Clinical and metabolic characteristics among young and older MZ and DZ twins
| . | Young twins . | . | Older twins . | . | ||
|---|---|---|---|---|---|---|
| . | MZ . | DZ . | MZ . | DZ . | ||
| n (M/F) | 66 (36/30) | 44 (24/20) | 42 (22/20) | 44 (16/28) | ||
| Age (years) | 28.2 ± 1.8 | 27.5 ± 1.9 | 61.6 ± 2.6 | 62.0 ± 2.0 | ||
| Birth weight (g) | 2,639.8 ± 90.1 | 2,561.8 ± 85.2 | 2,664.4 ± 72.4 | 2,703.4 ± 103.7 | ||
| BMI (kg/m2) | 24.3 ± 0.5 | 23.8 ± 0.6 | 26.2 ± 0.7 | 26.1 ± 0.9 | ||
| WHR | 0.85 ± 0.02 | 0.82 ± 0.02 | 0.90 ± 0.02 | 0.87 ± 0.02 | ||
| FFM (kg) | 54.9 ± 1.9 | 54.3 ± 2.6 | 51.1 ± 2.7 | 49.4 ± 2.4 | ||
| HGP | ||||||
| Basal | 3.10 ± 0.08 | 3.04 ± 0.08 | 3.02 ± 0.08 | 3.10 ± 0.08 | ||
| Clamp | 1.49 ± 0.07 | 1.49 ± 0.06 | 1.57 ± 0.09 | 1.70 ± 0.14 | ||
| Glucose disposal (Rd) | ||||||
| Basal | 3.10 ± 0.08 | 3.01 ± 0.07 | 3.05 ± 0.08 | 3.14 ± 0.07 | ||
| Clamp | 12.2 ± 0.53 | 11.0 ± 0.49 | 8.86 ± 0.59* | 10.84 ± 0.57 | ||
| Glucose oxidation | ||||||
| Basal | 2.17 ± 0.14 | 2.02 ± 0.15 | 1.82 ± 0.19 | 1.75 ± 0.13 | ||
| Clamp | 4.72 ± 0.19 | 4.54 ± 0.29 | 3.88 ± 0.26 | 4.27 ± 0.21 | ||
| Fat oxidation | ||||||
| Basal | 1.25 ± 0.06 | 1.32 ± 0.07 | 1.36 ± 0.08 | 1.52 ± 0.07 | ||
| Clamp | 0.32 ± 0.05 | 0.38 ± 0.09 | 0.56 ± 0.07 | 0.58 ± 0.08 | ||
| Glycolytic flux | ||||||
| Basal | 1.62 ± 0.13 | 2.00 ± 0.19 | 2.11 ± 0.17 | 2.28 ± 0.20 | ||
| Clamp | 4.49 ± 0.29 | 4.37 ± 0.30 | 3.80 ± 0.30 | 4.01 ± 0.42 | ||
| NOGM | ||||||
| Basal | 0.93 ± 0.12 | 0.99 ± 0.14 | 1.22 ± 0.17 | 1.42 ± 0.12 | ||
| Clamp | 7.53 ± 0.46 | 6.41 ± 0.42 | 4.99 ± 0.52* | 6.67 ± 0.52 | ||
| Exogenous glucose storage | ||||||
| Basal | 1.48 ± 0.14 | 1.01 ± 0.20 | 0.94 ± 0.14 | 0.86 ± 0.18 | ||
| Clamp | 7.75 ± 0.44 | 6.59 ± 0.49 | 5.06 ± 0.53* | 6.83 ± 0.55 | ||
| Insulin secretion (Di) | 2.11E-7 ± 1.14E-7 | 2.32E-7 ± 1.39E-7 | 1.10E-7 ± 0.78E-7 | 1.32E-7 ± 0.92E-7 | ||
| . | Young twins . | . | Older twins . | . | ||
|---|---|---|---|---|---|---|
| . | MZ . | DZ . | MZ . | DZ . | ||
| n (M/F) | 66 (36/30) | 44 (24/20) | 42 (22/20) | 44 (16/28) | ||
| Age (years) | 28.2 ± 1.8 | 27.5 ± 1.9 | 61.6 ± 2.6 | 62.0 ± 2.0 | ||
| Birth weight (g) | 2,639.8 ± 90.1 | 2,561.8 ± 85.2 | 2,664.4 ± 72.4 | 2,703.4 ± 103.7 | ||
| BMI (kg/m2) | 24.3 ± 0.5 | 23.8 ± 0.6 | 26.2 ± 0.7 | 26.1 ± 0.9 | ||
| WHR | 0.85 ± 0.02 | 0.82 ± 0.02 | 0.90 ± 0.02 | 0.87 ± 0.02 | ||
| FFM (kg) | 54.9 ± 1.9 | 54.3 ± 2.6 | 51.1 ± 2.7 | 49.4 ± 2.4 | ||
| HGP | ||||||
| Basal | 3.10 ± 0.08 | 3.04 ± 0.08 | 3.02 ± 0.08 | 3.10 ± 0.08 | ||
| Clamp | 1.49 ± 0.07 | 1.49 ± 0.06 | 1.57 ± 0.09 | 1.70 ± 0.14 | ||
| Glucose disposal (Rd) | ||||||
| Basal | 3.10 ± 0.08 | 3.01 ± 0.07 | 3.05 ± 0.08 | 3.14 ± 0.07 | ||
| Clamp | 12.2 ± 0.53 | 11.0 ± 0.49 | 8.86 ± 0.59* | 10.84 ± 0.57 | ||
| Glucose oxidation | ||||||
| Basal | 2.17 ± 0.14 | 2.02 ± 0.15 | 1.82 ± 0.19 | 1.75 ± 0.13 | ||
| Clamp | 4.72 ± 0.19 | 4.54 ± 0.29 | 3.88 ± 0.26 | 4.27 ± 0.21 | ||
| Fat oxidation | ||||||
| Basal | 1.25 ± 0.06 | 1.32 ± 0.07 | 1.36 ± 0.08 | 1.52 ± 0.07 | ||
| Clamp | 0.32 ± 0.05 | 0.38 ± 0.09 | 0.56 ± 0.07 | 0.58 ± 0.08 | ||
| Glycolytic flux | ||||||
| Basal | 1.62 ± 0.13 | 2.00 ± 0.19 | 2.11 ± 0.17 | 2.28 ± 0.20 | ||
| Clamp | 4.49 ± 0.29 | 4.37 ± 0.30 | 3.80 ± 0.30 | 4.01 ± 0.42 | ||
| NOGM | ||||||
| Basal | 0.93 ± 0.12 | 0.99 ± 0.14 | 1.22 ± 0.17 | 1.42 ± 0.12 | ||
| Clamp | 7.53 ± 0.46 | 6.41 ± 0.42 | 4.99 ± 0.52* | 6.67 ± 0.52 | ||
| Exogenous glucose storage | ||||||
| Basal | 1.48 ± 0.14 | 1.01 ± 0.20 | 0.94 ± 0.14 | 0.86 ± 0.18 | ||
| Clamp | 7.75 ± 0.44 | 6.59 ± 0.49 | 5.06 ± 0.53* | 6.83 ± 0.55 | ||
| Insulin secretion (Di) | 2.11E-7 ± 1.14E-7 | 2.32E-7 ± 1.39E-7 | 1.10E-7 ± 0.78E-7 | 1.32E-7 ± 0.92E-7 | ||
Data are means ± SE. All metabolic turnover rates are expressed as mg · kg FFM−1 · min−1.
P < 0.05 for MZ vs. DZ within same age-group. FFM, fat-free mass; WHR, waist-to-hip ratio.