scholarly journals Novel Antimalarial Aminoquinolines: Heme Binding and Effects on Normal or Plasmodium falciparum-Parasitized Human Erythrocytes

2009 ◽  
Vol 53 (10) ◽  
pp. 4339-4344 ◽  
Author(s):  
Fausta Omodeo-Salè ◽  
Lucia Cortelezzi ◽  
Nicoletta Basilico ◽  
Manolo Casagrande ◽  
Anna Sparatore ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Antimalarial Activity ◽  
Heme Binding ◽  
Human Red Blood Cells ◽  
Rbc Membrane ◽  
Alkyl Derivatives ◽  
Resistant Strains ◽  
Dose Dependent

ABSTRACT Two new quinolizidinyl-alkyl derivatives of 7-chloro-4-aminoquinoline, named AM-1 and AP4b, which are highly effective in vitro against both the D10 (chloroquine [CQ] susceptible) and W2 (CQ resistant) strains of Plasmodium falciparum and in vivo in the rodent malaria model, have been studied for their ability to bind to and be internalized by normal or parasitized human red blood cells (RBC) and for their effects on RBC membrane stability. In addition, an analysis of the heme binding properties of these compounds and of their ability to inhibit beta-hematin formation in vitro has been performed. Binding of AM1 or AP4b to RBC is rapid, dose dependent, and linearly related to RBC density. Their accumulation in parasitized RBC (pRBC) is increased twofold compared to levels in normal RBC. Binding of AM1 or AP4b to both normal and pRBC is higher than that of CQ, in agreement with the lower pKa and higher lipophilicity of the compounds. AM1 or AP4b is not hemolytic per se and is less hemolytic than CQ when hemolysis is accelerated (induced) by hematin. Moreover, AM-1 and AP4b bind heme with a stoichiometry of interaction similar to that of CQ (about 1:1.7) but with a lower affinity. They both inhibit dose dependently the formation of beta-hematin in vitro with a 50% inhibitory concentration comparable to that of CQ. Taken together, these results suggest that the antimalarial activity of AM1 or AP4b is likely due to inhibition of hemozoin formation and that the efficacy of these compounds against the CQ-resistant strains can be ascribed to their hydrophobicity and capacity to accumulate in the vacuolar lipid (elevated lipid accumulation ratios).

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

Blood ◽  
1990 ◽  
Vol 76 (6) ◽  
pp. 1250-1255 ◽  
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.

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

2009 ◽  
Vol 105 (1) ◽  
pp. 275-279 ◽  
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

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

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.

scholarly journals Antiplasmodial Quinones from the Rhizomes of Kniphofia Foliosa

2013 ◽  
Vol 8 (9) ◽  
pp. 1934578X1300800 ◽  
Author(s):  
Martha Induli ◽  
Meron Gebru ◽  
Negera Abdissa ◽  
Hosea Akala ◽  
Ingrid Wekesa ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Methyl Ether ◽  
Spectroscopic Data ◽  
Antimalarial Activity ◽  
In Vivo Assay

Extracts of the rhizomes of Kniphofia foliosa exhibited antiplasmodial activities against the chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum with IC50 values of 3–5 μg/mL. A phenyloxanthrone, named 10-acetonylknipholone cyclooxanthrone (1) and an anthraquinone-anthrone dimer, chryslandicin 10-methyl ether (2), were isolated from the rhizomes, along with known quinones, including the rare phenylanthraquinone dimers, joziknipholones A and B. The structures of these compounds were determined based on spectroscopic data. This is the second report on the occurrence of the dimeric phenylanthraquinones in nature. In an in vitro antiplasmodial assay of the isolated compounds, activity was observed for phenylanthraquinones, anthraquinone-anthrone dimers and dimeric phenylanthraquinones, with joziknipholone A being the most active. The new compound, 10-acetonylknipholone cyclooxanthrone, also showed anti-plasmodial activity. In an in vivo assay, knipholone anthrone displayed marginal antimalarial activity.

Antimalarial Activity of Phenazines from Lapachol, β-Lapachone and Its Derivatives Against Plasmodium falciparum in vitro and Plasmodium berghei in vivo.

ChemInform ◽  
2004 ◽  
Vol 35 (26) ◽  
Author(s):  
Valter F. de Andrade-Neto ◽  
Marilia O. F. Goulart ◽  
Jorge F. da Silva Filho ◽  
Matuzalem J. da Silva ◽  
Maria do Carmo F. R. Pinto ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Plasmodium Berghei ◽  
Antimalarial Activity

scholarly journals Synthesis and Antimalarial Activities of Cyclen 4-Aminoquinoline Analogs

2009 ◽  
Vol 53 (4) ◽  
pp. 1320-1324 ◽  
Author(s):  
M. O. Faruk Khan ◽  
Mark S. Levi ◽  
Babu L. Tekwani ◽  
Shabana I. Khan ◽  
Eiichi Kimura ◽  
...  
Keyword(s):  
Mammalian Cells ◽  
High Selectivity ◽  
Antimalarial Activity ◽  
New Class ◽  
Antimalarial Agents ◽  
Sensitive Clone ◽  
Resistant Strains ◽  
Incorporation Assay

