Lipid metabolism and resistin gene expression in insulin-resistant Fischer 344 rats.
The interrelationship between insulin and leptin resistance in young Fischer 344 (F344) rats was studied. Young F344 and Sprague-Dawley (SD) rats were fed regular chow. F344 animals had two- to threefold higher insulin and triglyceride concentrations and increased stores of triglycerides within liver and muscle. F344 animals gained more body fat. Both acyl-CoA oxidase (ACO) and carnitine palmitoyltransferase I gene expression were 20-50% less in F344 animals than in age-matched SD animals. Peroxisome proliferator-activated receptor-alpha gene expression was reduced in 70-day-old F344 animals. Finally, resistin gene expression was similar in 70-day-old SD and F344 animals. Resistin gene expression increased fivefold in F344 animals and twofold in SD animals from 70 to 130 days, without a change in insulin sensitivity. We conclude that young F344 animals have both insulin and leptin resistance, which may lead to diminished fatty oxidation and accumulation of triglycerides in insulin-sensitive target tissues. We did not detect a role for resistin in the etiology of insulin resistance in F344 animals.
Levy
James R
JR
Section of Endocrinology and Metabolism, McGuire Veterans Administration Medical Center, Richmond, Virginia 23249, USA. James.Levy@med.va.gov
Davenport
Byrd
B
Clore
John N
JN
Stevens
Wayne
W
D042962:Acyl-CoA Oxidase; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D001823:Body Composition; D001835:Body Weight; D002334:Carnitine O-Palmitoyltransferase / Q000235:genetics; D004351:Drug Resistance; D015870:Gene Expression; D005951:Glucose Tolerance Test; D006729:Hormones, Ectopic / Q000235:genetics*; D007328:Insulin / Q000032:analysis / Q000097:blood; D007333:Insulin Resistance / Q000235:genetics*; D007700:Kinetics; D020738:Leptin / Q000097:blood / Q000494:pharmacology; D050356:Lipid Metabolism; D008055:Lipids / Q000097:blood; D008099:Liver / Q000737:chemistry; D018482:Muscle, Skeletal / Q000737:chemistry; D020932:Nerve Growth Factor; D010088:Oxidoreductases / Q000235:genetics; D011506:Proteins; D051381:Rats; D011916:Rats, Inbred F344; D017207:Rats, Sprague-Dawley; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics; D052243:Resistin; D014157:Transcription Factors / Q000235:genetics; D014280:Triglycerides / Q000032:analysis
D001786:Blood Glucose; D006729:Hormones, Ectopic; D007328:Insulin; D020738:Leptin; D008055:Lipids; D011506:Proteins; D018160:Receptors, Cytoplasmic and Nuclear; D052243:Resistin; C499622:Retn protein, rat; C486575:Retnla protein, rat; D014157:Transcription Factors; D014280:Triglycerides; D020932:Nerve Growth Factor; D010088:Oxidoreductases; D042962:Acyl-CoA Oxidase; D002334:Carnitine O-Palmitoyltransferase