scholarly journals Acetaldehyde accelerates HCV-induced impairment of innate immunity by suppressing methylation reactions in liver cells

2015 ◽  
Vol 309 (7) ◽  
pp. G566-G577 ◽  
Author(s):  
Murali Ganesan ◽  
Jinjin Zhang ◽  
Tatiana Bronich ◽  
Larisa I. Poluektova ◽  
Terrence M. Donohue ◽  
...  

Alcohol exposure worsens the course and outcomes of hepatitis C virus (HCV) infection. Activation of protective antiviral genes is induced by IFN-α signaling, which is altered in liver cells by either HCV or ethanol exposure. However, the mechanisms of the combined effects of HCV and ethanol metabolism in IFN-α signaling modulation are not well elucidated. Here, we explored a possibility that ethanol metabolism potentiates HCV-mediated dysregulation of IFN-α signaling in liver cells via impairment of methylation reactions. HCV-infected Huh7.5 CYP2E1+ cells and human hepatocytes were exposed to acetaldehyde (Ach)-generating system (AGS) and stimulated with IFN-α to activate IFN-sensitive genes (ISG) via the Jak-STAT-1 pathway. We observed significant suppression of signaling events by Ach. Ach exposure decreased STAT-1 methylation via activation of protein phosphatase 2A and increased the protein inhibitor of activated STAT-1 (PIAS-1)-STAT-1 complex formation in both HCV+ and HCV− cells, preventing ISG activation. Treatment with a promethylating agent, betaine, attenuated all examined Ach-induced defects. Ethanol metabolism-induced changes in ISGs are methylation related and confirmed by in vivo studies on HCV+ transgenic mice. HCV- and Ach-induced impairment of IFN signaling temporarily increased HCV RNA levels followed by apoptosis of heavily infected cells. We concluded that Ach potentiates the suppressive effects of HCV on activation of ISGs attributable to methylation-dependent dysregulation of IFN-α signaling. A temporary increase in HCV RNA sensitizes the liver cells to Ach-induced apoptosis. Betaine reverses the inhibitory effects of Ach on IFN signaling and thus can be used for treatment of HCV+ alcohol-abusing patients.

2019 ◽  
Vol 10 (4) ◽  
pp. 437-447 ◽  
Author(s):  
D.R. Michael ◽  
T.S. Davies ◽  
K.E. Loxley ◽  
M.D. Allen ◽  
M.A. Good ◽  
...  

Neurodegeneration has been linked to changes in the gut microbiota and this study compares the neuroprotective capability of two bacterial consortia, known as Lab4 and Lab4b, using the established SH-SY5Y neuronal cell model. Firstly, varying total antioxidant capacities (TAC) were identified in the intact cells from each consortia and their secreted metabolites, referred to as conditioned media (CM). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and Crystal Violet (CV) assays of cell viability revealed that Lab4 CM and Lab4b CM could induce similar levels of proliferation in SH-SY5Y cells and, despite divergent TAC, possessed a comparable ability to protect undifferentiated and retinoic acid-differentiated cells from the cytotoxic actions of rotenone and undifferentiated cells from the cytotoxic actions of 1-methyl-4-phenylpyridinium iodide (MPP+). Lab4 CM and Lab4b CM also had the ability to attenuate rotenone-induced apoptosis and necrosis with Lab4b inducing the greater effect. Both consortia showed an analogous ability to attenuate intracellular reactive oxygen species accumulation in SH-SY5Y cells although the differential upregulation of genes encoding glutathione reductase and superoxide dismutase by Lab4 CM and Lab4b CM, respectively, implicates the involvement of consortia-specific antioxidative mechanisms of action. This study implicates Lab4 and Lab4b as potential neuroprotective agents and justifies their inclusion in further in vivo studies.


2019 ◽  
Vol 20 (22) ◽  
pp. 5567
Author(s):  
Jan Torben Schille ◽  
Ingo Nolte ◽  
Eva-Maria Packeiser ◽  
Laura Wiesner ◽  
Jens Ingo Hein ◽  
...  

