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1.
Toxicol Sci ; 191(2): 400-413, 2023 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-36515490

RESUMEN

Administration of a novel and selective small molecule integrin αvß6 inhibitor, MORF-627, to young cynomolgus monkeys for 28 days resulted in the rapid induction of epithelial proliferative changes in the urinary bladder of 2 animals, in the absence of test agent genotoxicity. Microscopic findings included suburothelial infiltration by irregular nests and/or trabeculae of epithelial cells, variable cytologic atypia, and high mitotic rate, without invasion into the tunica muscularis. Morphologic features and patterns of tumor growth were consistent with a diagnosis of early-stage invasive urothelial carcinoma. Ki67 immunohistochemistry demonstrated diffusely increased epithelial proliferation in the urinary bladder of several monkeys, including those with tumors, and αvß6 was expressed in some epithelial tissues, including urinary bladder, in monkeys and humans. Spontaneous urothelial carcinomas are extremely unusual in young healthy monkeys, suggesting a direct link of the finding to the test agent. Inhibition of integrin αvß6 is intended to locally and selectively block transforming growth factor beta (TGF-ß) signaling, which is implicated in epithelial proliferative disorders. Subsequent in vitro studies using a panel of integrin αvß6 inhibitors in human bladder epithelial cells replicated the increased urothelial proliferation observed in monkeys and was reversed through exogenous application of TGF-ß. Moreover, analysis of in vivo models of liver and lung fibrosis revealed evidence of epithelial hyperplasia and cell cycle dysregulation in mice treated with integrin αvß6 or TGF-ß receptor I inhibitors. The cumulative evidence suggests a direct link between integrin αvß6 inhibition and decreased TGF-ß signaling in the local bladder environment, with implications for epithelial proliferation and carcinogenesis.


Asunto(s)
Carcinoma de Células Transicionales , Integrinas , Neoplasias de la Vejiga Urinaria , Animales , Humanos , Ratones , Carcinoma de Células Transicionales/inducido químicamente , Integrinas/antagonistas & inhibidores , Integrinas/metabolismo , Macaca fascicularis , Factor de Crecimiento Transformador beta/metabolismo , Neoplasias de la Vejiga Urinaria/inducido químicamente
2.
Compr Rev Food Sci Food Saf ; 20(3): 2596-2625, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33682364

RESUMEN

Per- and polyfluoroalkyl substances (PFAS) have been used in food contact paper and paperboard for decades due to their unique ability to provide both moisture and oil/grease resistance. Once thought to be innocuous, it is now clear that long chain PFAS bioaccumulate and are linked to reproductive and developmental abnormalities, suppressed immune response, and tumor formation. Second-generation PFAS have shorter biological half-lives but concerns about health risks from chronic exposure underscore the need for safe substitutes. Waxes and polymer film laminates of polyethylene, poly(ethylene-co-vinyl alcohol), and polyethylene terephthalate are commonly used alternatives. However, such laminates are neither compostable nor recyclable. Lamination with biodegradable polymers, including polyesters, such as polylactic acid (PLA), polybutylene adipate terephthalate, polybutylene succinate, and polyhydroxyalkanoates, are of growing research and commercial interest. PLA films are perhaps the most viable alternative, but performance and compostability are suboptimal. Surface sizings and coatings of starches, chitosan, alginates, micro- and nanofibrilated cellulose, and gelatins provide adequate oil barrier properties but have poor moisture resistance without chemical modification. Plant proteins, including soy, wheat gluten, and corn zein, have been tested as paper coatings with soy being the most commercially important. Internal sizing agents, such as alkyl ketene dimers, alkenyl succinic anhydride, and rosin, improve moisture resistance but are poor oil/grease barriers. The difficulty in finding a viable replacement for PFAS chemicals that is cost-effective, fully biodegradable, and environmentally sound underscores the need for more research to improve barrier properties and process economics in food packaging products.


