86 results on '"Guohua Gong"'
Search Results
2. Long non‐coding RNA Sox2OT promotes coronary microembolization‐induced myocardial injury by mediating pyroptosis
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Liying Xuan, Danni Fu, Dong Zhen, Dongsong Bai, Lijun Yu, and Guohua Gong
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Coronary microembolization ,Myocardial injury ,Long non‐coding RNA Sox2 overlapping transcript ,microRNA‐23b ,TLR4 ,NF‐κB ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Objective As a common complication of coronary microembolization (CME), myocardial injury (MI) implies high mortality. Long non‐coding RNAs (lncRNAs) are rarely studied in CME‐induced MI. Herein, this study intended to evaluate the role of lncRNA Sox2 overlapping transcript (Sox2OT) in CME‐induced MI. Methods The CME rat models were successfully established by injection of microemboli. Rat cardiac functions and MI were observed by ultrasonic electrocardiogram, HE staining, and HBFP staining. Functional assays were utilized to test the inflammatory responses, oxidative stress, and pyroptosis using reverse transcription quantitative polymerase chain reaction, Western blotting, immunohistochemistry, immunofluorescence, and ELISA. Dual‐luciferase reporter gene assay and RNA immunoprecipitation were conducted to clarify the targeting relations between Sox2OT and microRNA (miRNA)‐23b and between miR‐23b and toll‐like receptor 4 (TLR4). Results Rat CME disrupted the cardiac functions and induced inflammatory responses and oxidative stress, and activated the nuclear factor‐kappa B (NF‐κB) pathway and pyroptosis (all P
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- 2022
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3. Mitochondrial autophagy: molecular mechanisms and implications for cardiovascular disease
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Anqi Li, Meng Gao, Bilin Liu, Yuan Qin, Lei chen, Hanyu Liu, Huayan Wu, and Guohua Gong
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Cytology ,QH573-671 - Abstract
Abstract Mitochondria are highly dynamic organelles that participate in ATP generation and involve calcium homeostasis, oxidative stress response, and apoptosis. Dysfunctional or damaged mitochondria could cause serious consequences even lead to cell death. Therefore, maintaining the homeostasis of mitochondria is critical for cellular functions. Mitophagy is a process of selectively degrading damaged mitochondria under mitochondrial toxicity conditions, which plays an essential role in mitochondrial quality control. The abnormal mitophagy that aggravates mitochondrial dysfunction is closely related to the pathogenesis of many diseases. As the myocardium is a highly oxidative metabolic tissue, mitochondria play a central role in maintaining optimal performance of the heart. Dysfunctional mitochondria accumulation is involved in the pathophysiology of cardiovascular diseases, such as myocardial infarction, cardiomyopathy and heart failure. This review discusses the most recent progress on mitophagy and its role in cardiovascular disease.
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- 2022
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4. The complete chloroplast genome sequence of Rhaponticum uniflorum, the first of the genus Rhaponticum
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Hu Boqin, Qiang Zhou, Liqiang Wang, Mei Jiang, Guohua Gong, Chang Liu, and Chengxi Wei
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rhaponticum uniflorum ,chloroplast genome ,phylogeny ,Genetics ,QH426-470 - Abstract
Rhaponticum uniflorum is commonly used as a source for traditional medicines with the main effect of clearing heat. Here, we sequenced the complete chloroplast (cp) genome of R. uniflorum to develop molecular markers for taxonomic classification and species determination of R. uniflorum. It was 152,760 bp in size and has a typical circular structure, including a pair of inverted repeats with 25,205 bp, a large single-copy region with 83,687 bp, and a small single copy region with 18,663 bp. The genome encodes 110 unique genes, including 80 protein-coding, four rRNA and 26 tRNA genes. Phylogenomic analysis shows that R. uniflorum is closely related to the Saussurea. The study is useful for phylogenetic and population genetic studies of Rhaponticum plants.
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- 2022
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5. PGC-1α-Mediated Mitochondrial Quality Control: Molecular Mechanisms and Implications for Heart Failure
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Lei Chen, Yuan Qin, Bilin Liu, Meng Gao, Anqi Li, Xue Li, and Guohua Gong
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PGC-1α ,mitochondrial biogenesis ,mitochondrial quality control ,heart failure ,mitochondrial dynamics ,Biology (General) ,QH301-705.5 - Abstract
Mitochondria with structural and functional integrity are essential for maintaining mitochondrial function and cardiac homeostasis. It is involved in the pathogenesis of many diseases. Peroxisome proliferator-activated receptor γ coactivator 1 α (PGC-1α), acted as a transcriptional cofactor, is abundant in the heart, which modulates mitochondrial biogenesis and mitochondrial dynamics and mitophagy to sustain a steady-state of mitochondria. Cumulative evidence suggests that dysregulation of PGC-1α is closely related to the onset and progression of heart failure. PGC-1α deficient-mice can lead to worse cardiac function under pressure overload compared to sham. Here, this review mainly focuses on what is known about its regulation in mitochondrial functions, as well as its crucial role in heart failure.
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- 2022
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6. Correction: Ethyl ferulate contributes to the inhibition of the inflammatory responses in murine RAW 264.7 macrophage cells and acute lung injury in mice.
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Yu Wang, Xuan Zhang, Linger Li, Zhao Zhang, Chengxi Wei, and Guohua Gong
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Medicine ,Science - Abstract
[This corrects the article DOI: 10.1371/journal.pone.0251578.].
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- 2022
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7. Calibration and measurement of mitochondrial pH in intact adult rat cardiomyocytes
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Meng Gao, Yuan Qin, Anqi Li, Hanyu Liu, Lei Chen, Bilin Liu, Ying Zhang, Yufei Gao, and Guohua Gong
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Cell Biology ,Metabolism ,Microscopy ,Molecular/Chemical Probes ,Science (General) ,Q1-390 - Abstract
Summary: Mitochondrial pH is a vital parameter of the mitochondrial environment, which determines the rate of many mitochondrial functions, including metabolism, membrane potential, fate, etc. Abnormal mitochondrial pH is always closely related to the health status of cells. Analyzing mitochondrial pH can serve as a proxy for mitochondrial and cellular function. This protocol describes the use of SNARF-1 AM, a pH-sensitive fluorophore, to measure mitochondrial pH. This protocol details the steps to evaluate mitochondrial pH in live adult cardiomyocytes using confocal microscopy. The protocol can be adapted to other adherent cell types.For complete details on the use and execution of this protocol, please refer to Wei-LaPierre et al. (2013).
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- 2021
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8. Mitochondrial Fusion Protein Mfn2 and Its Role in Heart Failure
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Lei Chen, Bilin Liu, Yuan Qin, Anqi Li, Meng Gao, Hanyu Liu, and Guohua Gong
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Mfn2 ,mitochondria fusion ,endoplasmic reticulum–mitochondria contacts ,mitophagy ,heart failure ,Biology (General) ,QH301-705.5 - Abstract
Mitofusin 2 (Mfn2) is a transmembrane GTPase located on the mitochondrial outer membrane that contributes to mitochondrial network regulation. It is an essential multifunctional protein that participates in various biological processes under physical and pathological conditions, including mitochondrial fusion, reticulum–mitochondria contacts, mitochondrial quality control, and apoptosis. Mfn2 dysfunctions have been found to contribute to cardiovascular diseases, such as ischemia-reperfusion injury, heart failure, and dilated cardiomyopathy. Here, this review mainly focuses on what is known about the structure and function of Mfn2 and its crucial role in heart failure.
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- 2021
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9. Ethyl ferulate contributes to the inhibition of the inflammatory responses in murine RAW 264.7 macrophage cells and acute lung injury in mice.
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Yu Wang, Xuan Zhang, Linger Li, Zhao Zhang, Chengxi Wei, and Guohua Gong
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Medicine ,Science - Abstract
BackgroundEthyl ferulate (EF) is a derivative of ferulic acid (FA), which is a monomeric component purified from the traditional medicinal herb Ferula, but its effects have not been clear yet. The purpose of this study was to evaluate whether EF can reduce inflammation levels in macrophages by regulating the Nrf2-HO-1 and NF-кB pathway.MethodsThe LPS-induced raw 264.7 macrophage cells model was used to determine the anti-inflammatory and anti-oxidative stress effects of EF. The levels of IL-1β, IL-6, TNF-α and PGE2 were analyzed by ELISA. The mRNA and protein of COX-2, iNOS, TNF-α, IL-6, HO-1 and Nrf2 were identified by RT-PCR analysis and western blotting. Intracellular ROS levels were assessed with DCFH oxidation staining. The expressions of NF-кB p-p65 and Nrf2 were analyzed by immunofluorescence assay. The inhibitory effect of Nrf2 inhibitor ML385 (2μM) on mediatation of antioxidant activity by raw 264.7 macrophage cells was evaluated. The effect of EF was confirmed in acute lung injury mice model.ResultsIn our research, EF reduced the expression of iNOS, COX2 and the production of PGE2. EF could inhibit the production of pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α) in lipopolysaccharide (LPS) stimulated macrophages and decreased expression of IL-6 and TNF-α in LPS stimulated macrophages. Furthermore, EF inhibited NF-кB p65 from transporting to the nucleus, decreased the expression of p-IкBα, significantly decreased the level of intracellular reactive oxygen species (ROS) and activated Nrf2/HO-1 pathways. EF could attenuate the degree of leukocyte infiltration, reduced MPO activity, mRNA levels and secretion of TNF-α and IL-6 in vivo. EF exhibited potent protective effects against LPS-induced acute lung injury in mice.ConclusionsCollectively, our data showed that EF relieved LPS-induced inflammatory responses by inhibiting NF-κB pathway and activating Nrf2/HO-1 pathway, known to be involved in the regulation of inflammatory responses by Nrf2.
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- 2021
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10. Mitochondrial Dynamics in Adult Cardiomyocytes and Heart Diseases
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Anqi Li, Meng Gao, Wenting Jiang, Yuan Qin, and Guohua Gong
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heart ,mitochondrial fusion ,mitochondrial fission ,dynamics ,mature cardiomyocytes ,Biology (General) ,QH301-705.5 - Abstract
Mitochondria are the powerhouse organelles of cells; they participate in ATP generation, calcium homeostasis, oxidative stress response, and apoptosis. Thus, maintenance of mitochondrial function is critical for cellular functions. As highly dynamic organelles, the function of mitochondria is dynamically regulated by their fusion and fission in many cell types, which regulate mitochondrial morphology, number, distribution, metabolism, and biogenesis in cells. Mature rod-shaped cardiomyocytes contain thousands of end-to-end contacted spheroid mitochondria. The movement of mitochondria in these cells is limited, which hinders the impetus for research into mitochondrial dynamics in adult cardiomyocytes. In this review, we discuss the most recent progress in mitochondrial dynamics in mature (adult) cardiomyocytes and the relationship thereof with heart diseases.
