Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
Más filtros












Intervalo de año de publicación
1.
Polymers (Basel) ; 14(24)2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36559869

RESUMEN

Artemether (ATM) is an effective antimalarial drug that also has a short half-life in the blood. Furthermore, ATM is also cardiotoxic and is associated with pro-arrhythmogenic risks. We aimed to develop a delivery system enabling the prolonged release of ATM into the blood coupled with reduced cardiotoxicity. To achieve this, we prepared polymeric nanocapsules (NCs) from different biodegradable polyesters, namely poly(D,L-lactide) (PLA), poly-ε-caprolactone (PCL), and surface-modified NCs, using a monomethoxi-polyethylene glycol-block-poly(D,L-lactide) (PEG5kDa-PLA45kDa) polymer. Using this approach, we were able to encapsulate high yields of ATM (>85%, 0−4 mg/mL) within the oily core of the NCs. The PCL-NCs exhibited the highest percentage of ATM loading as well as a slow release rate. Atomic force microscopy showed nanometric and spherical particles with a narrow size dispersion. We used the PCL NCs loaded with ATM for biological evaluation following IV administration. As with free-ATM, the ATM-PCL-NCs formulation exhibited potent antimalarial efficacy using either the "Four-day test" protocol (ATM total at the end of the 4 daily doses: 40 and 80 mg/kg) in Swiss mice infected with P. berghei or a single low dose (20 mg/kg) of ATM in mice with higher parasitemia (15%). In healthy rats, IV administration of single doses of free-ATM (40 or 80 mg/kg) prolonged cardiac QT and QTc intervals and induced both bradycardia and hypotension. Repeated IV administration of free-ATM (four IV doses at 20 mg/kg every 12 h for 48 h) also prolonged the QT and QTc intervals but, paradoxically, induced tachycardia and hypertension. Remarkably, the incorporation of ATM in ATM-PCL-NCs reduced all adverse effects. In conclusion, the encapsulation of ATM in biodegradable polyester NCs reduces its cardiovascular toxicity without affecting its antimalarial efficacy.

2.
Arch Pharm (Weinheim) ; 355(9): e2200004, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35621705

RESUMEN

For the first time, compounds developed from the 1,2,3-triazole scaffold were evaluated as novel drugs to treat triple-negative breast cancer (TNBC). Four organic salts were idealized as nonclassical bioisosteres of miltefosine, which is used in the topical treatment for skin metastasizing breast carcinoma. Among them, derivative dhmtAc displayed better solubility and higher cytotoxicity against the human breast adenocarcinoma cell line and mouse 4T1 cell lines, which are representatives of TNBC. In vitro assays revealed that dhmtAc interferes with cell integrity, confirmed by lactate dehydogenase leakage. Due to its human peripheral blood mononuclear cell (PBMC) toxicity, dhmtAc in vivo studies were carried out with the drug incorporated in a long-circulating and pH-sensitive liposome (SpHL-dhmtAc), and the acute toxicity in BALB/c mice was determined. Free dhmtAc displayed cardiac and pulmonary toxicity after the systemic administration of 5 mg/kg doses. On the other hand, SpHL-dhmtAc displayed no toxicity at 20 mg/kg. The in vivo antitumor effect of SpHL-dhmtAc was investigated using the 4T1 heterotopic murine model. Intravenous administration of SpHL-dhmtAc reduced the tumor volume and weight, without interfering with the body weight, compared with the control group and the dhmtAc free form. The incorporation of the triazole compound in the liposome allowed the demonstration of its anticancer potential. These findings evidenced 1,3,4-trisubstituted-1,2,3-triazole as a promising scaffold for the development of novel drugs with applicability for the treatment of patients with TNBC.


Asunto(s)
Liposomas , Neoplasias de la Mama Triple Negativas , Animales , Línea Celular Tumoral , Humanos , Leucocitos Mononucleares , Ratones , Ratones Endogámicos BALB C , Relación Estructura-Actividad , Triazoles/farmacología , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico
3.
Prostaglandins Other Lipid Mediat ; 159: 106622, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35091082

RESUMEN

The incidence of cardiovascular diseases and metabolic disorders has increased worldwide. Clinical and experimental research has shown that the consumption of ω-3 FAs can be beneficial to metabolism in several ways, as they can act on metabolic pathways. Our objective was to evaluate the effect of treatment with linseed oil, a vegetable oil rich in alpha-linolenic acid, and EPA and DHA in different proportions (3:1 EPA:DHA, and 1:3 EPA:DHA), on the metabolic disorders induced by a high-fat diet (20 % lipids) in rats for 2 weeks, after 18 weeks of consumption of a high-fat diet. In 18 weeks, the high-fat diet increased blood glucose, systolic blood pressure, triglyceride concentration in the liver and adipose tissue, and impaired insulin sensibility without interfering in the weight of the animals. All treatments were effective in reducing the deposition of hepatic type III collagen, the proportion of ω-6/ω-3 in the liver and WAT (white adipose tissue), the proportion of area/number of adipocytes, and the gene expression of the ACC, FAS, and CPT1 enzymes. In addition, treatment with EPA and DHA reduced blood glucose, serum TNF-α concentration, amount of liver fat, degree of microsteatosis and type I collagen deposition in the liver, deposition of type I and III collagen in TA, gene expression of the transcription factor SREBP-1c, and increased hepatic binucleation. EPA in major proportion was more effective in reducing the area of adipocytes, hepatic triglyceride concentration, PPAR-α expression, and WAT fat weight. DHA in a major proportion reduced the concentration of MCP1 in WAT. LO treatment did not have any isolated effects. We concluded that EPA and DHA were more effective in treating metabolic damage than treatment with LO, leading to a more favorable metabolic profile.


