RESUMEN
Introduction: Pathogenesis of cutaneous leishmaniases involves parasite growth, persistent inflammation, and likely participation of lipoproteins (LP). The cholesteryl ester transfer protein (CETP), involved in LP remodeling, has been shown to participate in the inflammatory response and the evolution of infectious conditions. Methods: We evaluated the impact of the presence of CETP on infection by Leishmania (L.) amazonensis in an experimental model of cutaneous leishmaniasis using C57BL6/J mice transgenic for human CETP (CETP), having as control their littermates that do not express the protein, wild-type (WT) mice. The progression of the lesion after infection in the footpad was monitored for 12 weeks. Two groups of animals were formed to collect the plantar pad in the 4th and 12th week post-infection. Results: The lesion increased from the 3rd week onwards, in both groups, with a gradual decrease from the 10th week onwards in the CETP group compared to the WT group, showing a reduction in parasitism and an improvement in the healing process, a reduction in CD68+ cells, and an increase in CD163+ and CD206, characterizing a population of M2 macrophages. A reduction in ARG1+ cells and an increase in INOS+ cells were observed. During infection, the LP profile showed an increase in triglycerides in the VLDL fraction in the CETP group at 12 weeks. Gene expression revealed a decrease in the CD36 receptor in the CETP group at 12 weeks, correlating with healing and parasite reduction. In vitro, macrophages derived from bone marrow cells from CETP mice showed lower parasite load at 48 h and, a reduction in arginase activity at 4 h accompanied by increased NO production at 4 and 24 h compared to WT macrophages, corroborating the in vivo findings. Discussion: The data indicate that the presence of CETP plays an important role in resolving Leishmania (L.) amazonensis infection, reducing parasitism, and modulating the inflammatory response in controlling infection and tissue repair.
Asunto(s)
Proteínas de Transferencia de Ésteres de Colesterol , Leishmaniasis Cutánea , Macrófagos , Ratones Endogámicos C57BL , Ratones Transgénicos , Animales , Proteínas de Transferencia de Ésteres de Colesterol/genética , Proteínas de Transferencia de Ésteres de Colesterol/metabolismo , Leishmaniasis Cutánea/inmunología , Leishmaniasis Cutánea/parasitología , Leishmaniasis Cutánea/metabolismo , Ratones , Macrófagos/inmunología , Macrófagos/metabolismo , Macrófagos/parasitología , Humanos , Progresión de la Enfermedad , Modelos Animales de EnfermedadRESUMEN
BACKGROUND: Chagas disease, endemic in Latin America and spreading globally due to emigration, has a significant health burden, particularly in relation to chagasic heart failure (HF). Chagasic cardiomyopathy (CCM) is characterized by chronic inflammatory myocardial disease. This study aimed to identify inflammatory parameters and biomarkers that could aid in the management of patients with chagasic HF. METHODS AND FINDINGS: A cohort study was conducted at a tertiary cardiology single-center over a mean follow-up period of 2.4 years. The study included patients with HF secondary to CCM enrolled between October 2013 and July 2017. Various clinical parameters, echocardiography findings, parasitemia status, brain natriuretic peptide (BNP) and troponin T (TnT) levels, and inflammatory biomarkers (IL-6, IL-10, IL-12p70, IL-17A, adiponectin, and IFN-γ) were assessed. The study encompassed a cohort of 103 patients, with a median age of 53 years and 70% being male. The left ventricular ejection fraction (LVEF) was 28%, with 40% of patients classified as NYHA II functional class. The median BNP level was 291 pg/ml. The observed mortality rate during the study period was 38.8%. Predictors of lower survival were identified as elevated levels of BNP, TnT, reduced LVEF, and increased adiponectin (thresholds: BNP > 309 pg/ml, TnT > 27.5 ng/ml, LVEF < 25.5%, adiponectin > 38 µg/mL). Notably, there was no evidence indicating a relationship between parasitemia and the inflammatory parameters with lower survival in these patients, including INF-γ, IL-6, IL-10, IL12-(p70), and IL17a. CONCLUSION: Despite the presence of a chronic inflammatory process, the evaluated inflammatory biomarkers in this cohort were not predictive of survival in patients with chagasic HF with reduced ejection fraction (HFrEF). However, reduced LVEF, elevated BNP, adiponectin levels, and troponin T were identified as predictors of lower survival in these patients.
