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1.
Immunology ; 169(3): 260-270, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36840585

RESUMO

The cell surface antigen CD14 is primarily understood to act as a co-receptor for toll-like receptors (TLRs) to activate innate immunity responses to pathogens and tissue injury in macrophages and monocytes. However, roles for CD14 are increasingly being uncovered in disease responses in epithelial and endothelial cells. Consistent with these broader functions, CD14 expression is altered in a variety of non-immune cell types in response to a several of disease states. Moreover, soluble CD14 activated by factors from both pathogens and tissue damage may initiate signalling in a variety of non-immune cells. This review examined the current understanding CD14 in innate immunity as well as its potential functions in nonimmune cells and associated human diseases.


Assuntos
Células Endoteliais , Receptor 4 Toll-Like , Humanos , Células Endoteliais/metabolismo , Receptor 4 Toll-Like/metabolismo , Lipopolissacarídeos , Receptores Toll-Like , Macrófagos , Receptores de Lipopolissacarídeos/metabolismo
2.
Int J Mol Sci ; 24(19)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37834011

RESUMO

MicroRNA-29a (miR-29a) is a well characterized fibro-inflammatory molecule and its aberrant expression is linked to a variety of pathological liver conditions. The long-term effects of a high-fat diet (HFD) in combination with different levels of EtOH consumption on miR-29a expression and liver pathobiology are unknown. Mice at 8 weeks of age were divided into five groups (calorie-matched diet plus water (CMD) as a control group, HFD plus water (HFD) as a liver disease group, HFD plus 2% EtOH (HFD + 2% E), HFD + 10% E, and HFD + 20% E as intervention groups) and fed for 4, 13, 26, or 39 weeks. At each time point, analyses were performed for liver weight/body weight (BW) ratio, AST/ALT ratio, as well as liver histology assessments, which included inflammation, estimated fat deposition, lipid area, and fibrosis. Hepatic miR-29a was measured and correlations with phenotypic traits were determined. Four-week feeding produced no differences between the groups on all collected phenotypic traits or miR-29a expression, while significant effects were observed after 13 weeks, with EtOH concentration-specific induction of miR-29a. A turning point for most of the collected traits was apparent at 26 weeks, and miR-29a was significantly down-regulated with increasing liver injury. Overall, miR-29a up-regulation was associated with a lower liver/BW ratio, fat deposition, inflammation, and fibrosis, suggesting a protective role of miR-29a against liver disease progression. A HFD plus increasing concentrations of EtOH produces progressive adverse effects on the liver, with no evidence of beneficial effects of low-dose EtOH consumption. Moreover, miR-29a up-regulation is associated with less severe liver injury.


Assuntos
MicroRNAs , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo , Etanol/toxicidade , Etanol/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Cirrose Hepática/metabolismo , Inflamação/metabolismo , MicroRNAs/metabolismo , Água/metabolismo , Camundongos Endogâmicos C57BL
3.
Cytokine ; 159: 155972, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36054964

RESUMO

Musculoskeletal diseases such as muscular dystrophy, cachexia, osteoarthritis, and rheumatoid arthritis impair overall physical health and reduce survival. Patients suffer from pain, dysfunction, and dysmobility due to inflammation and fibrosis in bones, muscles, and joints, both locally and systemically. The Interleukin-6 (IL-6) family of cytokines, most notably IL-6, is implicated in musculoskeletal disorders and cachexia. Here we show elevated circulating levels of OSM in murine pancreatic cancer cachexia and evaluate the effects of the IL-6 family member, Oncostatin M (OSM), on muscle and bone using adeno-associated virus (AAV) mediated over-expression of murine OSM in wildtype and IL-6 deficient mice. Initial studies with high titer AAV-OSM injection yielded high circulating OSM and IL-6, thrombocytosis, inflammation, and 60% mortality without muscle loss within 4 days. Subsequently, to mimic OSM levels in cachexia, a lower titer of AAV-OSM was used in wildtype and Il6 null mice, observing effects out to 4 weeks and 12 weeks. AAV-OSM caused muscle atrophy and fibrosis in the gastrocnemius, tibialis anterior, and quadriceps of the injected limb, but these effects were not observed on the non-injected side. In contrast, OSM induced both local and distant trabecular bone loss as shown by reduced bone volume, trabecular number, and thickness, and increased trabecular separation. OSM caused cardiac dysfunction including reduced ejection fraction and reduced fractional shortening. RNA-sequencing of cardiac muscle revealed upregulation of genes related to inflammation and fibrosis. None of these effects were different in IL-6 knockout mice. Thus, OSM induces local muscle atrophy, systemic bone loss, tissue fibrosis, and cardiac dysfunction independently of IL-6, suggesting a role for OSM in musculoskeletal conditions with these characteristics, including cancer cachexia.


