RESUMEN
In the pursuit of novel antioxidant therapies for the prevention and treatment of neurodegenerative diseases, three new arylpiperazine derivatives (LQFM181, LQFM276, and LQFM277) were synthesized through a molecular hybridization approach involving piribedil and butylated hydroxytoluene lead compounds. To evaluate the antioxidant and neuroprotective activities of the arylpiperazine derivatives, we employed an integrated approach using both in vitro (SH-SY5Y cells) and in vivo (neurotoxicity induced by 3-nitropropionic acid in Swiss mice) models. In the in vitro tests, LQFM181 showed the most promising antioxidant activity at the neuronal membrane and cytoplasmic levels, and significant neuroprotective activity against the neurotoxicity induced by 3-nitropropionic acid. Hence, this compound was further subjected to in vivo evaluation, which demonstrated remarkable antioxidant capacity such as reduction of MDA and carbonyl protein levels, increased activities of succinate dehydrogenase, catalase, and superoxide dismutase. Interestingly, using the same in vivo model, LQFM181 also reduced locomotor behavior and memory dysfunction through its ability to decrease cholinesterase activity. Consequently, LQFM181 emerges as a promising candidate for further investigation into its neuroprotective potential, positioning it as a new therapeutic agent for neuroprotection.
Asunto(s)
Antioxidantes , Fármacos Neuroprotectores , Nitrocompuestos , Piperazinas , Propionatos , Animales , Propionatos/toxicidad , Nitrocompuestos/toxicidad , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/química , Ratones , Piperazinas/farmacología , Piperazinas/química , Humanos , Línea Celular Tumoral , Antioxidantes/farmacología , Masculino , Succinato Deshidrogenasa/metabolismo , Superóxido Dismutasa/metabolismo , Catalasa/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Malondialdehído/metabolismo , Estrés Oxidativo/efectos de los fármacosRESUMEN
Estrone (E1) produces remarkable vascular effects, including relaxation, modulation of proliferation, apoptosis and cell adhesion. This study investigated the role of estrogen receptors and endothelial signaling pathways in the vascular relaxation promoted by E1. Aortic rings from male Wistar rats (250-300â¯g) were contracted with phenylephrine and stimulated with graded concentrations of E1. The concentration-dependent relaxation induced by E1 was abolished after removal of the endothelium or incubation with the estrogen receptor antagonist ICI 182,780. G protein-coupled estrogen receptor antagonism did not alter the E1 effect. Pretreatment of endothelium-intact arteries with inhibitors of nitric oxide synthase, guanylyl cyclase, calmodulin (CaM) and PI3K reduced the E1-induced vasorelaxation. Incubation with inhibitors of the MEK/ERK1/2 or p38MAPK pathways did not alter the E1 vasorelaxation. Similarly, inhibition of cyclooxygenase or blockade of potassium channels did not change the E1 effect. Western blot analysis evidenced that E1 induces phosphorylation of eNOS, PI3K and Akt in rat aorta. Our data demonstrate that E1 induces aortic vascular relaxation through classic estrogen receptors activation on the endothelium. We also identify CaM and PI3K/Akt pathways as critical mediators of the NO-cGMP signaling activation by E1. These findings contribute to the notion that this estrogen regulates arterial function and represents another link, besides 17ß-estradiol (E2), between postmenopause and vascular dysfunction.
Asunto(s)
Aorta/efectos de los fármacos , GMP Cíclico/metabolismo , Estrona/farmacología , Fosfatidilinositol 3-Quinasa/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores de Estrógenos/efectos de los fármacos , Sistemas de Mensajero Secundario/efectos de los fármacos , Vasodilatación/efectos de los fármacos , Vasodilatadores/farmacología , Animales , Aorta/enzimología , Calmodulina/metabolismo , Relación Dosis-Respuesta a Droga , Activación Enzimática , Técnicas In Vitro , Masculino , Óxido Nítrico Sintasa de Tipo III/metabolismo , Fosforilación , Ratas Wistar , Receptores de Estrógenos/metabolismoRESUMEN
Acid phosphatases (ACPases) are produced by a variety of fungi and have gained attention due their biotechnological potential in industrial, diagnosis and bioremediation processes. These enzymes play a specific role in scavenging, mobilization and acquisition of phosphate, enhancing soil fertility and plant growth. In this study, a new ACPase from Trichoderma harzianum, named ACPase II, was purified and characterized as a glycoprotein belonging to the acid phosphatase family. ACPase II presents an optimum pH and temperature of 3.8 and 65 °C, respectively, and is stable at 55 °C for 120 min, retaining 60% of its activity. The enzyme did not require metal divalent ions, but was inhibited by inorganic phosphate and tungstate. Affinity for several phosphate substrates was observed, including phytate, which is the major component of phosphorus in plant foods. The inhibition of ACPase II by tungstate and phosphate at different pH values is consistent with the inability of the substrate to occupy its active site due to electrostatic contacts that promote conformational changes, as indicated by fluorescence spectroscopy. A higher affinity for tungstate rather than phosphate at pH 4.0 was observed, in accordance with its highest inhibitory effect. Results indicate considerable biotechnological potential of the ACPase II in soil environments.
Asunto(s)
Fosfatasa Ácida/biosíntesis , Biotecnología/métodos , Proteínas Fúngicas/biosíntesis , Trichoderma/enzimología , Fosfatasa Ácida/química , Proteínas Fúngicas/química , Glicosilación , Concentración de Iones de Hidrógeno , Microbiología Industrial/métodos , Fosfatos/química , Conformación Proteica , Espectrometría de Fluorescencia , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Electricidad Estática , Temperatura , Compuestos de Tungsteno/químicaRESUMEN
Sequencing of a large number of expressed sequence tags from Blastocladiella emersonii revealed the presence of ten distinct putative members of the 70 kDa-heat shock protein (Hsp70) family in this fungus. The amino acid sequence deduced from eight of these cDNAs showed significant similarity to members of the Saccharomyces cerevisiae Hsp70 family, and the remaining displayed high sequence homology with hsp70 gene products from other organisms. The hsp70-3 gene was the most highly expressed at normal temperatures and was poorly induced during heat shock. Except for hsp70-4 and hsp70-6, all other hsp70 genes were induced to different degrees upon exposure of B. emersonii cells to heat shock, with hsp70-1 gene presenting the highest transcript levels. Phylogenetic analysis of complete B. emersonii putative Hsp70 protein sequences indicated that Hsp70-1 and Hsp70-3 corresponded to cytosolic proteins, whereas Hsp70-7 and Hsp70-9 are probably localized in the endoplasmic reticulum and mitochondria, respectively.