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1.
Eur J Appl Physiol ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38771358

RESUMEN

PURPOSE: Autophagy and heat shock protein (HSP) response are proteostatic systems involved in the acute and adaptive responses to exercise. These systems may upregulate sequentially following cellular stress including acute exercise, however, currently few data exist in humans. This study investigated the autophagic and HSP responses to acute intense lower body resistance exercise in peripheral blood mononuclear cells (PBMCs) with and without branched-chain amino acids (BCAA) supplementation. METHODS: Twenty resistance-trained males (22.3 ± 1.5 yr; 175.4 ± .7 cm; 86.4 ± 15.6 kg) performed about of intense lower body resistance exercise and markers of autophagy and HSP70 were measured immediately post- (IPE) and 2, 4, 24, 48, and 72 h post-exercise. Prior to resistance exercise, 10 subjects were randomly assigned to BCAA supplementation of 0.22 g/kg/d for 5 days pre-exercise and up to 72 h following exercise while the other 10 subjects consumed a placebo (PLCB). RESULTS: There were no difference in autophagy markers or HSP70 expression between BCAA and PLCB groups. LC3II protein expression was significantly lower 2 and 4 h post-exercise compared to pre-exercise. LC3II: I ratio was not different at any time point compared to pre-exercise. Protein expression of p62 was lower IPE, 2, and 4 h post-exercise and elevated 24 h post-exercise. HSP70 expression was elevated 48 and 72 h post-exercise. CONCLUSIONS: Autophagy and HSP70 are upregulated in PBMCs following intense resistance exercise with autophagy increasing initially post-exercise and HSP response in the latter period. Moreover, BCAA supplementation did not affect this response.

2.
J Clin Transl Sci ; 8(1): e40, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38476242

RESUMEN

Empowering the Participant Voice (EPV) is an NCATS-funded six-CTSA collaboration to develop, demonstrate, and disseminate a low-cost infrastructure for collecting timely feedback from research participants, fostering trust, and providing data for improving clinical translational research. EPV leverages the validated Research Participant Perception Survey (RPPS) and the popular REDCap electronic data-capture platform. This report describes the development of infrastructure designed to overcome identified institutional barriers to routinely collecting participant feedback using RPPS and demonstration use cases. Sites engaged local stakeholders iteratively, incorporating feedback about anticipated value and potential concerns into project design. The team defined common standards and operations, developed software, and produced a detailed planning and implementation Guide. By May 2023, 2,575 participants diverse in age, race, ethnicity, and sex had responded to approximately 13,850 survey invitations (18.6%); 29% of responses included free-text comments. EPV infrastructure enabled sites to routinely access local and multi-site research participant experience data on an interactive analytics dashboard. The EPV learning collaborative continues to test initiatives to improve survey reach and optimize infrastructure and process. Broad uptake of EPV will expand the evidence base, enable hypothesis generation, and drive research-on-research locally and nationally to enhance the clinical research enterprise.

