Potential chemoprevention of LPS-stimulated nitric oxide and prostaglandin E₂ production by α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranosyl-3-indolecarbonate in BV2 microglial cells through suppression of the ROS/PI3K/Akt/NF-κB pathway.
α-l-Rhamnopyranosyl-(1→6)-β-d-glucopyranosyl-3-indolecarbonate (RG3I) is a chemical constituent isolated from the commonly used Asian traditional medicinal plant, Clematis mandshurica; however, no studies have been reported on its anti-inflammatory properties. In the present study, we found that RG3I attenuates the lipopolysaccharide (LPS)-induced DNA-binding activity of nuclear factor-κB (NF-κB) via the dephosphorylation of PI3K/Akt in BV2 microglial cells, leading to a suppression of nitric oxide (NO) and prostaglandin E2 (PGE2) production, along with that of their regulatory genes, inducible NO synthase (iNOS) and cyclooxygenase-2 (Cox-2). Further, the PI3K/Akt inhibitor, LY294002 diminished the expression of LPS-stimulated iNOS and COX-2 genes by suppressing NF-κB activity. Moreover, RG3I significantly inhibited LPS-induced reactive oxygen species (ROS) generation similar to the ROS inhibitors, N-acetylcysteine (NAC) and glutathione (GSH). Notably, NAC and GSH abolished the LPS-induced expression of iNOS and Cox-2 in BV2 microglial cells by inhibiting NF-κB activity. Taken together, our data indicate that RG3I suppresses the production of proinflammatory mediators such as NO and PGE2 as well as their regulatory genes in LPS-stimulated BV2 microglial cells by inhibiting the PI3K/Akt- and ROS-dependent NF-κB signaling pathway, suggesting that RG3I may be a good candidate to regulate LPS-induced inflammatory response.
Laboratory of Immunobiology, Department of Marine Life Sciences, Jeju National University, Ara-1 dong, Jeju 690-756, Republic of Korea.
Matharage Gayani
MG
Dilshara
Division of Wood Chemistry & Microbiology, Department of Forest Products, Korea Forest Research Institute, 57 Hoegiro, Dongdaemun-gu, Seoul 130-712, Republic of Korea.
Kyoung-Tae
KT
Lee
Department of Biochemistry, College of Oriental Medicine, Dong-Eui University, Busan 614-050, Republic of Korea.
Yung Hyun
YH
Choi
Department of Biology Education, Daegu University, Jillyang, Gyeongsan, Gyeongbuk 712-714, Republic of Korea.
Dong-Oh
DO
Moon
Division of Wood Chemistry & Microbiology, Department of Forest Products, Korea Forest Research Institute, 57 Hoegiro, Dongdaemun-gu, Seoul 130-712, Republic of Korea.
Hak-Ju
HJ
Lee
Department of Biology Education, Daegu University, Jillyang, Gyeongsan, Gyeongbuk 712-714, Republic of Korea.
Sung Gyu
SG
Yun
Laboratory of Immunobiology, Department of Marine Life Sciences, Jeju National University, Ara-1 dong, Jeju 690-756, Republic of Korea. Electronic address: immunkim@jejunu.ac.kr.
Gi-Young
GY
Kim
D000818:Animals; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D002460:Cell Line; D002852:Chromatography, Ion Exchange; D015232:Dinoprostone / Q000096:biosynthesis*; D004187:Disaccharides / Q000494:pharmacology*; D007211:Indoles / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D017628:Microglia / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D009569:Nitric Oxide / Q000096:biosynthesis*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects*
D016588:Anticarcinogenic Agents; D004187:Disaccharides; D007211:Indoles; D008070:Lipopolysaccharides; D016328:NF-kappa B; D017382:Reactive Oxygen Species; C000593045:rhamnopyranosyl-(1-6)-glucopyranosyl-3-indolecarbonate; D009569:Nitric Oxide; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D015232:Dinoprostone
Nitric oxide; Nuclear factor-κB; PI3K/Akt; Prostaglandin E(2); Reactive oxygen species; α-l-Rhamnopyranosyl-(1→6)-β-d-glucopyranosyl-3-indolecarbonate