Asunto(s)
Dieta Alta en Grasa , Ácidos Grasos Omega-3 , Tejido Adiposo/metabolismo , Animales , Glucemia/metabolismo , Dieta Alta en Grasa/efectos adversos , Ácidos Docosahexaenoicos/metabolismo , Ácidos Docosahexaenoicos/farmacología , Ácido Eicosapentaenoico/metabolismo , Ácido Eicosapentaenoico/farmacología , Ácidos Grasos Omega-3/metabolismo , Ácidos Grasos Omega-3/farmacología , Aceite de Linaza/farmacología , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratas , Triglicéridos/metabolismo
4.
Pharmaceutics ; 13(9)2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34575597

RESUMEN

Lyso-7 is a novel synthetic thiazolidinedione, which is a receptor (pan) agonist of PPAR α,ß/δ,γ with anti-inflammatory activity. We investigated the cardiotoxicity of free Lyso-7 in vitro (4.5-450 nM), and Lyso-7 loaded in polylactic acid nanocapsules (NC) in vivo (Lyso-7-NC, 1.6 mg/kg). In previous work, we characterized Lyso-7-NC. We administered intravenously Lyso-7, Lyso-7-NC, control, and blank-NC once a day for seven days in mice. We assessed cell contraction and intracellular Ca2+ transients on single mice cardiomyocytes enzymatically isolated. Lyso-7 reduced cell contraction and accelerated relaxation while lowering diastolic Ca2+ and reducing Ca2+ transient amplitude. Lyso-7 also promoted abnormal ectopic diastolic Ca2+ events, which isoproterenol dramatically enhanced. Incorporation of Lyso-7 in NC attenuated drug effects on cell contraction and prevented its impact on relaxation, diastolic Ca2+, Ca2+ transient amplitude, Ca2+ transient decay kinetics, and promotion of diastolic Ca2+ events. Acute effects of Lyso-7 on cardiomyocytes in vitro at high concentrations (450 nM) were globally similar to those observed after repeated administration in vivo. In conclusion, we show evidence for off-target effects of Lyso-7, seen during acute exposure of cardiomyocytes to high concentrations and after repeated treatment in mice. Nano-encapsulation of Lyso-7 in polymeric NC attenuated the unwanted effects, particularly ectopic Ca2+ events known to support life-threatening arrhythmias favored by stress or exercise.

5.
Clin Exp Hypertens ; 43(6): 536-549, 2021 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-33870805

RESUMEN

Background: Left ventricular hypertrophy (LVH) is an endpoint of hypertensive cardiac alterations. Renin-angiotensin-aldosterone system (RAAS) blockers are among the most effective on LVH regression. Physical exercise combined to antihypertensive drug contributes to arterial pressure (AP) control and LVH prevention. We evaluated the effects of physical exercise combined to captopril or losartan during eight weeks for spontaneously hypertensive rats (SHR) on some cardiac parameters.Methods: SHR (n=5-6 per group) were sedentary or trained 5 days a week in treadmill during 8 weeks; and they were treated with daily oral captopril (12.5, 25, or 50mg/kg), losartan (2.5, 5, or 10mg/kg), or vehicle. At the end, it was obtained systolic AP (SAP), electrocardiogram (ECG), and hearts metalloproteinase 2 (MMP-2) activity and histology.Results: Captopril 25 and 50 mg/kg, and losartan 10 mg/kg lowered SAP of sedentary and trained SHR. Losartan 5 mg/kg combined with physical exercise also lowered SAP. Combined with exercise, captopril 50 mg/kg lowered 13.6% of QT interval, 14.2% of QTc interval, and 22.8% of Tpeak-Tend compared to sedentary SHR. Losartan 5 and 10mg/kg lowered QT interval of sedentary and trained SHR. Losartan 2.5, 5 and 10mg/kg combined with physical exercise lowered respectively 25.4%, 24.8%, and 31.8% of MMP-2 activity. Losartan (10mg/kg) combined with exercise reduced cardiomyocyte diameter.Conclusion: These data support the hypothesis of physical exercise combined with RAAS blockers could improve the benefits on hypertensive LVH treatment.


Asunto(s)
Hipertensión , Hipertrofia Ventricular Izquierda , Losartán , Animales , Antihipertensivos/farmacología , Antihipertensivos/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Captopril/farmacología , Hipertensión/tratamiento farmacológico , Hipertrofia Ventricular Izquierda/prevención & control , Losartán/farmacología , Metaloproteinasa 2 de la Matriz/farmacología , Ratas , Ratas Endogámicas SHR
6.
ABCS health sci ; 46: e021306, 09 fev. 2021. ilus
Artículo en Inglés | LILACS | ID: biblio-1343364

