Displaying publications 81 - 100 of 437 in total

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  1. Ke-Xin Yu, Rohani Ahmad, Ching-Lee Wong, Ibrahim Jantan
    MyJurnal
    Introduction: Inhibition of the cholinesterase’s function leads to paralysis and death. This mechanism is served as a common mode of action of insecticide. The three tropical seaweeds, namely Bryopsis pennata, Padina australis and Sargassum binderi were reported for its potential mosquito larvicidal effect. In the present study, these seaweeds were evaluated for their potential as a cholinesterase inhibitor in the mechanism of larvicidal action. Methods: Ace- tylcholinsterase (AChE) inhibition assay was carried out based on the colorimetric method using a microplate reader. Phytochemical content of the seaweed extracts was screened by using liquid chromatography-mass spectroscopy (LC-MS). Results: Green seaweed B. pennata showed the strongest inhibition effect towards in vitro AChE by using
    tissue homogenates of Aedes aegypti (IC50 value = 0.84 mg mL ) and Aedes albopictus as the enzyme source (IC
    -1
    value = 0.92 mg mL-1). The pattern of Lineweaver-Burk plots revealed that B. pennata was a mixed type inhibitor of
    AChE, as the readings of Km, Vmax, Ki and Ki’, indicates that it had a strong inhibition ability with high binding affin- ity towards both free enzyme and enzyme-substrate complex. Conclusion: These findings suggest the compound(s) in
    B. pennata extract serves as a promising source that could be developed into a mosquito larvicidal agent with AChE inhibition effect.
    Matched MeSH terms: Inhibitory Concentration 50
  2. 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: Inhibitory Concentration 50
  3. Dong AN, Ahemad N, Pan Y, Palanisamy UD, Yiap BC, Ong CE
    Curr Mol Pharmacol, 2020;13(3):233-244.
    PMID: 31713493 DOI: 10.2174/1874467212666191111110429
    BACKGROUND: There is a large inter-individual variation in cytochrome P450 2C19 (CYP2C19) activity. The variability can be caused by the genetic polymorphism of CYP2C19 gene. This study aimed to investigate the molecular and kinetics basis for activity changes in three alleles including CYP2C19*23, CYP2C19*24 and CYP2C19*25found in the Chinese population.

    METHODS: The three variants expressed by bacteria were investigated using substrate (omeprazole and 3- cyano-7-ethoxycoumarin[CEC]) and inhibitor (ketoconazole, fluoxetine, sertraline and loratadine) probes in enzyme assays along with molecular docking.

    RESULTS: All alleles exhibited very low enzyme activity and affinity towards omeprazole and CEC (6.1% or less in intrinsic clearance). The inhibition studies with the four inhibitors, however, suggested that mutations in different variants have a tendency to cause enhanced binding (reduced IC50 values). The enhanced binding could partially be explained by the lower polar solvent accessible surface area of the inhibitors relative to the substrates. Molecular docking indicated that G91R, R335Q and F448L, the unique mutations in the alleles, have caused slight alteration in the substrate access channel morphology and a more compact active site cavity hence affecting ligand access and binding. It is likely that these structural alterations in CYP2C19 proteins have caused ligand-specific alteration in catalytic and inhibitory specificities as observed in the in vitro assays.

    CONCLUSION: This study indicates that CYP2C19 variant selectivity for ligands was not solely governed by mutation-induced modifications in the active site architecture, but the intrinsic properties of the probe compounds also played a vital role.

