Systemic treatment with epidermal growth factor induces anaemia in Goettingen minipigs

Nutritional anaemia dysregulates endocrine control of fetal growth

Severe anaemia is associated with increased low birth weight and Barker's hypothesis of ‘fetal origins’ proposes that a nutritional insult during critical periods of development results in adaptations that predispose individuals to adult onset diseases. We hypothesize that endocrine alterations may occur in the maternal–fetal milieu as a consequence of nutritional anaemia during pregnancy. We examined the quantitative variations in hormonal profiles in paired maternal and cord blood samples obtained from mothers and their neonates who were classified based on maternal anaemia status. Our results show that: (1) 74·6 % of the mothers enrolled in the study were anaemic, of which 85·2 % had moderate anaemia and 14·7 % had severe anaemia; (2) anthropometric parameters measured in the mothers indicate that severely anaemic mothers had a significantly low pre- and post-pregnancy weight, a significantly decreased maternal fundal height and abdominal circumference; (3) anthropometric measures in the neonates born to severely anaemic mothers show a significant reduction in ponderal index, birth weight and placental weight; (4) significant increase in both maternal, fetal insulin-like growth factor 1, ferritin levels and increased maternal erythropoietin levels were observed with an increase in severity of anaemia; (5) decreased T3and increased prolactin levels were observed in the maternal blood of severely anaemic mothers as compared with the control group. An insight into the endocrine modulation to overcome a growth disadvantage due to nutritional anaemia in pregnancy may lead to a better understanding of fetal adaptations invoked when the maternal-placental nutrient supply fails to meet the fetal nutrient demand.

Systemic treatment with epidermal growth factor causes organ growth concomitant with reduced circulating levels of IGF-I and IGFBP-3: time-dependent changes in female rats

Systemic treatment with epidermal growth factor (EGF) in neonatal rats reduces circulating levels of insulin-like growth factor I (IGF-I) and causes somatic growth retardation. In this study, we investigated the effects of EGF treatment on the IGF system and on visceral organ growth and longitudinal growth in mature rats. We treated female Wistar rats for 0 (n = 16), 1 (n = 8), 2 (n = 8), 3 (n = 8), or 4 (n = 8) weeks with subcutaneous EGF (150 microg/kg/day). The animals were weighed once a week. At sacrifice, various viscera were removed and weighed. Blood and serum samples obtained at sacrifice were analysed for growth hormone (GH), IGF-I, IGF binding proteins (IGFBPs) and various routine parameters. EGF treatment increased the total body weight. All parts of the gastrointestinal tract, the liver, the pancreas, the spleen, the bladder, the suprarenal glands and the ovaries increased proportionately more in weight than the increase in total body weight; the heart and the kidneys increased proportionately in weight whereas the weight of the perirenal fat was reduced. There were no changes in tail length but the mean length of the tibia was slightly increased in the group treated for 4 weeks with EGF. Circulating GH was unchanged but IGF-I and IGFBP-3 were reduced approximately 25 and 45%, respectively, in all EGF treated groups. There were no changes in the hepatic content of IGF-I and IGFBPs. In conclusion, systemic EGF treatment causes visceral growth concomitant with reduced circulating levels of IGF-I and IGFBP-3 in mature female rats.

Chronic treatment with epidermal growth factor stimulates growth of the urinary tract in the rat

Twenty-four male Wistar rats, 8 weeks old, were allocated into three groups and treated with human recombinant epidermal growth factor (EGF) administered subcutaneously in doses of 0, 30, and 150 micrograms/kg per day for 4 weeks. Blood sampling was done every 2nd week and urine sampling was done for 2 consecutive days every week. The most striking finding was that the ureters were dose dependently enlarged, due to growth of all layers of the ureteric wall. The urothelium of the bladder showed considerable hyperplasticity with a widening of the basal proliferative compartment and a normal differentiation pattern as observed by the expression of carbohydrate epitopes, characterized with lectinohistochemistry. Blood examination revealed a decrease in blood haemoglobin concentration and a slight increase in serum creatinine concentration in the high-dose group. There were no effects of EGF on the urinary excretion of electrolytes, proteins, and endogenous EGF.