(-)-Epigallocatechin Gallate Promotes MicroRNA 145 Expression against Myocardial Hypoxic Injury through Dab2/Wnt3a/β-catenin

2020 ◽  
Vol 48 (02) ◽  
pp. 341-356
Author(s):  
Chiu-Mei Lin ◽  
Wei-Jen Fang ◽  
Bao-Wei Wang ◽  
Chun-Ming Pan ◽  
Su-Kiat Chua ◽  
...  

MicroRNA 145 (miR-145) is a critical modulator of cardiovascular diseases. The downregulation of myocardial miR-145 is followed by an increase in disabled-2 (Dab2) expression in cardiomyocytes. (-)-epigallocatechin gallate (EGCG) is a flavonoid that has been evaluated extensively due to its diverse pharmacological properties including anti-inflammatory effects. The aim of this study was to investigate the cardioprotective effects of EGCG under hypoxia-induced stress in vitro and in vivo. The hypoxic insult led to the suppression of miR-145 expression in cultured rat cardiomyocytes in a concentration-dependent manner. Western blotting and real-time PCR were performed. In rat myocardial infarction study, in situ hybridization, and immunofluorescent analyses were adopted. The western blot and real-time PCR data revealed that hypoxic stress with 2.5% O2 suppressed the expression of miR-145 and Wnt3a/[Formula: see text]-catenin in cultured rat cardiomyocytes but augmented Dab2. Treatment with EGCG attenuated Dab2 expression, but increased Wnt3a and [Formula: see text]-catenin in hypoxic cultured cardiomyocytes. Following in vivo myocardial infarction (MI) study, the data revealed the myocardial infarct area reduced by 48.5%, 44.6%, and 48.5% in EGCG (50[Formula: see text]mg/kg) or miR-145 dominant or Dab2 siRNA groups after myocardial infarction for 28 days, respectively. This study demonstrated that EGCG increased miR-145, Wnt3a, and [Formula: see text]-catenin expression but attenuated Dab2 expression. Moreover, EGCG ameliorated myocardial ischemia in vivo. The novel suppressive effect was mediated through the miR-145 and Dab2/Wnt3a/[Formula: see text]-catenin pathways.

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Na Li ◽  
Ming-Jie Wang ◽  
Sheng Jin ◽  
Ya-Dan Bai ◽  
Cui-Lan Hou ◽  
...  

Aims. To examine the expression patterns of hydrogen sulphide- (H2S-) producing enzymes in ischaemic heart tissue and plasma levels of H2S after 2 weeks of NaHS treatment after myocardial infarction (MI) and to clarify the role of endogenous H2S in the MI process.Results. After MI surgery, 2 weeks of treatment with the H2S donor NaHS alleviated ischaemic injury. Meanwhile, in ischemia myocardium, three H2S-producing enzymes, cystathionineγ-lyase (CSE), cystathionine-β-synthase (CBS), and 3-mercaptopyruvate sulfurtransferase (3-MST) significantly increased. Plasma H2S levels were also elevated.In vitro, NaHS treatment protected cardiomyocytes from hypoxic injury and raised CBS levels in a concentration-dependent manner. Different fromin vivoresults, however, CSE or 3-MST expression did not change. NaHS treatment increased the activity of CSE/CBS but not of 3-MST. When CSE was either knocked down (in vitro) or knocked out (in vivo), H2S levels significantly decreased, which subsequently exacerbated the ischaemic injury. Meanwhile, the expressions of CBS and 3-MST increased due to compensation.Conclusions. Exogenous H2S treatment changed the expressions of three H2S-producing enzymes and H2S levels after MI, suggesting a new and indirect regulatory mechanism for H2S production and its contribution to cardiac protection. Endogenous H2S plays an important role in protecting ischaemic tissue after MI.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Kun Zhao ◽  
Chuanxi Yang ◽  
Jing Zhang ◽  
Wei Sun ◽  
Bin Zhou ◽  
...  

