We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Altered Fiber Distribution and Fiber-Specific Glycolytic and Oxidative Enzyme Activity in Skeletal Muscle of Patients With Type 2 Diabetes.
- Authors
Oberbach, Andreas; Bossenz, Yvonne; Lehmann, Stefanie; Niebauer, Josef; Adams, Volker; Paschke, Ralf; Schön, Michael R.; Blüher, Matthias; Punkt, Karla
- Abstract
OBJECTIVE -- We investigated whether alterations of glycolytic and oxidative enzyme capacity in skeletal muscle of patients with type 2 diabetes pertain to specific muscle fibers and are associated with changes in muscle fiber composition. RESEARCH DESIGN AND METHODS -- Vastus lateralis muscle was obtained by percutaneous biopsy from 10 patients with type 2 diabetes and 15 age- and BMI-matched healthy volunteers. Using cytophotometry, muscle fiber composition and fiber type-specific glycolytic and oxidative enzyme activities were measured in slow oxidative, fast oxidative glycolytic, and fast glycolytic fibers. RESULTS -- In the whole muscle, oxidative activity was decreased in patients with type 2 diabetes. The slow oxidative fiber fraction was reduced by 16%, whereas the fast glycolytic fiber fraction was increased by 49% in skeletal muscle from the diabetic patients. Both oxidative and glycolytic enzyme activities were significantly increased in fast glycolytic and fast oxidative glycolytic fibers of type 2 diabetic patients. However, the fiber-specific ratio of glycolytic enzyme activity relative to oxidative activity was not different between type 2 diabetic patients and the control subjects. The myofibrillic ATP activity was significantly lower in all fiber types of patients with type 2 diabetes and correlates with glucose infusion rate during the steady state of a euglycemic-hyperinsulinemic clamp and maximal aerobic capacity and negatively with HbA[sub 1c] values. CONCLUSIONS -- Reduced oxidative enzyme activity in muscle of type 2 diabetic patients is most likely due to a reduction in slow oxidative fibers. Increased glycolytic and oxidative enzyme activities in individual muscle fibers are closely related to measures of long-term glycemic control and whole-body insulin sensitivity and could therefore represent a compensatory mechanism of the muscle in function of the altered glucose metabolism.
- Subjects
GLYCOLYSIS; OXIDATIVE stress; HYPOGLYCEMIC agents; CYTOPHOTOMETRY; MUSCLE diseases; TYPE 2 diabetes
- Publication
Diabetes Care, 2006, Vol 29, Issue 4, p895
- ISSN
0149-5992
- Publication type
Article
- DOI
10.2337/diacare.29.04.06.dc05-1854