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1.
Case Rep Nephrol ; 2024: 9218637, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38716184

RESUMO

Thrombotic microangiopathy (TMA) reflects a syndrome of endothelial injury characterised by microangiopathic haemolytic anaemia (nonimmune), thrombocytopenia, and often end-organ dysfunction. TMA disorders are well-recognised in kidney transplant recipients, often due to an underlying genetic predisposition related to complement dysregulation, or de novo due to infection, immunosuppression toxicity, or antibody-mediated rejection. In pregnancy, TMA disorders are most commonly due to severe pre-eclampsia or HELLP, but may also be due to thrombotic thrombocytopenic purpura (TTP) or complement-mediated (atypical) haemolytic uremic syndrome (aHUS). Complement dysregulation is being recognised as playing a role in the development of preeclampsia and HELLP syndrome in addition to aHUS. Due to overlapping clinical and laboratory features, diagnosis can be difficult and delays in treatment can be life-threatening for both mother and fetus. This report describes a 32 year-old female who had two successive wanted pregnancies. The first pregnancy was terminated at 22 weeks gestation due to presumed severe preeclampsia and fetal growth restriction in the context of known chronic kidney failure due to reflux nephropathy. A living-related kidney transplant was performed to improve the chances of pregnancy resulting in a live birth. A subsequent pregnancy was complicated by progressive kidney impairment and hypertension at 22 weeks gestation. Kidney biopsy showed TMA, but the etiology was unclear. This report highlights the diagnostic dilemma of TMA in a pregnant kidney transplant recipient and a role for the anti-C5 terminal complement blockade monoclonal antibody eculizumab, in pregnancy-associated TMA, especially at a peri-viable gestation.

2.
J Cachexia Sarcopenia Muscle ; 14(1): 126-141, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36351875

RESUMO

BACKGROUND: Muscle wasting is a common complication of chronic kidney disease (CKD) that is associated with higher mortality. Although the mechanisms of myofibre loss in CKD has been widely studied, the contribution of muscle precursor cell (MPC) senescence remains poorly understood. Senescent MPCs no longer proliferate and can produce proinflammatory factors or cytokines. In this study, we tested the hypothesis that the senescence associated secretory phenotype (SASP) of MPCs contributes to CKD-induced muscle atrophy and weakness. METHODS: CKD was induced in mice by 5/6th nephrectomy. Kidney function, muscle size, and function were measured, and markers of atrophy, inflammation, and senescence were evaluated using immunohistochemistry, immunoblots, or qPCR. To study the impact of senescence, a senolytics cocktail of dasatinib + quercetin (D&Q) was given orally to mice for 8 weeks. To investigate CKD-induced senescence at the cellular level, primary MPCs were incubated with serum from CKD or control subjects. The roles of specific proteins in MPC senescence were studied using adenoviral transduction, siRNA, and plasmid transfection. RESULTS: In the hindlimb muscles of CKD mice, (i) the senescence biomarker SA-ß-gal was sharply increased (~30-fold); (ii) the DNA damage response marker γ-H2AX was increased 1.9-fold; and (iii) the senescence pathway markers p21 and p16INK4a were increased 1.99-fold and 2.82-fold, respectively (all values, P < 0.05), whereas p53 was unchanged. γ-H2AX, p21, and p16INK4A were negatively correlated at P < 0.05 with gastrocnemius weight, suggesting a causal relationship with muscle atrophy. Administration of the senolytics cocktail to CKD mice for 8 weeks eliminated the disease-related elevation of p21, p16INK4a , and γ-H2AX, abolished positive SA-ß-gal, and depressed the high levels of the SASP cytokines, TNF-α, IL-6, IL-1ß, and IFN (all values, P < 0.05). Skeletal muscle weight, myofibre cross-sectional area, and grip function were improved in CKD mice receiving D&Q. Markers of protein degradation, inflammation, and MPCs dysfunction were also attenuated by D&Q treatment compared with the vehicle treatment in 5/6th nephrectomy mice (all values, P < 0.05). Uraemic serum induced senescence in cultured MPCs. Overexpression of FoxO1a in MPCs increased the number of p21+ senescent cells, and p21 siRNA prevented uraemic serum-induced senescence (P < 0.05). CONCLUSIONS: Senescent MPCs are likely to contribute to the development of muscle wasting during CKD by producing inflammatory cytokines. Limiting senescence with senolytics ameliorated muscle wasting and improved muscle strength in vivo and restored cultured MPC functions. These results suggest potential new therapeutic targets to improve muscle health and function in CKD.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina , Insuficiência Renal Crônica , Animais , Camundongos , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Senoterapia , Insuficiência Renal Crônica/complicações , Citocinas/metabolismo , Atrofia Muscular/etiologia , Músculos/metabolismo , RNA Interferente Pequeno
3.
J Ren Nutr ; 33(6S): S88-S92, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36183901

