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1.
BMC Microbiol ; 23(1): 364, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38008714

RESUMO

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.


Assuntos
Proteínas de Escherichia coli , Mucosite , Probióticos , Camundongos , Humanos , Animais , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Inflamação , Probióticos/uso terapêutico
2.
World J Microbiol Biotechnol ; 39(9): 235, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37365380

RESUMO

Intestinal mucositis is a commonly reported side effect in oncology patients undergoing chemotherapy and radiotherapy. Probiotics, prebiotics, and synbiotics have been investigated as alternative therapeutic approaches against intestinal mucositis due to their well-known anti-inflammatory properties and health benefits to the host. Previous studies showed that the potential probiotic Lactobacillus delbrueckii CIDCA 133 and the prebiotic Fructooligosaccharides (FOS) alleviated the 5-Fluorouracil (5-FU) chemotherapy-induced intestinal mucosa damage. Based on these previous beneficial effects, this work evaluated the anti-inflammatory property of the synbiotic formulation containing L. delbrueckii CIDCA 133 and FOS in mice intestinal mucosa inflammation induced by 5-FU. This work showed that the synbiotic formulation was able to modulate inflammatory parameters, including reduction of cellular inflammatory infiltration, gene expression downregulation of Tlr2, Nfkb1, and Tnf, and upregulation of the immunoregulatory Il10 cytokine, thus protecting the intestinal mucosa from epithelial damage caused by the 5-FU. The synbiotic also improved the epithelial barrier function by upregulating mRNA transcript levels of the short chain fatty acid (SCFA)-associated GPR43 receptor and the occludin tight junction protein, with the subsequent reduction of paracellular intestinal permeability. The data obtained showed that this synbiotic formulation could be a promising adjuvant treatment to be explored against inflammatory damage caused by 5-FU chemotherapy.


Assuntos
Antineoplásicos , Lactobacillus delbrueckii , Mucosite , Probióticos , Simbióticos , Camundongos , Animais , Mucosite/induzido quimicamente , Mucosite/tratamento farmacológico , Mucosite/prevenção & controle , Probióticos/farmacologia , Mucosa Intestinal , Prebióticos/efeitos adversos , Fluoruracila/efeitos adversos , Antineoplásicos/farmacologia
3.
Arch Virol ; 166(2): 347-361, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33410995

RESUMO

Mayaro fever is an infection caused by Mayaro virus (MAYV) that stands out among the neglected diseases transmitted by arthropods. Brazil is the country with the highest number of confirmed cases of MAYV infection. However, epidemiological surveillance studies conducted in Brazil are decentralized and focus on small outbreaks and unconfirmed cases. Thus, the aim of this review was to determine the general epidemiological profile of MAYV infections in Brazil. Several medical databases (i.e., PUBMED/MEDLINE, Scopus, Cochrane Library, LILACS, SciELO, and Biblioteca Virtual em Saúde) were searched for studies reporting cases of MAYV infections in Brazilian patients. Then, the rate of exposure to MAYV in Brazil was analyzed using RStudio® Software. We identified 37 studies published from 1957 to 2019, containing data of 12,374 patients from 1955 to 2018. The general rate of exposure to MAYV in Brazil was 10% (95% CI; 0.04-0.22), with 1,304 reported cases. The highest incidence of MAYV infection was found in the northern region (13%; 95% CI; 0.05-0.29), with 1,142 cases (88% of all cases). Furthermore, autochthonous MAYV cases have also been reported in the Central West (8%; 95% CI; 0.03-0.18) and Southeast (0.4%; 95% CI; 0.00-0.28). The states with the highest number of cases are Amazonas (490 cases), Pará (276 cases), and Goiás (87 cases). In conclusion, the general rate of exposure to MAYV in Brazil between 1955 and 2018 was considerable, especially in the Legal Amazon, in which 93% of cases were reported.


