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1.
Braz Oral Res ; 38: e016, 2024.
Article in English | MEDLINE | ID: mdl-38477802

ABSTRACT

The pathogenic nature of infections caused by Candida spp. underscores the necessity for novel therapeutic agents. Extracts of Schinopsis brasilienses Engl are \ a promising source of agents with antifungal effects. This study aimed to assess the antifungal potential of the leaf extract of S. brasilienses. The antifungal activity was evaluated by determining the minimum inhibitory concentrations and fungicide concentrations (MIC and MFC). The antibiofilm potential was assessed by counting colony-forming units/mL. The study examined the inhibition kinetics of fungal growth and potential synergism between gallic acid or the extract and nystatin using the Checkerboard method. Cytotoxicity was evaluated through the MTT assay. The extract exhibited antifungal effect against all tested strains, with MIC and MFC ranging from 31.25-250 µg/mL. Gallic acid, the main isolated compound, displayed a MIC of 2000 µg/mL. The extract of S. brasilienses at 31.25 µg/mL inhibited the formation of biofilm by C. albicans and significantly reduced the mass of mature biofilm after 24 and 48 h (p < 0. 05). At a concentration of 125 µg/mL, the extract demonstrated significant inhibition of fungal growth after 6 hours. The combination of gallic acid or extract with nystatin did not exhibit synergistic or antagonistic effect. Furthermore, the extract did not induce cytotoxicity to a human cell line. The extract of S. brasiliensis demonstrates antifungal activity against Candida, generally exhibiting fungicidal action and capacity to inhibit biofilm formation as well as reduce mature biofilms. Additionally, the extract showed low cytotoxicity to human cells.


Subject(s)
Anacardiaceae , Candida , Humans , Antifungal Agents , Nystatin , Candida albicans , Biofilms , Gallic Acid , Plant Extracts
2.
Braz. oral res. (Online) ; 38: e016, 2024. tab, graf
Article in English | LILACS-Express | LILACS, BBO - Dentistry | ID: biblio-1550155

ABSTRACT

Abstract The pathogenic nature of infections caused by Candida spp. underscores the necessity for novel therapeutic agents. Extracts of Schinopsis brasilienses Engl are / a promising source of agents with antifungal effects. This study aimed to assess the antifungal potential of the leaf extract of S. brasilienses. The antifungal activity was evaluated by determining the minimum inhibitory concentrations and fungicide concentrations (MIC and MFC). The antibiofilm potential was assessed by counting colony-forming units/mL. The study examined the inhibition kinetics of fungal growth and potential synergism between gallic acid or the extract and nystatin using the Checkerboard method. Cytotoxicity was evaluated through the MTT assay. The extract exhibited antifungal effect against all tested strains, with MIC and MFC ranging from 31.25-250 μg/mL. Gallic acid, the main isolated compound, displayed a MIC of 2000 μg/mL. The extract of S. brasilienses at 31.25 μg/mL inhibited the formation of biofilm by C. albicans and significantly reduced the mass of mature biofilm after 24 and 48 h (p < 0. 05). At a concentration of 125 μg/mL, the extract demonstrated significant inhibition of fungal growth after 6 hours. The combination of gallic acid or extract with nystatin did not exhibit synergistic or antagonistic effect. Furthermore, the extract did not induce cytotoxicity to a human cell line. The extract of S. brasiliensis demonstrates antifungal activity against Candida, generally exhibiting fungicidal action and capacity to inhibit biofilm formation as well as reduce mature biofilms. Additionally, the extract showed low cytotoxicity to human cells.

3.
Sci Rep ; 13(1): 3330, 2023 02 27.
Article in English | MEDLINE | ID: mdl-36849550

ABSTRACT

The gaining popularity of tobacco and nicotine delivery products, such as electronic cigarettes (e-cigarettes) being perceived as relatively safe is of a medical concern. The long-term safety of these new products remains uncertain for oral health. In this study, in vitro effects of e-liquid were assessed in a panel of normal oral epithelium cell lines (NOE and HMK), oral squamous cell carcinoma (OSCC) human cell lines (CAL27 and HSC3), and a mouse oral cancer cell line (AT84) using cell proliferation, survival/cell death, and cell invasion assays. In addition, signaling pathways underlying the pro-invasive activity of e-cigarettes were evaluated by gene and protein expression analysis. We demonstrated that e-liquid promotes proliferation and anchorage-independent growth of OSCC and induces morphological changes associated with enhanced motility and invasive phenotypes. Furthermore, e-liquid-exposed cells express significantly reduced cell viability, regardless of e-cigarette flavour content. At the gene expression level, e-liquid induces changes in gene expression consistent with epithelial to mesenchymal transition (EMT) revealed by reduced expression of cell epithelial markers such as E-cadherin and enhanced expression of mesenchymal proteins like vimentin and B-catenin seen both in OSCC cell lines and normal oral epithelium cells. In summary, the ability of e-liquid to induce proliferative and invasive properties along the activation of the EMT process can contribute to the development of tumorigenesis in normal epithelial cells and promote aggressive phenotype in pre-existing oral malignant cells.