RESUMO

OBJECTIVE: This perspective reviews the seminal clinical and experimental observations that led to today's current mechanistic model of muscle protein loss (wasting) in patients with chronic kidney disease (CKD). RESULTS AND CONCLUSION: Early International Society of Renal Nutrition and Metabolism (ISRNM) meetings facilitated discussions and hypotheses about the causes of muscle wasting in CKD. It became widely recognized that wasting is common and correlated with increased risks of mortality and morbidity. Although anorexia and dietary restrictions contribute to muscle loss, several features of CKD-associated wasting cannot be explained by malnutrition alone. The protein catabolism-inducing actions of metabolic acidosis, inflammation, insulin resistance, endocrine disorders and uremic toxins were progressively identified. Continued research to understand the interactions of inflammation, anabolic resistance, mitochondrial dysfunction, exercise, and nutrition on muscle protein turnover in patients with CKD will hopefully accelerate discoveries and treatments to ameliorate muscle wasting as well as the progression of CKD.


Assuntos
Insuficiência Renal Crônica , Humanos , Atrofia Muscular , Caquexia , Proteínas Musculares , Inflamação/complicações
4.
Integr Org Biol ; 3(1): obab014, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34377941

RESUMO

Whether distantly related organisms evolve similar strategies to meet the demands of a shared ecological niche depends on their evolutionary history and the nature of form-function relationships. In fishes, the visual identification and consumption of microscopic zooplankters, selective zooplanktivory, is a distinct type of foraging often associated with a suite of morphological specializations. Previous work has identified inconsistencies in the trajectory and magnitude of morphological change following transitions to selective zooplanktivory, alluding to the diversity and importance of ancestral effects. Here we investigate whether transitions to selective zooplanktivory have influenced the morphological evolution of marine butterflyfishes (family Chaetodontidae), a group of small-prey specialists well known for several types of high-precision benthivory. Using Bayesian ancestral state estimation, we inferred the recent evolution of zooplanktivory among benthivorous ancestors that hunted small invertebrates and browsed by picking or scraping coral polyps. Traits related to the capture of prey appear to be functionally versatile, with little morphological distinction between species with benthivorous and planktivorous foraging modes. In contrast, multiple traits related to prey detection or swimming performance are evolving toward novel, zooplanktivore-specific optima. Despite a relatively short evolutionary history, general morphological indistinctiveness, and evidence of constraint on the evolution of body size, convergent evolution has closed a near significant amount of the morphological distance between zooplanktivorous species. Overall, our findings describe the extent to which the functional demands associated with selective zooplanktivory have led to generalizable morphological features among butterflyfishes and highlight the importance of ancestral effects in shaping patterns of morphological convergence.


A evolução de estratégias similares para suprir as demandas de nichos ecológicos compartilhados em organismos pouco relacionados, depende da sua história evolutiva e da natureza das relações entre forma e função. Em peixes, a identificação visual e o consumo de zooplanctôn microscópico, a zooplanctivoria seletiva, é um tipo distinto de forrageamento frequentemente associado a um conjunto de especializações morfológicas. Estudos anteriores identificaram inconsistências na trajetória e magnitude das mudanças morfológicas que surgem a partir das transições para a zooplanctivoria seletiva, fazendo alusão à diversidade e importância dos efeitos ancestrais. Aqui investigamos se transições para a zooplanctivoria seletiva influenciaram a evolução morfológica dos peixes-borboleta marinhos (família Chaetodontidae), um grupo especialista em presas pequenas conhecido pelos muitos tipos de bentivoria de alta precisão. Utilizando uma estimativa ancestral bayesiana, inferimos a evolução recente da zooplanctivoria dentre os ancestrais bentívoros que caçavam pequenos invertebrados e alimentavam-se de pólipos de coral. Características relacionadas a captura de presa parecem ser funcionalmente versáteis com pouca distinção entre as espécies com modo de forrageamento bentívoro e planctívoro. Em contraste, várias características relacionadas a detecção da presa ou capacidade natatória estão evoluindo em direção a um novo ótimo, específico para a zooplanctivoria. Apesar da história evolutiva relativamente recente, uma morfologia geral comum, e evidência de uma restrição na evolução do tamanho corporal, a evolução convergente reduziu significativamente a distância morfológica entre as espécies zooplanctívoras. No geral, nossos resultados descrevem até que ponto as demandas funcionais associadas à zooplanctivoria seletiva levaram a características morfológicas generalizadas nos peixes-borboleta e destacam a importância dos efeitos ancestrais em moldar os padrões de convergência morfológica.


