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1.
Cardiovasc Res ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38838211

RESUMO

AIMS: Although the cannabinoid CB1 receptor has been implicated in atherosclerosis, its cell-specific effects in this disease are not well understood. To address this, we generated a transgenic mouse model to study the role of myeloid CB1 signaling in atherosclerosis. METHODS AND RESULTS: Here, we report that male mice with myeloid-specific Cnr1 deficiency on atherogenic background developed smaller lesions and necrotic cores than controls, while only minor genotype differences were observed in females. Male Cnr1 deficient mice showed reduced arterial monocyte recruitment and macrophage proliferation with less inflammatory phenotype. The sex-specific differences in proliferation were dependent on estrogen receptor (ER)α-estradiol signaling. Kinase activity profiling identified a CB1-dependent regulation of p53 and cyclin-dependent kinases. Transcriptomic profiling further revealed chromatin modifications, mRNA processing and mitochondrial respiration among the key processes affected by CB1 signaling, which was supported by metabolic flux assays. Chronic administration of the peripherally-restricted CB1 antagonist JD5037 inhibited plaque progression and macrophage proliferation, but only in male mice. Finally, CNR1 expression was detectable in human carotid endarterectomy plaques and inversely correlated with proliferation, oxidative metabolism and inflammatory markers, suggesting a possible implication of CB1-dependent regulation in human pathophysiology. CONCLUSION: Impaired macrophage CB1 signaling is atheroprotective by limiting their arterial recruitment, proliferation and inflammatory reprogramming in male mice. The importance of macrophage CB1 signaling appears to be sex-dependent.

2.
Nat Methods ; 21(7): 1306-1315, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38649742

RESUMO

Automated detection of specific cells in three-dimensional datasets such as whole-brain light-sheet image stacks is challenging. Here, we present DELiVR, a virtual reality-trained deep-learning pipeline for detecting c-Fos+ cells as markers for neuronal activity in cleared mouse brains. Virtual reality annotation substantially accelerated training data generation, enabling DELiVR to outperform state-of-the-art cell-segmenting approaches. Our pipeline is available in a user-friendly Docker container that runs with a standalone Fiji plugin. DELiVR features a comprehensive toolkit for data visualization and can be customized to other cell types of interest, as we did here for microglia somata, using Fiji for dataset-specific training. We applied DELiVR to investigate cancer-related brain activity, unveiling an activation pattern that distinguishes weight-stable cancer from cancers associated with weight loss. Overall, DELiVR is a robust deep-learning tool that does not require advanced coding skills to analyze whole-brain imaging data in health and disease.


Assuntos
Encéfalo , Aprendizado Profundo , Realidade Virtual , Animais , Encéfalo/diagnóstico por imagem , Camundongos , Neurônios , Software , Processamento de Imagem Assistida por Computador/métodos , Proteínas Proto-Oncogênicas c-fos/metabolismo , Humanos
3.
Cardiovasc Diabetol ; 23(1): 104, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504284

RESUMO

The 9th Cardiovascular Outcome Trial (CVOT) Summit: Congress on Cardiovascular, Kidney, and Metabolic Outcomes was held virtually on November 30-December 1, 2023. This reference congress served as a platform for in-depth discussions and exchange on recently completed outcomes trials including dapagliflozin (DAPA-MI), semaglutide (SELECT and STEP-HFpEF) and bempedoic acid (CLEAR Outcomes), and the advances they represent in reducing the risk of major adverse cardiovascular events (MACE), improving metabolic outcomes, and treating obesity-related heart failure with preserved ejection fraction (HFpEF). A broad audience of endocrinologists, diabetologists, cardiologists, nephrologists and primary care physicians participated in online discussions on guideline updates for the management of cardiovascular disease (CVD) in diabetes, heart failure (HF) and chronic kidney disease (CKD); advances in the management of type 1 diabetes (T1D) and its comorbidities; advances in the management of CKD with SGLT2 inhibitors and non-steroidal mineralocorticoid receptor antagonists (nsMRAs); and advances in the treatment of obesity with GLP-1 and dual GIP/GLP-1 receptor agonists. The association of diabetes and obesity with nonalcoholic steatohepatitis (NASH; metabolic dysfunction-associated steatohepatitis, MASH) and cancer and possible treatments for these complications were also explored. It is generally assumed that treatment of chronic diseases is equally effective for all patients. However, as discussed at the Summit, this assumption may not be true. Therefore, it is important to enroll patients from diverse racial and ethnic groups in clinical trials and to analyze patient-reported outcomes to assess treatment efficacy, and to develop innovative approaches to tailor medications to those who benefit most with minimal side effects. Other keys to a successful management of diabetes and comorbidities, including dementia, entail the use of continuous glucose monitoring (CGM) technology and the implementation of appropriate patient-physician communication strategies. The 10th Cardiovascular Outcome Trial Summit will be held virtually on December 5-6, 2024 ( http://www.cvot.org ).