Asunto(s)
Quitosano , Polihidroxialcanoatos , Celulosa , Embalaje de Alimentos , Polietileno
3.
J Invest Dermatol ; 140(5): 1015-1025.e4, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31715177

RESUMEN

Many psoriasis patients treated with biologics do not achieve total skin clearance. These patients possess residual plaques despite ongoing biologic treatment. To elucidate mechanisms of plaque persistence despite overall good drug response, we studied 50 subjects: psoriasis patients with residual plaques treated with one of three different biologics, untreated patients, and healthy controls. Skin biopsies from all subjects were characterized using three methods: mRNA expression, histology, and FACS of hematopoietic skin cells. Although all three methods provided evidence of drug effect, gene expression analysis revealed the persistence of key psoriasis pathways in treated plaques, including granulocyte adhesion and diapedesis, T helper type17 activation pathway, and interferon signaling with no novel pathways emerging. Focal decreases in parakeratosis and keratinocyte proliferation and differential reduction in IL-17 producing CD103- T cells, but no change in CD103+ tissue-resident memory T cells were observed. Of note, antitumor necrosis factor increased the interferon signaling pathway already present. Interestingly mast cells were the dominant source of IL-22 in all psoriasis subjects. These data suggest that while subtle differences can be observed in drug-treated plaques, underlying biologic mechanisms are similar to those present in untreated psoriatic lesions.


Asunto(s)
Productos Biológicos/uso terapéutico , Inflamación/tratamiento farmacológico , Mastocitos/inmunología , Psoriasis/terapia , Células Th17/inmunología , Adulto , Células Cultivadas , Enfermedad Crónica , Progresión de la Enfermedad , Femenino , Humanos , Memoria Inmunológica , Inflamación/inmunología , Interleucinas/metabolismo , Masculino , Persona de Mediana Edad , Paraqueratosis , Fenotipo , Psoriasis/inmunología , Adulto Joven , Interleucina-22
4.
Am J Nephrol ; 44(5): 339-353, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27736813

RESUMEN

BACKGROUND: Obese ZSF-1 rats display many features of human type II diabetes including nephropathy (DN). The study aimed to further understand the relevance of this model to DN, for which glomerular filtration rate (GFR), renal fibrosis and several urinary/tissue biomarkers was followed over 24 weeks in ZSF-1 rats. METHODS: Intact/sham or uninephrectomized male and female ZSF-1 rats were studied. GFR was measured by transdermal clearance of fluorescein isothiocyanate-sinistrin. Urine was collected every 2-4 weeks for biomarker analysis. Renal tissue was examined histologically for fibrosis and for levels of inflammatory and fibrotic genes. RESULTS: Male obese ZSF-1 rats demonstrated metabolic syndrome and proteinuria. Female counterparts were hyperlipidemic with delayed proteinuria, but were not hyperglycemic. Kidney hyperfiltration was observed in male obese rats in weeks 2-4 after surgery, and subsequently declined to levels significantly lower than controls. Tubulointerstitial/glomerular fibrosis in male obese rats was significantly elevated by week 12 post surgery and continued to expand in the ensuing weeks, particularly in uninephrectomized rats. Female rats had less severe fibrosis. Except for epidermal growth factor which decreased, the levels of several key inflammatory, injury and fibrotic factors were elevated in both tissue (mRNA) and urine (protein) of male obese rats. CONCLUSION: Male obese ZSF-1 rats represent an important DN model, manifesting key pathophysiological features including metabolic syndrome, proteinuria, progressive tubular and glomerular fibrosis, and transient hyperfiltration followed by progressive decline in renal function. Uninephrectomy significantly accelerated disease progression. Females were less severe in disease manifestation. Several urinary and tissue biomarkers were identified in the male obese rats that tracked with disease progression.


