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1.
AAPS J ; 26(5): 91, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39107504

RESUMEN

Repurposing drugs offers several advantages, including reduced time and cost compared to developing new drugs from scratch. It leverages existing knowledge about drug safety, dosage, and pharmacokinetics, expediting the process of clinical trials and regulatory approval. Dihydroartemisinin (DHA) is a semi-synthetic and active metabolite of all artemisinin molecules and is FDA-approved for the treatment of malaria. Apart from having anti-malarial properties, DHA also possesses anticancer properties. However, its pharmacological actions are limited by toxicity and solubility problems. To overcome these challenges and enhance its anticancer effectiveness, we designed an exosomal formulation of DHA. We isolated exosomes from bovine milk using differential ultracentrifugation and loaded DHA using sonication. Scanning and transition electron microscopy revealed a size of roughly 100 nm, with a spherical shape. Furthermore, in pH 7.4 and 5.5, the exosomes exhibited burst release followed by sustained release. Multiple in vitro cell culture tests demonstrated that Exo-DHA exhibited enhanced anticancer activity, including cytotoxicity, cellular uptake, generation of reactive oxygen species (ROS), disruption of mitochondrial membrane potential, and inhibition of colony formation. Additional evidence supporting Exo-DHA's anti-migration ability came from transwell migration and scratch assays. Based on these results, it was concluded that the anticancer efficacy of DHA was improved when loaded into bovine milk-derived exosomes. While the in vitro results are encouraging, more in vivo testing in suitable animal models and biochemical marker analysis are warranted.


Asunto(s)
Antineoplásicos , Artemisininas , Exosomas , Leche , Neoplasias de la Mama Triple Negativas , Artemisininas/farmacología , Artemisininas/administración & dosificación , Artemisininas/química , Animales , Leche/química , Bovinos , Humanos , Antineoplásicos/farmacología , Antineoplásicos/administración & dosificación , Línea Celular Tumoral , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Especies Reactivas de Oxígeno/metabolismo , Femenino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos
2.
BMC Pharmacol Toxicol ; 25(1): 38, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38978151

RESUMEN

BACKGROUND: Dihydroartemisinin-piperaquine (DHP) recently showed superior effectiveness over sulfadoxine-pyrimethamine for malaria intermittent preventive treatment in pregnancy (IPTp). We investigated day 7 piperaquine pharmacokinetics and its therapeutic efficacy in preventing malaria during pregnancy. METHODS: Malaria-free (mRDT) pregnant women (n = 400) who received monthly IPTp-DHP were enrolled and followed till delivery. Day 7 Plasma piperaquine concentrations were determined after each IPTp dose using UPLC/MS/MS. IPTp outcomes (symptomatic malaria and parasitemia during pregnancy, placental malaria, and maternal malaria at delivery) were monitored. Linear mixed model and Cox regression were used to assess predictors of day 7 piperaquine concentration and treatment outcome, respectively. RESULTS: The incidences of symptomatic malaria and parasitemia during pregnancy per 100 person-year at risk were 2 and 33, respectively. The prevalence of histopathologically confirmed placental malaria and maternal malaria at delivery were 3% and 9.8%, respectively. Repeated monthly IPTp-DHP resulted in significantly increased day 7 plasma piperaquine concentration (p < 0.001). Following the 1st, 2nd, and 3rd monthly IPTp-DHP doses, the proportions of women with day 7 piperaquine concentration below the therapeutic threshold (< 30 ng/mL) were 6.1%, 4.1% and 3.6%, respectively. Factors such as maternal age, body weight and trimester were not significant predictors of day 7 piperaquine concentration. However, having a low day 7 piperaquine plasma concentration (< 30 ng/mL) was significantly associated with a higher risk of parasitemia during pregnancy (p = 0.004). CONCLUSION: Lower day 7 piperaquine plasma concentration is a risk factor for parasitemia during pregnancy. Single plasma sampling at day 7 can be used to monitor piperaquine effectiveness during IPTp-DHP. TRIAL REGISTRATION: Registered 09/12/2016, PACTR201612001901313.


Asunto(s)
Antimaláricos , Malaria , Complicaciones Parasitarias del Embarazo , Quinolinas , Humanos , Femenino , Embarazo , Quinolinas/farmacocinética , Quinolinas/sangre , Quinolinas/uso terapéutico , Quinolinas/administración & dosificación , Antimaláricos/farmacocinética , Antimaláricos/uso terapéutico , Antimaláricos/sangre , Antimaláricos/administración & dosificación , Adulto , Complicaciones Parasitarias del Embarazo/prevención & control , Complicaciones Parasitarias del Embarazo/sangre , Adulto Joven , Malaria/prevención & control , Malaria/tratamiento farmacológico , Artemisininas/farmacocinética , Artemisininas/uso terapéutico , Artemisininas/administración & dosificación , Artemisininas/sangre , Parasitemia/sangre , Parasitemia/prevención & control , Resultado del Tratamiento , Combinación de Medicamentos , Adolescente , Piperazinas
3.
Malar J ; 23(1): 208, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38997771

RESUMEN

BACKGROUND: To interrupt residual malaria transmission and achieve successful elimination of Plasmodium falciparum in low-transmission settings, the World Health Organization (WHO) recommends the administration of a single dose of 0.25 mg/kg (or 15 mg/kg for adults) primaquine (PQ) combined with artemisinin-based combination therapy (ACT), without glucose-6-phosphate dehydrogenase (G6PD) testing. However, due to the risk of haemolysis in patients with G6PD deficiency (G6PDd), PQ use is uncommon. Thus, this study aimed to assess the safety of a single low dose of PQ administered to patients with G6PD deficiency. METHODS: An observational cohort study was conducted with patients treated for uncomplicated P. falciparum malaria with either single-dose PQ (0.25 mg/kg) (SLD PQ) + ACT or ACT alone. Microscopy-confirmed uncomplicated P. falciparum malaria patients visiting public health facilities in Arjo Didessa, Southwest Ethiopia, were enrolled in the study from September 2019 to November 2022. Patients with uncomplicated P. falciparum malaria were followed up for 28 days through clinical and laboratory diagnosis, such as measurements of G6PD levels and haemoglobin (Hb) concentrations. G6PD levels were measured by a quantiative CareSTART™ POCT S1 biosensor machine. Patient interviews were also conducted, and the type and frequency of clinical complaints were recorded. Hb data were taken on days (D) 7, 14, 21, and 28 following treatment with SLD-PQ + ACT or ACT alone. RESULTS: A total of 249 patients with uncomplicated P. falciparum malaria were enrolled in this study. Of these, 83 (33.3%) patients received ACT alone, and 166 (66.7%) received ACT combined with SLD-PQ treatment. The median age of the patients was 20 (IQR 28-15) years. G6PD deficiency was found in 17 (6.8%) patients, 14 males and 3 females. There were 6 (7.2%) and 11 (6.6%) phenotypic G6PD-deficient patients in the ACT alone and ACT + SLD-PQ arms, respectively. The mean Hb levels in patients treated with ACT + SLD-PQ were reduced by an average of 0.45 g/dl (95% CI = 0.39 to 0.52) in the posttreatment phase (D7) compared to a reduction of 0.30 g/dl (95% CI = 0.14 to - 0.47) in patients treated with ACT alone (P = 0.157). A greater mean Hb reduction was observed on day 7 in the G6PDd ACT + SLD-PQ group (- 0.60 g/dL) than in the G6PDd ACT alone group (- 0.48 g/dL); however, there was no statistically significant difference (P = 0.465). Overall, D14 losses were 0.10 g/dl (95% CI = - 0.00 to 0.20) and 0.05 g/dl (95% CI = - 0.123 to 0.22) in patients with and without SLD-PQ, respectively (P = 0.412). CONCLUSIONS: This study's findings indicate that using SLD-PQ in combination with ACT is safe for uncomplicated P. falciparum malaria regardless of the patient's G6PD status in Ethiopian settings. Caution should be taken in extrapolating this finding in other settings with diverse G6DP phenotypes.


