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1.
Arterioscler Thromb Vasc Biol ; 43(8): 1412-1428, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37317853

RESUMO

BACKGROUND: During infectious diseases, proinflammatory cytokines transiently destabilize interactions between adjacent vascular endothelial cells (ECs) to facilitate the passage of immune molecules and cells into tissues. However, in the lung, the resulting vascular hyperpermeability can lead to organ dysfunction. Previous work identified the transcription factor ERG (erythroblast transformation-specific-related gene) as a master regulator of endothelial homeostasis. Here we investigate whether the sensitivity of pulmonary blood vessels to cytokine-induced destabilization is due to organotypic mechanisms affecting the ability of endothelial ERG to protect lung ECs from inflammatory injury. METHODS: Cytokine-dependent ubiquitination and proteasomal degradation of ERG were analyzed in cultured HUVECs (human umbilical vein ECs). Systemic administration of TNFα (tumor necrosis factor alpha) or the bacterial cell wall component lipopolysaccharide was used to cause a widespread inflammatory challenge in mice; ERG protein levels were assessed by immunoprecipitation, immunoblot, and immunofluorescence. Murine Erg deletion was genetically induced in ECs (Ergfl/fl;Cdh5[PAC]-CreERT2), and multiple organs were analyzed by histology, immunostaining, and electron microscopy. RESULTS: In vitro, TNFα promoted the ubiquitination and degradation of ERG in HUVECs, which was blocked by the proteasomal inhibitor MG132. In vivo, systemic administration of TNFα or lipopolysaccharide resulted in a rapid and substantial degradation of ERG within lung ECs but not ECs of the retina, heart, liver, or kidney. Pulmonary ERG was also downregulated in a murine model of influenza infection. Ergfl/fl;Cdh5(PAC)-CreERT2 mice spontaneously recapitulated aspects of inflammatory challenges, including lung-predominant vascular hyperpermeability, immune cell recruitment, and fibrosis. These phenotypes were associated with a lung-specific decrease in the expression of Tek-a gene target of ERG previously implicated in maintaining pulmonary vascular stability during inflammation. CONCLUSIONS: Collectively, our data highlight a unique role for ERG in pulmonary vascular function. We propose that cytokine-induced ERG degradation and subsequent transcriptional changes in lung ECs play critical roles in the destabilization of pulmonary blood vessels during infectious diseases.


Assuntos
Doenças Transmissíveis , Fatores de Transcrição , Humanos , Camundongos , Animais , Fatores de Transcrição/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Lipopolissacarídeos/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Citocinas/metabolismo , Doenças Transmissíveis/metabolismo , Células Cultivadas , Regulador Transcricional ERG/genética , Regulador Transcricional ERG/metabolismo
2.
Circ Res ; 124(9): 1337-1349, 2019 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-30892142

RESUMO

RATIONALE: The ETS (E-26 transformation-specific) transcription factor ERG (ETS-related gene) is essential for endothelial homeostasis, driving expression of lineage genes and repressing proinflammatory genes. Loss of ERG expression is associated with diseases including atherosclerosis. ERG's homeostatic function is lineage-specific, because aberrant ERG expression in cancer is oncogenic. The molecular basis for ERG lineage-specific activity is unknown. Transcriptional regulation of lineage specificity is linked to enhancer clusters (super-enhancers). OBJECTIVE: To investigate whether ERG regulates endothelial-specific gene expression via super-enhancers. METHODS AND RESULTS: Chromatin immunoprecipitation with high-throughput sequencing in human umbilical vein endothelial cells showed that ERG binds 93% of super-enhancers ranked according to H3K27ac, a mark of active chromatin. These were associated with endothelial genes such as DLL4 (Delta-like protein 4), CLDN5 (claudin-5), VWF (von Willebrand factor), and CDH5 (VE-cadherin). Comparison between human umbilical vein endothelial cell and prostate cancer TMPRSS2 (transmembrane protease, serine-2):ERG fusion-positive human prostate epithelial cancer cell line (VCaP) cells revealed distinctive lineage-specific transcriptome and super-enhancer profiles. At a subset of endothelial super-enhancers (including DLL4 and CLDN5), loss of ERG results in significant reduction in gene expression which correlates with decreased enrichment of H3K27ac and MED (Mediator complex subunit)-1, and reduced recruitment of acetyltransferase p300. At these super-enhancers, co-occupancy of GATA2 (GATA-binding protein 2) and AP-1 (activator protein 1) is significantly lower compared with super-enhancers that remained constant following ERG inhibition. These data suggest distinct mechanisms of super-enhancer regulation in endothelial cells and highlight the unique role of ERG in controlling a core subset of super-enhancers. Most disease-associated single nucleotide polymorphisms from genome-wide association studies lie within noncoding regions and perturb transcription factor recognition sequences in relevant cell types. Analysis of genome-wide association studies data shows significant enrichment of risk variants for cardiovascular disease and other diseases, at ERG endothelial enhancers and super-enhancers. CONCLUSIONS: The transcription factor ERG promotes endothelial homeostasis via regulation of lineage-specific enhancers and super-enhancers. Enrichment of cardiovascular disease-associated single nucleotide polymorphisms at ERG super-enhancers suggests that ERG-dependent transcription modulates disease risk.