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Diabetes Mellitus , Insuficiência Cardíaca , Insuficiência Renal Crônica , Humanos , Insuficiência Cardíaca/complicações , Automonitorização da Glicemia , Volume Sistólico , Glicemia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Obesidade/complicações , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/terapia , Diabetes Mellitus/tratamento farmacológico , Rim , Diabetes Mellitus Tipo 2/tratamento farmacológico
4.
Nat Commun ; 15(1): 1391, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360943

RESUMO

In obesity, sustained adipose tissue (AT) inflammation constitutes a cellular memory that limits the effectiveness of weight loss interventions. Yet, the impact of fasting regimens on the regulation of AT immune infiltration is still elusive. Here we show that intermittent fasting (IF) exacerbates the lipid-associated macrophage (LAM) inflammatory phenotype of visceral AT in obese mice. Importantly, this increase in LAM abundance is strongly p53 dependent and partly mediated by p53-driven adipocyte apoptosis. Adipocyte-specific deletion of p53 prevents LAM accumulation during IF, increases the catabolic state of adipocytes, and enhances systemic metabolic flexibility and insulin sensitivity. Finally, in cohorts of obese/diabetic patients, we describe a p53 polymorphism that links to efficacy of a fasting-mimicking diet and that the expression of p53 and TREM2 in AT negatively correlates with maintaining weight loss after bariatric surgery. Overall, our results demonstrate that p53 signalling in adipocytes dictates LAM accumulation in AT under IF and modulates fasting effectiveness in mice and humans.


Assuntos
Resistência à Insulina , Jejum Intermitente , Proteína Supressora de Tumor p53 , Animais , Humanos , Camundongos , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Inflamação/metabolismo , Resistência à Insulina/genética , Obesidade/genética , Obesidade/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Redução de Peso
5.
Biochem J ; 481(1): 33-44, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38112318

RESUMO

Advanced glycation end products (AGEs) are non-enzymatic post-translational modifications of amino acids and are associated with diabetic complications. One proposed pathomechanism is the impaired processing of AGE-modified proteins or peptides including prohormones. Two approaches were applied to investigate whether substrate modification with AGEs affects the processing of substrates like prohormones to the active hormones. First, we employed solid-phase peptide synthesis to generate unmodified as well as AGE-modified protease substrates. Activity of proteases towards these substrates was quantified. Second, we tested the effect of AGE-modified proinsulin on the processing to insulin. Proteases showed the expected activity towards the unmodified peptide substrates containing arginine or lysine at the C-terminal cleavage site. Indeed, modification with Nε-carboxymethyllysine (CML) or methylglyoxal-hydroimidazolone 1 (MG-H1) affected all proteases tested. Cysteine cathepsins displayed a reduction in activity by ∼50% towards CML and MG-H1 modified substrates. The specific proteases trypsin, proprotein convertases subtilisin-kexins (PCSKs) type proteases, and carboxypeptidase E (CPE) were completely inactive towards modified substrates. Proinsulin incubation with methylglyoxal at physiological concentrations for 24 h resulted in the formation of MG-modified proinsulin. The formation of insulin was reduced by up to 80% in a concentration-dependent manner. Here, we demonstrate the inhibitory effect of substrate-AGE modifications on proteases. The finding that PCSKs and CPE, which are essential for prohormone processing, are inactive towards modified substrates could point to a yet unrecognized pathomechanism resulting from AGE modification relevant for the etiopathogenesis of diabetes and the development of obesity.


