Publications by authors named "Shu Leong Ho"

Article Synopsis
  • The study investigates how mutations in the LRRK2 gene, linked to Parkinson's disease, affect mitochondrial function and calcium signaling during stress-induced cell damage.
  • In experiments, the researchers found that while wild-type cells exhibited a normal calcium surge in response to mitochondrial depolarization, LRRK2 mutant cells did not, indicating a disruption in the cellular response to damage.
  • Further analysis showed that this lack of response in mutant cells was associated with impaired activation of key kinases involved in the stress response, leading to swollen mitochondria and overall mitochondrial dysfunction.
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Objective: To investigate the effects of balance exercise and brisk walking on nonmotor and motor symptoms, balance and gait functions, walking capacity, and balance confidence in Parkinson disease (PD) at posttraining and 6-month follow-up.

Design: Two-arm, assessor-blinded randomized controlled trial SETTING: University research laboratory and the community PARTICIPANTS: Ninety-nine eligible individuals with mild-to-moderate PD INTERVENTIONS: Participants were randomized to balance and brisk walking group (B&B, n=49) or active control group (n=50). B&B received ten 90-minute sessions of balance exercises and brisk walking supervised by physical therapists for 6 months (week 1-6: weekly, week 7-26: monthly), whereas control practiced whole-body flexibility and upper limb strength exercise at same dosage (180 min/wk).

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Background: Major intracerebral hemorrhage (ICH) trials have largely been unable to demonstrate therapeutic benefit in improving functional outcomes. This may be partly due to the heterogeneity of ICH outcomes based on their location, where a small strategic ICH could be debilitating, thus confounding therapeutic effects. We aimed to determine the ideal hematoma volume cutoff for different ICH locations in predicting ICH outcomes.

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Background: Leucine-rich repeat kinase 2 (LRRK2) mutation is a common genetic risk factor of Parkinson's disease (PD). Presynaptic dysfunction is an early pathogenic event associated with dopamine (DA) dysregulation in striatum of the brain. DA uptake activity of DA uptake transporter (DAT) affects synaptic plasticity and motor and non-motor behavior.

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Background: Intracerebral hemorrhage (ICH) survivors are at high risk for recurrent stroke and cardiovascular events. Blood pressure (BP) control represents the most potent intervention to lower these risks, but optimal treatment targets in this patient population remain unknown. We sought to determine whether survivors of ICH achieving more intensive BP control than current guideline recommendations (systolic BP <130 mmHg and diastolic BP <80 mmHg) were at lower risk of major adverse cardiovascular and cerebrovascular events and mortality.

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Parkinson's disease (PD) is characterized by dopaminergic neurodegeneration in nigrostriatal and cortical brain regions associated with pathogenic α-synuclein (αSyn) aggregate/oligomer accumulation. LRRK2 hyperactivity is a disease-modifying therapeutic target in PD. However, LRRK2 inhibition may be associated with peripheral effects, albeit with unclear clinical consequences.

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Synaptogyrin-3 (SYNGR3) is a synaptic vesicular membrane protein. Amongst four homologues (SYNGR1 to 4), SYNGR1 and 3 are especially abundant in the brain. SYNGR3 interacts with the dopamine transporter (DAT) to facilitate dopamine (DA) uptake and synaptic DA turnover in dopaminergic transmission.

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Background Survivors of intracranial hemorrhage (ICH) are at increased risk for major adverse cardiovascular and cerebrovascular events (MACCE), in the form of recurrent stroke and myocardial Infarction. We investigated whether long-term blood pressure (BP) variability represents a risk factor for MACCE after ICH, independent of average BP. Methods and Results We analyzed data from prospective ICH cohort studies at Massachusetts General Hospital and the University of Hong Kong.

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Mutations in the leucine-rich repeat kinase 2 gene (LRRK2) are one of the most frequent genetic causes of both familial and sporadic Parkinson's disease (PD). Mounting evidence has demonstrated pathological similarities between LRRK2-associated PD (LRRK2-PD) and sporadic PD, suggesting that LRRK2 is a potential disease modulator and a therapeutic target in PD. LRRK2 mutant knock-in (KI) mouse models display subtle alterations in pathological aspects that mirror early-stage PD, including increased susceptibility of nigrostriatal neurotransmission, development of motor and non-motor symptoms, mitochondrial and autophagy-lysosomal defects and synucleinopathies.

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Mutations in leucine-rich repeat kinase 2 (LRRK2) and glucocerebrosidase (GBA) represent two most common genetic causes of Parkinson's disease (PD). Both genes are important in the autophagic-lysosomal pathway (ALP), defects of which are associated with α-synuclein (α-syn) accumulation. LRRK2 regulates macroautophagy via activation of the mitogen activated protein kinase/extracellular signal regulated protein kinase (MAPK/ERK) kinase (MEK) and the calcium-dependent adenosine monophosphate (AMP)-activated protein kinase (AMPK) pathways.