Asunto(s)
Cardiomiopatía Chagásica , Insuficiencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Femenino , Insuficiencia Cardíaca/epidemiología , Volumen Sistólico , Interleucina-10 , Función Ventricular Izquierda , Estudios de Cohortes , Troponina T , Adiponectina , Interleucina-6 , Parasitemia , Biomarcadores , Péptido Natriurético Encefálico , PronósticoRESUMEN
Tegumentary leishmaniasis encompasses a spectrum of clinical manifestations caused by the parasitic protozoa of the genus Leishmania. In Brazil, there are at least seven Leishmania species that are endemic and responsible for this set of clinical manifestations of the disease. Current treatment is limited to a restricted number of drugs that in general have several drawbacks including parenteral use, toxicity, and severe side effects. Amphotericin B is considered a second-line drug for tegumentary leishmaniasis in Brazil, while miltefosine was recently approved for clinical use in the treatment of this disease. In this study, we investigated the in vitro susceptibility of Leishmania strains representative of the species endemic to Brazil, as well as a panel of thirteen clinical isolates of tegumentary leishmaniasis, to both amphotericin B and miltefosine. A moderate variation in the susceptibility to both drugs was found, where the EC50 values varied from 11.43 to 52.67 µM for miltefosine and from 12.89 to 62.36 nM for amphotericin B in promastigotes, while for the intracellular amastigotes, values ranged from 1.08 to 9.60 µM and from 1.69 to 22.71 nM for miltefosine and amphotericin B respectively. Furthermore, the clinical isolates and strains of the subgenus Viannia were evaluated for the presence of Leishmania RNA virus 1 (LRV1), as this is an important factor associated with disease severity and treatment outcome. These findings provide a preclinical dataset of the activity of these drugs against the causative species of tegumentary leishmaniasis in Brazil.
Asunto(s)
Antiprotozoarios , Leishmania , Leishmaniasis Cutánea , Leishmaniasis , Humanos , Anfotericina B/farmacología , Anfotericina B/uso terapéutico , Brasil/epidemiología , Leishmaniasis/tratamiento farmacológico , Fosforilcolina/farmacología , Fosforilcolina/uso terapéutico , Antiprotozoarios/farmacología , Antiprotozoarios/uso terapéutico , Leishmaniasis Cutánea/tratamiento farmacológico , Leishmaniasis Cutánea/epidemiología , Leishmaniasis Cutánea/parasitologíaRESUMEN
The parasitic protozoa Leishmania (Leishmania) infantum is the etiological agent of human visceral leishmaniasis and canine leishmaniasis in South America, where Brazil is the most affected country. This zoonotic disease is transmitted by the bite of an infected phlebotomine sand fly and dogs constitute the main domestic reservoir of the parasite. In this study, we screened 2348 dogs of the municipality of Embu das Artes, Brazil, for antibodies against the parasite. Prevalence for canine leishmaniasis seropositivity was 2.81%, as assessed using a Dual-Path Platform rapid test for canine leishmaniasis. Twenty-five seropositive dogs were euthanized for parasite isolation and 14 isolates were successful obtained. Nucleotide sequencing of the internal transcribed spacer confirmed the isolates to be L. (L.) infantum, and very low sequence variability was observed among them. The in vitro susceptibility to miltefosine and paromomycin was assessed and moderate variation in paromomycin susceptibility was found among the isolates in the promastigote and intracellular amastigote stages. On the other hand, in vitro susceptibility to miltefosine of these isolates was homogenous, particularly in the amastigote stage (EC50 values from 0.69 to 2.07 µM). In addition, the miltefosine sensitivity locus was deleted in all the isolates, which does not corroborate the hypothesis that the absence of this locus is correlated with a low in vitro susceptibility. Our findings confirm that the municipality of Embu das Artes is endemic for canine leishmaniasis and that isolates from this region are susceptible to paromomycin and miltefosine, indicating the potential of these drugs to be clinically evaluated in the treatment of human visceral leishmaniasis in Brazil.
Asunto(s)
Enfermedades de los Perros , Leishmania infantum , Leishmaniasis Visceral , Animales , Brasil/epidemiología , Enfermedades de los Perros/parasitología , Perros , Humanos , Leishmaniasis Visceral/tratamiento farmacológico , Leishmaniasis Visceral/epidemiología , Leishmaniasis Visceral/veterinaria , Paromomicina/uso terapéuticoRESUMEN
Leishmaniasis, a neglected tropical disease, is prevalent in 98 countries with the occurrence of 1.3 million new cases annually. The conventional therapy for visceral leishmaniasis requires hospitalization due to the severe adverse effects of the drugs, which are administered parenterally. Buparvaquone (BPQ) showed in vitro activity against leishmania parasites; nevertheless, it has failed in vivo tests due to its low aqueous solubility. Though, lipid nanoparticles can overcome this holdback. In this study we tested the hypothesis whether BPQ-NLC shows in vivo activity against L. infantum. Two optimized formulations were prepared (V1: 173.9 ± 1.6 nm, 0.5 mg of BPQ/mL; V2: 232.4 ± 1.6 nm, 1.3 mg of BPQ/mL), both showed increased solubility up to 73.00-fold, and dissolution up to 83.29%, while for the free drug it was only 2.89%. Cytotoxicity test showed their biocompatibility (CC50 >554.4 µM). Besides, the V1 dose of 0.3 mg/kg/day for 10 days reduced the parasite burden in 83.4% ±18.2% (p <0.05) in the liver. BPQ-NLC showed similar leishmanicidal activity compared to miltefosine. Therefore, BPQ-NLC is a promising addition to the limited therapeutic arsenal suitable for leishmaniasis oral administration treatment.
