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1.
Malar J ; 23(1): 278, 2024 Sep 13.
Article in English | MEDLINE | ID: mdl-39272079

ABSTRACT

BACKGROUND: Over the past years, there has been a growing concern that a considerable amount of anti-malarial supply in the underdeveloped world particularly in the private sector, is of poor quality. The World Health Organization (WHO) has received about 1500 reports that mentions instances of substandard and falsified products since 2013. The majority of the reports concerned antibiotics and anti-malarials. The majority of reports (42%) originate from the WHO African region. OBJECTIVE: This study intends to assess the quality of the most widely used anti-malarial medications [artemether-lumefantrine tablets, chloroquine phosphate tablets, primaquine phosphate tablets, artesunate, and artemether injections] in Gambella, South-West, Ethiopia. METHODS: A total of 52 samples were collected on June 2022 from Gambella National Regional State, Ethiopia. Half of the districts (six) located in the four zones of the region were chosen using simple random sampling technique. All drug retail outlets available in the selected districts (locally known as woredas) were included. The samples were subjected to visual inspection with a tool adopted from the joint WHO/FIP/ USP checklist. The pharmacopeial tests for identification, uniformity of dosage forms, assay, thickness, diameter, hardness, friability, disintegration test, dissolution, and sterility tests were carried out according to the USP 44-NF 39 and International Pharmacopoeia 11th edition, 2022 monographs. RESULTS AND DISCUSSION: Only 25% of the samples were registered on the Ethiopian Food and Drug Authority (EFDA's) electronic regulatory/ registration system (ERIS). Besides, 88.8% of artemether injection products were presented in clear glass ampoules. This might expose the products to photochemical degradation that leads to in loss of anti-plasmodial activity. In addition, 50% of the artemether products assessed were not bioequivalent with the comparator product in the in vitro dissolution comparison tests. Overall, the study findings reveal a high prevalence (58.3%) of substandard anti-malarial drugs in the region. The stated percent of the samples had failed in one or more of the quality test parameters assessed in this study. CONCLUSION: The study findings reveal a high prevalence (58.3%) of substandard anti-malarial drugs in the region. Only a quarter were registered and 38% of the unregistered products failed the quality tests. Hence, the national, regional medicine regulatory bodies and other stake holders should perform the required roles to circumvent presence of Substandard and Falsified (SF) anti-malarial drugs in the study sites.


Subject(s)
Antimalarials , Antimalarials/analysis , Antimalarials/standards , Antimalarials/chemistry , Ethiopia , Artemether, Lumefantrine Drug Combination/analysis , Quality Control , Substandard Drugs/analysis , Counterfeit Drugs/analysis , Artesunate/analysis , Chloroquine/analysis , Primaquine/analysis , Humans
2.
Nat Commun ; 15(1): 7923, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39256387

ABSTRACT

Ferroptosis is a promising strategy for cancer therapy, with numerous inhibitors of its braking axes under investigation as potential drugs. However, few studies have explored the potential of activating the driving axes to induce ferroptosis. Herein, phosphatidylcholine peroxide decorating liposomes (LIPPCPO) are synthesized to induce ferroptosis by targeting divalent metal transporter 1 (DMT1). LIPPCPO is found to boost lysosomal Fe2+ efflux by inducing cysteinylation of lysosomal DMT1, resulting in glutathione peroxidase 4 (GPX4) suppression, glutathione depletion and ferroptosis in breast cancer cells and xenografts. Importantly, LIPPCPO induced ferroptotic cell death is independent of acquired resistance to radiation, chemotherapy, or targeted agents in 11 cancer cell lines. Furthermore, a strong synergistic ferroptosis effect is observed between LIPPCPO and an FDA-approved drug, artesunate, as well as X rays. The formula of LIPPCPO encapsulating artesunate significantly inhibits tumor growth and metastasis and improves the survival rate of breast cancer-bearing female mice. These findings provide a distinct strategy for inducing ferroptosis and highlight the potential of LIPPCPO as a vector to synergize the therapeutic effects of conventional ferroptosis inducers.


Subject(s)
Breast Neoplasms , Ferroptosis , Liposomes , Phospholipid Hydroperoxide Glutathione Peroxidase , Ferroptosis/drug effects , Animals , Humans , Female , Cell Line, Tumor , Mice , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Breast Neoplasms/genetics , Breast Neoplasms/drug therapy , Liposomes/metabolism , Phospholipid Hydroperoxide Glutathione Peroxidase/metabolism , Phospholipid Hydroperoxide Glutathione Peroxidase/genetics , Artesunate/pharmacology , Xenograft Model Antitumor Assays , Phosphatidylcholines/metabolism , Phosphatidylcholines/chemistry , Iron/metabolism , Lysosomes/metabolism , Lysosomes/drug effects , Mice, Nude , Glutathione/metabolism , Mice, Inbred BALB C
3.
Bioorg Chem ; 152: 107733, 2024 Nov.
Article in English | MEDLINE | ID: mdl-39180865

