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1.
Rep Prog Phys ; 87(8)2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39077989

RESUMO

Modern theories of phase transitions and scale invariance are rooted in path integral formulation and renormalization groups (RGs). Despite the applicability of these approaches in simple systems with only pairwise interactions, they are less effective in complex systems with undecomposable high-order interactions (i.e. interactions among arbitrary sets of units). To precisely characterize the universality of high-order interacting systems, we propose a simplex path integral and a simplex RG (SRG) as the generalizations of classic approaches to arbitrary high-order and heterogeneous interactions. We first formalize the trajectories of units governed by high-order interactions to define path integrals on corresponding simplices based on a high-order propagator. Then, we develop a method to integrate out short-range high-order interactions in the momentum space, accompanied by a coarse graining procedure functioning on the simplex structure generated by high-order interactions. The proposed SRG, equipped with a divide-and-conquer framework, can deal with the absence of ergodicity arising from the sparse distribution of high-order interactions and can renormalize a system with intertwined high-order interactions at thep-order according to its properties at theq-order (p⩽q). The associated scaling relation and its corollaries provide support to differentiate among scale-invariant, weakly scale-invariant, and scale-dependent systems across different orders. We validate our theory in multi-order scale-invariance verification, topological invariance discovery, organizational structure identification, and information bottleneck analysis. These experiments demonstrate the capability of our theory to identify intrinsic statistical and topological properties of high-order interacting systems during system reduction.

2.
Chaos ; 34(8)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39088345

RESUMO

How do heterogeneous individual behaviors arise in response to sudden events and how do they shape large-scale social dynamics? Based on a five-year naturalistic observation of individual purchasing behaviors, we extract the long-term consumption dynamics of diverse commodities from approximately 2.2 million purchase orders. We subdivide the consumption dynamics into trend, seasonal, and random components and analyze them using a renormalization group. We discover that the coronavirus pandemic, a sudden event acting on the social system, regulates the scaling and criticality of consumption dynamics. On a large time scale, the long-term dynamics of the system, regardless of arising from trend, seasonal, or random individual behaviors, is pushed toward a quasi-critical region between independent (i.e., the consumption behaviors of different commodities are irrelevant) and correlated (i.e., the consumption behaviors of different commodities are interrelated) phases as the pandemic erupts. On a small time scale, short-term consumption dynamics exhibits more diverse responses to the pandemic. While the trend and random behaviors of individuals are driven to quasi-criticality and exhibit scale-invariance as the pandemic breaks out, seasonal behaviors are more robust against regulations. Overall, these discoveries provide insights into how quasi-critical macroscopic dynamics emerges in heterogeneous social systems to enhance system reactivity to sudden events while there may exist specific system components maintaining robustness as a reflection of system stability.


Assuntos
COVID-19 , Pandemias , Humanos , COVID-19/epidemiologia , SARS-CoV-2
3.
Molecules ; 29(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38731449

RESUMO

Cannabis sativa L. (hemp) is a herbaceous plant rich in cannabinoids with a long history of use in pain treatment. The most well-characterized cannabinoids, cannabidiol (CBD) and Δ9-tetrahydrocannabinol (Δ9-THC), garnered much attention in chemotherapy-induced peripheral neuropathy (CIPN) treatment. However, few studies have investigated the biological benefits and mechanism of hemp extract on CIPN. In the present study, hemp extract (JG) rich in cannabinoids was extracted by supercritical fluid carbon dioxide extraction (SFCE). The antinociceptive efficacy was evaluated using a paclitaxel-induced peripheral neuropathy (PIPN) rat model based on behavioral tests. Further omics-based approaches were applied to explore the potential mechanisms. The results showed that JG decreased mechanical allodynia, thermal hyperalgesia, and inflammatory cytokines in PIPN rats significantly. Transcriptome analysis identified seven key genes significantly regulated by JG in PIPN model rats, mainly related to the neuroactive ligand-receptor interaction pathway, PPAR signaling pathway, and cAMP signaling pathway. In metabolomic analysis, a total of 39 significantly altered metabolites were identified, mainly correlated with pentose and glucuronate interconversions and the glycerophospholipid metabolism pathway. Gut microbiota analysis suggested that increased community Lachnoclostridium and Lachnospiraceae_UCG-006 in PIPN rats can be reversed significantly by JG. In conclusion, hemp extract exhibited antinociceptive effects on PIPN. The analgesic mechanism was probably related to the regulation of inflammation, neuroactive ligand-receptor interaction pathway, sphingolipid metabolism, etc. This study provides novel insights into the functional interactions of Cannabis sativa L. extract on PIPN.


