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Dias BKM, Mohanty A, Garcia CRS. Melatonin as a Circadian Marker for Plasmodium Rhythms. Int J Mol Sci 2024; 25:7815. [PMID: 39063057 PMCID: PMC11277106 DOI: 10.3390/ijms25147815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Revised: 07/02/2024] [Accepted: 07/10/2024] [Indexed: 07/28/2024] Open
Abstract
Plasmodium, a digenetic parasite, requires a host and a vector for its life cycle completion. Most Plasmodium species display circadian rhythmicity during their intraerythrocytic cycle within the host, aiding in immune evasion. This rhythmicity, however, diminishes in in vitro cultures, highlighting the importance of host-derived signals for synchronizing the parasite's asexual cycle. Studies indicate a species-specific internal clock in Plasmodium, dependent on these host signals. Melatonin, a hormone the pineal gland produces under circadian regulation, impacts various physiological functions and is extensively reviewed as the primary circadian marker affecting parasite rhythms. Research suggests that melatonin facilitates synchronization through the PLC-IP3 signaling pathway, activating phospholipase C, which triggers intracellular calcium release and gene expression modulation. This evidence strongly supports the role of melatonin as a key circadian marker for parasite synchronization, presenting new possibilities for targeting the melatonin pathway when developing novel therapeutic approaches.
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Affiliation(s)
| | | | - Célia R. S. Garcia
- Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of Sao Paulo, Sao Paulo 05508-000, SP, Brazil; (B.K.M.D.); (A.M.)
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2
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Mogaka S, Mulei I, Njoki P, Ogila K, Waihenya R, Onditi F, Ozwara H. Antimalarial Efficacy and Safety of Senna occidentalis (L.) Link Root Extract in Plasmodium berghei-Infected BALB/c Mice. BIOMED RESEARCH INTERNATIONAL 2023; 2023:8296195. [PMID: 37583959 PMCID: PMC10425254 DOI: 10.1155/2023/8296195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 07/05/2023] [Accepted: 07/25/2023] [Indexed: 08/17/2023]
Abstract
Background Emergence of Plasmodium resistance to antimalarial drugs presents a major drawback in efforts to control malaria. To address this problem, there is an urgent and continuous need for the development of new and effective antimalarial agents. Senna occidentalis (L.) link extract has exhibited in vitro antiplasmodial activity in many pharmacological studies. To our knowledge, data on its in vivo antimalarial efficacy is still very limited. A recent study demonstrated that polar extracts from the plant roots inhibit Plasmodium berghei proliferation in a mouse model. This study further describes the efficacy and safety of a methanolic root extract of the plant as an antimalarial agent by demonstrating its effect on hematological, biochemical, and histological parameters of Plasmodium berghei-infected BALB/c mice. Methods Rane's test, a curative approach, was used to evaluate the antimalarial efficacy of Senna occidentalis methanolic root extract in Plasmodium berghei-infected BALB/c mice. The effect of the extract on both hematological and biochemical parameters was evaluated using automated analyzers. Kidney, liver, lung, spleen, and brain tissues were harvested from euthanized mice and examined for changes in organ architecture. Results This study demonstrates that methanolic root extract of Senna occidentalis significantly inhibited Plasmodium berghei parasitemia in BALB/c mice (p < 0.01). Infected mice that were treated with the extract depicted a significantly low level of total leucocytes (p < 0.01), red blood cell distribution width (p < 0.01), and a significantly high hemoglobin concentration (p < 0.001) compared to the infected animals that were administered with the vehicle only. The infected animals that were treated with the extract exhibited a significantly low level of urea, creatinine, bilirubin, and alkaline phosphatase (p < 0.05), compared to the infected animals that were given the vehicle only. The level of sodium, potassium and chloride ions, lymphocytes, granulocytes, hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration, total protein, albumin, aspartate aminotransferase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), total platelets, mean platelet volume (MPV), and platelet distribution width of the infected animals treated with the extract was not significantly different from those of the infected animals that were given the vehicle only (p > 0.05). The extract alleviated organ pathological changes in the infected mice. The extract did not induce any remarkable adverse effect on the growth, hematological, and biochemical parameters of uninfected animals (p > 0.05). In addition, administration of the extract did not alter the gross appearance and histological architecture of the organs, implying that the extract was well tolerated in mice. Conclusions Senna occidentalis methanolic root extract exhibited good antimalarial activity against Plasmodium berghei and may be safe in mice.
