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1.
Exerc Sport Sci Rev ; 50(3): 145-155, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35152237

RESUMO

Recent studies have greatly advanced our understanding of the central role of mitochondria on endothelial function. Here, we propose a hypothesis that unidirectional laminar (pulsatile) flow and disturbed laminar (oscillatory) flow may differentially modulate mitochondrial phenotypes in the context of their bioenergetic, signaling, and biosynthetic functions, providing novel insights into subcellular mechanisms underlying how exercise benefits the improvement of vascular health.


Assuntos
Células Endoteliais , Endotélio Vascular , Células Cultivadas , Humanos , Mitocôndrias , Estresse Mecânico
2.
Sensors (Basel) ; 21(9)2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33926052

RESUMO

This study describes the development of a landslide monitoring system for the purpose of reducing damages caused by landslides in natural terrain. The system was developed to analyze the effects of landslide-inducing rainfall and the behavior of slopes through 12 monitoring stations that are distributed across eight national parks in Korea. Several sensors and a data acquisition equipment to monitor landslide were installed in each station. The composition of the system and its operating program were designed to efficiently manage the sizeable amounts of real-time monitoring data that are collected from the various stations. To test the potential of the developed system for reliable landslide hazard evaluations, data measured over a five-year period by the two monitoring stations in Jirisan National Park were analyzed. Subsequently, the suction stress of the soil over the monitoring period was calculated by applying laboratory test result of the geotechnical and unsaturated soil properties in the analysis domain area. The infinite slope stability analysis combined with an effective stress concept based on the suction stress was applied to calculate the factor of safety. This method also enabled the temporal and quantitative evaluation of slope stability in natural terrain. In addition, based on the monitoring and slope stability analysis results, an analysis for the spatial classification of landslide hazards was conducted. The analysis results quantitatively and statistically demonstrated that 98% of historical landslide initiation areas were classified as high hazard levels.

3.
Circulation ; 140(14): 1205-1216, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31769940

RESUMO

Mitochondria have emerged as a central factor in the pathogenesis and progression of heart failure, and other cardiovascular diseases, as well, but no therapies are available to treat mitochondrial dysfunction. The National Heart, Lung, and Blood Institute convened a group of leading experts in heart failure, cardiovascular diseases, and mitochondria research in August 2018. These experts reviewed the current state of science and identified key gaps and opportunities in basic, translational, and clinical research focusing on the potential of mitochondria-based therapeutic strategies in heart failure. The workshop provided short- and long-term recommendations for moving the field toward clinical strategies for the prevention and treatment of heart failure and cardiovascular diseases by using mitochondria-based approaches.


Assuntos
Sistema Cardiovascular , Educação/métodos , Insuficiência Cardíaca/terapia , Mitocôndrias/fisiologia , National Heart, Lung, and Blood Institute (U.S.) , Relatório de Pesquisa , Pesquisa Biomédica/métodos , Pesquisa Biomédica/tendências , Sistema Cardiovascular/patologia , Educação/tendências , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Humanos , National Heart, Lung, and Blood Institute (U.S.)/tendências , Relatório de Pesquisa/tendências , Pesquisa Translacional Biomédica/métodos , Pesquisa Translacional Biomédica/tendências , Estados Unidos/epidemiologia
4.
Am J Physiol Heart Circ Physiol ; 318(6): H1559-H1569, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32383993

