Does diabetes alter immunolocalization of galectin-1 and galectin-3 in the rat ovary? / ¿La diabetes altera la inmunolocalización de galectina-1 y galectina-3 en el ovario de rata?

Diabetes mellitus (DM), is a metabolic disease occurring via insulin secretion deficiency from the pancreas and/or an insufficiency of tissue response to insulin. The present study is intended to show of immunolocalizations of beta-galactose-binding proteins Galectin-1 and Galectin-3 in diabetic rat ovarium and their relationship with diabetes. In this study, 8 to 10-week-old, 250­300 g weighing 50 mature female rats were used, in order to establish diabetes mellitus in those animals, 60 mg/kg intravenous streptozotocin was injected to each animal. After death, diabetics and non-diabetics rats's routine tissue processing steps is done to rat ovarial tissues for immunohistochemical investigation. Strong expressions of Galectin-1 and Galectin-3 were observed in the ovarial germinal epithelium and vascular endothelial. While the strong intense expression of Galectin-1 was seen in the zona pellucida, Galectin-3 expression was strongest in the cytoplesmic regions of cells. Zona pellucida has 3 protein complexes (ZP1, ZP2 and ZP3) in rats and in humans and they have the capability of recognizing the carbonhydrate fields in tissues. The strong expression of galectins in those regions could be the result of carbonhydrate binding properties expression of Gal-3 in the cytoplasmic regions of growing follicles could suggest the idea that Gal-3 could have effects on follicle growth. In conclusion, beta galactose-binding proteins Gal-1 and Gal-3 had stronger immunolocalization in diabetic rat ovarium when compared to the controls. Diabetes could increase the Gal-1 and Gal-3 expressions in the ovarial tissue.

La diabetes mellitus (DM) es una enfermedad metabólica debido a una deficiencia en la secreción de insulina por parte del páncreas o por una insuficiente respuesta de los tejidos a la insulina. El objetivo fue demostrar la inmunolocalización de las proteínas de unión beta-galactosa Galectina-1 y Galectina-3 en los ovarios de ratas diabéticas y su relación con la diabetes. Fueron utilizadas 50 ratas hembras maduras entre 8­10 semanas de edad, con un peso de 250­300 g. Con el fin de desarrollar DM en los animales, se inyectó a cada uno 60 mg/kg de estreptozotocina vía intravenosa. Después de la eutanasia, se realizó el procesamiento de rutina de los tejidos de las ratas diabéticas y no diabéticas para evaluar los tejidos ováricosa través de inmunohistoquímica. Se observaron expresiones fuertes de la Galectina-1 y Galectina-3 en el epitelio germinal y epitelio endotelial vascular del ovario. Si bien la fuerte e intensa expresión de Galectina-1 se observó en la zona pelúcida, la Galectina-3 tuvo una expresión más fuerte en las regiones de las células citoplasmáticas. La zona pelúcida tiene 3 complejos de proteínas (ZP1, ZP2 y ZP3) en ratas y en seres humanos y tienen la capacidad de reconocer los campos de carbohidratos en los tejidos. La fuerte expresión de las galectinas de esas regiones podría ser el resultado de las propiedades de unión a carbonhidratos expresión de Gal-3 en las regiones citoplasmáticas de los folículos en crecimiento, pudiendo sugerir que Gal-3 podría tener efectos sobre el crecimiento del folículo. En conclusión, las proteínas de unión beta-galactosa Gal-1 y Gal-3 tienen una mayor inmunolocalización en los ovarios de ratas diabéticas, en comparación a los controles. La diabetes podría incrementar las expresiones de Gal-1 y Gal-3 en el tejido ovárico.

