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1.
iScience ; 27(7): 110346, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39055920

RESUMO

Over 80% of the patients with pancreatic ductal adenocarcinoma (PDAC) have cachexia/wasting syndrome. Cachexia is associated with reduced survival, decreased quality of life, and higher metastasis rates. Here, we demonstrate that fat loss is the earliest feature of PDAC-exosome-induced cachexia. MicroRNA sequencing of exosomal components from normal and cancer-derived exosomes revealed enrichment of miR-16-5p, miR-21-5p, miR-29a-3p, and miR-125b-5p in serum exosomes of mice harboring PDAC and patients with PDAC. Further, miR-16-5p and miR-29a-3p inhibited adipogenesis through decreasing Erlin2 and Cmpk1 expression which downregulates C/EBPß and PPARγ. Synergistically, miR-29a-3p promotes lipolysis through increasing ATGL expression by suppressing MCT1 expression. Furthermore, PDAC-exosomes deprived of miR-16-5p and miR-29a-3p fail to induce fat loss. Hence, miR-16-5p and miR-29a-3p exosomal miRs are essential for PDAC-induced fat loss. Thus, we unravel that PDAC induces adipose atrophy via exosomal miRs. This knowledge may provide new diagnostic and therapeutic strategies for PDAC-induced cachexia.

2.
Res Sq ; 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37886583

RESUMO

We developed a computational framework that integrates Genome-Wide Association Studies (GWAS) and post-GWAS analyses, designed to facilitate drug repurposing for COVID-19 treatment. The comprehensive approach combines transcriptomic-wide associations, polygenic priority scoring, 3D genomics, viral-host protein-protein interactions, and small-molecule docking. Through GWAS, we identified nine druggable host genes associated with COVID-19 severity and SARS-CoV-2 infection, all of which show differential expression in COVID-19 patients. These genes include IFNAR1, IFNAR2, TYK2, IL10RB, CXCR6, CCR9, and OAS1. We performed an extensive molecular docking analysis of these targets using 553 small molecules derived from five therapeutically enriched categories, namely antibacterials, antivirals, antineoplastics, immunosuppressants, and anti-inflammatories. This analysis, which comprised over 20,000 individual docking analyses, enabled the identification of several promising drug candidates. All results are available via the DockCoV2 database (https://dockcov2.org/drugs/). The computational framework ultimately identified nine potential drug candidates: Peginterferon alfa-2b, Interferon alfa-2b, Interferon beta-1b, Ruxolitinib, Dactinomycin, Rolitetracycline, Irinotecan, Vinblastine, and Oritavancin. While its current focus is on COVID-19, our proposed computational framework can be applied more broadly to assist in drug repurposing efforts for a variety of diseases. Overall, this study underscores the potential of human genetic studies and the utility of a computational framework for drug repurposing in the context of COVID-19 treatment, providing a valuable resource for researchers in this field.

3.
Exp Biol Med (Maywood) ; 248(20): 1695-1707, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37646261

RESUMO

Resistin and suppressors of cytokine signaling (SOCSs) have been reported to regulate prostate cancer (PCa) cell proliferation and survival, respectively. Whether any of the SOCS molecules mediate the mitogenic effect of resistin on PCa cells is unknown. Using PC-3 human PCa cells, we found that resistin upregulates the expression of SOCS3 and SOCS5 mRNA, but not SOCS7 mRNA, in a dose- and time-dependent manner. The resistin-induced increases in SOCS3 and SOCS5 expression and cell proliferation were prevented by pretreatment with specific inhibitors of the TLR4, ERK, p38 MAPK, JNK, PI3K, and JAK2 proteins. However, pretreatment with a TLR2 inhibitor had no effect on resistin-mediated SOCS3 and SOCS5 expression. In addition, the effects of resistin on SOCS3, SOCS5, and SOCS7 mRNA levels were cell type-specific. Overexpression of either SOCS3 or SOCS5 enhanced further resistin-stimulated growth of PC-3 cells, whereas silencing SOCS3 or SOCS5 antagonized resistin-increased cell growth. Further PCa tissue analysis demonstrated higher levels of RETN, TLR4, SOCS3, and SOCS5 mRNAs in cancer tissues than benign prostate hyperplasia and indicated positive correlations among RETN, TLR4, and SOCS5. These data suggest that SOCS5, TLR4, and, to a lesser extent, SOCS3 can mediate the mitogenic effect of resistin on PC-3 PCa cells.