Asunto(s)
Antimaláricos , Artemisininas , Deficiencia de Glucosafosfato Deshidrogenasa , Hemoglobinas , Malaria Falciparum , Primaquina , Malaria Falciparum/tratamiento farmacológico , Humanos , Etiopía , Masculino , Primaquina/administración & dosificación , Primaquina/uso terapéutico , Primaquina/efectos adversos , Adulto , Antimaláricos/administración & dosificación , Antimaláricos/uso terapéutico , Femenino , Estudios Longitudinales , Hemoglobinas/análisis , Adolescente , Adulto Joven , Deficiencia de Glucosafosfato Deshidrogenasa/complicaciones , Persona de Mediana Edad , Niño , Artemisininas/administración & dosificación , Artemisininas/uso terapéutico , Estudios de Cohortes , Preescolar , Plasmodium falciparum/efectos de los fármacos
4.
Colloids Surf B Biointerfaces ; 241: 113992, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38833960

RESUMEN

In order to reduce the cardiotoxicity of doxorubicin (DOX) and improve its antitumor effect, dihydroartemisinin (DHA) and DOX prodrug (DOX-S-DHA) synthesized via a single sulfur bond was used with TEPP-46 to prepare nano-liposomes (DOX-S-DHA@TEPP-46 Lips). In which, TEPP-46 was expected to exert p53 bidirectional regulation to promote the synergistic antitumor effect of DOX and DHA while reducing cardiotoxicity. DOX-S-DHA@TEPP-46 Lips exhibited uniform particle size, good stability, and excellent redox-responsive activity. DOX-S-DHA@TEPP-46 Lips could significantly inhibit the proliferation of tumor cells, but had less cytotoxicity on normal cells. The presence of TEPP-46 increased the content of p53 protein, which further induced tumor cell apoptosis. DOX-S-DHA@TEPP-46 Lips had satisfactory long circulation to enhance the antitumor efficacy and reversed the cardiotoxicity of DOX in B16-F10 tumor-bearing mice. In conclusion, DOX-S-DHA@TEPP-46 Lips provides a new insight on creating sophisticated redox-sensitive nano-liposomes for cancer therapy as well as the decreased cardiotoxicity of DOX.


Asunto(s)
Artemisininas , Cardiotoxicidad , Doxorrubicina , Liposomas , Profármacos , Animales , Artemisininas/química , Artemisininas/farmacología , Artemisininas/administración & dosificación , Doxorrubicina/farmacología , Doxorrubicina/química , Doxorrubicina/administración & dosificación , Profármacos/química , Profármacos/farmacología , Ratones , Liposomas/química , Cardiotoxicidad/prevención & control , Proliferación Celular/efectos de los fármacos , Apoptosis/efectos de los fármacos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/administración & dosificación , Tamaño de la Partícula , Nanopartículas/química , Sistemas de Liberación de Medicamentos , Ratones Endogámicos C57BL , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/patología , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Línea Celular Tumoral
5.
Int J Pharm ; 660: 124330, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-38866081

RESUMEN

Chemodynamic therapy (CDT) is a promising strategy for cancer treatment, however, its application is restricted by low hydrogen peroxide (H2O2) concentration, insufficient reactive oxygen species (ROS) generation, and high glutathione (GSH) levels. Here, we developed an injectable thermosensitive hydrogel (DSUC-Gel) based on "sea urchin-like" copper sulfide nanoparticles (UCuS) loaded with dihydroartemisinin (DHA) and sulfasalazine (SAS) to overcome these limitations of CDT. DSUC was cleaved to release DHA, SAS and Cu2+ under acidic tumor microenvironment to enhance CDT. DHA with peroxide bridge responded to intracellular Fe2+ to alleviate H2O2 deficiency. SAS prevented GSH synthesis by targeting SLC7A11 and inhibited glutathione peroxidase (GPX4) activity to induce endogenous ferroptosis. ROS produced by Fenton-like reaction of Cu2+ promoted lipid peroxidation (LPO) accumulation to promote ferroptosis. Enhanced CDT and ferroptosis induced immunogenic cell death (ICD), promoted dendritic cells (DCs) maturation and cytotoxic T lymphocytes (CTLs) infiltration. As a result, DSUC-Gel significantly inhibited tumor growth both in vitro and in vivo. Our study provides a novel approach for enhancing anti-tumor efficacy by combining CDT, endogenous ferroptosis and ICD.


Asunto(s)
Artemisininas , Cobre , Ferroptosis , Hidrogeles , Especies Reactivas de Oxígeno , Sulfasalazina , Ferroptosis/efectos de los fármacos , Animales , Cobre/química , Ratones , Especies Reactivas de Oxígeno/metabolismo , Artemisininas/farmacología , Artemisininas/administración & dosificación , Artemisininas/química , Línea Celular Tumoral , Sulfasalazina/farmacología , Sulfasalazina/administración & dosificación , Humanos , Sulfuros/farmacología , Sulfuros/administración & dosificación , Sulfuros/química , Nanopartículas , Microambiente Tumoral/efectos de los fármacos , Antineoplásicos/farmacología , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Peroxidación de Lípido/efectos de los fármacos , Femenino , Peróxido de Hidrógeno , Glutatión/metabolismo , Ratones Endogámicos BALB C
6.
Parasit Vectors ; 17(1): 279, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38943214

RESUMEN

BACKGROUND: Reliance on praziquantel for the treatment and control of schistosomiasis is likely to facilitate the emergence of drug resistance. Combination therapy targeting adult and juvenile schistosome worms is urgently needed to improve praziquantel efficacy and delay the potential development of drug resistance. We assessed the efficacy and safety of single-dose praziquantel combined with single-dose artesunate plus sulfalene-pyrimethamine in the treatment of Kenyan children with schistosomiasis. METHODS: This was an open-label, randomised clinical trial involving 426 school-aged children (7-15 years old) diagnosed with Schistosoma mansoni (by Kato-Katz) or S. haematobium (by urine filtration). They were randomly assigned (1:1:1) to receive a single dose of praziquantel (40 mg/kg), a single dose of artesunate plus sulfalene-pyrimethamine (12 mg/kg artesunate) or combination therapy using a single dose of praziquantel (40 mg/kg) combined with a single dose of artesunate plus sulfalene-pyrimethamine (12 mg/kg artesunate). The primary outcome was cure and egg reduction rates at 6 weeks post-treatment in the available case population. Adverse events were assessed within 3 h after treatment. RESULTS: Of the 426 children enrolled, 135 received praziquantel, 150 received artesunate plus sulfalene-pyrimethamine, and 141 received combination therapy. Outcome data were available for 348 (81.7%) children. For S. mansoni-infected children (n = 335), the cure rates were 75.6%, 60.7%, and 77.8%, and the egg reduction rates were 80.1%, 85.0%, and 88.4% for praziquantel, artesunate plus sulfalene-pyrimethamine, and combination therapy, respectively. For S. haematobium-infected children (n = 145), the corresponding cure rates were 81.4%, 71.1%, and 82.2%, and the egg reduction rates were 95.6%, 97.1%, and 97.7%, respectively. Seventy-one (16.7%) children reported mild-intensity adverse events. The drugs were well tolerated and no serious adverse events were reported. CONCLUSIONS: A single oral dose of praziquantel combined with artesunate plus sulfalene-pyrimethamine cured a high proportion of children with S. haematobium but did not significantly improve the treatment efficacy for either urinary or intestinal schistosomiasis. Sequential administration of praziquantel and artesunate plus sulfalene-pyrimethamine may enhance the efficacy and safety outcomes.