RESUMO

Cerebrovascular dysfunction is a critical risk factor for the pathogenesis of Alzheimer's disease (AD). The purinergic P2Y2 receptor and endoplasmic reticulum (ER) stress are tightly associated with vascular dysfunction and the pathogenesis of AD. However, the protective effects of exercise training on P2Y2 receptor- and ER stress-associated cerebrovascular dysfunction in AD are mostly unknown. Control (C57BL/6, CON) and AD (APP/PS1dE9, AD) mice underwent treadmill exercise training (EX). 2-MeS-ATP-induced dose-dependent vasoreactivity was determined by using a pressurized posterior cerebral artery (PCA) from 10-12-mo-old mice. Human brain microvascular endothelial cells (HBMECs) were exposed to laminar shear stress (LSS) at 20 dyn/cm2 for 30 min, 2 h, and 24 h. The expression of P2Y2 receptors, endothelial nitric oxide synthase (eNOS), and ER stress signaling were quantified by Western blot analysis. Notably, exercise converted ATP-induced vasoconstriction in the PCA from AD mice to vasodilation in AD+EX mice to a degree commensurate to the vascular reactivity observed in CON mice. Exercise reduced the expression of amyloid peptide precursor (APP) and increased the P2Y2 receptor and Akt/eNOS expression in AD mice brain. Mechanistically, LSS increased the expression of both P2Y2 receptor and eNOS protein in HBMECs, but these increases were blunted by a P2Y2 receptor antagonist in HBMECs. Exercise also reduced the expression of aberrant ER stress markers p-IRE1, p/t-eIF2α, and CHOP, as well as Bax/Bcl-2, in AD mice brain. Collectively, our results demonstrate for the first time that exercise mitigates cerebrovascular dysfunction in AD through modulating P2Y2 receptor- and ER stress-dependent endothelial dysfunction.NEW & NOTEWORTHY A limited study has investigated whether exercise training can improve cerebrovascular function in Alzheimer's disease. The novel findings of the study are that exercise training improves cerebrovascular dysfunction through enhancing P2Y2 receptor-mediated eNOS signaling and reducing ER stress-associated pathways in AD. These data suggest that exercise training, which regulates P2Y2 receptor and ER stress in AD brain, is a potential therapeutic strategy for Alzheimer's disease.


Assuntos
Doença de Alzheimer/metabolismo , Circulação Cerebrovascular/fisiologia , Estresse do Retículo Endoplasmático/fisiologia , Condicionamento Físico Animal/fisiologia , Receptores Purinérgicos P2Y2/metabolismo , Doença de Alzheimer/fisiopatologia , Animais , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Camundongos , Óxido Nítrico Sintase Tipo III/metabolismo , Artéria Cerebral Posterior/metabolismo , Artéria Cerebral Posterior/fisiopatologia , Proteínas Proto-Oncogênicas c-akt/metabolismo
5.
Anaerobe ; 64: 102236, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32623046

RESUMO

Clostridium perfringens is ubiquitous in the environment and the gastrointestinal tract of warm-blooded animals. While part of the gut microbiome, abnormal growth of C. perfringens causes histotoxic, neurologic, and enteric diseases in a variety of animal species, including humans, due to the production of toxins. There is extremely limited information on C. perfringens infection in non-human primates. Presently, 10 strains were successfully isolated from 126 monkeys and confirmed by molecular and biochemical analyses. All isolates were genotype A based on molecular analysis. Alpha toxin was identified in all isolates. Beta 2 toxin was detected in only three isolates. No other toxins, including enterotoxin, beta, iota, epsilon, and net B toxin, were identified in any isolate. All isolates were highly susceptible to ß-lactam antibiotics. Double hemolysis and lecithinase activity were commonly observed in all strains. Biofilm formation, which can increase antibiotic resistance, was identified in 90% of the isolates. The data are the first report the prevalence and characteristics of C. perfringens isolated from captive cynomolgus monkeys.


Assuntos
Toxinas Bacterianas/genética , Biofilmes/crescimento & desenvolvimento , Clostridium perfringens/efeitos dos fármacos , Clostridium perfringens/genética , Farmacorresistência Bacteriana Múltipla , Macaca fascicularis/microbiologia , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Infecções por Clostridium/microbiologia , Infecções por Clostridium/veterinária , Clostridium perfringens/isolamento & purificação , DNA Bacteriano/genética , Fezes/microbiologia , Feminino , Genótipo , Masculino , Filogenia , Prevalência , RNA Ribossômico 16S/genética , beta-Lactamas/farmacologia
6.
Nano Lett ; 19(11): 8333-8341, 2019 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-31657935

