scholarly journals Hexarelin Modulation of MAPK and PI3K/Akt Pathways in Neuro-2A Cells Inhibits Hydrogen Peroxide—Induced Apoptotic Toxicity

2021 ◽  
Vol 14 (5) ◽  
pp. 444
Author(s):  
Ramona Meanti ◽  
Laura Rizzi ◽  
Elena Bresciani ◽  
Laura Molteni ◽  
Vittorio Locatelli ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Cell Viability ◽  
Caspase 3 ◽  
Mrna Levels ◽  
Protective Effects ◽  
Neuroprotective Effects ◽  
Caspase 7 ◽  
Induced Apoptosis

Hexarelin, a synthetic hexapeptide, exerts cyto-protective effects at the mitochondrial level in cardiac and skeletal muscles, both in vitro and in vivo, may also have important neuroprotective bioactivities. This study examined the inhibitory effects of hexarelin on hydrogen peroxide (H2O2)-induced apoptosis in Neuro-2A cells. Neuro-2A cells were treated for 24 h with various concentrations of H2O2 or with the combination of H2O2 and hexarelin following which cell viability and nitrite (NO2−) release were measured. Cell morphology was also documented throughout and changes arising were quantified using Image J skeleton and fractal analysis procedures. Apoptotic responses were evaluated by Real-Time PCR (caspase-3, caspase-7, Bax, and Bcl-2 mRNA levels) and Western Blot (cleaved caspase-3, cleaved caspase-7, MAPK, and Akt). Our results indicate that hexarelin effectively antagonized H2O2-induced damage to Neuro-2A cells thereby (i) improving cell viability, (ii) reducing NO2− release and (iii) restoring normal morphologies. Hexarelin treatment also reduced mRNA levels of caspase-3 and its activation, and modulated mRNA levels of the BCL-2 family. Moreover, hexarelin inhibited MAPKs phosphorylation and increased p-Akt protein expression. In conclusion, our results demonstrate neuroprotective and anti-apoptotic effects of hexarelin, suggesting that new analogues could be developed for their neuroprotective effects.

scholarly journals Tetramethylpyrazine Attenuates the Endotheliotoxicity and the Mitochondrial Dysfunction by Doxorubicin via 14-3-3γ/Bcl-2

2019 ◽  
Vol 2019 ◽  
pp. 1-20 ◽  
Author(s):  
Bin Yang ◽  
Hongwei Li ◽  
Yang Qiao ◽  
Qing Zhou ◽  
Shuping Chen ◽  
...  
Keyword(s):  
Cell Viability ◽  
Vascular Endothelium ◽  
Caspase 3 ◽  
Vascular Tissue ◽  
Ros Generation ◽  
Protective Effects ◽  
Histopathological Changes ◽  
Mptp Opening

Doxorubicin (Dox) with cardiotoxicity and endotheliotoxicity limits its clinical application for cancer. The toxicitic mechanism involves excess ROS generation. 14-3-3s have the protective effects on various injured tissues and cells. Tetramethylpyrazine (TMP) is an alkaloid extracted from the rhizome of Ligusticum wallichii and has multiple bioactivities. We hypothesize that TMP has the protective effects on vascular endothelium by upregulating 14-3-3γ. To test the hypothesis, Dox-induced endotheliotoxicity was used to establish vascular endothelium injury models in mice and human umbilical vein endothelial cells. The effects of TMP were assessed by determining thoracic aortic strips’ endothelium-dependent dilation (EDD), as well as LDH, CK, caspase-3, SOD, CAT, GSH-Px activities and MDA level in serum, apoptotic rate, and histopathological changes of vascular tissue (in vivo). Also, cell viability, LDH and caspase-3 activities, ROS generation, levels of NAD+/NADH and GSH/GSSG, MMP, mPTP opening, and apoptotic rate were evaluated (in vitro). The expression of 14-3-3γ and Bcl-2, as well as phosphorylation of Bad (S112), were determined by Western blot. Our results showed that Dox-induced injury to vascular endothelium was decreased by TMP via upregulating 14-3-3γ expression in total protein and Bcl-2 expression in mitochondria, activating Bad (S112) phosphorylation, maintaining EDD, reducing LDH, CK, and caspase-3 activities, thereby causing a reduction in apoptotic rate, and histopathological changes of vascular endothelium (in vivo). Furthermore, TMP increased cell viability and MMP levels, maintained NAD+/NADH, GSH/GSSG balance, decreased LDH and caspase-3 activities, ROS generation, mPTP opening, and apoptotic rate (in vitro). However, the protective effects to vascular endothelium of TMP were significantly canceled by pAD/14-3-3γ-shRNA, an adenovirus that caused knockdown 14-3-3γ expression, or ABT-737, a specific Bcl-2 inhibitor. In conclusion, this study is the first to demonstrate that TMP protects the vascular endothelium against Dox-induced injury via upregulating 14-3-3γ expression, promoting translocation of Bcl-2 to the mitochondria, closing mPTP, maintaining MMP, inhibiting RIRR mechanism, suppressing oxidative stress, improving mitochondrial function, and alleviating Dox-induced endotheliotoxicity.

