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1.
Eur J Med Chem ; 280: 116921, 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39388903

RESUMEN

Drug resistance against antimalarials is rendering them increasingly ineffective and so there is a need for the development of new antimalarials. To discover new antimalarial chemotypes a phenotypic screen of the Janssen Jumpstarter library against the P. falciparum asexual stage was undertaken, uncovering the cyclopropyl carboxamide structural hit class. Structure-activity analysis revealed that each structural moiety was largely resistant to change, although small changes led to the frontrunner compound, WJM280, which has potent asexual stage activity (EC50 40 nM) and no human cell cytotoxicity. Forward genetics uncovered that cyclopropyl carboxamide resistant parasites have mutations and an amplification in the cytochrome b gene. Cytochrome b was then verified as the target with profiling against cytochrome b drug-resistant parasites and a mitochondrial oxygen consumption assay. Accordingly, the cyclopropyl carboxamide class was shown to have slow-acting asexual stage activity and activity against male gametes and exoerythrocytic forms. Enhancing metabolic stability to attain efficacy in malaria mouse models remains a challenge in the future development of this antimalarial chemotype.

2.
Clin Microbiol Rev ; : e0010924, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39404268

RESUMEN

SUMMARYThe artemisinin antimalarials are the cornerstone of current malaria treatment. The development of artemisinin resistance in Plasmodium falciparum poses a major threat to malaria control and elimination. Recognized first in the Greater Mekong subregion of Southeast Asia nearly 20 years ago, artemisinin resistance has now been documented in Guyana, South America, in Papua New Guinea, and most recently, it has emerged de novo in East Africa (Rwanda, Uganda, South Sudan, Tanzania, Ethiopia, Eritrea, and eastern DRC) where it has now become firmly established. Artemisinin resistance is associated with mutations in the propeller region of the PfKelch gene, which play a causal role, although the parasites' genetic background also makes an important contribution to the phenotype. Clinically, artemisinin resistance manifests as reduced parasiticidal activity and slower parasite clearance and thus an increased risk of treatment failure following artemisinin-based combination therapy (ACT). This results from the loss of artemisinin activity against the younger circulating ring stage parasites. This loss of activity is likely to diminish the life-saving advantage of artesunate in the treatment of severe falciparum malaria. Gametocytocidal and thus transmission blocking activities are also reduced. At current levels of resistance, artemisinin-resistant parasites still remain susceptible at the trophozoite stage of asexual development, and so, artemisinin still contributes to the therapeutic response. As ACTs are the most widely used antimalarial drugs in the world, it is essential from a malaria control perspective that ACT cure rates remain high. Better methods of identifying uncomplicated hyperparasitemia, the main cause of ACT treatment failure, are required so that longer courses of treatment can be given to these high-risk patients. Reducing the use of artemisinin monotherapies will reduce the continued selection pressure which could lead potentially to higher levels of artemisinin resistance. Triple artemisinin combination therapies should be deployed as soon as possible to protect the ACT partner drugs and thereby delay the emergence of higher levels of resistance. As new affordable antimalarial drugs are still several years away, the control of artemisinin resistance must depend on the better use of available tools.

3.
Chem Biodivers ; : e202401576, 2024 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-39400985

RESUMEN

Calophyllum tomentosum belonging to Clusiaceae family is an Indian medicinal plant used as folklore medicine to cure various kinds of diseases reported in Ayurveda, and the leaves of the plant are also used as an active ingredient for the preparation of a botanical medicine known as 'Punnaga', 'Surapunnaga' and 'Tamoil' among other common names. Chemical profiling of the methanol extract of the defatted leaf revealed the presence of amentoflavone as one of the constituents along with coumarins, terpenoids, steroids, and apetalic acids. Structural determination of these amentoflavone has been conducted by chemical, spectral, and spectrometric methods in comparison with spectral values available in the literature and confirmed by a single crystal X-ray diffraction study. Amentoflavone (1) and its derivative (2-5) tested to check the efficacy of anti-malarial activity against Plasmodium falciparum. Amongst them, only tetra methoxy amentoflavone, (2) exhibited moderate anti-malarial activity with IC50 value 1.99 ± 0.42 µM against Plasmodium falciparum in comparison with artemisinin as control, whereas the other products possessed almost negligible activity although their structural skeletons are identical with little variation of number and nature of substituents. The structure activity relationship (SAR) of the active constituent and its derivatives is reported herein.