Assuntos
Cardiopatias , Interleucina-6 , Animais , Caquexia , Fibrose , Inflamação , Interleucina-6/farmacologia , Camundongos , Camundongos Knockout , Atrofia Muscular , Oncostatina M/farmacologia , RNA
5.
J Cell Mol Med ; 25(2): 784-800, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33274592

RESUMO

With a plethora of molecularly targeted agents under investigation in cancer, a clear need exists to understand which pathways can be targeted simultaneously with multiple agents to elicit a maximal killing effect on the tumour. Combination therapy provides the most promise in difficult to treat cancers such as pancreatic. Ref-1 is a multifunctional protein with a role in redox signalling that activates transcription factors such as NF-κB, AP-1, HIF-1α and STAT3. Formerly, we have demonstrated that dual targeting of Ref-1 (redox factor-1) and STAT3 is synergistic and decreases cell viability in pancreatic cancer cells. Data presented here extensively expands upon this work and provides further insights into the relationship of STAT3 and Ref-1 in multiple cancer types. Using targeted small molecule inhibitors, Ref-1 redox signalling was blocked along with STAT3 activation, and tumour growth evaluated in the presence and absence of the relevant tumour microenvironment. Our study utilized qPCR, cytotoxicity and in vivo analysis of tumour and cancer-associated fibroblasts (CAF) response to determine the synergy of Ref-1 and STAT3 inhibitors. Overall, pancreatic tumours grown in the presence of CAFs were sensitized to the combination of STAT3 and Ref-1 inhibition in vivo. In vitro bladder and pancreatic cancer demonstrated the most synergistic responses. By disabling both of these important pathways, this combination therapy has the capacity to hinder crosstalk between the tumour and its microenvironment, leading to improved tumour response.


Assuntos
DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Fator de Transcrição STAT3/metabolismo , Animais , Benzofuranos/farmacologia , Western Blotting , Linhagem Celular Tumoral , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Células HCT116 , Humanos , Imuno-Histoquímica , Camundongos , Naftoquinonas/farmacologia , Nitrilas , Neoplasias Pancreáticas/genética , Pirazóis/farmacologia , Pirimidinas , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT3/genética , Microambiente Tumoral/efeitos dos fármacos
6.
Dig Dis Sci ; 66(9): 3062-3073, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33074470

RESUMO

BACKGROUND: Alcoholic hepatitis (AH) is a serious clinical syndrome often associated with muscle wasting. Myostatin, a member of the transforming growth factor-ß superfamily, has been studied in diseases with muscle wasting; however, the role of myostatin in AH is unknown. AIMS: To investigate the association between myostatin, clinical variables, and outcomes in AH. METHODS: We analyzed data for cases of AH and controls of heavy drinkers (HD) in TREAT001 (NCT02172898) with serum myostatin levels (AH: n = 131, HD: n = 124). We compared characteristics between the two groups at baseline, 30, and 90 days and explored correlations between myostatin and clinical variables. We then modeled the relationship of myostatin to other variables, including mortality. RESULTS: Baseline median myostatin was lower in AH compared to HD (males: 1.58 vs 3.06 ng/ml, p < 0.001; females: 0.84 vs 2.01 ng/ml, p < 0.001). In multivariable linear regression, bilirubin, WBC, and platelet count remained negatively correlated with myostatin in AH. AH females who died at 90 days had significantly lower myostatin, but in a multivariable logistic model with MELD and myostatin, only MELD remained significantly associated with 90-day mortality. During 1-year follow-up, AH cases (n = 30) demonstrated an increase in myostatin (mean, 1.73 ng/ml) which correlated with decreasing MELD scores (ρ = - 0.42, p = 0.01). CONCLUSIONS: Myostatin levels are significantly lower in AH compared to HD and are negatively correlated with total bilirubin, WBC, and platelet count. Myostatin increased as patients experienced decreases in MELD. Overall, myostatin demonstrated a dynamic relationship with AH outcomes and future studies are needed to understand the prognostic role of myostatin in AH.


