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1.
Nature ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39020175

RESUMO

For healthspan and lifespan, ERK, AMPK and mTORC1 represent critical pathways and inflammation is a centrally important hallmark1-7. Here we examined whether IL-11, a pro-inflammatory cytokine of the IL-6 family, has a negative effect on age-associated disease and lifespan. As mice age, IL-11 is upregulated across cell types and tissues to regulate an ERK-AMPK-mTORC1 axis to modulate cellular, tissue- and organismal-level ageing pathologies. Deletion of Il11 or Il11ra1 protects against metabolic decline, multi-morbidity and frailty in old age. Administration of anti-IL-11 to 75-week-old mice for 25 weeks improves metabolism and muscle function, and reduces ageing biomarkers and frailty across sexes. In lifespan studies, genetic deletion of Il11 extended the lives of mice of both sexes, by 24.9% on average. Treatment with anti-IL-11 from 75 weeks of age until death extends the median lifespan of male mice by 22.5% and of female mice by 25%. Together, these results demonstrate a role for the pro-inflammatory factor IL-11 in mammalian healthspan and lifespan. We suggest that anti-IL-11 therapy, which is currently in early-stage clinical trials for fibrotic lung disease, may provide a translational opportunity to determine the effects of IL-11 inhibition on ageing pathologies in older people.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38884185

RESUMO

Previous studies have shown that the nucleus could offer structural support to the lens capsule. This study investigated the biomechanical performance of porcine lens with and without nucleus for 4 mm, 4.5 mm, 5 mm, 5.5 mm and 6 mm capsulotomy and its potential impact on the stretch ratio of capsular bag when the anterior capsulotomy edge was stretched. Our simulation results showed higher strain for the capsular bag with nucleus, which is crucial for the porcine lens to tolerate more stretch without failure. This simulation could support future study on the optimization of capsulotomy based on patient specific condition, that is, the geometry of lens.

3.
Int J Mol Sci ; 23(13)2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35806094

RESUMO

N-acetyl-p-aminophenol (APAP)-induced liver damage is associated with upregulation of Interleukin-11 (IL11), which is thought to stimulate IL6ST (gp130)-mediated STAT3 activity in hepatocytes, as a compensatory response. However, recent studies have found IL11/IL11RA/gp130 signaling to be hepatotoxic. To investigate further the role of IL11 and gp130 in APAP liver injury, we generated two new mouse strains with conditional knockout (CKO) of either Il11 (CKOIl11) or gp130 (CKOgp130) in adult hepatocytes. Following APAP, as compared to controls, CKOgp130 mice had lesser liver damage with lower serum Alanine Transaminase (ALT) and Aspartate Aminotransferase (AST), greatly reduced serum IL11 levels (90% lower), and lesser centrilobular necrosis. Livers from APAP-injured CKOgp130 mice had lesser ERK, JNK, NOX4 activation and increased markers of regeneration (PCNA, Cyclin D1, Ki67). Experiments were repeated in CKOIl11 mice that, as compared to wild-type mice, had lower APAP-induced ALT/AST, reduced centrilobular necrosis and undetectable IL11 in serum. As seen with CKOgp130 mice, APAP-treated CKOIl11 mice had lesser ERK/JNK/NOX4 activation and greater features of regeneration. Both CKOgp130 and CKOIl11 mice had normal APAP metabolism. After APAP, CKOgp130 and CKOIl11 mice had reduced Il6, Ccl2, Ccl5, Il1ß, and Tnfα expression. These studies exclude IL11 upregulation as compensatory and establish autocrine, self-amplifying, gp130-dependent IL11 secretion from damaged hepatocytes as toxic and anti-regenerative.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Doença Hepática Induzida por Substâncias e Drogas , Acetaminofen/toxicidade , Animais , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Receptor gp130 de Citocina/genética , Receptor gp130 de Citocina/metabolismo , Hepatócitos/metabolismo , Interleucina-11/genética , Interleucina-11/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Necrose/metabolismo
4.
Front Mol Biosci ; 8: 740650, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34651016

