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Fulltext Embelin Prevents Seizure and Associated Cognitive Impairments in a Pentylenetetrazole-Induced Kindling Zebrafish Model

Kundap UP, Paudel YN, Kumari Y, Othman I, Shaikh MF

Front Pharmacol, 2019;10:315.
PMID: 31057394 DOI: 10.3389/fphar.2019.00315

Epilepsy is a neuronal disorder associated with several neurological and behavioral alterations characterized by recurrent spontaneous epileptic seizures. Despite having more than 20 anti-epileptic drugs (AEDs), they only provide a symptomatic treatment. As well as, currently available AEDs also displayed cognitive alterations in addition to retarding seizure. This leads to the need for exploring new molecules that not only retard seizure but also improve cognitive impairment. Embelin (EMB) is a benzoquinone derivative which has already demonstrated its pharmacological potentials against arrays of neurological conditions. The current study developed a chronic kindling model in adult zebrafish by using repeated administration of small doses of pentylenetetrazole (PTZ) and a single dose of Kainic acid (KA) to investigate the associated memory impairment. This has been done by using the three-axis maze which is a conventional method to test the learning ability and egocentric memory in zebrafish. As well as, the ameliorative potential of EMB has been evaluated against chronic epilepsy-related memory alterations. Moreover the expression level of pro-inflammatory genes such as C-C motif ligand 2 (CCL2), toll-like receptor-4 (TLR4), tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1) and interferon-γ (IFN-γ) were evaluated. The level of several neurotransmitters such as γ-aminobutyric acid (GABA), acetylcholine (Ach) and glutamate (Glu) was evaluated by liquid chromatography-mass spectrometry (LC-MS). The results showed that daily dose of PTZ 80 mg/kg for 10 days successfully induces a kindling effect in zebrafish, whereas the single dose of KA did not. As compared to control, the PTZ and KA group demonstrates impairment in memory as demonstrated by the three-axis maze. The PTZ group treated with a series of EMB doses (ranging from 0.156 to 0.625 mg/kg) was found to have retarded seizure as well as significantly reduces epilepsy-induced memory alteration. In addition, EMB treatment reduces the expression of inflammatory markers implicating its anti-inflammatory potential. Moreover, levels of GABA, Ach, and glutamate are increased in EMB administered group as compared to the PTZ administered group. Overall, findings demonstrate that EMB might be a potential candidate against chronic epilepsy-related cognitive dysfunction as EMB prevents the seizures, so we expect it to prevent the associated neuroinflammation and learning deficit.

Matched MeSH terms: Chromatography, Liquid
Fulltext Heterometrus Spinifer: An Untapped Source of Anti-Tumor Molecules

Soopramanien M, Khan NA, Ghimire A, Sagathevan K, Siddiqui R

Biology (Basel), 2020 Jul 02;9(7).
PMID: 32630812 DOI: 10.3390/biology9070150

Despite intensive research, cancer incidence and mortality continue to rise. Consequently, the necessity to develop effective anti-cancer therapy is apparent. We have recently shown that the gut bacteria of animals living in polluted environments, such as crocodiles, are a potential source of novel anti-tumor molecules. To extend this work to other resilient species, we investigated the anti-tumor effects of gut bacteria of Heterometrus spinifer (a scorpion). Bacteria from the feces and gut were isolated, identified and evaluated for their anti-tumor effects. Bacterial-conditioned media was prepared in Roswell Park Memorial Institute (RPMI) 1640 media, and cytotoxicity and growth inhibitory properties were examined against cervical (HeLa) cancer cells. Liquid chromatography-mass spectrometry (LC-MS) was conducted to establish the identity of the molecules. Eighteen bacteria species from the gut (HSG01-18) and ten bacteria species from feces (HSF01-10) were tested for anti-tumor effects. Bacterial-conditioned media from scorpion gut and feces exhibited significant growth inhibitory effects against HeLa cells of 66.9% and 83.8%, respectively. Microscopic analysis of cancer cells treated with conditioned media HSG12 and HSG16 revealed apoptosis-like effects. HSG12 was identified as Pseudomonas aeruginosa and HSG16 was identified as Bacillus subtilis. Both conditioned media exhibited 100% growth inhibitory effects versus a selection of cancer cells, comprising cervical, breast and prostate cancer cells. LC-MS indicated the presence of 72 and 38 compounds, detected from HSG12 and HSG16, respectively. Out of these compounds, 47 were successfully identified while the remainder were unidentified and are possibly novel. This study suggests that the fecal and gut microbiota of scorpions might possess molecules with anti-cancer properties, however, further intensive research is needed to assess these expectations.

