The histone Deacetylase Inhibitor Givinostat in Combination with Sorafenib Induces Reactive Oxygen Species (ROS) Generation and Exerts Potent Antitumor Effects in NOD/SCID Mice with Hodgkin Lymphoma Cell Line Xenografts

Abstract Abstract 3711 INTRODUCTION: Patients with refractory or relapsed classical Hodgkin Lymphoma (cHL) represent an unmet medical need and would benefit from the development of new therapies. Histone deacetylases (HDACs) and the RAF/MEK/ERK pathway are aberrantly controlled in cHL and influence a broad repertoire of tumor processes, suggesting a rationale for therapeutically targeting these pathways. We targeted these pathways using the HDAC inhibitor Givinostat (Italfarmaco S.p.A., Milan, Italy), and the RAF/MEK/ERK inhibitor Sorafenib (Nexavar, Bayer, Germany, EU) in order to investigate in vitro and in vivo the activity and mechanism(s) of action of this two-drug combination. METHODS: Three cHL cell lines, including HDLM-2, L-540 and HD-MyZ, were used to investigate the effects of Givinostat and Sorafenib, used alone or in combination, by means of in vitro assays evaluating cell growth and cell survival. Additionally, live cell imaging was used to asses the production of reactive oxygen species (ROS), and Western blotting (WB) to assess modulating effects of the two-drug combination on MAPK, PI3K/AKT, HDACs as well as the apoptotic pathways. The efficacy of Givinostat/Sorafenib combination was finally confirmed in NOD/SCID mice with cHL cell line xenografts. RESULTS: While Givinostat and Sorafenib as single agents exerted a limited activity against cHL cells, the combined Givinostat/Sorafenib treatment was associated with potent dephosphorylation of MAPK and PI3K/Akt pathways and significantly increased H3 and H4 acetylation due to a nearly complete inhibition of class I and II HDACs. Furthermore, these events were associated with a time-dependent synergistic cell growth inhibition (70% to 90%) in all Givinostat/Sorafenib-treated cHL cells. Upon Givinostat/Sorafenib exposure, HDLM-2 and L-540 cell lines showed significantly (P ≤.0001) increased levels of apoptosis (90 ± 2% and 96 ± 1%, respectively) and mitochondrial dysfunction (up to 70%, P≤.0001), as compared with single agents. Apoptosis induced by Givinostat/Sorafenib combination failed to induce processing of caspase-8, −9, −3, or cleavage of PARP, and was not reversed by the pan-caspase inhibitor Z-VADfmk, suggesting the occurrence of caspase-independent apoptosis. Besides downregulating the expression of the anti-apoptotic protein Mcl-1 and ERK1/2 phosphorylation, Givinostat/Sorafenib strongly increased expression of the BH-3 only protein Bim, compared to single treatments. These findings were dependent on a potent, early and time-dependent ROS generation (up to 60%, P≤.0001) that was synergistically induced by Givinostat/Sorafenib treatment. Additionally, pretreatment of cHL cells with the ROS inhibitor YCG063 prevented the generation of ROS as well as mitochondrial membrane depolarization along with cell death induced by the two-drug combination, suggesting that ROS generation is the triggering event in Givinostat/Sorafenib induced-cell death. In vivo Givinostat/Sorafenib treatment significantly reduced the growth of L-540 and HD-MyZ nodules, resulting in an average 35% to 65% tumor growth inhibition (P ≤.0001) compared to single treatments, in the absence of any toxicity. Interestingly, as compared to controls or treatment with single agents, the combined Givinostat/Sorafenib treatment significantly increased in vivo Bim expression (7- to 21-fold increase, P ≤.0001), resulting in a marked tumor necrosis (3- to 5-fold increase, P ≤.0001). CONCLUSIONS: The combined Givinostat/Sorafenib treatment demonstrates a potent preclinical in vitro and in vivo activity against cHL cell lines by targeting aberrant expression of HDACs and MAPK. Antitumor activity of this combination involves ROS generation and Bim upregulation and provides a rationale for clinical studies using this combination in refractory/relapsed cHL patients. Disclosures: No relevant conflicts of interest to declare.

