Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Cell Mol Biol (Noisy-le-grand) ; 69(3): 113-117, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37300681

RESUMO

CD36, a fatty acid translocator and NRF2, a transcription factor, are two important players in inflammation and oxidative stress, including in the central nervous system. Both were associated with neurodegeneration as tilting arms of a balance: while activation of CD36 participates in neuroinflammation, activation of NRF2 seems to protect against oxidative stress and neuroinflammation. This study aimed to establish whether tilting the balance one way or the other, by knocking out either of them (NRF2-/- or CD36-/-), would show that one holds higher weight over the other in the cognitive behaviour of mice. We tested both young and old knockout animals in a long-term testing protocol (over one month), using the 8-arm radial maze,. Young NRF2-/- mice exhibited a sustained anxious-like behaviour, which was not recapitulated in old mice nor CD36 -/- mice of either age. Neither knockout strain exhibited cognitive alterations, although CD36 -/- mice showed some improvement over WT littermates. In conclusion, NRF2-/- seems to affect behaviour of mice early in life, and could be considered a vulnerability factor for neurocognition, while CD36 impact on cognitive protection of the aging brain requires more investigation.


Assuntos
Fator 2 Relacionado a NF-E2 , Doenças Neuroinflamatórias , Camundongos , Animais , Camundongos Knockout , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/genética , Inflamação/genética , Camundongos Endogâmicos C57BL
2.
Int J Mol Sci ; 23(5)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35269652

RESUMO

Glioma is the most common primary intracranial tumor and has the greatest prevalence of all brain tumors. Treatment resistance and tumor recurrence in GBM are mostly explained by considerable alterations within the tumor microenvironment, as well as extraordinary cellular and molecular heterogeneity. Soluble factors, extracellular matrix components, tissue-resident cell types, resident or newly recruited immune cells together make up the GBM microenvironment. Regardless of many immune cells, a profound state of tumor immunosuppression is supported and developed, posing a considerable hurdle to cancer cells' immune-mediated destruction. Several studies have suggested that various GBM subtypes present different modifications in their microenvironment, although the importance of the microenvironment in treatment response has yet to be determined. Understanding the microenvironment and how it changes after therapies is critical because it can influence the remaining invasive GSCs and lead to recurrence. This review article sheds light on the various components of the GBM microenvironment and their roles in tumoral development, as well as immune-related biological processes that support the interconnection/interrelationship between different cell types. Also, we summarize the current understanding of the modulation of soluble factors and highlight the dysregulated inflammatory chemokine/specific receptors cascades/networks and their significance in tumorigenesis, cancer-related inflammation, and metastasis.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/metabolismo , Quimiocinas/metabolismo , Glioblastoma/metabolismo , Humanos , Macrófagos/metabolismo , Microglia/metabolismo , Receptores de Quimiocinas/metabolismo , Microambiente Tumoral
3.
Int J Mol Sci ; 23(2)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35054787

RESUMO

Glioblastoma (GBM) is one of the most aggressive tumors of the central nervous system, characterized by a wide range of inter- and intratumor heterogeneity. Accumulation of fatty acids (FA) metabolites was associated with a low survival rate in high-grade glioma patients. The diversity of brain lipids, especially polyunsaturated fatty acids (PUFAs), is greater than in all other organs and several classes of proteins, such as FA transport proteins (FATPs), and FA translocases are considered principal candidates for PUFAs transport through BBB and delivery of PUFAs to brain cells. Among these, the CD36 FA translocase promotes long-chain FA uptake as well as oxidated lipoproteins. Moreover, CD36 binds and recognizes thrombospondin-1 (TSP-1), an extracellular matrix protein that was shown to play a multifaceted role in cancer as part of the tumor microenvironment. Effects on tumor cells are mediated by TSP-1 through the interaction with CD36 as well as CD47, a member of the immunoglobulin superfamily. TSP-1/CD47 interactions have an important role in the modulation of glioma cell invasion and angiogenesis in GBM. Separately, FA, the two membrane receptors CD36, CD47, and their joint ligand TSP-1 all play a part in GBM pathogenesis. The last research has put in light their interconnection/interrelationship in order to exert a cumulative effect in the modulation of the GBM molecular network.


