Regulation of myeloid cell phagocytosis by LRRK2 via WAVE2 complex stabilization is altered in Parkinson’s disease

Leucine-rich repeat kinase 2 (LRRK2) has been implicated in both familial and sporadic Parkinson’s disease (PD), yet its pathogenic role remains unclear. A previous screen in Drosophila identified Scar/WAVE (Wiskott-Aldrich syndrome protein-family verproline) proteins as potential genetic interactors of LRRK2. Here, we provide evidence that LRRK2 modulates the phagocytic response of myeloid cells via specific modulation of the actin-cytoskeletal regulator, WAVE2. We demonstrate that macrophages and microglia from LRRK2–G2019S PD patients and mice display a WAVE2-mediated increase in phagocytic response, respectively. Lrrk2 loss results in the opposite effect. LRRK2 binds and phosphorylates Wave2 at Thr470, stabilizing and preventing its proteasomal degradation. Finally, we show that Wave2 also mediates Lrrk2–G2019S-induced dopaminergic neuronal death in both macrophage-midbrain cocultures and in vivo. Taken together, a LRRK2–WAVE2 pathway, which modulates the phagocytic response in mice and human leukocytes, may define an important role for altered immune function in PD.

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Pharmacological rescue of impaired mitophagy in Parkinson’s disease-related LRRK2 G2019S knock-in mice

10.1101/2020.12.07.414359 ◽

2020 ◽

Author(s):

Francois Singh ◽

Alan R. Prescott ◽

Graeme Ball ◽

Alastair D. Reith ◽

Ian G. Ganley

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Kinase Inhibitors ◽

Kinase Inhibitor ◽

Neurodegenerative Disorder ◽

Reporter Mice ◽

Lrrk2 G2019s ◽

Lrrk2 Kinase

AbstractParkinson’s disease (PD) is a major and progressive neurodegenerative disorder, yet the biological mechanisms involved in its aetiology are poorly understood. Evidence links this disorder with mitochondrial dysfunction and/or impaired lysosomal degradation – key features of the autophagy of mitochondria, known as mitophagy. Here we investigated the role of LRRK2, a protein kinase frequently mutated in PD, on this process in vivo. Using mitophagy and autophagy reporter mice, bearing either knockout of LRRK2 or expressing the pathogenic kinase-activating G2019S LRRK2 mutation, we found that basal mitophagy was specifically altered in clinically relevant cells and tissues. Our data show that basal mitophagy inversely correlates with LRRK2 kinase activity in vivo. In support of this, use of distinct LRRK2 kinase inhibitors in cells increased basal mitophagy, and a CNS penetrant LRRK2 kinase inhibitor, GSK3357679A, rescued the mitophagy defects observed in LRRK2 G2019S mice. This study provides the first in vivo evidence that pathogenic LRRK2 directly impairs basal mitophagy, a process with strong links to idiopathic Parkinson’s disease, and demonstrates that pharmacological inhibition of LRRK2 is a rational mitophagy-rescue approach and potential PD therapy.

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Protein synthesis is suppressed in sporadic and familial Parkinson’s Disease by LRRK2

10.1101/2020.04.27.053694 ◽

2020 ◽

Author(s):

Prasannakumar Deshpande ◽

Dani Flinkman ◽

Ye Hong ◽

Elena Goltseva ◽

Valentina Siino ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Protein Synthesis ◽

Gene Knockout ◽

Common Mutation ◽

Pathological Mechanism ◽

Lrrk2 Gene ◽

Lrrk2 G2019s ◽

Sporadic Parkinson’S Disease ◽

Or Gene

ABSTRACTGain of function LRRK2-G2019S is the most common mutation associated with both familial and sporadic Parkinson’s disease. It is expected therefore that understanding the cellular function of LRRK2 will provide much needed insight on the pathological mechanism of sporadic Parkinson’s, which is the most common form. Here we show that constitutive LRRK2 activity represses nascent protein synthesis in rodent neurons. Specifically, enzymatic inhibition of LRRK2, gene silencing or gene knockout of Lrrk2 increase translation. In the rotenone model of Parkinson’s, LRRK2 activity increases, leading to repression of translation and dopaminergic neuron atrophy both of which are prevented by LRRK2 inhibition. This is accompanied by altered phosphorylation of eIF2α-S52(↑), eIF2s2-S2(↓) and eEF2-T57(↑) in striatum/substantia nigra in a direction that signifies inhibition of protein synthesis. Significantly, LRRK2 is activated and translation is 40% reduced in Parkinson’s patient fibroblasts (G2019S and sporadic) and LRRK2 inhibition restores normal translation. In contrast, translation is unchanged in cells from multiple system atrophy patients, implying disease specificity. These findings suggest that LRRK2-dependent repression of translation may be a proximal function of LRRK2 in Parkinson’s pathology.

