Developmental plasticity of endocrine disorders in obesity model primed by early weaning in dams.

ABSTRACT

Early weaning is associated with changes in the developmental plasticity. Here, we studied the adipocytes morphology, adipokines expression or content in adipose tissue as well as adrenal and thyroid function of neonate and adult offspring primed by early weaning. After birth, lactating rats were divided into 2 groups EW (early weaning)--dams were wrapped with a bandage to block access to milk during the last 3 days of lactation, and Control--dams whose pups had free access to milk throughout lactation (21 days). At postnatal day (PN) 21, EW pups had lower visceral and subcutaneous adipocyte area (-67.7% and -62%, respectively), body fat mass (-26%), and leptin expression in visceral adipocyte (-64%) but higher leptin expression in subcutaneous adipocyte (2.9-fold increase). Adrenal evaluations were normal, but neonate EW pups presented lower serum T3 (-55%) and TSH (-44%). At PN 180, EW offspring showed higher food intake, higher body fat mass (+21.6%), visceral and subcutaneous adipocyte area (both 3-fold increase), higher leptin (+95%) and ADRß3 (2-fold increase) content in visceral adipose tissue, and higher adiponectin expression in subcutaneous adipose tissue (+47%) but lower in visceral adipose tissue (-40%). Adult EW offspring presented higher adrenal catecholamine content (+31%), but no changes in serum corticosterone or thyroid status. Thus, early weaning primed for hypothyroidism at weaning, which can be associated with the adipocyte hypertrophy at adulthood. The marked changes in catecholamine adrenal content and visceral adipocyte ADRB3 are generally found in obesity, contributing to the development of other cardiovascular and metabolic disturbances.