Assuntos
Antígenos CD36/metabolismo , Antígeno CD47/metabolismo , Ácidos Graxos/metabolismo , Glioblastoma/metabolismo , Trombospondina 1/metabolismo , Animais , Progressão da Doença , Glioblastoma/patologia , Humanos , Trombospondina 1/química
4.
J Cell Mol Med ; 22(10): 4597-4610, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30117678

RESUMO

Glioma biology is a major focus in tumour research, primarily due to the aggressiveness and high mortality rate of its most aggressive form, glioblastoma. Progress in understanding the molecular mechanisms behind poor prognosis of glioblastoma, regardless of treatment approaches, has changed the classification of brain tumours after nearly 100 years of relying on anatomopathological criteria. Expanding knowledge in genetic, epigenetic and translational medicine is also beginning to contribute to further elucidating molecular dysregulation in glioma. Long non-coding RNAs (lncRNAs) and their main representatives, large intergenic non-coding RNAs (lincRNAs), have recently been under scrutiny in glioma research, revealing novel mechanisms of pathogenesis and reinforcing others. Among those confirmed was the reactivation of events significant for foetal brain development and neuronal commitment. Novel mechanisms of tumour suppression and activation of stem-like behaviour in tumour cells have also been examined. Interestingly, these processes involve lncRNAs that are present both during normal brain development and in brain malignancies and their reactivation might be explained by epigenetic mechanisms, which we discuss in detail in the present review. In addition, the review discusses the lncRNAs-induced changes, as well as epigenetic changes that are consequential for tumour formation, affecting, in turn, the expression of various types of lncRNAs.


Assuntos
Neoplasias Encefálicas/genética , Encéfalo/metabolismo , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Glioma/genética , RNA Longo não Codificante/genética , RNA Neoplásico/genética , Encéfalo/citologia , Encéfalo/crescimento & desenvolvimento , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Regulação da Expressão Gênica no Desenvolvimento , Glioma/metabolismo , Glioma/patologia , Glioma/terapia , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Terapia de Alvo Molecular , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neurogênese/genética , Neurônios/citologia , Neurônios/metabolismo , Prognóstico , RNA Longo não Codificante/classificação , RNA Longo não Codificante/metabolismo , RNA Neoplásico/metabolismo , Transdução de Sinais
5.
Mediators Inflamm ; 2018: 4285268, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30245588

RESUMO

Keratoconus is a progressive corneal ectasia that may lead to severe visual impairment due to the irregular astigmatism caused by corneal thinning. In addition to its association with atopy, eye rubbing, or genetic component, late reports suggest the involvement of inflammation in the pathogenesis of the disease. Our aim was to determine the concentration of IL-4, IL-6, IL-10, RANTES, IFN gamma, and TNF alpha in the tear film of patients with keratoconus and their first degree family members. We analyzed forty-eight participants in an observational cross-sectional study. The diagnosis of keratoconus had to be confirmed in addition to a minimum of 47 D corneal refractive power by corneal topography readings provided by a Placido-based topography system and analysis of the pattern: irregular astigmatism with an asymmetric "bow-tie." As for the other groups, the most important diagnosis criteria were a normal topographic pattern with a regular astigmatism. 17 keratoconus patients, 16 relatives, and 15 controls were recruited after clinical assessment as part of the research. The cytokine's mean values were similar in the keratoconus group and the relatives' samples but significantly higher compared to the controls. Important differences were found in IL-4 levels between keratoconus patients and relatives and between relatives and controls (mean difference of 302.42, p < 0.0016 and 219.16, p < 0.033, Tukey's HSD procedure). In the keratoconus group, using the CORR procedure, we found statistically strong correlations of IL-6 lacrimal concentrations with the disease stage (r = 0.56, p < 0.01), keratometry (r = 0.55, p < 0.02), pachymetry (r = -0.64, p < 0.048), and corneal hysteresis (r = -0.53, p < 0.02). Cytokine overexpression may be relevant for the inflammatory etiology of keratoconus. In conclusion, in the case of some first degree family members, the elevated tear biomarkers may represent a supplementary risk factor.


