Protection of ATP-depleted cells by impermeant strychnine derivatives: implications for glycine cytoprotection.

PubMed

Dong, Z; Venkatachalam, M A; Weinberg, J M; Saikumar, P; Patel, Y

2001-03-01

Glycine and structurally related amino acids with activities at chloride channel receptors in the central nervous system also have robust protective effects against cell injury by ATP depletion. The glycine receptor antagonist strychnine shares this protective activity. An essential step toward identification of the molecular targets for these compounds is to determine whether they protect cells through interactions with intracellular targets or with molecules on the outer surface of plasma membranes. Here we report cytoprotection by a cell-impermeant derivative of strychnine. A strychnine-fluorescein conjugate (SF) was synthesized, and impermeability of plasma membranes to this compound was verified by fluorescence confocal microscopy. In an injury model of Madin-Darby canine kidney cells, ATP depletion led to lactate dehydrogenase release. SF prevented lactate dehydrogenase leakage without ameliorating ATP depletion. This was accompanied by preservation of cellular ultrastructure and exclusion of vital dyes. SF protection was also shown for ATP-depleted rat hepatocytes. On the other hand, when a key structural motif in the active site of strychnine was chemically blocked, the SF lost its protective effect, establishing strychnine-related specificity for SF protection. Cytoprotective effects of the cell-impermeant strychnine derivative provide compelling evidence suggesting that molecular targets on the outer surface of plasma membranes may mediate cytoprotection by strychnine and glycine.

[Protective effect and mechanism of compound Ginkgo biloba granules on oxidative stress injury of HUVEC].

PubMed

Li, Qi; Chen, Xi; Kan, Xiao-Xi; Li, Yu-Jie; Yang, Qing; Wang, Ya-Jie; Chen, Ying; Weng, Xiao-Gang; Cai, Wei-Yan; Huang, He-Fei; Zhu, Xiao-Xin

2016-02-01

To reveal the protective and anti-apoptosis effect of compound Ginkgo biloba granules on oxidative stress injury of human umbilical vein endothelial cells (HUVEC). Negative control group, H2O2 model group and 4 drug pretreatment groups (80, 160, 320, 640 mg• L⁻¹) were established. The cell proliferation, morphological changes in each group after oxidative stress injury was detected by MTT assay and through microscope observation respectively. The content of LDH, MDA, SOD and NO and SOD activity in supernatant were detected to judge the protection effect of the drugs on endothelial cells. The protective effect on HUVEC apoptosis was analyzed by Caspase-3 activity test and Annexin V-FITC/PI staining. Western blot was used to observe the expression of apoptosis-related proteins Bcl-2 and Bax. Results showed that 1 200 μmol• L⁻¹ H2O2 can induce oxidative stress injury in endothelial cells and reduce the cell survival rate; cell proliferation inhibition degree is positively correlated with the effect time of H2O2. Besides, 80, 160, 320 640 mg•L⁻¹ compound Ginkgo biloba granules can protect HUVEC from oxidative stress injury, recover the normal proliferation level of cells, improve their state, prohibit cell apoptosis, and can up-regulate and down-regulate the expression level of Bcl-2 and Bax respectively. In conclusion, compound G. biloba granules can protect HUVEC from the oxidative stress injury induced by H2O2, its mechanism may be correlated with inhibition of the mitochondrial apoptotic pathway in HUVEC. Copyright© by the Chinese Pharmaceutical Association.

Apigenin attenuates streptozotocin-induced pancreatic β cell damage by its protective effects on cellular antioxidant defense.

PubMed

Wang, Ning; Yi, Wen Jing; Tan, Lu; Zhang, Jia Hui; Xu, Jiamin; Chen, Yi; Qin, Mengting; Yu, Shuang; Guan, Jing; Zhang, Rui

2017-06-01

Pancreatic beta cells are very sensitive to oxidative stress, which is one of the major causes of cell damages in diabetes. Growing interest has focused on the development of effective therapeutics to protect pancreatic cells from oxidative stress and searching for potentially protective antioxidants for treating diabetes. Apigenin, a plant-derived flavonoid, was investigated to determine whether it could protect rat insulinoma cell lines (RINm5F pancreatic beta cells) against streptozotocin (STZ)-induced oxidative damages and the mechanisms implicated. Our results showed that STZ treatment could induce oxidative stress and consequent cytotoxic effects in RINm5F cells. Pretreatment with apigenin effectively decreased the intracellular reactive oxygen species (ROS) production, attenuated cellular DNA damage, diminished lipid peroxidation, relieved protein carbonylation, and restored the cell apoptosis of pancreatic beta cells stressed by STZ. Our further experiments demonstrated that the beneficial effects of apigenin were related to ameliorate the loss of antioxidant enzymes of the STZ-treated cells in the level of gene transcription, protein expression, and enzyme activity. That suggested apigenin was not only a free radical scavenger but also a regulator to antioxidant defenses of pancreatic cells. Taken all together, our findings suggested that apigenin could attenuate the STZ-induced oxidative damages in pancreatic beta cells and might serve as a novel agent for the treatment of diabetes.