3.
Early Hum Dev ; 190: 105973, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38377881

RESUMEN

OBJECTIVES: To determine the agreement between HNNE and TIMP at TCA for preterm infants born <32+0 weeks' gestation, and to evaluate their correlation to PDMS-2 at 12-month corrected age (CA). METHODS: Infants born between November 2013 to June 2022 who had both HNNE and TIMP performed at TCA of 37+0-41+6 weeks gestation, and motor outcome assessed using the PDMS-2 at 12-month old were enrolled. The HNNE and 12-month PDMS-2 findings were categorized as optimal vs sub-optimal. TIMP was categorized as typical vs atypical. Cohen's kappa was used to determine the agreement between HNNE and TIMP. Sensitivity analysis and Receiver Operating Characteristic (ROC) curves were used to evaluate the predictive values of HNNE and TIMP on motor outcome at CA of 12-months. RESULTS: HNNE and TIMP done on 125 infants at TCA do not show reliable agreement. HNNE demonstrated slight and fair agreement with the 12-month Total Motor Quotient (TMQ) and Fine Motor Quotient (FMQ) of the PDMS-2 respectively. TIMP at TCA demonstrated fair agreement with all sub-domains of motor function on PDMS-2 at 12-months. In comparison with TIMP, HNNE at TCA is more sensitive at predicting suboptimal total, gross and fine motor outcomes at 12-month CA with sensitivity of 68.4 %, 51.9 %, and 83.3 % vs 44.4 %, 31.8 % and 53.3 % respectively. Atypical TIMP at TCA is more specific for suboptimal total, gross and fine motor outcomes at 12-month CA with specificity of 90.3 %, 89 % and 90.5 % respectively. Neurobehavioral assessments at TCA using HNNE and TIMP were predictive of suboptimal fine motor quotient at CA of 12-months with AUC of 0.760 (p = 0.011) and 0.718 (p = 0.032) respectively. The difference in AUC between the 2 instruments of 0.042 was not statistically significant (p = 0.741). CONCLUSIONS: While the HNNE and TIMP done at TCA did not demonstrate significant agreement, suboptimal HNNE and atypical TIMP at TCA were predictive of suboptimal FMQ on PDMS-2 at 12-month CA.


Asunto(s)
Recien Nacido Prematuro , Lactante , Recién Nacido , Humanos , Embarazo , Femenino , Edad Gestacional , Examen Neurológico
4.
J Cell Biochem ; 125(3): e30520, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38226684

RESUMEN

Elevated circulating branched-chain amino acids (BCAAs) have been correlated with the severity of insulin resistance, leading to recent investigations that stimulate BCAA metabolism for the potential benefit of metabolic diseases. BT2 (3,6-dichlorobenzo[b]thiophene-2-carboxylic acid), an inhibitor of branched-chain ketoacid dehydrogenase kinase, promotes BCAA metabolism by enhancing BCKDH complex activity. The purpose of this report was to investigate the effects of BT2 on mitochondrial and glycolytic metabolism, insulin sensitivity, and de novo lipogenesis both with and without insulin resistance. C2C12 myotubes were treated with or without low or moderate levels of BT2 with or without insulin resistance. Western blot and quantitative real-time polymerase chain reaction were used to assess protein and gene expression, respectively. Mitochondrial, nuclei, and lipid content were measured using fluorescent staining and microscopy. Cell metabolism was assessed via oxygen consumption and extracellular acidification rate. Liquid chromatography-mass spectrometry was used to quantify BCAA media content. BT2 treatment consistently promoted mitochondrial uncoupling following 24-h treatment, which occurred largely independent of changes in expressional profiles associated with mitochondrial biogenesis, mitochondrial dynamics, BCAA catabolism, insulin sensitivity, or lipogenesis. Acute metabolic studies revealed a significant and dose-dependent effect of BT2 on mitochondrial proton leak, suggesting BT2 functions as a small-molecule uncoupler. Additionally, BT2 treatment consistently and dose-dependently reduced extracellular BCAA levels without altering expression of BCAA catabolic enzymes or pBCKDHa activation. BT2 appears to act as a small-molecule mitochondrial uncoupler that promotes BCAA utilization, though the interplay between these two observations requires further investigation.


Asunto(s)
Resistencia a la Insulina , Insulina , Humanos , Aminoácidos de Cadena Ramificada/metabolismo , Insulina/metabolismo , Fibras Musculares Esqueléticas , Inhibidores de Proteínas Quinasas/farmacología , Protones
5.
Biochimie ; 219: 155-164, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38008282