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Preclinical Rationale for the Use of the Combined Treatment with the AKT Inhibitor Perifosine and the Multikinase Inhibitor Sorafenib in Hodgkin Lymphoma

Blood ◽

10.1182/blood.v118.21.1653.1653 ◽

2011 ◽

Vol 118 (21) ◽

pp. 1653-1653

Author(s):

Silvia Locatelli ◽

Arianna Giacomini ◽

Anna Guidetti ◽

Loredana Cleris ◽

Michele Magni ◽

...

Keyword(s):

Cell Cycle ◽

Cell Growth ◽

Cell Line ◽

Cell Lines ◽

Drug Combination ◽

Akt Inhibitor ◽

Sorafenib Treatment ◽

Responsive Cell

Abstract Abstract 1653 Introduction: A significant proportion of Hodgkin lymphoma (HL) patients refractory to first-line chemotherapy or relapsing after autologous transplantation are not cured with currently available treatments and require new treatments. The PI3K/AKT and RAF/MEK/ERK pathways are constitutively activated in the majority of HL. These pathways can be targeted using the AKT inhibitor perifosine (Æterna Zentaris GmBH, Germany, EU), and the RAF/MEK/ERK inhibitor sorafenib (Nexavar®, Bayer, Germany, EU). We hypothesized that perifosine in combination with sorafenib might have a therapeutic activity in HL by overcoming the cytoprotective and anti-apoptotic effects of PI3K/Akt and RAF/MEK/ERK pathways. Since preclinical evidence supporting the anti-lymphoma effects of the perifosine/sorafenib combination are still lacking, the present study aimed at investigating in vitro and in vivo the activity and mechanism(s) of action of this two-drug combination. METHODS: Three HL cell lines (HD-MyZ, L-540 and HDLM-2) were used to investigate the effects of perifosine and sorafenib using in vitro assays analyzing cell growth, cell cycle distribution, gene expression profiling (GEP), and apoptosis. Western blotting (WB) experiments were performed to determine whether the two-drug combination affected MAPK and PI3K/AKT pathways as well as apoptosis. Additionally, the antitumor efficacy and mechanism of action of perifosine/sorafenib combination were investigated in vivo in nonobese diabetic/severe combined immune-deficient (NOD/SCID) mice. RESULTS: While perifosine and sorafenib as single agents exerted a limited activity against HL cells, exposure of HD-MyZ and L-540 cell lines, but not HDLM-2 cells, to perifosine/sorafenib combination resulted in synergistic cell growth inhibition (40% to 80%) and cell cycle arrest. Upon perifosine/sorafenib exposure, L-540 cell line showed significant levels of apoptosis (up to 70%, P ≤.0001) associated with severe mitochondrial dysfunction (cytochrome c, apoptosis-inducing factor release and marked conformational change of Bax accompanied by membrane translocation). Apoptosis induced by perifosine/sorafenib combination did not result in processing of caspase-8, -9, -3, or cleavage of PARP, and was not reversed by the pan-caspase inhibitor Z-VADfmk, supporting a caspase-independent mechanism of apoptosis. In responsive cell lines, WB analysis showed that anti-proliferative events were associated with dephosphorylation of MAPK and PI3K/Akt pathways. GEP analysis of HD-MyZ and L-540 cell lines, but not HDLM-2 cells indicated that perifosine/sorafenib treatment induced upregulation of genes involved in amino acid metabolism and downregulation of genes regulating cell cycle, DNA replication and cell death. In addition, in responsive cell lines, perifosine/sorafenib combination strikingly induced the expression of tribbles homologues 3 (TRIB3) both in vitro and in vivo. Silencing of TRIB3 prevented cell growth reduction induced by perifosine/sorafenib treatment. In vivo, the combined perifosine/sorafenib treatment significantly increased the median survival of NOD/SCID mice xenografted with HD-MyZ cell line as compared to controls (81 vs 45 days, P ≤.0001) as well as mice receiving perifosine alone (49 days, P ≤.03) or sorafenib alone (54 days, P ≤.007). In mice bearing subcutaneous nodules generated by HD-MyZ and L-540 cell lines but not HDLM-2 cell line, perifosine/sorafenib treatment induced significantly increased levels of apoptosis (2- to 2.5-fold, P ≤.0001) and necrosis (2- to 8-fold, P ≤.0001), as compared to controls or treatment with single agents. CONCLUSIONS: Perifosine/sorafenib combination resulted in potent anti-HL activity both in vitro and in vivo. These results warrant clinical evaluation in HL patients. Disclosures: No relevant conflicts of interest to declare.

