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1.
Int J Mol Sci ; 25(2)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38255969

RESUMO

Cystic fibrosis (CF) is a genetic disease that causes dehydration of the surface of the airways, increasing lung infections, most frequently caused by Pseudomonas aeruginosa. Exosomes are nanovesicles released by cells that play an essential role in intercellular communication, although their role during bacterial infections is not well understood. In this article, we analyze the alterations in exosomes produced by healthy bronchial epithelial and cystic fibrosis cell lines caused by the interaction with P. aeruginosa. The proteomic study detected alterations in 30% of the species analyzed. In healthy cells, they mainly involve proteins related to the extracellular matrix, cytoskeleton, and various catabolic enzymes. In CF, proteins related to the cytoskeleton and matrix, in addition to the proteasome. These differences could be related to the inflammatory response. A study of miRNAs detected alterations in 18% of the species analyzed. The prediction of their potential biological targets identified 7149 genes, regulated by up to 7 different miRNAs. The identification of their functions showed that they preferentially affected molecules involved in binding and catalytic activities, although with differences between cell types. In conclusion, this study shows differences in exosomes between CF and healthy cells that could be involved in the response to infection.


Assuntos
Fibrose Cística , Exossomos , MicroRNAs , Infecções por Pseudomonas , Humanos , Pseudomonas aeruginosa , Fibrose Cística/genética , Proteômica , MicroRNAs/genética
2.
Int J Mol Sci ; 24(7)2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37047483

RESUMO

PTEN-induced kinase-1 (PINK1) is the initiator of the canonical mitophagy pathway. Our aim was to study the immunoexpression of PINK1 in surgical specimens from ninety patients with metastatic colorectal adenocarcinoma (CRC) to the liver (CRLM). Tissue arrays were produced, and immunohistochemical studies were analyzed by the H-Score method. The mean immunoexpression of PINK1 in normal tissues was between 40 to 100 points. In tumoral tissues, positive PINK1 immunoexpression was observed in all samples, and no differences were noted between CRCs. In CRLMs, a significant under-expression was noted for PINK1 from the rectum (71.3 ± 30.8; p < 0.042) compared to other sites. Altered PINK1 immunoexpression in CRCs, either higher than 100 points or lower than 40 points, was associated with worse overall survival (OS) (p < 0.012) due to a shorter post-metastatic survival (PMS) (p < 0.023), and it was found to be a significant independent predictor of prognosis in a multivariate model for OS and PMS (HR = 1.972, 95% CI 0.971-4.005; p = 0.022. HR = 2.023, 95% CI 1.003-4.091; p = 0.037, respectively). In conclusion, altered PINK1 immunoexpression determined in CRCs with resected CRLM predicts a worse prognosis, possibly due to the abnormal function of mitophagy.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Hepatectomia , Estudos Retrospectivos , Neoplasias Hepáticas/secundário , Neoplasias Colorretais/genética , Neoplasias Colorretais/cirurgia , Proteínas Quinases/genética
3.
BMC Microbiol ; 22(1): 65, 2022 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-35219289

RESUMO

BACKGROUND: Cell surface glycosaminoglycans (GAGs) participate in many physiological and pathological processes, including infections and inflammatory response. Acne is a common chronic inflammatory skin disorder that affects the pilosebaceous unit and has a multifactorial etiology, including bacterial colonization of the hair follicle. This study aimed to investigate the participation of GAG in the adhesion of Propionibacterium acnes, Staphylococcus aureus and Staphylococcus epidermidis to keratinocytes and fibroblasts of the skin by competition experiments and cell surface removal using specific liases. The alteration in the transcription of the genes responsible for the synthesis of GAG induced by the adhesion of these bacteria was also analyzed by qRT-PCR. RESULTS: GAGs are involved in bacterial adherence to skin cells, especially fibroblasts, where chondroitin sulfate displayed the higher effect. Bacterial adherence produced different alterations in the transcription of the genes responsible for GAG structures. P. acnes induced mostly changes in keratinocytes, while S. epidermidis was the main cause of alterations in fibroblasts. These variations in gene expression affected all the stages in the biosynthesis of the main species of GAGs, heparan and chondroitin sulphate. CONCLUSIONS: GAGs species are involved in the adhesion of acne-related bacteria to skin cells in a differential manner depending on each microorganism and cellular type, although other receptors seem to exist. Bacterial adherence led to variations on gene expression in skin cells affecting GAG chains structure what, consequently, should alter their interactions with different ligands, affecting the development of acne disease.