El hecho de que organismos con parentesco lejano evolucionen estrategias similares para satisfacer las demandas de un nicho ecológico compartido depende de su historia evolutiva y de la naturaleza de la relación forma-función. En peces, la identificación visual y el consumo de plancton microscópico, la zooplanctivoría selectiva, es un tipo específico de alimentación usualmente asociado a un conjunto de especializaciones morfológicas. Estudios previos han identificado inconsistencias en la trayectoria y magnitud de cambios morfológicos tras transiciones hacia zooplanctivoría selectiva, aludiendo a la diversidad e importancia de efectos ancestrales. Aquí investigamos si las transiciones a zooplanctivoría selectiva han influido en la evolución morfológica de los peces mariposa marinos (familia Chaetodontidae), un grupo especializado en presas pequeñas conocido por varios tipos de alimentación de alta precisión en el bentos. Usando una estimación de estado ancestral Bayesiana, inferimos la evolución reciente de la zooplanctivoría entre ancestros bentívoros que cazaron pequeños invertebrados y se alimentaron de pólipos de coral. Los rasgos relacionados con la captura de presas parecen ser versátiles funcionalmente con escasa distinción morfológica entre especies con modos de alimentación bentívoros y planctívoros. En cambio, múltiples rasgos relacionados con la detección de presas o con la capacidad natatoria están evolucionando hacia un nuevo óptimo específico para zooplanctivoría. A pesar de una historia evolutiva relativamente corta, una morfología general común, y evidencia de restricción en la evolución del tamaño de los peces, una evolución convergente ha reducido la distancia morfológica entre especies zooplanctívoras de forma casi significativa. En conclusión, nuestros hallazgos describen hasta qué punto las demandas funcionales asociadas con la zooplanctivoría selectiva han desembocado en rasgos morfológicos generalizados en peces mariposa y destacan la importancia de los efectos ancestrales en la creación de patrones de morfología convergente.

5.
J Am Board Fam Med ; 33(6): 894-902, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33219068

RESUMO

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of death among breast cancer (BC) survivors. BC survivors are at increased risk of CVD due to a higher prevalence of risk factors. Current data are limited on the cardiovascular screening practices and lipid management in this population in primary care settings. METHODS: A retrospective case control study was performed with 105 BC survivors and 210 matched controls (based on age and medical comorbidities of diabetes, hypertension, and hyperlipidemia). BC survivors were established with primary care practices within a large academic institution and had completed primary cancer treatment. Data on screening for CVD and lipid management were collected via a retrospective chart review. RESULTS: The average BC survivor was 63 years old, with 9 years since diagnosis. Compared with matched controls, BC survivors had more cholesterol screening (88% vs 70%, P < .001) and active statin prescriptions (63% vs 40%, P < .05) if indicated by the Atherosclerotic Cardiovascular Disease Calculator. There were no differences in CVD screening in White and African American BC survivors. However, African American BC survivors were more likely to have hypertension (P < .01) and have a body mass index in the overweight and obese category (P < .001) than White BC survivors. Older BC survivors were more likely to receive cholesterol screening. DISCUSSION: This study demonstrates that BC survivors who have an established primary care provider have improved cholesterol screening and statin therapy based on their risk of developing chronic diseases.