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β-Adrenergic signaling stimulates osteoclastogenesis via reactive oxygen species

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00191.2012 ◽

2013 ◽

Vol 304 (5) ◽

pp. E507-E515 ◽

Cited By ~ 34

Author(s):

Hisataka Kondo ◽

Shoko Takeuchi ◽

Akifumi Togari

Keyword(s):

Reactive Oxygen Species ◽

Raw 264.7 Cells ◽

Ros Generation ◽

Raw 264.7 ◽

Nuclear Factor ◽

Oxygen Species ◽

Adrenergic Signaling ◽

Intracellular Ros

Sympathetic signaling regulates bone resorption through receptor activator of nuclear factor-κB ligand (RANKL) expression via the β-adrenergic receptor (β-AR) on osteoblasts. Reactive oxygen species (ROS) are known as one type of osteoclast regulatory molecule. Here we show that an antioxidant, α-lipoic acid (α-LA), treatment prevent the β-adrenergic signaling-induced bone loss by suppressing osteoclastogenesis, and sympathetic signaling directly regulates osteoclastogenesis through β2-AR expressed on osteoclasts via intracellular ROS generation. In an in vitro study, the β-AR agonist isoprenaline increased intracellular ROS generation in osteoclasts prepared from bone marrow macrophages (BBMs) and RAW 264.7 cells. Isoprenaline enhanced osteoclastogenesis through β2-AR expressed on BMMs and RAW 264.7 cells. The antioxidant α-LA inhibited isoprenaline-enhanced osteoclastogenesis. Isoprenaline increased the expression of osteoclast-related genes such as nuclear factor of activated T cells, cytoplasmic, calcineurin-dependent 1, tartrate-resistant acid phosphatase, and cathepsin K on osteoclasts. α-LA also inhibited isoprenaline-induced increases of these gene expressions. These in vitro results led to the hypothesis that β-adrenergic signaling directly stimulates osteoclastogenesis via ROS generation. In an in vivo study, isoprenaline treatment alone caused oxidative damage in local bone and reduced bone mass because of an increase in bone resorption, and, in α-LA-treated mice, isoprenaline did not increase tibial osteoclast number even though the RANKL-to-osteoprotegerin ratio increased. These in vitro and in vivo results indicate that β-adrenergic signaling, at least in part, directly stimulates osteoclastogenesis through β2-AR on osteoclasts via ROS generation.

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The PI3K/ERK Dual Inhibitor AEZS-136 Induces ROS-Dependent Necroptotic Cell Death and Exerts Potent Antitumor Effects In NOD/SCID Mice With Hodgkin Lymphoma Cell Line Xenografts

Blood ◽

10.1182/blood.v122.21.3067.3067 ◽

2013 ◽

Vol 122 (21) ◽

pp. 3067-3067

Author(s):

Silvia L Locatelli ◽

Giuliano G Stirparo ◽

Silvia Tartari ◽

Elena Saba ◽

Luca Rubino ◽

...