Asunto(s)
Antiprotozoarios , Leishmania infantum , Administración Oral , Antiprotozoarios/uso terapéutico , Lípidos , Liposomas , Nanopartículas , NaftoquinonasRESUMEN
A 31-year-old male patient developed an ulcer on the glans penis that evolved for three months without healing. We diagnosed it as leishmaniasis using polymerase chain reaction. No immunosuppression or associated diseases were observed. The patient was treated with meglumine antimoniate that cured the lesion in a month post-treatment. Here, we report this case of cutaneous leishmaniasis lesion at the unusual location of glans penis in an immunocompetent individual. The lesion likely developed due to the bite of a vector, highlighting the need for considering cutaneous leishmaniasis among differential diagnosis of sexually transmitted diseases in areas endemic for leishmaniasis.
Asunto(s)
Antiprotozoarios , Leishmaniasis Cutánea , Compuestos Organometálicos , Adulto , Antiprotozoarios/uso terapéutico , Brasil , Genitales , Humanos , Leishmaniasis Cutánea/diagnóstico , Leishmaniasis Cutánea/tratamiento farmacológico , Masculino , Meglumina/uso terapéutico , Antimoniato de Meglumina/uso terapéutico , Compuestos Organometálicos/uso terapéutico , Reacción en Cadena de la PolimerasaRESUMEN
Treatment of tegumentary leishmaniasis in Brazil is limited to pentavalent antimonial, amphotericin B and pentamidine. These drugs, administered parenterally, cause several side effects and have a varied clinical response, depending on the species of Leishmania. Urgent expansion of the therapeutic arsenal against the disease is therefore necessary. Paromomycin is an aminoglycoside antibiotic that has already been approved for the treatment of visceral leishmaniasis in Southeast Asia. Here, we provide an in vitro evaluation of the activity of paromomycin in fifteen clinical isolates from patients with tegumentary leishmaniasis at a reference center for the treatment of the disease. Furthermore, the in vitro susceptibility to this drug in reference strains of Leishmania species that are endemic in Brazil has also been evaluated. Among the clinical isolates, nine were typed as Leishmania (Viannia) braziliensis, five as L. (Leishmania) amazonensis and one as L. (V.) guyanensis. Although never exposed to paromomycin, we found variable susceptibility among these isolates and reference strains in promastigotes and intracellular amastigotes, with the drug being more active in the amastigote form of the parasite. This study provides a preclinical dataset that is useful for the evaluation of paromomycin in the treatment of tegumentary leishmaniasis caused by species that are endemic in Brazil.
Asunto(s)
Antiprotozoarios/farmacología , Leishmania/efectos de los fármacos , Leishmaniasis Cutánea/parasitología , Paromomicina/farmacología , Animales , Humanos , Leishmaniasis Cutánea/tratamiento farmacológico , Ratones , Ratones Endogámicos BALB CRESUMEN
Quantification of parasites in the context of Chagas disease is required to monitor the treatment with benznidazole, disease-associated cardiomyopathies and graft rejection after heart transplantation. As parasitological exams lack sensitivity, Real Time Polymerase Chain Reaction (rt-PCR) has emerged to evaluate the parasite load in blood samples and cardiac biopsies. However, despite its higher sensitivity, rt-PCR does not provide information on the location and distribution of amastigote nests within infected tissues, the characterization of inflammatory infiltrates or changes to tissue architecture. On the contrary, a sensitive immunohistochemistry technique (IHC) could fill these gaps. In the present study, a quantitative IHC exam was standardized and validated by testing adipose and cardiac tissues of experimentally infected mice containing variable parasite load levels of T. cruzi assessed by a sensitive Sybr Green rt-PCR with kDNA primers. Tissues were divided into four groups according to the parasite load: group A- 100 parasites/50 ng of DNA; group B -10 parasites; group C - around 1 parasite and group D - less than 1 parasite/50 ng/DNA. IHC was able to detect T. cruzi in the four groups, even in group D tissues containing fractions of a single parasite/50 ng of DNA sample according to rt-PCR. In conclusion, a highly sensitivity and reliable quantitative immunohistochemistry technique was developed and is proposed to estimate the percentage of T. cruzi-infected tissue area in chagasic patients presenting with cardiomyopathies, as a complementary test to rt-PCR.
