1
|
Lawal B, Kuo YC, Rachmawati Sumitra M, Wu ATH, Huang HS. Identification of a novel immune-inflammatory signature of COVID-19 infections, and evaluation of pharmacokinetics and therapeutic potential of RXn-02, a novel small-molecule derivative of quinolone. Comput Biol Med 2022; 148:105814. [PMID: 35841781 PMCID: PMC9272679 DOI: 10.1016/j.compbiomed.2022.105814] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 06/07/2022] [Accepted: 07/03/2022] [Indexed: 01/18/2023]
Abstract
Coronavirus disease 2019 (COVID-19) is a global pandemic and respiratory infection that has enormous damage to human lives and economies. It is caused by SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), a non-pair-stranded positive-sense RNA virus. With increasing global threats and few therapeutic options, the discovery of new potential drug targets and the development of new therapy candidates against COVID-19 are urgently needed. Based on these premises, we conducted an analysis of transcriptomic datasets from SARS-CoV-2-infected patients and identified several SARS-CoV-2 infection signatures, among which TNFRSF5/PTPRC/IDO1/MKI67 appeared to be the most pertinent signature. Subsequent integrated bioinformatics analysis identified the signature as an important immunomodulatory and inflammatory signature of SARS-CoV-2 infection. It was suggested that this gene signature mediates the interplay of immune and immunosuppressive cells leading to infiltration-exclusion of effector memory T cells in the lungs, which is of translation relevance for developing novel SARS-CoV-2 drug and vaccine candidates. Consequently, we designed and synthesized a novel small-molecule quinoline derivative (RXn-02) and evaluated its pharmacokinetics in rats, revealing a peak plasma concentration (Cmax) and time to Cmax (Tmax) of 1.756 μg/mL and 0.6 h, respectively. Values of the area under the curve (AUC) (0–24 h) and AUC (0 h∼∞) were 18.90 and 71.20 μg h/mL, respectively. Drug absorption from the various regional segments revealed that the duodenum (49.84%), jejunum (47.885%), cecum (1.82%), and ileum (0.32%) were prime sites of RXn-02 absorption. No absorption was detected from the stomach, and the least was from the colon (0.19%). Interestingly, RXn-02 exhibited in vitro antiproliferative activities against hub gene hyper-expressing cell lines; A549 (IC50 = 48.1 μM), K-562 (IC50 = 100 μM), and MCF7 (IC50 = 0.047 μM) and against five cell lines originating from human lungs (IC50 range of 33.2–69.5 μM). In addition, RXn-02 exhibited high binding efficacies for targeting the TNFRSF5/PTPRC/IDO1/MK signature with binding affinities (ΔG) of −6.6, −6.0, −9.9, −6.9 kcal/mol respectively. In conclusion, our study identified a novel signature of SARS-CoV-2 pathogenesis. RXn-02 is a drug-like candidate with good in vivo pharmacokinetics and hence possesses great translational relevance worthy of further preclinical and clinical investigations for treating SARS-CoV-2 infections.
Collapse
Affiliation(s)
- Bashir Lawal
- PhD Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei 11031, Taiwan; Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 11031, Taiwan
| | - Yu-Cheng Kuo
- Department of Pharmacology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, 11031, Taiwan; School of Post-baccalaureate Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, 40402, Taiwan
| | - Maryam Rachmawati Sumitra
- PhD Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei 11031, Taiwan; Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 11031, Taiwan
| | - Alexander T H Wu
- The PhD Program of Translational Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei 11031, Taiwan; Clinical Research Center, Taipei Medical University Hospital, Taipei Medical University, Taipei, 11031, Taiwan; TMU Research Center of Cancer Translational Medicine, Taipei Medical University, Taipei, 11031, Taiwan; Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei 11490, Taiwan.
| | - Hsu-Shan Huang
- PhD Program for Cancer Molecular Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University and Academia Sinica, Taipei 11031, Taiwan; Graduate Institute of Cancer Biology and Drug Discovery, College of Medical Science and Technology, Taipei Medical University, Taipei 11031, Taiwan; Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei 11490, Taiwan; School of Pharmacy, National Defense Medical Center, Taipei, 11490, Taiwan; PhD Program in Drug Discovery and Development Industry, College of Pharmacy, Taipei Medical University, Taipei 11031, Taiwan.
