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2025 Vol.38, Issue 6 Preview Page

Research Article

Immunostimulatory Effects of the Fruits of Sambucus racemosa subsp. pendula via TLR4-mediated ROS/JNK and NF-κB Signaling in RAW264.7 Macrophages
Gyeong Eun Im1†
,
Ji A Kim2†
,
Jeong Won Choi1
,
So Jung Park1
,
Hyeok Jin Choi1
,
Min Yeong Choi3
,
Jin Boo Jeong4
1Graduate Student, Department of Forest Science, Gyeongkuk National University, Andong 36729, Korea
2Senior Researcher, Forest Medicinal Resources Research Center, National Institute of Forest Science, Yeongju 36040, Korea
3Post-Master’s Researcher, Forest Medicinal Resources Research Center, National Institute of Forest Science, Yeongju 36040, Korea
4Professor, Department of Forest Science, Gyeongkuk National University, Andong 36729, Korea
*Corresponding Author
†These authors contributed equally to this work.
1 December 2025. pp. 665-677
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Abstract

This study investigated the immunostimulatory effects of SRF in RAW264.7 macrophages. SRF enhanced NO production, iNOS expression, cytokine secretion (IL-1β, IL-6, TNF-α), and phagocytic activity without affecting cell viability. Mechanistically, SRF-induced macrophage activation was abrogated by a TLR4 inhibitor but not by a TLR2 inhibitor, indicating TLR4 dependence. Furthermore, JNK and NF-κB signaling pathways were activated by SRF in a TLR4-dependent manner, as shown by inhibitor studies and phosphorylation analysis. SRF also increased intracellular ROS levels via TLR4, and ROS inhibition suppressed SRF-induced JNK and NF-κB activation and subsequent NO production. These findings suggest that SRF activates macrophages through the TLR4-ROS-JNK/NF-κB axis.

Keywords
Immunostimulation
Innate immune system
Macrophage activation
Sambucus racemosa subsp. pendula fruits
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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 : 38
  • No :6
  • Pages :665-677
  • Received Date : 2025-10-17
  • Accepted Date : 2025-10-20
  • DOI :https://doi.org/10.7732/kjpr.2025.38.6.665
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