Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 27
Filter
1.
Eur J Pharm Sci ; 199: 106805, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38763450

ABSTRACT

Drug resistance to irreversible epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) is a primary factor affecting their therapeutic efficacy in human non-small cell lung cancer (NSCLC). NSCLC cells can undergo epithelial-mesenchymal transition (EMT) induced by many factors in the tumour microenvironment (TME), which plays a crucial role in tumour drug resistance. In this study, a multicellular lung-on-a-chip that can realise the cell co-culture of the human non-small cell lung cancer cell line HCC827, human foetal lung fibroblasts (HFL-1), and human umbilical vein endothelial cells (HUVECs) is prepared. The TME was simulated on the chip combined with perfusion and other factors, and the drug evaluation of osimertinib was performed to explore the drug resistance mechanism of EGFR-TKIs. In the early stages, a two-dimensional static cell co-culture was achieved by microchip, and the results showed that HFL-1 cells could be transformed into cancer-associated fibroblasts (CAFs), and HCC827 cells could undergo EMT, both of which were mediated by Interleukin-6 (IL-6). Vimentin (VIM) and Alpha Skeletal Muscle Actin (a-SMA) expression of HFL-1 was upregulated, whereas E-cadherin (E-cad) expression of HCC827 was down-regulated. Further, N-cadherin (N-cad) expression of HCC827 was upregulated. In both the static cell co-culture and multicellular lung-on-a-chip, HCC827 cells with CAFs co-culture or IL-6 treatment developed resistance to osimertinib. Further use of the IL-6 antibody inhibitor tocilizumab could reverse EGFR-TKI resistance to a certain extent. Combination therapy with tocilizumab and EGFR-TKIs may provide a novel therapeutic strategy for overcoming EGFR-TKI resistance caused by EMT in NSCLC. Furthermore, the lung-on-a-chip can simulate complex TME and can be used for evaluating tumour resistance and exploring mechanisms, with the potential to become an important tool for personalised diagnosis, treatment, and biomedical research.


Subject(s)
Acrylamides , Aniline Compounds , Coculture Techniques , Drug Resistance, Neoplasm , Epithelial-Mesenchymal Transition , ErbB Receptors , Human Umbilical Vein Endothelial Cells , Lab-On-A-Chip Devices , Lung Neoplasms , Protein Kinase Inhibitors , Humans , ErbB Receptors/metabolism , ErbB Receptors/antagonists & inhibitors , Lung Neoplasms/drug therapy , Lung Neoplasms/metabolism , Drug Resistance, Neoplasm/drug effects , Aniline Compounds/pharmacology , Acrylamides/pharmacology , Acrylamides/therapeutic use , Protein Kinase Inhibitors/pharmacology , Epithelial-Mesenchymal Transition/drug effects , Cell Line, Tumor , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/metabolism , Antineoplastic Agents/pharmacology , Tumor Microenvironment/drug effects , Interleukin-6/metabolism , Cancer-Associated Fibroblasts/drug effects , Cancer-Associated Fibroblasts/metabolism , Lung/drug effects , Lung/metabolism , Indoles , Pyrimidines
2.
Exp Ther Med ; 27(2): 79, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38264431

ABSTRACT

Dystrophic epidermolysis bullosa (DEB) is a rare disease and the associated esophageal stricture is frequently complicated by the lack of clinical experience. The present study reported a very rare case of DEB in a 37-year-old male, who was admitted to Shenzhen Hospital (Shenzhen, China) due to an esophageal stricture. The patient received esophageal dilation under digital subtraction angiography. In this patient, dilation therapy was effective and safe. The patient underwent skin biopsies, and histological examination of the resected tissue specimens confirmed DEB diagnosis. The patient was followed up in the Department of Thoracic Surgery, Shenzhen Hospital, for 2 years without any recurrence of esophageal stricture. This is the first case report of dilation therapy in a very rare case of DEB with a satisfactory outcome, but the long-term efficacy needs further observation. In addition, the latest relevant literature was reviewed and it was found that this treatment is uncommonly reported, as is the condition.