Assuntos
Acne Vulgar , Glicosaminoglicanos , Bactérias/metabolismo , Sulfatos de Condroitina/metabolismo , Glicosaminoglicanos/metabolismo , Humanos , Complexo Glicoproteico GPIb-IX de Plaquetas
4.
BMC Microbiol ; 20(1): 172, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32560673

RESUMO

BACKGROUND: The emergence and expansion of antibiotic resistance makes it necessary to have alternative anti-infective agents, among which silver nanoparticles (AgNPs) display especially interesting properties. AgNPs carry out their antibacterial action through various molecular mechanisms, and the magnitude of the observed effect is dependent on multiple, not fully understood, aspects, particle shape being one of the most important. In this article, we conduct a study of the antibacterial effect of a recently described type of AgNP: silver nanorings (AgNRs), making comparisons with other alternative types of AgNP synthesized in parallel using the same methodology. RESULTS: When they act on planktonic forms, AgNRs produce a smaller effect on the viability of different bacteria than nanoparticles with other structures although their effect on growth is more intense over a longer period. When their action on biofilms is analyzed, AgNRs show a greater concentration-dependent effect. In both cases it was observed that the effect on inhibition depends on the microbial species, but not its Gram positive or negative nature. Growth patterns in silver-resistant Salmonella strains suggest that AgNRs work through different mechanisms to other AgNPs. The antibacterial effect is also produced to some extent by the conditioning of culture media or water by contact with AgNPs but, at least over short periods of time, this is not due to the release of Ag ions. CONCLUSIONS: AgNRs constitute a new type of AgNP, whose antibacterial properties depend on their shape, and is capable of acting efficiently on both planktonic bacteria and biofilms.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Salmonella/crescimento & desenvolvimento , Prata/farmacologia , Antibacterianos/química , Meios de Cultivo Condicionados/química , Relação Dose-Resposta a Droga , Composição de Medicamentos , Farmacorresistência Bacteriana/efeitos dos fármacos , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Nanoestruturas , Salmonella/efeitos dos fármacos , Prata/química
5.
BMC Cancer ; 18(1): 687, 2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-29940912

RESUMO

BACKGROUND: Heparan sulfate proteoglycans (HSPGs) are complex molecules which play a role in the invasion and growth and metastatic properties of cancerous cells. In this work we analyze changes in the patterns of expression of HSPGs in left sided colorectal cancer (LSCRC), both metastatic and non-metastatic, and the results are also compared with those previously obtained for right sided tumors (RSCRCs). METHODS: Eighteen LSCRCs were studied using qPCR to analyze the expression of both the proteoglycan core proteins and the enzymes involved in heparan sulfate chain biosynthesis. Certain HSPGs also carry chondroitin sulfate chains and so we also studied the genes involved in its biosynthesis. The expression of certain genes that showed significant expression differences were also analysed using immunohistochemical techniques. RESULTS: Changes in proteoglycan core proteins were dependent on their location, and the main differences between metastatic and non-metastatic tumors affected cell-surface glypicans, while other molecules were quite similar. Glypicans were also responsible for the main differences between RS- and LS- malignances. Regarding the biosynthesis of heparan sulfate chains, differential alterations in transcription depending on the presence or not of metastasis affected genes involved in the modification of uronic acid (epimerization and 2-O sulfation), and some isoforms responsible for sulfation of glucosamine (NDST1, HS6ST1). Moreover, in RSCRCs differences were preferentially found in the expression of genes involved in C6 and C3 sulfation of glucosamine, but not in NDSTs or SULFs. Finally, synthesis of chondroitin sulfate showed some alterations, which affected various steps, including polimerization and the modification of chains, but the main variations dependent on the presence of metastases were epimerization and 6C sulfation; however, when compared with RSCRCs, the essential divergences affected polymerization of the chains and the 6C sulfation of the galactosamine residue. CONCLUSIONS: We evidenced alterations in the expression of HSPGs, including the expression of cell surface core proteins, many glycosiltransferases and some enzymes that modify the GAG chains in LSCRCs, but this was dependent on the metastatic nature of the tumor. Some of these alterations are shared with RSCRCs, while others, focused on specific gene groups, are dependent on tumor localization.


