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1.
Nat Hum Behav ; 8(3): 544-561, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38172630

RESUMO

Transformer models such as GPT generate human-like language and are predictive of human brain responses to language. Here, using functional-MRI-measured brain responses to 1,000 diverse sentences, we first show that a GPT-based encoding model can predict the magnitude of the brain response associated with each sentence. We then use the model to identify new sentences that are predicted to drive or suppress responses in the human language network. We show that these model-selected novel sentences indeed strongly drive and suppress the activity of human language areas in new individuals. A systematic analysis of the model-selected sentences reveals that surprisal and well-formedness of linguistic input are key determinants of response strength in the language network. These results establish the ability of neural network models to not only mimic human language but also non-invasively control neural activity in higher-level cortical areas, such as the language network.


Assuntos
Compreensão , Idioma , Humanos , Compreensão/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Linguística/métodos , Mapeamento Encefálico/métodos
2.
Brain Res ; 1824: 148676, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-37956747

RESUMO

The olfactory bulbectomy (OBX) animal model of depression reproduces the behavioral and neurochemical changes observed in depressed patients. We assessed the therapeutic effects of the Jieyu Chufan (JYCF) capsule on OBX rats. JYCF ameliorated the hedonic and anxiety-like behavior of OBX rats and attenuated the cortical and hippocampal damage. JYCF enhanced the expression of neurotrophic factors, such as brain-derived neurotrophic factor (BDNF), fibroblast growth factor 2 (FGF2), and adiponectin (ADPN) in the cortex and hippocampus of OBX rats. JYCF also reduced cortisol levels and restored the levels of excitatory neurotransmitters, such as 5-hydroxytryptamine (5-HT), acetylcholine (ACH), and glutamic acid (Glu), in the brain tissue of OBX rats. Our results suggest that JYCF preserves the synaptic structure by increasing the levels of synaptophysin (SYN) and postsynaptic density protein 95 (PSD95) and alleviates the histological alterations of brain tissue by activating AKT/PKA-CREB-BDNF pathways, and by upregulating ADPN and FGF2 expression in OBX rats. JYCF exerts multiple therapeutic effects on depression, including modulating neurotransmitters, repairing neuronal damage, and maintaining synaptic integrity. These findings support the potential of JYCF as a novel antidepressant agent with therapeutic effects on depression and related neurological disorders.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Depressão , Humanos , Ratos , Animais , Depressão/tratamento farmacológico , Depressão/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Neurotransmissores/metabolismo , Bulbo Olfatório/metabolismo , Modelos Animais de Doenças
3.
J Vis Exp ; (202)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38145382

RESUMO

The treatment of central nervous disorders has consistently posed significant challenges to the medical field. Acupuncture, a non-pharmacological practice rooted in traditional Chinese medicine, entails the insertion of fine needles into precise points on the body and is commonly employed for the management of diverse conditions. Recently, acupuncture has emerged as a promising therapeutic intervention for a range of neurological diseases, including anxiety and respiratory disorders. However, the potential of acupuncture in treating cognitive dysfunction induced by chronic hypoxia has not yet been explored. This paper presents a comprehensive protocol for establishing a mouse model of chronic hypoxia-induced cognitive impairment, administering mild anesthesia, performing acupuncture treatment, and assessing behavioral changes and memory abilities using open field tests and water mazes. The step-by-step protocol provides detailed instructions on accurately locating and positioning acupoints and needles for cognitive improvement. By employing this protocol, researchers can conduct systematic studies to thoroughly evaluate the therapeutic potential of acupuncture for cognitive dysfunction.


Assuntos
Terapia por Acupuntura , Anestesia , Disfunção Cognitiva , Camundongos , Animais , Terapia por Acupuntura/métodos , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/terapia , Medicina Tradicional Chinesa/métodos , Hipóxia/terapia , Modelos Animais de Doenças , Pontos de Acupuntura
4.
bioRxiv ; 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37090673

RESUMO

Transformer models such as GPT generate human-like language and are highly predictive of human brain responses to language. Here, using fMRI-measured brain responses to 1,000 diverse sentences, we first show that a GPT-based encoding model can predict the magnitude of brain response associated with each sentence. Then, we use the model to identify new sentences that are predicted to drive or suppress responses in the human language network. We show that these model-selected novel sentences indeed strongly drive and suppress activity of human language areas in new individuals. A systematic analysis of the model-selected sentences reveals that surprisal and well-formedness of linguistic input are key determinants of response strength in the language network. These results establish the ability of neural network models to not only mimic human language but also noninvasively control neural activity in higher-level cortical areas, like the language network.