RESUMEN

Coronaviruses (CoVs) belong to the family Coronaviridae, which are enveloped and have a single-stranded RNA genome. The new coronavirus (SARS-CoV-2) is the seventh known coronavirus that can infect humans and cause serious illness, such as acute respiratory syndrome. The coronaviruses already identified have contributed to the understanding of the clinical manifestations caused by SARSCoV-2, as well as their associations with the immune system. The aim of the present study was to carry out a narrative review of the literature on the host's immune response to infection by the new coronavirus. The review contains basic and summarized information on the main mechanisms involved in the immune response to SARS-CoV-2. The characteristics of the infection were considered according to the following: from the initial contact with the host through binding to angiotensin-converting enzyme 2 (ACE-2); the recognition of the pathogen by innate immunity cells; its containment mechanisms, including the production of effector cytokines and chemokines important in the development of the inflammatory process; and the participation of the complement system until the activation of the adaptive immune response. The probable occurrence of a host dysfunctional immune response and the escape mechanisms of the virus were also addressed. Despite numerous studies on the pathogenesis of SARS-CoV-2 infection, knowledge about the host's immune response in COVID-19 is not fully understood. The present work established the relationship between the new coronavirus and the immune system, but further studies are needed for all the mechanisms of the process to be elucidated.


Os coronavírus (CoVs) pertencem à família Coronaviridae, são envelopados com genoma de RNA (Ácido Ribonucleico) de fita simples e de sentido positivo. O novo coronavírus (SARS-CoV-2) é o sétimo coronavírus conhecido com capacidade de infectar seres humanos e pode provocar doença grave, como a síndrome respiratória aguda. Os coronavírus já identificados contribuíram para o entendimento das manifestações clínicas causadas pelo SARS-CoV-2, bem como suas correlações com o sistema imune. O presente trabalho teve o propósito de realizar uma revisão narrativa de literatura sobre a resposta imune do hospedeiro à infecção pelo novo coronavírus. A revisão contém informações básicas e resumidas dos principais mecanismos envolvidos na resposta imune ao SARS-CoV-2. Foram consideradas as características da infecção desde o contato inicial com o hospedeiro, por meio da ligação da Enzima Conversora de Angiotensina 2 (ECA2), o reconhecimento do patógeno pelas células da imunidade inata, seus mecanismos de contenção, incluindo a produção de citocinas efetoras e quimiocinas importantes no desenvolvimento do processo inflamatório, a participação do sistema complemento até a ativação da resposta imune adaptativa. Foram abordados também a provável ocorrência de uma resposta imune disfuncional do hospedeiro e os mecanismos de escape do vírus. Apesar dos inúmeros trabalhos sobre a patogenia da infecção pelo SARS-CoV-2, o conhecimento sobre a resposta imune do hospedeiro na COVID-19 não está totalmente esclarecido. O presente trabalho estabeleceu as relações do novo coronavírus com o sistema imunológico, entretanto, mais estudos ainda são necessários para que todos os mecanismos do processo sejam elucidados.


Asunto(s)
Síndrome Respiratorio Agudo Grave , SARS-CoV-2 , COVID-19/inmunología , Inmunidad
7.
Cardiovasc Toxicol ; 21(2): 93-105, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32845461

RESUMEN

Caspofungin is an echinocandin, exhibiting efficacy against most Candida species invasive infection. Its cardiotoxicity was reported in isolated rat heart and ventricular myocytes, but in vivo and clinical studies are insufficient. Our objective was to evaluate caspofungin in vivo cardiac effects using an efficacious dose against Candida albicans. Female Swiss mice were infected with C. albicans, and treated with caspofungin, 5 or 10 mg/kg, intraperitoneal along 5 days. Survival rate and colony-forming units (CFU) into vital organs were determined. For cardiac effects study, mice were treated with caspofungin 10 mg/kg, and electrocardiogram (ECG) signal was obtained on C. albicans-infected mice, single dose-treated, and uninfected mice treated along 5 days, both groups to measure ECG intervals. Besides, ECG was also obtained by telemetry on uninfected mice to evaluate heart rate variability (HRV) parameters. The MIC for caspofungin on the wild-type C. albicans SC5314 strain was 0.3 µg/ml, indicating the susceptible. Survival rate increased significantly in infected mice treated with caspofungin compared to mice treated with vehicle. None of the survived infected mice presented positive CFU after treatment with 10 mg/kg. C. albicans infection induced prolongation of QRS, QT, and QTc intervals; caspofungin did not alter this effect. Caspofungin induced increase of PR and an additional increase of QRS after 24 h of a single dose in infected mice. No significant alterations occurred in ECG intervals and HRV parameters of uninfected mice, after caspofungin treatment. Caspofungin showed in vivo cardiac relative safety maintaining its antifungal efficacy against C. albicans.


Asunto(s)
Antifúngicos/farmacología , Candida albicans/efectos de los fármacos , Candidiasis/tratamiento farmacológico , Caspofungina/farmacología , Frecuencia Cardíaca/efectos de los fármacos , Corazón/efectos de los fármacos , Animales , Antifúngicos/toxicidad , Candida albicans/patogenicidad , Candidiasis/microbiología , Cardiotoxicidad , Caspofungina/toxicidad , Modelos Animales de Enfermedad , Electrocardiografía , Femenino , Corazón/fisiopatología , Ratones , Pruebas de Sensibilidad Microbiana , Medición de Riesgo , Pruebas de Toxicidad
8.
An Acad Bras Cienc ; 92(4): e20201593, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33295585

RESUMEN

The increase in the number of studies related to the health of university students has attracted attention at the time of COVID-19. This initiative contributes to preparing the school environment for the return of face-to-face activities with conducts that minimize the damage caused by the pandemic. The role of each actor in the educational scenario is fundamental for us to be able to reap good fruits after this storm.