Keyword(s):

Cell Death ◽

Cell Lines ◽

S Phase ◽

Scid Mice ◽

Ros Generation ◽

Oxygen Species ◽

Dual Inhibitor ◽

Dose Dependent

Abstract Introduction Disease relapse and resistance to chemotherapy represent challenging issues for Hodgkin Lymphoma (HL) patients. PI3K/AKT and RAF/MEK/ERK pathways are constitutively activated in the majority of HL patients, thus representing attractive therapeutic targets. Previous results from our phase II study indicate that combining the PI3K/AKT inhibitor perifosine with the RAF/MEK/ERK inhibitor sorafenib can achieve significant clinical responses in relapsed/refractory HL. The present study was therefore aimed at characterizing the in vitro and in vivo activity and mechanism(s) of action of a novel PI3K/ERK dual inhibitor AEZS-136 (Æterna Zentaris GmbH, Germany, EU). Methods Four HL cell lines (L-540, SUP-HD1, KM-H2 and L-428) were used to investigate the in vitro effects of AEZS-136 on cell growth, cell cycle distribution, gene expression profiling (GEP), and apoptosis. Live cell imaging experiments were performed to asses the production of reactive oxygen species (ROS). Western blotting (WB) was used to assess the effects of AEZS-136 on MAPK and PI3K/AKT pathways as well as apoptosis. The antitumor efficacy of AEZS-136 was investigated in vivo in nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice. Results Exposure of L-540, SUP-HD1, KM-H2 and L-428 cell lines to AEZS-136 induced a marked, early and time-dependent dephosphorylation of PI3K/Akt and MAPK pathways that was associated with a significant time and dose-dependent cell growth inhibition [80 ± 3% (mean ±SEM) in the L-540 and SUP-HD1 responsive cell lines] and S phase cell cycle arrest. Indeed, upon AEZS-136 treatment the mean (±SEM) percentages of cells in S phase were reduced by 3-fold (13 ± 1%) as compared to control (33 ± 2%). Significant levels of cell death, as assessed by AnnexinV/PI staining, were only observed in L-540 (62 ± 9 vs 14 ± 3%, P ≤.0001) and SUP-HD1 (46 ± 2% vs 15 ± 2%, P ≤.0001) cell lines and were associated with severe mitochondrial dysfunction (up to 40%, P ≤.001). While no activation of caspase-3 and PARP cleavage were observed in L-540 and SUP-HD1 cells treated with AEZS-136, a potent generation of reactive oxygen species (ROS) was observed upon AEZS-136 treatment (up to 90%, P≤.0001). Pretreating cells with the ROS inhibitor YCG063 strongly inhibited AEZS-136-induced ROS generation, mitochondrial dysfunction and cell death, whereas the pan-caspase inhibitor Z-VADfmk did not. Since ROS generation has been implicated in mediating necroptosis, we tested if blocking programmed necrosis with Necrostatin-1 could prevent AEZS-136-induced cytotoxicity. When L-540 cells were treated with AEZS-136 in the presence of Necrostatin-1, cell death and ROS generation were completely prevented, suggesting that cell death was mechanistically related to necroptosis. Additionally, HL cells responsive to AEZS-136-induced cell death showed a pronounced JNK activation whose inhibition by the JNK inhibitor SP600125 reduced cell death and ROS generation. Furthermore, AEZS-136-increased JNK phosphorylation was inhibited by Necrostatin-1 or YCG063, suggesting that ROS-dependent necroptosis was linked to JNK. Interestingly, GEP analysis of L-540 and SUP-HD1 cell lines, but not KM-H2 and L-428 cells, indicated that AEZS-136 treatment induced upregulation of genes involved in positive regulation of cell death. In addition, in KM-H2 and L-428 cells, AEZS-136 strikingly induced the expression of the immediate early response 3 (IER3). Silencing of IER3 restored sensitivity of KM-H2 and L-428 cells to AEZS-136-induced necroptotic cell death, suggesting that IER3 acts as the signaling molecule that mediated AEZS-136-resistance to oxidative cell death. Finally, in vivo experiments were conducted to investigate the antitumor activity of AEZS-136. Treatment of NOD/SCID mice bearing L540 tumor nodules with increasing dose of AEZS-136 (30 – 60 mg/Kg body weight, PO, 5 days/2 weeks) resulted in a dose-dependent reduction of tumor growth (mean TGI of 70%, P ≤.0001) compared to vehicle-treated controls. No mice experienced any apparent treatment-related toxicity. Conclusions The PI3K/ERK dual inhibitor AEZS-136 demonstrates a potent antitumor activity against HL cell lines by targeting aberrant expression of MAPK and PI3K/Akt pathways. These data support further clinical evaluation of AEZS-136 in refractory/relapsed HL patients. Disclosures: No relevant conflicts of interest to declare.