Assuntos
Próstata , Neoplasias da Próstata , Humanos , Masculino , Células PC-3 , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Resistina/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas/genética , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Proteínas Supressoras da Sinalização de Citocina/genética , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Receptor 4 Toll-Like/metabolismo
5.
J Chem Phys ; 159(2)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37428066

RESUMO

Directional wicking and spreading of liquids can be achieved by regular micro-patterns of specifically designed topographic features that break the reflection symmetry of the underlying pattern. The present study aims to understand the formation and stability of wetting films during the evaporation of volatile liquid drops on surfaces with a micro-pattern of triangular posts arranged in a rectangular lattice. Depending on the density and aspect ratio of the posts, we observe either spherical-cap shaped drops with a mobile three-phase contact line or the formation of circular or angular drops with a pinned three-phase contact line. Drops of the latter class eventually evolve into a liquid film extending to the initial footprint of the drop and a shrinking cap-shaped drop sitting on the film. The drop evolution is controlled by the density and aspect ratio of the posts, while no influence of the orientation of the triangular posts on the contact line mobility becomes evident. Our experiments corroborate previous results of systematic numerical energy minimization, predicting that conditions for a spontaneous retraction of a wicking liquid film depend weakly on the orientation of the film edge relative to the micro-pattern.

6.
Mol Oncol ; 17(8): 1628-1647, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37171030

RESUMO

Cancer-associated fibroblasts (CAFs), a major component of the tumor microenvironment (TME) in pancreatic ductal adenocarcinoma (PDAC), play an important role in tumorigenesis, metastasis, and chemoresistance. Tumor-derived small extracellular vesicles (sEVs), which mediate cell-to-cell communication between cancer cells and fibroblasts, are also critical for cancer progression and metastasis. However, it remains unclear how PDAC cell-derived sEVs activate fibroblasts, which contributes to tumor progression. Here, we report that ezrin (EZR) expression in PDAC cell-derived sEVs (sEV-EZR) can activate fibroblasts, resulting in increased migration ability and high expression of α-SMA, PDGFRB, and high production of extracellular matrix in fibroblasts. Reciprocally, sEV-EZR-activated fibroblasts enhanced PDAC cell proliferation, invasion, and metastasis to the liver in animal models. Conversely, fibroblasts treated with PDAC cell-derived sEVs with EZR knockdown resulted in the reduced metastatic ability of PDAC. Mechanistically, we demonstrated that PDAC cell-derived sEV-EZR increases the STAT3 and YAP-1 signaling pathways to induce fibroblast activation, and the activated fibroblasts promote PDAC cell proliferation, invasion, and liver metastasis. Inhibition of the STAT3 and YAP-1 signaling pathways by gene knockdown can abrogate sEV-EZR-induced effects. These findings suggest that targeting the interaction between PDAC cell-derived sEV-EZR and fibroblasts is a potential therapeutic strategy for PDAC.


Assuntos
Adenocarcinoma , Fibroblastos Associados a Câncer , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animais , Neoplasias Pancreáticas/patologia , Transdução de Sinais , Carcinoma Ductal Pancreático/patologia , Proliferação de Células/genética , Adenocarcinoma/patologia , Fibroblastos Associados a Câncer/metabolismo , Linhagem Celular Tumoral , Microambiente Tumoral , Neoplasias Pancreáticas
7.
PLoS One ; 17(11): e0277561, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36355857

RESUMO

Acute myocardial infarction (AMI) results in weakening of the heart muscle and an increased risk for chronic heart failure. Therapeutic stem cells have been shown to reduce inflammatory signaling and scar tissue expansion, despite most of these studies being limited by poor retention of cells. Gelatin methacrylate (GelMA) coatings have been shown to increase the retention of these therapeutic cells near the infarct. In this work, we evaluate two different potential binding partners for GelMA-coated bone marrow cells (BMCs) and myocardial tissue: the extracellular matrix (ECM) and interstitial non-cardiomyocytes. While cells containing ß1 integrins mediate cell-ECM adhesion in vivo, these cells do not promote binding to our collagen-degraded, GelMA coating. Specifically, microscopic imagining shows that even with high integrin expression, GelMA-coated BMCs do not bind to cells within the myocardium. Alternatively, BMC incubation with decellularized heart tissue results in higher adhesion of coated cells versus uncoated cells supporting our GelMA-ECM binding mode. To further evaluate the ECM binding mode, cells were incubated on slides modified with one of three different major heart ECM components: collagen, laminin, or fibronectin. While all three components promoted higher adhesion than unmodified glass, collagen-coated slides resulted in a significantly higher adhesion of GelMA-coated BMCs over laminin and fibronectin. Incubation with unmodified BMCs confirmed that without a GelMA coating minimal adhesion of BMCs occurred. We conclude that GelMA cellular coatings significantly increase the binding of cells to collagen within the ECM. Our results provide progress towards a biocompatible and easily translatable method to enhance the retention of transplanted cells in human studies.