Assuntos
Ceratocone/metabolismo , Adolescente , Adulto , Quimiocina CCL5/metabolismo , Estudos Transversais , Feminino , Humanos , Interferon gama/metabolismo , Interleucina-10/metabolismo , Interleucina-4/metabolismo , Interleucina-6/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fator de Necrose Tumoral alfa/metabolismo , Adulto Jovem
6.
Gastric Cancer ; 20(6): 948-959, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28299464

RESUMO

BACKGROUND: Keratin 17 (KRT17) was shown to be an important molecular marker for predicting the carcinogenesis, progression, and prognosis of various cancer types. Our previous studies identified KRT17 as a possible biomarker for gastric cancer by gene microarray, with an elevated expression that occurred early during tumorigenesis and increased during tumor progression. Based on these findings, we aimed to investigate KRT17 biological functions in gastric adenocarcinoma and its possible use as a rational molecular target for anticancer therapy. METHODS: We used RNA interference-mediated knockdown of KRT17 expression and analyzed the effects on cell proliferation, cell migration, and signal transduction in two gastric cell lines (AGS and NCI-N87) in vitro and on xenograft growth in vivo. RESULTS: The functional analysis of KRT17 knockdown cell lines showed a decreased cell proliferation (with 42.36% ± 3.2%) and migration ability (with 37.2% ± 6.2%) relative to scrambled siRNA control. The in vivo tumorigenicity on nude mice exhibited a significant decrease in tumor weight with 69.14% in xenografts obtained from AGS cells and 84.43% in xeno-NCI-N87 tumors. The analysis on KRT17 knockdown outcome on intracellular signaling identifies AKT/mTOR as the main affected pathway that sustains proliferation and survival, and also the AMPKα1/CREB pathway that was recently shown to induce organ protection and antiinflammatory response. CONCLUSIONS: Our results highlight KRT17 as a possible biomarker in gastric cancer promoting tumor growth, motility, and invasion, and suggest that KRT17 can be a valuable molecular target for development of anti-gastric cancer-specific therapies.


Assuntos
Adenocarcinoma/patologia , Biomarcadores Tumorais/análise , Queratina-17/metabolismo , Neoplasias Gástricas/patologia , Adenocarcinoma/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Técnicas de Inativação de Genes , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , RNA Interferente Pequeno , Neoplasias Gástricas/metabolismo
7.
Mol Cell Biochem ; 410(1-2): 165-74, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26335900

RESUMO

Telocytes (TCs) are a novel cell type identified among interstitial cells in various organs. TCs are characterized by very long cell processes (tens to hundreds micrometres) named telopodes (Tps) with uneven calibre: dilations (podoms) and very thin segments (podomers). However, little is known about the factors which influence Tps conformation. Recently, extracellular matrix proteins were found to influence Tps extension, adherence and spreading. Here, we show that oxidative stress and ageing influence formation of new Tps of TCs cultivated from human non-pregnant myometrium. Using real-time videomicroscopy, we found that ageing the TCs to passage 21 increased the ratio of Tps/TC number with about 50 %, whereas oxidative stress hindered formation of new Tps in both aged and young TCs (passage 7). Under oxidative stress, newly formed cell processes were up to 25 % shorter. Migration pathway length was decreased by 30-40 % for both young and aged cells in an oxidative stress environment. Contrary, addition of N-acetyl cysteine in cell culture medium shifted TCs morphology to a long and slender profile. In conclusion, we showed that TCs specific morphology in vitro is influenced by oxidative status balance, as well as ageing.


Assuntos
Senescência Celular , Miométrio/metabolismo , Estresse Oxidativo , Telócitos/metabolismo , Telopódios/metabolismo , Antioxidantes/farmacologia , Movimento Celular , Proliferação de Células , Forma Celular , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Humanos , Microscopia de Vídeo , Miométrio/citologia , Miométrio/efeitos dos fármacos , Oxidantes/farmacologia , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Telócitos/efeitos dos fármacos , Telopódios/efeitos dos fármacos , Fatores de Tempo
8.
Future Oncol ; 11(3): 511-24, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25241806