5.
Phytomedicine ; 112: 154688, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36738478

RESUMO

BACKGROUND: Sophoridine (SR) has shown the potential to be an antiarrhythmic agent. However, SR's electrophysiological properties and druggability research are relatively inadequate, which limits the development of SR as an antiarrhythmic candidate. PURPOSE: To facilitate the development process of SR as an antiarrhythmic candidate, we performed integrated studies on the electrophysiological properties of SR in vitro and ex vivo to gain more comprehensive insights into the multi-ion channel blocking effects of SR, which provided the foundation for the further drugability studies in antiarrhythmic and safety studies. Firstly, SR's electrophysiological properties and antiarrhythmic potentials were recorded and assessed at the cell and tissue levels by comprehensively integrating the patch clamp with the Electrical and Optical Mapping systems. Subsequently, the antiarrhythmic effects of SR were validated by aconitine and ouabain-induced arrhythmia in vivo. Finally, the safety of SR as an antiarrhythmic candidate compound was evaluated based on the guidelines of the Comprehensive in Vitro Proarrhythmia Assay (CiPA). STUDY DESIGN: The antiarrhythmic effect of SR was evaluated at the in vitro, ex vivo, and in vivo levels. METHODS: Isolated primary cardiomyocytes and stable cell lines were prepared to explore the electrophysiologic properties of being a multiple ion-channel blocker in vitro by whole-cell patch clamp. Using electrical and optical mapping, the negative chronotropic effect of SR was determined in langendorff-perfused rat or guinea-pig hearts.The antiarrhythmic activity of SR was assessed by the ex vivo tachyarrhythmia models induced by left coronary artery ligation (LCAL) and isoproterenol (ISO). Canonical models of aconitine and ouabain-induced arrhythmia were used to verify the antiarrhythmic effects in vivo. Finally, the pro-arrhythmic risk of SR was detected in Human-Induced Pluripotent Stem Cell-Derived Cardiomyocytes (hSCCMs) using a Microelectrode array (MEA). RESULTS: Single-cell patch assay validated the multiple ion-channel blockers of SR in transient outward current potassium currents (Ito), l-type calcium currents (ICa-l), and rapid activation delayed rectifier potassium currents (IKr). SR ex vivo depressed heart rates (HR) and ventricular conduction velocity (CV) and prolonged Q-T intervals in a concentration-dependent manner. Consistent with the changes in HRs, SR extended the active time of hearts and increased the action potential duration measured at 90% repolarization (APD90). SR could also significantly lengthen the onset time and curtail the duration of spontaneous ventricular tachycardia (VT) in the ex vivo arrhythmic model induced by LCAL. Meanwhile, SR could also significantly upregulate the programmed electrical stimulation (PES) frequency after the ISO challenge in forming electrical alternans and re-entrant excitation. Furthermore, SR exerted antiarrhythmic effects in the tachyarrhythmia models induced by aconitine and ouabain in vivo. Notably, the pro-arrhythmic risk of SR was shallow for a moderate inhibition of the human ether-à-go-go-related gene (hERG) channel. Moreover, SR prolonged field potential duration (FPDc) of hSCCMs in a concentration-dependent manner without early after depolarization (EAD) and arrhythmia occurrence. CONCLUSION: Our results indicated that SR manifested as a multiple ion-channel blocker in the electrophysiological properties and exerts antiarrhythmic effects ex vivo and in vivo. Meanwhile, due to the low pro-arrhythmic risk in the hERG inhibition assay and the induction of EAD, SR has great potential as a leading candidate in the treatment of ventricular tachyarrhythmia.