3.
Front Oncol ; 13: 1198746, 2023.
Article in English | MEDLINE | ID: mdl-37427142

ABSTRACT

Background: Lung adenocarcinoma (LUAD), the most common histotype of lung cancer, may have variable prognosis due to molecular variations. The research strived to establish a prognostic model based on malignancy-related risk score (MRRS) in LUAD. Methods: We applied the single-cell RNA sequencing (scRNA-seq) data from Tumor Immune Single Cell Hub database to recognize malignancy-related geneset. Meanwhile, we extracted RNA-seq data from The Cancer Genome Atlas database. The GSE68465 and GSE72094 datasets from the Gene Expression Omnibus database were downloaded to validate the prognostic signature. Random survival forest analysis screened MRRS with prognostic significance. Multivariate Cox analysis was leveraged to establish the MRRS. Furthermore, the biological functions, gene mutations, and immune landscape were investigated to uncover the underlying mechanisms of the malignancy-related signature. In addition, we used qRT-PCR to explore the expression profile of MRRS-constructed genes in LUAD cells. Results: The scRNA-seq analysis revealed the markers genes of malignant celltype. The MRRS composed of 7 malignancy-related genes was constructed for each patient, which was shown to be an independent prognostic factor. The results of the GSE68465 and GSE72094 datasets validated MRRS's prognostic value. Further analysis demonstrated that MRRS was involved in oncogenic pathways, genetic mutations, and immune functions. Moreover, the results of qRT-PCR were consistent with bioinformatics analysis. Conclusion: Our research recognized a novel malignancy-related signature for predicting the prognosis of LUAD patients and highlighted a promising prognostic and treatment marker for LUAD patients.

4.
Cell Rep ; 42(5): 112480, 2023 05 30.
Article in English | MEDLINE | ID: mdl-37163375

ABSTRACT

The cerebellum is essential for motor control and cognitive functioning, engaging in bidirectional communication with the cerebral cortex. The common marmoset, a small non-human primate, offers unique advantages for studying cerebello-cerebral circuits. However, the marmoset cerebellum is not well described in published resources. In this study, we present a comprehensive atlas of the marmoset cerebellum comprising (1) fine-detailed anatomical atlases and surface-analysis tools of the cerebellar cortex based on ultra-high-resolution ex vivo MRI, (2) functional connectivity and gradient patterns of the cerebellar cortex revealed by awake resting-state fMRI, and (3) structural-connectivity mapping of cerebellar nuclei using high-resolution diffusion MRI tractography. The atlas elucidates the anatomical details of the marmoset cerebellum, reveals distinct gradient patterns of intra-cerebellar and cerebello-cerebral functional connectivity, and maps the topological relationship of cerebellar nuclei in cerebello-cerebral circuits. As version 5 of the Marmoset Brain Mapping project, this atlas is publicly available at https://marmosetbrainmapping.org/MBMv5.html.


Subject(s)
Callithrix , Cerebellum , Animals , Magnetic Resonance Imaging , Brain Mapping , Cerebellar Cortex/diagnostic imaging
5.
Clin Transl Gastroenterol ; 14(1): e00557, 2023 01 01.
Article in English | MEDLINE | ID: mdl-36520782

ABSTRACT

INTRODUCTION: Interval colorectal cancer identified before the next surveillance colonoscopy was more likely to be located in the proximal colon. This study aimed to determine whether a second examination of the proximal colon could increase the adenoma detection rate (ADR). METHODS: Patients undergoing colonoscopy for any indications were recruited for the study. After the colonoscopy was completed with the first standard forward view examination of the proximal colon, patients were randomized to either the intervention group, in which the proximal colon was once again inspected, or the control group, in which the proximal colon was inspected once. The primary outcome was the proximal colon ADR. RESULTS: A total of 840 patients were enrolled for intention-to-treat analysis (intervention group, n = 420; control group, n = 420). The proximal colon ADR in the intervention group was significantly higher than that in the control group (35.7% vs 25.2%, P = 0.001). The whole-colon ADR was also higher in the intervention group than in the control group (44.0% vs 34.0%, P = 0.003). The higher ADR in the intervention group was also confirmed by the per-protocol analysis. Older age, adenoma detected on the first proximal colon examination, and longer total proximal colon withdrawal time were independent factors for detecting ≥1 adenoma on the second withdrawal from the proximal colon. DISCUSSION: The second examination of the proximal colon significantly increased the proximal colon ADR and whole-colon ADR in patients undergoing colonoscopy for any indication.


Subject(s)
Adenoma , Colonic Neoplasms , Humans , Prospective Studies , Colonic Neoplasms/diagnosis , Colonoscopy/methods , Adenoma/diagnosis
6.
Article in English | MEDLINE | ID: mdl-36261108

ABSTRACT

The lead (Pb) contamination is considered a lethal threat to birds. However, Pb-induced hepatotoxicology especially its impacts on metabolic processes in the liver of birds is not yet fully understood. Therefore, we tried to determine the toxicological effects of Pb exposure on hepatic carbohydrate and lipid metabolism via Phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway by using an animal model- Japanese quail (Coturnix japonica). One-week old female Japanese quails were randomly allocated into four groups and fed with 0, 50 ppm, 500 ppm and 1000 ppm Pb drinking water respectively for 49 days. The results showed that Pb accumulated in the liver as a dose-dependent manner. Exposure to high dose of Pb (500 and 1000 ppm Pb) led to severe histopathological damages characterized by irregularity and dilation of liver sinusoids, hepatic lipid vacuolization and hepatocellular cytoplasm hyalinization. Meanwhile, Pb exposure caused glycogen increase and lipid droplets decrease in the liver. Pb exposure was also attributable to a decreased triglyceride level in the plasma. In addition, the transcriptional levels of PI3K and Akt in the liver were downregulated by Pb exposure. Subsequently, the mRNA expressions of genes related with glycometabolism in the liver were remarkably altered and the mRNA levels of genes involved in fat synthesis and oxidation in the liver were also markedly changed. it seems that Pb could lead to liver metabolic disorder through structural damages and PI3K/Akt signaling pathway disruption.


