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1.
Int J Biol Macromol ; 270(Pt 1): 132379, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38754680

RESUMO

Hydrogels based on natural polysaccharides have demonstrated efficacy in epithelial recovery from cutaneous burn wounds. Here, we prepared a double-network hydrogel consisting of galactomannan (from Cassia grandis seeds) and κ-carrageenan (commercially sourced), cross-linked with CaCl2, as a matrix for immobilizing lactoferrin and/or Cramoll, aiming at its applicability as dressings for second-degree burn wounds. The formulations obtained [H - hydrogel, HL - hydrogel + lactoferrin, HC - hydrogel + Cramoll and HLC - hydrogel + lactoferrin + Cramoll] were analyzed rheologically as well as in terms of their stability (pH, color, microbial contamination) for 90 days. The burn was created with an aluminum bar (97 ± 3 °C) in the dorsal region of Wistar rats and subsequently treated with hydrogels (H, HL, HC, HLC) and control saline solution (S). The burn was monitored for 3, 7 and 14 days to evaluate the efficacy of the hydrogels in promoting wound healing. The hydrogels did not reveal significant pH or microbiological changes; there was an increase in brightness and a reduction in opacity for H. The rheological analysis confirmed the gel-like viscoelastic signature of the systems without substantial modification of the basic rheological characteristics, however HLC proved to be more rigid, due to rheological synergy when combining protein biomolecules. Macroscopic analyses confirmed centripetal healing with wound contraction: S < H < HC < HL < HLC. Histopathological analyses showed that hydrogel-treated groups reduced inflammation, tissue necrosis and fibrosis, while promoting re-epithelialization with focal acanthosis, especially in HLC due to a positive synergistic effect, indicating its potential as a promising therapy in the repair of burns.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33029179

RESUMO

Babassu (Attalea speciosa Mart. ex Spreng., Arecaceae) is a palm tree endemic to Brazil and found mainly in the borders of Amazon forest, where the harvesting of its fruits is an important source of income for more than 300,000 people. Among the communities of coconut breakers women, babassu oil is used in culinary, as fuel, and mostly as medicinal oil for the treatment of skin wounds and inflammation. This study aimed to evaluate in vitro and in vivo the wound healing effects of babassu oil. In vitro, babassu oil increased the migration of L929 fibroblasts, inhibited the production of nitric oxide by LPS-stimulated peritoneal macrophages, and increased the levels of INF-γ and IL-6 cytokines production. In vivo, babassu oil accelerated the healing process in a full-thickness splinted wound model, by an increase in the fibroblasts number, blood vessels, and collagen deposition in the wounds. The babassu oil also increased the recruitment of inflammatory cells into the wound site and showed an anti-inflammatory effect in a chronic ear edema model, reducing ear thickness, epidermal hyperplasia, and myeloperoxidase activity. Thus, these data corroborate the use of babassu oil in folk medicine as a remedy to treat skin wounds.

3.
Toxicon ; 185: 114-119, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32659238

RESUMO

Scorpion envenomation represents an important health problem in many parts of the world, due to the high number and severity of accidents. Recent studies demonstrated that some species can produce venoms with genetic damage potential. Here, we evaluated whether Tityus stigmurus venom causes genetic damage in blood and testicular cells of Swiss mice. We also analyzed the effect of the venom on the number of spermatogenic lineage cells. Five groups of mice received 0.387 mg/kg of the venom, intraperitoneally; one group received saline solution (control group). Blood and testicular cells were collected for comet assay and histological analysis at different times after treatment (1, 2, 6, 12, and 48 h). Blood was also collected 48 h after treatment for the micronucleus test in erythrocytes. Histological analysis was performed by counting cells of the spermatogenic lineages; the nuclear area of elongated spermatocytes was also evaluated. Treatment with the venom induced DNA damage that endured from 1 h to 48 h, as confirmed by the comet assay. The micronucleus test demonstrated that the venom induced mutations in erythrocytes. The number of spermatogonia and rounded spermatids decreased in some groups; the number of elongated spermatids increased, and their nuclear size decreased 1 h after treatment. Genetic damage can be caused directly by the venom, but we suggested that reactive oxygen species that result from inflammatory process caused by the envenomation may have an important role in the DNA damage. Genetic damage and apoptosis may explain the changes in the number of spermatogenic cells. Furthermore, the decrease in nuclear area may result from chromatin loss. Genetic damage in testicular cells, associated with alterations in the number and morphology of spermatogenic cells, can result in reproduction disorders in animals, or humans, stung by T. stigmurus.