RESUMO

A group of chemotherapeutic drugs has gained increasing interest in cancer immunotherapy due to the potential to induce immunogenic cell death (ICD). A critical challenge in using the ICD inducers in cancer immunotherapy is the immunotoxicity accompanying their antiproliferative effects. To alleviate this, a nanocapsule formulation of carfilzomib (CFZ), an ICD-inducing proteasome inhibitor, was developed using interfacial supramolecular assembly of tannic acid (TA) and iron, supplemented with albumin coating. The albumin-coated CFZ nanocapsules (CFZ-pTA-alb) attenuated CFZ release, reducing toxicity to immune cells. Moreover, due to the adhesive nature of the TA assembly, CFZ-pTA-alb served as a reservoir of damage-associated molecular patterns released from dying tumor cells to activate dendritic cells. Upon intratumoral administration, CFZ-pTA-alb prolonged tumor retention of CFZ and showed consistently greater antitumor effects than cyclodextrin-solubilized CFZ (CFZ-CD) in B16F10 and CT26 tumor models. Unlike CFZ-CD, the locally injected CFZ-pTA-alb protected or enhanced CD8+ T cell population in tumors, helped develop splenocytes with tumor-specific interferon-γ response, and delayed tumor development on the contralateral side in immunocompetent mice (but not in athymic nude mice), supporting that CFZ-pTA-alb contributed to activating antitumor immunity. This study demonstrates that sustained delivery of ICD inducers by TA-based nanocapsules is an effective way of translating local ICD induction to systemic antitumor immunity.


Assuntos
Antineoplásicos/administração & dosagem , Nanocápsulas/química , Neoplasias/tratamento farmacológico , Oligopeptídeos/administração & dosagem , Taninos/química , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Preparações de Ação Retardada/química , Humanos , Imunidade/efeitos dos fármacos , Morte Celular Imunogênica/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/imunologia , Oligopeptídeos/uso terapêutico
7.
Int J Mol Sci ; 21(9)2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32384696

RESUMO

Alzheimer's disease is the most common neurodegenerative brain disease causing dementia. It is characterized by slow onset and gradual worsening of memory and other cognitive functions. Recently, parabiosis and infusion of plasma from young mice have been proposed to have positive effects in aging and Alzheimer's disease. Therefore, this study examined whether infusion of plasma from exercised mice improved cognitive functions related to the hippocampus in a 3xTg-Alzheimer's disease (AD) model. We collected plasma from young mice that had exercised for 3 months and injected 100 µL of plasma into the tail vein of 12-month-old 3xTg-AD mice 10 times at 3-day intervals. We then analyzed spatial learning and memory, long-term memory, hippocampal GSK3ß/tau proteins, synaptic proteins, mitochondrial function, apoptosis, and neurogenesis. In the hippocampus of 3xTg-AD mice, infusion of plasma from exercised mice improved neuroplasticity and mitochondrial function and suppressed apoptosis, ultimately improving cognitive function. However, there was no improvement in tau hyperphosphorylation. This study showed that plasma from exercised mice could have a protective effect on cognitive dysfunction and neural circuits associated with AD via a tau-independent mechanism involving elevated brain-derived neurotrophic factor due to exercise.


Assuntos
Disfunção Cognitiva/terapia , Hipocampo/metabolismo , Condicionamento Físico Animal/métodos , Troca Plasmática/métodos , Animais , Apoptose , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipocampo/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Plasticidade Neuronal , Proteínas tau/metabolismo
8.
Mol Pharm ; 16(5): 1864-1873, 2019 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-30916974

RESUMO

Tumor microenvironment is a significant physical barrier to the effective delivery of chemotherapy into solid tumors. To overcome this challenge, tumors are pretreated with an agent that reduces cellular and extracellular matrix densities prior to chemotherapy. However, it also comes with a concern that metastasis may increase due to the loss of protective containment. We hypothesize that timely priming at the early stage of primary tumors will help control metastasis. To test this, we primed orthotopic 4T1 breast tumors with a paclitaxel (PTX)-loaded iron-oxide-decorated poly(lactic- co-glycolic acid) nanoparticle (NP) composite (PTX@PINC), which can be quickly concentrated in target tissues with the aid of an external magnet, and monitored its effect on the delivery of subsequently administered NPs. Magnetic resonance imaging and optical whole-body imaging confirmed that PTX@PINC was efficiently delivered to tumors by the external magnet and help loosen the tumors to accommodate subsequently delivered NPs. Consistently, the primed tumors responded to Doxil better than nonprimed tumors. In addition, lung metastasis was significantly reduced in the animals PINC-primed prior to Doxil administration. These results support that PINC combined with magnetophoresis can facilitate the timely management of primary tumors with a favorable secondary effect on metastasis.