    Matched MeSH terms: Inhibitory Concentration 50
  4. Phirdaous Abbas, Yumi Zuhanis Has-Yun Hashim, Hamzah Mohd Salleh, Saripah Salbiah Syed Abdul Azzizz
    MyJurnal
    Uninfected agarwood branch is readily available as raw material in agarwood plantation as new practices of agarwood plantation scheme were opted as substitute to the endangered wild type agarwood. The uninfected branch can be easily obtained during pruning process (one of plantation’s common maintenance procedure), throughout the years before inoculation stage. This current study aimed to investigate the optimal extraction process conditions of agarwood branch using ethanol as solvent system for maximal yield, and assess its cytotoxic effects towards MCF-7 breast cancer cells. Uninfected branch of Aquilaria subintegra was subjected to One Factor at a Time (OFAT) and Response Surface Methodology (RSM)-guided ethanolic extraction to achieve maximal yield. The extract was then subjected to cytotoxicity, cell attachment and cell viability assays, respectively. Optimization Run 2 (temperature 45 °C, solid-liquid ratio of 1:30, 16 hours maceration) gave the highest agarwood branch ethanolic extract (ABEE) yield of 44.70 ± 18.9 mg/g dried material (DM). Meanwhile Run 7 (temperature 45 °C, solid-liquid ratio of 1:10, 16 hours of maceration) gave the lowest yield (19.34 ± 14.1 mg/g DM). However, while maintaining the 16 hour-maceration, the model predicted a slightly lower yield of 30.232 ± 0.266 mg/g DM of ABEE with process conditions of 45 °C and solid-liquid ratio of 1:19 when the desirable parameters were factored in namely using (ⅰ) the most suitable temperature (that does not risk the bioactivities of the extract), and (ⅱ) an economical volume of solvent. Crude ABEE obtained from the optimal process conditions resulted in cytotoxicity effects on MCF-7 breast cancer cells with IC50 estimate of 3.645 ± 0.099 μg/mL. The extract also affected MCF-7 cell attachment and viability with altered morphology. More work to elucidate the mechanism of actions of the extract are warranted; which could further lead to development of breast cancer natural product-based therapeutics.
    Matched MeSH terms: Inhibitory Concentration 50
  5. Abdelkader Hassani, Siti Aslina Hussain?, Abdullah, N., Suryani Kamarudin, Rozita Rosli
    MyJurnal
    The present work investigated the antioxidant properties and antihypertensive activity of
    magnesium orotate (MgOr) using various established in vitro assays, such as β-carotene
    bleaching activity, 1,1-diphenyl-2-picrylhydrazyl (DPPH), and nitric oxide scavenging activity as well as angiotensin converting enzyme (ACE) inhibitory activity. Magnesium orotate
    nanoparticles (MgOrGANPs) were prepared using the gum arabic (GA) as stabiliser coatings
    for nanoparticles through freeze-drying method. The in vitro cytoxicity of MgOrGANPs
    against human breast cancer MCF7, liver cancer HepG2, and colon cancer HT29 was investigated. The nitric oxide (NO) and DPPH scavenging assays of MgOrGANPs showed a
    dose-dependent trend, while 500 and 200 µL/mL were significantly more effective than the
    other concentrations with an IC50 of 89.56 µg/mL and 63.22% DPPH scavenging capacity
    respectively. The exposure of human cancer cells to MgOrGANPs at 1.56 – 1,000 µg/mL
    using 3-)4,5-dimethylthiazol-2-yl(2,5-diphenyl tetrazolium bromide (MTT) inhibited the
    growth of cell lines examined in a dose-dependent manner. Hence, MgOrGANPs may have
    great potential to be applied for cancer treatments.
    Matched MeSH terms: Inhibitory Concentration 50
  6. Sallehuddin, N. A., Azizah Abdul Hamid, Salleh, S. Z., Nazia Abdul Majid, Hani Hafeeza Halim, Nurul Shazini Ramli, et al.
