14 research outputs found
Recombinant Probiotics and Microbiota Modulation as a Good Therapy for Diseases Related to the GIT
Many diseases that affect the gastrointestinal tract (GIT) have great influence on the quality of life of the majority of patients. Many probiotic strains are being highly studied as a promising candidate due to their beneficial effect reported in the GIT. With the purpose of increasing the beneficial characteristics of some probiotics strains and, consequently, to improve further the reported results, many probiotic strains expressing or encoding different proteins, with anti-inflammatory activities, have been developed. These recombinant strains have been reported as good candidates for the treatment of different pathological conditions, especially colitis and mucositis disease since they have been shown to have positive results and good perspectives for GIT inflammation. Thus, this chapter will first address the aspects of the gastrointestinal tract in humans as well as its microbiota. In a second moment, it will discuss about chronic diseases, mainly the intestinal ones. Finally, it will discuss about probiotics, especially concerning on lactic acid bacteria (LAB), and its action in the prevention and treatment of these diseases. At the final part, we will point out aspects on the development of recombinant strains and the results found in the literature on disease models
Growth differentiation factor 11 delivered by dairy Lactococcus lactis strains modulates inflammation and prevents mucosal damage in a mice model of intestinal mucositis
Mucositis is an inflammation of the gastrointestinal mucosa that debilitate the quality of life of patients undergoing chemotherapy treatments. In this context, antineoplastic drugs, such as 5-fluorouracil, provokes ulcerations in the intestinal mucosa that lead to the secretion of pro-inflammatory cytokines by activating the NF-κB pathway. Alternative approaches to treat the disease using probiotic strains show promising results, and thereafter, treatments that target the site of inflammation could be further explored. Recently, studies reported that the protein GDF11 has an anti-inflammatory role in several diseases, including in vitro and in vivo results in different experimental models. Hence, this study evaluated the anti-inflammatory effect of GDF11 delivered by Lactococcus lactis strains NCDO2118 and MG1363 in a murine model of intestinal mucositis induced by 5-FU. Our results showed that mice treated with the recombinant lactococci strains presented improved histopathological scores of intestinal damage and a reduction of goblet cell degeneration in the mucosa. It was also observed a significant reduction of neutrophil infiltration in the tissue in comparison to positive control group. Moreover, we observed immunomodulation of inflammatory markers Nfkb1, Nlrp3, Tnf, and upregulation of Il10 in mRNA expression levels in groups treated with recombinant strains that help to partially explain the ameliorative effect in the mucosa. Therefore, the results found in this study suggest that the use of recombinant L. lactis (pExu:gdf11) could offer a potential gene therapy for intestinal mucositis induced by 5-FU
Updated cardiovascular prevention guideline of the Brazilian Society of Cardiology: 2019
Sem informação113478788
Avaliação in vitro da atividade antiviral da silimarina contra o Zika virus (Flaviviridae).
Programa de Pós-Graduação em Ciências Biológicas. Núcleo de Pesquisas em Ciências Biológicas, Pró-Reitoria de Pesquisa de Pós Graduação, Universidade Federal de Ouro Preto.O Zika virus (ZIKV) é um arbovírus pertencente à família Flaviviridae e ao gênero
Flavivirus. Em humanos, causa a febre Zika, uma doença com sintomas tais como febre,
mialgia e cefaleia. Ainda, a infecção pelo ZIKV é relacionada a casos de microcefalia e
síndrome de Guillain-Barré no Brasil. Até o momento, não há vacina licenciada e/ou
tratamento específico para a febre Zika, portanto, a busca por compostos com atividade
antiviral pode ser uma alternativa promissora para o tratamento da doença. Neste contexto,
existem muitos compostos naturais capazes de gerar benefícios saudáveis, e a silimarina, um
conjunto de flavonoides extraído da planta cardo de leite (Silybum marianum), se destaca
pelas suas propriedades antioxidante, hepatoprotetora e antiviral. Assim, o principal objetivo
desse trabalho foi avaliar a atividade antiviral in vitro da silimarina contra o ZIKV. A
citotoxicidade da silimarina e sua atividade antiviral contra o ZIKV foram testados em células
Vero, utilizando diferentes concentrações de silimarina e o ZIKV numa multiplicidade de
infecção (moi) de 1. A viabilidade celular e a atividade antiviral global foram avaliadas
através do teste de MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide). A
capacidade da silimarina em reduzir o número de cópias do genoma viral foi também avaliada
por qRT-PCR, bem como sua capacidade de inibir a formação das Unidades Formadoras de
Placa (UFP). Posteriormente foi avaliada a atividade da silimarina em etapas pré e pós
infecção e a capacidade de inativar a partícula viral e inibir as etapas de adsorção e
penetração. Para tal, a silimarina foi adicionada às células em diferentes tempos e etapas da
infecção viral e, após 24 horas, o sobrenadante foi coletado para determinar o título de vírus
por contagem das UFP. A silimarina apresentou CC50 (Concentração Citotóxica para 50% das
células) de 247μg/mL, CE50 (Concentração Efetiva para 50% das células) de 19,3μg/mL e IS
(Índice de Seletividade) de 12,8, apresentando melhor atividade antiviral na concentração de
100μg/mL. A silimarina reduziu a produção viral em todos os tempos em que foi adicionada,
sendo a maior redução observada quando foi feito um pré-tratamento das células, 2 horas