RESUMO

An important goal of oncology is the development of cancer risk-identifier biomarkers that aid early detection and target therapy. High-throughput profiling represents a major concern for cancer research, including brain tumors. A promising approach for efficacious monitoring of disease progression and therapy could be circulating biomarker panels using molecular proteomic patterns. Tailoring treatment by targeting specific protein-protein interactions and signaling networks, microRNA and cancer stem cell signaling in accordance with tumor phenotype or patient clustering based on biomarker panels represents the future of personalized medicine for brain tumors. Gathering current data regarding biomarker candidates, we address the major challenges surrounding the biomarker field of this devastating tumor type, exploring potential perspectives for the development of more effective predictive biomarker panels.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/tratamento farmacológico , Terapia de Alvo Molecular , Biomarcadores/sangue , Biomarcadores/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/sangue , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Humanos , MicroRNAs/sangue , MicroRNAs/genética , Células Neoplásicas Circulantes/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Proteoma , Proteômica , Transdução de Sinais/efeitos dos fármacos
9.
Proteome Sci ; 12(1): 47, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25298751

RESUMO

BACKGROUND: The rapid progress of proteomics over the past years has allowed the discovery of a large number of potential biomarker candidates to improve early tumor diagnosis and therapeutic response, thus being further integrated into clinical environment. High grade gliomas represent one of the most aggressive and treatment-resistant types of human brain cancer, with approximately 9-12 months median survival rate for patients with grade IV glioma (glioblastoma). Using state-of-the-art proteomics technologies, we have investigated the proteome profile for glioblastoma patients in order to identify a novel protein biomarker panel that could discriminate glioblastoma patients from controls and increase diagnostic accuracy. RESULTS: In this study, SELDI-ToF MS technology was used to screen potential protein patterns in glioblastoma patients serum; furthermore, LC-MS/MS technology was applied to identify the candidate biomarkers peaks. Through these proteomic approaches, three proteins S100A8, S100A9 and CXCL4 were selected as putative biomarkers and confirmed by ELISA. Next step was to validate the above mentioned molecules as biomarkers through identification of protein expression by Western blot in tumoral versus peritumoral tissue. CONCLUSIONS: Proteomic technologies have been used to investigate the protein profile of glioblastoma patients and established several potential diagnostic biomarkers. While it is unlikely for a single biomarker to be highly effective for glioblastoma diagnostic, our data proposed an alternative and efficient approach by using a novel combination of multiple biomarkers.

10.
Curr Proteomics ; 10(3): 246-260, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24228024

RESUMO

High grade gliomas represent one of the most aggressive and treatment-resistant types of human cancer, with only 1-2 years median survival rate for patients with grade IV glioma. The treatment of glioblastoma is a considerable therapeutic challenge; combination therapy targeting multiple pathways is becoming a fast growing area of research. This review offers an up-to-date perspective of the literature about current molecular therapy targets in high grade glioma, that include angiogenic signals, tyrosine kinase receptors, nodal signaling proteins and cancer stem cells related approaches. Simultaneous identification of proteomic signatures could provide biomarker panels for diagnostic and personalized treatment of different subsets of glioblastoma. Personalized medicine is starting to gain importance in clinical care, already having recorded a series of successes in several types of cancer; nonetheless, in brain tumors it is still at an early stage.

11.
Gels ; 9(1)2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36661817

RESUMO

In vitro tumor spheroids have proven to be useful 3D tumor culture models for drug testing, and determining the molecular mechanism of tumor progression and cellular interactions. Therefore, there is a continuous search for their industrial scalability and routine preparation. Considering that hydrogels are promising systems that can favor the formation of tumor spheroids, our study aimed to investigate and develop less expensive and easy-to-use amorphous and crosslinked hydrogels, based on natural compounds such as sodium alginate (NaAlg), aloe vera (AV) gel powder, and chitosan (CS) for tumor spheroid formation. The ability of the developed hydrogels to be a potential spheroid-forming system was evaluated using MDA-MB-231 and U87MG cancer cells. Spheroid abilities were influenced by pH, viscosity, and crosslinking of the hydrogel. Addition of either AV or chitosan to sodium alginate increased the viscosity at pH 5, resulting in amorphous hydrogels with a strong gel texture, as shown by rheologic analysis. Only the chitosan-based gel allowed formation of spheroids at pH 5. Among the variants of AV-based amorphous hydrogels tested, only hydrogels at pH 12 and with low viscosity promoted the formation of spheroids. The crosslinked NaAlg/AV, NaAlg/AV/glucose, and NaAlg/CS hydrogel variants favored more efficient spheroid formation. Additional studies would be needed to use AV in other physical forms and other formulations of hydrogels, as the current study is an initiation, in evaluating the potential use of AV gel in tumor spheroid formation systems.

