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Aged and photoaged skin exhibit fine wrinkles that are signs of epidermal inflammation and degeneration. It has been shown that healthy elderly skin expresses amyloidogenic proteins, including α-Synuclein, which are known to oligomerize and trigger inflammation and neurodegeneration. However, little is known about their putative role in skin physiology and sensitivity. To unravel this possible role, we investigated the impact of oligomeric α-Synuclein (Oα-Syn) in 2D and 3D keratinocyte human models. Exogenous Oα-Syn caused degeneration of reconstructed human epidermis (RHE) by diminishing proliferation and thickness of the stratum basale. Oα-Syn also increased NF-kB nuclear translocation in keratinocytes and triggered inflammation in the RHE, by increasing expression of interleukin-1β and tumor necrosis factor-alpha, and the release of tumor necrosis factor-alpha in a time-dependent manner. Dexamethasone and an IL-1β inhibitor partially diminished RHE degeneration caused by Oα-Syn. These findings suggest that Oα-Syn induces epidermal inflammation and decreases keratinocyte proliferation, and therefore might contribute to epidermal degeneration observed in human skin aging. more...

Coronavirus disease 2019 (COVID-19) is caused by acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which can infect several organs and lead to loss of vital organ function, especially impacting respiratory capacity. Among the extrapulmonary manifestations of COVID-19 is myocardial injury, caused both directly and indirectly by SARS-CoV-2, and which is associated with a high risk of mortality. One of the hallmarks of severe COVID-19 is the "cytokine storm", at which point the immune system malfunctions, leading to possible organ failure and death. Cannabinoids are known to have anti-inflammatory properties by negatively modulating the release of pro-inflammatory cytokines. Herein, we investigated the effects of the cannabinoid agonist WIN 55,212-2 (WIN) on SARS-CoV-2-infected human iPSC-derived cardiomyocytes (hiPSC-CMs). Although WIN did not modulate angiotensin-converting enzyme II, nor reduced SARS-CoV-2 infection and replication in hiPSC-CMs at the conditions tested, it had anti-inflammatory and protective effects by reducing the levels of interleukins 6, 8,18 and tumor necrosis factor-alpha (TNF-) and lactate dehydrogenase (LDH) activity in these cells without causing hypertrophic cardiac damage. These findings suggest that cannabinoids should be further investigated as an alternative therapeutic tool for the treatment of COVID-19. HighlightsO_LIHuman iPSC-derived cardiomyocytes (hiPSC-CMs) express CB1 receptor. C_LIO_LIThe cannabinoid receptor agonist, WIN 55,212-2 (WIN), does not influence SARS-CoV-2 infection in hiPSC-CMs. C_LIO_LIWIN reduces inflammation and death in SARS-CoV-2-infected hiPSC-CMs. C_LI more...

Cell senescence may promote epidermal inflammation and degeneration, termed as inflammaging, which is accompanied by keratinocyte loss, resulting in fine lines of wrinkles. Recent findings showed that healthy elderly skin expresses age- and neuron-related amyloidogenic proteins, such as tau, β-Amyloid34, and α-synuclein (α-Syn), typically found in patients with neurodegenerative diseases. These proteins form toxic aggregates that trigger inflammatory signals. Herein, we investigated the impact of oligomeric α-Syn (Oα-Syn) on the neurosphere (NP) and the reconstructed human epidermis (RHE) 3D models. First, we found the expression of α-Syn, β-Amyloid, and amyloid precursor protein (APP) in the RHE. Second, we challenged the RHE and NP with Oα-Syn, which decreased RHE regeneration, measured by the percentage of cell proliferation and thickness of the stratum basale, but did not affect NP neurite outgrowth. Oα-Syn did not decrease the number of human neonatal epidermal keratinocytes (HEKn) but, as seen for the RHE, it also decreased the proliferation of HEKn. We confirmed that the oligomeric, and not the monomeric α-Syn species, accounted for the proliferation-decreasing effect. Oα-Syn also increased the NF-kB nuclear translocation in HEKn analyzed by nucleus/cytoplasm NF-κB fluorescence intensity. In addition, Oα-Syn triggered inflammation in the RHE, by increasing the mRNA levels of IL-1β and tumor necrosis factor-alpha (TNF-α), and the release of TNF-α in a time-dependent manner. These findings show that Oα-Syn does not affect neurite outgrowth but induces a decrease in keratinocyte proliferation along with epidermal inflammation. With our tridimensional models, we demonstrated that the neurodegenerative protein Oα-Syn also degenerates the epidermis, drawing attention to the need of target-based screening to prevent and treat the effects of skin aging. more...