ABSTRACT

A series of organoselenium compounds based on the hybridization of artesunate (ART) scaffolds and Se functionalities (-SeCN and -SeCF3) were synthesized. The redox properties of artesunate-SeCN and artesunate-SeCF3 derivatives were conducted by 2, 2-didiphenyl-1-picrylhydrazyl (DPPH), and the results showed that compounds 2c, 2f and 3e have a good free radical scavenging activity. Their cytotoxicity was evaluated against four types of cancer cell lines, SW480 (human colon adenocarcinoma cells), HCT116 (human colorectal adenocarcinoma cells), HepG2 (human hepatocellular carcinoma cells), MCF-7 (human breast cancer cells). The MTT results showed that compared with ART and 5-FU, compound 2c exhibited potent in vitro antiproliferative activity in SW480, HCT116, and MCF-7 cancer cell lines, and was thus chose for further antitumor mechanism investigation. The antitumor mechanism study revealed that compound 2c induced ferroptosis in HCT116 cells by inhibiting the expression of GPX4 protein, accompanying by the up-regulation of intracellular ROS levels. Mitochondria in HCT116 cells exhibit depolarization of mitochondrial membrane potential (MMP) and ultrastructural changes in morphology, which indicated that 2c resulted in mitochondrial dysfunction and ferroptosis. Moreover, 2c could increase the levels of lipid peroxidation and ferrous ion, which further confirm that compound 2c may exert its antitumor effect through ferroptosis. Overall, these results suggest that the artesunate-Se candidates could provide promising new lead derivatives for further potential anticancer drug development.


Subject(s)
Antineoplastic Agents , Artesunate , Cell Proliferation , Drug Design , Drug Screening Assays, Antitumor , Ferroptosis , Phospholipid Hydroperoxide Glutathione Peroxidase , Humans , Artesunate/pharmacology , Artesunate/chemical synthesis , Artesunate/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Ferroptosis/drug effects , Phospholipid Hydroperoxide Glutathione Peroxidase/metabolism , Phospholipid Hydroperoxide Glutathione Peroxidase/antagonists & inhibitors , Cell Proliferation/drug effects , Structure-Activity Relationship , Molecular Structure , Dose-Response Relationship, Drug , Cell Line, Tumor , Reactive Oxygen Species/metabolism , Organoselenium Compounds/pharmacology , Organoselenium Compounds/chemistry , Organoselenium Compounds/chemical synthesis
4.
Dtsch Med Wochenschr ; 149(18): 1090-1093, 2024 Sep.
Article in German | MEDLINE | ID: mdl-39208861

ABSTRACT

MEDICAL HISTORY: A 25-year-old female outpatient presenting with fever and micro-hematuria was treated for urinary tract infection. Her condition worsened over 3 days at home. After experiencing multiple falls caused by leg weakness and mental confusion, she was admitted to a hospital with high fever. DIAGNOSTICS: Initial laboratory findings showed hemolytic anemia, pancytopenia, and acute kidney injury, suggesting hemolytic uremic syndrome. However, a detailed fever evaluation revealed her recent return from Afrika. This prompted a malaria test, which confirmed Plasmodium falciparum infection with 80 % parasitemia. THERAPY AND PROGRESS: Despite the quick reduction of parasitemia following treatment with intravenous administered artesunate and oral Artemether-Lumefantrine, her condition worsened, leading to a septic shock. This required renal replacement and kinetic ventilation therapy, as well as blood transfusions due to persistent hemolysis until the laboratory values normalized after 48 days post-admission. CONCLUSION: The evaluation of fever is often challenging, but most often a detailed patient history is key to early diagnosis and treatment preventing deathly outcomes in severe cases.


Subject(s)
Antimalarials , Malaria, Falciparum , Humans , Female , Adult , Malaria, Falciparum/diagnosis , Malaria, Falciparum/drug therapy , Malaria, Falciparum/complications , Antimalarials/therapeutic use , Plasmodium falciparum , Tanzania , Travel , Artesunate/therapeutic use , Artemether, Lumefantrine Drug Combination/therapeutic use , Shock, Septic/etiology , Shock, Septic/diagnosis
5.
Toxicol Appl Pharmacol ; 491: 117075, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39173720

ABSTRACT

Artesunate (ART) is a derivative of artemisinin and has anti-inflammatory, anti-tumor, and anti-angiogenic properties. Although ART has been implicated in osteoarthritis (OA), the mechanism needs to be further dissected. Here, we explored the effects of ART on the development of OA and the underlying mechanism using destabilization of the medial meniscus (DMM) surgical instability model. Mice with OA were developed using DMM and treated with ART. The pathological morphology of knee joint tissues was examined, and the degeneration of joint cartilage was assessed. Mouse knee chondrocytes were isolated and induced with IL-1ß, followed by ART treatment. ART alleviates OA in mice by elevating ubiquitin carboxyl-terminal hydrolase 7 (USP7) expression, and USP7 inhibitor (P22077) treatment mitigated the protective effects of ART on chondrocytes. We also showed that USP7 mediated the deubiquitination of forkhead box protein O1 (FoxO1), while FoxO1 alleviated chondrocyte injury. In addition, FoxO1 promoted metastasis-associated protein MTA1 (MTA1) transcription, and downregulation of MTA1 exacerbated chondrocyte injury. Our study identifies that USP7/FoxO1/MTA1 is a key signaling cascade in the treatment of ART on OA.


