Artesunate Combined with Other Medications and Action Mechanism： A Review / 中国实验方剂学杂志

A sesquiterpene natural substance called artemisinin was discovered in Artemisia annua. One of its derivatives， artesunate （ART）， has the properties of economy， immediate effect， low toxicity， and good tolerance. Since it has a quick and powerful killing effect on plasmodium in the erythrocyte phase and can quickly handle clinical seizure and symptoms， it is currently mostly utilized to treat cerebral malaria and other severe instances of malaria. In addition， it has antitumor， antivirus， anti-hepatic fibrosis， anti-inflammatory， antibacterial， hepatocyte protection， immunological modulation， and other pharmacological properties and can inhibit cell proliferation， induce cell apoptosis， and reduce the incidence of sepsis. In many countries， artemisinin-based combination therapies （ACTs）， such as artemether-benflumetol， artesunate-amodiaquine， and artemether-lumefantrine， are the first-line treatments for malaria. Recent research on artesunate by Chinese and international scholars has revealed that compared with monotherapy， artesunate combination therapy offers more benefits in terms of improving pharmacological effects， shortening the duration of medicine， and minimizing adverse effects. Through systematic retrieval of Web of Science Core Collection and integration through CiteSpace （6.2.1） software， this article reviewed the mechanism of artesunate combined with other medications with regard to antimalarial， antitumor， antibacterial， and antiviral features in the previous five years， so as to provide some theoretical basis for rational development and utilization of ART and new drug research and development.

Progress of researches on antimalarial peptides / 中国血吸虫病防治杂志

Malaria remains a major global public health concern, and nearly half of the global populations are still at risk of malaria infection. However, continuous emergence and spread of drug-resistant malaria parasite strains lead to ineffectiveness of conventional antimalarials. Therefore, development of novel antimalarial agents is of urgent need for malaria elimination. As an important component of the host natural immune defense system, antibacterial peptides provide the first line of defense against pathogenic invasion, and the mechanism of preferentially attacking the cell membrane makes them difficult to develop drug resistance. Antimicrobial peptides are therefore considered as a promising candidate for novel antimalarial agents. This review summarizes the advances in researches on antimicrobial peptides with antimalarial actions and discusses the potential of antimalarial peptides as novel antimalarials.

The stereoselective synthesis of privileged epimer of C-10 carba artemisinins and the effect of substituted groups with different acid-base properties on the antimalarial activity / 药学学报

Artemisinin is a sesquiterpene lactone natural product that contains an endoperoxide bond. Artemisinin has various biological activities including antimalarial, anti-tumor, antiviral and anti-fibrotic activity. Owing to the poor pharmacokinetic properties of artemisinin, its derivatives are currently used in clinic and frequently reported in literature. Although numerous derivatives of artemisinin have been reported, no study has been carried out yet to study the effect of substituted groups with different acid-base property on the antimalarial activity. Among these derivatives, the C-10 carbon artemisinin derivatives are often reported, and their corresponding 10β epimer show much better antimalarial activity than 10α epimer with large-sized substitute. However, there is currently no stereoselective synthesis to efficiently prepare the privileged 10β epimer of C-10 carba artemisinin. To address these two scientific questions, we herein first report an optimized method to stereoselectively synthesize the 10β epimer of C-10 carba artemisinin (98∶2 d.r.). Second, we employed the optimized method to synthesize a series of C-10 carba artemisinin derivatives with different acid-base properties. The antimalarial examination indicated that those derivatives with neutral groups or basic group of short chain showed similar antimalarial activity as dihydroartemisinin (DHA). The acidic group could dramatically decrease the antimalarial effect and was more than 22-fold less effective than DHA or the neutral ones. This study will shed light on the development of new generation of artemisinin derivatives with potent activity.

