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Fulltext Lipids as key biomarkers in unravelling the pathophysiology of obesity-related metabolic dysregulation

Osman AA, Chin SF, Teh LK, Abdullah N, Abdul Murad NA, Jamal R

Heliyon, 2025 Feb 15;11(3):e42197.
PMID: 39995923 DOI: 10.1016/j.heliyon.2025.e42197

BACKGROUND AND OBJECTIVE: Obesity is intricately linked with metabolic disturbances. The comprehensive exploration of metabolomes is important in unravelling the complexities of obesity development. This study was aimed to discern unique metabolite signatures in obese and lean individuals using liquid chromatography-mass spectrometry quadruple time-of-flight (LC-MS/Q-TOF), with the goal of elucidating their roles in obesity.
METHODS: A total of 160 serum samples (Discovery, n = 60 and Validation, n = 100) of obese and lean individuals with stable Body Mass Index (BMI) values were retrieved from The Malaysian Cohort biobank. Metabolic profiles were obtained using LC-MS/Q-TOF in dual-polarity mode. Metabolites were identified using a molecular feature and chemical formula algorithm, followed by a differential analysis using MetaboAnalyst 5.0. Validation of potential metabolites was conducted by assessing their presence through collision-induced dissociation (CID) using a targeted tandem MS approach.
RESULTS: A total of 85 significantly differentially expressed metabolites (p-value <0.05; -1.5 < FC > 1.5) were identified between the lean and the obese individuals, with the lipid class being the most prominent. A stepwise logistic regression revealed three metabolites associated with increased risk of obesity (14-methylheptadecanoic acid, 4'-apo-beta,psi-caroten-4'al and 6E,9E-octadecadienoic acid), and three with lower risk of obesity (19:0(11Me), 7,8-Dihydro-3b,6a-dihydroxy-alpha-ionol 9-[apiosyl-(1->6)-glucoside] and 4Z-Decenyl acetate). The model exhibited outstanding performance with an AUC value of 0.95. The predictive model underwent evaluation across four machine learning algorithms consistently demonstrated the highest predictive accuracy of 0.821, aligning with the findings from the classical logistic regression statistical model. Notably, the presence of 4'-apo-beta,psi-caroten-4'-al showed a statistically significant difference between the lean and obese individuals among the metabolites included in the model.
CONCLUSIONS: Our findings highlight the significance of lipids in obesity-related metabolic alterations, providing insights into the pathophysiological mechanisms contributing to obesity. This underscores their potential as biomarkers for metabolic dysregulation associated with obesity.
Exploring the transcription start sites and other genomic features facilitates the accurate identification and annotation of small RNAs across multiple stress conditions in Mycobacterium tuberculosis

Cheah HL, Citartan M, Lee LP, Ahmed SA, Salleh MZ, Teh LK, et al.

Funct Integr Genomics, 2024 Sep 12;24(5):160.
PMID: 39264475 DOI: 10.1007/s10142-024-01437-5

Mycobacterium tuberculosis (MTB) is a pathogen that is known for its ability to persist in harsh environments and cause chronic infections. Understanding the regulatory networks of MTB is crucial for developing effective treatments. Small regulatory RNAs (sRNAs) play important roles in gene expression regulation in all kingdoms of life, and their classification based solely on genomic location can be imprecise due to the computational-based prediction of protein-coding genes in bacteria, which often neglects segments of mRNA such as 5'UTRs, 3'UTRs, and intercistronic regions of operons. To address this issue, our study simultaneously discovered genomic features such as TSSs, UTRs, and operons together with sRNAs in the M. tuberculosis H37Rv strain (ATCC 27294) across multiple stress conditions. Our analysis identified 1,376 sRNA candidates and 8,173 TSSs in MTB, providing valuable insights into its complex regulatory landscape. TSS mapping enabled us to classify these sRNAs into more specific categories, including promoter-associated sRNAs, 5'UTR-derived sRNAs, 3'UTR-derived sRNAs, true intergenic sRNAs, and antisense sRNAs. Three of these sRNA candidates were experimentally validated using 3'-RACE-PCR: predictedRNA_0240, predictedRNA_0325, and predictedRNA_0578. Future characterization and validation are necessary to fully elucidate the functions and roles of these sRNAs in MTB. Our study is the first to simultaneously unravel TSSs and sRNAs in MTB and demonstrate that the identification of other genomic features, such as TSSs, UTRs, and operons, allows for more accurate and specific classification of sRNAs.
Fulltext Antinociceptive Activity of Petroleum Ether Fraction of Clinacanthus nutans Leaves Methanolic Extract: Roles of Nonopioid Pain Modulatory Systems and Potassium Channels

Zakaria ZA, Abdul Rahim MH, Roosli RAJ, Mohd Sani MH, Marmaya NH, Omar MH, et al.