RESUMEN

Type 2 diabetes is characterized by elevated circulating blood metabolites such as glucose, insulin, and branched chain amino acids (BCAA), which often coincide with reduced mitochondrial function. 4-Phenylbutyrate (PBA), an ammonia scavenger, has been shown to activate BCAA metabolism, resolve endoplasmic reticulum (ER) stress, and rescue BCAA-mediated insulin resistance. To determine the effect of PBA on the altered metabolic phenotype featured in type 2 diabetes, the present study investigated the effect of PBA on various metabolic parameters including mitochondrial metabolism and mitochondrial biogenesis. C2C12 myotubes were treated with PBA at 0.5 mM (representing physiologically attainable blood concentrations) or 10 mM (representing physiologically unattainable/proof-of-concept levels) for up to 24 h. Mitochondrial and glycolytic metabolism were assessed via oxygen consumption and extracellular acidification rate, respectively. Mitochondrial content, lipid content, and ER stress were measured by fluorescent staining. Metabolic gene expression was measured by qRT-PCR. Both doses of PBA increased expression of indicators of mitochondrial biogenesis, though only PBA at 0.5 mM increased mitochondrial function and content while 10 mM PBA reduced mitochondrial function and content. PBA at 0.5 mM also rescued reduced mitochondrial function during insulin resistance, though PBA also caused a reduced insulin stimulated pAkt expression during insulin resistance. PBA treatment also increased extracellular BCAA accumulation during insulin resistance despite unchanged pBCKDH expression. Taken together, PBA may increase mitochondrial biogenesis, content, and function in a dose-dependent fashion which may have implications for prevention or treatment of metabolic disease such as insulin resistance.


Asunto(s)
Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Fenilbutiratos , Humanos , Diabetes Mellitus Tipo 2/metabolismo , Biogénesis de Organelos , Línea Celular , Fibras Musculares Esqueléticas/metabolismo , Insulina/metabolismo , Aminoácidos de Cadena Ramificada/farmacología , Músculo Esquelético/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo
6.
Mol Ther ; 32(1): 140-151, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-37980543

RESUMEN

Fibrolamellar hepatocellular carcinoma (FLC) is a rare liver cancer caused by a dominant recurrent fusion of the heat shock protein (DNAJB1) and the catalytic subunit of protein kinase A (PRKACA). Current therapies such as chemotherapy and radiation have limited efficacy, and new treatment options are needed urgently. We have previously shown that FLC tumors are dependent on the fusion kinase DNAJB1::PRKACA, making the oncokinase an ideal drug target. mRNA degrading modalities such as antisense oligonucleotides or small interfering RNAs (siRNAs) provide an opportunity to specifically target the fusion junction. Here, we identify a potent and specific siRNA that inhibits DNAJB1::PRKACA expression. We found expression of the asialoglycoprotein receptor in FLC to be maintained at sufficient levels to effectively deliver siRNA conjugated to the GalNAc ligand. We observe productive uptake and siRNA activity in FLC patient-derived xenografts (PDX) models in vitro and in vivo. Knockdown of DNAJB1::PRKACA results in durable growth inhibition of FLC PDX in vivo with no detectable toxicities. Our results suggest that this approach could be a treatment option for FLC patients.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/metabolismo , ARN Interferente Pequeño/genética , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , ARN Bicatenario , Proteínas del Choque Térmico HSP40/genética , Proteínas del Choque Térmico HSP40/metabolismo , Subunidades Catalíticas de Proteína Quinasa Dependientes de AMP Cíclico/genética , Subunidades Catalíticas de Proteína Quinasa Dependientes de AMP Cíclico/metabolismo
7.
Diabet Med ; 41(5): e15271, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38140911

