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1.
Brain Behav Immun ; 117: 205-214, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38244945

RESUMO

Although cancer and its therapy are well known to be associated with fatigue, the exact nature of cancer-related fatigue remains ill-defined. We previously reported that fatigue-like behavior induced independently by tumor growth and by the chemotherapeutic agent cisplatin is characterized by reduced voluntary wheel running and an intact motivation to expand effort for food rewards. The present set of experiments was initiated to characterize the functional consequences of fatigue induced by chemoradiotherapy in tumor-bearing mice and relate them to changes in the expression of genes coding for inflammation, mitochondria dynamics and metabolism. Two syngeneic murine models of cancer were selected for this purpose, a model of human papilloma virus-related head and neck cancer and a model of lung cancer. In both models, tumor-bearing mice were submitted to chemoradiotherapy to limit tumor progression. Two dimensions of fatigue were assessed, the physical dimension by changes in physical activity in mice trained to run in wheels and the motivational dimension by changes in the performance of mice trained to nose poke to obtain a food reward in a progressive ratio schedule of food reinforcement. Chemoradiotherapy reliably decreased wheel running activity but had no effect on performance in the progressive ratio in both murine models of cancer. These effects were the same for the two murine models of cancer and did not differ according to sex. Livers and brains were collected at the end of the experiments for qRT-PCR analysis of expression of genes coding for inflammation, mitochondria dynamics, and metabolism. The observed changes were mainly apparent in the liver and typical of activation of type I interferon and NF-κB-dependent signaling, with alterations in mitochondrial dynamics and a shift toward glycolysis. Although the importance of these alterations for the pathophysiology of cancer-related fatigue remains to be explored, the present findings indicate that fatigue brought on by cancer therapy in tumor-bearing mice is more physical than motivational.


Assuntos
Neoplasias de Cabeça e Pescoço , Atividade Motora , Humanos , Animais , Camundongos , Encéfalo/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Motivação , Inflamação/metabolismo
2.
Org Biomol Chem ; 21(2): 252-272, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36504200

RESUMO

Asymmetric organocatalysis is a growing method for the synthesis of axially chiral tetrasubstituted allenes, the most challenging one among allene syntheses. In this method, chiral organocatalysts such as phase-transfer catalysts, peptides, disulfonimides, and binaphthyl/bispiro phosphoric acids have displayed remote control of regio- and stereoselectivity. Highly functionalized enantiopure allenes including those with an adjacent tertiary or quaternary stereocenter have been efficiently prepared with high levels of regio-, diastereo-, and enantioselectivity using this method. Several mechanistic pathways, including electrophilic addition to cumulenolate or zwitterionic enolate intermediates, alkynylogous Mukaiyama aldol reaction, nucleophilic addition to quinone methides, and dearomative addition to imino esters, were proposed. The method is necessary for providing access to axially chiral tetrasubstituted allenes, which can be utilized for the preparation of novel ligands, natural products, and organic materials, particularly those having complex structures. This review covers the enantioselective organocatalytic synthesis of these tetrasubstituted allenes and the mechanistic insights into the formation of the chiral axis up to July 2022.


Assuntos
Alcadienos , Estereoisomerismo , Alcadienos/química , Catálise
3.
Int J Mol Sci ; 23(12)2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35743063

RESUMO

Lymphedema and lipedema are complex diseases. While the external presentation of swollen legs in lower-extremity lymphedema and lipedema appear similar, current mechanistic understandings of these diseases indicate unique aspects of their underlying pathophysiology. They share certain clinical features, such as fluid (edema), fat (adipose expansion), and fibrosis (extracellular matrix remodeling). Yet, these diverge on their time course and known molecular regulators of pathophysiology and genetics. This divergence likely indicates a unique route leading to interstitial fluid accumulation and subsequent inflammation in lymphedema versus lipedema. Identifying disease mechanisms that are causal and which are merely indicative of the condition is far more explored in lymphedema than in lipedema. In primary lymphedema, discoveries of genetic mutations link molecular markers to mechanisms of lymphatic disease. Much work remains in this area towards better risk assessment of secondary lymphedema and the hopeful discovery of validated genetic diagnostics for lipedema. The purpose of this review is to expose the distinct and shared (i) clinical criteria and symptomatology, (ii) molecular regulators and pathophysiology, and (iii) genetic markers of lymphedema and lipedema to help inform future research in this field.