Subject(s)
Carcinoma, Squamous Cell , Electronic Nicotine Delivery Systems , Head and Neck Neoplasms , Mouth Neoplasms , Humans , Animals , Mice , Carcinoma, Squamous Cell/genetics , Squamous Cell Carcinoma of Head and Neck , Epithelial-Mesenchymal Transition , Mouth Neoplasms/genetics , Epithelial Cells
4.
Cells ; 12(1)2022 12 29.
Article in English | MEDLINE | ID: mdl-36611933

ABSTRACT

Papillary thyroid carcinoma (PTC) is the most common malignancy of the thyroid gland and early stages are curable. However, a subset of PTCs shows an unusually aggressive phenotype with extensive lymph node metastasis and higher incidence of locoregional recurrence. In this study, we investigated a large cohort of PTC cases with an unusual aggressive phenotype using a high-throughput RNA sequencing (RNA-Seq) to identify differentially regulated genes associated with metastatic PTC. All metastatic PTC with mutated BRAF (V600E) but not BRAF wild-type expressed an up-regulation of R-Spondin Protein 4 (RSPO4) concomitant with an upregulation of genes involved in focal adhesion and cell-extracellular matrix signaling. Further immunohistochemistry validation confirmed the upregulation of these target genes in metastatic PTC cases. Preclinical studies using established PTC cell lines support that RSPO4 overexpression is associated with BRAF V600E mutation and is a critical upstream event that promote activation of kinases of focal adhesion signaling known to drive cancer cell locomotion and invasion. This finding opens up the potential of co-targeting B-Raf, RSPO and focal adhesion proteins as a pharmacological approach for aggressive BRAF V600E PTC.


Subject(s)
Carcinoma, Papillary , Thyroid Neoplasms , Humans , Thyroid Cancer, Papillary/genetics , Thyroid Cancer, Papillary/pathology , Thyroid Neoplasms/metabolism , Carcinoma, Papillary/genetics , Carcinoma, Papillary/pathology , Mutation/genetics , Neoplasm Recurrence, Local , Proto-Oncogene Proteins B-raf/genetics
5.
Int J Biochem Cell Biol ; 134: 105964, 2021 05.
Article in English | MEDLINE | ID: mdl-33667680

ABSTRACT

Head and neck squamous cell carcinoma (HNSCC), a prevalent cancer worldwide, has a high incidence of loco-regional dissemination, frequent recurrence, and lower 5-year survival rates. Current gold standard treatments for advanced HNSCC rely primarily on radiotherapy and chemotherapy but with limited efficacy and significant side effects. In this study, we characterized a novel 5-fluorouracil (5-FU) carrier composed of chitosan solution (CS) and polycaprolactone (PCL) microparticles (MPs) in HNSCC preclinical models. The designed MPs were evaluated for their size, morphology, drug entrapment efficiency (EE%) and in vitro drug release profile. The anti-cancer activity of 5-FU-loaded particles was assessed in HNSCC human cell lines (CAL27 and HSC3) and in a preclinical mouse model (AT84) utilizing cell proliferation and survival, cell motility, and autophagy endpoints. The results demonstrated a 38.57 % in 5-FU entrapment efficiency associated with reduced 5-FU in vitro release up to 96 h post-exposure. Furthermore, CS-decorated PCL MPs were able to promote a significant inhibition of cancer cell proliferation based on the metabolic and colony formation assays, in comparison to controls. In contrast, CS-decorated PCL MPs did not influence the pharmacological efficacy of 5-FU to inhibit in vitro cancer cell migration. Last, cell protein analysis revealed a significant increase of autophagy and cell death evaluated by LC3-II expression and PARP1 cleavage, respectively. In summary, these results support the potential utility of CS-decorated PCL MPs as an effective 5-FU-delivery carrier to improve HNSCC therapeutic management.