Subject(s)
Artesunate , Chondrocytes , Forkhead Box Protein O1 , Mice, Inbred C57BL , Osteoarthritis , Ubiquitin-Specific Peptidase 7 , Animals , Artesunate/pharmacology , Artesunate/therapeutic use , Forkhead Box Protein O1/metabolism , Forkhead Box Protein O1/genetics , Ubiquitin-Specific Peptidase 7/metabolism , Ubiquitin-Specific Peptidase 7/genetics , Mice , Male , Osteoarthritis/drug therapy , Osteoarthritis/metabolism , Osteoarthritis/pathology , Chondrocytes/drug effects , Chondrocytes/metabolism , Chondrocytes/pathology , Trans-Activators/metabolism , Trans-Activators/genetics , Signal Transduction/drug effects , Repressor Proteins/genetics , Repressor Proteins/metabolism , Transcription, Genetic/drug effects
6.
Acta Histochem ; 126(5-7): 152174, 2024 Oct.
Article in English | MEDLINE | ID: mdl-38976933

ABSTRACT

Choroidal melanoma (CM), a highly metastatic eye tumor, exhibits vasculogenic mimicry (VM) facilitated by hypoxia-induced angiogenesis. This study explored the inhibitory impact of the anti-malarial drug Artesunate (ART) on CM VM through modulation of the HIF-1α/VEGF/PDGF pathway. Immunohistochemistry (IHC) confirmed VM in CM with elevated VEGF and PDGF expression. Hypoxia promoted CM proliferation, upregulating HIF-1α, VEGF and PDGF. VEGF and PDGF enhanced CM migration, invasion and VM, with HIF-1α playing a crucial role. ART mitigated VM formation by suppressing the HIF-1α/VEGF/PDGF pathway, highlighting its potential as an anti-tumor agent in CM.


Subject(s)
Artesunate , Choroid Neoplasms , Hypoxia-Inducible Factor 1, alpha Subunit , Melanoma , Neovascularization, Pathologic , Platelet-Derived Growth Factor , Vascular Endothelial Growth Factor A , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Melanoma/metabolism , Melanoma/drug therapy , Melanoma/pathology , Humans , Choroid Neoplasms/drug therapy , Choroid Neoplasms/metabolism , Choroid Neoplasms/pathology , Platelet-Derived Growth Factor/metabolism , Vascular Endothelial Growth Factor A/metabolism , Artesunate/pharmacology , Neovascularization, Pathologic/metabolism , Neovascularization, Pathologic/drug therapy , Neovascularization, Pathologic/pathology , Signal Transduction/drug effects , Cell Line, Tumor , Male , Cell Proliferation/drug effects
7.
Front Biosci (Landmark Ed) ; 29(7): 266, 2024 Jul 24.
Article in English | MEDLINE | ID: mdl-39082354

ABSTRACT

BACKGROUND: Artesunate (ART) has the potential to modulate the nuclear factor kappa B (NF-κB) and Notch1/Hes1 signaling pathways, which play crucial roles in the pathogenesis of osteoporosis. This study aims to explore whether ART participates in the progression of osteoporosis by regulating these signaling pathways. METHODS: In the in vitro experiments, we treated bone marrow mesenchymal stem cells (BMSCs) with different concentrations of ART (0, 3, 6, 12 µM) and evaluated osteogenic differentiation using alkaline phosphatase staining (ALP) and alizarin red S staining (ARS) staining. The expression levels of osteocalcin (OCN), RUNT-related transcription factor 2 (RUNX2), osteoprotegerin (OPG), and receptor activator of the nuclear factor kappa ligand (RANKL) were detected by real-time quantitative PCR (RT-qPCR). The effects of ART on NF-κB p65 and Notch1 protein expression were analyzed by Western blot (WB) and immunofluorescence (IF). In the in vivo experiments, a postmenopausal osteoporosis rat model was established via ovariectomy. Bone tissue pathological injury was evaluated using hematoxylin eosin (HE) staining. Serum ALP levels were measured using a kit, bone density was determined by dual-energy X-ray absorptiometry, and serum levels of bone gla protein (BGP), OPG, RANKL, tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), and IL-1ß were measured by enzyme-linked immunosorbent assay (ELISA). Additionally, the expression of NF-κB p65 and Notch1 in tissues was assessed by immunohistochemistry. RESULTS: In vitro experiments revealed that compared to the control group, ART dose-dependently promoted BMSCs proliferation and enhanced their osteogenic differentiation capability. The expression of OCN, RUNX2, and OPG significantly increased in the ART-treated group, while RANKL expression decreased significantly (p < 0.05). ART significantly inhibited the expression of NF-κB p65 and Notch1/Hes1 signaling pathway proteins (p < 0.05). Compared to ART treatment alone, combined treatment with ART and phorbol myristate acetate (PMA) or valproic acid (VPA) resulted in increased expression of NF-κB p65 and Notch1 proteins and decreased osteogenic differentiation capability (p < 0.05). In vivo experiments showed that in rats treated with ART, bone damage was significantly reduced, bone density and mineral content were restored considerably, and the expression of inflammatory factors (TNF-α, IL-6, IL-1ß) decreased significantly (p < 0.05). Additionally, ART treatment significantly reduced the expression of NF-κB p65 and Notch1 proteins, increased OPG expression, and decreased BGP and RANKL levels (p < 0.05). CONCLUSION: In summary, ART facilitates the osteogenic differentiation of BMSCs by inhibiting the NF-κB and Notch1/Hes1 signaling pathways, thereby exerting significant protective effects against osteoporosis.


