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  1. Ng HL, Sellappans R, Loo JSE
    Int J Pharm Pract, 2023 Sep 30;31(5):489-495.
    PMID: 37526297 DOI: 10.1093/ijpp/riad042
    OBJECTIVES: To determine the adoption and perception of mobile health (mHealth) applications among community pharmacists in Malaysia.

    METHODS: A cross-sectional survey using a self-administered questionnaire was conducted with 300 community pharmacists in the Klang Valley, Malaysia using a stratified sampling approach. The questionnaire consisted of 36 questions with three sections: demographic data, adoption of mHealth applications and perception towards mHealth applications. Descriptive and inferential tests as well as exploratory factor analysis were used to analyse the data.

    KEY FINDINGS: Adoption of mHealth applications by community pharmacists for both professional and personal use was relatively high at 79.7%. Utilised mHealth applications were primarily from the medical references category, while applications for patient monitoring, personal care and fitness were used to a lesser degree. Among mHealth application users, only 65.7% recommended them to their patients. Overall perception towards mHealth applications was positive, but perception towards the benefits and favour of mHealth applications for their patients was lower. This was corroborated by the factor analysis, which identified four main factors explaining 59.9% of variance in the dataset. These factors were perception towards use in their own professional practice, perception on benefits and use in their patients, perception on specific features of mHealth applications, and reliability of mHealth applications.

    CONCLUSIONS: Adoption of mHealth applications among community pharmacists in Malaysia is high. Community pharmacists are more likely to use mHealth applications professionally and personally but less likely to recommend them to patients due to less favourable perceptions on how patients will benefit from mHealth applications.

  2. Yau MQ, Emtage AL, Loo JSE
    J Comput Aided Mol Des, 2020 Nov;34(11):1133-1145.
    PMID: 32851579 DOI: 10.1007/s10822-020-00339-5
    Recent breakthroughs in G protein-coupled receptor (GPCR) crystallography and the subsequent increase in number of solved GPCR structures has allowed for the unprecedented opportunity to utilize their experimental structures for structure-based drug discovery applications. As virtual screening represents one of the primary computational methods used for the discovery of novel leads, the GPCR-Bench dataset was created to facilitate comparison among various virtual screening protocols. In this study, we have benchmarked the performance of Molecular Mechanics/Poisson-Boltzmann Surface Area (MM/PBSA) in improving virtual screening enrichment in comparison to docking with Glide, using the entire GPCR-Bench dataset of 24 GPCR targets and 254,646 actives and decoys. Reranking the top 10% of the docked dataset using MM/PBSA resulted in improvements for six targets at EF1% and nine targets at EF5%, with the gains in enrichment being more pronounced at the EF1% level. We additionally assessed the utility of rescoring the top ten poses from docking and the ability of short MD simulations to refine the binding poses prior to MM/PBSA calculations. There was no clear trend of the benefit observed in both cases, suggesting that utilizing a single energy minimized structure for MM/PBSA calculations may be the most computationally efficient approach in virtual screening. Overall, the performance of MM/PBSA rescoring in improving virtual screening enrichment obtained from docking of the GPCR-Bench dataset was found to be relatively modest and target-specific, highlighting the need for validation of MM/PBSA-based protocols prior to prospective use.
  3. Loo JSE, Yong AYY, Yong YN
    Chem Biol Drug Des, 2020 11;96(5):1244-1254.
    PMID: 32462752 DOI: 10.1111/cbdd.13733
    Both the inactive- and active-state CB1 receptor crystal structures have now been solved, allowing their application in various structure-based drug design methods. One potential method utilizing these crystal structures is the Molecular Mechanics/Poisson-Boltzmann Surface Area (MM/PBSA) method of predicting relative binding free.
  4. Francis J, Toh LS, Sellappans R, Loo JSE
    Int J Clin Pharm, 2021 Jun;43(3):604-612.
    PMID: 33507463 DOI: 10.1007/s11096-020-01169-z
    Background The incidence of osteoporosis in Malaysia is increasing due to a fast-ageing population. Because of its silent nature, various osteoporosis risk assessment tools exist to detect high-risk patients and facilitate referrals for bone mineral density measurements. As an accessible point of contact, community pharmacists would benefit from the utilization of these tools and familiarity with guideline recommendations for osteoporosis screening. Aim This study aimed to investigate the awareness of osteoporosis risk assessment tools, practice behaviour towards osteoporosis, and knowledge of guideline recommendations among community pharmacists in the Klang Valley, Malaysia. Setting Community pharmacies. Methods This study was a cross-sectional study which sampled 284 community pharmacists practicing in the Klang Valley, using a stratified sampling approach. The study was conducted using a self-administered questionnaire which was divided into three sections: demographic data, knowledge of osteoporosis risk assessment tools and guideline recommendations, and practice behaviour towards osteoporosis. Practice behaviour was assessed with 15 items using a 5-point Likert scale. Main outcome measure. Proportion of respondents aware of osteoporosis risk assessment tools and respondent knowledge on guideline recommendations for osteoporosis screening. Results A total of 284 community pharmacists participated in the study. 84.1% of the respondents were aware of at least one risk assessment tool. However, only a small proportion of pharmacists (14.9%) regularly used these tools in their practice. Respondents perceived these tools to be relevant and beneficial, but perception towards their accessibility, ease-of-use, and administration time was mixed, suggesting unfamiliarity. Respondents preferred to conduct clinical assessments based on risk factors, with respondents identifying a mean of 10.1 ± 3.4 out of 15 risk factors. However, several clinically relevant risk factors were frequently unidentified. Knowledge of guideline recommendations among respondents was low. Conclusion There is some awareness of osteoporosis risk assessment tools but use in practice remains low among community pharmacists in Malaysia. There is potential to increase the use of these tools and knowledge of recommendations for osteoporosis screening and referral among community pharmacists.
  5. Loo JSE, Lim SW, Ng YK, Tiong JJL
    Int J Pharm Pract, 2017 Dec;25(6):429-437.
    PMID: 28211115 DOI: 10.1111/ijpp.12352
    OBJECTIVES: To identify factors influencing the decisions of Malaysian first-year pharmacy undergraduate students in private higher education when choosing to pursue a degree in pharmacy as well as their choice of private university.

