scholarly journals Aurantiamide acetate suppresses the growth of malignant gliomas in vitro and in vivo by inhibiting autophagic flux

2015 ◽  
Vol 19 (5) ◽  
pp. 1055-1064 ◽  
Author(s):  
Yi Yang ◽  
Li‐hui Zhang ◽  
Bing‐xian Yang ◽  
Jin‐kui Tian ◽  
Lin Zhang
Keyword(s):  
Malignant Gliomas ◽  
Autophagic Flux ◽  
Aurantiamide Acetate

scholarly journals Adenosine A2A receptor signaling promotes FoxO associated autophagy in chondrocytes

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Benjamin Friedman ◽  
Carmen Corciulo ◽  
Cristina M. Castro ◽  
Bruce N. Cronstein
Keyword(s):  
Cell Line ◽  
Metabolic Stress ◽  
Human Cell Line ◽  
Adenosine A2a Receptor ◽  
Autophagic Flux ◽  
A2a Receptor ◽  
Adenosine A2a ◽  
A2ar Agonist

AbstractAutophagy, a homeostatic pathway upregulated during cellular stress, is decreased in osteoarthritic chondrocytes and this reduction in autophagy is thought to contribute to the development and progression of osteoarthritis (OA). The adenosine A2A receptor (A2AR) is a potent anti-inflammatory receptor and deficiency of this receptor leads to the development of OA in mice. Moreover, treatment using liposomally conjugated adenosine or a specific A2AR agonist improved joint scores significantly in both rats with post-traumatic OA (PTOA) and mice subjected to a high fat diet obesity induced OA. Importantly, A2AR ligation is beneficial for mitochondrial health and metabolism in vitro in primary and the TC28a2 human cell line. An additional set of metabolic, stress-responsive, and homeostatic mediators include the Forkhead box O transcription factors (FoxOs). Data has shown that mouse FoxO knockouts develop early OA with reduced cartilage autophagy, indicating that FoxO-induced homeostasis is important for articular cartilage. Given the apparent similarities between A2AR and FoxO signaling, we tested the hypothesis that A2AR stimulation improves cartilage function through activation of the FoxO proteins leading to increased autophagy in chondrocytes. We analyzed the signaling pathway in the human TC28a2 cell line and corroborated these findings in vivo in a metabolically relevant obesity-induced OA mouse model. We found that A2AR stimulation increases activation and nuclear localization of FoxO1 and FoxO3, promotes an increase in autophagic flux, improves metabolic function in chondrocytes, and reduces markers of apoptosis in vitro and reduced apoptosis by TUNEL assay in vivo. A2AR ligation additionally enhances in vivo activation of FoxO1 and FoxO3 with evidence of enhanced autophagic flux upon injection of the liposome-associated A2AR agonist in a mouse obesity-induced OA model. These findings offer further evidence that A2AR may be an excellent target for promoting chondrocyte and cartilage homeostasis.

scholarly journals 5-O-Demethylnobiletin Alleviates CCl4-Induced Acute Liver Injury by Equilibrating ROS-Mediated Apoptosis and Autophagy Induction

2021 ◽  
Vol 22 (3) ◽  
pp. 1083
Author(s):  
Sukkum Ngullie Chang ◽  
Se Ho Kim ◽  
Debasish Kumar Dey ◽  
Seon Min Park ◽  
Omaima Nasif ◽  
...  
Keyword(s):  
Liver Injury ◽  
Acute Liver Injury ◽  
Elevated Serum ◽  
In Vitro Study ◽  
Biological Properties ◽  
Autophagic Flux ◽  
Serum Aminotransferase ◽  
Ccl4 Treatment