T Lymphocytes Do Not Directly Mediate the Protective Effect of Estrogen on Experimental Autoimmune Encephalomyelitis

PubMed Central

Polanczyk, Magdalena J.; Jones, Richard E.; Subramanian, Sandhya; Afentoulis, Michael; Rich, Cathleen; Zakroczymski, Melissa; Cooke, Paul; Vandenbark, Arthur A.; Offner, Halina

2004-01-01

Gender influences mediated by 17β-estradiol (E2) have been associated with susceptibility to and severity of autoimmune diseases such as diabetes, arthritis, and multiple sclerosis. In this regard, we have shown that estrogen receptor-α (Esr1) is crucial for the protective effect of 17β-estradiol (E2) in murine experimental autoimmune encephalitis (EAE), an animal model of multiple sclerosis. The expression of estrogen receptors among various immune cells (eg, T and B lymphocytes, antigen-presenting cells) suggests that the therapeutic effect of E2 is likely mediated directly through specific receptor binding. However, the target immune cell populations responsive to E2 treatment have not been identified. In the current study, we induced EAE in T-cell-deficient, severe combined immunodeficient mice or in immunocompetent mice with encephalitogenic T cells from wild-type Esr1+/+ or Esr1 knockout (Esr1−/−) donors and compared the protective E2 responses. The results showed that E2-responsive, Esr1+/+ disease-inducing encephalitogenic T cells were neither necessary nor sufficient for E2-mediated protection from EAE. Instead, the therapeutic response appeared to be mediated through direct effects on nonlymphocytic, E2-responsive cells and down-regulation of the inflammatory response in the central nervous system. These results provide the first demonstration that the protective effect of E2 on EAE is not mediated directly through E2-responsive T cells and raise the alternative possibility that nonlymphocytic cells such as macrophages, dendritic cells, or other nonlymphocytic cells are primarily responsive to E2 treatment in EAE. PMID:15579449

Protective effect of orexin-A on 6-hydroxydopamine-induced neurotoxicity in SH-SY5Y human dopaminergic neuroblastoma cells.

PubMed

Esmaeili-Mahani, Saeed; Vazifekhah, Somayeh; Pasban-Aliabadi, Hamzeh; Abbasnejad, Mehdi; Sheibani, Vahid

2013-12-01

Parkinson's disease (PD) is a progressive neurodegenerative disease characterized by progressive and selective death of midbrain dopaminergic neurons. Pharmacologic treatment of PD can be divided into symptomatic and neuroprotective therapies. Orexin-A (hypocretin-1) is a hypothalamic peptide that exerts its biological effects by stimulation of two specific, membrane-bound orexin receptors. Recent studies have shown that orexin-A has a protective role during neuronal damage. Here, we investigated the effects of orexin-A on 6-OHDA-induced neurotoxicity in human neuroblastoma SH-SY5Y cell line as an in vitro model of Parkinson's disease. Cell damage was induced by 150μM 6-OHDA and the cells viability was examined by MTT assay. Intracellular reactive oxygen species (ROS) was determined by fluorescence spectrophotometry method. Immunoblotting and DNA analysis were also employed to determine the levels of biochemical markers of apoptosis in the cells. The data showed that 6-OHDA could decrease the viability of the cells. In addition, intracellular ROS, activated caspase 3, Bax/Bcl-2 ratio, cytochrome c as well as DNA fragmentation were significantly increased in 6-OHDA-treated cells. Pretreatment of cells with orexin-A (80pM) elicited protective effect and reduced biochemical markers of cell death. The results suggest that orexin-A has protective effects against 6-OHDA-induced neurotoxicity and its protective effects are accompanied by its antioxidant and anti-apoptotic properties and contribute to our knowledge of the pharmacology of orexin-A. Copyright © 2013 Elsevier Ltd. All rights reserved.

Protection against radiation-induced oxidative stress in cultured human epithelial cells by treatment with antioxidant agents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wan, X. Steven; Ware, Jeffrey H.; Zhou, Zhaozong

2006-04-01

Purpose: To evaluate the protective effects of antioxidant agents against space radiation-induced oxidative stress in cultured human epithelial cells. Methods and Materials: The effects of selected concentrations of N-acetylcysteine, ascorbic acid, sodium ascorbate, co-enzyme Q10, {alpha}-lipoic acid, L-selenomethionine, and vitamin E succinate on radiation-induced oxidative stress were evaluated in MCF10 human breast epithelial cells exposed to radiation with X-rays, {gamma}-rays, protons, or high mass, high atomic number, and high energy particles using a dichlorofluorescein assay. Results: The results demonstrated that these antioxidants are effective in protecting against radiation-induced oxidative stress and complete or nearly complete protection was achieved by treatingmore » the cells with a combination of these agents before and during the radiation exposure. Conclusion: The combination of antioxidants evaluated in this study is likely be a promising countermeasure for protection against space radiation-induced adverse biologic effects.« less

Ethanol extract of Piper longum L. attenuates gentamicin-induced hair cell loss in neonatal cochlea cultures.

PubMed

Du, Xiao Fei; Song, Jae-Jun; Hong, Seungug; Kim, Jihye

2012-06-01

Piper longum L. (PL), also as known as long pepper, a well-known spice and traditional medicine in Asia and Pacific islands, has been reported to exhibit wide spectrum activity including antioxidant activity. However, little information is available on its protective effect on gentamicin (GM) induced ototoxicity which is commonly regarded as being mediated by reactive oxygen species and reactive nitrogen species. This study was undertaken to investigate the protective effect of PL ethanol extract on gentamicin-induced hair cell loss in neonatal cochlea cultures. Cochlea cultures from postnatal day 2-3 mice were used for analysis of the protective effects of PL against gentamicin-induced hair cell loss by phalloidin staining. E. coil cultures were used to determine whether PL interferes with the antibiotic activity of GM. Nitric oxide (NO)-scavenging activity of PL was also measured in vitro. GM induced significant dose-dependent hair cell loss in cochlea cultures. However, without interfering with the antibiotic activity of GM, PL showed a significant and concentration-dependent protective effect against GM-induced hair cell loss, and hair cells retained their stereocilia well. In addition, PL expressed direct scavenging activity toward NO radical liberated within solution of sodium nitroprusside. These findings demonstrate the protective effect of PL on GM-induced hair cell loss in neonatal cochlea cultures, and suggest that it might be of therapeutic benefit for treatment of GM-induced ototoxicity.

Combination of Nigella sativa with Glycyrrhiza glabra and Zingiber officinale augments their protective effects on doxorubicin-induced toxicity in h9c2 cells.

