Endurance training increases leptin expression in the retroperitoneal adipose tissue of rats fed with a high-sugar diet.
The presence of leptin receptors in white adipose tissue (WAT) suggests a type of peripheral control during the development of obesity and other metabolic disorders. Both diet composition and exercise influence serum leptin; however, the effect of their combination on long-term WAT leptin metabolism is unknown. In this study, rats fed with standard or high-sugar diets (HSD) were simultaneously subjected to running training for 4- and 8-week periods, and the retroperitoneal WAT (rWAT) was evaluated for adipocyte cell size, lipid and catecholamine content, Lep, OB-Rb and Ucp2 mRNA transcription levels, and circulating leptin and non-esterified fatty acids (NEFA). The HSD groups displayed a higher adiposity index and rWAT weight, Lep mRNA and protein upregulation, and a period-dependent effect on OB-Rb mRNA expression. Exercise decreased serum leptin and upregulated the OB-Rb mRNA levels. However, in rats fed with an HSD, the increase in OB-Rb mRNA and reduction in catecholamine levels resulted in a high level of adiposity and hyperleptinemia. The combination of training and an HSD decreases the NEFA levels and upregulating the Ucp2 mRNA expression in the 4-week period, while downregulating the Ucp2 mRNA expression in the 8-week period without changing the NEFA levels. Our results suggest that an HSD induces an increase in leptin expression in rWAT, while reducing adipocytes via leptin-mediated lipolysis after an 8-week period. In exercised rats fed an HSD, TAG synthesis and storage overlaps with lipolysis, promoting fat store development and Lep mRNA and plasma protein upregulation in adult rats.
Laboratório de Bioquímica e Biologia Molecular, Departamento de Ciências Biológicas, NUPEB, ICEB2, Universidade Federal de Ouro Preto, Room 045 Morro do Cruzeiro Campus, Ouro Preto, MG, 35400-000, Brazil.
Karina Barbosa
KB
de Queiroz
Juliana Bohnen
JB
Guimarães
Cândido Celso
CC
Coimbra
Gisele Vieira
GV
Rodovalho
Cláudia Martins
CM
Carneiro
Elísio Alberto
EA
Evangelista
Renata
R
Guerra-Sá
D017667:Adipocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D002395:Catecholamines / Q000378:metabolism; D048429:Cell Size / Q000187:drug effects; D004040:Dietary Carbohydrates / Q000008:administration & dosage / Q000494:pharmacology*; D005230:Fatty Acids, Nonesterified / Q000097:blood / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D050152:Intra-Abdominal Fat / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D007473:Ion Channels / Q000235:genetics / Q000378:metabolism; D020738:Leptin / Q000097:blood / Q000235:genetics* / Q000378:metabolism; D008055:Lipids / Q000032:analysis; D008066:Lipolysis / Q000187:drug effects; D008297:Male; D024101:Mitochondrial Proteins / Q000235:genetics / Q000378:metabolism; D010805:Physical Conditioning, Animal; D011863:Radioimmunoassay; D051381:Rats; D017208:Rats, Wistar; D054411:Receptors, Leptin / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D000071246:Uncoupling Protein 2
D002395:Catecholamines; D004040:Dietary Carbohydrates; D005230:Fatty Acids, Nonesterified; D007473:Ion Channels; D020738:Leptin; D008055:Lipids; D024101:Mitochondrial Proteins; D054411:Receptors, Leptin; C000604391:Ucp2 protein, rat; D000071246:Uncoupling Protein 2