Assuntos
Hepatite Alcoólica , Falência Renal Crônica , Fígado/patologia , Miostatina/sangue , Consumo de Bebidas Alcoólicas , Bilirrubina/sangue , Biomarcadores/sangue , Biópsia/métodos , Progressão da Doença , Feminino , Células Hep G2 , Hepatite Alcoólica/sangue , Hepatite Alcoólica/diagnóstico , Humanos , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/mortalidade , Contagem de Leucócitos/métodos , Testes de Função Hepática/métodos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Contagem de Plaquetas/métodos , Prognóstico
7.
Int J Mol Sci ; 22(16)2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34445339

RESUMO

Both agonist studies and loss-of-function models indicate that PPARγ plays an important role in cutaneous biology. Since PPARγ has a high level of basal activity, we hypothesized that epidermal PPARγ would regulate normal homeostatic processes within the epidermis. In this current study, we performed mRNA sequencing and differential expression analysis of epidermal scrapings from knockout mice and wildtype littermates. Pparg-/-epi mice exhibited a 1.5-fold or greater change in the expression of 11.8% of 14,482 identified transcripts. Up-regulated transcripts included those for a large number of cytokines/chemokines and their receptors, as well as genes associated with inflammasome activation and keratinization. Several of the most dramatically up-regulated pro-inflammatory genes in Pparg-/-epi mouse skin included Igfl3, 2610528A11Rik, and Il1f6. RT-PCR was performed from RNA obtained from non-lesional full-thickness skin and verified a marked increase in these transcripts, as well as transcripts for Igflr1, which encodes the receptor for Igfl3, and the 2610528A11Rik receptor (Gpr15). Transcripts for Il4 were detected in Pparg-/-epi mouse skin, but transcripts for Il17 and Il22 were not detected. Down-regulated transcripts included sebaceous gland markers and a number of genes associated with lipid barrier formation. The change in these transcripts correlates with an asebia phenotype, increased transepidermal water loss, alopecia, dandruff, and the appearance of spontaneous inflammatory skin lesions. Histologically, non-lesional skin showed hyperkeratosis, while inflammatory lesions were characterized by dermal inflammation and epidermal acanthosis, spongiosis, and parakeratosis. In conclusion, loss of epidermal Pparg alters a substantial set of genes that are associated with cutaneous inflammation, keratinization, and sebaceous gland function. The data indicate that epidermal PPARγ plays an important role in homeostatic epidermal function, particularly epidermal differentiation, barrier function, sebaceous gland development and function, and inflammatory signaling.


Assuntos
Dermatite/genética , Epiderme/metabolismo , PPAR gama/fisiologia , Fenômenos Fisiológicos da Pele/genética , Animais , Células Cultivadas , Dermatite/metabolismo , Dermatite/patologia , Dermatite/fisiopatologia , Epiderme/fisiologia , Homeostase/genética , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Especificidade de Órgãos/genética , PPAR gama/genética , PPAR gama/metabolismo
8.
Curr Osteoporos Rep ; 18(6): 646-654, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33044689

RESUMO

PURPOSE OF REVIEW: Cachexia, a feature of cancer and other chronic diseases, is marked by progressive weight loss and skeletal muscle wasting. This review aims to highlight the sex differences in manifestations of cancer cachexia in patients, rodent models, and our current understanding of the potential mechanisms accounting for these differences. RECENT FINDINGS: Male cancer patients generally have higher prevalence of cachexia, greater weight loss or muscle wasting, and worse outcomes compared with female cancer patients. Knowledge is increasing about sex differences in muscle fiber type and function, mitochondrial metabolism, global gene expression and signaling pathways, and regulatory mechanisms at the levels of sex chromosomes vs. sex hormones; however, it is largely undetermined how such sex differences directly affect the susceptibility to stressors leading to muscle wasting in cancer cachexia. Few studies have investigated basic mechanisms underlying sex differences in cancer cachexia. A better understanding of sex differences would improve cachexia treatment in both sexes.


Assuntos
Caquexia/etiologia , Caquexia/fisiopatologia , Neoplasias/complicações , Neoplasias/fisiopatologia , Animais , Feminino , Humanos , Masculino , Fatores Sexuais
9.
J Am Soc Nephrol ; 30(10): 1898-1909, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31501355

RESUMO

BACKGROUND: Reduced bone and muscle health in individuals with CKD contributes to their higher rates of morbidity and mortality. METHODS: We tested the hypothesis that voluntary wheel running would improve musculoskeletal health in a CKD rat model. Rats with spontaneous progressive cystic kidney disease (Cy/+ IU) and normal littermates (NL) were given access to a voluntary running wheel or standard cage conditions for 10 weeks starting at 25 weeks of age when the rats with kidney disease had reached stage 2-3 of CKD. We then measured the effects of wheel running on serum biochemistry, tissue weight, voluntary grip strength, maximal aerobic capacity (VO2max), body composition and bone micro-CT and mechanics. RESULTS: Wheel running improved serum biochemistry with decreased creatinine, phosphorous, and parathyroid hormone in the rats with CKD. It improved muscle strength, increased time-to-fatigue (for VO2max), reduced cortical porosity and improved bone microarchitecture. The CKD rats with voluntary wheel access also had reduced kidney cystic weight and reduced left ventricular mass index. CONCLUSIONS: Voluntary wheel running resulted in multiple beneficial systemic effects in rats with CKD and improved their physical function. Studies examining exercise interventions in patients with CKD are warranted.


