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Dive into the research topics where Simon Chiu is active.

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Featured researches published by Simon Chiu.


Journal of Complementary and Integrative Medicine | 2013

Liposomal-formulated curcumin [Lipocurc™] targeting HDAC (Histone Deacetylase) prevents apoptosis and improves motor deficits in Park 7 (DJ-1)-knockout rat model of Parkinson’s disease: implications for epigenetics-based nanotechnology-driven drug platform

Simon Chiu; Kristen Terpstra; Yves Bureau; Jirui Hou; Hana Raheb; Zack Cernvosky; Vladimir Badmeav; John Copen; Mariwan Husni; Michael Woodbury-Farina

Abstract Background: Converging evidence suggests dysregulation of epigenetics in terms of histone-mediated acetylation/deacetylation imbalance in Parkinson’s disease (PD). Targeting histone deacetylase (HDAC) in neuronal survival and neuroprotection may be beneficial in the treatment and prevention of neurodegenerative disorders. Few pharmacological studies use the transgenic model of PD to characterize the neuroprotection actions of a lead compound known to target HDAC in the brain. Methods: In our study, we investigated neuroprotective effects of liposomal-formulated curcumin: Lipocurc™ targeting HDAC inhibitor in the DJ-1(Park 7)-gene knockout rat model of PD. Group I (DJ-1-KO-Lipocurc™) received Lipocurc™ 20 mg/kg iv 3× weekly for 8 weeks; Group II: DJ-1 KO controls (DJ-1 KO-PBS) received i.v. phosphate-buffered saline (PBS). Group III: DJ-1-Wild Type (DJ-1 WT-PBS) received PBS. We monitored various components of motor behavior, rotarod, dyskinesia, and open-field behaviors, both at baseline and at regular intervals. Toward the end of the 8 weeks, we measured neuronal apoptosis and dopamine (DA) neuron-specific tyrosine hydroxylase levels by immunohistochemistry methods at post-mortem. Results: We found that DJ-KO Group I and Group II, as compared with DJ-1 WT group, exhibited moderate degree of motor impairment on the rotarod test. Lipocurc™ treatment improved the motor behavior motor impairment to a greater extent than the PBS treatment. There was marked apoptosis in the DJ-1 WT group. Lipocurc™ significantly blocked neuronal apoptosis: the apoptotic index of DJ-1-KO-Lipocurc™ group was markedly reduced compared with the DJ-KO-PBS group (3.3 vs 25.0, p<0.001). We found preliminary evidence Lipocurc™ stimulated DA neurons in the substantia nigra. The ratio of immature to mature DA neurons in substantia nigra was statistically higher in the DJ-1-KO-Lipocurc™ group (p<0.025). Conclusions: We demonstrated for the first time Lipocurc™’s anti-apoptotic and neurotrophic effects in theDJ-1-KO rat model of PD. Our promising findings warrant randomized controlled trial of Lipocurc™ in translating the novel nanotechnology-based epigenetics-driven drug discovery platform toward efficacious therapeutics in PD.


Psychiatric Clinics of North America | 2014

The Role of Nutrient-Based Epigenetic Changes in Buffering Against Stress, Aging, and Alzheimer’s Disease

Simon Chiu; Michel A. Woodbury-Fariña; Mujeeb U. Shad; Mariwan Husni; John Copen; Yves Bureau; Zack Z. Cernovsky; J. Jurui Hou; Hana Raheb; Kristen Terpstra; Veronica Sanchez; Ana Hategan; Mike Kaushal; Robbie Campbell

Converging evidence identifies stress-related disorders as putative risk factors for Alzheimer Disease (AD). This article reviews evidence on the complex interplay of stress, aging, and genes-epigenetics interactions. The recent classification of AD into preclinical, mild cognitive impairment, and AD offers a window for intervention to prevent, delay, or modify the course of AD. Evidence in support of the cognitive effects of epigenetics-diet, and nutraceuticals is reviewed. A proactive epigenetics diet and nutraceuticals program holds promise as potential buffer against the negative impact of aging and stress responses on cognition, and can optimize vascular, metabolic, and brain health in the community.


