses are decreased which indicate that APN is related to the growth and development of fetus intrauterine.