antes da infecção. Ainda, a silimarina apresentou efeito virucida e de inibição da penetração e
adsorção viral, reduzindo os títulos virais em cerca de duas unidades logarítmicas. Deste
modo, é possível concluir que a silimarina possui significante atividade antiviral in vitro
contra o ZIKV e, portanto, pode ser um forte candidato para ser utilizado no tratamento das
infecções humanas causadas por esse vírus.Zika virus (ZIKV) is an arbovirus belonging to the family Flaviviridae and to the genus
Flavivirus. In humans, it causes the Zika fever, a disease with symptoms such as fever,
myalgia and headache. Also, ZIKV infection is associated with cases of microcephaly and
Guillain-Barré syndrome in Brazil. To date, there is no vaccine and/or specific treatment for
the disease. In this context, there are many sets of biological compounds with healthy benefits
and silymarin, a set of flavonoids extracted from the thistle milk plant (Silybum marianum),
stands out for its well-known antioxidant, hepatoprotective and antiviral properties. Thus, the
main objective of this work was to evaluate the in vitro antiviral activity of silymarin against
ZIKV. The cytotoxicity of silymarin and its antiviral activity against ZIKV were tested on
Vero cells using different concentrations of silymarin and ZIKV at a multiplicity of infection
(moi) of 1. Cell viability and overall antiviral activity were assessed by the MTT test (3- (4,5-
Dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide). The ability of silymarin to reduce
the number of copies of the viral genome was also assessed by qRT-PCR, as well as its ability
to inhibit the formation of plaque forming units (PFU). Subsequently, the activity of silymarin
was evaluated in pre and post infection stages and the ability to inactivate the viral particle
and to inhibit the steps of adsorption and penetration. To this end, silymarin was added to the
cells at different times and stages of viral infection and, after 24 hours, the supernatant was
collected to determine the virus titer by counting the PFU. Silymarin presented CC50
(Cytotoxic Concentration for 50% of cells) of 247 μg / mL, EC50 (Effective Concentration for
50% of cells) of 19.3 μg/mL and IS (Index of Selectivity) of 12.8, showing better antiviral
activity at the concentration of 100μg/mL. Silymarin reduced viral production at all times
when it was added, the largest reduction being observed when cells were pre-treated, 2 hours
prior to infection. Furthermore, silymarin showed virucidal effect and inhibition of viral
penetration and adsorption, reducing viral load in about two log units. Thus, it is possible to
conclude that silymarin has significant antiviral activity in vitro against ZIKV and therefore
may be a strong candidate for use in the treatment of human infections caused by this virus
Estudo dos determinantes dos custos no atendimento dos pacientes com lesão medular decorrente de trauma raquimedular
Spinal cord injury (SCI) is the main etiology related to spinal cord injury in young men. Due to the complexity of health care for these patients and their complications, the costs involved in these cases are high. Objective: To evaluate the costs associated with hospital and outpatient care for patients with traumatic spinal cord injury at a university service. Methods: This study was based on the review of clinical information about spinal cord injury and its complications, as well as the search for monetary amounts related to inpatient and outpatient care of individuals with traumatic SCI in a university service in 2009. Results: There were 51 patients with spinal trauma, of which 14 had SCI (age= 38.9 ± 20.8 years; men: 86%). Costs were R304,433.77 with spinal cord injury, and were statistically associated to the length of stay, the number of clinical complications and surgical procedures. Rehabilitation accounted for 23% of costs for patients with SCI. Conclusion: The costs related to the care of patients with SCI are higher than those associated with spinal trauma without neurological damage. The number of clinical complications is directly correlated with the length of hospital stay and the costs of this care. Rehabilitation corresponds to a smaller part of the expenses in the care of patients with SCI.O trauma raquimedular (TRM) é a principal etiologia relacionada à lesão medular em homens jovens. Em decorrência da complexidade ao atendimento desses pacientes e às suas complicações, os custos envolvidos nesses casos são vultosos. Objetivo: Avaliar os custos associados ao atendimento hospitalar e ambulatorial dos pacientes com lesão medular traumática num serviço universitário. Métodos: Este estudo baseou-se na revisão de informações clínicas sobre a lesão medular e suas complicações, bem como a busca de valores relacionados ao atendimento no período hospitalar e ambulatorial de indivíduos com lesão medular traumática num serviço universitário em 2009. Resultados: Foram contabilizados 51 pacientes com trauma na coluna vertebral, dos quais 14 apresentaram TRM (idade= 38,9 ± 20,8; homens: 86%). Os custos do atendimento foram R304.433,77 com lesão medular. Os custos do atendimento estiveram relacionados com o tempo de internação, o número de intercorrências clínicas e procedimentos cirúrgicos. A reabilitação correspondeu a 23% dos custos dos pacientes com TRM. Conclusão: Os custos relacionados ao atendimento do paciente com TRM são maiores que aqueles associados ao trauma de coluna sem lesão neurológica. O número de complicações clínicas correlaciona-se diretamente ao tempo de internação e os custos desse atendimento. A reabilitação corresponde a menor parte das despesas no cuidado aos pacientes com TRM
Antiviral activity of silymarin against Mayaro virus and protective effect in virus-induced oxidative stress.