Assuntos
Neoplasias da Mama , Sobreviventes de Câncer , Doenças Cardiovasculares , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Estudos de Casos e Controles , Detecção Precoce de Câncer , Feminino , Humanos , Lipídeos , Estudos Retrospectivos , Sobreviventes
7.
J Intellect Disabil Res ; 64(12): 956-969, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33034087

RESUMO

BACKGROUND: Ultrarare Marshall-Smith and Malan syndromes, caused by changes of the gene nuclear factor I X (NFIX), are characterised by intellectual disability (ID) and behavioural problems, although questions remain. Here, development and behaviour are studied and compared in a cross-sectional study, and results are presented with genetic findings. METHODS: Behavioural phenotypes are compared of eight individuals with Marshall-Smith syndrome (three male individuals) and seven with Malan syndrome (four male individuals). Long-term follow-up assessment of cognition and adaptive behaviour was possible in three individuals with Marshall-Smith syndrome. RESULTS: Marshall-Smith syndrome individuals have more severe ID, less adaptive behaviour, more impaired speech and less reciprocal interaction compared with individuals with Malan syndrome. Sensory processing difficulties occur in both syndromes. Follow-up measurement of cognition and adaptive behaviour in Marshall-Smith syndrome shows different individual learning curves over time. CONCLUSIONS: Results show significant between and within syndrome variability. Different NFIX variants underlie distinct clinical phenotypes leading to separate entities. Cognitive, adaptive and sensory impairments are common in both syndromes and increase the risk of challenging behaviour. This study highlights the value of considering behaviour within developmental and environmental context. To improve quality of life, adaptations to environment and treatment are suggested to create a better person-environment fit.


Assuntos
Anormalidades Múltiplas/epidemiologia , Anormalidades Múltiplas/fisiopatologia , Doenças do Desenvolvimento Ósseo/epidemiologia , Doenças do Desenvolvimento Ósseo/fisiopatologia , Anormalidades Craniofaciais/epidemiologia , Anormalidades Craniofaciais/fisiopatologia , Deficiência Intelectual/epidemiologia , Deficiência Intelectual/fisiopatologia , Transtornos Mentais/epidemiologia , Displasia Septo-Óptica/epidemiologia , Displasia Septo-Óptica/fisiopatologia , Distúrbios da Fala/epidemiologia , Adaptação Psicológica , Adolescente , Adulto , Criança , Pré-Escolar , Comorbidade , Estudos Transversais , Feminino , Seguimentos , Humanos , Masculino , Transtornos Mentais/fisiopatologia , Países Baixos/epidemiologia , Fenótipo , Distúrbios da Fala/fisiopatologia , Síndrome , Adulto Jovem
8.
Tob Use Insights ; 13: 1179173X20949270, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32874095

RESUMO

BACKGROUND: A cancer diagnosis is seen as a "teachable moment" for patients to consider changing their behavioral risk factors, such as smoking. It also offers an opportunity for oncology providers to engage in a dialogue about how they can support patients changing their smoking behaviors. Brief, evidence-based tobacco cessation treatment delivered by oncology providers through the 5As (Ask, Advise, Assess, Assist Arrange) model is recommended, but provision to cancer patients remains suboptimal. AIM: Explore patient-level factors associated with 5As receipt among current smokers with a newly diagnosed cancer. METHOD: A total of 303 patients self-reported whether they received each of the 5As during their most recent oncology care visit. Multivariable regression analyses were conducted to identify patient-level factors associated with 5As receipt. RESULTS: Oncology provider-delivered 5As rates ranged from 81.5% (Ask) to 30.7% (Arrange). 5As receipt was associated with: reporting lower illness-related stigma, diagnosis of a comorbid smoking-related disease, diagnosis of a smoking-related cancer, and diagnosis of a non-advanced cancer. CONCLUSION: Findings support previous literature in which smoking-related diagnoses were associated with greater receipt of 5As; however, disparities in the receipt of 5As existed for patients with more advanced cancer diagnoses and illness-related stigma. Inequities in the provision of quit assistance may further decrease treatment effectiveness and survival expectancy among certain patient populations. These findings are, therefore, important as they identify specific patient-level factors associated with lower 5As receipt among newly diagnosed cancer patients.