Assuntos
Venenos de Escorpião/toxicidade , Escorpiões , Animais , Ensaio Cometa , Dano ao DNA , Humanos , Masculino , Camundongos , Testículo
4.
An Acad Bras Cienc ; 88 Suppl 1: 665-75, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27142547

RESUMO

Scorpions belonging to the Tityus genus are of medical interest in Brazil. Among them, Tityus stigmurus is the main scorpion responsible for stings in the Northeast region. After a sting, the scorpion venom distributes rapidly to the organs, reaching the kidneys quickly. However, there are few studies concerning the renal pathophysiology of scorpion poisoning. In this study, we evaluated the effects of T. stigmurus venom (TsV) on renal parameters in isolated rat kidneys. Wistar rats (n = 6), weighing 250-300 g, were perfused with Krebs-Henseleit solution containing 6 g/100 mL bovine serum albumin. TsV at 0.3 and 1.0 µg/mL was tested, and the effects on perfusion pressure (PP), renal vascular resistance (RVR), urinary flow (UF), glomerular filtration rate (GFR), and electrolyte excretion were analyzed. Effects were observed only at TsV concentration of 1.0 µg/mL, which increased PP (controlPP40' = 92.7 ± 1.95; TsVPP40' = 182.0 ± 4.70* mmHg, *p < 0.05), RVR (controlRVR40' = 3.28 ± 0.23 mmHg; TstRVR40' = 6.76 ± 0.45* mmHg, *p < 0.05), UF (controlUF50' = 0.16 ± 0.04; TstUF50' = 0.60 ± 0.10* mL/g/min,*p < 0.05), GFR and electrolyte excretion, with histological changes that indicate renal tubular injury. In conclusion, T. stigmurus venom induces a transient increase in PP with tubular injury, both of which lead to an augmented electrolyte excretion.


Assuntos
Rim/efeitos dos fármacos , Venenos de Escorpião/farmacologia , Escorpiões , Animais , Brasil , Taxa de Filtração Glomerular/efeitos dos fármacos , Ratos , Ratos Wistar , Escorpiões/classificação
5.
Toxicon ; 74: 19-26, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23911732

RESUMO

Mammalian natriuretic peptides (NPs) have been extensively investigated for use as therapeutic agents in the treatment of cardiovascular diseases. Here, we describe the isolation, sequencing and tridimensional homology modeling of the first C-type natriuretic peptide isolated from scorpion venom. In addition, its effects on the renal function of rats and on the mRNA expression of natriuretic peptide receptors in the kidneys are delineated. Fractionation of Tityus serrulatus venom using chromatographic techniques yielded a peptide with a molecular mass of 2190.64 Da, which exhibited the pattern of disulfide bridges that is characteristic of a C-type NP (TsNP, T. serrulatus Natriuretic Peptide). In the isolated perfused rat kidney assay, treatment with two concentrations of TsNP (0.03 and 0.1 µg/mL) increased the perfusion pressure, glomerular filtration rate and urinary flow. After 60 min of treatment at both concentrations, the percentages of sodium, potassium and chloride transport were decreased, and the urinary cGMP concentration was elevated. Natriuretic peptide receptor-A (NPR-A) mRNA expression was down regulated in the kidneys treated with both concentrations of TsNP, whereas NPR-B, NPR-C and CG-C mRNAs were up regulated at the 0.1 µg/mL concentration. In conclusion, this work describes the isolation and modeling of the first natriuretic peptide isolated from scorpion venom. In addition, examinations of the renal actions of TsNP indicate that its effects may be related to the activation of NPR-B, NPR-C and GC-C.