Evidence-based Complementary and Alternative Medicine | 2014

Proof-of-Concept Randomized Controlled Study of Cognition Effects of the Proprietary Extract Sceletium tortuosum (Zembrin) Targeting Phosphodiesterase-4 in Cognitively Healthy Subjects: Implications for Alzheimer’s Dementia

Simon Chiu; Nigel Gericke; Michel Farina-Woodbury; Vladimir Badmaev; Hana Raheb; Kristen Terpstra; Joalex Antongiorgi; Yves Bureau; Zack Z. Cernovsky; Jirui Hou; Veronica Sanchez; Marissa Williams; John Copen; Mariwan Husni; Liz Goble

Introduction. Converging evidence suggests that PDE-4 (phosphodiesterase subtype 4) plays a crucial role in regulating cognition via the PDE-4-cAMP cascade signaling involving phosphorylated cAMP response element binding protein (CREB). Objective. The primary endpoint was to examine the neurocognitive effects of extract Sceletium tortuosum (Zembrin) and to assess the safety and tolerability of Zembrin in cognitively healthy control subjects. Method. We chose the randomized double-blind placebo-controlled cross-over design in our study. We randomized normal healthy subjects (total n = 21) to receive either 25 mg capsule Zembrin or placebo capsule once daily for 3 weeks, in a randomized placebo-controlled 3-week cross-over design. We administered battery of neuropsychological tests: CNS Vital Signs and Hamilton depression rating scale (HAM-D) at baseline and regular intervals and monitored side effects with treatment emergent adverse events scale. Results. 21 subjects (mean age: 54.6 years ± 6.0 yrs; male/female ratio: 9/12) entered the study. Zembrin at 25 mg daily dosage significantly improved cognitive set flexibility (P < 0.032) and executive function (P < 0.022), compared with the placebo group. Positive changes in mood and sleep were found. Zembrin was well tolerated. Conclusion. The promising cognitive enhancing effects of Zembrin likely implicate the PDE-4-cAMP-CREB cascade, a novel drug target in the potential treatment of early Alzheimers dementia. This trial is registered with ClinicalTrials.gov NCT01805518.


international journal high risk behaviors & addiction | 2016

Body Composition Changes Associated With Methadone Treatment

Gamal Sadek; Simon Chiu; Zack Z. Cernovsky

Background: Methadone is associated with a statistically significant increase in BMI in the first 2 years of treatment. Objectives: To evaluate the changes of body composition (bone mass, % fat, % muscle mass, % water, and basal metabolic rate) related to this increase. Patients and Methods: Changes in body composition were monitored, via bioelectrical impedance, in 29 patients in methadone treatment for opiate dependency (age 18 to 44, mean = 29.3, SD = 7.0, 13 men, 16 women). Results: Within one year from admission to treatment, a statistically significant (t-tests, P < 0.05) increase was noted in their body mass index (BMI), % of body fat, average body mass, and average basal metabolic rate, and relative decrease in their % of muscle mass and % of bone mass. Neither absolute bone mass nor muscle mass changed significantly. Conclusions: Physicians involved in care of methadone patients should recommend dietary and lifestyle changes to improve their overall health.


MOJ Addiction Medicine & Therapy | 2017

Shall we Screen for Cardio-Metabolic Risks in Methadone and Buprenorphine Treatment for Opiate Dependence?

Simon Chiu; Gamal Sadek; Larry Lalone; Zack Cernovksy; Hana Raheb; Kristen Terpstra; John Copen; Mariwan Hunsi; Sidhu G; Andrew Sidhu; Autumn Carrier; Zahra Khazaeipool; Christina Chehade

Recent evidence suggests that buprenorphine, the partial opiate receptor agonist, exhibits equal efficacy as methadone in reducing withdrawal and craving for opiates in opioid dependence. Very few studies examine the benefits of screening for combined cardiovascular and metabolic risk factors in methadone and buprenorphine maintenance options for opioid dependence. We explore the feasibility whether outcome maybe improved through developing cardio-metabolic screening strategy in treatment facilities for opioid addiction.


