In vivo antimalarial activity of Keetia leucantha twigs extracts and in vitro antiplasmodial effect of their constituents

Background: Malaria is one of the most devastating parasitic diseases, yet the discovery of antimalarial agents remains profoundly challenging. Very few new antimalarials have been developed in the past 50 years, while the emergence of drug-resistance continues to appear. Objective: This study focuses on the discovery, design, synthesis, and antimalarial evaluation of 3-cinnamamido-N-substituted benzamides. Method: In this study, a screening of our compound library was carried out against the multidrug-sensitive Plasmodium falciparum 3D7 strain. Derivatives of the hit were designed, synthesized and tested against P. falciparum 3D7 and the in vivo antimalarial activity of the most active compounds was evaluated using the method of Peters’ 4-day suppressive test. Results: The retrieved hit compound 1 containing a 3-cinnamamido-N-substituted benzamide skeleton showed moderate antimalarial activity (IC50 = 1.20 µM) for the first time. A series of derivatives were then synthesized through a simple four-step workflow, and half of them exhibited slightly better antimalarial effect than the precursor 1 during the subsequent in vitro assays. Additionally, compounds 11, 23, 30 and 31 displayed potent activity with IC50 values of approximately 0.1 µM, and weak cytotoxicity against mammalian cells. However, in vivo antimalarial activity is not effective which might be ascribed to the poor solubility of these compounds. Conclusion: In this study, phenotypic screen of our compound library resulted in the first report of 3-cinnamamide framework with antimalarial activity and 40 derivatives were then designed and synthesized. Subsequent structure-activity studies showed that compounds 11, 23, 30 and 31 exhibited the most potent and selective activity against P. falciparum 3D7 strain with IC50 values around 0.1 µM. Our work herein sets another example of phenotypic screen-based drug discovery, leading to potentially promising candidates of novel antimalarial agents once given further optimization.

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Stage-dependent effect of deferoxamine on growth of Plasmodium falciparum in vitro

Blood ◽

10.1182/blood.v76.6.1250.1250 ◽

1990 ◽

Vol 76 (6) ◽

pp. 1250-1255 ◽

Cited By ~ 36

Author(s):

S Whitehead ◽

TE Peto

Keyword(s):

Plasmodium Falciparum ◽

Growth Inhibition ◽

Antimalarial Activity ◽

Clinical Malaria ◽

Inhibitory Effect ◽

Parasite Development ◽

And Control ◽

Speed Of Onset

Abstract Deferoxamine (DF) has antimalarial activity that can be demonstrated in vitro and in vivo. This study is designed to examine the speed of onset and stage dependency of growth inhibition by DF and to determine whether its antimalarial activity is cytostatic or cytocidal. Growth inhibition was assessed by suppression of hypoxanthine incorporation and differences in morphologic appearance between treated and control parasites. Using synchronized in vitro cultures of Plasmodium falciparum, growth inhibition by DF was detected within a single parasite cycle. Ring and nonpigmented trophozoite stages were sensitive to the inhibitory effect of DF but cytostatic antimalarial activity was suggested by evidence of parasite recovery in later cycles. However, profound growth inhibition, with no evidence of subsequent recovery, occurred when pigmented trophozoites and early schizonts were exposed to DF. At this stage in parasite development, the activity of DF was cytocidal and furthermore, the critical period of exposure may be as short as 6 hours. These observations suggest that iron chelators may have a role in the treatment of clinical malaria.

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Antimalarial Effect of the Total Glycosides of the Medicinal Plant, Ranunculus japonicus

Pathogens ◽

10.3390/pathogens10050532 ◽

2021 ◽

Vol 10 (5) ◽

pp. 532

Author(s):

Hae-Soo Yun ◽

Sylvatrie-Danne Dinzouna-Boutamba ◽

Sanghyun Lee ◽

Zin Moon ◽

Dongmi Kwak ◽

...

Keyword(s):

Chinese Medicine ◽

Traditional Chinese Medicine ◽

Plasmodium Berghei ◽

Antimalarial Activity ◽

Hematological Parameters ◽

Significant Inhibition ◽

Ic50 Values ◽

The Republic

In traditional Chinese medicine, Ranunculus japonicus has been used to treat various diseases, including malaria, and the young stem of R. japonicus is consumed as a food in the Republic of Korea. However, experimental evidence of the antimalarial effect of R. japonicus has not been evaluated. Therefore, the antimalarial activity of the extract of the young stem of R. japonicus was evaluated in vitro using both chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) strains; in vivo activity was evaluated in Plasmodium berghei-infected mice via oral administration followed by a four-day suppressive test focused on biochemical and hematological parameters. Exposure to extracts of R. japonicus resulted in significant inhibition of both chloroquine-sensitive (3D7) and resistant (Dd2) strains of P. falciparum, with IC50 values of 6.29 ± 2.78 and 5.36 ± 4.93 μg/mL, respectively. Administration of R. japonicus also resulted in potent antimalarial activity against P. berghei in infected mice with no associated toxicity; treatment also resulted in improved hepatic, renal, and hematologic parameters. These results demonstrate the antimalarial effects of R. japonicus both in vitro and in vivo with no apparent toxicity.