Assuntos
Gelatina , Infarto do Miocárdio , Humanos , Gelatina/farmacologia , Gelatina/metabolismo , Adesão Celular , Fibronectinas/metabolismo , Laminina/metabolismo , Miocárdio , Matriz Extracelular/metabolismo , Colágeno/metabolismo , Metacrilatos , Infarto do Miocárdio/terapia , Infarto do Miocárdio/metabolismo
9.
Nucleic Acids Res ; 50(W1): W616-W622, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35536289

RESUMO

With the proliferation of genomic sequence data for biomedical research, the exploration of human genetic information by domain experts requires a comprehensive interrogation of large numbers of scientific publications in PubMed. However, a query in PubMed essentially provides search results sorted only by the date of publication. A search engine for retrieving and interpreting complex relations between biomedical concepts in scientific publications remains lacking. Here, we present pubmedKB, a web server designed to extract and visualize semantic relationships between four biomedical entity types: variants, genes, diseases, and chemicals. pubmedKB uses state-of-the-art natural language processing techniques to extract semantic relations from the large number of PubMed abstracts. Currently, over 2 million semantic relations between biomedical entity pairs are extracted from over 33 million PubMed abstracts in pubmedKB. pubmedKB has a user-friendly interface with an interactive semantic graph, enabling the user to easily query entities and explore entity relations. Supporting sentences with the highlighted snippets allow to easily navigate the publications. Combined with a new explorative approach to literature mining and an interactive interface for researchers, pubmedKB thus enables rapid, intelligent searching of the large biomedical literature to provide useful knowledge and insights. pubmedKB is available at https://www.pubmedkb.cc/.


Assuntos
Computadores , Ferramenta de Busca , Humanos , PubMed , Semântica , Mineração de Dados/métodos
10.
Taiwan J Obstet Gynecol ; 61(2): 306-311, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35361392

RESUMO

OBJECTIVE: The clinical presentation of non-gastric GISTs might mimic adnexal cancer, and non-gastric GIST might be managed and treated by gynecologists. Knowledge of the clinical outcomes of women with non-gastric gastrointestinal stromal tumors (GISTs) is important. Our aim is to elucidate the factors affecting the clinical outcomes of women with non-gastric GISTs. MATERIALS AND METHODS: Between January 2000 and October 2019, all consecutive women with non-gastric GISTs who underwent surgery in a tertiary referral center were reviewed. RESULTS: Twenty-six women were reviewed. Eight (31%) women experienced recurrence. The probabilities of recurrence-free survival (RFS) at 60 and 120 months were 65.2% and 55.9%, respectively. The probabilities of overall survival (OS) at 60 and 120 months were 71.1% and 63.9%, respectively. Cancer stage was the only independent predictor of RFS (hazard ratio = 6.00, p = 0.007) and OS (hazard ratio = 3.88, p = 0.04). However, excluding cancer stage, metastasis (hazard ratio = 8.74) was the only independent predictor of RFS, and tumor size (hazard ratio = 1.20) and metastasis (hazard ratio = 6.03) were independent predictors of OS. Tumor size ≥13.9 cm was the optimum cut-off value to predict death and had an area under the receiver operating characteristic curve of 0.75 (95% confidence interval = 0.53 to 0.98). Among the above 5 women with non-gastric GISTs admitted to the Gynecology Department, optimal debulking surgery was performed in two women, and small bowel resection was performed in three women; and all five women remained alive without disease. CONCLUSION: Non-gastric GISTs may mimic gynecologic tumors. Metastasis was an independent predictor of PFS. In addition, metastasis and large tumor size (especially ≥13.9 cm) were independent predictors of OS in women with non-gastric GISTs.