Assuntos
Diabetes Mellitus , Produtos Finais de Glicação Avançada , Humanos , Aldeído Pirúvico/metabolismo , Proinsulina , Peptídeos/química , Endopeptidases
6.
EMBO Rep ; 24(10): e57600, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37671834

RESUMO

Adipocytes are critical regulators of metabolism and energy balance. While white adipocyte dysfunction is a hallmark of obesity-associated disorders, thermogenic adipocytes are linked to cardiometabolic health. As adipocytes dynamically adapt to environmental cues by functionally switching between white and thermogenic phenotypes, a molecular understanding of this plasticity could help improving metabolism. Here, we show that the lncRNA Apoptosis associated transcript in bladder cancer (AATBC) is a human-specific regulator of adipocyte plasticity. Comparing transcriptional profiles of human adipose tissues and cultured adipocytes we discovered that AATBC was enriched in thermogenic conditions. Using primary and immortalized human adipocytes we found that AATBC enhanced the thermogenic phenotype, which was linked to increased respiration and a more fragmented mitochondrial network. Expression of AATBC in adipose tissue of mice led to lower plasma leptin levels. Interestingly, this association was also present in human subjects, as AATBC in adipose tissue was inversely correlated with plasma leptin levels, BMI, and other measures of metabolic health. In conclusion, AATBC is a novel obesity-linked regulator of adipocyte plasticity and mitochondrial function in humans.

7.
Nat Cancer ; 4(11): 1544-1560, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37749321

RESUMO

Cachexia is a major cause of morbidity and mortality in individuals with cancer and is characterized by weight loss due to adipose and muscle tissue wasting. Hallmarks of white adipose tissue (WAT) remodeling, which often precedes weight loss, are impaired lipid storage, inflammation and eventually fibrosis. Tissue wasting occurs in response to tumor-secreted factors. Considering that the continuous endothelium in WAT is the first line of contact with circulating factors, we postulated whether the endothelium itself may orchestrate tissue remodeling. Here, we show using human and mouse cancer models that during precachexia, tumors overactivate Notch1 signaling in distant WAT endothelium. Sustained endothelial Notch1 signaling induces a WAT wasting phenotype in male mice through excessive retinoic acid production. Pharmacological blockade of retinoic acid signaling was sufficient to inhibit WAT wasting in a mouse cancer cachexia model. This demonstrates that cancer manipulates the endothelium at distant sites to mediate WAT wasting by altering angiocrine signals.


Assuntos
Tecido Adiposo Branco , Caquexia , Neoplasias , Receptor Notch1 , Animais , Humanos , Masculino , Camundongos , Tecido Adiposo Branco/patologia , Caquexia/patologia , Neoplasias/complicações , Transdução de Sinais , Tretinoína , Receptor Notch1/metabolismo
8.
Mol Ther ; 31(8): 2408-2421, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37408309

RESUMO

Cancer cachexia is a severe systemic wasting disease that negatively affects quality of life and survival in patients with cancer. To date, treating cancer cachexia is still a major unmet clinical need. We recently discovered the destabilization of the AMP-activated protein kinase (AMPK) complex in adipose tissue as a key event in cachexia-related adipose tissue dysfunction and developed an adeno-associated virus (AAV)-based approach to prevent AMPK degradation and prolong cachexia-free survival. Here, we show the development and optimization of a prototypic peptide, Pen-X-ACIP, where the AMPK-stabilizing peptide ACIP is fused to the cell-penetrating peptide moiety penetratin via a propargylic glycine linker to enable late-stage functionalization using click chemistry. Pen-X-ACIP was efficiently taken up by adipocytes, inhibited lipolysis, and restored AMPK signaling. Tissue uptake assays showed a favorable uptake profile into adipose tissue upon intraperitoneal injection. Systemic delivery of Pen-X-ACIP into tumor-bearing animals prevented the progression of cancer cachexia without affecting tumor growth and preserved body weight and adipose tissue mass with no discernable side effects in other peripheral organs, thereby achieving proof of concept. As Pen-X-ACIP also exerted its anti-lipolytic activity in human adipocytes, it now provides a promising platform for further (pre)clinical development toward a novel, first-in-class approach against cancer cachexia.