4.
Prog Med Chem ; 63(1): 161-234, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39370241

RESUMEN

Malaria remains a devastating but preventable infectious disease that disproportionately affects the African continent. Emerging resistance to current frontline therapies means that not only are new treatments urgently required, but also novel validated antimalarial targets to circumvent cross-resistance. Fortunately, tremendous efforts have been made by the global drug discovery community over the past decade. In this chapter, we will highlight some of the antimalarial drug discovery and development programmes currently underway across the globe, charting progress in the identification of new targets and the development of new classes of drugs to prosecute them. These efforts have been complemented by the development of valuable tools to accelerate target validation such as the NOD scid gamma (NSG) humanized mouse efficacy model and progress in predictive modelling and open-source software. Among the medicinal chemistry programmes that have been conducted over the past decade are those targeting Plasmodium falciparum ATPase4 (ATP4) and acetyl-CoA synthetase (AcAS) as well as proteins disrupting parasite protein translation such as the aminoacyl-tRNA synthetases (aaRSs) and eukaryotic elongation factor 2 (eEF2). The benefits and challenges of targeting Plasmodium kinases will be examined, with a focus on Plasmodium cyclic GMP-dependent protein kinase (PKG), cyclin-dependent-like protein kinase 3 (CLK3) and phosphatidylinositol 4-kinase (PI4K). The chapter concludes with a survey of incipient drug discovery centres in Africa and acknowledges the value of recent international meetings in galvanizing and uniting the antimalarial drug discovery community.


Asunto(s)
Antimaláricos , Descubrimiento de Drogas , Antimaláricos/farmacología , Antimaláricos/química , Antimaláricos/uso terapéutico , Humanos , Animales , Malaria/tratamiento farmacológico , Plasmodium falciparum/efectos de los fármacos
5.
Adv Appl Bioinform Chem ; 17: 83-105, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39345873

RESUMEN

Background: Existing antimalarial drugs primarily target blood-stage parasites, but there is a need for transmission-blocking drugs to combat malaria effectively. Plasmodium falciparum Calcium-dependent Protein Kinase 4 (CDPK4) is a promising target for such drugs. This study employed advanced in silico analyses of hexahydroquinolines (HHQ) derivatives to identify PfCDPK4 inhibitors capable of disrupting malaria transmission. Structure-based virtual screening (SBVS) was employed to discover HHQ derivatives with the highest binding affinities against the 3D structure of PfCDPK4 (PDB 1D: 4QOX). Methods: Interaction analysis of protein-ligand complexes utilized Discovery Studio Client, while druglikeness and ADMET properties were assessed using SwissADME and pkCSM web servers, respectively. Quantum mechanical calculations of the top hits were conducted using density functional theory (DFT), and GROMACS was employed to perform the molecular dynamics (MD) simulations. Binding free energy was predicted using the MMPBSA.py tool from the AMBER package. Results: SBVS identified ten best hits possessing docking scores within the range of -11.2 kcal/mol and -10.6 kcal/mol, surpassing the known inhibitor, BKI-1294 (-9.9 kcal/mol). Among these, 4-[4-(Furan-2-carbonyl)piperazin-1-yl]-1-(naphthalen-2-ylmethyl)-2-oxo-4a,5,6,7,8,8a-hexahydroquinoline-3-carbonitrile (PubChem ID: 145784778) exhibited the highest binding affinity (-11.2 kcal/mol) against PfCDPK4. Conclusion: Comparative analysis of this compound with BKI-1294 using advanced computational approaches demonstrated competitive potential. These findings suggest the potential of 4-[4-(Furan-2-carbonyl)piperazin-1-yl]-1-(naphthalen-2-ylmethyl)-2-oxo-4a,5,6,7,8,8a-hexahydroquinoline-3-carbonitrile as a promising PfCDPK4 inhibitor for disrupting malaria transmission. However, further experimental studies are warranted to validate its efficacy and safety profile.