Polymethoxyflavanoids (PMFs) have exhibited a vast array of therapeutic biological properties. 5-O-Demethylnobiletin (5-DN) is one such PMF having anti-inflammatory activity, yet its role in hepatoprotection has not been studied before. Results from in vitro study revealed that 5-DN did not exert a high level of cytotoxicity on HepG2 cells at 40 μM, and it was able to rescue HepG2 cell death induced by carbon tetrachloride (CCl4). Subsequently, we investigated acute liver injury on BALB/c mice induced by CCl4 through the intraperitoneal injection of 1 mL/kg CCl4 and co-administration of 5-DN at (1 and 2 mg/kg) by oral gavage for 15 days. The results illustrated that treatment with 5-DN attenuated CCl4-induced elevated serum aminotransferase (AST)/alanine aminotransferase (ALT) ratio and significantly ameliorated severe hepatic damage such as inflammation and fibrosis evidenced through lesser aberrations in the liver histology of 5-DN dose groups. Additionally, 5-DN efficiently counteracted and equilibrated the production of ROS accelerated by CCl4 and dramatically downregulated the expression of CYP2E1 vitally involved in converting CCl4 to toxic free radicals and also enhanced the antioxidant enzymes. 5-DN treatment also inhibited cell proliferation and inflammatory pathway abnormally regulated by CCl4 treatment. Furthermore, the apoptotic response induced by CCl4 treatment was remarkably reduced by enhanced Bcl-2 expression and noticeable reduction in Bax, Bid, cleaved caspase 3, caspase 9, and apaf-1 expression. 5-DN treatment also induced the conversion of LC3 and promoted the autophagic flux. Conclusively, 5-DN exhibited hepatoprotective effects in vitro and in vivo and prevented liver fibrosis induced by CCl4.

scholarly journals Multi-responsive nanofibers composite gel for local drug delivery to inhibit recurrence of glioma after operation

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Yufu Zhu ◽  
Jun Jia ◽  
Gang Zhao ◽  
Xuyang Huang ◽  
Lansheng Wang ◽  
...  
Keyword(s):  
Malignant Gliomas ◽  
Postoperative Recurrence ◽  
Local Drug Delivery ◽  
Recurrent Glioma ◽  
Mixed Solution ◽  
Composite Gel ◽  
Poly Propylene ◽  
Responsive Hydrogels

Abstract Background The postoperative recurrence of malignant gliomas has presented a clinical conundrum currently. Worse, there is no standard treatment for these recurrent tumours. Therefore, novel promising methods of clinical treatment are urgently needed. Methods In this study, we synthesized reactive oxygen species (ROS)-triggered poly(propylene sulfide)60 (PPS60) mixed with matrix metalloproteinases (MMPs)-responsive triglycerol monostearate (T) lipids and TMZ. The mixed solution could self-assemble at 50 ℃ to generate hydrogels with MMPs- and ROS-responsiveness. We explored whether the T/PPS + TMZ hydrogel could achieve the MMP- and ROS-responsive delivery of TMZ and exert anti-glioma regrowth effects in vitro and in vivo. These results demonstrated that the T/PPS + TMZ hydrogel significantly improved the curative effect of TMZ to inhibit postsurgical recurrent glioma. Results The results confirmed the responsive release of TMZ encapsulated in the T/PPS + TMZ hydrogel, and the hydrogel showed excellent performance against glioma in an incomplete glioma operation model, which indicated that the T/PPS + TMZ hydrogel effectively inhibited the growth of recurrent glioma. Conclusion In summary, we successfully developed injectable MMPs- and ROS-responsive hydrogels that could achieve the sustained release of TMZ in the surgical cavity to inhibit local recurrent glioma after surgery. Graphic abstract

scholarly journals EXTH-70. ENHANCEMENT OF ANTITUMOR ACTIVITY BY USING 5-ALA–MEDIATED SONODYNAMIC THERAPY TO INDUCE APOPTOSIS AND NECROSIS IN A MOUSE GLIOMA MODEL

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi97-vi97
Author(s):  
Satoshi Suehiro ◽  
Takanori Ohnishi ◽  
Akihiro Inoue ◽  
Daisuke Yamashita ◽  
Masahiro Nishikawa ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Malignant Gliomas ◽  
Glioma Cells ◽  
High Intensity Focused Ultrasound ◽  
Control Group ◽  
Normal Brain ◽  
Sonodynamic Therapy ◽  
Cytotoxic Effects

