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1.
Brain Behav Immun Health ; 32: 100675, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37600600

RESUMO

The COVID-19 pandemic has resulted in significant morbidity and mortality worldwide. Management of the pandemic has relied mainly on SARS-CoV-2 vaccines, while alternative approaches such as meditation, shown to improve immunity, have been largely unexplored. Here, we probe the relationship between meditation and COVID-19 disease and directly test the impact of meditation on the induction of a blood environment that modulates viral infection. We found a significant inverse correlation between length of meditation practice and SARS-CoV-2 infection as well as accelerated resolution of symptomology of those infected. A meditation "dosing" effect was also observed. In cultured human lung cells, blood from experienced meditators induced factors that prevented entry of pseudotyped viruses for SARS-CoV-2 spike protein of both the wild-type Wuhan-1 virus and the Delta variant. We identified and validated SERPINA5, a serine protease inhibitor, as one possible protein factor in the blood of meditators that is necessary and sufficient for limiting pseudovirus entry into cells. In summary, we conclude that meditation can enhance resiliency to viral infection and may serve as a possible adjuvant therapy in the management of the COVID-19 pandemic.

2.
J Adv Res ; 31: 35-47, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34194831

RESUMO

Introduction: Incidents of myocardial infarction and sudden cardiac arrest vary with time of the day, but the mechanism for this effect is not clear. We hypothesized that diurnal changes in the ability of cardiac mitochondria to control calcium homeostasis dictate vulnerability to cardiovascular events. Objectives: Here we investigate mitochondrial calcium dynamics, respiratory function, and reactive oxygen species (ROS) production in mouse heart during different phases of wake versus sleep periods. Methods: We assessed time-of-the-day dependence of calcium retention capacity of isolated heart mitochondria from young male C57BL6 mice. Rhythmicity of mitochondrial-dependent oxygen consumption, ROS production and transmembrane potential in homogenates were explored using the Oroboros O2k Station equipped with a fluorescence detection module. Changes in expression of essential clock and calcium dynamics genes/proteins were also determined at sleep versus wake time points. Results: Our results demonstrate that cardiac mitochondria exhibit higher calcium retention capacity and higher rates of calcium uptake during sleep period. This was associated with higher expression of clock gene Bmal1, lower expression of per2, greater expression of MICU1 gene (mitochondrial calcium uptake 1), and lower expression of the mitochondrial transition pore regulator gene cyclophilin D. Protein levels of mitochondrial calcium uniporter (MCU), MICU2, and sodium/calcium exchanger (NCLX) were also higher at sleep onset relative to wake period. While complex I and II-dependent oxygen utilization and transmembrane potential of cardiac mitochondria were lower during sleep, ROS production was increased presumably due to mitochondrial calcium sequestration. Conclusions: Taken together, our results indicate that retaining mitochondrial calcium in the heart during sleep dissipates membrane potential, slows respiratory activities, and increases ROS levels, which may contribute to increased vulnerability to cardiac stress during sleep-wake transition. This pronounced daily oscillations in mitochondrial functions pertaining to stress vulnerability may at least in part explain diurnal prevalence of cardiac pathologies.


Assuntos
Cálcio/metabolismo , Ritmo Circadiano , Mitocôndrias Cardíacas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sono , Fatores de Transcrição ARNTL/genética , Animais , Canais de Cálcio/genética , Proteínas de Ligação ao Cálcio/genética , Expressão Gênica , Humanos , Peróxido de Hidrogênio/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias Cardíacas/genética , Proteínas de Transporte da Membrana Mitocondrial/genética , Miocárdio/metabolismo , Fenômenos Fisiológicos Respiratórios
3.
FASEB J ; 35(3): e21407, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33583084

