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1.
Arch Gerontol Geriatr ; 125: 105523, 2024 Oct.
Article in English | MEDLINE | ID: mdl-38878671

ABSTRACT

AIM: The World Falls Guidelines (WFG) Task Force published a falls risk stratification algorithm in 2022. However, its adaptability is uncertain in low- and middle-income settings such as Malaysia due to different risk factors and limited resources. We evaluated the effectiveness of the WFG risk stratification algorithm in predicting falls among community-dwelling older adults in Malaysia. METHODS: Data from the Malaysian Elders Longitudinal Research subset of the Transforming Cognitive Frailty into Later-Life Self-Sufficiency cohort study was utilized. From 2013-2015, participants aged ≥55 years were selected from the electoral rolls of three parliamentary constituencies in Klang Valley. Risk categorisation was performed using baseline data. Falls prediction values were determined using follow-up data from wave 2 (2015-2016), wave 3 (2019) and wave 4 (2020-2022). RESULTS: Of 1,548 individuals recruited, 737 were interviewed at wave 2, 858 at wave 3, and 742 at wave 4. Falls were reported by 13.4 %, 29.8 % and 42.9 % of the low-, intermediate- and high-risk groups at wave 2, 19.4 %, 25.5 % and 32.8 % at wave 3, and 25.8 %, 27.7 % and 27.0 % at wave 4, respectively. At wave 2, the algorithm generated a sensitivity of 51.3 % (95 %CI, 43.1-59.2) and specificity of 80.1 % (95 %CI, 76.6-83.2). At wave 3, sensitivity was 29.4 % (95 %CI, 23.1-36.6) and specificity was 81.6 % (95 %CI, 78.5-84.5). At wave 4, sensitivity was 26.0 % (95 %CI, 20.2-32.8) and specificity was 78.4 % (95 %CI, 74.7-81.8). CONCLUSION: The algorithm has high specificity and low sensitivity in predicting falls, with decreasing sensitivity over time. Therefore, regular reassessments should be made to identify individuals at risk of falling.


Subject(s)
Accidental Falls , Algorithms , Humans , Accidental Falls/statistics & numerical data , Accidental Falls/prevention & control , Male , Aged , Female , Malaysia/epidemiology , Risk Assessment/methods , Middle Aged , Independent Living/statistics & numerical data , Risk Factors , Geriatric Assessment/methods , Aged, 80 and over , Cohort Studies , Predictive Value of Tests , Longitudinal Studies , Frailty/diagnosis , Frailty/epidemiology
2.
Ageing Res Rev ; 82: 101744, 2022 12.
Article in English | MEDLINE | ID: mdl-36202312

ABSTRACT

This systematic review appraised previous findings on differential gut microbiota composition and intestinal permeability markers between frail and healthy older adults. A literature search was performed using PubMed, Scopus, ScienceDirect and the Cochrane Library. Relevant studies were shortlisted based on inclusion and exclusion criteria as well as assessed for risk of bias. The primary outcome was the differential composition of gut microbiota and/ or intestinal permeability markers between frail and healthy older adults. A total of 10 case-control studies and one cohort study were shortlisted. Based on consistent findings reported by more than one shortlisted study, the microbiota of frail older adults was characterised by decreased phylum Firmicutes, with Dialister, Lactobacillus and Ruminococcus being the prominent genera. Healthy controls, on the other hand, exhibited higher Eubacterium at the genera level. In terms of intestinal permeability, frail older adults were presented with increased serum zonulin, pro-inflammatory cytokines (TNF-α, HMGB-1, IL-6, IL1-ra, MIP-1ß) and amino acids (aspartic acid and phosphoethanolamine) when compared to healthy controls. Altogether, frail elderlies had lower gut microbiota diversity and lower abundance of SCFA producers, which may have led to leaky guts, upregulated pro-inflammatory cytokines, frailty and sarcopenia.


Subject(s)
Gastrointestinal Microbiome , Humans , Aged , Frail Elderly , Cohort Studies , Permeability , Biomarkers , Cytokines
3.
Brain Res Bull ; 190: 218-233, 2022 11.
Article in English | MEDLINE | ID: mdl-36228872