Journal of Systems and Integrative Neuroscience | 2017

Exploratory study of sublimed sulfur, in cognitively normal subjects and in Alzheimer’s dementia (AD) subjects: implications for Sulfur targeting Hydrogen sulfide (H2S)/Homocysteine (Hcy) and beta-galactosidase (GALAC)/Autophagy Signaling in AD

Simon Chiu; Airudin Sulaiman Khan; Vladimir Badmaev; Kristen Terpstra; Zack Z. Cernovsky; Josh Varghese; Zahra Khazaeipool; Hana Elias; Autumn Carriere; Mariwan Husni; John Copen; Mujeeb U. Shad; Michel Farina Woodbury; Ann Johnson; Christina Chehade

Introduction: There is mounting evidence to suggest that hyper-homocysteinemia (eHct) correlates with cognitive decline severity and cortical atrophy in AD. Hydrogen Sulfide (H2S) exerts neuroprotection through regulating Homocysteine (eHcy) signaling. Elemental sulfur can mediate H2S neuroprotection through the trans-sulfuration pathway and correct the the dysregulation of H2S /Hct signaling in AD. Sublimed Sulfur, formulated as SULMEDOL and approved for the treatment of lactose intolerance, activates gut beta-galactosidase (GALAC). We repurpose Sulmedol from lactose intolerance to likely CNS effect, since gut GALAC crosstalks with senescence-related GALAC expression in the brain. In view of the known regulatory function of GALAC in CNS endosomal-lysosomal autophagy system , we propose that SULMEDOL may rescue aberrant autophagy in AD. Methods: We hypothesize that sublimed Sulfur (SS), via targeting H2S/Hcy and GALAC, may be efficacious in AD. In study I, we examined the 30-day treatment effects of SS at daily dosage of 200 mg to be administered at in altering the plasma Hcy levels in a small cohort of cognitive normal subjects. We stratified the cohort of cognitively normal control subjects to be administered SS into three groups with pre-determined range of basal fHCy levels as follows: Group 1 (n=16): range of fHcy 10.0-22.1 μmol/L; Group 2(n=15) fHcy range:7.1-9.9 μmol/L;Group 3 (n=15); range of fHcy 2.3-7.0 μmol/L . Primary outcome was defined as change in Hcy from baseline to 24-hr and 30-day post-treatment period. In study II, we evaluated the safety and tolerability of SS in two AD patients were treated with 200 mg for 3 months, with Clinical Global Impression–Global Improvement (CGI –I) scale as the primary outcome measure. Results: In Study I, Group I subjects, fHcy decreased significantly by 36.1%, 24 hours after treatment and by 29.3%, 30 days later.In Group 2 fHcy did not change significantly. Group 3 exhibited paradoxical non-significant increase in fHcy, without change in erythrocyte folic acid, serum lipids and vitamin B12. SS was well tolerated in all patients. In Study II, clinical vignette analysis of two AD patients revealed that 3-month SS treatment ameliorated cluster of AD symptoms: nocturnal wandering, paranoid delusions, disorientation and confusion. CGI-I scale score was “very much improved”. No serious adverse events were reported. Conclusions: SS in dual targeting H2S-homocysteine inflammation signaling and GALAC autophagy pathway related to AD, holds promise in therapeutic development of AD. Our findings warrant controlled trial of SS in AD. Correspondence to: Lawson Health Research Institute, London Ontario; University Western Ontario, London, ON, Canada; Parkwood Mental Health Institute, St Joseph Health Care, London ON, Canada, E-mail: schiu3207@ rogers.com


Journal of Clinical Epigenetics | 2017

Targeting Epigenetics Signaling with Curcumin: A Transformative Drug Lead in Treatment of Schizophrenia?

Simon Chiu; Michel A. Woodbury-Fariña; Kristen Terpstra; Vladimir Badmaev; Zack Z. Cernovsky; Yves Bureau; Jerry Jirui; Hana Raheb; Mariwan Husn; John Copen; Mujeeb U. Shad; Amresh Srivastava; Veronica Sanchez; Marissa Williams; Zahra Khazaeipool; Autumn Carriere; Christina Chehade

Despite advances in pharmacotherapy, schizophrenia continues to carry a high societal disease burden related to positive and negative symptoms, and neurocognitive deficits and severe functional impairment. Findings from epigenetics have yet to translate the epigenetics targets to efficacious drug therapy. We review the repertoire of CNS pharmacology of curcumin derived from Curcuma Longa, commonly known as “turmeric”: the well-known curry extract. We highlight the body of evidence in support of the emerging role of curcumin as a panhistone deacetylase (HDAC) inhibitor regulating the expression of genes involved in inflammation and NMDA N-methyl-aspartic acid (NMDA)-glutamate systems, as related to schizophrenia. Based on the findings from translational studies of curcumin extracts, curcumin C-3 complex formulation (Supercurcumin™) and patented liposome-based curcumin (Lipocurc™), we propose that intravenous infusion of Lipocurc™ holds promise as the novel drug lead and preferred targeted brain delivery mode in reprogramming faculty epigenetics network and in remodeling restrictive chromatin configuration in schizophrenia. Phase II/Phase III epigenetics-biomarker-based randomized placebo-controlled trials in treatment resistant schizophrenia are warranted. Our approach of intravenous infusion of Lipocurc™ behaving as pan HDAC inhibitor represents a new paradigm of drug development in combining targeting epigenetics footprints with brain-specific drug delivery system in schizophrenia. Lipocurc™ can open the Pandora box in unexplored therapeutics vistas in modifying the phenotype of treatment resistant schizophrenia.