Assuntos
Elementos Facilitadores Genéticos/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Linhagem Celular Tumoral , Células Cultivadas , Claudina-5/genética , Claudina-5/metabolismo , Fator de Transcrição GATA2/genética , Fator de Transcrição GATA2/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/metabolismo , Regulador Transcricional ERG/genética
3.
J Obstet Gynaecol Res ; 47(10): 3464-3470, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34342089

RESUMO

BACKGROUND: There is limited clinical evidence of ferric carboxymaltose injection (FCM) usage in Indian pregnant women. We assessed the efficacy and safety of FCM in Indian pregnant women with moderate-to-severe anemia. METHODS: Single-center, retrospective, observational data collection was conducted at a tertiary care research institute. Data of pregnant women with anemia who received FCM in their second and third trimester was retrieved and analyzed for hematological parameters at baseline and at 4 ± 2 weeks. Neonatal outcomes were also assessed. Adverse events and other safety parameters were noted. RESULTS: Data of 271 patients was retrieved and analyzed for safety and data for 168 patients analyzed for efficacy. A significant increase in hemoglobin was noted with FCM in 4 weeks (1.25 g/dL; p < 0.001). Patients with severe anemia reported an increase in hemoglobin of 4.23 g/dL (p = 0.01). Patients receiving FCM in the second trimester noted a significant increase in hemoglobin of 1.74 g/dL (p < 0.001). A significant increase in hemoglobin was noted as early as 20 days (p < 0.001) and also in patients receiving FCM after 34 weeks (p = 0.002). No adverse fetal or neonatal outcomes were observed. Adverse events noted in 4% of patients with itching and rash being most common. Continuous monitoring of blood pressure, heart rate, and oxygen saturation for 40 min during and after FCM administration reported no deterioration or negative safety signal. CONCLUSION: FCM corrects anemia in all subsets of Indian pregnant women and supports evidence of efficacy and safety. Continuous monitoring of vital parameters during FCM infusions supports its excellent safety.


Assuntos
Anemia Ferropriva , Feminino , Compostos Férricos/efeitos adversos , Humanos , Recém-Nascido , Maltose/efeitos adversos , Maltose/análogos & derivados , Gravidez , Estudos Retrospectivos , Resultado do Tratamento
4.
Ultraschall Med ; 41(5): 550-556, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31238385

RESUMO

OBJECTIVE: To evaluate the middle-term efficacy and complications of ultrasound-guided high intensity focused ultrasound (USgHIFU) for the treatment of symptomatic uterine fibroids in an NHS population. METHODS: A prospective observational single-center study at a single university hospital in Oxford, UK. Patients with symptomatic uterine fibroids who declined standard surgical/radiological intervention and were referred to the HIFU unit were considered for USgHIFU treatment. Clinical evaluation, adverse event monitoring, uterine fibroid symptoms and health-related quality of life questionnaire (UFS-QOL) and contrast-enhanced pelvic magnetic resonance imaging (MRI) were performed before and at regular intervals after treatment to assess patient outcome. RESULTS: 12 of 22 referred patients underwent one session of USgHIFU ablation of 14 fibroids overall and received a two-year follow-up. No serious adverse events were reported, but a second-degree skin burn was observed in one patient who had a surgical scar from a previous caesarean section. Mean symptom severity scores (SSS-QOL) improved significantly from 56.5 ±â€Š29.1 (SD) at baseline to 33.4 ±â€Š23.3 (p < 0.01) at three months, 45.0 ±â€Š35.4 (p < 0.05) at one year and 40.6 ± 32.7 (p < 0.01) at two years post-treatment. The mean non-perfused volume ratio was 67.7 ±â€Š39.0 % (SD) in the treated fibroids (n = 14) within three months of treatment. The mean volume reduction rates of the treated fibroids were 23.3 ± 25.5 % (SD) at 3 months post-treatment (p < 0.01, n = 14), 49.3 ± 23.7 % at 12 months (p < 0.05, n = 8), and 51.9 ±â€Š11.1 % at 24 months (p < 0.005, n = 8). CONCLUSION: This study demonstrates the clinical efficacy of USgHIFU ablation of uterine fibroids and the low risk of complications. We believe that this noninvasive approach may offer an alternative therapy for women with symptomatic uterine fibroids. While HIFU is fast becoming the standard of care for fibroid ablation in other countries, to our knowledge, this study is the first to present clinical experience of US-guided HIFU ablation of symptomatic uterine fibroids in an NHS population. PLAIN LANGUAGE SUMMARY: High intensity focused ultrasound (HIFU) can be used for the noninvasive ablation of symptomatic uterine fibroids, and MR-guided treatment has already gained FDA approval. Ultrasound-guided HIFU has the advantage of offering practicalities in anesthesia and considerable cost-savings over MR-guided treatments. In this prospective study we have demonstrated the middle-term efficacy and favorable safety profile of ultrasound-guided HIFU for the treatment of symptomatic uterine fibroids for the first time in an NHS population.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Leiomioma , Neoplasias Uterinas , Cesárea , Feminino , Humanos , Leiomioma/diagnóstico por imagem , Leiomioma/terapia , Imageamento por Ressonância Magnética , Gravidez , Estudos Prospectivos , Qualidade de Vida , Resultado do Tratamento , Ultrassonografia de Intervenção , Neoplasias Uterinas/diagnóstico por imagem , Neoplasias Uterinas/terapia
5.
Circulation ; 138(14): 1446-1462, 2018 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-29643057