Matched MeSH terms: Chromatography, Liquid
Combination of light and oxygen accelerates formation of covalent protein-polyphenol bonding during chill storage of meat added 4-methyl catechol

Zainudin MAM, Jongberg S, Lund MN

Food Chem, 2021 Jan 01;334:127611.
PMID: 32712493 DOI: 10.1016/j.foodchem.2020.127611

Plant polyphenols applied as natural antioxidant ingredients, are known to bind to cysteine residues on meat proteins. The aim of this study was to examine the effect of light exposure on the formation of cysteine-phenol adduct in meat added 4-methylcatechol (4MC), a model polyphenol, during storage through quantitative LC-MS/MS-based analysis. Cysteine-4-methylcatechol adduct (Cys-4MC) formation in meat added 1500 ppm 4-MC increased significantly (by 50%) when stored under light in oxygen at 4 °C for 7 days as compared to storage in the dark. This was reflected by a significant decrease in thiol concentrations in the same sample. Gel electrophoresis showed loss in myosin heavy chain (MHC), and a resulting increase in cross-linked MHC (CL-MHC) and larger protein polymers in samples added 4MC. Protein blots stained with nitroblue tetrazolium (NBT) showed intensive protein-polyphenol binding in the meat samples added 4MC, but no major differences between storage conditions.

Matched MeSH terms: Chromatography, Liquid
Fulltext Proteins from Lignosus tigris with selective apoptotic cytotoxicity towards MCF7 cell line and suppresses MCF7-xenograft tumor growth

Kong BH, Teoh KH, Tan NH, Tan CS, Ng ST, Fung SY

PeerJ, 2020;8:e9650.
PMID: 32832273 DOI: 10.7717/peerj.9650

Background: Lignosus tigris, a recently discovered species of the unique Lignosus family, has been traditionally used by the indigenous communities in Peninsular Malaysia to treat various ailments and as an alternative medicine for cancer treatment. The L. tigris cultivar sclerotia (Ligno TG-K) was found to contain numerous bioactive compounds with beneficial biomedicinal properties and the sclerotial extract exhibited potent antioxidant activity. However, the anticancer property of the Ligno TG-K including in vitro and in vivo antitumor effects as well as its anticancer active compounds and the mechanisms has yet to be investigated.
Methods: The cytotoxicity of the Ligno TG-K against human breast (MCF7), prostate (PC3) and lung (A549) adenocarcinoma cell lines was evaluated using MTT cytotoxicity assay. The cytotoxic mechanisms of the active high molecular weight proteins (HMWp) fraction were investigated through detection of caspases activity and apoptotic-related proteins expression by Western blotting. The in vivo antitumor activity of the isolated HMWp was examined using MCF7 mouse xenograft model. Shotgun LC-MS/MS analysis was performed to identify the proteins in the HMWp.
Results and Discussion: Cold water extract of the sclerotia inhibited proliferation of MCF7, A549 and PC3 cells with IC50 ranged from 28.9 to 95.0 µg/mL. Bioassay guided fractionation of the extract revealed that HMWp exhibited selective cytotoxicity against MCF7 cells via induction of cellular apoptosis by the activation of extrinsic and intrinsic signaling pathways. HMWp activated expression of caspase-8 and -9 enzymes, and pro-apoptotic Bax protein whilst inhibiting expression of tumor survivor protein, Bcl-2. HMWp induced tumor-cell apoptosis and suppressed growth of tumor in MCF-7 xenograft mice. Lectins, serine proteases, RNase Gf29 and a 230NA deoxyribonuclease are the major cytotoxic proteins that accounted for 55.93% of the HMWp.
Conclusion: The findings from this study provided scientific evidences to support the traditional use of the L. tigris sclerotia for treatment of breast cancer. Several cytotoxic proteins with high abundance have been identified in the HMWp of the sclerotial extract and these proteins have potential to be developed into new anticancer agents or as adjunct cancer therapy.