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Pharmacological rescue of impaired mitophagy in Parkinson’s disease-related LRRK2 G2019S knock-in mice

eLife ◽

10.7554/elife.67604 ◽

2021 ◽

Vol 10 ◽

Author(s):

Francois Singh ◽

Alan R Prescott ◽

Philippa Rosewell ◽

Graeme Ball ◽

Alastair D Reith ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Kinase Inhibitors ◽

Kinase Inhibitor ◽

Neurodegenerative Disorder ◽

Reporter Mice ◽

Lrrk2 G2019s ◽

Lrrk2 Kinase

Parkinson’s disease (PD) is a major and progressive neurodegenerative disorder, yet the biological mechanisms involved in its aetiology are poorly understood. Evidence links this disorder with mitochondrial dysfunction and/or impaired lysosomal degradation – key features of the autophagy of mitochondria, known as mitophagy. Here, we investigated the role of LRRK2, a protein kinase frequently mutated in PD, in this process in vivo. Using mitophagy and autophagy reporter mice, bearing either knockout of LRRK2 or expressing the pathogenic kinase-activating G2019S LRRK2 mutation, we found that basal mitophagy was specifically altered in clinically relevant cells and tissues. Our data show that basal mitophagy inversely correlates with LRRK2 kinase activity in vivo. In support of this, use of distinct LRRK2 kinase inhibitors in cells increased basal mitophagy, and a CNS penetrant LRRK2 kinase inhibitor, GSK3357679A, rescued the mitophagy defects observed in LRRK2 G2019S mice. This study provides the first in vivo evidence that pathogenic LRRK2 directly impairs basal mitophagy, a process with strong links to idiopathic Parkinson’s disease, and demonstrates that pharmacological inhibition of LRRK2 is a rational mitophagy-rescue approach and potential PD therapy.

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In vivo multimodal (MRI, SPECT) imaging of the 6-OHDA rat model for Parkinson's disease correlated with behavior and histology

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/sj.jcbfm.9591524.0392 ◽

2005 ◽

Vol 25 (1_suppl) ◽

pp. S392-S392

Author(s):

Nadja Van Camp ◽

Koen Van Laere ◽

Ruth Vreys ◽

Marleen Verhoye ◽

Erwin Lauwers ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Rat Model ◽

Spect Imaging ◽

Multimodal Mri

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Pharmacological treatment with L-DOPA may reduce striatal dopamine transporter binding in in vivo imaging studies

Nuklearmedizin ◽

10.3413/nukmed-0764-15-08 ◽

2016 ◽

Vol 55 (01) ◽

pp. 21-28 ◽

Cited By ~ 4

Author(s):

C. Antke ◽

H. Hautzel ◽

H.-W. Mueller ◽

S. Nikolaus

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Binding Sites ◽

Human Subjects ◽

Synaptic Cleft ◽

Presynaptic Terminal ◽

Imaging Studies ◽

Psychiatric Conditions ◽

Da Release

SummaryNumerous neurologic and psychiatric conditions are treated with pharmacological compounds, which lead to an increase of synaptic dopamine (DA) levels. One example is the DA precursor L-3,4-dihydroxyphenylalanine (L-DOPA), which is converted to DA in the presynaptic terminal. If the increase of DA concentrations in the synaptic cleft leads to competition with exogenous radioligands for presynaptic binding sites, this may have implications for DA transporter (DAT) imaging studies in patients under DAergic medication.This paper gives an overview on those findings, which, so far, have been obtained on DAT binding in human Parkinson’s disease after treatment with L-DOPA. Findings, moreover, are related to results obtained on rats, mice or non-human primates. Results indicate that DAT imaging may be reduced in the striata of healthy animals, in the unlesioned striata of animal models of unilateral Parkinson’s disease and in less severly impaired striata of Parkinsonian patients, if animal or human subjects are under acute or subchronic treatment with L-DOPA. If also striatal DAT binding is susceptible to alterations of synaptic DA levels, this may allow to quantify DA reuptake in analogy to DA release by assessing the competition between endogenous DA and the administered exogenous DAT radioligand.