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Ghrelin Ameliorates Diabetic Retinal Injury: Potential Therapeutic Avenues for Diabetic Retinopathy

Oxidative Medicine and Cellular Longevity ◽

10.1155/2021/8043299 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Jie Bai ◽

Fan Yang ◽

Ruiqi Wang ◽

Qinghui Yan

Keyword(s):

Reactive Oxygen Species ◽

Diabetic Retinopathy ◽

Cell Damage ◽

Reactive Oxygen ◽

Diabetic Rats ◽

Enzyme Linked Immunosorbent Assay ◽

Ros Generation ◽

Oxygen Species

Ghrelin has anti-inflammatory, antioxidant, and antiapoptotic effects, and it may be beneficial for the treatment of many ophthalmic diseases, such as cataract, uveitis, and glaucoma. Our previous work proved that ghrelin pretreatment reduced the apoptosis of lens epithelial cells induced by hydrogen peroxide, reduced the accumulation of reactive oxygen species (ROS), and effectively maintained the transparency of lens tissue. However, no study has yet investigated the effect of ghrelin on retina. In this study, we conducted in vitro and in vivo experiments to explore the effect of ghrelin on high-glucose- (HG-) induced ARPE-19 cell damage and diabetic retinopathy in streptozotocin-induced diabetic rats. ARPE-19 cells were incubated in a normal or an HG (30 mM glucose) medium with or without ghrelin. Cell viability was measured by 3-(4, 5-dimethylthiazol-3-yl)-2,5-diphenyl tetrazolium bromide assay, and apoptosis was detected by the Hoechst–PI staining assay. Intracellular reactive oxygen species (ROS) production levels within cells were measured using 2 ′ ,7 ′ -dichlorofluorescein diacetate staining, and the contents of superoxide dismutase and malondialdehyde were measured using relevant detection kits. The expression levels of IL-1β and IL-18 were measured using an enzyme-linked immunosorbent assay, and those of NLRP3, IL-1β, and IL-18 were measured using Western blotting. The rat diabetes models were induced using a single intraperitoneal injection of streptozotocin (80 mg/kg). The morphological and histopathological changes in the retinal tissues were examined. The results indicated that ghrelin reduced ROS generation, inhibited cell apoptosis and the activation of NLRP3 inflammasome, inhibited the apoptosis of retinal cells in diabetic rats, and protected the retina against HG-induced dysfunction. In conclusion, ghrelin may play a role in the treatment of ocular diseases involving diabetic retinopathy.

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Modulation of reactive oxygen species by Rac1 or catalase prevents asbestos-induced pulmonary fibrosis

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.90590.2008 ◽

2009 ◽

Vol 297 (5) ◽

pp. L846-L855 ◽

Cited By ~ 51

Author(s):

Shubha Murthy ◽

Andrea Adamcakova-Dodd ◽

Sarah S. Perry ◽

Linda A. Tephly ◽

Richard M. Keller ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Pulmonary Fibrosis ◽