Assuntos
Distúrbio Mineral e Ósseo na Doença Renal Crônica/terapia , Atividade Motora , Animais , Modelos Animais de Doenças , Feminino , Masculino , Ratos
10.
Int J Mol Sci ; 21(18)2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32932869

RESUMO

Despite advances in treatment and care, burn trauma remains the fourth most common type of traumatic injury. Burn-induced cardiac failure is a key factor for patient mortality, especially during the initial post-burn period (the first 24 to 48 h). Mitochondria, among the most important subcellular organelles in cardiomyocytes, are a central player in determining the severity of myocardial damage. Defects in mitochondrial function and structure are involved in pathogenesis of numerous myocardial injuries and cardiovascular diseases. In this article, we comprehensively review the current findings on cardiac mitochondrial pathological changes and summarize burn-impaired mitochondrial respiration capacity and energy supply, induced mitochondrial oxidative stress, and increased cell death. The molecular mechanisms underlying these alterations are discussed, along with the possible influence of other biological variables. We hope this review will provide useful information to explore potential therapeutic approaches that target mitochondria for cardiac protection following burn injury.


Assuntos
Queimaduras/patologia , Mitocôndrias Cardíacas/patologia , Ferimentos e Lesões/patologia , Animais , Humanos , Miocárdio/patologia , Miócitos Cardíacos/patologia
11.
Oncologist ; 24(5): 691-701, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30591550

RESUMO

Unintentional weight loss in patients with pancreatic cancer is highly prevalent and contributes to low therapeutic tolerance, reduced quality of life, and overall mortality. Weight loss in pancreatic cancer can be due to anorexia, malabsorption, and/or cachexia. Proper supportive care can stabilize or reverse weight loss in patients and improve outcomes. We review the literature on supportive care relevant to pancreatic cancer patients, and offer evidence-based recommendations that include expert nutritional assessment, counseling, supportive measures to ensure adequate caloric intake, pancreatic enzyme supplementation, nutritional supplement replacement, orexigenic agents, and exercise. Pancreatic Cancer Action Network-supported initiatives will spearhead the dissemination and adoption of these best supportive care practices. IMPLICATIONS FOR PRACTICE: Weight loss in pancreatic cancer patients is endemic, as 85% of pancreatic cancer patients meet the classic definition of cancer cachexia. Despite its significant prevalence and associated morbidity, there is no established approach to this disease entity. It is believed that this is due to an important knowledge gap in understanding the underlying biology and lack of optimal treatment approaches. This article reviews the literature regarding pancreas cancer-associated weight loss and establishes a new framework from which to view this complex clinical problem. An improved approach and understanding will help educate clinicians, improve clinical care, and provide more clarity for future clinical investigation.


Assuntos
Caquexia/diagnóstico , Neoplasias Pancreáticas/complicações , Qualidade de Vida/psicologia , Redução de Peso/fisiologia , Humanos , Prevalência
12.
Dig Dis Sci ; 64(1): 93-101, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30284135

RESUMO

INTRODUCTION: Loss of hepatic epidermal growth factor receptor (EGFR) expression is a cause for the increased perioperative risk for complications and death in patients with obesity and fatty liver undergoing liver resection. Herein, we set out to identify agents that might increase EGFR expression and improve recovery for patients with fatty liver undergoing resection. Using the diet-induced obese (DIO) mouse model of fatty liver, we examined resveratrol as a therapy to induce EGFR expression and improve outcomes following 80% partial hepatectomy (PH) in a murine model. METHODS: DIO mice were fed resveratrol or carrier control by gavage. EGFR expression and the response to major (80%) PH were examined. RESULTS: Based on an Illumina analysis, resveratrol was identified as increasing EGFR gene expression in A549 cells. Resveratrol was observed to also increase EGFR protein expression in A549 cells. DIO mice fed resveratrol by gavage (75 mg/kg) demonstrated an increased EGFR expression without the identified hepatic toxicity. Resveratrol and control mice subjected to 80% PH, a model of high mortality hepatectomy in DIO mice, demonstrated macroscopically decreased fatty liver and fewer liver hemorrhagic petechiae. Resveratrol pretreatment ameliorated liver injury and accelerated regeneration of the hepatic remnant after 80% PH including decreasing serum ALT and bilirubin, while increasing hepatic PCNA expression. Resveratrol increased induction of p-STAT3 and p-AKT after 80% hepatectomy. Resveratrol pretreatment significantly improved survival rates in DIO mice undergoing extended 80% PH. CONCLUSIONS: Oral resveratrol restores EGFR expression in fatty liver. Resveratrol may be a promising protective agent in instances where extensive hepatic resection of fatty liver is required.