Assuntos
Lipedema , Linfedema , Tecido Adiposo/patologia , Edema/patologia , Fibrose , Humanos , Lipedema/diagnóstico , Lipedema/genética , Linfedema/genética , Linfedema/patologia
4.
Sensors (Basel) ; 21(2)2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33477491

RESUMO

Underwater wireless sensor networks are currently seeing broad research in various applications for human benefits. Large numbers of sensor nodes are being deployed in rivers and oceans to monitor the underwater environment. In the paper, we propose an energy-efficient clustering multi-hop routing protocol (EECMR) which can balance the energy consumption of these nodes and increase their network lifetime. The network area is divided into layers with regard to the depth level. The data sensed by the nodes are transmitted to a sink via a multi-hop routing path. The cluster head is selected according to the depth of the node and its residual energy. To transmit data from the node to the sink, the cluster head aggregates the data packet of all cluster members and then forwards them to the upper layer of the sink node. The simulation results show that EECMR is effective in terms of network lifetime and the nodes' energy consumption.

5.
Inflamm Res ; 69(3): 309-319, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32002586

RESUMO

OBJECTIVE: This study aimed to evaluate the protective effect of igalan, a sesquiterpene lactone isolated from Inula helenium (L.), on inhibiting inflammation, regulating the epidermal differentiation gene expression, and reactive oxygen species scavenging in atopic dermatitis (AD)-like inflammatory keratinocytes. METHODS: HaCaT human keratinocytes were treated with igalan at indicated concentrations before being activated by a combination of TNF-α and IFN-γ or IL-4 representative for T-helper 1 and T-helper 2 cell cytokines, which are associated with AD pathogenesis. RESULTS: By inhibiting the NF-κB pathway as well as the STAT activation, igalan could downregulate several marker inflammatory genes in AD, such as TARC/CCL17, MDC/CCL22, and RANTES/CCL5. In contrast, igalan, acting as JAK inhibitor, could promote the mRNA expression levels of the genes FLG, LOR, KRT10, and DSC1, which encode for essential proteins responsible for keratinocyte differentiation, by inhibiting STAT3 signaling. Furthermore, igalan exerts its antioxidant effect through activating the Nrf2 pathway, triggering the expression of some enzymes that contribute to preventing intracellular ROS generation during inflammation. CONCLUSION: These findings indicate that igalan, via suppressing JAK/STAT3 signaling, could impair the production of pro-inflammatory chemokines and enhance expression levels of several genes involved in keratinocyte differentiation in AD-like stimulated keratinocytes.


Assuntos
Dermatite Atópica/metabolismo , Inula/química , Queratinócitos/metabolismo , Lactonas/química , Extratos Vegetais/farmacologia , Sesquiterpenos/química , Diferenciação Celular , Citocinas/metabolismo , Dermatite Atópica/tratamento farmacológico , Epiderme/metabolismo , Proteínas Filagrinas , Células HaCaT , Humanos , Inflamação , Interferon gama/metabolismo , Interleucina-4/metabolismo , Janus Quinase 1/metabolismo , Queratinócitos/efeitos dos fármacos , Subunidade p50 de NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT3/metabolismo , Células Th1/metabolismo , Células Th2/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
6.
Org Biomol Chem ; 17(29): 6952-6963, 2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31268093

RESUMO

Traceless point-to-axial chirality exchange is a growing method for the preparation of axially chiral biaryls/heterobiaryls. During the exchange, stereogenic centers are destroyed and a chiral axis is simultaneously created. Highly functionalized enantiopure biaryls/heterobiaryls including those containing furanyl, thiophenyl, or pyrrolyl moieties with low rotation barriers have been prepared using this strategy with high levels of chirality transfer. The method is necessary for providing access to novel ligands, catalysts, natural products and active drugs having chiral axes. This review focuses on the chirality exchange approach for the formation of axially chiral biaryls/heterobiaryls and stereochemical models for the control of atropselectivity up to April 2019.