RESUMEN

AIMS: Sodium-glucose cotransporter 2 (SGLT2) inhibitors such as canagliflozin (CANA) have emerged as an effective adjuvant therapy in the management of diabetes, however, past observations suggest CANA may alter skeletal muscle mass and function. The purpose of this work was to investigate the effects of CANA on skeletal muscle metabolism both with and without insulin resistance. METHODS: C2C12 myotubes were treated with CANA with or without insulin resistance. Western blot and qRT-PCR were used to assess protein and gene expression, respectively. Cell metabolism was assessed via oxygen consumption and extracellular acidification rate. Mitochondrial, nuclei and lipid content were measured using fluorescent staining and microscopy. RESULTS: CANA decreased mitochondrial function and glycolytic metabolism as did insulin resistance, however, these changes occurred without significant alterations in gene expression associated with each pathway. Additionally, while insulin resistance reduced insulin-stimulated pAkt expression, CANA had no significant effect on insulin sensitivity. CONCLUSIONS: CANA appears to reduce mitochondrial and glycolytic metabolism without altering gene expression governing these pathways, suggesting a reduction in substrate may be responsible for lower metabolism.


Asunto(s)
Resistencia a la Insulina , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Humanos , Canagliflozina/farmacología , Canagliflozina/uso terapéutico , Inhibidores del Cotransportador de Sodio-Glucosa 2/farmacología , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Hipoglucemiantes/farmacología , Hipoglucemiantes/uso terapéutico , Músculo Esquelético/metabolismo , Mitocondrias/metabolismo
8.
Cell Biochem Funct ; 41(8): 1422-1429, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37916846

RESUMEN

Type 2 diabetes is characterized by elevated blood glucose and reduced insulin sensitivity in target tissues. Moreover, reduced mitochondrial metabolism and expressional profile of genes governing mitochondrial metabolism (such as peroxisome proliferator-activated receptor gamma coactivator 1-alpha [PGC-1α]) are also reduced during insulin resistance. Epigenetic regulation via DNA methylation of genes including PGC-1α may contribute to diminished mitochondrial capacity, while hypomethylation of PGC-1α (such as that invoked by exercise) has been associated with increased PGC-1α expression and favorable metabolic outcomes. The purpose of the present report is to characterize the effects of DNA hypomethylation on myotube metabolism and expression of several related metabolic targets. C2C12 myotubes were treated with 5-Aza-2'-deoxycytidine (5-Aza) for either 24 or 72 h both with and without hyperinsulinemic-induced insulin resistance. Mitochondrial and glycolytic metabolism were measured via oxygen consumption and extracellular acidification rate, respectively. Metabolic gene and protein expression were assessed via quantitative real time polymerase chain reaction and western blot analysis, respectively. Though expression of PGC-1α and other related targets remained unaltered, insulin resistance and 5-Aza treatment significantly reduced mitochondrial metabolism. Similarly, peak glycolytic metabolism was diminished by 5-Aza-treated cells, while basal glycolytic metabolism was unaltered. 5-Aza also reduced the expression of branched-chain amino acid (BCAA) catabolic components, however BCAA utilization was enhanced during insulin resistance with 5-Aza treatment. Together the present work provides proof-of-concept evidence of the potential role of DNA methylation in the regulation of mitochondrial metabolism and the potential interactions with insulin resistance in a model of skeletal muscle.


Asunto(s)
Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Humanos , Resistencia a la Insulina/genética , Decitabina/farmacología , Metilación de ADN , Diabetes Mellitus Tipo 2/metabolismo , Epigénesis Genética , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Insulina/metabolismo , Aminoácidos de Cadena Ramificada/genética , Aminoácidos de Cadena Ramificada/metabolismo , ADN/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/farmacología
9.
Antibiotics (Basel) ; 12(10)2023 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-37887242