Cyanidin-3-glucoside attenuates 4-hydroxynonenal- and visible light-induced retinal damage in vitro and in vivo

2019 ◽  
Vol 10 (5) ◽  
pp. 2871-2880 ◽  
Author(s):  
Yong Wang ◽  
Wentao Qi ◽  
Yazhen Huo ◽  
Ge Song ◽  
Hui Sun ◽  
...  
Keyword(s):  
Retinal Pigment Epithelial ◽  
Retinal Pigment ◽  
Retinal Pigment Epithelial Cells ◽  
Retinal Damage ◽  
Protective Effects ◽  
Pigment Epithelial ◽  
Induced Apoptosis ◽  
Pigment Epithelial Cells

Cyanidin-3-glucoside has efficient protective effects on 4-hydroxynonenal-induced apoptosis, senescence, and angiogenesis in retinal pigment epithelial cells.

scholarly journals Humanin is an endogenous activator of chaperone-mediated autophagy

2017 ◽  
Vol 217 (2) ◽  
pp. 635-647 ◽  
Author(s):  
Zhenwei Gong ◽  
Inmaculada Tasset ◽  
Antonio Diaz ◽  
Jaime Anguiano ◽  
Emir Tas ◽  
...  
Keyword(s):  
Quality Control ◽  
Cell Death ◽  
Heat Shock Protein 90 ◽  
Protective Effects ◽  
Neuroprotective Effects ◽  
Selective Degradation ◽  
Cytosolic Side ◽  
Chaperone Mediated Autophagy

Chaperone-mediated autophagy (CMA) serves as quality control during stress conditions through selective degradation of cytosolic proteins in lysosomes. Humanin (HN) is a mitochondria-associated peptide that offers cytoprotective, cardioprotective, and neuroprotective effects in vivo and in vitro. In this study, we demonstrate that HN directly activates CMA by increasing substrate binding and translocation into lysosomes. The potent HN analogue HNG protects from stressor-induced cell death in fibroblasts, cardiomyoblasts, neuronal cells, and primary cardiomyocytes. The protective effects are lost in CMA-deficient cells, suggesting that they are mediated through the activation of CMA. We identified that a fraction of endogenous HN is present at the cytosolic side of the lysosomal membrane, where it interacts with heat shock protein 90 (HSP90) and stabilizes binding of this chaperone to CMA substrates as they bind to the membrane. Inhibition of HSP90 blocks the effect of HNG on substrate translocation and abolishes the cytoprotective effects. Our study provides a novel mechanism by which HN exerts its cardioprotective and neuroprotective effects.

scholarly journals Hexarelin exerts neuroprotective and antioxidant effects against hydrogen peroxide-induced toxicity through the modulation of MAPK and PI3K/Akt patways in Neuro-2A cells

2020 ◽  
Author(s):  
Ramona Meanti ◽  
Laura Rizzi ◽  
Elena Bresciani ◽  
Laura Molteni ◽  
Vittorio Locatelli ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
Apoptotic Cell ◽  
Neuroblastoma Cell ◽  
Neuroblastoma Cell Line ◽  
Inhibitory Influence ◽  
No Production ◽  
Mrna Levels