RESUMO

BACKGROUND: Atherosclerotic plaques demonstrate extensive accumulation of oxidative DNA damage, predominantly as 8-oxoguanine (8oxoG) lesions. 8oxoG is repaired by base excision repair enzymes; however, the mechanisms regulating 8oxoG accumulation in vascular smooth muscle cells (VSMCs) and its effects on their function and in atherosclerosis are unknown. METHODS: We studied levels of 8oxoG and its regulatory enzymes in human atherosclerosis, the mechanisms regulating 8oxoG repair and the base excision repair enzyme 8oxoG DNA glycosylase I (OGG1) in VSMCs in vitro, and the effects of reducing 8oxoG in VSMCs in atherosclerosis in ApoE-/- mice. RESULTS: Human plaque VSMCs showed defective nuclear 8oxoG repair, associated with reduced acetylation of OGG1. OGG1 was a key regulatory enzyme of 8oxoG repair in VSMCs, and its acetylation was crucial to its repair function through regulation of protein stability and expression. p300 and sirtuin 1 were identified as the OGG1 acetyltransferase and deacetylase regulators, respectively, and both proteins interacted with OGG1 and regulated OGG1 acetylation at endogenous levels. However, p300 levels were decreased in human plaque VSMCs and in response to oxidative stress, suggesting that reactive oxygen species-induced regulation of OGG1 acetylation could be caused by reactive oxygen species-induced decrease in p300 expression. We generated mice that express VSMC-restricted OGG1 or an acetylation defective version (SM22α-OGG1 and SM22α-OGG1K-R mice) and crossed them with ApoE-/- mice. We also studied ApoE-/- mice deficient in OGG1 (OGG1-/-). OGG1-/- mice showed increased 8oxoG in vivo and increased atherosclerosis, whereas mice expressing VSMC-specific OGG1 but not the acetylation mutant OGG1K-R showed markedly reduced intracellular 8oxoG and reduced atherosclerosis. VSMC OGG1 reduced telomere 8oxoG accumulation, DNA strand breaks, cell death and senescence after oxidant stress, and activation of proinflammatory pathways. CONCLUSIONS: We identify defective 8oxoG base excision repair in human atherosclerotic plaque VSMCs, OGG1 as a major 8oxoG repair enzyme in VSMCs, and p300/sirtuin 1 as major regulators of OGG1 through acetylation/deacetylation. Reducing oxidative damage by rescuing OGG1 activity reduces plaque development, indicating the detrimental effects of 8oxoG on VSMC function.


Assuntos
Aterosclerose/metabolismo , Dano ao DNA , DNA Glicosilases/metabolismo , Reparo do DNA , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Estresse Oxidativo , Placa Aterosclerótica , Acetilação , Animais , Aterosclerose/genética , Aterosclerose/patologia , Biomarcadores/metabolismo , Células Cultivadas , DNA Glicosilases/deficiência , DNA Glicosilases/genética , Modelos Animais de Doenças , Feminino , Guanina/análogos & derivados , Guanina/metabolismo , Humanos , Masculino , Camundongos Knockout para ApoE , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , Processamento de Proteína Pós-Traducional , Ratos , Sirtuína 1/genética , Sirtuína 1/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo
6.
Pharm Res ; 36(8): 122, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31218556

RESUMO

PURPOSE: A non-propellant based foam (NPF) system was developed incorporating the antibiotics, pectin capped green nano-silver and sulfadiazine (SD) for the topical treatment of burn wounds as a convenient alternative to the existing therapies. METHODS: NPF were prepared using various surfactants and oils forming a nanoemulsion. Anti-microbial studies by resazurin microtitre assay, ex vivo diffusion, in vivo skin permeation and deposition studies, and acute irritation studies were carried out. NPF was applied onto secondary thermal wounds manifested on mice models followed by macroscopic and histological examinations. RESULTS: NPF had an average globule size of <75 nm. The viscosity was ~10 cP indicating the feasibility of expulsion from the container upon actuation. With no skin irritation, the foams showed a higher skin deposition of SD. A high contraction and an evident regeneration of the skin tissue upon treatment with NPF indicated a good recovery from the thermal injury was apparent from the histology studies. CONCLUSION: NPF represents an alternative topical formulation that can be employed as a safe and effective treatment modality for superficial second degree (partial thickness) burn wounds. With a minimal requirement of mechanical force, the no-touch application of NPF makes it suitable for sensitive and irritant skin surfaces.