Abstract OBJECTIVE High invasiveness of malignant gliomas frequently causes local tumor recurrence. To control such recurrence, novel therapies targeted toward infiltrating glioma cells are required. Here, we examined cytotoxic effects of sonodynamic therapy (SDT) combined with a sonosensitizer, 5-aminolevulinic acid (5-ALA), on malignant gliomas both in vitro and in vivo. METHODS In vitro cytotoxicity of 5-ALA-SDT was evaluated in U87 and U251 glioma cells and in U251Oct-3/4 glioma stemlike cells. Treatment-related apoptosis was analyzed using flow cytometry. Intracellular reactive oxygen species (ROS) were measured and the role of ROS in treatment-related cytotoxicity was examined. Effects of 5-ALA-SDT with high-intensity focused ultrasound (HIFU) on tumor growth, survival of glioma-transplanted mice, and histological features of the mouse brains were investigated. RESULTS The 5-ALA-SDT inhibited cell growth and changed cell morphology. Flow cytometric analysis indicated that 5-ALA-SDT induced apoptotic cell death. The 5-ALA-SDT generated higher ROS than in the control group, and inhibition of ROS generation completely eliminated the cytotoxic effects of 5-ALA-SDT. In the in vivo study, 5-ALA-SDT with HIFU greatly prolonged survival of the tumor-bearing mice compared with that of the control group (p < 0.05). Histologically, 5-ALA-SDT produced mainly necrosis of the tumor tissue in the focus area and induced apoptosis of the tumor cells in the perifocus area around the target of the HIFU-irradiated field. Normal brain tissues around the ultrasonic irradiation field of HIFU remained intact. CONCLUSIONS The 5-ALA-SDT was cytotoxic toward malignant gliomas. Generation of ROS by the SDT was thought to promote apoptosis of glioma cells. The 5-ALA-SDT with HIFU induced tumor necrosis in the focus area and apoptosis in the perifocus area of the HIFU-irradiated field. These results suggest that 5-ALA-SDT with HIFU may present a less invasive and tumor-specific therapy, not only for a tumor mass but also for infiltrating tumor cells in malignant gliomas.

scholarly journals Astrocytes derived from p53-deficient mice provide a multistep in vitro model for development of malignant gliomas.

1995 ◽  
Vol 15 (8) ◽  
pp. 4249-4259 ◽  
Author(s):  
A M Yahanda ◽  
J M Bruner ◽  
L A Donehower ◽  
R S Morrison
Keyword(s):  
Genomic Instability ◽  
Malignant Transformation ◽  
Nude Mice ◽  
Malignant Gliomas ◽  
Early Event ◽  
Wild Type ◽  
Early Passage ◽  
Wild Type P53

Loss or mutation of p53 is thought to be an early event in the malignant transformation of many human astrocytic tumors. To better understand the role of p53 in their growth and transformation, we developed a model employing cultured neonatal astrocytes derived from mice deficient in one (p53 +/-) or both (p53 -/-) p53 alleles, comparing them with wild-type (p53 +/+) cells. Studies of in vitro and in vivo growth and transformation were performed, and flow cytometry and karyotyping were used to correlate changes in growth with genomic instability. Early-passage (EP) p53 -/- astrocytes achieved higher saturation densities and had more rapid growth than EP p53 +/- and +/+ cells. The EP p53 -/- cells were not transformed, as they were unable to grow in serum-free medium or in nude mice. With continued passaging, p53 -/- cells exhibited a multistep progression to a transformed phenotype. Late-passage p53 -/- cells achieved saturation densities 50 times higher than those of p53 +/+ cells and formed large, well-vascularized tumors in nude mice. p53 +/- astrocytes exhibited early loss of the remaining wild-type p53 allele and then evolved in a manner phenotypically similar to p53 -/- astrocytes. In marked contrast, astrocytes retaining both wild-type p53 alleles never exhibited a transformed phenotype and usually senesced after 7 to 10 passages. Dramatic alterations in ploidy and karyotype occurred and were restricted to cells deficient in wild-type p53 following repeated passaging. The results of these studies suggest that loss of wild-type p53 function promotes genomic instability, accelerated growth, and malignant transformation in astrocytes.

