The expressions of insulin receptor substrate in adipocytes during catch-up growth in neonatal rats with intrauterine growth retardation
10.3969/j.issn.1000-3606.2014.12.017
- VernacularTitle:胰岛素受体底物在生长追赶宫内发育迟缓新生大鼠脂肪细胞中的表达
- Author:
Chengbin WANG
;
Ruidan ZHENG
;
Jinzhi GAO
;
Lihong LIAO
;
Juan YE
;
Yanqin YING
;
Qin NING
;
Xiaoping LUO
- Publication Type:Journal Article
- Keywords:
insulin receptor substrate;
intrauterine growth retardation;
insulin resistance;
catch-up growth;
rat
- From:
Journal of Clinical Pediatrics
2014;(12):1162-1167
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the expressions of insulin receptor substrate-1 (IRS-1) and insulin receptor sub-strate-2 (IRS-2) in adipocytes during catch-up growth in neonatal rats with intrauterine growth restriction (IUGR) and their correlations with the insulin resistance. Methods Sprague-Dawley rats (clean grade) were randomly divided into control group and food-restricted group after fertilization. Food-restricted group were received about 30%of food amount consumed in control group every day through the whole pregnant period to establish IUGR animal model, and were fed increased amount of breast-milk from postnatal day 1 to 21 to establish the period of catch-up growth in IUGR animal model (IUGR-CG). Fasting serum glu-cose, insulin and triglyceride were measured in blood from heart ventricles of 4-week old SD rats and insulin resistance index was calculated. Pre-adipocytes and mature adipocytes were obtained from SD rats at different age (1-week, 3-week, 5-week and 7-week old) and the former were induced to differentiate toward mature adipocytes. The levels of IRS-1, IRS-2 in the two kinds of mature adipocytes were detected by Real-Time PCR and Western blot. Results The expression levels of IRS-1, IRS-2 mRNA in mature adipocytes of IUGR-CG rats were signiifcantly lower than those of IUGR rats at 5-weeks and 7-weeks old (P<0.05) while the ex-pression levels of IRS-1, IRS-2 mRNA in differentiated adipocytes of IUGR-CG rats were signiifcantly lower than those of IUGR rats at 5-weeks old (P<0.05). The expression levels of IRS-1, IRS-2 protein in two kinds of adipocytes (mature and differentiated adipocytes) of IUGR-CG rats were signiifcantly lower than those of IUGR rats from postpartum week 1 through 7 (P<0.05). Conclusions IRS-1 and IRS-2 expression levels are downregulated in adipocytes during catch-up growth of IUGR rats, which may be closely related with insulin resistance.