Assuntos
Neoplasias Colorretais/patologia , Proteoglicanas de Heparan Sulfato/genética , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/mortalidade , Feminino , Glicosiltransferases/genética , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias
6.
BMC Infect Dis ; 17(1): 319, 2017 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-28464847

RESUMO

BACKGROUND: Lower respiratory infections are among the top ten causes of death worldwide. Since pathogen to cell adhesion is a crucial step in the infection progress, blocking the interaction between eukaryotic receptors and bacterial ligands may enable the pathogenesis process to be stopped. Cell surface glycosaminoglycans (GAGs) are known to be mediators in the adhesion of diverse bacteria to different cell types, making it of interest to examine their involvement in the attachment of various pathogenic bacteria to lung cells, including epithelial cells and fibroblasts. METHODS: The function of cell surface GAGs in bacterial adhesion was studied by reducing their levels through inhibiting their biosynthesis and enzymatic degradation, as well as in binding competition experiments with various species of GAGs. The participation of the different bacterial adhesins in attachment was evaluated through competition with two peptides, both containing consensus heparin binding sequences. Blocking inhibition assays using anti-syndecans and the enzymatic removal of glypicans were conducted to test their involvement in bacterial adhesion. The importance of the fine structure of GAGs in the interaction with pathogens was investigated in competition experiments with specifically desulfated heparins. RESULTS: The binding of all bacteria tested decreased when GAG levels in cell surface of both lung cells were diminished. Competition experiments with different types of GAGs showed that heparan sulfate chains are the main species involved. Blocking or removal of cell surface proteoglycans evidenced that syndecans play a more important role than glypicans. The binding was partially inhibited by peptides including heparin binding sequences. Desulfated heparins also reduced bacterial adhesion to different extents depending on the bacterium and the sulfated residue, especially in fibroblast cells. CONCLUSIONS: Taken together, these data demonstrate that the GAG chains of the cell surface are involved in the adhesion of bacterial adhesins to lung cells. Heparan sulfate seems to be the main species implicated, and binding is dependent on the sulfation pattern of the molecule. These data could facilitate the development of new anti-infective strategies, enabling the development of new procedures for blocking the interaction between pathogens and lung cells more effectively.


Assuntos
Aderência Bacteriana/fisiologia , Glicosaminoglicanos/metabolismo , Bactérias Gram-Positivas/patogenicidade , Linhagem Celular , Células Epiteliais/microbiologia , Fibroblastos/microbiologia , Heparina/metabolismo , Heparitina Sulfato/metabolismo , Humanos , Pulmão/citologia , Pulmão/microbiologia , Proteoglicanas/metabolismo
7.
Antimicrob Agents Chemother ; 59(1): 677-81, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25331698

RESUMO

Enzymatic elimination of surface glycosaminoglycans or inhibition of their sulfation provokes sensitizing of HT-29 and HeLa cells toward the peptide bacteriocins nisin A, plantaricin C, and pediocin PA-1/AcH. The effect can be partially reversed by heparin, which also lowers the susceptibility of Lactococcus lactis to nisin A. These data indicate that the negative charge of the glycosaminoglycan sulfate residues binds the positively charged bacteriocins, thus protecting eukaryotic cells from plasma membrane damage.


Assuntos
Bacteriocinas/farmacologia , Glicosaminoglicanos/fisiologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/fisiologia , Células HT29/efeitos dos fármacos , Células HT29/fisiologia , Células HeLa/efeitos dos fármacos , Células HeLa/fisiologia , Heparina/farmacologia , Humanos , Lactococcus lactis/metabolismo , Nisina/farmacologia , Pediocinas
8.
BMC Cancer ; 15: 742, 2015 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-26482785