Asunto(s)
Cardiomiopatía Chagásica/patología , Corazón/parasitología , Inmunohistoquímica/métodos , Miocardio/patología , Carga de Parásitos/métodos , Trypanosoma cruzi/aislamiento & purificación , Animales , Biopsia/instrumentación , Ratones , Carga de Parásitos/instrumentación , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
Abstract A 31-year-old male patient developed an ulcer on the glans penis that evolved for three months without healing. We diagnosed it as leishmaniasis using polymerase chain reaction. No immunosuppression or associated diseases were observed. The patient was treated with meglumine antimoniate that cured the lesion in a month post-treatment. Here, we report this case of cutaneous leishmaniasis lesion at the unusual location of glans penis in an immunocompetent individual. The lesion likely developed due to the bite of a vector, highlighting the need for considering cutaneous leishmaniasis among differential diagnosis of sexually transmitted diseases in areas endemic for leishmaniasis.
Asunto(s)
Humanos , Masculino , Adulto , Compuestos Organometálicos/uso terapéutico , Leishmaniasis Cutánea/diagnóstico , Leishmaniasis Cutánea/tratamiento farmacológico , Antiprotozoarios/uso terapéutico , Brasil , Reacción en Cadena de la Polimerasa , Antimoniato de Meglumina/uso terapéutico , Genitales , Meglumina/uso terapéuticoRESUMEN
Background: Chagas disease caused by Trypanosoma cruzi (T. cruzi) affects approximately six million individuals worldwide. Clinical manifestations are expected to occur due to the parasite persistence and host immune response. Herein we investigated potential associations between IL1B, IL6, IL17A, or IL18 polymorphism profiles and cardiomyopathy or T. cruzi parasitemia, as well as the impact of HIV infection on cardiopathy. Methods: Two hundred twenty-six patients and 90 control individuals were analyzed. IL1B rs1143627 T>C, IL6 rs1800795 C>G, IL17A rs2275913 G>A, IL18 rs187238 C>G, and IL18 rs1946518 C>A SNVs were analyzed by real-time PCR and T. cruzi parasitemia by PCR. Results: Our data revealed association between a cytokine gene polymorphism and parasitemia never previously reported. The IL6 rs1800795 CG genotype lowered the risk of positive parasitemia (OR = 0.45, 95% CI 0.24-0.86, P = 0.015). Original findings included associations between IL17A rs2275913 AA and IL18 s1946518 AA genotypes with decreased risk of developing cardiomyopathy (OR = 0.27, 95% CI 0.07-0.97, P = 0.044; and OR = 0.35, 95% CI 0.14-0.87, P = 0.023, respectively). IL18 rs1946518 AA and IL1B rs1143627 TC were associated with reduced risk for cardiomyopathy severity, including NYHA (New York Heart Association) class ≥ 2 (OR = 0.21, 95% CI 0.06-0.68, P = 0.009; and OR = 0.48, 95% CI 0.24-0.95, P = 0.036, respectively) and LVEF (left ventricular ejection fraction) <45% for IL18 rs1946518 AA (OR = 0.22, 95% CI 0.05-0.89, P = 0.034). A novel, unexpected protective effect of HIV infection against development/progression of cardiomyopathy was identified, based on a lower risk of developing cardiopathy (OR = 0.48, 95% CI 0.23-0.96, P = 0.039), NYHA class ≥ 2 (OR = 0.15, 95% CI 0.06-0.39, P < 0.001), and LVEF < 45% (OR = 0.03, 95% CI 0.00-0.25, P = 0.001). Digestive involvement was negatively associated with NYHA ≥ 2 and LVEF < 45% (OR = 0.20, 95% CI 0.09-0.47, P < 0.001; and OR = 0.24, 95% CI 0.09-0.62, P = 0.004, respectively). Conclusions: Our data support a protective role of IL17A AA, IL18 AA, and IL1B TC genotypes against development/progression of cardiomyopathy and a modulatory effect of the IL6 CG genotype on the risk of parasitemia in Chagas disease. Notably, HIV infection was shown to protect against development/progression of cardiopathy, potentially associated with a synergistic effect of HIV and highly active antiretroviral therapy (HAART), attenuating a Th1-mediated response in the myocardium. This proposed hypothesis requires confirmation, however, in larger and more comprehensive future studies.
