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1.
Mem Inst Oswaldo Cruz ; 117: e220184, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36700582

RESUMO

BACKGROUND: Cerebral malaria is a lethal complication of Plasmodium falciparum infections in need of better therapies. Previous work in murine experimental cerebral malaria (ECM) indicated that the combination of artemether plus intraperitoneal whole blood improved vascular integrity and increased survival compared to artemether alone. However, the effects of blood or plasma transfusion administered via the intravenous route have not previously been evaluated in ECM. OBJECTIVES: To evaluate the effects of intravenous whole blood compared to intravenous plasma on hematological parameters, vascular integrity, and survival in artemether-treated ECM. METHODS: Mice with late-stage ECM received artemether alone or in combination with whole blood or plasma administered via the jugular vein. The outcome measures were hematocrit and platelets; plasma angiopoietin 1, angiopoietin 2, and haptoglobin; blood-brain barrier permeability; and survival. FINDINGS: Survival increased from 54% with artemether alone to 90% with the combination of artemether and intravenous whole blood. Intravenous plasma lowered survival to 18%. Intravenous transfusion provided fast and pronounced recoveries of hematocrit, platelets, angiopoietins levels and blood brain barrier integrity. MAIN CONCLUSIONS: The outcome of artemether-treated ECM was improved by intravenous whole blood but worsened by intravenous plasma. Compared to prior studies of transfusion via the intraperitoneal route, intravenous administration was more efficacious.


Assuntos
Antimaláricos , Artemisininas , Malária Cerebral , Malária Falciparum , Animais , Camundongos , Malária Cerebral/complicações , Malária Cerebral/tratamento farmacológico , Antimaláricos/uso terapêutico , Transfusão de Componentes Sanguíneos , Plasma , Artemeter/uso terapêutico , Malária Falciparum/tratamento farmacológico , Administração Intravenosa
2.
Org Lett ; 25(1): 277-281, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36592432

RESUMO

The site-selective functionalization of unactivated allylic C-H bonds via direct deprotonation using KTMP is described. The conversion of amorphadiene to artemisinic alcohol via a simple, highly regioselective deprotonation over 4 other possible allylic sites is shown with further extrapolation to the first large-scale telescoped chemical synthesis of artemisinic acid from amorphadiene. Finally, application of the method for the successful site-selective functionalization of unactivated allylic C-H bonds in other terpene-based natural products is also highlighted.


Assuntos
Artemisininas , Sesquiterpenos Policíclicos
3.
Sci Rep ; 13(1): 399, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36624300

RESUMO

Artemisinin combination therapies (ACTs) have led to a significant decrease in Plasmodium falciparum malaria mortality. This progress is now threatened by emerging artemisinin resistance (ART-R) linked originally in SE Asia to polymorphisms in the Kelch propeller protein (K13) and more recently to several other seemingly unrelated genetic mutations. To better understand the parasite response to ART, we are characterizing a P. falciparum mutant with altered sensitivity to ART that was created via piggyBac transposon mutagenesis. The transposon inserted near the putative transcription start site of a gene defined as a "Plasmodium-conserved gene of unknown function," now functionally linked to K13 as the Kelch13 Interacting Candidate 5 protein (KIC5). Phenotype analysis of the KIC5 mutant during intraerythrocytic asexual development identified transcriptional changes associated with DNA stress response and altered mitochondrial metabolism, linking dysregulation of the KIC5 gene to the parasite's ability to respond to ART exposure. Through characterization of the KIC5 transcriptome, we hypothesize that this gene may be essential under ART exposure to manage gene expression of the wild-type stress response at early ring stage, thereby providing a better understanding of the parasite's processes that can alter ART sensitivity.


Assuntos
Antimaláricos , Artemisininas , Plasmodium falciparum , Antimaláricos/farmacologia , Artemisininas/uso terapêutico , Resistência a Medicamentos/genética , Mutação , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo
4.
Commun Biol ; 6(1): 52, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36646927

RESUMO

Dihydroartemisinin (DHA), a potent antimalarial drug, also exhibits distinct property in modulation on Treg and B cells, which has been recognized for decades, but the underlying mechanisms remain understood. Herein we revealed that DHA could promote Treg proliferation, meanwhile, suppress B cell expansion in germinal centers, and consequently decrease the number of circulating plasma cells and the content of serum immunoglobulins. Further, DHA-activated Treg significantly mitigated lipopolysaccharide-induced and malaria-associated inflammation. All these scenarios were attributed to the upregulation of c-Fos expression by DHA and enhancement of its interaction with target genes in both Treg and circulating plasma cells with bilateral cell fates. In Treg, the c-Fos-DHA complex upregulated cell proliferation-associated genes and promoted cell expansion; whereas in plasma cells, it upregulated the apoptosis-related genes resulting in decreased circulating plasma cells. Thus, the bilateral immunoregulatory mechanism of DHA was elucidated and its application in the treatment of autoimmune diseases is further justified.