Asunto(s)
Betacoronavirus , COVID-19 , Infecciones por Coronavirus , Neumonía Viral , Infecciones por Coronavirus/epidemiología , Humanos , Pandemias , Neumonía Viral/epidemiología , SARS-CoV-2
9.
High Blood Press Cardiovasc Prev ; 27(6): 493-503, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32776302

RESUMEN

INTRODUCTION: Physical exercise and antihypertensive drugs contribute to reduce or prevent hypertensive heart disease (HHD). The effect on blood pressure (BP) of both combined therapy is well documented, but not for the left ventricular (LV) function. AIM: A systematic review and meta-analysis was conducted for LV biomarkers analysis regarding to HHD on subjects treated with antihypertensive drugs combined with physical exercise practice. METHODS: The search was conducted on the Pubmed, Bireme, Lilacs, Central (Cochrane) and Science direct databases, comprising undetermined period of time, including randomized studies comparing trained and sedentary subjects, both treated with antihypertensive drugs. We analyzed the influence of combined therapy on echocardiogram parameters and BP. A significance level of 5% and 95% CI was considered for all outcomes. RESULTS: Five studies (N = 1738) were included in meta-analysis. Combined therapy decreased significantly LV mass (CI - 21.63 to - 1.81, N = 783) and heart rate (HR; CI - 4.23 to - 1.59, N = 1738), compared to antihypertensive drugs alone. There was a trend to decrease LV mass index (LVMI; CI - 5.57 to 0.71, N = 1674), systolic BP (CI - 2.47 to 1.23, N = 1674) and diastolic BP (CI - 2.16 to 0.28, N = 1674), a trend to increase of ejection fraction (EF; 95% CI - 0.50 to 2.12, N = 783) and LV end-diastolic diameter (CI - 0.85 to 0.92, N = 847) was similar. CONCLUSION: The antihypertensive therapy combined with physical exercise practice can reduce LV mass and HR. Therefore, combined therapy prescription should be considered for prevention and treatment of LV hypertrophy of hypertensive subjects.


Asunto(s)
Antihipertensivos/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Terapia por Ejercicio , Hipertensión/terapia , Hipertrofia Ventricular Izquierda/prevención & control , Función Ventricular Izquierda/efectos de los fármacos , Remodelación Ventricular/efectos de los fármacos , Anciano , Terapia Combinada , Femenino , Humanos , Hipertensión/epidemiología , Hipertensión/fisiopatología , Hipertrofia Ventricular Izquierda/epidemiología , Hipertrofia Ventricular Izquierda/fisiopatología , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
10.
Br J Pharmacol ; 177(19): 4448-4463, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32608017

RESUMEN

BACKGROUND AND PURPOSE: The artemisinin derivative, artemether, has antimalarial activity with potential neurotoxic and cardiotoxic effects. Artemether in nanocapsules (NC-ATM) is more efficient than free artemether for reducing parasitaemia and increasing survival of Plasmodium berghei-infected mice. NCs also prevent prolongation of the QT interval of the ECG. Here, we assessed cellular cardiotoxicity of artemether and how this toxicity was prevented by nanoencapsulation. EXPERIMENTAL APPROACH: Mice were treated with NC-ATM orally (120 mg·kg-1 twice daily) for 4 days. Other mice received free artemether, blank NCs, and vehicle for comparison. We measured single-cell contraction, intracellular Ca2+ transient using fluorescent Indo-1AM Ca2+ dye, and electrical activity using the patch-clamp technique in freshly isolated left ventricular myocytes. The acute effect of free artemether was also tested on cardiomyocytes of untreated animals. KEY RESULTS: Artemether prolonged action potentials (AP) upon acute exposure (at 0.1, 1, and 10 µM) of cardiomyocytes from untreated mice or after in vivo treatment. This prolongation was unrelated to blockade of K+ currents, increased Ca2+ currents or promotion of a sustained Na+ current. AP lengthening was abolished by the NCX inhibitor SEA-0400. Artemether promoted irregular Ca2+ transients during pacing and spontaneous Ca2+ events during resting periods. NC-ATM prevented all effects. Blank NCs had no effects compared with vehicle. CONCLUSION AND IMPLICATIONS: Artemether induced NCX-dependent AP lengthening (explaining QTc prolongation) and disrupted Ca2+ handling, both effects increasing pro-arrhythmogenic risks. NCs prevented these adverse effects, providing a safe alternative to the use of artemether alone, especially to treat malaria.