Assuntos
Antibióticos Antineoplásicos/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/secundário , Doxorrubicina/análogos & derivados , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas de Magnetita/administração & dosagem , Paclitaxel/uso terapêutico , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/farmacologia , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Feminino , Compostos Férricos/química , Injeções Intravenosas , Nanopartículas de Magnetita/química , Camundongos , Camundongos Endogâmicos BALB C , Paclitaxel/administração & dosagem , Paclitaxel/química , Paclitaxel/farmacologia , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/farmacologia , Polietilenoglicóis/uso terapêutico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
9.
J Physiol ; 596(18): 4413-4426, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30099751

RESUMO

KEY POINTS: Referring to the muscle memory theory, previously trained muscles acquire strength and volume much faster than naive muscles. Using extreme experimental models such as synergist ablation or steroid administration, previous studies have demonstrated that the number of nuclei increases when a muscle becomes enlarged, which serves as a cellular muscle memory mechanism for the muscle. In the present study, we found that, when rats were subjected to physiologically relevant resistance training, the number of myonuclei increased and was retained during a long-term detraining period. The acquired myonuclei were related to a greater degree of muscle hypertrophic and mitochondrial biogenesis processes following subsequent hypertrophic conditions. Our data suggest a cellular mechanism supporting the notion that exposing young muscles to resistance training would help to restore age-related muscle loss coupled with mitochondrial dysfunction in later life. ABSTRACT: Muscle hypertrophy induced by resistance training is accompanied by an increase in the number of myonuclei. The acquired myonuclei are viewed as a cellular component of muscle memory by which muscle enlargement is promoted during a re-training period. In the present study, we investigated the effect of exercise preconditioning on mitochondrial remodelling induced by resistance training. Sprague-Dawley rats were divided into four groups: untrained control, training, pre-training or re-training. The training groups were subjected to weight loaded-ladder climbing exercise training. Myonuclear numbers were significantly greater (up to 20%) in all trained muscles compared to untrained controls. Muscle mass was significantly higher in the re-training group compared to the training group (∼2-fold increase). Mitochondrial content, mitochondrial biogenesis gene expression levels and mitochondrial DNA copy numbers were significantly higher in re-trained muscles compared to the others. Oxidative myofibres (type I) were significantly increased only in the re-trained muscles. Furthermore, in vitro studies using insulin-like growth factor-1-treated L6 rat myotubes demonstrated that myotubes with a higher myonuclear number confer greater expression levels of both mitochondrial and nuclear genes encoding for constitutive and regulatory mitochondrial proteins, which also showed a greater mitochondrial respiratory function. These data suggest that myonuclei acquired from previous training facilitate mitochondrial biogenesis in response to subsequent retraining by (at least in part) enhancing cross-talk between mitochondria and myonuclei in the pre-conditioned myofibres.


Assuntos
Mitocôndrias Musculares/metabolismo , Fibras Musculares Esqueléticas/fisiologia , Biogênese de Organelas , Condicionamento Físico Animal , Animais , Núcleo Celular/metabolismo , DNA Mitocondrial/genética , Feminino , Fibras Musculares Esqueléticas/metabolismo , Força Muscular , Ratos , Ratos Sprague-Dawley
10.
Small ; 14(16): e1703670, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29570231

RESUMO

Nanoparticulate drug carriers exploit the enhanced permeability of tumor vasculature to achieve selective delivery of chemotherapeutic drugs. For this purpose, nanoparticles (NPs) need to circulate with a long half-life, enter tumors via the permeable vasculature and stay in tumors via favorable interactions with tumor cells. To fulfill these requirements, albumin-coated nanocrystal formulation of paclitaxel (PTX), Cim-F-alb, featuring high drug loading content, physical stability in serum, and surface-bound albumin in its native conformation is prepared. The pharmacokinetic and biodistribution (PK/BD) profiles of Cim-F-alb in a mouse model of B16F10 melanoma show that Cim-F-alb exhibits a longer plasma half-life and a greater PTX deposition in tumors than Abraxane by ≈1.5 and ≈4.6 fold, respectively. Biolayer interferometry analysis indicates that Cim-F-alb has less interaction with serum proteins than nanocrystals lacking albumin coating, indicating the protective effect of the surface-bound albumin against opsonization in the initial deposition phase. With the advantageous PK/BD profiles, Cim-F-alb shows greater and longer-lasting anticancer efficacy than Abraxane at the equivalent dose. This study demonstrates the significance of controlling circulation stability and surface property of NPs in efficient drug delivery to tumors and enhanced anticancer efficacy.