Assuntos
Antimaláricos , Artemisininas , Plasmócitos , Linfócitos T Reguladores , Artemisininas/farmacologia , Antimaláricos/farmacologia , Proteínas Proto-Oncogênicas c-fos/genética
5.
Malar J ; 22(1): 9, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36611179

RESUMO

BACKGROUND: In 2004, Ethiopia adopted artemether-lumefantrine (AL, Coartem®) as first-line treatment for the management of uncomplicated Plasmodium falciparum malaria. Continuous monitoring of AL therapeutic efficacy is crucial in Ethiopia, as per the World Health Organization (WHO) recommendation. This study aimed to assess the therapeutic efficacy of AL in the treatment of uncomplicated P. falciparum infection. METHODS: A 28 day onearm, prospective evaluation of the clinical and parasitological response to AL was conducted at Shecha Health Centre, Arba Minch town, Southern Ethiopia. Patients were treated with six-dose regimen of AL over three days and monitored for 28 days with clinical and laboratory assessments. Participant recruitment and outcome classification was done in accordance with the 2009 WHO methods for surveillance of anti-malarial drug efficacy guidelines. RESULTS: A total of 88 study participants were enrolled and 69 of them completed the study with adequate clinical and parasitological response. Two late parasitological failures were observed, of which one was classified as a recrudescence by polymerase chain reaction (PCR). The PCRcorrected cure rate was 98.6% (95% CI 92.3-100). AL demonstrated a rapid parasite and fever clearance with no parasitaemia on day 2 and febrile cases on day 3. Gametocyte clearance was complete by day three. No serious adverse events were reported during the 28 days follow-up. CONCLUSION: The study demonstrated high therapeutic efficacy and good safety profile of AL. This suggests the continuation of AL as the first-line drug for the treatment of uncomplicated P. falciparum malaria in Ethiopia. Periodic therapeutic efficacy studies and monitoring of markers of resistance are recommended for early detection of resistant parasites.


Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Humanos , Lactente , Combinação Arteméter e Lumefantrina/uso terapêutico , Antimaláricos/efeitos adversos , Etiópia/epidemiologia , Artemisininas/efeitos adversos , Artemeter/uso terapêutico , Plasmodium falciparum , Combinação de Medicamentos , Fluorenos/efeitos adversos , Resultado do Tratamento , Etanolaminas/efeitos adversos , Malária Falciparum/epidemiologia , Febre/tratamento farmacológico
6.
Plant Physiol Biochem ; 195: 37-46, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36599274

RESUMO

Heavy metal (HM) toxicity is a well-known hazard which causes deleterious impact on the growth and development of plants. The impact of abscisic acid (ABA) in presence of silicon (Si) on plant development and quality traits has largely gone unexplored. The effects of ABA and Si on the growth, yield, and quality characteristics of Artemisia annua L. plants growing under copper (Cu) stress (20 and 40 mg kg-1) were investigated in a pot experiment. During this investigation, Cu stress caused severe damage to the plants but exogenous administration of Si and ABA ameliorated the harmful effects of Cu toxicity, and the plants displayed higher biomass and improved physio-biochemical attributes. Copper accumulated in the roots and shoots and its toxicity caused oxidative stress as demonstrated by the increased 2-thiobarbituric acid reactive substance (TBARS) content. It also resulted in the increased activity of antioxidant enzymes, however, the exogenous Si and ABA supplementation decreased the buildup of reactive oxygen species (ROS) and lipid peroxidation, alleviating the oxidative damage produced by HM stress. Copper toxicity had a considerable negative impact on glandular trichome density, ultrastructure as well as artemisinin production. However, combined Si and ABA enhanced the size and density of glandular trichomes, resulting in higher artemisinin production. Taken together, our results demonstrated that exogenous ABA and Si supplementation protect A. annua plants against Cu toxicity by improving photosynthetic characteristics, enhancing antioxidant enzyme activity, protecting leaf structure and integrity, avoiding excess Cu deposition in shoot and root tissues, and helping in enhanced artemisinin biosynthesis. Our results indicate that the combined application of Si and ABA improved the overall growth of plants and may thus be used as an effective approach for the improvement of growth and yield of A. annua in Cu-contaminated soils.


