MyMedR

Displaying publications 81 - 100 of 129 in total

Abstract:

Sort:

Fulltext A re-evaluation of plasma sialic acid determination using the periodate resorcinol method versus the enzymatic method

Muniandy S, Qvist R, Zaini A, Chinna K, Ismail IS

Southeast Asian J. Trop. Med. Public Health, 2005 Jul;36(4):1011-3.
PMID: 16295560

The concentration of plasma sialic acid was estimated using the modified chemical method and the more sensitive enzymatic method in 20 subjects with impaired glucose tolerance and 20 control subjects. The mean sialic acid concentration values of the control subjects and subjects with impaired glucose tolerance using the enzymatic method were 1.747 +/- 0.047 and 2.583 +/- 0.070 mmole/l and 1.753 +/- 0.067 and 2.591 +/- 1.02 mmole/l for the chemical method. The intra-assay coefficient of variation for the control subjects and for the subjects with impaired glucose tolerance were 1.963% and 1.583%, respectively, for the enzymatic assay and 2.728% and 2.431%, respectively, for the chemical assay. The inter-assay coefficient of variation for the control subjects and for the subjects with impaired glucose tolerance were 2.686% and 2.723% for the enzymatic assay, and 3.819% and 3.95% for the chemical assay. Since the values do not differ significantly, the chemical assay is a cost effective method that can be used in large epidemiological studies.
Fulltext Molecular Docking Analysis of Selected Clinacanthus nutans Constituents as Xanthine Oxidase, Nitric Oxide Synthase, Human Neutrophil Elastase, Matrix Metalloproteinase 2, Matrix Metalloproteinase 9 and Squalene Synthase Inhibitors

Narayanaswamy R, Isha A, Wai LK, Ismail IS

Pharmacogn Mag, 2016 Jan;12(Suppl 1):S21-6.
PMID: 27041853 DOI: 10.4103/0973-1296.176111

Clinacanthus nutans (Burm. f.) Lindau has gained popularity among Malaysians as a traditional plant for anti-inflammatory activity.
Anti-inflammatory evaluation of Scurrula ferruginea (jack) danser parasitizing on Tecoma stans (L.) H.B.K. in LPS/IFN-γ-induced RAW 264.7 macrophages

Hong X, Ajat M, Fakurazi S, Noor AM, Ismail IS

J Ethnopharmacol, 2021 Mar 25;268:113647.
PMID: 33271242 DOI: 10.1016/j.jep.2020.113647

ETHNOPHARMACOLOGICAL RELEVANCE: Scurrula ferruginea (Jack) Danser (locally known as 'Dedalu' or 'dian nan ji sheng' in Malaysia and China) is a hemi-parasitic shrub that is widely used as herbal medicine to treat inflammation, rheumatism, and stroke. However, the scientific basis of its anti-inflammatory function and mechanism remain to be proven.
AIM OF THE STUDY: To evaluate the anti-inflammatory activity as well as the preliminary mechanism of S. ferruginea parasitizing on Tecoma stans.
MATERIALS AND METHODS: The anti-inflammatory capability of freeze-dried stem aqueous extract was assessed via inhibition of inflammatory cytokines interleukin- (IL-) 1β, IL-6, IL-10, and tumor necrosis factor-alpha (TNF-α) production in lipopolysaccharide (LPS) and interferon-γ (IFN-γ) stimulated RAW 264.7 macrophages. The underlying anti-inflammatory mechanism was deciphered through reverse transcriptase and real time quantitative polymerase chain reactions (RT-PCR and qPCR) for inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), IL-1β, and TNF-α mRNA expression.
RESULTS: The results exhibited that aqueous extract of freeze-dried S. ferruginea stem sample concentration-dependently inhibited IL-1β protein production along with the down regulation of iNOS and IL-1β mRNA expression. Moreover, it significantly suppressed the protein release of IL-6 and IL-10 in a concentration-dependent manner. However, it slightly reduced TNF-α at higher sample concentration (250 μg/mL) without affecting the mRNA expression levels of COX-2 and TNF-α.
CONCLUSIONS: This study suggests that S. ferruginea parasitizing on Tecoma stans exerted anti-inflammatory capability attributed to inhibition of iNOS and IL-1β mRNA expression, NO creation, IL-1β, IL-6, IL-10, and TNF-α protein production, indicating this plant might be a useful plant-derived candidate against inflammation.
Fulltext Quality of Dabai Pulp Oil Extracted by Supercritical Carbon Dioxide and Supplementation in Hypercholesterolemic Rat-A New Alternative Fat