6.
Chemistry ; : e202403408, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39348488

RESUMEN

A total synthesis of the enantiopure syn,syn-tosyl-samroiyotmycin A, a C2-symmetric 20-membered antimalarial macrodiolide with syn,syn-configuration of the 8,24-dihydroxy-9,25-dimethyl units and it's enantiopure anti,anti-derivative is described. The synthesis was accomplished utilizing a linear approach in 7 steps and 3 % overall yield via a sequence of diastereoselective methylation of SuperQuat oxazolidinone auxiliary, cross metathesis and Yamaguchi macrolactonization of fully functionalized seco-acids. By a similar approach we gained access to several samroiyotmycin analogues and precursors. Antimalarial activity was tested on multi-resistant (K1) and sensitive (Nf54) P. falciparum strains providing insight into structure activity relationships. Both tosyl-oxazol unit as well as the syn-configuration of the two contiguous stereogenic centers turned out to be beneficial for antiplasmodial activity. For instance, syn,syn-tosyl-samroiyotmycin A showed 3.4 times higher activities than the "tosyl-free" natural product.

7.
BMC Infect Dis ; 24(1): 1028, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39327613

RESUMEN

BACKGROUND: The World Health Organization 2022 malaria chemoprevention guidelines recommend providing a full course of antimalarial treatment at pre-defined intervals, regardless of malaria status to prevent illness among children resident in moderate to high perennial malaria transmission settings as perennial malaria chemoprevention (PMC) with sulfadoxine-pyrimethamine (SP). The dhps I431V mutation circulating in West Africa has unknown effect on SP protective efficacy. METHODS: This protocol is for a three-arm, parallel, double-blinded, placebo-controlled, randomised trial in Cameroon among children randomly assigned to one of three directly-observed treatment groups: (i) Group 1 (n = 450) receives daily artesunate (AS) placebo on days - 7 to -1, then active SP plus placebo amodiaquine (AQ) on day 0, and placebo AQ on days 1 and 2; (ii) Group 2 (n = 250) receives placebo AS on days - 7 to -1, then active SP and AQ on day 0, and active AQ on days 1 and 2; and (iii) Group 3 (n = 200) receives active AS on days - 7 to -1, then placebo SP on day 0 and placebo AQ on days 0 to 2. On days 0, 2, 5, 7, and thereafter weekly until day 28, children provide blood for thick smear slides. Dried blood spots are collected on the same days and weekly from day 28 to day 63 for quantitative polymerase chain reaction (qPCR) and genotype analyses. DISCUSSION: Our aim is to quantify the chemopreventive efficacy of SP, and SP plus AQ, and measure the effect of the parasite genotypes associated with SP resistance on parasite clearance and protection from infection when exposed to SP chemoprevention. We will report unblinded results including: (i) time-to-parasite clearance among SP and SP plus AQ recipients who were positive on day 0 by qPCR and followed to day 63; (ii) mean duration of SP and SP plus AQ protection against infection, and (iii) mean duration of symptom-free status among SP and SP plus AQ recipients who were parasite free on day 0 by qPCR. Our study is designed to compare the 28-day follow-up of the new WHO malaria chemoprevention efficacy study protocol with extended follow-up to day 63. TRIAL REGISTRATION: ClinicalTrials.gov NCT06173206; 15/12/2023.


