Carbohydrate refeeding rapidly reverses the adaptive upregulation of human skeletal muscle pyruvate dehydrogenase kinase following a high fat diet
dc.contributor.author | Bigrigg, Jonathan Kent. | en_US |
dc.date.accessioned | 2009-07-14T19:41:52Z | |
dc.date.available | 2009-07-14T19:41:52Z | |
dc.date.issued | 2004-07-14T19:41:52Z | |
dc.identifier.uri | http://hdl.handle.net/10464/2311 | |
dc.description.abstract | The time course for the reversal of the adaptive increase in pyruvate dehydrogenase kinase (PDK) activity following a 6d high fat diet (HP: 4.2 ± 0.2 % carbohydrate; 75.6 ± 0.4 % fat; 19.5 ± 0.8 % protein) was investigated in human skeletal muscle (vastus lateralis). HF feeding increased PDK activity by 44% (from 0.081 ± 0.025 min"' to 0.247 ± 0.025 mm\p < 0.05). Following carbohydrate re-feeding, (88% carbohydrate; 5% fat; 7% protein), PDK activity had returned to baseline (0.111 ± 0.014 min"') within 3h of re-feeding. The active fraction of pyruvate dehydrognease (PDHa) was depressed following 6d of the HF diet (from 0.89 ± 0.21 mmol/min/kg WW to 0.32 ± 0.05 mmol/min/kg ww,p <0.05) and increased to pre-HF levels by 45 min of post re-feeding (0.74 ±0.19 mmol/min/kg ww) and remained elevated for 3h. Western blotting analysis of the PDK isoforms, PDK4 and PDK2, revealed a 31% increase in PDK4 protein content following the HF diet, with no change in PDK2 protein. This adaptive increase in PDK4 protein content was reversed with carbohydrate re-feeding. It was concluded that the adaptive up-regulation in PDK activity and PDK4 protein content was fiilly reversed by 3h following carbohydrate re-feeding. | en_US |
dc.language.iso | eng | en_US |
dc.publisher | Brock University | en_US |
dc.subject | Pyruvate kinase. | en_US |
dc.subject | Muscle proteins. | en_US |
dc.subject | Carbohydrates in human nutrition. | en_US |
dc.title | Carbohydrate refeeding rapidly reverses the adaptive upregulation of human skeletal muscle pyruvate dehydrogenase kinase following a high fat diet | en_US |
dc.type | Electronic Thesis or Dissertation | en |
dc.degree.name | M.Sc. Applied Health Sciences | en_US |
dc.degree.level | Masters | en_US |
dc.contributor.department | Applied Health Sciences Program | en_US |
refterms.dateFOA | 2021-08-07T01:30:56Z |