Assuntos
Tumores do Estroma Gastrointestinal , Feminino , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/patologia , Tumores do Estroma Gastrointestinal/cirurgia , Humanos , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Retrospectivos
11.
Healthcare (Basel) ; 10(3)2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35327063

RESUMO

PURPOSE: This systematic review and meta-analysis was conducted to explore the effect of physical training on frailty status and physical performance in the community dwelling elderly. METHODS: We set keywords and used the Boolean operator to search the CEPS, CINAHL, Cochrane Library, PubMed, MEDLINE, and EMBASE databases from inception to 10 August 2021. The search was limited to randomized controlled trials (RCTs) conducted within a five-year period. The Cochrane Collaboration bias assessment tool was used to assess article quality, and RevMan 5.4.1. software (Cochrane Training site based in London, UK) was used to conduct the meta-analysis. RESULTS: Physical training was found to improve frailty status, physical performance, lower limb strength and balance. The best dose-response for physical training was 60 min per time, 2-3 times per week, for 3 months. CONCLUSION: Designing an appropriate physical training program can decrease the frailty score and increase physical performance in frail elderly in the community.

12.
Front Med (Lausanne) ; 9: 845411, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35345765

RESUMO

Background: Orbital apex syndrome (OAS) is a rare ocular complication following by infection, inflammation, trauma, neoplasms, and vascularity. The epidemiological features of OAS remained limited, so this study aimed to present ophthalmic clinical features, determine the causes to evaluate the visual prognosis of orbital apex syndrome (OAS) patients in Taiwan. Methods: This was a retrospective study by reviewing the electronic medical records from National Cheng Kung University Hospital in Taiwan during 2017-2019. We included patients diagnosed with OAS to review their ocular symptoms and signs, visual acuity, ocular images, etiologies, treatment and visual prognosis. Results: Twenty cases (mean age: 65.55 ± 13.06; male: 75%) with the diagnosis of OAS were included in this study. All patients presented as unilateral involvement, but the initial ocular presentations and etiologies varied. For example, blurred vision was reported in 80% of these patients, and tumor-related compression (55%) and infection (15%) were the most frequent causes for the OAS. After the follow-up, we found 35% of patients' visions declined or worsened to the blindness, 15% of patients' visions remained stable, 20% of patients' visions had mild improvement, and 35% of patients' visions were not measured because of debilitating clinical condition. We identified three OAS patients with mortality (15%), and all of them were attributed to the underlying malignancies. Conclusion: The clinical magnifications and etiologies of OAS are heterogeneous in Taiwan. Our findings indicated the tumor-related compression is the most frequent causes of OAS in Taiwan, and it is also related to poor clinical outcomes.

13.
J Cell Commun Signal ; 16(4): 567-578, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35247157

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is a malignancy with a worldwide distribution. Although intensive studies have been made, the underlying oncogenic mechanism of HNSCC requires further investigation. In this study, we examined the oncogenic role of activated Cdc42-associated kinase 1 (ACK1), an oncogenic tyrosine kinase, in regulating the proliferation of HNSCC cells and its underlying molecular mechanism. Results from immunohistochemical studies revealed that ACK1 was highly expressed in HNSCC tumors, with 77% (77/100) of tumors showing a high ACK1 immunoreactivity compared to 40% (8/20) of normal mucosa. Knockdown of ACK1 expression in HNSCC cells resulted in elevated p27 expression, reduced cell proliferation, and G1-phase cell cycle arrest. Rescue of ACK1 expression in the ACK1-knockdown cells suppressed p27 expression and restored cell proliferation. Compared to ACK1-knockdown cells, ACK1-rescued cells exhibited a restored p27 expression after MG132 treatment and showed an elevated level of ubiquitinated p27. Our data further showed that knockdown of ubiquitin ligase Skp2 resulted in elevated p27 expression. Importantly, the expression of p27(WT), p27(Y74F), or p27(Y89F) in ACK1-overexpressed 293T cells or ACK1-rescued SAS cells showed higher levels of tyrosyl-phosphorylated p27 and interaction with ACK1 or Skp2. However, the expression of p27(Y88F) mutant exhibited a relatively low phosphorylation level and barely bound with ACK1 or Skp2, showing a basal interaction as the control cells. These results suggested that ACK1 is highly expressed in HNSCC tumors and functions to promote cell proliferation by the phosphorylation and degradation of p27 in the Skp2-mediated mechanism.