Assuntos
Infecções por Alphavirus/epidemiologia , Infecções por Alphavirus/virologia , Alphavirus/patogenicidade , Animais , Brasil/epidemiologia , Surtos de Doenças , Humanos
4.
Eur J Clin Microbiol Infect Dis ; 39(8): 1427-1438, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32533271

RESUMO

We conducted a systematic review and meta-analysis to determine the rate of polymyxin resistance among Acinetobacter baumannii isolates causing infection in hospitalized patients around the world during the period of 2010-2019. The systematic review was performed on September 1, 2019, using PubMed/MEDLINE, Scopus, and Web of Science; studies published after January 1, 2010, were selected. The data were summarized in tables, critically analyzed, and treated statistically using the RStudio® Software with Meta package and Metaprop Command. After applying exclusion factors, 41 relevant studies were selected from 969 articles identified on literature search. The overall rate of polymyxin-resistant A. baumannii (PRAB) related to hospitalized patients was estimated to be 13% (95% CI, 0.06-0.27), where a higher rate was observed in America (29%; 95% CI, 0.12-0.55), followed by Europe (13%; 95% CI, 0.02-0.52), and Asia (10%; 95% CI, 0.02-0.32). The extensive use of polymyxins on veterinary to control bacterial infection and growth promotion, as well as the resurgence in prescription and use of polymyxins in the clinics against carbapenem-resistant gram-negative bacteria, may have contributed to the increased incidence of PRAB. The findings of this meta-analysis revealed that the rate of PRAB recovered from hospitalized patients is distinctively high. Thus, action needs to be taken to develop strategies to combat the clinical incidence of PRAB-induced hospital infections.


Assuntos
Infecções por Acinetobacter/tratamento farmacológico , Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Hospitalização , Polimixinas/farmacologia , Infecções por Acinetobacter/microbiologia , Antibacterianos/uso terapêutico , Humanos , Testes de Sensibilidade Microbiana , Polimixinas/uso terapêutico
5.
Rev Med Virol ; 29(5): e2056, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31172625

RESUMO

Dengue virus is known to modulate host cell lipid metabolism in order to promote efficient viral replication. Recent studies have focused on circulating lipids as potential biomarkers of dengue severity; however, the results obtained so far lack the consistency to establish a definite relationship between the two. Therefore, in the present study, we investigated serum lipids as potential biomarkers of dengue severity by conducting a meta-analysis of the currently available clinical data. Nine studies that evaluated 1,953 patients were included in the review, many of which were cross-sectional (44.4%) and conducted in Asian countries (55.5%). These studies observed the presence of lipids in serum samples (77%) of patients in the acute phase of the disease (88.8%). Circulating total-cholesterol (P = .001) and LDL (P = .001) levels, but not HDL (P = .07), VLDL (P = .9) and triglyceride (P = .57) levels, were inversely and significantly correlated with dengue severity. Total cholesterol (P ≤ .001) and LDL (P = .001) were also useful in determining the risk of hypovolemic shock in patients with severe dengue. Subgroup analysis showed that factors, such as design (cross-sectional vs cohort), racial-ethnic differences (Asian vs Latin Americans), and age range (children vs adult) influenced the correlation and also contributed to the high level of heterogeneity in the studies. Our meta-analysis demonstrates that total-cholesterol and LDL-cholesterol levels should be explored as routine laboratory markers for dengue severity, as they will help in employing an appropriate patient therapy, and thus optimize the use of available resources.


Assuntos
Biomarcadores , Dengue/sangue , Dengue/diagnóstico , Lipídeos/sangue , Humanos , Prognóstico , Viés de Publicação , Dengue Grave/sangue , Dengue Grave/diagnóstico , Índice de Gravidade de Doença
6.
Brain Behav Immun ; 81: 444-454, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31271871

