Effect of enteral versus parenteral nutrition on leptin gene expression and release into the circulation.
Leptin, a putative satiety hormone in rodents, is acutely regulated by fasting and refeeding. To determine the role of satiety hormones that are secreted by the gastrointestinal tract on leptin regulation, leptin mRNA and serum concentrations were measured after feeding rats similar calories with standard chow or infusion of total parenteral nutrition into the duodenum or intravenously. We have demonstrated that leptin gene expression and hormone secretion into the circulation are stimulated equally in the three experimental paradigms; it is unlikely that satiety factors secreted by the intestinal tract play a significant role in leptin regulation. Furthermore, intravenous infusion of individual components of TPN demonstrated that intravenous glucose infusion was mostly responsible for stimulation of the leptin gene and hormone secretion.
Levy
J R
JR
Section of Endocrinology and Gastroenterology, McGuire Veterans' Administration Medical Center and Medical College of Virginia, Richmond 23249, USA.
LeGall-Salmon
E
E
Santos
M
M
Pandak
W M
WM
Stevens
W
W
D017667:Adipocytes / Q000166:cytology / Q000378:metabolism*; D000273:Adipose Tissue / Q000166:cytology / Q000378:metabolism*; D000596:Amino Acids / Q000008:administration & dosage / Q000494:pharmacology; D000818:Animals; D002478:Cells, Cultured; D015342:DNA Probes; D002149:Energy Intake; D004750:Enteral Nutrition; D005217:Fat Emulsions, Intravenous / Q000008:administration & dosage / Q000494:pharmacology; D005786:Gene Expression Regulation; D005947:Glucose / Q000008:administration & dosage / Q000494:pharmacology; D007262:Infusions, Intravenous; D020738:Leptin; D008297:Male; D010289:Parenteral Nutrition, Total; D016133:Polymerase Chain Reaction; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D014158:Transcription, Genetic / Q000187:drug effects
D000596:Amino Acids; D015342:DNA Probes; D005217:Fat Emulsions, Intravenous; D020738:Leptin; D012333:RNA, Messenger; D005947:Glucose