Assuntos
Analgésicos , Cannabis , Neuralgia , Paclitaxel , Extratos Vegetais , Animais , Cannabis/química , Neuralgia/induzido quimicamente , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Ratos , Analgésicos/farmacologia , Analgésicos/química , Paclitaxel/efeitos adversos , Masculino , Metabolômica , Modelos Animais de Doenças , Hiperalgesia/tratamento farmacológico , Hiperalgesia/induzido quimicamente , Hiperalgesia/metabolismo , Canabinoides/farmacologia , Multiômica
4.
Opt Express ; 31(12): 19463-19477, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381361

RESUMO

A lensless camera is an imaging system that replaces the lens with a mask to reduce thickness, weight, and cost compared to a lensed camera. The improvement of image reconstruction is an important topic in lensless imaging. Model-based approach and pure data-driven deep neural network (DNN) are regarded as two mainstream reconstruction schemes. In this paper, the advantages and disadvantages of these two methods are investigated to propose a parallel dual-branch fusion model. The model-based method and the data-driven method serve as two independent input branches, and the fusion model is used to extract features from the two branches and merge them for better reconstruction. Two types of fusion model named Merger-Fusion-Model and Separate-Fusion-Model are designed for different scenarios, where Separate-Fusion-Model is able to adaptively allocate the weights of the two branches by the attention module. Additionally, we introduce a novel network architecture named UNet-FC into the data-driven branch, which enhances reconstruction by making full use of the multiplexing property of lensless optics. The superiority of the dual-branch fusion model is verified by drawing comparison with other state-of-the-art methods on public dataset (+2.95dB peak signal-to-noise (PSNR), +0.036 structural similarity index (SSIM), -0.0172 Learned Perceptual Image Patch Similarity (LPIPS)). Finally, a lensless camera prototype is constructed to further validate the effectiveness of our method in a real lensless imaging system.

5.
Planta Med ; 89(15): 1444-1456, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37709286

RESUMO

The discovery that Na/K-ATPase acts as a signal transducer led us to investigate the structural diversity of cardiotonic steroids and study their ligand effects. By applying Na/K-ATPase activity assay-guided fractionation, we isolated a total of 20 cardiotonic steroids from Streptocaulon juventas, including an undescribed juventasoside B (10: ) and 19 known cardiotonic steroids. Their structures have been elucidated. Using our platform of purified Na/K-ATPase and an LLC-PK1 cell model, we found that 10: , at a concentration that induces less than 10% Na/K-ATPase inhibition, can stimulate the Na/K-ATPase/Src receptor complex and selectively activate downstream pathways, ultimately altering prostate cancer cell growth. By assessing the ligand effect of the isolated cardiotonic steroids, we found that the regulation of cell viability by the isolated cardiotonic steroids was not associated with their inhibitory potencies against Na/K-ATPase activity but reflected their ligand-binding affinity to the Na/K-ATPase receptor. Based on this discovery, we identified a unique active cardiotonic steroid, digitoxigenin (1: ), and verified that it can protect LLC-PK1 cells from hypoxic injury, implicating its potential use in ischemia/reperfusion injury and inducing collagen synthesis in primary human dermal fibroblast cells, and implicating that compound 2: is the molecular basis of the wound healing activity of S. juventas.


Assuntos
Cardenolídeos , Glicosídeos Cardíacos , Masculino , Suínos , Animais , Humanos , Cardenolídeos/farmacologia , Ligantes , Glicosídeos Cardíacos/química , ATPase Trocadora de Sódio-Potássio/metabolismo , Cicatrização , Ouabaína/farmacologia
6.
Biochem Biophys Res Commun ; 619: 84-89, 2022 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-35749940

RESUMO

Fibroblast growth factor 21 (FGF21) is regulated by peroxisome proliferator activated receptor α (PPARα) in the liver. FGF21 regulates lipid metabolism via fibroblast growth factor receptor 1 (FGFR1). FGF21 protect against alcoholic fatty liver (AFL), however, FGF21 does not exert protective effect through liver FGFR1. We have previously shown that PPARα agonist WY-14,643 induces FGF21 and adipose atrophy but fails to protect against chronic ethanol-induced AFL in mice lacking adipose FGFR1. In this study we tested the direct role of the FGF21 in regulation of adipose tissue mass and ethanol induced-hepatic triglyceride (TG) accumulation in normal control (fgfr1fl/fl) mice and in adipose FGFR1 knockout mice (fgfr1adipoQ-cre). First, we tested whether WY-14,643 effects on adipose atrophy and AFL can be recapitulated in binge alcohol model. As in chronic model, adipose tissue mass and serum free fatty acid (FFA) were decreased by WY-14,643 in the fgfr1adipoQ-cre mice but not in the fgfr1fl/fl mice. However, in contrast to the chronic model, binge ethanol-induced AFL was blunted by WY-14,643 to a greater extent in the fgfr1adipoQ-cre mice than in the fgfr1fl/fl mice. Similarly, circulating FGF21 was elevated by binge ethanol to a greater extent in the fgfr1adipoQ-cre mice than in the fgfr1fl/fl mice on top of WY-14,643 treatment. Accordingly, we tested the involvement of the FGF21 in adipose atrophy and AFL. Consistent with FGFR1-dependent effects of WY-14,643 on adipose atrophy and AFL, recombinant mouse FGF21 (rFGF21) injection induced adipose atrophy, blunted AFL and serum TG elevation to a greater extent in the fgfr1adipoQ-cre mice than in the fgfr1fl/fl mice. These results indicated the consistency of adipose FGFR1 dependent effect of WY-14,643 and FGF21 in PPARα-mediated regulation of adipose tissue mass and fat mobilization from adipose tissues to the liver, suggesting that adipose tissues crosstalk with liver through an interaction between liver PPARα-FGF21 and adipose FGFR1 to maintain adipose tissue mass.