    METHODS: This cross-sectional study employed a validated, self-administered questionnaire which was administered to 543 first-year pharmacy students from nine different private universities. Factor analysis was utilised to extract key factors from the responses. Descriptive and inferential statistics were used to analyse the data.

    KEY FINDINGS: Eight factors motivating students' decision to study pharmacy emerged from the responses, accounting for 63.8% of the variance observed. Students were primarily motivated by intrinsic interests, with work conditions and profession attributes also exerting significant influence. In terms of choice of private university, nine factors were identified, accounting for 73.8% of the variance observed. The image of the school and university were most influential factors in this context, followed by university safety, programme attributes and financial factors.

    CONCLUSIONS: First-year pharmacy students in the private higher education sector are motivated by intrinsic interest when choosing to study pharmacy over other courses, while their choice of private university is influenced primarily by the image of the school and university.

  6. Foong RTK, Sellappans R, Loo JSE
    J Eval Clin Pract, 2020 Feb;26(1):165-171.
    PMID: 31168913 DOI: 10.1111/jep.13180
    BACKGROUND: Potentially inappropriate medications (PIMs) in older adults are detrimental to both clinical outcomes and health care costs, with their prominence set to increase in tandem with a fast-growing ageing population. Beers Criteria is one of the most commonly used guidelines that lists specific PIMs. Community pharmacists would therefore benefit from knowledge of Beers Criteria in detecting PIMs in primary care. This study therefore investigates the awareness of Beers Criteria and knowledge of PIMs among community pharmacists in the Klang Valley, Malaysia.

    METHODS: The study was conducted using a self-administered questionnaire. Knowledge of PIMs was assessed using 10 clinical vignettes based on the 2015 Beers Criteria. Practice behaviour towards older customers was assessed using 10 items with a 5-point Likert scale. Descriptive and inferential statistics were used to analyse the data.

    RESULTS: A total of 277 community pharmacists participated in the study. Only 27.1% of the pharmacists were aware of Beers Criteria, and of these, only 37.3% were aware of the latest 2015 update. The respondents demonstrated moderate knowledge of PIMs with a mean total score of 5.46 ± 1.89 out of a maximum of 10. Pharmacists who were aware of Beers Criteria had significantly higher scores (6.31 vs 5.14, P 

  7. Su WS, Thum CM, Loo JSE
    Int J Pharm Pract, 2022 Jan 07;30(1):59-66.
    PMID: 34962576 DOI: 10.1093/ijpp/riab075
    OBJECTIVES: To determine the prescribing patterns and identify potentially inappropriate prescribing practices among general practitioners in the private primary care sector by analysing a large electronic health insurance claims database.