Exposing the Hepatotoxicity of Medicinal Plants: A Review of Copalchi Stem Bark (Hintonia latiflora) / Exponiendo la hepatotoxicidad de las plantas medicinales: una revisión de palo amargo (Hintonia latiflora)

Resumen Se estima que el 80% de la población mundial utiliza diversas plantas medicinales para el tratamiento o control de diversas enfermedades, ya sean agudas o crónicas, debido a su accesibilidad y bajo costo, observándose en los últimos años un aumento en el consumo sin una observación médica adecuada. México es considerado como el segundo país más importante del mundo en cuanto al conocimiento de la medicina tradicional, solo después de china. El uso de las plantas medicinales se ha reportado desde tiempos prehispánicos como una opción terapéutica, sin embargo, el único enfoque que se tiene es la parte curativa y no se ha reflexionado en que las plantas poseen metabolitos secundarios (compuestos químicos producidos por las plantas con actividad biológica en los seres vivos) que, además de tener efectos terapéuticos poseen efectos tóxicos en las personas que las consumen, observándose en algunos casos efectos reversibles después de suspender su consumo. El copalchi o palo amargo es una planta medicinal que proviene de la corteza del árbol de Hintonia latiflora (sin. Coutarea latiflora), la cual ha sido utilizada principalmente como tratamiento alternativo para pacientes con diabetes tipo 2, ya que se ha demostrado que tiene efecto hipoglucemiante. Sin embargo, se han reportado casos de hepatotoxicidad aguda con un incremento en las transaminasas hepáticas (ALT y AST) por el consumo continuo de dicha corteza, no obstante el procesamiento de las plantas medicinales utilizando medios físicos (calentar o hervir) puede alterar la actividad farmacológica de los constituyentes orgánicos, los cuales pueden verse también afectados en su concentración dependiendo de los factores ambientales de cultivo, localización del suelo, humedad y temperatura ambiental, así como la temporada de cosecha (tallos, hojas, flores, raíces, semillas). El consumo de esta planta medicinal es por medio de infusiones calientes o en cápsulas con extracto.

Abstract Approximately 80% of the world's population uses various medicinal plants for the treatment or control of various diseases, whether acute or chronic, due to their accessibility and low cost, observing in recent years an increase in consumption without proper medical observation. Mexico is considered the second most important country in the world in terms of traditional medicine knowledge, only after China. The use of medicinal plants has been reported since pre-Hispanic times as a therapeutic option; however, the only focus is on the curative part and it has not been considered that plants have secondary metabolites (chemical compounds produced by plants with biological activity in living beings) that, besides having therapeutic effects, have toxic effects in people who consume them, and in some cases reversible effects are observed after suspending their consumption. Copalchi or palo amargo is a medicinal plant obtained from the bark of the Hintonia latiflora tree (syn. Coutarea latiflora), which has been used mainly as an alternative treatment for patients with type 2 diabetes, since it has been shown to have a hypoglycemic effect. However, cases of acute hepatotoxicity have been reported with an increase in hepatic transaminases (ALT and AST) by the continuous consumption of this bark. However, the processing of medicinal plants using physical means (heating or boiling) can alter the pharmacological activity of the organic constituents, which can also be affected in their concentration depending on the environmental factors of cultivation, soil location, humidity, and environmental temperature, as well as the harvesting season (stems, leaves, flowers, roots, seeds). The consumption of this medicinal plant is by means of hot infusions or in capsules with extract.

In vivo Chemosuppressive effects of Combinations of Three Nigerian Ethnomedicinal Antimalarial Plants

Aims: Appropriate ratios for combining some African ethnomedicinal plants with proven anti-plasmodial activity were determined with the aim of obtaining herbal remedies with higher efficacies. Place and Duration of the Study: Study was conducted in the Department of Pharmacognosy, Obafemi Awolowo University, Ile-Ife Nigeria. Study Design: Infusions of dried powders of three Nigerian ethnomedicinal plants, Eugenia uniflora leaf, Gongronema latifolium root and stem and Artocarpus altilis stem bark, were separately evaluated and in varied combination ratios for their anti-plasmodial activities Methodology: The infusions were separately prepared, concentrated in vacuo, freeze-dried and evaluated at 400mg/kg against Plasmodium berghei berghei parasites, using the Peter’s four-day chemosuppressive mice model. Normal saline and chloroquine (10mg/kg) were negative and positive controls, respectively. 2- and 3-combinations of the infusions were similarly tested. Results: Of the 2-plant combination ratios, 1:1, 1:3, 2:3 of EG and GA elicited percentage chemo suppressions which were comparable (P=.28; P=.07) to those of the single drugs. Only the EG ratios gave activities that were comparable (P=.28) to the positive control in addition to double survival times and high survivor values by EG 2:3 and GA 1:3. However, those of the EA group, gave relatively low values, barely above 20% with only the ratios 2:3 and 3:2 giving values which were significantly (P=.00) higher than negative control with double survival times. The 3-plant combination ratios, EGA 2:1:2 and 3:3:2 gave suppressions that were significantly (P=.00) higher than the negative control with others but comparable (P=.33) activities to those of the individual drugs. The other ratios with low suppression values were relatively inactive. But three ratios, EGA 3:1:2, 2:1:1, 1:1:1 elicited survival times doubled (204, 242 and 202 %) that of the negative control without commensurate high antiplasmodial activities. Conclusion: Ethnomedicinal antimalarial plants should not be combined without a data of previous scientific evaluations.

