Department of Respiratory Diseases, The Affiliated Huai'an Hospital of Xuzhou Medical University, Huai'an, Jiangsu, People's Republic of China.
Institute of Medicinal Biotechnology, Jiangsu College of Nursing, Huai'an, Jiangsu, People's Republic of China.
Int J Chron Obstruct Pulmon Dis. 2023 May 6;18:797-809. doi: 10.2147/COPD.S405757. eCollection 2023.
Corticosteroid insensitivity has become a major barrier in the treatment of chronic obstructive pulmonary disease (COPD). It is known that oxidative stress reduces the expression and activity of histone deacetylase (HDAC)-2 by activating phosphoinositide-3-kinase-δ(PI3Kδ)/Akt pathway, which is a common mechanism. The aim of this study was to investigate whether cryptotanshinone (CPT) can improve corticosteroid sensitivity and to investigate the molecular mechanisms by which this occurs.
Corticosteroid sensitivity in peripheral blood mononuclear cells (PBMCs) collected from COPD patients, or in human monocytic U937 monocytic cells exposed to cigarette smoke extract (CSE), was quantified as the dexamethasone concentration required to achieve 30% inhibition of tumor necrosis factor-α (TNFα)-induced interleukin 8 (IL-8) production in the presence or absence of cryptotanshinone. PI3K/Akt activity (measured as the relative ratio of phosphorylated Akt at Ser-473 to total Akt) and HDAC2 expression levels were determined by western blotting. HDAC activity was evaluated by a Fluo-Lys HDAC activity assay kit in U937 monocytic cells.
Both PBMCs in patients with COPD and U937 cells exposed to CSE were found to be insensitive to dexamethasone, accompanied by increased phosphorylated Akt (pAkt) and decreased HDAC2 protein expression. The pretreatment of cryptotanshinone restored their sensitivity to dexamethasone, and simultaneously downregulated the level of phosphorylated Akt and upregulated the level of HDAC2 protein. Pretreatment with cryptotanshinone or IC87114 reversed the decrease in HDAC activity in CSE-stimulated U937 cells.
Cryptotanshinone restores corticosteroid sensitivity induced by oxidative stress via inhibition of PI3Kδ and is a potential treatment for corticosteroid-insensitive diseases such as COPD.
皮质类固醇不敏感已成为慢性阻塞性肺疾病（COPD）治疗的主要障碍。已知氧化应激通过激活磷酸肌醇 3-激酶-δ（PI3Kδ）/ Akt 途径降低组蛋白去乙酰化酶（HDAC）-2 的表达和活性，这是一种常见的机制。本研究旨在探讨隐丹参酮（CPT）是否能提高皮质类固醇的敏感性，并探讨其发生的分子机制。
通过定量分析来自 COPD 患者外周血单个核细胞（PBMCs）或暴露于香烟烟雾提取物（CSE）的人单核细胞 U937 单核细胞中皮质类固醇的敏感性，来评估隐丹参酮是否能提高皮质类固醇的敏感性。在存在或不存在隐丹参酮的情况下，用地塞米松抑制肿瘤坏死因子-α（TNFα）诱导的白细胞介素 8（IL-8）产生的 30%所需的地塞米松浓度来定量分析。通过 Western blot 测定 PI3K/Akt 活性（以磷酸化 Akt 在 Ser-473 处与总 Akt 的相对比值表示）和 HDAC2 表达水平。通过 Fluo-Lys HDAC 活性测定试剂盒评估 U937 单核细胞中的 HDAC 活性。
COPD 患者的 PBMCs 和暴露于 CSE 的 U937 细胞均对地塞米松不敏感，同时伴有磷酸化 Akt（pAkt）增加和 HDAC2 蛋白表达减少。隐丹参酮预处理恢复了它们对地塞米松的敏感性，同时下调了磷酸化 Akt 的水平，上调了 HDAC2 蛋白的水平。隐丹参酮或 IC87114 的预处理逆转了 CSE 刺激的 U937 细胞中 HDAC 活性的降低。
隐丹参酮通过抑制 PI3Kδ 恢复氧化应激诱导的皮质类固醇敏感性，是治疗皮质类固醇不敏感疾病（如 COPD）的潜在药物。