| |
Collapse
|
2
|
Egwu CO, Tsamesidis I, Pério P, Augereau JM, Benoit-Vical F, Reybier K. Superoxide: A major role in the mechanism of action of essential antimalarial drugs. Free Radic Biol Med 2021; 167:271-275. [PMID: 33722628 DOI: 10.1016/j.freeradbiomed.2021.03.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 02/28/2021] [Accepted: 03/01/2021] [Indexed: 11/19/2022]
Abstract
Understanding the mode of action of antimalarials is central to optimizing their use and the discovery of new therapeutics. Currently used antimalarials belong to a limited series of chemical structures and their mechanisms of action are coutinuously debated. Whereas the involvement of reactive species that in turn kill the parasites sensitive to oxidative stress, is accepted for artemisinins, little is known about the generation of such species in the case of quinolines or hydroxynaphtoquinone. Moreover, the nature of the reactive species involved has never been characterized in Plasmodium-infected erythrocytes. The aim of this work was to determine and elucidate the production of the primary radical, superoxide in Plasmodium-infected erythrocytes treated with artemisinin, dihydroartemisinin, chloroquine and atovaquone, as representatives of three major classes of antimalarials. The intracellular generation of superoxide was quantified by liquid chromatography coupled to mass spectrometry (LC-MS). We demonstrated that artemisinins, atovaquone and to a lesser extent chloroquine, generate significant levels of superoxide radicals in Plasmodium falciparum sensitive strains. More so, the production of superoxide was lowered in chloroquine-resistant strain of Plasmodium treated with chloroquine. These results consolidate the knowledge about the mechanism of action of these different antimalarials and should be taken into consideration in the design of future drugs to fight drug-resistant parasites.
Collapse
Affiliation(s)
- Chinedu O Egwu
- PharmaDev, UMR 152, Université de Toulouse, IRD, UPS, Toulouse, France; Medical Biochemistry, College of Medicine, Alex-Ekwueme Federal University, Ndufu-Alike Ikwo, P.M.B. 1010, Abakaliki, Ebonyi State, Nigeria; CNRS, LCC, Laboratoire de Chimie de Coordination, Université de Toulouse, Toulouse, France; Institut de Pharmacologie et de Biologie Structurale, IPBS, Université de Toulouse, CNRS, UPS, France; New Antimalarial Molecules and Pharmacological Approaches, Inserm ERL 1289, Toulouse, France
| | | | - Pierre Pério
- PharmaDev, UMR 152, Université de Toulouse, IRD, UPS, Toulouse, France
| | - Jean-Michel Augereau
- CNRS, LCC, Laboratoire de Chimie de Coordination, Université de Toulouse, Toulouse, France; Institut de Pharmacologie et de Biologie Structurale, IPBS, Université de Toulouse, CNRS, UPS, France; New Antimalarial Molecules and Pharmacological Approaches, Inserm ERL 1289, Toulouse, France
| | - Françoise Benoit-Vical
- CNRS, LCC, Laboratoire de Chimie de Coordination, Université de Toulouse, Toulouse, France; Institut de Pharmacologie et de Biologie Structurale, IPBS, Université de Toulouse, CNRS, UPS, France; New Antimalarial Molecules and Pharmacological Approaches, Inserm ERL 1289, Toulouse, France.
| | - Karine Reybier
- PharmaDev, UMR 152, Université de Toulouse, IRD, UPS, Toulouse, France.
| |
Collapse
|
3
|
Arenas-Del Ángel M, Legorreta-Herrera M, Mendoza-Hernández G, Garfias Y, Chávez R, Zenteno E, Lascurain R. Amaranthus leucocarpus lectin recognizes a moesin-like O-glycoprotein and costimulates murine CD3-activated CD4(+) T cells. IMMUNITY INFLAMMATION AND DISEASE 2015; 3:182-95. [PMID: 26417436 PMCID: PMC4578519 DOI: 10.1002/iid3.58] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 03/16/2015] [Accepted: 03/18/2015] [Indexed: 11/22/2022]
Abstract
The Galβ1,3GalNAcα1,O-Ser/Thr specific lectin from Amaranthus leucocarpus (ALL) binds a ∼70 kDa glycoprotein on murine T cell surface. We show that in the absence of antigen presenting cells, murine CD4+ T cells activated by an anti-CD3 antibody plus ALL enhanced cell proliferation similar to those cells activated via CD3/CD28 at 48 h of culture. Moreover, ALL induced the production of IL-4, IL-10, TNF-alpha, and TGF-beta in CD3-activated cells. Proteomic assay using two-dimensional electrophoresis and far-Western blotting, ALL recognized two prominent proteins associated to the lipid raft microdomains in CD3/CD28-activated CD4+ T cells. By mass spectrometry, the peptide fragments from ALL-recognized proteins showed sequences with 33% homology to matricin (gi|347839 NCBInr) and 41% identity to an unnamed protein related to moesin (gi|74186081 NCBInr). Confocal microscopy analysis of CD3/CD28-activated CD4+ T cells confirmed that staining by ALL colocalized with anti-moesin FERM domain antibody along the plasma membrane and in the intercellular contact sites. Our findings suggest that a moesin-like O-glycoprotein is the ALL-recognized molecule in lipid rats, which induces costimulatory signals on CD4+ T cells.