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- 2020
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11. Modified Protocol for A Mouse Heart Failure Model Using Minimally Invasive Transverse Aortic Constriction
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Bilin Liu, Anqi Li, Meng Gao, Yuan Qin, and Guohua Gong
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Cell Biology ,Model Organisms ,Science (General) ,Q1-390 - Abstract
Summary: Here, we present a modified protocol for a mouse heart failure (HF) model using minimally invasive transverse aortic constriction (miTAC). miTAC is a more effective method in mice than the standard open-chest transverse aortic constriction (TAC) to generate an HF model. miTAC does not require the cutting of the ribs or tracheal intubation with artificial ventilation; it also has a higher survival rate. The successful outcome of the HF model can be verified using transthoracic echocardiography and histology.For complete details on the use and execution of this protocol, please refer to Hu et al. (2003) and Richards et al. (2019).
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- 2020
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12. Protocol for Measurement of Oxygen Consumption Rate In Situ in Permeabilized Cardiomyocytes
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Meng Gao, Anqi Li, Yuan Qin, Bilin Liu, and Guohua Gong
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Science (General) ,Q1-390 - Abstract
Summary: Analysis of mitochondrial respiration function represented by the oxygen consumption rate is necessary for assessing mitochondrial respiration function. This protocol describes steps to evaluate the respiration function of mitochondria in situ in saponin-permeabilized cardiomyocytes. In permeabilized cells, mitochondria are in a relatively integrated cellular system, and mitochondrial respiration is more physiologically relevant than isolated mitochondria.For complete details on the use and execution of this protocol, please refer to Gong et al. (2015a) and Gong et al. (2015b).
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- 2020
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13. Protocol for Imaging of Mitoflashes in Live Cardiomyocytes
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Anqi Li, Yuan Qin, Meng Gao, Wenting Jiang, Bilin Liu, Xiangang Tian, and Guohua Gong
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Science (General) ,Q1-390 - Abstract
Summary: We describe a protocol for imaging a mitochondrial fluorescence transient increase event (Mitoflash) in live cardiomyocytes using a confocal microscope. Mitoflash, detected by mitochondria-targeted circularly permuted fluorescent protein (mt-cpYFP), can be used to assess mitochondrial respiration function in situ. The protocol is also suitable for live-cell imaging of other adherent cells, including fibroblasts and hepatocytes.For complete details on the use and execution of this protocol, please refer to Gong et al. (2014) and Gong et al. (2015).
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- 2020
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14. Protocol for Isolation of Viable Adult Rat Cardiomyocytes with High Yield
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Xiangang Tian, Meng Gao, Anqi Li, Bilin Liu, Wenting Jiang, Yuan Qin, and Guohua Gong
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Science (General) ,Q1-390 - Abstract
Summary: Isolation of high-quantity and high-quality ventricular cardiomyocytes from adult rats is critical to study heart physiology and pathology and for drug toxicity screening. It remains challenging to produce a high yield of viable cardiomyocytes from rats. Here, we present our modified enzymatic digestion protocol that relies on the Langendorff device to generate large numbers of viable cardiomyocytes consistently. The most critical parts of this protocol are the selection of rat age and digestion time to obtain viable cardiomyocytes.For complete details on the use and execution of this protocol, please refer to Liu et al. (2019) and Qin et al. (2020).
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- 2020
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15. The Combination of Paraformaldehyde and Glutaraldehyde Is a Potential Fixative for Mitochondria
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Yuan Qin, Wenting Jiang, Anqi Li, Meng Gao, Hanyu Liu, Yufei Gao, Xiangang Tian, and Guohua Gong
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mitochondria ,fixative ,mitochondrial morphology ,paraformaldehyde ,glutaraldehyde ,Microbiology ,QR1-502 - Abstract
Mitochondria are highly dynamic organelles, constantly undergoing shape changes, which are controlled by mitochondrial movement, fusion, and fission. Mitochondria play a pivotal role in various cellular processes under physiological and pathological conditions, including metabolism, superoxide generation, calcium homeostasis, and apoptosis. Abnormal mitochondrial morphology and mitochondrial protein expression are always closely related to the health status of cells. Analysis of mitochondrial morphology and mitochondrial protein expression in situ is widely used to reflect the abnormality of cell function in the chemical fixed sample. Paraformaldehyde (PFA), the most commonly used fixative in cellular immunostaining, still has disadvantages, including loss of antigenicity and disruption of morphology during fixation. We tested the effect of ethanol (ETHO), PFA, and glutaraldehyde (GA) fixation on cellular mitochondria. The results showed that 3% PFA and 1.5% GA (PFA-GA) combination reserved mitochondrial morphology better than them alone in situ in cells. Mitochondrial network and protein antigenicity were well maintained, indicated by preserved MitoTracker and mitochondrial immunostaining after PFA-GA fixation. Our results suggest that the PFA-GA combination is a valuable fixative for the study of mitochondria in situ.
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- 2021
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16. CaMKII induces permeability transition through Drp1 phosphorylation during chronic β-AR stimulation
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Shangcheng Xu, Pei Wang, Huiliang Zhang, Guohua Gong, Nicolas Gutierrez Cortes, Weizhong Zhu, Yisang Yoon, Rong Tian, and Wang Wang
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Science - Abstract
β-adrenergic receptor signaling induces mitochondrial permeability transition pore (mPTP) opening. Here, Xuet al. show that this effect is mediated by phosphorylation of mitochondrial fission protein Drp1 by CamKII, which increases the frequency of transient mPTP opening.
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- 2016
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17. Identification and prognostic value of anterior gradient protein 2 expression in breast cancer based on tissue microarray
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Jilong Guo, Guohua Gong, and Bin Zhang
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Breast cancer has attracted substantial attention as one of the major cancers causing death in women. It is crucial to find potential biomarkers of prognostic value in breast cancer. In this study, the expression pattern of anterior gradient protein 2 in breast cancer was identified based on the main molecular subgroups. Through analysis of 69 samples from the Gene Expression Omnibus database, we found that anterior gradient protein 2 expression was significantly higher in non–triple-negative breast cancer tissues compared with normal tissues and triple-negative breast cancer tissues (p
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- 2017
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18. Inhibition of mitochondrial superoxide promotes the development of hiPS-CMs during differentiation
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Anqi Li, Meng Gao, Bilin Liu, Yuan Qin, Lei Chen, Hanyu Liu, and Guohua Gong
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Superoxides ,Physiology (medical) ,Induced Pluripotent Stem Cells ,Humans ,Cell Differentiation ,Myocytes, Cardiac ,Lipids ,Biochemistry ,Antioxidants ,Mitochondria - Abstract
The redox state is a crucial determinant of the maturation transition of cardiomyocytes in vivo. Mitochondria, the primary site of superoxide generation, are very sensitive to various stimulations, including oxygen and nutrient supply. How mitochondrial superoxide affects the differentiation and development of induced pluripotent stem cell (iPSC)-derived cardiac myocytes (iPS-CMs) is not completely clear. To address the questions, we monitored the superoxide level during the differentiation and development of human iPS-CMs using MitoSOX. Mitochondria-targeted antioxidant Mito-TEMPO was used to treat hiPS-CMs in the differentiation period. We found that mitochondrial superoxide generation was dramatically enhanced during the differentiation and early development of iPS-CMs. Increased oxidative stress induced oxidative damage to macromolecules in iPS-CMs, such as lipids, proteins, and DNA. Mito-TEMPO protected mitochondrial functions, alleviated oxidative damage to lipids, proteins, and DNA and improved cellular structure and fatty acid utilization. Our findings confirmed that iPS-CM suffered from oxidative stress during differentiation and that mitochondrial-targeted antioxidant is beneficial for the maturation of iPS-CMs.
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- 2022
19. Synthesis and Evaluation of Bakuchiol Derivatives as Potent Anti-inflammatory Agents in Vitro and in Vivo
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Qianqian Ma, Ming Bian, Guohua Gong, Chunmei Bai, Chunyan Liu, Chengxi Wei, Zhe-shan Quan, and Huan-huan Du
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Pharmacology ,Complementary and alternative medicine ,Organic Chemistry ,Drug Discovery ,Pharmaceutical Science ,Molecular Medicine ,Analytical Chemistry - Published
- 2022
20. Visualizing Mitophagy with Fluorescent Dyes for Mitochondria and Lysosome
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Guohua Gong, Meng Gao, Lei Chen, Yuan Qin, Anqi Li, and Bilin Liu
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General Immunology and Microbiology ,General Chemical Engineering ,General Neuroscience ,Mitophagy ,Apoptosis ,Lysosomes ,General Biochemistry, Genetics and Molecular Biology ,Fluorescent Dyes ,Mitochondria - Abstract
Mitochondria, being the powerhouses of the cell, play important roles in bioenergetics, free radical generation, calcium homeostasis, and apoptosis. Mitophagy is the primary mechanism of mitochondrial quality control and is generally studied using microscopic observation, however in vivo mitophagy assays are difficult to perform. Evaluating mitophagy by imaging live organelles is an alternative and necessary method for mitochondrial research. This protocol describes the procedures for using the cell-permeant green-fluorescent mitochondria dye MitoTracker Green and the red-fluorescent lysosome dye LysoTracker Red in live cells, including the loading of the dyes, visualization of the mitochondria and the lysosome, and expected outcomes. Detailed steps for the evaluation of mitophagy in live cells, as well as technical notes about microscope software settings, are also provided. This method can help researchers observe mitophagy using live-cell fluorescent microscopy. In addition, it can be used to quantify mitochondria and lysosomes and assess mitochondrial morphology.