RESUMO

The gastrointestinal (GI) tract harbors commensal microorganisms as well as invasive bacteria, toxins and other pathogens and, therefore, plays a pivotal barrier and immunological role against pathogenic agents. The vagus nerve is an important regulator of the GI tract-associated immune system, having profound effects on inflammatory responses. Among GI tract organs, the liver is a key site of immune surveillance, as it has a large population of resident macrophages and receives the blood drained from the guts through the hepatic portal circulation. Although it is widely accepted that the hepatic tissue is a major target for vagus nerve fibers, the role of this neural circuit in liver immune functions is still poorly understood. Herein we used in vivo imaging techniques, including confocal microscopy and scintigraphy, to show that vagus nerve stimulation increases the phagocytosis activity by resident macrophages in the liver, even on the absence of an immune challenge. The activation of this neural circuit in a non-lethal model of sepsis optimized the removal of bacteria in the liver and resulted in the production of anti-inflammatory and pro-regenerative cytokines. Our findings provide new insights into the neural regulation of the immune system in the liver.


Assuntos
Fígado/imunologia , Fagocitose/fisiologia , Nervo Vago/fisiologia , Animais , Citocinas , Feminino , Trato Gastrointestinal , Fígado/patologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Fagócitos/metabolismo , Sepse/imunologia , Nervo Vago/patologia , Estimulação do Nervo Vago/métodos
7.
Med Mycol ; 56(4): 479-484, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28992125

RESUMO

Cryptococcus gattii is one of the etiologic agents of cryptococcosis, a systemic mycosis that occurs in healthy and immunosuppressed humans and animals worldwide. Primary pulmonary infection caused by C. gattii is usually followed by fungal dissemination to the central nervous system, resulting in high mortality rates. In this context, animal models of cryptococcosis are useful in the study of fungal pathogenesis and host response against the pathogen, and for testing novel therapeutic options. The most frequently applied method to study fungal dissemination from the lungs to other organs is by culturing tissues, which is not accurate for the detection and quantification of fungal load at early stages of the infection. To overcome this problem, the purpose of this study was to develop a new method for the quantification of Cryptococcus dissemination. One C. gattii strain was efficiently radiolabeled with technetium-99m (99mTc), without affecting viability of the cells. Further, the 99mTc-C. gattii (111 MBq) strain was used to infect mice by intratracheal and intravenous route for biodistribution studies. 99mTc-C. gattii was successfully used in detection of the yeast in the brain of mice 6 hours postinoculation, while the detection using colony forming units was possible only 24 hours postinfection. Our results provided an alternative method that could be applied in further investigations regarding the efficacy of antifungals, fungal virulence, and host-pathogen interactions.


Assuntos
Criptococose/microbiologia , Cryptococcus gattii/fisiologia , Tecnécio , Animais , Contagem de Colônia Microbiana , Cryptococcus gattii/metabolismo , Modelos Animais de Doenças , Humanos , Marcação por Isótopo , Pulmão/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Tecnécio/análise , Tecnécio/metabolismo , Distribuição Tecidual
8.
Nutr Cancer ; 69(1): 168-175, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27682136

RESUMO

Mucositis is the most common side effect due to chemotherapy or radiotherapy. It refers to the inflammation of intestinal mucous membranes, and it is associated with complications such as diarrhea, weight loss, and increased intestinal permeability (IP). This study was designed to evaluate the effect of diet containing conjugated linoleic acid (CLA)-enriched butter on intestinal damage and inflammatory response after 24 h of 5-fluorouracil (5-FU)-induced mucositis. Mice were divided into four groups: CTL; CLA; 5-FU, and CLA 5-FU, and they were fed for 31 days. On the 30th experimental day, mucositis was induced by unique injection of 300 mg/kg of 5-FU. After 24 h (31st experimental day), IP was evaluated; ileum and fecal material were collected to determine cytokine level and myeloperoxidase (MPO) activity and secretory immunoglobulin A (sIgA). The 5-FU group showed an increase in IP and MPO activity (CTL vs. 5-FU: P < 0.05). Additionally, increased levels of IP and MPO were observed in CLA 5-FU group compared to those in the test groups (P < 0.05). Animals in the CLA 5-FU group showed reduced concentrations of sIgA (CTL vs. CLA 5-FU: P < 0.05). CLA-enriched butter exacerbating the 5-FU-induced intestinal damage. Safety concerns regarding the use of CLA require further investigation.