Assuntos
Antiarrítmicos , Matrinas , Ratos , Humanos , Animais , Cobaias , Antiarrítmicos/efeitos adversos , Ouabaína/metabolismo , Ouabaína/farmacologia , Ouabaína/uso terapêutico , Aconitina/farmacologia , Arritmias Cardíacas/induzido quimicamente , Arritmias Cardíacas/tratamento farmacológico , Canais Iônicos/metabolismo , Canais Iônicos/farmacologia , Miócitos Cardíacos , Isoproterenol , Potássio/metabolismo , Potássio/farmacologia , Potássio/uso terapêutico , Potenciais de Ação/fisiologia
6.
Int J Oncol ; 62(3)2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36825592

RESUMO

Cardiac glycosides (CGs) are candidate anticancer agents that function by increasing [Ca2+]i to induce apoptotic cell death in several types of cancer cells. However, new findings have shown that the anti­cancer effects of CGs involve complex cell­signal transduction mechanisms. Hence, exploring the potential mechanisms of action of CGs may provide insight into their anti­cancer effects and thus aid in the selection of the appropriate CG. Periplocymarin (PPM), which is a cardiac glycoside, is an active ingredient extracted from Cortex periplocae. The role of PPM was evaluated in HepG2 cells and xenografted nude mice. Cell proliferation, real­time ATP rate assays, western blotting, cell apoptosis assays, short interfering RNA transfection, the patch clamp technique, electron microscopy, JC­1 staining, immunofluorescence staining and autophagic flux assays were performed to evaluate the function and regulatory mechanisms of PPM in vitro. The in vivo activity of the PPM was assessed using a mouse xenograft model. The present study demonstrated that PPM synchronously activated lethal apoptosis and protective autophagy in liver cancer, and the initiation of autophagy counteracted the inherent pro­apoptotic capacity and impaired the anti­cancer effects. Specifically, PPM exerted a pro­-apoptotic effect in HepG2 cells and activated macroautophagy by initiation of the AMPK/ULK1 and mTOR signaling pathways. Activation of macroautophagy counteracted the pro­apoptotic effects of PPM, but when it was combined with an autophagy inhibitor, the anti­cancer effects of PPM in mice bearing HepG2 xenografts were observed. Collectively, these results indicated that a self­limiting effect impaired the pro­apoptotic effects of PPM in liver cancer, but when combined with an autophagy inhibitor, it may serve as a novel therapeutic option for the management of liver cancer.


Assuntos
Glicosídeos Cardíacos , Neoplasias Hepáticas , Animais , Camundongos , Humanos , Camundongos Nus , Proteínas Quinases Ativadas por AMP/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Glicosídeos Cardíacos/farmacologia , Autofagia , Apoptose , Linhagem Celular Tumoral , Proliferação de Células
7.
Front Plant Sci ; 14: 1308085, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38259919

RESUMO

Background/Aims: Phaeodactylum tricornutum, a model organism of diatoms, plays a crucial role in Earth's primary productivity. Investigating its cellular response to grazing pressure is highly significant for the marine ecological environment. Furthermore, the integration of multi-omics approaches has enhanced the understanding of its response mechanism. Methods: To assess the molecular and cellular responses of P.tricornutum to grazer presence, we conducted transcriptomic, proteomic, and metabolomic analyses, combined with phenotypic data from previous studies. Sequencing data were obtained by Illumina RNA sequencing, TMT Labeled Quantitative Proteomics and Non-targeted Metabolomics, and WGCNA analysis and statistical analysis were performed. Results: Among the differentially expressed genes, we observed complex expression patterns of the core genes involved in the phenotypic changes of P.tricornutum under grazing pressure across different strains and multi-omics datasets. These core genes primarily regulate the levels of various proteins and fatty acids, as well as the cellular response to diverse signals. Conclusion: Our research reveals the association of multi-omics in four strains responses to grazing effects in P.tricornutum. Grazing pressure significantly impacted cell growth, fatty acid composition, stress response, and the core genes involved in phenotype transformation.