PubMed

Hosseini, Azar; Shafiee-Nick, Reza; Mousavi, Seyed Hadi

2014-12-01

The use of doxorubicin (DOX) is limited by its dose-dependent cardio toxicity in which reactive Oxygen Species (ROS) play an important role in the pathological process. The aim of this study was to evaluate the protective effect of three medicinal plants, Nigella sativa (N), Glycyrrhiza glabra (G) and Zingiber officinale (Z), and their combination (NGZ), against DOX-induced apoptosis and death in H9c2 cells. The cells were incubated with different concentrations of each extract or NGZ for 4 hr which continued in the presence or absence of 5µM doxorubicin for 24 hr. Cell viability and the apoptotic rate were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) and propidium iodide (PI) staining assays, respectively. The level of ROS and lipid peroxidation were measured by fluorimetric methods. Treatment with doxorubicin increased ROS generation, enhanced malondialdehyde (MDA) formation, and induced apoptosis. Co-treatment of the cells with each herb extract increased viability of cells dose-dependently with a maximum protection effect of about 30%, and their potencies were N>G>Z. The combination of the threshold dose of each extract (NGZ) produced a similar effect, which was increased dose-dependently to a maximum protection of 70%. These effects were correlated with the effects of NGZ on ROS and MDA. All of the extracts have some protective effects against DOX-induced toxicity in cardiomyocytes with similar efficacies, but with different potencies. However, NGZ produced much higher protective effect via reducing oxidative stress and inhibiting of apoptotic induction processes. Further investigations are needed to determine the effects of NGZ on DOX chemotherapy.

Combination of Nigella sativa with Glycyrrhiza glabra and Zingiber officinale augments their protective effects on doxorubicin-induced toxicity in h9c2 cells

PubMed Central

Hosseini, Azar; Shafiee-Nick, Reza; Mousavi, Seyed Hadi

2014-01-01

Objective(s): The use of doxorubicin (DOX) is limited by its dose-dependent cardio toxicity in which reactive Oxygen Species (ROS) play an important role in the pathological process. The aim of this study was to evaluate the protective effect of three medicinal plants, Nigella sativa (N), Glycyrrhiza glabra (G) and Zingiber officinale (Z), and their combination (NGZ), against DOX-induced apoptosis and death in H9c2 cells. Materials and Methods: The cells were incubated with different concentrations of each extract or NGZ for 4 hr which continued in the presence or absence of 5µM doxorubicin for 24 hr. Cell viability and the apoptotic rate were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) and propidium iodide (PI) staining assays, respectively. The level of ROS and lipid peroxidation were measured by fluorimetric methods. Results: Treatment with doxorubicin increased ROS generation, enhanced malondialdehyde (MDA) formation, and induced apoptosis. Co-treatment of the cells with each herb extract increased viability of cells dose-dependently with a maximum protection effect of about 30%, and their potencies were N>G>Z. The combination of the threshold dose of each extract (NGZ) produced a similar effect, which was increased dose-dependently to a maximum protection of 70%. These effects were correlated with the effects of NGZ on ROS and MDA. Conclusion: All of the extracts have some protective effects against DOX-induced toxicity in cardiomyocytes with similar efficacies, but with different potencies. However, NGZ produced much higher protective effect via reducing oxidative stress and inhibiting of apoptotic induction processes. Further investigations are needed to determine the effects of NGZ on DOX chemotherapy. PMID:25859303

Protective effects of a natural product, curcumin, against amyloid β induced mitochondrial and synaptic toxicities in Alzheimer's disease

PubMed Central

Reddy, P Hemachandra; Manczak, Maria; Yin, Xiangling; Grady, Mary Catharine; Mitchell, Andrew; Kandimalla, Ramesh; Kuruva, Chandra Sekhar

2016-01-01

The purpose of our study was to investigate the protective effects of a natural product—‘curcumin’— in Alzheimer's disease (AD)-like neurons. Although much research has been done in AD, very little has been reported on the effects of curcumin on mitochondrial biogenesis, dynamics, function and synaptic activities. Therefore, the present study investigated the protective effects against amyloid β (Aβ) induced mitochondrial and synaptic toxicities. Using human neuroblastoma (SHSY5Y) cells, curcumin and Aβ, we studied the protective effects of curcumin against Aβ. Further, we also studied preventive (curcumin+Aβ) and intervention (Aβ+curcumin) effects of curcumin against Aβ in SHSY5Y cells. Using real time RT-PCR, immunoblotting and immunofluorescence analysis, we measured mRNA and protein levels of mitochondrial dynamics, mitochondrial biogenesis and synaptic genes. We also assessed mitochondrial function by measuring hydrogen peroxide, lipid peroxidation, cytochrome oxidase activity and mitochondrial ATP. Cell viability was studied using the MTT assay. Aβ was found to impair mitochondrial dynamics, reduce mitochondrial biogenesis and decrease synaptic activity and mitochondrial function. In contrast, curcumin enhanced mitochondrial fusion activity and reduced fission machinery, and increased biogenesis and synaptic proteins. Mitochondrial function and cell viability were elevated in curcumin treated cells. Interestingly, curcumin pre- and post-treated cells incubated with Aβ showed reduced mitochondrial dysfunction, and maintained cell viability and mitochondrial dynamics, mitochondrial biogenesis and synaptic activity. Further, the protective effects of curcumin were stronger in pretreated SHSY5Y cells than in post-treated cells, indicating that curcumin works better in prevention than treatment in AD-like neurons. Our findings suggest that curcumin is a promising drug molecule to treat AD patients. PMID:27521081

Protective effects of a natural product, curcumin, against amyloid β induced mitochondrial and synaptic toxicities in Alzheimer's disease.