Assuntos
Dieta Hiperlipídica , Hepatectomia , Regeneração Hepática/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/cirurgia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/cirurgia , Obesidade/etiologia , Resveratrol/farmacologia , Células A549 , Animais , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Receptores ErbB/metabolismo , Humanos , Fígado/metabolismo , Fígado/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Obesidade/metabolismo , Obesidade/fisiopatologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Recuperação de Função Fisiológica , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima
13.
Gut ; 67(2): 320-332, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-27797936

RESUMO

OBJECTIVE: Limited efficacy of immune checkpoint inhibitors in pancreatic ductal adenocarcinoma (PDAC) has prompted investigation into combination therapy. We hypothesised that interleukin 6 (IL-6) blockade would modulate immunological features of PDAC and enhance the efficacy of anti-programmed death-1-ligand 1 (PD-L1) checkpoint inhibitor therapy. DESIGN: Transcription profiles and IL-6 secretion from primary patient-derived pancreatic stellate cells (PSCs) were analyzed via Nanostring and immunohistochemistry, respectively. In vivo efficacy and mechanistic studies were conducted with antibodies (Abs) targeting IL-6, PD-L1, CD4 or CD8 in subcutaneous or orthotopic models using Panc02, MT5 or KPC-luc cell lines; and the aggressive, genetically engineered PDAC model (KrasLSL-G12D, Trp53LSL-R270H, Pdx1-cre, Brca2F/F (KPC-Brca2 mice)). Systemic and local changes in immunophenotype were measured by flow cytometry or immunohistochemical analysis. RESULTS: PSCs (n=12) demonstrated prominent IL-6 expression, which was localised to stroma of tumours. Combined IL-6 and PD-L1 blockade elicited efficacy in mice bearing subcutaneous MT5 (p<0.02) and Panc02 tumours (p=0.046), which was accompanied by increased intratumoural effector T lymphocytes (CD62L-CD44-). CD8-depleting but not CD4-depleting Abs abrogated the efficacy of combined IL-6 and PD-L1 blockade in mice bearing Panc02 tumours (p=0.0016). This treatment combination also elicited significant antitumour activity in mice bearing orthotopic KPC-luc tumours and limited tumour progression in KPC-Brca2 mice (p<0.001). Histological analysis revealed increased T-cell infiltration and reduced α-smooth muscle actin cells in tumours from multiple models. Finally, IL-6 and PD-L1 blockade increased overall survival in KPC-Brca2 mice compared with isotype controls (p=0.0012). CONCLUSIONS: These preclinical results indicate that targeted inhibition of IL-6 may enhance the efficacy of anti-PD-L1 in PDAC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Carcinoma Ductal Pancreático/tratamento farmacológico , Interleucina-6/antagonistas & inibidores , Neoplasias Pancreáticas/tratamento farmacológico , Actinas/metabolismo , Animais , Antineoplásicos Imunológicos/administração & dosagem , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Carcinoma Ductal Pancreático/imunologia , Carcinoma Ductal Pancreático/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Feminino , Humanos , Receptores de Hialuronatos/metabolismo , Interleucina-6/imunologia , Interleucina-6/metabolismo , Janus Quinases/metabolismo , Selectina L/metabolismo , Linfócitos do Interstício Tumoral/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/metabolismo , Células Estreladas do Pâncreas/imunologia , Células Estreladas do Pâncreas/metabolismo , Fatores de Transcrição STAT/metabolismo , Taxa de Sobrevida , Células Th1/metabolismo , Microambiente Tumoral/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Semin Cell Dev Biol ; 54: 28-41, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26860754