Asunto(s)
Enfermedad de Chagas , Genotipo , Interleucina-17 , Interleucina-18 , Interleucina-1beta , Interleucina-6 , Parasitemia , Polimorfismo Genético , Trypanosoma cruzi/inmunología , Adulto , Enfermedad de Chagas/genética , Enfermedad de Chagas/inmunología , Femenino , Humanos , Interleucina-17/genética , Interleucina-17/inmunología , Interleucina-18/genética , Interleucina-18/inmunología , Interleucina-1beta/genética , Interleucina-1beta/inmunología , Interleucina-6/genética , Interleucina-6/inmunología , Masculino , Persona de Mediana Edad , Parasitemia/genética , Parasitemia/inmunologíaRESUMEN
Paromomycin is an aminoglycoside antibiotic approved in 2006 for the treatment of visceral leishmaniasis caused by Leishmania donovani in Southeast Asia. Although this drug is not approved for the treatment of visceral and cutaneous leishmaniasis in Brazil, it is urgent and necessary to evaluate the potential of this drug as alternative for the treatment against species responsible for these clinical forms of the disease. In Brazil, Leishmania amazonensis is responsible for cutaneous and diffuse cutaneous leishmaniasis. The diffuse cutaneous form of the disease is difficult to treat and frequent relapses are reported, mainly when the treatment is interrupted. Here, we evaluated paromomycin susceptibility in vitro of a L. amazonensis clinical isolate from a patient with cutaneous leishmaniasis and the reference strain L. amazonensis M2269, as well as its in vivo efficacy in a murine experimental model. Although never exposed to paromomycin, a significant differential susceptibility between these two lines was found. Paromomycin was highly active in vitro against the clinical isolate in both forms of the parasite, while its activity against the reference strain was less active. In vivo studies in mice infected with each one of these lines demonstrated that paromomycin reduces lesion size and parasite burden and a direct correlation between the susceptibility in vitro and the effectiveness of this drug in vivo was found. Our findings indicate that paromomycin efficacy in vivo is dependent on intrinsic susceptibility of the parasite. Beyond that, this study contributes for the evaluation of the potential use of paromomycin in chemotherapy of cutaneous leishmaniasis in Brazil caused by L. amazonensis.
Asunto(s)
Antiprotozoarios , Leishmania mexicana , Paromomicina/farmacología , Animales , Antiprotozoarios/farmacología , Antiprotozoarios/uso terapéutico , Brasil , Humanos , Leishmania mexicana/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Resultado del TratamientoRESUMEN
Leishmaniasis occurs in the five continents and represents a serious public health challenge, but is still a neglected disease, and the current pharmacological weaponry is far from satisfactory. Triglyceride-rich nanoparticles mimicking chylomicrons (TGNP) behave metabolically like native chylomicrons when injected into the bloodstream. Previously we have shown that TGNP as vehicle to amphothericin B (AB) for treatment of fungi infection showed reduced renal toxicity and lower animal death rates compared to conventional AB. The aim of the current study was to test the tolerability and effectiveness of the TGNP-AB preparation in a murine model of Leishmania amazonensis infection. The in vitro assays determined the cytotoxicity of TGNP-AB, AB, and TGNP in macrophages and promastigote forms and the leishmanicidal activity in infected macrophages. The in vivo toxicity tests were performed in healthy mice with increasing doses of TGPN-AB and AB. Then, animals were treated with 2.5 mg/kg/day of AB, 17.5 mg/kg/day of TGNP-AB, or TGNP three times a week for 4 weeks. TGNP-AB formulation was less cytotoxic for macrophages than AB. TGNP-AB was more effective than AB against the promastigotes forms of the parasite and more effective in reducing the number of infected macrophages and the number of amastigotes forms per cell. TGNP-AB-treated animals showed lower hepatotoxicity. In addition, TGNP-AB group showed a marked reduction in lesion size on the paws and parasitic load. The TGNP-AB preparation attained excellent leishmanicidal activity with remarkable lower drug toxicity at very high doses that, due to the toxicity-buffering properties of the nanocarrier, become fully tolerable.
