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2026 Vol.39, Issue 4
Anti-Inflammatory Activity of the Ethyl Acetate Fraction of Auricularia nigricans against LPS-induced Inflammatory Responses in Macrophages through Modulation of MAPK/NF-κB and ROS/PI3K/Nrf2/HO-1 Signaling

MAPK/NF-κB 및 ROS/PI3K/Nrf2/HO-1 신호 조절을 통한 털목이버섯(Auricularia nigricans) 에틸아세테이트 분획물의 LPS 유도 대식세포 염증반응 억제 효과

So Jung Park1†
,
Kyoung Tae Lee2†
,
Jeong Won Choi3
,
Hyeok Jin Choi1
,
Gyeong Eun Im1
,
Bo Hee Seo1
,
Ha Eun Kim4
,
Youngki Park5
,
Jin Boo Jeong6
박 소정1†
,
이 경태2†
,
최 정원3
,
최 혁진1
,
임 경은1
,
서 보희1
,
김 하은4
,
박 영기5
,
정 진부6
1Graduate Student, Department of Forest Science, Gyeongkuk National University, Andong 36729, Korea
2Researcher, Department of Forest Bioresources, Division of Forest Microbiology, National Institute of Forest Science, Suwon 16631, Korea
3Post-doc, Department of Forest Science, Gyeongkuk National University, Andong 36729, Korea
4Undergraduate Student, Department of Forest Science, Gyeongkuk National University, Andong 36729, Korea
5Senior Researcher, Department of Forest Bioresources, Division of Forest Microbiology, National Institute of Forest Science, Suwon 16631, Korea
6Professor, Department of Forest Science, Gyeongkuk National University, Andong 36729, Korea
1국립경국대학교 산림과학과, 대학원생
2국립산림과학원 산림생명자원연구부, 연구사
3국립경국대학교 산림과학과, 박사후 연구원
4국립경국대학교 산림과학과, 학부생
5국립산림과학원 산림생명자원연구부, 연구관
6국립경국대학교 산림과학과, 교수
*Corresponding Author
†These authors contributed equally to this work.
1 August 2026. pp. 179-190
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Abstract

Auricularia nigricans is an edible and medicinal mushroom consumed in East Asia, but the anti-inflammatory mechanisms of its ethyl acetate fraction remain unclear. This study evaluated the anti-inflammatory effects of the ethyl acetate fraction of A. nigricans (AN-EA) in LPS-stimulated RAW264.7 macrophages. AN-EA dose-dependently reduced LPS-induced NO and PGE2 production without cytotoxicity. It also suppressed the LPS-induced expression of iNOS and COX-2 at both protein and mRNA levels. Mechanistic analysis showed that AN-EA inhibited the phosphorylation of MAPK-related proteins, including ERK1/2, p38, JNK, and ATF-2, as well as NF-κB p65. In addition, AN-EA activated the cytoprotective Nrf2/HO-1 pathway, increasing Nrf2 expression from 1 h and HO-1 expression from 6 h. LY294002 and NAC inhibited AN-EA-induced Nrf2 and HO-1 expression, while NAC also blocked AN-EA-mediated PI3K phosphorylation. These results suggest that AN-EA suppresses inflammatory responses by inhibiting MAPK/NF-κB signaling and activating the ROS-dependent PI3K/Nrf2/HO-1 pathway.

Keywords
Anti-inflammation
Auricularia heimuer
RAW264.7 macrophages
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Information
  • Publisher :The Plant Resources Society of Korea
  • Publisher(Ko) :한국자원식물학회
  • Journal Title :Korean Journal of Plant Resources
  • Journal Title(Ko) :한국자원식물학회지
  • Volume : 39
  • No :4
  • Pages :179-190
  • Received Date : 2026-05-11
  • Accepted Date : 2026-05-27
  • DOI :https://doi.org/10.7732/kjpr.2026.39.4.179
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