ABSTRACT

In order to understand the biological processes underlying dopaminergic neurons (DpN) regeneration in a 6-hydroxydopamine(6-OHDA)-induced adult zebrafish-based Parkinson's disease model, this study investigated the specific phases of neuroregeneration in a time-based manner. Bromodeoxyuridine (BrdU) was administered 24 h before the harvest of brain tissues at day three, five, seven, nine, 12 and 14 postlesion. Potential migration of proliferative cells was tracked over 14 days postlesion through double-pulse tracking [BrdU and 5-ethynyl-2'-deoxyuridine (EdU)] of cells and immunohistostaining of astrocytes [glial fibrillary acidic protein (GFAP)]. Gene expression of foxa2 and nurr1 (nr4a2a) at day three, nine, 14, 18, 22 and 30 postlesion was quantified using qPCR. Protein expression of foxa2 at day three, seven, 14 and 22 postlesion was validated using the western blot technique. Double labelling [EdU and tyrosine hydroxylase (TH)] of proliferative cells was performed to ascertain their fate after the neuroregeneration processes. It was found that whilst cell proliferation remained unchanged in the area of substantial DpN loss, the ventral diencephalon (vDn), there was a transient increase of cell proliferation in the olfactory bulb (OB) and telencephalon (Tel) seven days postlesion. BrdU-immunoreactive (ir)/ EdU-ir cells and activated astrocytes were later found to be significantly increased in the vDn and its nearby area (Tel) 14 days postlesion. There was a significant but transient downregulation of foxa2 at day three and nine postlesion, and nr4a2a at day three, nine and 14 postlesion. The expression of both genes remained unchanged in the OB and Tel. There was a transient downregulation of foxa2 protein expression at day three and seven postlesion. The significant increase of EdU-ir/ TH-ir cells in the vDn 30 days postlesion indicates maturation of proliferative cells (formed between day five-seven postlesion) into DpN. The present findings warrant future investigation of critical factors that govern the distinctive phases of DpN regeneration.


Subject(s)
Dopaminergic Neurons , Olfactory Bulb , Animals , Brain/metabolism , Bromodeoxyuridine/metabolism , Diencephalon/metabolism , Dopaminergic Neurons/metabolism , Nerve Regeneration/physiology , Olfactory Bulb/metabolism , Oxidopamine , Telencephalon , Tyrosine 3-Monooxygenase/metabolism , Zebrafish/metabolism
4.
J Alzheimers Dis ; 82(2): 673-687, 2021.
Article in English | MEDLINE | ID: mdl-34092633

ABSTRACT

BACKGROUND: Cognitive frailty (CF) is identified as one of the main precursors of dementia. Multidomain intervention has been found to delay or prevent the onset of CF. OBJECTIVE: The aim of our present study is to determine the effectiveness of a comprehensive, multidomain intervention on CF; to evaluate its cost effectiveness and the factors influencing adherence toward this intensive intervention. METHODS: A total of 1,000 community dwelling older adults, aged 60 years and above will be screened for CF. This randomized controlled trial involves recruitment of 330 older adults with CF from urban, semi-urban, and rural areas in Malaysia. Multidomain intervention comprised of physical, nutritional, cognitive, and psychosocial aspects will be provided to participants in the experimental group (n = 165). The control group (n = 165) will continue their usual care with their physician. Primary outcomes include CF status, physical function, psychosocial and nutritional status as well as cognitive performance. Vascular health and gut microbiome will be assessed using blood and stool samples. A 24-month intensive intervention will be prescribed to the participants and its sustainability will be assessed for the following 12 months. The effective intervention strategies will be integrated as a personalized telerehabilitation package for the reversal of CF for future use. RESULTS: The multidomain intervention developed from this trial is expected to be cost effective compared to usual care as well as able is to reverse CF. CONCLUSION: This project will be part of the World-Wide FINGERS (Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability) Network, of which common identifiable data will be shared and harmonized among the consortia.


Subject(s)
Cognition/physiology , Cognitive Dysfunction , Diet, Healthy/methods , Frail Elderly/psychology , Physical Functional Performance , Preventive Health Services , Psychosocial Intervention/methods , Aged , Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/physiopathology , Cognitive Dysfunction/prevention & control , Cognitive Dysfunction/psychology , Cost-Benefit Analysis , Female , Humans , Independent Living , Male , Mass Screening/methods , Preventive Health Services/economics , Preventive Health Services/methods , Program Evaluation , Randomized Controlled Trials as Topic , Telerehabilitation/methods
5.
J Diet Suppl ; 18(6): 655-681, 2021.
Article in English | MEDLINE | ID: mdl-33962540

ABSTRACT

Neuroinflammation is associated with neuronal cell death and could lead to chronic neurodegeneration. This study investigated the neuroprotective potential of virgin coconut oil (VCO) against lipopolysaccharide (LPS)-induced cytotoxicity of neuroblastoma SK-N-SH cells. The findings were validated using Wistar rats, which were fed with 1-10 g/kg VCO for 31 days, exposed to LPS (0.25 mg/kg) and subjected to the Morris Water Maze Test. Brain homogenate was subjected to biochemical analyses and gene expression studies. α-Tocopherol (α-T; 150 mg/kg) served as the positive control. VCO (100 µg/mL) significantly (p < 0.01) improved SK-N-SH viability (+57%) and inhibited reactive oxygen species (-31%) in the presence of LPS. VCO (especially 10 g/kg) also significantly (p < 0.05) enhanced spatial memory of LPS-challenged rats. Brain homogenate of VCO-fed rats was presented with increased acetylcholine (+33%) and reduced acetylcholinesterase (-43%). The upregulated antioxidants may have reduced neuroinflammation [malondialdehyde (-51%), nitric oxide (-49%), Cox-2 (-64%) and iNos (-63%)] through upregulation of IL-10 (+30%) and downregulation of IL-1ß (-65%) and Interferon-γ (-25%). There was also reduced expression of Bace-1 (-77%). VCO-induced neuroprotection, which was comparable to α-T, could be mediated, in part, through inflammatory, cholinergic and amyloidogenic pathways.