Asunto(s)
Anfotericina B/administración & dosificación , Antiprotozoarios/administración & dosificación , Quilomicrones/química , Leishmaniasis Cutánea/tratamiento farmacológico , Triglicéridos/química , Anfotericina B/química , Anfotericina B/farmacología , Animales , Antiprotozoarios/química , Antiprotozoarios/farmacología , Línea Celular , Modelos Animales de Enfermedad , Composición de Medicamentos , Femenino , Macrófagos/citología , Macrófagos/efectos de los fármacos , Macrófagos/parasitología , Ratones , Ratones Endogámicos BALB C , Imitación Molecular , Nanopartículas , Carga de ParásitosRESUMEN
Most treatments of leishmaniasis require hospitalization and present side effects or parasite resistance; innovations in drug formulation/reposition can overcome these barriers and must be pursued to increase therapeutic alternatives. Therefore, we tested polymyxin B (polB) potential to kill Leishmania amazonensis, adsorbed or not in PBCA nanoparticles (PBCAnp), which could augment polB internalization in infected macrophages. PBCAnps were fabricated by anionic polymerization and analyzed by Dynamic Light Scattering (size, ζ potential), Nanoparticle Tracking Analysis (size/concentration), vertical diffusion cell (release rate), drug incorporation (indirect method, protein determination) and in vitro cell viability. Nanoparticles coated with polB (PBCAnp-polB) presented an adequate size of 261.5 ± 25.9 nm, low PDI and ζ of 1.79 ± 0.17 mV (stable for 45 days, at least). The 50% drug release from PBCAnp-polB was 6-7 times slower than the free polB, which favors a prolonged and desired release profile. Concerning in vitro evaluations, polB alone reduced in vitro amastigote infection of macrophages (10 µg/mL) without complete parasite elimination, even at higher concentrations. This behavior limits its future application to adjuvant leishmanicidal therapy or antimicrobial coating of carriers. The nanocarrier PBCAnp also presented leishmanicidal effect and surpassed polB activity; however, no antimicrobial activity was detected. PolB maintained its activity against E. coli, Pseudomonas and Klebsiella, adding antimicrobial properties to the nanoparticles. Thus, this coated drug delivery system, described for the first time, demonstrated antileishmanial and antimicrobial properties. The bactericidal feature helps with concomitant prevention/treatment of secondary infections that worst ulcers induced by cutaneous L. amazonensis, ultimately ending in disfiguring or disabling lesions.
Asunto(s)
Antibacterianos/farmacología , Antiprotozoarios/farmacología , Sistemas de Liberación de Medicamentos/métodos , Leishmania/efectos de los fármacos , Polimixina B/farmacología , Antibacterianos/química , Antiprotozoarios/química , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/microbiología , Sistemas de Liberación de Medicamentos/instrumentación , Evaluación Preclínica de Medicamentos , Leishmania/crecimiento & desarrollo , Leishmaniasis/tratamiento farmacológico , Leishmaniasis/parasitología , Macrófagos/parasitología , Nanopartículas/química , Polimixina B/químicaRESUMEN
A study with transmission electron microscopy of mycoplasma-contaminated HeLa cells using five cell donors referred to as donors A, B, C, D and E, observations are herein presented. Experiments performed with cells from donors B, C and D, revealed the presence of Mycoplasma hyorhinis after PCR and sequencing experiments. Bacteria probably originated from a cytoplasm with compacted tiny granular particles replacing the normal cytosol territories, or from the contact with the cytoplasm through a clear semi-solid material. The compact granularity (CG) of the cytoplasm was crossed by stripes of smooth and rough endoplasmic reticulum cisternae. Among apparently normal mitochondria, it was noted, in variable proportions, mitochondria with crista-delimited lucent central regions that expand to and occupied the interior of a crista-less organelle, which can undergo fission. Other components of the scenarios of mycoplasma-induced cell demolition are villus-like structures with associated 80-200 nm vesicles and a clear, flexible semi-solid, process-sensitive substance that we named jam-like material. This material coated the cytoplasmic surface, its recesses, irregular protrusions and detached cytoplasmic fragments. It also cushioned forming bacteria. Cyst-like structures were often present in the cytoplasm. Cells, mainly apoptotic, exhibiting ample cytoplasmic sectors with characteristic net-like profile due to adjoined vacuoles, as well as ovoid or elongated profiles, consistently appeared in all cells from the last four cell donors. These cells were named "modified host cells" because bacteria arose in the vacuoles. The possibility that, in some samples, there was infection and/or coinfection of the host cell by another organism(s) cannot be ruled out.
