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Prolactin has been recognized as neuroprotective hormone against various types of neuronal damage. This study was aimed to determine if prolactin protects against streptozotocin injury. A series of experiments were performed to determine neuronal survival by counting total neurons in medial hippocampus cortex and cerebellum. Astrogliosis was determined by immunofluorescence assays using GFAP, and behavioral improvement by prolactin after neuronal damage was determined by open-field and light-dark box tests. Results demonstrated that prolactin induced significant neuronal survival in both the hippocampus and cortex, but not in the cerebellum. No increase in astrogliosis was identified, but a significant reduction in anxiety levels was observed. Overall data indicate that prolactin may protect against a complex form of cell damage including oxidant stress and metabolic disruption by streptozotocin. Prolactin may be helpful strategy in the treatment of neuronal damage in neurological diseases.
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Hipocampo , Neurônios , Fármacos Neuroprotetores , Prolactina , Estreptozocina , Animais , Prolactina/metabolismo , Masculino , Fármacos Neuroprotetores/farmacologia , Hipocampo/metabolismo , Hipocampo/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Ratos , Neuroproteção/fisiologia , Neuroproteção/efeitos dos fármacos , Ratos Sprague-Dawley , Gliose/metabolismo , Cerebelo/metabolismo , Cerebelo/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologiaRESUMO
Background: Periodontitis is a chronic infectious disease, characterized by an exacerbated inflammatory response and a progressive loss of the supporting tissues of the teeth. Porphyromonas gingivalis is a key etiologic agent in periodontitis. Cystatin C is an antimicrobial salivary peptide that inhibits the growth of P. gingivalis. This study aimed to evaluate the antimicrobial activity of this peptide and its effect on cytokine production, nitric oxide (NO) release, reactive oxygen species (ROS) production, and programmed cell death in human macrophages infected with P. gingivalis. Methods: Monocyte-derived macrophages generated from peripheral blood were infected with P. gingivalis (MOI 1:10) and stimulated with cystatin C (2.75 µg/ml) for 24 h. The intracellular localization of P. gingivalis and cystatin C was determined by immunofluorescence and transmission electron microscopy (TEM). The intracellular antimicrobial activity of cystatin C in macrophages was assessed by counting Colony Forming Units (CFU). ELISA assay was performed to assess inflammatory (TNFα, IL-1ß) and anti-inflammatory (IL-10) cytokines. The production of nitrites and ROS was analyzed by Griess reaction and incubation with 2',7'-dichlorodihydrofluorescein diacetate (H2DCFDA), respectively. Programmed cell death was assessed with the TUNEL assay, Annexin-V, and caspase activity was also determined. Results: Our results showed that cystatin C inhibits the extracellular growth of P. gingivalis. In addition, this peptide is internalized in the infected macrophage, decreases the intracellular bacterial load, and reduces the production of inflammatory cytokines and NO. Interestingly, peptide treatment increased ROS production and substantially decreased bacterial-induced macrophage apoptosis. Conclusions: Cystatin C has antimicrobial and immuno-regulatory activity in macrophages infected with P. gingivalis. These findings highlight the importance of understanding the properties of cystatin C for its possible therapeutic use against oral infections such as periodontitis.
