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2.
Artigo em Inglês | MEDLINE | ID: mdl-38364948

RESUMO

PURPOSE: Studies during the past 9 years suggest that delivering radiation at dose rates exceeding 40 Gy/s, known as "FLASH" radiation therapy, enhances the therapeutic index of radiation therapy (RT) by decreasing normal tissue damage while maintaining tumor response compared with conventional (or standard) RT. This study demonstrates the cardioprotective benefits of FLASH proton RT (F-PRT) compared with standard (conventional) proton RT (S-PRT), as evidenced by reduced acute and chronic cardiac toxicities. METHODS AND MATERIALS: Mice were imaged using cone beam computed tomography to precisely determine the heart's apex as the beam isocenter. Irradiation was conducted using a shoot-through technique with a 5-mm diameter circular collimator. Bulk RNA-sequencing was performed on nonirradiated samples, as well as apexes treated with F-PRT or S-PRT, at 2 weeks after a single 40 Gy dose. Inflammatory responses were assessed through multiplex cytokine/chemokine microbead assay and immunofluorescence analyses. Levels of perivascular fibrosis were quantified using Masson's Trichrome and Picrosirius red staining. Additionally, cardiac tissue functionality was evaluated by 2-dimensional echocardiograms at 8- and 30-weeks post-PRT. RESULTS: Radiation damage was specifically localized to the heart's apex. RNA profiling of cardiac tissues treated with PRT revealed that S-PRT uniquely upregulated pathways associated with DNA damage response, induction of tumor necrosis factor superfamily, and inflammatory response, and F-PRT primarily affected cytoplasmic translation, mitochondrion organization, and adenosine triphosphate synthesis. Notably, F-PRT led to a milder inflammatory response, accompanied by significantly attenuated changes in transforming growth factor ß1 and α smooth muscle actin levels. Critically, F-PRT decreased collagen deposition and better preserved cardiac functionality compared with S-PRT. CONCLUSIONS: This study demonstrated that F-PRT reduces the induction of an inflammatory environment with lower expression of inflammatory cytokines and profibrotic factors. Importantly, the results indicate that F-PRT better preserves cardiac functionality, as confirmed by echocardiography analysis, while also mitigating the development of long-term fibrosis.

3.
EClinicalMedicine ; 64: 102235, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37936659

RESUMO

Background: Type 2 diabetes disproportionately affects individuals of non-White ethnicity through a complex interaction of multiple factors. Therefore, early disease detection and prediction are essential and require tools that can be deployed on a large scale. We aimed to tackle this problem by developing questionnaire-based prediction models for type 2 diabetes prevalence and incidence for multiple ethnicities. Methods: In this proof of principle analysis, logistic regression models to predict type 2 diabetes prevalence and incidence, using questionnaire-only variables reflecting health state and lifestyle, were trained on the White population of the UK Biobank (n = 472,696 total, aged 37-73 years, data collected 2006-2010) and validated in five other ethnicities (n = 29,811 total) and externally in Lifelines (n = 168,205 total, aged 0-93 years, collected between 2006 and 2013). In total, 631,748 individuals were included for prevalence prediction and 67,083 individuals for the eight-year incidence prediction. Type 2 diabetes prevalence in the UK Biobank ranged between 6% in the White population to 23.3% in the South Asian population, while in Lifelines, the prevalence was 1.9%. Predictive accuracy was evaluated using the area under the receiver operating characteristic curve (AUC), and a detailed sensitivity analysis was conducted to assess potential clinical utility. We compared the questionnaire-only models to models containing physical measurements and biomarkers as well as to clinical non-laboratory type 2 diabetes risk tools and conducted a reclassification analysis. Findings: Our algorithms accurately predicted type 2 diabetes prevalence (AUC = 0.901) and eight-year incidence (AUC = 0.873) in the White UK Biobank population. Both models replicated well in the Lifelines external validation, with AUCs of 0.917 and 0.817 for prevalence and incidence, respectively. Both models performed consistently well across different ethnicities, with AUCs of 0.855-0.894 for prevalence and 0.819-0.883 for incidence. These models generally outperformed two clinically validated non-laboratory tools and correctly reclassified >3,000 additional cases. Model performance improved with the addition of blood biomarkers but not with the addition of physical measurements. Interpretation: Our findings suggest that easy-to-implement, questionnaire-based models could be used to predict prevalent and incident type 2 diabetes with high accuracy across several ethnicities, providing a highly scalable solution for population-wide risk stratification. Future work should determine the effectiveness of these models in identifying undiagnosed type 2 diabetes, validated in cohorts of different populations and ethnic representation. Funding: University Medical Center Groningen.

