Activation of adenosine-receptor-enhanced iNOS mRNA expression by gingival epithelial cells.
A series of reports has revealed that adenosine has a plethora of biological actions toward a large variety of cells. In this study, we investigated the influence of adenosine receptor activation on iNOS mRNA expression in human gingival epithelial cells (HGEC) and SV-40-transformed HGEC. HGEC expressed adenosine receptor subtypes A1, A2a, and A2b, but not A3 mRNA. Ligation of adenosine receptors by a receptor agonist, 2-chloroadenosine (2CADO), enhanced iNOS mRNA expression by both HGEC and transformed HGEC. In addition, the adenosine receptor agonist enhanced the production of NO(2)(-)/NO(3)(-), NO-derived stable end-products. An enhanced expression of iNOS mRNA and NO(2)(-)/NO(3)(-) was also observed when SV40-transformed HGEC were stimulated with CPA or CGS21680, A1- or A2a-selective adenosine receptor agonists, respectively. These results provide new evidence for the possible involvement of adenosine in the regulation of inflammatory responses by HGEC in periodontal tissues.
Murakami
S
S
Department of Periodontology, Division of Oral Biology and Disease Control, Osaka University Graduate School of Dentistry, 1-8 Yamadaoka, Suita, Japan. ipshinya@dent.osaka-u.ac.jp
Yoshimura
N
N
Koide
H
H
Watanabe
J
J
Takedachi
M
M
Terakura
M
M
Yanagita
M
M
Hashikawa
T
T
Saho
T
T
Shimabukuro
Y
Y
Okada
H
H
D000241:Adenosine / Q000502:physiology*; D002461:Cell Line, Transformed; D002478:Cells, Cultured; D004789:Enzyme Activation; D004847:Epithelial Cells / Q000201:enzymology*; D015971:Gene Expression Regulation, Enzymologic; D005881:Gingiva / Q000166:cytology / Q000201:enzymology*; D006801:Humans; D009566:Nitrates / Q000032:analysis; D019001:Nitric Oxide Synthase / Q000096:biosynthesis*; D052247:Nitric Oxide Synthase Type II; D009573:Nitrites / Q000032:analysis; D058906:Purinergic P1 Receptor Agonists; D012333:RNA, Messenger / Q000096:biosynthesis; D018047:Receptors, Purinergic P1 / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013539:Simian virus 40
D009566:Nitrates; D009573:Nitrites; D058906:Purinergic P1 Receptor Agonists; D012333:RNA, Messenger; D018047:Receptors, Purinergic P1; C496319:NOS2 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; D000241:Adenosine