9.
BJS Open ; 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32671964

RESUMO

BACKGROUND: The effect of bariatric surgery on 'emotional eating' (EE) in people with obesity is unclear. This systematic review and meta-analysis aimed to examine changes in self-reported emotional eating behaviour after bariatric surgery. METHODS: Fifteen electronic databases were searched from inception to August 2019. Included studies encompassed patients undergoing primary bariatric surgery, quantitatively assessed EE, and reported EE scores before and after surgery in the same participants. Studies were excluded if they were not in English or available in full text. The systematic review and meta-analysis were conducted according to the PRISMA guidelines. Random-effects models were used for quantitative analysis. Study quality was assessed using the National Heart, Lung, and Blood Institute quality assessment tool for before-after (pre-post) studies with no control group. RESULTS: Some 23 studies containing 6749 participants were included in the qualitative synthesis, with follow-up of from 2 weeks to 48 months. EE scores decreased to 12 months after surgery. Results were mixed beyond 12 months. Quantitative synthesis of 17 studies (2811 participants) found that EE scores decreased by a standardized mean difference of 1·09 (95 per cent c.i. 0·76 to 1·42) 4-18 months after surgery, indicating a large effect size. CONCLUSION: Bariatric surgery may mitigate the tendency to eat in response to emotions in the short to medium term.


ANTECEDENTES: El efecto de la cirugía bariátrica sobre la "alimentación emocional" (emotional eating, EE) en personas con obesidad no esta claro. Esta revisión sistemática y metaanálisis tuvo como objetivo examinar los cambios en el comportamiento de la alimentación emocional referida por los mismos pacientes después de cirugía bariátrica. MÉTODOS: Se realizó una búsqueda en 15 bases de datos electrónicas desde el inicio de las mismas hasta agosto de 2019. Los estudios seleccionados incluían pacientes con cirugía bariátrica primaria, EE evaluada de forma cuantitativa, y descripción de las puntuaciones de EE antes y después de la cirugía en los mismos participantes. Se excluyeron estudios que no estuvieran publicados en inglés o si no se disponía del texto completo. Esta revisión sistemática y metaanálisis se llevó a cabo de acuerdo con las recomendaciones PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). Se utilizó un modelo de efectos aleatorios para el análisis cuantitativo. La calidad de los estudios individuales se evaluó utilizando la herramienta de evaluación de la calidad NHLBI para estudios de antes-después (pre-post) sin grupo control. RESULTADOS: Se incluyeron un total de 23 estudios con 6.749 participantes en la síntesis cualitativa, y un seguimiento de 2 semanas a 48 meses. Las puntuaciones EE disminuyeron a los 12 meses postoperatorios. Los resultados fueron variados más allá de los 12 meses. La síntesis cuantitativa de 17 estudios (2.811 participantes) encontró que las puntuaciones EE disminuyeron con una diferencia de medias ponderada de 1,09 (i.c. del 95% 0,76, 1,42) a los 4-18 meses tras la operación, lo que indica una magnitud de efecto grande. CONCLUSIÓN: La cirugía bariátrica puede atenuar la tendencia a comer en respuesta a las emociones en el corto y medio plazo.

12.
Biochem Biophys Res Commun ; 503(3): 1409-1414, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30025893

RESUMO

Muscle atrophy in metabolic conditions like chronic kidney disease (CKD) and diabetes are associated with glucocorticoid production, dysfunctional insulin/Akt/FoxO3 signaling and increased myostatin expression. We recently found that CREB, a transcription factor proposed to regulate myostatin expression, is highly phosphorylated in some wasting conditions. Based on a novel Akt-PDE3/4 signaling paradigm, we hypothesized that reduced Akt signaling contributes to CREB activation and myostatin expression. C2C12 myotubes were incubated with dexamethasone (Dex), an atrophy-inducing synthetic glucocorticoid. Akt/CREB signaling and myostatin expression were evaluated by immunoblot and qPCR analyses. Inhibitors of Akt, phosphodiesterase (PDE)-3/4, and protein kinase A (PKA) signaling were used to test our hypothesis. Incubating myotubes with Dex for 3-24 h inhibited Akt phosphorylation and enhanced CREB phosphorylation as well as myostatin mRNA and protein. Inhibition of PI3K/Akt signaling with LY294002 similarly increased CREB phosphorylation. Isobutyl-methylxanthine (IBMX, a pan PDE inhibitor), milrinone (PDE3 inhibitor) and rolipram (PDE4 inhibitor) augmented CREB phosphorylation and myostatin expression. Inhibition of protein kinase A by PKI reverted Dex- or IBMX-induced CREB phosphorylation and myostatin expression. Our study provides evidence supporting a newly identified mechanism by which a glucocorticoid-related reduction in Akt signaling contributes to myostatin expression via CREB activation.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Glucocorticoides/farmacologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Miostatina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Células Cultivadas , Camundongos , Fibras Musculares Esqueléticas/metabolismo , Miostatina/biossíntese , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo
13.
J Cachexia Sarcopenia Muscle ; 9(4): 755-770, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29582582