    MyJurnal
    In the present work, aqueous ethanolic (60% ethanol) extracts from selected Malaysian herbs
    including Murraya koenigii L. Spreng, Lawsonia inermis L., Cosmos caudatus Kunth, Piper
    betle L., and P. sarmentosum Roxb. were evaluated for their ergogenic, anti-diabetic and
    antioxidant potentials. Results showed that the analysed herbs had ergogenic property and
    were able to activate 5'AMP-activated protein kinase (AMPK) in a concentration dependant
    manner. The highest AMPK activation was exhibited by M. koenigii extract which showed no
    significant (p > 0.05) difference with green tea (positive control). For anti-diabetic potential,
    the highest α-glucosidase inhibition was exhibited by M. koenigii extract with IC50 of 43.35
    ± 7.5 µg/mL, which was higher than acarbose (positive control). The determinations of free
    radical scavenging activity and total phenolics content (TPC) indicated that the analysed herbs
    had good antioxidant activity. However, C. caudatus extract showed superior antioxidant
    activity with IC50 against free radical and TPC of 21.12 ± 3.20 µg/mL and 221.61 ± 7.49 mg
    GAE/g, respectively. RP-HPLC analysis established the presence of flavonoids in the herbs
    wherein L. inermis contained the highest flavonoid (catechin, epicatechin, naringin and rutin)
    content (668.87 mg/kg of extract). Correlations between the analyses were conducted, and
    revealed incoherent trends. Overall, M. koenigii was noted to be the most potent herb for
    enhancement of AMPK activity and α-glucosidase inhibition but exhibited moderate antioxidant activity. These results revealed that the selected herbs could be potential sources of
    natural ergogenic and anti-diabetic/antioxidant agents due to their rich profile of phenolics.
    Further analysis in vivo should be carried out to further elucidate the mechanism of actions of
    these herbs as ergogenic aids and anti-diabetic/antioxidant agents.
    Matched MeSH terms: Inhibitory Concentration 50
  7. Tan, H. M., Leong, K. H., Song, J., Mohd Sufian, N. S. F., Mohd Hazli, U. H. A., Chew, L. Y., et al.
    MyJurnal
    Strobilanthes crispus and Clinacanthus nutans are popular herbal plants in the Southeast
    Asian region. The present work was aimed at determining the antioxidant activities and the
    associated components in the leaf extracts of both species using polar and non-polar solvents
    namely water, methanol, ethyl acetate, and hexane. The total phenolic content (TPC) and total
    flavonoid content (TFC) were higher in the leaf extracts of S. crispus as compared to C.
    nutans. Among the solvents, methanol was the best solvent in extracting the antioxidant
    components for S. crispus (TPC: 159.85 ± 0.89 mg GAE/g extract and TFC: 955.47 ± 2.66 mg
    RE/g extract). However, for C. nutans, its methanolic extract yielded the highest TPC (36.39
    ± 0.17 mg GAE/g extract), whereas ethyl acetate yielded the highest TFC (229.61 ± 7.81 mg
    RE/g extract). The high levels of both TPC and TFC contributed to the antioxidant activities
    of S. crispus extract as reflected in the methanolic extract attaining the highest level of
    antioxidant activities, measured by ferric reducing antioxidant power (FRAP) (6.84 ± 1.12
    mmol Fe2+/g extract), DPPH radical scavenging (IC50: 203.60 ± 7.28 μg/mL), and Trolox
    equivalent antioxidant capacity (TEAC) (1.01 ± 0.01 mmol TE/g extract) assays. This
    contrasted with C. nutans which showed lower antioxidant activities owing to its lower TPC
    and TFC. Correlation analysis revealed significant correlations (p < 0.05, r = 0.915 - 0.985)
    between both TPC and TFC in S. crispus and antioxidant activities. However, only TPC of C.
    nutans showed a significant correlation with FRAP values (r = 0.934). Further tentative
    identification of the constituents in the extracts using HPLC-ESI-QToF-MS/MS revealed the
    existence of 20 polyphenolic compounds in both S. crispus and C. nutans, which were likely
    responsible for their antioxidant activities. In addition, 15 polyphenolic compounds classified
    as chalcones, isoflavanoids, flavones, and flavonols have not been previously reported in both
    species. The methanolic extracts of both species yielded a higher content of antioxidants, with
    S. crispus offering a richer source of dietary antioxidants as compared to C. nutans. However,
    further study is needed to identify their bioactivities in relation to their bioactive components.
    Matched MeSH terms: Inhibitory Concentration 50
  8. Tabassam, Q., Mehmood, T., Anwar, F., Saari, N., Qadir, R.
    MyJurnal
    The present work studies the profiling of phenolic bioactive and in vitro biological (anticancer, antioxidant, and antimicrobial) activities of different solvent extracts from Withania
    somnifera fruit. Anticancer activity was performed using potato-disc assay and Agrobacterium tumefaciens. While antibacterial and antifungal evaluation was done by using disc diffusion method against bacterial (Staphylococcus aureus, S. epidermidis, Escherichia coli, and
    Klebsiella pneumonia) and fungal (Aspergillus flavus and Fusarium oxysporum) strains.