Asunto(s)
Citosol/microbiología , Retículo Endoplásmico/microbiología , Células HeLa/microbiología , Mitocondrias/microbiología , Mycoplasma hyorhinis/aislamiento & purificación , Vacuolas/microbiología , Células Cultivadas , Citosol/patología , ADN Bacteriano , Retículo Endoplásmico/patología , Células HeLa/patología , Humanos , Microscopía Electrónica de Transmisión , Mitocondrias/patología , Reacción en Cadena de la Polimerasa , Estaurosporina/farmacología , Vacuolas/patologíaRESUMEN
Dextran-coated poly (n-butyl cyanoacrylate) nanoparticles (PBCA-NPs) were prepared and were evaluated for enhanced delivery of a promising anti-Leishmania drug candidate, hydroxymethylnitrofurazone (NFOH), to phagocytic cells. Currently available chemotherapy for leishmaniasis, such as pentavalent antimonials, presents low safety and efficacy. Furthermore, widespread drug resistance in leishmaniasis is rapidly emerging. To overcome these drawbacks, the use of nanosized delivery systems can reduce systemic drug toxicity and increase the drug concentration in infected macrophages, therefore improving treatment of leishmaniasis. PBCA-NPs containing NFOH (PBCA-NFOH-NPs) were prepared by an anionic emulsion polymerisation method. The z-average and polydispersity index (PDI) were determined by photon correlation spectroscopy, the zeta potential by microelectrophoresis and the entrapment efficiency by HPLC. Cytotoxicity was determined using macrophages from BALB/c mice. Efficacy tests were performed using Leishmania amazonensis promastigotes and amastigotes. The z-average of PBCA-NFOH-NPs was 151.5 ± 61.97 nm, with a PDI of 0.104 ± 0.01, a zeta potential of -10.1 ± 6.49 mV and an entrapment efficiency of 64.47 ± 0.43%. Efficacy in amastigotes revealed IC50 values of 0.33 µM and 31.2 µM for the nanostructured and free NFOH, respectively (95-fold increase). The cytotoxicity study indicated low toxicity of the PBCA-NFOH-NPs to macrophages. The selectivity index was 370.6, which is 49-fold higher than free NFOH (7.6). Such findings indicated that improved efficacy could be due to NP internalisation following site-specific drug delivery and reactivation of immune protective reactions by the NP components. Thus, PBCA-NFOH-NPs have the potential to significantly improve the treatment of leishmaniasis, with reduced systemic side effects.
Asunto(s)
Antiprotozoarios/metabolismo , Leishmania/efectos de los fármacos , Macrófagos/parasitología , Nanopartículas/metabolismo , Nitrofurazona/análogos & derivados , Animales , Supervivencia Celular/efectos de los fármacos , Concentración 50 Inhibidora , Macrófagos/fisiología , Ratones Endogámicos BALB C , Nanopartículas/toxicidad , Nitrofurazona/metabolismo , Pruebas de Sensibilidad ParasitariaAsunto(s)
Retículo Endoplásmico/ultraestructura , Aparato de Golgi/microbiología , Mycoplasma/fisiología , Membrana Celular/microbiología , Membrana Celular/ultraestructura , Retículo Endoplásmico/microbiología , Aparato de Golgi/ultraestructura , Células HeLa/microbiología , Células HeLa/ultraestructura , Interacciones Huésped-Parásitos/fisiología , Humanos , Microscopía Electrónica de Transmisión , Mycoplasma/ultraestructuraAsunto(s)
Humanos , Retículo Endoplásmico/ultraestructura , Aparato de Golgi/microbiología , Mycoplasma/fisiología , Membrana Celular/microbiología , Membrana Celular/ultraestructura , Retículo Endoplásmico/microbiología , Aparato de Golgi/ultraestructura , Células HeLa/microbiología , Células HeLa/ultraestructura , Interacciones Huésped-Parásitos/fisiología , Microscopía Electrónica de Transmisión , Mycoplasma/ultraestructuraRESUMEN
Toxocariasis is a globally distributed parasitic infection caused by the larval stage of Toxocara spp. The typical natural hosts of the parasite are dogs and cats, but humans can be infected by the larval stage of the parasite after ingesting embryonated eggs in soil or from contaminated hands or fomites. The migrating larvae are not adapted to complete their life cycle within accidental or paratenic hosts like humans and laboratory animals, respectively, but they are capable of invading viscera or other tissues where they may survive and induce disease. In order to characterize hamsters (Mesocricetus auratus) as a model for Toxocara canis infection, histopathological and immunohistochemistry procedures were used to detect pathological lesions and the distribution of toxocaral antigens in the liver, lungs, and kidneys of experimentally infected animals. We also attempted to characterize the immunological parameters of the inflammatory response and correlate them with the histopathological findings. In the kidney, a correlation between glomerular changes and antigen deposits was evaluated using immunoelectron microscopy. The hamster is an adequate model of experimental toxocariasis for short-term investigations and has a good immunological and pathological response to the infection. Lung and liver manifestations of toxocariasis in hamsters approximated those in humans and other experimental animal models. A mixed Th2 immunological response to T. canis infection was predominant. The hamster model displayed a progressive rise of anti-toxocaral antibodies with the formation of immune complexes. Circulating antigens, immunoglobulin, and complement deposits were detected in the kidney without the development of a definite immune complex nephropathy.