Subject(s)
Antimetabolites, Antineoplastic/pharmacology , Chitosan/chemistry , Head and Neck Neoplasms/drug therapy , Nanoparticles/administration & dosage , Polyesters/chemistry , Animals , Antimetabolites, Antineoplastic/administration & dosage , Antimetabolites, Antineoplastic/chemistry , Autophagy/drug effects , Cell Line, Tumor , Cell Survival/drug effects , Chitosan/administration & dosage , Drug Liberation , Fluorouracil/administration & dosage , Fluorouracil/chemistry , Head and Neck Neoplasms/metabolism , Head and Neck Neoplasms/pathology , Humans , Mice , Nanoparticles/chemistry , Particle Size , Polyesters/administration & dosage
6.
Front Bioeng Biotechnol ; 8: 571821, 2020.
Article in English | MEDLINE | ID: mdl-33195132

ABSTRACT

The aim of this study was to develop polymeric nanofibers for controlled administration of Amphotericin B (AmpB), using the solution centrifugation technique, characterizing its microstructural and physical properties, release rate, and activity against Leishmania and Candida species. The core-shell nanofibers incorporated with AmpB were synthesized by Solution Blow Spinning (SBS) and characterized by scanning electron microscopy (SEM), differential scanning calorimetry, X-Ray diffraction, and drug release assay. In vitro leishmanicidal and antifungal activity were also evaluated. Fibrous membranes with uniform morphology and smooth surfaces were produced. The intensity of the diffraction peaks becomes slightly more pronounced, assuming the increased crystallization in PLA/PEG at high AmpB loadings. Drug release occurred and the solutions with nanofibers to encourage greater incorporation of AmpB showed a higher concentration. In the results of the experiment with promastigotes, the wells treated with nanofibers containing concentrations of AmpB at 0.25, 0.5, and 1%, did not have any viable cells, similar to the positive control. Various concentrations of AmpB improved the inhibition of fungal growth. The delivery system based on PLA/PEG nanofibers was properly developed for AmpB, presenting a controlled release and a successful encapsulation, as well as antifungal and antileishmanial activity.

8.
Nanomaterials (Basel) ; 10(10)2020 Sep 29.
Article in English | MEDLINE | ID: mdl-33003387

ABSTRACT

Head and neck cancer (HNC) is a complex and heterogeneous disease associated with high mortality and morbidity worldwide. Standard therapeutic management of advanced HNC, which is based on radiotherapy often combined with chemotherapy, has been hampered by severe long-term side effects. To overcome these side effects, tumor-selective nanoparticles have been exploited as a potential drug delivery system to improve HNC therapy. A combination of MEDLINE, EMBASE, Cochrane Oral Health Group's Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL) and ClinicalTrials.gov from inception up to June 2020 was used for this systematic review. A total of 1747 published manuscripts were reviewed and nine relevant references were retrieved for analysis, while eight of them were eligible for meta-analysis. Based on these studies, the level of evidence about the efficacy of nanoformulation for HNC therapy on tumor response and adverse side effects (SAE) was low. Even though basic research studies have revealed a greater promise of nanomaterial to improve the outcome of cancer therapy, none of them were translated into clinical benefits for HNC patients. This systematic review summarized and discussed the recent progress in the development of targeted nanoparticle approaches for HNC management, and open-up new avenues for future perspectives.

9.
Carcinogenesis ; 41(6): 769-777, 2020 07 10.
Article in English | MEDLINE | ID: mdl-32112078

ABSTRACT

Regional metastasis is the single most important prognostic factor in oral squamous cell carcinoma (OSCC). Abnormal expression of N-myc downstream-regulated genes (NDRGs) has been identified to occur in several tumor types and to predict poor prognosis. In OSCC, the clinical significance of deregulated NDRG expression has not been fully established. In this study, NDRG1 relevance was assessed at gene and protein levels in 100 OSCC patients followed up by at least 10 years. Survival outcome was analyzed using a multivariable analysis. Tumor progression and metastasis was investigated in preclinical model using oral cancer cell lines (HSC3 and SCC25) treated with epidermal growth factor (EGF) and orthotopic mouse model of metastatic murine OSCC (AT84). We identified NDRG1 expression levels to be significantly lower in patients with metastatic tumors compared with patients with local disease only (P = 0.001). NDRG1 expression was associated with MMP-2, -9, -10 (P = 0.022, P = 0.002, P = 0.042, respectively) and BCL2 (P = 0.035). NDRG1 lower expression was able to predict recurrence and metastasis (log-rank test, P = 0.001). In multivariable analysis, the expression of NDRG1 was an independent prognostic factor (Cox regression, P = 0.013). In invasive OSCC cells, NDRG1 expression is diminished in response to EGF and this was associated with a potent induction of epithelial-mesenchymal transition phenotype. This result was further confirmed in an orthotopic OSCC mouse model. Together, this data support that NDRG1 downregulation is a potential predictor of metastasis and approaches aimed at NDRG1 signaling rescue can serve as potential therapeutic strategy to prevent oral cancer progression to metastasis.


