Fig. 1.

Heat map of the RT² Obesity PCR array in EF of young and old rats: RT² Obesity PCR array was performed in EF obtained from young (6 months) (female, n = 8, male n = 5) and old (30/36 months) (female n = 8, male n = 4) FBN rats. The array consisted of 84 genes belonging to orexigenic (17 genes), anorectic (54 genes), and energy expenditure (13 genes) pathways. Heat map of all genes whose expression levels were altered in old rats compared to young rats were obtained after analyses: a female EF, b male EF. Heat map of significantly altered genes in EF of old rats compared to young rats were obtained after analyses: c female EF, d male EF. The percent changes in genes that were either upregulated (>3.0-fold), downregulated (<0.3-fold) or had no change in EF (e, f) in both sexes. ↑ Upregulation, ↓ downregulation, – no change. Significance was analyzed using two-tailed Student’s t test exhibited increased expression of pancreatic and gut-derived anorectic genes such as calcitonin receptor (Calcr), colipase, pancreatic (Clps), somatostatin receptor 1 (Sstr1), and apolipoprotein A-IV (Apoa4) (p < 0.01) in aging rats compared to younger controls. Moreover, the expression of several neuropeptides (brain-derived neurotrophic factor (Bdnf),