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- 2022
21. Design, Synthesis, and In Vitro and In Vivo Biological Evaluation of Limonin Derivatives for Anti-Inflammation Therapy
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Huan-huan Du, Zhe-Shan Quan, Qian-qian Ma, Chengxi Wei, Pang Lei, Ming Bian, Chunmei Bai, and Guohua Gong
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Lipopolysaccharide ,medicine.drug_class ,Limonin ,Biological activity ,General Chemistry ,Pharmacology ,Anti-inflammatory ,In vitro ,Proinflammatory cytokine ,chemistry.chemical_compound ,chemistry ,In vivo ,medicine ,lipids (amino acids, peptides, and proteins) ,General Agricultural and Biological Sciences ,RAW 264.7 Cells - Abstract
In this study, limonin derivatives were used to design new anti-inflammatory compounds with high pharmacological activity and low toxicity. A total of 23 new limonin derivatives were discovered, synthesized, and screened for their anti-inflammatory activity against lipopolysaccharide (LPS)-treated RAW 264.7 cells. Of them, compound f4 was found to be the most active, with a higher efficiency compared with limonin and celecoxib. Subsequently, we studied the mechanism underlying the activity of f4 and found that it inhibited proinflammatory cytokines by blocking the NF-κB/MAPK signaling pathway in LPS-treated RAW 264.7 cells as well as mice. In conclusion, f4 may be a promising anti-inflammatory lead compound.
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- 2021
22. Letter to the editor: Compromised hepatic mitochondrial fatty acid oxidation and reduced markers of mitochondrial turnover in human NAFLD
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Yuan Qin, Anqi Li, Bilin Liu, Meng Gao, and Guohua Gong
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Hepatology ,Liver ,Non-alcoholic Fatty Liver Disease ,Fatty Acids ,Humans ,Mitochondrial Turnover ,Lipid Metabolism ,Oxidation-Reduction - Published
- 2022
23. Ethanol extracts of Rhaponticum uniflorum (L.) DC inflorescence ameliorate LPS-mediated acute lung injury by alleviating inflammatory responses via the Nrf2/HO-1 signaling pathway
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Dong Zhen, Chunyan Liu, Tianpeng Huang, Danni Fu, Xue Bai, Qianqian Ma, Mingyang Jiang, and Guohua Gong
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Pharmacology ,Inflammation ,Lipopolysaccharides ,Mice, Inbred BALB C ,Kelch-Like ECH-Associated Protein 1 ,Ethanol ,Interleukin-6 ,NF-E2-Related Factor 2 ,Plant Extracts ,Tumor Necrosis Factor-alpha ,Acute Lung Injury ,Anti-Inflammatory Agents ,NF-kappa B ,Membrane Proteins ,Asteraceae ,Leuzea ,Toll-Like Receptor 4 ,Mice ,Drug Discovery ,Animals ,Inflorescence ,Heme Oxygenase-1 ,Signal Transduction - Abstract
Rhaponticum uniflorum (L.) DC is a member of the Compositae family. Loulu flowers (LLF) is the inflorescence of this plant, which is a commonly used Mongolian medicine for the treatment of inflammatory diseases due to its heat-clearing and detoxifying properties. It is used caused by. However, its anti-inflammatory mechanisms are not clear.We investigated whether ethanol extracts of LLF can alleviate LPS-induced acute lung injury and explored the mechanism involved.BALB/C mice were intragastrically administered with sodium carboxymethyl cellulose (0.5%, 1 mL/100 g) or ethanol extracts of LLF at a dose of 100, 200, and 400 mg/kg, once daily, for 3 days. Subsequently, mice models of acute lung injury were established by LPS and used for the determination of anti-inflammatory effects of LLF. After 6 h of treatment, mice were sacrificed to collect lung tissues and bronchoalveolar lavage fluid (BALF). HE staining assay was performed on the tissues for pathological analysis. The ELISA test was conducted to measure NO, IL-6, TNF-α, MPO, SOD, CAT, MDA and GSH-PX levels. The expression level of proteins associated with the Nrf2/HO-1 and MAPK/NF-κB signaling pathways were determined using Western blot analysis. Levels of F4/80 and Nrf2 in lungs were quantified using immunohistochemistry.Oral administration of LLF extracts alleviated LPS-induced pathological alterations, reduced lung W/D weight ratio, decreased levels of TP, pro-inflammatory factors (TNF-α and IL-6), and NO in BALF. Pretreatment with LLF extract downregulated F4/80 expression in lung tissue and suppressed LPS-induced elevations in BALF and lung tissue levels of MPO. Moreover, treatment with LLF extract reduced the expression level of proteins associated with the MAPK signaling pathway (p-p38, p-JNK, p-ERK) and TLR4/NF-κB signaling pathways (TLR4, Myd88, p-IκB, p-p65). Moreover, LLF extract upregulated Nrf2, HO-1 and NQO1 protein levels, downregulated Keap1 protein level. Immunohistochemical analysis revealed that LLF reduced the LPS-induced increase in Nfr2 expression in lung tissues.Ethanol extracts of LLF ameliorated LPS-induced acute lung injury by suppressing inflammatory response and enhancing antioxidation capacity, which correlated with the MAPK/NF-κB and Nfr2/HO-1 signaling pathways.
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- 2022
24. PGC-1
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Lei, Chen, Yuan, Qin, Bilin, Liu, Meng, Gao, Anqi, Li, Xue, Li, and Guohua, Gong
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Mitochondria with structural and functional integrity are essential for maintaining mitochondrial function and cardiac homeostasis. It is involved in the pathogenesis of many diseases. Peroxisome proliferator-activated receptor
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- 2022
25. Mitochondrial fusion mediated by fusion promotion and fission inhibition directs adult mouse heart function toward a different direction
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Meng Gao, Bilin Liu, Guohua Gong, Anqi Li, Yuan Qin, Xiangang Tian, and Wenting Jiang
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Dynamins ,0301 basic medicine ,MFN2 ,Mice, Transgenic ,Mitochondrial Dynamics ,Biochemistry ,Mitochondria, Heart ,Cell Line ,03 medical and health sciences ,chemistry.chemical_compound ,Mitofusin-2 ,0302 clinical medicine ,Downregulation and upregulation ,Mitophagy ,Genetics ,Animals ,Myocytes, Cardiac ,Mitochondrial calcium uptake ,Molecular Biology ,Superoxide ,Fibroblasts ,Cell biology ,030104 developmental biology ,mitochondrial fusion ,Mitochondrial biogenesis ,chemistry ,Reactive Oxygen Species ,030217 neurology & neurosurgery ,Biotechnology - Abstract
Mitochondrial fusion and fission are essential for heart function. Abrogating mitochondrial dynamism leads to cardiomyopathy. Excessive mitochondrial fragmentation is involved in most heart diseases, thus enhancing mitochondrial fusion will be a potential therapeutic strategy. To understand the effects of promoting mitochondrial fusion in adult cardiac, we investigated mice hearts, and cultured murine embryonic fibroblasts (MEFs), in which mitofusin 2 (Mfn2) overexpressed or dynamin-related protein 1 (Drp1) was abrogated concomitantly forcing mitochondrial fusion. Parallel studies revealed that fission-defective Drp1 knockout hearts and MEFs evoked stronger mitochondrial enlargement, enhanced mitophagy with mitochondrial volume decrease and increased mitochondrial calcium uptake, superoxide production, and permeability transition pore opening, contributed to cardiomyocyte apoptosis and dilated cardiomyopathy. Mfn2 overexpression in the adult heart is comparable with the control except for slight mitochondrial enlargement and mitochondrial volume increase, but without mitophagy induction. Moreover, Mfn2 overexpression increases mitochondrial biogenesis and fusion could protect against mitochondrial fragmentation and Drp1 deletion evoking mitophagy in MEFs. Our findings indicate that mitochondrial fusion provoked by fusion promotion and fission inhibition direct the different fate of heart, Mfn2 upregulation other than Drp1 downregulation well maintains heart mitochondrial function is a more safe strategy for correcting excessive mitochondrial fragmentation in hearts.
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- 2019
26. Protective effect of pteryxin on LPS-induced acute lung injury via modulating MAPK/NF-κB pathway and NLRP3 inflammasome activation
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Tian-qi Xuan, Guohua Gong, Huanhuan Du, Chunyan Liu, Yun Wu, Guilan Bao, Qianqian Ma, and Dong Zhen
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Pharmacology ,Inflammation ,Lipopolysaccharides ,Male ,Mice, Inbred BALB C ,Dose-Response Relationship, Drug ,Inflammasomes ,MAP Kinase Signaling System ,Acute Lung Injury ,NF-kappa B ,Molecular Docking Simulation ,Mice ,Coumarins ,Drug Discovery ,NLR Family, Pyrin Domain-Containing 3 Protein ,Animals ,Cytokines - Abstract
Peucedanum praeruptorum seed root is a common medicinal herb with antipyretic, expectorant, antitussive, and therapeutic effects against bronchitis and furuncle. The roots of this herb contain many coumarin compounds, including pteryxin.To investigate whether pteryxin can alleviate the LPS-induced lung injury and the mechanism involved.Male BALB/C mice were orally given sodium carboxymethylcellulose (CMC-Na) (0.5%, 1mL/100g) and pteryxin (suspended in CMC-Na; 0.5%) at 5, 10, 25 mg/kg once daily for 7 days. Subsequently, the mice received a single intratracheal instillation of 5 mg/kg LPS or saline as the control. After 8 hours, the mice were sacrificed to collect bronchoalveolar lavage fluid (BALF) and lung tissues. These samples were used to determine the lung W/D (wet/dry) weight ratio, total protein (TP) levels, inflammatory cytokines (IL-6, TNF-α, and IL-1β) and expression of protein involved in MAPK/NF-κB pathway and NLRP3 inflammasome. HE staining was carried out on tissue sections to explore the pathological alterations induced by LPS. The protein expression of F4/80 and NLRP3 in lung tissues was analyzed using immunohistochemical staining. The binding of pteryxin to target proteins (MAPK, NF-κB and NLRP3) was determined based on molecular docking tests.Treatment with pteryxin reduced the lung W/D weight ratio, total protein (TP) level and levels of inflammatory cytokines (TNFα, IL-6 and IL-1 β) significantly. Therefore, it ameliorated LPS-induced inflammatory response in BALB/C mice. Moreover, pteryxin suppressed LPS-induced upregulation of proteins involved in MAPK/NF-κB signaling pathway and NLRP3 inflammasome activation. The expression level of F4/80 and NLRP3 was also downregulated by pteryxin pretreatment in lung tissues. Docking analysis revealed that pteryxin bound to target proteins (MAPK, NF- κB and NLRP3) with a fit-well pattern .Pteryxin may attenuate LPS-induced acute lung injury by dampening MAPK/NF-κB signaling and NLRP 3 inflammasome activation.