    METHODS: Medical claims records from February 2019 to February 2020 were extracted from a health insurance claims database. Data cleaning and data analysis were performed using Python 3.7 with the Pandas, NumPy and Matplotlib libraries. The top five most common diagnoses were identified, and for each diagnosis, the most common medication classes and medications prescribed were quantified. Potentially inappropriate prescribing practices were identified by comparing the medications prescribed with relevant clinical guidelines.

    KEY FINDINGS: The five most common diagnoses were upper respiratory tract infection (41.5%), diarrhoea (7.7%), musculoskeletal pain (7.6%), headache (6.7%) and gastritis (4.0%). Medications prescribed by general practitioners were largely as expected for symptomatic management of the respective conditions. One area of potentially inappropriate prescribing identified was inappropriate antibiotic choice. Same-class polypharmacy that may lead to an increased risk of adverse events were also identified, primarily involving multiple paracetamol-containing products, non-steroidal anti-inflammatory drugs (NSAIDs), and antihistamines. Other areas of non-adherence to guidelines identified included the potential overuse of oral corticosteroids and oral salbutamol, and inappropriate gastroprotection for patients receiving NSAIDs.

    CONCLUSIONS: While prescribing practices are generally appropriate within the private primary care sector, there remain several areas where some potentially inappropriate prescribing occurs. The areas identified should be the focus in continuing efforts to improve prescribing practices to obtain the optimal clinical outcomes while reducing unnecessary risks and healthcare costs.

  8. Yau MQ, Liew CWY, Toh JH, Loo JSE
    J Mol Model, 2024 Oct 31;30(11):390.
    PMID: 39480515 DOI: 10.1007/s00894-024-06189-4
    CONTEXT: The substantial increase in the number of active and inactive-state CB1 receptor experimental structures has provided opportunities for CB1 drug discovery using various structure-based drug design methods, including the popular end-point methods for predicting binding free energies-Molecular Mechanics/Poisson-Boltzmann Surface Area (MM/PBSA) and Molecular Mechanics/Generalized Born Surface Area (MM/GBSA). In this study, we have therefore evaluated the performance of MM/PBSA and MM/GBSA in calculating binding free energies for CB1 receptor. Additionally, with both MM/PBSA and MM/GBSA being known for their highly individualized performance, we have evaluated the effects of various simulation parameters including the use of energy minimized structures, choice of solute dielectric constant, inclusion of entropy, and the effects of the five GB models. Generally, MM/GBSA provided higher correlations than MM/PBSA (rMM/GBSA = 0.433 - 0.652 vs. rMM/PBSA = 0.100 - 0.486) regardless of the simulation parameters, while also offering faster calculations. Improved correlations were observed with the use of molecular dynamics ensembles compared with energy minimized structures and larger solute dielectric constants. Incorporation of entropic terms led to unfavorable results for both MM/PBSA and MM/GBSA for a majority of the dataset, while the evaluation of the various GB models exerted a varying effect on both the datasets. The findings obtained in this study demonstrate the utility of MM/PBSA and MM/GBSA in predicting binding free energies for the CB1 receptor, hence providing a useful benchmark for their applicability in the endocannabinoid system as well as other G protein-coupled receptors.

    METHODS: The study utilized the docked dataset (Induced Fit Docking with Glide XP scoring function) from Loo et al., consisting of 46 ligands-23 agonists and 23 antagonists. The equilibrated structures from Loo et al. were subjected to 30 ns production simulations using GROMACS 2018 at 300 K and 1 atm with the velocity rescaling thermostat and the Parinello-Rahman barostat. AMBER ff99SB*-ILDN was used for the proteins, General Amber Force Field (GAFF) was used for the ligands, and Slipids parameters were used for lipids. MM/PBSA and MM/GBSA binding free energies were then calculated using gmx_MMPBSA. The solute dielectric constant was varied between 1, 2, and 4 to study the effect of different solute dielectric constants on the performance of MM/PB(GB)SA. The effect of entropy on MM/PB(GB)SA binding free energies was evaluated using the interaction entropy module implemented in gmx_MMPBSA. Five GB models, GBHCT, GBOBC1, GBOBC2, GBNeck, and GBNeck2, were evaluated to study the effect of the choice of GB models in the performance of MM/GBSA. Pearson correlation coefficients were used to measure the correlation between experimental and predicted binding free energies.