Kadir NAAA, Azlan A, Abas F, Ismail IS

Foods, 2021 Jan 27;10(2).
PMID: 33513823 DOI: 10.3390/foods10020262

Dabai pulp oil (DPO) is new oil extracted from the pulp of Canarium odontophyllum. The quality and efficacy of DPO are needed to promote its potential as a new alternative fat. Therefore, we investigate the quality of DPO, which includes moisture and volatile content (MVC), free fatty acid content (FFA), iodine value (IV), and peroxide value (PV). Furthermore, we evaluate the efficacy of DPO against hypercholesterolemia elicited by a high-cholesterol diet in rats. The MVC of DPO was <0.001 ± 0.00%. Next, the FFA in DPO was 2.57 ± 0.03%, and the IV of DPO was 53.74 ± 0.08 g iodine/100 g oil. Meanwhile, the PV of DPO was 4.97 ± 0.00 mEq/kg. Supplementation of DPO in hypercholesterolemic rats for 30 days revealed the hypocholesterolemic effect (significant reduction of total cholesterol, triglyceride, and 3-hydroxy-3-methylglutaryl-CoA reductase) accompanied by a significant reduction of inflammatory markers (C-reactive protein, interleukin-6 and tumour necrosis factor-α), and lipid peroxidation (MDA). We also observed a significant improvement of lipoprotein lipase (LPL) and antioxidant capacities (total antioxidant status, superoxide dismutase, glutathione peroxidase, and catalase) of the rats. The results on the quality and efficacy of locally made DPO suggest its potential use as a healthy alternative fat in the future.
Fulltext Hepatoprotective Effect of Supercritical Carbon Dioxide Extracted Dabai Pulp Oil and Its Defatted Pulp

Kadir NAAA, Azlan A, Abas F, Ismail IS

Molecules, 2021 Jan 28;26(3).
PMID: 33525363 DOI: 10.3390/molecules26030671

All food scientists must utilize plants for their application as functional foods to reduce hypercholesterolemia incidence through diet. Canarium odontophyllum (dabai) is a novel source for new healthy oil and functional foods. In this work, we evaluate the hepatoprotective effects of supercritical carbon dioxide (SC-CO2) extracted dabai pulp oil (DPO) and defatted dabai pulp (DDP) against hypercholesterolemia elicited by a high-cholesterol diet in rats. Our results show that DPO and DDP supplementation exerted beneficial hypocholesterolemic effects against the high-cholesterol diet-fed rat. Nevertheless, supplementation with DDP revealed superior total cholesterol, low-density lipoprotein, and HMG-CoA reductase lowering efficacy (p < 0.05). Supplementation of either DPO or DDP did not significantly affect AST and ALT levels than normal rats (p > 0.05). Therefore, DDP and DPO are considered as having no toxicological significance. The histological section of rats treated with DPO and DDP showed improved steatosis in hepatocytes. HPLC analysis revealed that DPO and DDP contained syringic acid, which plays an important role in the beneficial effect. In conclusion, our results support the hypocholesterolemic and hepatoprotective effects of DPO and DDP in the hypercholesterolemic rats model.
Fulltext Effect of Defatted Dabai Pulp Extract in Urine Metabolomics of Hypercholesterolemic Rats