AbstractMyocardial infarction (MI), one of the most severe types of heart attack, exerts a strong negative effect on heart muscle by causing a massive and rapid loss of cardiomyocytes. However, the existing therapies do little to improve cardiac regeneration. Due to the role of methyltransferase-like 3 (METTL3) in the physiological proliferation of cardiomyocytes, we aimed to determine whether METTL3 could also promote cardiomyocyte proliferation under pathological conditions and to elucidate the underlying mechanism. The effects of METTL3 on cardiomyocyte proliferation and apoptosis were investigated in an in vivo rat model of MI and in an in vitro model of neonatal rat cardiomyocytes (NRCMs) exposed to hypoxia. We found that METTL3 expression was downregulated in hypoxia-exposed NRCMs and MI-induced rats. Furthermore, METTL3 pretreatment enhanced cardiomyocyte proliferation and inhibited cardiomyocyte apoptosis under hypoxic or MI conditions, and silencing METTL3 had the opposite effects. Additionally, METTL3 overexpression upregulated miR-17-3p expression. The miR-17-3p agomir mimicked the pro-proliferative and antiapoptotic effects of METTL3 in hypoxia-exposed cells or rats with MI, while the miR-17-3p antagomir blocked these effects. Additionally, pretreatment with the RNA-binding protein DGCR8 also hampered the protective role of METTL3 in hypoxia-exposed cells. Overall, the current study indicated that METTL3 could improve cardiomyocyte proliferation and subsequently ameliorate MI in rats by upregulating proliferation-related miR-17-3p in a DGCR8-dependent pri-miRNA-processing manner.


2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi37-vi37
Author(s):  
Amber Kerstetter-Fogle ◽  
Peggy Harris ◽  
Harry Hoffman ◽  
Anthony Sloan ◽  
Theresa Elder ◽  
...  

Abstract INTRODUCTION Glioblastomas (GBM) are the most common and malignant primary brain tumors. Their rapid growth and invasion into neuronal parenchyma is devastating, with limited treatment options. Genomic alterations have been extensively studied in gliomas tumors, including aberrations of the Slit-Robo pathway genes. The Slit family of secreted proteins modulates migration of somatic cells during development and mediate their effect by binding to its receptor Roundabout (Robo). Genes in the Slit-Robo pathways have been shown to be inactivated by promoter hypermethylation in a number of human cancers. We hypothesize that Slit-Robo signaling pathways are modulated via promotor methylation, controlling GBM malignancy and regulating the invasive capacity of glioma stem cells (GSCs). METHODS We characterized expression of mRNA and protein via real-time PCR and Western blots in primary GBM tissue. We then assessed whether epigenetic alterations correlate with Slit-Robo expression by conducting in vitro demethylation assays in patient derived GSCs followed by real-time PCR. We conducted invasion assays to elucidate the role of Slit in GSC invasion. RESULTS The Cancer Genome Atlas indicates a negative correlation between Robo2 expression and glioma patient survival (17.1 months versus 37.4 months; p < 1.4E-4). We discovered differential expression of the Slit (1-3) and Robo (2, 3) genes and protein of up to 8-fold between grades 3 and 4 astrocytomas (8.34 versus 4.73 density). Treating patient derived glioma stem cells with 5-aza-2-deoxycytidine results in induction in Slit-Robo gene expression ranging from 5 – 40-fold (p < 0.01). Addition of Slit 2 and 3 in an invasion assay induced migration of GSCs in a differential and concentration dependent manner of 10 - 25% (p < 0.05). CONCLUSIONS Our results suggest that promoter methylation and gene expression of the Slit-Robo genes correlates with protein expression, tumor invasiveness, and prognosis and a potential therapeutic target.


2019 ◽  
Vol 26 (7) ◽  
pp. 494-501 ◽  
Author(s):  
Sameer Suresh Bhagyawant ◽  
Dakshita Tanaji Narvekar ◽  
Neha Gupta ◽  
Amita Bhadkaria ◽  
Ajay Kumar Gautam ◽  
...  