Asunto(s)
Calcio , Miocitos Cardíacos , Potenciales de Acción , Animales , Arritmias Cardíacas , Arteméter , Calcio/metabolismo , Ratones , Miocitos Cardíacos/metabolismo , Técnicas de Placa-Clamp , Intercambiador de Sodio-Calcio
11.
Parasitology ; 145(8): 1075-1083, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29223181

RESUMEN

Artemether (ATM) cardiotoxicity, its short half-life and low oral bioavailability are the major limiting factors for its use to treat malaria. The purposes of this work were to study free-ATM and ATM-loaded poly-ε-caprolactone nanocapules (ATM-NC) cardiotoxicity and oral efficacy on Plasmodium berghei-infected mice. ATM-NC was obtained by interfacial polymer deposition and ATM was associated with polymeric NC oily core. For cardiotoxicity evaluation, male black C57BL6 uninfected or P. berghei-infected mice received, by oral route twice daily/4 days, vehicle (sorbitol/carboxymethylcellulose), blank-NC, free-ATM or ATM-NC at doses 40, 80 or 120 mg kg-1. Electrocardiogram (ECG) lead II signal was obtained before and after treatment. For ATM efficacy evaluation, female P. berghei-infected mice were treated the same way. ATM-NC improved antimalarial in vivo efficacy and reduced mice mortality. Free-ATM induced significantly QT and QTc intervals prolongation. ATM-NC (120 mg kg-1) given to uninfected mice reduced QT and QTc intervals prolongation 34 and 30%, respectively, compared with free-ATM. ATM-NC given to infected mice also reduced QT and QTc intervals prolongation, 28 and 27%, respectively. For the first time, the study showed a nanocarrier reducing cardiotoxicity of ATM given by oral route and it was more effective against P. berghei than free-ATM as monotherapy.


Asunto(s)
Antimaláricos/administración & dosificación , Arteméter/administración & dosificación , Cardiotoxicidad/prevención & control , Nanocápsulas/química , Plasmodium berghei/efectos de los fármacos , Administración Oral , Animales , Antimaláricos/toxicidad , Arteméter/toxicidad , Modelos Animales de Enfermedad , Electrocardiografía , Femenino , Malaria/tratamiento farmacológico , Masculino , Ratones , Ratones Endogámicos C57BL
12.
Life Sci ; 187: 42-49, 2017 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-28823565

RESUMEN

AIM: Investigate to what extent low-intensity swim training for six weeks counterbalances the adverse remodeling due to the advance of pathological hypertrophy in the left ventricle (LV) structural and mechanical properties in the early compensated phase of hypertension in male SHR. MAIN METHODS: Four-month-old male SHR and Wistar rats were randomly divided into Sed (sedentary) and Ex (exercised) groups. The exercised rats were submitted to a swimming protocol (1h/day, 5times/week, no additional load) for six weeks. LV tissue and isolated myocytes were used to assess structural and mechanical properties. Myocytes were stimulted at frequencies (F) of 1 and 3Hz at 37°C. KEY FINDINGS: Exercised SHR showed improvement in cardiovascular parameters compared to sedentary SHR (mean arterial pressure: 13.22%; resting HR: 14.28.%). About structural and mechanical properties, swim training induced a decrease in LV myocyte thickness (10.85%), number of inflammatory cells (21.24%); collagen type III (74.23%) and type I (85.6%) fiber areas; amplitude of single myocyte shortening (47% to F1 and 28.46% to F3), timecourses of shortening (16.5% to F1 and 7.55% to F3) and relaxation (15.31% to F3) compared to sedentary SHR. SIGNIFICANCE: Six weeks of swim training attenuates the adverse remodeling of LV structural and mechanical properties in the early compensated phase of hypertension in male SHR.


Asunto(s)
Ventrículos Cardíacos/patología , Hipertensión/patología , Hipertensión/terapia , Modalidades de Fisioterapia , Natación , Remodelación Ventricular/fisiología , Animales , Presión Sanguínea/fisiología , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Estimulación Eléctrica , Frecuencia Cardíaca/fisiología , Ventrículos Cardíacos/metabolismo , Hipertensión/metabolismo , Hipertensión/fisiopatología , Hipertrofia , Masculino , Contracción Muscular/fisiología , Relajación Muscular/fisiología , Miocitos Cardíacos/patología , Miocitos Cardíacos/fisiología , Condicionamiento Físico Animal , Ratas
13.
Respir Physiol Neurobiol ; 243: 107-114, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28624507

RESUMEN

The current work was conducted to verify the contribution of neuromuscular transmission defects at the neuromuscular junction to Duchenne Muscular Dystrophy disease progression and respiratory dysfunction. We tested pyridostigmine and pyridostigmine encapsulated in liposomes (liposomal PYR), an acetylcholinesterase inhibitor to improve muscular contraction on respiratory muscle function in mdx mice at different ages. We evaluated in vivo with the whole-body plethysmography, the ventilatory response to hypercapnia, and measured in vitro diaphragm strength in each group. Compared to C57BL10 mice, only 17 and 22 month-old mdx presented blunted ventilatory response, under normocapnia and hypercapnia. Free pyridostigmine (1mg/kg) was toxic to mdx mice, unlike liposomal PYR, which did not show any side effect, confirming that the encapsulation in liposomes is effective in reducing the toxic effects of this drug. Treatment with liposomal PYR, either acute or chronic, did not show any beneficial effect on respiratory function of this DMD experimental model. The encapsulation in liposomes is effective to abolish toxic effects of drugs.