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Cistatina C , Macrófagos , Óxido Nítrico , Porphyromonas gingivalis , Espécies Reativas de Oxigênio , Porphyromonas gingivalis/imunologia , Humanos , Macrófagos/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/microbiologia , Cistatina C/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Óxido Nítrico/metabolismo , Citocinas/metabolismo , Periodontite/microbiologia , Periodontite/imunologia , Periodontite/tratamento farmacológico , Periodontite/patologia , Apoptose/efeitos dos fármacosRESUMO
Introduction: Worldwide, breast cancer is the most important cancer in incidence and prevalence in women. Different risk factors interact to increase the probability of developing it. Biological agents such as helminth parasites, particularly their excretory/secretory antigens, may play a significant role in tumor development. Helminths and their antigens have been recognized as inducers or promoters of cancer due to their ability to regulate the host's immune response. Previously in our laboratory, we demonstrated that chronic infection by Toxocara canis increases the size of mammary tumors, affecting the systemic response to the parasite. However, the parasite does not invade the tumor, and we decided to study if the excretion/secretion of antigens from Toxocara canis (EST) can affect the progression of mammary tumors or the pathophysiology of cancer which is metastasis. Thus, this study aimed to determine whether excretion/secretion T. canis antigens, injected directly into the tumor, affect tumor growth and metastasis. Methods: We evaluated these parameters through the monitoring of the intra-tumoral immune response. Results: Mice injected intratumorally with EST did not show changes in the size and weight of the tumors; although the tumors showed an increased microvasculature, they did develop increased micro and macro-metastasis in the lung. The analysis of the immune tumor microenvironment revealed that EST antigens did not modulate the proportion of immune cells in the tumor, spleen, or peripheral lymph nodes. Macroscopic and microscopic analyses of the lungs showed increased metastasis in the EST-treated animals compared to controls, accompanied by an increase in VEGF systemic levels. Discussion: Thus, these findings showed that intra-tumoral injection of T. canis EST antigens promote lung metastasis through modulation of the tumor immune microenvironment.
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Neoplasias da Mama , Parasitos , Toxocara canis , Toxocaríase , Humanos , Feminino , Animais , Camundongos , Antígenos de Helmintos , Injeções Intralesionais , Pulmão , Microambiente TumoralRESUMO
Eosinophils are mainly associated with parasitic infections and allergic manifestations. They produce many biologically active substances that contribute to the destruction of pathogens through the degranulation of microbicidal components and inflammatory tissue effects. In leishmaniasis, eosinophils have been found within inflammatory infiltrate with protective immunity against the parasite. We analyzed the responses of eosinophils from patients with localized (LCL) and diffuse (DCL) cutaneous leishmaniasis, as well as from healthy subjects, when exposed to Leishmania mexicana. All DCL patients exhibited blood eosinophilia, along with elevated eosinophil counts in non-ulcerated nodules. In contrast, only LCL patients with prolonged disease progression showed eosinophils in their blood and cutaneous ulcers. Eosinophils from DCL patients secreted significantly higher levels of IL-6, IL-8, and IL-13, compared to eosinophils from LCL patients. Additionally, DCL patients displayed higher serum levels of anti-Leishmania IgG antibodies. We also demonstrated that eosinophils from both LCL and DCL patients responded to L. mexicana promastigotes with a robust oxidative burst, which was equally intense in both patient groups and significantly higher than in healthy subjects. Coincubation of eosinophils (from donors with eosinophilia) with L. mexicana promastigotes in vitro revealed various mechanisms of parasite damage associated with different patterns of granule exocytosis: 1) localized degranulation on the parasite surface, 2) the release of cytoplasmic membrane-bound "degranulation sacs" containing granules, 3) release of eosinophil extracellular traps containing DNA and granules with major basic protein. In conclusion, eosinophils damage L. mexicana parasites through the release of granules via diverse mechanisms. However, despite DCL patients having abundant eosinophils in their blood and tissues, their apparent inability to provide protection may be linked to the release of cytokines and chemokines that promote a Th2 immune response and disease progression in these patients.
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Eosinofilia , Leishmania mexicana , Leishmaniose Cutânea , Leishmaniose Tegumentar Difusa , Parasitos , Animais , Humanos , Eosinófilos , Progressão da DoençaRESUMO
The ascomycete Histoplasma capsulatum is the causative agent of systemic respiratory mycosis histoplasmosis, which sometimes develops acute disseminated or chronic clinical forms, with the latter usually associated with granuloma formation. The present report shows differential histopathological changes in the pulmonary inflammatory response of mice infected intranasally with the mycelial morphotype of H. capsulatum strains with distinct genotypes, EH-46 and G-217B, classified as LAm A2 and NAm 2 phylogenetic species, respectively. Infected male BALB/c mice were sacrificed at different postinfection times, and their serial lung sections were stained with periodic acid-Schiff and analyzed via microscopy. In mice infected with the LAm A2 strain, the results showed progressive changes in the inflammatory infiltrate of the lung parenchyma during the first hours and days postinfection as well as granulomas with macrophages containing intracellular yeast cells, which prevailed at 14 and 21 days postinfection. Bronchiolar-associated lymphoid tissue was induced in mice infected with both strains, primarily in mice infected with the NAm 2 strain. Several lung sections from mice infected with the LAm A2 strain showed PAS-positive yeast cells aggregated in a perinuclear crown-like arrangement in macrophages from 3 h to 21 days postinfection. These findings highlight differences in the host pulmonary inflammatory response associated with distinct H. capsulatum species.