AbstractHexarelin, a synthetic hexapeptide, protects cardiac and skeletal muscles by inhibiting apoptosis, both in vitro and in vivo. Moreover, evidence suggests that hexarelin could have important neuroprotective bioactivity.Oxidative stress and the generation of free radicals has been implicated in the etiologies of several neurodegenerative diseases, including amyotrophic lateral sclerosis, Parkinson’s disease, Alzheimer’s disease, Huntington’s disease and multiple sclerosis. In addition to direct oxidative stress, exogenous hydrogen peroxide (H2O2) can penetrate biological membranes and enhance the formation of other reactive oxygen species.The aim of this study was to examine the inhibitory influence of hexarelin on H2O2-induced apoptosis in Neuro-2A cells, a mouse neuroblastoma cell line. Our results indicate that H2O2 reduced the viability of Neuro-2A cells in a dose-related fashion. Furthermore, H2O2 induced significant changes in the morphology of Neuro-2A cells, reflected in the formation of apoptotic cell bodies, and an increase of nitric oxide (NO) production. Hexarelin effectively antagonized H2O2 oxidative damage to Neuro-2A cells as indicated by improved cell viability, normal morphology and reduced nitrite (NO2−) release. Hexarelin treatment of Neuro-2A cells also reduced mRNA levels of caspases−3 and −7 and those of the pro-apoptotic molecule Bax; by contrast, hexarelin treatment increased anti-apoptotic Bcl-2 mRNA levels. Hexarelin also reduced MAPKs phosphorylation induced by H2O2 and concurrently increased p-Akt protein expression.In conclusion, our results identify several neuroprotective and anti-apoptotic effects of hexarelin. These properties suggest that further investigation of hexarelin as a neuroprotective agent in an investigational and therapeutic context are merited.

scholarly journals Salmonella-Induced Caspase-2 Activation in Macrophages

2000 ◽  
Vol 192 (7) ◽  
pp. 1035-1046 ◽  
Author(s):  
Veronika Jesenberger ◽  
Katarzyna J. Procyk ◽  
Junying Yuan ◽  
Siegfried Reipert ◽  
Manuela Baccarini
Keyword(s):  
Type Iii Secretion ◽  
Caspase 3 ◽  
Secretion System ◽  
Caspase 1 ◽  
Chemical Inhibition ◽  
Induction Of Apoptosis ◽  
Caspase 2 ◽  
Induced Apoptosis

The enterobacterial pathogen Salmonella induces phagocyte apoptosis in vitro and in vivo. These bacteria use a specialized type III secretion system to export a virulence factor, SipB, which directly activates the host's apoptotic machinery by targeting caspase-1. Caspase-1 is not involved in most apoptotic processes but plays a major role in cytokine maturation. We show that caspase-1–deficient macrophages undergo apoptosis within 4–6 h of infection with invasive bacteria. This process requires SipB, implying that this protein can initiate the apoptotic machinery by regulating components distinct from caspase-1. Invasive Salmonella typhimurium targets caspase-2 simultaneously with, but independently of, caspase-1. Besides caspase-2, the caspase-1–independent pathway involves the activation of caspase-3, -6, and -8 and the release of cytochrome c from mitochondria, none of which occurs during caspase-1–dependent apoptosis. By using caspase-2 knockout macrophages and chemical inhibition, we establish a role for caspase-2 in both caspase-1–dependent and –independent apoptosis. Particularly, activation of caspase-1 during fast Salmonella-induced apoptosis partially relies on caspase-2. The ability of Salmonella to induce caspase-1–independent macrophage apoptosis may play a role in situations in which activation of this protease is either prevented or uncoupled from the induction of apoptosis.

MicroRNA-204-3p Attenuates High Glucose-Induced MPC5 Podocytes Apoptosis by Targeting Braykinin B2 Receptor

2018 ◽  
Vol 127 (06) ◽  
pp. 387-395 ◽  
Author(s):  
Xu Han ◽  
Qiaobei Li ◽  
Chunyan Wang ◽  
Yinyan Li
Keyword(s):  
Cell Viability ◽  
High Glucose ◽  
Protective Role ◽  
Luciferase Reporter ◽  
Gene And Protein Expression ◽  
Glucose Treatment ◽  
Apoptosis Gene ◽  
Induced Apoptosis

Abstract Background Previous study has been reported that braykinin B2 receptor (Bdkrb2) involves in high glucose-induced renal and podocytes injuries. However, there have been some studies with contradictory results that Bdkrb2 has a protective effect on hyperglycemia-induced injuries in vivo and in vitro. The purpose of the present study was carried out to further investigate the post-transcriptional regulatory mechanism of microRNA (miR) in high glucose-treated podocytes by targeting Bdkrb2 signaling in vitro. Methods The CCK-8 and flow cytometry were performed to measure the cell viability and apoptosis. Gene and protein expression were assayed by RT-qPCR and western blotting, respectively. Results High glucose treatment decreased cell viability and induced membrane and DNA damage, as well as apoptosis in podocytes. High glucose treatment also increased the expression of Bdkrb2, which was blocked by miR-204-3p mimics transfection in podocytes. Bioinformatics and luciferase reporter activity showed that miR-204-3p was directly targeted to the 3′-untranslated region (3′-UTR) of Bdkrb2. High glucose-induced apoptosis and dysfunction in podocytes were reserved by miR-204-3p mimics transfection, while the effects of miR-204-3p mimics in high glucose-treated podocytes were neutralized by overexpressed Bdkrb2. Conclusions These findings suggested that miR-204-3p may play a protective role in high glucose-induced apoptosis and dysfunction in podocytes through down-regulation of Bdkrb2.