scholarly journals Tenovin-6 impairs autophagy by inhibiting autophagic flux

2017 ◽  
Vol 8 (2) ◽  
pp. e2608-e2608 ◽  
Author(s):  
Hongfeng Yuan ◽  
Brandon Tan ◽  
Shou-Jiang Gao
Keyword(s):  
Cell Types ◽  
Inhibitory Effect ◽  
Lymphocytic Leukemia ◽  
Autophagic Flux ◽  
Dependent Manner ◽  
Autophagy Pathway ◽  
Sarcoma Cells ◽  
Regulatory Functions

Abstract Tenovin-6 has attracted significant interest because it activates p53 and inhibits sirtuins. It has anti-neoplastic effects on multiple hematopoietic malignancies and solid tumors in both in vitro and in vivo studies. Tenovin-6 was recently shown to impair the autophagy pathway in chronic lymphocytic leukemia cells and pediatric soft tissue sarcoma cells. However, whether tenovin-6 has a general inhibitory effect on autophagy and whether there is any involvement with SIRT1 and p53, both of which are regulators of the autophagy pathway, remain unclear. In this study, we have demonstrated that tenovin-6 increases microtubule-associated protein 1 light chain 3 (LC3-II) level in diverse cell types in a time- and dose-dependent manner. Mechanistically, the increase of LC3-II by tenovin-6 is caused by inhibition of the classical autophagy pathway via impairing lysosomal function without affecting the fusion between autophagosomes and lysosomes. Furthermore, we have revealed that tenovin-6 activation of p53 is cell type dependent, and tenovin-6 inhibition of autophagy is not dependent on its regulatory functions on p53 and SIRT1. Our results have shown that tenovin-6 is a potent autophagy inhibitor, and raised the precaution in interpreting results where tenovin-6 is used as an inhibitor of SIRT1.

scholarly journals The human vault RNA enhances tumorigenesis and chemoresistance through the lysosome

2020 ◽  
Author(s):  
Iolanda Ferro ◽  
Jacopo Gavini ◽  
Lisamaria Bracher ◽  
Marc Landolfo ◽  
Daniel Candinas ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Tumor Cell ◽  
Chemotherapy Resistance ◽  
Autophagic Flux ◽  
Tumor Cell Proliferation ◽  
Apoptosis Resistance ◽  
Knock Out ◽  
Vault Rna

AbstractThe small non-coding vault RNA (vtRNA) 1-1 has been shown to confer apoptosis resistance in several malignant cell lines and also to modulate the autophagic flux in hepatocytes, thus highlighting its pro-survival role. Here we describe a new function of vtRNA1-1 in regulating in vitro and in vivo tumor cell proliferation, tumorigenesis and chemoresistance. By activating extracellular signal-regulated kinases (ERK 1/2), vtRNA1-1 knock-out (KO) inhibits transcription factor EB (TFEB), leading to a downregulation of the coordinated lysosomal expression and regulation (CLEAR) network genes and lysosomal compartment dysfunction. Pro-tumorigenic pathways dysregulation and decreased lysosome functionality potentiate the anticancer effect of conventional targeted cancer drugs in the absence of vtRNA1-1. Finally, vtRNA1-1 KO-reduced lysosomotropism, together with a higher intracellular compound availability, significantly reduced tumor cell proliferation in vitro and in vivo. These findings reveal the role of vtRNA1-1 in ensuring intracellular catabolic compartment stability and functionality, suggesting its importance in lysosome-mediated chemotherapy resistance.

scholarly journals Amitriptyline interferes with autophagy-mediated clearance of protein aggregates via inhibiting autophagosome maturation in neuronal cells

2020 ◽  
Vol 11 (10) ◽  
Author(s):  
Yoonjung Kwon ◽  
Yeojin Bang ◽  
Soung-Hee Moon ◽  
Aeri Kim ◽  
Hyun Jin Choi
Keyword(s):  
Neurodegenerative Diseases ◽  
Depressive Disorders ◽  
Neuronal Cells ◽  
Protein Aggregates ◽  
Underlying Mechanism ◽  
Tricyclic Antidepressant ◽  
Autophagic Flux ◽  
Autophagosome Maturation