Kadir NAAA, Azlan A, Abas F, Ismail IS

Nutrients, 2020 Nov 14;12(11).
PMID: 33202660 DOI: 10.3390/nu12113511

A source of functional food can be utilized from a source that might otherwise be considered waste. This study investigates the hypocholesterolemic effect of defatted dabai pulp (DDP) from supercritical carbon dioxide extraction and the metabolic alterations associated with the therapeutic effects of DDP using 1H NMR urinary metabolomic analysis. Male-specific pathogen-free Sprague-Dawley rats were fed with a high cholesterol diet for 30 days to induce hypercholesterolemia. Later, the rats were administered with a 2% DDP treatment diet for another 30 days. Supplementation with the 2% DDP treatment diet significantly reduced the level of total cholesterol (TC), triglyceride, low-density lipoprotein (LDL), and inflammatory markers (C-reactive protein (CRP), interleukin 6 (IL6) and tumour necrosis factor-α (α-TNF)) and significantly increased the level of antioxidant profile (total antioxidant status (TAS), superoxide dismutase (SOD), glutathione peroxide (GPX), and catalase (CAT)) compared with the positive control group (PG) group (p < 0.05). The presence of high dietary fibre (28.73 ± 1.82 g/100 g) and phenolic compounds (syringic acid, 4-hydroxybenzoic acid and gallic acid) are potential factors contributing to the beneficial effect. Assessment of 1H NMR urinary metabolomics revealed that supplementation of 2% of DDP can partially recover the dysfunction in the metabolism induced by hypercholesterolemia via choline metabolism. 1H-NMR-based metabolomic analysis of urine from hypercholesterolemic rats in this study uncovered the therapeutic effect of DDP to combat hypercholesterolemia.
Chrotacumines G-J, chromone alkaloids from Dysoxylum acutangulum with osteoclast differentiation inhibitory activity

Morita H, Nugroho AE, Nagakura Y, Hirasawa Y, Yoshida H, Kaneda T, et al.

Bioorg Med Chem Lett, 2014 Jun 1;24(11):2437-9.
PMID: 24767841 DOI: 10.1016/j.bmcl.2014.04.020

Four new chromone alkaloids, chrotacumines G-J (1-4), have been isolated from the barks of Dysoxylum acutangulum. Their structures and absolute configurations were elucidated on the basis of NMR and CD data. Chrotacumines G and J (1 and 4) showed osteoclast differentiation inhibitory activity in a dose dependent manner.
Fulltext Complementary Analytical Platforms of NMR Spectroscopy and LCMS Analysis in the Metabolite Profiling of Isochrysis galbana

Bustamam MSA, Pantami HA, Azizan A, Shaari K, Min CC, Abas F, et al.

Mar Drugs, 2021 Mar 02;19(3).
PMID: 33801258 DOI: 10.3390/md19030139

This study was designed to profile the metabolites of Isochrysis galbana, an indigenous and less explored microalgae species. 1H Nuclear Magnetic Resonance (NMR) spectroscopy and Liquid Chromatography-Mass Spectrometry (LCMS) were used to establish the metabolite profiles of five different extracts of this microalga, which are hexane (Hex), ethyl acetate (EtOAc), absolute ethanol (EtOH), EtOH:water 1:1 (AqE), and 100% water (Aq). Partial least square discriminant analysis (PLS-DA) of the generated profiles revealed that EtOAc and Aq extracts contain a diverse range of metabolites as compared to the other extracts with a total of twenty-one metabolites, comprising carotenoids, polyunsaturated fatty acids, and amino acids, that were putatively identified from the NMR spectra. Meanwhile, thirty-two metabolites were successfully annotated from the LCMS/MS data, ten of which (palmitic acid, oleic acid, α-linolenic acid, arachidic acid, cholesterol, DHA, DPA, fucoxanthin, astaxanthin, and pheophytin) were similar to those present in the NMR profile. Another eleven glycerophospholipids were discovered using MS/MS-based molecular network (MN) platform. The results of this study, besides providing a better understanding of I.galbana's chemical make-up, will be of importance in exploring this species potential as a feed ingredient in the aquaculture industry.
Fulltext Preliminary Evaluation of Supercritical Carbon Dioxide Extracted Dabai Pulp Oleoresin as a New Alternative Fat