7.
Molecules ; 24(17)2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31443460

RESUMO

Background: This research aimed to investigate the cytotoxicity of methanol extract of Smallanthus sonchifolius leaf (YLE) against a human hepatocellular carcinoma cell line (HepG2). This plant is currently used as a traditional herbal remedy in the treatment of liver diseases in some rural parts of Myanmar. Methods: The cytotoxic activity of the plant extract against the cancerous cell line was assessed using an MTT assay. YLE demonstrated a significant effect (IC50 = 58.2 ± 1.9 µg/mL) on anti-cancer activity, which was further investigated using various assays including an in vitro cell migration assay, a colony formation assay, cell cycle analysis, western blot analysis, and a ROS assay. The significance of the phytochemical constituents of YLE could be identified using LC/Q-TOF-MS techniques. Results: We putatively identified the active components in YLE, which were possibly melampolide-type sesquiterpenoids. YLE showed an inhibitory effect on HepG2 cell proliferation and cell migration. YLE also induced cell cycle arrest and necrosis in a dose-dependent manner. Additionally, YLE significantly suppressed ROS formation in HepG2 cells. Conclusions: These findings suggest that YLE is sufficient for application as a promising anti-liver drug in herbal medicine.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Asteraceae/química , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/química , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia , Humanos , Extração Líquido-Líquido , Neoplasias Hepáticas , Metanol , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Cicatrização
8.
Sensors (Basel) ; 17(10)2017 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-28956827

RESUMO

As wireless body area networks (WBANs) become a key element in electronic healthcare (e-healthcare) systems, the coexistence of multiple mobile WBANs is becoming an issue. The network performance is negatively affected by the unpredictable movement of the human body. In such an environment, inter-WBAN interference can be caused by the overlapping transmission range of nearby WBANs. We propose a link scheduling algorithm with interference prediction (LSIP) for multiple mobile WBANs, which allows multiple mobile WBANs to transmit at the same time without causing inter-WBAN interference. In the LSIP, a superframe includes the contention access phase using carrier sense multiple access with collision avoidance (CSMA/CA) and the scheduled phase using time division multiple access (TDMA) for non-interfering nodes and interfering nodes, respectively. For interference prediction, we define a parameter called interference duration as the duration during which disparate WBANs interfere with each other. The Bayesian model is used to estimate and classify the interference using a signal to interference plus noise ratio (SINR) and the number of neighboring WBANs. The simulation results show that the proposed LSIP algorithm improves the packet delivery ratio and throughput significantly with acceptable delay.

9.
Sensors (Basel) ; 16(12)2016 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-27999385

RESUMO

Currently, wireless body area networks (WBANs) are effectively used for health monitoring services. However, in cases where WBANs are densely deployed, interference among WBANs can cause serious degradation of network performance and reliability. Inter-WBAN interference can be reduced by scheduling the communication links of interfering WBANs. In this paper, we propose an interference-aware traffic-priority-based link scheduling (ITLS) algorithm to overcome inter-WBAN interference in densely deployed WBANs. First, we model a network with multiple WBANs as an interference graph where node-level interference and traffic priority are taken into account. Second, we formulate link scheduling for multiple WBANs as an optimization model where the objective is to maximize the throughput of the entire network while ensuring the traffic priority of sensor nodes. Finally, we propose the ITLS algorithm for multiple WBANs on the basis of the optimization model. High spatial reuse is also achieved in the proposed ITLS algorithm. The proposed ITLS achieves high spatial reuse while considering traffic priority, packet length, and the number of interfered sensor nodes. Our simulation results show that the proposed ITLS significantly increases spatial reuse and network throughput with lower delay by mitigating inter-WBAN interference.