Assuntos
Paclitaxel Ligado a Albumina/metabolismo , Paclitaxel Ligado a Albumina/farmacocinética , Nanopartículas/química , Nanopartículas/metabolismo , Animais , Portadores de Fármacos/metabolismo , Portadores de Fármacos/farmacocinética , Masculino , Melanoma/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
11.
Mol Pharm ; 2018 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-29341617

RESUMO

Intravenous delivery of poorly water-soluble anticancer drugs such as docetaxel (DTX) is challenging due to the low bioavailability and the toxicity related to solubilizing excipients. Colloidal nanoparticles are used as alternative carriers, but low drug loading capacity and circulation instability limit their clinical translation. To address these challenges, DTX nanocrystals (NCs) were prepared using Pluronic F127 as an intermediate stabilizer and albumin as a functional surface modifier, which were previously found to be effective in producing small and stable NCs. We hypothesize that the albumin-coated DTX NCs (DTX-F-alb) will remain stable in serum-containing medium so as to effectively leverage the enhanced permeability and retention effect. In addition, the surface-bound albumin, in its native form, may contribute to cellular transport of NCs through interactions with albumin-binding proteins such as secreted protein acidic and rich in cysteine (SPARC). DTX-F-alb NCs showed sheet-like structure with an average length, width, and thickness of 284 ± 96, 173 ± 56, and 40 ± 8 nm and remained stable in 50% serum solution at a concentration greater than 10 µg/mL. Cytotoxicity and cellular uptake of DTX-F-alb and unformulated (free) DTX were compared on three cell lines with different levels of SPARC expression and DTX sensitivity. While the uptake of free DTX was highly dependent on DTX sensitivity, DTX-F-alb treatment resulted in relatively consistent cellular levels of DTX. Free DTX was more efficient in entering drug-sensitive B16F10 and SKOV-3 cells than DTX-F-alb, with consistent cytotoxic effects. In contrast, multidrug-resistant NCI/ADR-RES cells took up DTX-F-alb more than free DTX with time and responded better to the former. This difference was reduced by SPARC knockdown. The high SPARC expression level of NCI/ADR-RES cells, the known affinity of albumin for SPARC, and the opposing effect of SPARC knockdown support that DTX-F-alb have exploited the surface-bound albumin-SPARC interaction in entering NCI/ADR-RES cells. Albumin-coated NC system is a promising formulation for the delivery of hydrophobic anticancer drugs to multidrug-resistant tumors.

12.
N Engl J Med ; 368(11): 1027-32, 2013 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-23484829

RESUMO

There is growing evidence that alterations in metabolism may contribute to tumorigenesis. Here, we report on members of families with the Li-Fraumeni syndrome who carry germline mutations in TP53, the gene encoding the tumor-suppressor protein p53. As compared with family members who are not carriers and with healthy volunteers, family members with these mutations have increased oxidative phosphorylation of skeletal muscle. Basic experimental studies of tissue samples from patients with the Li-Fraumeni syndrome and a mouse model of the syndrome support this in vivo finding of increased mitochondrial function. These results suggest that p53 regulates bioenergetic homeostasis in humans. (Funded by the National Heart, Lung, and Blood Institute and the National Institutes of Health; ClinicalTrials.gov number, NCT00406445.).


Assuntos
Metabolismo Energético/genética , Exercício Físico/fisiologia , Genes p53 , Síndrome de Li-Fraumeni/metabolismo , Mitocôndrias Musculares/metabolismo , Fosfocreatina/metabolismo , Animais , Estudos de Casos e Controles , Modelos Animais de Doenças , Feminino , Mutação em Linhagem Germinativa , Heterozigoto , Humanos , Síndrome de Li-Fraumeni/genética , Masculino , Camundongos , Músculo Esquelético/metabolismo , Consumo de Oxigênio/genética , Consumo de Oxigênio/fisiologia , Projetos Piloto , Levantamento de Peso/fisiologia
13.
Am J Physiol Heart Circ Physiol ; 309(3): H425-33, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26024684