Asunto(s)
Antihelmínticos , Artemisininas , Artesunato , Quimioterapia Combinada , Praziquantel , Pirimetamina , Schistosoma haematobium , Schistosoma mansoni , Esquistosomiasis Urinaria , Esquistosomiasis mansoni , Humanos , Niño , Praziquantel/administración & dosificación , Praziquantel/efectos adversos , Praziquantel/uso terapéutico , Pirimetamina/administración & dosificación , Pirimetamina/uso terapéutico , Pirimetamina/efectos adversos , Animales , Adolescente , Artesunato/administración & dosificación , Artesunato/uso terapéutico , Femenino , Masculino , Esquistosomiasis mansoni/tratamiento farmacológico , Schistosoma haematobium/efectos de los fármacos , Esquistosomiasis Urinaria/tratamiento farmacológico , Schistosoma mansoni/efectos de los fármacos , Kenia , Artemisininas/administración & dosificación , Artemisininas/uso terapéutico , Artemisininas/efectos adversos , Resultado del Tratamiento , Antihelmínticos/administración & dosificación , Antihelmínticos/efectos adversos , Antihelmínticos/uso terapéutico , Sulfaleno/administración & dosificación , Sulfaleno/uso terapéutico , Sulfaleno/efectos adversos , Combinación de Medicamentos , Recuento de Huevos de Parásitos
7.
Int J Nanomedicine ; 19: 5273-5295, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38859952

RESUMEN

Purpose: Reducing the first-pass hepatic effect via intestinal lymphatic transport is an effective way to increase the oral absorption of drugs. 2-Monoacylglycerol (2-MAG) as a primary digestive product of dietary lipids triglyceride, can be assembled in chylomicrons and then transported from the intestine into the lymphatic system. Herein, we propose a biomimetic strategy and report a 2-MAG mimetic nanocarrier to target the intestinal lymphatic system via the lipid absorption pathway and improve oral bioavailability. Methods: The 2-MAG mimetic liposomes were designed by covalently bonding serinol (SER) on the surface of liposomes named SER-LPs to simulate the structure of 2-MAG. Dihydroartemisinin (DHA) was chosen as the model drug because of its disadvantages such as poor solubility and high first-pass effect. The endocytosis and exocytosis mechanisms were investigated in Caco-2 cells and Caco-2 cell monolayers. The capacity of intestinal lymphatic transport was evaluated by ex vivo biodistribution and in vivo pharmacokinetic experiments. Results: DHA loaded SER-LPs (SER-LPs-DHA) had a particle size of 70 nm and a desirable entrapment efficiency of 93%. SER-LPs showed sustained release for DHA in the simulated gastrointestinal environment. In vitro cell studies demonstrated that the cellular uptake of SER-LPs primarily relied on the caveolae- rather than clathrin-mediated endocytosis pathway and preferred to integrate into the chylomicron assembly process through the endoplasmic reticulum/Golgi apparatus route. After oral administration, SER-LPs efficiently promoted drug accumulation in mesenteric lymphatic nodes. The oral bioavailability of DHA from SER-LPs was 10.40-fold and 1.17-fold larger than that of free DHA and unmodified liposomes at the same dose, respectively. Conclusion: SER-LPs improved oral bioavailability through efficient intestinal lymphatic transport. These findings of the current study provide a good alternative strategy for oral delivery of drugs with high first-pass hepatic metabolism.


Asunto(s)
Artemisininas , Disponibilidad Biológica , Liposomas , Animales , Liposomas/química , Liposomas/farmacocinética , Células CACO-2 , Humanos , Administración Oral , Artemisininas/farmacocinética , Artemisininas/química , Artemisininas/administración & dosificación , Absorción Intestinal/efectos de los fármacos , Masculino , Distribución Tisular , Tamaño de la Partícula , Ratones , Sistema Linfático/metabolismo , Sistema Linfático/efectos de los fármacos , Ratas Sprague-Dawley , Ratas , Materiales Biomiméticos/farmacocinética , Materiales Biomiméticos/química , Mucosa Intestinal/metabolismo
8.
Am J Trop Med Hyg ; 111(1): 43-47, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38806022

RESUMEN

Increasing antimicrobial resistance (AMR) is a global public health emergency. Although chemoprevention has improved malaria-related pregnancy outcomes, the downstream effects on AMR have not been characterized. We compared the abundance of 10 AMR genes in stool samples from pregnant women receiving sulfadoxine-pyrimethamine (SP) as intermittent preventive treatment against malaria in pregnancy (IPTp) to that in samples from women receiving dihydroartemisinin-piperaquine (DP) for IPTp. All participants had at least one AMR gene at baseline. Mean quantities of the antifolate gene dfrA17 were increased after two or more doses of SP (mean difference = 1.6, 95% CI: 0.4-2.7, P = 0.008). Antimicrobial resistance gene abundance tended to increase from baseline in SP recipients compared with a downward trend in the DP group. Overall, IPTp-SP had minimal effects on the abundance of antifolate resistance genes (except for dfrA17), potentially owing to a high starting prevalence. However, the trend toward increasing AMR in SP recipients warrants further studies.


Asunto(s)
Antimaláricos , Artemisininas , Combinación de Medicamentos , Heces , Pirimetamina , Quinolinas , Sulfadoxina , Humanos , Femenino , Pirimetamina/uso terapéutico , Pirimetamina/administración & dosificación , Pirimetamina/farmacología , Sulfadoxina/uso terapéutico , Sulfadoxina/administración & dosificación , Sulfadoxina/farmacología , Embarazo , Antimaláricos/uso terapéutico , Antimaláricos/farmacología , Antimaláricos/administración & dosificación , Quinolinas/uso terapéutico , Quinolinas/administración & dosificación , Artemisininas/uso terapéutico , Artemisininas/farmacología , Artemisininas/administración & dosificación , Adulto , Heces/microbiología , Adulto Joven , Complicaciones Parasitarias del Embarazo/prevención & control , Complicaciones Parasitarias del Embarazo/tratamiento farmacológico , Resistencia a Medicamentos/genética , Malaria Falciparum/prevención & control , Malaria Falciparum/epidemiología , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/genética , Piperazinas
9.
Malar J ; 23(1): 146, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750517