Abstract Amitriptyline is a tricyclic antidepressant commonly prescribed for major depressive disorders, as well as depressive symptoms associated with various neurological disorders. A possible correlation between the use of tricyclic antidepressants and the occurrence of Parkinson’s disease has been reported, but its underlying mechanism remains unknown. The accumulation of misfolded protein aggregates has been suggested to cause cellular toxicity and has been implicated in the common pathogenesis of neurodegenerative diseases. Here, we examined the effect of amitriptyline on protein clearance and its relevant mechanisms in neuronal cells. Amitriptyline exacerbated the accumulation of abnormal aggregates in both in vitro neuronal cells and in vivo mice brain by interfering with the (1) formation of aggresome-like aggregates and (2) autophagy-mediated clearance of aggregates. Amitriptyline upregulated LC3B-II, but LC3B-II levels did not increase further in the presence of NH4Cl, which suggests that amitriptyline inhibited autophagic flux rather than autophagy induction. Amitriptyline interfered with the fusion of autophagosome and lysosome through the activation of PI3K/Akt/mTOR pathway and Beclin 1 acetylation, and regulated lysosome positioning by increasing the interaction between proteins Arl8, SKIP, and kinesin. To the best of our knowledge, we are the first to demonstrate that amitriptyline interferes with autophagic flux by regulating the autophagosome maturation during autophagy in neuronal cells. The present study could provide neurobiological clue for the possible correlation between the amitriptyline use and the risk of developing neurodegenerative diseases.

scholarly journals Primary Cilia Blockage Promotes the Malignant Behaviors of Hepatocellular Carcinoma via Induction of Autophagy

2019 ◽  
Vol 2019 ◽  
pp. 1-14
Author(s):  
Lian Liu ◽  
Jia-Qi Sheng ◽  
Mu-Ru Wang ◽  
Yun Gan ◽  
Xiao-Li Wu ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Primary Cilia ◽  
The Cancer Genome Atlas ◽  
Migration And Invasion ◽  
Serum Starvation ◽  
Autophagic Flux ◽  
And Function ◽  
Hcc Cells

Primary cilia are organelles protruding from cell surface into environment that function in regulating cell cycle and modulating cilia-related signal. Primary ciliogenesis and autophagy play important roles in tumorigenesis. However, the functions and interactions between primary cilia and autophagy in hepatocellular carcinoma (HCC) have not been reported yet. Here, we aimed to investigate the relationship and function of primary cilia and autophagy in HCC. In vitro, we showed that serum starvation stimuli could trigger primary ciliogenesis in HCC cells. Blockage of primary ciliogenesis by IFT88 silencing enhanced the proliferation, migration, and invasion ability of HCC cells. In addition, inhibition of primary cilia could positively regulate autophagy. However, the proliferation, migration, and invasion ability which were promoted by IFT88 silencing could be partly reversed by inhibition of autophagy. In vivo, interference of primary cilia led to acceleration of tumor growth and increase of autophagic flux in xenograft HCC mouse models. Moreover, IFT88 high expression or ATG7 low expression in HCC tissues was correlated with longer survival time indicated by the Cancer Genome Atlas (TCGA) analysis. In conclusion, our study demonstrated that blockage of primary ciliogenesis by IFT88 silencing had protumor effects through induction of autophagy in HCC. These findings define a newly recognized role of primary cilia and autophagy in HCC.

scholarly journals Myxoma Virus Infection Promotes NK Lysis of Malignant Gliomas In Vitro and In Vivo

PLoS ONE ◽  
2013 ◽  
Vol 8 (6) ◽  
pp. e66825 ◽  
Author(s):  
Henry Ogbomo ◽  
Franz J. Zemp ◽  
Xueqing Lun ◽  
Jiqing Zhang ◽  
Danuta Stack ◽  
...  
Keyword(s):  
Virus Infection ◽  
Malignant Gliomas ◽  
Myxoma Virus
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