Anti-Inflammatory Effects and Mechanisms of Action of Coussaric and Betulinic Acids Isolated from Diospyros kaki in Lipopolysaccharide-Stimulated RAW 264.7 Macrophages.
Diospyros kaki Thunb. is widely distributed in East Asian countries, its leaves being mainly used for making tea. In this study, coussaric acid (CA) and betulinic acid (BA), both triterpenoid compounds, were obtained from D. kaki leaf extracts through bioassay-guided isolation. CA and BA showed anti-inflammatory effects via inhibition of the nuclear factor-κB (NF-κB) pathway, providing important information on their anti-inflammatory mechanism. Furthermore, they markedly inhibited nitric oxide (NO) and prostaglandin E₂ (PGE₂) production in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages, and suppressed tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) levels. Furthermore, they decreased protein expression of inducible nitric oxide synthase and cyclooxygenase-2. Pre-treatment with CA and BA inhibited LPS-induced NF-κB. We further examined the effects of CA and BA on heme oxygenase (HO)-1 expression in RAW 264.7 macrophages: BA induced HO-1 protein expression in a dose-dependent manner, while CA had no effect. We also investigated whether BA treatment induced nuclear translocation of Nrf2. BA inhibited LPS-induced NF-κB-binding activity, as well as pro-inflammatory mediator and cytokine production (e.g., NO, PGE₂, TNF-α, IL-1β, IL-6), by partial reversal of this effect by SnPP, an inhibitor of HO-1. These findings further elucidate the anti-inflammatory mechanism of CA and BA isolated from D. kaki.
Research Institute of Pharmaceutical Sciences, Keimyung University, 1095 Dalgubeol-Daero, Daegu 42601, Korea. kskim@kmu.ac.kr.
Kyoung-Su
KS
Kim
College of Pharmacy, Chosun University, Dong-Gu, Gwangju 61452, Korea. dslee2771@chosun.ac.kr.
Dong-Sung
DS
Lee
Institute of Pharmaceutical Research and Development, College of Pharmacy, Wonkwang University, Iksan 54538, Korea. kimman07@hanmail.net.
Dong-Cheol
DC
Kim
Institute of Pharmaceutical Research and Development, College of Pharmacy, Wonkwang University, Iksan 54538, Korea. ycs1991@naver.com.
Chi-Su
CS
Yoon
Institute of Pharmaceutical Research and Development, College of Pharmacy, Wonkwang University, Iksan 54538, Korea. rabis815@naver.com.
Wonmin
W
Ko
Institute of Pharmaceutical Research and Development, College of Pharmacy, Wonkwang University, Iksan 54538, Korea. hoh@wku.ac.kr.
Hyuncheol
H
Oh
Institute of Pharmaceutical Research and Development, College of Pharmacy, Wonkwang University, Iksan 54538, Korea. yckim@wku.ac.kr.
Youn-Chul
YC
Kim
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D051546:Cyclooxygenase 2 / Q000378:metabolism; D015232:Dinoprostone / Q000096:biosynthesis; D029788:Diospyros / Q000737:chemistry*; D051547:Heme Oxygenase-1 / Q000037:antagonists & inhibitors* / Q000378:metabolism; D008070:Lipopolysaccharides / Q000633:toxicity*; D008565:Membrane Proteins / Q000037:antagonists & inhibitors* / Q000378:metabolism; D051379:Mice; D015846:Monokines / Q000096:biosynthesis; D016328:NF-kappa B / Q000378:metabolism; D009569:Nitric Oxide / Q000096:biosynthesis; D053978:Pentacyclic Triterpenes; D000067996:RAW 264.7 Cells; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D000094062:Betulinic Acid
D000893:Anti-Inflammatory Agents; D008070:Lipopolysaccharides; D008565:Membrane Proteins; D015846:Monokines; D016328:NF-kappa B; D053978:Pentacyclic Triterpenes; D014315:Triterpenes; D009569:Nitric Oxide; D051547:Heme Oxygenase-1; C496542:Hmox1 protein, mouse; C077623:Ptgs2 protein, mouse; D051546:Cyclooxygenase 2; D015232:Dinoprostone; D000094062:Betulinic Acid
Diospyros kaki Thunb.; anti-inflammation; betulinic acid (BA); coussaric acid (CA); heme oxygenase-1; nuclear factor-kappa B