Alveolar Macrophages ◽

Reactive Oxygen ◽

Ros Generation ◽

Dependent Manner ◽

Oxygen Species ◽

Tnf Α

The release of reactive oxygen species (ROS) and cytokines by alveolar macrophages has been demonstrated in asbestos-induced pulmonary fibrosis, but the mechanism linking alveolar macrophages to the pathogenesis is not known. The GTPase Rac1 is a second messenger that plays an important role in host defense. In this study, we demonstrate that Rac1 null mice are protected from asbestos-induced pulmonary fibrosis, as determined by histological and biochemical analysis. We hypothesized that Rac1 induced pulmonary fibrosis via generation of ROS. Asbestos increased TNF-α and ROS in a Rac1-dependent manner. TNF-α was elevated only 1 day after exposure, whereas ROS generation progressively increased in bronchoalveolar lavage cells obtained from wild-type (WT) mice. To determine whether ROS generation contributed to pulmonary fibrosis, we overexpressed catalase in WT monocytes and observed a decrease in ROS generation in vitro . More importantly, administration of catalase to WT mice attenuated the development of fibrosis in vivo. For the first time, these results demonstrate that Rac1 plays a crucial role in asbestos-induced pulmonary fibrosis. Moreover, it suggests that a simple intervention may be useful to prevent progression of the disease.

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Targeting autophagy enhances atezolizumab-induced mitochondria-related apoptosis in osteosarcoma

Cell Death and Disease ◽

10.1038/s41419-021-03449-6 ◽

2021 ◽

Vol 12 (2) ◽

Author(s):

Zhuochao Liu ◽

Hongyi Wang ◽

Chuanzhen Hu ◽

Chuanlong Wu ◽

Jun Wang ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Antitumor Immunity ◽

Reactive Oxygen ◽

Oxygen Species ◽

Specific Monoclonal Antibody ◽

Osteosarcoma Cells ◽

Jnk Pathway ◽

In Vivo Experiments

AbstractIn this study, we identified the multifaceted effects of atezolizumab, a specific monoclonal antibody against PD-L1, in tumor suppression except for restoring antitumor immunity, and investigated the promising ways to improve its efficacy. Atezolizumab could inhibit the proliferation and induce immune-independent apoptosis of osteosarcoma cells. With further exploration, we found that atezolizumab could impair mitochondria of osteosarcoma cells, resulting in increased release of reactive oxygen species and cytochrome-c, eventually leading to mitochondrial-related apoptosis via activating JNK pathway. Nevertheless, the excessive release of reactive oxygen species also activated the protective autophagy of osteosarcoma cells. Therefore, when we combined atezolizumab with autophagy inhibitors, the cytotoxic effect of atezolizumab on osteosarcoma cells was significantly enhanced in vitro. Further in vivo experiments also confirmed that atezolizumab combined with chloroquine achieved the most significant antitumor effect. Taken together, our study indicates that atezolizumab can induce mitochondrial-related apoptosis and protective autophagy independently of the immune system, and targeting autophagy is a promising combinatorial approach to amplify its cytotoxicity.

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Plant Extracts and Reactive Oxygen Species as Two Counteracting Agents with Anti- and Pro-Obesity Properties

International Journal of Molecular Sciences ◽

10.3390/ijms20184556 ◽

2019 ◽

Vol 20 (18) ◽

pp. 4556 ◽

Cited By ~ 6

Author(s):

Hanna Zielinska-Blizniewska ◽

Przemyslaw Sitarek ◽

Anna Merecz-Sadowska ◽

Katarzyna Malinowska ◽

Karolina Zajdel ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Plant Extracts ◽

Complex Disease ◽

Reactive Oxygen ◽

Complementary Therapy ◽

Biologically Active ◽

Mitochondrial Activity ◽

Oxygen Species

Obesity is a complex disease of great public health significance worldwide: It entails several complications including diabetes mellitus type 2, cardiovascular dysfunction and hypertension, and its prevalence is increasing around the world. The pathogenesis of obesity is closely related to reactive oxygen species. The role of reactive oxygen species as regulatory factors in mitochondrial activity in obese subjects, molecules taking part in inflammation processes linked to excessive size and number of adipocytes, and as agents governing the energy balance in hypothalamus neurons has been examined. Phytotherapy is the traditional form of treating health problems using plant-derived medications. Some plant extracts are known to act as anti-obesity agents and have been screened in in vitro models based on the inhibition of lipid accumulation in 3T3-L1 cells and activity of pancreatic lipase methods and in in vivo high-fat diet-induced obesity rat/mouse models and human models. Plant products may be a good natural alternative for weight management and a source of numerous biologically-active chemicals, including antioxidant polyphenols that can counteract the oxidative stress associated with obesity. This review presents polyphenols as natural complementary therapy, and a good nutritional strategy, for treating obesity without serious side effects.