Subject(s)
Biomarkers, Tumor/metabolism , Carcinoma, Squamous Cell/secondary , Cell Cycle Proteins/metabolism , Epithelial-Mesenchymal Transition , Gene Expression Regulation, Neoplastic , Intracellular Signaling Peptides and Proteins/metabolism , Mouth Neoplasms/pathology , Neoplasm Recurrence, Local/pathology , Animals , Apoptosis , Biomarkers, Tumor/genetics , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/metabolism , Cell Cycle Proteins/genetics , Cell Proliferation , Female , Humans , Intracellular Signaling Peptides and Proteins/genetics , Mice , Mice, Inbred BALB C , Mice, Nude , Mouth Neoplasms/genetics , Mouth Neoplasms/metabolism , Neoplasm Recurrence, Local/genetics , Neoplasm Recurrence, Local/metabolism , Prognosis , Survival Rate , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
10.
Biomed Res Int ; 2019: 3210530, 2019.
Article in English | MEDLINE | ID: mdl-31309105

ABSTRACT

Bioactive glasses (BG) applications include tissue engineering for bone regeneration, coating for implants, and scaffolds for wound healing. BG can be conjugated to ions like silver, which might add some antimicrobial properties to this biomaterial. The immunomodulatory activity of ion-doped bioactive glasses particles was not investigated before. The aim of this work was to evaluate the cytotoxic and immunomodulatory effect of BG and silver-doped bioactive glass (BGAg) in human peripheral blood cells. BG and BGAg samples belonging to the system 58SiO2 •(36-x)CaO·6P2O5 ·xAg2O, where x = 0 and 1 mol%, respectively, were synthesized via sol-gel method and characterized. Cytotoxicity, modulation of cytokine production (TNF-α, IL-1ß, IL-6, IL-4, and IL-10), and oxidative stress response were investigated in human polymorphonuclear cells (PMNs) and peripheral blood mononuclear cells (PBMCs) cultures. Cell viability in the presence of BG or BGAg was concentration-dependent. In addition, BGAg presented higher PBMCs toxicity (LC50 = 0.005%) when compared to BG (LC50 = 0.106%). Interestingly, interleukin4 was produced by PBMCs in response to BG and BGAg in absence of phytohemagglutinin (PHA) and did not modulate PHA-induced cytokine levels. Subtoxic concentrations (0.031% for BG and 0.0008% for BGAg) did not change other cytokines in PBMCs nor reactive oxygen species (ROS) production by PMN. However, BG and BGAg particles decreased zymosan-induced ROS levels in PMN. Although ion incorporation increased BG cytotoxicity, the bioactive glass particles demonstrated a in vitro anti-inflammatory potencial. Future studies are needed to clarify the scavenger potential of the BG/BGAg particles/scaffolds as well as elucidate the effect of the anti-inflammatory potential in modulating tissue growth in vivo.


Subject(s)
Biocompatible Materials/administration & dosage , Cytokines/metabolism , Glass/chemistry , Leukocytes, Mononuclear/metabolism , Silver/administration & dosage , Cell Line , Cell Survival/drug effects , Humans , Inflammation/metabolism , Reactive Oxygen Species/metabolism , Tissue Engineering/methods , Wound Healing/drug effects
11.
Article in English | BBO - Dentistry , LILACS | ID: biblio-1056863

ABSTRACT

Abstract Objective: To perform chemical analysis and to evaluate the anti-biofilm and hemolytic effect of the essential oil of Cymbopogon citratus. Material and Methods: Gaseous chromatography coupled to mass spectrometer was performed for chemical characterization of the essential oil. To verify the antimicrobial action, the Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC) and Minimum Fungicidal Concentration (MFC) were determined. From MIC, MBC and MFC data, concentrations were established to verify the anti-biofilm effect and for the hemolysis test on human erythrocytes. A multispecies biofilm was developed in vitro and mouthwash applications were simulated to determine the inhibition of biofilm formation or its removal. Results were analyzed through ANOVA statistical test, complemented by the Tukey test, considering a significance level of 5% Results: The major component of the essential oil is citral. MIC verified for Streptococcus mutans was 1mg / mL, while for Candida albicans, it was 125 μg/mL, presenting microbicidal effect for both microorganisms tested. The essential oil was able to inhibit biofilm formation (p<0.001), presenting non-toxic hemolysis percentage in concentration below 500 μg/mL Conclusion: The essential oil of Cymbopogon citratus is antimicrobial, antibiofilm and non-toxic to human erythrocytes, representing a natural product with potential for use in Dentistry.