Assuntos
Antibacterianos/farmacologia , Queimaduras/tratamento farmacológico , Nanopartículas Metálicas/química , Prata/química , Sulfadiazina/farmacologia , Cicatrização/efeitos dos fármacos , Administração Tópica , Animais , Antibacterianos/administração & dosagem , Queimaduras/patologia , Queimaduras/fisiopatologia , Composição de Medicamentos/métodos , Quimioterapia Combinada , Emulsões , Escherichia coli/efeitos dos fármacos , Química Verde , Humanos , Masculino , Camundongos , Óleos/química , Tamanho da Partícula , Permeabilidade , Pele/efeitos dos fármacos , Pele/patologia , Pele/fisiopatologia , Staphylococcus aureus/efeitos dos fármacos , Sulfadiazina/administração & dosagem , Tensoativos/química
8.
Proc Natl Acad Sci U S A ; 110(19): E1807-16, 2013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23620513

RESUMO

Apolipoprotein E gene (APOE) alleles may shift the onset of Alzheimer's disease (AD) through apoE protein isoforms changing the probability of amyloid-ß (Aß) accumulation. It has been proposed that differential physical interactions of apoE isoforms with soluble Aß (sAß) in brain fluids influence the metabolism of Aß, providing a mechanism to account for how APOE influences AD risk. In contrast, we provide clear evidence that apoE and sAß interactions occur minimally in solution and in the cerebrospinal fluid of human subjects, producing apoE3 and apoE4 isoforms as assessed by multiple biochemical and analytical techniques. Despite minimal extracellular interactions with sAß in fluid, we find that apoE isoforms regulate the metabolism of sAß by astrocytes and in the interstitial fluid of mice that received apoE infusions during brain Aß microdialysis. We find that a significant portion of apoE and sAß compete for the low-density lipoprotein receptor-related protein 1 (LRP1)-dependent cellular uptake pathway in astrocytes, providing a mechanism to account for apoE's regulation of sAß metabolism despite minimal evidence of direct interactions in extracellular fluids. We propose that apoE influences sAß metabolism not through direct binding to sAß in solution but through its actions with other interacting receptors/transporters and cell surfaces. These results provide an alternative frame work for the mechanistic explanations on how apoE isoforms influence the risk of AD pathogenesis.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Apolipoproteínas E/metabolismo , Regulação da Expressão Gênica , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/genética , Animais , Encéfalo/patologia , Linhagem Celular , Colesterol/metabolismo , Humanos , Camundongos , Camundongos Knockout , Doenças Neurodegenerativas/metabolismo , Ligação Proteica , Isoformas de Proteínas/metabolismo , Fatores de Tempo
9.
Blood ; 119(3): 894-903, 2012 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-22117042

RESUMO

The endothelial ETS transcription factor Erg plays an important role in homeostasis and angiogenesis by regulating many endothelial functions including survival and junction stability. Here we show that Erg regulates endothelial cell (EC) migration. Transcriptome profiling of Erg-deficient ECs identified ∼ 80 genes involved in cell migration as candidate Erg targets, including many regulators of Rho- GTPases. Inhibition of Erg expression in HUVECs resulted in decreased migration in vitro, while Erg overexpression using adenovirus caused increased migration. Live-cell imaging of Erg-deficient HUVECs showed a reduction in lamellipodia, in line with decreased motility. Both actin and tubulin cytoskeletons were disrupted in Erg-deficient ECs, with a dramatic increase in tubulin acetylation. Among the most significant microarray hits was the cytosolic histone deacetylase 6 (HDAC6), a regulator of cell migration. Chromatin immunoprecipitation (ChIP) and transactivation studies demonstrated that Erg regulates HDAC6 expression. Rescue experiments confirmed that HDAC6 mediates the Erg-dependent regulation of tubulin acetylation and actin localization. In vivo, inhibition of Erg expression in angiogenic ECs resulted in decreased HDAC6 expression with increased tubulin acetylation. Thus, we have identified a novel function for the transcription factor Erg in regulating HDAC6 and multiple pathways essential for EC migration and angiogenesis.