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- 2021
27. Design, Synthesis, and
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Ming, Bian, Guohua, Gong, Pang, Lei, Huanhuan, Du, Chunmei, Bai, Chengxi, Wei, Zheshan, Quan, and Qianqian, Ma
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Inflammation ,Limonins ,Lipopolysaccharides ,Mice ,RAW 264.7 Cells ,Anti-Inflammatory Agents ,NF-kappa B ,Animals ,Cytokines - Abstract
In this study, limonin derivatives were used to design new anti-inflammatory compounds with high pharmacological activity and low toxicity. A total of 23 new limonin derivatives were discovered, synthesized, and screened for their anti-inflammatory activity against lipopolysaccharide (LPS)-treated RAW 264.7 cells. Of them, compound
- Published
- 2021
28. Synergistic anti-inflammatory effects of peimine, peiminine, and forsythoside a combination on LPS-induced acute lung injury by inhibition of the IL-17-NF-κB/MAPK pathway activation
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Chunyan, Liu, Dong, Zhen, Huanhuan, Du, Guohua, Gong, Yun, Wu, Qianqian, Ma, and Zhe-Shan, Quan
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Lipopolysaccharides ,Male ,Pharmacology ,Interleukin-6 ,Tumor Necrosis Factor-alpha ,Acute Lung Injury ,Interleukin-17 ,Anti-Inflammatory Agents ,NF-kappa B ,Toll-Like Receptor 4 ,Mice ,Fritillaria ,Drug Discovery ,Animals ,Cytokines ,Glycosides ,Forsythia ,Lung ,Cevanes - Abstract
Forsythia suspensa (Thunb.) Vahl and Fritillaria thunbergii Miq are traditional Chinese medicines that exhibit the ability to clear heat and toxic material effects. In China, the combination of these two medicines is widely used to treat mucopurulent sputum and bloody phlegm, arising due to phlegm-heat obstruction in respiratory diseases. However, very limited information is available regarding the combined anti-inflammatory effect of important effective components of Forsythia suspensa (Thunb.) Vahl and Fritillaria thunbergii Miq, namely peimine, peiminine, and forsythoside A.To investigate synergistic anti-inflammatory effects of combined administration of peimine, peiminine, and forsythoside A on LPS-induced acute lung injury compared to combined administration of two compounds or individual administration, and unravel the underlying mechanism.In the present study, male BALB/c mice received an oral dosage of sodium carboxymethylcellulose (CMC-Na) (0.5%, 1 mL/100 g), peimine, peiminine, forsythoside A, peimine + forsythoside A, peiminine + forsythoside A, and peimine + peiminine + forsythoside A (suspended in CMC-Na; 0.5%), once daily for 7 days. Subsequently, intratracheal instillation of LPS was applied to establish acute lung injury model. After 6 h of administration, the mice were sacrificed, and bronchoalveolar lavage fluid (BALF) and lung tissues were collected. These samples were further used to determine lung W/D (wet/dry) weight ratio, total protein (TP) levels, inflammatory cytokines (IL-6, TNF-α, IL-1β, and IL-17), and expression of proteins involved in TLR4/MAPK/NF-κB pathway and IL-17 pathway. Further, tissue sections were subjected to HE staining to assess the pathological alterations induced by LPS. The expression of IL-6 and TNF-α proteins in lung tissues was also analyzed using immunohistochemical staining.A synergistic anti-inflammatory effect of peimine, peiminine, and forsythoside A was observed when administered in combination to LPS-induced acute lung injury. The combined administration of peimine, peiminine, and forsythoside A had a strongly inhibitory effects on the W/D weight ratio, total protein (TP) level and the inflammatory cytokines (TNF-α, IL-6, IL-1β, and IL-17) level in acute lung injury mice, compared to combined administration of two compounds or individual administration. The infiltration of inflammatory cells and thickened bronchoalveolar walls induced by LPS were also ameliorated through the combined administration of peimine, peiminine, and forsythoside A. More importantly, the upregulation of protein related to TLR4/MAPK/NF-κB signaling pathway and the activation of IL-17 were significantly suppressed by pretreatment with each of the three compounds alone, while the effects of individual compounds were synergistically augmented by the combined pretreatment of these three compounds.The combined administration of peimine, peiminine, and forsythoside A ameliorated inflammatory response in acute lung injury mice induced by LPS in a synergistic manner, the mechanism may be related to the dampening of the TLR4/MAPK/NF-κB signaling pathway and IL-17 activation.
- Published
- 2022
29. Calibration and measurement of mitochondrial pH in intact adult rat cardiomyocytes
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Ying Zhang, Anqi Li, Hanyu Liu, Bilin Liu, Lei Chen, Meng Gao, Guohua Gong, Yuan Qin, and Yufei Gao
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Science (General) ,Cytological Techniques ,Naphthols ,General Biochemistry, Genetics and Molecular Biology ,law.invention ,Q1-390 ,Adherent cell ,Confocal microscopy ,law ,Protocol ,Animals ,Benzopyrans ,Myocytes, Cardiac ,Fluorescent Dyes ,Membrane potential ,Microscopy ,General Immunology and Microbiology ,Chemistry ,Rhodamines ,General Neuroscience ,Metabolism ,Cell Biology ,Hydrogen-Ion Concentration ,Cell biology ,Mitochondria ,Rats ,Molecular/Chemical Probes ,Function (biology) - Abstract
Summary Mitochondrial pH is a vital parameter of the mitochondrial environment, which determines the rate of many mitochondrial functions, including metabolism, membrane potential, fate, etc. Abnormal mitochondrial pH is always closely related to the health status of cells. Analyzing mitochondrial pH can serve as a proxy for mitochondrial and cellular function. This protocol describes the use of SNARF-1 AM, a pH-sensitive fluorophore, to measure mitochondrial pH. This protocol details the steps to evaluate mitochondrial pH in live adult cardiomyocytes using confocal microscopy. The protocol can be adapted to other adherent cell types. For complete details on the use and execution of this protocol, please refer to Wei-LaPierre et al. (2013)., Graphical abstract, Highlights • SNARF-1 AM is a pH-sensitive fluorophore for measuring mitochondrial pH • Mitochondrial pH measurements in live cells with confocal microscopy • This protocol uses live cardiomyocytes but can be easily adapted to other adherent cells, Mitochondrial pH is a vital parameter of the mitochondrial environment, which determines the rate of many mitochondrial functions, including metabolism, membrane potential, fate, etc. Abnormal mitochondrial pH is always closely related to the health status of cells. Analyzing mitochondrial pH can serve as a proxy for mitochondrial and cellular function. This protocol describes the use of SNARF-1 AM, a pH-sensitive fluorophore, to measure mitochondrial pH. This protocol details the steps to evaluate mitochondrial pH in live adult cardiomyocytes using confocal microscopy. The protocol can be adapted to other adherent cell types.
- Published
- 2021
30. The Combination of Paraformaldehyde and Glutaraldehyde Is a Potential Fixative for Mitochondria
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Guohua Gong, Wenting Jiang, Yuan Qin, Hanyu Liu, Yufei Gao, Xiangang Tian, Meng Gao, and Anqi Li
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0301 basic medicine ,Polymers ,Mitochondrion ,Biochemistry ,Microbiology ,Article ,mitochondrial morphology ,03 medical and health sciences ,chemistry.chemical_compound ,Fixatives ,Mice ,0302 clinical medicine ,Formaldehyde ,Animals ,Paraformaldehyde ,Molecular Biology ,Fixative ,Microscopy, Confocal ,Superoxide ,QR1-502 ,Cell biology ,mitochondria ,030104 developmental biology ,chemistry ,fixative ,Apoptosis ,Glutaral ,glutaraldehyde ,Glutaraldehyde ,030217 neurology & neurosurgery ,Immunostaining ,Abnormal mitochondrial morphology ,paraformaldehyde - Abstract
Mitochondria are highly dynamic organelles, constantly undergoing shape changes, which are controlled by mitochondrial movement, fusion, and fission. Mitochondria play a pivotal role in various cellular processes under physiological and pathological conditions, including metabolism, superoxide generation, calcium homeostasis, and apoptosis. Abnormal mitochondrial morphology and mitochondrial protein expression are always closely related to the health status of cells. Analysis of mitochondrial morphology and mitochondrial protein expression in situ is widely used to reflect the abnormality of cell function in the chemical fixed sample. Paraformaldehyde (PFA), the most commonly used fixative in cellular immunostaining, still has disadvantages, including loss of antigenicity and disruption of morphology during fixation. We tested the effect of ethanol (ETHO), PFA, and glutaraldehyde (GA) fixation on cellular mitochondria. The results showed that 3% PFA and 1.5% GA (PFA-GA) combination reserved mitochondrial morphology better than them alone in situ in cells. Mitochondrial network and protein antigenicity were well maintained, indicated by preserved MitoTracker and mitochondrial immunostaining after PFA-GA fixation. Our results suggest that the PFA-GA combination is a valuable fixative for the study of mitochondria in situ.
- Published
- 2021
31. Extracellular vesicles derived from human bone marrow mesenchymal stem cells protect rats against acute myocardial infarction-induced heart failure
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Liying Xuan, Danni Fu, Dong Zhen, Chengxi Wei, Dongsong Bai, Lijun Yu, and Guohua Gong
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Heart Failure ,Extracellular Vesicles ,Histology ,Human Umbilical Vein Endothelial Cells ,Myocardial Infarction ,Animals ,Humans ,Bone Marrow Cells ,Mesenchymal Stem Cells ,Cell Biology ,Fibrosis ,Pathology and Forensic Medicine ,Rats - Abstract
Extracellular vesicles (EVs) derived from human bone marrow mesenchymal stem cells (BMSCs) are suggested to promote angiogenesis in a rat model of acute myocardial infarction (AMI). This study aimed to explore the underlying mechanism of BMSCs-EVs in AMI-induced heart failure (HF). BMSCs were isolated and verified, and EVs were purified and identified. After establishment of AMI-induced HF models, rats were treated with BMSCs-EVs and/or overexpressing (ov)/knocking down (kd) bone morphogenetic protein 2 (BMP2). Cardiac function, myocardial histopathological changes, angiogenesis, and vascular regeneration density were measured. Levels of pro-angiogenesis factors and cardiomyocyte apoptosis were detected. The viability and angiogenesis of hypoxic human umbilical vein endothelial cells (HUVECs) were measured. After BMSCs-EV treatment, the cardiac function of HF rats was improved, myocardial fibrosis and inflammatory cell infiltration were decreased, angiogenesis was increased, and cardiomyocyte apoptosis was inhibited. BMP2 was significantly upregulated in the myocardium. Ov-BMP2-BMSCs-EVs alleviated myocardial fibrosis and inflammatory cell infiltration, and promoted angiogenesis of HF rats, and improved the activity and angiogenesis of hypoxic HUVECs, while kd-BMP2-BMSCs-EVs showed limited protection against AMI-induced HF. BMSCs-EVs deliver BMP2 to promote angiogenesis and improve cardiac function of HF rats.