5.
Metabolism ; 148: 155689, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37689110

RESUMO

The 21st century is characterized by an increasing incidence and prevalence of obesity and the burden of its associated comorbidities, especially cardiometabolic diseases, which are reaching pandemic proportions. In the late '90s, the "black box" of adipose tissue and energy homeostasis was opened with the discovery of leptin, transforming the adipose tissue from an "inert fat-storage organ" to the largest human endocrine organ and creating the basis on which more intensified research efforts to elucidate the pathogenesis of obesity and develop novel treatments were based upon. Even though leptin was eventually not proven to be the "standalone magic bullet" for the treatment of common/polygenic obesity, it has been successful in the treatment of monogenic obesity syndromes. Additionally, it shifted the paradigm of treating obesity from a condition due to "lack of willpower" to a disease due to distinct underlying biological mechanisms for which specific pharmacotherapies would be needed in addition to lifestyle modification. Subsequently, the melanocortin pathway proved to be an equally valuable pathway for the pharmacotherapy of obesity. Melanocortin receptor agonists have recently been approved for treating certain types of syndromic obesity. Other molecules- such as incretins, implicated in energy and glucose homeostasis- are secreted by the gastrointestinal tract. Glucagon-like peptide 1 (GLP-1) is the most prominent one, with GLP-1 analogs approved for common/polygenic obesity. Unimolecular combinations with other incretins, e.g., GLP-1 with gastric inhibitory polypeptide and/or glucagon, are expected to be approved soon as more effective pharmacotherapies for obesity and its comorbidities. Unimolecular combinations with other compounds and small molecules activating the receptors of these molecules are currently under investigation as promising future pharmacotherapies. Moreover, metabolic and bariatric surgery has also demonstrated impressive results, especially in the case of morbid obesity. Consequently, this broadening therapeutic armamentarium calls for a well-thought-after and well-coordinated multidisciplinary approach, for instance, through cardiometabolic expertise centers, that would ideally address effectively and cost-effectively obesity and its comorbidities, providing tangible benefits to large segments of the population.

6.
Metabolism ; 147: 155666, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37527759

RESUMO

BACKGROUND: Non-invasive tools (NIT) for metabolic-dysfunction associated liver disease (MASLD) screening or diagnosis need to be thoroughly validated using liver biopsies. PURPOSE: To externally validate NITs designed to differentiate the presence or absence of liver steatosis as well as more advanced disease stages, to confirm fully validated indexes (n = 7 NITs), to fully validate partially validated indexes (n = 5 NITs), and to validate for the first time one new index (n = 1 NIT). METHODS: This is a multi-center study from two Gastroenterology-Hepatology Departments (Greece and Australia) and one Bariatric-Metabolic Surgery Department (Italy). Overall, n = 455 serum samples of patients with biopsy-proven MASLD (n = 374, including 237 patients with metabolic-dysfunction associated steatohepatitis (MASH)) and Controls (n = 81) were recruited. A complete validation analysis was performed to differentiate the presence of MASLD vs. Controls, MASH vs. metabolic-dysfunction associated steatotic liver (MASL), histological features of MASH, and fibrosis stages. RESULTS: The index of NASH (ION) demonstrated the highest differentiation ability for the presence of MASLD vs. Controls, with the area under the curve (AUC) being 0.894. For specific histological characterization of MASH, no NIT demonstrated adequate performance, while in the case of specific features of MASH, such as hepatocellular ballooning and lobular inflammation, ION demonstrated the best performance with AUC being close to or above 0.850. For fibrosis (F) classification, the highest AUC was reached by the aspartate aminotransferase to platelet ratio index (APRI) being ~0.850 yet only with the potential to differentiate the severe fibrosis stages (F3, F4) vs. mild or moderate fibrosis (F0-2) with an AUC > 0.900 in patients without T2DM. When we excluded patients with morbid obesity, the differentiation ability of APRI was improved, reaching AUC = 0.802 for differentiating the presence of fibrosis F2-4 vs. F0-1. The recommended by current guidelines index FIB-4 seemed to differentiate adequately between severe (i.e., F3-4) and mild or moderate fibrosis (F0-2) with an AUC = 0.820, yet this was not the case when FIB-4 was used to classify patients with fibrosis F2-4 vs. F0-1. Trying to improve the predictive value of all NITs, using Youden's methodology, to optimize the suggested cut-off points did not materially improve the results. CONCLUSIONS: The validation of currently available NITs using biopsy-proven samples provides new evidence for their ability to differentiate between specific disease stages, histological features, and, most importantly, fibrosis grading. The overall performance of the examined NITs needs to be further improved for applications in the clinic.