Current therapies are insufficient for metastatic prostate cancer (PCa) in men and dogs. As human castrate-resistant PCa shares several characteristics with the canine disease, comparative evaluation of novel therapeutic agents is of considerable value for both species. Novel isoquinolinamine FX-9 exhibits antiproliferative activity in acute lymphoblastic leukemia cell lines but has not been tested yet on any solid neoplasia type. In this study, FX-9′s mediated effects were characterized on two human (PC-3, LNCaP) and two canine (CT1258, 0846) PCa cell lines, as well as benign solid tissue cells. FX-9 significantly inhibited cell viability and induced apoptosis with concentrations in the low micromolar range. Mediated effects were highly comparable between the PCa cell lines of both species, but less pronounced on non-malignant chondrocytes and fibroblasts. Interestingly, FX-9 exposure also leads to the formation and survival of enlarged multinucleated cells through mitotic slippage. Based on the results, FX-9 acts as an anti-mitotic agent with reduced cytotoxic activity in benign cells. The characterization of FX-9-induced effects on PCa cells provides a basis for in vivo studies with the potential of valuable transferable findings to the benefit of men and dogs.


Blood ◽  
2009 ◽  
Vol 114 (9) ◽  
pp. 1987-1998 ◽  
Author(s):  
Tong-Young Lee ◽  
Stefan Muschal ◽  
Elke A. Pravda ◽  
Judah Folkman ◽  
Amir Abdollahi ◽  
...  

Angiostatin, a proteolytic fragment of plasminogen, is a potent endogenous antiangiogenic agent. The molecular mechanisms governing angiostatin's antiangiogenic and antitumor effects are not well understood. Here, we report the identification of mitochondrial compartment as the ultimate target of angiostatin. After internalization of angiostatin into the cell, at least 2 proteins within the mitochondria bind this molecule: malate dehydrogenase, a member of Krebs cycle, and adenosine triphosphate synthase. In vitro and in vivo studies revealed differential regulation of key prosurvival and angiogenesis-related proteins in angiostatin-treated tumors and tumor-endothelium. Angiostatin induced apoptosis via down-regulation of mitochondrial BCL-2. Angiostatin treatment led to down-regulation of c-Myc and elevated levels of another key antiangiogenic protein, thrombospondin-1, reinforcing its antitumor and antiangiogenic effects. Further evidence is provided for reduced recruitment and infiltration of bone marrow–derived macrophages in angiostatin-treated tumors. The observed effects of angiostatin were restricted to the tumor site and were not observed in other major organs of the mice, indicating unique tumor specific bioavailability. Together, our data suggest mitochondria as a novel target for antiangiogenic therapy and provide mechanistic insights to the antiangiogenic and antitumor effects of angiostatin.


2013 ◽  
Vol 2013 ◽  
pp. 1-17 ◽  
Author(s):  
M. Gokila Vani ◽  
K. J. Senthil Kumar ◽  
Jiunn-Wang Liao ◽  
Shih-Chang Chien ◽  
Jeng-Leun Mau ◽  
...  

In this study, we investigated the cytoprotective effects of antcin C, a steroid-like compound isolated from Antrodia cinnamaomea against AAPH-induced oxidative stress and apoptosis in human hepatic HepG2 cells. Pretreatment with antcin C significantly protects hepatic cells from AAPH-induced cell death through the inhibition of ROS generation. Furthermore, AAPH-induced lipid peroxidation, ALT/AST secretion and GSH depletion was significantly inhibited by antcin C. The antioxidant potential of antcin C was correlated with induction of antioxidant genes including, HO-1, NQO-1,γ-GCLC, and SODviatranscriptional activation of Nrf2. The Nrf2 activation by antcin C is mediated by JNK1/2 and PI3K activation, whereas pharmacologic inhibition of JNK1/2 and PI3K abolished antcin C-induced Nrf2 activity. In addition, AAPH-induced apoptosis was significantly inhibited by antcin C through the down-regulation of pro-apoptotic factors including, Bax, cytochrome c, capase 9, -4, -12, -3, and PARP.In vivostudies also show that antcin C significantly protected mice liver from AAPH-induced hepatic injury as evidenced by reduction in hepatic enzymes in circulation. Further, immunocytochemistry analyses showed that antcin C significantly increased HO-1 and Nrf2 expression in mice liver tissues. These results strongly suggest that antcin C could protect liver cells from oxidative stress and cell deathviaNrf2/ARE activation.


