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1.
Environ Res ; 248: 118380, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38307182

RESUMO

Evidence suggests that myocardial interstitial fibrosis, resulting from cardiac remodeling, may possibly be influenced by mechanisms activated through the inhalation of airborne pollutants. However, limited studies have explored the relationship between lifetime exposure to carbon-based particles and cardiac fibrosis, specially using post-mortem samples. This study examined whether long-term exposure to air pollution (estimated by black carbon accumulated in the lungs) is associated with myocardial fibrosis in urban dwellers of megacity of Sao Paulo. Data collection included epidemiological and autopsy-based approaches. Information was obtained by interviewing the next of kin and through the pathologist's report. The individual index of exposure to carbon-based particles, which we designed as the fraction of black carbon (FBC), was estimated through quantification of particles on the macroscopic lung surface. Myocardium samples were collected for histopathological analysis to evaluate the fraction of cardiac fibrosis. The association between cardiac fibrosis and FBC, age, sex, smoking status and hypertension was assessed by means of multiple linear regression models. Our study demonstrated that the association of FBC with cardiac fibrosis is influenced by smoking status and hypertension. Among hypertensive individuals, the cardiac fibrosis fraction tended to increase with the increase of the FBC in both groups of smokers and non-smokers. In non-hypertensive individuals, the association between cardiac fibrosis fraction and FBC was observed primarily in smokers. Long-term exposure to tobacco smoke and environmental particles may contribute to the cardiac remodeling response in individuals with pre-existing hypertension. This highlights the importance of considering hypertension as an additional risk factor for the health effects of air pollution on the cardiovascular system. Moreover, the study endorses the role of autopsy to investigate the effects of urban environment and personal habits in determining human disease.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Hipertensão , Humanos , Poluentes Atmosféricos/análise , Brasil , Remodelação Ventricular , Pulmão , Fibrose , Carbono/análise
2.
World J Microbiol Biotechnol ; 40(1): 9, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37938391

RESUMO

The aim of the study was to track the spread of antimicrobial resistance among the different sectors of One Health through the detection of Multidrug-Efflux-System in multidrug-resistant Staphylococcus aureus isolates. Multidrug-resistant (MDR) and methicillin-resistant (MRSA) S. aureus isolates were selected: 25 of human, one of animal and eight of food origin. The efflux system genes norA, norB, norC, LmrS, tet38 and msrA were screened by PCR. The activity of the efflux systems was determined by the minimum inhibitory concentration (MIC) of tetracycline and ciprofloxacin in the presence and absence of CCCP and in the quantification of ethidium bromide efflux. Furthermore, biofilm formation was determined in the presence and absence of the CCCP. The molecular epidemiology of the isolates was traced with the aid of PFGE. The gene norC was the most prevalent, detected in all isolates and msrA was the least prevalent, detected in only two isolates from humans. There was no difference in the MICs of tetracycline and ciprofloxacin in the presence of CCCP, but 55.9% of isolates showed ethidium bromide efflux. The presence of CCCP decreased the biofilm formation. Regarding the molecular epidemiology, in three clusters was a mixture of the isolates from different origins. Therefore, S. aureus MDR with active multidrug efflux systems are circulating between One Health domains and it is necessary to consider strategies to decrease this circulation in order to prevent the dissemination of resistance mediated by MES.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Saúde Única , Infecções Estafilocócicas , Animais , Humanos , Staphylococcus aureus/genética , Carbonil Cianeto m-Clorofenil Hidrazona , Etídio , Staphylococcus aureus Resistente à Meticilina/genética , Tetraciclina/farmacologia , Ciprofloxacina/farmacologia , Antibacterianos/farmacologia
3.
Int J Cancer ; 150(5): 868-880, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34751446

