Experimental Treatment of Placental Insufficiency in Animal Model (by IGF-1)

Abstract

Introduction: Fetal growth restriction occurs in up to 10 % of pregnancies, and is one of the major causes of infant mortality. The primary cause of fetal growth restriction is placental insufficiency. We suggest that insulin-like growth factor-1(IGF-1) is effective in improving placental blood circulation and corrects fetal weight deficits in animal models. Materials and Methods: The experiment was conducted in 18 pregnant Wistar rats. The animals were divided into 3 groups (intact group- laboratory rats without PI receiving placebo ; control group- laboratory rats with PI receiving placebo; experimental group- laboratory rats with PI model receiving IGF-1 via subcutaneous injections. This study was carried out in strict accordance with the recommendations in the Guide of European convention for the Protection of Vertebral Animals. The protocol was approved by the Intercollegiate Committee on the Ethics of Animal Experiments (Association of Medical universities and universities for Pharmacy & Pharmacology: Permit Number: 11-10). All surgery was performed under sodium pentobarbital anesthesia, and all efforts were made to minimize suffering. Results: All rats without PI had spontaneous labor by the end of the pregnancy. In intact group, average number of newborn rats were 9,5±1,96 and the average weight of one newborn rats was 7,38±0,095 grams. In the control group all rats delivered hypotrophic fetuses. Number of newborns in broods and their body weight did not differ significantly in the experimental animal group comparing with intact group. The mean number of newborn rats in the control group was 10,0±1,05 with the mean body mass 7,44±0,138г. Offspring's number was 25 % higher in animals treated with IGF-1 compared with the intact group (p ≤ 0,05). Discussion: Our method gave valid and reliable information proving subcutaneus insulin growth factor-1 administration reduced fetal growth restriction associated with placental insufficiency. Insulin growth factor-1 acts in response to such signals as nutrients, oxygen and hormones via the IGF receptors, and the insulin receptor. Deletion of IGF-1 gene leads to reduced birth weight.