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1.
Proc Natl Acad Sci U S A ; 117(12): 6630-6639, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32161138

RESUMO

Aging elicits quantitative and qualitative changes in different immune components, leading to disruption of tolerogenic circuits and development of autoimmune disorders. Galectin-1 (Gal1), an endogenous glycan-binding protein, has emerged as a regulator of immune cell homeostasis by shaping the fate of myeloid and lymphoid cells. Here, we demonstrate that aged Gal1-null mutant (Lgals1-/- ) mice develop a spontaneous inflammatory process in salivary glands that resembles Sjögren's syndrome. This spontaneous autoimmune phenotype was recapitulated in mice lacking ß1,6N-acetylglucosaminyltransferase V (Mgat5), an enzyme responsible for generating ß1,6-branched complex N-glycans, which serve as a major ligand for this lectin. Lack of Gal1 resulted in CD11c+ dendritic cells (DCs) with higher immunogenic potential, lower frequency of Foxp3+ regulatory T cells (Tregs), and increased number of CD8+ T cells with greater effector capacity. Supporting its tolerogenic activity, Gal1 expression decreased with age in autoimmunity-prone nonobese diabetic (NOD) mice. Treatment with recombinant Gal1 restored tolerogenic mechanisms and reduced salivary gland inflammation. Accordingly, labial biopsies from primary Sjögren's syndrome patients showed reduced Gal1 expression concomitant with higher number of infiltrating CD8+ T cells. Thus, endogenous Gal1 serves as a homeostatic rheostat that safeguards immune tolerance and prevents age-dependent development of spontaneous autoimmunity.


Assuntos
Doenças Autoimunes/patologia , Galectina 1/fisiologia , Tolerância Imunológica/imunologia , Glândulas Salivares/patologia , Sialadenite/patologia , Síndrome de Sjogren/patologia , Linfócitos T Reguladores/imunologia , Adulto , Fatores Etários , Animais , Doenças Autoimunes/imunologia , Doenças Autoimunes/metabolismo , Estudos de Casos e Controles , Células Dendríticas/imunologia , Feminino , Glicosilação , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Pessoa de Meia-Idade , N-Acetilglucosaminiltransferases/fisiologia , Polissacarídeos/metabolismo , Glândulas Salivares/imunologia , Glândulas Salivares/metabolismo , Sialadenite/imunologia , Sialadenite/metabolismo , Síndrome de Sjogren/imunologia , Síndrome de Sjogren/metabolismo
2.
Med Mycol ; 59(12): 1210-1224, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34468763

RESUMO

Spilanthol is a bioactive alkylamide from the native Amazon plant species, Acmella oleracea. However, antifungal activities of spilanthol and its application to the therapeutic treatment of candidiasis remain to be explored. This study sought to evaluate the in vitro and in vivo antifungal activity of spilanthol previously isolated from A. oleracea (spilanthol(AcO)) against Candida albicans ATCC® 10231™, a multidrug-resistant fungal strain. Microdilution methods were used to determine inhibitory and fungicidal concentrations of spilanthol(AcO). In planktonic cultures, the fungal growth kinetics, yeast cell metabolic activity, cell membrane permeability and cell wall integrity were investigated. The effect of spilanthol(AcO) on the proliferation and adhesion of fungal biofilms was evaluated by whole slide imaging and scanning electron microscopy. The biochemical composition of the biofilm matrix was also analyzed. In parallel, spilanthol(AcO) was tested in vivo in an experimental vulvovaginal candidiasis model. Our in vitro analyses in C. albicans planktonic cultures detected a significant inhibitory effect of spilanthol(AcO), which affects both yeast cell membrane and cell wall integrity, interfering with the fungus growth. C. albicans biofilm proliferation and adhesion, as well as, carbohydrates and DNA in biofilm matrix were reduced after spilanthol(AcO) treatment. Moreover, infected rats treated with spilanthol(AcO) showed consistent reduction of both fungal burden and inflammatory processes compared to the untreated animals. Altogether, our findings demonstrated that spilanthol(AcO) is an bioactive compound against planktonic and biofilm forms of a multidrug resistant C. albicans strain. Furthermore, spilanthol(AcO) can be potentially considered for therapeutical treatment of vulvovaginal candidiasis caused by C. albicans. LAY SUMMARY: This study sought to evaluate the antifungal activity of spilanthol against Candida albicans ATCC® 10 231™, a multidrug-resistant fungal strain. Our findings demonstrated that spilanthol(AcO) can be potentially considered for therapeutical treatment of vulvovaginal candidiasis caused by C. albicans.