RESUMO

Weight loss is diagnostic of cachexia, a debilitating syndrome contributing mightily to morbidity and mortality in cancer. Most research has probed mechanisms leading to muscle atrophy and adipose wasting in cachexia; however cachexia is a truly systemic phenomenon. Presence of the tumor elicits an inflammatory response and profound metabolic derangements involving not only muscle and fat, but also the hypothalamus, liver, heart, blood, spleen and likely other organs. This global response is orchestrated in part through circulating cytokines that rise in conditions of cachexia. Exogenous Interleukin-6 (IL6) and related cytokines can induce most cachexia symptomatology, including muscle and fat wasting, the acute phase response and anemia, while IL-6 inhibition reduces muscle loss in cancer. Although mechanistic studies are ongoing, certain of these cachexia phenotypes have been causally linked to the cytokine-activated transcription factor, STAT3, including skeletal muscle wasting, cardiac dysfunction and hypothalamic inflammation. Correlative studies implicate STAT3 in fat wasting and the acute phase response in cancer cachexia. Parallel data in non-cancer models and disease states suggest both pathological and protective functions for STAT3 in other organs during cachexia. STAT3 also contributes to cancer cachexia through enhancing tumorigenesis, metastasis and immune suppression, particularly in tumors associated with high prevalence of cachexia. This review examines the evidence linking STAT3 to multi-organ manifestations of cachexia and the potential and perils for targeting STAT3 to reduce cachexia and prolong survival in cancer patients.


Assuntos
Caquexia/etiologia , Caquexia/metabolismo , Inflamação/patologia , Neoplasias/complicações , Fator de Transcrição STAT3/metabolismo , Animais , Humanos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Especificidade de Órgãos
15.
Am J Physiol Endocrinol Metab ; 313(4): E440-E449, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28655714

RESUMO

Hepatic steatosis is a common histological finding in obese patients. Even mild steatosis is associated with delayed hepatic regeneration and poor outcomes following liver resection or transplantation. We sought to identify and target molecular pathways that mediate this dysfunction. Lean mice and mice made obese through feeding of a high-fat, hypercaloric diet underwent 70 or 80% hepatectomy. After 70% resection, obese mice demonstrated 100% survival but experienced increased liver injury, reduced energy stores, reduced mitoses, increased necroapoptosis, and delayed recovery of liver mass. Increasing liver resection to 80% was associated with mortality of 40% in lean and 80% in obese mice (P < 0.05). Gene expression profiling showed decreased epidermal growth factor receptor (EGFR) in fatty liver. Meta-analysis of expression studies in mice, rats, and patients also demonstrated reduction of EGFR in fatty liver. In mice, both EGFR and phosphorylated EGFR decreased with increasing percent body fat. Hydrodynamic transfection of EGFR plasmids in mice corrected fatty liver regeneration, reducing liver injury, increasing proliferation, and improving survival after 80% resection. Loss of EGFR expression is rate limiting for liver regeneration in obesity. Therapies directed at increasing EGFR in steatosis might promote liver regeneration and survival following hepatic resection or transplantation.


Assuntos
Receptores ErbB/genética , Hepatectomia , Regeneração Hepática/genética , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Obesidade/metabolismo , Animais , Apoptose/genética , Western Blotting , Dieta Hiperlipídica , Perfilação da Expressão Gênica , Fígado/patologia , Fígado/cirurgia , Camundongos , Camundongos Endogâmicos C57BL , Mitose/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Taxa de Sobrevida
16.
Ann Surg ; 265(1): 111-115, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28009734

RESUMO

OBJECTIVE: To determine the academic contribution as measured by number of publications, citations, and National Institutes of Health (NIH) funding from PhD scientists in US departments of surgery. SUMMARY BACKGROUND DATA: The number of PhD faculty working in US medical school clinical departments now exceeds the number working in basic science departments. The academic impact of PhDs in surgery has not been previously evaluated. METHODS: Academic metrics for 3850 faculties at the top 55 NIH-funded university and hospital-based departments of surgery were collected using NIH RePORTER, Scopus, and departmental websites. RESULTS: MD/PhDs and PhDs had significantly higher numbers of publications and citations than MDs, regardless of academic or institutional rank. PhDs had the greatest proportion of NIH funding compared to both MDs and MD/PhDs. Across all academic ranks, 50.2% of PhDs had received NIH funding compared with 15.2% of MDs and 33.9% of MD/PhDs (P < 0.001). The proportion of PhDs with NIH funding in the top 10 departments did not differ from those working in departments ranked 11 to 50 (P = 0.456). A greater percentage of departmental PhD faculty was associated with increased rates of MD funding. CONCLUSIONS: The presence of dedicated research faculty with PhDs supports the academic mission of surgery departments by increasing both NIH funding and scholarly productivity. In contrast to MDs and MD/PhDs, PhDs seem to have similar levels of academic output and funding independent of the overall NIH funding environment of their department. This suggests that research programs in departments with limited resources may be enhanced by the recruitment of PhD faculty.