Assuntos
Manteiga , Mucosa Intestinal/patologia , Ácidos Linoleicos Conjugados/farmacologia , Mucosite/dietoterapia , Animais , Peso Corporal , Quimiocinas/metabolismo , Citocinas/metabolismo , Fluoruracila/efeitos adversos , Alimentos Fortificados , Imunoglobulina A/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Intestinos/fisiopatologia , Masculino , Camundongos Endogâmicos BALB C , Mucosite/induzido quimicamente , Permeabilidade , Peroxidase/metabolismo
9.
Nanomedicine ; 13(5): 1693-1701, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28343016

RESUMO

Chemotherapy for bone tumors is a major challenge because of the inability of therapeutics to penetrate dense bone mineral. We hypothesize that a nanostructured formulation with high affinity for bone could deliver drug to the tumor while minimizing off-target toxicity. Here, we evaluated the efficacy and toxicity of a novel bone-targeted, pH-sensitive liposomal formulation containing doxorubicin in an animal model of bone metastasis. Biodistribution studies with the liposome showed good uptake in tumor, but low accumulation of doxorubicin in the heart. Mice treated with the bone-targeted liposome formulation showed a 70% reduction in tumor volume, compared to 35% reduction for free doxorubicin at the same dose. Both cardiac toxicity and overall mortality were significantly lower for animals treated with the bone-targeted liposomes compared to free drug. Bone-targeted, pH-sensitive, doxorubicin containing liposomes represent a promising approach to selectively delivering doxorubicin to bone tumors while minimizing cardiac toxicity.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Neoplasias Ósseas/tratamento farmacológico , Doxorrubicina/administração & dosagem , Lipossomos , Animais , Antibióticos Antineoplásicos/toxicidade , Neoplasias Ósseas/secundário , Cardiotoxicidade , Doxorrubicina/toxicidade , Concentração de Íons de Hidrogênio , Camundongos , Distribuição Tecidual
10.
J Nutr ; 144(2): 218-23, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24259555

RESUMO

Dietary supplementation with l-arginine has been shown to improve the intestinal barrier in many experimental models. This study investigated the effects of arginine supplementation on the intestinal permeability and bacterial translocation (BT) induced by prolonged physical exercise under heat stress. Under anesthesia, male Swiss mice (5-wk-old) were implanted with an abdominal sensor to record their core body temperature (T(core)). After recovering from surgery, the mice were divided into 3 groups: a non-supplemented group that was fed the standard diet formulated by the American Institute of Nutrition (AIN-93G; control), a non-supplemented group that was fed the AIN-93G diet and subjected to exertional hyperthermia (H-NS), and a group supplemented with l-arginine at 2% and subjected to exertional hyperthermia (H-Arg). After 7 d of treatment, the H-NS and H-Arg mice were forced to run on a treadmill (60 min, 8 m/min) in a warm environment (34°C). The control mice remained at 24°C. Thirty min before the exercise or control trials, the mice received a diethylenetriamine pentaacetic acid (DTPA) solution labeled with technetium-99m ((99m)Tc-DTPA) or (99m)Tc-Escherichia coli by gavage to assess intestinal permeability and BT, respectively. The H-NS mice terminated the exercise with T(core) values of ∼40°C, and, 4 h later, presented a 12-fold increase in the blood uptake of (99m)Tc-DTPA and higher bacterial contents in the blood and liver than the control mice. Although supplementation with arginine did not change the exercise-induced increase in T(core), it prevented the increases in intestinal permeability and BT caused by exertional hyperthermia. Our results indicate that dietary l-arginine supplementation preserves the integrity of the intestinal epithelium during exercise under heat stress, acting through mechanisms that are independent of T(core) regulation.


