GLUT-1 or GLUT-4 transgenes in obese mice improve glucose tolerance but do not prevent insulin resistance

• Published in: American journal of physiology: endocrinology and metabolism 1999-02, Vol.276 (2), p.E390
• Main Authors: Marshall, Bess Adkins, Hansen, Polly A, Ensor, Nancy J, Ogden, M Allison, Mueckler, Mike
• Format: Article
• Language: English
• ISSN: 1522-1555
• DOI: 10.1152/ajpendo.1999.276.2.E390

Insulin-stimulated glucose uptake is defective in patients with type 2 diabetes. To determine whether transgenic glucose transporter overexpression in muscle can prevent diabetes induced by a high-fat, high-sugar diet, singly (GLUT-1, GLUT-4) and doubly (GLUT-1 and -4) transgenic mice were placed on a high-fat, high-sugar diet or a standard chow diet. On the high-fat, high-sugar diet, wild-type but not transgenic mice developed fasting hyperglycemia and glucose intolerance (peak glucose of 337 ± 19 vs. 185-209 mg/dl in the same groups on the high-fat, high-sugar diet and 293 ± 13 vs. 166-194 mg/dl on standard chow). Hyperinsulinemic clamps showed that transporter overexpression elevated insulin-stimulated glucose utilization on standard chow (49 ± 4 mg ⋅ kg ⋅ min in wild-type vs. 61 ± 4, 67 ± 5, and 63 ± 6 mg ⋅ kg ⋅ min in GLUT-1, GLUT-4, and GLUT-1 and -4 transgenic mice given 20 mU ⋅ kg ⋅ min insulin, and 54 ± 7, 85 ± 4, and 98 ± 11 in wild-type, GLUT-1, and GLUT-4 mice given 60-80 mU ⋅ kg ⋅ min insulin). On the high-fat, high-sugar diet, wild-type and GLUT-1 mice developed marked insulin resistance, but GLUT-4 and GLUT-1 and -4 mice were somewhat protected (glucose utilization during hyperinsulinemic clamp of 28.5 ± 3.4 vs. 42.4 ± 5.9, 51.2 ± 8.1, and 55.9 ± 4.9 mg ⋅ kg ⋅ min in wild type, GLUT-1, GLUT-4, GLUT-1 and -4 mice). These data demonstrate that overexpression of GLUT-1 and/or GLUT-4 enhances whole body glucose utilization and prevents the development of fasting hyperglycemia and glucose intolerance induced by a high-fat, high-sugar diet. GLUT-4 overexpression improves the insulin resistance induced by the diet. We conclude that upregulation of glucose transporters in skeletal muscle may be an effective therapeutic approach to the treatment of human type 2 diabetes.