Dietary oleoyl-estrone delays the growth rate of young rats

Abstract

Background Oleoyl-estrone administration induces the rapid loss of fat preserving body protein. Aim of the study We intended to check whether the fat-shedding effect of oleoyl-estrone arrests growth in young rats, limiting the buildup of protein and fat. Methods Oleoyl-estrone diluted in a powdered hyperlipidic diet (33 μmol/kg) was given for 30 days to 30-day old Zucker lean (Fa/?) rats. Their body weight and food consumption were followed daily; on day 30 of treatment (60-day old rats), whole body composition (lipid, protein) was determined, and plasmaenergy parameters and leptin were measured. Results Oleoyl-estrone-treated rats grew more slowly than controls fed the hyperlipidic diet alone, and on day 60 their lipid content was about half that of controls. Protein content per kg was identical in both groups, but treated rats tended to accumulate less nitrogen and energy because of their smaller size. No changes in plasma glucose, urea, triacylglycerols, or total cholesterol were observed, but oleoyl-estrone-treated rats showed lower circulating leptin than controls. Conclusion Despite limiting the accumulation of lipids, oleoyl-estrone slowed, but did not arrest growth of young rats, nor elicit a loss of fat or protein.