Assuntos
Artemisia annua , Artemisininas , Ácido Abscísico/farmacologia , Cobre/toxicidade , Antioxidantes/farmacologia , Silício/farmacologia
7.
Malar J ; 22(1): 32, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36707795

RESUMO

BACKGROUND: When people with human immunodeficiency virus (HIV) infection (PWH) develop malaria, they are at risk of poor anti-malarial treatment efficacy resulting from impairment in the immune response and/or drug-drug interactions that alter anti-malarial metabolism. The therapeutic efficacy of artemether-lumefantrine was evaluated in a cohort of PWH on antiretroviral therapy (ART) and included measurement of day 7 lumefantrine levels in a subset to evaluate for associations between lumefantrine exposure and treatment response. METHODS: Adults living with HIV (≥ 18 years), on ART for ≥ 6 months with undetectable HIV RNA viral load and CD4 count ≥ 250/mm3 were randomized to daily trimethoprim-sulfamethoxazole (TS), weekly chloroquine (CQ) or no prophylaxis. After diagnosis of uncomplicated Plasmodium falciparum malaria, a therapeutic efficacy monitoring was conducted with PCR-correction according to WHO guidelines. The plasma lumefantrine levels on day 7 in 100 episodes of uncomplicated malaria was measured. A frailty proportional hazards model with random effects models to account for clustering examined the relationship between participant characteristics and malaria treatment failure within 28 days. Pearson's Chi-squared test was used to compare lumefantrine concentrations among patients with treatment failure and adequate clinical and parasitological response (ACPR). RESULTS: 411 malaria episodes were observed among 186 participants over 5 years. The unadjusted ACPR rate was 81% (95% CI 77-86). However, after PCR correction to exclude new infections, ACPR rate was 94% (95% CI 92-97). Increasing age and living in Ndirande were associated with decreased hazard of treatment failure. In this population of adults with HIV on ART, 54% (51/94) had levels below a previously defined optimal day 7 lumefantrine level of 200 ng/ml. This occurred more commonly among participants who were receiving an efavirenz-based ART compared to other ART regimens (OR 5.09 [95% CI 1.52-7.9]). Participants who experienced treatment failure had lower day 7 median lumefantrine levels (91 ng/ml [95% CI 48-231]) than participants who experienced ACPR (190 ng/ml [95% CI 101-378], p-value < 0.008). CONCLUSION: Recurrent malaria infections are frequent in this population of PWH on ART. The PCR-adjusted efficacy of AL meets the WHO criteria for acceptable treatment efficacy. Nevertheless, lumefantrine levels tend to be low in this population, particularly in those on efavirenz-based regimens, with lower concentrations associated with more frequent malaria infections following treatment. These results highlight the importance of understanding drug-drug interactions when diseases commonly co-occur.


Assuntos
Antimaláricos , Artemisininas , Infecções por HIV , Malária Falciparum , Malária , Humanos , Adulto , Antimaláricos/uso terapêutico , Malaui , Artemisininas/uso terapêutico , Artemeter/uso terapêutico , Combinação de Medicamentos , Combinação Arteméter e Lumefantrina/uso terapêutico , Malária/tratamento farmacológico , Malária Falciparum/tratamento farmacológico , Malária Falciparum/prevenção & controle , Lumefantrina/uso terapêutico , Infecções por HIV/tratamento farmacológico , Resultado do Tratamento , Etanolaminas/uso terapêutico , Fluorenos/uso terapêutico
8.
Drug Deliv ; 30(1): 2168794, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36708154

RESUMO

The aim of this study is to demonstrate a method for improving the solubility and relative bioavailability of artemisinin using a self-emulsifying drug delivery system (SEDDS). The self-emulsifying drug load, solubility, and emulsifying time were used as the evaluation indices, based on a solubility test and a ternary phase diagram. Optimal Mixture Design in Design-Expert software was used to optimize the prescription of the artemisinin SEDDS. By determining the water distribution coefficient in vitro, combined with the drug concentration-time curve in vivo, a comparison was made of the relative oral bioavailability of the artemisinin SEDDS and the crude drug. The optimal prescription ratio of oleic acid polyethylene glycol glyceride, polyoxyethylene hydrogenated castor oil, and diethylene glycol monoethyl ether in the artemisinin SEDDS was 0.5:0.2:0.3 (wt/wt/wt), with a drug loading capacity of 41.556 mg/g, a solubility of 1.997 mg/mL, and a self-emulsification time of 214 s. The optimal prescription was transparent, slightly yellow, and oil-like. The average loading capacity of artemisinin was 41.912 mg/g, the emulsification time was 231 s, the average particle size was 128.0 nm, the average Zeta potential was -4.29 mV, and the solubility of artemisinin SEDDS in water was 1.997 mg mL-1. It is 33.85 times of the solubility of artemisinin in water, which achieves the purpose of increasing the solubility of artemisinin. The comparison of the oil/water distribution coefficient of the artemisinin SEDDS with that of the crude drug in vitro showed that SEDDS could improve the permeability of artemisinin and promote the absorption in vivo, and the relative bioavailability of the SEDDS agent was at least 1.47 times higher than that of the crude drug. The artemisinin SEDDS could significantly improve the solubility and relative bioavailability of artemisinin.