Biomed Res Int, 2019;2019:6593125.
PMID: 31467905 DOI: 10.1155/2019/6593125

Methanolic extract of Clinacanthus nutans Lindau leaves (MECN) has been reported to exert antinociceptive activity. The present study aimed to elucidate the possible antinociceptive mechanisms of a lipid-soluble fraction of MECN, which was obtained after sequential extraction in petroleum ether. The petroleum ether fraction of C. nutans (PECN), administered orally to mice, was (i) subjected to capsaicin-, glutamate-, phorbol 12-myristate 13-acetate-, bradykinin-induced nociception model; (ii) prechallenged (intraperitoneal (i.p.)) with 0.15 mg/kg yohimbine, 1 mg/kg pindolol, 3 mg/kg caffeine, 0.2 mg/kg haloperidol, or 10 mg/kg atropine, which were the respective antagonist of α 2-adrenergic, β-adrenergic, adenosinergic, dopaminergic, or muscarinic receptors; and (iii) prechallenged (i.p.) with 10 mg/kg glibenclamide, 0.04 mg/kg apamin, 0.02 mg/kg charybdotoxin, or 4 mg/kg tetraethylammonium chloride, which were the respective inhibitor of ATP sensitive-, small conductance Ca2+-activated-, large conductance Ca2+-activated-, or nonselective voltage-activated-K+ channel. Results obtained demonstrated that PECN (100, 250, and 500 mg/kg) significantly (P<0.05) inhibited all models of nociception described earlier. The antinociceptive activity of 500 mg/kg PECN was significantly (P<0.05) attenuated when prechallenged with all antagonists or K+ channel blockers. However, only pretreatment with apamin and charybdotoxin caused full inhibition of PECN-induced antinociception. The rest of the K+ channel blockers and all antagonists caused only partial inhibition of PECN antinociception, respectively. Analyses on PECN's phytoconstituents revealed the presence of antinociceptive-bearing bioactive compounds of volatile (i.e., derivatives of γ-tocopherol, α-tocopherol, and lupeol) and nonvolatile (i.e., cinnamic acid) nature. In conclusion, PECN exerts a non-opioid-mediated antinociceptive activity involving mainly activation of adenosinergic and cholinergic receptors or small- and large-conductance Ca2+-activated-K+ channels.
Association of ABCC2 with levels and toxicity of methotrexate in Malaysian Childhood Acute Lymphoblastic Leukemia (ALL)

Razali RH, Noorizhab MNF, Jamari H, James RJ, Teh KH, Ibrahim HM, et al.

Pediatr Hematol Oncol, 2020 Apr;37(3):185-197.
PMID: 31870219 DOI: 10.1080/08880018.2019.1705949

Studies had shown that genetic polymorphism plays a significant role in the pharmacokinetics and pharmacodynamics variation of high dose methotrexate (MTX), 5000 mg/m2 regimen. The objective of this study was to investigate the genetic variations associated with the serum level and toxicity of MTX in Malaysian children with acute lymphoblastic leukemia (ALL). Thirty-eight patients were genotyped for rs717620 (ABCC2), rs4948496 (ARID5B), rs1801133 (MTHFR) and rs4149056 (SLCO1B1). Serum levels of MTX at 48 h post 24 h of intravenous infusion were analyzed by high-performance liquid chromatography-mass spectrometry. The ABCC2 genotype was significantly associated with the serum levels of MTX at 48 h after treatment (p = 0.017). Patients with CT and TT of rs717620 (ABCC2) and TC and CC of rs4948496 (ARID5B) were significantly associated with leukopenia grade I-IV (Fisher Exact Test; p = 0.03 and 0.02, respectively). The three most common MTX related toxicities were leukopenia (60.5%), increased alanine aminotransferase enzyme (47.4%), and thrombocytopenia (47.4%). Our results demonstrate that by prescreening of patients for ABCC2 and ARID5B associated with the serum levels and adverse effects of MTX would identify patients at risk and therefore help a pediatric oncologist to personalize chemotherapy drugs for precision health.
Fulltext Mitochondrial DNA mutations in Malaysian female breast cancer patients

Omasanggar R, Yu CY, Ang GY, Emran NA, Kitan N, Baghawi A, et al.

