Mateusz Marynowski, Seweryn Karbownik Michał, Janusz Szemraj, Piotr Kuna, Panek Michał Gabriel
Department of Internal Medicine, Asthma and Allergy, Medical University of Lodz, Lodz, Lodzkie, Poland.
Department of Pharmacology and Toxicology, Medical University of Lodz, Lodz, Lodzkie, Poland.
Clin Transl Allergy. 2024 Jan;14(1):e12320. doi: 10.1002/clt2.12320.
A key player in the fibrotic process is the transforming growth factor β (TGF-β) which enhances extracellular matrix production by increasing the transcription of matrix proteins. The cytokine TGF-β first binds to the TGFβRII receptor (dimer), resulting in the recruitment of the TGFβRI receptor (dimer). The complex thus formed leads to the phosphorylation of the kinase domain of TGFβRI, which in turn results in activation of the Smad pathway. This is therefore a targeted pathway for research into the application of peptide inhibitors in blocking the TGF-β-Smad signaling pathway. The aim of this study was to design a peptide inhibitor (homologous to the cytokine TGF-β) which, after binding to the TGFβRI/TGFβRII receptor, would block the cytokine binding and thus prevent the formation of an activating complex.
Preliminary work on the design and synthesis of inhibitors for TGFβRI/TGFβRII has allowed us to identify and describe five key regions of the TGF-β-TGFβRI/TGFβRII interface. The following five peptide inhibitors were synthesized for Region 1: 1.1 ALDAAYCFR, 1.2 LDAAYCFRN, 1.3 DAAYCFRNV, 1.4 AAYCFRNVQ, 1.5 AYCFRNVQD. The expression of the SEAP reporter gene, Smad2, Smad3, Smad4, and JNK1 gene was measured using quantitative real-time polymerase chain reaction.
For Region 1 peptide inhibitors tested for TGFβRI/TGFβRII, reduced SEAP (reporter gene) expression was observed in cells of the MFB-F11 line, which suggests inhibited the formation of cytokine-receptor complexes.
For IP1_2, 1_3 and 1_5 Region 1 peptides tested for TGFβRI/TGFβRII, reduced cytokine-receptor signal by adding newly designed inhibitors. The study revealed an impact of these peptide inhibitors on the reduction of mRNA expression of Smad2, Smad3, Smad4 and JNK1 genes.
转化生长因子β（TGF-β）是纤维化过程中的关键因子，它通过增加基质蛋白的转录来增强细胞外基质的产生。细胞因子TGF-β首先与TGFβRII受体（二聚体）结合，导致TGFβRI受体（二聚体）的募集。由此形成的复合物导致TGFβRI激酶结构域的磷酸化，进而导致Smad信号通路的激活。因此，这是研究肽抑制剂在阻断TGF-β-Smad信号通路中应用的一个靶向途径。本研究的目的是设计一种肽抑制剂（与细胞因子TGF-β同源），该抑制剂在与TGFβRI/TGFβRII受体结合后，会阻断细胞因子结合，从而防止激活复合物的形成。
对TGFβRI/TGFβRII抑制剂的设计和合成进行的初步工作，使我们能够识别和描述TGF-β-TGFβRI/TGFβRII界面的五个关键区域。针对区域1合成了以下五种肽抑制剂：1.1 ALDAAYCFR、1.2 LDAAYCFRN、1.3 DAAYCFRNV、1.4 AAYCFRNVQ、1.5 AYCFRNVQD。使用定量实时聚合酶链反应测量SEAP报告基因、Smad2、Smad3、Smad4和JNK1基因的表达。
对于测试TGFβRI/TGFβRII的区域1肽抑制剂，在MFB-F11系细胞中观察到SEAP（报告基因）表达降低，这表明细胞因子-受体复合物的形成受到抑制。
对于测试TGFβRI/TGFβRII的IP1_2、1_3和1_5区域1肽，通过添加新设计的抑制剂降低了细胞因子-受体信号。该研究揭示了这些肽抑制剂对降低Smad2、Smad3、Smad4和JNK1基因mRNA表达的影响。