Assuntos
Arginina/uso terapêutico , Translocação Bacteriana/efeitos dos fármacos , Suplementos Nutricionais , Febre/complicações , Mucosa Intestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Condicionamento Físico Animal/fisiologia , Animais , Arginina/farmacologia , Temperatura Corporal/efeitos dos fármacos , Escherichia coli , Febre/patologia , Temperatura Alta , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Intestinos/microbiologia , Intestinos/patologia , Fígado/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos , Ácido Pentético/sangue , Permeabilidade , Corrida/fisiologia , Estresse Fisiológico
11.
J Negat Results Biomed ; 13: 6, 2014 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-24721659

RESUMO

BACKGROUND: The antimetabolite chemotherapy 5-Fluorouracil is one of the most commonly prescribed drugs in clinical cancer treatment. Although this drug is not specific for cancer cells and also acts on healthy cells, it can cause mucositis, a common collateral effect. Dysbiosis has also been described in 5-fluorouracil-induced mucositis and is likely to contribute to the overall development of mucositis. In light of this theory, the use of probiotics could be a helpful strategy to alleviate mucositis. So the aim of this study was evaluate the impact of the probiotic Saccharomyces boulardii in a model of mucositis. RESULTS: After induced of mucositis, mice from the Mucositis groups showed a decrease in food consumption (p < 0.05) and therefore had a greater weight loss (p < 0.05). The treatment with Saccharomyces boulardii did not reverse this effect (p > 0.05). Mucositis induced an increase in intestinal permeability and intestinal inflammation (p < 0.05). There were no differences in mucosal lesions, intestinal permeability and sIgA secretion (p > 0.05) in mice pretreated with S. boulardii. CONCLUSIONS: S. boulardii was not able to prevent the effects of experimental mucositis induced by 5- Fluorouracil.


Assuntos
Mucosite/prevenção & controle , Probióticos , Saccharomyces , Animais , Antimetabólitos Antineoplásicos/efeitos adversos , Comportamento Alimentar , Fluoruracila/efeitos adversos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Camundongos , Mucosite/induzido quimicamente , Redução de Peso
12.
Artigo em Inglês | MEDLINE | ID: mdl-38321899

RESUMO

INTRODUCTION: Active targeting of tumors by nanomaterials favors early diagnosis and the reduction of harsh side effects of chemotherapeuticals. METHOD: We synthesized magnetic nanoparticles (64 nm; -40 mV) suspended in a magnetic fluid (MF) and decorated them with anti-carcinoembryonic antigen (MFCEA; 144 nm; -39 mV). MF and MFCEA nanoparticles were successfully radiolabeled with technetium-99m (99mTc) and intravenously injected in CEA-positive 4T1 tumor-bearing mice to perform biodistribution studies. Both 99mTc-MF and 99mTc-MFCEA had marked uptake by the liver and spleen, and the renal uptake of 99mTc-MFCEA was higher than that observed for 99mTc-MF at 20h. At 1 and 5 hours, the urinary excretion was higher for 99mTc-MF than for 99mTc-MFCEA. RESULTS: These data suggest that anti-CEA decoration might be responsible for a delay in renal clearance. Regarding the tumor, 99mTc-MFCEA showed tumor uptake nearly two times higher than that observed for 99mTc-MFCEA. Similarly, the target-nontarget ratio was higher with 99mTc-MFCEA when compared to the group that received the 99mTc-MF. CONCLUSION: These data validated the ability of active tumor targeting by the as-developed antiCEA loaded nanoparticles and are very promising results for the future development of a nanodevice for the management of breast cancer and other types of CEA-positive tumors.