Subject(s)
Artesunate , NF-kappa B , Osteoporosis , Ovariectomy , Rats, Sprague-Dawley , Receptor, Notch1 , Signal Transduction , Animals , Artesunate/pharmacology , Artesunate/therapeutic use , Female , Signal Transduction/drug effects , Receptor, Notch1/metabolism , NF-kappa B/metabolism , Osteoporosis/metabolism , Osteoporosis/drug therapy , Osteoporosis/etiology , Rats , Osteogenesis/drug effects , Artemisinins/pharmacology , Artemisinins/therapeutic use , Mesenchymal Stem Cells/metabolism , Mesenchymal Stem Cells/drug effects , Inflammation/metabolism , Cell Differentiation/drug effects , Transcription Factor HES-1
8.
Cell Commun Signal ; 22(1): 378, 2024 Jul 26.
Article in English | MEDLINE | ID: mdl-39061097

ABSTRACT

Artesunate (ART), a natural product isolated from traditional Chinese plant Artemisia annua, has not been extensively explored for its anti-melanoma properties. In our study, we found that ART inhibited melanoma cell proliferation and induced melanoma cell ferroptosis. Mechanistic study revealed that ART directly targets Ido1, thereby suppressing Hic1-mediated transcription suppression of Hmox1, resulting in melanoma cell ferroptosis. In CD8+ T cells, ART does not cause cell ferroptosis due to the low expression of Hmox1. It also targets Ido1, elevating tryptophan levels, which inhibits NFATc1-mediated PD1 transcription, consequently activating CD8+ T cells. Our study uncovered a potent and synergistic anti-melanoma efficacy arising from ART-induced melanoma cell ferroptosis and concurrently enhancing CD8+ T cell-mediated immune response both in vivo and in vitro through directly targeting Ido1. Our study provides a novel mechanistic basis for the utilization of ART as an Ido1 inhibitor and application in clinical melanoma treatment.


Subject(s)
Artesunate , Ferroptosis , Indoleamine-Pyrrole 2,3,-Dioxygenase , Melanoma , Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism , Indoleamine-Pyrrole 2,3,-Dioxygenase/genetics , Ferroptosis/drug effects , Animals , Artesunate/pharmacology , Artesunate/therapeutic use , Melanoma/drug therapy , Melanoma/pathology , Mice , Cell Line, Tumor , Humans , Mice, Inbred C57BL , CD8-Positive T-Lymphocytes/drug effects , CD8-Positive T-Lymphocytes/immunology , Cell Proliferation/drug effects , Heme Oxygenase-1/metabolism , Heme Oxygenase-1/genetics
9.
Inorg Chem ; 63(31): 14699-14711, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39047187

ABSTRACT

The selective separation and purification of artesunate (ARU) and artemisinin (ART) using zirconium-based metal-organic frameworks (MOF), especially UiO-66 MOF, are receiving increasing attention. In this study, tunable "hydrophobic" sites of thiol (-SH) were introduced to amino-functionalized MOFs (UiO-66-NH2) to fabricate a thiol-amino bifunctional UiO-66/polyvinylidene fluoride (PVDF)-blended membrane (S1-UiO/PVDF-DPIM) via the delayed-phase-inversion method for selective separation of ARU/ART. The adsorption results indicated that the modification of UiO-66-NH2 with thiol can indeed increase the ARU adsorption. The thiol-functional MOF (S1-UiO-66-NH2) was chosen as the optimal thiol-amino bifunctional MOF, as it possessed the maximum ARU adsorption capacity (111.14 mg g-1) and the highest selective-separation factor (α = 51.84). The ATR FT-IR dynamic spectrum disclosed the recognition mechanism, indicating that incorporating thiol groups into a hydrophilic MOF as hydrophobic sites can boost adsorption efficiency. Moreover, the static-selective permeation results showed that the S1-UiO/PVDF-DPIM preferentially transfers ARU when mixed with ART, even achieving complete ARU/ART separation. The most crucial aspect was the introduction of a hydrophobic core of -SH and new spontaneously formed disulfide bonds to S1-UiO/PVDF-DPIM, creating alternated hydrogen bonds and hydrophobic interactions. This work provides an alternative strategy to prepare hydrophobic-hydrophilic MOF-based membranes for the highly efficient and selective separation of complex analogue systems.


Subject(s)
Artesunate , Hydrophobic and Hydrophilic Interactions , Metal-Organic Frameworks , Sulfhydryl Compounds , Metal-Organic Frameworks/chemistry , Metal-Organic Frameworks/chemical synthesis , Sulfhydryl Compounds/chemistry , Sulfhydryl Compounds/isolation & purification , Artesunate/chemistry , Artesunate/pharmacology , Artesunate/isolation & purification , Adsorption , Polyvinyls/chemistry , Membranes, Artificial , Molecular Structure , Artemisinins/chemistry , Artemisinins/isolation & purification , Zirconium/chemistry , Surface Properties , Fluorocarbon Polymers , Phthalic Acids
10.
Int J Mol Sci ; 25(13)2024 Jun 26.
Article in English | MEDLINE | ID: mdl-39000107

ABSTRACT

Even though several new targets (mostly viral infection) for drug repurposing of pyronaridine and artesunate have recently emerged in vitro and in vivo, inter-species pharmacokinetic (PK) data that can extend nonclinical efficacy to humans has not been reported over 30 years of usage. Since extrapolation of animal PK data to those of humans is essential to predict clinical outcomes for drug repurposing, this study aimed to investigate inter-species PK differences in three animal species (hamster, rat, and dog) and to support clinical translation of a fixed-dose combination of pyronaridine and artesunate. PK parameters (e.g., steady-state volume of distribution (Vss), clearance (CL), area under the concentration-time curve (AUC), mean residence time (MRT), etc.) of pyronaridine, artesunate, and dihydroartemisinin (an active metabolite of artesunate) were determined by non-compartmental analysis. In addition, one- or two-compartment PK modeling was performed to support inter-species scaling. The PK models appropriately described the blood concentrations of pyronaridine, artesunate, and dihydroartemisinin in all animal species, and the estimated PK parameters in three species were integrated for inter-species allometric scaling to predict human PKs. The simple allometric equation (Y = a × Wb) well explained the relationship between PK parameters and the actual body weight of animal species. The results from the study could be used as a basis for drug repurposing and support determining the effective dosage regimen for new indications based on in vitro/in vivo efficacy data and predicted human PKs in initial clinical trials.