Assuntos
Proteínas Quinases Ativadas por AMP , Neoplasias , Animais , Humanos , Tecido Adiposo/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Caquexia/tratamento farmacológico , Caquexia/etiologia , Caquexia/metabolismo , Neoplasias/complicações , Neoplasias/metabolismo , Peptídeos/farmacologia , Preparações Farmacêuticas/metabolismo , Qualidade de Vida
9.
Sci Adv ; 8(42): eabo5555, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36269831

RESUMO

Maladaptive insulin signaling is a key feature in the pathogenesis of severe metabolic disorders, including obesity and diabetes. Enhancing insulin sensitivity represents a major goal in the treatment of patients affected by diabetes. Here, we identify transforming growth factor-ß1 stimulated clone 22 D4 (TSC22D4) as a novel interaction partner for protein kinase B/Akt1, a critical mediator of insulin/phosphatidylinositol 3-kinase signaling pathway. While energy deprivation and oxidative stress promote the TSC22D4-Akt1 interaction, refeeding mice or exposing cells to glucose and insulin impairs this interaction, which relies on an intrinsically disordered region (D2 domain) within TSC22D4. Functionally, the interaction with TSC22D4 reduces basal phosphorylation of Akt and its downstream targets during starvation, thereby promoting insulin sensitivity. Genetic, liver-specific reconstitution experiments in mice demonstrate that the interaction between TSC22D4 and Akt1 improves glucose handling and insulin sensitivity. Overall, our findings postulate a model whereby TSC22D4 acts as an environmental sensor and interacts with Akt1 to regulate insulin signaling and glucose metabolism.


Assuntos
Resistência à Insulina , Proteínas Proto-Oncogênicas c-akt , Animais , Camundongos , Glucose/metabolismo , Insulina/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores de Transcrição , Fator de Crescimento Transformador beta1
10.
Cancer Metastasis Rev ; 41(3): 517-547, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36074318

RESUMO

Obesity is an established risk factor for several human cancers. Given the association between excess body weight and cancer, the increasing rates of obesity worldwide are worrisome. A variety of obesity-related factors has been implicated in cancer initiation, progression, and response to therapy. These factors include circulating nutritional factors, hormones, and cytokines, causing hyperinsulinemia, inflammation, and adipose tissue dysfunction. The impact of these conditions on cancer development and progression has been the focus of extensive literature. In this review, we concentrate on processes that can link obesity and cancer, and which provide a novel perspective: extracellular matrix remodeling, angiogenesis, and adrenergic signaling. We describe molecular mechanisms involved in these processes, which represent putative targets for intervention. Liver, pancreas, and breast cancers were chosen as exemplary disease models. In view of the expanding epidemic of obesity, a better understanding of the tumorigenic process in obese individuals might lead to more effective treatments and preventive measures.


Assuntos
Adrenérgicos , Neoplasias , Tecido Adiposo , Matriz Extracelular , Humanos , Neoplasias/epidemiologia , Obesidade/complicações
11.
Adv Sci (Weinh) ; 9(29): e2104291, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36031387