Subject(s)
Coturnix , Lipid Metabolism , Animals , Female , Coturnix/metabolism , Lead/toxicity , Liver/metabolism , Phosphatidylinositol 3-Kinase/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , RNA, Messenger/metabolism , Signal Transduction
7.
Innovation (Camb) ; 3(6): 100329, 2022 Nov 08.
Article in English | MEDLINE | ID: mdl-36275864

ABSTRACT

Pathogenic mitochondrial DNA (mtDNA) mutations can cause a variety of human diseases. The recent development of genome-editing technologies to manipulate mtDNA, such as mitochondria-targeted DNA nucleases and base editors, offer a promising way for curing mitochondrial diseases caused by mtDNA mutations. The CRISPR-Cas9 system is a widely used tool for genome editing; however, its application in mtDNA editing is still under debate. In this study, we developed a mito-Cas9 system by adding the mitochondria-targeted sequences and 3' untranslated region of nuclear-encoded mitochondrial genes upstream and downstream of the Cas9 gene, respectively. We confirmed that the mito-Cas9 system was transported into mitochondria and enabled knockin of exogenous single-stranded DNA oligonucleotides (ssODNs) into mtDNA based on proteinase and DNase protection assays. Successful knockin of exogenous ssODNs into mtDNA was further validated using polymerase chain reaction-free third-generation sequencing technology. We also demonstrated that RS-1, an agonist of RAD51, significantly increased knockin efficiency of the mito-Cas9 system. Collectively, we provide direct evidence that mtDNA can be edited using the CRISPR-Cas9 system. The mito-Cas9 system could be optimized as a promising approach for the treatment of mitochondrial diseases caused by pathogenic mtDNA mutations, especially those with homoplasmic mtDNA mutations.

8.
Plant Sci ; 325: 111462, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36126879

ABSTRACT

Laccase (LAC) is a blue multicopper oxidase that contains four copper ions, which is involved in lignin polymerization and flavonoid biosynthesis in plants. Although dozens of LAC genes have been identified in Salvia miltiorrhiza Bunge (a model medicinal plant), most have not been functionally characterized. Here, we explored the expression patterns and the functionality of SmLAC25 in S. miltiorrhiza. SmLAC25 has a higher expression level in roots and responds to methyl jasmonate, auxin, abscisic acid, and gibberellin stimuli. The SmLAC25 protein is localized in the cytoplasm and chloroplasts. Recombinant SmLAC25 protein could oxidize coniferyl alcohol and sinapyl alcohol, two monomers of G-lignin and S-lignin. To investigate its function, we generated SmLAC25-overexpressed S. miltiorrhiza plantlets and hairy roots. The lignin content increased significantly in all SmLAC25-overexpressed plantlets and hairy roots, compared with the controls. However, the concentrations of rosmarinic acid and salvianolic acid B decreased significantly in all the SmLAC25-overexpressed lines. Further studies revealed that the transcription levels of some key enzyme genes in the lignin synthesis pathway (e.g., SmCCR and SmCOMT) were significantly improved in the SmLAC25-overexpressed lines, while the expression levels of multiple enzyme genes in the salvianolic acid biosynthesis pathway were inhibited. We speculated that the overexpression of SmLAC25 promoted the metabolic flux of lignin synthesis, which resulted in a decreased metabolic flux to the salvianolic acid biosynthesis pathway.


Subject(s)
Salvia miltiorrhiza , Salvia miltiorrhiza/genetics , Salvia miltiorrhiza/metabolism , Lignin/metabolism , Alkenes/metabolism , Polyphenols/metabolism , Plant Roots/genetics , Plant Roots/metabolism , Gene Expression Regulation, Plant
9.
Sci Rep ; 12(1): 1075, 2022 01 20.
Article in English | MEDLINE | ID: mdl-35058480