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Parkinson's psychosis (PDP) describes a spectrum of symptoms that may arise in Parkinson's disease (PD) including visual hallucinations (VH). Imaging studies investigating the neural correlates of PDP have been inconsistent in their findings, due to differences in study design and limitations of scale. Here we use empirical Bayes harmonisation to pool together structural imaging data from multiple research groups into a large-scale mega-analysis, allowing us to identify cortical regions and networks involved in VH and their relation to receptor binding.

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Identifying rare variants that contribute to complex diseases is challenging because of the low statistical power in current tests comparing cases with controls. Here, we propose a novel and powerful rare variants association test based on the deviation of the observed mutation burden of a gene in cases from a baseline predicted by a weighted recursive truncated negative-binomial regression (RUNNER) on genomic features available from public data. Simulation studies show that RUNNER is substantially more powerful than state-of-the-art rare variant association tests and has reasonable type 1 error rates even for stratified populations or in small samples.

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Background Survivors of intracerebral hemorrhage (ICH) are at high risk for recurrent stroke, which is associated with blood pressure control. Because most recurrent stroke events occur within 12 to 18 months of the index ICH, rapid blood pressure control is likely to be crucial. We investigated the frequency and prognostic impact of uncontrolled short-term hypertension after ICH.

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Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition).
Daniel J Klionsky Amal Kamal Abdel-Aziz Sara Abdelfatah Mahmoud Abdellatif Asghar Abdoli Khosrow Adeli Holger W Auner Seung-Hoon Baek Shounak Baksi Lionel Berthoux Rhoderick E Brown Andreia Neves Carvalho Marzanna Cechowska-Pasko Zhong Chen King-Ho Cheung Dong-Hyung Cho Seong-Kyu Choe Augustine M K Choi Mary E Choi Kamalika Roy Choudhury Norman S Chow Seockhoon Chung Iwona A Ciechomska Hormos Salimi Dafsari Nicholas D Demers Hongbin Deng Thomas Efferth Gholamreza Fazeli Anthony O Fedele Thomas A Ferguson Anthony W Ferrante Shou-Jiang Gao Wanzhong Ge Manosij Ghosh Alexander Greenhough Kishore Guda Hongqing Guo Maho Hamasaki Thomas S Hays Emmanuel A Ho Idy H T Ho Philip Wing-Lok Ho Shu-Leong Ho Wan Yun Ho G Aaron Hobbs Mark Hochstrasser Peter H M Hoet Daniel Hofius Paul Hofman Carina I Holmberg Jose R Hombrebueno Chang-Won Hong Yi-Ren Hong Lora V Hooper Thorsten Hoppe Rastislav Horos Yujin Hoshida Chongmin Huan Shohreh Issazadeh-Navikas Thomas E Jensen Hongchuan Jin Widuri Kho Noopur V Khobrekar Jin-Hoi Kim Kerri J Kinghorn Thomas Klopstock Hotaka Kobayashi Young Ho Koh Nicholas T Ktistakis Thomas Kukar Ashok Kumar Ho Jeong Kwon Nicholas F LaRusso Yong-Ho Lee Guanghong Liao Dar-Shong Lin Xiao-Hong Liu Senka Ljubojevic-Holzer Jia-Hong Lu Honglin Luo Shouqing Luo Alex Lyakhovich Quan-Hong Ma Thomas G McWilliams Jose F Moruno-Manchon Subhadip Mukhopadhyay Ashok Munjal Jihoon Nah Thomas Neill Thomas P Neufeld Hong-Min Ni Zhenhong Ni Thorsten Pfirrmann Ainhoa Plaza-Zabala Thomas Pulinilkunnil Sumit Rathore Hongmei Ren Kasper M A Rouschop Avnika Ashok Ruparelia Amirhossein Sahebkar Ashok K Saluja Vanessa Sancho-Shimizu J Thomas Sanderson Anthony H V Schapira Romana Schober Alejandra C Schoijet Micah B Schott Hongtao Shen Ying-Hong Shi Kahori Shiba-Fukushima Christopher J Shoemaker Shahla Shojaei Ikuo Shoji Hong-Bing Shu Rohit Anthony Sinha Peter B Stathopulos Zhongjie Sun Stephen Cho Wing Sze Chong Teik Tan Lars Tatenhorst Sufi Mary Thomas Paul G Thomes Andrew Thorburn Thomas Thum Holm H Uhlig Thomas Vaccari Ilse Vanhorebeek Olga V Voitsekhovskaja Hong-Gang Wang Zhouguang Wang Maxinne Watchon Thomas Wollert Jack Ho Wong Shengzhou Wu Xiaohong Wu Hongguang Xia Hong-Tao Xiao Zhonglin Xie Honghong Yao Zhou Yu Jeanho Yun Hong Zhang Hong Zhang Honghe Zhang Shizhong Zheng Qing Zhong Ao Zhou Ben Zhou Cefan Zhou Gang Zhou Hao Zhou Hong Zhou Hongbo Zhou Jie Zhou Jing Zhou Jing Zhou Jiyong Zhou Kailiang Zhou Rongjia Zhou Xu-Jie Zhou Yanshuang Zhou Yinghong Zhou Yubin Zhou Zheng-Yu Zhou Zhou Zhou Hongxin Zhu Xiaohong Zhuang