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Multiple Pathways of LRRK2-G2019S/Rab10 Interaction in Dopaminergic Neurons

Journal of Parkinson s Disease ◽

10.3233/jpd-202421 ◽

2021 ◽

pp. 1-16

Author(s):

Alison Fellgett ◽

C. Adam Middleton ◽

Jack Munns ◽

Chris Ugbode ◽

David Jaciuch ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Dopaminergic Neurons ◽

Genetic Interaction ◽

In Vitro Assays ◽

Rab Proteins ◽

Circadian Activity ◽

Loss Of Function ◽

Lrrk2 G2019s

Background: Inherited mutations in the LRRK2 protein are the common causes of Parkinson’s disease, but the mechanisms by which increased kinase activity of mutant LRRK2 leads to pathological events remain to be determined. In vitro assays (heterologous cell culture, phospho-protein mass spectrometry) suggest that several Rab proteins might be directly phosphorylated by LRRK2-G2019S. An in vivo screen of Rab expression in dopaminergic neurons in young adult Drosophila demonstrated a strong genetic interaction between LRRK2-G2019S and Rab10. Objective: To determine if Rab10 is necessary for LRRK2-induced pathophysiological responses in the neurons that control movement, vision, circadian activity, and memory. These four systems were chosen because they are modulated by dopaminergic neurons in both humans and flies. Methods: LRRK2-G2019S was expressed in Drosophila dopaminergic neurons and the effects of Rab10 depletion on Proboscis Extension, retinal neurophysiology, circadian activity pattern (‘sleep’), and courtship memory determined in aged flies. Results: Rab10 loss-of-function rescued LRRK2-G2019S induced bradykinesia and retinal signaling deficits. Rab10 knock-down, however, did not rescue the marked sleep phenotype which results from dopaminergic LRRK2-G2019S. Courtship memory is not affected by LRRK2, but is markedly improved by Rab10 depletion. Anatomically, both LRRK2-G2019S and Rab10 are seen in the cytoplasm and at the synaptic endings of dopaminergic neurons. Conclusion: We conclude that, in Drosophila dopaminergic neurons, Rab10 is involved in some, but not all, LRRK2-induced behavioral deficits. Therefore, variations in Rab expression may contribute to susceptibility of different dopaminergic nuclei to neurodegeneration seen in people with Parkinson’s disease.

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Growth Factor Therapy for Parkinson’s Disease: Alternative Delivery Systems

Journal of Parkinson s Disease ◽

10.3233/jpd-212662 ◽

2021 ◽

pp. 1-7

Author(s):

Sarah Jarrin ◽

Abrar Hakami ◽

Ben Newland ◽

Eilís Dowd

Keyword(s):

Parkinson’S Disease ◽

Gene Therapy ◽

Parkinson's Disease ◽

Growth Factors ◽

Growth Factor ◽

Ex Vivo ◽

Brain Regions ◽

Delivery Systems ◽

Alternative Delivery

Despite decades of research and billions in global investment, there remains no preventative or curative treatment for any neurodegenerative condition, including Parkinson’s disease (PD). Arguably, the most promising approach for neuroprotection and neurorestoration in PD is using growth factors which can promote the growth and survival of degenerating neurons. However, although neurotrophin therapy may seem like the ideal approach for neurodegenerative disease, the use of growth factors as drugs presents major challenges because of their protein structure which creates serious hurdles related to accessing the brain and specific targeting of affected brain regions. To address these challenges, several different delivery systems have been developed, and two major approaches—direct infusion of the growth factor protein into the target brain region and in vivo gene therapy—have progressed to clinical trials in patients with PD. In addition to these clinically evaluated approaches, a range of other delivery methods are in various degrees of development, each with their own unique potential. This review will give a short overview of some of these alternative delivery systems, with a focus on ex vivo gene therapy and biomaterial-aided protein and gene delivery, and will provide some perspectives on their potential for clinical development and translation.

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Effectiveness and mechanisms of adipose-derived stem cell therapy in animal models of Parkinson’s disease: a systematic review and meta-analysis

Translational Neurodegeneration ◽

10.1186/s40035-021-00238-1 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Keya Li ◽

Xinyue Li ◽

Guiying Shi ◽

Xuepei Lei ◽

Yiying Huang ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Animal Models ◽

Therapeutic Option ◽

Meta Analysis ◽

Future Application ◽

Neuroprotective Effects ◽

Standard Mean Difference ◽

Study Characteristics

AbstractAnimal models provide an opportunity to assess the optimal treatment way and the underlying mechanisms of direct clinical application of adipose-derived stem cells (ADSCs). Previous studies have evaluated the effects of primitive and induced ADSCs in animal models of Parkinson’s disease (PD). Here, eight databases were systematically searched for studies on the effects and in vivo changes caused by ADSC intervention. Quality assessment was conducted using a 10-item risk of bias tool. For the subsequent meta-analysis, study characteristics were extracted and effect sizes were computed. Ten out of 2324 published articles (n = 169 animals) were selected for further meta-analysis. After ADSC therapy, the rotation behavior (10 experiments, n = 156 animals) and rotarod performance (3 experiments, n = 54 animals) were improved (P < 0.000 01 and P = 0.000 3, respectively). The rotation behavior test reflected functional recovery, which may be due to the neurogenesis from neuronally differentiated ADSCs, resulting in a higher pooled effect size of standard mean difference (SMD) (− 2.59; 95% CI, − 3.57 to − 1.61) when compared to that of primitive cells (− 2.18; 95% CI, − 3.29 to − 1.07). Stratified analyses by different time intervals indicated that ADSC intervention exhibited a long-term effect. Following the transplantation of ADSCs, tyrosine hydroxylase-positive neurons recovered in the lesion area with pooled SMD of 13.36 [6.85, 19.86]. Transplantation of ADSCs is a therapeutic option that shows long-lasting effects in animal models of PD. The potential mechanisms of ADSCs involve neurogenesis and neuroprotective effects. The standardized induction of neural form of transplanted ADSCs can lead to a future application in clinical practice.