RESUMO

In fibroblasts, TGFß1 stimulates IL11 upregulation that leads to an autocrine loop of IL11-dependent pro-fibrotic protein translation. The signaling pathways downstream of IL11, which acts via IL6ST, are contentious with both STAT3 and ERK implicated. Here we dissect IL11 signaling in fibroblasts and study IL11-dependent protein synthesis pathways in the context of approved anti-fibrotic drug mechanisms of action. We show that IL11-induced ERK activation drives fibrogenesis and while STAT3 phosphorylation (pSTAT3) is also seen, this appears unrelated to fibroblast activation. Ironically, recombinant human IL11, which has been used extensively in mouse experiments to infer STAT3 activity downstream of IL11, increases pSTAT3 in Il11ra1 null mouse fibroblasts. Unexpectedly, inhibition of STAT3 was found to induce severe proteotoxic ER stress, generalized fibroblast dysfunction and cell death. In contrast, inhibition of ERK prevented fibroblast activation in the absence of ER stress. IL11 stimulated an axis of ERK/mTOR/P70RSK protein translation and its selectivity for Collagen 1 synthesis was ascribed to an EPRS-regulated, ribosome stalling mechanism. Surprisingly, the anti-fibrotic drug nintedanib caused dose-dependent ER stress and lesser pSTAT3 expression. Pirfenidone had no effect on ER stress whereas anti-IL11 specifically inhibited the ERK/mTOR axis while reducing ER stress. These studies define the translation-specific signaling pathways downstream of IL11, intersect immune and metabolic signaling and reveal unappreciated effects of nintedanib.

5.
Rheumatology (Oxford) ; 60(12): 5820-5826, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33590875

RESUMO

OBJECTIVES: Interleukin 11 (IL11) is highly upregulated in skin and lung fibroblasts from patients with systemic sclerosis (SSc). Here we tested whether IL11 is mechanistically linked with activation of human dermal fibroblasts (HDFs) from patients with SSc or controls. METHODS: We measured serum IL11 levels in volunteers and patients with early diffuse SSc and manipulated IL11 signalling in HDFs using gain- and loss-of-function approaches that we combined with molecular and cellular phenotyping. RESULTS: In patients with SSc, serum IL11 levels are elevated as compared with healthy controls. All transforming growth factor beta (TGFß) isoforms induced IL11 secretion from HDFs, which highly express IL11 receptor α-subunit and the glycoprotein 130 (gp130) co-receptor, suggestive of an autocrine loop of IL11 activity in HDFs. IL11 stimulated ERK activation in HDFs and resulted in HDF-to-myofibroblast transformation and extracellular matrix secretion. The pro-fibrotic action of IL11 in HDFs appeared unrelated to STAT3 activity, independent of TGFß upregulation and was not associated with phosphorylation of SMAD2/3. Inhibition of IL11 signalling using either a neutralizing antibody against IL11 or siRNA against IL11RA reduced TGFß-induced HDF proliferation, matrix production and cell migration, which was phenocopied by pharmacological inhibition of ERK. CONCLUSIONS: These data reveal that autocrine IL11-dependent ERK activity alone or downstream of TGFß stimulation promotes fibrosis phenotypes in dermal fibroblasts and suggest IL11 as a potential therapeutic target in SSc.


Assuntos
Regulação da Expressão Gênica , Subunidade alfa de Receptor de Interleucina-11/genética , Interleucina-11/sangue , Sistema de Sinalização das MAP Quinases/genética , RNA/genética , Escleroderma Sistêmico/sangue , Pele/patologia , Biomarcadores/sangue , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Humanos , Subunidade alfa de Receptor de Interleucina-11/biossíntese , Escleroderma Sistêmico/genética , Escleroderma Sistêmico/patologia , Transdução de Sinais
6.
Sci Rep ; 10(1): 7402, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32366916

RESUMO

The advent of cell culture-based methods for the establishment and expansion of human corneal endothelial cells (CEnC) has provided a source of transplantable corneal endothelium, with a significant potential to challenge the one donor-one recipient paradigm. However, concerns over cell identity remain, and a comprehensive characterization of the cultured CEnC across serial passages has not been performed. To this end, we compared two established CEnC culture methods by assessing the transcriptomic changes that occur during in vitro expansion. In confluent monolayers, low mitogenic culture conditions preserved corneal endothelial cell state identity better than culture in high mitogenic conditions. Expansion by continuous passaging induced replicative cell senescence. Transcriptomic analysis of the senescent phenotype identified a cell senescence signature distinct for CEnC. We identified activation of both classic and new cell signaling pathways that may be targeted to prevent senescence, a significant barrier to realizing the potential clinical utility of in vitro expansion.