Quantitative standardization of pharmacologically active components from antiplasmodial plant Solanum nudum Dunal (wild and in vitro) / Estandarización cuantitativa de componentes farmacológicamente activos de la planta antiplasmodial Solanum nudum Dunal (silvestre e in vitro)

Solanum nudum Dunal (Solanaceae) is most commonly known andused by the population of the colombian Pacific coast as an antimalarial treatment. This article study into optimization and quantitative analysis of compounds steroidal over time of development of this species when grown in vitro and wild. A new steroidal compound named SN6 was elucidated by NMR and a new method of quantification of seven steroidal compounds (Diosgenone DONA and six steroids SNs) using HPLC-DAD-MS in extracts of cultures in vitroand wild was investigated. Biology activity of extracts was found to a range of antiplasmodial activity in FCB2 and NF-54 with inhibitory concentration (IC50) between (17.04 -100µg/mL) and cytotoxicity in U-937 of CC50 (7.18 -104.7µg/mL). This method creates the basis for the detection of seven sterols antiplasmodial present in extracts from S. nudum plant as a quality parameter in the control and expression of phytochemicals.

Solanum nudum Dunal (Solanaceae) es el más conocido y utilizado por la población de la costa del Pacífico colombiano como tratamiento antipalúdico. Este artículo estudia la optimización y el análisis cuantitativo de compuestos esteroides a lo largo del tiempo de desarrollo de esta especie cuando se cultiva in vitro y en forma silvestre. Un nuevo compuesto esteroideo llamado SN6 fue dilucidado por RMN y se investigó un nuevo método de cuantificación de siete compuestos esteroides (Diosgenone DONA y seis esteroides SN) usando HPLC-DAD-MS en extractos de cultivos in vitro y silvestres. La actividad biológica de los extractos se encontró en un rango de actividad antiplasmodial en FCB2 y NF-54 con concentración inhibitoria (IC50) entre (17.04 -100 µg/mL) y citotoxicidad en U-937 de CC50 (7.18 -104.7 µg/mL). Este método crea la base para la detección de siete esteroles antiplasmodiales presentes en extractos de planta de S. nudum como parámetro de calidad en el control y expresión de fitoquímicos.

Medicinal plants with antimalarial activities mediated via glycogen synthase kinase-3 beta (GSK3β) inhibition

@#Many of the therapeutic effects of plant extracts and bioactive compounds appear related to their immunomodulatory effects and impact on the host immune system. The immune response is desirable to mitigate established infections and, in the case of severe malaria, is a feasible approach to dealing with the overwhelming cytokine response. Glycogen synthase kinase-3 (GSK3), a Ser/Thr kinase that is a central regulator of the cytokine response, is a promising antimalarial drug target. In this review, we discussed our ongoing research projects, which include assessing the antimalarial activities of medicinal plants and their bioactive compounds, immunomodulatory activities mediated by GSK3, and the potential inflammatory pathway involved in malarial infection.

Sustainable development roadmap of Chinese antimalarial products / 中国血吸虫病防治杂志

As the first country that has been certified malaria-free in the WHO Western Pacific Region for more than 3 decades, China should share its successful experiences of malaria control and provide globally recognized anti-malaria products by making full uses of its advantages in provision and production capacity of artemisinin raw materials, to fill the gaps of international demands for mosquito nets, rapid diagnostic reagents and antimalarial compounds. Increasing the investment of research and development of antimalarial products, building overseas bases for artemisinin raw material production, establishing international regulatory authority and promoting the local production of antimalarial products are needed to further promote the internationalization of Chinese antimalarial products, so as to achieve the equity and accessibility of Chinese antimalarial products in highburden regions for malaria.