8.
Oxid Med Cell Longev ; 2022: 7013299, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401933

RESUMO

Objective: L-3-n-Butylphthalide (NBP) is used to treat moderate and severe acute ischemia stroke. A previous screening study indicates that XY03-EA, a novel derivative of NBP, is more potent than NBP in the oxyradical scavenging capacity. In this study, in vivo and in vitro ischemia/reperfusion (I/R) models were used to test whether the XY03-EA offered therapeutic benefits in the ischemic stroke and explore the underlying mechanism of action. Methods: For this purpose, behavioral scores, cerebral infarct volume, cerebral blood flow, oxidative stress levels, inflammatory factor expression, energy metabolism levels, and autophagy activation were estimated in the rat middle cerebral artery occlusion and reperfusion (MCAO/R) model. The nonhuman primate MCAO/R model was conducted to validate the therapeutic effect of XY03-EA applied for 3 weeks. The neurological deficit score (NDS) progression rate and the infarct volume were continuously recorded on days 3, 7, 14, and 21. The PC-12 cell OGD/R model was used to assess the cell survival rate, reactive oxygen species (ROS) levels, the expression of autophagy execution molecules, and the activation of autophagy-related signaling pathways. Results: XY03-EA decreased the cerebral injuries and NDS by increasing cerebral blood flow, improving brain energy metabolism, accelerating ROS clearance, suppressing inflammatory responses, and inhibiting autophagy in the MCAO/R model rats. In the nonhuman primate MCAO/R model, the treatment of XY03-EA for 3 weeks could significantly inhibit the NDS progression rate and indicate a positive trend to reduce the infarct volume in a dose-dependent way. Mechanistically, XY03-EA inhibited ROS-dependent autophagy activation and thereby protected the PC-12 cells from the autophagic cell death induced by OGD/R. Conclusions: In this study, we found that XY03-EA alleviated the cerebral I/R injuries in rats and nonhuman primates. Our results demonstrated that XY03-EA exerted neuroprotective effects against the ROS-mediated autophagic neurocyte death and had great potential for the treatment of ischemic stroke.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Traumatismo por Reperfusão , Animais , Autofagia , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/prevenção & controle , Infarto da Artéria Cerebral Média , Neuroproteção , Ratos , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-35321503

RESUMO

Background: Scalp acupuncture is a contemporary acupuncture method based on the fundamental theories of traditional acupuncture, which has been widely used in patients with stroke in China. However, the effectiveness is controversial due to lack of solid experimental evidence. Methods: In this study, a rat model of cerebral ischemia-reperfusion injury (CIRI) was established by the middle cerebral artery occlusion/recirculation. The efficacy of scalp acupuncture against CIRI was evaluated by the mNSS scores, TTC staining for brain slices, and laser Doppler perfusion imaging. Immunohistochemical staining for angiogenetic factors indicated the vascularization after CIRI, including VEGF, Ang2, and bFGF. Activation of the Wnt/ß-catenin signaling pathway and p-GSK3ß (ser9)/VEGF pathway in the injured brain tissues was assessed by western blotting and qRT-PCR. Results: On the 7, 14, and 21 days after CIRI, scalp acupuncture could reduce the mNSS scores, decrease the cerebral infarction area, and accelerate the recirculation of ischemic brain tissues. VEGF, FLK1, bFGF, and Ang2 were upregulated on both the mRNA and protein levels in the ischemic brain tissues of the AC group, suggesting that the recirculation might result from angiogenesis, which was also confirmed with the IHC staining in the angiogenetic markers of VEGF, Ang2, and bFGF. Moreover, Wnt3a, ß-catenin, and cyclin D1 were also upregulated on both the mRNA and protein levels in the ischemic brain tissues of the AC group on day 7, 14, and 21, indicating that the Wnt/ß-catenin signaling pathway was activated after the treatment of scalp acupuncture. In contrast, dikkoppf-1 (DKK1) pretreatment, a specific inhibitor for the Wnt/ß-catenin signaling pathway, inactivated the Wnt3a/ß-catenin signaling pathway and exacerbated the infarct size induced by the cerebral IR injury on day 7. Conclusion: Together, our findings demonstrated a mechanism whereby scalp acupuncture led to the activation of Wnt/ß-catenin signaling pathway, promoting angiogenetic factor expression and restoring blood perfusion in the ischemic zone.