Kadir NAAA, Azlan A, Abas F, Ismail IS

Molecules, 2021 Sep 13;26(18).
PMID: 34577016 DOI: 10.3390/molecules26185545

There has been growing interest among food scientists in producing a toxin-free fat as an end product with varying physical or nutritional properties of interest to the food industry. Oleoresin is a rich source of bioactive compounds which consumers can easily add to a large variety of food. Dabai (Canarium odontophyllum) pulp oleoresin (DPL) was extracted using supercritical carbon dioxide (SC-CO2) extraction, a green extraction technology. This study investigates the quality of SC-CO2 extracted DPL in discovering its potential as a new alternative fat. The extraction experiment was carried out at a pressure of 40 MPa and a temperature of 40 °C. DPL is a saturated fatty acid (SFA)-rich fat due to its high SFA composition (47.72 ± 0.01%). In addition, the low content of peroxide value (PV) (5.60 ± 0.09 mEq/kg) and free fatty acids (FFA) (3.40 ± 0.03%) indicate the quality and stability of DPL for various applications besides food consumption. DPL also has a low slip melting point (SMP) (20.20 ± 0.03 °C), and HPLC-FID revealed that DPL contained 0.13 ± 0.02 mg/100 g of vitamin E (α-tocopherol), indicating its potential application as a solid fat with a bioactive compound. This present work demonstrates the possible prospect of DPL in the formulation of end products for food industries.
Research updates on the clinical implication of long noncoding RNA in digestive system cancers and chemoresistance

Miao X, Wang F, Wang T, Razak SRA, Yunus MA, Ismail IS

3 Biotech, 2021 Sep;11(9):423.
PMID: 34603923 DOI: 10.1007/s13205-021-02971-w

Long noncoding RNAs (lncRNAs) are implicated in various biological processes, such as cell proliferation, differentiation, apoptosis, migration, and invasion. They are also key players in various biological pathways. LncRNA was considered as 'translational noise' before 1980s. It has been reported that lncRNAs are aberrantly expressed in different cancers, either as oncogene or tumor suppressor gene. Therefore, more and more lncRNAs are recognized as potential diagnostic biomarkers and/or therapeutic targets. As competitive endogenous RNA, lncRNAs can interact with microRNA to alter the expression of target genes, which may have extensive clinical implications in cancers, including diagnosis, treatment, prognosis, and chemoresistance. This review comprehensively summarizes the functions and clinical relevance of lncRNAs in digestive system cancers, especially as a potential tool to overcome chemoresistance.
Fulltext Comparison of adults with insulin resistance (IR) in latent autoimmune diabetes versus IR in glutamic acid decarboxylase antibody-negative diabetes

Salem SD, Saif-Ali R, Muniandy S, Al-Hamodi Z, Ismail IS

Ann Acad Med Singap, 2014 Feb;43(2):107-12.
PMID: 24652431

INTRODUCTION: Insulin resistance in latent autoimmune diabetes in adults (LADA) patients is controversial. The aim of this study was to evaluate insulin resistance and its related factors (metabolic syndrome parameters) among subjects with LADA and glutamic acid decarboxylase antibodies (GADA) negative diabetes, as well as the impact of these factors on insulin resistance.

MATERIALS AND METHODS: GADA levels were investigated in 1140 diabetic patients aged between 30 and 70 years. Insulin resistance and metabolic syndrome parameters were assessed in LADA and GAD-negative diabetic patients by general linear model. In addition, the impact of metabolic syndrome factors on insulin resistance was assessed in LADA and glutamic acid decarboxylase (GAD)-negative diabetic patients.

RESULTS: LADA was diagnosed in 33 subjects from 1140 Malaysian diabetic patients (prevalence = 2.9%). The results showed that LADA patients had higher insulin resistance and high density lipoprotein cholesterol (HDLc) (P = 0.003 and 0.00017 respectively) and lower body mass index (BMI) (P = 0.007) compared to GAD-negative diabetic patients. The HDLc was associated with decreased insulin resistance in LADA patients (P = 0.041), whereas HbA1c, triacylglycerides (TG) and waist were associated with increased insulin resistance in GAD-negative diabetic patients (P = 3.6×10⁻¹², 1.01×10⁻⁵ and 0.004 respectively). HbA1c was highly associated with decreasing β-cell function in both LADA (P = 0.009) and GAD-negative diabetic subjects (P = 2.2×10⁻²⁸).