PLoS One, 2020;15(5):e0233461.
PMID: 32442190 DOI: 10.1371/journal.pone.0233461

Cancer development has been ascribed with diverse genetic variations which are identified in both mitochondrial and nuclear genomes. Mitochondrial DNA (mtDNA) alterations have been detected in several tumours which include lung, colorectal, renal, pancreatic and breast cancer. Several studies have explored the breast tumour-specific mtDNA alteration mainly in Western population. This study aims to identify mtDNA alterations of 20 breast cancer patients in Malaysia by next generation sequencing analysis. Twenty matched tumours with corresponding normal breast tissues were obtained from female breast cancer patients who underwent mastectomy. Total DNA was extracted from all samples and the entire mtDNA (16.6kb) was amplified using long range PCR amplification. The amplified PCR products were sequenced using mtDNA next-generation sequencing (NGS) on an Illumina Miseq platform. Sequencing involves the entire mtDNA (16.6kb) from all pairs of samples with high-coverage (~ 9,544 reads per base). MtDNA variants were called and annotated using mtDNA-Server, a web server. A total of 18 of 20 patients had at least one somatic mtDNA mutation in their tumour samples. Overall, 65 somatic mutations were identified, with 30 novel mutations. The majority (59%) of the somatic mutations were in the coding region, whereas only 11% of the mutations occurred in the D-loop. Notably, somatic mutations in protein-coding regions were non-synonymous (49%) in which 15.4% of them are potentially deleterious. A total of 753 germline mutations were identified and four of which were novel mutations. Compared to somatic alterations, less than 1% of germline missense mutations are harmful. The findings of this study may enhance the current knowledge of mtDNA alterations in breast cancer. To date, the catalogue of mutations identified in this study is the first evidence of mtDNA alterations in Malaysian female breast cancer patients.
Fulltext Hepatoprotective action of various partitions of methanol extract of Bauhinia purpurea leaves against paracetamol-induced liver toxicity: involvement of the antioxidant mechanisms

Zakaria ZA, Yahya F, Mamat SS, Mahmood ND, Mohtarrudin N, Taher M, et al.

BMC Complement Altern Med, 2016;16(1):175.
PMID: 27287196 DOI: 10.1186/s12906-016-1110-4

Methanol extract of Bauhinia purpurea L. (family Fabaceae) (MEBP) possesses high antioxidant and anti-inflammatory activities and recently reported to exert hepatoprotection against paracetamol (PCM)-induced liver injury in rats. In an attempt to identify the hepatoprotective bioactive compounds in MEBP, the extract was prepared in different partitions and subjected to the PCM-induced liver injury model in rats.
Identification of novel acetylcholinesterase inhibitors: Indolopyrazoline derivatives and molecular docking studies

Chigurupati S, Selvaraj M, Mani V, Selvarajan KK, Mohammad JI, Kaveti B, et al.

Bioorg Chem, 2016 08;67:9-17.
PMID: 27231830 DOI: 10.1016/j.bioorg.2016.05.002

The synthesis of novel indolopyrazoline derivatives (P1-P4 and Q1-Q4) has been characterized and evaluated as potential anti-Alzheimer agents through in vitro Acetylcholinesterase (AChE) inhibition and radical scavenging activity (antioxidant) studies. Specifically, Q3 shows AChE inhibition (IC50: 0.68±0.13μM) with strong DPPH and ABTS radical scavenging activity (IC50: 13.77±0.25μM and IC50: 12.59±0.21μM), respectively. While P3 exhibited as the second most potent compound with AChE inhibition (IC50: 0.74±0.09μM) and with DPPH and ABTS radical scavenging activity (IC50: 13.52±0.62μM and IC50: 13.13±0.85μM), respectively. Finally, molecular docking studies provided prospective evidence to identify key interactions between the active inhibitors and the AChE that furthermore led us to the identification of plausible binding mode of novel indolopyrazoline derivatives. Additionally, in-silico ADME prediction using QikProp shows that these derivatives fulfilled all the properties of CNS acting drugs. This study confirms the first time reporting of indolopyrazoline derivatives as potential anti-Alzheimer agents.
Fulltext Coupling Genotyping and Computational Modeling in Prediction of Anti-epileptic Drugs that cause Stevens Johnson Syndrome and Toxic Epidermal Necrolysis for Carrier of HLA-B*15:02

Teh LK, Selvaraj M, Bannur Z, Ismail MI, Rafia H, Law WC, et al.