RESUMO

Aberrant energy metabolism and cell cycle regulation both critically contribute to malignant cell growth and both processes represent targets for anticancer therapy. It is shown here that depletion of the AAA+-ATPase thyroid hormone receptor interacting protein 13 (Trip13) results in mitotic cell death through a combined mechanism linking lipid metabolism to aberrant mitosis. Diminished Trip13 levels in hepatocellular carcinoma cells result in insulin-receptor-/Akt-pathway-dependent accumulation of lipid droplets, which act as functional acentriolar microtubule organizing centers disturbing mitotic spindle polarity. Specifically, the lipid-droplet-coating protein perilipin 2 (Plin2) is required for multipolar spindle formation, induction of DNA damage, and mitotic cell death. Plin2 expression in different tumor cells confers susceptibility to cell death induced by Trip13 depletion as well as treatment with paclitaxel, a spindle-interfering drug commonly used against different cancers. Thus, assessment of Plin2 levels enables the stratification of tumor responsiveness to mitosis-targeting drugs, including clinically approved paclitaxel and Trip13 inhibitors currently under development.


Assuntos
Insulinas , Neoplasias Hepáticas , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Proteínas de Ciclo Celular/metabolismo , Morte Celular , Humanos , Insulinas/metabolismo , Lipídeos , Proteínas Mad2/metabolismo , Paclitaxel/farmacologia , Perilipina-2 , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores dos Hormônios Tireóideos/metabolismo
12.
EMBO Mol Med ; 14(5): e14364, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35266635

RESUMO

Invasive nonfunctioning (NF) pituitary neuroendocrine tumors (PitNETs) are non-resectable neoplasms associated with frequent relapses and significant comorbidities. As the current therapies of NF-PitNETs often fail, new therapeutic targets are needed. The observation that circulating angiopoietin-2 (ANGPT2) is elevated in patients with NF-PitNET and correlates with tumor aggressiveness prompted us to investigate the ANGPT2/TIE2 axis in NF-PitNETs in the GH3 PitNET cell line, primary human NF-PitNET cells, xenografts in zebrafish and mice, and in MENX rats, the only autochthonous NF-PitNET model. We show that PitNET cells express a functional TIE2 receptor and secrete bioactive ANGPT2, which promotes, besides angiogenesis, tumor cell growth in an autocrine and paracrine fashion. ANGPT2 stimulation of TIE2 in tumor cells activates downstream cell proliferation signals, as previously demonstrated in endothelial cells (ECs). Tie2 gene deletion blunts PitNETs growth in xenograft models, and pharmacological inhibition of Angpt2/Tie2 signaling antagonizes PitNETs in primary cell cultures, tumor xenografts in mice, and in MENX rats. Thus, the ANGPT2/TIE2 axis provides an exploitable therapeutic target in NF-PitNETs and possibly in other tumors expressing ANGPT2/TIE2. The ability of tumor cells to coopt angiogenic signals classically viewed as EC-specific expands our view on the microenvironmental cues that are essential for tumor progression.


Assuntos
Angiopoietina-2 , Neoplasias Hipofisárias , Angiopoietina-2/metabolismo , Animais , Carcinogênese , Células Endoteliais/metabolismo , Xenoenxertos , Humanos , Camundongos , Recidiva Local de Neoplasia , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia , Ratos , Receptor TIE-2/genética , Receptor TIE-2/metabolismo , Peixe-Zebra
13.
Cell Metab ; 34(3): 473-486.e9, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35120589

RESUMO

Fasting metabolism and immunity are tightly linked; however, it is largely unknown how immune cells contribute to metabolic homeostasis during fasting in healthy subjects. Here, we combined cell-type-resolved genomics and computational approaches to map crosstalk between hepatocytes and liver macrophages during fasting. We identified the glucocorticoid receptor (GR) as a key driver of fasting-induced reprogramming of the macrophage secretome including fasting-suppressed cytokines and showed that lack of macrophage GR impaired induction of ketogenesis during fasting as well as endotoxemia. Mechanistically, macrophage GR suppressed the expression of tumor necrosis factor (TNF) and promoted nuclear translocation of hepatocyte GR to activate a fat oxidation/ketogenesis-related gene program, cooperatively induced by GR and peroxisome proliferator-activated receptor alpha (PPARα) in hepatocytes. Together, our results demonstrate how resident liver macrophages directly influence ketogenesis in hepatocytes, thereby also outlining a strategy by which the immune system can set the metabolic tone during inflammatory disease and infection.