10.
Pharm Biol ; 60(1): 274-281, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35138995

RESUMO

CONTEXT: Jinlida (JLD) as a traditional Chinese medicine formula has been used to treat type 2 diabetes mellitus (T2DM) and studies have shown its anti-obesity effect. OBJECTIVE: To investigate the therapeutic effects of JLD in a mouse model of non-alcoholic fatty liver (NAFL). MATERIALS AND METHODS: C57BL/6J mice were divided into three groups and fed a low-diet diet (LFD), high-fat diet (HFD), or HFD + JLD (3.8 g/kg) for 16 weeks, respectively. The free fatty acids-induced lipotoxicity in HepG2 cells were used to evaluate the anti-pyroptotic effects of JLD. The pharmacological effects of JLD on NAFL were investigated by pathological examination, intraperitoneal glucose and insulin tolerance tests, western blotting, and quantitative real-time PCR. RESULTS: In vivo studies showed that JLD ameliorated HFD-induced liver injury, significantly decreased body weight and enhanced insulin sensitivity and improved glucose tolerance. Furthermore, JLD suppressed both the mRNA expression of caspase-1 (1.58 vs. 2.90), IL-1ß (0.93 vs. 3.44) and IL-18 (1.34 vs. 1.60) and protein expression of NLRP3 (2.04 vs. 5.71), pro-caspase-1 (2.68 vs. 4.92) and IL-1ß (1.61 vs. 2.60). In vitro, JLD inhibited the formation of lipid droplets induced by 2 mM FFA (IC50 = 2.727 mM), reduced the protein expression of NLRP3 (0.74 vs. 2.27), caspase-1 (0.57 vs. 2.68), p20 (1.67 vs. 3.33), and IL-1ß (1.44 vs. 2.41), and lowered the ratio of p-IKB-α/IKB-α (0.47 vs. 2.19). CONCLUSION: JLD has a protective effect against NAFLD, which may be related to its anti-pyroptosis, suggesting that JLD has the potential as a novel agent in the treatment of NAFLD.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Hepatócitos/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Piroptose/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Dieta Hiperlipídica , Glucose/metabolismo , Células Hep G2 , Hepatócitos/patologia , Humanos , Resistência à Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL
11.
Chin Med ; 16(1): 104, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34663385

RESUMO

BACKGROUND: Lianhuaqingke (LHQK) has been approved for the treatment of acute tracheobronchitis and exerts a broad-spectrum antiviral effect in our previous study. METHODS: Acute pneumonia caused by HCoV-229E was modeled in BALB/c mice. The anti-viral effect of LHQK was assessed by measuring the lung index and virus titer of lung tissues. The expression levels of pro-inflammatory cytokines in lung tissues and peripheral blood were measured by ELISA. The morphological changes of lung tissues were observed by H&E staining. The subsets of Th cells were assayed by the flow cytometry, including Th0, Th1, Th2, Treg, and Th17. The expression level of MUC5AC in 16HBE cells treated with TNFα was measured by ELISA. Immunofluorescence staining for ß-IV tubulin was used to identify the airway epithelial ciliary in the condition-cultured RTE cells treated with TNFα. The direct antiviral effect of LHQK was assessed in vitro in Vero E6 infected by SARS-CoV-2, validated in vivo in the COVID-19 model of hACE2 transgenic mouse by detecting the lung index, the SARS-CoV-2 virus load, and the morphological changes of lung tissues. RESULTS: LHQK reduced the weight loss and the lung index by inhibiting the HCoV-229E replication and reducing the expression of pro-inflammatory cytokines in lung tissues. An assay for the Th cell subsets in peripheral blood revealed that LHQK could reduce the ratio of Th1/Th2 and increase the Treg/Th17 ratio in a dose-dependent way, which indicated that LHQK could coordinate the Th-mediated immune responses against the virus. In in vitro injury by TNFα, LHQK inhibited MUC5AC expression in 16HBE cells and increased the number of ß-IV tubulin positive staining cells in the condition-cultured RTE cells. In the SARS-CoV-2-infected mice, LHQK could reduce weight loss, inhibit viral replication, and alleviate lung tissue damage. CONCLUSIONS: Our results demonstrate that LHQK exerts therapeutic effects on pneumonia caused by HCoVs (HCoV-229E and SARS-CoV-2) in mice, and that the anti-HCoV effects might depend on its immunomodulatory capacities. All these results suggest that LHQK serves as a potential adjuvant for anti-HCoV therapies.

12.
Artigo em Inglês | MEDLINE | ID: mdl-34367308

RESUMO

OBJECTIVE: The aim of this study was to determine whether Si-Miao-Yong-An decoction (SMYAD) could protect cardiomyocytes from ischemia/reperfusion (I/R) injury and its underlying mechanisms. METHODS: C57BL/6 mice were used to establish a model of myocardial infarction by I/R injury and treated by SMYAD for 4 weeks. Then, the cardiac functions of mice were evaluated by cardiac magnetic resonance (CMR). Histopathological analysis for the heart remodeling was detected by H&E and Masson staining. The protein expression of collagen I, MMP9, and TNFα was detected by western blot in the heart tissues. H9C2 cells were used to establish the hypoxia/reoxygenation (H/R) model and SMYAD intervention. MTT assays detected the cell viability of myocardial cells. The expression level of IL-1ß was evaluated by ELISA. The expression levels of LC3B-II/LC3B-I, p-mTOR, mTOR, NLRP3, procaspase 1, and cleaved-caspase 1 in H9C2 cells were evaluated by Western blot. RESULTS: SMYAD improved cardiac functions such as ventricular volume and ejection fraction of the rats with ischemia/reperfusion injury. Morphological assay indicated that SMYAD reduced the scar size and inhibited fibrosis formation. It was found that SMYAD could regulate collagen I, MMP9, and TNFα protein expression levels in the heart tissues. SMYAD improved the survival rate of H9C2 cardiomyocytes in the H/R injury model. SMYAD elevated the rate of LC3B-II/LC3B-I protein expression, decreased the rate of p-mTOR/mTOR protein expression, and reduced expressions of caspase 1, NLRP3, and IL-1ß in H/R cardiomyocytes. CONCLUSION: SMYAD exerted protective effects on ischemia/reperfusion injury in myocardial cells by activating autophagy and inhibiting pyroptosis. This might be the reason why SMYAD protected myocardial tissue and improved cardiac function in mice with ischemia/reperfusion.