PubMed

Reddy, P Hemachandra; Manczak, Maria; Yin, Xiangling; Grady, Mary Catharine; Mitchell, Andrew; Kandimalla, Ramesh; Kuruva, Chandra Sekhar

2016-12-01

The purpose of our study was to investigate the protective effects of a natural product-'curcumin'- in Alzheimer's disease (AD)-like neurons. Although much research has been done in AD, very little has been reported on the effects of curcumin on mitochondrial biogenesis, dynamics, function and synaptic activities. Therefore, the present study investigated the protective effects against amyloid β (Aβ) induced mitochondrial and synaptic toxicities. Using human neuroblastoma (SHSY5Y) cells, curcumin and Aβ, we studied the protective effects of curcumin against Aβ. Further, we also studied preventive (curcumin+Aβ) and intervention (Aβ+curcumin) effects of curcumin against Aβ in SHSY5Y cells. Using real time RT-PCR, immunoblotting and immunofluorescence analysis, we measured mRNA and protein levels of mitochondrial dynamics, mitochondrial biogenesis and synaptic genes. We also assessed mitochondrial function by measuring hydrogen peroxide, lipid peroxidation, cytochrome oxidase activity and mitochondrial ATP. Cell viability was studied using the MTT assay. Aβ was found to impair mitochondrial dynamics, reduce mitochondrial biogenesis and decrease synaptic activity and mitochondrial function. In contrast, curcumin enhanced mitochondrial fusion activity and reduced fission machinery, and increased biogenesis and synaptic proteins. Mitochondrial function and cell viability were elevated in curcumin treated cells. Interestingly, curcumin pre- and post-treated cells incubated with Aβ showed reduced mitochondrial dysfunction, and maintained cell viability and mitochondrial dynamics, mitochondrial biogenesis and synaptic activity. Further, the protective effects of curcumin were stronger in pretreated SHSY5Y cells than in post-treated cells, indicating that curcumin works better in prevention than treatment in AD-like neurons. Our findings suggest that curcumin is a promising drug molecule to treat AD patients. Copyright © 2016 American Federation for Medical Research.

Capsaicin-Sensitive Sensory Nerves Are Necessary for the Protective Effect of Ghrelin in Cerulein-Induced Acute Pancreatitis in Rats

PubMed Central

Bonior, Joanna; Warzecha, Zygmunt; Ceranowicz, Piotr; Gajdosz, Ryszard; Pierzchalski, Piotr; Kot, Michalina; Leja-Szpak, Anna; Nawrot-Porąbka, Katarzyna; Link-Lenczowski, Paweł; Olszanecki, Rafał; Bartuś, Krzysztof; Trąbka, Rafał; Kuśnierz-Cabala, Beata; Dembiński, Artur; Jaworek, Jolanta

2017-01-01

Ghrelin was shown to exhibit protective and therapeutic effect in the gut. Aim of the study was to investigate the role of sensory nerves (SN) in the protective effect of ghrelin in acute pancreatitis (AP). Studies were performed on male Wistar rats or isolated pancreatic acinar cells. After capsaicin deactivation of sensory nerves (CDSN) or treatment with saline, rats were pretreated intraperitoneally with ghrelin or saline. In those rats, AP was induced by cerulein or pancreases were used for isolation of pancreatic acinar cells. Pancreatic acinar cells were incubated in cerulein-free or cerulein containing solution. In rats with intact SN, pretreatment with ghrelin led to a reversal of the cerulein-induced increase in pancreatic weight, plasma activity of lipase and plasma concentration of tumor necrosis factor-α (TNF-α). These effects were associated with an increase in plasma interleukin-4 concentration and reduction in histological signs of pancreatic damage. CDSN tended to increase the severity of AP and abolished the protective effect of ghrelin. Exposure of pancreatic acinar cells to cerulein led to increase in cellular expression of mRNA for TNF-α and cellular synthesis of this cytokine. Pretreatment with ghrelin reduced this alteration, but this effect was only observed in acinar cells obtained from rats with intact SN. Moreover, CDSN inhibited the cerulein- and ghrelin-induced increase in gene expression and synthesis of heat shock protein 70 (HSP70) in those cells. Ghrelin exhibits the protective effect in cerulein-induced AP on the organ and pancreatic acinar cell level. Sensory nerves ablation abolishes this effect. PMID:28665321

Low-level laser therapy prevents endothelial cells from TNF-α/cycloheximide-induced apoptosis.

PubMed

Chu, Yu-Hsiu; Chen, Shu-Ya; Hsieh, Yueh-Ling; Teng, Yi-Hsien; Cheng, Yu-Jung

2018-02-01

Low-level laser therapy (LLLT), widely used in physiotherapy, has been known to enhance wound healing and stimulate cell proliferation, including fibroblast and endothelial cells. Applying LLLT can increase cell proliferation in many kinds of cells including fibroblasts and endothelial cells. However, the protective mechanisms of LLLT on endothelial apoptosis remain unclear. We hypothesized LLLT can protect endothelial cells from inflammation-induced apoptosis. Human endothelial cell line, EA.hy926 cells, and TNF-α/cycloheximide (TNF/CHX) were used to explore the protective effects of LLLT (660 nm) on inflammation-induced endothelial apoptosis. Cell viability, apoptosis, caspase-3/7/8/9 activity, MAPKs signaling, NF-κB activity, and inducible/endothelial nitric oxide synthase (iNOS/eNOS) expression were measured. Our results showed that LLLT increased EA.hy926 cell proliferation, attenuated the TNF/CHX-induced apoptosis, and reduced the TNF/CHX-mediated caspase-3/7/8/9 activation. In addition, LLLT increased ERK MAPK phosphorylation and suppressed the TNF/CHX-increased p38 MAPK, JNK, IKK phosphorylation, NF-κB translocation, and iNOS expression. The caspases-3 cleavage and cell death were not increased in cells treating with ERK inhibitor U0126, which implicated that ERK is not to be responsible for the protective effects of LLLT. After treating with p38 mitogen-activated protein kinase (MAPK) activator, the protection of LLLT in cell apoptosis was no longer existed, showing that LLLT protected the endothelial cells by suppressing p38 MAPK signaling. Our results provide a new insight into the possible molecular mechanisms in which LLLT protects against inflammatory-induced endothelial dysfunction.