  9. Yau MQ, Emtage AL, Chan NJY, Doughty SW, Loo JSE
    J Comput Aided Mol Des, 2019 05;33(5):487-496.
    PMID: 30989574 DOI: 10.1007/s10822-019-00201-3
    The recent expansion of GPCR crystal structures provides the opportunity to assess the performance of structure-based drug design methods for the GPCR superfamily. Molecular Mechanics/Poisson-Boltzmann Surface Area (MM/PBSA)-based methods are commonly used for binding affinity prediction, as they provide an intermediate compromise of speed and accuracy between the empirical scoring functions used in docking and more robust free energy perturbation methods. In this study, we systematically assessed the performance of MM/PBSA in predicting experimental binding free energies using twenty Class A GPCR crystal structures and 934 known ligands. Correlations between predicted and experimental binding free energies varied significantly between individual targets, ranging from r = - 0.334 in the inactive-state CB1 cannabinoid receptor to r = 0.781 in the active-state CB1 cannabinoid receptor, while average correlation across all twenty targets was relatively poor (r = 0.183). MM/PBSA provided better predictions of binding free energies compared to docking scores in eight out of the twenty GPCR targets while performing worse for four targets. MM/PBSA binding affinity predictions calculated using a single, energy minimized structure provided comparable predictions to sampling from molecular dynamics simulations and may be more efficient when computational cost becomes restrictive. Additionally, we observed that restricting MM/PBSA calculations to ligands with a high degree of structural similarity to the crystal structure ligands improved performance in several cases. In conclusion, while MM/PBSA remains a valuable tool for GPCR structure-based drug design, its performance in predicting the binding free energies of GPCR ligands remains highly system-specific as demonstrated in a subset of twenty Class A GPCRs, and validation of MM/PBSA-based methods for each individual case is recommended before prospective use.
  10. Loo JSE, Emtage AL, Ng KW, Yong ASJ, Doughty SW
    J Mol Graph Model, 2017 Dec 29;80:38-47.
    PMID: 29306746 DOI: 10.1016/j.jmgm.2017.12.017
    GPCR crystal structures have become more readily accessible in recent years. However, homology models of GPCRs continue to play an important role as many GPCR structures remain unsolved. The new crystal structures now available provide not only additional templates for homology modelling but also the opportunity to assess the performance of homology models against their respective crystal structures and gain insight into the performance of such models. In this study we have constructed homology models from templates of various transmembrane sequence identities for eight GPCR targets to better understand the relationship between transmembrane sequence identity and model quality. Model quality was assessed relative to the crystal structure in terms of structural accuracy as well as performance in two typical structure-based drug design applications: ligand binding pose prediction and docking enrichment in virtual screening. Crystal structures significantly outperformed homology models in both assessments. Accurate ligand binding pose prediction was possible but difficult to achieve using homology models, even with the use of induced fit docking. In virtual screening using homology models still conferred significant enrichment compared to random selection, with a clear benefit also observed in using models optimized through induced fit docking. Our results indicate that while homology models that are reasonably accurate structurally can be constructed, without significant refinement homology models will be outperformed by crystal structures in ligand binding pose prediction and docking enrichment regardless of the template used, primarily due to the extremely high level of structural accuracy needed for such applications.
  11. Lim SYM, Loo JSE, Alshagga M, Alshawsh MA, Ong CE, Pan Y
    Toxicol Rep, 2022;9:759-768.
    PMID: 36518400 DOI: 10.1016/j.toxrep.2022.03.040