Assuntos
Fígado Gorduroso Alcoólico , PPAR alfa , Tecido Adiposo/metabolismo , Animais , Atrofia , Etanol/farmacologia , Fígado Gorduroso Alcoólico/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Knockout , PPAR alfa/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo
7.
Biochem Biophys Res Commun ; 613: 47-52, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35526488

RESUMO

Peroxisome proliferator-activated receptor α (PPARα) regulates fatty acid oxidation (FAO). Usually, very-long chain fatty acids are first activated by acyl-CoA synthetase (ACS) to generate acyl-CoA for oxidation by acyl-CoA oxidase (ACOX) in peroxisomes, and the resultant shorter chain fatty acids will be further oxidized in mitochondria. ACS long-chain family member 4 (ACSL4) preferentially uses arachidonic acid (AA) as substrates to synthesize arachidonoyl-CoA. Arachidonoyl-CoA is usually esterified into phospholipids. When AA is released by phospholipase A2 (PLA2) from phospholipids, it will be used for prostaglandin synthesis by cyclooxygenases (COX). In this study, when PPARα agonist WY-14,643 was mixed in liquid Lieber-DeCarli ethanol or control diets and fed to mice, liver PLA2, COX-2, and ACOX1 were induced but ACSL4 was inhibited, suggesting that AA released by PLA2 from phospholipid will be metabolized to prostaglandin via COX-2 instead of being synthesized into acyl-CoA by ACSL4. However, liver prostaglandin E2 (PGE2), a major component of prostaglandin, was not increased with the induced COX-2 but decreased by WY-14,643. ACOX1 specific inhibitor mixed in the liquid diets restored both the WY-14,643-suppressed liver TG and PGE2, but COX-2 specific inhibitor celecoxib mixed in the liquid diets reversed the WY-14,643-suppressed liver TG but not liver PGE2 contents. These results suggest that induction of PLA2, COX-2 and ACOX1 orchestrates to increase oxidation of AA/PGE2, which constitutes one new mechanism by which PPARα induces peroxisomal FAO and inhibits ethanol-induced liver fat accumulation.


Assuntos
Acil-CoA Oxidase , Ciclo-Oxigenase 2 , Fígado Gorduroso Alcoólico , PPAR alfa , Fosfolipases A2 , Pirimidinas , Acil-CoA Oxidase/metabolismo , Animais , Coenzima A/metabolismo , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Ácidos Graxos/metabolismo , Fígado Gorduroso Alcoólico/tratamento farmacológico , Fígado Gorduroso Alcoólico/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Camundongos , PPAR alfa/agonistas , PPAR alfa/metabolismo , Peroxissomos/efeitos dos fármacos , Peroxissomos/metabolismo , Fosfolipases A2/metabolismo , Fosfolipídeos/metabolismo , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos
8.
Mol Pharmacol ; 99(3): 217-225, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33495275

RESUMO

Recent studies have revealed that Na/K-ATPase (NKA) can transmit signals through ion-pumping-independent activation of pathways relayed by distinct intracellular protein/lipid kinases, and endocytosis challenges the traditional definition that cardiotonic steroids (CTS) are NKA inhibitors. Although additional effects of CTS have long been suspected, revealing its agonist impact through the NKA receptor could be a novel mechanism in understanding the basic biology of NKA. In this study, we tested whether different structural CTS could trigger different sets of NKA/effector interactions, resulting in biased signaling responses without compromising ion-pumping capacity. Using purified NKA, we found that ouabain, digitoxigenin, and somalin cause comparable levels of NKA inhibition. However, although endogenous ouabain stimulates both protein kinases and NKA endocytosis, digitoxigenin and somalin bias to protein kinases and endocytosis, respectively, in LLC-PK1 cells. The positive inotropic effects of CTS are traditionally regarded as NKA inhibitors. However, CTS-induced signaling occurs at concentrations at least one order of magnitude lower than that of inotropy, which eliminates their well known toxic actions on the heart. The current study adds a novel mechanism that CTS could exert its biased signaling properties through the NKA signal transducer. SIGNIFICANCE STATEMENT: Although it is now well accepted that NKA has an ion-pumping-independent signaling function, it is still debated whether direct and conformation-dependent NKA/effector interaction is a key to this function. Therefore, this investigation is significant in advancing our understanding of the basic biology of NKA-mediated signal transduction and gaining molecular insight into the structural elements that are important for cardiotonic steroid's biased action.