Subject(s)
Artemisinins , Artesunate , Drug Repositioning , Naphthyridines , Artesunate/pharmacokinetics , Artesunate/pharmacology , Drug Repositioning/methods , Animals , Rats , Dogs , Naphthyridines/pharmacokinetics , Naphthyridines/pharmacology , Artemisinins/pharmacokinetics , Species Specificity , Humans , Models, Biological , Male , Antimalarials/pharmacokinetics , Antimalarials/pharmacology
11.
Antimicrob Agents Chemother ; 68(9): e0085324, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39058023

ABSTRACT

Plasmodium vivax is now the main cause of malaria outside Africa. The gametocytocidal effects of antimalarial drugs are important to reduce malaria transmissibility, particularly in low-transmission settings, but they are not well characterized for P. vivax. The transmission-blocking effects of chloroquine, artesunate, and methylene blue on P. vivax gametocytes were assessed. Blood specimens were collected from patients presenting with vivax malaria, incubated with or without the tested drugs, and then fed to mosquitos from a laboratory-adapted colony of Anopheles dirus (a major malaria vector in Southeast Asia). The effects on oocyst and sporozoite development were analyzed under a multi-level Bayesian model accounting for assay variability and the heterogeneity of mosquito Plasmodium infection. Artesunate and methylene blue, but not chloroquine, exhibited potent transmission-blocking effects. Gametocyte exposures to artesunate and methylene blue reduced the mean oocyst count 469-fold (95% CI: 345 to 650) and 1,438-fold (95% CI: 970 to 2,064), respectively. The corresponding estimates for the sporozoite stage were a 148-fold reduction (95% CI: 61 to 470) and a 536-fold reduction (95% CI: 246 to 1,311) in the mean counts, respectively. In contrast, high chloroquine exposures reduced the mean oocyst count only 1.40-fold (95% CI: 1.20 to 1.64) and the mean sporozoite count 1.34-fold (95% CI: 1.12 to 1.66). This suggests that patients with vivax malaria often remain infectious to anopheline mosquitos after treatment with chloroquine. Use of artemisinin combination therapies or immediate initiation of primaquine radical cure should reduce the transmissibility of P. vivax infections.


Subject(s)
Anopheles , Antimalarials , Artesunate , Chloroquine , Malaria, Vivax , Methylene Blue , Plasmodium vivax , Methylene Blue/pharmacology , Methylene Blue/therapeutic use , Artesunate/pharmacology , Artesunate/therapeutic use , Chloroquine/pharmacology , Chloroquine/therapeutic use , Plasmodium vivax/drug effects , Antimalarials/pharmacology , Antimalarials/therapeutic use , Malaria, Vivax/drug therapy , Malaria, Vivax/parasitology , Malaria, Vivax/transmission , Animals , Humans , Anopheles/parasitology , Anopheles/drug effects , Sporozoites/drug effects , Artemisinins/pharmacology , Artemisinins/therapeutic use , Oocysts/drug effects
12.
Antimicrob Agents Chemother ; 68(9): e0004424, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39046237

ABSTRACT

The emergence and spread of chloroquine-resistant Plasmodium vivax have necessitated the assessment of alternative blood schizonticidal drugs. In Vietnam, chloroquine-resistant P. vivax malaria has been reported. In an open-label, single-arm trial, the safety, tolerability, and efficacy of pyronaridine-artesunate (Pyramax, PA) was evaluated in Dak Nong province, Vietnam. A 3-day course of PA was administered to adults and children (≥20 kg) infected with P. vivax. Patients also received primaquine (0.25 mg/kg daily for 14 days). PA was well tolerated with transient asymptomatic increases in liver transaminases. The per-protocol proportion of patients with day 42 PCR-unadjusted adequate clinical and parasitological response was 96.0% (95% CI, 84.9%-99.0%, n = 48/50). The median parasite clearance time was 12 h (range, 12-36 h), with a median fever clearance time of 24 h (range, 12-60 h). Single nucleotide polymorphisms (SNPs) as potential genetic markers of reduced drug susceptibility were analyzed in three putative drug resistance markers, Pvcrt-o, Pvmdr1, and PvK12. Insertion at position K10 of the Pvcrt-o gene was found in 74.6% (44/59) of isolates. Pvmdr1 SNPs at Y976F and F1076L were present in 61% (36/59) and 78% (46/59), respectively. Amplification of Pvmdr1 gene (two copies) was found in 5.1% (3/59) of parasite samples. Only 5.1% (3/59) of isolates had mutation 552I of the PvK12 gene. Overall, PA rapidly cleared P. vivax blood asexual stages and was highly efficacious in treating vivax malaria, with no evidence of artemisinin resistance found. PA provides an alternative to chloroquine treatment for vivax malaria in Vietnam. CLINICAL TRIALS: This study is registered with the Australian New Zealand Clinical Trials Registry as ACTRN12618001429246.