RESUMO

The concept of enhancing structural integrity of mitochondria has emerged as a novel therapeutic option for cardiovascular disease. Flow-induced increase in laminar shear stress is a potent physiological stimulant associated with exercise, which exerts atheroprotective effects in the vasculature. However, the effect of laminar shear stress on mitochondrial remodeling within the vascular endothelium and its related functional consequences remain largely unknown. Using in vitro and in vivo complementary studies, here, we report that aerobic exercise alleviates the release of endothelial microparticles in prehypertensive individuals and that these salutary effects are, in part, mediated by shear stress-induced mitochondrial biogenesis. Circulating levels of total (CD31(+)/CD42a(-)) and activated (CD62E(+)) microparticles released by endothelial cells were significantly decreased (∼40% for both) after a 6-mo supervised aerobic exercise training program in individuals with prehypertension. In cultured human endothelial cells, laminar shear stress reduced the release of endothelial microparticles, which was accompanied by an increase in mitochondrial biogenesis through a sirtuin 1 (SIRT1)-dependent mechanism. Resveratrol, a SIRT1 activator, treatment showed similar effects. SIRT1 knockdown using small-interfering RNA completely abolished the protective effect of shear stress. Disruption of mitochondrial integrity by either antimycin A or peroxisome proliferator-activated receptor-γ coactivator-1α small-interfering RNA significantly increased the number of total, and activated, released endothelial microparticles, and shear stress restored these back to basal levels. Collectively, these data demonstrate a critical role of endothelial mitochondrial integrity in preserving endothelial homeostasis. Moreover, prolonged laminar shear stress, which is systemically elevated during aerobic exercise in the vessel wall, mitigates endothelial dysfunction by promoting mitochondrial biogenesis.


Assuntos
Micropartículas Derivadas de Células/metabolismo , Exercício Físico , Células Endoteliais da Veia Umbilical Humana/metabolismo , Renovação Mitocondrial , Pré-Hipertensão/metabolismo , Selectina E/genética , Selectina E/metabolismo , Feminino , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Complexo Glicoproteico GPIb-IX de Plaquetas/genética , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Pré-Hipertensão/sangue , Fluxo Sanguíneo Regional , Resveratrol , Sirtuína 1/genética , Sirtuína 1/metabolismo , Estilbenos/farmacologia , Estresse Mecânico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
Ethn Dis ; 25(4): 413-8, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-26674844

RESUMO

BACKGROUND: African Americans have a predisposition to heightened systemic inflammation and a high prevalence of hypertension. OBJECTIVE: The purpose of this study was to evaluate the influence of interleukin-10 (IL-10) and laminar shear stress (LSS) on African American endothelial cells by measuring total endothelial nitric oxide synthase (eNOS) protein expression and its phosphorylated form (p-eNOS) at Serine 1177, and nitric oxide (NO) levels, in response to IL-10 incubation and high physiological levels of LSS, used as an in vitro mimetic for aerobic exercise training (AEXT). DESIGN: Human umbilical vein endothelial cells (HUVEC) from an African American donor were cultured. The experimental conditions included Static, Static with IL-10 Incubation, LSS at 20 dynes/cm², and LSS at 20 dynes/cm² with IL-10 Incubation. Western blotting was used to measure eNOS and p-eNOS protein expression in the cells. A modified Griess assay was used to measure NO metabolites in the cell culture media. RESULTS: There were significant increases in p-eNOS, eNOS, and NO in the LSS at 20 dynes/cm² and LSS at 20 dynes/cm² with IL-10 Incubation experimental conditions when compared to the Static experimental condition. There were no other statistically significant differences demonstrating that IL-10 did not have an additive effect on eNOS activity in our study. CONCLUSION: The significant increases in p-eNOS, eNOS, and NO as a result of LSS in African American HUVECs suggest that AEXT may be a viable, nonpharmacologic method to improve vascular inflammation status and vasodilation, and thereby contribute to hypertension reduction in the African American population.


Assuntos
Negro ou Afro-Americano , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Interleucina-10/farmacologia , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico/metabolismo , Estresse Mecânico , Técnicas de Cultura de Células , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Resistência ao Cisalhamento
15.
Am J Physiol Regul Integr Comp Physiol ; 305(8): R927-38, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23904108