RESUMO

BACKGROUND: The treatment of muscle wasting is accompanied by benefits in other organs, possibly resulting from muscle-organ crosstalk. However, how the muscle communicates with these organs is less understood. Two microRNAs (miRs), miR-23a and miR-27a, are located together in a gene cluster and regulate proteins that are involved in the atrophy process. MiR-23a/27a has been shown to reduce muscle wasting and act as an anti-fibrotic agent. We hypothesized that intramuscular injection of miR-23a/27a would counteract both muscle wasting and renal fibrosis lesions in a streptozotocin-induced diabetic model. METHODS: We generated an adeno-associated virus (AAV) that overexpresses the miR-23a∼27a∼24-2 precursor RNA and injected it into the tibialis anterior muscle of streptozotocin-induced diabetic mice. Muscle cross-section area (immunohistology plus software measurement) and muscle function (grip strength) were used to evaluate muscle atrophy. Fibrosis-related proteins were measured by western blot to monitor renal damage. In some cases, AAV-GFP was used to mimic the miR movement in vivo, allowing us to track organ redistribution by using the Xtreme Imaging System. RESULTS: The injection of AAV-miR-23a/27a increased the levels of miR-23a and miR-27a as well as increased phosphorylated Akt, attenuated the levels of FoxO1 and PTEN proteins, and reduced the abundance of TRIM63/MuRF1 and FBXO32/atrogin-1 in skeletal muscles. It also decreased myostatin mRNA and protein levels as well as the levels of phosphorylated pSMAD2/3. Provision of miR-23a/27a attenuates the diabetes-induced reduction of muscle cross-sectional area and muscle function. Curiously, the serum BUN of diabetic animals was reduced in mice undergoing the miR-23a/27a intervention. Renal fibrosis, evaluated by Masson trichromatic staining, was also decreased as were kidney levels of phosphorylated SMAD2/3, alpha smooth muscle actin, fibronectin, and collagen. In diabetic mice injected intramuscularly with AAV-GFP, GFP fluorescence levels in the kidneys showed linear correlation with the levels in injected muscle when examined by linear regression. Following intramuscular injection of AAV-miR-23a∼27a∼24-2, the levels of miR-23a and miR-27a in serum exosomes and kidney were significantly increased compared with samples from control virus-injected mice; however, no viral DNA was detected in the kidney. CONCLUSIONS: We conclude that overexpression of miR-23a/27a in muscle prevents diabetes-induced muscle cachexia and attenuates renal fibrosis lesions via muscle-kidney crosstalk. Further, this crosstalk involves movement of miR potentially through muscle originated exosomes and serum distribution without movement of AAV. These results could provide new approaches for developing therapeutic strategies for diabetic nephropathy with muscle wasting.


Assuntos
Regulação da Expressão Gênica , Rim/metabolismo , Rim/patologia , MicroRNAs/genética , Atrofia Muscular/genética , Atrofia Muscular/metabolismo , Animais , Dependovirus/genética , Modelos Animais de Doenças , Fibrose , Vetores Genéticos/genética , Camundongos , Modelos Biológicos , Imagem Molecular , Atrofia Muscular/patologia , Miostatina/metabolismo , Células Satélites de Músculo Esquelético/metabolismo , Transdução de Sinais , Transdução Genética
14.
AJNR Am J Neuroradiol ; 38(10): 1884-1891, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28882867