- Published
- 2021
32. Modified Protocol for A Mouse Heart Failure Model Using Minimally Invasive Transverse Aortic Constriction
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Yuan Qin, Anqi Li, Guohua Gong, Meng Gao, and Bilin Liu
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Artificial ventilation ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,General Biochemistry, Genetics and Molecular Biology ,Model Organisms ,Internal medicine ,Protocol ,Medicine ,Animals ,Minimally Invasive Surgical Procedures ,lcsh:Science (General) ,Survival rate ,Mouse Heart ,Aorta ,Heart Failure ,Rib cage ,General Immunology and Microbiology ,business.industry ,General Neuroscience ,Aortic constriction ,Tracheal intubation ,Ultrasonography, Doppler ,Cell Biology ,Constriction ,Mice, Inbred C57BL ,Disease Models, Animal ,Cardiology ,business ,lcsh:Q1-390 - Abstract
Summary Here, we present a modified protocol for a mouse heart failure (HF) model using minimally invasive transverse aortic constriction (miTAC). miTAC is a more effective method in mice than the standard open-chest transverse aortic constriction (TAC) to generate an HF model. miTAC does not require the cutting of the ribs or tracheal intubation with artificial ventilation; it also has a higher survival rate. The successful outcome of the HF model can be verified using transthoracic echocardiography and histology. For complete details on the use and execution of this protocol, please refer to Hu et al. (2003) and Richards et al. (2019)., Graphical Abstract, Highlights • miTAC is an effective method to generate a mouse heart failure model • miTAC does not need tracheal intubation with artificial ventilation • The survival rate of miTAC is higher than that of open-chest TAC, Here, we present a modified protocol for a mouse heart failure (HF) model using minimally invasive transverse aortic constriction (miTAC). miTAC is a more effective method in mice than the standard open-chest transverse aortic constriction (TAC) to generate an HF model. miTAC does not require the cutting of the ribs or tracheal intubation with artificial ventilation; it also has a higher survival rate. The successful outcome of the HF model can be verified using transthoracic echocardiography and histology.
- Published
- 2020
33. Protocol for Isolation of Viable Adult Rat Cardiomyocytes with High Yield
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Anqi Li, Xiangang Tian, Meng Gao, Yuan Qin, Guohua Gong, Bilin Liu, and Wenting Jiang
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General Immunology and Microbiology ,Enzymatic digestion ,General Neuroscience ,Cell Culture Techniques ,Cell Separation ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Cell biology ,Rats ,Protocol ,Animals ,Myocytes, Cardiac ,lcsh:Science (General) ,Drug toxicity ,Cells, Cultured ,lcsh:Q1-390 - Abstract
Summary Isolation of high-quantity and high-quality ventricular cardiomyocytes from adult rats is critical to study heart physiology and pathology and for drug toxicity screening. It remains challenging to produce a high yield of viable cardiomyocytes from rats. Here, we present our modified enzymatic digestion protocol that relies on the Langendorff device to generate large numbers of viable cardiomyocytes consistently. The most critical parts of this protocol are the selection of rat age and digestion time to obtain viable cardiomyocytes. For complete details on the use and execution of this protocol, please refer to Liu et al. (2019) and Qin et al. (2020)., Graphical Abstract, Highlights • The age of the rat is critical for the perfusion digest to obtain viable cardiomyocytes • Blebbistatin is vital for the isolation and culture of adult cardiomyocytes • Protease treatment increases the yield of cardiomyocyte • Dead cells and other cell types are separated by gravity, Isolation of high-quantity and high-quality ventricular cardiomyocytes from adult rats is critical to study heart physiology and pathology and for drug toxicity screening. It remains challenging to produce a high yield of viable cardiomyocytes from rats. Here, we present our modified enzymatic digestion protocol that relies on the Langendorff device to generate large numbers of viable cardiomyocytes consistently. The most critical parts of this protocol are the selection of rat age and digestion time to obtain viable cardiomyocytes.
- Published
- 2020
34. Mitoflash generated at the Qo site of mitochondrial Complex III
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Yuan Qin, Xiangang Tian, Sailei Wei, Guohua Gong, Bilin Liu, Anqi Li, and Meng Gao
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0301 basic medicine ,Yellow fluorescent protein ,Aging ,Cell Membrane Permeability ,Physiology ,Clinical Biochemistry ,Succinic Acid ,Antimycin A ,Antioxidants ,Electron Transport ,Electron Transport Complex IV ,Rats, Sprague-Dawley ,03 medical and health sciences ,chemistry.chemical_compound ,Electron Transport Complex III ,Mice ,0302 clinical medicine ,Adenosine Triphosphate ,Superoxides ,Animals ,Myocytes, Cardiac ,Sodium cyanide ,biology ,Myxothiazol ,Stigmatellin ,Superoxide ,Cell Biology ,Electron transport chain ,Mitochondria ,030104 developmental biology ,chemistry ,030220 oncology & carcinogenesis ,Coenzyme Q – cytochrome c reductase ,biology.protein ,Biophysics ,Tetradecanoylphorbol Acetate - Abstract
The previous research has shown that mitochondrial flash (mitoflash) genesis are functionally and mechanistically integrated with mitochondrial electron transport chain (ETC) energy metabolism. However, the response of mitoflash to superoxide is not entirely consistent with the response of MitoSOX Red. The generation mechanism of mitoflash is still unclear. Here, we investigated mitoflash activities, using the different combinations of ETC substrates and inhibitors, in permeabilized cardiomyocytes or hearts. We found that blocking the complete electron flow, from Complex I to IV, with any one of ETC inhibitors including rotenone (Rot), antimycin A (AntA), myxothiazol (Myxo), stigmatellin, and sodium cyanide, will lead to the abolishment of mitoflashes triggered by substrates in adult permeabilized cardiomyocytes. However, Myxo boosted mitoflashes triggered by the reverse electron of N,N,N',N'-tetramethyl-p-phenylenediamine/ascorbate. Moreover, Rot and AntA furtherly enhanced mitoflash activity rather than depressed it, suggesting that mitoflashes generated at the Complex III Qo site. Meanwhile, the inhibition of Complex III protein expression resulted in the activity of Complex III decrease, which decreased mitoflash frequency. The function defect (no change of protein level) of the Qo site of Complex III in aging hearts augmented mitoflash generation confirmed the Qo site function was critical to mitoflash genesis. Thus, our results indicate that mitoflash detected by circularly permuted yellow fluorescent protein is generated at the Qo site of Complex III.
- Published
- 2020
35. Heart specific knockout of Ndufs4 ameliorates ischemia reperfusion injury
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Zhen Zhang, Stephen C. Kolwicz, Wang Wang, Guohua Gong, Rong Tian, Pei Wang, Huiliang Zhang, and Peter S. Rabinovitch
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0301 basic medicine ,medicine.medical_specialty ,Biopsy ,Cell Respiration ,Ischemia ,Fluorescent Antibody Technique ,Mice, Transgenic ,Myocardial Reperfusion Injury ,Mitochondrion ,medicine.disease_cause ,Models, Biological ,Article ,Mitochondria, Heart ,Mice ,03 medical and health sciences ,Internal medicine ,Genetic model ,medicine ,Animals ,Genetic Predisposition to Disease ,Myocytes, Cardiac ,Molecular Biology ,Heart metabolism ,Mice, Knockout ,Electron Transport Complex I ,Cell Death ,Chemistry ,Myocardium ,NDUFS4 ,medicine.disease ,Reverse electron flow ,Disease Models, Animal ,Oxidative Stress ,030104 developmental biology ,Endocrinology ,Organ Specificity ,Reactive Oxygen Species ,Cardiology and Cardiovascular Medicine ,Reperfusion injury ,Biomarkers ,Oxidative stress - Abstract
Rationale Ischemic heart disease (IHD) is a leading cause of mortality. The most effective intervention for IHD is reperfusion, which ironically causes ischemia reperfusion (I/R) injury mainly due to oxidative stress-induced cardiomyocyte death. The exact mechanism and site of reactive oxygen species (ROS) generation during I/R injury remain elusive. Objective We aim to test the hypothesis that Complex I-mediated forward and reverse electron flows are the major source of ROS in I/R injury of the heart. Methods and results We used a genetic model of mitochondrial Complex I deficiency, in which a Complex I assembling subunit, Ndufs4 was knocked out in the heart (Ndufs4H−/−). The Langendorff perfused Ndufs4H−/− hearts exhibited significantly reduced infarct size (45.3 ± 5.5% in wild type vs 20.9 ± 8.1% in Ndufs4H−/−), recovered contractile function, and maintained mitochondrial membrane potential after no flow ischemia and subsequent reperfusion. In cultured adult cardiomyocytes from Ndufs4H−/− mice, I/R mimetic treatments caused minimal cell death. Reintroducing Ndufs4 in Ndufs4H−/− cardiomyocytes abolished the protection. Mitochondrial NADH declined much slower in Ndufs4H−/− cardiomyocytes during reperfusion suggesting decreased forward electron flow. Mitochondrial flashes, a marker for mitochondrial respiration, were inhibited in Ndufs4H−/− cardiomyocytes at baseline and during I/R, which was accompanied by preserved aconitase activity suggesting lack of oxidative damage. Finally, pharmacological blockade of forward and reverse electron flow at Complex I inhibited I/R-induced cell death. Conclusions These results provide the first genetic evidence supporting the central role of mitochondrial Complex I in I/R injury of mouse heart. The study also suggests that both forward and reverse electron flows underlie oxidative cardiomyocyte death during reperfusion.
- Published
- 2018
36. Maternal iron deficiency does not affect the iron status of fetuses with congenital heart defects: Does it affect heart development?