Assuntos
Artemisininas , Química Farmacêutica , Emulsões , Disponibilidade Biológica , Química Farmacêutica/métodos , Sistemas de Liberação de Medicamentos/métodos , Solubilidade , Administração Oral
9.
Eur J Pharmacol ; 939: 175467, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36543288

RESUMO

Artemisinin and its derivatives are the main therapeutic drugs against Plasmodium protists, the causative agents of malaria. While several putative mechanisms of action have been proposed, the precise molecular targets of these compounds have not been fully elucidated. In addition to their antimalarial properties, artemisinins have been reported to act as anti-tumour agents and certain antinociceptive effects have also been proposed. We investigated the effect of the parent compound, artemisinin, on a number of temperature-gated Transient Receptor Potential ion channels (so called thermoTRPs), given their demonstrated roles in pain-sensing and cancer. We report that artemisinin acts as an agonist of the Transient Receptor Potential Ankyrin type 1 (TRPA1) receptor channel. Artemisinin was able to evoke calcium transients in HEK293T cells expressing recombinant human TRPA1, as well as in a subpopulation of mouse dorsal root ganglion (DRG) neurons which also responded to the selective TRPA1 agonist allyl isothiocyanate (AITC) and these responses were reversibly abolished by the selective TRPA1 antagonist A967079. Artemisinin also triggered whole-cell currents in HEK293T cells transiently transfected with human TRPA1, as well as in TRPA1-expressing DRG neurons, and these currents were inhibited by A967079. Interestingly, using human TRPA1 mutants, we demonstrate that artemisinin acts as a non-electrophilic agonist of TRPA1, activating the channel in a similar manner to carvacrol and menthol. These results may provide a better understanding of the biological actions of the very important antimalarial and anti-tumour agent artemisinin.


Assuntos
Antimaláricos , Artemisininas , Canais de Potencial de Receptor Transitório , Camundongos , Humanos , Animais , Anquirinas/farmacologia , Antimaláricos/farmacologia , Canal de Cátion TRPA1 , Células HEK293 , Artemisininas/farmacologia , Gânglios Espinais
10.
Lancet Glob Health ; 11(2): e256-e264, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36565705

RESUMO

BACKGROUND: Rectal artesunate, an efficacious pre-referral treatment for severe malaria in children, was deployed at scale in Uganda, Nigeria, and DR Congo. In addition to distributing rectal artesunate, implementation required additional investments in crucial but neglected components in the care for severe malaria. We examined the real-world costs and constraints to rectal artesunate implementation. METHODS: We collected primary data on baseline health system constraints and subsequent rectal artesunate implementation expenditures. We calculated the equivalent annual cost of rectal artesunate implementation per child younger than 5 years at risk of severe malaria, from a health system perspective, separating neglected routine health system components from incremental costs of rectal artesunate introduction. FINDINGS: The largest baseline constraints were irregular health worker supervisions, inadequate referral facility worker training, and inadequate malaria commodity supplies. Health worker training and behaviour change campaigns were the largest startup costs, while supervision and supply chain management accounted for most annual routine costs. The equivalent annual costs of preparing the health system for managing severe malaria with rectal artesunate were US$2·63, $2·20, and $4·19 per child at risk and $322, $219, and $464 per child treated in Uganda, Nigeria, and DR Congo, respectively. Strengthening the neglected, routine health system components accounted for the majority of these costs at 71·5%, 65·4%, and 76·4% of per-child costs, respectively. Incremental rectal artesunate costs accounted for the minority remainder. INTERPRETATION: Although rectal artesunate has been touted as a cost-effective pre-referral treatment for severe malaria in children, its real-world potential is limited by weak and under-financed health system components. Scaling up rectal artesunate or other interventions relying on community health-care providers only makes sense alongside additional, essential health system investments sustained over the long term. FUNDING: Unitaid. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.


Assuntos
Antimaláricos , Artemisininas , Malária , Humanos , Artesunato/uso terapêutico , Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Malária/tratamento farmacológico , África ao Sul do Saara
11.
Eur J Med Chem ; 247: 115000, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36538859

RESUMO

Artemisinin is the crucial ingredient of artemisia annua, a traditional Chinese medicine used for the therapy of malaria in China for hundreds of years. In recent years, the anticancer properties of artemisinin and its derivatives have also been reported. This review has summarized the research and development of artemisinin and its derivatives as anticancer agents, which included both natural and synthetic monomers as well as their dimers. In addition, it highlights the antitumor effects of artemisinin and its derivatives after site-modification or after transformation to a nano-delivery system. Moreover, we have further explored their potential mechanisms of action and also discussed the clinical trials of ARTs used to treat cancer, which will facilitate in further development of novel anticancer drugs based on the scaffold of artemisinin.