12.
Gels ; 9(6)2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37367146

RESUMO

Healthcare professionals face an ongoing challenge in managing both acute and chronic wounds, given the potential impact on patients' quality of life and the limited availability of expensive treatment options. Hydrogel wound dressings offer a promising solution for effective wound care due to their affordability, ease of use, and ability to incorporate bioactive substances that enhance the wound healing process. Our study aimed to develop and evaluate hybrid hydrogel membranes enriched with bioactive components such as collagen and hyaluronic acid. We utilized both natural and synthetic polymers and employed a scalable, non-toxic, and environmentally friendly production process. We conducted extensive testing, including an in vitro assessment of moisture content, moisture uptake, swelling rate, gel fraction, biodegradation, water vapor transmission rate, protein denaturation, and protein adsorption. We evaluated the biocompatibility of the hydrogel membranes through cellular assays and performed instrumental tests using scanning electron microscopy and rheological analysis. Our findings demonstrate that the biohybrid hydrogel membranes exhibit cumulative properties with a favorable swelling ratio, optimal permeation properties, and good biocompatibility, all achieved with minimal concentrations of bioactive agents.

13.
Pharmaceutics ; 15(12)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38140037

RESUMO

Complicated wounds often require specialized medical treatments, and hydrogels have emerged as a popular choice for wound dressings in such cases due to their unique properties and the ability to incorporate and release therapeutic agents. Our focus was to develop and characterize a new optimized formula for biohybrid hydrogel membranes, which combine natural and synthetic polymers, bioactive natural compounds, like collagen and hyaluronic acid, and pharmacologically active substances (doxycycline or npAg). Dynamic (oscillatory) rheometry confirmed the strong gel-like properties of the obtained hydrogel membranes. Samples containing low-dose DOXY showed a swelling index of 285.68 ± 6.99%, a degradation rate of 71.6 ± 0.91% at 20 h, and achieved a cumulative drug release of approximately 90% at pH 7.4 and 80% at pH 8.3 within 12 h. The addition of npAg influenced the physical properties of the hydrogel membranes. Furthermore, the samples containing DOXY demonstrated exceptional antimicrobial efficacy against seven selected bacterial strains commonly associated with wound infections and complications. Biocompatibility assessments revealed that the samples exhibited over 80% cell viability. However, the addition of smaller-sized nanoparticles led to decreased cellular viability. The obtained biohybrid hydrogel membranes show favorable properties that render them suitable for application as wound dressings.

14.
Mol Biol Rep ; 39(3): 2243-52, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21643950

RESUMO

microRNAs are short, non-coding RNAs, that exert a posttranscriptional control on protein synthesis by mRNA interference. They are involved in normal and pathological embryologic development, as well as in adult life pathology, from myocardial infarction to cancer. There are several brain-specific species of microRNA, showing time-dependent pattern of expression, selectivity for neuronal population, significant roles in correct cellular differentiation and system development. The growing interest in microRNAs extended also in the area of neurodegeneration, some of brain-restricted microRNAs being reported to associate with disorders such as Alzheimer's disease, Parkinson's disease or Huntington's disease. The microRNAs research in the last 3 years offered a considerable amount of information that needs to be integrated in the vast machinery of cellular biology.