Assuntos
Pesquisa Biomédica/estatística & dados numéricos , Docentes de Medicina/estatística & dados numéricos , Papel Profissional , Editoração/estatística & dados numéricos , Apoio à Pesquisa como Assunto/estatística & dados numéricos , Cirurgiões/estatística & dados numéricos , Pesquisa Biomédica/economia , Estudos Transversais , Docentes de Medicina/economia , Docentes de Medicina/educação , Hospitais Universitários , Humanos , National Institutes of Health (U.S.) , Editoração/economia , Apoio à Pesquisa como Assunto/economia , Estudos Retrospectivos , Faculdades de Medicina , Especialidades Cirúrgicas/economia , Especialidades Cirúrgicas/educação , Cirurgiões/economia , Cirurgiões/educação , Centro Cirúrgico Hospitalar , Estados Unidos
17.
Basic Res Cardiol ; 112(4): 48, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28647906

RESUMO

Growth differentiation factor 11 (GDF11), a TGF-beta superfamily member, is highly homologous to myostatin and essential for embryonic patterning and organogenesis. Reports of GDF11 effects on adult tissues are conflicting, with some describing anti-aging and pro-regenerative activities on the heart and skeletal muscle while others opposite or no effects. Herein, we sought to determine the in vivo cardiac and skeletal muscle effects of excess GDF11. Mice were injected with GDF11 secreting cells, an identical model to that used to initially identify the in vivo effects of myostatin. GDF11 exposure in mice induced whole body wasting and profound loss of function in cardiac and skeletal muscle over a 14-day period. Loss of cardiac mass preceded skeletal muscle loss. Cardiac histologic and echocardiographic evaluation demonstrated loss of ventricular muscle wall thickness, decreased cardiomyocyte size, and decreased cardiac function 10 days following initiation of GDF11 exposure. Changes in skeletal muscle after GDF11 exposure were manifest at day 13 and were associated with wasting, decreased fiber size, and reduced strength. Changes in cardiomyocytes and skeletal muscle fibers were associated with activation of SMAD2, the ubiquitin-proteasome pathway and autophagy. Thus, GDF11 over administration in vivo results in cardiac and skeletal muscle loss, dysfunction, and death. Here, serum levels of GDF11 by Western blotting were 1.5-fold increased over controls. Although GDF11 effects in vivo are likely dose, route, and duration dependent, its physiologic changes are similar to myostatin and other Activin receptors ligands. These data support that GDF11, like its other closely related TGF-beta family members, induces loss of cardiac and skeletal muscle mass and function.


Assuntos
Proteínas Morfogenéticas Ósseas/farmacologia , Caquexia/induzido quimicamente , Fatores de Diferenciação de Crescimento/farmacologia , Coração/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Miocárdio/patologia , Animais , Masculino , Camundongos , Camundongos Nus
18.
Curr Osteoporos Rep ; 15(2): 76-87, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28497213

RESUMO

PURPOSE OF REVIEW: In this article, we will discuss the current understanding of bone pain and muscle weakness in cancer patients. We will describe the underlying physiology and mechanisms of cancer-induced bone pain (CIBP) and cancer-induced muscle wasting (CIMW), as well as current methods of diagnosis and treatment. We will discuss future therapies and research directions to help patients with these problems. RECENT FINDINGS: There are several pharmacologic therapies that are currently in preclinical and clinical testing that appear to be promising adjuncts to current CIBP and CIMW therapies. Such therapies include resiniferitoxin, which is a targeted inhibitor of noceciptive nerve fibers, and selective androgen receptor modulators, which show promise in increasing lean mass. CIBP and CIMW are significant causes of morbidity in affected patients. Current management is mostly palliative; however, targeted therapies are poised to revolutionize how these problems are treated.