Assuntos
Biomarcadores/metabolismo , Movimento Celular , Endotélio Vascular/metabolismo , Regulação da Expressão Gênica , Histona Desacetilases/genética , Neovascularização Fisiológica , Transdução de Sinais , Transativadores/metabolismo , Acetilação , Actinas/metabolismo , Western Blotting , Células Cultivadas , Imunoprecipitação da Cromatina , Endotélio Vascular/citologia , Perfilação da Expressão Gênica , Desacetilase 6 de Histona , Histona Desacetilases/metabolismo , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transativadores/antagonistas & inibidores , Transativadores/genética , Regulador Transcricional ERG , Veias Umbilicais/citologia , Veias Umbilicais/metabolismo
10.
Expert Opin Drug Deliv ; 21(4): 639-662, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38703363

RESUMO

INTRODUCTION: Novel injectables possess applications in both local and systemic therapeutics delivery. The advancement in utilized materials for the construction of complex injectables has tremendously upgraded their safety and efficacy. AREAS COVERED: This review focuses on various strategies to produce novel injectables, including oily dispersions, in situ forming implants, injectable suspensions, microspheres, liposomes, and antibody-drug conjugates. We herein present a detailed description of complex injectable technologies and their related drug formulations permitted for clinical use by the United States Food and Drug Administration (USFDA). The excipients used, their purpose and the challenges faced during manufacturing such formulations have been critically discussed. EXPERT OPINION: Novel injectables can deliver therapeutic agents in a controlled way at the desired site. However, several challenges persist with respect to their genericization. Astronomical costs incurred by innovator companies during product development, complexity of the product itself, supply limitations with respect to raw materials, intricate manufacturing processes, patent evergreening, product life-cycle extensions, relatively few and protracted generic approvals contribute to the exorbitant prices and access crunch. Moreover, regulatory guidance are grossly underdeveloped and significant efforts have to be directed toward development of effective characterization techniques.


Assuntos
Aprovação de Drogas , Sistemas de Liberação de Medicamentos , Injeções , United States Food and Drug Administration , Humanos , Estados Unidos , Desenvolvimento de Medicamentos , Composição de Medicamentos , Excipientes/química , Preparações Farmacêuticas/administração & dosagem , Animais , Química Farmacêutica
11.
Nanomedicine (Lond) ; : 1-16, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39115873

RESUMO

Aim & Objective: This study evaluates the potential of combining paclitaxel (PTX) and bortezomib (BTZ) for breast cancer therapy. Materials & Methods: The nanoformulation was optimized via Box-Behnken Design (BBD), with method validation adhering to US-FDA guidelines. Results: Multiple reaction monitoring transitions for PTX, BTZ and internal standard were m/z 855.80→286.60, 366.80→226.00 and 179.80→110.00, respectively. Elution done on C18 Luna column with 0.1% FA in MeOH:10 mM ammonium acetate. The size of nanoformulation was 133.9 ± 1.97 nm, PDI 0.19 ± 0.01 and zeta potential -19.20 ± 1.36 mV. Pharmacokinetics showed higher Cmax for PTX-BTZ-NE (313.75 ± 10.71 ng/ml PTX, 11.92 ± 0.53 ng/ml BTZ) versus free PTX-BTZ (104 ± 13.06 ng/ml PTX, 1.9 ± 0.08 ng/ml BTZ). Conclusion: Future findings will contribute to the treatment of breast cancer using PTX and BTZ.


[Box: see text].

12.
Cardiovasc Res ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717632

RESUMO

AIMS: Vascular aging is characterized by vessel stiffening, with increased deposition of extracellular matrix (ECM) proteins including collagens. Oxidative DNA damage occurs in vascular aging, but how it regulates ECM proteins and vascular stiffening is unknown. We sought to determine the relationship between oxidative DNA damage and ECM regulatory proteins in vascular aging. METHODS AND RESULTS: We examined oxidative DNA damage, the major base excision repair (BER) enzyme 8-Oxoguanine DNA Glycosylase (Ogg1) and its regulators, multiple physiological markers of aging, and ECM proteomics in mice from 22-72w. Vascular aging was associated with increased oxidative DNA damage, and decreased expression of Ogg1, its active acetylated form, its acetylation regulatory proteins P300 and CBP, and the transcription factor Foxo3a. Vascular stiffness was examined in vivo in control, Ogg1-/-, or mice with vascular smooth muscle cell-specific expression of Ogg1+ (Ogg1) or an inactive mutation (Ogg1KR). Ogg1-/- and Ogg1KR mice showed reduced arterial compliance and distensibility, and increased stiffness and pulse pressure, whereas Ogg1 expression normalised all parameters to 72w. ECM proteomics identified major changes in collagens with aging, and downregulation of the ECM regulatory proteins Protein 6-lysyl oxidase (LOX) and WNT1-inducible-signaling pathway protein 2 (WISP2). Ogg1 overexpression upregulated LOX and WISP2 both in vitro and in vivo, and downregulated Transforming growth factor ß1 (TGFb1) and Collagen 4α1 in vivo compared with Ogg1KR. Foxo3a activation induced Lox, while Wnt3 induction of Wisp2 also upregulated LOX and Foxo3a, and downregulated TGFß1 and fibronectin 1. In humans, 8-oxo-G increased with vascular stiffness, while active OGG1 reduced with both age and stiffness. CONCLUSIONS: Vascular aging is associated with oxidative DNA damage, downregulation of major BER proteins, and changes in multiple ECM structural and regulatory proteins. Ogg1 protects against vascular aging, associated with changes in ECM regulatory proteins including LOX and WISP2.