Asunto(s)
Amodiaquina , Antimaláricos , Artesunato , Combinación de Medicamentos , Malaria Falciparum , Plasmodium falciparum , Pirimetamina , Sulfadoxina , Humanos , Pirimetamina/uso terapéutico , Pirimetamina/administración & dosificación , Camerún , Sulfadoxina/uso terapéutico , Sulfadoxina/administración & dosificación , Malaria Falciparum/prevención & control , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/parasitología , Antimaláricos/uso terapéutico , Antimaláricos/administración & dosificación , Preescolar , Amodiaquina/uso terapéutico , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/genética , Método Doble Ciego , Femenino , Masculino , Artesunato/uso terapéutico , Artemisininas/uso terapéutico , Artemisininas/administración & dosificación , Resultado del Tratamiento , Quimioprevención/métodos
8.
Malar J ; 23(1): 283, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39289709

RESUMEN

BACKGROUND: Cardiovascular events following anti-malarial treatment are reported infrequently; only a few studies have reported adverse outcomes. This case presentation emphasizes cardiological assessment of Brugada syndrome, presenting as life-threatening arrhythmia during anti-malarial treatment. Without screening and untreated, this disease may lead to sudden cardiac death. CASE PRESENTATION: This is a case of 23-year-old male who initially presented with palpitations followed by syncope and shortness of breath with a history of malaria. He had switched treatment from quinine to dihydroartemisinin-piperaquine (DHP). Further investigations revealed the ST elevation electrocardiogram pattern typical of Brugada syndrome, confirmed with flecainide challenge test. Subsequently, anti-malarial treatment was stopped and an Implantable Cardioverter Defibrillator (ICD) was inserted. CONCLUSIONS: Another possible cause of arrhythmic events happened following anti-malarial consumption. This case highlights the possibility of proarrhytmogenic mechanism of malaria infection and anti-malarial drug resulting in typical manifestations of Brugada syndrome.


Asunto(s)
Antimaláricos , Artemisininas , Síndrome de Brugada , Quinolinas , Humanos , Masculino , Antimaláricos/uso terapéutico , Antimaláricos/efectos adversos , Artemisininas/uso terapéutico , Artemisininas/efectos adversos , Adulto Joven , Quinolinas/uso terapéutico , Quinolinas/efectos adversos , Malaria/tratamiento farmacológico , Malaria/complicaciones , Electrocardiografía , Piperazinas
9.
Int J Pharm ; 666: 124746, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39321903

RESUMEN

Malaria, caused by Plasmodium parasites transmitted through Anopheles mosquitoes, remains a global health burden, particularly in tropical regions. The most lethal species, Plasmodium falciparum and Plasmodium vivax, pose significant threats to human health. Despite various treatment strategies, malaria continues to claim lives, with Africa being disproportionately affected. This review explores the advancements in drug delivery systems for malaria treatment, focusing on polymeric and lipid-based nanoparticles. Traditional antimalarial drugs, while effective, face challenges such as toxicity and poor bio-distribution. To overcome these issues, nanocarrier systems have been developed, aiming to enhance drug efficacy, control release, and minimize side effects. Polymeric nanocapsules, dendrimers, micelles, liposomes, lipid nanoparticles, niosomes, and exosomes loaded with antimalarial drugs are examined, providing a comprehensive overview of recent developments in nanotechnology for malaria treatment. The current state of antimalarial treatment, including combination therapies and prophylactic drugs, is discussed, with a focus on the World Health Organization's recommendations. The importance of nanocarriers in malaria management is underscored, highlighting their role in targeted drug delivery, controlled release, and improved pharmacological properties. This review bridges the gap in the literature, consolidating the latest advancements in nanocarrier systems for malaria treatment and offering insights into potential future developments in the field.