Collapse
Affiliation(s)
- Maria Arenas-Del Ángel
- Departamento de Bioquimica, Facultad de Medicina Universidad Nacional Autónoma de México
| | - Martha Legorreta-Herrera
- Laboratorio de Inmunologia Molecular, Facultad de Estudios Superiores Zaragoza Universidad Nacional Autónoma de México
| | | | - Yonathan Garfias
- Departamento de Bioquimica, Facultad de Medicina Universidad Nacional Autónoma de México ; Unidad de Investigación Instituto de Oftalmologia "Fundación Conde de Valenciana"
| | - Raul Chávez
- Departamento de Bioquimica, Facultad de Medicina Universidad Nacional Autónoma de México
| | - Edgar Zenteno
- Departamento de Bioquimica, Facultad de Medicina Universidad Nacional Autónoma de México
| | - Ricardo Lascurain
- Departamento de Bioquimica, Facultad de Medicina Universidad Nacional Autónoma de México ; Departamento de Investigación en Bioquimica Instituto Nacional de Enfermedades Respiratorias "Ismael Cosio Villegas", México
| |
Collapse
|
4
|
Dalhoff A. Antiviral, antifungal, and antiparasitic activities of fluoroquinolones optimized for treatment of bacterial infections: a puzzling paradox or a logical consequence of their mode of action? Eur J Clin Microbiol Infect Dis 2015; 34:661-8. [PMID: 25515946 PMCID: PMC7087824 DOI: 10.1007/s10096-014-2296-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 12/02/2014] [Indexed: 12/19/2022]
Abstract
This review summarizes evidence that commercially available fluoroquinolones used for the treatment of bacterial infections are active against other non-bacterial infectious agents as well. Any of these fluoroquinolones exerts, in parallel to its antibacterial action, antiviral, antifungal, and antiparasitic actions at clinically achievable concentrations. This broad range of anti-infective activities is due to one common mode of action, i.e., the inhibition of type II topoisomerases or inhibition of viral helicases, thus maintaining the selective toxicity of fluoroquinolones inhibiting microbial topoisomerases at low concentrations but mammalian topoisomerases at much higher concentrations. Evidence suggests that standard doses of the fluoroquinolones studied are clinically effective against viral and parasitic infections, whereas higher doses administered topically were active against Candida spp. causing ophthalmological infections. Well-designed clinical studies should be performed to substantiate these findings.
Collapse
Affiliation(s)
- A Dalhoff
- Institute for Infection Medicine, University Medical Center Schleswig-Holstein, Brunswiker Str. 4, 24105, Kiel, Germany,
| |
Collapse
|
5
|
Gonadal steroids negatively modulate oxidative stress in CBA/Ca female mice infected with P. berghei ANKA. BIOMED RESEARCH INTERNATIONAL 2014; 2014:805495. [PMID: 25243182 PMCID: PMC4163401 DOI: 10.1155/2014/805495] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 07/24/2014] [Indexed: 12/25/2022]
Abstract
We decreased the level of gonadal steroids in female and male mice by gonadectomy. We infected these mice with P. berghei ANKA and observed the subsequent impact on the oxidative stress response. Intact females developed lower levels of parasitaemia and lost weight faster than intact males. Gonadectomised female mice displayed increased levels of parasitaemia, increased body mass, and increased anaemia compared with their male counterparts. In addition, gonadectomised females exhibited lower specific catalase, superoxide dismutase, and glutathione peroxidase activities in their blood and spleen tissues compared with gonadectomised males. To further study the oxidative stress response in P. berghei ANKA-infected gonadectomised mice, nitric oxide levels were assessed in the blood and spleen, and MDA levels were assessed in the spleen. Intact, sham-operated, and gonadectomised female mice exhibited higher levels of nitric oxide in the blood and spleen compared with male mice. MDA levels were higher in all of the female groups. Finally, gonadectomy significantly increased the oxidative stress levels in females but not in males. These data suggest that differential oxidative stress is influenced by oestrogens that may contribute to sexual dimorphism in malaria.