Subject(s)
Antimalarials , Artemisinins , Artesunate , Malaria, Vivax , Naphthyridines , Plasmodium vivax , Humans , Malaria, Vivax/drug therapy , Malaria, Vivax/parasitology , Naphthyridines/therapeutic use , Antimalarials/therapeutic use , Artesunate/therapeutic use , Vietnam , Adult , Plasmodium vivax/drug effects , Plasmodium vivax/genetics , Male , Artemisinins/therapeutic use , Adolescent , Child , Female , Middle Aged , Young Adult , Primaquine/therapeutic use , Polymorphism, Single Nucleotide/genetics , Child, Preschool , Protozoan Proteins/genetics , Drug Resistance/genetics , Membrane Transport Proteins
13.
Antimicrob Agents Chemother ; 68(8): e0165923, 2024 Aug 07.
Article in English | MEDLINE | ID: mdl-39028193

ABSTRACT

Artemisinin-based combination therapies (ACTs) were introduced as the standard of care for uncomplicated malaria in Africa almost two decades ago. Recent studies in East Africa have reported a gradual increase in kelch13 (k13) mutant parasites associated with reduced artesunate efficacy. As part of the Community Access to Rectal Artesunate for Malaria project, we collected blood samples from 697 children with signs of severe malaria in northern Uganda between 2018 and 2020, before and after the introduction of rectal artesunate (RAS) in 2019. K13 polymorphisms were assessed, and parasite editing and phenotyping were performed to assess the impact of mutations on parasite resistance. Whole-genome sequencing was performed, and haplotype networks were constructed to determine the geographic origin of k13 mutations. Of the 697 children, 540 were positive for Plasmodium falciparum malaria by PCR and were treated with either RAS or injectable artesunate monotherapy followed in most cases by ACT. The most common k13 mutation was C469Y (6.7%), which was detected more frequently in samples collected after RAS introduction. Genome editing confirmed reduced in vitro susceptibility to artemisinin in C469Y-harboring parasites compared to wild-type controls (P < 0.001). The haplotypic network showed that flanking regions of the C469Y mutation shared the same African genetic background, suggesting a single and indigenous origin of the mutation. Our data provide evidence of selection for the artemisinin-resistant C469Y mutation. The realistic threat of multiresistant parasites emerging in Africa should encourage careful monitoring of the efficacy of artemisinin derivatives and strict adherence to ACT treatment regimens.


Subject(s)
Antimalarials , Artemisinins , Drug Resistance , Malaria, Falciparum , Plasmodium falciparum , Protozoan Proteins , Plasmodium falciparum/drug effects , Plasmodium falciparum/genetics , Uganda , Artemisinins/therapeutic use , Artemisinins/pharmacology , Humans , Antimalarials/therapeutic use , Antimalarials/pharmacology , Malaria, Falciparum/drug therapy , Malaria, Falciparum/parasitology , Drug Resistance/genetics , Protozoan Proteins/genetics , Mutation , Artesunate/therapeutic use , Artesunate/pharmacology , Child, Preschool , Child , Male , Female
14.
Int J Biol Macromol ; 277(Pt 1): 134099, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39048008

ABSTRACT

The laboratory standard MRSA strain WHO-2 and clinical isolate S1 were used to establish a pneumonia infection model. The results showed that methicillin increased the expression of Hla and PVL protein at subminimum inhibitory concentration, while artesunate decreased the secretion of Hla and PVL protein. Artesunate alone reduced hemolysin expression and reversed methicillin-induced increases in Hla and PVL proteins. In addition, the study found that the combination of artesunate and methicillin had the best therapeutic effect, with survival rates of 70 % and 40 % at seven days, respectively (corresponding to the WHO-2 and S1 strains). The combination treatment was able to reduce cell mortality, showing a 65 % and 46 % reduction in cell mortality, respectively. The study also found that the combination therapy decreased the expression of alpha-hemolysin and pantone valentin leukin in the culture medium and significantly reduced the activation of NF-kB. This is caused by a significant decrease in the expression of inflammatory factors.


Subject(s)
Artesunate , Animals , Artesunate/pharmacology , Artesunate/therapeutic use , Mice , Pneumonia, Staphylococcal/drug therapy , Pneumonia, Staphylococcal/microbiology , Staphylococcus aureus/drug effects , Hemolysin Proteins , Methicillin-Resistant Staphylococcus aureus/drug effects , Disease Models, Animal
15.
J Korean Med Sci ; 39(22): e186, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38859743

ABSTRACT

Herein, we report a case of uncomplicated falciparum malaria with late parasitological failure in a 45-year-old businessman returning from Ghana. The patient visited the emergency department with high fever, headache, and dizziness. He traveled without antimalarial chemoprophylaxis. Laboratory tests led to the diagnosis of uncomplicated falciparum malaria with an initial density of 37,669 parasites per µL of blood (p/µL). The patient was treated with intravenous artesunate followed by atovaquone/proguanil. He was discharged with improved condition and decreased parasite density of 887 p/µL. However, at follow-up, parasite density increased to 7,630 p/µL despite the absence of any symptoms. Suspecting treatment failure, the patient was administered intravenous artesunate and doxycycline for seven days and then artemether/lumefantrine for three days. Blood smear was negative for asexual parasitemia after re-treatment but positive for gametocytemia until day 101 from the initial diagnosis. Overall, this case highlights the risk of late parasitological failure in patients with imported uncomplicated falciparum malaria.