Matched MeSH terms: Chromatography, Liquid
Fulltext Purification and characterization of charantin from Momordica charantia Linn.

Oh, J. H., Lim, P. K., Hamzah, S., Tan, C. P., Chan, Sook Wah

Malaysian Journal of Medicine and Health Sciences, 2019;15(102):43-43.
MyJurnal

Introduction: Diabetes mellitus (DM) is one of the top diseases that lead public health concern in Malaysia. It was believed to rise in number up to 4.5 million on cases by year 2020 based on the current figure. Momordica charantia Linn (MC), a climber belonging to family Cucurbitaceae, is well known in treating diabetic-related conditions. In earlier studies related to the hypoglycemic properties of MC mainly utilized the crude extract, which contain a mixture of bioactives (charantins, insulin-like peptides and alkaloids). Till now, there is no conclusive result on the major bioactives that play role in the hypoglycemic effect of MC and research regarding the charantin purification was not well established. Hence, the objectives of this study were to purify the charantin from MC and to characterize the purified charantin before further subjected to in vivo hypoglycemic study. Methods: The crude was first extracted from MC using ethanol as solvent via Soxhlet extraction following by a series of purification steps via washing, centrifugation, and C-18 cartridges. Results: The HPLC analysis showed that the charantin of purified extract after passing out from the cartridge exuded at 12.50 min with a concentration of 500 ppm, which is relatively 20 times higher than the crude extract (25 ppm). The structural properties of purified charantin were studied using FTIR and it showed strong peaks of carboxylic acids (2884 nm), alcohols (1023 nm) and diethyl ether (1114 nm) as compared
with the standard. The compound was reconfirmed in LC-MS analysis. The result displayed mass spectrum in positive mode indicates the presence of similar compound in the purified extract and standard charantin, as presented by ion m/z = 300. Conclusion: The charantin was successfully purified from MC and can act as a potent plant-based hypoglycemic agent for diabetes.

Matched MeSH terms: Chromatography, Liquid
Understanding of the Role of Pretreatment Methods on Rapeseed Oil from the Perspective of Phenolic Compounds

Xu YJ, Jiang F, Song J, Yang X, Shu N, Yuan L, et al.

J Agric Food Chem, 2020 Aug 19;68(33):8847-8854.
PMID: 32806128 DOI: 10.1021/acs.jafc.0c03539

The thermal pretreatment of oilseed prior to oil extraction could increase the oil yield and improve the oil quality. Phenolic compounds are important antioxidants in rapeseed oil. In this study, we investigated the impact of thermal pretreatment method on the rapeseed oil based on phenolic compound levels. Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) analysis showed that the phenolic compound contents in the microwave-pretreated oil were higher than those in the oven- and infrared-treated oils. Sinapic acid (SA) and canolol (CA), which are the top two phenolic compounds in rapeseed oil, exerted well 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity with IC50 values of 8.45 and 8.80 μmol/L. The cell experiment uncovered that SA and CA have significant biological activities related to rapeseed oil quality, including increase of antioxidant enzymes superoxide dismutase (SOD), alleviation of reactive oxygen species (ROS), and cytotoxicity of HepG2 cells after the intake of excessive oleic acid. Further investigation indicated that SA and CA reduced cell apoptosis rate through Bax-Bcl-2-caspase-3 and p53-Bax-Bcl-2-caspase-3, respectively. Taken together, our findings suggest that microwave pretreatment is the best method to improve the content of phenolic compounds in rapeseed oil compared with oven and infrared pretreatments.

Matched MeSH terms: Chromatography, Liquid
Fulltext Global metabolomics profiling of colorectal cancer in Malaysian patients

Amir Hashim NA, Ab-Rahim S, Wan Ngah WZ, Nathan S, Ab Mutalib NS, Sagap I, et al.