Asunto(s)
Inhibidores de la Colinesterasa/farmacología , Distrofia Muscular de Duchenne/complicaciones , Bromuro de Piridostigmina/farmacología , Trastornos Respiratorios , Músculos Respiratorios/efectos de los fármacos , Factores de Edad , Animales , Inhibidores de la Colinesterasa/uso terapéutico , Modelos Animales de Enfermedad , Sistemas de Liberación de Medicamentos , Técnicas In Vitro , Liposomas/uso terapéutico , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos mdx , Contracción Muscular/efectos de los fármacos , Distrofia Muscular de Duchenne/genética , Distrofia Muscular de Duchenne/patología , Pletismografía , Bromuro de Piridostigmina/uso terapéutico , Trastornos Respiratorios/tratamiento farmacológico , Trastornos Respiratorios/etiología , Trastornos Respiratorios/patología , Frecuencia Respiratoria/efectos de los fármacos , Espectrofotometría Ultravioleta , Volumen de Ventilación Pulmonar/efectos de los fármacos
14.
Sci Rep ; 7: 44998, 2017 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-28349937

RESUMEN

Chagas disease is a neglected parasitic disease caused by the protozoan Trypanosoma cruzi. New antitrypanosomal options are desirable to prevent complications, including a high rate of cardiomyopathy. Recently, a natural substance, lychnopholide, has shown therapeutic potential, especially when encapsulated in biodegradable polymeric nanocapsules. However, little is known regarding possible adverse effects of lychnopholide. Here we show that repeated-dose intravenous administration of free lychnopholide (2.0 mg/kg/day) for 20 days caused cardiopathy and mortality in healthy C57BL/6 mice. Echocardiography revealed concentric left ventricular hypertrophy with preserved ejection fraction, diastolic dysfunction and chamber dilatation at end-stage. Single cardiomyocytes presented altered contractility and Ca2+ handling, with spontaneous Ca2+ waves in diastole. Acute in vitro lychnopholide application on cardiomyocytes from healthy mice also induced Ca2+ handling alterations with abnormal RyR2-mediated diastolic Ca2+ release. Strikingly, the encapsulation of lychnopholide prevented the cardiac alterations induced in vivo by the free form repeated doses. Nanocapsules alone had no adverse cardiac effects. Altogether, our data establish lychnopholide presented in nanocapsule form more firmly as a promising new drug candidate to cure Chagas disease with minimal cardiotoxicity. Our study also highlights the potential of nanotechnology not only to improve the efficacy of a drug but also to protect against its adverse effects.


Asunto(s)
Materiales Biocompatibles , Cardiotónicos/farmacología , Lactonas/efectos adversos , Nanocápsulas , Polímeros , Sesquiterpenos/efectos adversos , Tripanocidas/efectos adversos , Trypanosoma cruzi/efectos de los fármacos , Animales , Materiales Biocompatibles/química , Calcio/metabolismo , Señalización del Calcio/efectos de los fármacos , Cardiotónicos/química , Cardiotoxicidad , Enfermedad de Chagas/diagnóstico , Enfermedad de Chagas/tratamiento farmacológico , Enfermedad de Chagas/mortalidad , Enfermedad de Chagas/parasitología , Ecocardiografía , Masculino , Ratones , Imagen Molecular , Mortalidad , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Nanocápsulas/química , Polímeros/química
15.
Pharm Dev Technol ; 19(4): 454-9, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23682846

RESUMEN

Pyridostigmine has cardioprotective activity in both free and liposomal forms. This study aimed to develop and characterize liposomal formulations of pyridostigmine. For this, a spectrophotometric ultraviolet (UV) analytical method, at 270 nm, was developed and validated to quantify liposomal pyridostigmine. The method was linear in ranges from 0.02 to 0.09 mg/mL. The accuracy of this method was determined intra- and inter-day; the results of coefficient of variation were of 1.73-2.72% and 0.32-2.32%, respectively. The accuracy ranged between 99.45% and 101.12%. The method has not changed by influence of liposomal matrix and demonstrated being able to quantify pyridostigmine in liposomes. Two liposomal multilamellar formulations were developed: a constituted by dystearoyl-phosphatidylcholine (DSPC) and cholesterol (CHOL) other by dioleil-phosphatidylcholine (DOPC) and CHOL. The encapsulation efficiency was determined as 23.4% and 15.4%, respectively. Analyses of size and release of pyridostigmine from the formulations were made and the results showed that the formulations are viable for future studies in vivo.


Asunto(s)
Liposomas/química , Bromuro de Piridostigmina/química , Química Farmacéutica/métodos , Colesterol/química , Portadores de Fármacos/química , Tamaño de la Partícula , Fosfatidilcolinas/química
16.
Phytother Res ; 27(3): 384-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22619042

RESUMEN

The aerial parts of Lychnophora trichocarpha Spreng. (Asteraceae) are used macerated in water or ethanol to treat inflammation, pain, rheumatism, contusions, bruises and insect bites in Brazilian traditional medicine. In this study, anti-inflammatory activity of ethanol extract from aerial parts of L. trichocarpha and its ethyl acetate fraction was investigated. Sesquiterpene lactones, lychnopholide (Lyc) and eremantholide C (EreC), isolated of ethyl acetate fraction, were also assayed for in vitro and in vivo anti-inflammatory activity. Topical treatment with ointments containing ethanol extract, its ethyl acetate fraction and sesquiterpene lactones significantly reduced carrageenan-induced mice paw oedema. In vitro assays demonstrated that Lyc inhibited interferon -γ/lipopolysaccharide -stimulated nitric oxide (NO) production in J774A.1 macrophages and increased production of IL-10 anti-inflammatory cytokine. The reduction of tumor necrosis factor-α (TNF-α) production by EreC was accompanied by an increased production of IL-10 in a concentration-dependent manner in J774A.1 macrophages. The anti-inflammatory effect of Lyc seems to involve the inhibition of production of NO and increased production of IL-10. The mechanism of the effect of EreC on the reduction of carrageenan-induced paw oedema may be attributed to inhibition of production of TNF-α and stimulation of IL-10 production. The results corroborate the use of ethanol extract from Lychnophora trichocarpha in folk medicine for anti-inflammatory action and indicate that the topical route is suitable for use.