Assuntos
Técnicas de Cultura de Células/métodos , Endotélio Corneano/citologia , Adolescente , Adulto , Movimento Celular , Proliferação de Células , Senescência Celular , Criança , Pré-Escolar , Biologia Computacional , Transplante de Córnea , Feminino , Humanos , Masculino , Fenótipo , Transdução de Sinais , Transcriptoma , Adulto Jovem
7.
Circulation ; 140(11): 937-951, 2019 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-31284728

RESUMO

BACKGROUND: Fibrosis is a common pathology in many cardiac disorders and is driven by the activation of resident fibroblasts. The global posttranscriptional mechanisms underlying fibroblast-to-myofibroblast conversion in the heart have not been explored. METHODS: Genome-wide changes of RNA transcription and translation during human cardiac fibroblast activation were monitored with RNA sequencing and ribosome profiling. We then used RNA-binding protein-based analyses to identify translational regulators of fibrogenic genes. The integration with cardiac ribosome occupancy levels of 30 dilated cardiomyopathy patients demonstrates that these posttranscriptional mechanisms are also active in the diseased fibrotic human heart. RESULTS: We generated nucleotide-resolution translatome data during the transforming growth factor ß1-driven cellular transition of human cardiac fibroblasts to myofibroblasts. This identified dynamic changes of RNA transcription and translation at several time points during the fibrotic response, revealing transient and early-responder genes. Remarkably, about one-third of all changes in gene expression in activated fibroblasts are subject to translational regulation, and dynamic variation in ribosome occupancy affects protein abundance independent of RNA levels. Targets of RNA-binding proteins were strongly enriched in posttranscriptionally regulated genes, suggesting genes such as MBNL2 can act as translational activators or repressors. Ribosome occupancy in the hearts of patients with dilated cardiomyopathy suggested the same posttranscriptional regulatory network was underlying cardiac fibrosis. Key network hubs include RNA-binding proteins such as Pumilio RNA binding family member 2 (PUM2) and Quaking (QKI) that work in concert to regulate the translation of target transcripts in human diseased hearts. Furthermore, silencing of both PUM2 and QKI inhibits the transition of fibroblasts toward profibrotic myofibroblasts in response to transforming growth factor ß1. CONCLUSIONS: We reveal widespread translational effects of transforming growth factor ß1 and define novel posttranscriptional regulatory networks that control the fibroblast-to-myofibroblast transition. These networks are active in human heart disease, and silencing of hub genes limits fibroblast activation. Our findings show the central importance of translational control in fibrosis and highlight novel pathogenic mechanisms in heart failure.


Assuntos
Cardiopatias/genética , Cardiopatias/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Biossíntese de Proteínas/genética , Proteínas de Ligação a RNA/genética , Células Cultivadas , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose/genética , Fibrose/metabolismo , Fibrose/patologia , Perfilação da Expressão Gênica/métodos , Cardiopatias/patologia , Humanos , Análise de Sequência de RNA/métodos , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo
8.
Arterioscler Thromb Vasc Biol ; 39(3): 387-401, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30651003