Bioimpacts, 2021;11(1):33-43.
PMID: 33469506 DOI: 10.34172/bi.2021.05

Introduction:
The serum metabolomics approach has been used to identify metabolite biomarkers that can diagnose colorectal cancer (CRC) accurately and specifically. However, the biomarkers identified differ between studies suggesting that more studies need to be performed to understand the influence of genetic and environmental factors. Therefore, this study aimed to identify biomarkers and affected metabolic pathways in Malaysian CRC patients.
Methods:
Serum from 50 healthy controls and 50 CRC patients were collected at UKM Medical Centre. The samples were deproteinized with acetonitrile and untargeted metabolomics profile determined using liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QTOFMS, Agilent USA). The data were analysed using Mass Profiler Professional (Agilent, USA) software. The panel of biomarkers determined were then used to identify CRC from a new set of 20 matched samples.
Results:
Eleven differential metabolites were identified whose levels were significantly different between CRC patients compared to normal controls. Based on the analysis of the area under the curve, 7 of these metabolites showed high sensitivity and specificity as biomarkers. The use of the 11 metabolites on a new set of samples was able to differentiate CRC from normal samples with 80% accuracy. These metabolites were hypoxanthine, acetylcarnitine, xanthine, uric acid, tyrosine, methionine, lysoPC, lysoPE, citric acid, 5-oxoproline, and pipercolic acid. The data also showed that the most perturbed pathways in CRC were purine, catecholamine, and amino acid metabolisms.
Conclusion:
Serum metabolomics profiling can be used to identify distinguishing biomarkers for CRC as well as to further our knowledge of its pathophysiological mechanisms.

Matched MeSH terms: Chromatography, Liquid
Fulltext Trace Level Detection of Bisphenol A Analogues and Parabens by LC-MS/MS in Human Plasma from Malaysians

Wiraagni IA, Mohd MA, Rashid RA, Haron DEBM

Biomed Res Int, 2020;2020:2581287.
PMID: 32420332 DOI: 10.1155/2020/2581287

In this study, a novel LC-MS/MS method was designed using a simple extraction procedure that was scientifically developed to capture the most relevant bisphenol A (BPA) analogues (BPB, BPF, BPS, and BPAF) and parabens (propylparaben, ethylparaben, butylparaben, and methylparaben) in human plasma. The LC-MS/MS method was validated using US FDA guidelines, and all validation requirements were satisfactory. This is the method that allows for the detection of plasma bisphenols and parabens in one run and is also the fastest BPA analogue and paraben detection technique for human plasma. The method was used to analyze samples from 150 healthy volunteers from Malaysia who enrolled in the study. No BPB was detected in any of the volunteers; however, 99.3% were positive for BPF. Only 24% and 10.7% of volunteers were positive for BPAF and BPS, respectively. A high percentage of volunteers were negative for propylparaben, ethylparaben, butylparaben, and methylparaben (56%, 68%, 86.7%, and 83.3%, respectively). These results suggest that persons in Malaysia are exposed to different BPA analogues and parabens, from both the daily use of products (cosmetic and plastic products) and the environment.

Matched MeSH terms: Chromatography, Liquid
Molecular description of familial defective APOB-100 in Malaysia

Al-Khateeb AR, Mohd MS, Yusof Z, Zilfalil BA

Biochem Genet, 2013 Oct;51(9-10):811-23.
PMID: 23775634 DOI: 10.1007/s10528-013-9609-6

Familial ligand-defective apolipoprotein B-100 is characterized by elevated plasma low-density lipoprotein levels and premature heart disease. This study aims to determine apolipoprotein B gene mutations among Malaysians with clinical diagnoses of familial hypercholesterolemia and to compare the phenotype of patients with apolipoprotein B gene mutations to those with a low-density lipoprotein receptor gene mutation. A group of 164 patients with a clinical diagnosis of familial hypercholesterolemia was analyzed. Amplicons in exon 26 and exon 29 of the apolipoprotein B gene were screened for genetic variants using denaturing gradient high-performance liquid chromatography; 10 variants were identified. Five novel mutations were detected (p.Gln2485Arg, p.Thr3526Ala, p.Glu3666Lys, p.Tyr4343CysfsX221, and p.Arg4297His). Those with familial defective apolipoprotein had a less severe phenotype than those with familial hypercholesterolemia. An apolipoprotein gene defect is present among Malaysian familial hypercholesterolemics. Those with both mutations show a more severe phenotype than those with one gene defect.