14.
PLoS Genet ; 6(9): e1001101, 2010 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-20862329

RESUMO

Alzheimer's Disease (AD) is a complex and multifactorial disease. While large genome-wide association studies have had some success in identifying novel genetic risk factors for AD, case-control studies are less likely to uncover genetic factors that influence progression of disease. An alternative approach to identifying genetic risk for AD is the use of quantitative traits or endophenotypes. The use of endophenotypes has proven to be an effective strategy, implicating genetic risk factors in several diseases, including anemia, osteoporosis and heart disease. In this study we identify a genetic factor associated with the rate of decline in AD patients and present a methodology for identification of other such factors. We have used an established biomarker for AD, cerebrospinal fluid (CSF) tau phosphorylated at threonine 181 (ptau(181)) levels as an endophenotype for AD, identifying a SNP, rs1868402, in the gene encoding the regulatory sub-unit of protein phosphatase B, associated with CSF ptau(181) levels in two independent CSF series (P(combined) = 1.17 x 10(-05)). We show no association of rs1868402 with risk for AD or age at onset, but detected a very significant association with rate of progression of disease that is consistent in two independent series (P(combined) = 1.17 x 10(-05)). Our analyses suggest that genetic variants associated with CSF ptau(181) levels may have a greater impact on rate of progression, while genetic variants such as APOE4, that are associated with CSF Aß(42) levels influence risk and onset but not the rate of progression. Our results also suggest that drugs that inhibit or decrease tau phosphorylation may slow cognitive decline in individuals with very mild dementia or delay the appearance of memory problems in elderly individuals with low CSF Aß(42) levels. Finally, we believe genome-wide association studies of CSF tau/ptau(181) levels should identify novel genetic variants which will likely influence rate of progression of AD.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/genética , Progressão da Doença , Predisposição Genética para Doença , Fosfoproteínas/líquido cefalorraquidiano , Polimorfismo de Nucleotídeo Único/genética , Proteínas tau/líquido cefalorraquidiano , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Peptídeos beta-Amiloides/metabolismo , Biomarcadores/metabolismo , Calcineurina/genética , Calcineurina/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/líquido cefalorraquidiano , Fragmentos de Peptídeos/metabolismo , Fosfoproteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Fatores de Risco , Análise de Sobrevida , Washington/epidemiologia , Proteínas tau/metabolismo
15.
bioRxiv ; 2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36798267

RESUMO

Background: During infectious diseases, pro-inflammatory cytokines transiently destabilize interactions between adjacent vascular endothelial cells (ECs) to facilitate the passage of immune molecules and cells into tissues. However, in the lung the resulting vascular hyperpermeability can lead to organ dysfunction. Previous work identified the transcription factor ERG as a master regulator of endothelial homeostasis. Here we investigate whether the sensitivity of pulmonary blood vessels to cytokine-induced destabilization is due to organotypic mechanisms affecting the ability of endothelial ERG to protect lung ECs from inflammatory injury. Methods: Cytokine-dependent ubiquitination and proteasomal degradation of ERG was analyzed in cultured Human Umbilical Vein ECs (HUVECs). Systemic administration of TNFα or the bacterial cell wall component lipopolysaccharide (LPS) was used to cause a widespread inflammatory challenge in mice; ERG protein levels were assessed by immunoprecipitation, immunoblot, and immunofluorescence. Murine Erg deletion was genetically induced in ECs ( Erg fl/fl ;Cdh5(PAC)Cre ERT2 ), and multiple organs were analyzed by histology, immunostaining, and electron microscopy. Results: In vitro, TNFα promoted the ubiquitination and degradation of ERG in HUVECs, which was blocked by the proteasomal inhibitor MG132. In vivo, systemic administration of TNFα or LPS resulted in a rapid and substantial degradation of ERG within lung ECs, but not ECs of the retina, heart, liver, or kidney. Pulmonary ERG was also downregulated in a murine model of influenza infection. Erg fl/fl ;Cdh5(PAC)-Cre ERT2 mice spontaneously recapitulated aspects of inflammatory challenges, including lung-predominant vascular hyperpermeability, immune cell recruitment, and fibrosis. These phenotypes were associated with a lung-specific decrease in the expression of Tek , a gene target of ERG previously implicated in maintaining pulmonary vascular stability during inflammation. Conclusions: Collectively, our data highlight a unique role for ERG in pulmonary vascular function. We propose that cytokine-induced ERG degradation and subsequent transcriptional changes in lung ECs play critical roles in the destabilization of pulmonary blood vessels during infectious diseases.