2019 ◽  
Vol 20 (20) ◽  
pp. 5238 ◽  
Author(s):  
Daniela Maria Tanase ◽  
Evelina Maria Gosav ◽  
Smaranda Radu ◽  
Claudia Florida Costea ◽  
Manuela Ciocoiu ◽  
...  

Acute kidney injury (AKI) following platinum-based chemotherapeutics is a frequently reported serious side-effect. However, there are no approved biomarkers that can properly identify proximal tubular injury while routine assessments such as serum creatinine lack sensitivity. Kidney-injury-molecule 1 (KIM-1) is showing promise in identifying cisplatin-induced renal injury both in vitro and in vivo studies. In this review, we focus on describing the mechanisms of renal tubular cells cisplatin-induced apoptosis, the associated inflammatory response and oxidative stress and the role of KIM-1 as a possible biomarker used to predict cisplatin associated AKI.


2001 ◽  
Vol 29 (3) ◽  
pp. 251-257 ◽  
Author(s):  
Helmut Segner ◽  
Jean-Pierre Cravedi

In aquatic toxicology, isolated liver cells from fish can be used as a tool to generate initial information on the hepatic metabolism of xenobiotics, and on the mechanisms of xenobiotic activation or deactivation. This isolation of teleost liver cells is achieved by enzymic dissociation, and monolayer cultures of fish hepatocytes in serum-free medium maintain good viability for 3–8 days. During in vitro culture, fish liver cells express stable levels of phase I and phase II enzymes, such as cytochrome P4501A or glutathione S-transferase, and the cells show an induction of biotransformation enzymes after exposure to xenobiotics. The xenobiotic metabolite pattern produced by fish hepatocytes in vitro is generally similar to that observed in vivo. Limitations to more-intensive application of cultured fish hepatocytes as a screen in aquatic hazard assessment are partly due to the rather limited scope of existing studies, i.e. the focus on one particular species (rainbow trout), and on one particular biotransformation enzyme (cytochrome P4501A), as well as a lack of comparative in vitro/in vivo studies.


2018 ◽  
Vol 24 (24) ◽  
pp. 2760-2764 ◽  
Author(s):  
Chenxing Fu ◽  
Guiping Guan ◽  
Hongbing Wang

In vitro and in vivo studies have revealed that Sanguinarine has antioxidant, anti-inflammatory, proapoptotic, and growth inhibitory effects on tumor cells of a variety of cancers. Previous research showed that sanguinarine induced apoptosis (cell death) and/or antiproliferative while reducing tumor cell antiangiogenic and anti-invasive properties. This paper describes various sanguinarine anti-cancer mechanisms, including inhibition of erroneously-activated signal transduction pathways, apoptosis, and tumor cell proliferation inhibition.


2012 ◽  
Vol 30 (5_suppl) ◽  
pp. 61-61
Author(s):  
Farshid Dayyani ◽  
Nila Parikh ◽  
Jian H. Song ◽  
John C. Araujo ◽  
Joan M. Carboni ◽  
...  