RESUMO

Objective- Atherosclerotic coronary artery disease is the leading cause of death worldwide, and current treatment options are insufficient. Using systems-level network cluster analyses on a large coronary artery disease case-control cohort, we previously identified PCSK3 (proprotein convertase subtilisin/kexin family member 3; FURIN) as a member of several coronary artery disease-associated pathways. Thus, our objective is to determine the role of FURIN in atherosclerosis. Approach and Results- In vitro, FURIN inhibitor treatment resulted in reduced monocyte migration and reduced macrophage and vascular endothelial cell inflammatory and cytokine gene expression. In vivo, administration of an irreversible inhibitor of FURIN, α-1-PDX (α1-antitrypsin Portland), to hyperlipidemic Ldlr-/- mice resulted in lower atherosclerotic lesion area and a specific reduction in severe lesions. Significantly lower lesional macrophage and collagen area, as well as systemic inflammatory markers, were observed. MMP2 (matrix metallopeptidase 2), an effector of endothelial function and atherosclerotic lesion progression, and a FURIN substrate was significantly reduced in the aorta of inhibitor-treated mice. To determine FURIN's role in vascular endothelial function, we administered α-1-PDX to Apoe-/- mice harboring a wire injury in the common carotid artery. We observed significantly decreased carotid intimal thickness and lower plaque cellularity, smooth muscle cell, macrophage, and inflammatory marker content, suggesting protection against vascular remodeling. Overexpression of FURIN in this model resulted in a significant 67% increase in intimal plaque thickness, confirming that FURIN levels directly correlate with atherosclerosis. Conclusions- We show that systemic inhibition of FURIN in mice decreases vascular remodeling and atherosclerosis. FURIN-mediated modulation of MMP2 activity may contribute to the atheroprotection observed in these mice.


Assuntos
Aterosclerose/prevenção & controle , Furina/antagonistas & inibidores , Placa Aterosclerótica/tratamento farmacológico , alfa 1-Antitripsina/uso terapêutico , Animais , Aorta/enzimologia , Aterosclerose/genética , Aterosclerose/patologia , Artéria Carótida Primitiva , Progressão da Doença , Avaliação Pré-Clínica de Medicamentos , Indução Enzimática/efeitos dos fármacos , Furina/genética , Furina/fisiologia , Regulação da Expressão Gênica/efeitos dos fármacos , Macrófagos/fisiologia , Masculino , Metaloproteinase 2 da Matriz/análise , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/fisiologia , Placa Aterosclerótica/patologia , Receptores de LDL/deficiência , Túnica Íntima/efeitos dos fármacos , Túnica Íntima/patologia , Remodelação Vascular , alfa 1-Antitripsina/farmacologia
9.
Sci Rep ; 7(1): 14149, 2017 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-29074873

RESUMO

Corneal transplantation is the only treatment available to restore vision for individuals with blindness due to corneal endothelial dysfunction. However, severe shortage of available donor corneas remains a global challenge. Functional regulatory compliant tissue-engineered corneal endothelial graft substitute can alleviate this reliance on cadaveric corneal graft material. Here, isolated primary human corneal endothelial cells (CEnCs) propagated using a dual media approach refined towards regulatory compliance showed expression of markers indicative of the human corneal endothelium, and can be tissue-engineered onto thin corneal stromal carriers. Both cellular function and clinical adaptability was demonstrated in a pre-clinical rabbit model of bullous keratopathy using a tissue-engineered endothelial keratoplasty (TE-EK) approach, adapted from routine endothelial keratoplasty procedure for corneal transplantation in human patients. Cornea thickness of rabbits receiving TE-EK graft gradually reduced over the first two weeks, and completely recovered to a thickness of approximately 400 µm by the third week of transplantation, whereas corneas of control rabbits remained significantly thicker over 1,000 µm (p < 0.05) throughout the course of the study. This study showed convincing evidence of the adaptability of the propagated CEnCs and their functionality via a TE-EK approach, which holds great promises in translating the use of cultured CEnCs into the clinic.


Assuntos
Técnicas de Cultura de Células/métodos , Doenças da Córnea/terapia , Transplante de Córnea/métodos , Endotélio Corneano/citologia , Endotélio Corneano/transplante , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Substância Própria/citologia , Criopreservação/métodos , Modelos Animais de Doenças , Matriz Extracelular , Feminino , Humanos , Masculino , Coelhos , Engenharia Tecidual/métodos
10.
Invest Ophthalmol Vis Sci ; 58(11): 4490-4498, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28873174