Mayaro virus (MAYV) is a neglected arbovirus belonging to the family Togaviridae. Its infection leads to Mayaro fever, with clinical manifestations such as fever, myalgia, headache, rash, arthralgia, vomiting, and diarrhea. The most prominent complaint from infected person is the long-lasting arthritis/arthralgia. The treatment for Mayaro fever is mainly symptom-based and there are no vaccines or antiviral drugs currently available, thus, natural products with anti-MAYV activity may provide a potential alternative. Recent evidences suggest that oxidative stress plays an important role in MAYV infection and compounds capable of modulating oxidative stress could represent a novel therapeutic approach in modulating MAYV-associated oxidative cellular damage. Silymarin is a complex extracted of Silybum marianum, or milk thistle, and its major active compound is silybin, which has a remarkable biological effect. Its antioxidant and antiviral effects, including its antiviral activity against the Chikungunya virus (CHIKV), prompted us to think whether silymarin could also reduce the replication of the MAYV and restore the pro-oxidant/antioxidant balance in the context of MAYV infection, leading to reduced cellular oxidative stress. We assessed the antiviral activity and protective effect of silymarin against oxidative stress in MAYV-infected HepG2 cells. Cytopathic effect inhibition, viral replication, and plaque reduction assays were used to determine the anti-MAYV activity of silymarin. Additionally, we determined whether silymarin could reduce MAYV-induced oxidative cell damage. Briefly, silymarin exhibited potent antiviral activity against MAYV and reduced MAYV-induced ROS formation and levels of malondialdehyde (MDA) and carbonyl protein, which are biomarkers of oxidative stress. In conclusion, the ability of silymarin to inhibit MAYV replication and attenuate MAYV-induce oxidative stress warrants further investigation of this compound as a novel therapeutic approach to Mayaro fever disease
Efects of a?ai on oxidative stress, ER stress, and infammationrelated parameters in mice with high fat diet-fed induced NAFLD.
Non-alcoholic fatty liver disease (NAFLD), the most predominant liver disease worldwide, is a progressive condition that encompasses a spectrum of disorders ranging from steatosis to steatohepatitis, and, ultimately, cirrhosis and hepatocellular carcinoma. Although the underlying mechanism is complex and multifactorial, several intracellular events leading to its progression have been identified, including oxidative stress, inflammation, mitochondrial dysfunction, apoptosis, and altered endoplasmic reticulum (ER) homeostasis. Phenolic compounds, such as those present in a?ai (Euterpe oleracea Mart.), are considered promising therapeutic agents due to their possible beneficial effects on the prevention and treatment of NAFLD. We tested in vitro effects of aqueous a?ai extract (AAE) in HepG2 cells and its influence on oxidative stress, endoplasmic reticulum stress, and inflammation in a murine model of high fat diet-induced NAFLD. In vitro AAE exhibited high antioxidant capacity, high potential to inhibit reactive oxygen species production, and no cytotoxicity. In vivo, AAE administration (3?g/kg) for six weeks attenuated liver damage (alanine aminotransferase levels), inflammatory process (number of inflammatory cells and serum TNF?), and oxidative stress, through the reduction of lipid peroxidation and carbonylation of proteins determined by OxyBlot and modulation of the antioxidant enzymes: glutathione reductase, SOD and catalase. No change was observed in collagen content indicating an absence of fibrosis, stress-related genes in RE, and protein expression of caspase-3, a marker of apoptosis. With these results, we provide evidence that a?ai exhibits hepatoprotective effects and may prevent the progression of liver damage related to NAFLD by targeting pathways involved in its progression
Mayaro virus induction of oxidative stress is associated with liver pathology in a non-lethal mouse model.