Vaccination with human amniotic epithelial cells confer effective protection in a murine model of Colon adenocarcinoma.

PubMed

Tabatabaei, M; Mosaffa, N; Ghods, R; Nikoo, S; Kazemnejad, S; Khanmohammadi, M; Mirzadeghan, E; Mahmoudi, A R; Bolouri, M R; Falak, R; Keshavarzi, B; Ramezani, M; Zarnani, A H

2018-04-01

As a prophylactic cancer vaccine, human amniotic membrane epithelial cells (hAECs) conferred effective protection in a murine model of colon cancer. The immunized mice mounted strong cross-protective CTL and antibody responses. Tumor burden was significantly reduced in tumor-bearing mice after immunization with hAECs. Placental cancer immunotherapy could be a promising approach for primary prevention of cancer. In spite of being the star of therapeutic strategies for cancer treatment, the results of immunotherapeutic approaches are still far from expectations. In this regard, primary prevention of cancer using prophylactic cancer vaccines has gained considerable attention. The immunologic similarities between cancer development and placentation have helped researchers to unravel molecular mechanisms responsible for carcinogenesis and to take advantage of stem cells from reproductive organs to elicit robust anti-cancer immune responses. Here, we showed that vaccination of mice with human amniotic membrane epithelial cells (hAECs) conferred effective protection against colon cancer and led to expansion of systemic and splenic cytotoxic T cell population and induction of cross-protective cytotoxic responses against tumor cells. Vaccinated mice mounted tumor-specific Th1 responses and produced cross-reactive antibodies against cell surface markers of cancer cells. Tumor burden was also significantly reduced in tumor-bearing mice immunized with hAECs. Our findings pave the way for potential future application of hAECs as an effective prophylactic cancer vaccine. © 2017 UICC.

Screen of FDA-approved drug library reveals compounds that protect hair cells from aminoglycosides and cisplatin

PubMed Central

Vlasits, Anna L.; Simon, Julian A.; Raible, David W.; Rubel, Edwin W; Owens, Kelly N.

2012-01-01

Loss of mechanosensory hair cells in the inner ear accounts for many hearing loss and balance disorders. Several beneficial pharmaceutical drugs cause hair cell death as a side effect. These include aminoglycoside antibiotics, such as neomycin, kanamycin and gentamicin, and several cancer chemotherapy drugs, such as cisplatin. Discovering new compounds that protect mammalian hair cells from toxic insults is experimentally difficult because of the inaccessibility of the inner ear. We used the zebrafish lateral line sensory system as an in vivo screening platform to survey a library of FDA-approved pharmaceuticals for compounds that protect hair cells from neomycin, gentamicin, kanamycin and cisplatin. Ten compounds were identified that provide protection from at least two of the four toxins. The resulting compounds fall into several drug classes, including serotonin and dopamine-modulating drugs, adrenergic receptor ligands, and estrogen receptor modulators. The protective compounds show different effects against the different toxins, supporting the idea that each toxin causes hair cell death by distinct, but partially overlapping, mechanisms. Furthermore, some compounds from the same drug classes had different protective properties, suggesting that they might not prevent hair cell death by their known target mechanisms. Some protective compounds blocked gentamicin uptake into hair cells, suggesting that they may block mechanotransduction or other routes of entry. The protective compounds identified in our screen will provide a starting point for studies in mammals as well as further research discovering the cellular signaling pathways that trigger hair cell death. PMID:22967486

ABCC1 is related to the protection of the distal nephron against hyperosmolality and high sodium environment: possible implications for cancer chemotherapy.

PubMed

Fonseca, Leonardo M; Alvarez, Adriana B; Rodrigues, Rachel C; Santos, Diego H F; Lopes, Anibal G; Capella, Marcia A M

2013-01-01

Glutathione (GSH) plays an important role in protecting cells against oxidative damage. ABCC1 protein transports GSH. Although this protein is largely studied in cancer, due to multidrug resistance phenotype, its role in the tubular cells of the kidney is unknown. The goal of this study was to find out whether ABCC1 has a role in protecting cells from the distal nephron against the stress caused by high medullar osmolality. MA104 cells were treated with high concentrations of sodium chloride, urea, or both to raise the osmolality of the culture medium. Cell viability was accessed by MTT and trypan blue assays. ABCC1 expression and extrusion of carboxi-fluorescein (CF), a fluorescent ABCC1 substrate, were measured by flow cytometry. Incubation of MA104 cells in a high sodium concentration medium resulted in changes in cell granularity and altered expression and activity of ABCC1. Urea did not alter ABCC1 expression or activity, but reversed the observed NaCl effects. High sodium concentrations also had a negative effect on cell viability and urea also protected cells against this effect. Our findings demonstrate that ABCC1 plays a significant role in the protection of kidney epithelial cells against the stress caused by high sodium environment present in renal medulla.

Lack of TXNIP protects against mitochondria-mediated apoptosis but not against fatty acid-induced ER stress-mediated beta-cell death.