RESUMO

Surgical resection with lymphadenectomy and perioperative chemotherapy is the universal mainstay for curative treatment of gastric cancer (GC) patients with locoregional disease. However, GC survival remains asymmetric in West- and East-world regions. We hypothesize that this asymmetry derives from differential clinical management. Therefore, we collected chemo-naïve GC patients from Portugal and South Korea to explore specific immunophenotypic profiles related to disease aggressiveness and clinicopathological factors potentially explaining associated overall survival (OS) differences. Clinicopathological and survival data were collected from chemo-naïve surgical cohorts from Portugal (West-Europe cohort [WE-C]; n = 170) and South Korea (East-Asia cohort [EA-C]; n = 367) and correlated with immunohistochemical expression profiles of E-cadherin and CD44v6 obtained from consecutive tissue microarrays sections. Survival analysis revealed a subset of 12.4% of WE-C patients, whose tumors concomitantly express E-cadherin_abnormal and CD44v6_very high, displaying extremely poor OS, even at TNM stages I and II. These WE-C stage-I and -II patients tumors were particularly aggressive compared to all others, invading deeper into the gastric wall (P = .032) and more often permeating the vasculature (P = .018) and nerves (P = .009). A similar immunophenotypic profile was found in 11.9% of EA-C patients, but unrelated to survival. Tumours, from stage-I and -II EA-C patients, that display both biomarkers, also permeated more lymphatic vessels (P = .003), promoting lymph node (LN) metastasis (P = .019), being diagnosed on average 8 years earlier and submitted to more extensive LN dissection than WE-C. Concomitant E-cadherin_abnormal/CD44v6_very-high expression predicts aggressiveness and poor survival of stage-I and -II GC submitted to conservative lymphadenectomy.


Assuntos
Biomarcadores Tumorais/análise , Caderinas/análise , Receptores de Hialuronatos/análise , Neoplasias Gástricas/mortalidade , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia
4.
EMBO Rep ; 21(4): e48938, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32052574

RESUMO

Intestinal stem cells (ISCs) fuel the lifelong self-renewal of the intestinal tract and are paramount for epithelial repair. In this context, the Wnt pathway component LGR5 is the most consensual ISC marker to date. Still, the effort to better understand ISC identity and regulation remains a challenge. We have generated a Mex3a knockout mouse model and show that this RNA-binding protein is crucial for the maintenance of the Lgr5+ ISC pool, as its absence disrupts epithelial turnover during postnatal development and stereotypical organoid maturation ex vivo. Transcriptomic profiling of intestinal crypts reveals that Mex3a deletion induces the peroxisome proliferator-activated receptor (PPAR) pathway, along with a decrease in Wnt signalling and loss of the Lgr5+ stem cell signature. Furthermore, we identify PPARγ activity as a molecular intermediate of MEX3A-mediated regulation. We also show that high PPARγ signalling impairs Lgr5+ ISC function, thus uncovering a new layer of post-transcriptional regulation that critically contributes to intestinal homeostasis.


Assuntos
Mucosa Intestinal , Células-Tronco , Animais , Intestinos , Camundongos , Organoides , Receptores Acoplados a Proteínas G/genética , Via de Sinalização Wnt
5.
J Cell Physiol ; 236(5): 3991-4007, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33151579

RESUMO

Musculoskeletal interfaces are naturally hypoxic. An understanding of key interactions occurring between different cell populations and their environment is critical for native tissue recapitulation. Here, an enthesis coculture model (preosteoblasts and tendon cells) was used to understand the influence of hypoxia (5% O2 ) and osteogenic medium (OM) supplementation in cells' phenotype modulation. In single cultures, preosteoblasts were found to undergo osteogenic impairment, while tendon cells underwent a maturation process through extracellular matrix (ECM) rescue. When in co-culture, hypoxia and osteoinduction promoted a temporal chondro/osteogenic pathway activation, as observed by an early deposition of cartilaginous ECM associated with HIF1A stabilization and RUNX2 activation, and later hypertrophic differentiation resulting from HIF2A translocation and SOX9 activation. Moreover, the presence of OM under hypoxia was shown to influence the extracellular ROS/HIF1A interplay. Overall, this study revealed a link between biochemical factors and cell-cell crosstalk, providing a molecular framework for hypoxic control and modulation of cells' fate toward enthesis-like phenotypes.