The current use of the artemisinin-based combination therapies in adult patients at a tertiary hospital, South-South Nigeria

Objective:The antimalarial preferences, tolerability, and cost of the Artemisinin-based combination therapies (ACTs) among adult patients and caregivers are largely understudied despite being the recommendedtreatment for Plasmodium falciparum.We, therefore, evaluated antimalarial preferences, tolerability, and cost of the ACTs among adult patients attending the University of Benin Teaching Hospital, Nigeria. Methods:This was a cross-sectional study conducted among adult patients and their caregivers atthe University of Benin Teaching Hospital, Nigeria,using a semi-structured questionnaire. Their preferred antimalarial medication, previous use of antimalarial monotherapies, current ACT use; cost considerations, and adverse effects profile were sought.Result:Six hundred respondents were recruited with a mean age of 41.4±16.3years and M/F ratio of 1.4. The majority (88.0%), reported that they had between 1-5 episodes of malaria fever in a year. Only 28.2% received doctors' prescriptions while 85.8% purchased their antimalarial medications from a pharmacy. Sixty percent of the respondents used at least one ACT; mainly Artemether-Lumefantrine (AL) 312(52.0%). Only 9.3% reported previous adverse effects with the ACTs with 4.0% of respondents discontinuing their medications. The mean (SD) cost of purchasing ACTs was 1,516.47±760.3 (3.65 USD) Naira.Conclusion: This study showed adult patients' preference for the ACTs, especially Artemether-Lumefantrine despite some inclination towards antimalarial monotherapies and parenteral route. There was also a high rate of use of malaria presumptive treatment, but only a few reported adverse effects. There is a need to make ACTs affordable because the cost is still presently high for most Nigerians.

In vivo antimalarial activity of self-nanoemulsifying drug delivery systems containing ethanolic extract of Morinda lucida in combination with other Congolese plants extracts

Abstract Morinda lucida leaves are largely used by Congolese traditional healers for the treatment of uncomplicated malaria. The antimalarial activity of their ethanolic extract has been confirmed both in vitro and in vivo. However, the development of relevant formulations for potential clinical application is hampered since the active ingredients contained in this extract exhibit poor water solubility and low oral bioavailability. Hence, this work aims not only to develop self-nanoemulsifying drug delivery systems (SNEDDSs) for oral delivery of the ethanolic extract of Morinda lucida (ML) but also to evaluate its oral antimalarial activity alone and in combination with other Congolese ethanolic plant extracts (Alstonia congensis, Garcinia kola, Lantana camara, Morinda morindoides or Newbouldia laevis). Based on the solubility of these different extracts in various excipients, SNEDDS preconcentrates were prepared, and 200 mg/g of each plant extract were suspended in these formulations. The 4-day suppressive Peter's test revealed a significant parasite growth inhibiting effect for all the extract-based SNEDDS (from 55.0 to 82.4 %) at 200 mg/kg. These activities were higher than those of their corresponding ethanolic suspensions given orally at the same dose (p<0.05). The combination therapy of MLSNEDDS with other extract-based SNEDDS exhibited remarkable chemosuppression, ranging from 74.3 % to 95.8 % (for 100 + 100 mg/kg) and 86.7 % to 95.5 % (for 200 + 200 mg/kg/day). In regard to these findings, SNEDDS suspension may constitute a promising approach for oral delivery of ML alone or in combination with other antimalarial plants.