16.
Insights Imaging ; 14(1): 170, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37840055

RESUMO

BACKGROUND: The Myeloma Response Assessment and Diagnosis System (MY-RADS) guidelines establish a standardised acquisition and analysis pipeline for whole-body MRI (WB-MRI) in patients with myeloma. This is the first study to assess image quality in a multi-centre prospective trial using MY-RADS. METHODS: The cohort consisted of 121 examinations acquired across ten sites with a range of prior WB-MRI experience, three scanner manufacturers and two field strengths. Image quality was evaluated qualitatively by a radiologist and quantitatively using a semi-automated pipeline to quantify common artefacts and image quality issues. The intra- and inter-rater repeatability of qualitative and quantitative scoring was also assessed. RESULTS: Qualitative radiological scoring found that the image quality was generally good, with 94% of examinations rated as good or excellent and only one examination rated as non-diagnostic. There was a significant correlation between radiological and quantitative scoring for most measures, and intra- and inter-rater repeatability were generally good. When the quality of an overall examination was low, this was often due to low quality diffusion-weighted imaging (DWI), where signal to noise ratio (SNR), anterior thoracic signal loss and brain geometric distortion were found as significant predictors of examination quality. CONCLUSIONS: It is possible to successfully deliver a multi-centre WB-MRI study using the MY-RADS protocol involving scanners with a range of manufacturers, models and field strengths. Quantitative measures of image quality were developed and shown to be significantly correlated with radiological assessment. The SNR of DW images was identified as a significant factor affecting overall examination quality. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03188172 , Registered on 15 June 2017. CRITICAL RELEVANCE STATEMENT: Good overall image quality, assessed both qualitatively and quantitatively, can be achieved in a multi-centre whole-body MRI study using the MY-RADS guidelines. KEY POINTS: • A prospective multi-centre WB-MRI study using MY-RADS can be successfully delivered. • Quantitative image quality metrics were developed and correlated with radiological assessment. • SNR in DWI was identified as a significant predictor of quality, allowing for rapid quality adjustment.

17.
Alzheimer Dis Assoc Disord ; 26(4): 314-21, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22156755

RESUMO

OBJECTIVE: Biomarkers are needed to improve the sensitivity and accuracy of diagnosis, and also prognosis, in individuals with early Alzheimer disease (AD). Measures of brain structure and disease-related proteins in the cerebrospinal fluid (CSF) have been proposed as biomarkers, yet relatively little is known about the relationships between such measures. The present study was conducted to assess the relationship between CSF Aß and tau protein levels and longitudinal measures of hippocampal structure in individuals with and without very mild dementia of the Alzheimer type. DESIGN: A single CSF sample and longitudinal magnetic resonance scans were collected. The CSF samples were assayed for tau, phosphorylated tau181 (p-tau181), Aß1-42, and Aß1-40 using an enzyme-linked immunosorbent assay. Large-deformation diffeomorphic metric mapping was used to generate hippocampal surfaces, and a composite hippocampal surface (previously constructed from 86 healthy participants) was used as a structural reference. PATIENTS OR OTHER PARTICIPANTS: Thirteen participants with very mild AD (Clinical Dementia Rating, CDR 0.5) and 11 cognitively normal participants (CDR 0). INTERVENTION: None. MAIN OUTCOME MEASURES: Initial and rate-of-change measures of total hippocampal volume and displacement of the hippocampal surface within zones overlying the CA1, subiculum, and CA2-4+DG cellular subfields, and their correlations with initial CSF measures. RESULTS: Lower CSF Αß1-42 levels and higher tau/Αß1-42 and p-tau181/Αß1-42 ratios were strongly correlated with decreases in hippocampal volume and measures of progressive inward deformations of the CA1 subfield in participants with early AD, but not in cognitively normal participants. CONCLUSIONS: Despite the small sample size, we found that Αß1-42 related and tau-related CSF measures were associated with hippocampal degeneration in individuals with clinically diagnosed early AD and may reflect an association with a common underlying disease mechanism.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Biomarcadores/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano , Idoso , Ensaio de Imunoadsorção Enzimática , Feminino , Hipocampo/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Degeneração Neural/patologia
18.
Cardiovasc Res ; 118(7): 1713-1727, 2022 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34142149