RESUMEN

(1) Background: With increasing international travel and mass population displacement due to war, famine, climate change, and immigration, pathogens, such as Staphylococcus aureus (S. aureus), can also spread across borders. Methicillin-resistant S. aureus (MRSA) most commonly causes skin and soft tissue infections (SSTIs), as well as more invasive infections. One clonal strain, S. aureus USA300, originating in the United States, has spread worldwide. We hypothesized that S. aureus USA300 would still be the leading clonal strain among US-born compared to non-US-born residents, even though risk factors for SSTIs may be similar in these two populations (2) Methods: In this study, 421 participants presenting with SSTIs were enrolled from six community health centers (CHCs) in New York City. The prevalence, risk factors, and molecular characteristics for MRSA and specifically clonal strain USA300 were examined in relation to the patients' self-identified country of birth. (3) Results: Patients born in the US were more likely to have S. aureus SSTIs identified as MRSA USA300. While being male and sharing hygiene products with others were also significant risks for MRSA SSTI, we found exposure to animals, such as owning a pet or working at an animal facility, was specifically associated with risk for SSTIs caused by MRSA USA300. Latin American USA300 variant (LV USA300) was most common in participants born in Latin America. Spatial analysis showed that MRSA USA300 SSTI cases were more clustered together compared to other clonal types either from MRSA or methicillin-sensitive S. aureus (MSSA) SSTI cases. (4) Conclusions: Immigrants with S. aureus infections have unique risk factors and S. aureus molecular characteristics that may differ from US-born patients. Hence, it is important to identify birthplace in MRSA surveillance and monitoring. Spatial analysis may also capture additional information for surveillance that other methods do not.

10.
Amino Acids ; 55(11): 1701-1705, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37740788

RESUMEN

Insulin resistance is often accompanied by elevated circulating branched-chain amino acids (BCAA). We investigated the effects of insulin resistance on the mitochondrial BCAA transporter, SLC25A44, using a myotube model of insulin resistance. Insulin sensitivity and SLC25A44 expression were assessed via Western blot. Liquid chromatography-mass spectrometry was used to evaluate extracellular BCAA media content. Insulin resistance reduced pAkt activation following insulin stimulation but did not alter SLC25A44 expression. Under select conditions, insulin resistance led to the accumulation of extracellular BCAA.


Asunto(s)
Aminoácidos de Cadena Ramificada , Resistencia a la Insulina , Humanos , Aminoácidos de Cadena Ramificada/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Insulina/metabolismo
11.
Metabolites ; 13(6)2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37367923

RESUMEN

Population data have shown an association between higher circulating branched-chain amino acids (BCAA) and the severity of insulin resistance in people with diabetes. While several studies have assessed BCAA metabolism as a potential target for regulation, less attention has been paid to the role of L-type amino acid transporter 1 (LAT1), the primary transporter of BCAA in skeletal muscle. The aim of this study was to assess the impact of JPH203 (JPH), a LAT1 inhibitor, on myotube metabolism in both insulin-sensitive and insulin-resistant myotubes. C2C12 myotubes were treated with or without 1 µM or 2 µM JPH for 24 h with or without insulin resistance. Western blot and qRT-PCR were used to assess protein content and gene expression, respectively. Mitochondrial and glycolytic metabolism were measured via Seahorse Assay, and fluorescent staining was used to measure mitochondrial content. BCAA media content was quantified using liquid chromatography-mass spectrometry. JPH at 1 µM (but not 2 µM) increased mitochondrial metabolism and content without inducing changes in mRNA expression of transcripts associated with mitochondrial biogenesis or mitochondrial dynamics. Along with increased mitochondrial function, 1µM treatment also reduced extracellular leucine and valine. JPH at 2 µM reduced pAkt signaling and increased extracellular accumulation of isoleucine without inducing changes in BCAA metabolic genes. Collectively, JPH may increase mitochondrial function independent of the mitochondrial biogenic transcription pathway; however, high doses may reduce insulin signaling.