    Among different extraction solvents used, n-hexane extract exhibited the highest inhibition of
    tumour initiation (64%), whereas ethyl acetate (15%) was the lowest by using potato-disc
    assay. Highest total phenolic and total flavonoid contents were noted for methanolic (69.10
    GAE mg/g DW%) and n-hexane (29.45 CE mg/g DW%) extracts, respectively. For antioxidant potential, 2,2,1-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging (IC50) and reducing power EC50 were noted to be superior (0.6 and 2.0 mg/mL, respectively) for n-hexane
    extract. All the tested extracts showed considerable antibacterial and antifungal activity with
    the highest growth inhibition zones for K. pneumoniae (31.70 mm) and A. flavus (27.09 mm)
    were shown by n-hexane extract. High Performance Liquid Chromatographic (HPLC) analysis of individual phenolics (gallic acid, 2,288.48 mg/kg) indicated the highest contents of these
    compounds in n-hexane extract, which might explain the potent biological activities of this
    extract. Our findings revealed that the bioactive present in the tested fruit had significant
    potential as anticancer, antibacterial, and antifungal agents. Further studies are needed to
    elucidate the mechanism of actions of isolated bioactive against specific diseases such as
    cancer, especially in the case of n-hexane fraction.
    Matched MeSH terms: Inhibitory Concentration 50
  9. Mohd Dom NS, Yahaya N, Adam Z, Nik Abd Rahman NMA, Hamid M
    PMID: 32831872 DOI: 10.1155/2020/6374632
    The present study aimed to evaluate the potential of standardized methanolic extracts from seven Ficus deltoidea varieties in inhibiting the formation of AGEs, protein oxidation, and their antioxidant effects. The antiglycation activity was analyzed based on the inhibition of AGEs, fructosamine, and thiol groups level followed by the inhibition of protein carbonyl formation. The antioxidant activity (DPPH radical scavenging activity and reducing power assay) and total phenolic contents were evaluated. After 28 days of induction, all varieties of Ficus deltoidea extracts significantly restrained the formation of fluorescence AGEs by 4.55-5.14 fold. The extracts also reduced the fructosamine levels by 47.0-86.5%, increased the thiol group levels by 64.3-83.7%, and inhibited the formation of protein carbonyl by 1.36-1.76 fold. DPPH radical scavenging activity showed an IC50 value of 66.81-288.04 μg/ml and reducing power activity depicted at 0.02-0.24 μg/ml. The extent of phenolic compounds present in the extracts ranged from 70.90 to 299.78 mg·GAE/g. Apart from that, correlation studies between the activities were observed. This study revealed that seven varieties of Ficus deltoidea have the potential to inhibit AGEs formation and possess antioxidant activity that might be attributed to the presence of phenolic compounds.
    Matched MeSH terms: Inhibitory Concentration 50
  10. Othman H, Rahman H, Mohan S, Aziz S, Marif H, Ford D, et al.
    PMID: 32922508 DOI: 10.1155/2020/8764096
    This study investigated the in vivo antileukemic activity of palladium nanoparticles (Pd@W.tea-NPs) mediated by white tea extract in a murine model. The cell viability effect of Pd@W.tea-NPs, "blank" Pd nanoparticles, and white tea extract alone was determined in murine leukemia WEHI-3B cells and normal mouse fibroblasts (3T3 cells). Apoptotic and cell cycle arrest effects of Pd@W.tea-NPs in WEHI-3B cells were evaluated. The effects of Pd@W.tea-NPs administered orally to leukemic mice at 50 and 100 mg/kg daily over 28 days were evaluated. Pd@W.tea-NPs reduced the viability of WHEI-3B cells with IC50 7.55 μg/ml at 72 h. Blank Pd nanoparticles and white tea extract alone had smaller effects on WHEI-3B viability and on normal fibroblasts. Pd@W.tea-NPs increased the proportion of Annexin V-positive WHEI-3B cells and induced G2/M cell cycle arrest. Leukemic cells in the spleen were reduced by Pd@W.tea-NPs with an increase in Bax/Bcl-2 and cytochrome-C protein and mRNA levels indicating the activation of the mitochondrial apoptotic pathway. These effects replicated the effects of ATRA and were not observed using blank Pd nanoparticles. Pd@W.tea-NPs afford therapeutic efficacy against leukemia likely to pivot on activation of the mitochondrial pathway of apoptotic signaling and hence appear attractive potential candidates for development as a novel anticancer agent.