Assuntos
Jejum , Receptores de Glucocorticoides , Animais , Jejum/metabolismo , Hepatócitos/metabolismo , Humanos , Corpos Cetônicos/metabolismo , Fígado/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , PPAR alfa/metabolismo , Receptores de Glucocorticoides/metabolismo
14.
Cell Rep Med ; 2(11): 100434, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34841287

RESUMO

miRNAs have crucial functions in many biological processes and are candidate biomarkers of disease. Here, we show that miR-216a is a conserved, pancreas-specific miRNA with important roles in pancreatic islet and acinar cells. Deletion of miR-216a in mice leads to a reduction in islet size, ß-cell mass, and insulin levels. Single-cell RNA sequencing reveals a subpopulation of ß-cells with upregulated acinar cell markers under a high-fat diet. miR-216a is induced by TGF-ß signaling, and inhibition of miR-216a increases apoptosis and decreases cell proliferation in pancreatic cells. Deletion of miR-216a in the pancreatic cancer-prone mouse line KrasG12D;Ptf1aCreER reduces the propensity of pancreatic cancer precursor lesions. Notably, circulating miR-216a levels are elevated in both mice and humans with pancreatic cancer. Collectively, our study gives insights into how ß-cell mass and acinar cell growth are modulated by a pancreas-specific miRNA and also suggests miR-216a as a potential biomarker for diagnosis of pancreatic diseases.


Assuntos
Progressão da Doença , Deleção de Genes , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , MicroRNAs/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Animais , Apoptose , Sequência de Bases , Linhagem Celular Tumoral , Movimento Celular , Dieta Hiperlipídica , Humanos , Secreção de Insulina , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/metabolismo , Especificidade de Órgãos , Ratos
15.
EJNMMI Res ; 11(1): 94, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34557972

RESUMO

Cachexia, a multifactorial wasting syndrome, is highly prevalent among advanced-stage cancer patients. Unlike weight loss in healthy humans, the progressive loss of body weight in cancer cachexia primarily implicates lean body mass, caused by an aberrant metabolism and systemic inflammation. This may lead to disease aggravation, poorer quality of life, and increased mortality. Timely detection is, therefore, crucial, as is the careful monitoring of cancer progression, in an effort to improve management, facilitate individual treatment and minimize disease complications. A detailed analysis of body composition and tissue changes using imaging modalities-that is, computed tomography, magnetic resonance imaging, (18F) fluoro-2-deoxy-D-glucose (18FDG) PET and dual-energy X-ray absorptiometry-shows great premise for charting the course of cachexia. Quantitative and qualitative changes to adipose tissue, organs, and muscle compartments, particularly of the trunk and extremities, could present important biomarkers for phenotyping cachexia and determining its onset in patients. In this review, we present and compare the imaging techniques that have been used in the setting of cancer cachexia. Their individual limitations, drawbacks in the face of clinical routine care, and relevance in oncology are also discussed.

16.
Cancers (Basel) ; 13(17)2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34503243

RESUMO

PURPOSE: To evaluate the suitability of psoas and erector spinae muscle proton density fat fraction (PDFF) and fat volume as biomarkers for monitoring cachexia severity in an oncological cohort, and to evaluate regional variances in muscle parameters over time. METHODS: In this prospective study, 58 oncological patients were examined by a 3 T MRI receiving between one and five scans. Muscle volume and PDFF were measured, segmentation masks were divided into proximal, middle and distal muscle section. RESULTS: A regional variation of fat distribution in erector spinae muscle at baseline was found (p < 0.01). During follow-ups significant relative change of muscle parameters was observed. Relative maximum change of erector spinae muscle showed a significant regional variation. Correlation testing with age as a covariate revealed significant correlations for baseline psoas fat volume (r = -0.55, p < 0.01) and baseline psoas PDFF (r = -0.52, p = 0.02) with maximum BMI change during the course of the disease. CONCLUSION: In erector spinae muscles, a regional variation of fat distribution at baseline and relative maximum change of muscle parameters was observed. Our results indicate that psoas muscle PDFF and fat volume could serve as MRI-determined biomarkers for early risk stratification and disease monitoring regarding progression and severity of weight loss in cancer cachexia.