Assuntos
Rim/efeitos dos fármacos , Peptídeo Natriurético Tipo C/isolamento & purificação , Venenos de Escorpião/isolamento & purificação , Escorpiões/química , Sequência de Aminoácidos , Animais , Brasil , GMP Cíclico/genética , GMP Cíclico/metabolismo , Regulação para Baixo , Taxa de Filtração Glomerular , Rim/metabolismo , Masculino , Dados de Sequência Molecular , Peptídeo Natriurético Tipo C/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Receptores do Fator Natriurético Atrial/genética , Receptores do Fator Natriurético Atrial/metabolismo , Venenos de Escorpião/química , Alinhamento de Sequência , Regulação para Cima
6.
Toxicon ; 54(4): 413-20, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19463845

RESUMO

Sea anemones contain a variety of biologically active substances. Bunodosoma caissarum is a sea anemone from the Cnidaria phylum, found only in Brazilian coastal waters. The aim of the present work was to study the biological effects of PLA(2) isolated from the sea anemone B. caissarum on the isolated perfused kidney, the arteriolar mesenteric bed and on insulin secretion. Specimens of B. caissarum were collected from the São Vicente Channel on the southern coast of the State of São Paulo, Brazil. Reverse phase HPLC analysis of the crude extract of B. caissarum detected three PLA(2) proteins (named BcPLA(2)1, BcPLA(2)2 and BcPLA(2)3) found to be active in B. caissarum extracts. MALDI-TOF mass spectrometry of BcPLA(2)1 showed one main peak at 14.7 kDa. The N-terminal amino acid sequence of BcPLA(2)1 showed high amino acid sequence identity with PLA(2) group III protein isolated from the Mexican lizard (PA23 HELSU, HELSU, PA22 HELSU) and with the honey bee Apis mellifera (PLA(2) and 1POC_A). In addition, BcPLA(2)1 also showed significant overall homology to bee PLA(2). The enzymatic activity induced by native BcPLA(2)1 (20 microg/well) was reduced by chemical treatment with p-bromophenacyl bromide (p-BPB) and with morin. BcPLA(2)1 strongly induced insulin secretion in presence of high glucose concentration. In isolated kidney, the PLA(2) from B. caissarum increased the perfusion pressure, renal vascular resistance, urinary flow, glomerular filtration rate, and sodium, potassium and chloride levels of excretion. BcPLA(2)1, however, did not increase the perfusion pressure on the mesenteric vascular bed. In conclusion, PLA(2), a group III phospholipase isolated from the sea anemone B. caissarum, exerted effects on renal function and induced insulin secretion in conditions of high glucose concentration.


Assuntos
Fosfolipases A2/farmacologia , Anêmonas-do-Mar/enzimologia , Sequência de Aminoácidos , Animais , Cromatografia Líquida de Alta Pressão , Glucose/metabolismo , Técnicas In Vitro , Insulina/metabolismo , Secreção de Insulina , Rim/efeitos dos fármacos , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Dados de Sequência Molecular , Fosfolipases A2/química , Fosfolipases A2/isolamento & purificação , Ratos , Ratos Wistar , Alinhamento de Sequência , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
7.
Acta Med Port ; 21(6): 567-74, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19331790

RESUMO

Multiple risk factors for cardiovascular disorders, particularly hypercholesterolemia, are often present in hypertensive patients. Several studies have shown that antihypertensive drugs affect the lipid profile, increasing the risk of cardiovascular diseases. Here, it was investigated the lipoprotein metabolism alterations in a group of hypertensive patients in care by the Hypertension and Diabetes Program of a public hospital in Fortaleza-CE/Brazil. In this study, one hundred sixty nine serum samples from hypertensive patients (32-87 years old) under antihypertensive therapy were analyzed. Triglycerides, total cholesterol, cholesterol from high density lipoprotein (HDL) and from low density lipoprotein (LDL) serum levels were determined by enzymatic colorimetric method and AI and B apolipoproteins by immunoturbidimetric assay. The population enrolled was predominantly women (73.13%) and from these, 33.53% taking the monotherapy regimen, used angiotensin converting enzyme inhibitors (ACE-I). However, in combined therapy (66.47%) the most used drugs were the diuretics, especially in prescriptions associated to ACE-I. It was also observed that patients taking diuretics in monotherapy regimen showed significant effects in their serum lipid concentrations of lipids, in contrast with individuals taking combined therapy, which had no expressive alterations in their lipid profile. Theses results suggest that the antihypertensive therapy must be associated to a lipid monitoring process.


Assuntos
Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Hipertensão/metabolismo , Lipoproteínas/efeitos dos fármacos , Lipoproteínas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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