Assuntos
Antimaláricos , Antineoplásicos , Artemisininas , Malária , Humanos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Malária/tratamento farmacológico
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 289: 122253, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36542922

RESUMO

Artemisinin (ART) is a type of frontline drug to treat drug-resistant falciparum malaria. Simple, accurate and selective determination of ART is significant to monitor its clinical pharmaceutical efficacy. Herein, a new ratiometric fluorescence method has been designed for the determination of ART with Zn-MOF as fluorescence reference and hemin as catalyst, respectively. Zn-MOF possesses intrinsic fluorescence at 443 nm owing to 2-aminoterephthalic acid ligand. When o-phenylenediamine (OPD) is mixed with hemin, a weak fluorescent signal at 570 nm ascribed to oxidized product of OPD (oxOPD) is observed. In the presence of ART, hemin can catalyze ART to break its peroxide bridge and release a large number of reactive oxygen species, which effectively oxidize OPD into luminescent oxOPD. Therefore, the fluorescence at 570 nm is enhanced significantly while the fluorescence of Zn-MOF remains basically unchanged. Thus, a ratiometric fluorescence sensing platform has been constructed for the detection of ART. This method exhibits wider linear range (0.15 µM-150 µM) with detection limit of 50 nM. This novel and selective method has been used to detect ART in compound naphthoquinone phosphate tablets.


Assuntos
Artemisininas , Hemina , Fluorescência , Corantes , Zinco , Limite de Detecção , Corantes Fluorescentes
13.
Biochem J ; 480(1): 25-39, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36511651

RESUMO

Proteins associated with ubiquitin-proteasome system (UPS) are potential drug targets in the malaria parasite. The ubiquitination and deubiquitination are key regulatory processes for the functioning of UPS. In this study, we have characterized the biochemical and functional role of a novel ubiquitin-specific protease (USP) domain-containing protein of the human malaria parasite Plasmodium falciparum (PfUSP). We have shown that the PfUSP is an active deubiquitinase associated with parasite endoplasmic reticulum (ER). Selection linked integration (SLI) method for C-terminal tagging and GlmS-ribozyme mediated inducible knock-down (iKD) of PfUSP was utilized to assess its functional role. Inducible knockdown of PfUSP resulted in a remarkable reduction in parasite growth and multiplication; specifically, PfUSP-iKD disrupted ER morphology and development, blocked the development of healthy schizonts, and hindered proper merozoite development. PfUSP-iKD caused increased ubiquitylation of specific proteins, disrupted organelle homeostasis and reduced parasite survival. Since the mode of action of artemisinin and the artemisinin-resistance are shown to be associated with the proteasome machinery, we analyzed the effect of dihydroartemisinin (DHA) on PfUSP-iKD parasites. Importantly, the PfUSP-knocked-down parasite showed increased sensitivity to dihydroartemisinin (DHA), whereas no change in chloroquine sensitivity was observed, suggesting a role of PfUSP in combating artemisinin-induced cellular stress. Together, the results show that Plasmodium PfUSP is an essential protease for parasite survival, and its inhibition increases the efficacy of artemisinin-based drugs. Therefore, PfUSP can be targeted to develop novel scaffolds for developing new antimalarials to combat artemisinin resistance.


Assuntos
Antimaláricos , Artemisininas , Malária , Parasitos , Humanos , Animais , Plasmodium falciparum/metabolismo , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Proteases Específicas de Ubiquitina/farmacologia , Artemisininas/farmacologia , Artemisininas/metabolismo , Antimaláricos/química , Ubiquitina/genética , Ubiquitina/metabolismo , Resistência a Medicamentos/genética
14.
Zhongguo Zhong Yao Za Zhi ; 47(21): 5717-5734, 2022 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-36471990

RESUMO

This study aimed to forecast the main active components of Xiaoer Chiqiao Qingre Granules(XECQ) in the treatment of children with acute upper respiratory tract infection by UPLC-MS, network pharmacology, molecular docking and cell biology, and explore the mechanism of action, so as to provide certain reference for the research on its pharmacodynamics substances and mechanism of action. The main chemical components of XECQ were comprehensively analyzed by UPLC-Q-TOF-MS combined with UNIFI platform. According to the MS1 and MS2 data of XECQ, comparison and identification were carried out in combination with reference substances and reference articles. On this basis, the chemical components of XECQ were targeted and enriched by network pharmacology, to screen the main pharmacodynamic substances of XECQ in the treatment of acute upper respiratory tract infection in children and discuss the mechanism of action. In addition, the binding degree of core targets and main active components was verified by molecular docking. The results revealed that 202 compounds were identified from XECQ, among which 22 were the main active components, including obovatol, dihydroartemisinin, and longikaurin A. Enrichment analysis of the key target pathways showed that XECQ played its role in the treatment of children with acute upper respiratory tract infection mainly by regulating PI3K/Akt signaling pathway and MAPK signaling pathway. In the experimental verification by Western Blot(WB), it was found that XECQ significantly inhibited the expression of PI3K and Akt, which was consistent with the prediction results of network pharmacology. In conclusion, the potential pharmacodynamic substances of XECQ were obovatol, dihydroartemisinin, longikaurin A and other 19 active components. It treated children with acute upper respiratory tract infection by regulating the PI3K/Akt signaling pathway.