13.
J Chemother ; : 1-18, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38711347

RESUMO

Chemotherapy-induced intestinal mucositis is a major side effect of cancer treatment. Statins are 3-hydroxy-3-methyl glutaryl coenzyme reductase inhibitors used to treat hypercholesterolemia and atherosclerotic diseases. Recent studies have demonstrated that atorvastatin (ATV) has antioxidant, anti-inflammatory, and resulting from the regulation of different molecular pathways. In the present study, we investigated the effects of ATV on intestinal homeostasis in 5-fluorouracil (5-FU)-induced mucositis. Our results showed that ATV protected the intestinal mucosa from epithelial damage caused by 5-FU mainly due to inflammatory infiltrate and intestinal permeability reduction, downregulation of inflammatory markers, such as Tlr4, MyD88, NF-κB, Tnf-a, Il1ß, and Il6 dose-dependent. ATV also improved epithelial barrier function by upregulating the mRNA transcript levels of mucin 2 (MUC2), and ZO-1 and occludin tight junction proteins. The results suggest that the ATV anti-inflammatory and protective effects on 5-FU-induced mice mucositis involve the inhibition of the TLR4/MYD88/NPRL3/NF-κB, iNos, and caspase 3.

14.
Antibiotics (Basel) ; 13(3)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38534683

RESUMO

The urgent global health challenge posed by methicillin-resistant Staphylococcus aureus (MRSA) infections demands effective solutions. Antimicrobial peptides (AMPs) represent promising tools of research of new antibacterial agents and LyeTx I mn∆K, a short synthetic peptide based on the Lycosa erythrognatha spider venom, is a good representative. This study focused on analyzing the antimicrobial activities of LyeTx I mn∆K, including minimum inhibitory and bactericidal concentrations, synergy and resensitization assays, lysis activity, the effect on biofilm, and the bacterial death curve in MRSA. Additionally, its characterization was conducted through isothermal titration calorimetry, dynamic light scattering, calcein release, and finally, efficacy in a mice wound model. The peptide demonstrates remarkable efficacy against planktonic cells (MIC 8-16 µM) and biofilms (>30% of inhibition) of MRSA, and outperforms vancomycin in terms of rapid bactericidal action and anti-biofilm effects. The mechanism involves significant membrane damage. Interactions with bacterial model membranes, including those with lysylphosphatidylglycerol (LysylPOPG) modifications, highlight the versatility and selectivity of this compound. Also, the peptide has the ability to sensitize resistant bacteria to conventional antibiotics, showing potential for combinatory therapy. Furthermore, using an in vivo model, this study showed that a formulated gel containing the peptide proved superior to vancomycin in treating MRSA-induced wounds in mice. Together, the results highlight LyeTx I mnΔK as a promising prototype for the development of effective therapeutic strategies against superficial MRSA infections.

15.
ACS Pharmacol Transl Sci ; 7(7): 2143-2153, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39022369

RESUMO

Capsaicin, a pungent compound in chili peppers, is described as having potent anti-inflammatory, antioxidant, and antimicrobial properties. It is also described as a potential modulator of the immune system and intestinal microbiota. Oral or rectal administration of capsaicin has been studied to treat or prevent colitis. However, those vias are often not well accepted due to the burning sensation that capsaicin can cause. Our objective was to evaluate whether the application of capsaicin skin creams (0.075%) would be effective in improving inflammation and epithelial barrier function as well as the composition of the gut microbiota in a model of mild colitis induced by dextran sulfate sodium (1.5%). The results showed that the cutaneous application of capsaicin reversed weight loss and decreased colon shortening and diarrhea, all typical signs of colitis. There was also an improvement in the intestinal epithelial barrier, preserving proteins from tight junctions. We also evaluated the biodistribution of 99mtechnetium-radiolabeled capsaicin (99mTc-CAPS) applied to the back skin of the animals. We found significant concentrations of 99 mTc-Cap in the colon and small intestine after 2 and 4 h of administration. In addition, there was an increased expression of capsaicin receptor TRPV1 in the colon. Moreover, animals with colitis receiving cutaneous capsaicin presented a better short-chain fatty acid profile and increased levels of SIgA, suggesting increased microbiota diversity. In conclusion, our work opens avenues for further studies to better understand capsaicin's potential benefits and mechanisms in addressing colitis through cutaneous application.