Heart dysfunction, represented by conditions such as myocarditis and arrhythmia, has been reported in COVID-19 patients. Therapeutic strategies focused on the cardiovascular system, however, remain scarce. The Sigma-1 receptor (S1R) has been recently proposed as a therapeutic target because its inhibition reduces SARS-CoV-2 replication. To investigate the role of S1R in SARS-CoV-2 infection in the heart, we used human cardiomyocytes derived from induced pluripotent stem cells (hiPSC-CM) as an experimental model. Here we show that the S1R antagonist NE-100 decreases SARS-CoV-2 infection and viral replication in hiPSC-CMs. Also, NE-100 reduces cytokine release and cell death associated with infection. Because S1R is involved in cardiac physiology, we investigated the effects of NE-100 in cardiomyocyte morphology and function. We show that NE-100 compromises cytoskeleton integrity and reduces beating frequency, causing contractile impairment. These results show that targeting S1R to challenge SARS-CoV-2 infection may be a useful therapeutic strategy but its detrimental effects in vivo on cardiac function should not be ignored. more...

O óleo de Eucalyptus globulus, apresenta diversas propriedades farmacológicas. Dentre elas, destacam-se seus efeitos antissépticos, expectorantes, antifúngicos e antimicrobiano. Diante disto o presente trabalho teve o objetivo geral de avaliar a atividade do óleo de Eucalyptus globulus no controle de bactérias da cavidade oral e objetivos específicos de comparar o efeito o óleo de Eucalyptus globulus com efeito da clorexidina e determinar em quais cepas bacterianas o óleo de Eucalyptus globulus apresentava maior eficácia. A atividade antimicrobiana foi testada in vitro, em bactérias do grupo Escherichia coli (E. coli), Enterococcus faecalis (E. faecalis) e Staphylococcus aureus (S. aureus) pelo método de difusão em ágar com a técnica de poços. Os poços foram preenchidos com as soluções de clorexidina 0,12% e óleo de Eucalyptus globulus em concentrações de 100%, 50%, 25%, 10%, 1% e 0,1% com a finalidade de comparar o efeito antimicrobiano pela inibição do crescimento. Os testes aconteceram em triplicata e a análise estatística foi realizada através do teste T de Student. Os dados foram organizados em tabelas para a demonstração dos resultados obtidos. Considerou-se como significante valores de p more...

Produtos de fonte de naturais estão sendo estudado para preservar a saúde humana, inclusive para prevenir doenças orais, pelo fato de medicamentos industrializados poderem acarretar resistência bacteriana e efeitos adversos. A própolis vermelha uma substância resinosa e complexa, de origem natural produzida pelas abelhas, têm propriedades terapêuticas, como atividade antimicrobiana e anti-inflamatória. O objetivo deste trabalho foi verificar o efeito antibacteriano da própolis vermelha no controle de bactérias da cavidade oral e os objetivos específicos foram comparar o efeito da própolis com efeito da clorexidina e determinar em quais cepas bacterianas a própolis apresentava maior eficácia. Utilizou-se cepas de Escherichia coli (ATCC-25922), Enterococcus faecalis (ATCC-29212) e Staphylococcus aureus (ATCC-25923). A atividade antimicrobiana da própolis foi determinada pelo método de difusão em ágar com a técnica de poços. Os poços foram preenchidos com 40 µL das soluções de clorexidina 0,12% (controle positivo), própolis vermelha em concentrações de 12%, 6%, 3%, 1.2%, 0,12%, 0,012% e água destilada (controle negativo). Os testes aconteceram em triplicata e a análise estatística foi realizada através do teste T de Student. Os dados foram organizados em tabelas e gráficos para a demonstração dos resultados obtidos. Considerou-se como significantes valores de p more...