Background: Diabetes and hypertension are the major health concern and alleged to be of epidemic proportions. This has made it a numero uno subject at various levels of investigation. Glucosidase inhibitor provides the reasonable option in treatment of Diabetes Mellitus (DM) as it specifically targets post prandial hyperglycemia. The Angiotensin Converting Enzyme (ACE) plays an important role in hypertension. Therefore, inhibition of ACE in treatment of elevated blood pressure attracts special interest of the scientific community. Chickpea is a food legume and seeds contain carbohydrate binding protein- a lectin. Some of the biological properties of this lectin hitherto been elucidated. Methods: Purified by ion exchange chromatography, chickpea lectin was tested for its in vitro antioxidant, ACE-I inhibitory and anti-diabetic characteristic. Results: Lectin shows a characteristic improvement over the synthetic drugs like acarbose (oral anti-diabetic drug) and captopril (standard antihypertensive drug) when, their IC50 values are compared. Lectin significantly inhibited α-glucosidase and α-amylase in a concentration dependent manner with IC50 values of 85.41 ± 1.21 ҝg/ml and 65.05 ± 1.2 µg/ml compared to acarbose having IC50 70.20 ± 0.47 value of µg/ml and 50.52 ± 1.01 µg/ml respectively. β-Carotene bleaching assay showed antioxidant activity of lectin (72.3%) to be as active as Butylated Hydroxylanisole (BHA). In addition, lectin demonstrated inhibition against ACE-I with IC50 value of 57.43 ± 1.20 µg/ml compared to captopril. Conclusion: Lectin demonstrated its antioxidant character, ACE-I inhibition and significantly inhibitory for α-glucosidase and α-amylase seems to qualify as an anti-hyperglycemic therapeutic molecule. The biological effects of chickpea lectin display potential for reducing the parameters of medically debilitating conditions. These characteristics however needs to be established under in vivo systems too viz. animals through to humans.


Nutrients ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 123
Author(s):  
Natalia K. Kordulewska ◽  
Justyna Topa ◽  
Małgorzata Tańska ◽  
Anna Cieślińska ◽  
Ewa Fiedorowicz ◽  
...  

Lipopolysaccharydes (LPS) are responsible for the intestinal inflammatory reaction, as they may disrupt tight junctions and induce cytokines (CKs) secretion. Osthole has a wide spectrum of pharmacological effects, thus its anti-inflammatory potential in the LPS-treated Caco-2 cell line as well as in Caco-2/THP-1 and Caco-2/macrophages co-cultures was investigated. In brief, Caco-2 cells and co-cultures were incubated with LPS to induce an inflammatory reaction, after which osthole (150–450 ng/mL) was applied to reduce this effect. After 24 h, the level of secreted CKs and changes in gene expression were examined. LPS significantly increased the levels of IL-1β, -6, -8, and TNF-α, while osthole reduced this effect in a concentration-dependent manner, with the most significant decrease when a 450 ng/mL dose was applied (p < 0.0001). A similar trend was observed in changes in gene expression, with the significant osthole efficiency at a concentration of 450 ng/μL for IL1R1 and COX-2 (p < 0.01) and 300 ng/μL for NF-κB (p < 0.001). Osthole increased Caco-2 monolayer permeability, thus if it would ever be considered as a potential drug for minimizing intestinal inflammatory symptoms, its safety should be confirmed in extended in vitro and in vivo studies.