RESUMO

BACKGROUND: Brain imaging in diffuse glioma is used for diagnosis, treatment planning, and follow-up. PURPOSE: In this meta-analysis, we address the diagnostic accuracy of imaging to delineate diffuse glioma. DATA SOURCES: We systematically searched studies of adults with diffuse gliomas and correlation of imaging with histopathology. STUDY SELECTION: Study inclusion was based on quality criteria. Individual patient data were used, if available. DATA ANALYSIS: A hierarchic summary receiver operating characteristic method was applied. Low- and high-grade gliomas were analyzed in subgroups. DATA SYNTHESIS: Sixty-one studies described 3532 samples in 1309 patients. The mean Standard for Reporting of Diagnostic Accuracy score (13/25) indicated suboptimal reporting quality. For diffuse gliomas as a whole, the diagnostic accuracy was best with T2-weighted imaging, measured as area under the curve, false-positive rate, true-positive rate, and diagnostic odds ratio of 95.6%, 3.3%, 82%, and 152. For low-grade gliomas, the diagnostic accuracy of T2-weighted imaging as a reference was 89.0%, 0.4%, 44.7%, and 205; and for high-grade gliomas, with T1-weighted gadolinium-enhanced MR imaging as a reference, it was 80.7%, 16.8%, 73.3%, and 14.8. In high-grade gliomas, MR spectroscopy (85.7%, 35.0%, 85.7%, and 12.4) and 11C methionine-PET (85.1%, 38.7%, 93.7%, and 26.6) performed better than the reference imaging. LIMITATIONS: True-negative samples were underrepresented in these data, so false-positive rates are probably less reliable than true-positive rates. Multimodality imaging data were unavailable. CONCLUSIONS: The diagnostic accuracy of commonly used imaging is better for delineation of low-grade gliomas than high-grade gliomas on the basis of limited evidence. Improvement is indicated from advanced techniques, such as MR spectroscopy and PET.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Glioma/diagnóstico por imagem , Neuroimagem/métodos , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Feminino , Glioma/patologia , Humanos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Curva ROC
15.
J Am Soc Nephrol ; 28(9): 2631-2640, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28400445

RESUMO

Muscle atrophy is a frequent complication of CKD, and exercise can attenuate the process. This study investigated the role of microRNA-23a (miR-23a) and miR-27a in the regulation of muscle mass in mice with CKD. These miRs are located in a gene cluster that is regulated by the transcription factor NFAT. CKD mice expressed less miR-23a in muscle than controls, and resistance exercise (muscle overload) increased the levels of miR-23a and miR-27a in CKD mice. Injection of an adeno-associated virus encoding the miR-23a/27a/24-2 precursor RNA into the tibialis anterior muscles of normal and CKD mice led to increases in mature miR-23a and miR-27a but not miR-24-2 in the muscles of both cohorts. Overexpression of miR-23a/miR-27a in CKD mice attenuated muscle loss, improved grip strength, increased the phosphorylation of Akt and FoxO1, and decreased the activation of phosphatase and tensin homolog (PTEN) and FoxO1 and the expression of TRIM63/MuRF1 and FBXO32/atrogin-1 proteins. Provision of miR-23a/miR-27a also reduced myostatin expression and downstream SMAD-2/3 signaling, decreased activation of caspase-3 and -7, and increased the expression of markers of muscle regeneration. Lastly, in silico miR target analysis and luciferase reporter assays in primary satellite cells identified PTEN and caspase-7 as targets of miR-23a and FoxO1 as a target of miR-27a in muscle. These findings provide new insights about the roles of the miR-23a/27a-24-2 cluster in CKD-induced muscle atrophy in mice and suggest a mechanism by which exercise helps to maintain muscle mass.


Assuntos
MicroRNAs/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Insuficiência Renal Crônica/complicações , Animais , Atrofia/etiologia , Atrofia/genética , Atrofia/metabolismo , Atrofia/prevenção & controle , Caspase 3/metabolismo , Caspase 7/metabolismo , Citocinas/genética , Proteína Forkhead Box O1/metabolismo , Camundongos , MicroRNAs/genética , Proteínas Musculares/metabolismo , Força Muscular , Miostatina/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Fosforilação , Condicionamento Físico Animal/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/metabolismo , Proteínas Ligases SKP Culina F-Box/metabolismo , Transdução de Sinais , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Transdução Genética , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
16.
Anaesthesia ; 70(11): 1320, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26449294
17.
Artigo em Inglês | MEDLINE | ID: mdl-27275017