Induced pluripotent stem (iPS) cells differentiated into neural progenitor cells (NPCs) hold great potential as a tool for modeling brain disease. When coupled to high content screening (HCS), NPCs may become a powerful tool for drug discovery. One of the goals of the new Molecular Biology and Cell Reprogramming, headed by Dr. Stevens Rehen at the D'Or Institute for Research and Education, is to develop a high content screening (HCS) strategy to study human brain diseases through the use of iPS. As a starting point, the effects of psychoactive drugs were characterized in NPCs by using HCS. Thousands of cells and single mitochondria were analyzed individually by HCS software and submitted to several sequences of morphometric analyses and fluorescence quantification. Morphological and functional alterations in mitochondria, which can be linked to energetic metabolism failure, a key trigger to abnormal neuronal development, were also observed. I will discuss the impact of HCS technology applied to neural stem cells as an attractive platform to drug discovery, cytotoxicity assessment and disease modeling. Supported by: BNDES, CNPq, FINEP, CAPES and FAPERJ. more...

Strategies aimed at improving spinal cord regeneration after trauma are still challenging neurologists and neuroscientists throughout the world. Many cell-based therapies have been tested, with limited success in terms of functional outcome. In this study, we investigated the effects of human dental pulp cells (HDPCs) in a mouse model of compressive spinal cord injury (SCI). These cells present some advantages, such as the ease of the extraction process, and expression of trophic factors and embryonic markers from both ecto-mesenchymal and mesenchymal components. Young adult female C57/BL6 mice were subjected to laminectomy at T9 and compression of the spinal cord with a vascular clip for 1 min. The cells were transplanted 7 days or 28 days after the lesion, in order to compare the recovery when treatment is applied in a subacute or chronic phase. We performed quantitative analyses of white-matter preservation, trophic-factor expression and quantification, and ultrastructural and functional analysis. Our results for the HDPC-transplanted animals showed better white-matter preservation than the DMEM groups, higher levels of trophic-factor expression in the tissue, better tissue organization, and the presence of many axons being myelinated by either Schwann cells or oligodendrocytes, in addition to the presence of some healthy-appearing intact neurons with synapse contacts on their cell bodies. We also demonstrated that HDPCs were able to express some glial markers such as GFAP and S-100. The functional analysis also showed locomotor improvement in these animals. Based on these findings, we propose that HDPCs may be feasible candidates for therapeutic intervention after SCI and central nervous system disorders in humans. more...

BackgroundThe helminth Schistosoma mansoni parasite resides in mesenteric veins where fecundated female worms lay hundred of eggs daily. Some of the egg antigens are trapped in the liver and induce a vigorous granulomatous response. High Mobility Group Box 1 (HMGB1), a nuclear factor, can also be secreted and act as a cytokine. Schistosome HMGB1 (SmHMGB1) is secreted by the eggs and stimulate the production of key cytokines involved in the pathology of schistosomiasis. Thus, understanding the mechanism of SmHMGB1 release becomes mandatory. Here, we addressed the question of how the nuclear SmHMGB1 can reach the extracellular space.Principal findingsWe showed in vitro and in vivo that CK2 phosphorylation was involved in the nucleocytoplasmic shuttling of SmHMGB1. By site-directed mutagenesis we mapped the two serine residues of SmHMGB1 that were phosphorylated by CK2. By DNA bending and supercoiling assays we showed that CK2 phosphorylation of SmHMGB1 had no effect in the DNA binding activities of the protein. We showed by electron microscopy, as well as by cell transfection and fluorescence microscopy that SmHMGB1 was present in the nucleus and cytoplasm of adult schistosomes and mammalian cells. In addition, we showed that treatments of the cells with either a phosphatase or a CK2 inhibitor were able to enhance or block, respectively, the cellular traffic of SmHMGB1. Importantly, we showed by confocal microscopy and biochemically that SmHMGB1 is significantly secreted by S. mansoni eggs of infected animals and that SmHMGB1 that were localized in the periovular schistosomotic granuloma were phosphorylated.ConclusionsWe showed that secretion of SmHMGB1 is regulated by phosphorylation. Moreover, our results suggest that egg-secreted SmHMGB1 may represent a new egg antigen. Therefore, the identification of drugs that specifically target phosphorylation of SmHMGB1 might block its secretion and interfere with the pathogenesis of schistosomiasis. more...