Assuntos
Candidíase Vulvovaginal , Doenças dos Roedores , Animais , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Biofilmes , Candida albicans , Candidíase Vulvovaginal/tratamento farmacológico , Candidíase Vulvovaginal/veterinária , Testes de Sensibilidade Microbiana/veterinária , Alcamidas Poli-Insaturadas/farmacologia , Ratos , Doenças dos Roedores/tratamento farmacológico
3.
Pediatr Blood Cancer ; 68(7): e29115, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33991404

RESUMO

Targeted therapies with MAPK inhibitors have proven to modulate the clinical manifestations of patients with Langerhans cell histiocytosis (LCH). We explored the presence of BRAFV600E mutation in our cohort of patients with LCH and cholestasis, sclerosing cholangitis, or liver fibrosis that presented resistance to chemotherapy. The BRAFV600E mutation was detected either in the diagnosis (skin and bone) or liver biopsy in our cohort of 13 patients. Thus, we observed a high incidence of BRAFV600E mutation in 100% either in diagnostic biopsy (skin and bone) or liver biopsy in patients with progressive liver disease, sequela, or liver transplant requirement.


Assuntos
Colangite Esclerosante , Colestase , Histiocitose de Células de Langerhans , Proteínas Proto-Oncogênicas B-raf/genética , Colangite Esclerosante/complicações , Colangite Esclerosante/epidemiologia , Colangite Esclerosante/genética , Colestase/complicações , Colestase/genética , Histiocitose de Células de Langerhans/epidemiologia , Histiocitose de Células de Langerhans/etiologia , Histiocitose de Células de Langerhans/genética , Humanos , Cirrose Hepática , Mutação , Prevalência
4.
An Acad Bras Cienc ; 93(suppl 4): e20210457, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34852065

RESUMO

Syzygium malaccense is popularly used to treat inflammation and pain-related ailments. The species was assessed regarding its antioxidant, antiglycant, anti-inflammatory, including anti-neuroinflammatory, and antinociceptive activities. Different models were employed to measure S. malaccense extract (ESM) antioxidant activity. The antiglycant activity was determined using the glucose-induced protein glycation model. LPS-induced neuroinflammation on murine BV-2 microglial cell line was used for anti-neuroinflammatory activity evaluation. The croton oil-induced ear edema test was accomplished to evaluate the in vivo anti-inflammatory activity. Acetic acid-induced writhing together with formalin-induced paw licking assays were performed to evaluate the antinociceptive potential. Finally, the chemical characterization was accomplished by a UHPLC-MS analysis. ESM presented relevant antioxidant and antiglycant activity. NO production by BV-2 cells was reduced, indicating the relevant neuroprotective activity. ESM significantly decreased the mice ear edema induced by croton oil and the nociceptive stimulus induced by acetic acid and formalin by central and peripheral mechanisms. The flavonoids myricitrin, myricetin and quercetin were identified and, as far as we know, the alkaloid reserpine was reported in the species for the first time. The antioxidant and antiglycant potential of ESM, may be related to the in vivo anti-inflammatory and antinociceptive effects, and to the in vitro neuroinflammation inhibition.


Assuntos
Antioxidantes , Syzygium , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Edema/induzido quimicamente , Edema/tratamento farmacológico , Camundongos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
5.
J Biol Chem ; 293(25): 9924-9936, 2018 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-29743243

RESUMO

To fertilize an egg, sperm must reside in the female reproductive tract to undergo several maturational changes that are collectively referred to as capacitation. From a molecular point of view, the HCO3--dependent activation of the atypical soluble adenylyl cyclase (ADCY10) is one of the first events that occurs during capacitation and leads to the subsequent cAMP-dependent activation of protein kinase A (PKA). Capacitation is also accompanied by hyperpolarization of the sperm plasma membrane. We previously reported that PKA activation is necessary for CFTR (cystic fibrosis transmembrane conductance regulator channel) activity and for the modulation of membrane potential (Em). However, the main HCO3- transporters involved in the initial transport and the PKA-dependent Em changes are not well known nor characterized. Here, we analyzed how the activity of CFTR regulates Em during capacitation and examined its relationship with an electrogenic Na+/HCO3- cotransporter (NBC) and epithelial Na+ channels (ENaCs). We observed that inhibition of both CFTR and NBC decreased HCO3- influx, resulting in lower PKA activity, and that events downstream of the cAMP activation of PKA are essential for the regulation of Em. Addition of a permeable cAMP analog partially rescued the inhibitory effects caused by these inhibitors. HCO3- also produced a rapid membrane hyperpolarization mediated by ENaC channels, which contribute to the regulation of Em during capacitation. Altogether, we demonstrate for the first time, that NBC cotransporters and ENaC channels are essential in the CFTR-dependent activation of the cAMP/PKA signaling pathway and Em regulation during human sperm capacitation.