10.
Future Microbiol ; 19(15): 1293-1307, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39235058

RESUMEN

Aim: To assess the functional relevance of a putative Major Facilitator Superfamily protein (PF3D7_0210300; 'PfMFSDT') as a drug transporter, using Candida glabrata for orthologous protein expression.Methods: Complementary Determining Sequence encoding PfMFSDT was integrated into the genome of genetically engineered C. glabrata strain MSY8 via homologous recombination, followed by assessing its functional relevance as a drug transporter.Results & conclusion: The modified C. glabrata strain exhibited plasma membrane localization of PfMFSDT and characteristics of an Major Facilitator Superfamily transporter, conferring resistance to antifungals, ketoconazole and itraconazole. The nanomolar inhibitory effects of the drugs on the intra-erythrocytic growth of Plasmodium falciparum highlight their antimalarial properties. This study proposes PfMFSDT as a drug transporter, expanding the repertoire of the currently known antimalarial 'resistome'.


[Box: see text].


Asunto(s)
Antifúngicos , Antimaláricos , Candida glabrata , Proteínas de Transporte de Membrana , Plasmodium falciparum , Plasmodium falciparum/genética , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/metabolismo , Antifúngicos/farmacología , Antifúngicos/metabolismo , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Candida glabrata/genética , Candida glabrata/metabolismo , Candida glabrata/efectos de los fármacos , Antimaláricos/farmacología , Antimaláricos/metabolismo , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Itraconazol/farmacología , Cetoconazol/farmacología , Humanos , Membrana Celular/metabolismo
11.
Antimicrob Agents Chemother ; 68(10): e0074624, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39264187

RESUMEN

A revamped in vitro compound identification and activity profiling approach is required to meet the large unmet need for new anti-malarial drugs to combat parasite drug resistance. Although compound hit identification utilizing high-throughput screening of large compound libraries is well established, the ability to rapidly prioritize such large numbers for further development is limited. Determining the speed of action of anti-malarial drug candidates is a vital component of malaria drug discovery, which currently occurs predominantly in lead optimization and development. This is due in part to the capacity of current methods which have low throughput due to the complexity and labor intensity of the approaches. Here, we provide an adaptable screening paradigm utilizing automated high content imaging, including the development of an automated schizont maturation assay, which collectively can identify anti-malarial compounds, classify activity into fast and slow acting, and provide an indication of the parasite stage specificity, with high-throughput capability. By frontloading these critical biological parameters much earlier in the drug discovery pipeline, it has the potential to reduce lead compound attrition rates later in the development process. The capability of the approach in its alternative formats is demonstrated using three Medicines for Malaria Venture open access compound "boxes," namely Pathogen Box (malaria set-125 compounds), Global Health Priority Box [Malaria Box 2 (80 compounds) and zoonotic neglected diseases (80 compounds)], and the Pandemic Response Box (400 compounds). From a total of 685 compounds tested, 79 were identified as having fast ring-stage-specific activity comparable to that of artemisinin and therefore of high priority for further consideration and development.


Asunto(s)
Antimaláricos , Ensayos Analíticos de Alto Rendimiento , Antimaláricos/farmacología , Ensayos Analíticos de Alto Rendimiento/métodos , Plasmodium falciparum/efectos de los fármacos , Humanos , Descubrimiento de Drogas/métodos , Malaria/tratamiento farmacológico , Animales , Pruebas de Sensibilidad Parasitaria/métodos
12.
Trop Life Sci Res ; 35(2): 167-185, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39234468

RESUMEN

The antimalarial properties of crude extracts from Quercus infectoria galls were investigated through bioassay-guided fractionation. Acetone (QIA) and methanol (QIM) crude extracts have been reported to have promising antimalarial activity against Plasmodium falciparum (3D7 strain). These extracts were subjected to fractionation using automated preparative high-performance liquid chromatography (prep-HPLC) to identify the most active fractions. Nine fractions were isolated from each extract, of which the fractions QIA11 and QIM16 showed antimalarial activity, with IC50 values of 17.65 ± 1.82 µg/mL and 24.21 ± 1.88 µg/mL, respectively. In comparison, the standard antimalarial drug artemisinin has an IC50 value of 0.004 ± 0.001 µg/mL). Through high-resolution liquid chromatography coupled with mass spectrometry (HR-LCMS) analysis of the fractions, four known compounds were successfully identified: gallic acid, ellagic acid, 1,3,6-tris-o-(3,4,5-trihydroxybenzoyl)-beta-d-glucose and 1-O,6-O-digalloyl-beta-D-glucose.