RESUMEN

BACKGROUND: In 2020, during the COVID-19 pandemic, Médecins Sans Frontières (MSF) initiated three cycles of dihydroartemisin-piperaquine (DHA-PQ) mass drug administration (MDA) for children aged three months to 15 years within Bossangoa sub-prefecture, Central African Republic. Coverage, clinical impact, and community members perspectives were evaluated to inform the use of MDAs in humanitarian emergencies. METHODS: A household survey was undertaken after the MDA focusing on participation, recent illness among eligible children, and household satisfaction. Using routine surveillance data, the reduction during the MDA period compared to the same period of preceding two years in consultations, malaria diagnoses, malaria rapid diagnostic test (RDT) positivity in three MSF community healthcare facilities (HFs), and the reduction in severe malaria admissions at the regional hospital were estimated. Twenty-seven focus groups discussions (FGDs) with community members were conducted. RESULTS: Overall coverage based on the MDA card or verbal report was 94.3% (95% confidence interval (CI): 86.3-97.8%). Among participants of the household survey, 2.6% (95% CI 1.6-40.3%) of round 3 MDA participants experienced illness in the preceding four weeks compared to 30.6% (95% CI 22.1-40.8%) of MDA non-participants. One community HF experienced a 54.5% (95% CI 50.8-57.9) reduction in consultations, a 73.7% (95% CI 70.5-76.5) reduction in malaria diagnoses, and 42.9% (95% CI 36.0-49.0) reduction in the proportion of positive RDTs among children under five. A second community HF experienced an increase in consultations (+ 15.1% (- 23.3 to 7.5)) and stable malaria diagnoses (4.2% (3.9-11.6)). A third community HF experienced an increase in consultations (+ 41.1% (95% CI 51.2-31.8) and malaria diagnoses (+ 37.3% (95% CI 47.4-27.9)). There were a 25.2% (95% CI 2.0-42.8) reduction in hospital admissions with severe malaria among children under five from the MDA area. FGDs revealed community members perceived less illness among children because of the MDA, as well as fewer hospitalizations. Other indirect benefits such as reduced household expenditure on healthcare were also described. CONCLUSION: The MDA achieved high coverage and community acceptance. While some positive health impact was observed, it was resource intensive, particularly in this rural context. The priority for malaria control in humanitarian contexts should remain diagnosis and treatment. MDA may be additional tool where the context supports its implementation.


Asunto(s)
Antimaláricos , Artemisininas , COVID-19 , Malaria , Administración Masiva de Medicamentos , Humanos , Antimaláricos/uso terapéutico , Antimaláricos/administración & dosificación , Preescolar , Lactante , Niño , Adolescente , COVID-19/epidemiología , República Centroafricana/epidemiología , Artemisininas/uso terapéutico , Artemisininas/administración & dosificación , Administración Masiva de Medicamentos/estadística & datos numéricos , Femenino , Masculino , Malaria/tratamiento farmacológico , SARS-CoV-2 , Quinolinas/administración & dosificación , Quinolinas/uso terapéutico
10.
Nat Commun ; 15(1): 3817, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714692

RESUMEN

Standard diagnostics used in longitudinal antimalarial studies are unable to characterize the complexity of submicroscopic parasite dynamics, particularly in high transmission settings. We use molecular markers and amplicon sequencing to characterize post-treatment stage-specific malaria parasite dynamics during a 42 day randomized trial of 3- versus 5 day artemether-lumefantrine in 303 children with and without HIV (ClinicalTrials.gov number NCT03453840). The prevalence of parasite-derived 18S rRNA is >70% in children throughout follow-up, and the ring-stage marker SBP1 is detectable in over 15% of children on day 14 despite effective treatment. We find that the extended regimen significantly lowers the risk of recurrent ring-stage parasitemia compared to the standard 3 day regimen, and that higher day 7 lumefantrine concentrations decrease the probability of ring-stage parasites in the early post-treatment period. Longitudinal amplicon sequencing reveals remarkably dynamic patterns of multiclonal infections that include new and persistent clones in both the early post-treatment and later time periods. Our data indicate that post-treatment parasite dynamics are highly complex despite efficacious therapy, findings that will inform strategies to optimize regimens in the face of emerging partial artemisinin resistance in Africa.


Asunto(s)
Antimaláricos , Combinación Arteméter y Lumefantrina , Plasmodium falciparum , Humanos , Combinación Arteméter y Lumefantrina/uso terapéutico , Antimaláricos/uso terapéutico , Antimaláricos/administración & dosificación , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/genética , Preescolar , Niño , Masculino , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/parasitología , Femenino , Parasitemia/tratamiento farmacológico , Parasitemia/parasitología , ARN Ribosómico 18S/genética , Malaria/tratamiento farmacológico , Malaria/parasitología , Lactante , Infecciones por VIH/tratamiento farmacológico , Artemisininas/uso terapéutico , Artemisininas/administración & dosificación
11.
J Anim Sci ; 1022024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38813622

RESUMEN

The aim of this study was to investigate whether dietary dihydroartemisinin (DHA) supplementation could improve intestinal barrier function and microbiota composition in intrauterine growth restriction (IUGR) weaned piglets. Twelve normal birth weight (NBW) piglets and 24 IUGR piglets at 21 d of age were divided into three groups, which were fed a basal diet (NBW-CON and IUCR-CON groups) and an 80 mg/kg DHA diet (IUGR-DHA group). At 49 d of age, eight piglets of each group with similar body weights within groups were slaughtered, and serum and small intestine samples were collected. The results showed that IUGR piglets reduced growth performance, impaired the markers of intestinal permeability, induced intestinal inflammation, decreased intestinal immunity, and disturbed the intestinal microflora. Dietary DHA supplementation increased average daily gain, average daily feed intake, and body weight at 49 d of age in IUGR-weaned piglets (P < 0.05). DHA treatment decreased serum diamine oxidase activity and increased the numbers of intestinal goblet cells and intraepithelial lymphocytes, concentrations of jejunal mucin-2 and ileal trefoil factor 3, and intestinal secretory immunoglobin A and immunoglobin G (IgG) concentrations of IUGR piglets (P < 0.05). Diet supplemented with DHA also upregulated mRNA abundances of jejunal IgG, the cluster of differentiation 8 (CD8), major histocompatibility complex-I (MHC-I), and interleukin 6 (IL-6) and ileal IgG, Fc receptor for IgG (FcRn), cluster of differentiation 8 (CD4), CD8, MHC-I, IL-6 and tumor necrosis factor α (TNF-α), and enhanced mRNA abundance and protein expression of intestinal occludin and ileal claudin-1 in IUGR piglets (P < 0.05). In addition, DHA supplementation in the diet improved the microbial diversity of the small intestine of IUGR piglets and significantly increased the relative abundance of Actinobacteriota, Streptococcus, Blautia and Streptococcus in the jejunum, and Clostridium sensu_ stricto_in the ileum (P < 0.05). The intestinal microbiota was correlated with the mRNA abundance of tight junction proteins and inflammatory response-related genes. These data suggested that DHA could improve the markers of intestinal barrier function in IUGR-weaned piglets by modulating gut microbiota. DHA may be a novel nutritional candidate for preventing intestinal dysfunction in IUGR pigs.


