HETEROGENEITY OF GLUT-4 CONTENT IN ADIPOSE AND MUSCLE-TISSUE OF MODERATELY OBESE PATIENTS WITH OR WITHOUT NON-INSULIN-DEPENDENT DIABETES-MELLITUS

We quantified Glut 4 glucose transporter content, by immunoblot technique, in adipose and muscle tissue of 6 lean controls (BMI=22+/-0.6, mean+/-SE) and 15 moderately obese patients either without (n=9, BMI=29+/-0.6) or with NIDDM (n=6, BMI=30+/-1.9). In adipose tissue, the average Glut 4 content, expressed as arbitrary densitometric units, was significantly (p<0.01) reduced in obese (0.44+/-0.06) and NIDDM patients (0.48+/-0.09) as compared to lean controls (0.93+/-0.07) and negatively correlated (r=0.66, p<0.001) to the body mass index of the studied subjects. In contrast, in muscle tissue no significant difference was observed between obese (0.54+/-0.05) or NIDDM patients (0.53+/-0.12), and lean controls (0.61+/-0.04). However, 3 out of the 15 obese patients (20%) in addition to a reduced Glut 4! content in adipose tissue also had a significantly reduced (lower than the mean content minus 2 SD of controls) Glut 4 content in muscle tissue. In conclusion: 1) In most obese patients (both with and without NIDDM) Glut 4 content is reduced in adipose but not in muscle tissue. 2) This reduction seems related to obesity rather than diabetes.