ABSTRACT

Inflammatory diseases including COVID-19 are associated with a cytokine storm characterized by high interleukin-6 (IL-6) titers. In particular, while recent studies examined COVID-19 associated arrhythmic risks from cardiac injury and/or from pharmacotherapy such as the combination of azithromycin (AZM) and hydroxychloroquine (HCQ), the role of IL-6 per se in increasing the arrhythmic risk remains poorly understood. The objective is to elucidate the electrophysiological basis of inflammation-associated arrhythmic risk in the presence of AZM and HCQ. IL-6, AZM and HCQ were concomitantly administered to guinea pigs in-vivo and in-vitro. Electrocardiograms, action potentials and ion-currents were analyzed. IL-6 alone or the combination AZM + HCQ induced mild to moderate reduction in heart rate, PR-interval and corrected QT (QTc) in-vivo and in-vitro. Notably, IL-6 alone was more potent than the combination of the two drugs in reducing heart rate, increasing PR-interval and QTc. In addition, the in-vivo or in-vitro combination of IL-6 + AZM + HCQ caused severe bradycardia, conduction abnormalities, QTc prolongation and asystole. These electrocardiographic abnormalities were attenuated in-vivo by tocilizumab (TCZ), a monoclonal antibody against IL-6 receptor, and are due in part to the prolongation of action potential duration and selective inhibition of Na+, Ca2+ and K+ currents. Inflammation confers greater risk for arrhythmia than the drug combination therapy. As such, in the setting of elevated IL-6 during inflammation caution must be taken when co-administering drugs known to predispose to fatal arrhythmias and TCZ could be an important player as a novel anti-arrhythmic agent. Thus, identifying inflammation as a critical culprit is essential for proper management.


Subject(s)
Arrhythmias, Cardiac , Azithromycin/pharmacology , COVID-19 Drug Treatment , COVID-19 , Hydroxychloroquine/pharmacology , Interleukin-6/metabolism , SARS-CoV-2/metabolism , Animals , Antibodies, Monoclonal, Humanized/pharmacology , Arrhythmias, Cardiac/etiology , Arrhythmias, Cardiac/metabolism , Arrhythmias, Cardiac/physiopathology , Arrhythmias, Cardiac/prevention & control , COVID-19/complications , COVID-19/metabolism , COVID-19/physiopathology , Female , Guinea Pigs , Humans , Inflammation/drug therapy , Inflammation/metabolism , Inflammation/physiopathology , Interleukin-6/antagonists & inhibitors , Male
11.
Mol Vis ; 28: 441-450, 2022.
Article in English | MEDLINE | ID: mdl-36601409

ABSTRACT

Purpose: To investigate the therapeutic effect of lipoxin A4 (LXA4) on Aspergillus fumigatus (A. fumigatus)-stimulated human corneal epithelial cells (HCECs). Methods: The cell counting kit-8 (CCK-8) was performed in HCECs to evaluate the toxicity of LXA4. A cell scratch test was used to assess the impact of LXA4 on the migration of HCECs. Enzyme-linked immunosorbent assay (ELISA), quantitative real-time polymerase chain reaction (qRT-PCR), and western blot were applied to examine the expression of inflammatory mediators in A. fumigatus-stimulated HCECs. The nuclear factor erythroid 2-related factor 2 (Nrf2) nuclear translocation and expression in HCECs were detected by immunofluorescence staining. Results: LXA4 at 0-10 nmol·L-1 (nM) had no significant cytotoxic effect on HCECs. LXA4 at a concentration of 1 nM and 10 nM significantly promoted the migration rate of HCECs. The mRNA and protein levels of pro-inflammatory mediators, including IL-1ß, TNF-α, and IL-6, were remarkably lower in the LXA4-treated group. LXA4 promoted the expression of Nrf2 and heme oxygenase 1 (HO-1) in A. fumigatus-stimulated HCECs compared with the PBS control group. Pretreatment with brusatol (BT, Nrf2 inhibitor) or Zine Protoporphyrin (Znpp, HO-1 inhibitor) receded the anti-inflammatory ability of LXA4. Conclusions: LXA4 plays a protective role in A. fumigatus-stimulated HCECs by inhibiting the expression of pro-inflammatory mediators through the Nrf2/HO-1 signaling pathway.


Subject(s)
Aspergillus fumigatus , Heme Oxygenase-1 , Humans , Heme Oxygenase-1/genetics , Heme Oxygenase-1/metabolism , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Signal Transduction , Inflammation , Epithelial Cells/metabolism , Inflammation Mediators/metabolism
12.
Int Immunopharmacol ; 96: 107785, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34162149

ABSTRACT

PURPOSE: To explore the anti-inflammatory effect of lipoxin A4 (LXA4) in Aspergillus fumigatus (A. fumigatus) keratitis and the underlying mechanisms. METHODS: In A. fumigatus keratitis mouse models, enzyme-linked immunosorbent assay (ELISA) was used to detect the level of LXA4. Clinical scores were utilized to evaluate fungal keratitis (FK) severity. Fungal load was assessed by plate count. Immunofluorescence staining, HE staining and myeloperoxidase (MPO) assays were carried out to evaluate the neutrophil infiltration and activity. In A. fumigatus infected mouse corneas and inactivated A. fumigatus-stimulated RAW264.7 cells, quantitative real time polymerase chain reaction (qRT-PCR) and ELISA were applied to assess the expression of pro-inflammatory mediators and anti-inflammatory factors.Reactive oxygen species (ROS) was determined by 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) staining in RAW264.7 cells. RESULTS: LXA4 level was significantly increased in mice with A. fumigatus keratitis. In an A. fumigatus keratitis mouse model, LXA4 treatment alleviated FK severity, reduced fungal load and repressed neutrophil infiltration and activity. Additionally, LXA4 inhibited the expression of pro-inflammatory mediators including IL-1ß, TNF-α, IL-6, cyclooxygenase-2 (COX-2), TLR-2, TLR-4, Dectin-1 and iNOS, and promoted the expression of anti-inflammatory factors IL-10 and Arg-1. In RAW264.7 cells, LXA4 receptor/formyl peptide receptor 2 (ALX/FPR2) blockade reversed the anti-inflammatory effect of LXA4. LXA4 suppressed inactivated A. fumigatus induced elevated ROS production in RAW264.7 cells, which was abrogated by ALX/FPR2 antagonist Boc-2. CONCLUSION: LXA4 ameliorated inflammatory response by suppressing neutrophil infiltration, downregulating the expression of pro-inflammatory mediators and ROS production through ALX/FPR2 receptor in A. fumigatus keratitis.