Mental Illness | 2015

Psychopathology and Urine Toxicology in Methadone Patients.

Gamal Sadek; Zack Z. Cernovsky; Simon Chiu

Several studies reported high rates of psychiatric commorbidity among methadone patients. We examined the relationships of measures of psychopathology to outcomes of screening urine tests for cocaine, opiates, and benzodiazepines in a sample of 56 methadone patients. They also completed the Symptom Check List-90-Revised (SCL-90-R). The highest scales in the SCL-90-R profile of our patients were those indicating somatic discomfort, anger, phobic anxiety, paranoid ideation, and also obsessive-compulsive disorder symptoms (scores above the 39th percentile). The only significant correlations between urine tests and SCL-90-R psychopathology were those involving benzodiazepines: patients with urine tests positive for benzodiazepines had lower social self-confidence (r=0.48), were more obsessive-compulsive (r=0.44), reported a higher level of anger (r=0.41), of phobic tendencies (r=40), of anxiety (r=0.39), and of paranoid tendencies (r=0.38), and also reported more frequent psychotic symptoms (r=0.43).


International Journal of Mental Health & Psychiatry | 2015

Exploring Zembrin Extract Derived from South African Plant, Sceletium tortuosum in Targeting cAMP-driven Phosphodiesterase (PDE) Signaling in Alzheimer’s Disease: Synthesis of Evidence

Simon Chiu; Hana Raheb; Kristen Terpstra; JoshVaughan; Michel Farina-Woodbury; Yves Bureau; Zack Z. Cernovsky; Jirui Hou; John Copen; Mariwan Husni; Vladimir Badmeav; Ana Hategan; Mujeeb U. Shad; Zach Suntras; Nigel Gericke

Recently with the changing landscape of the aging population and the increase in incidence of Alzheimer’s disease (AD), there has been marked interest to develop strategies to prevent, delay and modify AD. We review the diverse lines of evidence in support of the emerging role of cAMP-mediated Phosphodiesterase (PDE) signalling with respect to aging, inflammation and depression. In view of the link of PDE to Epigenetic complex, targeting PDE through designing modulators and inhibitors of PDE may represent a novel approach in AD therapeutics. We review critically the translational studies of the proprietary Zembrin extract harvested and processed from the South African plant, Sceletium tortuosum, highlighting the dual property of Zembrin in targeting coupling of PDE and serotonin signaling mechanisms in vitro and in vivo models of AD and cognition. The promising clinical findings of Zembrin in cognition suggest that Zembrin extract may merit randomized controlled trials in AD to establish the efficacy and safety in AD.


Comprehensive Psychology | 2015

Correlates of Loitering at a Methadone Clinic

Zack Z. Cernovsky; Yves Bureau; Simon Chiu; Gamal Sadek

Abstract An eight-item questionnaire was administered to 55 patients of a Canadian methadone clinic (34 men, 21 women) to self-rate their desire to relax in or around the clinic, chat with peers, enjoy the sense of community with fellow addicts, and rate the relative importance they may attribute to this part of their daily routine. Total score for loitering tendency was significantly correlated to scores on the Alcohol Use Disorders Identification Test (r = .39) and on the Drug Abuse Screening Test (r = .29) but not to results of urine tests for cocaine, opiates, and benzodiazepines, or to the psychopathology scales of the Symptom Checklist-90–Revised, or to age or sex. The loitering may express an unmet need for peer support.

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Zack Z. Cernovsky

University of Western Ontario

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John Copen

Vancouver Island Health Authority

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Yves Bureau

University of Western Ontario

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Gamal Sadek

University of Western Ontario

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Hana Raheb

Lawson Health Research Institute

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Mujeeb U. Shad

University of Texas Southwestern Medical Center

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Zahra Khazaeipool

University of Western Ontario

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Autumn Carriere

University of Western Ontario

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