Matched MeSH terms: Chromatography, Liquid
Fulltext LC-MS Data set on the Malayan Deer (Cervus timorensis) Antler Velvet and its antibiofilm activity against Candida species: LC-MS Data set on the Malayan Deer (Cervus timorensis) Antler Velvet and its antibiofilm properties against Candida species

Arzmi MH, John A, Rismayuddin NAR, Kenali NM, Darnis DS

Data Brief, 2021 Apr;35:106769.
PMID: 33537383 DOI: 10.1016/j.dib.2021.106769

Deer antler velvet (DAV) has been traditionally used in Chinese medicine, including treatment on toothache [1]. Due to its rapid and regenerative capacity, deer antlers were proposed to be the good model for bone remodelling in mammals [2]. The data presented in this work is on the liquid chromatography and mass spectrometry (LC-MS) profile and bioactive potential of Malayan deer antler velvet (DAV) on different Candida species that has clinical importance. Aqueous extraction of DAV samples was subjected to Liquid chromatography quadrupole time of flight mass spectrometry (LC-QTOF-MS) profiling. Reverse phase (RP) separation was used due to the process extraction using water as a solvent to separate polar compound. The data was interpreted using Profile Analysis 2.1V. The DAV samples were also tested for the effect on the biofilm formation of seven Candida species in a 96 well plate [3]. The biofilms were developed for 72 h in aerobic environment. Following that, the biofilms biomass was determined using crystal violet assay.

Matched MeSH terms: Chromatography, Liquid
Transcriptomic and Proteomic Analyses of Nepenthes ampullaria and Nepenthes rafflesiana Reveal Parental Molecular Expression in the Pitchers of Their Hybrid, Nepenthes × hookeriana

Zulkapli MM, Ab Ghani NS, Ting TY, Aizat WM, Goh HH

Front Plant Sci, 2020;11:625507.
PMID: 33552113 DOI: 10.3389/fpls.2020.625507

Nepenthes is a genus comprising carnivorous tropical pitcher plants that have evolved trapping organs at the tip of their leaves for nutrient acquisition from insect trapping. Recent studies have applied proteomics approaches to identify proteins in the pitcher fluids for better understanding the carnivory mechanism, but protein identification is hindered by limited species-specific transcriptomes for Nepenthes. In this study, the proteomics informed by transcriptomics (PIT) approach was utilized to identify and compare proteins in the pitcher fluids of Nepenthes ampullaria, Nepenthes rafflesiana, and their hybrid Nepenthes × hookeriana through PacBio isoform sequencing (Iso-Seq) and liquid chromatography-mass spectrometry (LC-MS) proteomic profiling. We generated full-length transcriptomes from all three species of 80,791 consensus isoforms with an average length of 1,692 bp as a reference for protein identification. The comparative analysis found that transcripts and proteins identified in the hybrid N. × hookeriana were more resembling N. rafflesiana, both of which are insectivorous compared with omnivorous N. ampullaria that can derive nutrients from leaf litters. Previously reported hydrolytic proteins were detected, including proteases, glucanases, chitinases, phosphatases, nucleases, peroxidases, lipid transfer protein, thaumatin-like protein, pathogenesis-related protein, and disease resistance proteins. Many new proteins with diverse predicted functions were also identified, such as amylase, invertase, catalase, kinases, ligases, synthases, esterases, transferases, transporters, and transcription factors. Despite the discovery of a few unique enzymes in N. ampullaria, we found no strong evidence of adaptive evolution to produce endogenous enzymes for the breakdown of leaf litter. A more complete picture of digestive fluid protein composition in this study provides important insights on the molecular physiology of pitchers and carnivory mechanism of Nepenthes species with distinct dietary habits.