13.
Bioorg Chem ; 153: 107754, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39241585

RESUMEN

Malaria remains a severe global health concern, with 249 million cases reported in 2022, according to the World Health Organization (WHO) [1]. PfDHODH is an essential enzyme in malaria parasites that helps to synthesize certain building blocks for their growth and development. It has been confirmed that targeting Plasmodium falciparum dihydroorotate dehydrogenase (PfDHODH) enzyme could lead to new and effective antimalarial drugs. Inhibitors of PfDHODH have shown potential for slowing down parasite growth during both the blood and liver stages. Over the last two decades, many species selective PfDHODH inhibitors have been designed, including DSM compounds and other non-DSM compounds. In the first chapter [2] of this review, we have reviewed all synthetic schemes and structure-activity relationship (SAR) studies of DSM compounds. In this second chapter, we have compiled all the other non-DSM PfDHODH inhibitors based on dihydrothiophenones, thiazoles, hydroxyazoles, and N-alkyl-thiophene-2-carboxamides. The review not only offers an insightful overview of the synthetic methods employed but also explores into alternative routes and innovative strategies involving different catalysts and chemical reagents. A critical aspect covered in the review is the SAR studies, which provide a comprehensive understanding of how structural modifications impact the efficacy of PfDHODH inhibitors and challenges related to the discovery of PfDHODH inhibitors. This information is invaluable for scientists engaged in the development of new antimalarial drugs, offering insights into the most promising scaffolds and their synthetic techniques.

14.
Bioorg Chem ; 153: 107789, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39250850

RESUMEN

Recently, P218, a new flexible antifolate targeting Plasmodium falciparum dihydrofolate reductase (PfDHFR), has entered its clinical trial with good safety profile and effective Pf infection prevention. However, it carries a free carboxyl terminal, which is hydrophilic and prone to metabolic glucuronidation. Here, a new series of P218 analogues carrying butyrolactone has been synthesized with the purpose of enhancing lipophilicity and minimizing metabolic instability. The inhibition constants against the mutant PfDHFR enzymes are in sub-nanomolar level and the antimalarial activity against antifolate-resistant parasites are in the low micromolar range. The crystal structure of the most potent analogue LA1 bound enzyme complex indicates interaction with multiple residues, including Arg122 and Phe116 in the active site. In vitro log D7.4 and kinetic solubility confirmed a higher lipophilicity of this butyrolactone series as compared to P218. These outcomes suggest the possibility to further develop butyrolactone derivatives as non-carboxyl antiplasmodial antifolates.