In vitro and in silico assessment of new beta amino ketones with antiplasmodial activity

ABSTRACT Background: Based on the current need for new drugs against malaria, our study evaluated eight beta amino ketones in silico and in vitro for potential antimalarial activity. Methods: Using the Brazilian Malaria Molecular Targets (BraMMT) and OCTOPUS® software programs, the pattern of interactions of beta-amino ketones was described against different proteins of P. falciparum and screened to evaluate their physicochemical properties. The in vitro antiplasmodial activities of the compounds were evaluated using a SYBR Green-based assay. In parallel, in vitro cytotoxic data were obtained using the MTT assay. Results: Among the eight compounds, compound 1 was the most active and selective against P. falciparum (IC50 = 0.98 µM; SI > 60). Six targets were identified in BraMMT that interact with compounds exhibiting a stronger binding energy than the crystallographic ligand: P. falciparum triophosphate phosphoglycolate complex (1LYX), P. falciparum reductase (2OK8), PfPK7 (2PML), P. falciparum glutaredoxin (4N0Z), PfATP6, and PfHT. Conclusions: The physicochemical properties of compound 1 were compatible with the set of criteria established by the Lipinski rule and demonstrated its potential as a drug prototype for antiplasmodial activity.

In vitro assessment for cytotoxicity screening of new antimalarial candidates

Abstract In antimalarial research there are no standard procedures to determine the toxicity of a drug candidate. Among the alternatives available, in vitro cytotoxicity assays are the most widely used to predict toxic effects of future therapeutic products. They have the advantage over the in vivo assays, in that they offer the possibility to restrain the number of experimental variables. The objective of the present study was to compare in vitro cytotoxic methods by testing various compounds currently used to treat malaria against different cell lines. Neutral red (NR) uptake and methylthiazoletetrazolium (MTT) colorimetric in vitro assays were used to determine preliminary toxicity of commercially available antimalarial drugs against tumor and non-tumor cells lines. Toxicity through brine shrimp lethality bioassay and hemolytic activity were also evaluated. Significant differences were observed in the tests measured by NR uptake. The tumor cell lines TOV-21G and HepG2 and non-tumor WI-26VA4 cells showed relatively uniform toxicity results, with TOV-21G being the most sensitive cell tested, presenting the lowest concentration to cause death to 50% of viable cells (CC50) values. The results of this study support the use of TOV-21G, HepG2 and WI-26VA4 cells lines as the choice for cytotoxicity tests to evaluate potential bioactive compounds.

Accelerated atherosclerosis and cardiovascular disease in systemic lupus erythematosus / Aterosclerosis acelerada y enfermedad cardiovascular en el lupus eritematoso sistémico

ABSTRACT Cardiovascular disease (CVD), particularly coronary heart disease and stroke, is one of the most important causes of morbidity and mortality in patients with systemic lupus erythematosus (SLE). The increased prevalence of CVD and subclinical atherosclerosis, even after adjustment for traditional risk factors, are well established. Several associations with disease-related clinical, genetic and immunological features have been identified. The SLE-specific stratification algorithms with emphasis on composite risk-assessment scores including both traditional risk factors and novel biomarkers is recommended. The clinical complexity of accelerated atherosclerosis will most likely require an integrated approach for the identification, treatment, and intensive study into this aspect of SLE that will ultimately lead to improved cardiovascular outcomes for these patients.

RESUMEN La enfermedad cardiovascular (ECV), en particular la enfermedad coronaria y el ictus, es una de las causas más importantes de morbimortalidad en pacientes con lupus eritematoso sistémico (LES). El aumento en la prevalencia de la ECV y de la aterosclerosis subclínica, aun después del ajuste de los factores de riesgo tradicionales, está claramente establecida. Se han identificado diversas asociaciones con características clínicas, genéticas e inmunológicas relacionadas con la enfermedad. Se recomienda el uso de los algoritmos de estratificación específicos para el LES, con énfasis en los puntajes compuestos de evaluación de riesgo, incluyendo tanto los factores de riesgo tradicionales como los nuevos biomarcadores. La complejidad clínica de la aterosclerosis acelerada muy probablemente requerirá un abordaje integral para la identificación, el tratamiento y el estudio intensivo de este aspecto del LES, que en última instancia permita obtener mejores desenlaces cardiovasculares en estos pacientes.

