Instituto de Investigación, Desarrollo e Innovación en Biotecnología Sanitaria de Elche (IDiBE), Universidad Miguel Hernández de Elche, Alicante, Spain.
CIBER de Diabetes y Enfermedades Metabólicas Asociadas, Instituto de Salud Carlos III, Madrid, Spain.
Front Immunol. 2023 Oct 3;14:1263926. doi: 10.3389/fimmu.2023.1263926. eCollection 2023.
Type 1 diabetes is characterized by pancreatic islet inflammation and autoimmune-driven pancreatic β-cell destruction. Interferon-α (IFNα) is a key player in early human type 1 diabetes pathogenesis. IFNα activates the tyrosine kinase 2 (TYK2)-signal transducer and activator of transcription (STAT) pathway, leading to inflammation, HLA class I overexpression, endoplasmic reticulum (ER) stress, and β-cell apoptosis (in synergy with IL-1β). As TYK2 inhibition has raised as a potential therapeutic target for the prevention or treatment of type 1 diabetes, we investigated whether the selective TYK2 inhibitor deucravacitinib could protect β-cells from the effects of IFNα and other proinflammatory cytokines (i.e., IFNγ and IL-1β).
All experiments were performed in the human EndoC-βH1 β-cell line. HLA class I expression, inflammation, and ER stress were evaluated by real-time PCR, immunoblotting, and/or immunofluorescence. Apoptosis was assessed by the DNA-binding dyes Hoechst 33342 and propidium iodide or caspase 3/7 activity. The promoter activity was assessed by luciferase assay.
Deucravacitinib prevented IFNα effects, such as STAT1 and STAT2 activation and MHC class I hyperexpression, in a dose-dependent manner without affecting β-cell survival and function. A comparison between deucravacitinib and two Janus kinase inhibitors, ruxolitinib and baricitinib, showed that deucravacitinib blocked IFNα- but not IFNγ-induced signaling pathway. Deucravacitinib protected β-cells from the effects of two different combinations of cytokines: IFNα + IL-1β and IFNγ + IL-1β. Moreover, this TYK2 inhibitor could partially reduce apoptosis and inflammation in cells pre-treated with IFNα + IL-1β or IFNγ + IL-1β.
Our findings suggest that, by protecting β-cells against the deleterious effects of proinflammatory cytokines without affecting β-cell function and survival, deucravacitinib could be repurposed for the prevention or treatment of early type 1 diabetes.
1 型糖尿病的特征是胰岛炎症和自身免疫驱动的胰岛β细胞破坏。干扰素-α（IFNα）是人类 1 型糖尿病发病机制中的关键因素。IFNα 激活酪氨酸激酶 2（TYK2）-信号转导和转录激活因子（STAT）途径，导致炎症、HLA Ⅰ类分子过度表达、内质网（ER）应激和β细胞凋亡（与 IL-1β协同作用）。由于 TYK2 抑制已被提出作为预防或治疗 1 型糖尿病的潜在治疗靶点，我们研究了选择性 TYK2 抑制剂地达西替尼是否可以保护β细胞免受 IFNα 和其他促炎细胞因子（即 IFNγ 和 IL-1β）的影响。
所有实验均在人 EndoC-βH1 β细胞系中进行。通过实时 PCR、免疫印迹和/或免疫荧光评估 HLA Ⅰ类分子表达、炎症和 ER 应激。通过 Hoechst 33342 和碘化丙啶或 caspase 3/7 活性评估细胞凋亡。通过荧光素酶测定评估启动子活性。
地达西替尼以剂量依赖的方式阻止 IFNα 的作用，如 STAT1 和 STAT2 激活和 MHC Ⅰ类分子过度表达，而不影响β细胞的存活和功能。地达西替尼与两种 Janus 激酶抑制剂鲁索利替尼和巴瑞替尼的比较表明，地达西替尼阻断了 IFNα-但不阻断 IFNγ-诱导的信号通路。地达西替尼保护β细胞免受两种不同细胞因子组合的影响：IFNα+IL-1β和 IFNγ+IL-1β。此外，这种 TYK2 抑制剂可以部分减少经 IFNα+IL-1β或 IFNγ+IL-1β预处理的细胞中的凋亡和炎症。
我们的研究结果表明，地达西替尼通过保护β细胞免受促炎细胞因子的有害影响，而不影响β细胞的功能和存活，可以被重新用于预防或治疗早期 1 型糖尿病。