PubMed

Chen, Junqin; Fontes, Ghislaine; Saxena, Geetu; Poitout, Vincent; Shalev, Anath

2010-02-01

We have previously shown that lack of thioredoxin-interacting protein (TXNIP) protects against diabetes and glucotoxicity-induced beta-cell apoptosis. Because the role of TXNIP in lipotoxicity is unknown, the goal of the present study was to determine whether TXNIP expression is regulated by fatty acids and whether TXNIP deficiency also protects beta-cells against lipoapoptosis. RESARCH DESIGN AND METHODS: To determine the effects of fatty acids on beta-cell TXNIP expression, INS-1 cells and isolated islets were incubated with/without palmitate and rats underwent cyclic infusions of glucose and/or Intralipid prior to islet isolation and analysis by quantitative real-time RT-PCR and immunoblotting. Using primary wild-type and TXNIP-deficient islets, we then assessed the effects of palmitate on apoptosis (transferase-mediated dUTP nick-end labeling [TUNEL]), mitochondrial death pathway (cytochrome c release), and endoplasmic reticulum (ER) stress (binding protein [BiP], C/EBP homologous protein [CHOP]). Effects of TXNIP deficiency were also tested in the context of staurosporine (mitochondrial damage) or thapsigargin (ER stress). Glucose elicited a dramatic increase in islet TXNIP expression both in vitro and in vivo, whereas fatty acids had no such effect and, when combined with glucose, even abolished the glucose effect. We also found that TXNIP deficiency does not effectively protect against palmitate or thapsigargin-induced beta-cell apoptosis, but specifically prevents staurosporine- or glucose-induced toxicity. Our results demonstrate that unlike glucose, fatty acids do not induce beta-cell expression of proapoptotic TXNIP. They further reveal that TXNIP deficiency specifically inhibits the mitochondrial death pathway underlying beta-cell glucotoxicity, whereas it has very few protective effects against ER stress-mediated lipoapoptosis.

The protective effect of calcium against genotoxicity of lead acetate administration on bone marrow and spermatocyte cells of mice in vivo.

PubMed

Aboul-Ela, Ezzat I

2002-04-26

The protective effect of calcium given orally by gavage with two doses (40 and 80mg/kg body weight) was evaluated against clastogenecity induced by lead acetate with two concentrations (200 and 400mg/kg diet) on bone marrow and spermatocyte cells of mice in vivo. The parameter screened was percentage of chromosomal aberrations with and without gaps and sperm abnormalities. Statistical analyses indicated the protection efficacy of calcium with the high dose rather than the other in both types of mouse cells. The observation from the laboratory tests, dealing that lead acetate can be considered as an environmental genotoxic material. We recommended that it must be administered of calcium (as calcium chloride) as a protective agent to reduce the genotoxic effect of lead in the somatic and germ cells.

Connecting Neuronal Cell Protective Pathways and Drug Combinations in a Huntington's Disease Model through the Application of Quantitative Systems Pharmacology.

PubMed

Pei, Fen; Li, Hongchun; Henderson, Mark J; Titus, Steven A; Jadhav, Ajit; Simeonov, Anton; Cobanoglu, Murat Can; Mousavi, Seyed H; Shun, Tongying; McDermott, Lee; Iyer, Prema; Fioravanti, Michael; Carlisle, Diane; Friedlander, Robert M; Bahar, Ivet; Taylor, D Lansing; Lezon, Timothy R; Stern, Andrew M; Schurdak, Mark E

2017-12-19

Quantitative Systems Pharmacology (QSP) is a drug discovery approach that integrates computational and experimental methods in an iterative way to gain a comprehensive, unbiased understanding of disease processes to inform effective therapeutic strategies. We report the implementation of QSP to Huntington's Disease, with the application of a chemogenomics platform to identify strategies to protect neuronal cells from mutant huntingtin induced death. Using the STHdh Q111 cell model, we investigated the protective effects of small molecule probes having diverse canonical modes-of-action to infer pathways of neuronal cell protection connected to drug mechanism. Several mechanistically diverse protective probes were identified, most of which showed less than 50% efficacy. Specific combinations of these probes were synergistic in enhancing efficacy. Computational analysis of these probes revealed a convergence of pathways indicating activation of PKA. Analysis of phospho-PKA levels showed lower cytoplasmic levels in STHdh Q111 cells compared to wild type STHdh Q7 cells, and these levels were increased by several of the protective compounds. Pharmacological inhibition of PKA activity reduced protection supporting the hypothesis that protection may be working, in part, through activation of the PKA network. The systems-level studies described here can be broadly applied to any discovery strategy involving small molecule modulation of disease phenotype.

Attenuation of doxorubicin-induced cardiotoxicity by esculetin through modulation of Bmi-1 expression.

PubMed

Xu, Fan; Li, Xiao; Liu, Lanfang; Xiao, Xu; Zhang, Li; Zhang, Shenglin; Lin, Pingping; Wang, Xiaojie; Wang, Yongwei; Li, Qingshan

2017-09-01

The protective effects and mechanisms of esculetin on doxorubicin (DOX)-induced injury of H9c2 cells were investigated. H9c2 cells were cultured and the logarithmic growth phase of the cells was divided into a control group, a DOX group and an esculetin + DOX group. Cell viability was detected by MTT assay. Annexin V-PI (AV-PI) double staining flow cytometry was carried out to detect cell apoptosis. Intracellular reactive oxygen species (ROS) were detected by flow cytometry. Transmission electron microscope (TEM) was used to evaluate cell ultrastructure. Cleaved caspase-3, cleaved PARP, Bcl-2, Bid and Bmi-1 proteins levels were investigated by western blot analysis. Bmi-1 siRNA was used to detect the role of Bmi-1 in the protective effects of esculetin against DOX-induced toxicity in H9c2 cells. The MTT and AV-PI double staining results showed that esculetin significantly increased H9c2 cell viability. Compared with the control group, the levels of cleaved caspase-3, cleaved PARP, Bid and ROS levels were significantly decreased, but the expression of Bcl-2 and Bmi-1 were significantly increased in the esculetin + DOX group. TEM showed that the cell structure of the mitochondria was protected by esculetin. The results of Bmi-1 siRNA showed that esculetin could protect DOX-induced cardiotoxicity by modulating Bmi-1 expression. Esculetin can protect DOX-induced cardiotoxicity and the effects may be attributable to modulation of Bmi-1 expression, provoking intracellular ROS accumulation, protecting the structure of mitochondria and reducing cell apoptosis.