RESUMO

Mitochondria are dynamic organelles forming a tubular network that is continuously fusing and dividing to control their morphology and functions. Recent literature has shed new light on a potential link between the dynamic behavior of mitochondria and muscle development. In this study, we investigate the role of mitochondrial fission factor dynamin-related protein 1 (Drp1) in myogenic differentiation. We found that differentiation of C2C12 myoblasts induced by serum starvation was accompanied by a gradual increase in Drp1 protein expression (to ∼350% up to 3 days) and a fast reduction of Drp1 phosphorylation at Ser-637 (to ∼30%) resulting in translocation of Drp1 protein from the cytosol to mitochondria. During differentiation, treatment of myoblasts with mitochondrial division inhibitor (mdivi-1), a specific inhibitor of Drp1 GTPase activity, caused extensive formation of elongated mitochondria, which coincided with increased apoptosis evidenced by both enhanced caspase-3 activity and increased number of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells. Furthermore, the mdivi-1-treated myotubes (day 3 in differentiation media) showed a reduction in mitochondrial DNA content, mitochondrial mass, and membrane potential in a dose-dependent manner indicating defects in mitochondrial biogenesis during myogenic differentiation. Most interestingly, mdivi-1 treatment significantly suppressed myotube formation in both C2C12 cells and primary myoblasts. Likewise, stable overexpression of a dominant negative mutant Drp1 (K38A) dramatically reduced myogenic differentiation. These data suggest that Drp-1-dependent mitochondrial division is a necessary step for successful myogenic differentiation, and perturbation of mitochondrial dynamics hinders normal mitochondrial adaptations during muscle development. Therefore, in the present study, we report a novel physiological role of mitochondrial dynamics in myogenic differentiation.


Assuntos
Proteínas Quinases Associadas com Morte Celular/metabolismo , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/fisiologia , Desenvolvimento Muscular/fisiologia , Mioblastos/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Caspase 3/metabolismo , Linhagem Celular , Proteínas Quinases Associadas com Morte Celular/genética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/fisiologia , Camundongos , Mitocôndrias/efeitos dos fármacos , Dinâmica Mitocondrial/efeitos dos fármacos , Desenvolvimento Muscular/efeitos dos fármacos , Mioblastos/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Quinazolinonas/farmacologia
16.
Mol Pharm ; 10(6): 2093-110, 2013 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-23461379

RESUMO

Nanoparticles have received enormous attention as a promising tool to enhance target-specific drug delivery and diagnosis. Various in vitro and in vivo techniques are used to characterize a new system and predict its clinical efficacy. These techniques enable efficient comparison across nanoparticles and facilitate a product optimization process. On the other hand, we recognize their limitations as a prediction tool, due to inadequate applications and overly simplified test conditions. We provide a critical review of in vitro and in vivo techniques currently used for evaluation of nanoparticles and introduce emerging techniques and models that may be used complementarily.


Assuntos
Nanomedicina/métodos , Nanopartículas/química , Animais , Cromatografia em Gel , Transferência Ressonante de Energia de Fluorescência , Humanos , Temperatura
17.
Biomacromolecules ; 14(7): 2389-95, 2013 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-23738975

RESUMO

Nanometer-sized drug carriers including polymeric nanoparticles (NPs) have been used to increase biodistribution of a drug in tumors, thereby reducing the effective dose of chemotherapy. NPs increase drug delivery to tumors to a certain extent, but the amount reaching tumors is only a small fraction of the total administered NPs because they depend on passive accumulation via the leaky vasculature surrounding tumors. In an attempt to further increase the drug delivery to tumors, we develop a polymeric NP system that interacts with an endothelial tumor marker. The NPs are decorated with quinic acid, a synthetic mimic of sialyl Lewis-x, which binds to E-selectin, overexpressed on the surface of endothelial cells surrounding solid tumors. The NPs selectively bind to endothelial cells activated with tumor necrosis factor-α, with weak affinity at a relatively high shear stress. These properties may help NPs reach tumors by increasing the encounter of NPs with the peritumoral endothelium without hindering subsequent transport of the NPs.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/química , Portadores de Fármacos/química , Nanopartículas/química , Neoplasias/tratamento farmacológico , Ácido Quínico/química , Linhagem Celular Tumoral , Selectina E/química , Células HL-60 , Células Endoteliais da Veia Umbilical Humana/química , Humanos
18.
Pharm Res ; 30(8): 1956-67, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23609560