Asunto(s)
Antiinflamatorios/farmacología , Asteraceae/química , Edema/tratamiento farmacológico , Lactonas/farmacología , Extractos Vegetales/farmacología , Sesquiterpenos/farmacología , Animales , Antiinflamatorios/aislamiento & purificación , Carragenina/efectos adversos , Línea Celular , Edema/inducido químicamente , Interleucina-10/inmunología , Lactonas/aislamiento & purificación , Macrófagos/efectos de los fármacos , Masculino , Ratones , Óxido Nítrico/inmunología , Sesquiterpenos/aislamiento & purificación , Factor de Necrosis Tumoral alfa/inmunología
17.
J Ethnopharmacol ; 145(1): 100-8, 2013 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-23123269

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Campomanesia species are used in folk medicine as anti-inflammatory, anti-rheumatic, anti-diarrheal and hypocholesterolemic. AIM OF THE STUDY: The present study investigated the in vivo anti-inflammatory and antinociceptive properties of ethyl acetate (AE) and aqueous (Aq) extracts from leaves of Campomanesia adamantium and in vitro anti-inflammatory activity of AE and its isolated flavonols, myricitrin and myricetin. MATERIALS AND METHODS: The antinociceptive activity of AE and Aq was evaluated using acetic acid-induced writhing and formalin methods. The in vivo anti-inflammatory effect of AE and Aq was evaluated using carrageenan-induced paw oedema in mice. AE, myricitrin and myricetin were evaluated for their abilities to modulate the production of NO, TNF-α and IL-10 in LPS/IFN-γ stimulated J774.A1 macrophages. RESULTS: It was found that orally administrated AE and Aq (125 and 250 mg/kg) inhibited carrageenan-induced paw oedema in mice. AE (125 and 250 mg/kg) and Aq (125 mg/kg) reduced the time to licking at the second phase of the formalin method in vivo in mice. AE (250 mg/kg) and Aq (125 mg/kg) also reduced the number of writhes. AE, myricitrin and myricetin inhibited NO (320 µg/mL and 6.25-100 µM, respectively) and TNF-α production by macrophages (320 µg/mL for AE, 100 µM for myricitrin and 25-100 µM for myricetin). AE (160 and 320 µg/mL), myricitrin (50 and 100 µM) and myricetin (25-100 µM) increased IL-10 production by macrophages. CONCLUSIONS: The ethyl acetate and aqueous extracts from Campomanesia adamantium showed antinociceptive and anti-inflammatory effects supporting the use of the plant in folk medicine. The results suggest that anti-oedematogenic effect promoted by aqueous extract involves several anti-inflammatory mechanisms of action. The antinociceptive effect shown by aqueous extract can be due to the modulation of release of inflammatory mediators involved in nociception. The anti-inflammatory effects of AE and of its isolated flavonols may be attributed to inhibition of pro-inflammatory cytokines production, TNF-α and NO and to the increased of IL-10 production.


Asunto(s)
Analgésicos/uso terapéutico , Antiinflamatorios/uso terapéutico , Edema/tratamiento farmacológico , Myrtaceae/química , Dolor/tratamiento farmacológico , Fitoterapia/métodos , Extractos Vegetales/uso terapéutico , Acetatos/química , Analgésicos/farmacología , Animales , Antiinflamatorios/farmacología , Carragenina , Supervivencia Celular/efectos de los fármacos , Edema/inducido químicamente , Interleucina-10/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Ratones , Óxido Nítrico/metabolismo , Dolor/inducido químicamente , Dimensión del Dolor/efectos de los fármacos , Dimensión del Dolor/métodos , Extractos Vegetales/farmacología , Hojas de la Planta/química , Factor de Necrosis Tumoral alfa/metabolismo , Agua/química
18.
Rev. bras. farmacogn ; 22(5): 1104-1110, Sept.-Oct. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-649659

RESUMEN

The species of the genus Lychnophora, Asteraceae, are popularly known as "arnica" and are native from Brazilian savana (Cerrado). They are widely used in Brazilian folk medicine as anti-inflammatory, to treat bruise, pain, rheumatism and for insect bites. For evaluation of acute toxicity, the ethanolic extract was given to albino female and male mice. In open-field test, the extract of Lychnophora trichocarpha (Spreng.) Spreng. (0.750 g/kg) induced a significant inhibition of the spontaneous locomotor activity and exploratory behavior of the animals were observed 1 and 4 h after administration. In traction test, the same dose reduced the muscular force 1 h after administration. The exploratory behavior reduced significantly in the group that received 0.50 g/kg, 1 and 4 h after administration of the extract. The animals that received the doses of 0.25, 0.50 and 0.75 g/kg did not show any change of blood biochemical parameters comparing to control group and showed some histopathological changes such as congestion and inflammation of kidney and liver. The dose of 1.5 g/kg caused the most serious signs of toxicity. Histopathological changes observed was hemorrhage in 62.5% and pulmonary congestion in 100% of the animals. Brain and liver congestion was found in 62.5% of the animals.

