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1.
Arch Biochem Biophys ; 753: 109884, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38218361

RESUMO

The spread of fungi resistant to conventional drugs has become a threatening problem. In this context, antimicrobial peptides (AMPs) have been considered as one of the main alternatives for controlling fungal infections. Here, we report the antifungal and antibiofilm activity and some clues about peptide RQ18's mechanism of action against Candida and Cryptococcus. This peptide inhibited yeast growth from 2.5 µM and killed all Candida tropicalis cells within 2 h incubation. Moreover, it showed a synergistic effect with antifungal agent the amphotericin b. RQ18 reduced biofilm formation and promoted C. tropicalis mature biofilms eradication. RQ18's mechanism of action involves fungal cell membrane damage, which was confirmed by the results of RQ18 in the presence of free ergosterol in the medium and fluorescence microscopy by Sytox green. No toxic effects were observed in murine macrophage cell lines and Galleria mellonella larvae, suggesting fungal target selectivity. Therefore, peptide RQ18 represents a promising strategy as a dual antifungal and antibiofilm agent that contributes to infection control without damaging mammalian cells.


Assuntos
Anfotericina B , Antifúngicos , Animais , Camundongos , Antifúngicos/farmacologia , Anfotericina B/farmacologia , Peptídeos/farmacologia , Candida tropicalis , Biofilmes , Testes de Sensibilidade Microbiana , Mamíferos
2.
Molecules ; 28(19)2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37836787

RESUMO

IR-780 is a fluorescent marker, photostable and non-toxic, and is widely used in tumor targeting; however, studies on the impact of IR-780 in animal models of B16-F10 melanoma are scarce in the literature. Therefore, this study aims to analyze behavior of this marker in melanoma cells using in vitro and in vivo analyses with fluorescence microscopy to conduct an analysis of cell culture, and an in vivo imaging system for an analysis of cell culture, tumor targeting on animals, and organ examination. In vitro analysis showed that B16-F10 cells at a concentration of 2 × 105 cells.plate-1 allowed a better visualization using 20 µM of IR-780. Furthermore, the location of IR-780 accumulation was confirmed by its fluorescence microscopy. Through in vivo studies, fluorescence was not observed in subcutaneous nodules, and it was found that animals that received intraperitoneal injection of B16-F10 cells presented ascites and did not absorb IR-780. Additionally, animals exhibiting lung metastasis showed fluorescence in ex vivo lung images. Therefore, use of the IR-780 marker for evaluating the progression of tumor growth did not demonstrate efficiency; however, it was effective in diagnosing pulmonary metastatic tumors. Although this marker presented limitations, results of evaluating pulmonary involvement through ex vivo fluorescence imaging were determined based on intensity of fluorescence.


Assuntos
Neoplasias Pulmonares , Melanoma Experimental , Neoplasias Cutâneas , Animais , Camundongos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/secundário , Melanoma Experimental/diagnóstico por imagem , Melanoma Experimental/patologia , Pulmão/patologia , Camundongos Endogâmicos C57BL
3.
Biofouling ; 36(5): 516-527, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32619153

RESUMO

Candida yeast infections are the fourth leading cause of death worldwide. Peptides with antimicrobial activity are a promising alternative treatment for such infections. Here, the antifungal activity of a new antimicrobial peptide-PEP-IA18-was evaluated against Candida species. PEP-IA18 was designed from the primary sequence of profilin, a protein from Spodoptera frugiperda, and displayed potent activity against Candida albicans and Candida tropicalis, showing a minimum inhibitory concentration (MIC) of 2.5 µM. Furthermore, the mechanism of action of PEP-IA18 involved interaction with the cell membrane (ergosterol complexation). Treatment at MIC and/or 10 × MIC significantly reduced biofilm formation and viability. PEP-IA18 showed low toxicity toward human fibroblasts and only revealed hemolytic activity at high concentrations. Thus, PEP-IA18 exhibited antifungal and anti-biofilm properties with potential applicability in the treatment of infections caused by Candida species.