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Wenting Jiang, Yuan Qin, Bili Liu, Wanqiang Xue, Meng Gao, Anqi Li, and Guohua Gong
- Subjects
Heart Defects, Congenital ,Fetus ,Heart development ,Anemia, Iron-Deficiency ,business.industry ,Iron ,Physiology ,Iron deficiency ,medicine.disease ,Affect (psychology) ,Pregnancy ,Case-Control Studies ,medicine ,Humans ,Female ,Iron status ,Cardiology and Cardiovascular Medicine ,business - Published
- 2019
37. 1, 8-cineole protects against ISO-induced heart failure by inhibiting oxidative stress and ER stress in vitro and in vivo
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Chengxi Wei, Yu Chen, Xuan Zhang, Dan-ni Fu, Guohua Gong, Dong Zhen, Yao Fu, An Xing, and Yu Wang
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Apoptosis ,CHOP ,Protective Agents ,medicine.disease_cause ,Cell Line ,medicine ,Animals ,Humans ,Myocytes, Cardiac ,Heart Failure ,Pharmacology ,Cardioprotection ,chemistry.chemical_classification ,Reactive oxygen species ,Eucalyptol ,Kinase ,Chemistry ,Isoproterenol ,Endoplasmic Reticulum Stress ,Rats ,Cell biology ,Disease Models, Animal ,Oxidative Stress ,Unfolded protein response ,Signal transduction ,Oxidative stress ,Signal Transduction - Abstract
Sugemule-3 is widely adopted in clinical practice to manage cardio-cerebral diseases. 1, 8-cineole is the main ingredient of Sugemule-3, however, the underlying cellular mechanisms for its protective effect are poorly understood. 1, 8-cineole improved the survival of H9C2 cardiomyocytes during isoproterenol (ISO) injury and reduced ISO-induced apoptosis. Compared to the ISO group, 1, 8-cineole highly attenuated the generation of ISO-induced reactive oxygen species (ROS), the depolarization of △ψm, suppression of the Bax/Bcl-2 ratio, and p-caspase 3 expression, in vitro. Furthermore, 1, 8-cineole treatment in H9C2 cardiomyocytes lowered the expressions of 78-kDa glucose-regulated protein (GRP78), p-protein kinase-like ER kinase (PERK), activation of transcription factor (ATF) 4, and ER stress effector protein C/EBP and homologous protein (CHOP). These findings implied that 1, 8-cineole contribute to cardioprotection via the GRP78/CHOP pathways. Using animal models, 1, 8-cineole was revealed to markedly alleviate ISO-induced heart injury, and reduce cardiac hypertrophy, formation of the cytoplasmic vacuole, loss of myofiber, and fibrosis by inhibiting oxidative stress and ER stress. 1, 8-cineole reduces apoptosis by inhibiting signaling pathways related to oxidative stress and ER stress. These findings implicate 1, 8-cineole as a potential therapeutic target for cardiac hypertrophy-related heart diseases, including heart failure.
- Published
- 2021
38. Design, Synthesis, and In Vitro and In Vivo Biological Evaluation of Limonin Derivatives for Anti-Inflammation Therapy.
- Author
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Ming Bian, Guohua Gong, Pang Lei, Huanhuan Du, Chunmei Bai, Chengxi Wei, Zheshan Quan, and Qianqian Ma
- Published
- 2021
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39. Comparative study on isolation and mitochondrial function of adult mouse and rat cardiomyocytes
- Author
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Guohua Gong, Xiangang Tian, Anqi Li, Wenting Jiang, Meng Gao, Bilin Liu, and Yuan Qin
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0301 basic medicine ,Mitochondrial ROS ,Cell physiology ,Time Factors ,Cell Separation ,030204 cardiovascular system & hematology ,Mitochondrial Membrane Transport Proteins ,Mitochondria, Heart ,Rats, Sprague-Dawley ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Superoxides ,Respiration ,Myocyte ,Animals ,Myocytes, Cardiac ,Molecular Biology ,Cells, Cultured ,chemistry.chemical_classification ,Reactive oxygen species ,Superoxide ,Mitochondrial Permeability Transition Pore ,MPTP ,Age Factors ,Cell biology ,Mice, Inbred C57BL ,Perfusion ,030104 developmental biology ,chemistry ,Mitochondrial permeability transition pore ,Calcium ,Cardiology and Cardiovascular Medicine - Abstract
Background Cultured adult mouse and rat cardiomyocytes are the best and low-cost cell model for cardiac cellular physiology, pathology, drug toxicity screening, and intervention. The functions of mouse cardiomyocytes decline faster than rat cardiomyocytes in culture conditions. However, little is known about the difference of mitochondrial function between cultured mouse and rat myocytes. Methods and results A large number of adult mouse and rat cardiomyocytes were comparative isolated using a simple perfusion system. Cardiomyocytes mitochondrial functions were measured after 2 h, 1 day, 2 days, 3 days, and 4 days culture by monitoring mitoflashes. We found that the mitochondrial function of mouse myocytes was remarkedly declined on the third day. Then, we focused on the third day cultured mouse and rat myocytes, comparatively analyzing the respiration function and superoxide generation stimulated by pyruvate/malate/ADP and the mitochondrial permeability transition pore (mPTP) opening induction. Mouse myocytes showed lower respiration and mitoflash activity, but without the change of maximum uncoupled respiration when compared with rat myocytes. Although the response to superoxide production stimulated by respiration substrates was slower than rat myocytes, the basal superoxide generation is faster than the rat. The faster mitochondrial reactive oxygen species (ROS) generation of mouse myocytes upon laser stimulation triggered the faster mPTP opening compared with the rat. Finally, antioxidant MitoTEMPO pretreatment preserved the mitochondrial function of mouse myocytes on the third day. Conclusions The mitochondrial function and stability are different between cultured mouse and rat cardiac myocytes beyond 3 days even though they both belong to Muridae. Mitochondrial ROS impairs the mitochondrial functions of mouse cardiomyocytes on the third day. Suppressing superoxide maintained the mitochondrial function of mouse myocytes on the third day.
- Published
- 2019
40. Correcting mitochondrial fusion by manipulating mitofusin conformations
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Guohua Gong, Daria Mochly-Rosen, Nir Qvit, Ann Benz, Richard N. Kitsis, Sara K. Donnelly, Gerald W. Dorn, Evripidis Gavathiotis, Antonietta Franco, Steven Mennerick, Opher S. Kornfeld, Yun Chen, Julie Fleischer, Louis Hodgson, and Nikolaos Biris
- Subjects
Models, Molecular ,0301 basic medicine ,Protein Conformation ,MFN2 ,Mitochondrion ,Biology ,Mitochondrial Dynamics ,Article ,Permeability ,GTP Phosphohydrolases ,Mice ,03 medical and health sciences ,Mitofusin-2 ,0302 clinical medicine ,Charcot-Marie-Tooth Disease ,Organelle ,Animals ,Gene ,Cells, Cultured ,Neurons ,Multidisciplinary ,Fibroblasts ,Mitochondria ,Cell biology ,030104 developmental biology ,mitochondrial fusion ,Biochemistry ,Mitochondrial fission ,Peptides ,030217 neurology & neurosurgery ,Function (biology) - Abstract
Mitochondria are dynamic organelles that exchange contents and undergo remodelling during cyclic fusion and fission. Genetic mutations in MFN2 (the gene encoding mitofusin 2) interrupt mitochondrial fusion and cause the untreatable neurodegenerative condition Charcot-Marie-Tooth disease type 2A (CMT2A). It has not yet been possible to directly modulate mitochondrial fusion, in part because the structural basis of mitofusin function is not completely understood. Here we show that mitofusins adopt either a fusion-constrained or a fusion-permissive molecular conformation, directed by specific intramolecular binding interactions, and demonstrate that mitofusin-dependent mitochondrial fusion can be regulated in mouse cells by targeting these conformational transitions. On the basis of this model, we engineered a cell-permeant minipeptide to destabilize the fusion-constrained conformation of mitofusin and promote the fusion-permissive conformation, reversing mitochondrial abnormalities in cultured fibroblasts and neurons that harbour CMT2A-associated genetic defects. The relationship between the conformational plasticity of mitofusin 2 and mitochondrial dynamism reveals a central mechanism that regulates mitochondrial fusion, the manipulation of which can correct mitochondrial pathology triggered by defective or imbalanced mitochondrial dynamics.
- Published
- 2016
41. Mitochondrial Flash: Integrative Reactive Oxygen Species and pH Signals in Cell and Organelle Biology
- Author
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Robert T. Dirksen, Wang Wang, Heping Cheng, Shey-Shing Sheu, Xianhua Wang, Lan Wei-LaPierre, and Guohua Gong
- Subjects
0301 basic medicine ,genetic structures ,Physiology ,Clinical Biochemistry ,Biosensing Techniques ,Oxidative phosphorylation ,Mitochondrion ,Biochemistry ,Antioxidants ,Oxidative Phosphorylation ,Cell Physiological Phenomena ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Superoxides ,Organelle ,Animals ,Humans ,Molecular Biology ,Caenorhabditis elegans ,General Environmental Science ,biology ,Superoxide ,Cell Biology ,Hydrogen-Ion Concentration ,Forum Review Articles ,biology.organism_classification ,Mitochondria ,Cell biology ,Luminescent Proteins ,030104 developmental biology ,chemistry ,mitochondrial fusion ,General Earth and Planetary Sciences ,Signal transduction ,Reactive Oxygen Species ,Oxidation-Reduction ,Biomarkers ,030217 neurology & neurosurgery ,Function (biology) ,Signal Transduction - Abstract
Significance: Recent breakthroughs in mitochondrial research have advanced, reshaped, and revolutionized our view of the role of mitochondria in health and disease. These discoveries include the development of novel tools to probe mitochondrial biology, the molecular identification of mitochondrial functional proteins, and the emergence of new concepts and mechanisms in mitochondrial function regulation. The discovery of “mitochondrial flash” activity has provided unique insights not only into real-time visualization of individual mitochondrial redox and pH dynamics in live cells but has also advanced understanding of the excitability, autonomy, and integration of mitochondrial function in vivo. Recent Advances: The mitochondrial flash is a transient and stochastic event confined within an individual mitochondrion and is observed in a wide range of organisms from plants to Caenorhabditis elegans to mammals. As flash events involve multiple transient concurrent changes within the mitochondrion (e.g., superoxide, pH, and membrane potential), a number of different mitochondrial targeted fluorescent indicators can detect flash activity. Accumulating evidence indicates that flash events reflect integrated snapshots of an intermittent mitochondrial process arising from mitochondrial respiration chain activity associated with the transient opening of the mitochondrial permeability transition pore. Critical Issues: We review the history of flash discovery, summarize current understanding of flash biology, highlight controversies regarding the relative roles of superoxide and pH signals during a flash event, and bring forth the integration of both signals in flash genesis. Future Directions: Investigations using flash as a biomarker and establishing its role in cell signaling pathway will move the field forward. Antioxid. Redox Signal. 25, 534–549.