Assuntos
Glicosídeos Cardíacos/farmacologia , Digitoxigenina/farmacologia , Glicosídeos/farmacologia , Ouabaína/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Células LLC-PK1 , ATPase Trocadora de Sódio-Potássio/metabolismo , Suínos
9.
Int J Mol Sci ; 22(7)2021 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-33801629

RESUMO

The Na/K-ATPase is the specific receptor for cardiotonic steroids (CTS) such as ouabain and digoxin. At pharmacological concentrations used in the treatment of cardiac conditions, CTS inhibit the ion-pumping function of Na/K-ATPase. At much lower concentrations, in the range of those reported for endogenous CTS in the blood, they stimulate hypertrophic growth of cultured cardiac myocytes through initiation of a Na/K-ATPase-mediated and reactive oxygen species (ROS)-dependent signaling. To examine a possible effect of endogenous concentrations of CTS on cardiac structure and function in vivo, we compared mice expressing the naturally resistant Na/K-ATPase α1 and age-matched mice genetically engineered to express a mutated Na/K-ATPase α1 with high affinity for CTS. In this model, total cardiac Na/K-ATPase activity, α1, α2, and ß1 protein content remained unchanged, and the cardiac Na/K-ATPase dose-response curve to ouabain shifted to the left as expected. In males aged 3-6 months, increased α1 sensitivity to CTS resulted in a significant increase in cardiac carbonylated protein content, suggesting that ROS production was elevated. A moderate but significant increase of about 15% of the heart-weight-to-tibia-length ratio accompanied by an increase in the myocyte cross-sectional area was detected. Echocardiographic analyses did not reveal any change in cardiac function, and there was no fibrosis or re-expression of the fetal gene program. RNA sequencing analysis indicated that pathways related to energy metabolism were upregulated, while those related to extracellular matrix organization were downregulated. Consistent with a functional role of the latter, an angiotensin-II challenge that triggered fibrosis in the α1r/rα2s/s mouse failed to do so in the α1s/sα2s/s. Taken together, these results are indicative of a link between circulating CTS, Na/K-ATPase α1, ROS, and physiological cardiac hypertrophy in mice under baseline laboratory conditions.


Assuntos
Glicosídeos Cardíacos/química , Coração/fisiologia , Miocárdio/enzimologia , ATPase Trocadora de Sódio-Potássio/genética , Angiotensina II/farmacologia , Animais , Cardiomegalia/patologia , Modelos Animais de Doenças , Ecocardiografia , Coração/efeitos dos fármacos , Masculino , Camundongos , Mutação , Ouabaína/farmacologia , Isoformas de Proteínas , RNA-Seq , Espécies Reativas de Oxigênio , Transdução de Sinais/efeitos dos fármacos
10.
Bioorg Chem ; 98: 103150, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31983469

RESUMO

ß-Sitosterols, is a common steroid that can be identified in a variety of plants and their efficacy in promoting wound healing has been demonstrated. Na+/K+-ATPase, more than a pump, its signal transduction function for involvement in cell growth regulation attracts widespread concern. The Na+/K+-ATPase/Src receptor complex can serve as a receptor involved in multiple signaling pathways including promoting wound healing pathways. To finding potent accelerating wound healing small molecular, we choose the high inhibitory activity of Na+/K+-ATPase and non-cardiotoxic natural compound, ß-sitosterol as the substrate. A series of ß-sitosterol derivatives were designed, synthesized and evaluated as potential Na+/K+-ATPase inhibitors. Among them, compounds 31, 47, 49, showed improved inhibitory activity on Na+/K+-ATPase, with IC50 value of 3.0 µM, 3.4 µM, 2.2 µM, which are more potent than ß-sitosterol with IC50 7.6 µM. Especially, compound 49 can induce cell proliferation, migration and soluble collagen production in L929 fibroblasts. Compared to model, compound 49 can accelerate wound healing in SD rats. Further studies indicated that 49 can activate the sarcoma (Src), uptake the protein kinase B (Akt), extracellular signal-regulated kinase (ERK) proteins expression in a concentration dependent manner. Finally, binding mode of compound 49 with Na+/K+-ATPase was studied, which provides insights into the determinants of potency and selectivity. These results proved ß-stitosterol derivative 49 can serve as an effective inhibitor of Na+/K+-ATPase and potential candidate for accelerating wound healing agents.