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Affiliation(s)
- Simeon Mogaka
- Department of Tropical and Infectious Diseases, Institute of Primate Research, P.O. Box 24481, Karen, 00502 Nairobi, Kenya
- Department of Zoology, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000-00200 Nairobi, Kenya
| | - Isaac Mulei
- Department of Veterinary Pathology, Microbiology and Parasitology, University of Nairobi, P.O. Box 29053, 00625 Nairobi, Kenya
| | - Peninah Njoki
- Department of Medical Science, Technical University of Mombasa, P.O. Box 90420-80100, Mombasa, Kenya
| | - Kenneth Ogila
- Department of Zoology, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000-00200 Nairobi, Kenya
| | - Rebecca Waihenya
- Department of Zoology, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000-00200 Nairobi, Kenya
| | - Faith Onditi
- Department of Tropical and Infectious Diseases, Institute of Primate Research, P.O. Box 24481, Karen, 00502 Nairobi, Kenya
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Hastings Ozwara
- Department of Tropical and Infectious Diseases, Institute of Primate Research, P.O. Box 24481, Karen, 00502 Nairobi, Kenya
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Motta FC, McGoff K, Moseley RC, Cho CY, Kelliher CM, Smith LM, Ortiz MS, Leman AR, Campione SA, Devos N, Chaorattanakawee S, Uthaimongkol N, Kuntawunginn W, Thongpiam C, Thamnurak C, Arsanok M, Wojnarski M, Vanchayangkul P, Boonyalai N, Smith PL, Spring MD, Jongsakul K, Chuang I, Harer J, Haase SB. The parasite intraerythrocytic cycle and human circadian cycle are coupled during malaria infection. Proc Natl Acad Sci U S A 2023; 120:e2216522120. [PMID: 37279274 PMCID: PMC10268210 DOI: 10.1073/pnas.2216522120] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 05/09/2023] [Indexed: 06/08/2023] Open
Abstract
During infections with the malaria parasites Plasmodium vivax, patients exhibit rhythmic fevers every 48 h. These fever cycles correspond with the time the parasites take to traverse the intraerythrocytic cycle (IEC). In other Plasmodium species that infect either humans or mice, the IEC is likely guided by a parasite-intrinsic clock [Rijo-Ferreiraet al., Science 368, 746-753 (2020); Smith et al., Science 368, 754-759 (2020)], suggesting that intrinsic clock mechanisms may be a fundamental feature of malaria parasites. Moreover, because Plasmodium cycle times are multiples of 24 h, the IECs may be coordinated with the host circadian clock(s). Such coordination could explain the synchronization of the parasite population in the host and enable alignment of IEC and circadian cycle phases. We utilized an ex vivo culture of whole blood from patients infected with P. vivax to examine the dynamics of the host circadian transcriptome and the parasite IEC transcriptome. Transcriptome dynamics revealed that the phases of the host circadian cycle and the parasite IEC are correlated across multiple patients, showing that the cycles are phase coupled. In mouse model systems, host-parasite cycle coupling appears to provide a selective advantage for the parasite. Thus, understanding how host and parasite cycles are coupled in humans could enable antimalarial therapies that disrupt this coupling.