Subject(s)
Lipopolysaccharides , Neuroprotection , Acetylcholinesterase , Animals , Anti-Inflammatory Agents/pharmacology , Cholinergic Agents/pharmacology , Coconut Oil , Lipopolysaccharides/pharmacology , Oxidative Stress , Rats , Rats, Wistar
6.
Neurotox Res ; 39(2): 504-532, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33141428

ABSTRACT

Parkinson's disease (PD) is the second most common neurodegenerative disease. The etiology of PD remains an enigma with no available disease modifying treatment or cure. Pharmacological compensation is the only quality of life improving treatments available. Endogenous dopaminergic neuroregeneration has recently been considered a plausible therapeutic strategy for PD. However, researchers have to first decipher the complexity of adult endogenous neuroregeneration. This raises the need of animal models to understand the underlying molecular basis. Mammalian models with highly conserved genetic homology might aid researchers to identify specific molecular mechanisms. However, the scarcity of adult neuroregeneration potential in mammals obfuscates such investigations. Nowadays, non-mammalian models are gaining popularity due to their explicit ability to neuroregenerate naturally without the need of external enhancements, yet these non-mammals have a much diverse gene homology that critical molecular signals might not be conserved across species. The present review highlights the advantages and disadvantages of both mammalian and non-mammalian animal models that can be essentially used to study the potential of endogenous DpN regeneration against PD.


Subject(s)
Brain/physiopathology , Disease Models, Animal , Dopaminergic Neurons/physiology , Nerve Regeneration , Parkinson Disease/physiopathology , Animals , Humans
7.
Ageing Res Rev ; 60: 101066, 2020 07.
Article in English | MEDLINE | ID: mdl-32294542

ABSTRACT

In order to gauge the impact of proteomics in discovery of Alzheimer's disease (AD) blood-based biomarkers, this study had systematically reviewed articles published between 1984-2019. Articles that fulfilled the inclusion criteria were assessed for risk of bias. A meta-analysis was performed for replicable candidate biomarkers (CB). Of the 1651 articles that were identified, 17 case-control and two cohort studies, as well as three combined case-control and longitudinal designs were shortlisted. A total of 207 AD and mild cognitive impairment (MCI) CB were discovered, with 48 reported in >2 studies. This review highlights six CB, namely alpha-2-macroglobulin (α2M)ps, pancreatic polypeptide (PP)ps, apolipoprotein A-1 (ApoA-1)ps, afaminp, insulin growth factor binding protein-2 (IGFBP-2)ps and fibrinogen-γ-chainp, all of which exhibited consistent pattern of regulation in >three independent cohorts. They are involved in AD pathogenesis via amyloid-beta (Aß), neurofibrillary tangles, diabetes and cardiovascular diseases (CVD). Meta-analysis indicated that ApoA-1ps was significantly downregulated in AD (SMD = -1.52, 95% CI: -1.89, -1.16, p < 0.00001), with low inter-study heterogeneity (I2 = 0%, p = 0.59). α2Mps was significantly upregulated in AD (SMD = 0.83, 95% CI: 0.05, 1.62, p = 0.04), with moderate inter-study heterogeneity (I2 = 41%, p = 0.19). Both CB are involved in Aß formation. These findings provide important insights into blood-based AD biomarkers discovery via proteomics.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Proteomics , Alzheimer Disease/diagnosis , Biomarkers/analysis , Cognitive Dysfunction/diagnosis , Cohort Studies , Humans
8.
J Pharm Biomed Anal ; 178: 112909, 2020 Jan 30.
Article in English | MEDLINE | ID: mdl-31618702

ABSTRACT

A high-performance thin-layer chromatography (HPTLC) method combined with effect-directed-analysis (EDA) was developed to screen the antioxidant, neuroprotective and antidiabetic effects in essential oils derived from lavender flower, lemon myrtle, oregano, peppermint, sage, and rosemary leaves (Lamiaceae family). HPTLC hyphenated with microchemical (DPPH•, p-anisaldehyde, and ferric chloride) derivatizations, was used to evaluate antioxidant activity, presence of phytosterols and terpenoids, and polyphenolic content, while the combination with biochemical (α-amylase and acetylcholine esterase (AChE) enzymatic) derivatizations was used to asses α-amylase and AChE inhibitory activities. The superior antioxidant activity of oregano leaf extract is attributed to the presence of high levels of aromatic compounds, like polyphenolic acids. The strongest α-amylase inhibition was observed in lemon myrtle and rosemary plus extracts due to the presence of monoterpenes. Rosemary and sage extracts exhibit the highest AChE inhibition activity, with 1 µL essential oils being more potent than the recommended daily dose of donepezil. This superior neuroprotection was attributed to the presences of di- and triterpenes that displayed strong AChE inhibition and antioxidant potential in DPPH• free radical assay. Antioxidant activity was related to phenolic content (R = 0.49), while α-amylase inhibitory activity was positively related to antioxidant activity (R = 0.20) and terpenoid/sterol content (R = 0.31). AChE inhibitory activity was correlated (R = 0.80) to the combined effect of phenolics and terpenoids. Thus, the superior AChE inhibitory and neuroprotection potential of rosemary and sage essential oils could be attributed to joint effects of main phenolic and terpene constituents. The hyphenated HPTLC method provided rapid bioanalytical profiling of highly complex essential oil samples.