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Synthetic spirocyclic endoperoxides: new antimalarial scaffolds

MedChemComm ◽

10.1039/c4md00454j ◽

2015 ◽

Vol 6 (2) ◽

pp. 357-362 ◽

Cited By ~ 31

Author(s):

Margherita Brindisi ◽

Sandra Gemma ◽

Sanil Kunjir ◽

Luisa Di Cerbo ◽

Simone Brogi ◽

...

Keyword(s):

Molecular Docking ◽

Antimalarial Activity ◽

Design Synthesis ◽

Docking Calculation

Design, synthesis and molecular docking calculation studies led to the identification of novel spirocyclic peroxides with in vitro and in vivo antimalarial activity.

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Antimalarial activity of betulinic acid and derivatives in vitro against Plasmodium falciparum and in vivo in P. berghei-infected mice

Parasitology Research ◽

10.1007/s00436-009-1394-0 ◽

2009 ◽

Vol 105 (1) ◽

pp. 275-279 ◽

Cited By ~ 46

Author(s):

Matheus Santos de Sá ◽

José Fernando Oliveira Costa ◽

Antoniana Ursine Krettli ◽

Mariano Gustavo Zalis ◽

Gabriela Lemos de Azevedo Maia ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Betulinic Acid ◽

Antimalarial Activity

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In VitroandIn VivoActivity of Solithromycin (CEM-101) against Plasmodium Species

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.05039-11 ◽

2011 ◽

Vol 56 (2) ◽

pp. 703-707 ◽

Cited By ~ 11

Author(s):

Sergio Wittlin ◽

Eric Ekland ◽

J Carl Craft ◽

Julie Lotharius ◽

Ian Bathurst ◽

...

Keyword(s):

Drug Exposure ◽

Antimalarial Activity ◽

Plasmodium Species ◽

Parasite Clearance ◽

Response To Treatment ◽

Cross Resistance ◽

Asexual Blood Stage ◽

Content Type

ABSTRACTWith the emergence ofPlasmodium falciparuminfections exhibiting increased parasite clearance times in response to treatment with artemisinin-based combination therapies, the need for new therapeutic agents is urgent. Solithromycin, a potent new fluoroketolide currently in development, has been shown to be an effective, broad-spectrum antimicrobial agent. Malarial parasites possess an unusual organelle, termed the apicoplast, which carries a cryptic genome of prokaryotic origin that encodes its own translation and transcription machinery. Given the similarity of apicoplast and bacterial ribosomes, we have examined solithromycin for antimalarial activity. Other antibiotics known to target the apicoplast, such as the macrolide azithromycin, demonstrate a delayed-death effect, whereby treated asexual blood-stage parasites die in the second generation of drug exposure. Solithromycin demonstrated potentin vitroactivity against the NF54 strain ofP. falciparum, as well as against two multidrug-resistant strains, Dd2 and 7G8. The dramatic increase in potency observed after two generations of exposure suggests that it targets the apicoplast. Solithromycin also retained potency against azithromycin-resistant parasites derived from Dd2 and 7G8, although these lines did demonstrate a degree of cross-resistance. In anin vivomodel ofP. bergheiinfection in mice, solithromycin demonstrated a 100% cure rate when administered as a dosage regimen of four doses of 100 mg/kg of body weight, the same dose required for artesunate or chloroquine to achieve 100% cure rates in this rodent malaria model. These promisingin vitroandin vivodata support further investigations into the development of solithromycin as an antimalarial agent.

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Antimalaria Activity of Cassia spectabilis DC Leaf and Its Inhibition Effect in Heme Detoxification

10.21203/rs.2.22061/v1 ◽

2020 ◽

Author(s):

Wiwied - Ekasari ◽

Dewi Resty Basuki ◽

Heny - Arwati ◽

Tutik Sri Wahy

Keyword(s):

Antimalarial Activity ◽

Ethanol Extract ◽

Ic50 Value ◽

Cassia Spectabilis ◽

In Vivo Testing ◽

Chloroquine Diphosphate ◽

Better Than

Abstract Background In previous studies, Cassia spectabilis DC leaf has shown a good antimalarial activity. Therefore, this study is a follow-up study of leaf activity and mechanism of C. spectabilis DC as an antimalarial. Methods In vitro antimalarial activity testing using P. falciparum which was done with bioassay guide isolation in order to obtain the active compound. In vivo testing towards infected P. berghei mice was conducted to determine the effects of antimalarial prophylaxis and antimalarial activity in combination with artesunate. Whereas, heme detoxification inhibition testing as one of the antimalarial mechanisms was carried out using the Basilico method. Results The results showed that active antimalarial isolate obtained from C. spectabilis DC leaf had a structural pattern that was identical to (-)-7-hydroxyspectaline. Prophylactic test on infected P. berghei mice obtained the highest dose of inhibition percentage of 90% ethanol extract of C. spectabilis DC leaf was 68.61% while positive (doxycycline) control at 100 mg kg-1 was 73.54%. In antimalarial testing in combination with artesunate, it was found that administering 150 mg kg-1 (three times a day) of C. spectabilis DC (D0 − D2) + artesunate (D2) was better than the standard combination of amodiaquine + artesunate with 99.18% and 92.88% inhibition percentage. For the inhibitory activity of heme detoxification from ethanol extract 90%, C. spectabilis DC leaf had IC50 value of 0.375 mg mL-1 which was better than chloroquine diphosphate. Conclusion These results showed that C. spectabilis DC leaves possesses potent antimalarial activity and may offer a potential agent for effective and affordable antimalarial phytomedicine.