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Affiliation(s)
- Francis C. Motta
- Department of Mathematical Sciences, Florida Atlantic University, Boca Raton, FL33431
| | - Kevin McGoff
- Department of Mathematics and Statistics, University of North Carolina, Charlotte, NC28223
| | | | - Chun-Yi Cho
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA94143
| | - Christina M. Kelliher
- Department of Molecular & Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH03755
| | | | | | | | | | | | - Suwanna Chaorattanakawee
- Department of Parasitology and Entomology, Faculty of Public Health, Mahidol University, Bangkok10400, Thailand
| | | | | | - Chadin Thongpiam
- US-Armed Forces Research Institute of Medical Sciences, Bangkok10400, Thailand
| | | | - Montri Arsanok
- US-Armed Forces Research Institute of Medical Sciences, Bangkok10400, Thailand
| | | | | | - Nonlawat Boonyalai
- US-Armed Forces Research Institute of Medical Sciences, Bangkok10400, Thailand
| | - Philip L. Smith
- U.S. Military HIV Research Program Walter Reed Army Institute of Research, Bethesda, MD20817
| | - Michele D. Spring
- US-Armed Forces Research Institute of Medical Sciences, Bangkok10400, Thailand
| | - Krisada Jongsakul
- US-Armed Forces Research Institute of Medical Sciences, Bangkok10400, Thailand
| | - Ilin Chuang
- US Naval Medical Research Center-Asia in Singapore, Assigned to Armed Forces Research Institute of Medical Sciences, Bangkok10400, Thailand
| | - John Harer
- Geometric Data Analytics, Durham, NC27701
| | - Steven B. Haase
- Department of Biology, Duke University, Durham, NC27708
- Department of Medicine Duke University, Durham, NC27710
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O'Donnell AJ, Greischar MA, Reece SE. Mistimed malaria parasites re-synchronize with host feeding-fasting rhythms by shortening the duration of intra-erythrocytic development. Parasite Immunol 2021; 44:e12898. [PMID: 34778983 PMCID: PMC9285586 DOI: 10.1111/pim.12898] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 11/08/2021] [Accepted: 11/09/2021] [Indexed: 12/24/2022]
Abstract
AIMS Malaria parasites exhibit daily rhythms in the intra-erythrocytic development cycle (IDC) that underpins asexual replication in the blood. The IDC schedule is aligned with the timing of host feeding-fasting rhythms. When the IDC schedule is perturbed to become mismatched to host rhythms, it readily reschedules but it is not known how. METHODS We intensively follow four groups of infections that have different temporal alignments between host rhythms and the IDC schedule for 10 days, before and after the peak in asexual densities. We compare how the duration, synchrony and timing of the IDC differs between parasites in control infections and those forced to reschedule by 12 hours and ask whether the density of parasites affects the rescheduling process. RESULTS AND CONCLUSIONS Our experiments reveal parasites shorten the IDC duration by 2-3 hours to become realigned to host feeding-fasting rhythms with 5-6 days, in a density-independent manner. Furthermore, parasites are able to reschedule without significant fitness costs for them or their hosts. Understanding the extent of, and limits on, plasticity in the IDC schedule may reveal targets for novel interventions, such as drugs to disrupt IDC regulation and preventing IDC dormancy conferring tolerance to existing drugs.
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Affiliation(s)
- Aidan J O'Donnell
- Institute of Evolutionary Biology, and Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Megan A Greischar
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York, USA
| | - Sarah E Reece
- Institute of Evolutionary Biology, and Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
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5
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Dos Santos BM, Pereira PH, Garcia CR. Molecular basis of synchronous replication of malaria parasites in the blood stage. Curr Opin Microbiol 2021; 63:210-215. [PMID: 34428626 DOI: 10.1016/j.mib.2021.08.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Revised: 08/02/2021] [Accepted: 08/04/2021] [Indexed: 10/20/2022]
Abstract
The search for host factors that leads to malaria parasite synchronization has been the focus of several laboratories. The host hormone melatonin synchronizes Plasmodium falciparum in culture by increasing the number of mature parasite stages through a PLC-IP3 activation. Melatonin signaling is linked to crosstalk between Ca2+-cAMP that results in PKA activation. Two other kinases, PfPK7 and PfeIK1, and the nuclear protein PfMORC that lacks melatonin sensitivity in the inducible knock-down parasites are also identified as part of the hormone-signal transduction pathways. Melatonin also modulates P. falciparum mitochondrial fission genes FIS1, DYN1, and DYN2 in a stage-specific manner. How these multiple molecular mechanisms are orchestrated to lead to parasite synchronization is a fascinating and opened biological question.