    Cathinone is the psychostimulatory major active ingredient of khat (Catha edulis Forsk) and are often co-abused with alcohols and polydrugs. With the increased consumption of khat and cathinones on a global scale, efforts should be channelled into understanding and minimising the excruciating effects of possible khat-drug interactions. This study aimed to determine the in vitro inhibitory effects of cathinone on CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2E1, CYP2J2 and CYP3A5 and the in silico identification of their type of interactions and residues involved. The activities of CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2E1, CYP2J2 and CYP3A5 were examined by fluorescence based assays using recombinant cDNA-expressed human CYPs in Vivid® P450 screening kits. Cathinone reversibly inhibited CYP1A2, CYP2A6 and CYP3A5 via competitive, uncompetitive and noncompetitive modes with inhibition constant (Ki) values of 57.12, 13.75 and 23.57 µM respectively. Cathinone showed negligible inhibitory effects on CYP2B6, CYP2C8, CYP2C19, CYP2E1 and CYP2J2. Cathinone showed negligible time dependent inhibition on all 8 CYPs. Docking studies was performed on cathinone with CYP1A2, CYP2A6 and CYP3A5 following their inhibition in vitro. Cathinone is bound to a few key amino acid residues in the active sites while π-π interactions are formed in aromatic clusters of CYP1A2 and CYP3A5. These findings offer valuable reference for the use of cathinones and khat when combined with therapeutic drugs that are metabolised by CYP enzymes especially patients on medications metabolised by CYP1A2, CYP2A6 and CYP3A5.
  12. Yau MQ, Wan AJ, Tiong ASH, Yiap YS, Loo JSE
    Chem Biol Drug Des, 2024 Jul;104(1):e14591.
    PMID: 39010276 DOI: 10.1111/cbdd.14591
    Computational target fishing plays an important role in target identification, particularly in drug discovery campaigns utilizing phenotypic screening. Numerous approaches exist to predict potential targets for a given ligand, but true targets may be inconsistently ranked. More advanced simulation methods may provide benefit in such cases by reranking these initial predictions. We evaluated the ability of binding pose metadynamics to improve the predicted rankings for three diverse ligands and their six true targets. Initial predictions using pharmacophore mapping showed no true targets ranked in the top 50 and two targets each ranked within the 50-100, 100-150, and 250-300 ranges respectively. Following binding pose metadynamics, ranking of true targets improved for four out of the six targets and included the highest ranked predictions overall, while rankings deteriorated for two targets. The revised rankings predicted two true targets ranked within the top 50, and one target each within the 50-100, 100-150, 150-200, and 200-250 ranges respectively. The findings of this study demonstrate that binding pose metadynamics may be of benefit in refining initial predictions from structure-based target fishing algorithms, thereby improving the efficiency of the target identification process in drug discovery efforts.
  13. Lee ZY, Loo JSE, Wibowo A, Mohammat MF, Foo JB
    Carbohydr Res, 2021 Oct;508:108395.
    PMID: 34280804 DOI: 10.1016/j.carres.2021.108395
    Dysregulation of glycosylation pathways has been well documented in several types of cancer, where it often participates in cancer development and progression, especially cancer metastasis. Hence, inhibition of glycosidases such as mannosidases can disrupt the biosynthesis of glycans on cell surface glycoproteins and modify their role in carcinogenesis and metastasis. Several reviews have delineated the role of N-glycosylation in cancer, but the data regarding effective inhibitors remains sparse. Golgi α-mannosidase has been an attractive therapeutic target for preventing the formation of ß1,6-branched complex type N-glycans. However, due to its high structural similarity to the broadly specific lysosomal α-mannosidase, undesired co-inhibition occurs and this leads to serious side effects that complicates its potential role as a therapeutic agent. Even though extensive efforts have been geared towards the discovery of effective inhibitors, no breakthrough has been achieved thus far which could allow for their use in clinical settings. Improving the specificity of current inhibitors towards Golgi α-mannosidase is requisite in progressing this class of compounds in cancer chemotherapy. In this review, we highlight a few potent and selective inhibitors discovered up to the present to guide researchers for rational design of further effective inhibitors to overcome the issue of specificity.
  14. Lim SYM, Loo JSE, Alshagga M, Alshawsh MA, Ong CE, Pan Y
    Int J Toxicol, 2022;41(5):355-366.
    PMID: 35658727 DOI: 10.1177/10915818221103790