12.
PPAR Res ; 2023: 4779199, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37325367

RESUMEN

Background: Type 2 diabetes is characterized by reduced insulin sensitivity, elevated blood metabolites, and reduced mitochondrial metabolism with reduced expression of genes governing metabolism such as peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α). PGC-1α regulates the expression of branched-chain amino acid (BCAA) metabolism, and thus, increased circulating BCAA in diabetics may be partially explained by reduced PGC-1α expression. PGC-1α functions in-part through interactions with peroxisome proliferator-activated receptor ß/δ (PPARß/δ). The present report examined the effects of the PPARß/δ agonism on cell metabolism and related gene/protein expression of cultured myotubes, with a primary emphasis on determining the effects of GW on BCAA disposal and catabolic enzyme expression. Methods: C2C12 myotubes were treated with GW501516 (GW) for up to 24 hours. Mitochondrial and glycolytic metabolism were measured via oxygen consumption and extracellular acidification rate, respectively. Metabolic gene and protein expression were assessed via quantitative real-time polymerase chain reaction (qRT-PCR) and western blot, respectively. Media BCAA content was assessed via liquid chromatography-mass spectrometry (LC/MS). Results: GW significantly increased PGC-1α protein expression, mitochondrial content, and mitochondrial function. GW also significantly reduced BCAA content within culture media following 24-hour treatment; however, expression of BCAA catabolic enzymes/transporter was unchanged. Conclusion: These data confirm the ability of GW to increase muscle PGC-1α content and decrease BCAA media content without affecting BCAA catabolic enzymes/transporter. These findings suggest heightened BCAA uptake (and possibly metabolism) may occur without substantial changes in the protein levels of related cell machinery.

13.
J Clin Transl Sci ; 7(1): e104, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37250985

RESUMEN

Introduction: Clinical trials are a vital component of translational science, providing crucial information on the efficacy and safety of new interventions and forming the basis for regulatory approval and/or clinical adoption. At the same time, they are complex to design, conduct, monitor, and report successfully. Concerns over the last two decades about the quality of the design and the lack of completion and reporting of clinical trials, characterized as a lack of "informativeness," highlighted by the experience during the COVID-19 pandemic, have led to several initiatives to address the serious shortcomings of the United States clinical research enterprise. Methods and Results: Against this background, we detail the policies, procedures, and programs that we have developed in The Rockefeller University Center for Clinical and Translational Science (CCTS), supported by a Clinical and Translational Science Award (CTSA) program grant since 2006, to support the development, conduct, and reporting of informative clinical studies. Conclusions: We have focused on building a data-driven infrastructure to both assist individual investigators and bring translational science to each element of the clinical investigation process, with the goal of both generating new knowledge and accelerating the uptake of that knowledge into practice.

14.
STAR Protoc ; 4(2): 102302, 2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37178115

RESUMEN

The AutoScore framework can automatically generate data-driven clinical scores in various clinical applications. Here, we present a protocol for developing clinical scoring systems for binary, survival, and ordinal outcomes using the open-source AutoScore package. We describe steps for package installation, detailed data processing and checking, and variable ranking. We then explain how to iterate through steps for variable selection, score generation, fine-tuning, and evaluation to generate understandable and explainable scoring systems using data-driven evidence and clinical knowledge. For complete details on the use and execution of this protocol, please refer to Xie et al. (2020),1 Xie et al. (2022)2, Saffari et al. (2022)3 and the online tutorial https://nliulab.github.io/AutoScore/.

15.
Amino Acids ; 55(2): 275-286, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36547760

RESUMEN

Those with insulin resistance often display increased circulating branched-chain amino acids (BCAA), which has been largely attributable to reduced BCAA catabolic capacity. Metabolic stimuli such as exercise activates AMP-activated kinase (AMPK), which promotes the metabolism of BCAA and induction/activation of BCAA catabolic enzymes. Though much attention has been paid to BCAA catabolic machinery, few studies have assessed the effect of AMPK activation on the predominant BCAA transporter, L-type amino acid transporter 1 (LAT1). This study assessed the effect of AMPK activation on LAT1 expression via common chemical AMPK activators in a cell model of skeletal muscle. C2C12 myotubes were treated with either 1 mM AICAR, 1 mM Metformin, or filter-sterilized water (control) for 24 h with either low- (5 mM) or high-glucose (25 mM) media. LAT1 and pAMPK protein content were measured via western blot. BCAA media content was measured using liquid chromatography-mass spectrometry. AICAR treatment significantly increased pAMPK and reduced LAT1 expression. Collectively, pAMPK and LAT1 displayed a significant inverse relationship independent of glucose levels. During low-glucose experiments, AICAR-treated cells had higher BCAA media content compared to other groups, and an inverse relationship between LAT1 and BCAA media content was observed, however, these effects were not consistently observed during high-glucose conditions. Further investigation with AICAR with and without concurrent LAT1 inhibition (via JPH203) also revealed reduced BCAA utilization in AICAR-treated cells regardless of LAT1 inhibition (which also independently reduced BCAA utilization). pAMPK activation via AICAR (but not Metformin) may reduce LAT1 expression and BCAA uptake in a glucose-dependent manner.


