Effect of neurotrophins on endothelial cells

POZNER RG; SCHATTNER M; LITWAK SA; GOMEZ RM; MAUGERI N; LAZZARI MA

Paris, Francia

Congreso; XVIIIth Congress. International Society for Thrombosis and Haemostasis; 2001

EFFECT OF NEUROTROPHINS ON ENDOTHELIAL CELLS. Pozner R., Schattner M, Litwak S, Gomez R, Maugeri N, Lazzari M. Department of Thrombosis and Hemostasis, National Academy of Medicine, CONICET. Department of Microbiology, Faculty of Medicine, University of Buenos Aires, CONICET. Buenos Aires, Argentina.   Clinical and experimental data suggest that abnormal availability of neurotrophins (NT) contributes to the pathogenesis of diabetic neuropathy (DN). NTs and their receptors are expressed in neurons and other cells including endothelial cells (EC). Two phase III clinical trials using Nerve Growth Factor-b (NGF) for the treatment of DN have been completed with encouraging results. Since alterations in EC function play a central role in the pathogenesis of DN, we studied the effect of NGF, NT-3 and brain derived nerve factor (BDNF) on EC derived from human umbilical cords (HUVECs). The results were analyzed using the t test for paired data and they are expressed as the mean ± SEM of 6 independent experiments performed in duplicate.     NONE BDNF NT-3 NGF Basal vWF (ng/mL) 424±42 352±84 419±58 389±70 vWF + thrombin (ng/mL) 14±2 15±1 17±2 13±2 PGF1a + thrombin (ng/mL) 5±1 4±1 5±1 5±1 Basal VCAM-1 (AUF) 7±1 7±1 6±1 7±1 VCAM-1 + TNF (AUF) 32±8 38±9 36±7 38±10 Basal ICAM-1 (AUF) 16±3 18±3 15±4 11±3 ICAM-1 + TNF (AUF) 122±4 131±8 125±4 122±9 Treatment of HUVECs during 16 Hs. with NTs (0.01-100 ng/mL) did not significantly modify basal or thrombin induced release of von Willebrand factor (vWF) and 6-ceto-PGF1a, (PGF1a) (ELISA). The constitutive or TNF-a induced expression of VCAM-1 and ICAM-1 (flow cytometry) (arbitrary units of fluorescence (AUF)) was also not changed by NT treatment. When HUVECs were exposed to high glucose (HG) conditions (30 mM) during 24 Hs. there was an increased expression of ICAM-1 compared to control values (53±2* vs. 39±5) and this effect was enhanced by the incubation of EC with NGF 100 or 0.1 ng/mL (58±3* and 66±3** UAF, respectively, n=6, *p<0.05 vs. control, **p<0.05 vs. high glucose). Thrombin-induced ICAM-1 expression under HG concentration was higher than normal glucose (62±3 vs. 48±5 AUF, n=6, p<0.05). The incubation for 24 Hs. with NGF showed no change in thrombin-induced ICAM-1 expression but in HG medium, NGF (0.1 ng/mL) did potentiate ICAM-1 expression (66±3, n=6, p<0.05). These results suggest that NTs do not modulate functional responses of normal endothelium but at least NGF seems to alter integrin expression under HG conditions.