Intrauterine growth retardation (IUGR) is defined as the restricted development of the mammalian fetus or its organs during pregnancy, which has high morbidity and mortality during the perinatal period and improves the risk of metabolic diseases in the long term. Dihydroartemisinin (DHA) is a derivative of artemisinin that possesses anti-inflammatory and immunoregulatory effects. Therefore, this experiment was conducted to investigate whether dietary DHA supplementation could improve the intestinal barrier function and microbiota composition in IUGR-weaned piglets. The result showed that IUGR could lead to intestinal barrier dysfunction. Dietary supplementation with DHA improved growth performance and attenuated intestinal barrier dysfunction by decreasing the markers of intestinal permeability, increasing the mucus layer barrier, enhancing immunity, and reducing the inflammatory response in IUGR piglets, which may be attributed to the improvement of the intestinal microbiota. Moreover, the study indicated that the gut microflora was correlated with the gene expression of tight junction proteins and immune function. This study may provide a new nutritional strategy for the maintenance of intestinal health in IUGR pigs.


Asunto(s)
Alimentación Animal , Artemisininas , Dieta , Suplementos Dietéticos , Retardo del Crecimiento Fetal , Microbioma Gastrointestinal , Destete , Animales , Retardo del Crecimiento Fetal/veterinaria , Microbioma Gastrointestinal/efectos de los fármacos , Porcinos , Dieta/veterinaria , Artemisininas/farmacología , Artemisininas/administración & dosificación , Alimentación Animal/análisis , Enfermedades de los Porcinos/microbiología , Enfermedades de los Porcinos/prevención & control , Intestinos/efectos de los fármacos , Mucosa Intestinal/efectos de los fármacos , Femenino , Funcion de la Barrera Intestinal
12.
Lancet Microbe ; 5(7): 633-644, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38705163

RESUMEN

BACKGROUND: Artemether-lumefantrine is widely used for uncomplicated Plasmodium falciparum malaria; sulfadoxine-pyrimethamine plus amodiaquine is used for seasonal malaria chemoprevention. We aimed to determine the efficacy of artemether-lumefantrine with and without primaquine and sulfadoxine-pyrimethamine plus amodiaquine with and without tafenoquine for reducing gametocyte carriage and transmission to mosquitoes. METHODS: In this phase 2, single-blind, randomised clinical trial conducted in Ouelessebougou, Mali, asymptomatic individuals aged 10-50 years with P falciparum gametocytaemia were recruited from the community and randomly assigned (1:1:1:1) to receive either artemether-lumefantrine, artemether-lumefantrine with a single dose of 0·25 mg/kg primaquine, sulfadoxine-pyrimethamine plus amodiaquine, or sulfadoxine-pyrimethamine plus amodiaquine with a single dose of 1·66 mg/kg tafenoquine. All trial staff other than the pharmacist were masked to group allocation. Participants were not masked to group allocation. Randomisation was done with a computer-generated randomisation list and concealed with sealed, opaque envelopes. The primary outcome was the median within-person percent change in mosquito infection rate in infectious individuals from baseline to day 2 (artemether-lumefantrine groups) or day 7 (sulfadoxine-pyrimethamine plus amodiaquine groups) after treatment, assessed by direct membrane feeding assay. All participants who received any trial drug were included in the safety analysis. This study is registered with ClinicalTrials.gov, NCT05081089. FINDINGS: Between Oct 13 and Dec 16, 2021, 1290 individuals were screened and 80 were enrolled and randomly assigned to one of the four treatment groups (20 per group). The median age of participants was 13 (IQR 11-20); 37 (46%) of 80 participants were female and 43 (54%) were male. In individuals who were infectious before treatment, the median percentage reduction in mosquito infection rate 2 days after treatment was 100·0% (IQR 100·0-100·0; n=19; p=0·0011) with artemether-lumefantrine and 100·0% (100·0-100·0; n=19; p=0·0001) with artemether-lumefantrine with primaquine. Only two individuals who were infectious at baseline infected mosquitoes on day 2 after artemether-lumefantrine and none at day 5. By contrast, the median percentage reduction in mosquito infection rate 7 days after treatment was 63·6% (IQR 0·0-100·0; n=20; p=0·013) with sulfadoxine-pyrimethamine plus amodiaquine and 100% (100·0-100·0; n=19; p<0·0001) with sulfadoxine-pyrimethamine plus amodiaquine with tafenoquine. No grade 3-4 or serious adverse events occurred. INTERPRETATION: These data support the effectiveness of artemether-lumefantrine alone for preventing nearly all mosquito infections. By contrast, there was considerable post-treatment transmission after sulfadoxine-pyrimethamine plus amodiaquine; therefore, the addition of a transmission-blocking drug might be beneficial in maximising its community impact. FUNDING: Bill & Melinda Gates Foundation.


Asunto(s)
Amodiaquina , Antimaláricos , Combinación Arteméter y Lumefantrina , Combinación de Medicamentos , Fluorenos , Malaria Falciparum , Plasmodium falciparum , Primaquina , Pirimetamina , Sulfadoxina , Humanos , Antimaláricos/uso terapéutico , Antimaláricos/administración & dosificación , Pirimetamina/uso terapéutico , Pirimetamina/administración & dosificación , Amodiaquina/uso terapéutico , Amodiaquina/administración & dosificación , Sulfadoxina/uso terapéutico , Sulfadoxina/administración & dosificación , Masculino , Adulto , Femenino , Adolescente , Niño , Malaria Falciparum/transmisión , Malaria Falciparum/prevención & control , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/epidemiología , Método Simple Ciego , Persona de Mediana Edad , Primaquina/uso terapéutico , Primaquina/administración & dosificación , Combinación Arteméter y Lumefantrina/uso terapéutico , Combinación Arteméter y Lumefantrina/administración & dosificación , Adulto Joven , Fluorenos/administración & dosificación , Fluorenos/uso terapéutico , Malí/epidemiología , Plasmodium falciparum/efectos de los fármacos , Artemisininas/administración & dosificación , Artemisininas/uso terapéutico , Aminoquinolinas/administración & dosificación , Aminoquinolinas/uso terapéutico , Aminoquinolinas/efectos adversos , Etanolaminas/administración & dosificación , Etanolaminas/uso terapéutico , Animales , Quimioterapia Combinada
13.
Daru ; 32(1): 133-144, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38168007

RESUMEN

PURPOSE: Despite the advances in treatment, lung cancer is a global concern and necessitates the development of new treatments. Biguanides like metformin (MET) and artemisinin (ART) have recently been discovered to have anti-cancer properties. As a consequence, in the current study, the anti-cancer effect of MET and ART co-encapsulated in niosomal nanoparticles on lung cancer cells was examined to establish an innovative therapy technique. METHODS: Niosomal nanoparticles (Nio-NPs) were synthesized by thin-film hydration method, and their physicochemical properties were assessed by FTIR. The morphology of Nio-NPs was evaluated with FE-SEM and AFM. The MTT assay was applied to evaluate the cytotoxic effects of free MET, free ART, their encapsulated form with Nio-NPs, as well as their combination, on A549 cells. Apoptosis assay was utilized to detect the biological processes involved with programmed cell death. The arrest of cell cycle in response to drugs was assessed using a cell cycle assay. Following a 48-h drug treatment, the expression level of hTERT, Cyclin D1, BAX, BCL-2, Caspase 3, and 7 genes were assessed using the qRT-PCR method. RESULTS: Both MET and ART reduced the survival rate of lung cancer cells in the dose-dependent manner. The IC50 values of pure ART and MET were 195.2 µM and 14.6 mM, respectively while in nano formulated form their IC50 values decreased to 56.7 µM and 78.3 µM, respectively. The combination of MET and ART synergistically decreased the proliferation of lung cancer cells, compared to the single treatments. Importantly, the combination of MET and ART had a higher anti-proliferative impact against A549 lung cancer cells, with lower IC50 values. According to the result of Real-time PCR, hTERT, Cyclin D1, BAX, BCL-2, Caspase 3, and Caspase 7 genes expression were considerably altered in treated with combination of nano formulated MET and ART compared to single therapies. CONCLUSION: The results of this study showed that the combination of MET and ART encapsulated in Nio-NPs could be useful for the treatment of lung cancer and can increase the efficiency of lung cancer treatment.