Assuntos
Antifúngicos/farmacologia , Biofilmes , Candida , Profilinas/farmacologia , Spodoptera/microbiologia , Animais , Candida albicans , Humanos , Testes de Sensibilidade Microbiana , Peptídeos
4.
Arch Microbiol ; 201(2): 223-233, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30483842

RESUMO

We describe the characterization of IETI, the first trypsin inhibitor purified from Inga edulis, a tree widely distributed in Brazil. Two-step chromatography was used to purify IETI, a protein composed of a single peptide chain of 19,685.10 Da. Amino-terminal sequencing revealed that IETI shows homology with the Kunitz family, as substantiated by its physical-chemical features, such as its thermal (up to 70 °C) and wide-range pH stability (from 2 to 10), and the value of its dissociation constant (6.2 nM). IETI contains a single reactive site for trypsin, maintained by a disulfide bridge; in the presence of DTT, its inhibitory activity was reduced in a time- and concentration-dependent manner. IETI presented activity against Candida ssp., including C. buinensis and C. tropicalis. IETI inhibitory activity triggered yeast membrane permeability, affecting cell viability, thus providing support for the use of IETI in further studies for the control of fungal infections.


Assuntos
Antifúngicos/química , Candida/efeitos dos fármacos , Fabaceae/química , Proteínas de Plantas/química , Inibidores da Tripsina/química , Sequência de Aminoácidos , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Brasil , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/farmacologia , Sementes/química , Inibidores da Tripsina/isolamento & purificação , Inibidores da Tripsina/farmacologia
5.
Molecules ; 24(23)2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31795088

RESUMO

The Indianmeal moth, Plodia interpunctella, is one of the most damaging pests of stored products. We investigated the insecticidal properties of ApKTI, a Kunitz trypsin inhibitor from Adenanthera pavonina seeds, against P. interpunctella larvae through bioassays with artificial diet. ApKTI-fed larvae showed reduction of up to 88% on larval weight and 75% in survival. Trypsin enzymes extracted from P. interpunctella larvae were inhibited by ApKTI, which also demonstrated capacity to bind to chitin. Kinetic studies revealed a non-competitive inhibition mechanism of ApKTI for trypsin, which were further corroborated by molecular docking studies. Furthermore, we have demonstrated that ApKTI exhibits a hydrophobic pocket near the reactive site loop probably involved in chitin interactions. Taken together, these data suggested that the insecticidal activity of ApKTI for P. interpunctella larvae involves a dual and promiscuous mechanisms biding to two completely different targets. Both processes might impair the P. interpunctella larval digestive process, leading to larvae death before reaching the pupal stage. Further studies are encouraged using ApKTI as a biotechnological tool to control insect pests in field conditions.


Assuntos
Fabaceae/química , Inseticidas/química , Inseticidas/farmacologia , Mariposas/efeitos dos fármacos , Inibidores da Tripsina/química , Inibidores da Tripsina/farmacologia , Animais , Biomassa , Quitina , Inseticidas/isolamento & purificação , Larva , Modelos Moleculares , Conformação Proteica , Sementes/química , Relação Estrutura-Atividade , Tripsina/química , Inibidores da Tripsina/isolamento & purificação
6.
Artigo em Inglês | MEDLINE | ID: mdl-28660700

RESUMO

Plant protease inhibitors (PIs) are elements of a common plant defense mechanism induced in response to herbivores. The fall armyworm, Spodoptera frugiperda, a highly polyphagous lepidopteran pest, responds to various PIs in its diet by expressing genes encoding trypsins. This raises the question of whether the PI-induced trypsins are also inhibited by other PIs, which we posed as the hypothesis that Inga laurina trypsin inhibitor (ILTI) inhibits PI-induced trypsins in S. frugiperda. In the process of testing our hypothesis, we compared its properties with those of selected PIs, soybean Kunitz trypsin inhibitor (SKTI), Inga vera trypsin inhibitor (IVTI), Adenanthera pavonina trypsin inhibitor (ApTI), and Entada acaciifolia trypsin inhibitor (EATI). We report that ILTI is more effective in inhibiting the induced S. frugiperda trypsins than SKTI and the other PIs, which supports our hypothesis. ILTI may be more appropriate than SKTI for studies regarding adaptive mechanisms to dietary PIs.