2021 ◽  

Myocardial infarction is a serious representation of cardiovescular disease, MicroRNAs play a role in modifying I/R injury and myocardial infarct remodeling. The present study therefore examined the potential role of miR-187 in cardiac I/R injury and its underlying mechanisms. miR-187 was inhibited or overexpressed in cardiomyocytes H/R models by pretreatment with miR-187 mimic or inhibitor to confirm the function of miR-187 in H/R. DYRK2 was inhibited or overexpressed in cardiomyocytes H/R models by pretreatment with DYRK2 inhibitor. A myocardium I/R mouse model was established. Circulating levels of miR-187 or DYRK2 was detected by quantitative realtime PCR and protein expression was detected by western blotting. The cell viability in all groups was determined by MTT assay and the apoptosis ratio was detected by flow cytometry after staining with Annexin V-FITC. The effect of miR-187 on cellular ROS generation was examined by DCFH-DA. The level of lipid peroxidation and SOD expression were determined by MDA and SOD assay. The findings indicated that miR-187 may be a possible regulator in the protective effect of H/R-induced cardiomyocyte apoptosis, cellular oxidative stress and leaded to DYRK2 suppression at a posttranscriptional level. Moreover, the improvement of miR-187 on H/R-induced cardiomyocyte injury contributed to the obstruction of DYRK2 expression. In addition, these results identified DYRK2 as the functional downstream target of miR-187 regulated myocardial infarction and oxidative stress.These present work provided the first insight into the function of miR-187 in successfully protect cardiomyocyte both in vivo and in vitro, and such a protective effect were mediated through the regulation of DYRK2 expression.


2021 ◽  
Vol 11 ◽  
Author(s):  
Dong Chen ◽  
Yaqin Wang ◽  
Feiya Yang ◽  
Adili Keranmu ◽  
Qingxin Zhao ◽  
...  

An increasing number of studies have shown that circRNAs are closely related to the carcinogenesis and development of prostate cancer (PCa). However, little is known about the effect of the biological functions of circRNAs on the enzalutamide resistance of PCa. Through bioinformatic analysis and experiments, we investigated the expression pattern of circRNAs in enzalutamide-resistant PCa cells. Quantitative real-time PCR was used to detect the expression of circRAB3IP, and plasmids that knock down or overexpress circRAB3IP were used to evaluate its effect on the enzalutamide sensitivity of PCa cells. Mechanistically, we explored the potential regulatory effects of eIF4A3 and LEF1 on the biogenesis of circRAB3IP. Our in vivo and in vitro data indicated that increased expression of circRAB3IP was found in enzalutamide-resistant PCa, and knockdown of circRAB3IP significantly enhanced enzalutamide sensitivity in PCa cells. However, upregulation of circRAB3IP resulted in the opposite effects. Further mechanistic research demonstrated that circRAB3IP could regulate the expression of serum and glucocorticoid-regulated kinase 1 (SGK1) by serving as a sponge that directly targets miR-133a-3p/miR-133b. Then, we showed that circRAB3IP partially exerted its biological functions via SGK1 signaling. Furthermore, we discovered that eIF4A3 and LEF1 might increase circRAB3IP expression in PCa.


Author(s):  
Mohammad Reza Shiran ◽  
Elham Mahmoudian ◽  
Abolghasem Ajami ◽  
Seyed Mostafa Hosseini ◽  
Ayjamal Khojasteh ◽  
...  

Abstract Objectives Angiogenesis is the most important challenge in breast cancer treatment. Recently, scientists become interesting in rare natural products and intensive researches was performed to identify their pharmacological profile. Auraptene shows helpful effects such as cancer chemo-preventive, anti-inflammatory, anti-oxidant, immuno-modulatory. In this regard, we investigated the anti-angiogenesis effect of Auraptene in in-vitro and in-vivo model of breast cancer. Methods In this study, 4T, MDA-MB-231 and HUVEC cell lines were used. The proliferation study was done by MTT assay. For tube formation assay, 250 matrigel, 1 × 104 HUVEC treated with Auraptene, 20 ng/mL EGF, 20 ng/mL bFGF and 20 ng/mL VEGF were used. Gene expression of important gene related to angiogenesis in animal model of breast cancer was investigated by Real-time PCR. Protein expression of VCAM-1 and TNFR-1 gene related to angiogenesis in animal model of breast cancer was investigated by western-blot. Results Auraptene treatment led to reduction in cell viability of MDA-MB-231 in a concentration-dependent manner. Also, we observed change in the number of tubes or branches formed by cells incubated with 40 and 80 μM Auraptene. Auraptene effect the gene expression of important gene related to angiogenesis (VEGF, VEGFR2, COX2, IFNɣ). Moreover, the western blot data exhibited that Auraptene effect the protein expression of VCAM-1 and TNFR-1. Conclusions Overall, this study shows that Auraptene significantly suppressed angiogenesis via down-regulation of VEGF, VEGFR2, VCAM-1, TNFR-1, COX-2 and up-regulation of IFNγ.