RESUMO

BACKGROUND: Heparan sulfate proteoglycans (HSPGs) are complex molecules involved in the growth, invasion and metastatic properties of cancerous cells. This study analyses the alterations in the expression patterns of these molecules in right sided colorectal cancer (CRC), both metastatic and non-metastatic. METHODS: Twenty right sided CRCs were studied. A transcriptomic approach was used, employing qPCR to analyze both the expression of the enzymes involved in heparan sulfate (HS) chains biosynthesis, as well as the proteoglycan core proteins. Since some of these proteoglycans can also carry chondroitin sulfate (CS) chains, we include the study of the genes involved in the biosynthesis of these glycosaminoglycans. Immunohistochemical techniques were also used to analyze tissue expression of particular genes showing significant expression differences, of potential interest. RESULTS: Changes in proteoglycan core proteins differ depending on their location; those located intracellularly or in the extracellular matrix show very similar alteration patterns, while those located on the cell surface vary greatly depending on the nature of the tumor: glypicans 1, 3, 6 and betaglycan are affected in the non-metastatic tumors, whereas in the metastatic, only glypican-1 and syndecan-1 are modified, the latter showing opposing alterations in levels of RNA and of protein, suggesting post-transcriptional regulation in these tumors. Furthermore, in non-metastatic tumors, polymerization of glycosaminoglycan chains is modified, particularly affecting the synthesis of the tetrasaccharide linker and the initiation and elongation of CS chains, HS chains being less affected. Regarding the enzymes responsible for the modificaton of the HS chains, alterations were only found in non-metastatic tumors, affecting N-sulfation and the isoforms HS6ST1, HS3ST3B and HS3ST5. In contrast, synthesis of the CS chains suggests changes in epimerization and sulfation of the C4 and C2 in both types of tumor. CONCLUSIONS: Right sided CRCs show alterations in the expression of HSPGs, including the expression of the cell surface core proteins, many glycosiltransferases and some enzymes that modify the HS chains depending on the metastatic nature of the tumor, resulting more affected in non-metastatic ones. However, matrix proteoglycans and enzymes involved in CS fine structure synthesis are extensively modified independetly of the presence of lymph node metastasis.


Assuntos
Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Proteoglicanas de Heparan Sulfato/genética , RNA Neoplásico/genética , Idoso , Animais , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/secundário , Feminino , Proteoglicanas de Heparan Sulfato/biossíntese , Humanos , Imuno-Histoquímica , Masculino , Metástase Neoplásica , Reação em Cadeia da Polimerase em Tempo Real , Células Tumorais Cultivadas
9.
BMC Microbiol ; 13: 210, 2013 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-24044741

RESUMO

BACKGROUND: The adhesion of lactobacilli to the vaginal surface is of paramount importance to develop their probiotic functions. For this reason, the role of HeLa cell surface proteoglycans in the attachment of Lactobacillus salivarius Lv72, a mutualistic strain of vaginal origin, was investigated. RESULTS: Incubation of cultures with a variety of glycosaminoglycans (chondroitin sulfate A and C, heparin and heparan sulfate) resulted in marked binding interference. However, no single glycosaminoglycan was able to completely abolish cell binding, the sum of all having an additive effect that suggests cooperation between them and recognition of specific adhesins on the bacterial surface. In contrast, chondroitin sulfate B enhanced cell to cell attachment, showing the relevance of the stereochemistry of the uronic acid and the sulfation pattern on binding. Elimination of the HeLa surface glycosaminoglycans with lyases also resulted in severe adherence impairment. Advantage was taken of the Lactobacillus-glycosaminoglycans interaction to identify an adhesin from the bacterial surface. This protein, identify as a soluble binding protein of an ABC transporter system (OppA) by MALDI-TOF/(MS), was overproduced in Escherichia coli, purified and shown to interfere with L. salivarius Lv72 adhesion to HeLa cells. CONCLUSIONS: These data suggest that glycosaminoglycans play a fundamental role in attachment of mutualistic bacteria to the epithelium that lines the cavities where the normal microbiota thrives, OppA being a bacterial adhesin involved in the process.


