Induction of nitric oxide synthase by Oldenlandia diffusa in mouse peritoneal macrophages.
Oldenlandia diffusa (OD) has been used to treat malignant tumors. In this study using mouse peritoneal macrophages, we have examined the mechanism by which OD regulates nitric oxide (NO) production. When OD (1 mg/ml) was used in combination with 10 U/ml of recombinant interferon-gamma (rIFN-gamma), there was a marked cooperative induction of NO production (36.13+/-7.12 microM) by the Griess method (nitrite). Treatment of macrophages with rIFN-gamma plus OD (1 mg/ml) caused a significant increase in tumor necrosis factor-alpha (TNF-alpha) production (4.49+/-1.43 ng/ml) by enzyme-linked immunosorbent assay. The increased production of NO and TNF-alpha from rIFN-gamma-plus OD-stimulated cells was almost completely inhibited by pretreatment with 100 microM of pyrrolidine dithiocarbamate (PDTC), an inhibitor of nuclear factor kappa B (NF-kappaB). PDTC also inhibited phosphorylation of IkappaB in rIFN-gamma-plus OD-stimulated cells. These findings demonstrate that OD increases the production of NO and TNF-alpha by rIFN-gamma-primed macrophages and suggest that NF-kappaB plays a critical role in mediating these effects of OD.
Chung
Hwan-Suck
HS
Department of Oriental Pharmacy, College of Pharmacy, Wonkwang University, Iksan, Chonbuk, South Korea. hmkim@wonkwang.ac.kr
Jeong
Hyun-Ja
HJ
Hong
Seung-Heon
SH
Kim
Mi-Sun
MS
Kim
So-Jin
SJ
Song
Bong-Keun
BK
Jeong
In-Seok
IS
Lee
Eon-Jeong
EJ
Ahn
Jong-Woong
JW
Baek
Seung-Hwa
SH
Kim
Hyung-Min
HM
D000818:Animals; D004305:Dose-Response Relationship, Drug; D004790:Enzyme Induction / Q000187:drug effects / Q000502:physiology; D006801:Humans; D017737:Macrophages, Peritoneal / Q000187:drug effects / Q000201:enzymology*; D051379:Mice; D019001:Nitric Oxide Synthase / Q000096:biosynthesis*; D032067:Oldenlandia; D010936:Plant Extracts / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D010936:Plant Extracts; D019001:Nitric Oxide Synthase