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The effect of N-alkyl modification on the antimalarial activity of 3- hydroxypyridin-4-one oral iron chelators

Blood ◽

10.1182/blood.v77.3.637.637 ◽

1991 ◽

Vol 77 (3) ◽

pp. 637-643 ◽

Cited By ~ 38

Author(s):

C Hershko ◽

EN Theanacho ◽

DT Spira ◽

HH Peter ◽

P Dobbin ◽

...

Keyword(s):

Antimalarial Activity ◽

Iron Chelators ◽

Lipid Solubility ◽

Lipophilic Compounds ◽

Labile Iron Pool ◽

Ring Nitrogen ◽

Iron Pool ◽

Chelating Compounds

Abstract The antimalaria effect of iron chelators is attributed to their interaction with a labile iron pool within parasitised erythrocytes, and it was postulated that increased affinity to iron as well as increased lipophilicity may improve antimalarial activity. In the present study we have examined the antimalarial effect of 3- hydroxypyridin-4-ones, a family of bidentate orally effective iron chelators whose lipophilicity may be modified by altering the length of the R2 substituent on the ring nitrogen. A significant dose-related suppression of Plasmodium falciparum cultures was observed with all drugs tested in vitro at concentrations of 5 mumol/L or higher. In contrast, there was a clear segregation of the in vivo effect on P berghei in rats (300 mg/kg/d subcutaneous) into two categories: compounds CP20, 38, and 40 failed to suppress malaria, whereas CP51, 94, and 96 had a strong antimalarial effect, similar or better than deferoxamine. There was a close linear correlation between the suppression of peak parasite counts and the reduction in hepatic nonheme iron induced by the various drugs tested (r = .9837). The most lipophilic compounds were also the most effective in suppressing malaria and in depleting hepatic iron stores. These data indicate that 3-hydroxypyrydin-4-ones are able to suppress malaria in vivo and in vitro. Because lipid solubility is an important determinant of antimalarial action, our study provides useful information regarding the selection of orally effective iron-chelating compounds that may be suitable for clinical application as antimalarial agents.

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Computational Chemogenomics Drug Repositioning Strategy Enables the Discovery of Epirubicin as a New Repurposed Hit for Plasmodium falciparum and P. vivax

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02041-19 ◽

2020 ◽

Vol 64 (9) ◽

Author(s):

Letícia Tiburcio Ferreira ◽

Juliana Rodrigues ◽

Gustavo Capatti Cassiano ◽

Tatyana Almeida Tavella ◽

Kaira Cristina Peralis Tomaz ◽

...

Keyword(s):

Plasmodium Falciparum ◽

In Silico ◽

Antimalarial Activity ◽

Drug Repositioning ◽

Dna Gyrase ◽

Plasmodium Yoelii ◽

Computer Assisted ◽

Content Type

ABSTRACT Widespread resistance against antimalarial drugs thwarts current efforts for controlling the disease and urges the discovery of new effective treatments. Drug repositioning is increasingly becoming an attractive strategy since it can reduce costs, risks, and time-to-market. Herein, we have used this strategy to identify novel antimalarial hits. We used a comparative in silico chemogenomics approach to select Plasmodium falciparum and Plasmodium vivax proteins as potential drug targets and analyzed them using a computer-assisted drug repositioning pipeline to identify approved drugs with potential antimalarial activity. Among the seven drugs identified as promising antimalarial candidates, the anthracycline epirubicin was selected for further experimental validation. Epirubicin was shown to be potent in vitro against sensitive and multidrug-resistant P. falciparum strains and P. vivax field isolates in the nanomolar range, as well as being effective against an in vivo murine model of Plasmodium yoelii. Transmission-blocking activity was observed for epirubicin in vitro and in vivo. Finally, using yeast-based haploinsufficiency chemical genomic profiling, we aimed to get insights into the mechanism of action of epirubicin. Beyond the target predicted in silico (a DNA gyrase in the apicoplast), functional assays suggested a GlcNac-1-P-transferase (GPT) enzyme as a potential target. Docking calculations predicted the binding mode of epirubicin with DNA gyrase and GPT proteins. Epirubicin is originally an antitumoral agent and presents associated toxicity. However, its antiplasmodial activity against not only P. falciparum but also P. vivax in different stages of the parasite life cycle supports the use of this drug as a scaffold for hit-to-lead optimization in malaria drug discovery.

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