scholarly journals Apelin-13 Protects Dopaminergic Neurons against Rotenone—Induced Neurotoxicity through the AMPK/mTOR/ULK-1 Mediated Autophagy Activation

2020 ◽  
Vol 21 (21) ◽  
pp. 8376
Author(s):  
Peng Chen ◽  
Youcui Wang ◽  
Leilei Chen ◽  
Ning Song ◽  
Junxia Xie
Keyword(s):  
Dopaminergic Neurons ◽  
Substantia Nigra Pars Compacta ◽  
Protective Effects ◽  
Gut Peptides ◽  
Neuroprotective Effects ◽  
Compound C ◽  
Apelin Receptor ◽  
Signaling Activation

Parkinson’s disease (PD) is characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta. Several brain–gut peptides are able to exert neuroprotective effects on the nigrostriatal dopaminergic system. Apelin-13 is a neuropeptide, conveying potential neuroprotective activities. However, whether, and how, apelin-13 could antagonize rotenone-induced neurotoxicity has not yet been elucidated. In the present study, rotenone-treated SH-SY5Y cells and rats were used to clarify whether apelin-13 has protective effects on dopaminergic neurons, both in vivo and in vitro. The results showed that apelin-13 could protect SH-SY5Y cells from rotenone-induced injury and apoptosis. Apelin-13 was able to activate autophagy, and restore rotenone induced autophagy impairment in SH-SY5Y cells, which could be blocked by the autophagy inhibitor 3-Methyladenine. Apelin-13 activated AMPK/mTOR/ULK-1 signaling, AMPKα inhibitor compound C, as well as apelin receptor blockage via siRNA, which could block apelin-13-induced signaling activation, autophagy activation, and protective effects, in rotenone-treated SH-SY5Y cells. These results indicated that apelin-13 exerted neuroprotective properties against rotenone by stimulating AMPK/mTOR/ULK-1 signaling-mediated autophagy via the apelin receptor. We also observed that intracerebroventricular injection of apelin-13 could alleviate nigrostriatal dopaminergic neuron degeneration in rotenone-treated rats. Our findings provide new insights into the mechanism by which apelin-13 might attenuate neurotoxicity in PD.

The Kinase Inhibitor Sorafenib Can Disrupt the Survival Support Provided by the Microenvironment and Induce Apoptosis of Chronic Lymphocytic Leukemia Cells

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 47-47
Author(s):  
Jessie-F Fecteau ◽  
Ila Bharati ◽  
Morgan O'Hayre ◽  
Tracy Handel ◽  
Thomas J. Kipps ◽  
...  
Keyword(s):  
Single Dose ◽  
Cell Viability ◽  
Cell Survival ◽  
Kinase Inhibitor ◽  
Vehicle Control ◽  
Lymphocytic Leukemia ◽  
Viable Cells ◽  
Induced Apoptosis