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Affiliation(s)
- Benedito M Dos Santos
- Laboratory of Functional Genomics and Antimalarial Discovery, Department of Clinical and Toxicological Analysis, School of Pharmaceutical Sciences, University of São Paulo, 05508-000, São Paulo, Brazil
| | - Pedro Hs Pereira
- Laboratory of Functional Genomics and Antimalarial Discovery, Department of Clinical and Toxicological Analysis, School of Pharmaceutical Sciences, University of São Paulo, 05508-000, São Paulo, Brazil
| | - Célia Rs Garcia
- Laboratory of Functional Genomics and Antimalarial Discovery, Department of Clinical and Toxicological Analysis, School of Pharmaceutical Sciences, University of São Paulo, 05508-000, São Paulo, Brazil.
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Prior KF, Rijo-Ferreira F, Assis PA, Hirako IC, Weaver DR, Gazzinelli RT, Reece SE. Periodic Parasites and Daily Host Rhythms. Cell Host Microbe 2020; 27:176-187. [PMID: 32053788 DOI: 10.1016/j.chom.2020.01.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Biological rhythms appear to be an elegant solution to the challenge of coordinating activities with the consequences of the Earth's daily and seasonal rotation. The genes and molecular mechanisms underpinning circadian clocks in multicellular organisms are well understood. In contrast, the regulatory mechanisms and fitness consequences of biological rhythms exhibited by parasites remain mysterious. Here, we explore how periodicity in parasite traits is generated and why daily rhythms matter for parasite fitness. We focus on malaria (Plasmodium) parasites which exhibit developmental rhythms during replication in the mammalian host's blood and in transmission to vectors. Rhythmic in-host parasite replication is responsible for eliciting inflammatory responses, the severity of disease symptoms, and fueling transmission, as well as conferring tolerance to anti-parasite drugs. Thus, understanding both how and why the timing and synchrony of parasites are connected to the daily rhythms of hosts and vectors may make treatment more effective and less toxic to hosts.
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Affiliation(s)
- Kimberley F Prior
- Institute of Evolutionary Biology & Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, UK.
| | - Filipa Rijo-Ferreira
- Department of Neuroscience, Peter O'Donnell Jr. Brain Institute & Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Patricia A Assis
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA
| | - Isabella C Hirako
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA; Laboratório de Imunopatologia, Fundação Oswaldo Cruz - Minas, Belo Horizonte, MG, Brazil
| | - David R Weaver
- Department of Neurobiology & NeuroNexus Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Ricardo T Gazzinelli
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA, USA; Laboratório de Imunopatologia, Fundação Oswaldo Cruz - Minas, Belo Horizonte, MG, Brazil
| | - Sarah E Reece
- Institute of Evolutionary Biology & Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, UK
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7
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Diallo AB, Coiffard B, Leone M, Mezouar S, Mege JL. For Whom the Clock Ticks: Clinical Chronobiology for Infectious Diseases. Front Immunol 2020; 11:1457. [PMID: 32733482 PMCID: PMC7363845 DOI: 10.3389/fimmu.2020.01457] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 06/04/2020] [Indexed: 12/20/2022] Open
Abstract
The host defense against pathogens varies among individuals. Among the factors influencing host response, those associated with circadian disruptions are emerging. These latter depend on molecular clocks, which control the two partners of host defense: microbes and immune system. There is some evidence that infections are closely related to circadian rhythms in terms of susceptibility, clinical presentation and severity. In this review, we overview what is known about circadian rhythms in infectious diseases and update the knowledge about circadian rhythms in immune system, pathogens and vectors. This heuristic approach opens a new fascinating field of time-based personalized treatment of infected patients.