Subject(s)
Antimalarials , Atovaquone , Malaria, Falciparum , Plasmodium falciparum , Proguanil , Humans , Malaria, Falciparum/drug therapy , Malaria, Falciparum/diagnosis , Ghana , Antimalarials/therapeutic use , Middle Aged , Male , Plasmodium falciparum/isolation & purification , Proguanil/therapeutic use , Atovaquone/therapeutic use , Travel , Artemisinins/therapeutic use , Artesunate/therapeutic use , Parasitemia/drug therapy , Parasitemia/diagnosis , Doxycycline/therapeutic use , Drug Combinations , Treatment Failure , Artemether, Lumefantrine Drug Combination/therapeutic use
16.
Antimicrob Agents Chemother ; 68(7): e0033824, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38837364

ABSTRACT

The human malaria-Aotus monkey model has served the malaria research community since its inception in 1966 at the Gorgas Memorial Laboratory (GML) in Panama. Spanning over five decades, this model has been instrumental in evaluating the in vivo efficacy and pharmacokinetics of a wide array of candidate antimalarial drugs, whether used singly or in combination. The animal model could be infected with drug-resistant and susceptible Plasmodium falciparum and Plasmodium vivax strains that follow a characteristic and reproducible course of infection, remarkably like human untreated and treated infections. Over the years, the model has enabled the evaluation of several synthetic and semisynthetic endoperoxides, for instance, artelinic acid, artesunate, artemether, arteether, and artemisone. These compounds have been evaluated alone and in combination with long-acting partner drugs, commonly referred to as artemisinin-based combination therapies, which are recommended as first-line treatment against uncomplicated malaria. Further, the model has also supported the evaluation of the primaquine analog tafenoquine against blood stages of P. vivax, contributing to its progression to clinical trials and eventual approval. Besides, the P. falciparum/Aotus model at GML has also played a pivotal role in exploring the biology, immunology, and pathogenesis of malaria and in the characterization of drug-resistant P. falciparum and P. vivax strains. This minireview offers a historical overview of the most significant contributions made by the Panamanian owl monkey (Aotus lemurinus lemurinus) to malaria chemotherapy research.


Subject(s)
Antimalarials , Artemisinins , Disease Models, Animal , Animals , Antimalarials/therapeutic use , Antimalarials/pharmacokinetics , Antimalarials/pharmacology , Artemisinins/therapeutic use , Artemisinins/pharmacology , Humans , Panama , Aotidae , Plasmodium falciparum/drug effects , Malaria/drug therapy , Plasmodium vivax/drug effects , Malaria, Falciparum/drug therapy , Malaria, Falciparum/parasitology , Artesunate/therapeutic use , Artesunate/pharmacology , Artesunate/pharmacokinetics , Malaria, Vivax/drug therapy , Malaria, Vivax/parasitology , History, 20th Century , Aminoquinolines
17.
Malar J ; 23(1): 178, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38840266

ABSTRACT

BACKGROUND: Neonatal malaria is defined as the detection of asexual stages of Plasmodium species in the cord blood within the first 28 days of life. It can be congenital or acquired through mosquito bites or blood transfusions. Neonates are generally considered to be relatively protected due to the multiple innate and acquired physiological protective effects present in neonates. However, in areas where malaria is endemic, the prevalence of malaria in neonates is high. The predominant clinical feature of malaria in neonates is fever. Other clinical manifestations of neonatal malaria include respiratory distress, pallor and anaemia, hepatomegaly, refusal to feed, jaundice and diarrhoea. Atypical presentations without fever can lead to inaccurate diagnosis and contribute to neonatal morbidity and mortality. Neonates from endemic areas with any of the above symptoms should be screened for malaria. CASE PRESENTATION: We present a series of three cases of neonatal Plasmodium falciparum malaria that presented atypically without febrile episodes and were diagnosed and managed at Mizan-Tepi University Teaching Hospital between July and September 2023. The first patient presented with vomiting, refusal to feed, pallor, severe anaemia, and splenomegaly. The second patient presented with an inconsolable cry, failure to pass feces, abdominal distention, and anaemia. The third patient presented with vomiting and anaemia. All patients received a 7-day course of intravenous artesunate; the first patient also received a blood transfusion. All patients recovered and were discharged. CONCLUSIONS: Partial immunity resulting from repeated malaria infections in endemic regions may result in the transfer of high levels of maternal Immunoglobulin G (IgG) antibodies through the placenta and can produce different atypical clinical presentations. In malaria-endemic areas, neonates presenting with any of the presenting signs and symptoms of malaria, including afebrile presentation, require malaria screening to avoid delays in diagnosis.


Subject(s)
Malaria, Falciparum , Female , Humans , Infant, Newborn , Male , Antimalarials/therapeutic use , Artesunate/therapeutic use , Ethiopia , Malaria, Falciparum/diagnosis , Plasmodium falciparum/isolation & purification
18.
Int J Biol Macromol ; 273(Pt 2): 133220, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38897506

ABSTRACT

Artemisinin and its derivatives have been commonly used to treat malaria. However, the emergence of resistance against artemisinin derivatives has posed a critical challenge in malaria management. In the present study, we have proposed a combinatorial approach, utilizing pH-responsive acetal-dextran nanoparticles (Ac-Dex NPs) as carriers for the delivery of withaferin-A (WS-3) and artesunate (Art) to improve treatment efficacy of malaria. The optimized WS-3 and Art Ac-Dex NPs demonstrated enhanced pH-responsive release profiles under parasitophorous mimetic conditions (pH 5.5). Computational molecular modeling reveals that Ac-Dex's polymeric backbone strongly interacts with merozoite surface protein-1 (MSP-1), preventing erythrocyte invasion. In-vitro antimalarial activity of drug-loaded Ac-Dex NPs reveals a 1-1.5-fold reduction in IC50 values compared to pure drug against the 3D7 strain of Plasmodium falciparum. Treatment with WS-3 Ac-Dex NPs (100 mg/kg) and Art Ac-Dex NPs (30 mg/kg) to Plasmodium berghei-infected mice resulted in 78.11 % and 100 % inhibition of parasitemia. Notably, the combination therapy comprised of Art and WS-3 Ac-Dex NPs achieved complete inhibition of parasitemia even at a half dose of Art, indicating the synergistic potential of the combinations. However, further investigations are necessary to confirm the safety and effectiveness of WS-3 and Art Ac-Dex NPs for their successful clinical implications.