    Matched MeSH terms: Inhibitory Concentration 50
  11. Chandradevan M, Simoh S, Mediani A, Ismail NH, Ismail IS, Abas F
    PMID: 32047522 DOI: 10.1155/2020/3238561
    This study aimed to determine the total phenolic content, DPPH scavenging, α-glucosidase, and nitric oxide (NO) inhibition of Gynura procumbens and Cleome gynandra extracts obtained with five different ethanolic concentrations. The findings showed that the 100% ethanolic extract of G. procumbens had the highest phenolic content and the lowest IC50 values for DPPH scavenging and NO inhibition activity compared to the properties of the other extracts. For C. gynandra, the 20% and 100% ethanolic extracts had comparably high total phenolic contents, and the latter possessed the lowest IC50 value in the NO inhibition assay. In addition, the 20% ethanolic extract of C. gynandra had the lowest IC50 value in the DPPH scavenging assay. However, none of the extracts from either herb had the ability to inhibit α-glucosidase enzyme. Pearson correlation analysis indicated a strong relationship between the phenolic content and DPPH scavenging activity in both herb extracts. A moderately strong relationship was also observed between the phenolic content and NO inhibition in G. procumbens extracts and not in C. gynandra extracts. The UHPLC-ESI-Orbitrap-MS revealed major phenolics from the groups of hydroxycinnamic acids, hydroxybenzoic acids, and flavonoid derivatives from both herbs, which could be the key contributors to their bioactivities. Among the identified metabolites, 24 metabolites were tentatively assigned for the first time from both species of studied herbs. These two herbs could be recommended as prospective natural products with valuable medicinal properties.
    Matched MeSH terms: Inhibitory Concentration 50
  12. Abuelizz HA, Iwana NANI, Ahmad R, Anouar EH, Marzouk M, Al-Salahi R
    BMC Chem, 2019 Dec;13(1):52.
    PMID: 31384800 DOI: 10.1186/s13065-019-0560-4
    Diabetes is an emerging metabolic disorder. α-Glucosidase inhibitors, such as acarbose, delay the hydrolysis of carbohydrates by interfering with the digestive enzymes. This action decreases the glucose absorption and the postprandial glucose level. We have synthesized 25 tricyclic 2-phenoxypyrido[3,2-e][1,2,4]triazolo[1,5-a]pyrimidin-5(4H)-ones hybrids and evaluated their α-glucosidase inhibitory activity. Compounds 6h and 6d have shown stronger activity than that of acarbose. Compound 6h exhibited the highest inhibition with an IC50 of 104.07 µM. Molecular modelling studies revealed that compound 6h inhibits α-glucosidase due to the formation of a stable ligand-α-glucosidase complex and extra hydrogen bond interactions, and directed in the binding site by Trp329.25 tricyclic 2-phenoxypyrido[3,2-e][1,2,4]triazolo[1,5-a]pyrimidin-5(4H)-ones hybrids have been synthesized and evaluated their α-glucosidase inhibitory activity. Compounds 6h have shown stronger activity than that of acarbose.
    Matched MeSH terms: Inhibitory Concentration 50
  13. Tahlan S, Ramasamy K, Lim SM, Shah SAA, Mani V, Narasimhan B
    BMC Chem, 2019 Dec;13(1):12.