    Cathine is the stable form of cathinone, the major active compound found in khat (Catha edulis Forsk) plant. Khat was found to inhibit major phase I drug metabolizing cytochrome P450 (CYP) enzyme activities in vitro and in vivo. With the upsurge of khat consumption and the potential use of cathine to combat obesity, efforts should be channelled into understanding potential cathine-drug interactions, which have been rather limited. The present study aimed to assess CYPs activity and inhibition by cathine in a high-throughput in vitro fluorescence-based enzyme assay and molecular docking analysis to identify how cathine interacts within various CYPs' active sites. The half maximal inhibitory concentration (IC50) values of cathine determined for CYP2A6 and CYP3A4 were 80 and 90 μM, while CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP2J2 and CYP3A5 showed no significant inhibition. Furthermore, in Ki analysis, the Lineweaver-Burk plots depicted non-competitive mixed inhibition of cathine on both CYP2A6 and CYP3A4 with Ki value of 63 and 100 μM, respectively. Cathine showed negligible time-dependent inhibition on CYPs. Further, molecular docking studies showed that cathine was bound to CYP2A6 via hydrophobic, hydrogen and π-stacking interactions and formed hydrophobic and hydrogen bonds with active site residues in CYP3A4. Both molecular docking prediction and in vitro outcome are in agreement, granting more detailed insights for predicting CYPs metabolism besides the possible cathine-drug interactions. Cathine-drug interactions may occur with concomitant consumption of khat or cathine-containing products with medications metabolized by CYP2A6 and CYP3A4.
  15. Ahmad B, Friar EP, Taylor E, Vohra MS, Serpell CJ, Garrett MD, et al.
    Eur J Pharmacol, 2023 Jan 05;938:175445.
    PMID: 36473593 DOI: 10.1016/j.ejphar.2022.175445
    In this study, the anti-obesity effects of 5,7,3',4',5-pentamethoxyflavone (PMF) and 6,2',4'-trimethoxyflavone (TMF) were evaluated through two distinct mechanisms of action: inhibition of crude porcine pancreatic lipase (PL), and inhibition of adipogenesis in 3T3-L1 pre-adipocytes. Both flavones show dose dependent, competitive inhibition of PL activity. Molecular docking studies revealed binding of the flavones to the active site of PL. In 3T3-L1 adipocytes, both flavones reduced the accumulation of lipids and triglycerides. PMF and TMF also lowered the expression of adipogenic and lipogenic genes. They both reduced the expression of peroxisome proliferator-activated receptor-gamma (PPAR-γ), CCAAT/enhancer-binding protein α and β (C/EBP α and β), sterol regulatory element-binding protein 1 (SREBF 1), fatty acid synthase (FASN), adipocyte binding protein 2 (aP2), and leptin gene. In addition, these flavones enhanced adiponectin mRNA expression, increased lipolysis and enhanced the expression of lipolytic genes: adipose triglycerides lipase (ATGL), hormone sensitive lipase (HSL) and monoglycerides lipase (MAGL) in mature 3T3-L1 adipocytes. Overall, PMF was seen to be a more potent inhibitor of both PL activity and adipogenesis versus TMF. These results suggest that PMF and TMF possess anti-obesity activities and can be further evaluated for their anti-obesity effects.
  16. Al-Khdhairawi AAQ, Loo JSE, Abd Mutalib N, Abd Latip N, Manshoor N, Abu Bakar H, et al.
    Phytochemistry, 2023 Jul;211:113685.
    PMID: 37088350 DOI: 10.1016/j.phytochem.2023.113685
    Four previously undescribed alkaloids, aspergillinine A-D, and four known diterpene pyrones were isolated from the potato dextrose agar (PDA) culture of Aspergillus sp. HAB10R12. The chemical structures of the isolated compounds were elucidated based on a detailed analysis of their NMR and MS data. The absolute configuration of the isolated compounds was determined by Electronic Circular Dichroism analysis coupled with computational methods. Aspergillinine A represents the first example of a diketopiperazine dipeptide containing the unnatural amino acid N-methyl kynurenine. Its absolute configuration revealed that it adopts a rather unusual conformation. Aspergillinine B represents a previously unencountered skeleton containing an isoindolinone ring. Aspergillinine C and D were similar to previously isolated diketopiperazine alkaloids, namely, lumpidin and brevianamide F, respectively. The diterpene pyrones were isolated twice previously, once from a soil-derived Aspergillus species, and once from the liquid culture of Aspergillus sp. HAB10R12. The alkaloids isolated in this study showed no antiproliferative activity when tested against HepG2 and A549 cancer cell lines.
  17. Ahmad B, Friar EP, Vohra MS, Khan N, Serpell CJ, Garrett MD, et al.
    Chem Biol Interact, 2023 Jul 01;379:110503.
    PMID: 37084996 DOI: 10.1016/j.cbi.2023.110503
