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Fulltext Design of new competitive dengue NS2B/NS3 protease inhibitors-a computational approach

Frimayanti N, Chee CF, Zain SM, Rahman NA

Int J Mol Sci, 2011;12(2):1089-100.
PMID: 21541045 DOI: 10.3390/ijms12021089

Dengue is a serious disease which has become a global health burden in the last decade. Currently, there are no approved vaccines or antiviral therapies to combat the disease. The increasing spread and severity of the dengue virus infection emphasizes the importance of drug discovery strategies that could efficiently and cost-effectively identify antiviral drug leads for development into potent drugs. To this effect, several computational approaches were applied in this work. Initially molecular docking studies of reference ligands to the DEN2 NS2B/NS3 serine protease were carried out. These reference ligands consist of reported competitive inhibitors extracted from Boesenbergia rotunda (i.e., 4-hydroxypanduratin A and panduratin A) and three other synthesized panduratin A derivative compounds (i.e., 246DA, 2446DA and 20H46DA). The design of new lead inhibitors was carried out in two stages. In the first stage, the enzyme complexed to the reference ligands was minimized and their complexation energies (i.e., sum of interaction energy and binding energy) were computed. New compounds as potential dengue inhibitors were then designed by putting various substituents successively on the benzyl ring A of the reference molecule. These substituted benzyl compounds were then computed for their enzyme-ligand complexation energies. New enzyme-ligand complexes, exhibiting the lowest complexation energies and closest to the computed energy for the reference compounds, were then chosen for the next stage manipulation and design, which involved substituting positions 4 and 5 of the benzyl ring A (positions 3 and 4 for 2446DA) with various substituents.

Matched MeSH terms: Serine Proteinase Inhibitors/pharmacology; Serine Proteinase Inhibitors/chemistry*
Synthesis, spectral analysis and biological evaluation of Nalkyl/aralkyl/aryl-4-chlorobenzenesulfonamide derivatives

Rehman A, Abbasi MA, Siddiqui SZ, Mohyuddin A, Nadeem S, Shah SA

Pak J Pharm Sci, 2016 Sep;29(5):1489-1496.
PMID: 27731801

New potent organic compounds were synthesized with an aim of good biological activities such as antibacterial and anti-enzymatic. Three series of sulfonamide derivatives were synthesized by treating N-alkyl/aryl substituted amines (2a-f) with 4-chlorobenzensulfonyl chloride (1) to yield N-alkyl/aryl-4-chlorobenzenesulfonamide(3af) that was then derivatized by gearing up with ethyl iodide (4), benzyl chloride (5) and 4-chlorobenzyl chloride (6) using sodium hydride as base to initialize the reaction in a polar aprotic solvent (DMF) to synthesize the derivatives, 7a-f, 8af and 9a-f respectively. Structure elucidation was brought about by IR, 1H-NMR and EIMS spectra for all the synthesized molecules which were evaluated for their antibacterial activities and inhibitory potentials for certain enzymes.

Matched MeSH terms: Serine Proteinase Inhibitors/chemical synthesis; Serine Proteinase Inhibitors/pharmacology
Recent update on anti-dengue drug discovery

Dighe SN, Ekwudu O, Dua K, Chellappan DK, Katavic PL, Collet TA

Eur J Med Chem, 2019 Aug 15;176:431-455.
PMID: 31128447 DOI: 10.1016/j.ejmech.2019.05.010

Dengue is the most important arthropod-borne viral disease of humans, with more than half of the global population living in at-risk areas. Despite the negative impact on public health, there are no antiviral therapies available, and the only licensed vaccine, Dengvaxia®, has been contraindicated in children below nine years of age. In an effort to combat dengue, several small molecules have entered into human clinical trials. Here, we review anti-DENV molecules and their drug targets that have been published within the past five years (2014-2018). Further, we discuss their probable mechanisms of action and describe a role for classes of clinically approved drugs and also an unclassified class of anti-DENV agents. This review aims to enhance our understanding of novel agents and their cognate targets in furthering innovations in the use of small molecules for dengue drug therapies.

Matched MeSH terms: Serine Proteinase Inhibitors/pharmacology*; Serine Proteinase Inhibitors/chemistry
Fragment-based molecular design of new competitive dengue Den2 Ns2b/Ns3 inhibitors from the components of fingerroot (Boesenbergia rotunda)

Frimayanti N, Zain SM, Lee VS, Wahab HA, Yusof R, Abd Rahman N

In Silico Biol. (Gedrukt), 2011;11(1-2):29-37.
PMID: 22475750 DOI: 10.3233/ISB-2012-0442

Publication year=2011-2012

Matched MeSH terms: Serine Proteinase Inhibitors/chemistry*
Proteomics, functional characterization and antivenom neutralization of the venom of Pakistani Russell's viper (Daboia russelii) from the wild

Faisal T, Tan KY, Sim SM, Quraishi N, Tan NH, Tan CH

J Proteomics, 2018 07 15;183:1-13.
PMID: 29729992 DOI: 10.1016/j.jprot.2018.05.003