Assuntos
Inibidores Enzimáticos/farmacologia , Sitosteroides/farmacologia , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Cicatrização/efeitos dos fármacos , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Masculino , Camundongos , Estrutura Molecular , Ratos , Ratos Sprague-Dawley , Sitosteroides/síntese química , Sitosteroides/química , ATPase Trocadora de Sódio-Potássio/metabolismo , Relação Estrutura-Atividade
11.
Molecules ; 25(17)2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32825728

RESUMO

In this study, oxidized chitosan grafted cashmere fibers (OCGCFs) were obtained by crosslinking the oxidized chitosan onto cashmere fibers by amide covalent modification. A novel method was developed for the selective oxidation of the C6 primary hydroxyls into carboxyl groups for chitosan. The effect of oxidization reaction parameters of HNO3/H3PO4-NaNO2 mediated oxidation system on the oxidation degree, structure, and properties of chitosan were investigated. The chemical structure of the oxidized chitosan was characterized by solid-state cross-polarization magic angle spinning carbon-13 Nuclear Magnetic Resonance (CP/MAS 13C-NMR), Fourier transform infrared spectroscopy (FT-IR), and its morphology was investigated by scanning electron microscopy (SEM). Subsequently, the effect of the oxidized chitosan grafting on OCGCF was examined, and the physical properties, moisture regain, and antibacterial activity of OCGCFs were also evaluated. The results showed that oxidation of chitosan mostly occurred at the C6 primary hydroxyl groups. Moreover, an oxidized chitosan with 43.5-56.8% carboxyl content was realized by ranging the oxidation time from 30 to 180 min. The resulting OCGCF had a C-N amido bond, formed as a result of the reaction between the primary amines in the cashmere fibers and the carboxyl groups in the oxidized chitosan through the amide reaction. The OCGCF exhibited good moisture regain and remarkable bacteriostasis against both Staphylococcus aureus and Escherichia coli bacteria with its durability.


Assuntos
Amidas/química , Bactérias/efeitos dos fármacos , Quitosana/química , Quitosana/farmacologia , Têxteis/análise , Lã/química , Animais
12.
J Pharmacol Exp Ther ; 371(3): 663-674, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31582423

RESUMO

At concentrations found in humans after ingestion of one to two cups of green tea, epicatechin-3-gallate (ECG) modulates Na/K-ATPase conformation and activity. Akin to ouabain, an archetypal Na/K-ATPase ligand of the cardiotonic steroid (CTS) family, ECG also activates protein kinase C epsilon type (PKCε) translocation and increases the force of contraction of the rat heart. This study evaluated whether, like ouabain, ECG also modulates Na/K-ATPase/Src receptor function and triggers pre- and postconditioning against ischemia/reperfusion (I/R) injury. In vitro, ECG activated the purified Na/K-ATPase/Src complex. In Langendorff-perfused rat hearts, submicromolar concentrations of ECG administered either before or after ischemia reduced infarct size by more than 40%, decreased lactate dehydrogenase release, and improved the recovery of cardiac function. ECG protection was blocked by PKCε inhibition and attenuated by mitochondrial KATP channel inhibition. In a unique mammalian cell system with depleted Na/K-ATPase α1 expression, ECG-induced PKCε activation persisted but protection against I/R was blunted. Taken together, these results reveal a Na/K-ATPase- and PKCε-dependent mechanism of protection by ECG that is also distinct from the mechanism of action of ouabain. These ECG properties likely contribute to the positive impact of green tea consumption on cardiovaascular health and warrant further investigation into the role of cardiac Na/K-ATPase signaling in the cardioprotective effect of green tea consumption. SIGNIFICANCE STATEMENT: Consumption of green tea, the richest dietary source of ECG, is associated with a reduced risk of cardiac mortality. Antioxidant effects of ECG and other tea polyphenols are well known, but reported for concentrations well above dietary levels. Therefore, the mechanism underlying the cardioprotective effect of green tea remains incompletely understood. This study provides experimental evidence that ECG concentrations commonly detected in humans after consumption of a cup of tea trigger the Na/K-ATPase/Src receptor in a cell-free system, activate a CTS-like signaling pathway, and provide PKCε-dependent protection against ischemia/reperfusion injury in rat hearts. Mechanistic studies in mammalian cells with targeted Na/K-ATPase depletion revealed that although Na/K-ATPase does not mediate ECG-induced PKCε activation, it is required for ECG-induced protection against ischemia/reperfusion injury.


