Inhibitory effects of nicotinamide on intercellular adhesion molecule-1 expression on cultured human thyroid cells.
We investigated the effects of nicotinamide and 3-aminobenzamide (3-AB), inhibitors of poly (ADP ribose) synthetase, on phytohaemagglutinin (PHA)- or interferon-gamma (IFN-gamma)-induced intercellular adhesion molecule-1 (ICAM-1) expression on cultured thyroid cells from patients with Graves' disease. Primary cultured thyroid cells were incubated for 3 days with IFN-gamma (10-800 U/ml) or PHA (1-50 micrograms/ml) in the presence of nicotinamide, 3-AB, superoxide dismutase or catalase. The surface expression of ICAM-1 was measured by flow cytometry. Nicotinamide and 3-AB dose-dependently inhibited the induction of ICAM-1 expression by IFN-gamma or PHA on thyroid cells. Neither catalase nor superoxide dismutase, which are free-radical scavengers, inhibited the expression of ICAM-1 on thyroid cells. Our data suggest that the mechanism of the suppression of ICAM-1 expression on thyroid cells by nicotinamide is not likely to be due to the free radical scavenging. Further studies are indicated to elucidate whether the inhibition of ICAM-1 by these drugs may result in the suppression of autoimmune reaction in the thyroid gland.
Hiromatsu
Y
Y
Department of Medicine, Kurume University School of Medicine, Fukuoka, Japan.
Sato
M
M
Tanaka
K
K
Ishisaka
N
N
Kamachi
J
J
Nonaka
K
K
D015703:Antigens, CD / Q000187:drug effects; D015815:Cell Adhesion Molecules / Q000032:analysis / Q000187:drug effects*; D002478:Cells, Cultured; D004306:Dose-Response Relationship, Immunologic; D006111:Graves Disease / Q000276:immunology*; D006801:Humans; D018799:Intercellular Adhesion Molecule-1; D007371:Interferon-gamma / Q000276:immunology; D009536:Niacinamide / Q000627:therapeutic use*; D010835:Phytohemagglutinins / Q000276:immunology; D011994:Recombinant Proteins; D013961:Thyroid Gland / Q000276:immunology*
D015703:Antigens, CD; D015815:Cell Adhesion Molecules; D010835:Phytohemagglutinins; D011994:Recombinant Proteins; D018799:Intercellular Adhesion Molecule-1; D009536:Niacinamide; D007371:Interferon-gamma