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Essential oils (EOs) are complex mixtures of volatile natural compounds. We have extensively studied the EO of Bursera morelensis, which demonstrates antibacterial, antifungal, anti-inflammatory, and wound-healing activities. The objective of this work was to determine the effect of this EO on fibroblast migration in a three-dimensional in vitro model. For the three-dimensional in vitro model, a series of fibrin hydrogel scaffolds (FSs) were built in which fibroblasts were cultured and subsequently stimulated with fibroblast growth factor (FGF) or EO. The results demonstrated that these FSs are appropriate for fibroblast culture, since no decrease in cell viability or changes in cell proliferation were found. The results also showed that this EO promotes cell migration four hours after stimulation, and the formation of cell projections (filopodia) outside the SF was observed. From these results, we confirmed that part of the mechanism of action of the essential oil of B. morelensis during the healing process is the stimulation of fibroblast migration to the wound site.
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Bursera , Óleos Voláteis , Óleos Voláteis/farmacologia , Projetos de Pesquisa , Movimento Celular , Fatores de Crescimento de Fibroblastos , FibroblastosRESUMO
Ovine gammaherpesvirus 2 (OvHV-2), a member of the genus Macavirus, causes sheep-associated malignant catarrhal fever (SA-MCF), a fatal lymphoproliferative disease affecting a wide variety of ungulates in addition to horses. This study described an outbreak of SA-MCF in Mexico and the identification of the OvHV-2 virus in primary rabbit testis cultures through the generation of intranuclear inclusion bodies, syncytia, immunofluorescence (IF), immunocytochemistry (ICC), immunohistochemistry (IHC), endpoint polymerase chain reaction (PCR), and partial sequencing of the ORF75 gene. The animals involved in this outbreak showed mucogingival ulcers in the vestibule of the mouth and tongue, hypersalivation, corneal opacity, reduced food consumption, and weight loss of variable severity. These clinical signs and the histopathological findings suggested the diagnosis of SA-MCF. Buffy coat fractions from the anticoagulated blood samples of ill animals were collected and analyzed by PCR. Positive buffy coats were used to inoculate the primary cell cultures of rabbit testis to identify the virus. Small clusters of refractile cytomegalic cells, characteristic of viral cytopathic effects, were observed between 48 and 72 h post-infection. Furthermore, intranuclear acidophilic inclusion bodies (IBs) were identified in the inoculated primary culture cells, and the cytoplasm showed immunoreactivity with hyperimmune rabbit serum against OvHV-2. Moreover, in the liver histological sections from sick deer, immunoreactive juxtanuclear IBs were identified with the same rabbit hyperimmune serum. The obtained sequences were aligned with the OvHV-2 sequences reported in GenBank and revealed a nucleotide identity higher than 98%. Based on the evidence provided in this study, we conclude that the outbreak of SA-MCF in the municipality of Tequisquiapan in the state of Queretaro, Mexico, was caused by OvHV-2. This is the second study reporting that horses are susceptible to OvHV-2 infection and can develop SA-MCF. We identified for the first time in Mexico, the presence of OvHV-2 in buffy coats from horses and Artiodactyla.