RESUMO

PURPOSE: To create poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs), where a drug-encapsulating NP core is covered with polyethylene glycol (PEG) in a normal condition but exposes a cell-interactive TAT-modified surface in an environment rich in matrix metalloproteinases (MMPs). METHODS: PLGA NPs were modified with TAT peptide (PLGA-pDA-TAT NPs) or dual-modified with TAT peptide and a conjugate of PEG and MMP-substrate peptide (peritumorally activatable NPs, PANPs) via dopamine polymerization. Cellular uptake of fluorescently labeled NPs was observed with or without a pre-treatment of MMP-2 by confocal microscopy and flow cytometry. NPs loaded with paclitaxel (PTX) were tested against SKOV-3 ovarian cancer cells to evaluate the contribution of surface modification to cellular delivery of PTX. RESULTS: While the size and morphology did not significantly change due to the modification, NPs modified with dopamine polymerization were recognized by their dark color. TAT-containing NPs (PLGA-pDA-TAT NPs and PANPs) showed changes in surface charge, indicative of effective conjugation of TAT peptide on the surface. PLGA-pDA-TAT NPs and MMP-2-pre-treated PANPs showed relatively good cellular uptake compared to PLGA NPs, MMP-2-non-treated PANPs, and NPs with non-cleavable PEG. After 3 h treatment with cells, PTX loaded in cell-interactive NPs showed greater toxicity than non-interactive ones as the former could enter cells during the incubation period. However, due to the initial burst drug release, the difference was not as clear as microscopic observation. CONCLUSIONS: PEGylated polymeric NPs that could expose cell-interactive surface in response to MMP-2 were successfully created by dual modification of PLGA NPs using dopamine polymerization.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Portadores de Fármacos/química , Indóis/química , Ácido Láctico/química , Nanopartículas/química , Paclitaxel/administração & dosagem , Ácido Poliglicólico/química , Polímeros/química , Sequência de Aminoácidos , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Portadores de Fármacos/metabolismo , Feminino , Produtos do Gene tat/química , Produtos do Gene tat/metabolismo , Humanos , Indóis/metabolismo , Ácido Láctico/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Dados de Sequência Molecular , Nanopartículas/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Paclitaxel/farmacologia , Peptídeos/química , Peptídeos/metabolismo , Polietilenoglicóis/química , Polietilenoglicóis/metabolismo , Ácido Poliglicólico/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros/metabolismo
19.
Technol Cancer Res Treat ; 22: 15330338231170939, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37132029

RESUMO

Cancer disease has outgrown a life-threatening disease. Having reference to preceding reports provided by the International Agency for Research on Cancer, an estimated 9.6 million deaths transpired from cancer worldwide in 2018. Similarly, about 18.1 million new cases of cancer are being reported. The rise in conventional treatments akin to surgeries, chemotherapies, and radiotherapies was enormously observed to eradicate cancer tumors. These studies have shown unfavorable side effects in clinical treatments. Drug resistivity and drug cytotoxicities are also major issues to overcome. Considering these, researchers are developing alternative methods that are robust, economical, and safe. The use of light for therapeutic purposes shows a great history in vitiligo treatment. The combination of an effective activating agent and phototherapy could result as the best alternative with a great outcome to minimize adverse effects on healthy tissues. The utilization of light in the deletion of tumors using photothermal agents, and photosensitizers, hence the phototherapies in oncology were discovered and rapidly involved in the advancement of clinical approach. Here, in this article, we tried to highlight the recent trends in phototherapy and reviewed different types of phototherapy methods in cancer treatments and their latest clinical, preclinical, and in vivo studies.


Assuntos
Neoplasias , Fototerapia , Humanos , Neoplasias/terapia , Fármacos Fotossensibilizantes
20.
NPJ Biofilms Microbiomes ; 9(1): 83, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907565

RESUMO

Sea urchins are biotic factors driving the decline of kelp forests in marine ecosystems. However, few studies have analyzed the microbiota of surviving sea urchins in barren regions with scarce diet resources. Here, we analyzed the microbiota in the pharynx and gut of the sea urchin Mesocentrotus nudus located along the coast of an expanding barren region in South Korea. The ecological adaptation of genera in sea urchins was predicted using the neutral assembly model. The pharynx and gut microbiota were different, and microbes in the surrounding habitats dispersed more to the pharynx than to the gut. The gut microbiota in sea urchins is altered by barren severity and plays different roles in host energy metabolism. These findings help to understand the microbiota in sea urchins according to urchin barren and its contribution to the survival of sea urchins in severe barren regions with limited macroalgae.


Assuntos
Kelp , Microbiota , Animais , Cadeia Alimentar , Ouriços-do-Mar
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