The venom proteome of wild Pakistani Russell's viper (Daboia russelii) was investigated through nano-ESI-LCMS/MS of the reverse-phase HPLC fractions. A total of 54 venom proteins were identified and clustered into 11 protein families. Phospholipase A2 (PLA2, 63.8%) and Kunitz-type serine protease inhibitor (KSPI, 16.0%) were most abundant, followed by snake venom serine protease (SVSP, 5.5%, mainly Factor V activating enzyme), vascular endothelial growth factor (VEGF, 4.3%), snake venom metalloproteinase (SVMP, 2.5%, mainly Factor X activating enzyme) and phosphodiesterase (PDE, 2.5%). Other minor proteins include cysteine-rich secretory protein (CRiSP), snake venom C-type lectin/lectin-like protein (snaclec), nerve growth factor, L-amino acid oxidase and 5'-nucleotidase. PLA2, KSPI, SVSP, snaclec and SVMP are hemotoxic proteins in the venom. The study indicated substantial venom variation in D. russelii venoms of different locales, including 3 Pakistani specimens kept in the USA. The venom exhibited potent procoagulant activity on human plasma (minimum clotting dose = 14.5 ng/ml) and high lethality (rodent LD50 = 0.19 μg/g) but lacked hemorrhagic effect locally. The Indian VINS Polyvalent Antivenom bound the venom immunologically in a concentration-dependent manner. It moderately neutralized the venom procoagulant and lethal effects (normalized potency against lethality = 2.7 mg venom neutralized per g antivenom).
BIOLOGICAL SIGNIFICANCE: Comprehensive venom proteomes of D. russelii from different locales will facilitate better understanding of the geographical variability of the venom in both qualitative and quantitative terms. This is essential to provide scientific basis for the interpretation of differences in the clinical presentation of Russell's viper envenomation. The study revealed a unique venom proteome of the Pakistani D. russelii from the wild (Indus Delta), in which PLA2 predominated (~60% of total venom proteins). The finding unveiled remarkable differences in the venom compositions between the wild (present study) and the captive specimens reported previously. The integration of toxicity tests enabled the correlation of the venom proteome with the envenoming pathophysiology, where the venom showed potent lethality mediated through coagulopathic activity. The Indian VINS Polyvalent Antivenom (VPAV) showed binding activity toward the venom protein antigens; however the immunorecognition of small proteins and PLA2-dominating fractions was low to moderate. Consistently, the antivenom neutralized the toxicity of the wild Pakistani Russell's viper venom at moderate efficacies. Our results suggest that it may be possible to enhance the Indian antivenom potency against the Pakistani viper venom by the inclusion of venoms from a wider geographical range including that from Pakistan into the immunogen formulation.

Matched MeSH terms: Serine Proteinase Inhibitors/analysis
Comparative aspects of the care of familial hypercholesterolemia in the "Ten Countries Study"

Pang J, Chan DC, Hu M, Muir LA, Kwok S, Charng MJ, et al.

J Clin Lipidol, 2019 01 25;13(2):287-300.
PMID: 30797720 DOI: 10.1016/j.jacl.2019.01.009

BACKGROUND: There is a lack of information on the health care of familial hypercholesterolemia (FH).
OBJECTIVE: The objective of this study was to compare the health care of FH in countries of the Asia-Pacific region and Southern Hemisphere.
METHODS: A series of questionnaires were completed by key opinion leaders from selected specialist centers in 12 countries concerning aspects of the care of FH, including screening, diagnosis, risk assessment, treatment, teaching/training, and research; the United Kingdom (UK) was used as the international benchmark.
RESULTS: The estimated percentage of patients diagnosed with the condition was low (overall <3%) in all countries, compared with ∼15% in the UK. Underdetection of FH was associated with government expenditure on health care (ϰ = 0.667, P

Matched MeSH terms: Serine Proteinase Inhibitors/pharmacology; Serine Proteinase Inhibitors/therapeutic use
Fulltext Alpha-1 antitrypsin augmentation therapy decreases miR-199a-5p, miR-598 and miR-320a expression in monocytes via inhibition of NFκB

Hassan T, de Santi C, Mooney C, McElvaney NG, Greene CM

Sci Rep, 2017 10 23;7(1):13803.
PMID: 29062067 DOI: 10.1038/s41598-017-14310-2

Alpha-1 antitrypsin (AAT) augmentation therapy involves infusion of plasma-purified AAT to AAT deficient individuals. Whether treatment affects microRNA expression has not been investigated. This study's objectives were to evaluate the effect of AAT augmentation therapy on altered miRNA expression in monocytes and investigate the mechanism. Monocytes were isolated from non-AAT deficient (MM) and AAT deficient (ZZ) individuals, and ZZs receiving AAT. mRNA (qRT-PCR, microarray), miRNA (miRNA profiling, qRT-PCR), and protein (western blotting) analyses were performed. Twenty one miRNAs were differentially expressed 3-fold between ZZs and MMs. miRNA validation studies demonstrated that in ZZ monocytes receiving AAT levels of miR-199a-5p, miR-598 and miR-320a, which are predicted to be regulated by NFκB, were restored to levels similar to MMs. Validated targets co-regulated by these miRNAs were reciprocally increased in ZZs receiving AAT in vivo and in vitro. Expression of these miRNAs could be increased in ZZ monocytes treated ex vivo with an NFκB agonist and decreased by NFκB inhibition. p50 and p65 mRNA and protein were significantly lower in ZZs receiving AAT than untreated ZZs. AAT augmentation therapy inhibits NFκB and decreases miR-199a-5p, miR-598 and miR-320a in ZZ monocytes. These NFκB-inhibitory properties may contribute to the anti-inflammatory effects of AAT augmentation therapy.

Matched MeSH terms: Serine Proteinase Inhibitors