14.
BMC Ophthalmol ; 22(1): 43, 2022 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-35093058

RESUMO

BACKGROUND: Amyloidosis is a rare, progressive and variable group of diseases characterized by extracellular deposits of amyloid protein in different tissues and organs. It is a protein-misfolding disease in which small proteins of about 10 to 15 kDa acquire an alternative and relatively misfolded state at minimum energy and subsequently aggregate into oligomers and polymers. It mimics other eyelid diseases, such as involutional ptosis, eyelid granulomatous or cancerous lesions. Misdiagnosis of eyelid amyloidosis is usual when the lesion grows slowly and insidiously. Definite diagnosis depends on clinical suspicion and tissue-proven biopsy. CASE PRESENTATION: A 50-year-old female had painless progressive ptosis in both eyes for 6 months. She presented with limited upward gaze due to swelling of the upper eyelids OU. She complained of mild foreign body sensation. Upon examination, we observed an infiltrated irregular yellowish mass on the surface of her upper palpebral conjunctiva in both eyes. The mass was non-movable without tenderness. We performed excisional biopsy for the masses and subsequent histopathology of the biopsy specimens revealed amyloidosis. Systemic workup showed no other lesions. Unfortunately, her ptosis and upward gaze restriction was not improved after the operation. However, the masses did not enlarge in the following 3 months. CONCLUSIONS: The varied presentations of ocular adnexal and orbital amyloidosis often lead to a significant delay between first symptoms and diagnosis. Immediate confirmatory biopsy and subsequent systemic workup should be performed whenever amyloidosis is highly suspected.


Assuntos
Amiloidose , Blefaroptose , Doenças da Túnica Conjuntiva , Doenças Palpebrais , Amiloidose de Cadeia Leve de Imunoglobulina , Amiloidose/complicações , Amiloidose/diagnóstico , Blefaroptose/diagnóstico , Blefaroptose/etiologia , Doenças Palpebrais/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade
15.
NPJ Regen Med ; 6(1): 74, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34789749

RESUMO

Complex tissue regeneration is extremely rare among adult mammals. An exception, however, is the superior tissue healing of multiple organs in spiny mice (Acomys). While Acomys species exhibit the remarkable ability to heal complex tissue with minimal scarring, little is known about their cardiac structure and response to cardiac injury. In this study, we first examined baseline Acomys cardiac anatomy and function in comparison with commonly used inbred and outbred laboratory Mus strains (C57BL6 and CFW). While our results demonstrated comparable cardiac anatomy and function between Acomys and Mus, Acomys exhibited a higher percentage of cardiomyocytes displaying distinct characteristics. In response to myocardial infarction, all animals experienced a comparable level of initial cardiac damage. However, Acomys demonstrated superior ischemic tolerance and cytoprotection in response to injury as evidenced by cardiac functional stabilization, higher survival rate, and smaller scar size 50 days after injury compared to the inbred and outbred mouse strains. This phenomenon correlated with enhanced endothelial cell proliferation, increased angiogenesis, and medium vessel maturation in the peri-infarct and infarct regions. Overall, these findings demonstrate augmented myocardial preservation in spiny mice post-MI and establish Acomys as a new adult mammalian model for cardiac research.

16.
Indian J Ophthalmol ; 69(6): 1614-1617, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34011754

RESUMO

A 59-year-old woman who underwent uneventful laser in situ keratomileusis surgery 16 years ago presented with traumatic flap dislocation complicated by an epithelial ingrowth in the right eye. The epithelial ingrowth was managed with re-lifting the flap, mechanical debridement, soaking with 70.0% alcohol, and irrigation. The flap was repositioned and secured with a two-part glue technique. Serial anterior segment-optical coherence tomography demonstrated a well-attached flap with no gap or haze in the flap-stromal interface. Three weeks postoperatively, the patient returned to emmetropia and the uncorrected distance visual acuity improved to 20/20. Twelve months postoperatively, the patient's visual acuity remained 20/20, and there was no evidence of recurrent epithelial ingrowth.