Assuntos
Cirrose Hepática , Hepatopatia Gordurosa não Alcoólica , Humanos , Cirrose Hepática/diagnóstico , Cirrose Hepática/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Testes de Função Hepática , Biópsia , Fígado/patologia , Aspartato Aminotransferases
7.
Diabetes Res Clin Pract ; 203: 110870, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37567510

RESUMO

AIMS: A new non-invasive tool (NIT) for non-alcoholic fatty liver disease (NAFLD) proposed in 2022 by the multi-ethnic Dallas Heart Study, i.e. the Dallas Steatosis Index (DSI), was validated herein using for the first time the gold standard i.e. liver biopsy-proven NAFLD. METHODS: This is a multicenter study based on samples and data from two Gastroenterology-Hepatology Clinics (Greece and Australia) and one Bariatric-Metabolic Surgery Clinic (Italy). Overall, n = 455 patients with biopsy-proven NAFLD (n = 374) and biopsy-proven controls (n = 81) were recruited. RESULTS: The ability of DSI to correctly classify participants as NAFLD or controls was very good, reaching an Area Under the Curve (AUC) = 0.887. The cut-off point that could best differentiate the presence vs. absence of NAFLD corresponded to DSI = 0.0 (risk threshold: 50% | Sensitivity: 0.88; Positive Predictive Value (PPV): 93.0%; F1-score = 0.91). DSI demonstrated significantly better performance characteristics than other liver steatosis indexes. Decision curve analysis revealed that the benefit of DSI as a marker to indicate the need for invasive liver assessment was confirmed only when higher DSI values, i.e. ≥ 1.4, were used as risk thresholds. DSI performance to differentiate disease progression was inadequate (all AUCs < 0.700). CONCLUSIONS: DSI is more useful for disease screening (NAFLD vs. controls) than to differentiate diseases stages or progression. The value of any inclusion of DSI to guidelines needs to be further studied.

9.
Int J Mol Sci ; 24(11)2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37298344

RESUMO

Solute carriers (SLCs) are essential for brain physiology and homeostasis due to their role in transporting necessary substances across cell membranes. There is an increasing need to further unravel their pathophysiological implications since they have been proposed to play a pivotal role in brain tumor development, progression, and the formation of the tumor microenvironment (TME) through the upregulation and downregulation of various amino acid transporters. Due to their implication in malignancy and tumor progression, SLCs are currently positioned at the center of novel pharmacological targeting strategies and drug development. In this review, we discuss the key structural and functional characteristics of the main SLC family members involved in glioma pathogenesis, along with their potential targeting options to provide new opportunities for CNS drug design and more effective glioma management.


Assuntos
Glioma , Proteínas Carreadoras de Solutos , Humanos , Proteínas Carreadoras de Solutos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Transporte Biológico , Desenho de Fármacos , Microambiente Tumoral
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