17 research outputs found
Sedentary behavior during postnatal life is determined by the prenatal environment and exacerbated by postnatal hypercaloric nutrition
The discovery of a link between in utero experience and later metabolic and cardiovascular disease is one of the most important advances in epidemiology research of recent years. There is now increasing evidence that alterations in the fetal environment have long-term consequences on metabolic and endocrine pathophysiology in adult life. This process has been termed "fetal programming," and we have shown that undernutrition of the mother during gestation leads to obesity, hypertension, hyperphagia, hyperinsulinemia, and hyperleptinemia in offspring. Using this model of maternal undernutrition throughout pregnancy, we investigated whether prenatal influences may lead to alterations in postnatal locomotor behavior, independent of postnatal nutrition. Virgin Wistar rats were time mated and randomly assigned to receive food either ad libitum (ad libitum group) or at 30% of ad libitum intake (undernourished group). Offspring from UN mothers were significantly smaller at birth than AD offspring. At weaning, offspring were assigned to one of two diets [control or hypercaloric (30% fat)]. At ages of 35 days, 145 days, and 420 days, voluntary locomotor activity was assessed. At all ages studied, offspring from undernourished mothers were significantly less active than offspring born of normal birth weight for all parameters measured, independent of postnatal nutrition. Sedentary behavior in programmed offspring was exacerbated by postnatal hypercaloric nutrition. This work is the first to clearly separate prenatal from postnatal effects and shows that lifestyle choices themselves may have a prenatal origin. We have shown that predispositions to obesity, altered eating behavior, and sedentary activity are linked and occur independently of postnatal hypercaloric nutrition. Moreover, the prenatal influence may be permanent as offspring of undernourished mothers were still significantly less active compared with normal offspring at an advanced adult age, even in the presence of a healthy diet throughout postnatal life
Dietary methyl donor deficiency during pregnancy in rats shapes learning and anxiety in offspring
Item does not contain fulltex
Neonatal leptin treatment reverses developmental programming
An adverse prenatal environment may induce long-term metabolic consequences, in particular obesity and insulin resistance. Although the mechanisms are unclear, this programming has generally been considered an irreversible change in developmental trajectory. Adult offspring of rats subjected to undernutrition during pregnancy develop obesity, hyperinsulinemia, and hyperleptinemia, especially in the presence of a high-fat diet. Reduced locomotor activity and hyperphagia contribute to the increased fat mass. Using this model of maternal undernutrition, we investigated the effects of neonatal leptin treatment on the metabolic phenotype of adult female offspring. Leptin treatment (rec-rat leptin, 2.5 ”g/g·d, sc) from postnatal d 3â13 resulted in a transient slowing of neonatal weight gain, particularly in programmed offspring, and normalized caloric intake, locomotor activity, body weight, fat mass, and fasting plasma glucose, insulin, and leptin concentrations in programmed offspring in adult life in contrast to saline-treated offspring of undernourished mothers who developed all these features on a high-fat diet. Neonatal leptin had no demonstrable effects on the adult offspring of normally fed mothers. This study suggests that developmental metabolic programming is potentially reversible by an intervention late in the phase of developmental plasticity. The complete normalization of the programmed phenotype by neonatal leptin treatment implies that leptin has effects that reverse the prenatal adaptations resulting from relative fetal undernutrition
The metabolic effects of endotoxin are differentially affected by the pattern of GH administration in the rat.
GH treatment can increase the mortality and morbidity of critically ill patients. The mechanisms of these harmful effects of GH are unknown but have been, in part, ascribed to interactions between GH and the immune system. Because GH has pattern-dependent actions we have now compared the dose-related effects of continuous and intermittent GH treatment given with or without an endotoxin (lipopolysaccharide; LPS) challenge. Male Wistar rats (n=6 per group) were treated for 5 days with recombinant human GH (0, 10, 100 or 1000 microg/kg per day) using either continuous s.c. infusion by osmotic minipump or intermittent twice daily s.c. injections. On day 4, endotoxin (5 mg/kg, i.p.) was injected and the animals monitored for a further 16 h. LPS administration alone led to neutrophilia and lymphopoenia, with increased plasma concentrations of urea, cholesterol, triglyceride, insulin and leptin, and decreased levels of IGF-I. High dose GH infusion (1000 microg/kg per day) followed by LPS caused greater increases in plasma urea, cholesterol, triglyceride, sodium and magnesium, but lower plasma glucose and insulin levels, than treatment with LPS alone. In contrast, twice daily injections of GH did not enhance these effects of endotoxin. In conclusion, the effects of endotoxin on plasma electrolytes, lipids, urea, glucose and insulin are differentially affected by the pattern of GH administration in the rat
Serum insulin-like growth factor-I concentrations in late middle age: no association with birthweight in three UK cohorts
Background:
Small body size at birth and during infancy is associated with an increased risk of adult osteoporosis and cardiovascular disease. Fetal programming of the growth hormoneâinsulin-like growth factor (GH-IGF) axis may provide a mechanism for these epidemiological findings.Aims:
To determine whether measurements of GH and IGF-I in late middle age were related to size at birth and in infancy.Methods:
Overnight urinary GH excretion and fasting serum IGF-I were measured in 309 men and 193 women from Hertfordshire (born 1920â1930) for whom birthweight and weight at 1 year were recorded. Serum IGF-I was measured in men and women from Preston (n = 254, born 1935â1943) and Sheffield (n = 215, born 1939â1940) whose birthweight and other birth measurements were recorded.Results:
Urinary GH and serum IGF-I were not related to birthweight, other measurements at birth, or weight at 1 year.Conclusion:
In contrast to previous studies in children or young adults, these data do not support the hypothesis that IGF-I concentrations are programmed by intra-uterine events, as assessed by birthweight, in late middle age