RESUMO

Mesenchymal stem cells (MSCs) are a multipotent cell population acquired most prominently from bone marrow with the capacity to differentiate into osteoblasts, chondrocytes, adipocytes, and others. MSCs demonstrate the capacity to home to sites of injury and contribute to tissue repair. Sphingosine 1-phosphate (S1P) is a biologically active sphingolipid impacting proliferation, apoptosis, inflammation, and angiogenesis with changes in S1P concentration providing significant implications for various disease conditions including cancer, diabetes, and cardiac disease. These functions are primarily mediated by interactions with 5 G-protein coupled S1P receptors (S1PR1-5). In this paper, we demonstrate that inhibition of S1PR2 results in increased MSC clonogenicity, migration, and proliferation; features dependent on Erk phosphorylation. Furthermore, decreased S1PR2 expression decreases the differentiation of MSCs into adipocytes and mature osteoblasts that may be the result of increased expression of MSC pluripotency factors including Nanog, Sox-9, and Oct-4. Inhibition of S1PR1 and S1PR3 in contrast does not impact MSC migration or Erk activation although increased proliferation is observed. In the study, we describe the essential role of S1PR2 in MSC differentiation pathways through modification of pluripotency factors. We propose a MAPK dependent mechanism through S1PR2 inhibition that promotes equally multipotent MSC proliferation.

19.
Clin Oncol (R Coll Radiol) ; 26(7): 385-94, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24882149

RESUMO

The scientific basis for the surgical management of patients with glioma is rapidly evolving. The infiltrative nature of these cancers precludes a surgical cure, but despite this, cytoreductive surgery remains central to high-quality patient care. In addition to tissue sampling for accurate histopathological diagnosis and molecular genetic characterisation, clinical benefit from decompression of space-occupying lesions and microsurgical cytoreduction has been reported in patients with different grades of glioma. By integrating advanced surgical techniques with molecular genetic characterisation of the disease and targeted radiotherapy and chemotherapy, it is possible to construct a programme of personalised surgical therapy throughout the patient journey. The goal of therapeutic packages tailored to each patient is to optimise patient safety and clinical outcome and must be delivered in a multidisciplinary setting. Here we review the current concepts that underlie surgical subspecialisation in the management of patients with glioma.


Assuntos
Neoplasias Encefálicas/cirurgia , Glioma/cirurgia , Humanos
20.
J Nutr Biochem ; 25(8): 868-74, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24835079

RESUMO

Saturated fatty acids like palmitate contribute to muscle atrophy in a number of conditions (e.g., type II diabetes) by altering insulin signaling. Akt is a key modulator of protein balance that inhibits the FoxO transcription factors (e.g., FoxO3) which selectively induce the expression of atrophy-inducing genes (atrogenes) in the ubiquitin-proteasome and autophagy-lysosome systems. Conversely, omega-3 polyunsaturated fatty acids have beneficial effects on insulin signaling and may preserve muscle mass. In an earlier report, the omega-3 fatty acid docosahexaenoic acid (DHA) protected myotubes from palmitate-induced atrophy; the mechanisms underlying the alterations in protein metabolism were not identified. This study investigated whether DHA prevents a palmitate-induced increase in proteolysis by restoring Akt/FoxO signaling. Palmitate increased the rate of protein degradation, while cotreatment with DHA prevented the response. Palmitate reduced the activation state of Akt and increased nuclear FoxO3 protein while decreasing its cytosolic level. Palmitate also increased the messenger RNAs (mRNAs) of two FoxO3 atrogene targets, the E3 ubiquitin ligase atrogin-1/MAFbx and the autophagy mediator Bnip3. DHA attenuated the effects of palmitate on Akt activation, FoxO3 localization and atrogene mRNAs. DHA, alone or in combination with palmitate and decreased the ratio of LC3B-II:LC3B-I protein as well as the rate of autophagosome formation, as indicated by reduced LC3B-II protein in the presence of 10 mmol/L methylamine, suggesting an independent effect of DHA on the macroautophagy pathway. These data indicate that palmitate induces myotube atrophy, at least in part, by activating multiple proteolytic systems and that DHA counters the catabolic effects of palmitate by restoring Akt/FoxO signaling.


Assuntos
Ácidos Docosa-Hexaenoicos/farmacologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Palmitatos/efeitos adversos , Animais , Autofagia/efeitos dos fármacos , Linhagem Celular/efeitos dos fármacos , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Fibras Musculares Esqueléticas/patologia , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Atrofia Muscular/patologia , Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Ligases SKP Culina F-Box/genética , Proteínas Ligases SKP Culina F-Box/metabolismo , Transdução de Sinais/efeitos dos fármacos
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