Assuntos
Adesinas Bacterianas/metabolismo , Aderência Bacteriana , Células Epiteliais/química , Células Epiteliais/microbiologia , Glicosaminoglicanos/metabolismo , Lactobacillus/fisiologia , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Adesinas Bacterianas/genética , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Escherichia coli/genética , Feminino , Expressão Gênica , Células HeLa , Humanos , Lactobacillus/isolamento & purificação
10.
BMC Cancer ; 13: 24, 2013 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-23327652

RESUMO

BACKGROUND: The expression of a specific set of genes controls the different structures of heparan sulfate proteoglycans (HSPGs), which are involved in the growth, invasion and metastatic properties of cancerous cells. The purpose of this study is to increase knowledge of HSPG alterations in breast cancer. METHODS: Twenty-three infiltrating ductal adenocarcinomas (IDCs), both metastatic and non-metastatic were studied. A transcriptomic approach to the structure of heparan sulfate (HS) chains was used, employing qPCR to analyze both the expression of the enzymes involved in their biosynthesis and editing, as well as the proteoglycan core proteins. Since some of these proteoglycans can also carry chondroitin sulfate chains, we extended the study to include the genes involved in the biosynthesis of these glycosaminoglycans. Histochemical techniques were also used to analyze tissular expression of particular genes showing significant expression differences, of potential interest. RESULTS: No significant change in transcription was detected in approximately 70% of analyzed genes. However, 13 demonstrated changes in both tumor types (40% showing more intense deregulation in the metastatic), while 5 genes showed changes only in non-metastatic tumors. Changes were related to 3 core proteins: overexpression of syndecan-1 and underexpression of glypican-3 and perlecan. HS synthesis was affected by lower levels of some 3-O-sulfotransferase transcripts, the expression of NDST4 and, only in non metastatic tumors, higher levels of extracellular sulfatases. Furthermore, the expression of chondroitin sulfate also was considerably affected, involving both the synthesis of the saccharidic chains and sulfations at all locations. However, the pro-metastatic enzyme heparanase did not exhibit significant changes in mRNA expression, although in metastatic tumors it appeared related to increased levels of the most stable form of mRNA. Finally, the expression of heparanase 2, which displays anti-metastatic features, experienced a strong deregulation in all patients analyzed. CONCLUSIONS: IDCs show alterations in the expression of HSPG genes; principally the expression and localization of proteoglycans and the sulfation patterns of glycosaminoglycan chains, depending on the metastatic nature of the tumor. In addition, the anti-proliferative molecule heparanase 2 experiences strong deregulation, thus highlighting it as a potentially interesting diagnostic factor.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteoglicanas de Heparan Sulfato/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/secundário , Sulfatos de Condroitina/metabolismo , Feminino , Perfilação da Expressão Gênica/métodos , Glucuronidase/genética , Glipicanas/genética , Proteoglicanas de Heparan Sulfato/metabolismo , Humanos , Imuno-Histoquímica , Proteínas de Membrana/genética , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , Sulfotransferases/genética , Sindecana-1/genética
11.
Pol J Microbiol ; 71(1): 55-62, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35635172

RESUMO

The most common causal agents of fungal keratitis are yeasts of the Candida genus. Adhesion constitutes the first stage of pathogenesis. Previous studies have shown that glycosaminoglycans from the corneal cell surface play an essential role in bacterial keratitis, although little is known about their role in fungal infections. The objective of this work is to analyze the role that glycosaminoglycans (GAGs) play in the adhesion of fungi of the Candida genus to corneal epithelial cells. The participation of GAGs in the adhesion of fungi was studied through the specific inhibition of the synthesis of these molecules by enzymatic digestion using specific lyases and the silencing of various genes involved in heparan sulfate sulfation. The results seem to indicate that glycosaminoglycans act to some extent as receptors for this fungus, although there are differences between fungal species. Treatment with inhibitors partially reduced the adherence of fungal species. Digestion of cell surface heparan sulfate further reduced the adherence of Candida albicans and Candida glabrata compared to chondroitin sulfate, indicating that the binding is preferentially mediated by heparan sulfate. Degradation of both heparan sulfate and chondroitin sulfate produced similar effects on the adherence of Candida parapsilosis. However, adhesion of C. albicans hyphae is not dependent on GAGs, suggesting the expression of other adhesins and the recognition of other receptors present in corneal cells. Our results open the door to new strategies for stopping the adhesion of pathogenic fungi, and their subsequent invasion of the cornea; thus, reducing the probability of the keratitis development.