Matched MeSH terms: Chromatography, Liquid
Fulltext Edible Bird's Nest Supplementation Improves Male Reproductive Parameters of Sprague Dawley Rat

Jaffar FHF, Osman K, Hui CK, Zulkefli AF, Ibrahim SF

Front Pharmacol, 2021;12:631402.
PMID: 33986667 DOI: 10.3389/fphar.2021.631402

Edible bird's nest (EBN) is reported to have a positive in vitro proliferative effect and contain male reproductive hormones. Spermatogonia cells proliferate during spermatogenesis under male reproductive hormones stimulation that include testosterone, follicle-stimulating hormone (FSH), and luteinizing hormone (LH). Characterization of EBN through liquid chromatography-mass spectrometry (LCMS) has found testosterone as a base peak. Six types of amino acids, estradiol and sialic acid were among the major peaks that have been characterized. Based on the presence of these reproductive components, this study evaluated different doses of EBN on sperm parameters and male reproductive hormones of Sprague Dawley rats. Sixteen Sprague Dawley rats at the age of eight weeks were randomly and equally divided into four groups, which are Control, 10 mg/kg BW/d 50 mg/kg BW/d, and 250 mg/kg BW/d EBN group. The rats were fed with EBN enriched pellet daily and water ad-libitum. Rats were sacrificed and the organ was weighed for organ coefficients after eight weeks of treatment. Sperm concentration, percentage of sperm motility, and sperm viability were evaluated. Meanwhile, ELISA method was used to measure testosterone, FSH, and LH. Findings showed that there were no significant differences in organ coefficient between groups. Supplementation of 250 mg/kg BW/d EBN demonstrated a significant increase in sperm concentration, percentage of sperm motility as well as FSH and LH level compared to 10 mg/kg BW/d group. There was a dose-dependent increase in testosterone level but was not significant between groups. Based on these findings, EBN is concluded to have crucial effects on male reproductive parameters.

Matched MeSH terms: Chromatography, Liquid
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.

Matched MeSH terms: Chromatography, Liquid
Fluorescence polarisation for high-throughput screening of adulterated food products via phosphodiesterase 5 inhibition assay

Mohd Yusop AY, Xiao L, Fu S

Drug Test Anal, 2021 May;13(5):953-964.
PMID: 32959983 DOI: 10.1002/dta.2926

The surge in the consumption of food products containing herbal aphrodisiacs has driven their widespread adulteration. A rapid screening strategy is, therefore, warranted to curb this problem. This study established an enzyme inhibition assay to screen phosphodiesterase 5 (PDE5) inhibitors as adulterants in selected food products. Fluorescein-labelled cyclic-3',5'-guanosine monophosphate was utilised as substrates for the PDE5A1 enzyme, aided by the presence of nanoparticle phosphate-binding beads on their fluorescence polarisation. The sample preparation was optimised to improve the enzyme inhibition efficiency and applied to calculate the threshold values of six blank food matrices. The assay was validated using sildenafil, producing an IC50 of 4.2 nM. The applicability of the assay procedure was demonstrated by screening 55 distinct food samples. The results were subsequently verified using confirmatory liquid chromatography-high-resolution mass spectrometry (LC-HRMS) analysis. Altogether, 49 samples inhibited the PDE5 enzyme above the threshold values (75.7%-105.5%) and were registered as potentially adulterated samples. The remaining six samples were marked as nonadulterated with percentage inhibition below the threshold values (-3.3%-18.2%). The LC-HRMS analysis agreed with the assay results for all food products except for the instant coffee premix (ICP) samples. False-positive results were obtained for the ICP samples at 32% (8/25), due to possible PDE5 inhibition by caffeine. Contrarily, all other food samples were found to produce 0% (0/30) false-positive or false-negative results. The broad-based assay, established via a simple mix-incubate-read format, exhibited promising potential for high-throughput screening of PDE5 inhibitors in various food products, except those with naturally occurring phosphodiesterase inhibitors such as caffeine.

Matched MeSH terms: Chromatography, Liquid
Fulltext The differential expression of aqueous soluble proteins in breast normal and cancerous tissues in relation to ethnicity of the patients; Chinese, Malay and Indian