Subject(s)
Plants, Medicinal , Oils, Volatile , Biofilms , Cymbopogon , Anti-Bacterial Agents/immunology , Streptococcus mutans , In Vitro Techniques , Brazil , Microbial Sensitivity Tests , Analysis of Variance , Chromatography , Statistics, Nonparametric
12.
Article in English | MEDLINE | ID: mdl-30416530

ABSTRACT

The present study demonstrates the antifungal potential of chemically characterized essential oil (EO) of Cinnamomum zeylanicum Blume on Candida spp. biofilm and establishes its mode of action, effect on fungal growth kinetics, and cytotoxicity to human cells. The minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) values varied from 62.5 to 1,000 µg/mL, and the effect seems to be due to interference with cell wall biosynthesis. The kinetics assay showed that EO at MICx2 (500 µg/mL) induced a significant (p < 0.05) reduction of the fungal growth after exposure for 8 h. At this concentration, the EO was also able to hinder biofilm formation and reduce Candida spp. monospecies and multispecies in mature biofilm at 24 h and 48 h (p < 0.05). A protective effect on human red blood cells was detected with the EO at concentrations up to 750 µg/mL, as well as an absence of a significant reduction (p > 0.05) in the viability of human red blood cells at concentrations up to 1,000 µg/mL. Phytochemical analysis identified eugenol as the main component (68.96%) of the EO. C. zeylanicum Blume EO shows antifungal activity, action on the yeast cell wall, and a deleterious effect on Candida spp. biofilms. This natural product did not show evidence of cytotoxicity toward human cells.

13.
Molecules ; 22(9)2017 Sep 17.
Article in English | MEDLINE | ID: mdl-28926981

ABSTRACT

We evaluated the antifungal and anti-biofilm activity, mechanism of action and cytotoxicity of chloramine T trihydrate (CAT) against Candida spp. The Minimum Inhibitory and Fungicidal Concentrations (MIC/MFC) of CAT were determined. Changes in CAT-treated C. albicans growth kinetics and micromorphology were evaluated, as well as the mechanism of action, and its effects on biofilm. Cytotoxicity was assessed by the hemolysis method. The data were analyzed by inferential statistics (p ≤ 0.05). CAT showed antifungal activity against all strains, with MIC values ranging between 1.38 and 5.54 mmol/L (MIC75%: 2.77 mmol/L). CAT demonstrated an immediate and sustained action on C. albicans growth kinetics, particularly at 2 × MIC. This compound likely acts on the cell wall and membrane permeability simultaneously and was found to cause changes in C. albicans micromorphology. Tha antibiofilm activity of CAT was similar to that of sodium hypochlorite (p > 0.05) against mature biofilms. CAT was more effective than NaOCl in reducing mature biofilm upon 1-min exposure at 2 × MIC (24 h) and 4 × MIC (48 h) (p < 0.05). Toxicological analysis revealed that CAT had hemolytic activity between 61 and 67.7% as compared to 100% by NaOCl. CAT has antifungal and anti-biofilm properties, probably acting on both cell wall and membrane permeability, and showed low toxicity in vitro.


Subject(s)
Antifungal Agents/pharmacology , Biofilms/drug effects , Candida albicans/drug effects , Chloramines/pharmacology , Disinfectants/pharmacology , Tosyl Compounds/pharmacology , Antifungal Agents/toxicity , Candida albicans/growth & development , Cell Line , Cell Survival/drug effects , Chloramines/toxicity , Disinfectants/toxicity , Hemolysis , Humans , Kinetics , Permeability , Tosyl Compounds/toxicity
14.
Rev. odontol. Univ. Cid. São Paulo (Online) ; 28(2): 101-109, maio-ago.-out. 2016. Tabelas
Article in Portuguese | LILACS, BBO - Dentistry | ID: biblio-832173