    PMID: 31384761 DOI: 10.1186/s13065-019-0533-7
    Background: Dihydrofolate reductase (DHFR) is an important target for antimetabolite class of antimicrobials because it participates in purine synthesis. 2-mercaptobenzimidazole (2MBI) has similar structural features as purine nucleotides. Given that benzimidazole and similar heteroaromatics have been broadly examined for their anticancer potential, so, we hereby report the design, synthesis and biological studies (i.e. antimicrobial and anticancer studies) of 2MBI derivatives.

    Methodology: The antimicrobial activity of synthesized 2MBI derivatives were evaluated against Gram positive and Gram negative bacterial species as well as fungal species by tube dilution technique whereas their anticancer activity was assessed against human colorectal carcinoma cell line (HCT116) by Sulforhodamine B (SRB) assay. They were also structurally characterized by IR, NMR, MS and elemental analyses.

    Results discussion and conclusion: The antimicrobial activity findings revealed that compound N1 (MIC
    bs,st,
    ca
     = 1.27, 2.54, 1.27 µM), N8 (MIC
    ec
    = 1.43 µM), N22 (MIC
    kp,an
    = 2.60 µM), N23 and N25 (MIC
    sa
    = 2.65 µM) exhibited significant antimicrobial effects against tested strains, i.e. Gram-positive, Gram-negative (bacterial) and fungal strains. The anticancer screening results demonstrated that compounds N9, N18 (IC50 = 5.85, 4.53 µM) were the most potent compounds against cancer cell line (HCT116) even more than 5-FU, the standard drug (IC50 = 9.99 µM).

    Matched MeSH terms: Inhibitory Concentration 50
  14. Taha M, Uddin I, Gollapalli M, Almandil NB, Rahim F, Farooq RK, et al.
    BMC Chem, 2019 Dec;13(1):102.
    PMID: 31410413 DOI: 10.1186/s13065-019-0617-4
    We have synthesized new series of bisindole analogs (1-27), characterized by 1HNMR and HR-EI-MS and evaluated for their anti-leishmanial potential. All compounds showed outstanding inhibitory potential with IC50 values ranging from 0.7 ± 0.01 to 13.30 ± 0.50 µM respectively when compared with standard pentamidine with IC50 value of 7.20 ± 0.20 µM. All analogs showed greater potential than standard except 10, 19 and 23 when compared with standard. Structure activity relationship has been also established for all compounds. Molecular docking studies were carried out to understand the binding interaction of active molecules.
    Matched MeSH terms: Inhibitory Concentration 50
  15. Kandasamy M, Mak KK, Devadoss T, Thanikachalam PV, Sakirolla R, Choudhury H, et al.
    BMC Chem, 2019 Dec;13(1):117.
    PMID: 31572984 DOI: 10.1186/s13065-019-0633-4
    Background: The transcription factor Nuclear factor erythroid-2-related factor 2 (NRF2) and its principal repressive regulator, Kelch-like ECH-associated protein 1 (KEAP1), are perilous in the regulation of inflammation, as well as maintenance of homeostasis. Thus, NRF2 activation is involved in cytoprotection against many inflammatory disorders. N'-Nicotinoylquinoxaline-2-carbohdyrazide (NQC) was structurally designed by the combination of important pharmacophoric features of bioactive compounds reported in the literature.

    Methods: NQC was synthesised and characterised using spectroscopic techniques. The compound was tested for its anti-inflammatory effect using Lipopolysaccharide from Escherichia coli (LPSEc) induced inflammation in mouse macrophages (RAW 264.7 cells). The effect of NQC on inflammatory cytokines was measured using enzyme-linked immune sorbent assay (ELISA). The Nrf2 activity of the compound NQC was determined using 'Keap1:Nrf2 Inhibitor Screening Assay Kit'. To obtain the insights on NQC's activity on Nrf2, molecular docking studies were performed using Schrödinger suite. The metabolic stability of NQC was determined using mouse, rat and human microsomes.

