Table 1.
Effects of IGF-1/IGFBP-3 on glucose metabolism, lipid metabolism, body composition, and hormones
| Baseline | Month 3 | Change | P value | |
|---|---|---|---|---|
| Oral glucose tolerance test (n = 10) | ||||
| Glucose (mg/dl) t = 0 min | 105 ± 3 | 98 ± 2 | −8 ± 2 | 0.005 |
| Glucose (mg/dl) t = 120 min | 166 ± 11 | 134 ± 13 | −32 ± 9 | 0.008 |
| Glucose AUC | 481 ± 24 | 433 ± 23 | −48 ± 20 | 0.04 |
| Insulin (μIU/ml) t = 0 min | 21.0 ± 2.6 | 15.1 ± 1.9 | −5.9 ± 2.8 | 0.06 |
| Insulin (μIU/ml) t = 120 min | 160.5 ± 37.9 | 68.6 ± 14.9 | −91.9 ± 32.7 | 0.02 |
| Insulin AUC | 390.8 ± 73.5 | 233.2 ± 38.8 | −157.6 ± 58.4 | 0.03 |
| HOMA-IR | 5.45 ± 0.69 | 3.69 ± 0.54 | −1.76 ± 0.73 | 0.04 |
| Serum lipids (n = 10) | ||||
| Total cholesterol (mg/dl) | 165 ± 11 | 153 ± 12 | −11.9 ± 6.3 | 0.09 |
| TG (mg/dl) | 228 ± 37 | 175 ± 25 | −52.6 ± 23.1 | 0.049 |
| HDL-cholesterol (mg/dl) | 32 ± 3.4 | 32 ± 3.5 | −0.5 ± 2.4 | 0.85 |
| LDL-cholesterol (mg/dl) | 87 ± 10 | 86 ± 11 | −0.93 ± 5.1 | 0.85 |
| Non-HDL-cholesterol (mg/dl) | 133 ± 11 | 122 ± 11 | −11.5 ± 5.4 | 0.06 |
| Fasting FFA (mmol/liter) | 0.48 ± 0.07 | 0.42 ± 0.05 | −0.05 ± 0.03 | 0.14 |
| DEXA scan (n = 10) | ||||
| Weight (kg) | 85 ± 2.6 | 84 ± 2.7 | −0.9 ± 0.8 | 0.28 |
| Lean body mass (kg) | 57.1 ± 2.7 | 58.1 ± 2.7 | 1.0 ± 0.9 | 0.02 |
| Total body fat (kg) | 24.1 ± 2.1 | 22.4 ± 2.1 | −1.7 ± 0.7 | 0.045 |
| Truncal fat (kg) | 16.3 ± 1.0 | 15.3 ± 1.1 | −1.1 ± 0.4 | 0.04 |
| Appendicular fat (kg) | 6.7 ± 1.1 | 6.2 ± 1.1 | −0.5 ± 0.3 | 0.20 |
| CT scan (n = 10) | ||||
| VAT (cm2) | 327 ± 30 | 323 ± 35 | −4 ± 19 | 0.80 |
| SAT (cm2) | 144 ± 30 | 138 ± 27 | −3 ± 4 | 0.30 |
| EGP (n = 9) | ||||
| Fasting EGP (mg/kg · min) | 2.03 ± 0.09 | 2.21 ± 0.09 | 0.18 ± 0.05 | 0.006 |
| Hyperinsulinemic EGP (mg/kg · min) | 0.35 ± 0.05 | 0.52 ± 0.06 | 0.17 ± 0.05 | 0.01 |
| EGP suppression by insulin (%) | 83.2 ± 2.1 | 76.6 ± 2.8 | −6.6 ± 2.7 | 0.04 |
| GNG (n = 9) | ||||
| Fasting GNG (mg/kg/min) | 0.53 ± 0.04 | 0.65 ± 0.01 | 0.12 ± 0.04 | 0.01 |
| Hyperinsulinemic GNG (mg/kg/min) | 0.03 ± 0.01 | 0.04 ± 0.01 | 0.01 ± 0.01 | 0.29 |
| GNG suppression by insulin (%) | 94.0 ± 1.1 | 93.6 ± 0.9 | −0.4 ± 0.9 | 0.69 |
| Glycogenolysisa (n = 9) | ||||
| Fasting (mg/kg · min) | 1.50 ± 0.06 | 1.56 ± 0.09 | 0.06 ± 0.06 | 0.33 |
| Hyperinsulinemic (mg/kg · min) | 0.32 ± 0.05 | 0.48 ± 0.05 | 0.16 ± 0.05 | 0.01 |
| Suppression by insulin (%) | 79.4 ± 2.6 | 68.6 ± 4.3 | −10.7 ± 4.3 | 0.04 |
| De novo lipogenesis (n = 10) | ||||
| Fasting DNL (%) | 8.64 ± 1.34 | 6.07 ± 1.05 | −2.57 ± 1.2 | 0.06 |
| Postprandial DNL (%) | 12.68 ± 2.12 | 9.83 ± 1.98 | −2.85 ± 1.7 | 0.14 |
| IGFBPs (n = 10) | ||||
| IGFBP-1 (ng/mL) | 8.7 ± 1.8 | 9.0 ± 2.1 | 0.3 ± 1.9 | 0.88 |
| IGFBP-2 (ng/mL) | 409 ± 61 | 727 ± 129 | 318 ± 91 | 0.007 |
| IGFBP-3 (ng/mL) | 3865 ± 336 | 4082 ± 341 | 217 ± 139 | 0.15 |
| Other hormones | ||||
| Cortisol (μg/ml) (n = 10) | 9.7 ± 1.9 | 13.4 ± 2.6 | 3.7 ± 2.0 | 0.09 |
| GH (ng/ml)b | 0.23 ± 0.96 | 0.075 ± 0.018 | −0.16 ± 0.09 | N/A |
Data are mean ± sem, and P values are by Student’s t test. Values in bold are statistically significant (P < 0.05). The mean and sem values were calculated by setting the undetectable values at 0.05 ng/ml. Statistical analysis was not performed due to the few subjects with detectable values (n = 2) at month 3. LDL, Low-density lipoprotein.
a
Glycogenolysis is a calculated value (EGP − GNG).
b
GH levels were undetectable (i.e. <0.05 ng/ml) in 50% of subjects at baseline and 80% of subjects at month 3.