Asunto(s)
Nefropatías Diabéticas/fisiopatología , Modelos Animales de Enfermedad , Tasa de Filtración Glomerular , Riñón/patología , Animales , Biomarcadores/orina , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Nefropatías Diabéticas/etiología , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Femenino , Fibrosis , Perfilación de la Expresión Génica , Masculino , Nefroesclerosis/etiología , Nefroesclerosis/patología , Ratas
5.
Eur J Pharmacol ; 788: 1-11, 2016 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-27288879

RESUMEN

Adenosine (ADO) is an important regulatory purine nucleoside that accumulates at sites of inflammation and tissue injury including in diseases associated with renal pathology. Endogenous levels of ADO may be increased by inhibiting the ADO-metabolizing enzyme, ADO kinase (AK). AK inhibitors have demonstrated protection in rodent models of diabetic nephropathy. To further investigate AK inhibition as a potential mechanism for renal protection, A-306989, a potent non-nucleoside AK inhibitor, was examined in both in vitro and in vivo assays of renal injury. A-306989 prevented podocyte damage (disruption of actin cytoskeleton) and increased podocyte survival following puromycin aminonucleoside (PAN) application in both mouse and human conditionally immortalized podocytes. Prophylactic oral administration of A-306989 (1.5, 5 and 15mg/kg) reduced proteinuria in a dose-dependent manner and repressed pro-inflammatory/fibrotic gene up-regulation; A-306989 was also efficacious when administered two days following the PAN-insult. A-306989 (10 and 30mg/kg) also significantly reduced proteinuria and macrophage infiltration in a rat model of glomerulonephritis. Finally, A-306989 (15 and 50mg/kg) reduced the expression levels of pro-inflammatory/fibrotic genes, and reduced macrophage infiltration (50mg/kg), but did not affect the deposition of interstitial collagen in fibrotic kidneys from mice with unilateral ureter obstruction. A-306989 also had beneficial actions on "quality of life" measures including improving body weight loss. Thus, these data indicate that enhancement of endogenous ADO levels by A-306989 can positively modulate renal pathology and mimic some of the previously reported beneficial actions of ADO A2A receptor agonists.


Asunto(s)
Adenosina Quinasa/antagonistas & inhibidores , Membrana Basal/diagnóstico por imagen , Citoprotección/efectos de los fármacos , Riñón/citología , Riñón/lesiones , Podocitos/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Animales , Fibrosis , Riñón/efectos de los fármacos , Riñón/patología , Masculino , Ratones , Podocitos/citología , Podocitos/metabolismo , Puromicina Aminonucleósido/toxicidad , Ratas
6.
Dement Geriatr Cogn Disord ; 31(6): 443-50, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21778725

RESUMEN

BACKGROUND/AIMS: Instrumental activities of daily living (IADL) impairment in Alzheimer's disease has been associated with global amyloid deposition in postmortem studies. We sought to determine whether IADL impairment is associated with increased cortical Pittsburgh Compound B (PiB) retention. METHODS: Fifty-five subjects (19 normal older controls, NC, and 36 with mild cognitive impairment, MCI) underwent clinical assessments and dynamic PiB positron emission tomography imaging. RESULTS: A linear multiple regression model showed that greater IADL impairment was associated with greater global PiB retention in all subjects (R(2) = 0.40; unstandardized partial regression coefficient, ß = 5.8; p = 0.0002) and in MCI subjects only (R(2) = 0.28; ß = 6.1; p = 0.003), but not in NC subjects only. CONCLUSION: These results suggest that daily functional impairment is related to greater amyloid burden in MCI.


Asunto(s)
Actividades Cotidianas/psicología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/psicología , Amiloide/metabolismo , Anciano , Anciano de 80 o más Años , Amiloidosis/diagnóstico por imagen , Amiloidosis/metabolismo , Compuestos de Anilina/metabolismo , Carga Corporal (Radioterapia) , Interpretación Estadística de Datos , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Tomografía de Emisión de Positrones , Análisis de Regresión , Encuestas y Cuestionarios , Lóbulo Temporal/fisiología , Tiazoles/metabolismo
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