Subject(s)
Chromatography, High Pressure Liquid/methods , Chromatography, Thin Layer/methods , Hypoglycemic Agents/chemistry , Lamiaceae/chemistry , Neuroprotective Agents/chemistry , Oils, Volatile/chemistry , Acetylcholinesterase/metabolism , Antioxidants/chemistry , Antioxidants/pharmacology , Biological Assay/methods , Biphenyl Compounds/chemistry , Biphenyl Compounds/pharmacology , Cholinesterase Inhibitors/chemistry , Cholinesterase Inhibitors/pharmacology , Hypoglycemic Agents/pharmacology , Neuroprotective Agents/pharmacology , Oils, Volatile/pharmacology , Phenols/chemistry , Phenols/pharmacology , Plant Extracts/chemistry , Plant Extracts/pharmacology , Terpenes/chemistry , Terpenes/pharmacology , alpha-Amylases/metabolism
9.
Drug Deliv Transl Res ; 9(2): 578-594, 2019 04.
Article in English | MEDLINE | ID: mdl-29594914

ABSTRACT

Carbon nanotubes (CNTs) possess outstanding properties that could be useful in several technological, drug delivery, and diagnostic applications. However, their unique physical and chemical properties are hindered due to their poor solubility. This article review's the different ways and means of solubility enhancement of single-wall carbon nanotubes (SWNTs). The advantages of SWNTs over the multi-walled carbon nanotubes (MWNTs) and the method of non-covalent modification for solubility enhancement has been the key interest in this review. The review also highlights a few examples of dispersant design. The review includes some interesting utility of SWNTs being wrapped with polymer especially in biological media that could mediate proper drug delivery to target cells. Further, the use of wrapped SWNTs with phospholipids, nucleic acid, and amphiphillic polymers as biosensors is of research interest. The review aims at summarizing the developments relating to wrapped SWNTs to generate further research prospects in healthcare.


Subject(s)
Nanotubes, Carbon , Polymers , Animals , Humans , Hydrophobic and Hydrophilic Interactions , Nanomedicine , Nanotubes, Carbon/chemistry , Polymers/administration & dosage , Polymers/chemistry , Solubility
10.
Exp Anim ; 68(1): 113-124, 2019 Feb 26.
Article in English | MEDLINE | ID: mdl-30393276

ABSTRACT

Chronic stress has been associated with impairment of memory, learning, and social cognition. In animal studies, chronic stress has been shown to impair rodent sociability behaviour which mimics social withdrawal as observed in depression patients. The effect of chronic stress on social recognition, however, is uncertain. Moreover, with reference to spatial learning and memory, the effect of chronic stress is dependent on the type of behavioural task: an appetitively or aversively motivated tasks. The effect of chronic stress was consistent in impairing spatial learning and memory in the appetitive task; however, the effect was inconsistent in an aversive task like the Morris water maze. Thus, we aimed to investigate the effect of chronic restraint stress on sociability and social recognition by using a modified protocol of the three-chamber paradigm and the effect of chronic restraint stress on spatial learning and memory by using the Morris water maze test in young adult C57BL/6J male mice. The present report also describes a modified protocol of the three-chamber paradigm. Our modification is based on measurement of sniffing behaviour, which is a direct social interaction that represents sociability. We used the chronic restraint stress paradigm for 6 h/day for 21 days to induce depression-like symptoms in male C57BL/6J mice which were validated by forced-swim test. We observed that the stressed group had impairments in their sociability behaviour but that social recognition was not affected. Furthermore, we confirmed that chronic stress produced no significant impairment in spatial learning and memory of the mice in the water maze.


Subject(s)
Behavior, Animal , Cognition Disorders/etiology , Cognition Disorders/psychology , Learning Disabilities/etiology , Learning Disabilities/psychology , Memory Disorders/etiology , Memory Disorders/psychology , Social Behavior , Spatial Memory , Stress, Psychological/complications , Stress, Psychological/psychology , Animals , Chronic Disease , Depression/etiology , Depression/psychology , Interpersonal Relations , Male , Maze Learning , Mice, Inbred C57BL , Recognition, Psychology , Time Factors
11.
Exp Anim ; 67(4): 421-429, 2018 Nov 01.
Article in English | MEDLINE | ID: mdl-29731492