19.
J Ethnopharmacol ; 142(3): 845-50, 2012 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-22732730

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The ethanolic extract of Lychnophora trichocarpha Spreng. is used in Brazilian folk medicine to treat bruise, pain and inflammatory diseases. AIM OF THE STUDY: The present study aimed at investigating whether ethanolic extract of L. trichocarpha, its ethyl acetate fraction and its main bioactive compounds could be useful to treat gouty arthritis by countering hyperuricemia and inflammation. MATERIALS AND METHODS: L. trichocarpha ethanolic extract (LTE), ethyl acetate fraction from ethanolic extract (LTA) and isolated compounds were evaluated for urate-lowering activity and liver xanthine oxidase (XOD) inhibition in oxonate-induced hyperuricemic mice. Anti-inflammatory activity in monosodium urate crystal-induced paw oedema, an experimental model of gouty arthritis, was also investigated. RESULTS: Crude ethanolic extract and its ethyl acetate fraction showed significant urate-lowering effects. LTE was also able to significantly inhibit liver xantine oxidase (XOD) activity in vivo at the dose of 250mg/kg. Luteolin, apigenin, lupeol, lychnopholide and eremantholide C showed the anti-hyperuricemic activities among tested compounds. Apigenin also showed XOD inhibitory activity in vivo. Luteolin, lychnopholide, lupeol and eremantholide C, in turn, did not shown significant inhibitory activity towards this enzyme, indicating that this mechanism is not likely to be involved in urate-lowering effects of those compounds. LTE, LTA, lupeol, ß-sitosterol, lychnopholide, eremantholide, luteolin and apigenin were also found to inhibit monosodium urate crystals-induced paw oedema in mice. CONCLUSIONS: Ethanolic extract of Lychnophora trichocarpha and some of its bioactive compounds may be promising agents for the treatment of gouty arthritis since they possesses both anti-hiperuricemic and anti-inflammatory properties.


Asunto(s)
Antiinflamatorios/uso terapéutico , Artritis Gotosa/tratamiento farmacológico , Asteraceae , Flavonoides/uso terapéutico , Hiperuricemia/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Acetatos/química , Animales , Antiinflamatorios/análisis , Etanol/química , Flavonoides/análisis , Hiperuricemia/inducido químicamente , Hiperuricemia/metabolismo , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Hígado/efectos de los fármacos , Hígado/enzimología , Masculino , Ratones , Ácido Oxónico , Fitoterapia , Componentes Aéreos de las Plantas/química , Extractos Vegetales/química , Solventes/química , Ácido Úrico/sangre , Xantina Oxidasa/metabolismo
20.
Acta cir. bras ; 25(5): 460-461, Sept.-Oct. 2010. ilus, tab
Artículo en Inglés | LILACS | ID: lil-558735

RESUMEN

PURPOSE: To evaluate and characterize the wound healing process profile induced by allantoin incorporated in soft lotion oil/water emulsion using the planimetric and histological methods. METHODS: Female Wistar rats (n=60) were randomly assigned to 3 experimental groups: (C) control group-without treatment; (E) group treated with soft lotion O/W emulsion excipients; (EA) group treated with soft lotion O/W emulsion containing allantoin 5 percent. The emulsions either containing or not allantoin were topically administered for 14 days and the wound area was evaluated by planimetry and by qualitative and quantitative histological analysis of open wound model. RESULTS: The data which were obtained and analyzed innovate by demonstrating, qualitatively and quantitatively, by histological analysis, the profile of healing process induced by allantoin. The results suggest that the wound healing mechanism induced by allantoin occurs via the regulation of inflammatory response and stimulus to fibroblastic proliferation and extracellular matrix synthesis. CONCLUSION: This work show, for the first time, the histological wound healing profile induced by allantoin in rats and demonstrated that it is able to ameliorate and fasten the reestablishment of the normal skin.


OBJETIVO: Avaliar e caracterizar o perfil cicatricial induzido pela alantoína incorporada em uma emulsão óleo/água, sob os aspectos planimétrico e histológico. MÉTODOS: Ratos Wistar fêmeas (n=60) foram agrupados aleatoriamente em três grupos experimentais grupo controle - sem tratamento (C); grupo tratado com emulsão pura (E); grupo tratado com emulsão contendo 5 por cento de alantoína (EA). As emulsões contendo ou não alantoína foram administradas topicamente durante 14 dias e a área da ferida foi avaliada por planimetria e por análise histológica qualitativa e quantitativa em modelo de ferida aberta. RESULTADOS: Na análise planimétrica não foi observado diferenças significativas entre os grupos experimentais. Os resultados da análise histológica sugerem que o mecanismo de cicatrização induzido pela alantoína ocorre via controle da resposta inflamatória e estímulos à proliferação fibroblástica e síntese de matrix extracelular de maneira mais intensa e rapidamente em relação aos grupos controles. CONCLUSÃO: Este trabalho mostra pela primeira vez o perfil histológico de cicatrização induzido pela alantoína em ratos, demonstrando ser capaz de melhorar e acelerar o processo de reconstituição da pele.


Asunto(s)
Animales , Femenino , Ratas , Alantoína/farmacología , Fármacos Dermatológicos/farmacología , Cicatrización de Heridas/efectos de los fármacos , Análisis de Varianza , Emulsiones , Interpretación de Imagen Asistida por Computador , Modelos Animales , Distribución Aleatoria , Ratas Wistar , Cicatrización de Heridas/fisiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...