    Hydroxylated polymethoxyflavones (HPMFs) have been shown to possess various anti-disease effects, including against obesity. This study investigates the anti-obesity effects of HPMFs in further detail, aiming to gain understanding of their mechanism of action in this context. The current study demonstrates that two HPMFs; 3'-hydroxy-5,7,4',5'-tetramethoxyflavone (3'OH-TetMF) and 4'-hydroxy-5,7,3',5'-tetramethoxyflavone (4'OH-TetMF) possess anti-obesity effects. They both significantly reduced pancreatic lipase activity in a competitive manner as demonstrated by molecular docking and kinetic studies. In cell studies, it was revealed that both of the HPMFs suppress differentiation of 3T3-L1 mouse embryonic fibroblast cells during the early stages of adipogenesis. They also reduced expression of key adipogenic and lipogenic marker genes, namely peroxisome proliferator-activated receptor-gamma (PPARγ), CCAAT/enhancer-binding protein α and β (C/EBP α and β), adipocyte binding protein 2 (aP2), fatty acid synthase (FASN), and sterol regulatory element-binding protein 1 (SREBF 1). They also enhanced the expression of cell cycle genes, i.e., cyclin D1 (CCND1) and C-Myc, and reduced cyclin A2 expression. When further investigated, it was also observed that these HPMFs accelerate lipid breakdown (lipolysis) and enhance lipolytic genes expression. Moreover, they also reduced the secretion of proteins (adipokines), including pro-inflammatory cytokines, from mature adipocytes. Taken together, this study concludes that these HPMFs have anti-obesity effects, which are worthy of further investigation.
  18. Lee ZY, Lee WH, Lim JS, Ali AAA, Loo JSE, Wibowo A, et al.
    Life Sci, 2024 Sep 01;352:122868.
    PMID: 38936604 DOI: 10.1016/j.lfs.2024.122868
    Membrane trafficking within the Golgi apparatus plays a pivotal role in the intracellular transportation of lipids and proteins. Dysregulation of this process can give rise to various pathological manifestations, including cancer. Exploiting Golgi defects, cancer cells capitalise on aberrant membrane trafficking to facilitate signal transduction, proliferation, invasion, immune modulation, angiogenesis, and metastasis. Despite the identification of several molecular signalling pathways associated with Golgi abnormalities, there remains a lack of approved drugs specifically targeting cancer cells through the manipulation of the Golgi apparatus. In the initial section of this comprehensive review, the focus is directed towards delineating the abnormal Golgi genes and proteins implicated in carcinogenesis. Subsequently, a thorough examination is conducted on the impact of these variations on Golgi function, encompassing aspects such as vesicular trafficking, glycosylation, autophagy, oxidative mechanisms, and pH alterations. Lastly, the review provides a current update on promising Golgi apparatus-targeted inhibitors undergoing preclinical and/or clinical trials, offering insights into their potential as therapeutic interventions. Significantly more effort is required to advance these potential inhibitors to benefit patients in clinical settings.
  19. Tan A, Babak MV, Venkatesan G, Lim C, Klotz KN, Herr DR, et al.
    Molecules, 2019 Oct 11;24(20).
    PMID: 31614517 DOI: 10.3390/molecules24203661
    Human A3 adenosine receptor hA3AR has been implicated in gastrointestinal cancer, where its cellular expression has been found increased, thus suggesting its potential as a molecular target for novel anticancer compounds. Observation made in our previous work indicated the importance of the carbonyl group of amide in the indolylpyrimidylpiperazine (IPP) for its human A2A adenosine receptor (hA2AAR) subtype binding selectivity over the other AR subtypes. Taking this observation into account, we structurally modified an indolylpyrimidylpiperazine (IPP) scaffold, 1 (a non-selective adenosine receptors' ligand) into a modified IPP (mIPP) scaffold by switching the position of the carbonyl group, resulting in the formation of both ketone and tertiary amine groups in the new scaffold. Results showed that such modification diminished the A2A activity and instead conferred hA3AR agonistic activity. Among the new mIPP derivatives (3-6), compound 4 showed potential as a hA3AR partial agonist, with an Emax of 30% and EC50 of 2.89 ± 0.55 μM. In the cytotoxicity assays, compound 4 also exhibited higher cytotoxicity against both colorectal and liver cancer cells as compared to normal cells. Overall, this new series of compounds provide a promising starting point for further development of potent and selective hA3AR partial agonists for the treatment of gastrointestinal cancers.
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