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Affiliation(s)
- Aïssatou Bailo Diallo
- Aix-Marseille Univ, MEPHI, IRD, AP-HM, Marseille, France.,IHU-Méditerranée Infection, Marseille, France
| | - Benjamin Coiffard
- Aix-Marseille Univ, MEPHI, IRD, AP-HM, Marseille, France.,IHU-Méditerranée Infection, Marseille, France.,Aix-Marseille Univ, AP-HM, Hôpital Nord, Médecine Intensive-Réanimation, Marseille, France
| | - Marc Leone
- Aix-Marseille Univ, MEPHI, IRD, AP-HM, Marseille, France.,IHU-Méditerranée Infection, Marseille, France.,Aix-Marseille Univ, AP-HM, CHU Hôpital Nord, Service d'Anesthésie et de Réanimation, Marseille, France
| | - Soraya Mezouar
- Aix-Marseille Univ, MEPHI, IRD, AP-HM, Marseille, France.,IHU-Méditerranée Infection, Marseille, France
| | - Jean-Louis Mege
- Aix-Marseille Univ, MEPHI, IRD, AP-HM, Marseille, France.,IHU-Méditerranée Infection, Marseille, France.,AP-HM, UF Immunologie, Marseille, France
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8
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Malaria parasites regulate intra-erythrocytic development duration via serpentine receptor 10 to coordinate with host rhythms. Nat Commun 2020; 11:2763. [PMID: 32488076 PMCID: PMC7265539 DOI: 10.1038/s41467-020-16593-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Accepted: 05/04/2020] [Indexed: 01/23/2023] Open
Abstract
Malaria parasites complete their intra-erythrocytic developmental cycle (IDC) in multiples of 24 h suggesting a circadian basis, but the mechanism controlling this periodicity is unknown. Combining in vivo and in vitro approaches utilizing rodent and human malaria parasites, we reveal that: (i) 57% of Plasmodium chabaudi genes exhibit daily rhythms in transcription; (ii) 58% of these genes lose transcriptional rhythmicity when the IDC is out-of-synchrony with host rhythms; (iii) 6% of Plasmodium falciparum genes show 24 h rhythms in expression under free-running conditions; (iv) Serpentine receptor 10 (SR10) has a 24 h transcriptional rhythm and disrupting it in rodent malaria parasites shortens the IDC by 2-3 h; (v) Multiple processes including DNA replication, and the ubiquitin and proteasome pathways, are affected by loss of coordination with host rhythms and by disruption of SR10. Our results reveal malaria parasites are at least partly responsible for scheduling the IDC and coordinating their development with host daily rhythms. The mechanism underlying periodicity of Plasmodium’s intra-erythrocytic developmental cycle (IDC) is unclear. Here, Subudhi et al. show that serpentine receptor 10 (SR10) plays a role in regulating the schedule of the IDC in line with the timing of host daily rhythms.