15.
J Biomater Sci Polym Ed ; : 1-17, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39217616

RESUMEN

Primaquine (PQ) is a widely used antimalarial drug, but its high dosage requirements can lead to significant tissue damage and adverse gastrointestinal and hematological effects. Recent studies have shown that nanoformulations can enhance the bioavailability of pharmaceuticals, thereby increasing efficacy, reducing dosing frequency, and minimizing toxicity. In this study, PQ-loaded PLGA nanoparticles (PQ-NPs) were prepared using a modified double emulsion solvent evaporation technique (w/o/w). The PQ-NPs exhibited a mean particle size of 228 ± 2.6 nm, a zeta potential of +27.4 mV, and an encapsulation efficiency of 81.3 ± 3.5%. Scanning electron microscopy (SEM) confirmed their spherical morphology, and the in vitro release profile demonstrated continuous drug release over 72 h. Differential scanning calorimetry (DSC) thermograms indicated that the drug was present in the nanoparticles, with improved physical stability. Fourier-transform infrared spectroscopy (FTIR) analysis showed no interactions between the various substances in the NPs. In vivo studies in Swiss albino mice infected with Plasmodium berghei revealed that the nanoformulated PQ was 20% more effective than the standard oral dose. Biodistribution studies indicated that 80% of the NPs accumulated in the liver, highlighting their potential for targeted drug delivery. This research demonstrates the successful development of a nanomedicine delivery system for antimalarial drugs, offering a promising strategy to enhance treatment efficacy while reducing adverse effects.

16.
Bioorg Med Chem Lett ; 113: 129947, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39245150

RESUMEN

Previously, we successfully introduced laeA gene into a fungal strain in order to significantly increase the production of a bioactive compound, allowing use to discover novel biological activity. To demonstrate the universal applicability of the laeA gene introduction strategy for taping the potential of fungal secondary metabolism, in this present study, we created a library of microorganisms which we had the laeA gene inserted, and from that library we aimed to isolate compounds which are produced at significantly greater quantities compared to the respective wild type strains. From this investigation, we were able to isolate sclerotinin A (1) from Pochonia sp. KTF-0504 strain. We revealed that 1 showed anti-malarial activity against Plasmodium falciparum parasite strains. On the other hands, 1 showed no anti-fungal activity against multidrug-sensitive budding yeast. Our study implies that the utilization of the laeA gene in fungi is a versatile method for the discovery of drug candidates.

17.
Eur J Med Chem ; 278: 116796, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39241483

RESUMEN

To achieve malaria eradication, new preventative agents that act differently to front-line treatment drugs are needed. To identify potential chemoprevention starting points we screened a sub-set of the CSIRO Australia Compound Collection for compounds with slow-action in vitro activity against Plasmodium falciparum. This work identified N,N-dialkyl-5-alkylsulfonyl-1,3,4-oxadiazol-2-amines as a new antiplasmodial chemotype (e.g., 1 96 h IC50 550 nM; 3 96 h IC50 160 nM) with a different action to delayed-death slow-action drugs. A series of analogues were synthesized from thiotetrazoles and carbomoyl derivatives using Huisgen 1,3,4-oxadiazole synthesis followed by oxidation of the resultant thioethers to target sulfones. Structure activity relationship analysis of analogues identified compounds with potent and selective in vitro activity against drug-sensitive and multi-drug resistant Plasmodium parasites (e.g., 31 and 32 96 h IC50 <40 nM; SI > 2500). Subsequent studies in mice with compound 1, which had the best microsomal stability of the compounds assessed (T1/2 >255 min), demonstrated rapid clearance and poor oral in vivo efficacy in a P. berghei murine malaria model. These data indicate that while N,N-dialkyl-5-alkylsulfonyl-1,3,4-oxadiazol-2-amines are a novel class of slow-acting antiplasmodial agents, the further development of this chemotype for malaria chemoprophylaxis will require pharmacokinetic profile improvements.


Asunto(s)
Antimaláricos , Oxadiazoles , Plasmodium falciparum , Oxadiazoles/química , Oxadiazoles/farmacología , Oxadiazoles/síntesis química , Plasmodium falciparum/efectos de los fármacos , Antimaláricos/farmacología , Antimaláricos/química , Antimaláricos/síntesis química , Animales , Relación Estructura-Actividad , Ratones , Pruebas de Sensibilidad Parasitaria , Estructura Molecular , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Humanos , Malaria Falciparum/tratamiento farmacológico
18.
J Parasit Dis ; 48(2): 269-282, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39297004