Assuntos
Catequina/análogos & derivados , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Catequina/farmacologia , Células Cultivadas , Masculino , Extratos Vegetais/farmacologia , Canais de Potássio/fisiologia , Proteína Quinase C-épsilon/fisiologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/metabolismo , Suínos , Chá
13.
Bioorg Chem ; 87: 265-275, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30908969

RESUMO

Streblus asper Lour. (Moraceae) is a medicinal plant in Asian countries including India and Thailand, possessing activities of anti-tumor, anti-allergy, anti-parasitic and anti-bacterial. In this paper, characterization, quantitation and similarity evaluation of cardiac glycosides in different parts of S. asper were investigated by HPLC-Q-TOF-MS and chemometric methods. Then, the inhibition of Na+,K+-ATPase activity by the compounds isolated from S. asper was measured. Meanwhile, enzyme kinetics and molecular docking were determined to exhibit the combination modes between cardiac glycosides and Na+,K+-ATPase. As a result, twenty peaks of cardiac glycosides were assigned. Strophanthidin-3-O-α-l-rhamnopyranosyl-(1 → 4)-6-deoxy-ß-d-allopyranoside (1), glucostrebloside (2), strebloside (4) and mansonin (8) with a significant activity of inhibiting Na+,K+-ATPase (IC50 7.55-13.60 µM) were chosen for the determination of enzyme kinetics, exhibiting anticompetitive inhibitory characteristics towards Na+,K+-ATPase. Compound 4 could reasonably bind to the active sites of Na+,K+-ATPase, proved by molecular docking. Furthermore, the contents of the major compounds in four different parts of S. asper were extremely different, analyzed by chemometric methods, similarity analysis and principle compounds analysis. All these findings indicated that the contents of major compounds in different parts of S. asper were extremely different with a significant activity of inhibiting Na+,K+-ATPase, providing a reference for determination of effective part and administered dosage. The combination modes between cardiac glycosides and Na+,K+-ATPase were also revealed by enzyme kinetics and molecular docking, which provided a basis for further study of pharmacological activity.


Assuntos
Glicosídeos Cardíacos/farmacologia , Inibidores Enzimáticos/farmacologia , Moraceae/química , Plantas Medicinais/química , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , Animais , Glicosídeos Cardíacos/química , Glicosídeos Cardíacos/isolamento & purificação , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Conformação Molecular , Simulação de Acoplamento Molecular , ATPase Trocadora de Sódio-Potássio/química , ATPase Trocadora de Sódio-Potássio/metabolismo , Relação Estrutura-Atividade , Suínos
14.
J Cardiovasc Pharmacol ; 71(2): 95-103, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29419572

RESUMO

Ouabain preconditioning (OPC) initiated by low concentrations of the cardiac glycoside (CG) ouabain binding to Na/K-ATPase is relayed by a unique intracellular signaling and protects cardiac myocytes against ischemia/reperfusion injury. To explore more clinically applicable protocols based on CG properties, we tested whether the FDA-approved CG digoxin could trigger cardioprotective effects comparable with those of ouabain using PC, preconditioning and PostC, postconditioning protocols in the Langendorff-perfused mouse heart subjected to global ischemia and reperfusion. Ouabain or digoxin at 10 µmol/L inhibited Na/K-ATPase activity by approximately 30% and activated PKCε translocation by approximately 50%. Digoxin-induced PC (DigPC), initiated by a transient exposure before 40 minutes of ischemia, was as effective as OPC as suggested by the recovery of left ventricular developed pressure, end-diastolic pressure, and cardiac Na/K-ATPase activity after 30 minutes of reperfusion. DigPC also significantly decreased lactate dehydrogenase release and reduced infarct size, comparable with OPC. PostC protocols consisting of a single bolus injection of 100 nmoles of ouabain or digoxin in the coronary tree at the beginning of reperfusion both improved significantly the recovery of left ventricular developed pressure and decreased lactate dehydrogenase release, demonstrating a functional and structural protection comparable with the one provided by OPC. Given the unique signaling triggered by OPC, these results suggest that DigPostC could be considered for patients with risk factors and/or concurrent treatments that may limit effectiveness of ischemic PostC.


Assuntos
Cardiotônicos/administração & dosagem , Digoxina/administração & dosagem , Inibidores Enzimáticos/administração & dosagem , Contração Miocárdica/efeitos dos fármacos , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/efeitos dos fármacos , Ouabaína/administração & dosagem , Função Ventricular Esquerda/efeitos dos fármacos , Animais , Morte Celular/efeitos dos fármacos , Modelos Animais de Doenças , Preparação de Coração Isolado , Masculino , Camundongos Endogâmicos C57BL , Infarto do Miocárdio/enzimologia , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Traumatismo por Reperfusão Miocárdica/enzimologia , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miócitos Cardíacos/enzimologia , Miócitos Cardíacos/patologia , Proteína Quinase C-épsilon/metabolismo , Recuperação de Função Fisiológica , Transdução de Sinais/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores , ATPase Trocadora de Sódio-Potássio/metabolismo , Pressão Ventricular/efeitos dos fármacos
15.
J Asian Nat Prod Res ; 20(4): 352-360, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28640646