ABSTRACT

Phencyclidine (PCP) has been used to model cognitive deficits related to schizophrenia in rats and mice. However, the model in mice is not consistent in terms of the PCP effective dose reported. Furthermore, most of the previous studies in mice excluded the presence of drug washout period in the regime. Thus, we aimed to optimize the dose of PCP in producing robust cognitive deficits by implementing it in a PCP regime which incorporates a drug washout period. The regimen used was 7 days' daily injection of PCP or saline for treatment and vehicle groups, respectively; followed by 24 h drug washout period. After the washout period, the test mice were tested in water maze (5 days of acquisition + 1 day of probe trial) for assessment of spatial learning and memory. Initially, we investigated the effect of PCP at 2mg/kg, however, no apparent impairment in spatial learning and memory was observed. Subsequently, we examined the effect of higher doses of PCP at 5, 10 and 20 mg/kg. We found that the PCP at 10 mg/kg produced a significant increase in "latency to reach the platform" during the acquisition days and a significant increase in "latency of first entry to previous platform" during the probe day. There was no significant change observed in "swim speed" during the test days. Thus, we concluded that PCP at 10 mg/kg produced robust deficits in spatial learning and memory without being confounded by motor disturbances.


Subject(s)
Excitatory Amino Acid Antagonists/adverse effects , Memory Disorders/chemically induced , Memory Disorders/psychology , Phencyclidine/adverse effects , Schizophrenic Psychology , Spatial Learning/drug effects , Spatial Memory/drug effects , Animals , Disease Models, Animal , Dose-Response Relationship, Drug , Excitatory Amino Acid Antagonists/administration & dosage , Male , Mice, Inbred C57BL , Phencyclidine/administration & dosage
12.
Pathog Glob Health ; 112(3): 123-131, 2018 05.
Article in English | MEDLINE | ID: mdl-29528265

ABSTRACT

Immunoinformatics plays a pivotal role in vaccine design, immunodiagnostic development, and antibody production. In the past, antibody design and vaccine development depended exclusively on immunological experiments which are relatively expensive and time-consuming. However, recent advances in the field of immunological bioinformatics have provided feasible tools which can be used to lessen the time and cost required for vaccine and antibody development. This approach allows the selection of immunogenic regions from the pathogen genomes. The ideal regions could be developed as potential vaccine candidates to trigger protective immune responses in the hosts. At present, epitope-based vaccines are attractive concepts which have been successfully trailed to develop vaccines which target rapidly mutating pathogens. In this article, we provide an overview of the current progress of immunoinformatics and their applications in the vaccine design, immune system modeling and therapeutics.


Subject(s)
Computational Biology/methods , Drug Discovery/methods , Epitopes/immunology , Immunity, Cellular , Immunity, Humoral , Vaccines/immunology , Vaccines/isolation & purification , Animals , Epitopes/genetics , Humans , Vaccines/genetics
13.
Curr Drug Deliv ; 15(1): 77-86, 2018.
Article in English | MEDLINE | ID: mdl-28322162

ABSTRACT

BACKGROUND: Categorized as a Biopharmaceutics Classification System (BCS) Class II drugs, statin exhibit low aqueous solubility and bioavailability thus presenting an obstacle and great challenge to formulation researchers. This paper describes a de novo approach to enhance the aqueous solubility of one of the most commonly prescribed statins i.e., simvastatin (SMV) by forming a complex (SMV-ARG) with cosolute arginine (ARG). METHODS: The complex has been characterized for its apparent solubility and in vitro dissolution. The solid state characterization has been carried out using Fourier Transform Infra-Red (FTIR) Spectroscopy, Elemental Analysis, X-Ray Powder Diffraction (XRD), Differential Scanning Calorimetry (DSC) analysis, Thermal Gravimetric Analysis (TGA) and Scanning Electron Microscopy (SEM). RESULTS: Simvastatin-Arginine (SMV-ARG) complex exhibited massive solubility enhancement by 12,000 fold and significant improvement in both acidic and alkaline dissolution media. A conversion of coherent crystalline to non-coherent pattern, and certain extent of amorphization in SMV-ARG complex, fully justifies the enhanced solubility, and hence the dissolution profile. CONCLUSION: The present study provides a significant evidence that ARG molecules are capable to form a complex with small molecules and increase their aqueous solubility which prove to be beneficial in drug formulation and development.


Subject(s)
Arginine/chemistry , Simvastatin/chemistry , Calorimetry, Differential Scanning , Hydrogen-Ion Concentration , Microscopy, Electron, Scanning , Powder Diffraction , Solubility , Temperature , Water/chemistry
14.
Neurotox Res ; 32(3): 496-508, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28707266