Assuntos
Condrócitos/metabolismo , Matriz Extracelular/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Osteogênese , Adulto , Idoso , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Biomarcadores/metabolismo , Hipóxia Celular , Condrogênese , Meios de Cultura , Regulação da Expressão Gênica , Glicosaminoglicanos/metabolismo , Humanos , Pessoa de Meia-Idade , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Estabilidade Proteica , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição SOX9/metabolismo , Transdução de Sinais , Tenócitos/metabolismo , Fatores de Tempo
6.
BMC Cancer ; 21(1): 359, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33823840

RESUMO

BACKGROUND: Colorectal cancer (CRC) remains a serious health concern worldwide. Despite advances in diagnosis and treatment, about 15 to 30% of stage II CRC patients subjected to tumor resection with curative intent, develop disease relapse. Moreover, the therapeutic strategy adopted after surgery is not consensual for these patients. This supports the imperative need to find new prognostic and predictive biomarkers for stage II CRC. METHODS: For this purpose, we used a one-hospital series of 227 stage II CRC patient samples to assess the biomarker potential of the immunohistochemical expression of MUC2 mucin and CDX2 and SOX2 transcription factors. The Kaplan-Meier method was used to generate disease-free survival curves that were compared using the log-rank test, in order to determine prognosis of cases with different expression of these proteins, different mismatch repair (MMR) status and administration or not of adjuvant chemotherapy. RESULTS: In this stage II CRC series, none of the studied biomarkers showed prognostic value for patient outcome. However low expression of MUC2, in cases with high expression of CDX2, absence of SOX2 or MMR-proficiency, conferred a significantly worst prognosis. Moreover, cases with low expression of MUC2 showed a significantly clear benefit from treatment with adjuvant chemotherapy. CONCLUSION: In conclusion, we observe that patients with stage II CRC with low expression of MUC2 in the tumor respond better when treated with adjuvant chemotherapy. This observation supports that MUC2 is involved in resistance to fluorouracil-based adjuvant chemotherapy and might be a promising future predictive biomarker in stage II CRC patients.


Assuntos
Biomarcadores Tumorais/metabolismo , Fator de Transcrição CDX2/metabolismo , Neoplasias Colorretais/genética , Mucina-2/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Adulto Jovem
7.
Mar Drugs ; 19(11)2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34822494

RESUMO

Bioactive lipidic compounds of microalgae, such as polyunsaturated fatty acids (PUFA) and carotenoids, can avoid or treat oxidation-associated conditions and diseases like inflammation or cancer. This study aimed to assess the bioactive potential of lipidic extracts obtained from Gloeothece sp.-using Generally Recognized as Safe (GRAS) solvents like ethanol, acetone, hexane:isopropanol (3:2) (HI) and ethyl lactate. The bioactive potential of extracts was assessed in terms of antioxidant (ABTS•+, DPPH•, •NO and O2•assays), anti-inflammatory (HRBC membrane stabilization and Cox-2 screening assay), and antitumor capacity (death by TUNEL, and anti-proliferative by BrdU incorporation assay in AGS cancer cells); while its composition was characterized in terms of carotenoids and fatty acids, by HPLC-DAD and GC-FID methods, respectively. Results revealed a chemopreventive potential of the HI extract owing to its ability to: (I) scavenge -NO• radical (IC50, 1258 ± 0.353 µg·mL-1); (II) inhibit 50% of COX-2 expression at 130.2 ± 7.4 µg·mL-1; (III) protect 61.6 ± 9.2% of lysosomes from heat damage, and (IV) induce AGS cell death by 4.2-fold and avoid its proliferation up to 40% in a concentration of 23.2 ± 1.9 µg·mL-1. Hence, Gloeothece sp. extracts, namely HI, were revealed to have the potential to be used for nutraceutical purposes.