Assuntos
Bicarbonatos/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Canais Epiteliais de Sódio/metabolismo , Potenciais da Membrana , Capacitação Espermática , Espermatozoides/fisiologia , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Humanos , Masculino , Fosforilação , Transdução de Sinais , Sódio/metabolismo , Simportadores de Sódio-Bicarbonato/metabolismo
6.
Bioorg Med Chem ; 26(17): 4898-4906, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-30193941

RESUMO

Resveratrol is a natural polyphenol found mainly on red grapes and in red wine, pointed as an important anti-inflammatory/immunomodulatory molecule. However, its bioavailability problems have limited its use encouraging the search for new alternatives agents. Thus, in this study, we synthetize 12 resveratrol analogues (6 imines, 1 thioimine and 5 hydrazones) and investigated its cytotoxicity, antioxidant activity and in vitro anti-inflammatory/immunomodulatory properties. The most promising compounds were also evaluated in vivo. The results showed that imines presented less cytotoxicity, were more effective than resveratrol on DPPH scavenger and exhibited an anti-inflammatory profile. Among them, the imines with a radical in the para position, on the ring B, not engaged in an intramolecular hydrogen-interaction, showed more prominent anti-inflammatory activity modulating, in vivo, the edema formation, the inflammatory infiltration and cytokine levels. An immunomodulatory activity also was observed in these molecules. Thus, our results suggest that imines with these characteristics presents potential to control inflammatory disorders.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Iminas/química , Resveratrol/análogos & derivados , Adjuvantes Imunológicos/farmacologia , Animais , Anti-Inflamatórios/farmacocinética , Antioxidantes/farmacologia , Disponibilidade Biológica , Compostos de Bifenilo/metabolismo , Proliferação de Células/efeitos dos fármacos , Citocinas/antagonistas & inibidores , Citocinas/biossíntese , Regulação para Baixo/efeitos dos fármacos , Inflamação/prevenção & controle , Mediadores da Inflamação/antagonistas & inibidores , Mediadores da Inflamação/metabolismo , Linfócitos/citologia , Linfócitos/efeitos dos fármacos , Complexo Principal de Histocompatibilidade/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Peroxidase/biossíntese , Picratos/metabolismo , Células RAW 264.7
7.
J Cell Physiol ; 232(6): 1404-1414, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27714810

RESUMO

Mammalian sperm require to spend a limited period of time in the female reproductive tract to become competent to fertilize in a process called capacitation. It is well established that HCO3- is essential for capacitation because it activates the atypical soluble adenylate cyclase ADCY10 leading to cAMP production, and promotes alkalinization of cytoplasm, and membrane hyperpolarization. However, how HCO3- is transported into the sperm is not well understood. There is evidence that CFTR activity is involved in the human sperm capacitation but how this channel is integrated in the complex signaling cascades associated with this process remains largely unknown. In the present work, we have analyzed the extent to which CFTR regulates different events in human sperm capacitation. We observed that inhibition of CFTR affects HCO3- -entrance dependent events resulting in lower PKA activity. CFTR inhibition also affected cAMP/PKA-downstream events such as the increase in tyrosine phosphorylation, hyperactivated motility, and acrosome reaction. In addition, we demonstrated for the first time, that CFTR and PKA activity are essential for the regulation of intracellular pH, and membrane potential in human sperm. Addition of permeable cAMP partially recovered all the PKA-dependent events altered in the presence of inh-172 which is consistent with a role of CFTR upstream of PKA activation. J. Cell. Physiol. 232: 1404-1414, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Álcalis/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Potenciais da Membrana , Capacitação Espermática , Reação Acrossômica/efeitos dos fármacos , Benzoatos/metabolismo , Movimento Celular/efeitos dos fármacos , Cloretos/metabolismo , AMP Cíclico/agonistas , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Humanos , Concentração de Íons de Hidrogênio , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Isoquinolinas/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Capacitação Espermática/efeitos dos fármacos , Sulfonamidas/farmacologia , Tiazolidinas/metabolismo
8.
An Acad Bras Cienc ; 89(3 Suppl): 2053-2073, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28813096

RESUMO

This study aimed to further investigate the cytotoxicity against tumor cell lines and several bacterial strains of Annona squamosa and its mode of action. Methanol extracts of A. squamosa leaves (ASL) and seeds (ASS) were used. ASL showed significant antibacterial activity against S. aureus, K. pneumoniae and E. faecalis with MIC values of 78, 78 and 39 µg/mL respectively. Moreover, ASL exhibited significant biofilm disruption, rapid time dependent kinetics of bacterial killing, increased membrane permeability and significantly reduced the cell numbers and viability. Regarding the cytotoxicity against tumor cell lines, ASS was more active against Jurkat and MCF-7 cells, with CI50 1.1 and 2.1 µg/mL, respectively. ASL showed promising activity against Jurkat and HL60, with CI50 4.2 and 6.4 µg/mL, respectively. Both extracts showed lower activity against VERO cells and reduced the clonogenic survival at higher concentrations (IC90) to MCF-7 and HCT-116 lineages. The alkaloids anonaine, asimilobine, corypalmine, liriodenine nornuciferine and reticuline were identified in extracts by UPLC-ESI-MS/MS analysis. This study reinforced that A. squamosa presents a remarkable phytomedicinal potential and revealed that its antimicrobial mechanism of action is related to bacterial membrane destabilization.


Assuntos
Annona/química , Antibacterianos/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Extratos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Animais , Linhagem Celular Tumoral/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Chlorocebus aethiops , Humanos , Testes de Sensibilidade Microbiana
9.
Rev Med Chil ; 145(8): 987-995, 2017 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-29189856

RESUMO

BACKGROUND: The formal appearance of health care professionals may influence their trustworthiness. AIM: To determine the effect of the orthopedic surgeon's attire on patients' perceptions of credibility and reliability of professionals. MATERIAL AND METHODS: In a cross-sectional design, 351 patients (mean age 43 ± 17 years, 62% males) from the Department of Orthopedics and Traumatology of a Chilean regional hospital in southem of Chile were chosen to complete a questionnaire of attire preferences, in which five photographs with male and female orthopedic surgeons appeared (executive, formal attire, informal attire, scrubs and casual clothing). The influence of attire in the perception of physicians' trustworthiness to resolve medical situations was analyzed. RESULTS: Forty four percent of patients had no physician gender predilection (p = 0.32). Forty three percent of male and 38% of female patients preferred the use of formal attire. In situations of credibility or confidence, all patients chose mostly the use of white coats with formal attire by professionals. The probability of choosing an orthopedic surgeon with a formal attire was significantly higher among patients who considered the attire and appearance of the professional to be very important (Odds ratio = 3.74; p < 0.01). CONCLUSIONS: Patients prefer orthopedic surgeons wearing white coats and formal attire, which improves credibility of these professionals to correctly solve medical situations.


Assuntos
Vestuário/psicologia , Cirurgiões Ortopédicos , Preferência do Paciente/estatística & dados numéricos , Relações Médico-Paciente , Confiança/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Chile , Vestuário/normas , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
10.
Int J Mol Sci ; 17(12)2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27916942

RESUMO

Vernonia polyanthes Less. (Asteraceae), popularly known as "assa-peixe", is a plant species used in Brazilian traditional medicine for the treatment of cutaneous damage, cicatrization, inflammation, and rheumatism. Based on these ethnopharmacological findings, the current study evaluated the topical anti-inflammatory effects of the hexane (HEVP) and ethyl acetate (EAEVP) extracts from V. polyanthes leaves in experimental models of skin inflammation. Chemical characterization was carried out by HPLC-UV/DAD analysis. Anti-inflammatory activity was evaluated using Croton oil-, arachidonic acid (AA)-, phenol-, ethyl phenylpropiolate (EPP)-, and capsaicin-induced ear edema models in mice. Histopathological evaluation and measurements of myeloperoxidase (MPO) and N-acetyl-ß-d-glucosaminidase (NAG) enzymes were also performed. Rutin, luteolin, and apigenin were identified in EAEVP. Topically applied HEVP and EAEVP significantly (p < 0.05, p < 0.01 or p < 0.001) reduced edema induced by five different irritants at the doses tested (0.1, 0.5 and 1.0 mg/ear). Histopathological analysis revealed a reduction of edema, inflammatory cell infiltration, and vasodilation. In addition, the enzymes activity (MPO and NAG) in the ear tissues was reduced by the topical treatment of HEVP and EAEVP (p < 0.05, p < 0.01 or p < 0.001). The results suggest that V. polyanthes leaves are effective against cutaneous damage, which support its traditional use and open up new possibilities for the treatment of skin disorders.