Assuntos
Algoritmos , Redes de Comunicação de Computadores , Tecnologia sem Fio , Simulação por Computador , Humanos
10.
Am Heart J ; 169(6): 758-766.e6, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26027612

RESUMO

BACKGROUND: Both acute myocardial ischemia and reperfusion contribute to cardiomyocyte death in ST-elevation myocardial infarction (STEMI). The final infarct size is the principal determinant of subsequent clinical outcome in STEMI patients. In a proof-of-concept phase II trial, the administration of cyclosporine prior to primary percutaneous coronary intervention (PPCI) has been associated with a reduction of infarct size in STEMI patients. METHODS: CIRCUS is an international, prospective, multicenter, randomized, double-blinded, placebo-controlled trial. The study is designed to compare the efficacy and safety of cyclosporine versus placebo, in addition to revascularization by PPCI, in patients presenting with acute anterior myocardial infarction within 12 hours of symptoms onset and initial TIMI flow ≤1 in the culprit left anterior descending coronary artery. Patients are randomized in a 1:1 fashion to 2.5 mg/kg intravenous infusion of cyclosporine or matching placebo performed in the minutes preceding PCI. The primary efficacy end point of CIRCUS is a composite of 1-year all-cause mortality, rehospitalization for heart failure or heart failure worsening during initial hospitalization, and left ventricular adverse remodeling as determined by sequential transthoracic echochardiography. Secondary outcomes will be tested using a hierarchical sequence of left ventricular (LV) ejection fraction and absolute measurements of LV volumes. The composite of death and rehospitalization for heart failure or heart failure worsening during initial hospitalization will be further assessed at three years after the initial infarction. RESULTS: Recruitment lasted from April 2011 to February 2014. The CIRCUS trial has recruited 975 patients with acute anterior myocardial infarction. The 12-months results are expected to be available in 2015. CONCLUSIONS: The CIRCUS trial is testing the hypothesis that cyclosporine in addition to early revascularization with PPCI compared to placebo in patients with acute anterior myocardial infarction reduces the incidence of death, heart failure and adverse LV remodeling at one-year follow-up.


Assuntos
Ciclosporina/efeitos adversos , Ciclosporina/uso terapêutico , Infarto do Miocárdio/cirurgia , Intervenção Coronária Percutânea , Biomarcadores/sangue , Angiografia Coronária , Método Duplo-Cego , Ecocardiografia , Eletrocardiografia , Feminino , Humanos , Masculino , Infarto do Miocárdio/fisiopatologia , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento
11.
Sensors (Basel) ; 15(6): 13805-38, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-26110407

RESUMO

A wireless body area sensor network (WBASN) consists of a coordinator and multiple sensors to monitor the biological signals and functions of the human body. This exciting area has motivated new research and standardization processes, especially in the area of WBASN performance and reliability. In scenarios of mobility or overlapped WBASNs, system performance will be significantly degraded because of unstable signal integrity. Hence, it is necessary to consider interference mitigation in the design. This survey presents a comparative review of interference mitigation schemes in WBASNs. Further, we show that current solutions are limited in reaching satisfactory performance, and thus, more advanced solutions should be developed in the future.


Assuntos
Redes de Comunicação de Computadores , Tecnologia de Sensoriamento Remoto , Processamento de Sinais Assistido por Computador , Tecnologia sem Fio , Algoritmos , Humanos
13.
Proc Natl Acad Sci U S A ; 108(1): 143-8, 2011 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-21173238