Subject(s)
Adaptor Proteins, Signal Transducing/immunology , Aspergillosis/immunology , Aspergillus fumigatus , Eye Infections, Fungal/immunology , Keratitis/immunology , Lipoxins/immunology , Receptors, Formyl Peptide/immunology , Animals , Cornea/immunology , Cytokines/genetics , Cytokines/immunology , Female , Inflammation/immunology , Mice , Mice, Inbred C57BL , Neutrophil Infiltration , RAW 264.7 Cells
13.
Eur J Pharmacol ; 901: 174077, 2021 Jun 15.
Article in English | MEDLINE | ID: mdl-33798601

ABSTRACT

This study investigated the hemodynamic effect of Bay 60-7550, a phosphodiesterase type 2 (PDE2) inhibitor, in healthy rat hearts both in vivo and ex vivo and its underlying mechanisms. In vivo rat left ventricular pressure-volume loop, Langendorff isolated rat heart, Ca2+ transient of left ventricular myocyte and Western blot experiments were used in this study. The results demonstrated that Bay 60-7550 (1.5 mg/kg, i. p.) increased the in vivo rat heart contractility by enhancing stroke work, cardiac output, stroke volume, end-diastolic volume, heart rate, and ejection fraction. The simultaneous aortic pressure recording indicated that the systolic blood pressure was increased and diastolic blood pressure was decreased by Bay 60-7550. Also, the arterial elastance which is proportional to the peripheral vessel resistance was significantly decreased. Bay 60-7550 (0.001, 0.01, 0.1, 1 µmol/l) also enhanced the left ventricular development pressure in non-paced and paced modes with a decrease of heart rate in non-paced model. Bay 60-7550 (1 µmol/l) increased SERCA2a activity and SR Ca2+ content and reduced SR Ca2+ leak rate. Furthermore, Bay 60-7550 (0.1 µmol/l) increased the phosphorylation of phospholamban at 16-serine without significantly changing the phosphorylation levels of phospholamban at 17-threonine and RyR2. Bay 60-7550 increased the rat heart contractility and reduced peripheral arterial resistance may be mediated by increasing the phosphorylation of phospholamban and dilating peripheral vessels. PDE2 inhibitors which result in a positive inotropic effect and a decrease in peripheral resistance might serve as a target for developing agents for the treatment of heart failure in clinical settings.


Subject(s)
Calcium-Binding Proteins/metabolism , Cardiotonic Agents/pharmacology , Cyclic Nucleotide Phosphodiesterases, Type 2/antagonists & inhibitors , Imidazoles/pharmacology , Phosphodiesterase Inhibitors/pharmacology , Triazines/pharmacology , Animals , Blood Pressure/drug effects , Calcium/metabolism , Hemodynamics/drug effects , In Vitro Techniques , Male , Myocardial Contraction/drug effects , Myocytes, Cardiac/drug effects , Phosphorylation , Rats , Rats, Sprague-Dawley , Sarcoplasmic Reticulum Calcium-Transporting ATPases/drug effects , Sarcoplasmic Reticulum Calcium-Transporting ATPases/metabolism , Vascular Resistance/drug effects , Ventricular Function, Left/drug effects
14.
Sheng Li Xue Bao ; 73(2): 275-285, 2021 Apr 25.
Article in Chinese | MEDLINE | ID: mdl-33903889