Antitumor Effects In Vitro and In Vivo and Mechanisms of Protection against Melanoma B16F10-Nex2 Cells By Fastuosain, a Cysteine Proteinase from Bromelia fastuosa1

PubMed Central

Guimarães-Ferreira, Carla A; Rodrigues, Elaine G; Mortara, Renato A; Cabral, Hamilton; Serrano, Fabiana A; Ribeiro-dos-Santos, Ricardo; Travassos, Luiz R

2007-01-01

In the present work, the antitumor effect of fastuosain, a cysteine proteinase from Bromelia fastuosa, was investigated. In the intravenous model of lung colonization in C57Bl/6 mice, fastuosain and bromelain injected intraperitoneally were protective, and very few nodules of B16F10-Nex2 melanoma cells were detected. Tumor cells treated with fastuosain showed reduced expression of CD44 and decreased invasion through Matrigel, lost their cytoplasmic extensions and substrate adherence, and became round and detached, forming strongly bound cell clusters in suspension. Peritoneal cells recruited and activated by fastuosain treatment (mainly monocytic cells and lymphocytes) migrated to the lung, where pulmonary melanoma metastases grew. Adoptive transference of peritoneal cells recruited by fastuosain had no protective effect against lung metastases in recipient mice. Treatment of green fluorescent protein-chimeric animals with fastuosain did not change the number of cells that migrated to the lung, compared to PBS-injected control mice, but the number of positive major histocompatibility complex class II cells increased with fastuosain treatment. Murine antibodies against fastuosain, bromelain, and cathepsins B and L cross-reacted in ELISA and recognized surface and cytoplasmic components expressed on B16F10-Nex2 cells. Anti-fastuosain antibodies were cytotoxic/lytic to B16F10-Nex2 cells. Antitumor effects of fastuosain involve mainly the direct effect of the enzyme and elicitation of protective antibodies. PMID:17898868

Protective effect of Rehmannia glutinosa on the cisplatin-induced damage of HEI-OC1 auditory cells through scavenging free radicals.

PubMed

Yu, Hyeon-Hee; Seo, Se-Jeong; Kim, Yeon-Hwa; Lee, Hae-Youn; Park, Rae-Kil; So, Hong-Seob; Jang, Seon Ll; You, Yong-Ouk

2006-10-11

The steamed root of Rehmannia glutinosa has been used in traditional Oriental Medicine for treatment of inner ear diseases, such as tinnitus and hearing loss. In the present study, we showed that the ethanol extract of steamed roots of Rehmannia glutinosa (SRG) protected HEI-OC1 auditory cells from cisplatin cytotoxicity in a dose-dependent fashion. In addition, to investigate the protection mechanism of SRG on cisplatin cytotoxicity towards HEI-OC1, we measured the effects of SRG on lipid peroxidation of cisplatin treated cells as well as scavenging activities against superoxide radical, hydroxyl radical, hydrogen peroxide, and DPPH radical. SRG (5-100 microg/ml) had protective effect against the cisplatin-induced HEI-OC1 cell damage and reduced lipid peroxidation in a dose-dependent manner. Furthermore, SRG showed strong scavenging activity against superoxide radical, hydroxyl radical, hydrogen peroxide, and DPPH radical. These results indicate that SRG protects cisplatin-induced HEI-OC1 cell damage through inhibition of lipid peroxidation and scavenging activities of free radials.

Pathway-specific effect of caffeine on protection against UV irradiation-induced apoptosis in corneal epithelial cells.

PubMed

Wang, Ling; Lu, Luo

2007-02-01

To define the role of molecular interaction between the UV-induced JNK (c-Jun N-terminal kinase) cascade and corneal epithelial cell apoptosis and protection against apoptosis by caffeine. Rabbit and human corneal epithelial cells were cultured in DMEM/F12 medium containing 10% FBS and 5 microg/mL insulin at 37 degrees C in 5% CO(2). DNA fragmentation and ethidium bromide/acridine orange (EB/AO) nuclear staining were performed to detect cell death. Western blot, immunoprecipitation, and kinase assays were used to measure UV-induced mitogen-activated protein (MAP) kinase activity. UV irradiation-induced apoptosis through apoptosis signal-regulating kinase 1 (ASK1) and MAKK4 (SEK1) upstream from JNK was caffeine sensitive. Caffeine (1,3,7-trimethylxanthine), an agent that is one of the most popular additions to food consumed in the world and a potential enhancer of chemotherapy, effectively protected corneal epithelial cells against apoptosis by its specific effect on the JNK cascade. Theophylline (1,3-dimethylxanthine) exhibited an effect similar to that of caffeine on prevention of UV irradiation-induced apoptosis. However, alterations of either intracellular cAMP or Ca(2+) levels did not alter the effect of caffeine on the JNK signaling pathway. In addition, the blockade of PI3K-like kinases by wortmannin had no impact on the protective effect of caffeine against UV irradiation-induced apoptosis, suggesting that the protective effect of caffeine acts through a specific mechanism involving UV irradiation-induced activation of ASK1 and SEK1. In contrast, caffeine had no effects on melphalan-, hyperosmotic stress-, or IL-1beta-induced activation of the JNK signaling pathway in these cells. UV irradiation stress-induced activation of the ASK1-SEK1-JNK signaling pathway leading to apoptosis is a caffeine-sensitive process, and caffeine, as a multifunctional agent in cells, can specifically interact with the pathway to protect against apoptosis.

Contrasting protective effects of cannabinoids against oxidative stress and amyloid-β evoked neurotoxicity in vitro.