Liang S, Singh M, Gam LH

Dis Markers, 2010;28(3):149-65.
PMID: 20534901 DOI: 10.3233/DMA-2010-0694

Female breast cancer is one of the leading causes of female mortality worldwide. In Malaysia, breast cancer is the most commonly diagnosed cancer in women. Of the women in Malaysia, the Chinese have the highest number of breast cancer cases, followed by the Indian and the Malay. The most common type of breast cancer is infiltrating ductal carcinoma (IDC). A proteomic approach was applied in this study to identify changes in the protein profile of cancerous tissues compared with normal tissues from 18 patients; 8 Chinese, 6 Malay and 4 Indian were analysed. Twenty-four differentially expressed hydrophilic proteins were identified. We evaluated the potential of these proteins as biomarkers for infiltrating ductal carcinoma based on their ethnic-specific expressions. Three of the upregulated proteins, calreticulin, 14-3-3 protein zeta and 14-3-3 protein eta, were found to be expressed at a significantly higher level in the cancerous breast tissues when compared with the normal tissues in cases of infiltrating ductal carcinoma. The upregulation in expression was particularly dominant in the Malay cohort.

Matched MeSH terms: Chromatography, Liquid
Expression of cytosolic and thiolated proteome of Musca domestica larvae under oxidative challenge

Tan YH, Alias Z

Trop Biomed, 2020 Sep 01;37(3):744-755.
PMID: 33612787 DOI: 10.47665/tb.37.3.744

The study was aimed to investigate the expression of cytosolic and thiolated proteins of Musca domestica larvae under oxidative stress. Proteins from acute treatment of hydrogen peroxide (LC50 = 21.52% (v/v)) on 3rd stage larvae of housefly were extracted and purified using an activated Thiol Sepharose® for thiolated protein purification. Two dimensional gel electrophoresis was used for visualizing and analyzing expression of cytosolic and thiolated proteins. Protein spots with more than 5 fold of expression change were identified using liquid chromatography- tandem mass spectrometry (LC-MS/MS). The cytosolic proteins were actin, tropomyosin, ubiquitin, arginine kinase, pheromone binding protein/general odorant binding protein, and ATP: guanidino phosphotransferase. The thiolated proteins with more than 5 fold change in expression as an effect to the acute treatment were fructose bisphosphate aldolase, short chain dehydrogenase and lactate/malate dehydrogenase. The proteins identified in the study should provide vital information for future reference in oxidative stress defence and response occurring in houseflies.

Matched MeSH terms: Chromatography, Liquid
Characterisation of secondary metabolites from Rhinacanthus nasutus L (Kurz) for the identification of novel antibacterial leads

Sheikh HM, Reshi NA

Trop Biomed, 2020 Sep 01;37(3):812-821.
PMID: 33612794 DOI: 10.47665/tb.37.3.812

The bioactivity of R. nasutus leaf extracts was assessed on Bacillus cereus, Bacillus subtilis, Staphylococcus aureus, Streptococcus pyogenes, Vibrio parahaemolyticus, Enterobacter aerogenes, Proteus mirabilis, and Klebsiella pneumoniae. Crude chloroform, petroleum ether, ethyl acetate, ethanol and methanol extracts were screened by disc diffusion method. Promising crude extract was further subjected to the column fractionation followed by the screening of the antibacterial activity of individual fractions. Biologically active pure fraction was subjected to the advanced analytical studies like HPLC, LC-MS, IR and NMR for characterisation of the bioactive compound. Ethanolic extract exhibited the maximum antibacterial activity against Klebsiella pneumoniae with the maximum of 35±0.42 mm zone of inhibition. The biologically potent column fraction from ethanol extract with 40±0.42 mm zone of inhibition upon subject to the HPLC, LC-MS, IR and NMR revealed that the active compound is rhinacanthin-C, a naphthoquinone.

Matched MeSH terms: Chromatography, Liquid
Occurrence of selected estrogenic compounds and estrogenic activity in surface water and sediment of Langat River (Malaysia)

Praveena SM, Lui TS, Hamin N, Razak SQ, Aris AZ

Environ Monit Assess, 2016 Jul;188(7):442.
PMID: 27353134 DOI: 10.1007/s10661-016-5438-5