RESUMO

A new enzyme-linked immunosorbent assay (ELISA) method for quantitative determination of monoester-type aconitic alkaloids was developed. The antibodies derived from the immunogen of benzoylmesaconine (BM) could be electively affined to benzoylaconitine-type alkaloids with an ester bond (14-benzoyl-), especially to benzoylhypaconine (BH, 140.02% of cross-reactivity). The effective working range of BH was 1 ng/ml to 5 µg/ml; the lower limit of detection and the quantification were 0.35 and 0.97 ng/ml, respectively. The values of CV for intra-day and inter-day assays and recovery ratios were in acceptable ranges. The results of stability experiments were also satisfactory. This validated method was employed for pharmacokinetic study of BH in rats and the bioavailability orally administered was estimated to be 16.3%.


Assuntos
Alcaloides/análise , Ensaio de Imunoadsorção Enzimática/métodos , Aconitina/análogos & derivados , Aconitum/química , Alcaloides/farmacocinética , Animais , Cromatografia Líquida de Alta Pressão/métodos , Estrutura Molecular , Ratos
16.
Am J Physiol Cell Physiol ; 312(3): C222-C232, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-27903584

RESUMO

The Na/K-ATPase α1 polypeptide supports both ion-pumping and signaling functions. The Na/K-ATPase α3 polypeptide differs from α1 in both its primary structure and its tissue distribution. The expression of α3 seems particularly important in neurons, and recent clinical evidence supports a unique role of this isoform in normal brain function. The nature of this specific role of α3 has remained elusive, because the ubiquitous presence of α1 has hindered efforts to characterize α3-specific functions in mammalian cell systems. Using Na/K-ATPase α1 knockdown pig kidney cells (PY-17), we generated the first stable mammalian cell line expressing a ouabain-resistant form of rat Na/K-ATPase α3 in the absence of endogenous pig α1 detectable by Western blotting. In these cells, Na/K-ATPase α3 formed a functional ion-pumping enzyme and rescued the expression of Na/K-ATPase ß1 and caveolin-1 to levels comparable with those observed in PY-17 cells rescued with a rat Na/K-ATPase α1 (AAC-19). The α3-containing enzymes had lower Na+ affinity and lower ouabain-sensitive transport activity than their α1-containing counterparts under basal conditions, but showed a greater capacity to be activated when intracellular Na+ was increased. In contrast to Na/K-ATPase α1, α3 could not regulate Src. Upon exposure to ouabain, Src activation did not occur, yet ERK was activated through Src-independent pathways involving PI3K and PKC. Hence, α3 expression confers signaling and pumping properties that are clearly distinct from that of cells expressing Na/K-ATPase α1.


Assuntos
Ativação do Canal Iônico/fisiologia , Rim/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Sódio/metabolismo , Células-Tronco/enzimologia , Quinases da Família src/metabolismo , Animais , Linhagem Celular , Proliferação de Células/fisiologia , Rim/citologia , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Ratos
17.
J Asian Nat Prod Res ; 16(2): 141-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23919635

RESUMO

A series of flavone glycosides were isolated from Fructus Kochiae for the first time, including two new flavone glycosides. The structures were established by interpretation of their spectroscopic data. Two new flavone glycosides are quercetin 3-O-ß-d-apiofuranosyl-(1 â†’ 2)-ß-d-galactopyranosyl-7-O-ß-d-glucopyranoside (1) and quercetin 3-O-α-l-rhamnopyranosyl-(1 â†’ 6)-ß-d-galactopyranosyl-7-O-ß-d-sophoroside (2). The others are quercetin 7-O-ß-d-glucopyranoside (3), quercetin 3-O-ß-d-apiofuranosyl-(1 â†’ 2)-ß-d-galactopyranoside (4), quercetin 3-O-ß-d-galactopyranosyl-7-O-ß-d-glucopyranoside (5), and quercetin 7-O-ß-d-sophoroside (6).