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Effects of Ubiquinol-10 on MicroRNA-146a Expression In Vitro and In Vivo

Mediators of Inflammation ◽

10.1155/2009/415437 ◽

2009 ◽

Vol 2009 ◽

pp. 1-7 ◽

Cited By ~ 24

Author(s):

Constance Schmelzer ◽

Mitsuaki Kitano ◽

Gerald Rimbach ◽

Petra Niklowitz ◽

Thomas Menke ◽

...

Keyword(s):

Gene Expression ◽

Reactive Oxygen Species ◽

Biological Processes ◽

Oxygen Species ◽

Moderate Reduction ◽

Suppression Of Gene Expression ◽

Fine Tune ◽

Dependent Pathway

MicroRNAs (miRs) are involved in key biological processes via suppression of gene expression at posttranscriptional levels. According to their superior functions, subtle modulation of miR expression by certain compounds or nutrients is desirable under particular conditions. Bacterial lipopolysaccharide (LPS) induces a reactive oxygen species-/NF-κB-dependent pathway which increases the expression of the anti-inflammatory miR-146a. We hypothesized that this induction could be modulated by the antioxidant ubiquinol-10. Preincubation of human monocytic THP-1 cells with ubiquinol-10 reduced the LPS-induced expression level of miR-146a to 78.9±13.22%. In liver samples of mice injected with LPS, supplementation with ubiquinol-10 leads to a reduction of LPS-induced miR-146a expression to 78.12±21.25%. From these consistent in vitro and in vivo data, we conclude that ubiquinol-10 may fine-tune the inflammatory response via moderate reduction of miR-146a expression.

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A Novel Tetrapeptide Derivative Exhibits In Vitro Inhibition of Neutrophil-Derived Reactive Oxygen Species and Lysosomal Enzymes Release

Oxidative Medicine and Cellular Longevity ◽

10.1155/2013/853210 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

Sumitra Miriyala ◽

Manikandan Panchatcharam ◽

Meera Ramanujam ◽

Rengarajulu Puvanakrishnan

Keyword(s):

Reactive Oxygen Species ◽

Superoxide Anion ◽

Lysosomal Enzymes ◽

Reactive Oxygen ◽

Peptide Sequence ◽

Ros Generation ◽

Oxygen Species ◽

Complement Factors

Neutrophil infiltration plays a major role in the pathogenesis of myocardial injury. Oxidative injury is suggested to be a central mechanism of the cellular damage after acute myocardial infarction. This study is pertained to the prognostic role of a tetrapeptide derivative PEP1261 (BOC-Lys(BOC)-Arg-Asp-Ser(tBu)-OtBU), a peptide sequence (39–42) of lactoferrin, studied in the modulation of neutrophil functions in vitro by measuring the reactive oxygen species (ROS) generation, lysosomal enzymes release, and enhanced expression of C proteins. The groundwork experimentation was concerned with the isolation of neutrophils from the normal and acute myocardial infarct rats to find out the efficacy of PEP1261 in the presence of a powerful neutrophil stimulant, phorbol 12-myristate 13 acetate (PMA). Stimulation of neutrophils with PMA resulted in an oxidative burst of superoxide anion and enhanced release of lysosomal enzymes and expression of complement proteins. The present study further demonstrated that the free radicals increase the complement factors in the neutrophils confirming the role of ROS. PEP1261 treatment significantly reduced the levels of superoxide anion and inhibited the release of lysosomal enzymes in the stimulated control and infarct rat neutrophils. This study demonstrated that PEP1261 significantly inhibited the effect on the ROS generation as well as the mRNA synthesis and expression of the complement factors in neutrophils isolated from infarct heart.

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