Regeneración axonal posterior a lesiones traumáticas de médula espinal: Papel crítico de galectina-1

Al producirse una lesión de médula espinal (LME), un sinnúmero de proteínas inhibidoras de la regeneración axonal ocupan el sitio de lesión en forma secuencial. La primer proteína en llegar al mismo se conoce como semaforina 3A (Sema3A), siendo además una de las más potentes por su acción de inhibir la regeneración axonal. A nivel mecanístico la unión de esta proteína al complejo-receptor neuronal neuropilin-1 (NRP-1)/PlexinA4 evita que se produzca regeneración axonal. En este trabajo de revisión se discutirá la acción de galectin-1 (Gal-1), una proteína endógena de unión a glicanos, que selectivamente se une al complejo-receptor NRP-1/PlexinA4 de las neuronas lesionadas a través de un mecanismo dependiente de interacciones lectina-glicano, interrumpiendo la señalización generada por Sema3A y permitiendo de esta manera la regeneración axonal y recuperación locomotora luego de producirse la LME. Mientras ambas formas de Gal-1 (monomérica y dimérica) contribuyen a la inactivación de la microglia, solo la forma dimérica de Gal-1 es capaz de unirse al complejo-receptor NRP-1/PlexinA4 y promover regeneración axonal. Por lo tanto, Gal-1 dimérica produce recuperación de las lesiones espinales interfiriendo en la señalización de Sema3A a través de la unión al complejo-receptor NRP-1/PlexinA4, sugiriendo el uso de esta lectina en su forma dimérica para el tratamiento de pacientes con LME.

When spinal cord injury (SCI) occurs, a great number of inhibitors of axonal regeneration consecutively invade the injured site. The first protein to reach the lesion is known as semaphorin 3A (Sema3A), which serves as a powerful inhibitor of axonal regeneration. Mechanistically binding of Sem3A to the neuronal receptor complex neuropilin-1 (NRP-1) / PlexinA4 prevents axonal regeneration. In this special article we review the effects of galectin-1 (Gal-1), an endogenous glycan-binding protein, abundantly present at inflammation and injury sites. Notably, Gal1 adheres selectively to the NRP-1/PlexinA4 receptor complex in injured neurons through glycan-dependent mechanisms, interrupts the Sema3A pathway and contributes to axonal regeneration and locomotor recovery after SCI. While both the monomeric and dimeric forms of Gal-1 contribute to ’switch-off’ classically-activated microglia, only dimeric Gal-1 binds to the NRP-1/PlexinA4 receptor complex and promotes axonal regeneration. Thus, dimeric Gal-1 promotes functional recovery of spinal lesions by interfering with inhibitory signals triggered by Sema3A adhering to the NRP-1/PlexinA4 complex, supporting the use of dimeric Gal-1 for the treatment of SCI patients.

Estudo proteômico da interação do Aspergillus fumigatus com células endoteliais da veia umbilical humana (HUVECs) / Proteomic study of the interaction of Aspergillus fumigatus with human umbilical vein endothelial cells (HUVECs)

O Aspergillus fumigatus é o principal agente etiológico da aspergilose invasiva, uma infecção fúngica oportunista que acomete, principalmente, pacientes de Unidades Hematológicas, como aqueles com neutropenia profunda e prolongada. Após a filamentação este fungo angioinvasivo é capaz de ativar e causar danos em células endoteliais de veia umbilical humana (HUVEC) que passam a expressar um fenótipo pró-trombótico. A ativação destas células, dependente de contato célulacélula, é mediada por TNF-α e caracterizada pela expressão de moléculas próinflamatórias, como citocinas, quimiocinas e moléculas de adesão. Recentemente, nosso grupo comparou a ativação endotelial de HUVECs desafiadas com cepas selvagens e uma cepa mutante para o gene UGM1. Nestes experimentos a cepa mutante Δugm1, que apresenta um fenótipo de maior produção de galactosaminogalactana (GAG) na parede celular, mostrou um fenótipo hiperadesivo e uma capacidade maior de ativar células endoteliais. Entretanto, os receptores e as vias de sinalização envolvidos nesta ativação permanecem desconhecidos. Assim, o objetivo deste trabalho foi verificar as proteínas envolvidas nestes processos através do estudo das proteínas diferencialmente expressas nas HUVECs após a interação com A. fumigatus, usando a técnica proteômica 2D-DIGE. Brevemente, as HUVECs foram infectadas com tubos germinativos da cepa selvagem (AF293) e da cepa Δugm1 de A. fumigatus. Em seguida, as proteínas foram marcadas com diferentes fluorocromos e separadas por eletroforese bidimensional. A análise quantitativa foi realizada utilizando o software DeCyder...