CONCLUSION: Insulin resistance is significantly higher in LADA than GAD-negative diabetic Malaysian subjects.
Immunomodulatory effects of Isochrysis galbana incorporated diet on Oreochromis sp. (red hybrid tilapia) via Sera-1H NMR metabolomics study

Ahamad Bustamam MS, Pantami HA, Shaari K, Min CC, Mediani A, Ismail IS

Fish Shellfish Immunol, 2023 Jan;132:108455.
PMID: 36464078 DOI: 10.1016/j.fsi.2022.108455

Tilapia is one of the most common fish species that is intensively produced all over the world. However, significant measures at improving aquaculture health must be taken since disease outbreaks are often encountered in the rapidly developing aquaculture industry. Therefore, the objective of the study was designed to evaluate the metabolite changes in tilapia' sera through 1H NMR metabolomics in identifying the potential biomarkers responsible for immunomodulatory effect by the indigenous species of Malaysian microalgae Isochrysis galbana (IG). The results showed that IG-incorporated diet mainly at 5.0% has improved the immune response of innate immunity as observed in serum bactericidal activity (SBA) and serum lysozyme activity (SLA). The orthogonal partial least squares (OPLS) analysis indicated 5 important metabolites significantly upregulated namely as ethanol, lipoprotein, lipid, α-glucose and unsaturated fatty acid (UFA) in the 5.0% IG-incorporated diet compared to control. In conclusion, this study had successfully determined IG in improving aquaculture health through its potential use as an immune modulator. This work also demonstrated the effective use of metabolomics approach in the development of alternative nutritious diet from microalgae species to boost fish health in fulfilling the aquaculture's long-term goals.
Fulltext Classification of Raw Stingless Bee Honeys by Bee Species Origins Using the NMR- and LC-MS-Based Metabolomics Approach

Razali MTA, Zainal ZA, Maulidiani M, Shaari K, Zamri Z, Mohd Idrus MZ, et al.

Molecules, 2018 Aug 28;23(9).
PMID: 30154302 DOI: 10.3390/molecules23092160

The official standard for quality control of honey is currently based on physicochemical properties. However, this method is time-consuming, cost intensive, and does not lead to information on the originality of honey. This study aims to classify raw stingless bee honeys by bee species origins as a potential classifier using the NMR-LCMS-based metabolomics approach. Raw stingless bee honeys were analysed and classified by bee species origins using proton nuclear magnetic resonance (¹H-NMR) spectroscopy and an ultra-high performance liquid chromatography-quadrupole time of flight mass spectrometry (UHPLC-QTOF MS) in combination with chemometrics tools. The honey samples were able to be classified into three different groups based on the bee species origins of Heterotrigona itama, Geniotrigona thoracica, and Tetrigona apicalis. d-Fructofuranose (H. itama honey), β-d-Glucose, d-Xylose, α-d-Glucose (G. thoracica honey), and l-Lactic acid, Acetic acid, l-Alanine (T. apicalis honey) ident d-Fructofuranose identified via ¹H-NMR data and the diagnostic ions of UHPLC-QTOF MS were characterized as the discriminant metabolites or putative chemical markers. It could be suggested that the quality of honey in terms of originality and purity can be rapidly determined using the classification technique by bee species origins via the ¹H-NMR- and UHPLC-QTOF MS-based metabolomics approach.
Dietary supplementation of Polygonum chinense improves the immunity of Asian seabass, Lates calcarifer (Bloch, 1790) against Vibrio harveyi infection

Rashidah AR, Shariff M, Yusoff FM, Ismail IS

Fish Shellfish Immunol Rep, 2023 Dec 15;5:100118.
PMID: 37822351 DOI: 10.1016/j.fsirep.2023.100118

