RESUMEN
The cell wall is one of the most important structures of pathogenic fungi, enabling initial interaction with the host and consequent modulation of immunological responses. Over the years, some researchers have shown that cell wall components of Histoplasma capsulatum vary among fungal isolates, and one of the major differences is the presence or absence of α-(1,3)-glucan, classifying wild-type fungi as chemotypes II or I, respectively. The present work shows that an isolate of H. capsulatum chemotype I induced lower levels of interleukin (IL)-8 secretion by the lung epithelial cell line A549, when compared to chemotype II yeasts. Thus, we expected that the absence of α-glucan in spontaneous variant yeasts, which were isolated from chemotype II cultures, would modify IL-8 secretion by A549 cells, but surprisingly, these fungi promoted similar levels of IL-8 secretion as their wild-type counterpart. Furthermore, when using a specific inhibitor for Syk activation, we observed that this inhibitor reduced IL-8 levels in A549 cell cultures infected with wild type chemotype I fungi. This inhibitor failed to reduce this cytokine levels in A549 cell cultures infected with chemotype II and their spontaneous variant yeasts, which also do not present α-glucan on their surface. The importance of SFKs and PKC δ in this event was also analyzed. Our results show that different isolates of H. capsulatum modulate distinct cell signaling pathways to promote cytokine secretion in host epithelial cells, emphasizing the existence of various mechanisms for Histoplasma pathogenicity.
Asunto(s)
Células Epiteliales Alveolares/metabolismo , Histoplasma/metabolismo , Interleucina-8/metabolismo , Células A549 , Células Epiteliales Alveolares/microbiología , Pared Celular/metabolismo , Glucanos/metabolismo , Histoplasma/aislamiento & purificación , Interacciones Huésped-Patógeno , Humanos , Pulmón/patología , Proteína Quinasa C-delta/metabolismo , Transducción de Señal , Especificidad de la Especie , Quinasa Syk/metabolismo , Familia-src Quinasas/metabolismoRESUMEN
Pharmaceutical discharges into the aquatic ecosystem are of environmental concern and sewage treatment plants (STPs) have been pointed out as the major source of these compounds to coastal zones, where oceanic disposal of sewage occurs through submarine outfalls. Diclofenac (DCF) is one of the most frequently detected pharmaceuticals in water, but little is known about the effects on marine organisms. In this study, we employed a tiered approach involving the determination of environmental concentrations of DCF in marine water and the adverse biological effects for fertilization, embryo-larval development and biomarker responses of the mussel Perna perna. Results indicate that effects in fertilization rate and embryo-larval development were found in the order of mg·L-1. However, low concentrations of DCF (ng·L-1) significantly decreased the lysosomal membrane stability and COX activity, as well as triggered DNA damage, oxidative stress and changes in antioxidant defenses. Our results point to an environmental hazard at coastal ecosystems and suggest the need for improvements in the treatment of domestic wastewater aiming to reduce DCF concentrations, as well as regulation on current environmental legislation and monitoring of aquatic ecosystems.
Asunto(s)
Diclofenaco/toxicidad , Perna/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Organismos Acuáticos , Brasil , Diclofenaco/análisis , Ecotoxicología/métodos , Embrión no Mamífero , Femenino , Masculino , Estrés Oxidativo/efectos de los fármacos , Perna/embriología , Agua de Mar/análisis , Pruebas de Toxicidad Aguda , Contaminantes Químicos del Agua/análisisRESUMEN
BACKGROUND: Kallikreins play a pivotal role in establishing prostate cancer. RESULTS: In contrast to the classical Kunitz plant inhibitor SbTI, the recombinant kallikrein inhibitor (rBbKIm) led to prostate cancer cell death, whereas fibroblast viability was not affected. CONCLUSION: rBbKIm shows selective cytotoxic effect and angiogenesis inhibition against prostate cancer cells. SIGNIFICANCE: New actions of rBbKIm may contribute to understanding the mechanisms of prostate cancer. Prostate cancer is the most common type of cancer, and kallikreins play an important role in the establishment of this disease. rBbKIm is the recombinant Bauhinia bauhinioides kallikreins inhibitor that was modified to include the RGD/RGE motifs of the inhibitor BrTI from Bauhinia rufa. This work reports the effects of rBbKIm on DU145 and PC3 prostate cancer cell lines. rBbKIm inhibited the cell viability of DU145 and PC3 cells but did not affect the viability of fibroblasts. rBbKIm caused an arrest of the PC3 cell cycle at the G0/G1 and G2/M phases but did not affect the DU145 cell cycle, although rBbKIm triggers apoptosis and cytochrome c release into the cytosol of both cell types. The differences in caspase activation were observed because rBbKIm treatment promoted activation of caspase-3 in DU145 cells, whereas caspase-9 but not caspase-3 was activated in PC3 cells. Because angiogenesis is important to the development of a tumor, the effect of rBbKIm in this process was also analyzed, and an inhibition of 49% was observed in in vitro endothelial cell capillary-like tube network formation. In summary, we demonstrated that different properties of the protease inhibitor rBbKIm may be explored for investigating the androgen-independent prostate cancer cell lines PC3 and DU145.
Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Antineoplásicos Fitogénicos/farmacología , Supervivencia Celular/efectos de los fármacos , Calicreínas/antagonistas & inhibidores , Proteínas de Plantas/farmacología , Apoptosis/efectos de los fármacos , Señalización del Calcio , Caspasa 3 , Caspasa 9/metabolismo , Adhesión Celular/efectos de los fármacos , Puntos de Control del Ciclo Celular , Línea Celular Tumoral , Movimiento Celular , Citocromos c/metabolismo , Fibroblastos/efectos de los fármacos , Fibroblastos/fisiología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/fisiología , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Lipopolisacáridos/farmacología , Masculino , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Neoplasias de la Próstata , Proteínas Recombinantes/farmacología , Inhibidor de la Tripsina de Soja de Kunitz/farmacologíaRESUMEN
Para um melhor entendimento da importancia e do papel biológico dos glicoesfingolipídeos (GSLs) e suas relaçoes com as doenças causadas por diferentes fungos patogênicos, nós analisamos as estruturas moleculares de GSLs de diferentes fungos como: Paracoccidioides brasiliensis, Histoplasma capsulatum, Sporothrix schenckii, Candida albicans, Cryptococcus neoformans, Cryptococcus laurentii, Cryptococcus albidus and Aspergillus fumigatus. GSLs de fungos foram isolados e purificados por DEAE-Sephadex, HPLC e HPTLC preparativa. As estruturas foram elucidadas por espectroscopia por 1-D e 2-D NMR, ESIIMS-CID/MS e GC/MS. Foram descritas as estruturas de glicosilinositol fosforilceramidas (GIPCs) presentes nas formas de micélio e levedura de P. brasiliensis: Pb-1 (Galf(31->6(Manpa1-->3)Manpa1->21ns1->P-->1Cer) e Pb-2 (Manpa1->3Manpa1->21ns1->P->1Cer), 0 GIPC Pb-1 apresentou reatividade com todos os soros de pacientes com PCM testados, e esta reatividade é devida ao resíduo terminal de (3-Galf. Foram descritos também os GIPCs de S. schenckii, sendo que os GIPCs da forma de micélio descritos sao: Ss-M1 (Manpa1-->61ns1-->P-->1Cer), Ss-M2 (Manpa1--->3Manpa1->61ns1->P->1Cer), Ss-M3 (Manpa1->3(Galpp1->4)Manpa1->21ns1->P->1Cer), e das formas de levedura sao: Ss-Y1 (Manpa1-->3Manpa1 ->61ns1->P-->1 Cer), Ss-Y2 (Manpa1->3Manpa1->2/61ns1->P->1Cer) e Ss-Y6 (Manpa1->3Manpa1->6GIcNH2a1->21ns1->P->1Cer). Esta foi a primeira descriçao de glicoesfingolipídeos com os "cores" Manpa1-),61ns e GlcNH2a1->21ns. Foram caracterizados também monohexosil ceramidas (CMHs) de P. brasiliensis, H. capsulatum, A. fumigatus, A. niger, Cryptococcus spp, C. albicans e S. schenckii. Estudos estruturais de CMHs de P. brasiliensis e H. capsulatum mostraram a presença de altos níveis de insaturaçao (E)-03 nos ácidos graxo das formas de micélio, quando comparados com as...(au)