RESUMO

Brown fat is specialized for energy expenditure and has therefore been proposed to function as a defense against obesity. Despite recent advances in delineating the transcriptional regulation of brown adipocyte differentiation, cellular lineage specification and developmental cues specifying brown-fat cell fate remain poorly understood. In this study, we identify and isolate a subpopulation of adipogenic progenitors (Sca-1(+)/CD45(-)/Mac1(-); referred to as Sca-1(+) progenitor cells, ScaPCs) residing in murine brown fat, white fat, and skeletal muscle. ScaPCs derived from different tissues possess unique molecular expression signatures and adipogenic capacities. Importantly, although the ScaPCs from interscapular brown adipose tissue (BAT) are constitutively committed brown-fat progenitors, Sca-1(+) cells from skeletal muscle and subcutaneous white fat are highly inducible to differentiate into brown-like adipocytes upon stimulation with bone morphogenetic protein 7 (BMP7). Consistent with these findings, human preadipocytes isolated from subcutaneous white fat also exhibit the greatest inducible capacity to become brown adipocytes compared with cells isolated from mesenteric or omental white fat. When muscle-resident ScaPCs are re-engrafted into skeletal muscle of syngeneic mice, BMP7-treated ScaPCs efficiently develop into adipose tissue with brown fat-specific characteristics. Importantly, ScaPCs from obesity-resistant mice exhibit markedly higher thermogenic capacity compared with cells isolated from obesity-prone mice. These data establish the molecular characteristics of tissue-resident adipose progenitors and demonstrate a dynamic interplay between these progenitors and inductive signals that act in concert to specify brown adipocyte development.


Assuntos
Adipócitos Marrons/fisiologia , Tecido Adiposo Branco/citologia , Antígenos Ly/metabolismo , Diferenciação Celular/fisiologia , Proteínas de Membrana/metabolismo , Músculo Esquelético/citologia , Células-Tronco/fisiologia , Adipócitos Marrons/citologia , Animais , Western Blotting , Proteína Morfogenética Óssea 7/metabolismo , Citometria de Fluxo , Imunofluorescência , Humanos , Imuno-Histoquímica , Camundongos , Termogênese/fisiologia
14.
Phys Med Biol ; 69(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38529716

RESUMO

Objective. Lutetium yttrium oxyorthosilicate (LYSO) scintillation crystals are used in positron emission tomography (PET) due to their high gamma attenuation, fair energy resolution, and fast scintillation decay time. The enduring presence of the176Lu isotope, characterized by a half-life of 37.9 billion years, imparts a consistent radiation background (BG) profile that depends on the geometry and composition attributes of the LYSO crystals.Approach. In this work, we proposed a methodology for estimating the composition of LYSO crystals in cases where the exact Lutetium composition remains unknown. The connection between BG spectrum intensity and intrinsic radioactivity enables precise estimation of Lutetium density in LYSO crystal samples. This methodology was initially applied to a well-characterized LYSO crystal sample, yielding results closely aligned with the known composition. The composition estimation approach was extended to several samples of undisclosed LYSO crystals, encompassing single crystal and crystal array configurations. Furthermore, we model the background spectrum observed in the LYSO-based detector and validate the observed spectra via simulations.Main results. The estimated Lutetium composition exhibited adequate consistency across different samples of the same LYSO material, with variations of less than 1%. The result of the proposed approach coupled with the simulation successfully models the background radiation spectra in various LYSO-based detector geometries.Significance. The implications of this work extend to the predictive assessment of system behaviors and the autonomous configuration parameters governing LYSO-based detectors.


Assuntos
Lutécio , Ítrio , Lutécio/química , Tomografia por Emissão de Pósitrons/métodos , Silicatos/química
15.
Cureus ; 16(6): e62317, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38882227

RESUMO

Background The characteristics of amplitude-integrated electroencephalography (aEEG) are associated with neurological outcomes in neonates with hypoxic-ischemic encephalopathy (HIE). We perform a longitudinal analysis of continuous monitoring of aEEG during therapeutic hypothermia and explore the association between aEEG interpretation and clinical neurological outcomes. Method We conducted a prospective cohort study on HIE neonates undergoing hypothermia with aEEG monitoring. Results A total of 37 HIE infants underwent hypothermia with improved aEEG background activity in 28 (75.7%) neonates, of which 18 (48.6%) neonates had background activity returned to a continuous pattern, and the median recovery time was 26.5 hours. Sleep-wake cycle (SWC) appeared in 14 (37.8%) cases, with a median onset time of 34.5 hours. Seizure activity on aEEG was present in 26 (70.3%) infants. Factors associated with poor outcomes at discharge included low voltage or flat trace background activity, a lack of improvement in background activity after hypothermia, and the absence of SWC. Neonates who took longer than 62 hours to return to continuous background activity (time to normal trace) or did not have SWC before the end of hypothermia were more likely to have unfavorable outcomes at discharge. Conclusions Longitudinal analysis of aEEG during hypothermia should be implemented in neonatal care units. The progression of these features on aEEG may predict neurological outcomes for HIE neonates.