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Grafts Derived from an α-Synuclein Triplication Patient Mediate Functional Recovery but Develop Disease-Associated Pathology in the 6-OHDA Model of Parkinson’s Disease

Journal of Parkinson s Disease ◽

10.3233/jpd-202366 ◽

2020 ◽

pp. 1-14

Author(s):

Shelby Shrigley ◽

Fredrik Nilsson ◽

Bengt Mattsson ◽

Alessandro Fiorenzano ◽

Janitha Mudannayake ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Cell Lines ◽

Functional Recovery ◽

Embryonic Stem ◽

Hesc Line ◽

Alternative Source ◽

And Function

Background: Human induced pluripotent stem cells (hiPSCs) have been proposed as an alternative source for cell replacement therapy for Parkinson’s disease (PD) and they provide the option of using the patient’s own cells. A few studies have investigated transplantation of patient-derived dopaminergic (DA) neurons in preclinical models; however, little is known about the long-term integrity and function of grafts derived from patients with PD. Objective: To assess the viability and function of DA neuron grafts derived from a patient hiPSC line with an α-synuclein gene triplication (AST18), using a clinical grade human embryonic stem cell (hESC) line (RC17) as a reference control. Methods: Cells were differentiated into ventral mesencephalic (VM)-patterned DA progenitors using an established GMP protocol. The progenitors were then either terminally differentiated to mature DA neurons in vitro or transplanted into 6-hydroxydopamine (6-OHDA) lesioned rats and their survival, maturation, function, and propensity to develop α-synuclein related pathology, were assessed in vivo. Results: Both cell lines generated functional neurons with DA properties in vitro. AST18-derived VM progenitor cells survived transplantation and matured into neuron-rich grafts similar to the RC17 cells. After 24 weeks, both cell lines produced DA-rich grafts that mediated full functional recovery; however, pathological changes were only observed in grafts derived from the α-synuclein triplication patient line. Conclusion: This data shows proof-of-principle for survival and functional recovery with familial PD patient-derived cells in the 6-OHDA model of PD. However, signs of slowly developing pathology warrants further investigation before use of autologous grafts in patients.

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The Nigral Coup in Parkinson’s Disease by α-Synuclein and Its Associated Rebels

Cells ◽

10.3390/cells10030598 ◽

2021 ◽

Vol 10 (3) ◽

pp. 598

Author(s):

Jeswinder Sian-Hulsmann ◽

Peter Riederer

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Viral Infections ◽

Genetic Defect ◽

Lewy Bodies ◽

Common Denominator ◽

Metabolic Disturbances ◽

Trigger Factors ◽

Protein Clearance ◽

Sporadic Parkinson’S Disease

The risk of Parkinson’s disease increases with age. However, the etiology of the illness remains obscure. It appears highly likely that the neurodegenerative processes involve an array of elements that influence each other. In addition, genetic, endogenous, or exogenous toxins need to be considered as viable partners to the cellular degeneration. There is compelling evidence that indicate the key involvement of modified α-synuclein (Lewy bodies) at the very core of the pathogenesis of the disease. The accumulation of misfolded α-synuclein may be a consequence of some genetic defect or/and a failure of the protein clearance system. Importantly, α-synuclein pathology appears to be a common denominator for many cellular deleterious events such as oxidative stress, mitochondrial dysfunction, dopamine synaptic dysregulation, iron dyshomeostasis, and neuroinflammation. These factors probably employ a common apoptotic/or autophagic route in the final stages to execute cell death. The misfolded α-synuclein inclusions skillfully trigger or navigate these processes and thus amplify the dopamine neuron fatalities. Although the process of neuroinflammation may represent a secondary event, nevertheless, it executes a fundamental role in neurodegeneration. Some viral infections produce parkinsonism and exhibit similar characteristic neuropathological changes such as a modest brain dopamine deficit and α-synuclein pathology. Thus, viral infections may heighten the risk of developing PD. Alternatively, α-synuclein pathology may induce a dysfunctional immune system. Thus, sporadic Parkinson’s disease is caused by multifactorial trigger factors and metabolic disturbances, which need to be considered for the development of potential drugs in the disorder.

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