    Results: NQC was found to be non-toxic at the dose of 50 µM on RAW 264.7 cells. NQC showed potent anti-inflammatory effect in an in vitro model of LPSEc stimulated murine macrophages (RAW 264.7 cells) with an IC50 value 26.13 ± 1.17 µM. NQC dose-dependently down-regulated the pro-inflammatory cytokines [interleukin (IL)-1β (13.27 ± 2.37 μM), IL-6 (10.13 ± 0.58 μM) and tumor necrosis factor (TNF)-α] (14.41 ± 1.83 μM); and inflammatory mediator, prostaglandin E2 (PGE2) with IC50 values, 15.23 ± 0.91 µM. Molecular docking studies confirmed the favourable binding of NQC at Kelch domain of Keap-1. It disrupts the Nrf2 interaction with kelch domain of keap 1 and its IC50 value was 4.21 ± 0.89 µM. The metabolic stability studies of NQC in human, rat and mouse liver microsomes revealed that it is quite stable with half-life values; 63.30 ± 1.73, 52.23 ± 0.81, 24.55 ± 1.13 min; microsomal intrinsic clearance values; 1.14 ± 0.31, 1.39 ± 0.87 and 2.96 ± 0.34 µL/min/g liver; respectively. It is observed that rat has comparable metabolic profile with human, thus, rat could be used as an in vivo model for prediction of pharmacokinetics and metabolism profiles of NQC in human.

    Conclusion: NQC is a new class of NRF2 activator with potent in vitro anti-inflammatory activity and good metabolic stability.

    Matched MeSH terms: Inhibitory Concentration 50
  16. Al-Refai M, Ibrahim MM, Azmi MN, Osman H, Bakar MHA, Geyer A
    Molecules, 2019 Nov 10;24(22).
    PMID: 31717690 DOI: 10.3390/molecules24224072
    A series of 2-methoxypyridine-3-carbonitrile (5a-i)-bearing aryl substituents were successfully synthesized in good yields by the condensation of chalcones (4a-i) with malononitrile in basic medium. The condensation process, in most cases, offers a route to a variety of methoxypyridine derivatives (6a-g) as side products in poor yields. All new compounds were fully characterized using different spectroscopic methods. Mass ESI-HMRS measurements were also performed. Furthermore, these compounds were screened for their in vitro cytotoxicity activities against three cancer cell lines; namely, those of the liver (line HepG2), prostate (line DU145) and breast (line MBA-MB-231). The cytotoxicity assessment revealed that compounds 5d, 5g, 5h and 5i exhibit promising antiproliferative effects (IC50 1-5 µM) against those three cancer cell lines.
    Matched MeSH terms: Inhibitory Concentration 50
  17. Ravishankar D, Albadawi DAI, Chaggar V, Patra PH, Williams HF, Salamah M, et al.
    Eur J Pharmacol, 2019 Nov 05;862:172627.
    PMID: 31461638 DOI: 10.1016/j.ejphar.2019.172627
    Isorhapontigenin is a polyphenolic compound found in Chinese herbs and grapes. It is a methoxylated analogue of a stilbenoid, resveratrol, which is well-known for its various beneficial effects including anti-platelet activity. Isorhapontigenin possesses greater oral bioavailability than resveratrol and has also been identified to possess anti-cancer and anti-inflammatory properties. However, its effects on platelet function have not been reported previously. In this study, we report the effects of isorhapontigenin on the modulation of platelet function. Isorhapontigenin was found to selectively inhibit ADP-induced platelet aggregation with an IC50 of 1.85 μM although it displayed marginal inhibition on platelet aggregation induced by other platelet agonists at 100 μM. However, resveratrol exhibited weaker inhibition on ADP-induced platelet aggregation (IC50 > 100 μM) but inhibited collagen induced platelet aggregation at 50 μM and 100 μM. Isorhapontigenin also inhibited integrin αIIbβ3 mediated inside-out and outside-in signalling and dense granule secretion in ADP-induced platelet activation but interestingly, no effect was observed on α-granule secretion. Isorhapontigenin did not exert any cytotoxicity on platelets at the concentrations of up to 100 μM. Furthermore, it did not affect haemostasis in mice at the IC50 concentration (1.85 μM). In addition, the mechanistic studies demonstrated that isorhapontigenin increased cAMP levels and VASP phosphorylation at Ser157 and decreased Akt phosphorylation. This suggests that isorhapontigenin may interfere with cAMP and PI3K signalling pathways that are associated with the P2Y12 receptor. Molecular docking studies emphasised that isorhapontigenin has greater binding affinity to P2Y12 receptor than resveratrol. Our results demonstrate that isorhapontigenin has selective inhibitory effects on ADP-stimulated platelet activation possibly via P2Y12 receptor.