ABSTRACT

O presente estudo teve como objetivos avaliar a prevalência de caninos superiores não irrompidos, suas posições intraósseas e se há relação com a idade e o gênero. Foram avaliadas 100 radiografias panorâmicas digitais, no período compreendido entre os anos de 2009 a 2010. Para a coleta de dados foi utilizada uma ficha específica onde se registrou a idade, gênero e posicionamento dos elementos. Para análise da angulação e distância da cúspide do canino à crista do rebordo alveolar foi utilizado o programa Meazure®. Os resultados apontaram para uma prevalência de 61,1% para o gênero feminino, faixa etária entre 21 a 25 anos (44, 4%), unilateralidade (83, 3%) e posição mesioangular (77, 7%). Com respeito aos valores médios para as medidas de angulação dos caninos em relação a linha média e da distância da cúspide à crista do rebordo alveolar os resultados revelaram que as mulheres apresentam tanto angulação média (44,20) quanto distância média (9,30) superiores às medidas dos homens. Por fim, avaliando tais medições em relação à posição do canino, percebe-se que os dentes mesioangulares unilaterais têm angulação média menor (36,80) e distância média maior (10,56) que as dos dentes identificados nas posições vertical e horizontal. A média geral da angulação dos pacientes que apresentaram caninos não irrompidos unilaterais foi de 42,67° e com distância de 9,02mm. Desta forma, conclui-se que caninos não irrompidos são prevalentes em indivíduos jovens do gênero feminino, apresentando-se predominância unilateral e em posição mesioangular


The present study aimed to evaluate the prevalence of unerupted maxillary canines, the intraosseous position and the prevalence of unerupted canines related to age and gender. 100 digital panoramic radiographs were evaluated at the period between the years 2009-2010. A specific record were developed for collection data related to age, gender and placement of the elements. For analysis of the angle and canine distance of the cusp to the crest of the alveolar ridge Meazure® was used. The results showed a prevalence of females (61,1%), aged between 21-25 years (44,4%), unilateral (83,3%) and mesioangular position (77,7%). In respect to the average for measures of canine angulation in relation to the midline and the distance of the leaflet to the crest of the alveolar ridge values, the results revealed that women present both mean angulation (44.20) and average distance (9.30) superior to measures of men. Evaluating such measurements relative to the position of the canine, can be noted that the mesioangular teeth have unilateral lower mean angle (36.80) and greater average distance (10.56) that the teeth in vertical and horizontal position. The mean angulation of patients with unilateral unerupted canines was 42.67° and distance of 9.02 mm. Thus, it is concluded that unerupted canines are prevalent in young females, presenting predominantly unilateral and mesioangular position


Subject(s)
Cuspid , Tooth, Unerupted , Radiography, Panoramic
15.
Biomed Res Int ; 2015: 247965, 2015.
Article in English | MEDLINE | ID: mdl-25759815

ABSTRACT

Chitosan is a polysaccharide composed of randomly distributed chains of ß-(1-4) D-glucosamine and N-acetyl-D-glucosamine. This compound is obtained by partial or total deacetylation of chitin in acidic solution. The chitosan-based hemostatic agents have been gaining much attention in the management of bleeding. The aim of this study was to evaluate in vitro hemagglutination activity of chitosan nanoparticles using human erythrocytes. The preparation of nanoparticles was achieved by ionotropic gelification technique followed by neutralization with NaOH 1 mol/L(-1). The hemagglutination activity was performed on a solution of 2% erythrocytes (pH 7.4 on PBS) collected from five healthy volunteers. The hemolysis determination was made by spectrophotometric analysis. Chitosan nanoparticle solutions without NaOH addition changed the reddish colour of the wells into brown, suggesting an oxidative reaction of hemoglobin and possible cell lysis. All neutralized solutions of chitosan nanoparticles presented positive haemagglutination, without any change in reaction color. Chitosan nanoparticles presented hemolytic activity ranging from 186.20 to 223.12%, while neutralized solutions ranged from 2.56 to 72.54%, comparing to distilled water. Results highlight the need for development of new routes of synthesis of chitosan nanoparticles within human physiologic pH.


Subject(s)
Chitosan/administration & dosage , Erythrocytes/drug effects , Hemagglutination/drug effects , Nanoparticles/administration & dosage , Acetylglucosamine/administration & dosage , Biocompatible Materials/administration & dosage , Chitin/metabolism , Erythrocytes/metabolism , Hemolysis/drug effects , Humans , Hydrogen-Ion Concentration , Particle Size , Solutions/administration & dosage
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