61 Background: The Src and IGF-1R axes are aberrantly activated in both PCa and the microenvironment of bone metastases. Dasatinib and BMS-754807 are clinically promising small molecule inhibitors with high potency against Src family kinases (SFK) and IR/IGF-1R, respectively. Based on a phase I/II clinical trial in which 9/19 pts treated with docetaxel + dasatinib were increased in serum IGF-1 levels after one cycle, the aim of this study was to establish potential antitumor cooperativity of inhibiting both IGF-1R and Src in experimental PCa models in vitro and in mice. Methods: Inhibition of Src and IGF-1R pathways was accomplished by pharmacologic agents (dasatinib against Src and BMS-754807 against IR/IGF-1R) as well as by shRNA, in PC3 and LNCaP cells. In vivo studies were done after orthotopic and intratibial injection of PC3 cells in nude mice. Results: SFK inhibition decreased proliferation and migration of PCa cells whereas IGF-1R blockade induced apoptosis. All anti-tumor effects were enhanced by dual blockade. IGF-1 induced phosphorylation of Akt1 and 2. Only Akt 1 phosphorylation was decreased by dasatinib; whereas Akt 1 and 2 phosphorylation were completely abrogated by the combination. Dasatinib and BMS-754807 inhibited orthotopic in vivo tumor growth of PC3 cells more potently than either inhibitor alone. Similarly, intratibial tumor growth and bone destruction was significantly reduced with the drug combination, accompanied by a decrease in serum bone turnover markers alkaline phosphatase and N-telopeptide. Conclusions: Dual inhibition of Src and IGF-1R has greater anti-tumor effect in PCa cells compared to inhibiting either alone. In the presence of IGF-1, dasatinib and BMS-754807 are necessary to inhibit IGF-1-induced phosphorylation of Akt1 and 2 in tumor cells in culture. In intratibial models, decreased bone turnover markers in serum support the concept of targeting both the epithelial and bone microenvironment. The combination of dasatinib and BMS-754807 may be a rational therapeutic approach in PCa by blocking complementary processes of tumor growth and progression.


Gut ◽  
2021 ◽  
pp. gutjnl-2020-321175
Author(s):  
Shumei Song ◽  
Qiongrong Chen ◽  
Yuan Li ◽  
Guang Lei ◽  
Ailing Scott ◽  
...  

ObjectiveGastro-oesophageal cancers (GEC) are resistant to therapy and lead to poor prognosis. The cancer stem cells (CSCs) and antiapoptotic pathways often confer therapy resistance. We sought to elucidate the antitumour action of a BCL-2 inhibitor, AT101 in GEC in vitro, in vivo and in a clinical trial.MethodsExtensive preclinical studies in vitro and in vivo were carried out to establish the mechanism action of AT101 on targeting CSCs and antiapoptotic proteins. A pilot clinical trial in patients with GEC was completed with AT-101 added to standard chemoradiation.ResultsOverexpression of BCL-2 and MCL-1 was noted in gastric cancer tissues (GC). AT-101 induced apoptosis, reduced proliferation and tumour sphere formation in MCL-1/BCL-2 high GC cells. Interestingly, AT101 dramatically downregulated genes (YAP-1/Sox9) that control CSCs in GEC cell lines regardless of BCL-2/MCL-1 expression. Addition of docetaxel to AT-101 amplified its antiproliferation and induced apoptosis effects. In vivo studies confirmed the combination of AT101 and docetaxel demonstrated stronger antitumour activity accompanied with significant decrease of CSCs biomarkers (YAP1/SOX9). In a pilot clinical trial, 13 patients with oesophageal cancer (EC) received AT101 orally concurrently with chemoradiation. We observed dramatic clinical complete responses and encouraging overall survival in these patients. Clinical specimen analyses revealed that AT-101 dramatically reduced the expression of CSCs genes in treated EC specimens indicating antitumour activity of AT101 relies more on its anti-CSCs activity.ConclusionsOur preclinical and clinical data suggest that AT-101 overcomes resistance by targeting CSCs pathways suggesting a novel mechanism of action of AT101 in patients with GEC.


Sign in / Sign up

Export Citation Format

Share Document