J Pharm Pharm Sci, 2016;19(1):147-60.
PMID: 27096699 DOI: 10.18433/J38G7X

PURPOSE: The importance of HLA-B*15:02 genotyping to avoid carbamazepine induced SJS/TEN and molecular modeling to predict the role of HLA-B*15:0 and AEDs induced SJS/TEN are investigated.
METHODS: DNA was extracted from eighty-six patients. The patients were genotyped by AS-PCR. Computational modeling of the HLA-B*15:02 followed by docking studies were performed to screen 26 AEDs that may induce ADR among HLA-B*15:02 carriers.
RESULTS: Odd ratio for CBZ induced SJS/TEN and HLA-B*15:02 was 609.0 (95% CI: 23-15873; p=0.0002). Molecular modeling studies showed that acetazolamide, ethosuxiamide, lamotrigine, oxcarbazepine, phenobarbital, phenytoin, primidone and sodium-valproate may induce ADR in HLA-B*15:02 carriers alike CBZ. Conclusion. We confirmed HLA-B*15:02 as a predictor of SJS/TEN and recommend pre-screening. Computational prediction of DIHR is useful in personalized medicine.
Fulltext Adolescent kratom exposure affects cognitive behaviours and brain metabolite profiles in Sprague-Dawley rats

Zul Aznal AN, Mohamad Nor Hazalin NA, Hassan Z, Mat NH, Chear NJ, Teh LK, et al.

Front Pharmacol, 2022;13:1057423.
PMID: 36518677 DOI: 10.3389/fphar.2022.1057423

Adolescence is a critical developmental period during which exposure to psychoactive substances like kratom (Mitragyna speciosa) can cause long-lasting deleterious effects. Here, we evaluated the effects of mitragynine, the main alkaloid of kratom, and lyophilised kratom decoction (LKD) on cognitive behaviours and brain metabolite profiles in adolescent rats. Male Sprague-Dawley rats (Postnatal day, PND31) were given vehicle, morphine (5 mg/kg), mitragynine (3, 10, or 30 mg/kg), or LKD (equivalent dose of 30 mg/kg mitragynine) for 15 consecutive days. Later, a battery of behavioural testing was conducted, brain was extracted and metabolomic analysis was performed using LCMS-QTOF. The results showed that mitragynine did not affect the recognition memory in the novel object recognition task. In the social interaction task, morphine, mitragynine, and LKD caused a marked deficit in social behaviour, while in Morris water maze task, mitragynine and LKD only affected reference memory. Metabolomic analysis revealed distinct metabolite profiles of animals with different treatments. Several pathways that may be involved in the effects of kratom exposure include arachidonic acid, pantothenate and CoA, and tryptophan pathways, with several potential biomarkers identified. These findings suggest that adolescent kratom exposure can cause cognitive behavioural deficits that may be associated with changes in the brain metabolite profiles.
Fulltext Exposure of Helicobacter pylori to clarithromycin in vitro resulting in the development of resistance and triggers metabolic reprogramming associated with virulence and pathogenicity

Rosli NA, Al-Maleki AR, Loke MF, Tay ST, Rofiee MS, Teh LK, et al.

PLoS One, 2024;19(3):e0298434.
PMID: 38446753 DOI: 10.1371/journal.pone.0298434

In H. pylori infection, antibiotic-resistance is one of the most common causes of treatment failure. Bacterial metabolic activities, such as energy production, bacterial growth, cell wall construction, and cell-cell communication, all play important roles in antimicrobial resistance mechanisms. Identification of microbial metabolites may result in the discovery of novel antimicrobial therapeutic targets and treatments. The purpose of this work is to assess H. pylori metabolomic reprogramming in order to reveal the underlying mechanisms associated with the development of clarithromycin resistance. Previously, four H. pylori isolates were induced to become resistant to clarithromycin in vitro by incrementally increasing the concentrations of clarithromycin. Bacterial metabolites were extracted using the Bligh and Dyer technique and analyzed using metabolomic fingerprinting based on Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry (LC-Q-ToF-MS). The data was processed and analyzed using the MassHunter Qualitative Analysis and Mass Profiler Professional software. In parental sensitivity (S), breakpoint isolates (B), and induced resistance isolates (R) H. pylori isolates, 982 metabolites were found. Furthermore, based on accurate mass, isotope ratios, abundances, and spacing, 292 metabolites matched the metabolites in the Agilent METLIN precise Mass-Personal Metabolite Database and Library (AM-PCDL). Several metabolites associated with bacterial virulence, pathogenicity, survival, and proliferation (L-leucine, Pyridoxone [Vitamine B6], D-Mannitol, Sphingolipids, Indoleacrylic acid, Dulcitol, and D-Proline) were found to be elevated in generated resistant H. pylori isolates when compared to parental sensitive isolates. The elevated metabolites could be part of antibiotics resistance mechanisms. Understanding the fundamental metabolome changes in the course of progressing from clarithromycin-sensitive to breakpoint to resistant in H. pylori clinical isolates may be a promising strategy for discovering novel alternatives therapeutic targets.
A study on the genetic polymorphisms of CYP3A5 among the Orang Asli in Malaysia using a next generation sequencing platform