Assuntos
Bassia scoparia/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Flavonas/isolamento & purificação , Glicosídeos/isolamento & purificação , Quercetina/análogos & derivados , Medicamentos de Ervas Chinesas/química , Flavonas/química , Frutas/química , Glicosídeos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Quercetina/química , Quercetina/isolamento & purificação
18.
ACS Omega ; 9(16): 18032-18045, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38680313

RESUMO

Spherical δ-MnO2 nanoflower materials were synthesized via a facile one-step coprecipitation method through adjusting the molar ratio of KMnO4 to MnSO4. The influence of the molar ratio of the reactants on the crystal structure, morphology, and electrochemical performances was investigated. At a molar ratio of 3.3 for KMnO4 to MnSO4, the spherical δ-MnO2 nanoflowers composed of nanosheets with the highest specific surface area (228.0 m2 g-1) were obtained as electrode materials. In the conventional three-electrode system using 1 M Na2SO4 as an electrolyte, the specific capacitance of the spherical δ-MnO2 nanoflowers reached 172.3 F g-1 at a current density of 1 A g-1. Moreover, even after 5000 cycles at a current density of 5 A g-1, the GCD curves remained essentially unchanged, and the specific capacitance still retained 86.50% of the maximum value. The kinetics of the electrode reaction were preliminarily studied through the linear potential sweep technique to observe diffusion-controlled contribution toward total capacitance. For the spherical δ-MnO2 nanoflower electrode material, diffusion-controlled contribution accounted for 65.1% at low scan rates and still remained significant at high scan rates (100 mV s-1), indicating excellent utilization efficiency of the bulk phase. The as-fabricated asymmetric supercapacitor HFC-7//MnO2-3.3-ASC presented a prominent specific energy of 16.5 Wh kg-1 at the specific power of 450 W kg-1. Even when the specific power reached 9.0 kW kg-1, the energy density still retained 9.5 Wh kg-1.

19.
Fitoterapia ; 177: 106092, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38914272

RESUMO

Hemp (Cannabis sativa L.), an annual dioecious plant, has shown extensive application in the fields of fibers, food, oil, medicine, etc. Currently, most attention has been paid to the therapeutic properties of phytocannabinoids. However, the pharmaceutical research on essential oil from hemp is still lacking. In this study, hemp essential oil (HEO) was extracted from hemp flowers and leaves, and the components were analyzed by GC-MS. Quatitative analysis of three main compounds ß-caryophyllene, ß-caryophyllene oxide, α -humulene were determined by GC-FID. The anti-tumor and anti-neuropathic pain effects of HEO were evaluated. In the paclitaxel induced neuropathic mice model, HEO reduced the serum level of inflammatory cytokines TNF-α to achieve the analgesic effect, which was tested by evaluating mechanical and thermal hyperalgesia. Further investigation with cannabinoid receptor 2 (CB2 R) antagonist AM630 revealed the mechanism of reversing mechanical hyperalgesia may be related to CB2 R. In Lewis lung cancer grafted mice model, the tumor growth was significantly inhibited, the levels of tumor inflammatory cytokines TNF-α and IL-6 were downregulated, immune organ index was modified and immune-related CD4+, CD8+ T lymphocytes level, CD4+/CD8+ ratio were increased when administered with HEO. These results reveal that HEO plays a role not only in tumor chemotherapy induced peripheral neuropathy treatment, but also in anti-tumor treatment which offers key information for new strategies in cancer treatment and provides reference for the medicinal development of hemp.

20.
Sci Rep ; 13(1): 8304, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37221295

RESUMO

Alzheimer's disease (AD) is the most common cause of dementia. A common finding in AD is DNA damage. Double-strand DNA breaks (DSBs) are particularly hazardous to neurons because their post-mitotic state forces neurons to rely on error-prone and potentially mutagenic mechanisms to repair DNA breaks. However, it remains unclear whether DNA damage results from increased DNA damage or failure of DNA repair. Oligomerization of the tumor suppressor protein p53 is an essential part of DSB repair, and p53 phosphorylated on S15 is an indicator of DNA damage. We report that the monomer:dimer ratio of phosphorylated (S15) p53 is increased by 2.86-fold in temporal lobes of AD patients compared to age-matched controls, indicating that p53 oligomerization is compromised in AD. In vitro oxidation of p53 with 100 nM H2O2 produced a similar shift in the monomer:dimer ratio. A COMET test showed a higher level of DNA degradation in AD consistent with double-strand DNA damage or inhibition of repair. Protein carbonylation was also elevated (190% of control), indicating elevated oxidative stress in AD patients. Levels of the DNA repair support protein 14-3-3σ, γ-H2AX, a phosphorylated histone marking double strand DNA breaks, and phosphorylated ataxia telangiectasia mutated (ATM) protein were all increased. cGAS-STING-interferon signaling was impaired in AD and was accompanied by a depletion of STING protein from Golgi and a failure to elevate interferon despite the presence of DSBs. The results suggest that oxidation of p53 by ROS could inhibit the DDR and decrease its ability to orchestrate DSB repair by altering the oligomerization state of p53. The failure of immune-stimulated DNA repair may contribute to cell loss in AD and suggests new therapeutic targets for AD.


Assuntos
Doença de Alzheimer , Humanos , Peróxido de Hidrogênio , Proteína Supressora de Tumor p53 , Reparo do DNA , Quebras de DNA de Cadeia Dupla , Interferons
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