17.
J Cachexia Sarcopenia Muscle ; 12(5): 1333-1351, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34427055

RESUMO

BACKGROUND: Cancer cachexia (CCx) is a multifactorial wasting disorder characterized by involuntary loss of body weight that affects many cancer patients and implies a poor prognosis, reducing both tolerance to and efficiency of anticancer therapies. Actual challenges in management of CCx remain in the identification of tumour-derived and host-derived mediators involved in systemic inflammation and tissue wasting and in the discovery of biomarkers that would allow for an earlier and personalized care of cancer patients. The aim of this study was to identify new markers of CCx across different species and tumour entities. METHODS: Quantitative secretome analysis was performed to identify specific factors characteristic of cachexia-inducing cancer cell lines. To establish the subsequently identified phospholipase PLA2G7 as a marker of CCx, plasma PLA2G7 activity and/or protein levels were measured in well-established mouse models of CCx and in different cohorts of weight-stable and weight-losing cancer patients with different tumour entities. Genetic PLA2G7 knock-down in tumours and pharmacological treatment using the well-studied PLA2G7 inhibitor darapladib were performed to assess its implication in the pathogenesis of CCx in C26 tumour-bearing mice. RESULTS: High expression and secretion of PLA2G7 were hallmarks of cachexia-inducing cancer cell lines. Circulating PLA2G7 activity was increased in different mouse models of CCx with various tumour entities and was associated with the severity of body wasting. Circulating PLA2G7 levels gradually rose during cachexia development. Genetic PLA2G7 knock-down in C26 tumours only partially reduced plasma PLA2G7 levels, suggesting that the host is also an important contributor. Chronic treatment with darapladib was not sufficient to counteract inflammation and tissue wasting despite a strong inhibition of the circulating PLA2G7 activity. Importantly, PLA2G7 levels were also increased in colorectal and pancreatic cancer patients with CCx. CONCLUSIONS: Overall, our data show that despite no immediate pathogenic role, at least when targeted as a single entity, PLA2G7 is a consistent marker of CCx in both mice and humans. The early increase in circulating PLA2G7 levels in pre-cachectic mice supports future prospective studies to assess its potential as biomarker for cancer patients.


Assuntos
Caquexia , Neoplasias Pancreáticas , 1-Alquil-2-acetilglicerofosfocolina Esterase , Animais , Benzaldeídos , Biomarcadores , Caquexia/tratamento farmacológico , Caquexia/etiologia , Humanos , Camundongos , Oximas , Estudos Prospectivos
18.
Nat Commun ; 12(1): 5068, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34417460

RESUMO

p53 regulates several signaling pathways to maintain the metabolic homeostasis of cells and modulates the cellular response to stress. Deficiency or excess of nutrients causes cellular metabolic stress, and we hypothesized that p53 could be linked to glucose maintenance. We show here that upon starvation hepatic p53 is stabilized by O-GlcNAcylation and plays an essential role in the physiological regulation of glucose homeostasis. More specifically, p53 binds to PCK1 promoter and regulates its transcriptional activation, thereby controlling hepatic glucose production. Mice lacking p53 in the liver show a reduced gluconeogenic response during calorie restriction. Glucagon, adrenaline and glucocorticoids augment protein levels of p53, and administration of these hormones to p53 deficient human hepatocytes and to liver-specific p53 deficient mice fails to increase glucose levels. Moreover, insulin decreases p53 levels, and over-expression of p53 impairs insulin sensitivity. Finally, protein levels of p53, as well as genes responsible of O-GlcNAcylation are elevated in the liver of type 2 diabetic patients and positively correlate with glucose and HOMA-IR. Overall these results indicate that the O-GlcNAcylation of p53 plays an unsuspected key role regulating in vivo glucose homeostasis.


