Exploratory Study on Expression of Fatty Tissue in Gestational Diabetes Mouse

Abstract

Objective. To investigate the changes of UCP1 protein in brown fat by establishing a model of gestational diabetes mellitus through intervention of high fat and carbohydrate diet. To explore the changes of UCP1 protein in brown fat in gestational diabetic mice, and analyze the characteristics of abnormal glucose metabolism in gestational diabetic mice and its relationship with changes in adipocyte morphology and insulin resistance. Methods. Eighty C57BL/6J pregnant mice were randomly divided into a normal control group and a high-fat and high-sugar feeding group. The normal control group was fed a normal diet, while the high-fat and high-sugar group was fed a high-fat and high-sugar diet to establish a gestational diabetes mellitus (GDM) model. On the pregnancy days 0, 10, and 18, the weight and fasting glucose were measured. On the pregnancy day 18, the triglycerides (TG), the total cholesterol (TC), free fatty acid (FFA), insulin levels, and insulin resistance index (HOMA-IR) were measured or calculated. At the same time, brown fat UCP1 protein of the two groups of pregnant mice were measured using Western blot Observed the Adipose tissue pathological changes by staining HE. The adipocyte was observed, and the correlation was analyzed. Results. Twenty-one pregnant mice reach the level of gestational diabetes diagnosis (FBG ≥ 5.1 mmol/L) in the high-fat and high-sugar diet group. On the pregnancy day 10 and 18, the fasting plasma glucose and the body weight significantly increased ( $P<0.05$ ). The total cholesterol, triglycerides, free fatty acid, insulin level, and insulin resistance index of the GDM group were also higher compared with that of the control group ( $P<0.05$ ). The adipocyte size significantly increased in the GDM mice. TG, TC, FFA, and body weight at 18 days of gestation were significantly correlated with HOMA-IR and single-adipocyte area in the GDM mice. HOMA-IR was significantly correlated with a single-adipocyte area. Compared with the normal control group, the UCP1 proteins of GDM mice decreased significantly and negatively correlated with body weight increase. Conclusion. Feeding C57BL/6J pregnant mice with high fat and high sugar to establish a gestational diabetes mouse model has good stability and is similar to human gestational diabetes. The reduction of brown fat UCP1 protein in GDM mice has a certain correlation with obesity tendency and obvious insulin resistance.