Maternal leptin treatment during lactation programs the thyroid function of adult rats.
Recently, we showed that both maternal malnutrition during lactation and leptin treatment during the neonatal period program thyroid function. In this study we evaluate whether maternal leptin treatment during lactation programs thyroid function of the offspring in the adulthood. The dams were divided into 2 groups: Lep-daily sc single injected with 8 microg/100 g of body weight with recombinant rat leptin during the last 3 days of lactation and control group (C) that received the same volume of saline. The 180 day-old animals received a single i.p. injection of (125)I (2.22x10(4) Bq) and they were killed 2 h after the injection. Triiodothyronine (T3), thyroxine (T4), thyrotropin (TSH) and leptin concentrations were measured by radioimmunoassay. The milk of leptin-treated mothers on the last day of treatment had higher leptin (p<0.05) concentration. The pups of the leptin-treated mothers had at 21 days an unchanged T3, T4 and leptin serum concentrations with higher TSH (p<0.05). The offspring of Lep mothers had at 180 days a higher T3 (p<0.05) with normal thyroid (125)I uptake, T4 and TSH serum concentrations compared to the controls. So, the mother's hyperleptinaemia during lactation programs to a higher T3 serum concentration on the offspring, probably by a higher leptin transfer through the milk.
Passos
Magna Cottini Fonseca
MC
Department of Applied Nutrition, Nutrition Institute, State University of Rio de Janeiro, 20550-030, Rio de Janeiro, RJ, Brazil. magna@uerj.br
Lins
Márcia Clements
MC
Lisboa
Patrícia Cristina
PC
Toste
Fabiane Pereira
FP
Bonomo
Isabela Teixeira
IT
de Moura
Egberto Gaspar
EG
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D005260:Female; D007457:Iodine Radioisotopes / Q000032:analysis; D007774:Lactation; D020738:Leptin / Q000008:administration & dosage / Q000097:blood / Q000502:physiology*; D011863:Radioimmunoassay; D051381:Rats; D013961:Thyroid Gland / Q000187:drug effects / Q000502:physiology*; D013963:Thyroid Hormones / Q000097:blood / Q000378:metabolism*; D013972:Thyrotropin / Q000097:blood / Q000378:metabolism; D013974:Thyroxine / Q000097:blood / Q000378:metabolism; D014284:Triiodothyronine / Q000097:blood / Q000378:metabolism
D007457:Iodine Radioisotopes; D020738:Leptin; D013963:Thyroid Hormones; D014284:Triiodothyronine; D013972:Thyrotropin; D013974:Thyroxine