Autophagy

January 2021

Article Synopsis
  • In 2008, guidelines were established for researching autophagy, which has since gained significant interest and new technologies, necessitating regular updates to monitoring methods across various organisms.
  • The new guidelines emphasize selecting appropriate techniques to evaluate autophagy while noting that no single method suits all situations; thus, a combination of methods is encouraged.
  • The document highlights that key proteins involved in autophagy also impact other cellular processes, suggesting genetic studies should focus on multiple autophagy-related genes to fully understand these pathways.
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Mitochondrial dysfunction causes energy deficiency and nigrostriatal neurodegeneration which is integral to the pathogenesis of Parkinson disease (PD). Clearance of defective mitochondria involves fission and ubiquitin-dependent degradation via mitophagy to maintain energy homeostasis. We hypothesize that LRRK2 (leucine-rich repeat kinase 2) mutation disrupts mitochondrial turnover causing accumulation of defective mitochondria in aging brain.

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Background: Parkinson's disease (PD) is characterized by dopaminergic neuronal loss in the substantia nigra pars compacta and intracellular inclusions called Lewy bodies (LB). During the course of disease, misfolded α-synuclein, the major constituent of LB, spreads to different regions of the brain in a prion-like fashion, giving rise to successive non-motor and motor symptoms. Etiology is likely multifactorial, and involves interplay among aging, genetic susceptibility and environmental factors.

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Parkinson disease (PD) is an age-related neurodegenerative disorder associated with misfolded SNCA/α-synuclein accumulation in brain. Impaired catabolism of SNCA potentiates formation of its toxic oligomers. (leucine-rich repeat kinase-2) mutations predispose to familial and sporadic PD.

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Mutations that activate the LRRK2 (leucine-rich repeat protein kinase 2) protein kinase predispose to Parkinson's disease, suggesting that LRRK2 inhibitors might have therapeutic benefit. Recent work has revealed that LRRK2 phosphorylates a subgroup of 14 Rab proteins, including Rab10, at a specific residue located at the centre of its effector-binding switch-II motif. In the present study, we analyse the selectivity and sensitivity of polyclonal and monoclonal phospho-specific antibodies raised against nine different LRRK2-phosphorylated Rab proteins (Rab3A/3B/3C/3D, Rab5A/5B/5C, Rab8A/8B, Rab10, Rab12, Rab29[T71], Rab29[S72], Rab35 and Rab43).

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The clinical diagnosis of neurodegenerative disorders based on phenotype is difficult in heterogeneous conditions with overlapping symptoms. It does not take into account the disease etiology or the highly variable clinical course even amongst patients diagnosed with the same disorder. The advent of next generation sequencing (NGS) has allowed for a system-wide, unbiased approach to identify all gene variants in the genome simultaneously.

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Genetic variants are implicated in the development of amyotrophic lateral sclerosis (ALS), but it is unclear whether the burden of rare variants in ALS genes has an effect on survival. We performed whole genome sequencing on 8 familial ALS (FALS) patients with superoxide dismutase 1 (SOD1) mutation and whole exome sequencing on 46 sporadic ALS (SALS) patients living in Hong Kong and found that 67% had at least 1 rare variant in the exons of 40 ALS genes; 22% had 2 or more. Patients with 2 or more rare variants had lower probability of survival than patients with 0 or 1 variant (p = 0.

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Background: Antiplatelet resumption in patients who developed intracerebral hemorrhage (ICH) while on antiplatelet therapy (antiplatelet-related ICH) represents an important medical dilemma. We aimed to study the long-term cardiovascular outcomes of antiplatelet-related ICH survivors, and the risk of recurrent ICH with antiplatelet resumption.

Methods: This was an observational study of 109 antiplatelet-related ICH survivors.

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Objective: In patients with TIA and ischemic stroke, we validated the total small vessel disease (SVD) score by determining its prognostic value for recurrent stroke.

Methods: Two independent prospective studies were conducted, one comprising predominantly Caucasian patients with TIA/ischemic stroke (Oxford Vascular Study [OXVASC]) and one predominantly Chinese patients with ischemic stroke (University of Hong Kong [HKU]). Cerebral MRI was performed and assessed for lacunes, microbleeds, white matter hyperintensities (WMH), and perivascular spaces (PVS).

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Aging, genetics and environmental toxicity are important etiological factors in Parkinson's disease (PD). However, its pathogenesis remains unclear. A major obstacle is the lack of an appropriate experimental model which incorporates genetic susceptibility, aging and prolonged environmental toxicity.

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