Desarrollo y validación interna de un modelo de predicción clínica del riesgo de infección bacteriana nosocomial en pacientes con lupus eritematoso sistémico / Development and internal validation of a clinical prediction model of the risk of nosocomial bacterial infection in patients with systemic lupus erythematosus

RESUMEN Introducción: Los pacientes con lupus eritematoso sistémico (LES) tienen un riesgo aumen tado de padecer infecciones tanto adquiridas en la comunidad como asociadas con el cuidado de la salud. Las infecciones bacterianas son las más frecuentes y graves durante la hospitalización de estos pacientes. Objetivo: Desarrollar y validar internamente un modelo de predicción clínica de pronóstico del riesgo de infección bacteriana adquirida en el hospital en pacientes con LES, usando datos clínicos y de laboratorio obtenidos durante las primeras horas de hospitalización. Métodos: Se analizó una cohorte retrospectiva de pacientes con LES mayores de 16 arios, hos pitalizados por motivos diferentes a infección bacteriana en 2 hospitales de alta complejidad de Medellín entre 2011 y 2016. Se compararon las características de los pacientes que des arrollaron el desenlace de infección bacteriana entre el día 3 y el día 15 de hospitalización con aquellos que no lo presentaron. Las variables significativas en el análisis bivariado fueron consideradas para la construcción del modelo por medio de regresión logística multivariada. Resultados: Se incluyeron 765 episodios, de los cuales 98 (12,8%) presentaron el desenlace de interés. Se consideraron 35 predictores candidatos. Las variables incorporadas en el modelo final fueron: edad, recuento de neutrófilos, puntaje de actividad lúpica SLEDAI, uso de sonda vesical, uso de catéter venoso central en las primeras 72 h, dosis de glucocorticoides en el mes previo y el uso de un antimalárico en los 3 meses previos. La capacidad de discrimi nación del modelo fue aceptable a buena (AUC-ROC 0,74; IC 95% 0,69-0,80). La prueba de bondad de ajuste de Hosmer-Lemeshow (p = 0,637) evidenció una adecuada calibración. Conclusión: Desarrollamos un modelo de predicción clínica de pronóstico del riesgo de infec ción bacteriana nosocomial en pacientes con LES. El modelo desarrollado está compuesto por variables clínicas y de laboratorio simples disponibles en el momento del ingreso al hospital. Se requieren estudios de validación externa y de impacto clínico antes de su implementación rutinaria.

ABSTRACT Introduction: Patients with systemic lupus erythematosus (SLE) have an increased risk of developing community-acquired infections, as well as those associated with health care. Bacterial infections are the most common and serious while these patients are in hospital. Objective: To develop, and internally validate, a clinical prediction model for the prognosis of the risk of hospital-acquired bacterial infection in SLE patients using clinical and laboratory data obtained during the first hours of hospital admission. Methods: An analysis was performed on retrospective cohort of patients with SLE older than 16 years and admitted for reasons other than bacterial infection in 2 highly complex hospitals in Medellín between 2011 and 2016. The characteristics of the patients who developed a bacterial infection were compared between day 3 and day 15 of hospital admission with those who did not develop one. The significant variables in the bivariate analysis were used for the construction of the model using multivariate logistic regression. Results: A total of 765 episodes were included, of which 98 (12.8%) presented the outcome of interest. Thirty-five candidate predictors were considered. The variables incorporated in the final model were: age, neutrophil count, SLEDAI lupus activity score, use of a bladder catheter, use of a central venous catheter in the first 72 h, glucocorticoid doses in the previous month, and use of an antimalarial drug in the 3 previous months. The discrimination capacity of the model was acceptable to good (AUC-ROC 0.74; 95% CI 0.69-0.80). The Hosmer-Lemeshow goodness of fit test (P = .637) suggested adequate calibration. Conclusion: A clinical prediction model of prognostic risk of nosocomial bacterial infection in patients with SLE has been developed. This model is made up of simple clinical and laboratory variables available at the time of hospital admission. External validation and clinical impact studies are required before routine implementation.