Assuntos
Cianobactérias , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Organismos Aquáticos , Compostos de Bifenilo , Linhagem Celular Tumoral , Humanos , Concentração Inibidora 50 , Picratos
8.
Lab Invest ; 100(1): 120-134, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31641225

RESUMO

Flourescence-based multiplex immunohistochemistry (mIHC) combined with multispectral imaging and digital image analysis (DIA) is a quantitative high-resolution method for determination of protein expression in tissue. We applied this method for five biomarkers (CDX2, SOX2, SOX9, E-cadherin, and ß-catenin) using tissue microarrays of a Norwegian unselected series of primary colorectal cancer. The data were compared with previously obtained chromogenic IHC data of the same tissue cores, visually assessed by the Allred method. We found comparable results between the methods, although confirmed that DIA offered improved resolution to differentiate cases with high and low protein expression. However, we experienced inherent challenges with digital image analysis of membrane staining, which was better assessed visually. DIA and mIHC enabled quantitative analysis of biomarker coexpression on the same tissue section at the single-cell level, revealing a strong negative correlation between the differentiation markers CDX2 and SOX2. Both methods confirmed known prognostic associations for CDX2, but DIA improved data visualization and detection of clinicopathological and biological associations. In summary, mIHC combined with DIA is an efficient and reliable method to evaluate protein expression in tissue, here shown to recapitulate and improve detection of known clinicopathological and survival associations for the emerging biomarker CDX2, and is therefore a candidate approach to standardize CDX2 detection in pathology laboratories.


Assuntos
Biomarcadores Tumorais/análise , Imunofluorescência , Interpretação de Imagem Assistida por Computador , Biomarcadores Tumorais/metabolismo , Fator de Transcrição CDX2/metabolismo , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/metabolismo , Humanos , Fatores de Transcrição SOXB1/metabolismo , Análise Serial de Tecidos
9.
Gastric Cancer ; 23(5): 811-823, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32215766

RESUMO

BACKGROUND: Gastric cancer is the fifth most common cancer and the third cause of global cancer mortality. CDX2 is an intestinal differentiation marker with prognostic value in gastric cancer and transcriptionally regulates the expression of glycoprotein A33 (GPA33) and liver intestine cadherin (LI-cadherin). METHODS: This study evaluated the clinical significance of the combined expression of CDX2 and its targets GPA33 and LI-cadherin in gastric cancer by fluorescence-based multiplex immunohistochemistry together with digital image analysis and chromogenic immunohistochemistry in 329 gastric cancer samples arranged in tissue microarrays. Additionally, publicly available RNA-seq expression data from 354 gastric cancer samples from the TCGA database were used to validate the immunohistochemistry results. RESULTS: Expression of the three markers (CDX2, GPA33, and LI-cadherin) was strongly correlated, defining an intestinal differentiation panel. Low or negative protein expression of the intestinal differentiation panel identified patients with particularly poor overall survival, irrespective of the methodology used, and was validated in the independent series at the RNA-seq level. CONCLUSIONS: Expression of the intestinal differentiation panel (CDX2, GPA33, and LI-cadherin) defines a set of biomarkers with a strong biological rationale and favourable impact for prognostication of gastric cancer patients.


Assuntos
Antígenos de Diferenciação/metabolismo , Biomarcadores Tumorais/metabolismo , Fator de Transcrição CDX2/metabolismo , Caderinas/metabolismo , Intestinos/citologia , Glicoproteínas de Membrana/metabolismo , Neoplasias Gástricas/patologia , Idoso , Diferenciação Celular , Feminino , Seguimentos , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/cirurgia , Taxa de Sobrevida
10.
Chem Biodivers ; 17(6): e2000142, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32294320

RESUMO

Leishmaniasis is a neglected disease, caused by a parasite of Leishmania genus and widespread in the tropical and subtropical areas of the world. Currents drugs are limited due to their toxicity and parasite resistance. Therefore, the discovery of new treatment, more effective and less toxic, is urgent. In this study, we report the synthesis of six gem-dihydroperoxides (2a-2f), with yields ranging from 10 % to 90 %, utilizing a new methodology. The dihydroperoxides were converted into ten tetroxanes (3a-3j), among which six (3b, 3c, 3d, 3g, 3h and 3j) showed activity against intracellular amastigotes of Leishmania amazonensis. The cytotoxicity of all compounds was also evaluated against canine macrophages (DH82), human hepatoma (HepG2) and monkey renal cells (BGM). Most compounds were more active and less toxic than potassium antimonyl tartrate trihydrate, used as positive control. Amongst all tetroxanes, 3b (IC50 =0.64 µm) was the most active, being more selective than positive control in relation to DH82, HepG2 and BGM cells. In summary, the results revealed a hit compound for the development of new drugs to treat leishmaniasis.