Assuntos
Epitélio Corneano , Ceratomileuse Assistida por Excimer Laser In Situ , Epitélio Corneano/cirurgia , Feminino , Humanos , Ceratomileuse Assistida por Excimer Laser In Situ/efeitos adversos , Pessoa de Meia-Idade , Retalhos Cirúrgicos , Transtornos da Visão , Acuidade Visual
18.
Int J Mol Sci ; 22(3)2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33530466

RESUMO

Stem cell-based cardiac therapies have been extensively studied in recent years. However, the efficacy of cell delivery, engraftment, and differentiation post-transplant remain continuous challenges and represent opportunities to further refine our current strategies. Despite limited long-term cardiac retention, stem cell treatment leads to sustained cardiac benefit following myocardial infarction (MI). This review summarizes the current knowledge on stem cell based cardiac immunomodulation by highlighting the cellular and molecular mechanisms of different immune responses to mesenchymal stem cells (MSCs) and their secretory factors. This review also addresses the clinical evidence in the field.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Cardiopatias/terapia , Animais , Terapia Baseada em Transplante de Células e Tecidos/efeitos adversos , Terapia Baseada em Transplante de Células e Tecidos/métodos , Ensaios Clínicos como Assunto , Modelos Animais de Doenças , Cardiopatias/diagnóstico , Cardiopatias/etiologia , Humanos , Imunomodulação , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Mioblastos Cardíacos/citologia , Mioblastos Cardíacos/metabolismo , Regeneração , Transplante de Células-Tronco/métodos , Células-Tronco/citologia , Células-Tronco/metabolismo , Resultado do Tratamento , Cicatrização
19.
ACS Appl Bio Mater ; 4(2): 1655-1667, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35014513

RESUMO

Mesenchymal stem cell (MSC) therapy has been widely tested in clinical trials to promote healing post-myocardial infarction. However, low cell retention and the need for a large donor cell number in human studies remain a key challenge for clinical translation. Natural biomaterials such as gelatin are ideally suited as scaffolds to deliver and enhance cell engraftment after transplantation. A potential drawback of MSC encapsulation in the hydrogel is that the bulky matrix may limit their biological function and interaction with the surrounding tissue microenvironment that conveys important injury signals. To overcome this limitation, we adopted a gelatin methacrylate (gelMA) cell-coating technique that photocross-links gelatin on the individual cell surface at the nanoscale. The present study investigated the cardiac protection of gelMA coated, hypoxia preconditioned MSCs (gelMA-MSCs) in a murine myocardial infarction (MI) model. We demonstrate that the direct injection of gelMA-MSC results in significantly higher myocardial engraftment 7 days after MI compared to uncoated MSCs. GelMA-MSC further amplified MSC benefits resulting in enhanced cardioprotection as measured by cardiac function, scar size, and angiogenesis. Improved MSC cardiac retention also led to a greater cardiac immunomodulatory function after injury. Taken together, this study demonstrated the efficacy of gelMA-MSCs in treating cardiac injury with a promising potential to reduce the need for donor MSCs through enhanced myocardial engraftment.


Assuntos
Sobrevivência Celular/genética , Células-Tronco Mesenquimais/metabolismo , Miocárdio/metabolismo , Animais , Humanos , Camundongos , Polímeros/metabolismo
20.
J Biomed Mater Res A ; 109(3): 326-335, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32491263

RESUMO

Gelatin coatings are effective in increasing the retention of MSCs injected into the heart and minimizing the damage from acute myocardial infarction (AMI), but early studies suffered from low fractions of the MSCs coated with gelatin. Biotinylation of the MSC surface is a critical first step in the gelatin coating process, and in this study, we evaluated the use of biotinylated cholesterol "lipid insertion" anchors as a substitute for the covalent NHS-biotin anchors to the cell surface. Streptavidin-eosin molecules, where eosin is our photoinitiator, can then be bound to the cell surface through biotin-streptavidin affinity. The use of cholesterol anchors increased streptavidin density on the surface of MSCs further driving polymerization and allowing for an increased fraction of MSCs coated with gelatin (83%) when compared to NHS-biotin (52%). Additionally, the cholesterol anchors increased the uniformity of the coating on the MSC surface and supported greater numbers of coated MSCs even when the streptavidin density was slightly lower than that of an NHS-biotin anchoring strategy. Critically, this improvement in gelatin coating efficiency did not impact cytokine secretion and other critical MSC functions. Proper selection of the cholesterol anchor and the biotinylation conditions supports cellular function and densities of streptavidin on the MSC surface of up to ~105 streptavidin molecules/µm2 . In all, these cholesterol anchors offer an effective path towards the formation of conformal coatings on the majority of MSCs to improve the retention of MSCs in the heart following AMI.


Assuntos
Células Imobilizadas/química , Colesterol/química , Gelatina/química , Células-Tronco Mesenquimais/química , Animais , Materiais Biocompatíveis/química , Células Cultivadas , Células Imobilizadas/citologia , Células Imobilizadas/transplante , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/terapia
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