Assuntos
Acetilglucosamina/metabolismo , Glucose/metabolismo , Fígado/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Sequência de Bases , Restrição Calórica , Linhagem Celular , Colforsina/farmacologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Epinefrina/metabolismo , Glucagon/metabolismo , Glucocorticoides/metabolismo , Gluconeogênese/efeitos dos fármacos , Glicosilação , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Hidrocortisona/metabolismo , Hiperglicemia/complicações , Hiperglicemia/metabolismo , Resistência à Insulina , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fígado/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/complicações , Obesidade/metabolismo , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Ácido Pirúvico/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Gênica/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética
19.
Cancers (Basel) ; 13(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200336

RESUMO

Small cell lung carcinoma (SCLC) is a highly aggressive malignancy with a very high mortality rate. A prominent part of this is because these carcinomas are refractory to chemotherapies, such as etoposide or cisplatin, making effective treatment almost impossible. Here, we report that elevated expression of the RAGE variant-V in SCLC promotes homology-directed DNA DSBs repair when challenged with anti-cancer drugs. This variant exclusively localizes to the nucleus, interacts with members of the double-strand break (DSB) repair machinery and thus promotes the recruitment of DSBs repair factors at the site of damage. Increased expression of this variant thus, promotes timely DNA repair. Congruently, the tumor cells expressing high levels of variant-V can tolerate chemotherapeutic drug treatment better than the RAGE depleted cells. Our findings reveal a yet undisclosed role of the RAGE variant-V in the homology-directed DNA repair. This variant thus can be a potential target to be considered for future therapeutic approaches in advanced SSLC.

20.
Nat Commun ; 12(1): 2999, 2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-34016966

RESUMO

The proper functional interaction between different tissues represents a key component in systemic metabolic control. Indeed, disruption of endocrine inter-tissue communication is a hallmark of severe metabolic dysfunction in obesity and diabetes. Here, we show that the FNDC4-GPR116, liver-white adipose tissue endocrine axis controls glucose homeostasis. We found that the liver primarily controlled the circulating levels of soluble FNDC4 (sFNDC4) and lowering of the hepatokine FNDC4 led to prediabetes in mice. Further, we identified the orphan adhesion GPCR GPR116 as a receptor of sFNDC4 in the white adipose tissue. Upon direct and high affinity binding of sFNDC4 to GPR116, sFNDC4 promoted insulin signaling and insulin-mediated glucose uptake in white adipocytes. Indeed, supplementation with FcsFNDC4 in prediabetic mice improved glucose tolerance and inflammatory markers in a white-adipocyte selective and GPR116-dependent manner. Of note, the sFNDC4-GPR116, liver-adipose tissue axis was dampened in (pre) diabetic human patients. Thus our findings will now allow for harnessing this endocrine circuit for alternative therapeutic strategies in obesity-related pre-diabetes.


Assuntos
Tecido Adiposo Branco/metabolismo , Proteínas de Membrana/metabolismo , Estado Pré-Diabético/metabolismo , Proteínas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Células 3T3-L1 , Adipócitos/metabolismo , Tecido Adiposo Branco/citologia , Adolescente , Adulto , Idoso , Animais , Células CHO , Estudos de Coortes , Cricetulus , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/prevenção & controle , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Feminino , Técnicas de Silenciamento de Genes , Glucose/metabolismo , Células HEK293 , Células Hep G2 , Humanos , Insulina/metabolismo , Resistência à Insulina , Ilhotas Pancreáticas/metabolismo , Fígado/metabolismo , Masculino , Proteínas de Membrana/administração & dosagem , Proteínas de Membrana/sangue , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Células NIH 3T3 , Estado Pré-Diabético/sangue , Estado Pré-Diabético/tratamento farmacológico , Estado Pré-Diabético/etiologia , Cultura Primária de Células , Proteínas/análise , Receptores Acoplados a Proteínas G/sangue , Receptores Acoplados a Proteínas G/genética , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Adulto Jovem
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