Assuntos
Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Tetraoxanos/química , Animais , Antiprotozoários/síntese química , Antiprotozoários/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cães , Haplorrinos , Humanos , Macrófagos/citologia , Macrófagos/metabolismo , Tetraoxanos/síntese química , Tetraoxanos/farmacologia
11.
J Infect Dis ; 219(3): 365-374, 2019 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-30053014

RESUMO

Background: Zika virus (ZIKV) infection has been associated with prolonged viral excretion in human semen and causes testicular atrophy and infertility in 10-week-old immunodeficient mice. Methods: Male IFNAR-/- mice, knockout for type I interferon receptor, were immunized with GLS-5700, a deoxyribonucleic acid-based vaccine, before a subcutaneous ZIKV challenge with 6 × 105 plaque-forming units at 13 weeks of age. On day 28 postinfection, testes and epididymides were collected in some mice for histological and functional analyses, whereas others were mated with naive female wild-type C57BL/6J. Results: Although all mice challenged with ZIKV developed viremia, most of them were asymptomatic, showed no weight loss, and survived infection. On day 28 postinfection, none of the unvaccinated, infected mice (9 of 9) exhibited abnormal spermatozoa counts or motility. However, 33% (3 of 9) and 36% (4 of 11) of mated males from this group were infertile, from 2 independent studies. Contrarily, males from the noninfected and the vaccinated, infected groups were all fertile. On days 75 and 207 postinfection, partial recovery of fertility was observed in 66% (2 of 3) of the previously infertile males. Conclusions: This study reports the effects of ZIKV infection on male fertility in a sublethal, immunodeficient mouse model and the efficacy of GLS-5700 vaccination in preventing male infertility.


Assuntos
DNA/farmacologia , Infertilidade Masculina/tratamento farmacológico , Infertilidade Masculina/etiologia , Infertilidade Masculina/prevenção & controle , Infecção por Zika virus/complicações , Animais , Atrofia/etiologia , Modelos Animais de Doenças , Epididimo/patologia , Feminino , Imunização , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos SCID , Receptor de Interferon alfa e beta/genética , Sêmen , Comportamento Sexual Animal , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides , Testículo/patologia , Vacinação
12.
Cell Commun Signal ; 17(1): 155, 2019 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-31767037

RESUMO

BACKGROUND: E-cadherin has been awarded a key role in the aetiology of both sporadic and hereditary forms of gastric cancer. In this study, we aimed to identify molecular interactors that influence the expression and function of E-cadherin associated to cancer. METHODS: A data mining approach was used to predict stomach-specific candidate genes, uncovering S100P as a key candidate. The role of S100P was evaluated through in vitro functional assays and its expression was studied in a gastric cancer tissue microarray (TMA). RESULTS: S100P was found to contribute to a cancer pathway dependent on the context of E-cadherin function. In particular, we demonstrated that S100P acts as an E-cadherin positive regulator in a wild-type E-cadherin context, and its inhibition results in decreased E-cadherin expression and function. In contrast, S100P is likely to be a pro-survival factor in gastric cancer cells with loss of functional E-cadherin, contributing to an oncogenic molecular program. Moreover, expression analysis in a gastric cancer TMA revealed that S100P expression impacts negatively among patients bearing Ecad- tumours, despite not being significantly associated with overall survival on its own. CONCLUSIONS: We propose that S100P has a dual role in gastric cancer, acting as an oncogenic factor in the context of E-cadherin loss and as a tumour suppressor in a functional E-cadherin setting. The discovery of antagonist effects of S100P in different E-cadherin contexts will aid in the stratification of gastric cancer patients who may benefit from S100P-targeted therapies.


Assuntos
Caderinas/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Gástricas/metabolismo , Caderinas/genética , Proteínas de Ligação ao Cálcio/genética , Humanos , Proteínas de Neoplasias/genética , Transdução de Sinais/genética , Neoplasias Gástricas/patologia , Células Tumorais Cultivadas
13.
Nucleic Acids Res ; 45(13): e123, 2017 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-28472465

RESUMO

Tetracycline-based inducible systems provide powerful methods for functional studies where gene expression can be controlled. However, the lack of tight control of the inducible system, leading to leakiness and adverse effects caused by undesirable tetracycline dosage requirements, has proven to be a limitation. Here, we report that the combined use of genome editing tools and last generation Tet-On systems can resolve these issues. Our principle is based on precise integration of inducible transcriptional elements (coined PrIITE) targeted to: (i) exons of an endogenous gene of interest (GOI) and (ii) a safe harbor locus. Using PrIITE cells harboring a GFP reporter or CDX2 transcription factor, we demonstrate discrete inducibility of gene expression with complete abrogation of leakiness. CDX2 PrIITE cells generated by this approach uncovered novel CDX2 downstream effector genes. Our results provide a strategy for characterization of dose-dependent effector functions of essential genes that require absence of endogenous gene expression.


Assuntos
Edição de Genes/métodos , Regulação da Expressão Gênica , Fator de Transcrição CDX2/antagonistas & inibidores , Fator de Transcrição CDX2/genética , Linhagem Celular , Éxons , Perfilação da Expressão Gênica , Técnicas de Inativação de Genes , Marcação de Genes , Genes Reporter , Proteínas de Fluorescência Verde/genética , Humanos , Tetraciclina
14.
Adv Exp Med Biol ; 1144: 71-90, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30632116

RESUMO

The complex heterogeneous cellular environment found in tendon-to-bone interface makes this structure a challenge for interface tissue engineering. Orthopedic surgeons still face some problems associated with the formation of fibrotic tissue or re-tear occurring after surgical re-attachment of tendons to the bony insertion or the application of grafts. Unfortunately, an understanding of the cellular component of enthesis lags far behind of other well-known musculoskeletal interfaces, which blocks the development of new treatment options for the healing and regeneration of this multifaceted junction. In this chapter, the main characteristics of tendon and bone cell populations are introduced, followed by a brief description of the interfacial cellular niche, highlighting molecular mechanisms governing tendon-to-bone attachment and mineralization. Finally, we describe and critically assess some challenges faced concerning the use of cell-based strategies in tendon-to-bone healing and regeneration.


Assuntos
Osso e Ossos/citologia , Tendões/citologia , Engenharia Tecidual , Humanos , Cicatrização
15.
Int J Mol Sci ; 20(12)2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31248196

RESUMO

Tendon tissues have limited healing capacity. The incidence of tendon injuries and the unsatisfactory functional outcomes of tendon repair are driving the search for alternative therapeutic approaches envisioning tendon regeneration. Cellular therapies aim at delivering adequate, regeneration-competent cell types to the injured tendon and toward ultimately promoting its reconstruction and recovery of functionality. Mesenchymal stem cells (MSCs) either obtained from tendons or from non-tendon sources, like bone marrow (BM-MSCs) or adipose tissue (ASCs), have been receiving increasing attention over the years toward enhancing tendon healing. Evidences from in vitro and in vivo studies suggest MSCs can contribute to accelerate and improve the quality of tendon healing. Nonetheless, the exact mechanisms underlying these repair events are yet to be fully elucidated. This review provides an overview of the main challenges in the field of cell-based regenerative therapies, discussing the role of MSCs in boosting tendon regeneration, particularly through their capacity to enhance the tenogenic properties of tendon resident cells.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Regeneração , Traumatismos dos Tendões/terapia , Tendões/citologia , Tendões/metabolismo , Animais , Diferenciação Celular , Terapia Baseada em Transplante de Células e Tecidos , Humanos , Medicina Regenerativa , Traumatismos dos Tendões/etiologia , Engenharia Tecidual
16.
J Cell Physiol ; 233(7): 5383-5395, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29215729

RESUMO

Tendon injuries constitute an unmet clinical challenge owing to the limited intrinsic regenerative ability of this tissue. Cell-based therapies aim at improving tendon healing through the delicate orchestration of tissue rebuilding and regain of function. Hence, human adipose-derived stem cells (hASCs) have been proposed as a promising cell source for boosting tendon regeneration. In this work, we investigated the influence of hASCs on native human tendon-derived cells (hTDCs) through the establishment of a direct contact co-culture system. Results demonstrated that direct interactions between these cell types resulted in controlled proliferation and spontaneous cell elongation. ECM-related genes, particularly COL1A1 and TNC, and genes involved in ECM remodeling, such as MMP1, MMP2, MMP3, and TIMP1, were expressed in co-culture in a temporally regulated manner. In addition, deposition of collagen type I was accelerated in co-culture systems and favored over the production of collagen type III, resulting in an enhanced COL1/COL3 ratio as soon as 7 days. In conclusion, hASCs seem to be good candidates in modulating the behavior of native tendon cells, particularly through a balanced process of ECM synthesis and degradation.


Assuntos
Diferenciação Celular/genética , Matriz Extracelular/genética , Células-Tronco/citologia , Tendões/crescimento & desenvolvimento , Adipócitos/citologia , Adipócitos/metabolismo , Tecido Adiposo/citologia , Proliferação de Células/genética , Sobrevivência Celular/genética , Colágeno Tipo I/genética , Cadeia alfa 1 do Colágeno Tipo I , Colágeno Tipo III/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Metaloproteinase 1 da Matriz/genética , Tenascina/genética , Engenharia Tecidual , Inibidor Tecidual de Metaloproteinase-1/genética
17.
J Cell Physiol ; 233(10): 6395-6405, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29741815

RESUMO

Tendons are mechanosensitive tissues that connect and transmit the forces generated by muscles to bones by allowing the conversion of mechanical input into biochemical signals. These physical forces perform the fundamental work of preserving tendon homeostasis assuring body movements. However, overloading causes tissue injuries, which leads us to the field of tendon regeneration. Recently published reviews have broadly shown the use of biomaterials and different strategies to attain tendon regeneration. In this review, our focus is the use of magnetic fields as an alternative therapy, which has demonstrated clinical relevance in tendon medicine because of their ability to modulate cell fate. Yet the underlying cellular and molecular mechanisms still need to be elucidated. While providing a brief outlook about specific signalling pathways and intracellular messengers as framework in play by tendon cells, application of magnetic fields as a subcategory of physical forces is explored, opening up a compelling avenue to enhance tendon regeneration. We outline here useful insights on the effects of magnetic fields both at in vitro and in vivo levels, particularly on the expression of tendon genes and inflammatory cytokines, ultimately involved in tendon regeneration. Subsequently, the potential of using magnetically responsive biomaterials in tendon tissue engineering is highlighted and future directions in magnetotherapy are discussed.


Assuntos
Campos Magnéticos , Traumatismos dos Tendões/terapia , Tendões/efeitos da radiação , Engenharia Tecidual , Animais , Diferenciação Celular/efeitos da radiação , Homeostase , Humanos , Músculos/efeitos da radiação , Regeneração/efeitos da radiação , Traumatismos dos Tendões/fisiopatologia , Tendões/crescimento & desenvolvimento , Cicatrização/efeitos da radiação
18.
J Cell Biochem ; 119(4): 3653-3662, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29231990

RESUMO

Poor clinical outcomes of tendon repair, together with limited regenerative capacity of the tissue, have triggered the search for alternative regenerative medicine strategies. Human adipose-derived stem cells (hASCs) are being investigated as a promising cell source in contributing for tendon repopulation and reconstruction. However, the mechanisms involved in a potential beneficial effect in tendon regeneration are still to be uncovered. To gain further insights on the bi-directional crosstalk occurring between stem cells and the native tendon niche, it was used an indirect (trans-well) system for co-culturing human tendon explants and hASCs. The maintenance of tissue architecture was studied up to 14 days by histological techniques. The secretion of MMPs was evaluated at day 3. The behavior of hASCs was assessed regarding cell elongation and extracellular matrix (ECM) production. The paracrine communication enhanced collagenolytic activity of MMPs in co-cultures at day 3, in comparison to hASCs alone or tendon explants alone, suggesting that ECM remodeling is triggered early in culture. Moreover, hASCs were spontaneously more elongated in co-cultures and the deposition of collagen type III and tenascin-C by hASCs in co-culture was observed at a lower extent after 7 days, in comparison to hASCs alone, being lately recovered at day 14. Overall, explant co-cultures established herein may constitute a tool for replicating the first steps in tendon healing and help uncovering the bi-directional communication occurring between hASCs and the native tendon niche.


Assuntos
Adipócitos/citologia , Células-Tronco/citologia , Tendões/citologia , Engenharia Tecidual/métodos , Adipócitos/metabolismo , Tecido Adiposo/citologia , Diferenciação Celular/fisiologia , Técnicas de Cocultura , Colágeno Tipo III/metabolismo , Matriz Extracelular/metabolismo , Humanos , Células-Tronco/metabolismo , Tendões/metabolismo , Transplante de Tecidos
19.
RNA Biol ; 15(6): 829-831, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29671387

RESUMO

The genetic alphabet consists of the four letters: C, A, G, and T in DNA and C,A,G, and U in RNA. Triplets of these four letters jointly encode 20 different amino acids out of which proteins of all organisms are built. This system is universal and is found in all kingdoms of life. However, bases in DNA and RNA can be chemically modified. In DNA, around 10 different modifications are known, and those have been studied intensively over the past 20 years. Scientific studies on DNA modifications and proteins that recognize them gave rise to the large field of epigenetic and epigenomic research. The outcome of this intense research field is the discovery that development, ageing, and stem-cell dependent regeneration but also several diseases including cancer are largely controlled by the epigenetic state of cells. Consequently, this research has already led to the first FDA approved drugs that exploit the gained knowledge to combat disease. In recent years, the ~150 modifications found in RNA have come to the focus of intense research. Here we provide a perspective on necessary and expected developments in the fast expanding area of RNA modifications, termed epitranscriptomics.


Assuntos
DNA de Neoplasias , Epigênese Genética , Epigenômica/normas , Perfilação da Expressão Gênica/normas , Regulação Neoplásica da Expressão Gênica , Neoplasias , RNA Neoplásico , Transcriptoma , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Europa (Continente) , Perfilação da Expressão Gênica/métodos , Humanos , Neoplasias/genética , Neoplasias/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo
20.
Nanomedicine ; 14(7): 2375-2385, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-28614734

RESUMO

Photocrosslinkable magnetic hydrogels are attracting great interest for tissue engineering strategies due to their versatility and multifunctionality, including their remote controllability ex vivo, thus enabling engineering complex tissue interfaces. This study reports the development of a photocrosslinkable magnetic responsive hydrogel made of methacrylated chondroitin sulfate (MA-CS) enriched with platelet lysate (PL) with tunable features, envisioning their application in tendon-to-bone interface. MA-CS coated iron-based magnetic nanoparticles were incorporated to provide magnetic responsiveness to the hydrogel. Osteogenically differentiated adipose-derived stem cells and/or tendon-derived cells were encapsulated within the hydrogel, proliferating and expressing bone- and tendon-related markers. External magnetic field (EMF) application modulated the swelling, degradation and release of PL-derived growth factors, and impacted both cell morphology and the expression and synthesis of tendon- and bone-like matrix with a more evident effect in co-cultures. Overall, the developed magnetic responsive hydrogel represents a potential cell carrier system for interfacial tissue engineering with EMF-controlled properties.


Assuntos
Tecido Adiposo/citologia , Hidrogéis/química , Magnetismo , Células-Tronco/citologia , Tendões/citologia , Engenharia Tecidual , Diferenciação Celular , Células Cultivadas , Humanos , Osteogênese
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