Abstract Abstract 47 Chronic Lymphocytic Leukemia (CLL) is characterized by an accumulation of mature monoclonal B cells in the blood, secondary lymphoid tissue, and marrow. Despite their accumulation in vivo, CLL cells undergo spontaneous apoptosis in vitro unless rescued by extrinsic factors derived from the leukemia-cell microenvironment. Monocyte-derived Nurse-Like Cells (NLCs) and Marrow Stromal Cells (MSCs), representing the leukemic microenvironment, have been show to sustain CLL cell survival and more importantly to protect CLL cells from drug-induced apoptosis in vitro and possibly in vivo. Such protective niches are thought to prevent current therapies from achieving complete remission in patients. Investigating the mechanism(s) by which cells from the microenvironment promote CLL cell survival, particularly the signaling pathways triggered, will allow for the identification of new therapeutic targets aiming to disrupt these protective interactions. NLCs and MSCs have been shown to produce the chemokine SDF-1 (CXCL12), which can enhance CLL cell survival. We recently found that ZAP-70+ aggressive CLL cells responded by an increased survival to this chemokine, compared to ZAP-70- indolent CLL cells, and that this response was accompanied by the activation of the ERK pathway. Attempting to abrogate this survival pathway, we found that sorafenib (BAY 43–9006, Nexavar) a multi-kinase inhibitor targeting among others Raf kinases and thereby the RAF/MEK/ERK pathway, strongly reduced CLL cell viability in a time and dose dependent manner. A regimen of one single dose of 10uM of sorafenib significantly reduced CLL cell viability to 18+/−10% cells after 48hrs compared to vehicle control (DMSO; 100%; n=5). The daily addition of 1uM sorafenib also significantly decreased CLL cell viability, leading to 31+/−21% and 11+/−5% viable cells after 6 and 7 days respectively, compared to DMSO (n=5). More importantly, our results show that sorafenib induces CLL cell death in the presence of NLCs and MSCs. A single dose of sorafenib (10uM) rapidly decreased the fraction of viable CLL cells overtime, passing from 40+/−16% after 1 day to 10+/−3% after 4 days (n=4) in the context of NLCs and to 25+/−3% after 2 days and 14+/−3% after 4 days in the presence of MSCs, when compared to vehicle control (>80%; n=4). In the presence of NLCs, the 1uM daily regimen also uncovered an increased sensitivity of ZAP-70+ CLL cells to this drug, reducing in 6 days their viability to 13+/−2% (n=4), which approximately half the fraction of viable cells remaining in the ZAP-70- group (40+/−16%; n=7). We next studied sorafenib-mediated cytotoxicity by investigating its impact on the expression of pro-survival molecules. We found that Mcl-1, Bcl-2 and Bcl-xL protein expression was reduced in CLL cells compared to vehicle control, when stimulated with CXCL12 (n=3). In the presence of NLCs and MSCs, only Mcl-1 expression was downregulated, which was also associated with a reduction of the active form of the transcription factor CREB, involved in Mcl-1 expression. Because Mcl-1 expression can be regulated by ERK and AKT pathways, we next investigated if they were abrogated by sorafenib. We indeed found that MEK, ERK, and AKT activation were reduced by this inhibitor compared to vehicle control (n=3). We therefore propose that the cytotoxic effect of sorafenib on CLL cells is due to its interference with at least these two major survival pathways. Since sorafenib caused apoptosis of CLL cells in context of the microenvironment, we reasoned that it might also cause apoptosis of chemotherapy resistant CLL cells. To test this hypothesis, we studied cells from fludarabine-refractory patients. In the presence of NLCs, a single dose of 10uM sorafenib induced a significant reduction in CLL cell viability after 2 days: only 4+/−2% viable cells remained compared to 78+/−12% for the vehicle control (n=4). A comparable observation was made in the presence of MSCs: sorafenib potently induced apoptosis, leaving 12+/−3% live cells after 2 days, compared to vehicle control (71+/−16%; n=4). These results are very promising as they suggest that sorafenib could be an effective novel therapeutic for CLL, affecting the viability of the leukemic cells even in protective niches. Since sorafenib has been approved by the FDA in 2007 for the treatment of advanced hepatocellular carcinoma, a pilot study is currently being planned at UCSD to evaluate the potential of this drug in CLL in vivo. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Periplocin Extracted from Cortex Periplocae Induced Apoptosis of Gastric Cancer Cells via the ERK1/2-EGR1 Pathway

2016 ◽  
Vol 38 (5) ◽  
pp. 1939-1951 ◽  
Author(s):  
Lei Li ◽  
Lian-Mei Zhao ◽  
Su-li Dai ◽  
Wen-Xuan Cui ◽  
Hui-Lai Lv ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Cell Viability ◽  
Cancer Cells ◽  
Inhibitory Effect ◽  
Tunel Staining ◽  
Dependent Manner ◽  
Gastric Cancer Cells ◽  
Induced Apoptosis

Background/Aims: Periplocin is extracted from the traditional herbal medicine cortex periplocae, which has been reported to suppress the growth of cancer cells. However, little is known about its effect on gastric cancer cells. Methods: Gastric cancer cells were treated with periplocin, and cell viability was assessed using MTS assay. Flow cytometry and TUNEL staining were performed to evaluate apoptosis, and protein expression was examined by western blotting. Microarray analysis was used to screen for changes in related genes. Results: We found that periplocin had an inhibitory effect on gastric cancer cell viability in a dose-dependent manner. Periplocin inhibited cell viability via the ERK1/2-EGR1 pathway to induce apoptosis. Periplocin also inhibited the growth of tumor xenografts and induced apoptosis in vivo. Conclusion: Our results show that periplocin inhibits the proliferation of gastric cancer cells and induces apoptosis in vitro and in vivo, indicating its potential to be used as an antitumor drug.

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