Department of Rhinology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China.
Department of Rhinology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China.
Int Immunopharmacol. 2023 Aug;121:110450. doi: 10.1016/j.intimp.2023.110450. Epub 2023 Jun 19.
Macrophages are involved in the pathogenesis of allergic rhinitis (AR), but how these macrophages are polarized to M1 or M2 type is undetermined. Long non-coding RNA growth arrest specific transcript 5 (GAS5) is upregulated in exosomes isolated from nasal mucus of AR patients (AR-EXO) and aggravates nasal symptoms in AR mice. In the present study, we are aimed to elucidate the potential role of GAS5 in macrophage polarization during AR pathogenesis. An AR mice model was constructed. The potential function of GAS5 was evaluated by western blot, RNA immunoprecipitation (RIP), biotinylated RNA pull-down assay, co-immunoprecipitation (co-IP) assay, flow cytometry, enzyme-linked immunosorbent assay (ELISA) assay, and immunohistochemistry (IHC) staining. We found that GAS5 is upregulated in ovalbumin-treated human nasal epithelial cells RPMI 2650 (OVA-EXO) and nasal mucus of AR mice. OVA-EXO treatment or forced GAS5 expression promoted M1 macrophage polarization of peripheral blood monocytes (PB monocytes) and THP-1 macrophages in vitro. GAS5 overexpression aggravated the allergic nasal symptoms induced by OVA in AR mice and facilitated M1 macrophage polarization and allergic inflammation, while knockdown of GAS5 exhibited opposite effects in vivo. GAS5 activated NF-кB signaling via suppressing autophagy-dependent degradation of IKKα/β in macrophages. Furthermore, GAS5 acted as a scaffold to strengthen the interaction between mTORC1 and ULK1, thus impaired ULK1/ATG13-mediated autophagy via increasing mTORC1 activity. Finally, restored autophagy by ATG13 overexpression suppressed the effect of GAS5 on M1 macrophage polarization. In conclusion, these results suggested that exosomal transfer of GAS5 promoted M1 macrophage polarization via restraining mTORC1/ULK1/ATG13-mediated autophagy and subsequently activating NF-кB signaling in allergic rhinitis.
巨噬细胞参与变应性鼻炎（AR）的发病机制，但这些巨噬细胞如何极化为 M1 或 M2 型尚不清楚。长链非编码 RNA 生长停滞特异性转录物 5（GAS5）在 AR 患者鼻黏液中分离的外泌体（AR-EXO）中上调，并加重 AR 小鼠的鼻部症状。在本研究中，我们旨在阐明 GAS5 在 AR 发病机制中调节巨噬细胞极化的潜在作用。构建了 AR 小鼠模型。通过 Western blot、RNA 免疫沉淀（RIP）、生物素化 RNA 下拉测定、共免疫沉淀（co-IP）测定、流式细胞术、酶联免疫吸附测定（ELISA）测定和免疫组织化学（IHC）染色评估 GAS5 的潜在功能。我们发现 GAS5 在卵清蛋白处理的人鼻上皮细胞 RPMI 2650（OVA-EXO）和 AR 小鼠的鼻黏液中上调。OVA-EXO 处理或强制表达 GAS5 促进了体外外周血单核细胞（PB 单核细胞）和 THP-1 巨噬细胞的 M1 巨噬细胞极化。GAS5 过表达加重了 AR 小鼠中 OVA 诱导的过敏性鼻症状，并促进了 M1 巨噬细胞极化和过敏炎症，而体内 GAS5 的敲低则表现出相反的效果。GAS5 通过抑制巨噬细胞中 IKKα/β的自噬依赖性降解来激活 NF-κB 信号。此外，GAS5 作为一种支架，增强了 mTORC1 和 ULK1 之间的相互作用，从而通过增加 mTORC1 活性来破坏 ULK1/ATG13 介导的自噬。最后，通过 ATG13 过表达恢复自噬抑制了 GAS5 对 M1 巨噬细胞极化的影响。总之，这些结果表明，外泌体转移的 GAS5 通过抑制 mTORC1/ULK1/ATG13 介导的自噬来促进 M1 巨噬细胞极化，随后在变应性鼻炎中激活 NF-κB 信号。