Assuntos
Sistema Nervoso Central/embriologia , Regulação da Expressão Gênica no Desenvolvimento/genética , MicroRNAs/biossíntese , MicroRNAs/genética , Modelos Biológicos , Doenças Neurodegenerativas/metabolismo , Sistema Nervoso Central/metabolismo , Humanos
15.
Metabolites ; 12(4)2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35448516

RESUMO

Fatty acids (FAs) have been shown to exhibit a pro-inflammatory response in various cell types, but astrocytes have been mostly overlooked. FAs, both saturated and unsaturated, have previously been shown to induce pro-inflammatory responses in astrocytes at high concentrations of hundreds of µg/mL. SSO (Sulfo-N-succinimidyl Oleate sodium), an inhibitor of FA translocase CD36, has been shown to prevent inflammation in the mouse brain by acting on local microglia and infiltrating monocytes. Our hypothesis was that SSO treatment would also impact astrocyte pro-inflammatory response to FA. In order to verify our assumption, we evaluated the expression of pro- and anti-inflammatory cytokines in normal human astrocyte cell culture pre-treated (or not) with SSO, and then exposed to low concentrations of both saturated (palmitic acid) and unsaturated (oleic acid) FAs. As a positive control for astrocyte inflammation, we used fibrillary amyloid. Neither Aß 1-42 nor FAs induced CD36 protein expression in human astrocytes in cell culture At low concentrations, both types of FAs induced IL-8 protein secretion, and this effect was specifically inhibited by SSO pre-treatment. In conclusion, low concentrations of oleic acid are able to induce an early increase in IL-8 expression in normal human astrocytes, which is specifically downregulated by SSO.

16.
Micromachines (Basel) ; 13(10)2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36296024

RESUMO

The selective and rapid detection of tumor cells is of critical consequence for the theragnostic field of tumorigenesis; conventional methods, such as histopathological diagnostic methods, often require a long analysis time, excessive analytical costs, complex operations, qualified personnel and deliver many false-positive results. We are considering a new approach of an electrochemical biosensor based on graphene, which is evidenced to be a revolutionary nanomaterial enabling the specific and selective capture of tumor cells. In this paper, we report a biosensor fabricated by growing vertically aligned graphene nanosheets on the conductive surface of interdigitated electrodes which is functionalized with anti-EpCAM antibodies. The dielectric signature of the three types of tumor cells is determined by correlating the values from the Nyquist and Bode diagram: charge transfer resistance, electrical double layer capacity, Debye length, characteristic relaxation times of mobile charges, diffusion/adsorption coefficients, and variation in the electrical permittivity complex and of the phase shift with frequency. These characteristics are strongly dependent on the type of membrane molecules and the electromagnetic resonance frequency. We were able to use the fabricated sensor to differentiate between three types of tumor cell lines, HT-29, SW403 and MCF-7, by dielectric signature. The proposed evaluation method showed the permittivity at 1 MHz to be 3.63 nF for SW403 cells, 4.97 nF for HT 29 cells and 6.9 nF for MCF-7 cells.

17.
Gels ; 8(10)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36286105

RESUMO

The study and discovery of bioactive compounds and new formulations as potential tools for promoting the repair of dermoepidermal tissue in wound healing is of continuing interest. We have developed a new formulation of amorphous hydrogel based on sodium alginate (NaAlg); type I collagen, isolated by the authors from silver carp tails (COL); glycerol (Gli); Aloe vera gel powder (AV); and silver nanoparticles obtained by green synthesis with aqueous Cinnamomum verum extract (AgNPs@CIN) and vitamin C, respectively. The gel texture of the amorphous hydrogels was achieved by the addition of Aloe vera, demonstrated by a rheological analysis. The evaluations of the cytotoxicity and cell proliferation capacity of the experimental amorphous hydrogels were performed against human foreskin fibroblast Hs27 cells (CRL-1634-ATCC). The developed gel formulations did not show a cytotoxic effect. The hydrogel variant containing AgNPs@CIN in a concentration of 8 µg Ag/gel formulation and hydrogel variant with vitamin C had proliferative activity. In addition, the antibacterial activity of the hydrogels was evaluated against S. aureus ATCC 6538, Ps. aeruginosa ATCC 27853, and E. coli ATCC 25922. The results demonstrated that the gel variant based on AgNPs@CIN in a concentration of 95 µg Ag/gel formulation and the hydrogel based on vitamin C show antibacterial activity. Therefore, the developed hydrogels with AgNPs@CIN and vitamin C could be promising alternatives in wound healing.