Assuntos
Fabaceae/química , Controle de Insetos , Proteínas de Insetos/antagonistas & inibidores , Spodoptera/enzimologia , Inibidores da Tripsina/química , Animais , Proteínas de Insetos/isolamento & purificação , Larva , Inibidor da Tripsina de Soja de Kunitz , Inibidores da Tripsina/isolamento & purificação
7.
Pestic Biochem Physiol ; 142: 67-76, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29107249

RESUMO

Biotechnological techniques allow the investigation of alternatives to outdated chemical insecticides for crop protection; some investigations have focused on the identification of molecules tailored from nature for this purpose. We, herein, describe the negative effects of water-soluble lectin from Moringa oleifera seeds (WSMoL) on Anagasta kuehniella development. The chitin-binding lectin, WSMoL, impaired the larval weight gain by 50% and affected the activity of the pest's major digestive enzymes. The commitment of the digestive process became evident after controlled digestion studies, where the capacity of protein digestion was compromised by >90%. Upon acute exposure, the lectin was not resistant to digestion; however, chronic ingestion of WSMoL was able to reverse this feature. Thus, we show that resistance to digestion may not be a prerequisite for a lectin's ability to exert negative effects on larval physiology. The mechanism of action of WSMoL involves binding to chitin with possible disruption to the peritrophic membrane, causing disorder between the endo- and ectoperitrophic spaces. Additionally, results suggest that WSMoL may trigger apoptosis in gut cells, leading to the lower enzymatic activity observed in WSMoL-fed larvae. Although assays employing an artificial diet did not demonstrate effects of WSMoL on A. kuehniella mortality, this lectin may hold potential for exerting insecticide effects on other pest insects, as well for use in other experimental approaches, such as WSMoL-expressing plants. Moreover, the use of WSMoL with other biotechnological tools, such as 'pyramid' crops, may represent a strategy for delaying the evolution of pest resistance to transgenic crops, since its multiple site targets could act in synergism with other insecticide compounds.


Assuntos
Inseticidas/farmacologia , Lectinas/farmacologia , Moringa oleifera/química , Mariposas/fisiologia , Animais , Quitina/química , Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Inseticidas/química , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/fisiologia , Lectinas/química , Mariposas/efeitos dos fármacos , Mariposas/crescimento & desenvolvimento , Sementes/química
8.
Pestic Biochem Physiol ; 118: 1-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25752423

RESUMO

This paper describes the characterization of a trypsin inhibitor from Poincianella pyramidalis seeds (PpyTI). The partial sequencing of PpyTI revealed homology to Kunitz inhibitors, clustered as a member of Family I03 in MEROPS database. PpyTI has a single polypeptide chain of 19,042 Da and presents stability at high temperatures (up to 70 °C) and a wide range of pH. In vitro assays showed that disulfide bridges have an important stabilization role of reactive site in PpyTI, a characteristic shared among several Kunitz inhibitors. Bioassays carried out with the Mediterranean flour moth (Anagasta kuehniella) revealed a significant decrease in both larval weight and survival of PpyTI-fed larvae, besides a larval stage extension. Through biochemical analysis, we demonstrated that the PpyTI insecticide effects were triggered by digestion process commitment, through the inhibition of trypsin and chymotrypsin activities, the major digestive enzymes in this species. The insecticide effects and biochemical characterization of PpyTI encourage further studies using this inhibitor for insect pest control.


Assuntos
Fabaceae/química , Inseticidas/isolamento & purificação , Inseticidas/farmacologia , Mariposas/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Inibidores da Tripsina/isolamento & purificação , Inibidores da Tripsina/farmacologia , Sequência de Aminoácidos , Animais , Digestão , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/enzimologia , Trato Gastrointestinal/fisiologia , Proteínas de Insetos/antagonistas & inibidores , Proteínas de Insetos/metabolismo , Inseticidas/química , Dados de Sequência Molecular , Mariposas/enzimologia , Extratos Vegetais/química , Alinhamento de Sequência , Inibidores da Tripsina/química
9.
Pestic Biochem Physiol ; 108: 74-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24485318

RESUMO

The Mediterranean flour moth (Anagasta kuehniella) is a pest insect that attacks stored foods. The difficulty in controlling this kind of pest promotes the development of alternatives for pest control, among them the use of proteins with insecticide effect. In this work, we evaluated the role of a trypsin inhibitor purified from Entada acaciifolia seeds (EATI) on the A. kuehniella development. Different concentrations of inhibitor were added to a diet to determine its effects on insect performance. At 0.4%, the EATI decreases the larval weight and survival rates by 54.6% and 15%, respectively; in addition to the extension of the life cycle of insect. The biochemical analysis showed that the inhibitor is refractory to the digestion by midgut proteases, and led to a reduction of 32% in general proteolytic activity. A detailed analysis of the enzymatic activity revealed a decrease of 50% in trypsin activity as the chymotrypsin activity increased by 12%; possibly to compensate the commitment of the digestive process. The trypsins from the EATI-fed group stayed sensitive to the inhibition by EATI, and based on kinetic assays no new trypsin enzymes were produced as adaptation attempt. The insecticides effects observed for the EATI against this pest encourage a more in depth study of its possible long-term use as a biotechnological tool.


Assuntos
Fabaceae/química , Mariposas/efeitos dos fármacos , Mariposas/crescimento & desenvolvimento , Extratos Vegetais/farmacologia , Inibidores da Tripsina/farmacologia , Animais , Proteínas de Insetos/antagonistas & inibidores , Proteínas de Insetos/metabolismo , Estágios do Ciclo de Vida/efeitos dos fármacos , Mariposas/enzimologia , Sementes/química , Tripsina/metabolismo
10.
Biochimie ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39029576

RESUMO

Bacterial resistance has become a serious public health problem in recent years, thus encouraging the search for new antimicrobial agents. Here, we report an antimicrobial peptide (AMP), called PEPAD, which was designed based on an encrypted peptide from a Kunitz-type plant peptidase inhibitor. PEPAD was capable of rapidly inhibiting and eliminating numerous bacterial species at micromolar concentrations (from 4 µM to 10 µM), with direct membrane activity. It was also observed that the peptide can act synergistically with ciprofloxacin and showed no toxicity in the G. mellonella in vivo assay. Circular dichroism assays revealed that the peptide's secondary structure adopts different scaffolds depending on the environment in which it is inserted. In lipids mimicking bacterial cell membranes, PEPAD adopts a more stable α-helical structure, which is consistent with its membrane-associated mechanism of action. When in contact with lipids mimicking mammalian cells, PEPAD adopts a disordered structure, losing its function and suggesting cellular selectivity. Therefore, these findings make PEPAD a promising candidate for future antimicrobial therapies with low toxicity to the host.

11.
Nat Prod Res ; : 1-7, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963903

RESUMO

Mangaba is a fruit native to Brazil, rich in bioactive compounds. To evaluate physicochemical composition, bioactive compounds, antioxidant and antifungal activity of mangaba fruit pulp. Moisture, ash, protein, lipid, energy values and phenolic compounds were determined. Antioxidant activity was determined by capture of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. Evaluation of antifungal activity was performed by Minimum Inhibitory Concentration, according to protocols M07-A9 and M27-S3, and minimum fungicidal concentration. Freeze-dried mangaba pulp presented high levels of carbohydrates, low levels of lipids, and high energy density. Phenolic analysis demonstrated that chlorogenic acid was found in the highest concentration, followed by p-coumaric acid and ferulic acid. Mangaba extract showed antioxidant activity like BHT. Mangaba extract inhibited the growth of Candida albicans (ATCC 90028), Cryptococcus gattii (AFLP4), Candida guilliermondii (ATCC 6260) and Candida albicans (MYA 2876). Freeze-dried mangaba inhibited fungal activity associated with antioxidant effect due to presence of phenolic compounds.

12.
Toxins (Basel) ; 15(1)2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36668862

RESUMO

In recent years, antimicrobial peptides isolated from amphibian toxins have gained attention as new multifunctional drugs interacting with different molecular targets. We aimed to rationally design a new peptide from temporin-PTa. Hp-MAP3 (NH2-LLKKVLALLKKVL-COOH), net charge (+4), hydrophobicity (0.69), the content of hydrophobic residues (69%), and hydrophobic moment (0.73). For the construction of the analog peptide, the physicochemical characteristics were reorganized into hydrophilic and hydrophobic residues with the addition of lysines and leucines. The minimum inhibitory concentration was 2.7 to 43 µM against the growth of Gram-negative and positive bacteria, and the potential for biofilm eradication was 173.2 µM. Within 20 min, the peptide Hp-MAP3 (10.8 µM) prompted 100% of the damage to E. coli cells. At 43.3 µM, eliminated 100% of S. aureus within 5 min. The effects against yeast species of the Candida genus ranged from 5.4 to 86.6 µM. Hp-MAP3 presents cytotoxic activity against tumor HeLa at a concentration of 21.6 µM with an IC50 of 10.4 µM. Furthermore, the peptide showed hemolytic activity against murine erythrocytes. Structural studies carried out by circular dichroism showed that Hp-MAP3, while in the presence of 50% trifluoroethanol or SDS, an α-helix secondary structure. Finally, Amphipathic Hp-MAP3 building an important model for the design of new multifunctional molecules.


Assuntos
Proteínas de Anfíbios , Peptídeos Catiônicos Antimicrobianos , Animais , Humanos , Camundongos , Sequência de Aminoácidos , Proteínas de Anfíbios/química , Proteínas de Anfíbios/farmacologia , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Dicroísmo Circular , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Ranidae , Staphylococcus aureus/efeitos dos fármacos
13.
Pharmaceuticals (Basel) ; 15(6)2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35745643

RESUMO

Nature presents a wide range of biomolecules with pharmacological potential, including venomous animal proteins. Among the protein components from snake venoms, phospholipases (PLA2) are of great importance for the development of new anticancer compounds. Thus, we aimed to evaluate the PLA2 anticancer properties from Bothrops moojeni venom. The crude venom was purified through three chromatographic steps, monitored by enzymatic activity and SDS-PAGE (12%). The purified PLA2 denominated BmPLA2 had its molecular mass and N-terminal sequence identified by mass spectrometry and Edman degradation, respectively. BmPLA2 was assayed against human epithelial colorectal adenocarcinoma cells (Caco-2), human rhabdomyosarcoma cells (RD) and mucoepidermoid carcinoma of the lung (NCI-H292), using human fibroblast cells (MRC-5) and microglia cells (BV-2) as a cytotoxicity control. BmPLA2 presented 13,836 Da and a 24 amino acid-residue homologue with snake PLA2, which showed a 90% similarity with other Bothrops moojeni PLA2. BmPLA2 displayed an IC50 of 0.6 µM against Caco-2, and demonstrated a selectivity index of 1.85 (compared to MRC-5) and 6.33 (compared to BV-2), supporting its selectivity for cancer cells. In conclusion, we describe a new acidic phospholipase, which showed antitumor activity and is a potential candidate in the development of new biotechnological tools.

14.
Biochim Biophys Acta Gen Subj ; 1866(12): 130244, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36162730

RESUMO

Antimicrobial peptides (AMPs) are promising tools for developing new antibiotics. We described the design of IKR18, an AMP designed with the aid of computational tools. IKR18 showed antimicrobial activity against Gram-negative and Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). CD studies revealed that IKR18 assumes an alpha-helical structure in the membrane-mimetic environment. The action mechanism IKR18 involves damage to the bacteria membrane, as demonstrated by Sytox green uptake. Furthermore, IKR18 displayed synergic and additive effects in combination with antibiotics ciprofloxacin and vancomycin. The peptide showed anti-biofilm activity in concentration and efficiency compared with commercial antibiotics, involving the direct death of bacteria, as confirmed by scanning electron microscopy. The anti-infective activity of IKR18 was demonstrated in the Galleria mellonella model infected with S. aureus, MRSA, and Acinetobacter baumannii. The novel bioinspired peptide, IKR18, proved to be effective in the control of bacterial infection, opening opportunities for the development of further assays, including preclinical models.


Assuntos
Anti-Infecciosos , Staphylococcus aureus Resistente à Meticilina , Mariposas , Animais , Peptídeos Antimicrobianos , Staphylococcus aureus , Testes de Sensibilidade Microbiana , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias
15.
Biomed Pharmacother ; 144: 112198, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34656058

RESUMO

Erythrina poeppigiana belongs to Fabaceae family (subfamily Papillionoideae) and is commonly found in tropical and subtropical regions in Brazil. Herein, we described the purification and characterization of a new Kunitz-type inhibitor, obtained from E. poeppigiana seeds (EpTI). EpTI is composed by three isoforms of identical amino-terminal sequences with a molecular weight ranging from 17 to 20 kDa. The physicochemical features showed by EpTI are common to Kunitz inhibitors, including the dissociation constant (13.1 nM), stability against thermal (37-100 °C) and pH (2-10) ranging, and the presence of disulfide bonds stabilizing its reactive site. Furthermore, we investigated the antimicrobial, anti-adhesion, and anti-biofilm properties of EpTI against Gram-positive and negative bacteria. The inhibitor showed antimicrobial activity with a minimum inhibitory concentration (MIC, 5-10 µM) and minimum bactericidal concentration (MBC) of 10 µM for Enterobacter aerogenes, Enterobacter cloacae, Klebsiella pneumoniae, Staphylococcus aureus, and Staphylococcus haemolyticus. The combination of EpTI with ciprofloxacin showed a marked synergistic effect, reducing the antibiotic concentration by 150%. The increase in crystal violet uptake for S. aureus and K. pneumoniae strains was approximately 30% and 50%, respectively, suggesting that the bacteria plasma membrane is targeted by EpTI. Treatment with EpTI at 1x and 10 x MIC significantly reduced the biofilm formation and prompted the disruption of a mature biofilm. At MIC/2, EpTI decreased the bacterial adhesion to polystyrene surface within 2 h. Finally, EpTI showed low toxicity in animal model Galleria mellonella. Given its antimicrobial and anti-biofilm properties, the EpTI sequence might be used to design novel drug prototypes.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Erythrina , Extratos Vegetais/farmacologia , Inibidores da Tripsina/farmacologia , Animais , Antibacterianos/isolamento & purificação , Antibacterianos/toxicidade , Bactérias/crescimento & desenvolvimento , Biofilmes/crescimento & desenvolvimento , Ciprofloxacina/farmacologia , Sinergismo Farmacológico , Erythrina/química , Testes de Sensibilidade Microbiana , Mariposas/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Sementes , Inibidores da Tripsina/isolamento & purificação , Inibidores da Tripsina/toxicidade
16.
PLoS One ; 16(4): e0249919, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33914744

RESUMO

Zootherapy is a traditional secular practice among the Guarani-Kaiowá indigenous ethnic group living in Mato Grosso do Sul, Brazil. My people use the oil extracted from larvae of the snout beetle Rhynchophorus palmarum (Linnaeus, 1758) to treat and heal skin wounds and respiratory diseases. Based on this ethnopharmacological knowledge, the chemical composition and antioxidant, antimicrobial, and healing properties of R. palmarum larvae oil (RPLO) were investigated, as well as possible toxic effects, through in vitro and in vivo assays. The chemical composition of the RPLO was determined using gas chromatography coupled with mass spectrometry. The antioxidant activity of RPLO was investigated through the direct 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, and the antimicrobial activity was evaluated against Gram-positive and Gram-negative bacteria that are pathogenic to humans. The healing properties of RPLO were investigated by performing a cell migration assay using human lung fibroblasts (MRC-5), and the toxicity was analyzed, in vivo, using a Caenorhabditis elegans model and MRC-5 cells, in vitro. RPLO contains 52.2% saturated fatty acids and 47.4% unsaturated fatty acids, with palmitic acid (42.7%) and oleic acid (40%) representing its major components, respectively. RPLO possesses direct antioxidant activity, with a half-maximal inhibitory concentration (IC50) of 46.15 mg.ml-1. The antimicrobial activity of RPLO was not observed at a concentration of 1% (v/v). RPLO did not alter the viability of MRC-5 cells and did not exert toxic effects on C. elegans. Furthermore, MRC-5 cells incubated with 0.5% RPLO showed a higher rate of cell migration than that of the control group, supporting its healing properties. Taken together, RPLO possesses direct antioxidant activity and the potential to aid in the healing process and is not toxic toward in vitro and in vivo models, corroborating the safe use of the oil in traditional Guarani-Kaiowá medicine.


Assuntos
Besouros/metabolismo , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Óleos Voláteis/farmacologia , Animais , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Antioxidantes/química , Caenorhabditis elegans/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Besouros/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Larva/química , Larva/metabolismo , Testes de Sensibilidade Microbiana , Óleos Voláteis/análise , Óleos Voláteis/química
17.
Braz J Microbiol ; 41(2): 278-82, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24031491

RESUMO

The emergence of Extended-Spectrum Beta-Lactamase (ESBL)-producing microorganisms in Brazilian hospitals is a challenge that concerns scientists, clinicians and healthcare institutions due to the serious risk they pose to confined patients. The goal of this study was the detection of ESBL production by clinical strains of Escherichia coli and Klebsiella sp. isolated from pus, urine and blood of patients at Hospital Universitário Santa Maria, Rio Grande Sul, RS, Brazil and the genotyping of the isolates based on bla SHV genes. The ESBL study was carried out using the Combined Disc Method, while Polymerase Chain Reaction (PCR) was used to study the bla SHV genes. Of the 90 tested isolates, 55 (61.1%) were identified as ESBL-producing by the combined disk method. The bla SHV genes were found in 67.8% of these microorganisms. K. pneumoniae predominated in the samples, presenting the highest frequency of positive results from the combined disk and PCR.

18.
Rev Bras Med Trab ; 18(2): 149-157, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33324456

RESUMO

BACKGROUND: The dental surgeon and dental health assistant experience risk situations and must be prepared for the prevention of diseases and accidents at work. OBJECTIVE: Evaluating the prevalence of occupational infectious diseases and prevention measures used by the DS and dental health assistants. METHODS: Cross-sectional study carried out with professionals working at the Northwestern region of Rio Grande do Sul. We carried out an interview using a structured questionnaire containing variables related to sociodemographic factors and prevention of infectious diseases. Subjects were submitted to blood collection for serological test for infectious diseases. RESULTS: The use of goggles and cap was higher among the dental health assistant. The dental surgeon reported frequent use of mask: 45.5% replaced the used mask at each new patient. All participants reported using gloves and changing them for each new patient. 78.3% of workers have attended patients with infectious diseases. Among professionals evaluated, dental surgeons reported the highest number of accidents with needle stick instruments (59.1%). Post-exposure prophylaxis procedures are known by 68.2% of dental surgeon and 62.5% of dental health assistant. We did not find positive results for hepatitis B, hepatitis C and human immunodeficiency virus (HIV). CONCLUSIONS: We did not found cases of occupational infectious disease. Dental professionals adopt some preventive actions, but a few professionals, even knowing about the risks they will be exposed during work, do not use some protective equipment.

19.
Oxid Med Cell Longev ; 2020: 5238650, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32256951

RESUMO

Oxidative stress is a metabolic disorder linked with several chronic diseases, and this condition can be improved by natural antioxidants. The fruit pulp of the palm Acrocomia aculeata (Jacq.) Lodd. ex Mart. is widely used in the treatment of various illnesses, but as far as we know, there are no reports regarding the properties of its leaves. Thus, we aimed to evaluate the antioxidant activity of A. aculeata leaf extracts obtained with water (EA-Aa), ethanol (EE-Aa), and methanol (EM-Aa) solvents. The extracts were chemically characterized, and their antioxidant activity was assessed through the scavenging of the free radicals DPPH and ABTS. EE-Aa and EM-Aa showed the highest amounts of phenolic compounds and free radical scavenging activity. However, EA-Aa was more efficient to protect human erythrocytes against AAPH-induced hemolysis and lipid peroxidation. Thus, we further show the antioxidant effect of EA-Aa in preventing AAPH-induced protein oxidation, H2O2-induced DNA fragmentation, and ROS generation in Cos-7 cells. Increased levels of Sirt1, catalase, and activation of ERK and Nrf2 were observed in Cos-7 treated with EA-Aa. We also verify increased survival in nematodes C. elegans, when induced to the oxidative condition by Juglone. Therefore, our results showed a typical chemical composition of plants for all extracts, but the diversity of compounds presented in EA-Aa is involved in the lower toxicity and antioxidant properties provided to the macromolecules tested, proteins, DNA, and lipids. This protective effect also proven in Cos-7 and in C. elegans was probably due to the activation of the Sirt1/Nrf2 pathway. Altogether, the low toxicity and the antioxidant properties of EA-Aa showed in all the experimental models support its further use in the treatment of oxidative stress-related diseases.