Asunto(s)
Apoptosis , Artemisininas , Neoplasias Pulmonares , Metformina , Nanopartículas , Humanos , Artemisininas/farmacología , Artemisininas/química , Artemisininas/administración & dosificación , Metformina/farmacología , Metformina/química , Metformina/administración & dosificación , Neoplasias Pulmonares/tratamiento farmacológico , Células A549 , Apoptosis/efectos de los fármacos , Nanopartículas/química , Níquel/química , Polietilenglicoles/química , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/administración & dosificación , Supervivencia Celular/efectos de los fármacos , Liposomas/química , Proliferación Celular/efectos de los fármacos
14.
Lancet Infect Dis ; 24(5): 476-487, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38224706

RESUMEN

BACKGROUND: The cornerstone of malaria prevention in pregnancy, intermittent preventive treatment (IPTp) with sulfadoxine-pyrimethamine, is contraindicated in women with HIV who are receiving co-trimoxazole prophylaxis. We assessed whether IPTp with dihydroartemisinin-piperaquine is safe and effective in reducing the risk of malaria infection in women with HIV receiving co-trimoxazole prophylaxis and antiretroviral drugs. METHODS: For this randomised, double-blind, placebo-controlled clinical trial, women with HIV attending the first antenatal care clinic visit, resident in the study area, and with a gestational age up to 28 weeks were enrolled at five sites in Gabon and Mozambique. Participants were randomly assigned (1:1) to receive either IPTp with dihydroartemisinin-piperaquine at each scheduled antenatal care visit plus daily co-trimoxazole (intervention group) or placebo at each scheduled antenatal care visit plus daily co-trimoxazole (control group). Randomisation was done centrally via block randomisation (block sizes of eight), stratified by country. IPTp was given over 3 days under direct observation by masked study personnel. The number of daily IPTp tablets was based on bodyweight and according to the treatment guidelines set by WHO (target dose of 4 mg/kg per day [range 2-10 mg/kg per day] of dihydroartemisinin and 18 mg/kg per day [range 16-27 mg/kg per day] of piperaquine given once a day for 3 days). At enrolment, all participants received co-trimoxazole (fixed combination drug containing 800 mg trimethoprim and 160 mg sulfamethoxazole) for daily intake. The primary study outcome was prevalence of peripheral parasitaemia detected by microscopy at delivery. The modified intention-to-treat population included all randomly assigned women who had data for the primary outcome. Secondary outcomes included frequency of adverse events, incidence of clinical malaria during pregnancy, and frequency of poor pregnancy outcomes. All study personnel, investigators, outcome assessors, data analysts, and participants were masked to treatment assignment. This study is registered with ClinicalTrials.gov, NCT03671109. FINDINGS: From Sept 18, 2019, to Nov 26, 2021, 666 women (mean age 28·5 years [SD 6·4]) were enrolled and randomly assigned to the intervention (n=332) and control (n=334) groups. 294 women in the intervention group and 308 women in the control group had peripheral blood samples taken at delivery and were included in the primary analysis. Peripheral parasitaemia at delivery was detected in one (<1%) of 294 women in the intervention group and none of 308 women in the control group. The incidence of clinical malaria during pregnancy was lower in the intervention group than in the control group (one episode in the intervention group vs six in the control group; relative risk [RR] 0·12, 95% CI 0·03-0·52, p=0·045). In a post-hoc analysis, the composite outcome of overall malaria infection (detected by any diagnostic test during pregnancy or delivery) was lower in the intervention group than in the control group (14 [5%] of 311 women vs 31 [10%] of 320 women; RR 0·48, 95% CI 0·27-0·84, p=0·010). The frequency of serious adverse events and poor pregnancy outcomes (such as miscarriages, stillbirths, premature births, and congenital malformations) did not differ between groups. The most frequently reported drug-related adverse events were gastrointestinal disorder (reported in less than 4% of participants) and headache (reported in less than 2% of participants), with no differences between study groups. INTERPRETATION: In the context of low malaria transmission, the addition of IPTp with dihydroartemisinin-piperaquine to co-trimoxazole prophylaxis in pregnant women with HIV did not reduce peripheral parasitaemia at delivery. However, the intervention was safe and associated with a decreased risk of clinical malaria and overall Plasmodium falciparum infection, so it should be considered as a strategy to protect pregnant women with HIV from malaria. FUNDING: European and Developing Countries Clinical Trials Partnership 2 (EDCTP2) and Medicines for Malaria Venture. TRANSLATIONS: For the Portuguese and French translations of the abstract see Supplementary Materials section.


Asunto(s)
Antimaláricos , Artemisininas , Infecciones por VIH , Malaria , Piperazinas , Quinolinas , Combinación Trimetoprim y Sulfametoxazol , Humanos , Femenino , Embarazo , Mozambique/epidemiología , Quinolinas/uso terapéutico , Quinolinas/administración & dosificación , Quinolinas/efectos adversos , Artemisininas/uso terapéutico , Artemisininas/administración & dosificación , Artemisininas/efectos adversos , Antimaláricos/uso terapéutico , Antimaláricos/administración & dosificación , Antimaláricos/efectos adversos , Método Doble Ciego , Adulto , Infecciones por VIH/complicaciones , Gabón/epidemiología , Malaria/prevención & control , Malaria/tratamiento farmacológico , Combinación Trimetoprim y Sulfametoxazol/administración & dosificación , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico , Combinación Trimetoprim y Sulfametoxazol/efectos adversos , Adulto Joven , Complicaciones Parasitarias del Embarazo/prevención & control , Complicaciones Parasitarias del Embarazo/tratamiento farmacológico , Resultado del Tratamiento , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Complicaciones Infecciosas del Embarazo/prevención & control , Combinación de Medicamentos
15.
N Engl J Med ; 389(13): 1191-1202, 2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37754284