Aquaculture plays a significant role in the overall fish production in Malaysia, contributing a substantial quantity of food-fish amounting to roughly 573,683 tonnes with an estimated economic value of US$860 million in 2022. However, diseases have become a significant limitation for aquaculture production. Therefore, herbal immunostimulant has been considered a natural and practical approach of preventing disease infection in fish. The ability of Polygonum chinense extract (PCE) on haemato-biochemistry parameters, immunomodulatory properties, and disease resistance of Lates calcarifer (Asian seabass) under Vibrio harveyi challenge was evaluated in this study, with a focus on dose-response associations and variability over various exposure durations (0-, 7- and 14-day post-infection). A total of 480 Asian seabass (9.5 ± 0.2 g) were distributed in 12 aquaria and fed four diets supplemented with 0 (control), 2, 5 and 10 g/kg diet for 60 days before being challenged with V. harveyi. Dietary PCE significantly improved (P < 0.05) survival, with the dose of 10 g/kg showing the highest survival rate (90 %) when compared to the control (60 %). Additionally, hematological (red and white blood cell counts, hemoglobulin, packed cell volume, and mean corpuscular volume) and immunological (activities of lysozyme, phagocytic activity and respiratory burst, and serum total immunoglobulin) properties were significantly increased (P < 0.05) in comparison to the control group. In contrast, serum aspartate aminotransferase and alanine aminotransferase levels, as well as glucose level were significantly reduced (P < 0.05) in PCE-fed fish compared to the control group. Conclusively, the current study discovered that supplementing fish feed with P. chinense extract improves fish haemato-biochemical profile, immunocompetence and disease resistance to V. harveyi infection.
Fulltext Effects of a Community-Based Healthy Lifestyle Intervention Program (Co-HELP) among Adults with Prediabetes in a Developing Country: A Quasi-Experimental Study

Ibrahim N, Ming Moy F, Awalludin IA, Mohd Ali Z, Ismail IS

PLoS One, 2016;11(12):e0167123.
PMID: 27935988 DOI: 10.1371/journal.pone.0167123

BACKGROUND: The prevalence of type 2 diabetes among Malaysian adults has increased by more than two folds over the past two decades. Strategies to collaborate with the existing community partners may become a promising channel for wide-scale dissemination of diabetes prevention in the country. The objectives of this study were to determine the effects of community-based lifestyle interventions delivered to adults with prediabetes and their health-related quality of life as compared to the usual care group.
METHODS: This was a quasi-experimental study conducted in two sub-urban communities in Seremban, Malaysia. A total of 268 participants with prediabetes aged between 18 to 65 years old were assigned to either the community-based lifestyle intervention (Co-HELP) (n = 122) or the usual care (n = 146) groups. The Co-HELP program was delivered in partnership with the existing community volunteers to incorporate diet, physical activity, and behaviour modification strategies. Participants in the Co-HELP group received twelve group-based sessions and two individual counselling to reinforce behavioural change. Participants in the usual care group received standard health education from primary health providers in the clinic setting. Primary outcomes were fasting blood glucose, 2-hour plasma glucose, and HbA1C. Secondary outcomes included weight, BMI, waist circumference, total cholesterol, triglyceride, LDL cholesterol, HDL cholesterol, systolic and diastolic blood pressure, physical activity, diet, and health-related quality of life (HRQOL).
RESULTS: An intention-to-treat analysis of between-groups at 12-month (mean difference, 95% CI) revealed that the Co-HELP participants' mean fasting plasma glucose reduced by -0.40 mmol/l (-0.51 to -0.28, p<0.001), 2-hour post glucose by -0.58 mmol/l (-0.91 to -0.24, p<0.001), HbA1C by -0.24% (-0.34 to -0.15, p<0.001), diastolic blood pressure by -2.63 mmHg (-3.79 to -1.48, p<0.01), and waist circumference by -2.44 cm (-4.75 to -0.12, p<0.05) whereas HDL cholesterol increased by 0.12 mmol/l (0.05 to 0.13, p<0.01), compared to the usual care group. Significant improvements were also found in HRQOL for both physical component (PCS) by 6.51 points (5.21 to 7.80, p<0.001) and mental component (MCS) by 7.79 points (6.44 to 9.14, p<0.001). Greater proportion of participants from the Co-HELP group met the clinical recommended target of 5% or more weight loss from the initial weight (24.6% vs 3.4%, p<0.001) and physical activity of >600 METS/min/wk (60.7% vs 32.2%, p<0.001) compared to the usual care group.
CONCLUSIONS: This study provides evidence that a culturally adapted diabetes prevention program can be implemented in the community setting, with reduction of several diabetes risk factors and improvement of HRQOL. Collaboration with existing community partners demonstrated a promising channel for the wide-scale dissemination of diabetes prevention at the community level. Further studies are required to determine whether similar outcomes could be achieved in communities with different socioeconomic backgrounds and geographical areas.
TRIAL REGISTRATION: IRCT201104106163N1.
Fulltext Production and differential activity of recombinant human wild-type G6PD and G6PDViangchan