16.
Int J Biol Macromol ; 277(Pt 2): 134216, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39069058

RESUMO

Lactobacillus delbrueckii CIDCA 133 is a promising health-promoting bacterium shown to alleviate intestinal inflammation. However, the specific bacterial components responsible for these effects remain largely unknown. Here, we demonstrated that consuming extractable proteins from the CIDCA 133 strain effectively relieved acute ulcerative colitis in mice. This postbiotic protein fraction reduced the disease activity index and prevented colon shortening in mice. Furthermore, histological analysis revealed colitis prevention with reduced inflammatory cell infiltration into the colon mucosa. Postbiotic consumption also induced an immunomodulatory profile in colitic mice, as evidenced by both mRNA transcript levels (Tlr2, Nfkb1, Nlpr3, Tnf, and Il6) and cytokines concentration (IL1ß, TGFß, and IL10). Additionally, it enhanced the levels of secretory IgA, upregulated the transcript levels of tight junction proteins (Hp and F11r), and improved paracellular intestinal permeability. More interestingly, the consumption of postbiotic proteins modulated the gut microbiota (Bacteroides, Arkkemansia, Dorea, and Oscillospira). Pearson correlation analysis indicated that IL10 and IL1ß levels were positively associated with Bacteroides and Arkkemansia_Lactobacillus abundance. Our study reveals that CIDCA 133-derived proteins possess anti-inflammatory properties in colonic inflammation.

17.
Food Res Int ; 186: 114322, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729712

RESUMO

Lactobacillus delbrueckii subsp. lactis CIDCA 133 is a health-promoting bacterium that can alleviate gut inflammation and improve the epithelial barrier in a mouse model of mucositis. Despite these beneficial effects, the protective potential of this strain in other inflammation models, such as inflammatory bowel disease, remains unexplored. Herein, we examined for the first time the efficacy of Lactobacillus delbrueckii CIDCA 133 incorporated into a fermented milk formulation in the recovery of inflammation, epithelial damage, and restoration of gut microbiota in mice with dextran sulfate sodium-induced colitis. Oral administration of Lactobacillus delbrueckii CIDCA 133 fermented milk relieved colitis by decreasing levels of inflammatory factors (myeloperoxidase, N-acetyl-ß-D-glucosaminidase, toll-like receptor 2, nuclear factor-κB, interleukins 10 and 6, and tumor necrosis factor), secretory immunoglobulin A levels, and intestinal paracellular permeability. This immunobiotic also modulated the expression of tight junction proteins (zonulin and occludin) and the activation of short-chain fatty acids-related receptors (G-protein coupled receptors 43 and 109A). Colonic protection was effectively associated with acetate production and restoration of gut microbiota composition. Treatment with Lactobacillus delbrueckii CIDCA 133 fermented milk increased the abundance of Firmicutes members (Lactobacillus genus) while decreasing the abundance of Proteobacteria (Helicobacter genus) and Bacteroidetes members (Bacteroides genus). These promising outcomes influenced the mice's mucosal healing, colon length, body weight, and disease activity index, demonstrating that this immunobiotic could be explored as an alternative approach for managing inflammatory bowel disease.


Assuntos
Colite , Produtos Fermentados do Leite , Sulfato de Dextrana , Microbioma Gastrointestinal , Lactobacillus delbrueckii , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Colite/microbiologia , Colite/induzido quimicamente , Colite/metabolismo , Colite/tratamento farmacológico , Lactobacillus delbrueckii/metabolismo , Produtos Fermentados do Leite/microbiologia , Camundongos , Probióticos/uso terapêutico , Masculino , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Mucosa Intestinal/microbiologia , Mucosa Intestinal/metabolismo , Inflamação , Colo/microbiologia , Colo/metabolismo , Lactobacillus
18.
Nat Prod Res ; 37(5): 759-763, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35731024