Assuntos
Sulfatos de Condroitina , Glicosaminoglicanos , Candida/metabolismo , Candida albicans , Sulfatos de Condroitina/metabolismo , Córnea , Glicosaminoglicanos/metabolismo , Heparitina Sulfato/metabolismo
12.
Polymers (Basel) ; 14(22)2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36433048

RESUMO

(1) Background: Abnormal corneal wound healing compromises visual acuity and can lead to neuropathic pain. Conventional treatments usually fail to restore the injured corneal tissue. In this study, we evaluated the effectiveness of a synthetic heparan sulfate mimetic polymer (HSmP) in a mouse model of corneal wound healing. (2) Methods: A surgical laser ablation affecting the central cornea and subbasal nerve plexus of mice was used as a model of the wound-healing assay. Topical treatment with HSmP was contrasted to its vehicle and a negative control (BSS). Corneal repair was studied using immunofluorescence to cell proliferation (Ki67), apoptosis (TUNEL assay), myofibroblast transformation (αSMA), assembly of epithelial cells (E-cadherin) and nerve regeneration (ß-tubulin III). (3) Results: At the end of the treatment, normal epithelial cytoarchitecture and corneal thickness were achieved in HSmP-treated animals. HSmP treatment reduced myofibroblast occurrence compared to eyes irrigated with vehicle (p < 0.01) or BSS (p < 0.001). The HSmP group showed 50% more intraepithelial nerves than the BSS or vehicle groups. Only HSmP-treated corneas improved the visual quality to near transparent. (4) Conclusions: These results suggest that HSmP facilitates the regeneration of the corneal epithelium and innervation, as well as restoring transparency and reducing myofibroblast scarring after laser experimental injury.

13.
Antibiotics (Basel) ; 11(8)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-36009923

RESUMO

Silver nanoparticles (AgNPs) play an important role in the medical field due to their potent antimicrobial activity. This, together with the constant emergence of resistance to antimicrobial drugs, means AgNPs are often investigated as an alternative to solve this problem. In this article, we analyzed the antifungal and antiamoebic effects of a recently described type of AgNP, silver nanorings (AgNRs), and compared them with other types of AgNPs. Tests of the activity of AgNPs against various fungal and amoebic species were carried out. In all cases, AgNPs showed a high biocidal effect, although with fungi this depended on the species involved. Antifungal activity was detected by the conditioning of culture media or water but this effect was not dependent on the release of Ag ions. On the other hand, the proliferation of Acanthamoeba castellanii trophozoites was reduced by silver nanorings (AgNRs) and silver nanowires (AgNWs), with AgNWs being capable of totally inhibiting the germination of A. castellanii cysts. AgNRs constitute a new type of AgNP with an antifungal and antiacanthamoebic activity. These results open the door to new and effective antimicrobial therapies as an alternative to the use of antifungals or antiamoebic drugs, thus avoiding the constant appearance of resistance and the difficulty of eradicating infections.

14.
Biomedicines ; 10(10)2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36289615

RESUMO

Exosomes have been related to various disorders, but their study in relation to ocular pathologies has been limited. In this article, we analyze exosomes produced by corneal stromal cells from healthy individuals and from patients with keratoconus. The proteomic study allowed for the identification of 14 new proteins with altered expression, related to molecules previously associated with the pathology. miRNA analysis detected 16 altered species, including miR-184, responsible for familial severe keratoconus. The prediction of its potential biological targets identified 1121 genes, including some related to this pathology. Exosomes produced by keratoconic cells induced a marked increase in the migration of stromal cells and corneal epithelium, while those produced by healthy cells had no effect on stromal cells. Both types of nanovesicles reduced the proliferation of stromal and corneal cells, but those produced by healthy cells had less effect. Exosomes produced by healthy cells had concentration-dependent effects on the transcription of genes encoding proteoglycans by keratoconus cells, with a relative normalization observed at concentrations of 240 µg/mL. These results show the alteration of stromal exosomes in keratoconus and suggest an influence on the development of the pathology, although the use of healthy exosomes could also have therapeutic potential.