Assuntos
Inflamação/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Pele/efeitos dos fármacos , Vernonia/química , Acetatos/química , Administração Tópica , Animais , Anti-Inflamatórios , Brasil , Hexanos/química , Humanos , Inflamação/patologia , Medicina Tradicional , Camundongos , Fitoterapia , Extratos Vegetais/química , Folhas de Planta/química , Pele/patologia
11.
PLoS Comput Biol ; 10(12): e1003963, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25521294

RESUMO

The primate visual system achieves remarkable visual object recognition performance even in brief presentations, and under changes to object exemplar, geometric transformations, and background variation (a.k.a. core visual object recognition). This remarkable performance is mediated by the representation formed in inferior temporal (IT) cortex. In parallel, recent advances in machine learning have led to ever higher performing models of object recognition using artificial deep neural networks (DNNs). It remains unclear, however, whether the representational performance of DNNs rivals that of the brain. To accurately produce such a comparison, a major difficulty has been a unifying metric that accounts for experimental limitations, such as the amount of noise, the number of neural recording sites, and the number of trials, and computational limitations, such as the complexity of the decoding classifier and the number of classifier training examples. In this work, we perform a direct comparison that corrects for these experimental limitations and computational considerations. As part of our methodology, we propose an extension of "kernel analysis" that measures the generalization accuracy as a function of representational complexity. Our evaluations show that, unlike previous bio-inspired models, the latest DNNs rival the representational performance of IT cortex on this visual object recognition task. Furthermore, we show that models that perform well on measures of representational performance also perform well on measures of representational similarity to IT, and on measures of predicting individual IT multi-unit responses. Whether these DNNs rely on computational mechanisms similar to the primate visual system is yet to be determined, but, unlike all previous bio-inspired models, that possibility cannot be ruled out merely on representational performance grounds.


Assuntos
Modelos Neurológicos , Rede Nervosa/fisiologia , Redes Neurais de Computação , Reconhecimento Visual de Modelos/fisiologia , Lobo Temporal/fisiologia , Algoritmos , Animais , Macaca mulatta , Masculino
12.
An Acad Bras Cienc ; 87(2): 733-42, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26062121

RESUMO

Leishmaniasis is a complex of diseases caused by Leishmania protozoa which treatment is restricted to a limited number of drugs that exhibit high toxicity, collateral effects and are often costly. There are a variety of tropical plants distributed in Brazil, and for many poor people the therapy for several diseases is based mainly on the use of traditional herbal remedies. In this work, the cytotoxic activity of 17 plant methanol extracts was evaluated on several Leishmania species and murine macrophages. Among them, the extract of Casearia sylvestris, Piptocarpha macropoda, Trembleya parviflora, Samanea tubulosa and Plectranthus neochilus showed a promissing leishmanicidal activity, exhibiting IC50 values below of 20 µg/mL against at least one species of Leishmania. Casearia sylvestris showed the most expressive activity against all promastigote forms of Leishmania species (IC50 values of 5.4 µg/mL, 5.0 µg/mL, 8.5 µg/mL and 7.7 µg/mL for L. amazonensis, L. braziliensis, L. chagasi and L. major, respectively), being more effective than the reference drug miltefosine. In spite of the cytotoxic effect on macrophages (CC50 value of 5.2 µg/mL), C. sylvestris exhibited a strong inhibition against intracellular amastigotes of L. braziliensis (IC50 value of 1.3 µg/mL). Further studies, including bio-guided fractionation will be conducted to identify the active compounds.


Assuntos
Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Animais , Brasil , Casearia/química , Concentração Inibidora 50 , Leishmania/classificação , Camundongos , Plantas Medicinais/classificação
13.
Pharm Biol ; 53(12): 1780-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26084799

RESUMO

CONTEXT: Pereskia aculeata Miller (Cactaceae) is a cactus distributed from south to northeast of Brazil, where its leaves are commonly used as a vegetable, in skin wound healing, and to treat inflammation. OBJECTIVES: The objective of this study was to perform the chemical characterization and to evaluate the antinociceptive activity of the hydromethanolic fraction obtained from the methanol extract of P. aculeata leaves. MATERIALS AND METHODS: Chemical characterization was performed by UPLC-MS analysis. The antinociceptive activity was evaluated by the acetic acid-induced writhing, formalin, and tail-flick tests in mice, administering the single oral doses of 100, 200, and 300 mg/kg 1 h before each test. RESULTS: Tryptamine, abrine, mescaline, hordenine, petunidin, di-tert-butylphenol isomers, and quercetin were identified. The antinociceptive activity was inversely proportional to the administered doses in the acetic acid test, as the dose of 100 mg/kg reduced by 78% the number of writhings, while the doses of 200 and 300 mg/kg reduced by 64% and 41%, respectively. In the formalin test, the dose of 300 mg/kg inhibited by 50% and 86% the licking paw time in the first and second phases, respectively, while the doses of 200 mg/kg (45% and 62%, respectively) and 100 mg/kg (15% and 48%, respectively) were less effective. The sample did not respond to the tail-flick test. Those results suggested a peripheral and central antinociception devoid of an opioid effect. CONCLUSION: Pereskia aculeata not only is a plant food with high nutritional value but also presents analgesic potential. It is the first time that this bioactivity is reported for this species.