RESUMEN

BACKGROUND: Although the clinical efficacy of antimalarial artemisinin-based combination therapies in Africa remains high, the recent emergence of partial resistance to artemisinin in Plasmodium falciparum on the continent is troubling, given the lack of alternative treatments. METHODS: In this study, we used data from drug-efficacy studies conducted between 2016 and 2019 that evaluated 3-day courses of artemisinin-based combination therapy (artesunate-amodiaquine or artemether-lumefantrine) for uncomplicated malaria in Eritrea to estimate the percentage of patients with day-3 positivity (i.e., persistent P. falciparum parasitemia 3 days after the initiation of therapy). We also assayed parasites for mutations in Pfkelch13 as predictive markers of partial resistance to artemisinin and screened for deletions in hrp2 and hrp3 that result in variable performance of histidine rich protein 2 (HRP2)-based rapid diagnostic tests for malaria. RESULTS: We noted an increase in the percentage of patients with day-3 positivity from 0.4% (1 of 273) in 2016 to 1.9% (4 of 209) in 2017 and 4.2% (15 of 359) in 2019. An increase was also noted in the prevalence of the Pfkelch13 R622I mutation, which was detected in 109 of 818 isolates before treatment, from 8.6% (24 of 278) in 2016 to 21.0% (69 of 329) in 2019. The odds of day-3 positivity increased by a factor of 6.2 (95% confidence interval, 2.5 to 15.5) among the patients with Pfkelch13 622I variant parasites. Partial resistance to artemisinin, as defined by the World Health Organization, was observed in Eritrea. More than 5% of the patients younger than 15 years of age with day-3 positivity also had parasites that carried Pfkelch13 R622I. In vitro, the R622I mutation conferred a low level of resistance to artemisinin when edited into NF54 and Dd2 parasite lines. Deletions in both hrp2 and hrp3 were identified in 16.9% of the parasites that carried the Pfkelch13 R622I mutation, which made them potentially undetectable by HRP2-based rapid diagnostic tests. CONCLUSIONS: The emergence and spread of P. falciparum lineages with both Pfkelch13-mediated partial resistance to artemisinin and deletions in hrp2 and hrp3 in Eritrea threaten to compromise regional malaria control and elimination campaigns. (Funded by the Bill and Melinda Gates Foundation and others; Australian New Zealand Clinical Trials Registry numbers, ACTRN12618001223224, ACTRN12618000353291, and ACTRN12619000859189.).


Asunto(s)
Antimaláricos , Combinación Arteméter y Lumefantrina , Resistencia a Medicamentos , Malaria Falciparum , Plasmodium falciparum , Humanos , Amodiaquina/administración & dosificación , Amodiaquina/farmacología , Amodiaquina/uso terapéutico , Antimaláricos/farmacología , Antimaláricos/uso terapéutico , Combinación Arteméter y Lumefantrina/farmacología , Combinación Arteméter y Lumefantrina/uso terapéutico , Artemisininas/administración & dosificación , Artemisininas/farmacología , Artemisininas/uso terapéutico , Resistencia a Medicamentos/genética , Eritrea/epidemiología , Malaria Falciparum/tratamiento farmacológico , Malaria Falciparum/epidemiología , Malaria Falciparum/genética , Malaria Falciparum/parasitología , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/genética , Prevalencia
16.
Parasit Vectors ; 15(1): 435, 2022 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-36397132

RESUMEN

BACKGROUND: Vector control interventions in sub-Saharan Africa rely on insecticide-treated nets and indoor residual spraying. Insecticide resistance, poor coverage of interventions, poor quality nets and changes in vector behavior threaten the effectiveness of these interventions and, consequently, alternative tools are needed. Mosquitoes die after feeding on humans or animals treated with ivermectin (IVM). Mass drug administration (MDA) with IVM could reduce vector survival and decrease malaria transmission. The entomological impact of MDA of combined IVM and dihydroartemisinin-piperaquine was assessed in a community-based, cluster-randomized trial. METHODS: A cluster-randomized trial was implemented in 2018 and 2019 in 32 villages in the Upper River Region, The Gambia. The with the inhabitants of 16 intervention villages eligible to receive three monthly rounds of MDA at the beginning of the malaria transmission season. Entomological surveillance with light traps and human landing catches (HLC) was carried out during a 7- to 14-day period after each round of MDA, and then monthly until the end of the year. The mosquitocidal effect of IVM was determined by direct membrane feeding assays. RESULTS: Of the 15,017 mosquitoes collected during the study period, 99.65% (n = 14,965) were Anopheles gambiae sensu lato (An. gambiae s.l.), comprising Anopheles arabiensis (56.2%), Anopheles coluzzii (24.5%), Anopheles gambiae sensu stricto (An. gembiae s.s.; 16.0%) and Anopheles funestus sensu lato (An. funestus s.l.; 0.35%). No effect of the intervention on vector parity was observed. Vector density determined on light trap collections was significantly lower in the intervention villages in 2019 (adjusted incidence rate ratio: 0.39; 95% confidence interval [CI]: 0.20, 0.74; P = 0.005) but not in 2018. However, vector density determined in HLC collections was similar in both the intervention and control villages. The entomological inoculation rate was significantly lower in the intervention villages than in the control villages (odds ratio: 0.36, 95% CI: 0.19, 0.70; P = 0·003). Mosquito mortality was significantly higher when blood fed on IVM-treated individuals up to 21 days post-treatment, particularly in adults and individuals with a higher body mass index. CONCLUSION: Mass drug administration with IVM decreased vector density and the entomological inoculation rate while the effect on vector parity was less clear. Survival of mosquitoes fed on blood collected from IVM-treated individuals was significantly lower than that in mosquitoes which fed on controls. The influence of host characteristics on mosquito survivorship indicated that dose optimization could improve IVM efficacy. Future detailed entomological evaluation trials in which IVM is administered as stand-alone intervention may elucidate the contribution of this drug to the observed reduction in transmission.


Asunto(s)
Anopheles , Artemisininas , Ivermectina , Malaria , Administración Masiva de Medicamentos , Adulto , Animales , Humanos , Anopheles/efectos de los fármacos , Artemisininas/administración & dosificación , Artemisininas/uso terapéutico , Gambia/epidemiología , Ivermectina/administración & dosificación , Ivermectina/uso terapéutico , Malaria/prevención & control , Mosquitos Vectores/efectos de los fármacos
17.
Regul Toxicol Pharmacol ; 129: 105114, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35007669

RESUMEN

Artemisinin-hydroxychloroquine sulfate tablets (AH) are considered a relatively inexpensive and novel combination therapy for treating all forms of malaria, especially aminoquinoline drugs-resistant strains of P.falciparum. We aim to carry out acute and subacute oral toxicity studies in rats to acquire preclinical data on the safety of AH. Acute toxicity was evaluated in Sprague-Dawley (SD) rats at a single dose of 1980, 2970, 4450, 6670, and 10000 mg/kg. A 14-days subacute toxicity was assessed in SD rats at doses of 0, 146, 219, 328, and 429 mg/kg. The median lethal dose (LD50) of acute oral administration of AH in rats is found to be 3119 mg/kg, and toxic symptoms include decreased spontaneous activity, dyspnea, bristling, soft feces, spasticity, and convulsion. Repeated doses of AH have toxic effects on the nervous system, skin, blood system, liver, kidney, and spleen in rats. The main toxic reactions include epilation, emaciation, mental irritability, decreased body weight gain and food consumption, changes in the hematological and biochemical parameters, especially pathological lesions in the liver, kidney, and spleen. The no-observed-adverse-effect level (NOAEL) and lowest-observed-adverse-effect level (LOAEL) of AH are considered to be 219 mg/kg and 328 mg/kg, respectively.