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In Vivo Antiplasmodial Activity of Different Solvent Extracts of Myrianthus libericus Stem Bark and Its Constituents in Plasmodium berghei-Infected Mice. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2020; 2020:8703197. [PMID: 32382310 PMCID: PMC7191442 DOI: 10.1155/2020/8703197] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 03/22/2020] [Accepted: 03/31/2020] [Indexed: 11/17/2022]
Abstract
The emergence and resurgence of P. falciparum resistance to generations of antimalarial drugs have prompted the search for new, effective, and safe antimalarial agents. This study aimed at investigating the in vivo antiplasmodial activity of the 70% hydroethanolic extract and constituents of the stem bark of Myrianthus libericus based on its ethnomedicinal use as an antimalarial agent. The antiplasmodial activity was assessed in Swiss albino mice employing the 4-day suppressive and Rane's tests. MLB significantly (p < 0.0001) suppressed parasitaemia by 52.26%, 65.40%, and 77.11% at 50, 100, and 200 mg·kg−1 doses, respectively, in the 4-day suppressive test. In Rane's test, the highest parasitaemia suppression of 72.50% was recorded at a dose of 200 mg·kg−1 of the extract. Fractionation of the bioactive ethyl acetate fraction by solvent-solvent partitioning and column chromatography led to the isolation of friedelan-3-one and stigmasterol being reported for the first time from this species. The compounds demonstrated remarkable antiplasmodial activity by suppressing parasitaemia by 65–72% in the suppressive test and 61–70% in the curative test at doses of 10–30 mg·kg−1. Both the extract and the isolated compounds significantly prolonged the survival time of infected mice and averted the cardinal signs associated with P. berghei-induced malaria including weight loss, hypothermia, and haemolysis. The results obtained confirm the prospect of M. libericus as an important source of new antimalarial compounds and justifies its folkloric use as an antimalarial agent.
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Greischar MA, Reece SE, Savill NJ, Mideo N. The Challenge of Quantifying Synchrony in Malaria Parasites. Trends Parasitol 2019; 35:341-355. [PMID: 30952484 DOI: 10.1016/j.pt.2019.03.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 03/04/2019] [Accepted: 03/05/2019] [Indexed: 12/21/2022]
Abstract
Malaria infection is often accompanied by periodic fevers, triggered by synchronous cycles of parasite replication within the host. The degree of synchrony in parasite development influences the efficacy of drugs and immune defenses and is therefore relevant to host health and infectiousness. Synchrony is thought to vary over the course of infection and across different host-parasite genotype or species combinations, but the evolutionary significance - if any - of this diversity remains elusive. Standardized methods are lacking, but the most common metric for quantifying synchrony is the percentage of parasites in a particular developmental stage. We use a heuristic model to show that this metric is often unacceptably biased. Methodological challenges must be addressed to characterize diverse patterns of synchrony and their consequences for disease severity and spread.
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Affiliation(s)
- Megan A Greischar
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada.
| | - Sarah E Reece
- Institute of Evolutionary Biology and Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, UK
| | - Nicholas J Savill
- Institute of Evolutionary Biology and Institute of Immunology and Infection Research, University of Edinburgh, Edinburgh, UK
| | - Nicole Mideo
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada
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11
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Westwood ML, O'Donnell AJ, de Bekker C, Lively CM, Zuk M, Reece SE. The evolutionary ecology of circadian rhythms in infection. Nat Ecol Evol 2019; 3:552-560. [PMID: 30886375 PMCID: PMC7614806 DOI: 10.1038/s41559-019-0831-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 01/30/2019] [Indexed: 01/05/2023]
Abstract
Biological rhythms coordinate organisms' activities with daily rhythms in the environment. For parasites, this includes rhythms in both the external abiotic environment and the within-host biotic environment. Hosts exhibit rhythms in behaviours and physiologies, including immune responses, and parasites exhibit rhythms in traits underpinning virulence and transmission. Yet, the evolutionary and ecological drivers of rhythms in traits underpinning host defence and parasite offence are largely unknown. Here, we explore how hosts use rhythms to defend against infection, why parasites have rhythms and whether parasites can manipulate host clocks to their own ends. Harnessing host rhythms or disrupting parasite rhythms could be exploited for clinical benefit; we propose an interdisciplinary effort to drive this emerging field forward.
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Affiliation(s)
- Mary L Westwood
- Institute of Evolutionary Biology and Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, UK.
| | - Aidan J O'Donnell
- Institute of Evolutionary Biology and Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | | | - Curtis M Lively
- Department of Biology, Indiana University, Bloomington, IL, USA
| | - Marlene Zuk
- Department of Ecology, Evolution and Behavior, University of Minnesota, St. Paul, MN, USA
| | - Sarah E Reece
- Institute of Evolutionary Biology and Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
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