Regulation of Nutrient Metabolism in Equine Skeletal Muscle and Adipose Tissue

Simple item page
dc.contributor.authorSuagee, Jessica Kanekakenreen
dc.contributor.committeecochairCorl, Benjamin A.en
dc.contributor.committeecochairWong, Eric A.en
dc.contributor.committeememberHulver, Matthew W.en
dc.contributor.committeememberGeor, Rayen
dc.contributor.committeememberMcCutcheon, L. Jillen
dc.contributor.committeememberCrisman, Mark V.en
dc.contributor.departmentAnimal and Poultry Sciencesen
dc.date.accessioned2014-03-14T21:23:01Zen
dc.date.adate2010-12-08en
dc.date.available2014-03-14T21:23:01Zen
dc.date.issued2010-10-25en
dc.date.rdate2010-12-08en
dc.date.sdate2010-11-08en
dc.description.abstractGlucose and lipid metabolism are dysregulated in obese horses. Altered glucose metabolism is evidenced by the development of insulin resistance and increased fasting plasma insulin concentrations (hyperinsulinemia) while altered lipid metabolism is evidenced by increased plasma lipid concentrations. Obesity in horses also increases the risk of the painful hoof disease, laminitis. Three experiments were performed to investigate the regulation of nutrient metabolism in skeletal muscle and adipose tissue of lean, healthy horses. Adipose tissue was found to be the primary lipogenic tissue of horses, with acetate being the primary lipogenic substrate. Secondly, ten, lean horses were used to investigate the effects of acute hyperinsulinemia on nutrient metabolism. Increasing plasma insulin concentrations to >1,000 mIU/L for six hours decreased transcript abundance of glucose transporters and the insulin receptor in adipose tissue, and decreased protein abundance of the insulin receptor in skeletal muscle, potentially indicating that hyperinsulinemia potentiates insulin resistance. Insulin infusion also reduced mRNA abundance of lipid transporters in adipose tissue while increasing them in skeletal muscle. The final experiment investigated the influence of the insulin-sensitizing drug, pioglitazone, and lipopolysaccharide, on nutrient metabolism in skeletal muscle and adipose tissue, and their association with insulin sensitivity. Pioglitazone treatment did not increase insulin sensitivity; however it did increase skeletal muscle transcript abundance of the insulin receptor and the non-insulin sensitive glucose transporter and adipose tissue protein abundance of the insulin-sensitive glucose transporter (GLUT4). Lipopolysaccharide decreased insulin sensitivity regardless of pioglitazone pre-treatment, which was associated with decreased transcript abundance of GLUT4 in skeletal muscle and adipose tissue of untreated horses, but not adipose tissue of pioglitazone treated horses.en
dc.description.degreePh. D.en
dc.identifier.otheretd-11082010-104150en
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-11082010-104150/en
dc.identifier.urihttp://hdl.handle.net/10919/40294en
dc.publisherVirginia Techen
dc.relation.haspartSuagee_JK_D_2010.pdfen
dc.relation.haspartSuagee_JK_Copyright_2010.xpsen
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subjectglucoseen
dc.subjectHorsesen
dc.subjectinsulinen
dc.subjectlaminitisen
dc.subjectObesityen
dc.titleRegulation of Nutrient Metabolism in Equine Skeletal Muscle and Adipose Tissueen
dc.typeDissertationen
thesis.degree.disciplineAnimal and Poultry Sciencesen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.leveldoctoralen
thesis.degree.namePh. D.en

Files

Original bundle
Now showing 1 - 2 of 2
Thumbnail Image
Name:
Suagee_JK_D_2010.pdf
Size:
1.53 MB
Format:
Adobe Portable Document Format
Download
Name:
Suagee_JK_Copyright_2010.xps
Size:
225.56 KB
Format:
Unknown data format
Download

Collections

Doctoral Dissertations