Asunto(s)
Glucosa , Metformina , Aminoácidos de Cadena Ramificada/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Glucosa/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Ratones , Animales
16.
Clin Cancer Res ; 29(1): 271-278, 2023 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-36302174

RESUMEN

PURPOSE: Gene fusions are drivers of many pediatric tumors. In fibrolamellar hepatocellular carcinoma (FLC), a fusion of DNAJB1 and PRKACA is the dominant recurrent mutation. Expression of the DNAJB1-PRKACA fusion gene in mice results in a tumor that recapitulates FLC. However, it is not known whether transient expression of DNAJB1-PRKACA is sufficient only to trigger tumor formation or whether ongoing expression is necessary for maintenance and progression. EXPERIMENTAL DESIGN: We screened short hairpin RNAs (shRNA) tiled over the fusion junction and identified several potent and specific candidates in vitro and two independent FLC patient-derived xenografts (PDX). RESULTS: We show that continued DNAJB1-PRKACA expression is not only required for continued tumor growth, but additionally its inhibition results in cell death. Inhibition of DNAJB1-PRKACA by an inducible shRNA in cells of PDX of FLC resulted in cell death in vitro. Induction of the shRNA inhibits FLC tumors growing in mice with no effect on xenografts from a hepatocellular carcinoma cell line engineered to express DNAJB1-PRKACA. CONCLUSIONS: Our results validate DNAJB1-PRKACA as the oncogene in FLC and demonstrate both a continued requirement for the oncogene for tumor growth as well as an oncogenic addiction that can be exploited for targeted therapies. We anticipate our approach will be useful for investigations of other fusion genes in pediatric cancers and spur development of precision therapies.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Animales , Ratones , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/patología , Dependencia del Oncogén , ARN Interferente Pequeño/genética , Proteínas del Choque Térmico HSP40/genética , Proteínas del Choque Térmico HSP40/metabolismo , Subunidades Catalíticas de Proteína Quinasa Dependientes de AMP Cíclico/genética , Subunidades Catalíticas de Proteína Quinasa Dependientes de AMP Cíclico/metabolismo
17.
Mol Cell Endocrinol ; 559: 111800, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36270542

RESUMEN

PURPOSE: Type 2 diabetes is characterized by reduced insulin sensitivity which correlates with increased circulating BCAA. These experiments investigated the effects of insulin resistance with and without excess BCAA on myotube insulin sensitivity and L-type amino acid transporter-1 (LAT1). METHODS: C2C12 myotubes were treated with or without excess BCAA for 1 or 6 days, both with and without insulin resistance. Western blot was used to assess insulin sensitivity and LAT1 content. Liquid chromatography-mass spectrometry was used to evaluate BCAA media content. RESULTS: Insulin resistance was associated with significantly increased extracellular BCAA accumulation independent of LAT1 content. Conversely, prior BCAA treatment was not associated with extracellular BCAA accumulation regardless of level of insulin sensitivity. CONCLUSION: These data suggest insulin resistance, but not BCAA treatment, promotes extracellular BCAA accumulation independent of changes in LAT1 content, implicating insulin resistance as a causal agent of extracellular BCAA accumulation.