RESUMO

The obesity epidemic has increased type II diabetes mellitus (T2DM) across developed countries. Cardiac T2DM risks include ischemic heart disease, heart failure with preserved ejection fraction, intolerance to ischemia-reperfusion (I-R) injury, and refractoriness to cardioprotection. While opioids are cardioprotective, T2DM causes opioid receptor signaling dysfunction. We tested the hypothesis that sustained opioid receptor stimulus may overcome diabetes mellitus-induced cardiac dysfunction via membrane/mitochondrial-dependent protection. In a murine T2DM model, we investigated effects of morphine on cardiac function, I-R tolerance, ultrastructure, subcellular cholesterol expression, mitochondrial protein abundance, and mitochondrial function. T2DM induced 25% weight gain, hyperglycemia, glucose intolerance, cardiac hypertrophy, moderate cardiac depression, exaggerated postischemic myocardial dysfunction, abnormalities in mitochondrial respiration, ultrastructure and Ca2+ -induced swelling, and cell death were all evident. Morphine administration for 5 days: (1) improved glucose homeostasis; (2) reversed cardiac depression; (3) enhanced I-R tolerance; (4) restored mitochondrial ultrastructure; (5) improved mitochondrial function; (6) upregulated Stat3 protein; and (7) preserved membrane cholesterol homeostasis. These data show that morphine treatment restores contractile function, ischemic tolerance, mitochondrial structure and function, and membrane dynamics in type II diabetic hearts. These findings suggest potential translational value for short-term, but high-dose morphine administration in diabetic patients undergoing or recovering from acute ischemic cardiovascular events.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Mitocôndrias Cardíacas/efeitos dos fármacos , Morfina/farmacologia , Infarto do Miocárdio/tratamento farmacológico , Animais , Humanos , Camundongos , Mitocôndrias Cardíacas/metabolismo , Infarto do Miocárdio/etiologia , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
4.
Lab Chip ; 21(5): 904-915, 2021 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-33438699

RESUMO

Asymmetric surface acoustic waves have been shown useful in separating particles and cells in many microfluidics designs, mostly notably sessile microdroplets. However, no one has successfully extracted target particles or cells for later use from such samples. We present a novel omnidirectional spiral surface acoustic wave (OSSAW) design that exploits a new cut of lithium niobate, 152 Y-rotated, to rapidly rotate a microliter sessile drop to ∼10 g, producing efficient multi-size particle separation. We further extract the separated particles for the first time, demonstrating the ability to target specific particles, for example, platelets from mouse blood for further integrated point-of-care diagnostics. Within ∼5 s of surface acoustic wave actuation, particles with diameter of 5 µm and 1 µm can be separated into two portions with a purity of 83% and 97%, respectively. Red blood cells and platelets within mouse blood are further demonstrated to be separated with a purity of 93% and 84%, respectively. These advancements potentially provide an effective platform for whole blood separation and point-of-care diagnostics without need for micro or nanoscale fluidic enclosures.


Assuntos
Microfluídica , Som , Animais , Separação Celular , Camundongos
5.
J Endocrinol ; 224(1): 75-84, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25453115

RESUMO

Results from previous investigations have indicated that glucose-stimulated insulin secretion (GSIS) is affected by changes in cholesterol and its intermediates, but the precise link between secretion and cholesterol has not been thoroughly investigated. In this study, we show the contribution of both protein isoprenylation and cholesterol-dependent plasma membrane structural integrity to insulin secretion in INS-1E cells and mouse islets. Acute (2 h) inhibition of hydroxyl-methylglutaryl-CoA reductase by simvastatin (SIM) resulted in inhibition of GSIS without reduction in total cellular cholesterol content. This effect was prevented by cell loading with the isoprenyl molecule geranylgeranyl pyrophosphate. Chronic (24 h) inhibition of cholesterol biosynthesis resulted in inhibition of GSIS with a significant reduction in total cellular cholesterol content, which was also observed after the inhibition of cholesterol biosynthesis downstream of isoprenoid formation. Electron paramagnetic resonance analyses of INS-1E cells showed that the SIM-induced reduction in cholesterol increased plasma membrane fluidity. Thus, the blockade of cholesterol biosynthesis resulted in the reduction of availability of isoprenoids, followed by a reduction in the total cholesterol content associated with an increase in plasma membrane fluidity. Herein, we show the different contributions of cholesterol biosynthesis to GSIS, and propose that isoprenoid molecules and cholesterol-dependent signaling are dual regulators of proper ß-cell function.


Assuntos
Colesterol/biossíntese , Insulina/metabolismo , Animais , Anticolesterolemiantes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Células Cultivadas , Glucose/farmacologia , Secreção de Insulina , Fluidez de Membrana/efeitos dos fármacos , Microdomínios da Membrana/efeitos dos fármacos , Microdomínios da Membrana/metabolismo , Redes e Vias Metabólicas/efeitos dos fármacos , Redes e Vias Metabólicas/fisiologia , Camundongos , Fosfatos de Poli-Isoprenil/farmacologia , Sinvastatina/farmacologia , Ácidos Tricarboxílicos/farmacologia
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