ABSTRACT

Conventional mammalian models of neurodegeneration are often limited by futile axonogenesis with minimal functional recuperation of severed neurons. The emergence of zebrafish, a non-mammalian model with excellent neuroregenerative properties, may address these limitations. This study aimed to establish an adult zebrafish-based, neurotoxin-induced Parkinson's disease (PD) model and subsequently validate the regenerative capability of dopaminergic neurons (DpN). The DpN of adult male zebrafish (Danio rerio) were lesioned by microinjecting 6-hydroxydopamine (6-OHDA) neurotoxin (6.25, 12.5, 18.75, 25, 37.5, 50 and 100 mg/kg) into the ventral diencephalon (Dn). This was facilitated by an optimised protocol that utilised 1,1'-dioctadecyl-3,3,3',3'-tetramethyl-indocarbocyanineperchlorate (DiI) dye to precisely identify the injection site. Immunostaining was utilised to identify the number of tyrosine hydroxylase immunoreactive (TH-ir) DpN in brain regions of interest (i.e. olfactory bulb, telencephalon, preoptic area, posterior tuberculum and hypothalamus). Open tank video recordings were performed for locomotor studies. The Dn was accessed by setting the injection angle of the microinjection capillary to 60° and injection depth to 1200 µm (from the exposed brain surface). 6-OHDA (25 mg/kg) successfully ablated >85% of the Dn DpN (preoptic area, posterior tuberculum and hypothalamus) whilst maintaining a 100% survival. Locomotor analysis of 5-min recordings revealed that 6-OHDA-lesioned adult zebrafish were significantly (p < 0.0001) reduced in speed (cm/s) and distance travelled (cm). Lesioned zebrafish showed full recovery of Dn DpN 30 days post-lesion. This study had successfully developed a stable 6-OHDA-induced PD zebrafish model using a straightforward and reproducible approach. Thus, this developed teleost model poses exceptional potentials to study DpN regeneration.


Subject(s)
Dopaminergic Neurons , Nerve Regeneration , Oxidopamine , Parkinsonian Disorders , Zebrafish , Animals , Brain/pathology , Brain/physiopathology , Cell Count , Dopaminergic Neurons/pathology , Dopaminergic Neurons/physiology , Dose-Response Relationship, Drug , Immunohistochemistry , Male , Microinjections , Microscopy, Confocal , Motor Activity , Nerve Regeneration/physiology , Oxidopamine/toxicity , Parkinsonian Disorders/pathology , Parkinsonian Disorders/physiopathology , Tyrosine 3-Monooxygenase/metabolism , Zebrafish Proteins/metabolism
15.
Life Sci ; 180: 23-35, 2017 Jul 01.
Article in English | MEDLINE | ID: mdl-28501482

ABSTRACT

AIM: The present study is aimed to investigate the ability of ciproxifan, a histamine H3 receptor antagonist to inhibit ß-amyloid (Aß)-induced neurotoxicity in SK-N-SH cells and APP transgenic mouse model. MATERIALS AND METHODS: In vitro studies was designed to evaluate the neuroprotective effects of ciproxifan in Aß25-35 - induced SK-N-SH cells. For the in vivo study, ciproxifan (1 and 3mg/kg, i.p.) was administrated to transgenic mice for 15days and behaviour was assessed using the radial arm maze (RAM). Brain tissues were collected to measure Aß levels (Aß1-40 and Aß1-42), acetylcholine (ACh), acetylcholinesterase (AChE), nitric oxide (NO), lipid peroxidation (LPO), antioxidant activities, cyclooxygenases (COX) and cytokines (IL-1α, IL-1ß and IL-6), while plasma was collected to measure TGF-1ß. RESULTS: The in vitro studies demonstrated neuroprotective effect of ciproxifan by increasing cell viability and inhibiting reactive oxygen species (ROS) in Aß25-35-induced SK-N-SH cells. Ciproxifan significantly improved the behavioural parameters in RAM. Ciproxifan however, did not alter the Aß levels in APP transgenic mice. Ciproxifan increased ACh and showed anti-oxidant properties by reducing NO and LPO levels as well as enhancing antioxidant levels. The neuroinflammatory analysis showed that ciproxifan reduced both COX-1 and COX-2 activities, decreased the level of pro-inflammatory cytokines IL-1α, IL-1ß and IL-6 and increased the level of anti-inflammatory cytokine TGF-1ß. CONCLUSION: This present study provides scientific evidence of the use of ciproxifan via antioxidant and cholinergic pathways in the management of AD.


Subject(s)
Alzheimer Disease/drug therapy , Histamine H3 Antagonists/pharmacology , Imidazoles/pharmacology , Neuroprotective Agents/pharmacology , Oxidative Stress/drug effects , Acetylcholine/metabolism , Alzheimer Disease/pathology , Amyloid beta-Peptides/metabolism , Animals , Antioxidants/metabolism , Cell Line, Tumor , Cytokines/metabolism , Disease Models, Animal , Dose-Response Relationship, Drug , Histamine H3 Antagonists/administration & dosage , Humans , Imidazoles/administration & dosage , Male , Maze Learning/drug effects , Mice , Mice, Transgenic , Neuroblastoma/metabolism , Neuroprotective Agents/administration & dosage , Peptide Fragments/metabolism , Reactive Oxygen Species/metabolism
16.
Int J Neurosci ; 127(2): 99-108, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27044501

ABSTRACT

Alzheimer's disease (AD) is the most common form of dementia. Several hypotheses have been put forward to explain the basis of disease onset and progression. A complicated array of molecular events has been implicated in the pathogenesis of AD. It is attributed to a variety of pathological conditions that share similar critical processes, such as oxidative stress, proteinaceous aggregations, mitochondrial dysfunctions and energy failure. There is increasing evidence suggesting that metal homeostasis is dysregulated in the pathology of AD. Biometals play an important role in the normal body functioning but AD may be mediated or triggered by disproportion of metal ions leading to changes in critical biological systems and initiating a cascade of events finally leading to neurodegeneration and cell death. The link is multifactorial, and although the source of the shift in oxidative homeostasis is still unclear, current evidence points to changes in the balance of redox transition metals, especially iron, copper (Cu) and other trace metals. Their levels in the brain are found to be elevated in AD. In other neurodegenerative disorders, Cu, zinc, aluminum and manganese are involved. This paper is a review of recent advances of the role of metals in the pathogenesis and pathophysiology of AD and related neurodegenerative diseases.