Real-time PCR offers a wide area of application to analyze the role of gene activity in various biological aspects at the molecular level with higher specificity, sensitivity and the potential to troubleshoot with post-PCR processing and difficulties. With the recent advancement in the development of functional tissue graft for the regeneration of damaged/diseased tissue, it is effective to analyze the cell behaviour and differentiation over tissue construct toward specific lineage through analyzing the expression of an array of specific genes. With the ability to collect data in the exponential phase, the application of Real-Time PCR has been expanded into various fields such as tissue engineering ranging from absolute quantification of gene expression to determine neo-tissue regeneration and its maturation. In addition to its usage as a research tool, numerous advancements in molecular diagnostics have been achieved, including microbial quantification, determination of gene dose and cancer research. Also, in order to consistently quantify mRNA levels, Northern blotting and in situ hybridization (ISH) methods are less preferred due to low sensitivity, poor precision in detecting gene expression at a low level. An amplification step is thus frequently required to quantify mRNA amounts from engineered tissues of limited size. When analyzing tissue-engineered constructs or studying biomaterials–cells interactions, it is pertinent to quantify the performance of such constructs in terms of extracellular matrix formation while in vitro and in vivo examination, provide clues regarding the performance of various tissue constructs at the molecular level. In this chapter, our focus is on Basics of qPCR, an overview of technical aspects of Real-time PCR; recent Protocol used in the lab, primer designing, detection methods and troubleshooting of the experimental problems.


2020 ◽  
Vol 21 (9) ◽  
pp. 3359
Author(s):  
Zoltán Giricz ◽  
András Makkos ◽  
Rolf Schreckenberg ◽  
Jochen Pöling ◽  
Holger Lörchner ◽  
...  

Swiprosin-1 (EFhD2) is a molecule that triggers structural adaptation of isolated adult rat cardiomyocytes to cell culture conditions by initiating a process known as cell spreading. This process mimics central aspects of cardiac remodeling, as it occurs subsequent to myocardial infarction. However, expression of swiprosin-1 in cardiac tissue and its regulation in vivo has not yet been addressed. The expression of swiprosin-1 was analyzed in mice, rat, and pig hearts undergoing myocardial infarction or ischemia/reperfusion with or without cardiac protection by ischemic pre- and postconditioning. In mouse hearts, swiprosin-1 protein expression was increased after 4 and 7 days in myocardial infarct areas specifically in cardiomyocytes as verified by immunoblotting and histology. In rat hearts, swiprosin-1 mRNA expression was induced within 7 days after ischemia/reperfusion but this induction was abrogated by conditioning. As in cultured cardiomyocytes, the expression of swiprosin-1 was associated with a coinduction of arrestin-2, suggesting a common mechanism of regulation. Rno-miR-32-3p and rno-miR-34c-3p were associated with the regulation pattern of both molecules. Moreover, induction of swiprosin-1 and ssc-miR-34c was also confirmed in the infarct zone of pigs. In summary, our data show that up-regulation of swiprosin-1 appears in the postischemic heart during cardiac remodeling and repair in different species.


Sign in / Sign up

Export Citation Format

Share Document