背景:慢性炎症有助于异丙肾上腺素(ISO)诱导的心力衰竭(HF)的进展。胱天蛋白酶相关募集结构域(CARD)家族是先天免疫中炎症起始的关键蛋白。尽管如此,CARD在ISO驱动的心脏重塑中的相关性研究甚少。
方法:本研究使用Card9-/-小鼠和具有Card9-/-或Otud1-/-骨髓来源细胞的重构C57BL/6小鼠。在原代巨噬细胞中进行了机制研究,心肌细胞,成纤维细胞和HEK-293T细胞。
结果:这里,我们证明CARD9在输注ISO的小鼠心脏中显著上调。无论是全身CARD9敲除或髓样特异性CARD9缺失抑制ISO驱动的小鼠心脏炎症,重塑和功能障碍。巨噬细胞中的CARD9缺乏可预防ISO诱导的炎症,并减轻心肌细胞和成纤维细胞的重塑变化。机械上,我们发现ISO通过上调巨噬细胞中卵巢肿瘤去泛素酶1(OTUD1)增强CARD9的活性。我们进一步证明了OTUD1直接与CARD9结合,然后从CARD9中去除K33连接的泛素,以促进CARD9-BCL10-MALT1(CBM)复合物的组装,不影响CARD9稳定性。ISO激活的CBM复合物导致NF-κB激活和基于巨噬细胞的炎症基因过度产生,然后增强心肌细胞肥大和成纤维细胞纤维化,分别。髓系特异性OTUD1缺失也减弱了ISO诱导的小鼠心脏炎症和重塑。
结论:这些结果表明,OTUD1-CARD9轴在ISO攻击的巨噬细胞中是一种新的促炎信号,靶向该轴对ISO诱导的HF具有保护作用。
结论:慢性ISO给药小鼠心脏组织中巨噬细胞CARD9升高。全身CARD9敲除或髓样特异性CARD9缺陷可保护小鼠免受ISO诱导的炎性心脏重塑。ISO促进CBM复合物的组装,然后通过OTUD1介导的去泛素化修饰激活巨噬细胞中的NF-κB信号传导。骨髓细胞中OTUD1缺失保护小鼠心脏免受ISO诱导的损伤。
BACKGROUND: Chronic inflammation contributes to the progression of isoproterenol (ISO)-induced heart failure (HF). Caspase-associated recruitment domain (CARD) families are crucial proteins for initiation of inflammation in innate immunity. Nonetheless, the relevance of CARDs in ISO-driven cardiac remodelling is little explored.
METHODS: This study utilized Card9-/- mice and reconstituted C57BL/6 mice with either Card9-/- or Otud1-/- marrow-derived cells. Mechanistic studies were conducted in primary macrophages, cardiomyocytes, fibroblasts and HEK-293T cells.
RESULTS: Here, we demonstrated that CARD9 was substantially upregulated in murine hearts infused with ISO. Either whole-body CARD9 knockout or myeloid-specific CARD9 deletion inhibited ISO-driven murine cardiac inflammation, remodelling and dysfunction. CARD9 deficiency in macrophages prevented ISO-induced inflammation and alleviated remodelling changes in cardiomyocytes and fibroblasts. Mechanistically, we found that ISO enhances the activity of CARD9 by upregulating ovarian tumour deubiquitinase 1 (OTUD1) in macrophages. We further demonstrated that OTUD1 directly binds to the CARD9 and then removes the K33-linked ubiquitin from CARD9 to promote the assembly of the CARD9-BCL10-MALT1 (CBM) complex, without affecting CARD9 stability. The ISO-activated CBM complex results in NF-κB activation and macrophage-based inflammatory gene overproduction, which then enhances cardiomyocyte hypertrophy and fibroblast fibrosis, respectively. Myeloid-specific OTUD1 deletion also attenuated ISO-induced murine cardiac inflammation and remodelling.
CONCLUSIONS: These results suggested that the OTUD1-CARD9 axis is a new pro-inflammatory signal in ISO-challenged macrophages and targeting this axis has a protective effect against ISO-induced HF.
CONCLUSIONS: Macrophage CARD9 was elevated in heart tissues of mice under chronic ISO administration. Either whole-body CARD9 knockout or myeloid-specific CARD9 deficiency protected mice from ISO-induced inflammatory heart remodeling. ISO promoted the assembly of CBM complex and then activated NF-κB signaling in macrophages through OTUD1-mediated deubiquitinating modification. OTUD1 deletion in myeloid cells protected hearts from ISO-induced injuries in mice.