Design, synthesis, and biological evaluation of multiple targeting antimalarials

Malaria still threatens global health seriously today. While the current discoveries of antimalarials are almost totally focused on single mode-of-action inhibitors, multi-targeting inhibitors are highly desired to overcome the increasingly serious drug resistance. Here, we performed a structure-based drug design on mitochondrial respiratory chain of

Dehydrobufotenin extracted from the Amazonian toad Rhinella marina (Anura: Bufonidae) as a prototype molecule for the development of antiplasmodial drugs

he resistance against antimalarial drugs represents a global challenge in the fight and control of malaria. The Brazilian biodiversity can be an important tool for research and development of new medicinal products. In this context, toxinology is a multidisciplinary approach on the development of new drugs, including the isolation, purification, and evaluation of the pharmacological activities of natural toxins. The present study aimed to evaluate the cytotoxicity, as well as the antimalarial activity in silico and in vitro of four compounds isolated from Rhinella marina venom as potential oral drug prototypes. Methods: Four compounds were challenged against 35 target proteins from P. falciparum and screened to evaluate their physicochemical properties using docking assay in Brazilian Malaria Molecular Targets (BraMMT) software and in silico assay in OCTOPUS® software. The in vitro antimalarial activity of the compounds against the 3D7 Plasmodium falciparum clones were assessed using the SYBR Green I based assay (IC50). For the cytotoxic tests, the LD50 was determined in human pulmonary fibroblast cell line using the [3(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay. Results: All compounds presented a ligand-receptor interaction with ten Plasmodium falciparum-related protein targets, as well as antimalarial activity against chloroquine resistant strain (IC50 = 3.44 µM to 19.11 µM). Three of them (dehydrobufotenine, marinobufagin, and bufalin) showed adequate conditions for oral drug prototypes, with satisfactory prediction of absorption, permeability, and absence of toxicity. In the cell viability assay, only dehydrobufotenin was selective for the parasite. Conclusions: Dehydrobufotenin revealed to be a potential oral drug prototype presenting adequate antimalarial activity and absence of cytotoxicity, therefore should be subjected to further studies.(AU)

Electrocardiographic effect of artemisinin-piperaquine, dihydroartemisinin-piperaquine, and artemether-lumefantrine treatment in falciparum malaria patients

Abstract INTRODUCTION: Artemisinin-based combination therapy (ACT), such as artemisinin-piperaquine (AP), dihydroartemisinin-piperaquine (DP), and artemether-lumefantrine (AL), is the first-line treatment for malaria in many malaria-endemic areas. However, we lack a detailed evaluation of the cardiotoxicity of these ACTs. This study aimed to analyze the electrocardiographic effects of these three ACTs in malaria patients. METHODS: We analyzed the clinical data of 89 hospitalized patients with falciparum malaria who had received oral doses of three different ACTs. According to the ACTs administered, these patients were divided into three treatment groups: 27 treated with AP (Artequick), 31 with DP (Artekin), and 31 with AL (Coartem). Electrocardiograms and other indicators were recorded before and after the treatment. The QT interval was calculated using Fridericia's formula (QTcF) and Bazett's formula (QTcB). RESULTS: Both QTcF and QTcB interval prolongation occurred in all three groups. The incidence of such prolongation between the three groups was not significantly different. The incidence of both moderate and severe prolongation was not significantly different between the three groups. The ΔQTcF and ΔQTcB of the three groups were not significantly different. The intra-group comparison showed significant prolongation of QTcF after AL treatment. CONCLUSIONS: Clinically recommended doses of DP, AL, and AP may cause QT prolongation in some malaria patients but do not cause torsades de pointes ventricular tachycardia or other arrhythmias.

Quinolinotriazole antiplasmodials via click chemistry: synthesis and in vitro studies of 7-Chloroquinoline-based compounds

Malaria is nowadays one of the most serious health concerns in a global scale and, although there is an evident increase in research studies in this area, pointed by the vast number of hits and leads, it still appears as a recurrent topic every year due to the drug resistance shown by the parasite exposing the urgent need to develop new antimalarial medications. In this work, 38 molecules were synthesized via copper(I)-catalyzed alkyne-azide cycloaddition (CuAAC) or "click" chemistry, following different routes to produce 2 different organic azides, obtained from a 4,7 dicholoquinoline, reacted with 19 different commercially available terminal alkynes. All those new compounds were evaluated for their in vitro activity against the chloroquine resistant malaria parasite Plasmodium falciparum (W2). The cytotoxicity evaluation was accomplished using Hep G2 cells and SI index was calculated for every molecule. Some of the quinoline derivatives have shown high antimalarial activity, with IC50 values in the range of 1.72-8.66 µM, low cytotoxicity, with CC50>1000 µM and selectivity index (SI) in the range of 20-100, with some compounds showing SI>800. Therefore, the quinolinotriazole hybrids could be considered a very important step on the development of new antimalarial drugs