ABSTRACT

This study aimed to explore the positive inotropic effect of phosphodiesterase type 9 (PDE9) inhibitor PF-04449613 in ratsand its cellular and molecular mechanisms. The heart pressure-volume loop (P-V loop) analysis was used to detect the effects of PF-04449613 on rat left ventricular pressure-volume relationship, aortic pressures and peripheral vessel resistance in healthy rats. The Langendorff perfusion of isolated rat heart was used to explore the effects of PF-04449613 on heart contractility. The cardiomyocyte sarcoplasmic reticulum (SR) Ca2+ transients induced by field stimulation and caffeine were used to analyze the mechanism underlying the effect of PF-04449613 using Fluo-4 AM as a Ca2+ indicator. The results indicated as follows: (1) PF-04449613 (5.5 mg/kg, ip) significantly increased the stroke work, cardiac output, stroke volume, end-systolic pressure and ejection fraction (P < 0.05), and decreased the end-systolic volume, end-diastolic volume and end-diastolic pressure (P < 0.05). Meanwhile, the systolic blood pressure was increased and diastolic blood pressure and arterial elastance were decreased after PF-04449613 treatment (P < 0.05). (2) PF-04449613 (0.001, 0.01, 0.1, 1 µmol/L) significantly increased the left ventricular developed pressure (LVDP) in a concentration-dependent manner in vitro (P < 0.05). (3) PF-04449613 (5 µmol/L) significantly increased the amplitude of SR Ca2+ transients mediated by facilitating sarcoplasmic reticulum Ca2+-ATPase-2a (SERCA2a) (P < 0.05). (4) PF-04449613 (5 µmol/L) decreased the SR Ca2+ leak rate via ryanodine receptor 2 (RyR2) (P < 0.05). In conclusion, PF-04449613 exerted positive inotropic effect both in vivo and in vitro by enhancing SERCA2a activity.


Subject(s)
Calcium , Phosphodiesterase Inhibitors , Animals , Calcium/metabolism , Myocardial Contraction , Myocytes, Cardiac/metabolism , Phosphoric Diester Hydrolases , Rats , Ryanodine Receptor Calcium Release Channel , Sarcoplasmic Reticulum
15.
Clin Exp Pharmacol Physiol ; 48(5): 686-696, 2021 05.
Article in English | MEDLINE | ID: mdl-32931027

ABSTRACT

This study was to investigate the inotropic effect of atractylodin and its underlying mechanism. The cardiac pressure-volume loop (P-V loop), Langendroff-perfused isolated rat heart, patch-clamp, Ca2+ transient and western blot techniques were used. The results demonstrated that atractylodin (3 mg/kg, ip) remarkably increased the left ventricular stroke work, cardiac output, stroke volume, heart rate, ejection fraction, end-systolic pressure, peak rates of rise and fall of left ventricular pressures (+dP/dtmax , -dP/dtmax ), the slopes of end-systolic pressure-volume relationship (also named as end-systolic elastance, Ees) and reducing end-systolic volume and end-diastolic volume in the in vivo rat study. Also, atractylodin (3 mg/kg, ip) significantly decreased diastolic blood pressure and the arterial elastance (Ea) without significant systolic blood pressure change. In addition, atractylodin (0.1, 1, 10 µmol/L) also increased the isolated rat heart left ventricular developed pressure which is the difference between the systolic and diastolic pressure in non-pacing and pacing modes. Furthermore, JMV-2959 (1 µmol/L), a ghrelin receptor unbiased antagonist, blocked the increased left ventricular developed pressure of atractylodin in isolated rat hearts. Finally, atractylodin (5 µmol/L) increased the amplitude of Ca2+ transient by enhancing SERCA2a activity, the sarcoplasmic reticulum Ca2+ content and the phosphorylation of phospholamban at 16-serine. These results demonstrated that atractylodin had a positive inotropic effect by enhancing SERCA2a activity which might be mediated by acting ghrelin receptor in myocardium. In conclusion, atractylodin which had the positive inotropic effect and decreased diastolic blood pressure might serve as an agent for the treatment of heart failure in clinical settings.


Subject(s)
Furans , Animals , Myocardial Contraction , Rats , Sarcoplasmic Reticulum , Ventricular Function, Left
16.
Exp Physiol ; 105(3): 477-488, 2020 03.
Article in English | MEDLINE | ID: mdl-31912915

ABSTRACT

NEW FINDINGS: What is the central question of this study? The therapeutic effect of ivabradine on patients with chronic heart failure and chronic stable angina pectoris is mediated through a reduction in heart rate: what are the haemodynamic characteristics and the mechanism of the inotropic effect? What is the main finding and its importance? Ivabradine has a positive inotropic effect and lowers the heart rate both in vivo and in vitro. These effects are likely mediated by ivabradine's significant increase of the fast component rate constant mediated by sarcoplasmic/endoplasmic reticulum calcium ATPase 2a and decrease of the slow component rate constant that is mediated by the Na+ /Ca2+ exchanger and sarcolemmal Ca2+ -ATPase during the Ca2+ transient decay phase. ABSTRACT: Ivabradine's therapeutic effect is mediated by a reduction of the heart rate; however, its haemodynamic characteristics and the mechanism of its inotropic effect are poorly understood. We aimed to investigate the positive inotropic effect of ivabradine and its underlying mechanism. The results demonstrated that ivabradine increased the positive inotropy of the rat heart in vivo by increasing the stroke work, cardiac output, stroke volume, end-diastolic volume, end-systolic pressure, ejection fraction, ±dP/dtmax , left ventricular end-systolic elastance and systolic blood pressure without altering the diastolic blood pressure and arterial elastance. This inotropic effect was observed in both non-paced and paced rat isolated heart. Ivabradine increased the Ca2+ transient amplitude and the reuptake rates of sarcoplasmic/endoplasmic reticulum calcium ATPase 2a (SERCA2a), lowered the diastolic Ca2+ level and suppressed the combined extrusion rate of the Na+ /Ca2+ exchanger and the sarcolemmal Ca2+ -ATPase. In addition, ivabradine widened the action potential duration, hyperpolarized the resting membrane potential, increased sarcoplasmic reticulum Ca2+ content and reduced Ca2+ leak. Overall, ivabradine had a positive inotropic effect brought about by enhanced SERCA2a activity, which might be mediated by increased phospholamban phosphorylation. The positive inotropic effect along with the lowered heart rate underlies ivabradine's therapeutic effect in heart failure.