The occurrence and estrogenic activities of steroid estrogens, such as the natural estrone (E1), 17β estradiol (E2), and estriol (E3), as well as the synthetic 17α-ethynylestradiol (EE2), were investigated in eight sampling points along the Langat River (Malaysia). Surface water samples were collected at 0.5 m and surface sediment 0-5 cm from the river surface. Instrument analysis of steroid estrogens was determined by UPLC-ESI-MS with an ultra-performance liquid chromatograph (Perkin Elmer FX15) coupled to a Q Trap function mass spectrophotometer (model 3200: AB Sciex). Steroid estrogen concentrations were higher in the Langat River sediments than those in its surface water. In surface water, E1 was not detected in any sampling point, E2 was only detected in two midstream sampling points (range 0-0.004 ng/L), E3 in three sampling points (range 0-0.002 ng/L), and EE2 in four sampling points (range 0-0.02 ng/L). E1 and E2 were detected in sediments from all sampling points, E3 in five sampling points, while EE2 only in one midstream sample (3.29E-4 ng/g). Sewage treatment plants, farming waste, and agricultural activities particularly present midstream and downstream were identified as potential sources of estrogens. Estrogenic activity expressed as estradiol equivalents (EEQs) was below 1 ng/L in all samples for both surface water and sediment, indicating therefore a low potential estrogenic risk to the aquatic environment. Although the health risks are still uncertain for drinking water consumers exposed to low levels of steroid estrogen concentrations, Langat River water is unacceptable for direct drinking purposes without treatment. Further studies of endocrine disruptors in Malaysian waters are highly recommended.

Matched MeSH terms: Chromatography, Liquid
Acrylamide formation in vegetable oils and animal fats during heat treatment

Daniali G, Jinap S, Hajeb P, Sanny M, Tan CP

Food Chem, 2016 Dec 01;212:244-9.
PMID: 27374529 DOI: 10.1016/j.foodchem.2016.05.174

The method of liquid chromatographic tandem mass spectrometry was utilized and modified to confirm and quantify acrylamide in heating cooking oil and animal fat. Heating asparagine with various cooking oils and animal fat at 180°C produced varying amounts of acrylamide. The acrylamide in the different cooking oils and animal fat using a constant amount of asparagine was measured. Cooking oils were also examined for peroxide, anisidine and iodine values (or oxidation values). A direct correlation was observed between oxidation values and acrylamide formation in different cooking oils. Significantly less acrylamide was produced in saturated animal fat than in unsaturated cooking oil, with 366ng/g in lard and 211ng/g in ghee versus 2447ng/g in soy oil, followed by palm olein with 1442ng/g.

Matched MeSH terms: Chromatography, Liquid
Fulltext Proteome profiling in the hippocampus, medial prefrontal cortex, and striatum of aging rat

Hamezah HS, Durani LW, Yanagisawa D, Ibrahim NF, Aizat WM, Bellier JP, et al.

Exp Gerontol, 2018 Oct 01;111:53-64.
PMID: 29981398 DOI: 10.1016/j.exger.2018.07.002

Decrease in multiple functions occurs in the brain with aging, all of which can contribute to age-related cognitive and locomotor impairments. Brain atrophy specifically in hippocampus, medial prefrontal cortex (mPFC), and striatum, can contribute to this age-associated decline in function. Our recent metabolomics analysis showed age-related changes in these brain regions. To further understand the aging processes, analysis using a proteomics approach was carried out. This study was conducted to identify proteome profiles in the hippocampus, mPFC, and striatum of 14-, 18-, 23-, and 27-month-old rats. Proteomics analysis using ultrahigh performance liquid chromatography coupled with Q Exactive HF Orbitrap mass spectrometry identified 1074 proteins in the hippocampus, 871 proteins in the mPFC, and 241 proteins in the striatum. Of these proteins, 97 in the hippocampus, 25 in mPFC, and 5 in striatum were differentially expressed with age. The altered proteins were classified into three ontologies (cellular component, molecular function, and biological process) containing 44, 38, and 35 functional groups in the hippocampus, mPFC, and striatum, respectively. Most of these altered proteins participate in oxidative phosphorylation (e.g. cytochrome c oxidase and ATP synthase), glutathione metabolism (e.g. peroxiredoxins), or calcium signaling pathway (e.g. protein S100B and calmodulin). The most prominent changes were observed in the oldest animals. These results suggest that alterations in oxidative phosphorylation, glutathione metabolism, and calcium signaling pathway are involved in cognitive and locomotor impairments in aging.

Matched MeSH terms: Chromatography, Liquid

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