Mayaro virus (MAYV) causes Mayaro fever in humans, a self-limiting acute disease, with persistent arthralgia and arthritis. Although MAYV has a remerging potential, its pathogenic mechanisms remain unclear. Here, we characterized a model of MAYV infection in 3?4-week BALB/c mice. We investigated whether the liver acts as a site of viral replication and if the infection could cause histopathological alterations and an imbalance in redox homeostasis, culminating with oxidative stress. MAYV-infected mice revealed lower weight gain; however, the disease was self-resolving. High virus titre, neutralizing antibodies, and increased levels of aspartate and alanine aminotransferases were detected in the serum. Infectious viral particles were recovered in the liver of infected animals and the histological examination of liver tissues revealed significant increase in the inflammatory infiltrate. MAYV induced significant oxidative stress in the liver of infected animals, as well as a deregulation of enzymatic antioxidant components. Collectively, this is the first study to report that oxidative stress occurs in MAYV infection in vivo, and that it may be crucial in virus pathogenesis. Future studies are warranted to address the alternative therapeutic strategies for Mayaro fever, such as those based on antioxidant compounds
Fat matters: Fermented whole milk potentiates the anti-colitis effect of Propionibacterium freudenreichii
International audienceInflammatory bowel diseases (IBD) constitute a growing concern in western countries. They coincide with gut microbiota dysbiosis, including a loss of immunomodulatory bacteria. Accordingly, probiotic products containing selected immunomodulatory bacterial strains mitigate IBD. Selected strains of Propionibacterium freudenreichii display promising modulatory properties and prevent colitis in animal models. Dairy matrices protect propionibacteria immunomodulatory surface antigens during digestive transit. However, the functional role of the dairy matrix components in such fermented dairy products remains unknown. In the present workthis study, P. freudenreichii CIRM-BIA129, a probiotic strain known for its anti-inflammatory properties, was used to ferment whole milk, skim milk or skim milk ultrafiltrate. The preventive potential of fermented products was tested in DSS-induced mice colitis, in comparison with their unfermented counterparts. P. freudenreichii-fermented milk prevented colitis. Dairy fat in the fermented product potentiated the anti-colitis effects of the probiotic. This work opens new perspectives for developing immunomodulatory functional fermented foods
Comprehensive probiogenomics analysis of the commensal Escherichia coli CEC15 as a potential probiotic strain
Abstract Background Probiotics have gained attention for their potential maintaining gut and immune homeostasis. They have been found to confer protection against pathogen colonization, possess immunomodulatory effects, enhance gut barrier functionality, and mitigate inflammation. However, a thorough understanding of the unique mechanisms of effects triggered by individual strains is necessary to optimize their therapeutic efficacy. Probiogenomics, involving high-throughput techniques, can help identify uncharacterized strains and aid in the rational selection of new probiotics. This study evaluates the potential of the Escherichia coli CEC15 strain as a probiotic through in silico, in vitro, and in vivo analyses, comparing it to the well-known probiotic reference E. coli Nissle 1917. Genomic analysis was conducted to identify traits with potential beneficial activity and to assess the safety of each strain (genomic islands, bacteriocin production, antibiotic resistance, production of proteins involved in host homeostasis, and proteins with adhesive properties). In vitro studies assessed survival in gastrointestinal simulated conditions and adhesion to cultured human intestinal cells. Safety was evaluated in BALB/c mice, monitoring the impact of E. coli consumption on clinical signs, intestinal architecture, intestinal permeability, and fecal microbiota. Additionally, the protective effects of both strains were assessed in a murine model of 5-FU-induced mucositis. Results CEC15 mitigates inflammation, reinforces intestinal barrier, and modulates intestinal microbiota. In silico analysis revealed fewer pathogenicity-related traits in CEC15, when compared to Nissle 1917, with fewer toxin-associated genes and no gene suggesting the production of colibactin (a genotoxic agent). Most predicted antibiotic-resistance genes were neither associated with actual resistance, nor with transposable elements. The genome of CEC15 strain encodes proteins related to stress tolerance and to adhesion, in line with its better survival during digestion and higher adhesion to intestinal cells, when compared to Nissle 1917. Moreover, CEC15 exhibited beneficial effects on mice and their intestinal microbiota, both in healthy animals and against 5FU-induced intestinal mucositis. Conclusions These findings suggest that the CEC15 strain holds promise as a probiotic, as it could modulate the intestinal microbiota, providing immunomodulatory and anti-inflammatory effects, and reinforcing the intestinal barrier. These findings may have implications for the treatment of gastrointestinal disorders, particularly some forms of diarrhea