RESUMO

AIMS: Traditional markers of cell senescence including p16, Lamin B1, and senescence-associated beta galactosidase (SAßG) suggest very high frequencies of senescent cells in atherosclerosis, while their removal via 'senolysis' has been reported to reduce atherogenesis. However, selective killing of a variety of different cell types can exacerbate atherosclerosis. We therefore examined the specificity of senescence markers in vascular smooth muscle cells (VSMCs) and the effects of genetic or pharmacological senolysis in atherosclerosis. METHODS AND RESULTS: We examined traditional senescence markers in human and mouse VSMCs in vitro, and in mouse atherosclerosis. p16 and SAßG increased and Lamin B1 decreased in replicative senescence and stress-induced premature senescence (SIPS) of cultured human VSMCs. In contrast, mouse VSMCs undergoing SIPS showed only modest p16 up-regulation, and proliferating mouse monocyte/macrophages also expressed p16 and SAßG. Single cell RNA-sequencing (scRNA-seq) of lineage-traced mice showed increased p16 expression in VSMC-derived cells in plaques vs. normal arteries, but p16 localized to Stem cell antigen-1 (Sca1)+ or macrophage-like populations. Activation of a p16-driven suicide gene to remove p16+ vessel wall- and/or bone marrow-derived cells increased apoptotic cells, but also induced inflammation and did not change plaque size or composition. In contrast, the senolytic ABT-263 selectively reduced senescent VSMCs in culture, and markedly reduced atherogenesis. However, ABT-263 did not reduce senescence markers in vivo, and significantly reduced monocyte and platelet counts and interleukin 6 as a marker of systemic inflammation. CONCLUSIONS: We show that genetic and pharmacological senolysis have variable effects on atherosclerosis, and may promote inflammation and non-specific effects respectively. In addition, traditional markers of cell senescence such as p16 have significant limitations to identify and remove senescent cells in atherosclerosis, suggesting that senescence studies in atherosclerosis and new senolytic drugs require more specific and lineage-restricted markers before ascribing their effects entirely to senolysis.


Assuntos
Aterosclerose , Placa Aterosclerótica , Animais , Aterosclerose/genética , Aterosclerose/metabolismo , Biomarcadores/metabolismo , Células Cultivadas , Senescência Celular , Humanos , Inflamação/metabolismo , Camundongos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Placa Aterosclerótica/metabolismo , Senoterapia
19.
Cancers (Basel) ; 15(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36612090

RESUMO

Novel biomarkers for tumour burden and bone disease are required to guide clinical management of plasma cell dyscrasias. Recently, bone turnover markers (BTMs) and Diffusion-Weighted Magnetic Resonance Imaging (DW-MRI) have been explored, although their role in the prospective assessment of multiple myeloma (MM) and monoclonal gammopathy of undetermined significance (MGUS) is unclear. Here, we conducted a pilot observational cohort feasibility study combining serum BTMs and DW-MRI in addition to standard clinical assessment. Fifty-five patients were recruited (14 MGUS, 15 smouldering MM, 14 new MM and 12 relapsed MM) and had DW-MRI and serum biomarkers (P1NP, CTX-1, ALP, DKK1, sclerostin, RANKL:OPG and BCMA) measured at baseline and 6-month follow-up. Serum sclerostin positively correlated with bone mineral density (r = 0.40-0.54). At baseline, serum BCMA correlated with serum paraprotein (r = 0.42) and serum DKK1 correlated with serum free light chains (r = 0.67); the longitudinal change in both biomarkers differed between International Myeloma Working Group (IMWG)-defined responders and non-responders. Myeloma Response Assessment and Diagnosis System (MY-RADS) scoring of serial DW-MRI correlated with conventional IMWG response criteria for measuring longitudinal changes in tumour burden. Overall, our pilot study suggests candidate radiological and serum biomarkers of tumour burden and bone loss in MM/MGUS, which warrant further exploration in larger cohorts to validate the findings and to better understand their clinical utility.

20.
Insights Imaging ; 13(1): 123, 2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35900614

RESUMO

BACKGROUND: Whole-body (WB) MRI, which includes diffusion-weighted imaging (DWI) and T1-w Dixon, permits sensitive detection of marrow disease in addition to qualitative and quantitative measurements of disease and response to treatment of bone marrow. We report on the first study to embed standardised WB-MRI within a prospective, multi-centre myeloma clinical trial (IMAGIMM trial, sub-study of OPTIMUM/MUKnine) to explore the use of WB-MRI to detect minimal residual disease after treatment. METHODS: The standardised MY-RADS WB-MRI protocol was set up on a local 1.5 T scanner. An imaging manual describing the MR protocol, quality assurance/control procedures and data transfer was produced and provided to sites. For non-identical scanners (different vendor or magnet strength), site visits from our physics team were organised to support protocol optimisation. The site qualification process included review of phantom and volunteer data acquired at each site and a teleconference to brief the multidisciplinary team. Image quality of initial patients at each site was assessed. RESULTS: WB-MRI was successfully set up at 12 UK sites involving 3 vendor systems and two field strengths. Four main protocols (1.5 T Siemens, 3 T Siemens, 1.5 T Philips and 3 T GE scanners) were generated. Scanner limitations (hardware and software) and scanning time constraint required protocol modifications for 4 sites. Nevertheless, shared methodology and imaging protocols enabled other centres to obtain images suitable for qualitative and quantitative analysis. CONCLUSIONS: Standardised WB-MRI protocols can be implemented and supported in prospective multi-centre clinical trials. Trial registration NCT03188172 clinicaltrials.gov; registration date 15th June 2017 https://clinicaltrials.gov/ct2/show/study/NCT03188172.

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