Histamine modulates reactive oxygen species (ROS) production through H1 and H2 membrane receptors.

MEDINA VANINA; CRICCO GRACIELA; GARBARINO GLORIA; NUÑEZ MARIEL; MARTIN GABRIELA; COCCA CLAUDIA; BERGOC ROSA; HORR BIANCA; DIEL FRIDHELM; RIVERA ELENA

Noviembre 4-6, 2004, Weimar, Alemania.

Congreso; 8th Meeting of the Signal Transduction Society.; 2004

Histamine modulates reactive oxygen species (ROS) production through H1 and H2 membrane receptors. The role of histamine (HA) on growth of normal cancer cells has been extensively investigated the last years and it has been clearly established that HA regulates cell growth of different cell lines derived from human neoplasias. In the present work we investigated the capacity of HA to modulate the intracellular levels of ROS and the receptors involved in this response. We studied the action of Ha on different normal (HBL-100) and malignant cells (MDA MB-231, WM 35). The levels if intracellular ROS H2O2 and O2-, we assessed by flow cytometric analysis employing the specific fluorescent dyes DCFH-DA (dichlorodihydro fluorescein diacetate) and HE (dihydroethidium) respectively. The activity of the antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT) was evaluated in cell extracts by spectrophotometric techniques.  Cell proliferation was determined by the clonogenic assay. Cells were treated with HA (10 nM to 10 uM), 10 uM of Mepyramine (H1 receptor antagonist), 2-(3Trifluormethyl)phenyl)histamine (H1 receptor agonist), famotidine (H2 receptor antagonist) and Dimaprit (H2 receptor agonist). Ha treatment significantly modified the activity of SOD and CAT in the different cell lines. Doses of HA below 100 nM reduced moderately the proliferation of HBL-100 non-tumorigenic breast epithelial cells. Proliferation was not modified after treatment with 10uM of HA. In WM35 melanoma cells, HA via H2 receptors increased cAMP levels (ED50 1 uM) inducing cell proliferation, while at higher doses (10 uM) and via H1 receptor, HA inhibited growth. Results obtained from MDA MB-231 breast carcinoma cells indicated that HA via H2 receptors increased cAMP levels (ED50 0.40 uM) producing a significant inhibition on cell proliferation. On the other hand, HA at doses below 100 nM  and via H1 receptor, increased cell proliferation. In both malignant cell types, H2O2 levels were inversely correlated with cell proliferation. From these data we conclude that HA can modulate cell proliferation via H1 and H2 receptors in different cell lines. Thid effect is exerted in part by the modulation of the activity of antioxidant enzymes an ROS production.