2. Academic Validation
  3. Baicalin inhibits PANoptosis by blocking mitochondrial Z-DNA formation and ZBP1-PANoptosome assembly in macrophages

Baicalin inhibits PANoptosis by blocking mitochondrial Z-DNA formation and ZBP1-PANoptosome assembly in macrophages

  • Acta Pharmacol Sin. 2024 Sep 2. doi: 10.1038/s41401-024-01376-8.
Yi-Ping You # 1 2 3 4 5,  Liang Yan # 2 3 5,  Hua-Yu Ke # 1 2 5,  Ya-Ping Li 1 2,  Zi-Jian Shi 6,  Zhi-Ya Zhou 2,  Hai-Yan Yang 2,  Tao Yuan 2 5,  Ying-Qing Gan 2,  Na Lu 2,  Li-Hui Xu 1 2 5,  Bo Hu 7,  Dong-Yun Ou-Yang 8 9,  Qing-Bing Zha 10 11 12,  Xian-Hui He 13 14 15 16 17
Affiliations

Affiliations

  • 1 State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, Guangzhou, 510632, China.
  • 2 Department of Immunology and Microbiology, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China.
  • 3 Center of Reproductive Medicine, The First Affiliated Hospital of Jinan University, Guangzhou, 510632, China.
  • 4 Department of Clinical Laboratory, The Fifth Affiliated Hospital (Heyuan Shenhe People's Hospital), Jinan University, Heyuan, 517000, China.
  • 5 Guangdong Provincial Key Laboratory of Spine and Spinal Cord Reconstruction, The Fifth Affiliated Hospital (Heyuan Shenhe People's Hospital), Jinan University, Heyuan, 517000, China.
  • 6 Department of Fetal Medicine, The First Affiliated Hospital of Jinan University, Guangzhou, 510632, China.
  • 7 Department of Nephrology, The First Affiliated Hospital of Jinan University, Guangzhou, 510632, China.
  • 8 State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, Guangzhou, 510632, China. dongyun1967@aliyun.com.
  • 9 Department of Immunology and Microbiology, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China. dongyun1967@aliyun.com.
  • 10 Center of Reproductive Medicine, The First Affiliated Hospital of Jinan University, Guangzhou, 510632, China. zhaqingbb@sina.com.
  • 11 Department of Clinical Laboratory, The Fifth Affiliated Hospital (Heyuan Shenhe People's Hospital), Jinan University, Heyuan, 517000, China. zhaqingbb@sina.com.
  • 12 Guangdong Provincial Key Laboratory of Spine and Spinal Cord Reconstruction, The Fifth Affiliated Hospital (Heyuan Shenhe People's Hospital), Jinan University, Heyuan, 517000, China. zhaqingbb@sina.com.
  • 13 State Key Laboratory of Bioactive Molecules and Druggability Assessment, Jinan University, Guangzhou, 510632, China. thexh@jnu.edu.cn.
  • 14 Department of Immunology and Microbiology, College of Life Science and Technology, Jinan University, Guangzhou, 510632, China. thexh@jnu.edu.cn.
  • 15 Center of Reproductive Medicine, The First Affiliated Hospital of Jinan University, Guangzhou, 510632, China. thexh@jnu.edu.cn.
  • 16 Department of Clinical Laboratory, The Fifth Affiliated Hospital (Heyuan Shenhe People's Hospital), Jinan University, Heyuan, 517000, China. thexh@jnu.edu.cn.
  • 17 Guangdong Provincial Key Laboratory of Spine and Spinal Cord Reconstruction, The Fifth Affiliated Hospital (Heyuan Shenhe People's Hospital), Jinan University, Heyuan, 517000, China. thexh@jnu.edu.cn.
  • # Contributed equally.
PMID: 39223367 DOI: 10.1038/s41401-024-01376-8
Abstract

PANoptosis is an emerging form of regulated cell death (RCD) characterized by simultaneous activation of pyroptotic, apoptotic, and necroptotic signaling that not only participates in pathologies of inflammatory diseases but also has a critical role against pathogenic infections. Targeting PANoptosis represents a promising therapeutic strategy for related inflammatory diseases, but identification of inhibitors for PANoptosis remains an unmet demand. Baicalin () is an active flavonoid isolated from Scutellaria baicalensis Georgi (Huangqin), a traditional Chinese medicinal herb used for heat-clearing and detoxifying. Numerous studies suggest that baicalin possesses inhibitory activities on various forms of RCD including Apoptosis/secondary necrosis, Pyroptosis, and Necroptosis, thereby mitigating inflammatory responses. In this study we investigated the effects of baicalin on PANoptosis in macrophage cellular models. Primary macrophages (BMDMs) or J774A.1 macrophage cells were treated with 5Z-7-oxozeaenol (OXO, an inhibitor for TAK1) in combination with TNF-α or LPS. We showed that OXO plus TNF-α or LPS induced robust lytic cell death, which was dose-dependently inhibited by baicalin (50-200 μM). We demonstrated that PANoptosis induction was accompanied by overt mitochondrial injury, mitochondrial DNA (mtDNA) release and Z-DNA formation. Z-DNA was formed from cytosolic oxidized mtDNA. Both oxidized mtDNA and mitochondrial Z-DNA puncta were co-localized with the PANoptosome (including ZBP1, RIPK3, ASC, and Caspase-8), a platform for mediating PANoptosis. Intriguingly, baicalin not only prevented mitochondrial injury but also blocked mtDNA release, Z-DNA formation and PANoptosome assembly. Knockdown of ZBP1 markedly decreased PANoptotic cell death. In a mouse model of hemophagocytic lymphohistiocytosis (HLH), administration of baicalin (200 mg/kg, i.g., for 4 times) significantly mitigated lung and liver injury and reduced levels of serum TNF-α and IFN-γ, concomitant with decreased levels of PANoptosis hallmarks in these organs. Baicalin also abrogated the hallmarks of PANoptosis in liver-resident macrophages (Kupffer cells) in HLH mice. Collectively, our results demonstrate that baicalin inhibits PANoptosis in macrophages by blocking mitochondrial Z-DNA formation and ZBP1-PANoptosome assembly, thus conferring protection against inflammatory diseases. PANoptosis is a form of regulated cell death displaying simultaneous activation of pyroptotic, apoptotic, and necroptotic signaling. This study shows that induction of PANoptosis is linked to mitochondrial dysfunction and mitochondrial Z-DNA formation. Baicalin inhibits PANoptosis in macrophages in vitro via blocking mitochondrial dysfunction and the mitochondrial Z-DNA formation and thereby impeding the assembly of ZBP1-associated PANoptosome. In a mouse model of hemophagocytic lymphohistiocytosis (HLH), baicalin inhibits the activation of PANoptotic signaling in liver-resident macrophages (Kupffer cells) in vivo, thus mitigating systemic inflammation and multiple organ injury in mice.

Keywords

PANoptosis; ZBP1; baicalin; hemophagocytic lymphohistiocytosis; macrophages; mitochondrial Z-DNA.

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