Subject(s)
Alzheimer Disease/pathology , Brain/metabolism , Trace Elements/metabolism , Brain/pathology , Brain/physiopathology , Homeostasis/physiology , Humans , Oxidative Stress/physiology
17.
Geriatr Gerontol Int ; 17(8): 1214-1220, 2017 Aug.
Article in English | MEDLINE | ID: mdl-27489036

ABSTRACT

AIM: The present study assessed adherence, barriers, belief and awareness towards the use of medications among multi-ethnic community-dwelling older adults in Malaysia. Medication accessibility, expenditure and perceptions towards medicine labeling among older adults were also evaluated. METHODS: A cross-sectional study was carried out in the central region of Malaysia from January to August 2015. The older adults enrolled in an ongoing prospective community-based geriatric cohort study and prescribed with medicines were interviewed using a 50-item validated questionnaire. RESULTS: Of the 79 older adults interviewed, 39.2% had ≥4 prescribed medications. Most obtained their medications free-of-charge from government hospitals (66, 83.5%). Nearly half (35, 44.3%) had trouble reading labels for medicines that they had received. Chinese older adults (P = 0.001) and those with lower monthly household income (P < 0.001) expressed difficulty in reading medication labels. Most (59, 75.0%) were unable to differentiate between generic and brand names of the medications, and 49.4% of the older adults did not know that all medicines had to be registered with the Ministry of Health, Malaysia. Most older adults had positive beliefs about the necessity of their medications, and 50.6% (n = 40) reported high medication adherence. The medication adherence score was negatively correlated with the concerns score (r = -0.5, P < 0.001). CONCLUSIONS: The findings from the present study provide a unique insight into the diversity of medication use among multiethnic community-dwelling older adults. Although high adherence to medications and positive beliefs about the necessity of medications were reported by the older adults, their knowledge about medications remained insufficient and they had difficulty in reading medication labels. Geriatr Gerontol Int 2017; 17: 1214-1220.


Subject(s)
Attitude to Health/ethnology , Ethnicity , Medication Adherence/ethnology , Polypharmacy , Surveys and Questionnaires , Age Factors , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , Geriatric Assessment , Humans , Independent Living , Malaysia , Male , Risk Assessment , Sex Factors
18.
Geriatr Gerontol Int ; 17(5): 839-846, 2017 May.
Article in English | MEDLINE | ID: mdl-27215446

ABSTRACT

AIM: Cytokines released from chronically-activated microglia could result in neuroinflammation. An accurate profile of the relationship between cytokines and Alzheimer's disease (AD) pathogenesis, as well as the patterns of these inflammatory mediators in AD patients could lead to the identification of peripheral markers for the disease. The present study was undertaken to identify pro- and anti-inflammatory cytokines associated with AD in the Malaysian population. METHODS: Further to informed consent from 39 healthy subjects and 39 probable AD patients, 8.5 mL of peripheral blood was collected and serum was extracted. The differential levels of 12 serum cytokines extracted from peripheral blood samples were measured using Procarta Multiplex Cytokine and enzyme-linked immunoassay kits. Concentrations of cytokines were measured at 615 nm using a fluorometer. RESULTS: Except for tumor necrosis factor-α, all classical pro-inflammatory cytokines (interleukin [IL]-1ß, IL-6, IL-12 and interferon-γ) were found to be significantly upregulated (P < 0.001) in AD patients. Three of the five non-classical pro-inflammatory cytokines (C-X-C motif ligand 10 [CXCL-10], monocyte chemoattractant protein-1 and macrophage inflammatory protein-1α) showed similar patterns. Both classical IL-10 and non-classical IL-13 anti-inflammatory cytokines were significantly downregulated (P < 0.001) in AD patients when compared with non-AD controls. Receiver operating characteristic curve analyses for both CXCL-10 (IP-10) and IL-13 showed a high level of diagnostic accuracy (area under curve = 1 [95% confidence interval]). Both CXCL-10 and IL-13 also showed sensitivity of 100% and specificity of 100% for diagnosis of AD (cut-off values >53.65 ρg/mL and <9.315 ρg/mL, respectively). CONCLUSIONS: Both the non-classical pro-inflammatory CXCL-10 and anti-inflammatory IL-13 cytokines showed promising potential as blood-based cytokine biomarkers for AD. This is the first study of non-classical cytokine profiles of Malaysian AD patients. Geriatr Gerontol Int 2017; 17: 839-846.