RESUMO

Purpose: To determine the effects of the Ziemer LDV Z8 liquid interface femtosecond laser platform during capsulotomy under different energy settings in the presence of corneal edema. Methods: Cadaveric porcine eyes (n = 36) employed at less than 6 and greater than 24 post enucleation hours to simulate clear/edematous corneas, underwent capsulotomy with the Ziemer LDV Z8 femtosecond laser (5-mm diameter, energy 90%, 130%, or 150%). Lens capsules were removed for evaluation by scanning electron microscopy and rupture strengths determined by the single column universal testing system. Following ethical approval, 23 patients had lens capsules removed during routine cataract surgery following manual or Z8 capsulotomy and subjected to TUNEL assay. Results: There was no difference in edge morphology or rupture strength (120, 113, and 118 mN at increasing energy, P = 0.42) in the clear cornea. Only 50% of capsulotomies succeeded at 90% energy in an edematous cornea, improving with increased energy (75% completion at 130%, 100% at 150%). Rupture strength in edematous corneas was not significantly different at 112, 133, and 114 mN for 90%, 130%, and 150%, respectively (P = 0.3). In human samples, increased TUNEL-positive cells were seen at 130% energy, but not at 150% (0.0 manual vs. 0.2 [90%] vs. 2.1 [130%] vs. 0.6 [150%], P < 0.05). Conclusions: Because of the low energy delivered by a femtosecond nanojoule platform, even incremental increases in energy appeared to have minimal effect on lens capsule morphology and strength and negligible influence on cell death. Furthermore, increasing energy appeared to enhance consistency and the ability to complete a capsulotomy in an edematous cornea.


Assuntos
Cápsula Anterior do Cristalino/cirurgia , Capsulorrexe/métodos , Edema da Córnea/complicações , Terapia a Laser/métodos , Facoemulsificação/métodos , Idoso , Idoso de 80 Anos ou mais , Animais , Cápsula Anterior do Cristalino/ultraestrutura , Modelos Animais de Doenças , Humanos , Marcação In Situ das Extremidades Cortadas , Implante de Lente Intraocular , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Suínos
11.
Sci Rep ; 5: 9167, 2015 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-25823914

RESUMO

The global shortage of donor corneas has garnered extensive interest in the development of graft alternatives suitable for endothelial keratoplasty using cultivated primary human corneal endothelial cells (CECs). We have recently described a dual media approach for the propagation of human CECs. In this work, we characterize the effects of a Rho-kinase inhibitor Y-27632 on the cultivation of CECs propagated using the dual media culture system. Seventy donor corneas deemed unsuitable for transplantation were procured for this study. We assessed the use of Y-27632 for its effect at each stage of the cell culture process, specifically for cell attachment, cell proliferation, and during both regular passaging and cryopreservation. Lastly, comparison of donor-matched CEC-cultures expanded with or without Y-27632 was also performed. Our results showed that Y-27632 significantly improved the attachment and proliferation of primary CECs. A non-significant pro-survival effect was detected during regular cellular passage when CECs were pre-treated with Y-27632, an effect that became more evident during cryopreservation. Our study showed that the inclusion of Y-27632 was beneficial for the propagation of primary CECs expanded via the dual media approach, and was able to increase overall cell yield by between 1.96 to 3.36 fold.


Assuntos
Amidas/farmacologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Endotélio Corneano/citologia , Piridinas/farmacologia , Quinases Associadas a rho/antagonistas & inibidores , Adolescente , Adulto , Adesão Celular/efeitos dos fármacos , Técnicas de Cultura de Células , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Criança , Pré-Escolar , Criopreservação , Feminino , Humanos , Masculino , Adulto Jovem
12.
Cell Transplant ; 24(2): 287-304, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24268186