Collapse
|
6
|
Guiguemde WA, Hunt NH, Guo J, Marciano A, Haynes RK, Clark J, Guy RK, Golenser J. Treatment of murine cerebral malaria by artemisone in combination with conventional antimalarial drugs: antiplasmodial effects and immune responses. Antimicrob Agents Chemother 2014; 58:4745-54. [PMID: 24913162 PMCID: PMC4135990 DOI: 10.1128/aac.01553-13] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 05/27/2014] [Indexed: 01/10/2023] Open
Abstract
The decreasing effectiveness of antimalarial therapy due to drug resistance necessitates constant efforts to develop new drugs. Artemisinin derivatives are the most recent drugs that have been introduced and are considered the first line of treatment, but there are already indications of Plasmodium falciparum resistance to artemisinins. Consequently, drug combinations are recommended for prevention of the induction of resistance. The research here demonstrates the effects of novel combinations of the new artemisinin derivative, artemisone, a recently described 10-alkylamino artemisinin derivative with improved antimalarial activity and reduced neurotoxicity. We here investigate its ability to kill P. falciparum in a high-throughput in vitro assay and to protect mice against lethal cerebral malaria caused by Plasmodium berghei ANKA when used alone or in combination with established antimalarial drugs. Artemisone effects against P. falciparum in vitro were synergistic with halofantrine and mefloquine, and additive with 25 other drugs, including chloroquine and doxycycline. The concentrations of artemisone combinations that were toxic against THP-1 cells in vitro were much higher than their effective antimalarial concentration. Artemisone, mefloquine, chloroquine, or piperaquine given individually mostly protected mice against cerebral malaria caused by P. berghei ANKA but did not prevent parasite recrudescence. Combinations of artemisone with any of the other three drugs did completely cure most mice of malaria. The combination of artemisone and chloroquine decreased the ratio of proinflammatory (gamma interferon, tumor necrosis factor) to anti-inflammatory (interleukin 10 [IL-10], IL-4) cytokines in the plasma of P. berghei-infected mice. Thus, artemisone in combinations with other antimalarial drugs might have a dual action, both killing parasites and limiting the potentially deleterious host inflammatory response.
Collapse
Affiliation(s)
- W Armand Guiguemde
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Nicholas H Hunt
- Department of Pathology and Bosch Institute, The University of Sydney, Sydney, Australia
| | - Jintao Guo
- Department of Pathology and Bosch Institute, The University of Sydney, Sydney, Australia
| | - Annael Marciano
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Richard K Haynes
- Centre of Excellence for Pharmaceutical Sciences, North-West University, Potchefstroom, South Africa
| | - Julie Clark
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - R Kiplin Guy
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Jacob Golenser
- Department of Pathology and Bosch Institute, The University of Sydney, Sydney, Australia Department of Microbiology and Molecular Genetics, The Kuvin Center for the Study of Infectious and Tropical Diseases, The Hebrew University of Jerusalem, Jerusalem, Israel
| |
Collapse
|
7
|
Lozano JM, Guerrero YA, Alba MP, Lesmes LP, Escobar JO, Patarroyo ME. Redefining an epitope of a malaria vaccine candidate, with antibodies against the N-terminal MSA-2 antigen of Plasmodium harboring non-natural peptide bonds. Amino Acids 2013; 45:913-35. [PMID: 23836419 PMCID: PMC3776258 DOI: 10.1007/s00726-013-1541-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2012] [Accepted: 06/20/2013] [Indexed: 11/10/2022]