16.
Cureus ; 16(3): e56403, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38638757

RESUMO

INTRODUCTION: Although the use of peripherally inserted central catheters (PICCs) has many advantages, misplacement can lead to serious life-threatening complications such as pericardial effusion (PCE) and cardiac tamponade (CT). This report aims to describe four cases of CT resulting from misplaced PICC, which were successfully managed. METHODS: Retrospective analysis of neonates who required PICC insertion and had PCE leading to CT in the Neonatal Intensive Care Unit (NICU) at The Children's Hospital 2, Ho Chi Minh City, Vietnam, during the year 2022. RESULTS: Four cases involved preterm infants at 28-30 weeks gestational age, weighing between 900-1,500 grams. The PCE/CT developed between 3 and 24 days following PICC insertion. The abrupt onset with clinical manifestations that showed hemodynamic instability included sudden deterioration, lethargy, apnea, bradycardia, pale skin, and cardiovascular collapse. We use cardiac point of care ultrasound (POCUS) to assess the condition of these patients and guide the pericardiocentesis procedure. The analysis of the aspirated fluid used for PCE/CT treatment is consistent with the component of parenteral nutrition. No deaths were encountered. CONCLUSION: Neonates presenting sudden deterioration following PICC insertion should undergo POCUS to prompt identifying PCE/CT. Timely diagnosis via POCUS, prompt pericardiocentesis, and prevention of misplaced PICC-associated serious complications are crucial. Monitoring of the PICC position twice a week is recommended to avoid life-threatening complications. Additionally, incorporating POCUS for identifying the tip of PICC rather than relying solely on X-ray should be considered in the current protocol.

17.
RSC Adv ; 13(45): 31811-31819, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37908664

RESUMO

A computational NMR approach for accurate predicting the 1H/13C chemical shifts of triterpenoid oximes featuring the screening of 144 DFT methods was demonstrated. Efficiently synthesized dipterocarpol oxime was employed as a model compound. The six highest accurate methods from the screening generated root-mean-square-error (RMSE) values in the range of 0.84 ppm (0.55%) to 1.14 ppm (0.75%) for calculated 13C shifts. For 1H results, simple, economical 6-31G basis set unexpectedly outperformed other more expensive basic sets; and the couple of it with selected functionals provided high accuracy shifts (0.0617 ppm (1.49%) ≤ RMSE ≤ 0.0870 ppm (2.04%)). These computational results strongly supported the proton and carbon assignments of the oxime including the difficult ones of diastereotopic methyl groups, the methyl groups attached to an internal olefin, and diastereotopic α-protons.

18.
Front Cell Dev Biol ; 11: 1100788, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36776563

RESUMO

During cold exposure, white adipose tissue can remodel to dissipate energy as heat under cold similar to thermogenic brown adipose tissue. This "browning" and the regulation of body temperature is under the control of neural and hormonal signaling. It was recently discovered that neurotensin, a small neuropeptide, not only acts to inhibit thermogenesis, but also that lymphatic vessels may be a surprisingly potent source of neurotensin production. We hypothesized that the induction of adipose tissue lymphangiogenesis would therefore increase tissue neurotensin levels and impair thermogenesis. Methods: We utilized AdipoVD mice that have inducible expression of vascular endothelial growth factor (VEGF)-D, a potent lymphangiogenic stimulator, specifically in adipose tissue. Overexpression of VEGF-D induced significant lymphangiogenesis in both white and brown adipose tissues of AdipoVD mice. Results: Obese Adipo-VD mice demonstrated no differences in adipose morphology or browning under room temperature conditions compared to controls but did express significantly higher levels of neurotensin in their adipose tissues. Upon acute cold exposure, AdipoVD mice were markedly cold intolerant; inhibition of neurotensin signaling ameliorated this cold intolerance as AdipoVD mice were then able to maintain body temperature on cold challenge equivalent to their littermates. Conclusion: In total, these data demonstrate that adipose tissue lymphatic vessels are a potent paracrine source of neurotensin and that lymphangiogenesis therefore impairs the tissues' thermogenic ability.