Subject(s)
Calcium/metabolism , Ivabradine/pharmacology , Sarcoplasmic Reticulum Calcium-Transporting ATPases/metabolism , Animals , Calcium-Binding Proteins/metabolism , Heart Failure/metabolism , Heart Rate/drug effects , Heart Ventricles/drug effects , Heart Ventricles/metabolism , Male , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/metabolism , Rats , Rats, Sprague-Dawley , Sarcoplasmic Reticulum/drug effects , Sarcoplasmic Reticulum/metabolism , Sodium-Calcium Exchanger/metabolism , Stroke Volume/drug effects
17.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 36(5): 408-413, 2020 Sep.
Article in Chinese | MEDLINE | ID: mdl-33629552

ABSTRACT

Objective: To explore the positive inotropic effect of atractylodin which is major active component of Rhzoma Atractylodis Lanceae and its underlying mechanism. Methods: For in vivo study, six male SD rats were randomly selected for the heart pressure-volume loop (P-V loop) experiment. The effects of atractylodin (3 mg/kg, intraperitoneal injection) on hemodynamic parameters such as LVDP (left ventricular developed pressure), SW (stroke work), HR (heart rate), CO (cardiac output), SBP (systolic blood pressure) and DBP (diastolic blood pressure) were analyzed. For in vitro study, left ventricular developed pressure (LVDP) from the Langendroff-perfused isolated rat heart was analyzed before as the control and after atractylodin perfusion. For in vitro study, the effects of atractylodin and atractylodin with H89 (PKA inhibitor) or KN-93 (CaMKII inhibitor or Calyculin A (PP1, PP2A inhibitor) on LVDP were analyzed. The experiments were separated into four parts with six isolated hearts for each as follows: (1) Control→0.1→1→10 µmol/L atractylodin; (2) Control→200 nmol/L H89 (PKA inhibitor)→200 nmol/L H89+10 µmol/L atractylodin; (3) Control→500 nmol/L KN-93 (CaMKII inhibitor)→500 nmol/L KN-93+10 µmol/L atractylodin; (4) Control→10 nmol/L Calyculin A (PP1, PP2A inhibitor)→10 nmol/L Calyculin A+10 µmol/L atractylodin. For the study of rat left ventricular myocyte Ca2+ transient induced by field stimulation, the experiment design was the same as in vitro study. The six cells from the different rats were used for each part experiment. Results: ① Atractylodin (3 mg/kg) significantly increased the heart rate, cardiac output and stroke work (P<0.05) and decreased the diastolic blood pressure (P<0.05). ② Atractylodin (0.1, 1, 10 µmol/L) significantly increased the LVDP in a concentration dependent manner (P<0.05). The positive inotropic effect of atractylodin could be blocked by PKA inhibitor H89. ③ Atractylodin (10 µmol/L) significantly increased the amplitude of SR Ca2+ transient amplitude mediated by facilitating sarcoplasmic reticulum SERCA2a. The enhanced amplitude of SR Ca2+ transient could be blocked by PKA inhibitor H89. Conclusion: Atractylodin had positive inotropic effect in rat heart both in vivo and in vitro with decreased diastolic blood pressure and its underlying mechanism was mediated by PKA. Based on the fact that the atractylodin exerted its positive inotropic effect was mediated by PKA, the PKA-SERCA2a signaling pathway might be the mechanism of the atractylodin's positive inotropy.