Vengidasan L, Yunus MA, Yusoff NM, Yahaya BH, Ismail IS

Asian Biomed (Res Rev News), 2020 Aug;14(4):159-167.
PMID: 37551388 DOI: 10.1515/abm-2020-0023

BACKGROUND: Glucose-6-phosphate dehydrogenase (G6PD) is essential to produce reduced nicotinamide adenine dinucleotide phosphate, which is required to protect cells against oxidative stress. G6PD deficiency is a genetic variation that may lead to hemolysis with potential consequences, such as kidney failure, and patients often experience low quality of life.
OBJECTIVES: To establish a simple, efficient, and optimized method to produce a G6PDViangchan variant and characterize the phenotypes of recombinant human wild-type G6PD and G6PDViangchan.
METHODS: G6PD was amplified by polymerase chain reaction (PCR) from a human cDNA plasmid, and the gene for G6PDViangchan was amplified by initiating a mutation at location 871 (G>A) through site-directed mutagenesis. Protein expression and western blotting were conducted after successful cloning. The enzymatic activity of both proteins was assessed spectrophotometrically after purification.
RESULTS: Both amplicons were successfully cloned into a pET26b(+) expression vector and transformed into Escherichia coli BL21 (DE3) cells for overexpression as C-terminally histidine-tagged recombinant proteins. Western blotting confirmed that both proteins were successfully produced at similar levels. The enzymes were purified by immobilized metal (Co) affinity chromatography. Postpurification assay of enzyme activity revealed about 2-fold differences in the levels of specific activity between the wild-type G6PD (155.88 U/mg) and G6PDViangchan (81.85 U/mg), which is consistent with earlier reports. Analysis in silico showed that the coding change in G6PDViangchan has a substantial effect on protein folding structure.
CONCLUSIONS: We successfully cloned, expressed, and purified both wild-type G6PD and G6PDViangchan proteins. Such a protocol may be useful for creating a model system to study G6PD deficiency disease.
Fulltext Solvent Extraction and Identification of Active Anticariogenic Metabolites in Piper cubeba L. through ¹H-NMR-Based Metabolomics Approach

Raja Mazlan RNA, Rukayadi Y, Maulidiani M, Ismail IS

Molecules, 2018 Jul 16;23(7).
PMID: 30012946 DOI: 10.3390/molecules23071730

The aim of this study was to determine the effects of different solvents for extraction, liquid⁻liquid partition, and concentrations of extracts and fractions of Piper cubeba L. on anticariogenic; antibacterial and anti-inflammatory activity against oral bacteria. Furthermore, ¹H-Nuclear Magnetic Resonance (NMR) coupled with multivariate data analysis (MVDA) was applied to discriminate between the extracts and fractions and examine the metabolites that correlate to the bioactivities. All tested bacteria were susceptible to Piper cubeba L. extracts and fractions. Different solvents extraction, liquid⁻liquid partition and concentrations of extracts and fractions have partially influenced the antibacterial activity. MTT assay showed that P. cubeba L. extracts and fractions were not toxic to RAW 264.7 cells at selected concentrations. Anti-inflammatory activity evaluated by nitric oxide (NO) production in lipopolysaccharide (LPS) stimulated cells showed a reduction in NO production in cells treated with P. cubeba L. extracts and fractions, compared to those without treatment. Twelve putative metabolites have been identified, which are (1) cubebin, (2) yatein, (3) hinokinin, (4) dihydrocubebin, (5) dihydroclusin, (6) cubebinin, (7) magnosalin, (8) p-cymene, (9) piperidine, (10) cubebol, (11) d-germacrene and (12) ledol. Different extraction and liquid⁻liquid partition solvents caused separation in principal component analysis (PCA) models. The partial least squares (PLS) models showed that higher anticariogenic activity was related more to the polar solvents, despite some of the active metabolites also present in the non-polar solvents. Hence, P. cubeba L. extracts and fractions exhibited antibacterial and anti-inflammatory activity and have potential to be developed as the anticariogenic agent.
Fulltext Metabolite Profiles of Red and Yellow Watermelon (Citrullus lanatus) Cultivars Using a 1H-NMR Metabolomics Approach

Sulaiman F, Ahmad Azam A, Ahamad Bustamam MS, Fakurazi S, Abas F, Lee YX, et al.