RESUMO

The increase in the incidence of fungal infections associated with the limited therapeutic arsenal available and the increasing rate of resistance of pathogenic fungi reinforce the need for research of new antifungal agents. Thus, this study aims to evaluate the antifungal activity of the peptide LyeTx I mnΔK, a shortened analogue of the natural peptide LyeTx I derived from spider venom, against Candida species. LyeTx I mnΔK showed potent activity against Candida spp. with minimum inhibitory concentration (MIC) and minimum fungicide concentration (MFC) between 4 and 32 µM. The peptide also completely inhibited the yeast-to-hypha transition (at 2 µM) and broke mature biofilms (67% reduction at 32 µM) of C. albicans. In addition, LyeTx I mnΔK did not induce resistance in C. albicans during 21 days of exposure. Therefore, the LyeTx I mnΔK is a promising prototype for the development of new antifungal agents.


Assuntos
Antifúngicos , Peçonhas , Antifúngicos/farmacologia , Candida , Candida albicans , Peptídeos/farmacologia , Testes de Sensibilidade Microbiana , Biofilmes
19.
Fundam Clin Pharmacol ; 37(3): 493-507, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36514874

RESUMO

Ulcerative Colitis (UC) is a chronic inflammatory condition of the large intestines. Although great advances have been made in the management of the disease with the introduction of immunomodulators and biological agents, the treatment of UC is still a challenge. So far, there are no definitive therapies for this condition. Statins are potent inhibitors of cholesterol biosynthesis, possess beneficial effects on primary and secondary prevention of coronary heart disease, and have high tolerability and safety. Furthermore, they may have potential roles in UC management due to their possible anti-inflammatory, immunomodulatory, and antioxidant activities. This systematic review aimed to gather information about the potential benefits of statins for managing UC, reducing inflammation and disease remission in animal models. A systematic search was performed in PubMed/MEDLINE, Scopus, Web of Science, and Virtual Health Library. The data were summarized in tables and critically analyzed. After the database search, 21 relevant studies were identified as eligible for this review. Preclinical studies using several colitis-induction protocols and various statins have shown numerous beneficial effects of these drugs on reducing disease activity, inflammatory profile, oxidative stress, and general clinical parameters of animals with UC. These studies revealed the potential of statins against the pathogenesis of UC. However, there are still important gaps regarding the molecular mechanisms of action of statins, leading to some contradictory results. Thus, more research on the molecular level to determine the roles of statins in colitis should be carried out to elucidate their mechanisms of action.


Assuntos
Colite Ulcerativa , Colite , Inibidores de Hidroximetilglutaril-CoA Redutases , Animais , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/prevenção & controle , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Inflamação/tratamento farmacológico
20.
Int J Pharm ; 631: 122505, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36549405

RESUMO

The aim of this study was to develop, characterize and evaluate the in vivo oral efficacy of self-emulsifying drug delivery systems (SEDDS) containing fexinidazole (FEX) in the experimental treatment of visceral leishmaniasis (VL). The developed FEX-SEDDS formulation presented as a clear, yellowish liquid, with absence of precipitate. The droplet size, polydispersion index and zeta potential after dilution in water (1:200) was of 91 ± 3 nm, 0.242 ± 0.005 and -16.7 ± 0.2, respectively. In the simulated gastric and intestinal media, the FEX-SEDDS had a size of 97 ± 1 and 106 ± 9 nm, respectively. The FEX retention in droplet after SEDDS dilution in simulated gastrointestinal media was almost 100 %. Antileishmanial efficacy studies showed that FEX-SEDDS was the only treatment able to significantly (p < 0.05) reduce the parasite burden in the liver and spleen of animals experimentally infected with Leishmania infantum. Our intestinal permeability data suggest that FEX-SEDDS showed no evidence of injury to the intestinal mucosa. These findings suggest that FEX-SEDDS can be a promising oral alternative for the treatment of VL caused by L. infantum.


Assuntos
Antiprotozoários , Nitroimidazóis , Animais , Emulsões , Sistemas de Liberação de Medicamentos , Antiprotozoários/farmacologia , Administração Oral , Solubilidade , Emulsificantes
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