RESUMO

Corneal endothelium-associated corneal blindness is the most common indication for corneal transplantation. Restorative corneal transplant surgery is the only option to reverse the blindness, but a global shortage of donor material remains an issue. There are immense clinical interests in the development of alternative treatment strategies to alleviate current reliance on donor materials. For such endeavors, ex vivo propagation of human corneal endothelial cells (hCECs) is required, but current methodology lacks consistency, with expanded hCECs losing cellular morphology to a mesenchymal-like transformation. In this study, we describe a novel dual media culture approach for the in vitro expansion of primary hCECs. Initial characterization included analysis of growth dynamics of hCECs grown in either proliferative (M4) or maintenance (M5) medium. Subsequent comparisons were performed on isolated hCECs cultured in M4 alone against cells expanded using the dual media approach. Further characterizations were performed using immunocytochemistry, quantitative real-time PCR, and gene expression microarray. At the third passage, results showed that hCECs propagated using the dual media approach were homogeneous in appearance, retained their unique polygonal cellular morphology, and expressed higher levels of corneal endothelium-associated markers in comparison to hCECs cultured in M4 alone, which were heterogeneous and fibroblastic in appearance. Finally, for hCECs cultured using the dual media approach, global gene expression and pathway analysis between confluent hCECs before and after 7-day exposure to M5 exhibited differential gene expression associated predominately with cell proliferation and wound healing. These findings showed that the propagation of primary hCECs using the novel dual media approach presented in this study is a consistent method to obtain bona fide hCECs. This, in turn, will elicit greater confidence in facilitating downstream development of alternative corneal endothelium replacement using tissue-engineered graft materials or cell injection therapy.


Assuntos
Proliferação de Células/efeitos dos fármacos , Meios de Cultura/farmacologia , Endotélio Corneano/metabolismo , Adolescente , Adulto , Células Cultivadas , Pré-Escolar , Regulação para Baixo , Endotélio Corneano/citologia , Endotélio Corneano/efeitos dos fármacos , Feminino , Humanos , Imuno-Histoquímica , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima , Adulto Jovem
13.
PLoS One ; 9(6): e100563, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24949869

RESUMO

Corneal endothelial transplantation or endothelial keratoplasty has become the preferred choice of transplantation for patients with corneal blindness due to endothelial dysfunction. Currently, there is a worldwide shortage of transplantable tissue, and demand is expected to increase further with aging populations. Tissue-engineered alternatives are being developed, and are likely to be available soon. However, the cost of these constructs may impair their widespread use. A cost-minimization analysis comparing tissue-engineered constructs to donor tissue procured from eye banks for endothelial keratoplasty was performed. Both initial investment costs and recurring costs were considered in the analysis to arrive at a final tissue cost per transplant. The clinical outcomes of endothelial keratoplasty with tissue-engineered constructs and with donor tissue procured from eye banks were assumed to be equivalent. One-way and probabilistic sensitivity analyses were performed to simulate various possible scenarios, and to determine the robustness of the results. A tissue engineering strategy was cheaper in both investment cost and recurring cost. Tissue-engineered constructs for endothelial keratoplasty could be produced at a cost of US$880 per transplant. In contrast, utilizing donor tissue procured from eye banks for endothelial keratoplasty required US$3,710 per transplant. Sensitivity analyses performed further support the results of this cost-minimization analysis across a wide range of possible scenarios. The use of tissue-engineered constructs for endothelial keratoplasty could potentially increase the supply of transplantable tissue and bring the costs of corneal endothelial transplantation down, making this intervention accessible to a larger group of patients. Tissue-engineering strategies for corneal epithelial constructs or other tissue types, such as pancreatic islet cells, should also be subject to similar pharmacoeconomic analyses.


Assuntos
Cegueira/economia , Doenças da Córnea/economia , Transplante de Córnea/economia , Custos e Análise de Custo , Cegueira/patologia , Cegueira/terapia , Córnea/patologia , Doenças da Córnea/patologia , Doenças da Córnea/terapia , Endotélio Corneano/patologia , Endotélio Corneano/transplante , Bancos de Olhos , Humanos , Doadores de Tecidos , Engenharia Tecidual/economia
14.
BMC Res Notes ; 6: 176, 2013 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-23641909