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Artiodáctilos , Cervos , Gammaherpesvirinae , Febre Catarral Maligna , Animais , Bovinos , Masculino , Coelhos , Surtos de Doenças/veterinária , Gammaherpesvirinae/genética , Cavalos , Febre Catarral Maligna/epidemiologia , México/epidemiologia , OvinosRESUMO
Breast cancer is the leading malignancy in women worldwide, both in terms of incidence and mortality. Triple-negative breast cancer (TNBC) is the type with the worst clinical outcomes and with fewer therapeutic options than other types of breast cancer. GK-1 is a peptide that in the experimental model of the metastatic 4T1 breast cancer has demonstrated anti-tumor and anti-metastatic properties. Herein, GK-1 (5 mg/kg, i.v.) weekly administrated not only decreases tumor growth and the number of lung macro-metastases but also lung and lymph nodes micro-metastases. Histological analysis reveals that GK-1 reduced 57% of the intra-tumor vascular areas, diminished the leukemoid reaction's progression, and the spleens' weight and length. A significant reduction in VEGF-C, SDF-1, angiopoietin-2, and endothelin-1 angiogenic factors was induced. Moreover, GK-1 prevents T cell exhaustion in the tumor-infiltrating lymphocytes (TILs) decreasing PD-1 expression. It also increased IFN-γ and granzyme-B expression and the cytotoxic activity of CD8+ TILs cells against tumor cells. All these features were found to be associated with a better antitumor response and prognosis. Altogether, these results reinforce the potential of GK-1 to improve the clinical outcome of triple-negative breast cancer immunotherapy. Translation research is ongoing towards its evaluation in humans.
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Antineoplásicos , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Animais , Camundongos , Neoplasias de Mama Triplo Negativas/patologia , Exaustão das Células T , Linfócitos do Interstício Tumoral/metabolismo , Prognóstico , Antineoplásicos/uso terapêutico , Linfócitos T CD8-Positivos/metabolismoRESUMO
Histoplasmosis is one of the systemic mycoses that can involve the Central Nervous System (CNS), and it is caused by the dimorphic ascomycete species of the Histoplasma capsulatum complex. Once in the CNS, this pathogen causes life-threatening injuries that are associated with clinical manifestations of meningitis, focal lesions (abscesses, histoplasmomas), and spinal cord injuries. The present review provides updated data and highlights a particular vision regarding this mycosis and its causative agent, as well as its epidemiology, clinical forms, pathogenesis, diagnosis, and therapy, focusing on the CNS.
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BACKGROUND: Although the cavernous sinus (CS) has been studied since 1695, its anatomy and name are still under discussion. METHOD: Anatomy and histology of 40 CS from human cadavers were studied, included both from a newborn specimen. RESULTS: Two walls limit the CS, an inferior medial one composed only of the dura's outer layer and a superior lateral one consisting of both dura's layers. Sinusoidal veins pass through the lateral wall of the CS as a transition between venous tributaries and the CS. An endothelial layer covers the inner surface of the CS and the outer surface of the internal carotid artery. The space within the CS shows trabeculae, which are rarer in adults compared to the newborn. The loss of trabeculae in the CS may be a natural process along with life. CONCLUSIONS: In conclusion, the CS is a real sinus, and the term "cavernous sinus" is appropriately applied.
ANTECEDENTES: Si bien el seno cavernoso (SC) ha sido estudiado desde 1695, su anatomía y nombre aún están bajo discusión. MÉTODOS: Se estudiaron la anatomía y la histología de 40 SC de cadáveres humanos, incluyendo los dos de un recién nacido. RESULTADOS: El SC está limitado por dos paredes, una inferomedial compuesta solo por la capa más externa de la duramadre y otra superolateral compuesta por ambas capas de la duramadre. Hay venas sinusoidales que atraviesan la pared lateral del SC formando una transición entre venas tributarias y el SC. Una capa endotelial recubre la superficie interna del SC y la superficie externa de la arteria carótida interna. El espacio dentro del SC presenta trabéculas, las cuales son escasas en el adulto en comparación con el recién nacido. La pérdida de trabéculas en el SC puede ser un proceso natural a lo largo de la vida. CONCLUSIONES: En conclusión, el SC es un verdadero seno, por lo que el término «seno cavernoso¼ se aplica de forma correcta.