Molecules, 2020 Jul 15;25(14).
PMID: 32679913 DOI: 10.3390/molecules25143235

Watermelon, a widely commercialized fruit, is famous for its thirst-quenching property. The broad range of cultivars, which give rise to distinct color and taste, can be attributed to the differences in their chemical profile, especially that of the carotenoids and volatile compounds. In order to understand this distribution properly, water extracts of red and yellow watermelon pulps with predominantly polar metabolites were subjected to proton nuclear magnetic resonance (1H-NMR) analysis. Deuterium oxide (D2O) and deuterated chloroform (CDCl3) solvents were used to capture both polar and non-polar metabolites from the same sample. Thirty-six metabolites, of which six are carotenoids, were identified from the extracts. The clustering of the compounds was determined using unsupervised principal component analysis (PCA) and further grouping was achieved using supervised orthogonal partial least squares discriminant analysis (OPLS-DA). The presence of lycopene, β-carotene, lutein, and prolycopene in the red watermelon plays an important role in its differentiation from the yellow cultivar. A marked difference in metabolite distribution was observed between the NMR solvents used as evidenced from the PCA model. OPLS-DA and relative quantification of the metabolites, on the other hand, helped in uncovering the discriminating metabolites of the red and yellow watermelon cultivars from the same solvent system.
Fulltext Potency of Selected Berries, Grapes, and Citrus Fruit as Neuroprotective Agents

Tan SJ, Ismail IS

Evid Based Complement Alternat Med, 2020;2020:3582947.
PMID: 32565853 DOI: 10.1155/2020/3582947

A healthy diet should nourish the brain with essential nutrients, including bioactive compounds, for normal brain functioning and to protect it from the negative effects of inflammation and oxidative stress. In this review, a concise summation of the protective effects of selected fruits, namely, berries, grapes, and citrus fruits, against neurological disorder is presented. The focus is on the neuroprotective potential of these fruits against neurodegenerative and mental disorders. The fruits selection was based on the vast reported pharmacological studies on their neuroprotection efficacies. Hence, the respective knowledge and limitations are discussed based on the biological and pharmacological evidence compiled from the previously reported laboratory, epidemiology, and intervention trials.
Fulltext Association of Protein Tyrosine Phosphatase Receptor Type D and Serine Racemase Genetic Variants with Type 2 Diabetes in Malaysian Indians

Saif-Ali R, Al-Hamodi Z, Salem SD, Al-Habori M, Al-Dubai SA, Ismail IS

Indian J Endocrinol Metab, 2024;28(1):55-59.
PMID: 38533286 DOI: 10.4103/ijem.ijem_209_23

INTRODUCTION: Type 2 diabetes (T2D) candidate genes, protein tyrosine phosphatase receptor type D (PTPRD), and serine racemase (SRR) were suggested by a genome-wide association study (GWAS) in the Chinese population. Association studies have been replicated among East Asian populations. The association of PTPRD and SRR genetic variants with T2D in Southeast Asian populations still needs to be studied. This study aimed to investigate the association of PTPRD and SSR genetic variants with T2D in Malaysian Indian subjects.
METHODS: The single nucleotide polymorphisms (SNPs) of PTPRD (rs649891 and rs17584499) and SRR (rs4523957, rs391300, and rs8081273) were genotyped in 397 T2D and 285 normal Malaysian Indian subjects.
RESULTS: The homozygous dominant genotype of rs17584499 is frequent in diabetic patients (56.5%) compared to normal subjects (47.3%). In contrast, the homozygous recessive genotype of rs8081273 is more frequent among normal subjects (12.5%) than diabetic patients (5.6%). The dominant genetic model showed that PTPRD rs17584499 (CC) is a risk factor for T2D (OR = 1.42, P = 0.029), whereas the recessive genetic model showed that SRS SNP rs8081273 was protective for T2D (OR = 0.42, P = 0.003).
CONCLUSION: This study confirmed the association of PTPRD rs17584499 genetic variations with T2D in Malaysian Indians. While the SRR rs8081273 (TT) genotype showed protection against T2D, more investigation in different populations is required to confirm this protection.

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links