ABSTRACT In an attempt to augment the efficacy of 7-chloro 4-aminoquinoline analogs and also to overcome resistance to antimalarial agents, we synthesized three cyclen (1,4,7,10-tetraazacyclododecane) analogs of chloroquine [a bisquinoline derivative, 7-chloro-4-(1,4,7,10-tetraaza-cyclododec-1-yl)-quinoline HBr, and a 7-chloro-4-(1,4,7,10-tetraaza-cyclododec-1-yl)-quinoline-Zn2+ complex]. The bisquinoline displays the most potent in vitro and in vivo antimalarial activities. It displays 50% inhibitory concentrations (IC50s) of 7.5 nM against the D6 (chloroquine-sensitive) clone of Plasmodium falciparum and 19.2 nM against the W2 (chloroquine-resistant) clone, which are comparable to those of artemisinin (10.6 and 5.0 nM, respectively) and lower than those of chloroquine (10.7 and 87.2 nM, respectively), without any evidence of cytotoxicity to mammalian cells, indicating a high selectivity index (>1,333 against D6 clone and >521 against W2 clone). Potent antimalarial activities of the bisquinoline against chloroquine- and mefloquine-resistant strains of P. falciparum were also confirmed by in vitro [3H]hypoxanthine incorporation assay. The in vivo antimalarial activity of the bisquinoline, as determined in P. berghei-infected mice, is comparable to that of chloroquine (50% effective dose, ≤1.1 mg/kg when given orally); no apparent toxicity has been observed up to the highest dose tested (3 × 30 mg/kg). The bisquinoline inhibits in vitro hemozoin (β-hematin) formation with an IC50 of 1.1 μM, which is about 10-fold more potent than chloroquine (IC50 9.5 μM). Overall, this article describes the discovery of a new class of cyclen 4-aminoquinoline analogs as potent antimalarial drugs.

scholarly journals Evaluation of in vitro and in vivo Antiplasmodial Activity of the Leaf Latex of Aloe Weloensis (Aloaceae)

2020 ◽  
Author(s):  
Gedefaw Getnet Amare ◽  
Tadesse Awgichew ◽  
Solomon Ahmed ◽  
Zemene Demelash Kifle
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Activities ◽  
Antimalarial Activity ◽  
Potential Effect ◽  
Pack Cell Volume ◽  
Curative Effect ◽  
Parasitemia Level ◽  
Dose Dependent

Abstract Background: Nature has gifted a variety of plants having potential effect against plasmodium parasites. The present study was aimed to determine in vitro and in vivo antimalarial activity of the leaf latex of Aloe weloensis.Methods: In vitro antimalarial activity of the leaf latex of A. weloensis was determined against 3D7 strain of P. falciparum. Antimalarial activity of the three doses the latex was evaluated in 4 day-suppressive and curative models against P. berghei infected mice. Antioxidant activity of the leaf latex of A. weloensis was assessed in 2,2- diphenyl 1- picrylhydrazine assay model. Results: Antioxidant activity of the latex was concentration dependent; the strongest inhibition was measured at 400 μg/mL (73.54%). The leaf latex of A. weloensis was demonstrated inhibitory activity against 3D7 malarial strain (IC50 = 9.14 μg/ml). Suppressive and curative effect of the latex was found to be dose dependent. Parasitemia reduction was significant (200 mg/kg, p<0.01, 400 and ,600 mg/kg, p<0.001) in 4-day suppressive test compared to vehicle control. Parasitemia level of the mice treated with 200, 400 and 600 mg/kg doses of the latex significantly (p<0.001) reduced with suppression of 36%, 58% and 64% respectively in curative test. Administration of the leaf latex of A. weloensis significantly (p<0.01) improved mean survival time, pack cell volume, rectal temperature and body weight of P. berghei infected mice. Conclusion: The finding showed that the leaf latex of Aloe weloensis endowed prominent antimalarial and antioxidant activities. The result can serve as a step towards the development of safe and effective herbal therapy against plasmodium parasites.

Hybrid molecules with potential in vitro antiplasmodial and in vivo antimalarial activity against drug‐resistant Plasmodium falciparum

2019 ◽  
Vol 40 (3) ◽  
pp. 931-971 ◽  
Author(s):  
Lian‐Shun Feng ◽  
Zhi Xu ◽  
Le Chang ◽  
Chuan Li ◽  
Xiao‐Fei Yan ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Antimalarial Activity ◽  
Drug Resistant ◽  
Hybrid Molecules

scholarly journals Andrographolide: A Novel Antimalarial Diterpene Lactone Compound fromAndrographis paniculataand Its Interaction with Curcumin and Artesunate

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Kirti Mishra ◽  
Aditya P. Dash ◽  
Nrisingha Dey
Keyword(s):  
Plasmodium Falciparum ◽  
Life Span ◽  
Plasmodium Berghei ◽  
Antimalarial Activity ◽  
Andrographis Paniculata ◽  
Antiplasmodial Activity ◽  
Template Molecule

Andrographolide (AND), the diterpene lactone compound, was purified by HPLC from the methanolic fraction of the plantAndrographis paniculata. The compound was found to have potent antiplasmodial activity when tested in isolation and in combination with curcumin and artesunate against the erythrocytic stages ofPlasmodium falciparum in vitroandPlasmodium bergheiANKAin vivo. IC50s for artesunate (AS), andrographolide (AND), and curcumin (CUR) were found to be 0.05, 9.1 and 17.4 μM, respectively. The compound (AND) was found synergistic with curcumin (CUR) and addictively interactive with artesunate (AS).In vivo, andrographolide-curcumin exhibited better antimalarial activity, not only by reducing parasitemia (29%), compared to the control (81%), but also by extending the life span by 2-3 folds. Being nontoxic to thein vivosystem this agent can be used as template molecule for designing new derivatives with improved antimalarial properties.

Sign in / Sign up

Export Citation Format

Share Document