    Matched MeSH terms: Inhibitory Concentration 50
  18. Zaman K, Rahim F, Taha M, Wadood A, Shah SAA, Ahmed QU, et al.
    Sci Rep, 2019 11 05;9(1):16015.
    PMID: 31690793 DOI: 10.1038/s41598-019-52100-0
    Here in this study regarding the over expression of TP, which causes some physical, mental and socio problems like psoriasis, chronic inflammatory disease, tumor angiogenesis and rheumatoid arthritis etc. By this consideration, the inhibition of this enzyme is vital to secure life from serious threats. In connection with this, we have synthesized twenty derivatives of isoquinoline bearing oxadiazole (1-20), characterized through different spectroscopic techniques such as HREI-MS, 1H- NMR and 13C-NMR and evaluated for thymidine phosphorylase inhibition. All analogues showed outstanding inhibitory potential ranging in between 1.10 ± 0.05 to 54.60 ± 1.50 µM. 7-Deazaxanthine (IC50 = 38.68 ± 1.12 µM) was used as a positive control. Through limited structure activity relationships study, it has been observed that the difference in inhibitory activities of screened analogs are mainly affected by different substitutions on phenyl ring. The effective binding interactions of the most active analogs were confirmed through docking study.
    Matched MeSH terms: Inhibitory Concentration 50
  19. Shehzad MT, Hameed A, Al-Rashida M, Imran A, Uroos M, Asari A, et al.
    Bioorg Chem, 2019 11;92:103244.
    PMID: 31541804 DOI: 10.1016/j.bioorg.2019.103244
    The role of aldose reductase (ALR2) in diabetes mellitus is well-established. Our interest in finding ALR2 inhibitors led us to explore the inhibitory potential of new thiosemicarbazones. In this study, we have synthesized adamantyl-thiosemicarbazones and screened them as aldehyde reductase (ALR1) and aldose reductase (ALR2) inhibitors. The compounds bearing phenyl 3a, 2-methylphenyl 3g and 2,6-dimethylphenyl 3m have been identified as most potent ALR2 inhibitors with IC50 values of 3.99 ± 0.38, 3.55 ± 0.26 and 1.37 ± 0.92 µM, respectively, compared with sorbinil (IC50 = 3.14 ± 0.02 μM). The compounds 3a, 3g, and 3m also inhibit ALR1 with IC50 value of 7.75 ± 0.28, 7.26 ± 0.39 and 7.04 ± 2.23 µM, respectively. Molecular docking was also performed for putative binding of potent inhibitors with target enzyme ALR2. The most potent 2,6-dimethylphenyl bearing thiosemicarbazone 3m (IC50 = 1.37 ± 0.92 µM for ALR2) and other two compound 3a and 3g could potentially lead for the development of new therapeutic agents.
    Matched MeSH terms: Inhibitory Concentration 50
  20. Taha M, Alshamrani FJ, Rahim F, Hayat S, Ullah H, Zaman K, et al.
    Molecules, 2019 Oct 23;24(21).
    PMID: 31652777 DOI: 10.3390/molecules24213819
    A new class of triazinoindole-bearing thiosemicarbazides (1-25) was synthesized and evaluated for α-glucosidase inhibitory potential. All synthesized analogs exhibited excellent inhibitory potential, with IC50 values ranging from 1.30 ± 0.01 to 35.80 ± 0.80 µM when compared to standard acarbose (an IC50 value of 38.60 ± 0.20 µM). Among the series, analogs 1 and 23 were found to be the most potent, with IC50 values of 1.30 ± 0.05 and 1.30 ± 0.01 µM, respectively. The structure-activity relationship (SAR) was mainly based upon bringing about different substituents on the phenyl rings. To confirm the binding interactions, a molecular docking study was performed.
    Matched MeSH terms: Inhibitory Concentration 50
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