Assuntos
Analgésicos/farmacologia , Cactaceae , Medição da Dor/efeitos dos fármacos , Extratos Vegetais/farmacologia , Verduras , Analgésicos/isolamento & purificação , Animais , Relação Dose-Resposta a Droga , Masculino , Camundongos , Medição da Dor/métodos , Extratos Vegetais/isolamento & purificação , Folhas de Planta
14.
Glycobiology ; 24(12): 1283-90, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25117007

RESUMO

Abnormal glycosylation is a typical hallmark of the transition from healthy to neoplastic tissues. Although the importance of glycans and glycan-binding proteins in cancer-related processes such as tumor cell adhesion, migration, metastasis and immune escape has been largely appreciated, our awareness of the impact of lectin-glycan recognition in tumor vascularization is relatively new. Regulated glycosylation can influence vascular biology by controlling trafficking, endocytosis and signaling of endothelial cell (EC) receptors including vascular endothelial growth factor receptors, platelet EC adhesion molecule, Notch and integrins. In addition, glycans may control angiogenesis by regulating migration of endothelial tip cells and influencing EC survival and vascular permeability. Recent evidence indicated that changes in the EC surface glycome may also serve "on-and-off" switches that control galectin binding to signaling receptors by displaying or masking-specific glycan epitopes. These glycosylation-dependent lectin-receptor interactions can link tumor hypoxia to EC signaling and control tumor sensitivity to anti-angiogenic treatment.


Assuntos
Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Hipóxia/metabolismo , Neoplasias/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Polissacarídeos/metabolismo , Células Endoteliais/metabolismo , Glicosilação , Humanos , Transdução de Sinais
15.
Plant Foods Hum Nutr ; 69(3): 189-95, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24862084

RESUMO

The exploration of nature as a source of sustainable, novel bioactive substances continues to grow as natural products play a significant role in the search for new therapeutic and agricultural agents. In this context, plants of the genus Pereskia (Cactaceae) have been studied for their biological activities, and are evolving as an interesting subject in the search for new, bioactive compounds. These species are commonly used as human foodstuffs and in traditional medicine to treat a variety of diseases. This review focuses on the bioactivity and chemical composition of the genus Pereskia, and aims to stimulate further studies on the chemistry and biological potential of the genus.


Assuntos
Cactaceae/química , Extratos Vegetais/farmacologia , Analgésicos/química , Analgésicos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Cactaceae/classificação , Diuréticos/química , Diuréticos/farmacologia , Humanos , Extratos Vegetais/química , Folhas de Planta/química , Especiarias/análise
16.
Cell Death Differ ; 30(4): 906-921, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36693903

RESUMO

Non-melanoma skin cancer (NMSC) has risen dramatically as a result of chronic exposure to sunlight ultraviolet (UV) radiation, climatic changes and clinical conditions associated with immunosuppression. In spite of considerable progress, our understanding of the mechanisms that control NMSC development and their associated molecular and immunological landscapes is still limited. Here we demonstrated a critical role for galectin-7 (Gal-7), a ß-galactoside-binding protein preferentially expressed in skin tissue, during NMSC development. Transgenic mice (Tg46) overexpressing Gal-7 in keratinocytes showed higher number of papillomas compared to WT mice or mice lacking Gal-7 (Lgals7-/-) when subjected to a skin carcinogenesis protocol, in which tumor initiator 7,12-dimethylbenz[a]anthracene (DMBA) and tumor promoter 12-O-tetradecanoyl-phorbol-13-acetate (TPA) were sequentially administered. RNAseq analysis of Tg46 tumor lesions revealed a unique profile compatible with cells of the myelomonocytic lineage infiltrating these tumors, an effect that was substantiated by a higher number of CD11b+Gr1+ cells in tumor-draining lymph nodes. Heightened c-Met activation and Cxcl-1 expression in Tg46 lesions suggested a contribution of this pathway to the recruitment of these cells. Remarkably, Gal-7 bound to the surface of CD11b+Ly6ChiLy6Glo monocytic myeloid cells and enhanced their immunosuppressive activity, as evidenced by increased IL-10 and TGF-ß1 secretion, and higher T-cell inhibitory activity. In vivo, carcinogen-treated Lgals7-/- animals adoptively transferred with Gal-7-conditioned monocytic myeloid cells developed higher number of papillomas, whereas depletion of these cells in Tg46-treated mice led to reduction in the number of tumors. Finally, human NMSC biopsies showed increased LGALS7 mRNA and Gal-7 protein expression and displayed transcriptional profiles associated with myeloid programs, accompanied by elevated CXCL1 expression and c-Met activation. Thus, Gal-7 emerges as a critical mediator of skin carcinogenesis and a potential therapeutic target in human NMSC.