RESUMO

BACKGROUND: Global shortage of donor corneas greatly restricts the numbers of corneal transplantations performed yearly. Limited ex vivo expansion of primary human corneal endothelial cells is possible, and a considerable clinical interest exists for development of tissue-engineered constructs using cultivated corneal endothelial cells. The objective of this study was to investigate the density-dependent growth of human corneal endothelial cells isolated from paired donor corneas and to elucidate an optimal seeding density for their extended expansion in vitro whilst maintaining their unique cellular morphology. RESULTS: Established primary human corneal endothelial cells were propagated to the second passage (P2) before they were utilized for this study. Confluent P2 cells were dissociated and seeded at four seeding densities: 2,500 cells per cm2 ('LOW'); 5,000 cells per cm2 ('MID'); 10,000 cells per cm2 ('HIGH'); and 20,000 cells per cm2 ('HIGH(×2)'), and subsequently analyzed for their propensity to proliferate. They were also subjected to morphometric analyses comparing cell sizes, coefficient of variance, as well as cell circularity when each culture became confluent. At the two lower densities, proliferation rates were higher than cells seeded at higher densities, though not statistically significant. However, corneal endothelial cells seeded at lower densities were significantly larger in size, heterogeneous in shape and less circular (fibroblastic-like), and remained hypertrophic after one month in culture. Comparatively, cells seeded at higher densities were significantly homogeneous, compact and circular at confluence. Potentially, at an optimal seeding density of 10,000 cells per cm2, it is possible to obtain between 10 million to 25 million cells at the third passage. More importantly, these expanded human corneal endothelial cells retained their unique cellular morphology. CONCLUSIONS: Our results demonstrated a density dependency in the culture of primary human corneal endothelial cells. Sub-optimal seeding density results in a decrease in cell saturation density, as well as a loss in their proliferative potential. As such, we propose a seeding density of not less than 10,000 cells per cm2 for regular passage of primary human corneal endothelial cells.


Assuntos
Córnea/citologia , Endotélio/citologia , Proliferação de Células , Células Cultivadas , Humanos , Técnicas In Vitro
15.
Oncol Res ; 14(10): 513-27, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15559765

RESUMO

Akt, a serine/threonine kinase that promotes cell survival, is activated by binding of its pleckstrin homology (PH) domain to membrane phosphatidylinositol (PtdIns)-3-phosphates formed by PtdIns-3-kinase. D-3-Deoxy-phosphatidyl-myo-inositols that cannot be phosphorylated on the 3-position of the myo-inositol group are inhibitors of the Akt PH domain. The most active compound is D-3-deoxy-phosphatidyl-myo-inositol 1-[(R)-2-methoxy-3-octadecyloxypropyl hydrogen phosphate] (PX-316). PX-316 administered intraperitoneally to mice at 150 mg/kg inhibits Akt activation in HT-29 human tumor xenografts up to 78% at 10 h with recovery to 34% at 48 h. Phosphorylation of GSK-3beta, a downstream target of Akt, is also inhibited. There is no decrease in PtdIns(3,4,5)-trisphosphate levels by PX-316, showing it is not an inhibitor of PtdIns-3-K in vivo. Gene expression profiling of HT-29 tumor xenografts shows many similarities between the effects of PX-316 and the PtdIns-3-K inhibitor wortmannin, with downregulation of several ribosomal-related genes, while PX-316 uniquely increases the expression of a group of mitochondrial-related genes. PX-316 has antitumor activity against early human MCF-7 breast cancer and HT-29 colon cancer xenografts in mice. PX-316 formulated in 20% hydroxypropyl-beta-cyclodextrin for intravenous administration is well tolerated in mice and rats with no hemolysis and no hematological toxicity. Thus, PX-316 is the lead compound of a new class of potential agents that inhibit Akt survival signaling.


Assuntos
Inibidores Enzimáticos/farmacologia , Regulação Neoplásica da Expressão Gênica , Fosfatos de Inositol/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , 2-Hidroxipropil-beta-Ciclodextrina , Androstadienos/farmacologia , Animais , Antineoplásicos/farmacologia , Sítios de Ligação , Linhagem Celular Tumoral , Sobrevivência Celular , Relação Dose-Resposta a Droga , Regulação para Baixo , Ativação Enzimática , Humanos , Concentração Inibidora 50 , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos SCID , Mitocôndrias/metabolismo , Modelos Químicos , Modelos Moleculares , Transplante de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Ligação Proteica , Conformação Proteica , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-akt , Serina/química , Transdução de Sinais , Fatores de Tempo , Wortmanina , beta-Ciclodextrinas/química
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