Assuntos
Artemisininas , Medicamentos de Ervas Chinesas , Infecções Respiratórias , Criança , Humanos , Cromatografia Líquida , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt , Espectrometria de Massas em Tandem , Infecções Respiratórias/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia
15.
Malar J ; 21(1): 369, 2022 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-36464686

RESUMO

BACKGROUND: Artemisinin-based combination therapy (ACT) has been recommended as the first-line treatment by the World Health Organization to treat uncomplicated Plasmodium falciparum malaria. However, the emergence and spread of P. falciparum resistant to artemisinins and their partner drugs is a significant risk for the global effort to reduce disease burden facing the world. Currently, dihydroartemisinin-piperaquine (DHA-PPQ) is the most common drug used to treat P. falciparum, but little evidence about the resistance status targeting DHA (ACT drug) and its partner drug (PPQ) has been reported in Shandong Province, China. METHODS: A retrospective study was conducted to explore the prevalence and spatial distribution of Pfk13 and Pfcrt polymorphisms (sites of 72-76, and 93-356) among imported P. falciparum isolates between years 2015-2019 in Shandong Province in eastern China. Individual epidemiological information was collected from a web-based reporting system were reviewed and analysed. RESULTS: A total of 425 P. falciparum blood samples in 2015-2019 were included and 7.3% (31/425) carried Pfk13 mutations. Out of the isolates that carried Pfk13 mutations, 54.8% (17/31) were nonsynonymous polymorphisms. The mutant alleles A578S, Q613H, C469C, and S549S in Pfk13 were the more frequently detected allele, the mutation rate was the same as 9.7% (3/31). Another allele Pfk13 C580Y, closely associated with artemisinin (ART) resistance, was found as 3.2% (2/31), which was found in Cambodia. A total of 14 mutant isolates were identified in Western Africa countries (45.2%, 14/31). For the Pfcrt gene, the mutation rate was 18.1% (77/425). T76T356 and T76 were more frequent in all 13 different haplotypes with 26.0% (20/77) and 23.4% (18/77). The CVIET and CVIKT mutant at loci 72-76 have exhibited a prevalence of 19.5% (15/77) and 3.9% (3/77), respectively. The CVIET was mainly observed in samples from Congo (26.7%, 4/15) and Mozambique (26.7%, 4/15). No mutations were found at loci 97, 101 and 145. For polymorphisms at locus 356, a total of 24 isolates were identified and mainly from Congo (29.2%, 7/24). CONCLUSION: These findings indicate a low prevalence of Pfk13 in the African isolates. However, the emergence and increase in the new alleles Pfcrt I356T, reveals a potential risk of drug pressure in PPQ among migrant workers returned from Africa. Therefore, continuous molecular surveillance of Pfcrt mutations and in vitro susceptibility tests related to PPQ are necessary.


Assuntos
Artemisininas , Malária Falciparum , Humanos , Plasmodium falciparum/genética , Estudos Retrospectivos , Artemisininas/farmacologia , Malária Falciparum/epidemiologia , China/epidemiologia
16.
Malar J ; 21(1): 359, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36451216

RESUMO

BACKGROUND: Routine monitoring of anti-malarial drugs is recommended for early detection of drug resistance and to inform national malaria treatment guidelines. In Ethiopia, the national treatment guidelines employ a species-specific approach. Artemether-lumefantrine (AL) and chloroquine (CQ) are the first-line schizonticidal treatments for Plasmodium falciparum and Plasmodium vivax, respectively. The National Malaria Control and Elimination Programme in Ethiopia is considering dihydroartemisinin-piperaquine (DHA/PPQ) as an alternative regimen for P. falciparum and P. vivax. METHODS: The study assessed the clinical and parasitological efficacy of AL, CQ, and DHA/PPQ in four arms. Patients over 6 months and less than 18 years of age with uncomplicated malaria mono-infection were recruited and allocated to AL against P. falciparum and CQ against P. vivax. Patients 18 years or older with uncomplicated malaria mono-infection were recruited and randomized to AL or dihydroartemisinin-piperaquine (DHA/PPQ) against P. falciparum and CQ or DHA/PPQ for P. vivax. Patients were followed up for 28 (for CQ and AL) or 42 days (for DHA/PPQ) according to the WHO recommendations. Polymerase chain reaction (PCR)-corrected and uncorrected estimates were analysed by Kaplan Meier survival analysis and per protocol methods. RESULTS: A total of 379 patients were enroled in four arms (n = 106, AL-P. falciparum; n = 75, DHA/PPQ- P. falciparum; n = 142, CQ-P. vivax; n = 56, DHA/PPQ-P. vivax). High PCR-corrected adequate clinical and parasitological response (ACPR) rates were observed at the primary end points of 28 days for AL and CQ and 42 days for DHA/PPQ. ACPR rates were 100% in AL-Pf (95% CI: 96-100), 98% in CQ-P. vivax (95% CI: 95-100) at 28 days, and 100% in the DHA/PPQ arms for both P. falciparum and P. vivax at 42 days. For secondary endpoints, by day three 99% of AL-P. falciparum patients (n = 101) cleared parasites and 100% were afebrile. For all other arms, 100% of patients cleared parasites and were afebrile by day three. No serious adverse events were reported. CONCLUSION: This study demonstrated high therapeutic efficacy for the anti-malarial drugs currently used by the malaria control programme in Ethiopia and provides information on the efficacy of DHA/PPQ for the treatment of P. falciparum and P. vivax as an alternative option.


Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Malária Vivax , Humanos , Combinação Arteméter e Lumefantrina/uso terapêutico , Cloroquina/uso terapêutico , Plasmodium falciparum , Antimaláricos/uso terapêutico , Plasmodium vivax , Etiópia , Artemeter , Artemisininas/uso terapêutico , Malária Vivax/tratamento farmacológico , Malária Falciparum/tratamento farmacológico
17.
Oxid Med Cell Longev ; 2022: 6568748, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36567858

RESUMO

Oxidative stress plays a key role in cerebral ischemia/reperfusion injury. Artemisinin (ART) has antioxidative stress activity in addition to its powerful antimalarial effects. In this article, we investigated the effect of ART on OGD/R-induced oxidative stress injury and its underlying mechanisms. We used oxygen-glucose deprivation/reoxygenation (OGD/R) to establish an in vitro model of cerebral ischemia/reperfusion (I/R) injury. CCK-8 and lactate dehydrogenase (LDH) release were used to assess cellular damage. Measurement of reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), and mitochondrial membrane potential (MMP) estimates oxidative stress-induced damage and protection from ART effect. OGD/R treatment aggravated oxidative stress damage, whereas ART reversed the effects of OGD/R. Autophagy is closely related to oxidative stress; in order to confirm whether the antioxidative stress effect of ART is related to PHB2-mediated autophagy, we examined the protein expression of prohibitin 2 (PHB2), TOMM20, p62, and the conversion of microtubule-associated protein light chain 3I (LC3I) to LC3II and found that the protein expression of PHB2, TOMM20, p62, and LC3II/LC3I was significantly correlated with OGD/R treatment. The colocalization of PHB2 and LC3, TOMM20, and LC3 was reduced after OGD/R treatment, and ART reversed this change. After silencing PHB2, the protective effect of ART against OGD/R-induced oxidative stress injury was reduced, the protein expressions of PHB2, TOMM20 and LC3II/LC3I and the colocalization of PHB2 and LC3, TOMM20, and LC3 were decreased. We used chloroquine to block the lysosomal pathway and found that ART increased the conversion of LC3I to LC3II, silencing PHB2 which inhibited the conversion of LC3I to LC3II, and impaired mitophagy. Our findings showed that ART attenuated OGD/R-induced oxidative stress damage through PHB2-mediated mitophagy. To the current knowledge, our study is the first to demonstrate that ART attenuates OGD/R-induced oxidative stress injury through PHB2-mediated autophagy in the human neuroblastoma SH-SY5Y cell line, which provided new insights into the treatment of OGD/R injury.


Assuntos
Artemisininas , Isquemia Encefálica , Neuroblastoma , Traumatismo por Reperfusão , Humanos , Apoptose , Neuroblastoma/tratamento farmacológico , Neuroblastoma/metabolismo , Linhagem Celular , Autofagia , Estresse Oxidativo , Isquemia Encefálica/metabolismo , Oxigênio/metabolismo , Traumatismo por Reperfusão/metabolismo , Infarto Cerebral , Reperfusão , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Glucose/metabolismo
18.
Malar J ; 21(1): 386, 2022 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-36528584

