RESUMEN
The perineuronal net (PNN) is a well-described highly specialized extracellular matrix structure found in the central nervous system. Thus far, no reports of its presence or connection to pathological processes have been described in the peripheral nervous system. Our study demonstrates the presence of a PNN in the spinal afferent innervation of the distal colon of mice and characterizes structural and morphological alterations induced in an ulcerative colitis (UC) model. C57Bl/6 mice were given 3% dextran sulfate sodium (DSS) to induce acute or chronic UC. L6/S1 dorsal root ganglia (DRG) were collected. PNNs were labeled using fluorescein-conjugated Wisteria Floribunda (WFA) l lectin, and calcitonin gene-related peptide (CGRP) immunofluorescence was used to detect DRG neurons. Most DRG cell bodies and their extensions toward peripheral nerves were found surrounded by the PNN-like structure (WFA+), labeling neurons' cytoplasm and the pericellular surfaces. The amount of WFA+ neuronal cell bodies was increased in both acute and chronic UC, and the PNN-like structure around cell bodies was thicker in UC groups. In conclusion, a PNN-like structure around DRG neuronal cell bodies was described and found modulated by UC, as changes in quantity, morphology, and expression profile of the PNN were detected, suggesting a potential role in sensory neuron peripheral sensitization, possibly modulating the pain profile of ulcerative colitis.
Asunto(s)
Colitis Ulcerosa , Colon , Ganglios Espinales , Ratones Endogámicos C57BL , Animales , Colitis Ulcerosa/patología , Colitis Ulcerosa/metabolismo , Ratones , Ganglios Espinales/patología , Ganglios Espinales/metabolismo , Colon/inervación , Colon/patología , Colon/metabolismo , Masculino , Péptido Relacionado con Gen de Calcitonina/metabolismo , Matriz Extracelular/patología , Matriz Extracelular/metabolismo , Sulfato de Dextran/toxicidad , Red Nerviosa/patología , Red Nerviosa/metabolismoRESUMEN
Malathion is an insecticide that is used to control arboviruses and agricultural pests. Adolescents that are exposed to this insecticide are the most vulnerable as they are in the critical period of postnatal sexual development. This study aimed to evaluate whether malathion damage can affect sperm function and its respective mechanisms when adolescents are exposed during postnatal sexual development. Twenty-four male Wistar rats (PND 25) were divided into three experimental groups and treated daily for 40 d: control group (saline 0.9%), 10 mg/kg (M10 group), or 50 mg/kg (M50 group) of malathion. At PND 65, the rats were anesthetized and euthanized. Testicles were collected for the evaluation of gene expression. Sperm cells from the epididymis were used for evaluation of the oxidative profile or spermatic function. Data showed that a lower dose of malathion downregulated the gene expression of androgen receptors and testosterone converter enzyme 17-ß-HSD in the testis. The acrosomal integrity of sperm cells was compromised in the M50 group, but not the M10 group. The mitochondrial activity was not impaired by exposure. Finally, although no alterations in malondialdehyde and glutathione levels were observed, malathion, at both doses, increased antioxidant enzyme catalase activity and, at a higher dose, superoxide dismutase activity. The present study showed that low doses of malathion considered to be inoffensive are capable of impairing sperm quality and function through the downregulation of testicular genic expression of AR enzyme 17-ß-HSD and can damage the spermatic antioxidant profile during critical periods of development.
Asunto(s)
Insecticidas , Testículo , Animales , Masculino , Ratas , Antioxidantes , Expresión Génica , Insecticidas/toxicidad , Insecticidas/metabolismo , Malatión/toxicidad , Malatión/metabolismo , Ratas Wistar , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Semen/metabolismo , Espermatozoides , Testículo/metabolismo , 17-Hidroxiesteroide DeshidrogenasasRESUMEN
BACKGROUND: Candida tropicalis is an important human pathogen that can undergo multiple forms of phenotypic switching. AIM: We aimed to evaluate the effect of phenotypic switching on the adhesion ability of C. tropicalis. METHODS: C. tropicalis morphotypes included parental phenotypes (clinical isolates) and switch phenotypes (crepe, revertant of crepe-CR, rough, revertant of rough-RR, irregular center and revertant of irregular center-ICR). Adhesion to polystyrene and HeLa cells was determined by crystal violet assay. The percentage of HeLa cells with adhered yeasts and the number of adhered yeasts per HeLa cell were determined by light microscopy. Filamentation among adhered cells was assessed by direct counting. RESULTS: On polystyrene, 60% of the switch strains showed difference (p < 0.05) on adhesion ability compared to their parental counterpart strains, and altered thickness of adhered cells layers. Filamentation was increased among adhered cells of the switched strains compared to parental strains. A positive correlation was observed between adhesion on polystyrene and filamentation for morphotypes of the system 49.07. The majority of the switched strains showed higher adhesion capability to HeLa cells in comparison to the adherence of the clinical strains. All revertant strains showed a higher number of yeast cells per HeLa cell compared to their variant counterparts (p < 0.05), with exception of the ICR. CONCLUSIONS: Our findings indicate that switching events in C. tropicalis affect adhesion and filamentation of adhered cells on polystyrene and HeLa cells. The rise of switch strains with increased adhesion ability may contribute to the success of infection associated with C. tropicalis.
Asunto(s)
Candida tropicalis , Poliestirenos , Biopelículas , Adhesión Celular , Células HeLa , Humanos , FenotipoRESUMEN
Paracoccidioidomycosis is a systemic mycosis prevalent in Latin American countries, caused by the dimorphic fungi Paracoccidioides brasiliensis and P. lutzii. The habitat of these fungi in nature remains undefined, although it is believed that infection occurs by inhalation of infective propagules present in soil. Sentinel animals, such as dogs, can be valuable epidemiological markers of paracoccidioidomycosis. Taking into account that paracoccidioidomycosis and visceral leishmaniasis may occur in the same area, the objective of this study was to evaluate the occurrence of P. brasiliensis infection in dogs positive for Leishmania sp. Serum samples of dogs positive (n = 199) and negative (n = 101) for Leishmania sp. were analyzed by the immunodiffusion test using P. brasiliensis exoantigen, and 22 samples (7.3%) were positive. The serum samples positive in the immunodiffusion test were also analyzed by Western blotting using the P. brasiliensis gp43 recombinant protein, and 86% of the samples were positive. A high positive correlation (r = 0.96) between positivity for Leishmania sp. and P. brasiliensis was observed. These data suggest an association between leishmaniasis and paracoccidioidomycosis in dogs.