Ang GY, Yu CY, Johari James R, Ahmad A, Abdul Rahman T, Mohd Nor F, et al.

Ann Hum Biol, 2018 Mar;45(2):166-169.
PMID: 29447003 DOI: 10.1080/03014460.2018.1440004

BACKGROUND: CYP3A5 is the predominant sub-family of biotransformation enzymes in the liver and the genetic variations in CYP3A5 are an important determinant of inter-individual and inter-ethnic differences in CYP3A-mediated drug disposition and response.
AIM: This study aims to investigate the genetic polymorphisms of CYP3A5 among the Orang Asli in Peninsular Malaysia using a next generation sequencing platform.
METHODS: Genomic DNAs were extracted from blood samples of the three main Orang Asli tribes and whole-genome sequencing was performed.
RESULTS: A total of 61 single nucleotide polymorphisms were identified and all the SNPs were located in introns except rs15524, which is in the 3'UTR, and 11 of these polymorphisms were novel. Two allelic variants and three genotypes were identified in the Orang Asli. The major allelic variant was the non-functional CYP3A5*3 (66.4%). The percentages of Orang Asli with CYP3A5*3/*3 (47.2%) and CYP3A5*1/*3 (38.1%) genotypes are more than twice the percentage of Orang Asli with CYP3A5*1/*1 (14.8%) genotype. Almost half of the Orang Asli harboured CYP3A5 non-expressor genotype (CYP3A5*3/*3).
CONCLUSIONS: The predominance of the CYP3A5 non-expressor genotype among the Orang Asli was unravelled and the findings in this study may serve as a guide for the optimisation of pharmacotherapy for the Orang Asli community.
Genotype-Phenotype Correlation of β-Thalassemia in Malaysian Population: Toward Effective Genetic Counseling

Abdullah UYH, Ibrahim HM, Mahmud NB, Salleh MZ, Teh LK, Noorizhab MNFB, et al.

Hemoglobin, 2020 May;44(3):184-189.
PMID: 32586164 DOI: 10.1080/03630269.2020.1781652

Effective prevention of β-thalassemia (β-thal) requires strategies to detect at-risk couples. This is the first study attempting to assess the prevalence of silent β-thal carriers in the Malaysian population. Hematological and clinical parameters were evaluated in healthy blood donors and patients with β-thal trait, Hb E (HBB: c.79G>A)/β-thal and β-thal major (β-TM). β-Globin gene sequencing was carried out for 52 healthy blood donors, 48 patients with Hb E/β-thal, 34 patients with β-TM and 38 patients with β-thal trait. The prevalence of silent β-thal carrier phenotypes found in 25.0% of healthy Malaysian blood donors indicates the need for clinician's awareness of this type in evaluating β-thal in Malaysia. Patients with β-TM present at a significantly younger age at initial diagnosis and require more blood transfusions compared to those with Hb E/β-thal. The time at which genomic DNA was extracted after blood collection, particularly from patients with β-TM and Hb E/β-thal, was found to be an important determinant of the quality of the results of the β-globin sequencing. Public education and communication campaigns are recommended as apparently healthy individuals have few or no symptoms and normal or borderline hematological parameters. β-Globin gene mutation characterization and screening for silent β-thal carriers in regions prevalent with β-thal are recommended to develop more effective genetic counseling and management of β-thal.
Determination toxic effects of Hystrix Brachyura Bezoar extracts using cancer cell lines and embryo zebrafish (Danio rerio) models and identification of active principles through GC-MS analysis

Firus Khan AY, Ahmed QU, Nippun TS, Hilles A, Jalal TK, Teh LK, et al.