RESUMEN

Plasmodium parasite causes malaria and affects the biochemical, physiological, and histoarchitecture of the hepatocytes and blood. The resultant effect leads to alterations in the metabolic activities of the liver, erythrocytes, as well as the buffer system. Therefore, we investigated the antiplasmodial activity, histomorphological studies of the hepatocytes and alterations in biochemical parameters in Plasmodium berghei-infected mice administered with the herbal formulation of aqueous extracts of Mangifera indica stem bark and leaves. The plant coarse leaves (250.71 g) and stem bark (509.34 g) were weighed to obtain their ratios, macerated in boiled distilled water (5 L) for 72 h, filtered, and concentrated to obtain the various extracts whereas LD50 calculation gave 5500.19 mg/kg. The extracts were administered to eleven groups of mice at a dosage of 300 mg/kg whereas artesunate and ACT served as the positive control drugs; the antiplasmodial profiling, biochemical, and histological evaluations followed standard protocols. The schizonticidal activity of the extracts were remarkable; moreover, the histological section of the liver (negative control) had increased deposition of hemozoin, sinusoidal congestions, activation of kupffer cells, and portal tract inflammations; however, the other treatment groups in the study drastically reduced inflammation. The biochemical parameters' results revealed metabolic acidosis mitigation; hypocholesterolemia induction; enhanced hyperproteinemia, as well as hypoglycemia mitigation. The antiplasmodial therapeutic response, and biochemical derangements reversal corroborated with improved hepatocytes histoarchitecture of mice highlights the plant's pharmacological efficacy. (Word counts: 227).

19.
Int J Mol Sci ; 25(17)2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39273572

RESUMEN

Chalcones have been utilized for centuries as foods and medicines across various cultures and traditions worldwide. This paper concisely overviews their biosynthesis as specialized metabolites in plants and their significance, potential, efficacy, and possibility as future medicines. This is followed by a more in-depth exploration of naturally occurring chalcones and their corresponding mechanisms of action in human bodies. Based on their mechanisms of action, chalcones exhibit many pharmacological properties, including antioxidant, anti-inflammatory, anticancer, antimalarial, antiviral, and antibacterial properties. Novel naturally occurring chalcones are also recognized as potential antidiabetic drugs, and their effect on the GLUT-4 transporter is investigated. In addition, they are examined for their anti-inflammatory effects, focusing on chalcones used for future pharmaceutical utilization. Chalcones also bind to specific receptors and toxins that prevent bacterial and viral infections. Chalcones exhibit physiological protective effects on the biological degradation of different systems, including demyelinating neurodegenerative diseases and preventing hypertension or hyperlipidemia. Chalcones that are/were in clinical trials have been included as a separate section. By revealing the many biological roles of chalcones and their impact on medicine, this paper underlines the significance of naturally occurring chalcones and their extension to patient care, providing the audience with an index of topic-relevant information.


Asunto(s)
Chalconas , Chalconas/farmacología , Chalconas/química , Humanos , Ensayos Clínicos como Asunto , Animales , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinflamatorios/uso terapéutico , Antioxidantes/farmacología , Antioxidantes/química , Hipoglucemiantes/farmacología , Hipoglucemiantes/química , Hipoglucemiantes/uso terapéutico , Productos Biológicos/farmacología , Productos Biológicos/química , Productos Biológicos/uso terapéutico
20.
Curr Top Med Chem ; 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39313876

RESUMEN

Among heterocyclic compounds, quinoline is one of the best ubiquitous heterocyclic rings for medicinal chemistry purposes. Quinoline appears to be a powerful chemical structure to develop new drug entities. The quinoline derivatives own a wide array of biological activities such as anticancer, antimalarial, antimicrobial, anti-inflammatory, anti-leishmanial, etc. Because of the wide spectrum of bioactivities, the scientific communities are still looking for more efficient synthetic routes to form quinoline derivatives. Therefore, the primary focus of this review is to provide a thorough and inclusive, updated report on quinoline analogs that may pave the way for more efficient drug development.

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