15.
Ocul Surf ; 23: 40-48, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34781021

RESUMO

PURPOSE: To describe the association between Sars-CoV-2 infection and small fiber neuropathy in the cornea identified by in vivo corneal confocal microscopy. METHODS: Twenty-three patients who had overcome COVID-19 were recruited to this observational retrospective study. Forty-six uninfected volunteers were also recruited and studied as a control group. All subjects were examined under in vivo confocal microscopy to obtain images of corneal subbasal nerve fibers in order to study the presence of neuroma-like structures, axonal beadings and dendritic cells. The Ocular Surface Disease Index (OSDI) questionnaire and Schirmer tear test were used as indicators of Dry Eye Disease (DED) and ocular surface pathology. RESULTS: Twenty-one patients (91.31%) presented alterations of the corneal subbasal plexus and corneal tissue consistent with small fiber neuropathy. Images from healthy subjects did not indicate significant nerve fiber or corneal tissue damage. Eight patients reported increased sensations of ocular dryness after COVID-19 infection and had positive DED indicators. Beaded axons were found in 82.60% of cases, mainly in patients reporting ocular irritation symptoms. Neuroma-like images were found in 65.22% patients, more frequently in those with OSDI scores >13. Dendritic cells were found in 69.56% of patients and were more frequent in younger asymptomatic patients. The presence of morphological alterations in patients up to 10 months after recovering from Sars-CoV-2 infection points to the chronic nature of the neuropathy. CONCLUSIONS: Sars-CoV-2 infection may be inducing small fiber neuropathy in the ocular surface, sharing symptomatology and morphological landmarks with DED and diabetic neuropathy.


Assuntos
COVID-19 , Síndromes do Olho Seco , Neuropatia de Pequenas Fibras , Córnea , Humanos , Microscopia Confocal , Estudos Retrospectivos , SARS-CoV-2
16.
J Neuropathol Exp Neurol ; 80(5): 446-456, 2021 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-33779723

RESUMO

The saccharide chains of heparan sulfate appear to be involved in several aspects Alzheimer disease (AD) pathogenesis. Their structural complexity is due to the expression of different isoenzymes. We studied the differential transcription of heparan sulfate chain biosynthesis in AD brains, analyzing different brain regions in patients with different extents of AD pathology. The transcriptomic study was performed by RT-PCR using samples of amygdala, anterior hippocampus, posterior hippocampus, claustrum, calcarine fissure, globus pallidus and cerebellum from patients with mild, moderate, or severe AD, as well as healthy individuals. Certain heparan sulfate epitopes were also detected by immunohistochemistry. Several genes, across all stages of heparan sulfate synthesis, showed altered transcription in different brain regions of AD patients. The numbers of alterations were greater in in moderate versus mild AD patients. In severe patients, there were fewer alterations in genes related to early stages of biosynthesis, and overexpression of genes involved in late stages. The alterations correlated with progressive brain atrophy, although alterations were more common in the cerebellum. Detection of some heparan sulfate epitopes by immunohistochemistry was consistent with previous studies. In conclusion, transcriptional alterations in the biosynthetic genes of heparan sulfate depend on the brain region and the degree of AD pathology.


Assuntos
Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Expressão Gênica/fisiologia , Heparitina Sulfato/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Encéfalo/patologia , Feminino , Humanos , Imuno-Histoquímica/métodos , Masculino
17.
Vision (Basel) ; 5(3)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34287367

RESUMO

This study aimed to investigate the use of Plasma Rich in Growth Factors (PRGF) associated with tissue ReGeneraTing Agent (RGTA) drops for the treatment of noninfectious corneal ulcers. RGTA treatment was applied (one drop every two days); however, if ulcer closure was not achieved, PRGF eye drops treatment was added (four times/day). The time taken to reach the ulcer closure, the Best Corrected Visual Acuity (BCVA), intraocular pressure (IOP), Visual Analog Scale (VAS, in terms of frequency and severity of symptoms), and Ocular Surface Disease Index (OSDI) were evaluated. Seventy-four patients (79 eyes) were included, and the mean age was 56.8 ± 17.3 years. The neurotrophic corneal ulcer was the most frequent disorder (n = 27, 34.2%), mainly for herpes virus (n = 15, 19.0%). The time of PRGF eye drops treatment associated with the RGTA matrix was 4.2 ± 2.2 (1.5-9.0) months, and the follow-up period was 44.9 ± 31.5 months. The ulcer closure was achieved in 76 eyes (96.2%). BCVA, VAS and OSDI improved from the baseline (p < 0.001), and IOP remained unchanged (p = 0.665). RGTA and PRGF in noninfectious ulcers were effective and could be a therapeutic alternative for this type of corneal disease.