J Ethnopharmacol, 2020 Nov 15;262:113138.
PMID: 32726681 DOI: 10.1016/j.jep.2020.113138

ETHNOPHARMACOLOGICAL RELEVANCE: Porcupine bezoar (PB) is used as folk medicine for various medical conditions including cancer treatment in Malaysia. However, its toxicity profile has never been thoroughly ascertained to confirm its safe nature as an efficacious traditional medicine in the treatment of cancer as well as other ailments.
AIM OF THE STUDY: This study was aimed to reveal three different PBs' aqueous extracts(viz. PB-A, PB-B, PB-C) chemical constituent's profile using GC-MS analysis, anticancer property on A375, HeLa and MCF7 cancer cells, toxicity profile on zebrafish embryo morphology, EC50, LC50 and teratogenicity index.
MATERIALS AND METHODS: PBs' extracts characterization was performed through GC-MS analysis, in vitro anticancer effect was carried out on A375, HeLa and MCF7 cancer cell lines and finally and toxicity properties on three different PBs aqueous extracts (viz. PB-A, PB-B, PB-C) were determined using zebrafish embryo model.
RESULTS: The GC-MS analysis revealed 10 similar compounds in all PBs' extracts. Dilauryl thiodipropionate was found to be a major compound in all PBs' extracts followed by tetradecanoic acid. An in vitro anticancer study revealed PB extracts exerted median inhibition concentration (IC50) <50 μg/mL, on cancer cells viz. A375, HeLa and MCF7 with no significant toxicity on normal cells viz. NHDF cells. In vivo toxicity of PBs extracts found affecting tail detachment, hatching, craniofacial, brain morphology, soft tissues, edema, spinal, somites, notochord and cardiovascular system (brachycardia, disruption of blood circulation) deformities. The LC50 and EC50 demonstrated PB extracts effect as dose and time dependent with median concentration <150.0 μg/mL. Additionally, teratogenicity index (TI) viz. >1.0 revealed teratogenic property for PB extracts.
CONCLUSIONS: The findings revealed that all three PBs aqueous extracts possessed anticancer activity and exhibited significant toxicological effects on zebrafish embryos with high teratogenicity index. Hence, its use as an anticancer agent requires further investigation and medical attentions to determine its safe dose.
Metabolomic-guided discovery of Alzheimer's disease biomarkers from body fluid

Enche Ady CNA, Lim SM, Teh LK, Salleh MZ, Chin AV, Tan MP, et al.

J Neurosci Res, 2017 Oct;95(10):2005-2024.
PMID: 28301062 DOI: 10.1002/jnr.24048

The rapid increase in the older population has made age-related diseases like Alzheimer's disease (AD) a global concern. Given that there is still no cure for this neurodegenerative disease, the drastic growth in the number of susceptible individuals represents a major emerging threat to public health. The poor understanding of the mechanisms underlying AD is deemed the greatest stumbling block against progress in definitive diagnosis and management of this disease. There is a dire need for biomarkers that can facilitate early diagnosis, classification, prognosis, and treatment response. Efforts have been directed toward discovery of reliable and distinctive AD biomarkers but with very little success. With the recent emergence of high-throughput technology that is able to collect and catalogue vast datasets of small metabolites, metabolomics offers hope for a better understanding of AD and subsequent identification of biomarkers. This review article highlights the potential of using multiple metabolomics platforms as useful means in uncovering AD biomarkers from body fluids. © 2017 Wiley Periodicals, Inc.
Fulltext Semipurified Ethyl Acetate Partition of Methanolic Extract of Melastoma malabathricum Leaves Exerts Gastroprotective Activity Partly via Its Antioxidant-Antisecretory-Anti-Inflammatory Action and Synergistic Action of Several Flavonoid-Based Compounds

Ismail Suhaimy NW, Noor Azmi AK, Mohtarrudin N, Omar MH, Tohid SF, Cheema MS, et al.

Oxid Med Cell Longev, 2017;2017:6542631.
PMID: 28168011 DOI: 10.1155/2017/6542631

Recent study has demonstrated the gastroprotective activity of crude methanolic extract of M. malabathricum leaves. The present study evaluated the gastroprotective potential of semipurified extracts (partitions): petroleum ether, ethyl acetate (EAMM), and aqueous obtained from the methanolic extract followed by the elucidation of the gastroprotective mechanisms of the most effective partition. Using the ethanol-induced gastric ulcer assay, all partitions exerted significant gastroprotection, with EAMM being the most effective partition. EAMM significantly (i) reduced the volume and acidity (free and total) while increasing the pH of gastric juice and enhanced the gastric wall mucus secretion when assessed using the pylorus ligation assay, (ii) increased the enzymatic and nonenzymatic antioxidant activity of the stomach tissue, (iii) lost its gastroprotective activity following pretreatment with N-omega-nitro-L-arginine methyl ester (L-NAME; NO blocker) or carbenoxolone (CBXN; NP-SH blocker), (iv) exerted antioxidant activity against various in vitro oxidation assays, and (v) showed moderate in vitro anti-inflammatory activity via the LOX-modulated pathway. In conclusion, EAMM exerts a remarkable NO/NP-SH-dependent gastroprotective effect that is attributed to its antisecretory and antioxidant activities, ability to stimulate the gastric mucus production and endogenous antioxidant system, and synergistic action of several gastroprotective-induced flavonoids.
Inference of the Genetic Polymorphisms of CYP2D6 in Six Subtribes of the Malaysian Orang Asli from Whole-Genome Sequencing Data

Yu CY, Ang GY, Subramaniam V, Johari James R, Ahmad A, Abdul Rahman T, et al.

Genet Test Mol Biomarkers, 2017 Jul;21(7):409-415.
PMID: 28525288 DOI: 10.1089/gtmb.2016.0235

AIMS: CYP2D6 is one of the major enzymes in the cytochrome P450 monooxygenase system. It metabolizes ∼25% of prescribed drugs and hence, the genetic diversity of a CYP2D6 gene has continued to be of great interest to the medical and pharmaceutical industries. This study was designed to perform a systematic analysis of the CYP2D6 gene in six subtribes of the Malaysian Orang Asli.
METHODS: Genomic DNAs were extracted from the blood samples followed by whole-genome sequencing. The reads were aligned to the reference human genome hg19 and variants in the CYP2D6 gene were analyzed. CYP2D6*5 and duplication of CYP2D6 were analyzed using previously established methods.
RESULTS: A total of 72 single nucleotide polymorphisms were identified. CYP2D6*1, *2, *4, *5, *10,*41, and duplication of the gene were found in the Orang Asli, whereby CYP2D6*2 and *41 alleles are reported for the first time in the Malaysian population.
CONCLUSION: The findings in this study provide insights into the genetic polymorphisms of CYP2D6 in the Orang Asli of Peninsular Malaysia.
Discovery of polymethoxyflavones as potential cyclooxygenase-2 (COX-2), 5-lipoxygenase (5-LOX) and phosphodiesterase 4B (PDE4B) inhibitors

Md Idris MH, Mohd Amin SN, Mohd Amin SN, Wibowo A, Zakaria ZA, Shaameri Z, et al.

J Recept Signal Transduct Res, 2021 Jul 29.
PMID: 34323638 DOI: 10.1080/10799893.2021.1951756

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely prescribed to treat inflammatory-related diseases, pain and fever. However, the prolong use of traditional NSAIDs leads to undesirable side effects such as gastric, ulceration, and renal toxicity due to lack of selectivity toward respective targets for COX-2, 5-LOX, and PDE4B. Thus, targeting multiple sites can reduce these adverse effects of the drugs and increase its potency. A series of methoxyflavones (F1-F5) were synthesized and investigated for their anti-inflammatory properties through molecular docking and inhibition assays. Among these flavones, only F2 exhibited selectivity toward COX-2 (Selectivity Index, SI: 3.90, COX-2 inhibition: 98.96 ± 1.47%) in comparison with celecoxib (SI: 7.54, COX-2 inhibition: 98.20 ± 2.55%). For PDEs, F3 possessed better selectivity to PDE4B (SI: 4.67) than rolipram (SI: 0.78). F5 had the best 5-LOX inhibitory activity among the flavones (33.65 ± 4.74%) but less than zileuton (90.81 ± 0.19%). Docking analysis indicated that the position of methoxy group and the substitution of halogen play role in determining the bioactivities of flavones. Interestingly, F1-F5 displayed favorable pharmacokinetic profiles and acceptable range of toxicity (IC50>70 µM) in cell lines with the exception for F1 (IC50: 16.02 ± 1.165 µM). This study generated valuable insight in designing new anti-inflammatory drug based on flavone scaffold. The newly synthesized flavones can be further developed as future therapeutic agents against inflammation.
Fulltext Stress, Anxiety and Depression among a Cohort of Health Sciences Undergraduate Students: The Prevalence and Risk Factors

Fauzi MF, Anuar TS, Teh LK, Lim WF, James RJ, Ahmad R, et al.

Int J Environ Res Public Health, 2021 03 22;18(6).
PMID: 33809939 DOI: 10.3390/ijerph18063269

Stress, anxiety, and depression (SAD) have a negative impact on the learning and academic performance of university students. Hence, this study aimed to determine the prevalence, as well as the risk factors associated with SAD among a cohort of students pursuing undergraduate degree courses in health sciences. This is part of the strategy in building a healthy nation. A questionnaire containing socio-demographic factors and the short version of Depression, Anxiety, and Stress Scale-21 (DASS-21) was used to assess the likelihood of psychological distress. Logistic regression analysis was conducted to determine the risk factors of SAD. In total, 449 students completed the questionnaire (93.9% response rate). Of these, 65% had stress, 85.1% had anxiety and 51.4% had depression. Most cases of stress (74.6%) and depression (66.2%) were of normal-to-mild level, while 74.6% of them showed moderate-to-extremely severe anxiety. There was a statistically significant association between stress score and the year of study. In the regression analysis, poor sleep quality and fatigue were risk factors of anxiety and depression, whereas low-grade fever and frequent headaches were risk factors for stress and anxiety. Stress, anxiety, and depression scores were significantly higher among students studying medical imaging. A substantial proportion of health science students are suffering from SAD. This study recommends screening and close monitoring of the above-mentioned predictors and the formulation of comprehensive intervention strategies for students with SAD.
Fulltext Draft Genome Sequences of Local Clinical Isolates of Drug-Resistant and Drug-Sensitive Mycobacterium tuberculosis

Zainal Abidin N, Noorizhab MNF, Teh LK, Lim WF, Mohd Noordin N, Aziz ZA, et al.

Microbiol Resour Announc, 2021 Jun 24;10(25):e0035221.
PMID: 34165334 DOI: 10.1128/MRA.00352-21

In the battle against tuberculosis (TB), plasticity of the Mycobacterium tuberculosis genome is believed to contribute to the pathogen's virulence and drug resistance. Here, we report 10 draft genome sequences of clinical M. tuberculosis isolated in Malaysia as the basis for understanding the genome plasticity of the M. tuberculosis isolates.
Porous NiTi Dental Implant Fabricated by a Metal Injection Molding: An in Vivo Biocompatibility Evaluation in an Animal Model

Mustafa NWNA, Ahmad R, Ahmad Khushaini MA, Kamar Affendi NH, Ab Ghani SM, Tan SK, et al.

ACS Biomater Sci Eng, 2024 Jan 08;10(1):405-419.
PMID: 38040671 DOI: 10.1021/acsbiomaterials.3c01551

This study assessed the corrosion resistance, intracutaneous reactivity, acute systemic toxicity, and in situ tissue effect of the implantation of porous NiTi fabricated by metal injection molding in animal models. For the intracutaneous reactivity study, five intracutaneous injections were administered per site with and without the tested extract in polar and nonpolar solutions. The extract was also delivered via intravenous and intraperitoneal routes for acute systemic toxicity. TiAl6 V4 (control) and porous NiTi were implanted in rabbit femora for a period of 13 weeks to evaluate the in situ tissue response. Corrosion was evaluated through open and cyclic polarization in PBS, while biocompatibility was investigated by assessing the general conditions, skin irritation score (edema and erythema), and histopathology. No active dissolution or hysteresis loop was observed in the corrosion study. None of the animals exhibited death, moribundity, impending death, severe pain, self-mutilation, or overgrooming. No edema was observed at injection sites. Only the positive control showed an erythematous reaction at 24, 48, and 72 h observations (p < 0.001). Porous NiTi showed a low in situ biological response for inflammation, neovascularization, and fibrosis in comparison to the control implant (p = 0.247, 0.005, and 0.011, respectively). Porous NiTi also demonstrated high pitting corrosion resistance while causing no acute hypersensitivity or acute systemic toxicity. The study concludes that porous NiTi implants were unlikely to cause local sensitization, acute systemic toxicity, or chronic inflammatory reactions in an animal model. Porous NiTi also exhibited osseointegration equivalent to Ti6AI4 V of known biocompatibility.

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