- Published
- 2016
42. Protocol for Measurement of Oxygen Consumption Rate In Situ in Permeabilized Cardiomyocytes
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Yuan Qin, Guohua Gong, Anqi Li, Bilin Liu, and Meng Gao
- Subjects
Isolated mitochondria ,In situ ,Cell Membrane Permeability ,General Immunology and Microbiology ,Chemistry ,General Neuroscience ,Cytological Techniques ,chemistry.chemical_element ,Mitochondrion ,Oxygen ,Mitochondrial respiration ,General Biochemistry, Genetics and Molecular Biology ,Cell biology ,Oxygen Consumption ,Respiration ,Protocol ,Animals ,Myocytes, Cardiac ,lcsh:Science (General) ,lcsh:Q1-390 - Abstract
Summary Analysis of mitochondrial respiration function represented by the oxygen consumption rate is necessary for assessing mitochondrial respiration function. This protocol describes steps to evaluate the respiration function of mitochondria in situ in saponin-permeabilized cardiomyocytes. In permeabilized cells, mitochondria are in a relatively integrated cellular system, and mitochondrial respiration is more physiologically relevant than isolated mitochondria. For complete details on the use and execution of this protocol, please refer to Gong et al. (2015a) and Gong et al. (2015b)., Graphical Abstract, Highlights • Mitochondria are retained in a relatively integrated cellular system • Mitochondrial respiration in situ is more physiologically relevant • Saponin concentration is critical for mitochondrial integrity, Analysis of mitochondrial respiration function represented by the oxygen consumption rate is necessary for assessing mitochondrial respiration function. This protocol describes steps to evaluate the respiration function of mitochondria in situ in saponin-permeabilized cardiomyocytes. In permeabilized cells, mitochondria are in a relatively integrated cellular system, and mitochondrial respiration is more physiologically relevant than isolated mitochondria.
- Published
- 2020
43. Mitoflash lights single mitochondrial dynamics events in mature cardiomyocytes
- Author
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Guohua Gong, Meng Gao, Yuan Qin, Jia Sun, Anqi Li, and Bilin Liu
- Subjects
0301 basic medicine ,Contraction (grammar) ,Biophysics ,Mitochondrion ,Biochemistry ,Mitochondrial Dynamics ,Mitochondria, Heart ,Green fluorescent protein ,Rats, Sprague-Dawley ,03 medical and health sciences ,Organelle ,medicine ,Animals ,Myocytes, Cardiac ,Fibroblast ,Molecular Biology ,Cells, Cultured ,Microscopy, Confocal ,Chemistry ,Cell Biology ,Cell biology ,Luminescent Proteins ,030104 developmental biology ,medicine.anatomical_structure ,Mitochondrial matrix ,Mitochondrial fission ,Female - Abstract
Mitochondria, the powerhouse of eukaryotic cells, are highly dynamic organelle. Mitochondrial fission, fusion, kissing and contraction have been reported over and over again in non-static cells, such as fibroblast, with tubular mitochondrial networks. Even though the fluorescence propagation among mitochondria of mature cardiomyocytes had been captured using mitochondrial matrix targeted photoactivatable GFP (PAGFP) or MitoDendra proteins, there are no direct evidence that single real time mitochondrial dynamics events exist in mature cardiomyocytes with ball-like mitochondria. Here we first time revealed the visualizable single mitochondrial dynamics events in adult mature cardiomyocytes by the mitochondrial flash (mitoflash). We found fission, fusion, contraction and kissing were accompanied by a mitoflash event. Metabolism could increase mitochondrial contraction. Fusion and Kissing mediated inter-mitochondrial communication with higher frequency than fission. These results demonstrate that mitochondria of static mature cardiomyocytes are undergoing the rare, but real dynamics change.
- Published
- 2018
44. miR-539 acts as a tumor suppressor by targeting epidermal growth factor receptor in breast cancer
- Author
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Guohua Gong, Jilong Guo, and Bin Zhang
- Subjects
Adult ,Male ,0301 basic medicine ,lcsh:Medicine ,Down-Regulation ,Mice, Nude ,Breast Neoplasms ,Malignancy ,Article ,law.invention ,03 medical and health sciences ,Breast cancer ,Downregulation and upregulation ,Cell Movement ,law ,microRNA ,medicine ,Animals ,Humans ,Epidermal growth factor receptor ,lcsh:Science ,skin and connective tissue diseases ,Cell Proliferation ,Multidisciplinary ,biology ,Cell growth ,lcsh:R ,Middle Aged ,medicine.disease ,ErbB Receptors ,MicroRNAs ,030104 developmental biology ,Cell culture ,MCF-7 Cells ,Cancer research ,biology.protein ,Suppressor ,lcsh:Q ,Female - Abstract
Breast cancer is the most frequently diagnosed malignancy and the leading cause of cancer-associated death in women worldwide. microRNAs (miRNAs) play critical roles in the cellular processes of breast cancer. However, the crucial roles and underlying mechanisms of miR-539 in breast cancer remain unclear. By RT-qPCR, we found that expression of miR-539 was markedly down-regulated in breast cancer tissues and cell lines compared with that in paired adjacent normal tissues and normal cell lines. The low level of miR-539 expression was positively associated with lymph node metastasis. Furthermore, forced expression of miR-539 inhibited proliferation and migration of breast cancer MDA-MB-231 and MCF7 cells in vitro and suppressed tumor growth in vivo. Moreover, bioinformatics analysis and luciferase reporter assays indicated that epidermal growth factor receptor (EGFR) was a direct target of miR-539. Over-expression of miR-539 decreased the EGFR mRNA and protein levels in MDA-MB-231 and MCF7 cells. In addition, ectopic over-expression of EGFR partly reversed miR-539-inhibited proliferation as well as migration of MDA-MB-231 and MCF7 cells. Taken together, our results demonstrate that miR-539 functions as a tumor suppressor in breast cancer by downregulating EGFR, supporting the targeting of the novel miR-539/EGFR axis as a potentially effective therapeutic approach for breast cancer.
- Published
- 2018
45. Mitochondrial flash as a novel biomarker of mitochondrial respiration in the heart
- Author
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Guohua Gong, Xiaoyun Liu, Huiliang Zhang, Shey-Shing Sheu, and Wang Wang
- Subjects
genetic structures ,Physiology ,Cellular respiration ,Cell Respiration ,Mice, Transgenic ,Energetics and Metabolism ,Biology ,Mitochondrial apoptosis-induced channel ,Mitochondria, Heart ,Electron Transport ,Mice ,chemistry.chemical_compound ,Bacterial Proteins ,Superoxides ,Physiology (medical) ,Animals ,Myocyte ,Myocytes, Cardiac ,Cells, Cultured ,chemistry.chemical_classification ,Reactive oxygen species ,Electron Transport Complex I ,Microscopy, Confocal ,Superoxide ,Electron transport chain ,Rats ,Cell biology ,Luminescent Proteins ,Proton-Translocating ATPases ,chemistry ,Biomarker (medicine) ,sense organs ,Reactive Oxygen Species ,Cardiology and Cardiovascular Medicine ,Biomarkers - Abstract
Mitochondrial respiration through electron transport chain (ETC) activity generates ATP and reactive oxygen species in eukaryotic cells. The modulation of mitochondrial respiration in vivo or under physiological conditions remains elusive largely due to the lack of appropriate approach to monitor ETC activity in a real-time manner. Here, we show that ETC-coupled mitochondrial flash is a novel biomarker for monitoring mitochondrial respiration under pathophysiological conditions in cultured adult cardiac myocyte and perfused beating heart. Through real-time confocal imaging, we follow the frequency of a transient bursting fluorescent signal, named mitochondrial flash, from individual mitochondria within intact cells expressing a mitochondrial matrix-targeted probe, mt-cpYFP (mitochondrial-circularly permuted yellow fluorescent protein). This mt-cpYFP recorded mitochondrial flash has been shown to be composed of a major superoxide signal with a minor alkalization signal within the mitochondrial matrix. Through manipulating physiological substrates for mitochondrial respiration, we find a close coupling between flash frequency and the ETC electron flow, as measured by oxygen consumption rate in cardiac myocyte. Stimulating electron flow under physiological conditions increases flash frequency. On the other hand, partially block or slowdown electron flow by inhibiting the F0F1ATPase, which represents a pathological condition, transiently increases then decreases flash frequency. Limiting electron entrance at complex I by knocking out Ndufs4, an assembling subunit of complex I, suppresses mitochondrial flash activity. These results suggest that mitochondrial electron flow can be monitored by real-time imaging of mitochondrial flash. The mitochondrial flash frequency could be used as a novel biomarker for mitochondrial respiration under physiological and pathological conditions.
- Published
- 2015
46. Interdependence of Parkin-Mediated Mitophagy and Mitochondrial Fission in Adult Mouse Hearts
- Author
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Gerald W. Dorn, Yan Burelle, Guohua Gong, Scot J. Matkovich, Richard N. Kitsis, Moshi Song, and Åsa B. Gustafsson
- Subjects
Genetics ,Physiology ,Cardiac myocyte ,Cardiomyopathy ,Mitochondrion ,Biology ,medicine.disease ,Parkin ,nervous system diseases ,Cell biology ,Downregulation and upregulation ,Knockout mouse ,Mitophagy ,medicine ,Mitochondrial fission ,Cardiology and Cardiovascular Medicine - Abstract
Rationale: The role of Parkin in hearts is unclear. Germ-line Parkin knockout mice have normal hearts, but Parkin is protective in cardiac ischemia. Parkin-mediated mitophagy is reportedly either irrelevant, or a major factor, in the lethal cardiomyopathy evoked by cardiac myocyte–specific interruption of dynamin-related protein 1 (Drp1)-mediated mitochondrial fission. Objective: To understand the role of Parkin-mediated mitophagy in normal and mitochondrial fission–defective adult mouse hearts. Methods and Results: Parkin mRNA and protein were present at low levels in normal mouse hearts, but were upregulated after cardiac myocyte–directed Drp1 gene deletion in adult mice. Alone, forced cardiac myocyte Parkin overexpression activated mitophagy without adverse effects. Likewise, cardiac myocyte–specific Parkin deletion evoked no adult cardiac phenotype, revealing no essential function for, and tolerance of, Parkin-mediated mitophagy in normal hearts. Concomitant conditional Parkin deletion with Drp1 ablation in adult mouse hearts prevented Parkin upregulation in mitochondria of fission-defective hearts, also increasing 6-week survival, improving ventricular ejection performance, mitigating adverse cardiac remodeling, and decreasing cardiac myocyte necrosis and replacement fibrosis. Underlying the Parkin knockout rescue was suppression of Drp1-induced hyper-mitophagy, assessed as ubiquitination of mitochondrial proteins and mitochondrial association of autophagosomal p62/sequestosome 1 (SQSTM1) and processed microtubule-associated protein 1 light chain 3 (LC3-II). Consequently, mitochondrial content of Drp1-deficient hearts was preserved. Parkin deletion did not alter characteristic mitochondrial enlargement of Drp1-deficient cardiac myocytes. Conclusions: Parkin is rare in normal hearts and dispensable for constitutive mitophagic quality control. Ablating Drp1 in adult mouse cardiac myocytes not only interrupts mitochondrial fission, but also markedly upregulates Parkin, thus provoking mitophagic mitochondrial depletion that contributes to the lethal cardiomyopathy.