Abstract
The aim of obtaining novel vaccine candidates against malaria and other transmissible diseases can be partly based on selecting non-polymorphic peptides from relevant antigens of pathogens, which have to be then precisely modified for inducing a protective immunity against the disease. Bearing in mind the high degree of the MSA-221–40 peptide primary structure’s genetic conservation among malaria species, and its crucial role in the high RBC binding ability of Plasmodium falciparum (the main agent causing malaria), structurally defined probes based on non-natural peptide-bond isosteres were thus designed. Thus, two peptide mimetics were obtained (so-called reduced amide pseudopeptides), in which naturally made amide bonds of the 30FIN32-binding motif of MSA-2 were replaced with ψ–[CH2–NH] methylene amide isostere bonds, one between the F–I and the second between I–N amino acid pairs, respectively, coded as ψ-128 ψ-130. These peptide mimetics were used to produce poly- and monoclonal antibodies in Aotus monkeys and BALB/c mice. Parent reactive mice-derived IgM isotype cell clones were induced to Ig isotype switching to IgG sub-classes by controlled in vitro immunization experiments. These mature isotype immunoglobulins revealed a novel epitope in the MSA-225–32 antigen and two polypeptides of rodent malaria species. Also, these antibodies’ functional activity against malaria was tested by in vitro assays, demonstrating high efficacy in controlling infection and evidencing neutralizing capacity for the rodent in vivo malaria infection. The neutralizing effect of antibodies induced by site-directed designed peptide mimetics on Plasmodium’s biological development make these pseudopeptides a valuable tool for future development of immunoprophylactic strategies for controlling malarial infection.
Collapse
Affiliation(s)
- José Manuel Lozano
- Biocatalysis Department, Fundación Instituto de Inmunología de Colombia (FIDIC), Universidad del Rosario, Carrera 50 No. 26-20, 020304, Bogotá DC, Colombia,
| | | | | | | | | | | |
Collapse
|
8
|
Legorreta-Herrera M, Rivas-Contreras S, Ventura-Gallegos J, Zentella-Dehesa A. Nitric oxide is involved in the upregulation of IFN-γ and IL-10 mRNA expression by CD8⁺ T cells during the blood stages of P. chabaudi AS infection in CBA/Ca mice. Int J Biol Sci 2011; 7:1401-11. [PMID: 22110391 PMCID: PMC3221947 DOI: 10.7150/ijbs.7.1401] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 10/01/2011] [Indexed: 01/17/2023] Open
Abstract
Nitric oxide (NO) is involved in the clearance of several types of bacteria, viruses and parasites. Although the roles of NO and CD8+ T cells in the immune response to malaria have been extensively studied, their actual contributions during the blood stages of malaria infection remain unclear. In this work, we corroborate that serum NO levels are not associated with the in vivo elimination of the blood stages of Plasmodium chabaudi AS. In addition, we show that CD8+ T cells exhibit increased apoptosis and up regulate the expression of TNF-α mRNA on day 4 post-infection and IFN-γ and IL-10 mRNA on day 11 post-infection. Interestingly, only the levels of IFN-γ and IL-10 expression are affected when iNOS is inhibited with aminoguanidine (AG), suggesting that NO could be involved in the activation of CD8+ T cells during the blood stages of plasmodium infection.
Collapse
Affiliation(s)
- M Legorreta-Herrera
- Laboratorio de Inmunología Molecular, Facultad de Estudios Superiores Zaragoza, Universidad Nacional Autónoma de México, Batalla 5 de Mayo Esq. Fuerte de Loreto, Iztapalapa 09230, México, D.F. México.