18.
Neuroscience ; 453: 301-311, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33212223

RESUMO

CD36 is a membrane protein with wide distribution in the human body, is enriched in the monocyte-macrophage system and endothelial cells, and is involved in the cellular uptake of long chain fatty acids (LCFA) and oxidized low-density lipoproteins. It is also a scavenger receptor, binding hydrophobic amyloid fibrils found in the Alzheimer's disease (AD) brain. In neurobiology research, it has been mostly studied in relationship with chronic ischemia and stroke, but it was also related to amyloid clearance by microglial phagocytosis. In AD animal models, amyloid binding to CD36 has been consistently correlated with a pro-inflammatory response. Therapeutic approaches have two main focuses: CD36 blockade with monoclonal antibodies or small molecules, which is beneficial in terms of the inflammatory milieu, and upregulation of CD36 for increased amyloid clearance. The balance of the two approaches, centered on microglia, is poorly understood. Furthermore, CD36 evaluation in AD clinical studies is still at a very early stage and there is a gap in the knowledge regarding the impact of LCFA on AD progression and CD36 expression and genetic phenotype. This review summarizes the role played by CD36 in the pathogenic amyloid cascade and explore the translatability of preclinical data towards clinical research.


Assuntos
Doença de Alzheimer , Antígenos CD36 , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Animais , Células Endoteliais/metabolismo , Humanos , Microglia/metabolismo
19.
Front Pharmacol ; 12: 723233, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34552489

RESUMO

Due to the increasing prevalence of life-threatening bacterial, fungal and viral infections and the ability of these human pathogens to develop resistance to current treatment strategies, there is a great need to find and develop new compunds to combat them. These molecules must have low toxicity, specific activity and high bioavailability. The most suitable compounds for this task are usually derived from natural sources (animal, plant or even microbial). In this review article, the latest and most promising natural compounds used to combat bacteria, filamentous fungi and viruses are presented and evaluated. These include plant extracts, essential oils, small antimicrobial peptides of animal origin, bacteriocins and various groups of plant compounds (triterpenoids; alkaloids; phenols; flavonoids) with antimicrobial and antiviral activity. Data are presented on the inhibitory activity of each natural antimicrobial substance and on the putative mechanism of action against bacterial and fungal strains. The results show that among the bioactive compounds studied, triterpenoids have significant inhibitory activity against coronaviruses, but flavonoids have also been shown to inhibit SARS-COV-2. The last chapter is devoted to nanocarriers used to improve stability, bioavailability, cellular uptake/internalization, pharmacokinetic profile and reduce toxicity of natural compunds. There are a number of nanocarriers such as liposomes, drug delivery microemulsion systems, nanocapsules, solid lipid nanoparticles, polymeric micelles, dendrimers, etc. However, some of the recent studies have focused on the incorporation of natural substances with antimicrobial/antiviral activity into polymeric nanoparticles, niosomes and silver nanoparticles (which have been shown to have intrinsic antimicrobial activity). The natural antimicrobials isolated from animals and microorganisms have been shown to have good inhibitory effect on a range of pathogens, however the plants remain the most prolific source. Even if the majority of the studies for the biological activity evaluation are in silico or in vitro, their internalization in the optimum nanocarriers represents the future of "green therapeutics" as shown by some of the recent work in the field.

20.
J Pers Med ; 11(4)2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33917064

RESUMO

Past decades demonstrate an increasing interest in herbal remedies in the public eye, with as many as 80% of people worldwide using these remedies as healthcare products, including those for skin health. Sea buckthorn and its derived products (oil; alcoholic extracts), rich in flavonoids and essential fatty acids, are among these healthcare products. Specifically, sea buckthorn and its derivatives are reported to have antioxidant and antitumor activity in dysplastic skin cells. On the other hand, evidence suggests that the alteration of lipid metabolism is related to increased malignant behavior. Given the paradoxical involvement of lipids in health and disease, we investigated how sea-buckthorn seed oil, rich in long-chain fatty acids, modifies the proliferation of normal and dysplastic skin cells in basal conditions, as well as under ultraviolet A (UVA) radiation. Using real-time analysis of normal and dysplastic human keratinocytes, we showed that sea-buckthorn seed oil stimulated the proliferation of dysplastic cells, while it also impaired the ability of both normal and dysplastic cells to migrate over a denuded area. Furthermore, UVA exposure increased the expression of CD36/SR-B2, a long-chain fatty acid translocator that is related to the metastatic behavior of tumor cells.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA