Objective: In systemic lupus erythematosus (SLE), inadequate removal of apoptotic cells may lead to challenge of the immune system with immunogenic self antigens that have been modified during apoptosis. We undertook this study to evaluate whether apoptosis-induced histone modifications are targets for the immune system in SLE.
Methods: The epitope of KM-2, a monoclonal antihistone autoantibody derived from a lupus mouse, was mapped by random peptide phage display. The reactivity of KM-2 and plasma with (acetylated) histone H4 (H4) peptides and with nonapoptotic, apoptotic, and hyperacetylated histones was determined by immunofluorescence staining, enzyme-linked immunosorbent assay, and Western blotting.
Results: KM-2 recognized apoptosis-induced acetylation of H4 at lysines 8, 12, and 16. The majority of plasma samples from SLE patients and lupus mice showed higher reactivity with triacetylated H4 peptide (residues 1-22) and with hyperacetylated and apoptotic histones than with nonacetylated H4 peptide and normal histones. Importantly, administration of triacetylated H4 peptide to lupus-prone mice before disease onset accelerated the disease by enhancing mortality and aggravating proteinuria, skin lesions, and glomerular IgG deposition, while the nonacetylated H4 peptide had no pathogenic effect. The delayed-type hypersensitivity response in lupus mice against the triacetylated H4 peptide was higher than that against the nonacetylated H4 peptide. Bone marrow-derived dendritic cells (DCs) cultured in the presence of hyperacetylated nucleosomes showed increased expression/production of CD40, CD86, interleukin-6 (IL-6), and tumor necrosis factor alpha compared with DCs cultured in the presence of normal nucleosomes. Finally, DCs cultured in the presence of hyperacetylated nucleosomes were able to activate syngeneic T cells, because IL-2 production increased.
Conclusion: Apoptosis-induced acetylation of nucleosomes may represent an important driving force in the development of lupus.
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http://dx.doi.org/10.1002/art.22646 | DOI Listing |
Int Immunopharmacol
January 2025
Department of Obstetrics and Gynecology, First Hospital of Lanzhou University, Gansu Provincial Clinical Research Center for Gynecological Oncology, Lanzhou, 730000 Gansu, China; Department of Obstetrics and Gynecology, First Hospital of Lanzhou University, Lanzhou, 730000 Gansu, China. Electronic address:
Endometrial cancer (EC) is a common gynecological cancer, characterized by increasing incidence and mortality rates. Maackiain (MA), a natural flavonoid compound, has multiple biological activities, but little is known about how it affects EC cells. In the present study, CCK-8, EdU, colony formation, and flow cytometry assays were used to evaluate the effects of MA on EC cell proliferation, apoptosis, and reactive oxygen species (ROS) levels.
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Shenzhen University Diabetes Institute, Shenzhen Key Laboratory of Metabolism and Cardiovascular Homeostasis, School of Medicine, Shenzhen University, Shenzhen 518060, China.
Roux-en-Y gastric bypass (RYGB) has been shown to inhibit β-cell apoptosis, but the underlying mechanisms are not yet fully understood. Cytochrome c oxidase subunit 6A2 (COX6A2) is expressed in β-cells. Here, we sought to investigate the role of COX6A2 in β-cell apoptosis, especially following RYGB.
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Molecular Genetics Team of the Institute of Translational Medicine, Zhuhai People's Hospital (Zhuhai Clinical Medical College of Jinan University), Zhuhai 519000, China.
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June 2024
Municipal Hospital Affiliated to Taizhou University, Taizhou, Jiaojiang 318000, Zhejiang, China. Electronic address:
Background: Sorafenib (Sora), a multi-target tyrosine kinase inhibitor, is widely recognized as a standard chemotherapy treatment for advanced hepatocellular carcinoma (HCC). However, drug resistance mechanisms hinder its anticancer efficacy. Derived from Withania somnifera, Withaferin A (WA) exhibits remarkable anti-tumor properties as a natural bioactive compound.
View Article and Find Full Text PDFNaunyn Schmiedebergs Arch Pharmacol
September 2024
School of Pharmacy, National Taiwan University, No. 33, Linsen S. Rd., Zhongzheng Dist, Taipei, 100, Taiwan.
The treatment of non-small cell lung cancer (NSCLC) is known as a significant level of unmet medical need in spite of the progress in targeted therapy and personalized therapy. Overexpression of the Na/K-ATPase contributes to NSCLC progression, suggesting its potentiality in antineoplastic approaches. Epi-reevesioside F, purified from Reevesia formosana, showed potent anti-NSCLC activity through inhibiting the Na/K-ATPase, leading to internalization of α1- and α3-subunits in Na/K-ATPase and suppression of Akt-independent mTOR-p70S6K-4EBP1 axis.
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