Assuntos
Frutas/química , Folhas de Planta/química , Sirtuína 1/química , Humanos , Estresse Oxidativo
20.
Rev Bras Med Trab ; 17(1): 61-68, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32270105

RESUMO

BACKGROUND: Work might cause severe physical stress associated with emotional overload, especially among hospital employees. OBJECTIVE: To identify risk factors for cardiovascular diseases and occupational stress among employees of a teaching hospital. METHOD: Cross-sectional study conducted with 45 employees of a philanthropic health institution in the central area of Rio Grande do Sul, Brazil. Data collection was performed to analyze anthropometric variables, blood pressure, biochemical markers and indicators of health and occupational stress. RESULTS: 60.0% of the participants reported sedentary behavior. Analysis of non-modifiable risk factors showed that 55.6% of the sample had family history (mother and father) of hypertension, 22.2% of myocardial infarction and stroke and 13.3% of diabetes. Body mass index categories overweight and obesity predominated (55.5%); 73.4% of the sample was categorized as with moderate-to-high risk to health based on the waist-to-hip ratio; the body fat percentage was above normal or indicated tendency to obesity for 73.3% of the participants. About 71.1% of the sample exhibited excellent or normal blood pressure. Total cholesterol was high or borderline for 88.9% of the sample. On assessment of occupational risk, 55.5% of the participants were categorized as with intermediate degree of exposure. CONCLUSION: The results point to the relevance of health policies to promote lifestyle changes in and outside the workplace with consequent impact on the physical and mental state of workers.


INTRODUÇÃO: A atividade laboral pode trazer consigo profundo estresse físico associado à sobrecarga emocional sobretudo em trabalhadores no ambiente hospitalar. OBJETIVO: Buscou-se identificar os fatores de risco para doenças cardiovasculares e estresse ocupacional em profissionais de um hospital de ensino. MÉTODO: Trata-se de um estudo transversal, realizado com 45 trabalhadores de uma instituição de saúde filantrópica da região central do Rio Grande do Sul. A coleta de dados seguiu com base na premissa de avaliar variáveis antropométricas, pressão arterial, marcadores bioquímicos, indicadores de saúde e estresse ocupacional. RESULTADOS: Dos participantes, 60,0% autorreferiram-se sedentários. A avaliação dos fatores de risco não modificáveis mostrou que 55,6% dos participantes apresentavam histórico familiar (pai e mãe) com hipertensão, 22,2% com infarto e acidente vascular cerebral e 13,3% com diabetes. Houve predominância dos indivíduos com sobrepeso ou obesidade no quesito índice de massa corporal (55,5%): 73,4% apresentaram relação cintura-quadril de moderado a alto risco para a saúde e 73,3% estavam com percentual de gordura acima do normal e tendência à obesidade. 71,1% dos avaliados apresentaram pressão arterial entre ótima e normal. Os marcadores bioquímicos apontaram 88,9% dos participantes apresentando colesterol total nas faixas limítrofe ou alta. Na avaliação do estresse ocupacional, 55,5% dos trabalhadores encontram-se no grupo de exposição intermediária. CONCLUSÃO: Os resultados encontrados ressaltam a importância de políticas de saúde que incentivem a mudança do estilo de vida dentro e fora do trabalho, com impacto direto nas condições de saúde física e mental dos trabalhadores.

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