Aspergillus fumigatus is the main etiological agent of invasive aspergillosis, the main opportunistic fungal infection of Hematologial Unity’s patients, especially those with long-term neutropenia. Upon filamentation, this angioinvasive fungus can activate and damage the human umbilical vein endothelial cells (HUVEC), which in response switch to a pro-thrombotic phenotype. HUVEC activation is mediated by TNF-α once cell-cell contact occurs. This activation is characterized by the expression of pro-inflammatory molecules such cytokines, chemokines and adhesion molecules. Recently, our group performed the comparison of HUVEC activation upon interaction with a wild type and the UGM1 mutant strains of A. fumigatus. The Δugm1 strain, which presents an increased production of the cell wall galactosaminogalactan, showed a hyper adherent phenotype and an increased capability to cause endothelial cell stimulation and activation, when compared with the wild type strain. The receptors involved in the pathogen-host interaction or the signaling pathways after endothelial activation by A. fumigatus remain unknown. Thus, the aim of this study was to investigate the differentially expressed proteins in HUVECs upon interaction with A. fumigatus, using the 2D-DIGE proteomic approach. Briefly, HUVECs were challenged with germlings of A. fumigatus wild type Af293 and Δugm1 strains and then submitted to protein extraction. The total HUVEC protein extracts were labeled with different CyDyes and fractionated by 2D electrophoresis. Quantitative analysis to determine the differences in protein abundance amongst interacted cells vs. control endothelial cells was performed using the software DeCyder. Five differentially expressed proteins were identified by MS/MS including galectin-1 and annexin A2, both overexpressed after the interaction. These two proteins are described elsewhere to be associated with host-pathogen interaction...

Expressão dos genes que codificam as proteínas anexina-1 e galectina-1 nos pólipos rinossinusais e sua modulação pelo glicocorticoide / Expression of genes that encode the annexin-1 and galectin-1 proteins in nasal polyposis and their modulation by glucocorticoid

A fisiopatologia da polipose rinossinusal não é totalmente compreendida, apesar de várias hipóteses em relação ao seu processo inflamatório. OBJETIVOS: Estudo prospectivo da expressão dos genes das proteínas, anexina-1 e a galectina-1, que têm ação anti-inflamatória, e sua modulação pelo glicocorticoide. MATERIAL E MÉTODOS: Onze pacientes portadores de polipose rinossinusal tiveram biopsiados seus pólipos em dois momentos: na ausência de glicocorticoide sistêmico, e na sua presença. Nas duas amostras, foi avaliada a expressão desses genes e comparada com a expressão na mucosa nasal normal do meato médio. RESULTADOS: Verificou-se que a média de expressão dos genes que codifica a anexina-1 e galectina-1 estava predominantemente aumentada, independente do uso do glicocorticoide em relação à mucosa nasal controle. Entretanto, nos pólipos sem uso de corticoide, a média de expressão do gene da anexina-1 foi significativamente maior do que nos pólipos que estavam sob uso de glicocorticoide. Com relação à galectina-1 não houve diferença significativa entre as médias de expressão antes e após o uso de glicocorticoide sistêmico. CONCLUSÃO: Os genes apresentaram um aumento da expressão na mucosa nasal polipoide, independente do uso do glicocorticoide, porém a relação destes dois genes das proteínas anti-inflamatórias com o glicocorticoide não ocorreu da mesma maneira.

Rhinosinusal polyps physiopathology is not fully understand, despite numerous hypotheses regarding its inflammatory process. AIMS: a prospective study regarding the gene expression of proteins: anexin-1 and galectin-1, which has an anti-inflammatory action and is modulated by steroids. MATERIALS AND METHODS: eleven patients with rhinosinusal polyps suffered a biopsy of their polyps at two moments: in the absence of systemic steroids and during its use. In the two samples we assessed the expression of these genes and compared it to the normal nasal mucosa in the middle meatus. RESULTS: We noticed that the mean expression of the genes which code anexin-1 and galectin-1 was predominantly increased, regardless of the use of steroids in relation to the control nasal mucosa. Notwithstanding, in polyps without the use of steroids, the mean gene expression of anexin-1 was significantly higher than in the polyps which were under the use of steroids. Regarding galectin-1, there was no significant difference between the expression mean values before and after the use of systemic steroids. CONCLUSION: The genes present an expression increase in the polyp mucosa, regardless of the use of steroids; nonetheless, the relationship of these two genes of anti-inflammatory proteins with steroids did not happen the same way.