18.
Cells ; 10(8)2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34440771

RESUMO

Small leucine-rich proteoglycans (SLRPs) regulate different processes and undergo significant alterations in various diseases. Colon carcinomas (CCs) are heterogeneous pathologies with important clinical and molecular differences depending on their location, which makes it interesting to analyze the alterations in SLRPs in right- and left-sided tumors (RS- and LSCCs). SLRP transcription levels were studied in 32 CCs using qPCR compared to healthy colon mucosae samples from the same patients, 20 of them from LSCCs and the remaining 12 from RSCCs. Protein expression of genes with significant differences in their transcriptions was analyzed by immunohistochemistry. The alterations observed were related to survival data. The arrangement of transcription of SLRPs was quite similar in ascending and descending colon, but RS- and LSCCs displayed different patterns of alteration, with a greater number of deregulations occurring in the latter. The analysis of protein expression also indicated changes in the location of these molecules, largely moving to the cell interior. While podocan underexpression showed a trend toward better outcomes, no differences were observed in terms of overall survival. In vitro studies using the HT29 tumor cell line suggest that deregulation of SLRPs could affect cell proliferation. SLRPs constitute new differential markers of RS- and LSCCs, showing differences dependent on the anatomical location of the tumor.


Assuntos
Adenocarcinoma/genética , Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Proteoglicanos Pequenos Ricos em Leucina/genética , Transcrição Gênica , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Idoso , Biomarcadores Tumorais/metabolismo , Diferenciação Celular , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Células HT29 , Humanos , Masculino , Invasividade Neoplásica , Prognóstico , Proteoglicanos Pequenos Ricos em Leucina/metabolismo
19.
J Neuropathol Exp Neurol ; 79(5): 474-483, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32232475

RESUMO

Previous studies have reported that heparan sulfate proteoglycans (HSPGs) promote amyloid-beta peptide and tau fibrillization in Alzheimer disease (AD) and provide resistance against proteolytic breakdown. We compared the expression levels of 17 HSPG core proteins in 18 AD cases and 6 controls. RT-PCR was used to analyze transcription levels. Immunohistochemistry was performed to localize HSPGs in the brain tissue. We detected expression of all HSPG genes investigated. SDC1, GPC3, and CD44v3 showed the lowest levels of expression, while SDC3 and GPC1 showed the highest. Remarkably, SDC4 and SRGN were overexpressed in most of the areas analyzed. Immunohistochemistry revealed the presence of both SDC4 and SRGN mostly associated with tau and amyloid-ß pathology throughout the AD brains. In conclusion, in view of the involvement of HSPGs in AD pathology, especially SDC4 and SRGN, there would seem to be a relationship between the regulation of core protein expression and the pathological features suggesting HSPGs are potential inducers of the disease.


Assuntos
Doença de Alzheimer , Proteoglicanas de Heparan Sulfato , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Encéfalo/patologia , Glipicanas/metabolismo , Proteoglicanas de Heparan Sulfato/genética , Proteoglicanas de Heparan Sulfato/metabolismo , Humanos , Imuno-Histoquímica
20.
Pathol Oncol Res ; 26(1): 167-173, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29435733

RESUMO

Hepatocellular carcinoma (HCC) is the most common type of primary malignant tumor in the liver. One of the main features of cancer survival is the generalized loss of growth control exhibited by cancer cells, and Miki is a protein related to the immunoglobulin superfamily that plays an important role in mitosis. We aim to study protein expression levels of Miki in non-tumoral liver and 20 HCCs recruited from a Pathology Department. Clinical information was also obtained. A tissue microarray was performed, and immunohistochemical techniques applied to study protein expression levels of Miki. In normal liver, Miki was weakly expressed, showing nuclear staining in the hepatocytes. Cirrhotic areas and HCCs showed a variety of staining patterns. Most HCC samples showed positive expression, with three different staining patterns being discernible: nuclear, cytoplasmic and mixed. Statistical analysis showed a significant association between grade of differentiation, Ki-67 proliferative index, survival rates and staining patterns. This study has revealed the positive expression of Miki in normal liver, cirrhotic areas and HCCs. Three different staining patterns of Miki expression with clinical relevance were noted in HCCs.


Assuntos
Carcinoma Hepatocelular/metabolismo , Proteínas de Ciclo Celular/metabolismo , Neoplasias Hepáticas/metabolismo , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/patologia , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Antígeno Ki-67/metabolismo , Fígado/metabolismo , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade
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