Department of Molecules - Signaling - Development, Max Planck Institute for Biological Intelligence, Martinsried, Germany.
Molecular Neurodegeneration Group, Max Planck Institute for Biological Intelligence, Martinsried, Germany.
Life Sci Alliance. 2023 Aug 14;6(11). doi: 10.26508/lsa.202302018. Print 2023 Nov.
Huntington's disease (HD) is a movement disorder caused by a mutation in the Huntingtin gene that leads to severe neurodegeneration. Molecular mechanisms of HD are not sufficiently understood, and no cure is currently available. Here, we demonstrate neuroprotective effects of hepatoma-derived growth factor (HDGF) in cellular and mouse HD models. We show that HD-vulnerable neurons in the striatum and cortex express lower levels of HDGF than resistant ones. Moreover, lack of endogenous HDGF exacerbated motor impairments and reduced the life span of R6/2 Huntington's disease mice. AAV-mediated delivery of HDGF into the brain reduced mutant Huntingtin inclusion load, but had no significant effect on motor behavior or life span. Interestingly, both nuclear and cytoplasmic versions of HDGF were efficient in rescuing mutant Huntingtin toxicity in cellular HD models. Moreover, extracellular application of recombinant HDGF improved viability of mutant Huntingtin-expressing primary neurons and reduced mutant Huntingtin aggregation in neural progenitor cells differentiated from human patient-derived induced pluripotent stem cells. Our findings provide new insights into the pathomechanisms of HD and demonstrate neuroprotective potential of HDGF in neurodegeneration.
亨廷顿病（HD）是一种运动障碍，由亨廷顿基因的突变引起，导致严重的神经退行性变。HD 的分子机制尚未得到充分理解，目前尚无治愈方法。在这里，我们在细胞和小鼠 HD 模型中证明了肝癌衍生生长因子（HDGF）的神经保护作用。我们发现纹状体和皮层中易受 HD 影响的神经元表达的 HDGF 水平低于抗性神经元。此外，内源性 HDGF 的缺乏加剧了运动障碍并缩短了 R6/2 亨廷顿病小鼠的寿命。AAV 介导的 HDGF 脑内传递减少了突变型亨廷顿蛋白包涵体的负荷，但对运动行为或寿命没有显著影响。有趣的是，HDGF 的核和细胞质两种形式在细胞 HD 模型中均能有效挽救突变型亨廷顿蛋白的毒性。此外，重组 HDGF 的细胞外应用提高了表达突变型亨廷顿蛋白的原代神经元的活力，并减少了从人类患者来源的诱导多能干细胞分化而来的神经祖细胞中突变型亨廷顿蛋白的聚集。我们的研究结果为 HD 的发病机制提供了新的见解，并证明了 HDGF 在神经退行性变中的神经保护潜力。