Preparation and Physicochemical Evaluation of Lumefantrine-2-Hydroxypropyl-β-cyclodextrin Binary Systems

Lumefantrine contributes significant roles in artemisinin-based combination therapy for malaria treatment but associated with a limitation of poor aqueous solubility and low permeability. This study investigated lumefantrine-2-hydroxypropyl-β-cyclodextrin complex to improve its solubility profile. A phase-solubility analysis and molecular modelling were carried out before the preparation of the complex by physical mixture, kneading, co-evaporation and freeze-drying methods. Fourier transform infrared (FT-IR) spectroscopic and powder X-ray diffractometric (PXRD) techniques were used to characterised the complex. The phase-solubility studies showed a type AL diagram with an apparent stability constant value of 243.4 M-1suggesting the formation of a soluble and stable complex. Significant improvements in aqueous solubility was achieved, notably the freeze

Caracterización clínica del paludismo importado / Clinical characterization of imported malaria

Introducción: El paludismo es una enfermedad febril aguda potencialmente mortal causada por parásitos que se transmiten al ser humano por la picadura de mosquitos del género Anopheles. Cuba logró eliminar la transmisión de esta enfermedad gracias a grandes esfuerzos encaminados a conseguirlo, por lo que es necesario adoptar una serie de medidas para evitar su reaparición, mediante la vigilancia y el Programa de Control Sanitario Internacional. Objetivo: Caracterizar clínicamente un grupo de pacientes con paludismo importado. Métodos: Se realizó un estudio descriptivo de corte transversal de 46 pacientes adultos con paludismo importado, ingresados en el Instituto de Medicina Tropical Pedro Kourí desde enero 2015 a diciembre 2016. Los datos fueron tomados de las historias clínicas. El análisis de las variables cualitativas fue expresado en tablas de frecuencias absolutas y relativas. Resultados: Predominaron los pacientes del sexo masculino, con una edad media de 37,4 años. Entre los pacientes, 38 (82,6 por ciento) arribaron del continente africano, la mayoría de ellos de Angola (26,1 por ciento del total de casos). Fue significativa la relación existente entre el supuesto estado no inmune de los pacientes con la severidad del cuadro clínico y presencia de comorbilidades; así como la severidad del cuadro clínico con mayor parasitemia y la especie Plasmodium falciparum. La respuesta al tratamiento resultó excelente con los esquemas combinados utilizados a base de quinina y cloroquina según la especie. Conclusiones: La demora desde el arribo al ingreso hospitalario de los pacientes constituye un riesgo extraordinario para la reintroducción del paludismo en Cuba y para la vida de estos(AU)

Introduction: Malaria is an acute potentially fatal febrile disease caused by parasites transmitted to humans through the bite of mosquitoes from the genus Anopheles. Cuba succeeded in eliminating transmission of this disease thanks to great efforts geared to such an end. It is therefore necessary to take a number of measures aimed at preventing its re-emergence via surveillance and the International Health Control Program. Objective: Clinically characterize a group of patients with imported malaria. Methods: A descriptive cross-sectional study was conducted of 46 adult patients with imported malaria admitted to Pedro Kourí Tropical Medicine Institute from January 2015 to December 2016. The data were collected from the patients' medical records. Results of the analysis of qualitative variables were transferred onto absolute and relative frequency tables. Results: Male patients prevailed, with a mean age of 37.4 years. Of the patients studied, 38 (82.6 percent) were from the African continent, most of them from Angola (26.1 percent of the total cases). A significant relationship was found between the supposed non-immune status of patients and the severity of the clinical status and the presence of comorbidities, as well as between the severity of the clinical status and greater parasitemia and the presence of the species Plasmodium falciparum. An excellent response was obtained to treatment with combined schemes based on quinine and chloroquine, depending on the species. Conclusions: Delay between arrival and hospital admittance of patients is an extraordinary risk for the reintroduction of malaria in Cuba and to the patients' lives(AU)