Subject(s)
Antimalarials , Artesunate , Dextrans , Malaria , Nanoparticles , Withanolides , Artesunate/chemistry , Artesunate/pharmacology , Artesunate/therapeutic use , Nanoparticles/chemistry , Animals , Antimalarials/chemistry , Antimalarials/pharmacology , Antimalarials/therapeutic use , Hydrogen-Ion Concentration , Mice , Dextrans/chemistry , Malaria/drug therapy , Withanolides/chemistry , Withanolides/pharmacology , Drug Carriers/chemistry , Plasmodium berghei/drug effects , Plasmodium falciparum/drug effects , Artemisinins/pharmacology , Artemisinins/chemistry , Drug Liberation , Polymers/chemistry
19.
Eur J Pharmacol ; 977: 176709, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38843948

ABSTRACT

Cardiac Hypertrophy is an adaptive response of the body to physiological and pathological stimuli, which increases cardiomyocyte size, thickening of cardiac muscles and progresses to heart failure. Downregulation of SIRT1 in cardiomyocytes has been linked with the pathogenesis of cardiac hypertrophy. The present study aimed to investigate the effect of Artesunate against isoprenaline induced cardiac hypertrophy in rats via SIRT1 inhibiting NF-κB activation. Experimental cardiac hypertrophy was induced in rats by subcutaneous administration of isoprenaline (5 mg/kg) for 14 days. Artesunate was administered simultaneously for 14 days at a dose of 25 mg/kg and 50 mg/kg. Artesunate administration showed significant dose dependent attenuation in mean arterial pressure, electrocardiogram, hypertrophy index and left ventricular wall thickness compared to the disease control group. It also alleviated cardiac injury biomarkers and oxidative stress. Histological observation showed amelioration of tissue injury in the artesunate treated groups compared to the disease control group. Further, artesunate treatment increased SIRT1 expression and decreased NF-kB expression in the heart. The results of the study show the cardioprotective effect of artesunate via SIRT1 inhibiting NF-κB activation in cardiomyocytes.


Subject(s)
Artesunate , Cardiomegaly , Isoproterenol , NF-kappa B , Sirtuin 1 , Animals , Artesunate/pharmacology , Artesunate/therapeutic use , Sirtuin 1/metabolism , Isoproterenol/toxicity , NF-kappa B/metabolism , Male , Cardiomegaly/chemically induced , Cardiomegaly/drug therapy , Cardiomegaly/pathology , Cardiomegaly/prevention & control , Rats , Oxidative Stress/drug effects , Artemisinins/pharmacology , Artemisinins/therapeutic use , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology , Cardiotonic Agents/pharmacology , Cardiotonic Agents/therapeutic use , Rats, Sprague-Dawley
20.
Biomed Pharmacother ; 177: 116885, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38878633

ABSTRACT

Sjögren's syndrome (SS) is an autoimmune disease in which the salivary glands (SGs) and the lacrimal glands (LGs) are affected by lymphocytic infiltration and inflammation. It has been reported that interferon-α (IFN-α) released by plasmacytoid dendritic cells (pDCs) contribute to the pathology of SS, and ART has been shown to effectively ameliorates SS. Despite the current research endeavors, the mechanism of how ART works in the treatment of SS remains to be fully elucidated. Whether ART can treat SS by inhibiting IFN-α remains unclear. This hypothesis was tested both in vivo and in vitro settings during the study. The SS model mice, which were treated with ART, showed amelioration in symptoms related to dryness. RNA-seq analysis revealed strong anti-IFN-α signaling response upon ART treatment. Additional in vitro studies provided further confirmation that the application of ART inhibits the MyD88 protein expression and the nuclear translocation of IRF7. This suggests that the intervention of ART in the TLR-MyD88-IRF7 pathway plays a role in the therapeutic approach for SS. In summary, this study highlighted the therapeutic potential of ART in SS and ART inhibited the IFN-α signaling in pDCs via the TLR-MyD88-IRF7 pathway.


Subject(s)
Artesunate , Dendritic Cells , Interferon Regulatory Factor-7 , Interferon-alpha , Mice, Inbred C57BL , Myeloid Differentiation Factor 88 , Signal Transduction , Sjogren's Syndrome , Animals , Sjogren's Syndrome/drug therapy , Sjogren's Syndrome/metabolism , Dendritic Cells/drug effects , Dendritic Cells/metabolism , Myeloid Differentiation Factor 88/metabolism , Interferon-alpha/metabolism , Interferon-alpha/pharmacology , Signal Transduction/drug effects , Interferon Regulatory Factor-7/metabolism , Mice , Artesunate/pharmacology , Artesunate/therapeutic use , Toll-Like Receptors/metabolism , Female , Disease Models, Animal
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