Mutations in leucine-rich repeat kinase 2 (LRRK2) are the most common cause of late-onset, autosomal-dominant familial Parkinson’s disease (PD). LRRK2 functions as both a kinase and GTPase, and PD-linked mutations are known to influence both enzymatic activities. While PD-linked LRRK2 mutations can commonly induce neuronal damage in culture models, the mechanisms underlying these pathogenic effects remain uncertain. Rodent models containing familial LRRK2 mutations often lack robust PD-like neurodegenerative phenotypes. Here, we develop a robust preclinical model of PD in adult rats induced by the brain delivery of recombinant adenoviral vectors with neuronal-specific expression of human LRRK2 harboring the most common G2019S mutation. In this model, G2019S LRRK2 induces the robust degeneration of substantia nigra dopaminergic neurons, a pathological hallmark of PD. Introduction of a stable kinase-inactive mutation or administration of the selective kinase inhibitor, PF-360, attenuates neurodegeneration induced by G2019S LRRK2. Neuroprotection provided by pharmacological kinase inhibition is mediated by an unusual mechanism involving the robust destabilization of human LRRK2 protein in the brain relative to endogenous LRRK2. Our study further demonstrates that G2019S LRRK2-induced dopaminergic neurodegeneration critically requires normal GTPase activity, as hypothesis-testing mutations that increase GTP hydrolysis or impair GTP-binding activity provide neuroprotection although via distinct mechanisms. Taken together, our data demonstrate that G2019S LRRK2 induces neurodegeneration in vivo via a mechanism that is dependent on kinase and GTPase activity. Our study provides a robust rodent preclinical model of LRRK2-linked PD and nominates kinase inhibition and modulation of GTPase activity as promising disease-modifying therapeutic targets.

富含亮氨酸的重复激酶2（LRRK2）中的突变）是晚发型常染色体显性家族性帕金森病（PD）的最常见原因。LRRK2既可作为激酶又可作为GTP酶，并且已知PD连接的突变会影响这两种酶的活性。虽然PD关联的LRRK2突变通常可以在培养模型中诱导神经元损伤，但这些致病作用的潜在机制仍不确定。含有家族性LRRK2突变的啮齿动物模型通常缺乏健壮的PD样神经退行性表型。在这里，我们建立了成年大鼠PD的稳健的临床前模型，该模型是通过脑部递送重组腺病毒载体（具有人类LRRK2的神经元特异性表达）携带最常见的G2019S突变而诱导的。在该模型中，G2019S LRRK2诱导黑质多巴胺能神经元的强烈变性，这是PD的病理学特征。引入稳定的激酶失活突变或施用选择性激酶抑制剂PF-360可减轻G2019S LRRK2诱导的神经变性。药理激酶抑制作用提供的神经保护作用是通过一种异常机制介导的，该机制涉及大脑中人LRRK2蛋白相对于内源性LRRK2的强烈失稳。我们的研究进一步证明，G2019S LRRK2诱导的多巴胺能神经变性至关重要地需要正常的GTPase活性，因为通过GTP水解或损害GTP结合活性的假设检验突变可通过不同的机制提供神经保护作用。两者合计，我们的数据表明G2019S LRRK2通过依赖于激酶和GTPase活性的机制在体内诱导神经变性。我们的研究提供了一个强大的啮齿动物的临床前模型LRRK2连锁的PD，并提名激酶抑制和GTPase活性调节作为有希望的疾病修饰治疗靶点。