13.
Biomed Pharmacother ; 139: 111581, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33895523

RESUMO

Resibufogenin (RBG) is a chemical ingredient of Chan Su. In our research, we found RBG affected cardiac rhythm in a negative chronotropic way in vivo. The cardiac Mapping system ex vivo and the patch clamp in vitro were used to explore how RBG influenced the cardiac electrophysiological properties. The negative chronotropic action of RBG at 100 µM might be attribute to prolongation in the atrioventricular conduction time and reduction in the ventricular conduction velocity. Using whole-cell patch clamp in ventricular myocytes of adult rats, we found that RBG prolonged the action potential duration (APD) in APD20, APD50, and APD90 at 100 µM and inhibited calcium currents (ICa), total outward potassium currents (IK), and transient outward potassium current (Ito) in a concentration-dependent manner, but not on the inward rectifying potassium current (IK1). Notably, RBG had a potent proarrhythmic action ex vivo in the isolated perfused guinea pig hearts at 10 µM, but not in rats. To avoid the potential cardiotoxicity derived from the distributional differences of ion channels among species, the effect of RGB on IKr in hERG-HEK293 cells was detected. The IC50 of RGB on IKr was more than 100 µM. In summary, all these results indicated that the negative chronotropic action of RBG relied on the blocking activities on multiple ion channels, and the species-difference of proarrhythmic effects might result from lack of the Ito on the myocardial membrane of guinea pigs. Anyhow, the cardiotoxicity observed in guinea pigs required further detailed studies to mitigate the potential risks in the clinical application of Chan Su.


Assuntos
Bufanolídeos/farmacologia , Cardiotônicos/farmacologia , Sistema de Condução Cardíaco/efeitos dos fármacos , Coração/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Animais , Arritmias Cardíacas/induzido quimicamente , Canais de Cálcio/efeitos dos fármacos , Eletrocardiografia/efeitos dos fármacos , Cobaias , Células HEK293 , Frequência Cardíaca/efeitos dos fármacos , Humanos , Miócitos Cardíacos/efeitos dos fármacos , Técnicas de Patch-Clamp , Canais de Potássio/efeitos dos fármacos , Ratos , Especificidade da Espécie
14.
Artigo em Inglês | MEDLINE | ID: mdl-32963571

RESUMO

OBJECTIVE: This study aimed to investigate the mechanistic action and therapeutic effects of Bufei decoction on idiopathic pulmonary fibrosis (IPF) after inhalation of bleomycin. METHODS: Pulmonary fibrosis model in mice was prepared by atomization inhalation of bleomycin. Then, the mice were randomly divided into five groups (control group, model group, positive group, and treatment group) and administrated the drugs for 4 weeks. H&E and Masson's staining of lung tissues were used to observe the morphological changes and deposition of fibers, and the degree of fibrosis was evaluated by hydroxyproline content. The expression and activation of NF-κB were determined by western blotting and immunohistochemistry. The infiltration of macrophages was detected by immunostaining of CD45 and F4/80 in lung tissues. RESULTS: In mouse IPF, Bufei decoction alleviated the pathological changes and the deposition of fibrosis by decreasing the content of hydroxyproline of lung tissues. The antipulmonary fibrosis might rely on the effects of preventing the infiltration of inflammatory cells and inhibiting the expression and activation of NF-κB in lung tissue. CONCLUSION: Bufei decoction improved the process of pulmonary fibrosis by regulating the activation and expression of the NF-κB signal transduction pathway, which provided a therapeutic option for IPF patients.

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