Assuntos
Papiloma , Neoplasias Cutâneas , Camundongos , Animais , Humanos , Carcinógenos , Neoplasias Cutâneas/patologia , Papiloma/patologia , Carcinogênese/genética , Camundongos Transgênicos , Galectinas/genética , Pele/metabolismo , Imunidade Inata
17.
J Ethnopharmacol ; 265: 113344, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32890711

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Siparuna guianensis Aublet leaves, known as negramina, are used by indigenous and local communities in Brazil and other countries in the Americas to treat pain and inflammatory diseases. AIM OF THE STUDY: To characterize the chemical constituents and to evaluate the antioxidant, anti-inflammatory, antinociceptive and locomotor activities of the dichloromethane fraction (DF) of S. guianensis leaves. Also, an acute oral toxicity test was accomplished. MATERIAL AND METHODS: The chemical characterization of DF was performed by ultra-high pressure liquid chromatography (UHPLC) analyses coupled with a high-resolution mass spectrometer. The antioxidant potential of DF was investigated using nitric oxide (NO) and hydroxyl radical (OH) scavenging test. The evaluation study of the anti-inflammatory activity was carried out in vitro by NO measurement in stimulated macrophages and, in vivo, by croton oil-induced ear edema, LPS-induced peritonitis, and zymosan-induced arthritis in mice. Different mechanisms of central and peripheral nociception were stimulated by acetic acid-induced writhing, formalin, and tail-flick tests. Besides that, the open field assay was performed. RESULTS: UHPLC analyses of DF showed the presence of a mixture of glycosylated and methoxylated flavonoids. DF was able to scavenge NO and OH radicals in vitro and showed anti-inflammatory activity by inhibiting NO production in LPS-stimulated murine macrophages. Oral administration of DF considerably inhibited the ear edema after croton oil application and reduced the leukocyte infiltrated in LPS-induced peritonitis. In the inflammatory intra-articular zymosan-induced process, DF showed a significant reduction in the inflammatory area and of the cells in the synovial and connective tissues adjacent to the joint. Also, DF was able to reduce the intra-articular edema. In nociception models, the oral administration of DF considerably inhibited the acetic acid-induced writhings. The formalin test showed that DF attenuated the licking time in both phases, which suggested that DF reduce the nociception by central and peripheral mechanisms. In the tail-flick test, DF showed no activity. Besides that, DF did not affect the animal locomotion, and no acute toxicity was observed. CONCLUSIONS: For the first time, the anti-inflammatory and antinociceptive activities of S. guianensis were reported, supporting its ethnopharmacological uses for some inflammatory diseases and painful conditions.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios/farmacologia , Laurales/química , Extratos Vegetais/farmacologia , Analgésicos/isolamento & purificação , Animais , Anti-Inflamatórios/isolamento & purificação , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Brasil , Modelos Animais de Doenças , Edema/tratamento farmacológico , Locomoção/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Masculino , Medicina Tradicional , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/metabolismo , Nociceptividade/efeitos dos fármacos , Dor/tratamento farmacológico , Medição da Dor
18.
PLoS Comput Biol ; 5(11): e1000579, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19956750

RESUMO

While many models of biological object recognition share a common set of "broad-stroke" properties, the performance of any one model depends strongly on the choice of parameters in a particular instantiation of that model--e.g., the number of units per layer, the size of pooling kernels, exponents in normalization operations, etc. Since the number of such parameters (explicit or implicit) is typically large and the computational cost of evaluating one particular parameter set is high, the space of possible model instantiations goes largely unexplored. Thus, when a model fails to approach the abilities of biological visual systems, we are left uncertain whether this failure is because we are missing a fundamental idea or because the correct "parts" have not been tuned correctly, assembled at sufficient scale, or provided with enough training. Here, we present a high-throughput approach to the exploration of such parameter sets, leveraging recent advances in stream processing hardware (high-end NVIDIA graphic cards and the PlayStation 3's IBM Cell Processor). In analogy to high-throughput screening approaches in molecular biology and genetics, we explored thousands of potential network architectures and parameter instantiations, screening those that show promising object recognition performance for further analysis. We show that this approach can yield significant, reproducible gains in performance across an array of basic object recognition tasks, consistently outperforming a variety of state-of-the-art purpose-built vision systems from the literature. As the scale of available computational power continues to expand, we argue that this approach has the potential to greatly accelerate progress in both artificial vision and our understanding of the computational underpinning of biological vision.


