Ho Anita K, Jeganathan Fiona, Bictash Magda, Chen Han-Jou
York Biomedical Research Institute, Department of Biology, University of York, Wentworth Way, York YO10 5DD, UK.
Alzheimer's Research UK UCL Drug Discovery Institute, University College London, The Cruciform Building, Gower Street, London WC1E 6BT, London WC1E 6BT, UK.
Biomed Pharmacother. 2025 Jun;187:118049. doi: 10.1016/j.biopha.2025.118049. Epub 2025 Apr 15.
A pathological hallmark of neurodegenerative disease is the accumulation of aberrant protein aggregates which contribute to the cytotoxicity and are therefore a target for therapy development. One key mechanism to manage cellular protein homeostasis is heat shock proteins (HSPs), protein chaperones which are known to target aberrant protein accumulation. Activation of HSPs target aberrant TDP-43, tau and amyloid to rescue neurodegenerative disease. As an attempt to target HSP activation for neurodegeneration therapy, we here develop a drug screening assay to identify compounds that will activate the master regulator of HSPs, the transcription factor heat shock factor 1 (HSF1). As HSF1 is bound by HSP90 which prevents its activation, we developed a NanoBRET assay, which allows us to monitor and quantify the HSF1-HSP90 interaction in living cells to screen for compounds disrupting this interaction and thereby releasing HSF1 for activation. After the optimisation and validation of the assay, a two thousand compound library was screened which produced 10 hits including two known HSP90 inhibitors. Follow-up functional study showed that one of the hits oxyphenbutazone (OPB) significantly reduces the accumulation of insoluble TDP-43 in a cell model, eliciting no signs of stress or toxicity. Overall, this study demonstrates a viable strategy for new drug discovery in targeting aberrant proteins and identifies potential candidates for translation into neurodegenerative disease treatment.
神经退行性疾病的一个病理标志是异常蛋白质聚集体的积累，这些聚集体会导致细胞毒性，因此是治疗开发的一个靶点。维持细胞蛋白质稳态的一个关键机制是热休克蛋白（HSPs），这是一种已知可针对异常蛋白质积累的蛋白质伴侣。HSPs的激活可靶向异常的TDP-43、tau蛋白和淀粉样蛋白，以挽救神经退行性疾病。作为针对神经退行性疾病治疗靶向HSP激活的一种尝试，我们在此开发了一种药物筛选试验，以鉴定能够激活HSPs的主调节因子——转录因子热休克因子1（HSF1）的化合物。由于HSF1被HSP90结合，从而阻止其激活，我们开发了一种纳米生物发光共振能量转移（NanoBRET）试验，该试验使我们能够监测和量化活细胞中HSF1与HSP90的相互作用，以筛选破坏这种相互作用从而释放HSF1进行激活的化合物。在对该试验进行优化和验证后，对一个包含两千种化合物的文库进行了筛选，结果产生了10个命中化合物，其中包括两种已知的HSP90抑制剂。后续的功能研究表明，其中一个命中化合物羟基保泰松（OPB）在细胞模型中显著减少了不溶性TDP-43的积累，且未引发应激或毒性迹象。总体而言，本研究展示了一种针对异常蛋白质进行新药发现的可行策略，并确定了有望转化为神经退行性疾病治疗药物的潜在候选物。