19.
Theranostics ; 13(2): 438-457, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36632231

RESUMO

Rationale: Despite growing evidence for mitochondria's involvement in cancer, the roles of specific metabolic components outside the respiratory complex have been little explored. We conducted metabolomic studies on mitochondrial DNA (mtDNA)-deficient (ρ0) cancer cells with lower proliferation rates to clarify the undefined roles of mitochondria in cancer growth. Methods and results: Despite extensive metabolic downregulation, ρ0 cells exhibited high glycerol-3-phosphate (G3P) level, due to low activity of mitochondrial glycerol-3-phosphate dehydrogenase (GPD2). Knockout (KO) of GPD2 resulted in cell growth suppression as well as inhibition of tumor progression in vivo. Surprisingly, this was unrelated to the conventional bioenergetic function of GPD2. Instead, multi-omics results suggested major changes in ether lipid metabolism, for which GPD2 provides dihydroxyacetone phosphate (DHAP) in ether lipid biosynthesis. GPD2 KO cells exhibited significantly lower ether lipid level, and their slower growth was rescued by supplementation of a DHAP precursor or ether lipids. Mechanistically, ether lipid metabolism was associated with Akt pathway, and the downregulation of Akt/mTORC1 pathway due to GPD2 KO was rescued by DHAP supplementation. Conclusion: Overall, the GPD2-ether lipid-Akt axis is newly described for the control of cancer growth. DHAP supply, a non-bioenergetic process, may constitute an important role of mitochondria in cancer.


Assuntos
Glicerolfosfato Desidrogenase , Mitocôndrias , Neoplasias , Proteínas Proto-Oncogênicas c-akt , Metabolismo Energético , Éteres/metabolismo , Glicerolfosfato Desidrogenase/genética , Glicerolfosfato Desidrogenase/metabolismo , Mitocôndrias/enzimologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Camundongos , Neoplasias/enzimologia , Neoplasias/patologia , Humanos
20.
Blood Adv ; 7(13): 3155-3168, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-36809797

RESUMO

Acute myeloid leukemia (AML) generally has an unsatisfactory prognosis despite the recent introduction of new regimens, including targeted agents and antibodies. To find a new druggable pathway, we performed integrated bioinformatic pathway screening on large OHSU and MILE AML databases, discovered the SUMOylation pathway, and validated it independently with an external data set (totaling 2959 AML and 642 normal sample data). The clinical relevance of SUMOylation in AML was supported by its core gene expression which is correlated with patient survival, European LeukemiaNet 2017 risk classification, and AML-relevant mutations. TAK-981, a first-in-class SUMOylation inhibitor currently under clinical trials for solid tumors, showed antileukemic effects with apoptosis induction, cell-cycle arrest, and induction of differentiation marker expression in leukemic cells. It exhibited potent nanomolar activity, often stronger than that of cytarabine, which is part of the standard of care. TAK-981's utility was further demonstrated in in vivo mouse and human leukemia models as well as patient-derived primary AML cells. Our results also indicate direct and cancer cell-inherent anti-AML effects by TAK-981, different from the type 1 interferon and immune-dependent mechanism in a previous solid tumor study. Overall, we provide a proof-of-concept for SUMOylation as a new targetable pathway in AML and propose TAK-981 as a promising direct anti-AML agent. Our data should prompt studies on optimal combination strategies and transitions to clinical trials in AML.


Assuntos
Antineoplásicos , Leucemia Mieloide Aguda , Animais , Camundongos , Humanos , Apoptose , Sumoilação , Proliferação de Células , Antineoplásicos/uso terapêutico , Leucemia Mieloide Aguda/genética
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