Assuntos
Algoritmos , Inteligência Artificial , Biomimética/métodos , Modelos Neurológicos , Reconhecimento Automatizado de Padrão/métodos , Reconhecimento Visual de Modelos/fisiologia , Córtex Visual/fisiologia , Animais , Simulação por Computador , Humanos
19.
Front Microbiol ; 11: 1525, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32733416

RESUMO

Candida tropicalis is one the most relevant biofilm-forming fungal species increasingly associated with invasive mucosal candidiasis worldwide. The amplified antifungal resistance supports the necessity for more effective and less toxic treatment, including the use of plant-derived natural products. Scopoletin, a natural coumarin, has shown antifungal properties against plant yeast pathogens. However, the antifungal activity of this coumarin against clinically relevant fungal species such as C. tropicalis remains to be established. Here, we investigated the potential antifungal properties and mechanisms of action of scopoletin against a multidrug-resistant C. tropicalis strain (ATCC 28707). First, scopoletin was isolated by high-performance liquid chromatography from Mitracarpus frigidus, a plant species (family Rubiaceae) distributed throughout South America. Next, scopoletin was tested on C. tropicalis cultivated for 48h in both planktonic and biofilm forms. Fungal planktonic growth inhibition was analyzed by evaluating minimal inhibitory concentration (MIC), time-kill kinetics and cell density whereas the mechanisms of action were investigated with nucleotide leakage, efflux pumps and sorbitol and ergosterol bioassays. Finally, the scopoletin ability to affect C. tropicalis biofilms was evaluated through spectrophotometric and whole slide imaging approaches. In all procedures, fluconazole was used as a positive control. MIC values for scopoletin and fluconazole were 50 and 250 µg/L respectively, thus demonstrating a fungistatic activity for scopoletin. Scopoletin induced a significant decrease of C. tropicalis growth curves and cell density (91.7% reduction) compared to the growth control. Its action was related to the fungal cell wall, affecting plasma membrane sterols. When associated with fluconazole, scopoletin led to inhibition of efflux pumps at the plasma membrane. Moreover, scopoletin not only inhibited the growth rate of preformed biofilms (68.2% inhibition at MIC value) but also significantly decreased the extent of biofilms growing on the surface of coverslips, preventing the formation of elongated fungal forms. Our data demonstrate, for the first time, that scopoletin act as an effective antifungal phytocompound against a multidrug-resistant strain of C. tropicalis with properties that affect both planktonic and biofilm forms of this pathogen. Thus, the present findings support additional studies for antifungal drug development based on plant isolated-scopoletin to treat candidiasis caused by C. tropicalis.

20.
J Pharm Pharmacol ; 72(12): 1933-1945, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32846458

RESUMO

OBJECTIVES: A previous study reported that the hexane fraction (HF) obtained from Pereskia aculeata leaves showed promising topical anti-inflammatory activity. Intending its future use in clinical practice, a herbal medicine cream named INFLATIV was developed. Its anti-inflammatory and antipsoriatic potential were investigated. INFLATIV was subjected to preliminary accelerated stability tests and to a degradation profile assessment. METHODS: INFLATIV was prepared at 6% and 12%. The anti-inflammatory activity was assessed by croton oil single and multiple application challenge in mice. Mouse tail test was used for antipsoriatic potential investigation. Cutaneous atrophy test was performed. Preliminary accelerated stability tests were performed together with a degradation profile by GC-MS analysis. KEY FINDINGS: The anti-inflammatory activity shown by INFLATIV was comparable to dexamethasone. However, the skin atrophy caused by that drug was not observed. INFLATIV modified skin parakeratotic differentiation into orthokeratosis, which revealed its antipsoriatic potential. The ingredients used were suitable to carry the bioactives as they were well permeated by the skin. The preliminary accelerated stability tests indicated that INFLATIV 6% is more stable than 12%. CONCLUSIONS: The results demonstrated the relevant therapeutic and marketing potentials of INFLATIV, which is likely to be further evaluated in clinical trials for drug registration process with regulatory agencies.


Assuntos
Anti-Inflamatórios/administração & dosagem , Cactaceae , Edema/prevenção & controle , Extratos Vegetais/administração & dosagem , Psoríase/tratamento farmacológico , Pele/efeitos dos fármacos , Administração Cutânea , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/metabolismo , Cactaceae/química , Óleo de Cróton , Modelos Animais de Doenças , Edema/induzido quimicamente , Edema/metabolismo , Edema/patologia , Masculino , Camundongos , Permeabilidade , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Folhas de Planta , Psoríase/metabolismo , Psoríase/patologia , Pele/metabolismo , Pele/patologia , Absorção Cutânea , Creme para a Pele
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