Endothelial dysfunction in children and adolescents with type 1 diabetes mellitus and its role in the development of diabetic peripheral polyneuropathy

Aim. To measure endothelial factors (nitric oxide (NOx) metabolites, endothelin-1 (ET-1), and basic fibroblast growth factor (bFGF)) in children and adolescents with diabetes mellitus (DM) during development of diabetic peripheral polyneuropathy (DPNP). Materials and methods. A total of 130 children and adolescents with diabetes mellitus were examined. Duration of DM varied from 3 months to 14 years. The control group comprised 20 children and adolescents without DM or neurologic pathology. Subjective manifestations of DPNP were assessed based on the data of a standardized Neuropathy Symptom Score (NSS) questionnaire. Neuropathy Disability Score (NDS) questionnaire was used to monitor objective changes of DPNP. NOx metabolites were detected with Griess reagent (Aldrich Chemical Co, USA). Serum ET-1 and bFGF were measured using solid-phase immunoenzyme assay (DRG, USA) and CYTIMMINE (USA) kits respectively. Results. All children and adolescents with DM1 had lower NOx and bFGF levels than controls. ET-1 level in DM patients was 3.5 times that in controls. DM patients with DPNP had more pronounced endothelial dysfunction than DM patients without DPNP and control subjects. Patients with hyperproduction of NOx had DM for more than 10 years and their total NDS score was significantly higher than in two other groups. Conclusion. Endothelial dysfunction in children and adolescents with type 1 diabetes mellitus progresses with the development of DPNP. Depletion of endothelial functional reserve is responsible for the unfavourable course of DPNP.