- Published
- 2015
47. Regulation of metabolism in individual mitochondria during excitation–contraction coupling
- Author
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Wang Wang, Guohua Gong, and Xiaoyun Liu
- Subjects
chemistry.chemical_element ,Mice, Transgenic ,Calcium ,Mitochondrion ,Biology ,Mitochondria, Heart ,Article ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,Bursting ,Animals ,Humans ,Myocyte ,Myocytes, Cardiac ,Mitochondrial calcium uptake ,Molecular Biology ,Cells, Cultured ,Excitation Contraction Coupling ,Heart Failure ,chemistry.chemical_classification ,Reactive oxygen species ,Superoxide ,Cell biology ,Coupling (electronics) ,HEK293 Cells ,chemistry ,Female ,Energy Metabolism ,Cardiology and Cardiovascular Medicine - Abstract
The heart is an excitable organ that undergoes spontaneous force generation and relaxation cycles driven by excitation–contraction (EC) coupling. A fraction of the oscillating cytosolic Ca 2 + during each heartbeat is taken up by mitochondria to stimulate mitochondrial metabolism, the major source of energy in the heart. Whether the mitochondrial metabolism is regulated individually during EC coupling and whether this heterogeneous regulation bears any physiological or pathological relevance have not been studied. Here, we developed a novel approach to determine the regulation of individual mitochondrial metabolism during cardiac EC coupling. Through monitoring superoxide flashes, which are stochastic and bursting superoxide production events arising from increased metabolism in individual mitochondria, we found that EC coupling stimulated the metabolism in individual mitochondria as indicated by significantly increased superoxide flash activity during electrical stimulation of the cultured intact myocytes or perfused heart. Mechanistically, cytosolic calcium transients promoted individual mitochondria to take up calcium via mitochondrial calcium uniporter, which subsequently triggered transient opening of the permeability transition pore and stimulated metabolism and bursting superoxide flash in that mitochondrion. The bursting superoxide, in turn, promoted local calcium release. In the early stage of heart failure, EC coupling regulation of superoxide flashes was compromised. This study highlights the heterogeneity in the regulation of cardiac mitochondrial metabolism, which may contribute to local redox signaling.
- Published
- 2014
48. Screening and identification of potential biomarkers in triple-negative breast cancer by integrated analysis
- Author
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Jilong Guo, Guohua Gong, and Bin Zhang
- Subjects
0301 basic medicine ,Oncology ,Cancer Research ,medicine.medical_specialty ,Triple Negative Breast Neoplasms ,Biology ,medicine.disease_cause ,Metastasis ,03 medical and health sciences ,Prostate cancer ,0302 clinical medicine ,Breast cancer ,Internal medicine ,medicine ,Biomarkers, Tumor ,Humans ,KEGG ,Triple-negative breast cancer ,Gene Expression Profiling ,Cancer ,General Medicine ,medicine.disease ,Microarray Analysis ,Prognosis ,Neoplasm Proteins ,Gene expression profiling ,Gene Expression Regulation, Neoplastic ,030104 developmental biology ,030220 oncology & carcinogenesis ,Female ,Carcinogenesis - Abstract
Triple-negative breast cancer (TNBC) has attracted great attention due to its unique biology, poor prognosis, and aggressiveness. TNBC patients are more likely to suffer from metastasis. We screened and identified the TNBC-specific genes as potential biomarkers. A total of 167 breast cancer samples (45 TNBC and 122 non-TNBC) were used in the integrated analysis. Gene expression microarrays were used to screen the differentially expressed genes. We identified 65 core DEGs. According to the GO and KEGG analysis, the gene function enrichment in TNBC was revealed, such as basal cell carcinoma, prostate cancer, oocyte meiosis and choline metabolism in cancer pathways. Moreover, the PPI network reconstruction would benefit the screening of hubs. A RFS analysis of TNBC-specific genes was also conducted. RT-PCR was used to validate the expression pattern of hubs in TNBC. Finally, nine genes were identified and all of them were novel, specific and higher dysregulation expressed genes in TNBC. Such that, these genes will serve as potential biomarkers in TNBC and benefit further research in TNBC.
- Published
- 2017
49. Mutation in the γ2-Subunit of AMP-Activated Protein Kinase Stimulates Cardiomyocyte Proliferation and Hypertrophy Independent of Glycogen Storage
- Author
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Wang Wang, Kei Sakamoto, Rong Tian, Jason Xu, Roger W. Hunter, Yu Ying Yang, Guohua Gong, Stephen C. Kolwicz, Lorena Garcia-Menendez, and Maengjo Kim
- Subjects
medicine.medical_specialty ,biology ,Glycogen ,Physiology ,Akt/PKB signaling pathway ,medicine.disease ,Cell biology ,chemistry.chemical_compound ,Endocrinology ,Glucose 6-phosphate ,chemistry ,AMP-activated protein kinase ,Internal medicine ,medicine ,biology.protein ,Glycogen storage disease ,Cardiology and Cardiovascular Medicine ,Protein kinase A ,Glycogen synthase ,GSK3B - Abstract
Rationale: AMP-activated protein kinase is a master regulator of cell metabolism and an attractive drug target for cancer and metabolic and cardiovascular diseases. Point mutations in the regulatory γ2-subunit of AMP-activated protein kinase (encoded by Prkag2 gene) caused a unique form of human cardiomyopathy characterized by cardiac hypertrophy, ventricular preexcitation, and glycogen storage. Understanding the disease mechanisms of Prkag2 cardiomyopathy is not only beneficial for the patients but also critical to the use of AMP-activated protein kinase as a drug target. Objective: We sought to identify the pro–growth-signaling pathway(s) triggered by Prkag2 mutation and to distinguish it from the secondary response to glycogen storage. Methods and Results: In a mouse model of N488I mutation of the Prkag2 gene (R2M), we rescued the glycogen storage phenotype by genetic inhibition of glucose-6-phosphate–stimulated glycogen synthase activity. Ablation of glycogen storage eliminated the ventricular preexcitation but did not affect the excessive cardiac growth in R2M mice. The progrowth effect in R2M hearts was mediated via increased insulin sensitivity and hyperactivity of Akt, resulting in activation of mammalian target of rapamycin and inactivation of forkhead box O transcription factor–signaling pathways. Consequently, cardiac myocyte proliferation during the postnatal period was enhanced in R2M hearts followed by hypertrophic growth in adult hearts. Inhibition of mammalian target of rapamycin activity by rapamycin or restoration of forkhead box O transcription factor activity by overexpressing forkhead box O transcription factor 1 rescued the abnormal cardiac growth. Conclusions: Our study reveals a novel mechanism for Prkag2 cardiomyopathy, independent of glycogen storage. The role of γ2-AMP-activated protein kinase in cell growth also has broad implications in cardiac development, growth, and regeneration.
- Published
- 2014
50. CaMKII induces permeability transition through Drp1 phosphorylation during chronic β-AR stimulation
- Author
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Rong Tian, Pei Wang, Wang Wang, Yisang Yoon, Huiliang Zhang, Shangcheng Xu, Nicolas Gutierrez Cortes, Weizhong Zhu, and Guohua Gong
- Subjects
0301 basic medicine ,Dynamins ,Male ,endocrine system ,animal diseases ,Science ,General Physics and Astronomy ,Stimulation ,Mice, Transgenic ,Mitochondrion ,environment and public health ,Mitochondrial Membrane Transport Proteins ,General Biochemistry, Genetics and Molecular Biology ,Article ,Cell Line ,Rats, Sprague-Dawley ,03 medical and health sciences ,Mitochondrial membrane transport protein ,chemistry.chemical_compound ,Ca2+/calmodulin-dependent protein kinase ,Receptors, Adrenergic, beta ,Animals ,Myocytes, Cardiac ,Phosphorylation ,Cells, Cultured ,Mice, Knockout ,Multidisciplinary ,biology ,Mitochondrial Permeability Transition Pore ,MPTP ,Isoproterenol ,General Chemistry ,Adrenergic beta-Agonists ,nervous system diseases ,Cell biology ,Mitochondria ,Mice, Inbred C57BL ,030104 developmental biology ,Mitochondrial permeability transition pore ,chemistry ,nervous system ,biology.protein ,cardiovascular system ,Mitochondrial fission ,Female ,Calcium-Calmodulin-Dependent Protein Kinase Type 2 - Abstract
Mitochondrial permeability transition pore (mPTP) is involved in cardiac dysfunction during chronic β-adrenergic receptor (β-AR) stimulation. The mechanism by which chronic β-AR stimulation leads to mPTP openings is elusive. Here, we show that chronic administration of isoproterenol (ISO) persistently increases the frequency of mPTP openings followed by mitochondrial damage and cardiac dysfunction. Mechanistically, this effect is mediated by phosphorylation of mitochondrial fission protein, dynamin-related protein 1 (Drp1), by Ca2+/calmodulin-dependent kinase II (CaMKII) at a serine 616 (S616) site. Mutating this phosphorylation site or inhibiting Drp1 activity blocks CaMKII- or ISO-induced mPTP opening and myocyte death in vitro and rescues heart hypertrophy in vivo. In human failing hearts, Drp1 phosphorylation at S616 is increased. These results uncover a pathway downstream of chronic β-AR stimulation that links CaMKII, Drp1 and mPTP to bridge cytosolic stress signal with mitochondrial dysfunction in the heart., β-adrenergic receptor signaling induces mitochondrial permeability transition pore (mPTP) opening. Here, Xu et al. show that this effect is mediated by phosphorylation of mitochondrial fission protein Drp1 by CamKII, which increases the frequency of transient mPTP opening.
- Published
- 2016
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