| | | | | | | |
Collapse
|
9
|
Moneriz C, Marín-García P, Bautista JM, Diez A, Puyet A. Parasitostatic effect of maslinic acid. II. Survival increase and immune protection in lethal Plasmodium yoelii-infected mice. Malar J 2011; 10:103. [PMID: 21518429 PMCID: PMC3107817 DOI: 10.1186/1475-2875-10-103] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2011] [Accepted: 04/25/2011] [Indexed: 12/05/2022] Open
Abstract
Background The anti-malarial activity of maslinic acid (MA), a natural triterpene which has been previously shown to exert a parasitostatic action on Plasmodium falciparum cultures, was analysed in vivo by using the Plasmodium yoelii 17XL murine model. Methods ICR mice were infected with P. yoelii and treated with a single dose of MA by a intraperitoneal injection of MA (40 mg kg-1 day-1) followed by identical dose administration for the following three days. Parasitaemia and accumulation of intraerythrocytic stages was monitored microscopically. To assess protective immunity, cured mice were challenged with the same dose of parasites 40 days after recovery from the primary infection and parasitaemia was further monitored for 30 days. Humoral response was tested by ELISA and visualization of specific anti-P. yoelii antibodies was performed by Western-blotting. Results ICR mice treated with MA increased the survival rate from 20% to 80%, showing an arrest of parasite maturation from day 3 to 7 after infection and leading to synchronization of the intraerythrocytic cycle and accumulation of schizonts by day 6, proving that MA also behaves as a parasitostatic agent in vivo. Mice which survived the primary infection displayed lower rates of parasitic growth, showing a decline of parasitaemia after day 15, and complete clearance at day 20. These mice remained immunoprotected, showing not malaria symptoms or detectable parasitaemia after rechallenge with the same lethal strain. The analysis of specific antibodies against P. yoelii, present in mice which survived the infection, showed a significant increase in the number and intensity of immunoreactive proteins, suggesting that the protected mice may trigger a strong humoral response. Conclusion The survival increase observed in MA-treated mice can be explained considering that the parasitostatic effect exerted by this compound during the first days of infection increases the chances to develop effective innate and/or acquired immune responses. MA may represent a new class of anti-malarial compounds which, as a consequence of its parasitostatic action, favours the development of more effective sterilizing immune responses.
Collapse
Affiliation(s)
- Carlos Moneriz
- Departamento de Bioquímica y Biología Molecular IV, Universidad Complutense de Madrid, Facultad de Veterinaria, E28040 Madrid, Spain
| | | | | | | | | |
Collapse
|
10
|
Pyrimethamine induces oxidative stress in Plasmodium yoelii 17XL-infected mice: A novel immunomodulatory mechanism of action for an old antimalarial drug? Exp Parasitol 2010; 126:381-8. [DOI: 10.1016/j.exppara.2010.02.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Revised: 02/17/2010] [Accepted: 02/23/2010] [Indexed: 01/24/2023]
|
11
|
Scholzen A, Minigo G, Plebanski M. Heroes or villains? T regulatory cells in malaria infection. Trends Parasitol 2010; 26:16-25. [DOI: 10.1016/j.pt.2009.10.004] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Revised: 10/09/2009] [Accepted: 10/15/2009] [Indexed: 12/14/2022]
|
12
|
Delaleu N, Peck AB. Autoimmunity: limited progress for the patient, despite decades of research. Scand J Immunol 2009; 70:411-4. [DOI: 10.1111/j.1365-3083.2009.02318.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
|
13
|
Brouwers J, Vermeire K, Schols D, Augustijns P. Development and in vitro evaluation of chloroquine gels as microbicides against HIV-1 infection. Virology 2008; 378:306-10. [PMID: 18606432 PMCID: PMC7126913 DOI: 10.1016/j.virol.2008.06.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2008] [Revised: 05/07/2008] [Accepted: 06/05/2008] [Indexed: 02/06/2023]
Abstract
The potential success of a microbicide candidate in resource-poor countries will depend to a large extent on its availability and cost. Chloroquine is an inexpensive antimalarial drug that also exerts anti-HIV activity. The purpose of this study was to develop and characterize a vaginal formulation for chloroquine with preservation of its anti-HIV-1 activity. Gels containing the nonionic polymer hydroxyethyl cellulose were loaded with concentrations of the diphosphate salt of chloroquine (0.3–30 mg/g), that were 102- to 104-fold higher than typical in vitro anti-HIV-1 IC50-values of chloroquine (ca. 6 μg/ml). The gels were clear and homogeneous and displayed an osmolality of 300 mOsm/kg, a pH of 4.6 and a viscosity of 1.4 Pa s. Gel characteristics were preserved for at least 3 months at 40 °C and 75% relative humidity. Importantly, the chloroquine gels exerted a dose-dependent anti-HIV-1 activity in vitro (mean IC50 from 23 to 0.4 mg gel/ml) and the intrinsic activity of chloroquine was not affected by formulation factors. The in vitro efficacy of the chloroquine gel formulations warrants further testing of this drug as an anti-HIV-1 microbicide candidate.
Collapse
Affiliation(s)
- Joachim Brouwers
- Laboratory for Pharmacotechnology and Biopharmacy, Katholieke Universiteit Leuven, Leuven, Belgium.
| | | | | | | |
Collapse
|