Asunto(s)
Antimaláricos/toxicidad , Artemisininas/toxicidad , Hidroxicloroquina/toxicidad , Administración Oral , Animales , Antimaláricos/administración & dosificación , Antimaláricos/farmacología , Artemisininas/administración & dosificación , Artemisininas/farmacología , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Femenino , Hidroxicloroquina/administración & dosificación , Hidroxicloroquina/farmacología , Dosificación Letal Mediana , Masculino , Nivel sin Efectos Adversos Observados , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Pruebas de Toxicidad Aguda , Pruebas de Toxicidad Subaguda
18.
Lancet Infect Dis ; 22(4): 519-528, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34919831

RESUMEN

BACKGROUND: Although the malaria burden has substantially decreased in sub-Saharan Africa, progress has stalled. We assessed whether mass administration of ivermectin (a mosquitocidal drug) and dihydroartemisinin-piperaquine (an antimalarial treatment) reduces malaria in The Gambia, an area with high coverage of standard control interventions. METHODS: This open-label, cluster-randomised controlled trial was done in the Upper River region of eastern Gambia. Villages with a baseline Plasmodium falciparum prevalence of 7-46% (all ages) and separated from each other by at least 3 km to reduce vector spillover were selected. Inclusion criteria were age and anthropometry (for ivermectin, weight of ≥15 kg; for dihydroartemisinin-piperaquine, participants older than 6 months); willingness to comply with trial procedures; and written informed consent. Villages were randomised (1:1) to either the intervention (ivermectin [orally at 300-400 µg/kg per day for 3 consecutive days] and dihydroartemisinin-piperaquine [orally depending on bodyweight] plus standard control interventions) or the control group (standard control interventions) using computer-based randomisation. Laboratory staff were masked to the origin of samples. In the intervention group, three rounds of mass drug administration once per month with ivermectin and dihydroartemisinin-piperaquine were given during two malaria transmission seasons from Aug 27 to Oct 31, 2018, and from July 15 to Sept 30, 2019. Primary outcomes were malaria prevalence by qPCR at the end of the second intervention year in November 2019, and Anopheles gambiae (s l) parous rate, analysed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT03576313. FINDINGS: Between Nov 20 and Dec 7, 2017, 47 villages were screened for eligibility in the study. 15 were excluded because the baseline malaria prevalence was less than 7% (figure 1). 32 villages were enrolled and randomised to either the intervention or control group (n=16 in each group). The study population was 10 638, of which 4939 (46%) participants were in intervention villages. Coverage for dihydroartemisinin-piperaquine was between 49·0% and 58·4% in 2018, and between 76·1% and 86·0% in 2019; for ivermectin, coverage was between 46·9% and 52·2% in 2018, and between 71·7% and 82·9% in 2019. In November 2019, malaria prevalence was 12·8% (324 of 2529) in the control group and 5·1% (140 of 2722) in the intervention group (odds ratio [OR] 0·30, 95% CI 0·16-0·59; p<0·001). A gambiae (s l) parous rate was 83·1% (552 of 664) in the control group and 81·7% (441 of 540) in the intervention group (0·90, 0·66-1·25; p=0·537). In 2019, adverse events were recorded in 386 (9·7%) of 3991 participants in round one, 201 (5·4%) of 3750 in round two, and 168 (4·5%) of 3752 in round three. None of the 11 serious adverse events were related to the intervention. INTERPRETATION: The intervention was safe and well tolerated. In an area with high coverage of standard control interventions, mass drug administration of ivermectin and dihydroartemisinin-piperaquine significantly reduced malaria prevalence; however, no effect of ivermectin on vector parous rate was observed. FUNDING: Joint Global Health Trials Scheme. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.


Asunto(s)
Antimaláricos , Artemisininas , Malaria , Quinolinas , Animales , Antimaláricos/administración & dosificación , Artemisininas/administración & dosificación , Gambia/epidemiología , Humanos , Ivermectina/administración & dosificación , Malaria/prevención & control , Administración Masiva de Medicamentos , Mosquitos Vectores , Piperazinas , Quinolinas/administración & dosificación
19.
Small Methods ; 5(12): e2101047, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34928038

RESUMEN

Cisplatin has been used as standard regimen for hepatocellular carcinoma (HCC), but its therapeutic efficacy is greatly limited by the drug resistance. Cisplatin alone cannot achieve an ideal therapeutic outcome. Herein, a dual threat hybrid artemisinin platinum (ArtePt) is synthesized to combine chemodynamic therapy (CDT) with chemotherapy. On the one hand, artesunate can react with intracellular ferrous ion to generate reactive oxygen species (ROS) via Fenton reaction for CDT. On the other hand, cisplatin can target DNA for chemotherapy. However, GSH in cancer cells can effectively consume free radicals and detoxify cisplatin simultaneously, which compromised the efficacy of CDT and chemotherapy. Hence, an amphiphilic polymer with an iodine atom in the side chain is designed and encapsulated ArtePt to form NP(ArtePt). This iodine containing polymer NP(ArtePt) can effectively deplete intracellular GSH via an Iodo-Click reaction, thereby enhancing the effect of CDT as well as chemotherapy. Thereafter, a patient-derived xenograft model of hepatic carcinoma (PDXHCC ) is established to evaluate the therapeutic effect of NP(ArtePt), and a significant antitumor effect is achieved with NP(ArtePt). Overall, this study provides an effective strategy to combine CDT with chemotherapy to enhance the efficacy of cisplatin via Iodo-Click reaction, opening a new avenue for the cancer treatment.


Asunto(s)
Artemisininas/administración & dosificación , Carcinoma Hepatocelular/tratamiento farmacológico , Cisplatino/administración & dosificación , Glutatión/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Animales , Artemisininas/química , Artemisininas/farmacología , Carcinoma Hepatocelular/metabolismo , Cisplatino/química , Cisplatino/farmacología , Química Clic , Humanos , Neoplasias Hepáticas/metabolismo , Ratones , Microscopía Confocal , Nanopartículas , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Resultado del Tratamiento
20.
Nat Commun ; 12(1): 6714, 2021 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-34795281

RESUMEN

Intermittent preventive treatment (IPT) with dihydroartemisinin-piperaquine (DP) is highly protective against malaria in children, but is not standard in malaria-endemic countries. Optimal DP dosing regimens will maximize efficacy and reduce toxicity and resistance selection. We analyze piperaquine (PPQ) concentrations (n = 4573), malaria incidence data (n = 326), and P. falciparum drug resistance markers from a trial of children randomized to IPT with DP every 12 weeks (n = 184) or every 4 weeks (n = 96) from 2 to 24 months of age (NCT02163447). We use nonlinear mixed effects modeling to establish malaria protective PPQ levels and risk factors for suboptimal protection. Compared to DP every 12 weeks, DP every 4 weeks is associated with 95% protective efficacy (95% CI: 84-99%). A PPQ level of 15.4 ng/mL reduces the malaria hazard by 95%. Malnutrition reduces PPQ exposure. In simulations, we show that DP every 4 weeks is optimal across a range of transmission intensities, and age-based dosing improves malaria protection in young or malnourished children.


Asunto(s)
Artemisininas/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Plasmodium falciparum/efectos de los fármacos , Complicaciones Parasitarias del Embarazo/tratamiento farmacológico , Quinolinas/uso terapéutico , Algoritmos , Antimaláricos/administración & dosificación , Antimaláricos/farmacocinética , Antimaláricos/uso terapéutico , Artemisininas/administración & dosificación , Artemisininas/farmacocinética , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Incidencia , Lactante , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Masculino , Modelos Biológicos , Evaluación de Resultado en la Atención de Salud/métodos , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Plasmodium falciparum/fisiología , Embarazo , Complicaciones Parasitarias del Embarazo/metabolismo , Quinolinas/administración & dosificación , Quinolinas/farmacocinética , Uganda/epidemiología
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