Insulin-like growth factor-1 cytokines cross-talk in type 1 diabetes mellitus: Relationship to microvascular complications and bone mineral density

Objective: This study was designed to investigate the association between inflammatory cytokines (IL-8, IL-6) and IGF-1 levels in relation to metabolic control, microvascular complications and bone mineral density (BMD) in a cohort of Egyptian adolescents with T1DM. Research design and methods: Sixty patients with T1DM (mean age was 14.67 +/- 1.53 years, mean disease duration was 6.87 +/- 1.25 years) and 40 controls participated in the study. Thirty-six patients (60%) had poor glycemic control (HbA1C measurements >= 8%) while the rest (n = 24%, 40%) had good glycemic control (HbA1C measurements <8%). Serum 1L-6, IL-8, and IGF-1 levels were measured. Whole body DXA scan were assessed. Total body and lumbar spine (L2-L4) bone mineral content (BMC, g) and bone area (BA, cm(2)) were measured by DXA scan, bone mineral density (BMD, g/cm(2)) was calculated by BMC/BA. Results: Patients with T1DM had higher IL-6 and IL-8 levels with lower IGF-1 than healthy controls (P < 0.001). Within the T1DM patients those with poor glycemic control had higher IL-6 and IL-8 as well as lower IGF-1 and total BMD than those with good glycemic control (P < 0.001 for all). IL-6 and IL-8 were negatively correlated with IGF-1 (P = 0.005 and 0.021, respectively). The peripheral neuropathy rate was also greater in T1DM patients with poor glycemic control (P = 0.02). Presence of nephropathy or retinopathy was not different (P = 0.69 and 0.50, respectively). Conclusion: High IL-6, IL-8 with low IGF-1 levels are found in adolescents with T1DM. It seems that poor glycemic control exacerbates inflammatory cytokines, increases peripheral neuropathy, and decreases bone mineral density. (C) 2012 Elsevier Ltd. All rights reserved.