RESUMO

BACKGROUND: Malaria remains one of the most virulent and deadliest parasitic disease in the world, particularly in Africa and Southeast Asia. Widespread occurrence of artemisinin-resistant Plasmodium falciparum strains from the Greater Mekong Subregion is alarming. This hinders the national economies, as well as being a major drawback in the effective control and elimination of malaria worldwide. Clearly, an effective anti-malarial drug is urgently needed. METHODS: The dinuclear and mononuclear copper(II) and zinc(II) complexes were synthesized in ethanolic solution and characterized by various physical measurements (FTIR, CHN elemental analysis, solubility, ESI-MS, UV-Visible, conductivity and magnetic moment, and NMR). X-ray crystal structure of the dicopper(II) complex was determined. The in vitro haemolytic activities of these metal complexes were evaluated spectroscopically on B+ blood while the anti-malarial potency was performed in vitro on blood stage drug-sensitive Plasmodium falciparum 3D7 (Pf3D7) and artemisinin-resistant Plasmodium falciparum IPC5202 (Pf5202) with fluorescence dye. Mode of action of metal complexes were conducted to determine the formation of reactive oxygen species using PNDA and DCFH-DA dyes, JC-1 depolarization of mitochondrial membrane potential, malarial 20S proteasome inhibition with parasite lysate, and morphological studies using Giemsa and Hoechst stains. RESULTS: Copper(II) complexes showed anti-malarial potency against both Pf3D7 and Pf5202 in sub-micromolar to micromolar range. The zinc(II) complexes were effective against Pf3D7 with excellent therapeutic index but encountered total resistance against Pf5202. Among the four, the dinuclear copper(II) complex was the most potent against both strains. The zinc(II) complexes caused no haemolysis of RBC while copper(II) complexes induced increased haemolysis with increasing concentration. Further mechanistic studies of both copper(II) complexes on both Pf3D7 and Pf5202 strains showed induction of ROS, 20S malarial proteasome inhibition, loss of mitochondrial membrane potential and morphological features indicative of apoptosis. CONCLUSION: The dinuclear [Cu(phen)-4,4'-bipy-Cu(phen)](NO3)4 is highly potent and can overcome the total drug-resistance of Pf5202 towards chloroquine and artemisinin. The other three copper(II) and zinc(II) complexes were only effective towards the drug-sensitive Pf3D7, with the latter causing no haemolysis of RBC. Their mode of action involves multiple targets.


Assuntos
Antimaláricos , Artemisininas , Complexos de Coordenação , Malária Falciparum , Malária , Humanos , Plasmodium falciparum , Antimaláricos/uso terapêutico , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/uso terapêutico , Cobre/farmacologia , Cobre/uso terapêutico , Artemisininas/uso terapêutico , Resistência a Medicamentos , Malária/tratamento farmacológico , Metais , Zinco/farmacologia , Zinco/uso terapêutico , Malária Falciparum/tratamento farmacológico
19.
Microb Cell Fact ; 21(1): 279, 2022 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-36587216

RESUMO

Amorphadiene is the precursor to synthesize the antimalarial drug artemisinin. The production of amorphadiene and artemisinin from metabolically engineered microbes may provide an alternate to plant secondary metabolite extraction. Microbial consortia can offer division of labor, and microbial co-culture system can be leveraged to achieve cost-efficient production of natural products. Using a co-culture system of Y. lipolytica Po1f and Po1g strains, subcellular localization of ADS gene (encoding amorphadiene synthase) into the endoplasmic reticulum, co-utilization of mixed carbon source, and enlargement of the endoplasmic reticulum (ER) surface area, we were able to significantly improve amorphadiene production in this work. Using Po1g/PPtM and Po1f/AaADSERx3/iGFMPDU strains and co-utilization of 5 µM sodium acetate with 20 g/L glucose in YPD media, amorphadiene titer were increased to 65.094 mg/L. The enlargement of the ER surface area caused by the deletion of the PAH1 gene provided more subcellular ER space for the action of the ADS-tagged gene. It further increased the amorphadiene production to 71.74 mg/L. The results demonstrated that the importance of the spatial localization of critical enzymes, and manipulating metabolic flux in the co-culture of Y. lipolytica can be efficient over a single culture for the bioproduction of isoprenoid-related secondary metabolites in a modular manner.


Assuntos
Artemisininas , Yarrowia , Yarrowia/genética , Yarrowia/metabolismo , Técnicas de Cocultura , Engenharia Metabólica/métodos , Artemisininas/metabolismo
20.
Int J Mol Sci ; 23(24)2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36555409

RESUMO

A series of novel 1,3,4-oxadiazole-artemisinin hybrids have been designed and synthesized. An MTT assay revealed that most of tested hybrids showed more enhanced anti-proliferative activities than artemisinin, among which A8 had the superior potency with IC50 values ranging from 4.07 µM to 9.71 µM against five tested cancer cell lines. Cell colony formation assays showed that A8 could inhibit significantly more cell proliferation than artemisinin and 5-fluorouracil. Further mechanism studies reveal that A8 induces apoptosis and ferroptosis in MCF-7 cells in a dose-dependent manner, and CYPs inhibition assays reveal that A8 has a moderate inhibitory effect on CYP1A2 and CYP3A4 in the human body at 10 µM. The present work indicates that hybrid A8 may merit further investigation as a potential therapeutic agent.


Assuntos
Antineoplásicos , Artemisininas , Ferroptose , Humanos , Células MCF-7 , Estrutura Molecular , Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Apoptose , Artemisininas/farmacologia , Proliferação de Células , Relação Estrutura-Atividade , Linhagem Celular Tumoral
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