Assuntos
Doenças Ósseas/etiologia , Neoplasias Ósseas/secundário , Caquexia/etiologia , Dor do Câncer/etiologia , Debilidade Muscular/etiologia , Neoplasias/complicações , Sarcopenia/etiologia , Doenças Ósseas/fisiopatologia , Osso e Ossos , Caquexia/fisiopatologia , Dor do Câncer/fisiopatologia , Humanos , Hipercalcemia/etiologia , Debilidade Muscular/fisiopatologia , Sarcopenia/fisiopatologia
19.
Ann Vasc Surg ; 39: 242-249, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27671458

RESUMO

BACKGROUND: Changing training paradigms in vascular surgery have been introduced to reduce overall training time. Herein, we sought to examine how shortened training for vascular surgeons may have influenced overall divisional academic productivity. METHODS: Faculty from the top 55 surgery departments were identified according to National Institutes of Health (NIH) funding. Academic metrics of 315 vascular surgery, 1,132 general surgery, and 2,403 other surgical specialties faculty were examined using institutional Web sites, Scopus, and NIH Research Portfolio Online Reporting Tools from September 1, 2014, to January 31, 2015. Individual-level and aggregate numbers of publications, citations, and NIH funding were determined. RESULTS: The mean size of the vascular divisions was 5 faculty. There was no correlation between department size and academic productivity of individual faculty members (R2 = 0.68, P = 0.2). Overall percentage of vascular surgery faculty with current or former NIH funding was 20%, of which 10.8% had major NIH grants (R01/U01/P01). Vascular surgery faculty associated with integrated vascular training programs demonstrated significantly greater academic productivity. Publications and citations were higher for vascular surgery faculty from institutions with both integrated and traditional training programs (48 of 1,051) compared to those from programs with integrated training alone (37 of 485) or traditional fellowships alone (26 of 439; P < 0.05). CONCLUSIONS: In this retrospective examination, academic productivity was improved within vascular surgery divisions with integrated training programs or both program types. These data suggest that the earlier specialization of integrated residencies in addition to increasing dedicated vascular training time may actually help promote research within the field of vascular surgery.


Assuntos
Centros Médicos Acadêmicos , Pesquisa Biomédica/métodos , Educação de Pós-Graduação em Medicina/métodos , Eficiência , Docentes de Medicina , Internato e Residência , Cirurgiões/educação , Procedimentos Cirúrgicos Vasculares/educação , Autoria , Escolha da Profissão , Currículo , Humanos , Publicações Periódicas como Assunto , Avaliação de Programas e Projetos de Saúde , Estudos Retrospectivos , Especialização , Fatores de Tempo , Recursos Humanos
20.
Am J Physiol Endocrinol Metab ; 311(2): E436-48, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27382037

RESUMO

Burn trauma results in prolonged hypermetabolism and skeletal muscle wasting. How hypermetabolism contributes to muscle wasting in burn patients remains unknown. We hypothesized that oxidative stress, cytosolic protein degradation, and mitochondrial stress as a result of hypermetabolism contribute to muscle cachexia postburn. Patients (n = 14) with burns covering >30% of their total body surface area were studied. Controls (n = 13) were young healthy adults. We found that burn patients were profoundly hypermetabolic at both the skeletal muscle and systemic levels, indicating increased oxygen consumption by mitochondria. In skeletal muscle of burn patients, concurrent activation of mTORC1 signaling and elevation in the fractional synthetic rate paralleled increased levels of proteasomes and elevated fractional breakdown rate. Burn patients had greater levels of oxidative stress markers as well as higher expression of mtUPR-related genes and proteins, suggesting that burns increased mitochondrial stress and protein damage. Indeed, upregulation of cytoprotective genes suggests hypermetabolism-induced oxidative stress postburn. In parallel to mtUPR activation postburn, mitochondrial-specific proteases (LONP1 and CLPP) and mitochondrial translocases (TIM23, TIM17B, and TOM40) were upregulated, suggesting increased mitochondrial protein degradation and transport of preprotein, respectively. Our data demonstrate that proteolysis occurs in both the cytosolic and mitochondrial compartments of skeletal muscle in severely burned patients. Increased mitochondrial protein turnover may be associated with increased protein damage due to hypermetabolism-induced oxidative stress and activation of mtUPR. Our results suggest a novel role for the mitochondria in burn-induced cachexia.


Assuntos
Queimaduras/metabolismo , Caquexia/metabolismo , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Estresse Oxidativo , Consumo de Oxigênio , RNA Mensageiro/metabolismo , Proteases Dependentes de ATP/genética , Proteases Dependentes de ATP/metabolismo , Adolescente , Adulto , Western Blotting , Superfície Corporal , Queimaduras/complicações , Queimaduras/genética , Caquexia/etiologia , Caquexia/genética , Estudos de Casos e Controles , Endopeptidase Clp/genética , Endopeptidase Clp/metabolismo , Feminino , Humanos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Metabolismo , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Proteínas Musculares/metabolismo , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Reação em Cadeia da Polimerase em Tempo Real , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Regulação para Cima , Adulto Jovem
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