Subject(s)
Furans , Myocytes, Cardiac , Animals , Calcium , Calcium-Calmodulin-Dependent Protein Kinase Type 2 , Furans/pharmacology , Male , Myocardial Contraction , Rats , Rats, Sprague-Dawley
18.
Int J Nurs Pract ; 26(2): e12761, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31328348

ABSTRACT

AIM: To establish a care bundle in spinal cord injury patients with neurogenic bladder to avoid upper urinary tract damage and to provide guidance for health care staff in use of nonsurgical and nonpharmacological adjunctive strategies to improve patients' clinical outcomes. BACKGROUND: Prevention of upper urinary tract damage is critical in the management of spinal cord injury patients with a neurogenic bladder, but there are no authoritative guidelines or high-quality randomized controlled trials. DESIGN: The study was conducted on the basis of Fulbrook and Mooney's seven-step method for care bundle development. DATA SOURCES: The databases PubMed, Embase, Science Citation Index, the Cumulative Index to Nursing and Allied Health Literature, the National Guideline Clearinghouse, the Cochrane Library, China Biology Medicine, China National Knowledge Infrastructure, and China Dissertation Database were searched from the date of each database's inception to April 2017. REVIEW METHODS: We evaluated the literature according to the Joanna Briggs Institute evidence pre-ranking and grade recommendation system (2014 version). The results were examined using a self-designed data extraction. RESULTS: A three-element cluster including clean intermittent catheterization, bladder function training, and transcutaneous low-frequency pulsed electrical stimulation was formed. CONCLUSION: The development of this bundle can provide a scientific basis for effective prevention of neurogenic upper urinary tract damage in clinical practice.


Subject(s)
Spinal Cord Injuries/complications , Urinary Bladder, Neurogenic/complications , Urinary Tract/physiopathology , China , Humans , Male , Spinal Cord Injuries/physiopathology , Urinary Bladder, Neurogenic/physiopathology
19.
Front Microbiol ; 10: 2211, 2019.
Article in English | MEDLINE | ID: mdl-31681182

ABSTRACT

Antimicrobial peptides (AMPs) represent the largest group of endogenous compounds and serves as a novel alternative to traditional antibiotics for the treatment of pathogenic microorganisms. Moricin is an important α-helical AMP plays a crucial role in insect humoral defense reactions. The present study was designed to identify and characterize novel AMP moricin (Px-Mor) from diamondback moth (Plutella xylostella) and tested its activity against bacterial and fungal infection including the opportunistic human pathogen Aureobasidium pullulans. Molecular cloning of Px-Mor using rapid amplification of cDNA ends revealed a 482 bp full length cDNA with 198 bp coding region. The deduced protein sequence contained 65 amino acids, and the mature peptides contained 42 amino acid residues with a molecular mass of 4.393 kDa. Expression analysis revealed that Px-Mor was expressed throughout the life cycle of P. xylostella with the highest level detectable in the fourth instar and prepupa stage. Tissue specific distribution showed that Px-Mor was highly expressed in fat body and hemocyte. In vitro, antimicrobial assays indicated that Px-Mor exhibited a broad antimicrobial spectrum against Gram positive bacteria (GPB), Gram negative bacteria (GNB) and fungi. Moreover, scanning electron microscopy and transmission electron microscopy (TEM) revealed that Px-Mor can cause obvious morphological alterations in A. pullulans, which demonstrated its powerful effect on the mycelia growth inhibition. Taken together, these results indicate that Px-Mor plays an important role in the immune responses of P. xylostella and can be further exploited as an antimicrobial agent against various diseases including for the treatment of A. pullulans infection.

20.
Front Pharmacol ; 10: 221, 2019.
Article in English | MEDLINE | ID: mdl-30967774

ABSTRACT

This study was designed to investigate the hemodynamic effect of rolipram, a phosphodiesterase type 4 (PDE4) inhibitor, in normal rat hearts both in vivo and in vitro and its underlying mechanism. The pressure-volume loop, isolated heart, and Ca2+ transients triggered by field stimulation or caffeine were used to analyze the hemodynamic mechanism of rolipram. The results demonstrated that rolipram (3 mg/kg, ip) significantly increased the in vivo rat heart contractility by enhancing stroke work, cardiac output, stroke volume, end-systolic volume, end-diastolic volume, end-systolic pressure, heart rate, ejection fraction, peak rate of rise of left pressure (+dp/dtmax), the slopes of end-systolic pressure-volume relationship (slope of ESPVR) named as left ventricular end-systolic elastance, and reduced the slopes of end-diastolic pressure-volume relationship (slope of EDPVR). Meanwhile, the systolic blood pressure, diastolic blood pressure, and pulse pressure were significantly enhanced by rolipram. Also, rolipram deviated normal ventricular-arterial coupling without changing the arterial elastance. Furthermore, rolipram (0.1, 1, 10 µM) also exerted positive inotropic effect in isolated rat hearts by increasing the left ventricular development pressure, and +dp/dtmax in non-paced and paced modes. Rolipram (10 µM) increased the SERCA2a activity, Ca2+ content, and Ca2+ leak rate without changing diastolic Ca2+ level. Rolipram had significant positive inotropic effect with less effect on peripheral vascular elastance and its underlying mechanism was mediated by increasing SERCA2a activity. PDE4 inhibition by rolipram resulted in a positive inotropic effect and might serve as a target for developing agents for the treatment of heart failure in clinical settings.

SELECTION OF CITATIONS
SEARCH DETAIL
...