Subject(s)
Alzheimer Disease/blood , Cytokines/blood , Interleukin-13/blood , Receptors, CXCR6/blood , Aged , Aged, 80 and over , Alzheimer Disease/diagnosis , Alzheimer Disease/epidemiology , Biomarkers/blood , Enzyme-Linked Immunosorbent Assay , Female , Fluorometry , Humans , Malaysia/epidemiology , Male , Prevalence , Tumor Necrosis Factor-alpha/blood
19.
J Mol Recognit ; 29(11): 544-554, 2016 11.
Article in English | MEDLINE | ID: mdl-27406464

ABSTRACT

The inhibitory role of AgNO3 on glucose-mediated respiration in Escherichia coli has been investigated as a function of pH and temperature using Clark-type electrode, environmental scanning electron microscopy, and computational tools. In the given concentration of bacterial suspension (1 × 108 CFU/ml), E. coli showed an increasing nonlinear trend of tetra-phasic respiration between 1-133 µM glucose concentration within 20 min. The glucose concentrations above 133 µM did not result any linear increment in respiration but rather showed a partial inhibition at higher glucose concentrations (266-1066 µM). In the presence of glucose, AgNO3 caused a concentration-dependent (47-1960 µM) inhibition of the respiration rate within 4 min of its addition. The respiration rate was the highest at pH 7-8 and then was decreased on either side of this pH range. The inhibitory action of AgNO3 upon bacterial respiration was the highest at 37 °C. The observations of the respiration data were well supported by the altered bacterial morphology as observed in electron microscopic study. Docking study indicated the AgNO3 binding to different amino acids of all respiratory complex enzymes in E. coli and thereby explaining its interference with the respiratory chain. Copyright © 2016 John Wiley & Sons, Ltd.


Subject(s)
Electron Transport/drug effects , Escherichia coli/physiology , Glucose/metabolism , Silver Nitrate/pharmacology , Binding Sites , Escherichia coli/drug effects , Escherichia coli/ultrastructure , Escherichia coli Proteins/chemistry , Escherichia coli Proteins/metabolism , Hydrogen-Ion Concentration , Kinetics , Microscopy, Electron, Scanning , Molecular Docking Simulation , Temperature
20.
Pharmacol Biochem Behav ; 146-147: 1-12, 2016.
Article in English | MEDLINE | ID: mdl-27106205

ABSTRACT

Several lines of evidence indicate that beta amyloid (ß-A) production, neurofibrillary tangles and neuroinflammation are interrelated in the pathogenesis of Alzheimer's disease (AD). AD is associated with enhanced ß-A production and accumulation resulting in neuroinflammation probably via activation of lipoxygenase (LOX) and cyclooxygenase (COX) pathways. Therefore, the present study was designed to investigate the role of LOX and COX inhibitors (zafirlukast and valdecoxib) in amyloidogenesis in ß-A1-42 oligomer induced experimental AD in rats. The behavioral activities were assessed using actophotometer, novel object recognition test (ORT), Morris water maze (MWM) followed by biochemical assessments, determination of proinflammatory cytokines and mediators (TNF-α, IL-1ß and PGE2), ß-A1-42 levels and histopathological analysis. ICV administration of ß-A1-42 oligomer produced significant impairment in memory consolidation. In addition to this significant increase in mito-oxidative stress, neuroinflammatory markers, acetylcholinesterase (AChE) toxicity, ß-A1-42 level, neuronal cell death and neuroinflammation are more profound in ß-A1-42 oligomer treated AD rats. Administration of zafirlukast (15 and 30mg/kg), and valdecoxib (5 and 10mg/kg) significantly improved the behavioral performances and showed significant reversal of mito-oxidative damage declining the neuroinflammation in ß-A1-42 oligomer treated rats. Furthermore, more profound effects were observed at the sub-therapeutic dose combination of zafirlukast (15mg/kg) and valdecoxib (5mg/kg). The results of the present study indicate that protective effects of zafirlukast and valdecoxib are achieved through the blockade of release of LOX and COX metabolites therefore, representing a new therapeutic target for treating AD and other neurodegenerative disorders.


Subject(s)
Alzheimer Disease/metabolism , Amyloid beta-Peptides/toxicity , Amyloid/biosynthesis , Lipoxygenase/metabolism , Mitochondria/drug effects , Neuroprotective Agents/pharmacology , Oxidative Stress/drug effects , Peptide Fragments/toxicity , Prostaglandin-Endoperoxide Synthases/metabolism , Alzheimer Disease/chemically induced , Amyloid beta-Peptides/administration & dosage , Amyloid beta-Peptides/metabolism , Animals , Brain/drug effects , Brain/metabolism , Cell Death/drug effects , Disease Models, Animal , Indoles , Injections, Intraventricular , Isoxazoles/pharmacology , Locomotion/drug effects , Male , Memory/drug effects , Mitochondria/metabolism , Peptide Fragments/administration & dosage , Peptide Fragments/metabolism , Phenylcarbamates , Rats , Recognition, Psychology/drug effects , Signal Transduction/drug effects , Sulfonamides/pharmacology , Tosyl Compounds/pharmacology
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