Asunto(s)
Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Humanos , Resistencia a la Insulina/fisiología , Aminoácidos de Cadena Ramificada/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo
18.
Am J Physiol Endocrinol Metab ; 324(2): E144-E153, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36576355

RESUMEN

Although brown fat is strongly associated with a constellation of cardiometabolic benefits in animal models and humans, it has also been tied to cancer cachexia. In humans, cancer-associated cachexia increases mortality, raising the possibility that brown fat in this context may be associated with increased cancer death. However, the effect of brown fat on cancer-associated cachexia and survival in humans remains unclear. Here, we retrospectively identify patients with and without brown fat on fluorodeoxyglucose (18F-FDG) positron-emission tomography (PET) scans obtained as part of routine cancer care and assemble a cohort to address these questions. We did not find an association between brown fat status and cachexia. Furthermore, we did not observe an association between brown fat and increased mortality in patients with cachexia. Our analyses controlled for confounding factors including age at cancer diagnosis, sex, body mass index, cancer site, cancer stage, outdoor temperature, comorbid conditions (heart failure, type 2 diabetes mellitus, coronary artery disease, hypertension, dyslipidemia, cerebrovascular disease), and ß-blocker use. Taken together, our results suggest that brown fat is not linked to cancer-associated cachexia and does not worsen overall survival in patients with cachexia.NEW & NOTEWORTHY This study finds that brown fat is not linked to cancer-associated cachexia. Moreover, this work shows that brown fat does not worsen overall survival in patients with cachexia.


Asunto(s)
Diabetes Mellitus Tipo 2 , Neoplasias , Animales , Humanos , Tejido Adiposo Pardo/diagnóstico por imagen , Estudios Retrospectivos , Caquexia , Diabetes Mellitus Tipo 2/complicaciones , Fluorodesoxiglucosa F18 , Tomografía de Emisión de Positrones/métodos , Neoplasias/complicaciones
19.
Am J Public Health ; 113(1): 35-36, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36516382
20.
Nutrients ; 14(22)2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36432576

RESUMEN

Low-income, minority seniors face high rates of hypertension that increase cardiovascular risk. Senior centers offer services, including congregate meals, that can be a valuable platform to reach older adults in underserved communities. We implemented two evidence-based interventions not previously tested in this setting: DASH-aligned congregate meals and Self-Measured Blood Pressure (SMBP), to lower blood pressure (BP) at two senior centers serving low-income, racially diverse communities. The study enrolled congregate meal program participants, provided training and support for SMPB, and nutrition and BP education. DASH-aligned meals delivered 40% (lunch) or 70% (breakfast and lunch) of DASH requirements/day. Primary outcomes were change in BP, and BP control, at Month 1. Implementation data collected included client characteristics, menu fidelity, meal attendance, SMBP adherence, meal satisfaction, input from partner organizations and stakeholders, effort, and food costs. We used the RE-AIM framework to analyze implementation. Study Reach included 94 older, racially diverse participants reflecting neighborhood characteristics. Effectiveness: change in systolic BP at Month 1 trended towards significance (-4 mmHg, p = 0.07); change in SMBP reached significance at Month 6 (-6.9 mmHg, p = 0.004). We leveraged existing community-academic partnerships, leading to Adoption at both target sites. The COVID pandemic interrupted Implementation and Maintenance and may have attenuated BP effectiveness. DASH meals served were largely aligned with planned menus. Meal attendance remained consistent; meal satisfaction was high. Food costs increased by 10%. This RE-AIM analysis highlights the acceptability, feasibility, and fidelity of this DASH/SMBP health intervention to lower BP at senior centers. It encourages future research and offers important lessons for organizations delivering services to older adults and addressing cardiovascular risk among vulnerable populations.


Asunto(s)
COVID-19 , Hipertensión , Humanos , Anciano , Presión Sanguínea , COVID-19/epidemiología , COVID-19/prevención & control , Hipertensión/epidemiología , Hipertensión/prevención & control , Comidas , Almuerzo
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