Asunto(s)
Toxocara/parasitología , Toxocariasis/patología , Toxocariasis/parasitología , Animales , Antígenos Helmínticos/análisis , Proteínas del Sistema Complemento/análisis , Cricetinae , Modelos Animales de Enfermedad , Inmunoglobulinas/análisis , Inmunohistoquímica , Riñón/inmunología , Riñón/parasitología , Riñón/patología , Larva/crecimiento & desarrollo , Estadios del Ciclo de Vida , Hígado/inmunología , Hígado/parasitología , Hígado/patología , Pulmón/inmunología , Pulmón/parasitología , Pulmón/patología , Mesocricetus , Microscopía Inmunoelectrónica , Toxocara/inmunología , Toxocariasis/inmunologíaRESUMEN
SUMMARY This study evaluated the applicability of kDNA-PCR as a prospective routine diagnosis method for American tegumentary leishmaniasis (ATL) in patients from the Instituto de Infectologia Emílio Ribas (IIER), a reference center for infectious diseases in São Paulo - SP, Brazil. The kDNA-PCR method detected Leishmania DNA in 87.5% (112/128) of the clinically suspected ATL patients, while the traditional methods demonstrated the following percentages of positivity: 62.8% (49/78) for the Montenegro skin test, 61.8% (47/76) for direct investigation, and 19.3% (22/114) for in vitro culture. The molecular method was able to confirm the disease in samples considered negative or inconclusive by traditional laboratory methods, contributing to the final clinical diagnosis and therapy of ATL in this hospital. Thus, we strongly recommend the inclusion of kDNA-PCR amplification as an alternative diagnostic method for ATL, suggesting a new algorithm routine to be followed to help the diagnosis and treatment of ATL in IIER. .
RESUMO Este estudo avaliou a aplicabilidade do kDNA-PCR como método de rotina para diagnóstico de leishmaniose tegumentar americana (ATL) no Instituto de Infectologia Emílio Ribas (IIER), São Paulo, SP, Brasil. O método kDNA-PCR detectou DNA de Leishmania em 87,5% (112/128) dos pacientes com suspeita de ter leishmaniose e, os métodos tradicionais apresentaram as seguintes porcentagens de positividade: 62,8% (49/78) para o teste de Montenegro, 61,8% (47/76) para a pesquisa direta e 19,3% (22/114) para cultura in vitro. O método molecular confirmou a doença em amostras negativas ou inconclusivas pelos métodos laboratoriais tradicionais e, mostrou-se capaz de auxiliar na identificação de infecções causadas pela espécie Leishmania (V.) braziliensis. Além disso, a revisão dos prontuários médicos confirmou a importância do método PCR-RFLP no diagnóstico final de ATL, prognóstico e escolha do tratamento. Assim, recomendamos a inclusão do PCR como método diagnóstico de ATL na rotina hospitalar, e sugerimos um fluxograma para solicitação de exames laboratoriais. .
Asunto(s)
Humanos , ADN de Cinetoplasto/genética , ADN Protozoario/análisis , Leishmania braziliensis/genética , Leishmaniasis Cutánea/diagnóstico , Reacción en Cadena de la Polimerasa , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Pruebas Cutáneas , Centros de Atención TerciariaRESUMEN
This study evaluated the applicability of kDNA-PCR as a prospective routine diagnosis method for American tegumentary leishmaniasis (ATL) in patients from the Instituto de Infectologia Emílio Ribas (IIER), a reference center for infectious diseases in São Paulo - SP, Brazil. The kDNA-PCR method detected Leishmania DNA in 87.5% (112/128) of the clinically suspected ATL patients, while the traditional methods demonstrated the following percentages of positivity: 62.8% (49/78) for the Montenegro skin test, 61.8% (47/76) for direct investigation, and 19.3% (22/114) for in vitro culture. The molecular method was able to confirm the disease in samples considered negative or inconclusive by traditional laboratory methods, contributing to the final clinical diagnosis and therapy of ATL in this hospital. Thus, we strongly recommend the inclusion of kDNA-PCR amplification as an alternative diagnostic method for ATL, suggesting a new algorithm routine to be followed to help the diagnosis and treatment of ATL in IIER.