PubMed

Harvey, Benjamin S; Ohlsson, Katharina S; Mååg, Jesper L V; Musgrave, Ian F; Smid, Scott D

2012-01-01

Cannabinoids have been widely reported to have neuroprotective properties in vitro and in vivo. In this study we compared the effects of CB1 and CB2 receptor-selective ligands, the endocannabinoid anandamide and the phytocannabinoid cannabidiol, against oxidative stress and the toxic hallmark Alzheimer's protein, β-amyloid (Aβ) in neuronal cell lines. PC12 or SH-SY5Y cells were selectively exposed to either hydrogen peroxide, tert-butyl hydroperoxide or Aβ, alone or in the presence of the CB1 specific agonist arachidonyl-2'-chloroethylamide (ACEA), CB2 specific agonist JWH-015, anandamide or cannabidiol. Cannabidiol improved cell viability in response to tert-butyl hydroperoxide in PC12 and SH-SY5Y cells, while hydrogen peroxide-mediated toxicity was unaffected by cannabidiol pretreatment. Aβ exposure evoked a loss of cell viability in PC12 cells. Of the cannabinoids tested, only anandamide was able to inhibit Aβ-evoked neurotoxicity. ACEA had no effect on Aβ-evoked neurotoxicity, suggesting a CB1 receptor-independent effect of anandamide. JWH-015 pretreatment was also without protective influence on PC12 cells from either pro-oxidant or Aβ exposure. None of the cannabinoids directly inhibited or disrupted preformed Aβ fibrils and aggregates. In conclusion, the endocannabinoid anandamide protects neuronal cells from Aβ exposure via a pathway unrelated to CB1 or CB2 receptor activation. The protective effect of cannabidiol against oxidative stress does not confer protection against Aβ exposure, suggesting divergent pathways for neuroprotection of these two cannabinoids. Copyright © 2011 Elsevier Inc. All rights reserved.

Neuroprotective effect of Aronia melanocarpa extract against glutamate-induced oxidative stress in HT22 cells.

PubMed

Lee, Hyeon Yong; Weon, Jin Bae; Ryu, Gahee; Yang, Woo Seung; Kim, Nam Young; Kim, Myong Ki; Ma, Choong Je

2017-04-11

Glutamate (an endogenous excitatory neurotransmitter) at high concentrations contributes to the development of neurodegenerative diseases. Aronia melanocarpa (A. melanocarpa) berries contain anthocyanins and have high antioxidant activities. In this study, we evaluated whether A. melanocarpa berries could protect neuronal cells against glutamate-induced oxidative stress. A. melanocarpa berries exerted a protective effect against cytotoxicity in HT22 mouse hippocampal cells by MTT assay. We evaluated oxidative stress parameters including ROS level, intracellular Ca 2+ level, glutathione level and antioxidant enzyme activity in HT22 cells to elucidate the mechanism of its neuroprotective effect. A. melanocarpa berries decreased glutamate-induced death of HT22 cells. In addition, A. melanocarpa berries reduced ROS and intracellular Ca 2+ levels. Glutathione level, antioxidant enzymes, glutathione reductase and glutathione peroxide activities and mitochondrial membrane potential were also increased in HT22 cells. These results suggested that A. melanocarpa berries protected HT22 cells by exerting an antioxidant effect.

Protection and Sensitization of Human Cells to Proton Radiation by Cerium Oxide Nanoparticles

NASA Astrophysics Data System (ADS)

Carlson, Nathan B.

In radiation therapy for the treatment of cancer, there is demand for novel approaches that will improve tumor cell killing while protecting healthy tissue. One such approach that has shown considerable promise is the application of nanoparticles as radiation sensitizers for tumor cells and as radiation protectants for healthy tissue. In this investigation, cerium oxide nanoparticles (CNPs) obtained from the University of Central Florida's NanoScience Technology Center were studied for their protective effect to charged particle radiation in non-malignant breast cells, and for their sensitizing effect in breast and prostate cancer cell lines. These experiments were conducted at East Carolina University, where human cells were grown in the cell culture facility in the Department of Biology and then irradiated with energetic protons in the Accelerator Laboratory in the Department of Physics. Prior to irradiation, the cells were treated with distinct CNP preparations ranging in concentrations from 10 nanomolar to 10 micromolar, and cell viability was assessed using multiple assays post-irradiation. Radioprotection and radiosensitization were observed for several of the CNP treatments tested. Ultimately, the goal is to find a specific nanoparticle treatment that holds the synergistic effect of enhancing the rate of killing in tumor cells while simultaneously improving the survival of normal cells.

Neurotensin protects pancreatic beta cells from apoptosis.

PubMed

Coppola, Thierry; Béraud-Dufour, Sophie; Antoine, Aurélie; Vincent, Jean-Pierre; Mazella, Jean

2008-01-01

The survival of pancreatic beta cells depends on the balance between external cytotoxic and protective molecular systems. The neuropeptide neurotensin (NT) has been shown to regulate certain functions of the endocrine pancreas including insulin and glucagon release. However, the mechanism of action of NT as well as the identification of receptors involved in the pancreatic functions of the peptide remained to be studied. We demonstrate here that NT is an efficient protective agent of pancreatic beta cells against cytotoxic agents. Both beta-TC3 and INS-1E cell lines and the mouse pancreatic islet cells express the three known NT receptors. The incubation of beta cells with NT protects cells from apoptosis induced either by staurosporine or by IL-1beta. In beta-TC3 cells, NT activates both MAP and PI-3 kinases pathways and strongly reduces the staurosporine or the Il-1beta-induced caspase-3 activity by a mechanism involving Akt activation. The NTSR2 agonist levocabastine displays the same protective effect than NT whereas the NTSR1 antagonist is unable to block the effect of NT suggesting the predominant involvement of the NTSR2 in the action of NT on beta cells. These results clearly indicate for the first time that NT is able to protect endocrine beta cells from external cytotoxic agents, a role well correlated with its release in the circulation after a meal.

Differential protective effects of immune lymphoid cells against transplanted line Ib leukemia and immune polioencephalomyelitis. [X radiation, mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duffey, P.S.; Lukasewycz, O.A.; Olson, D.S.

1978-12-01

The capacity of immune cells obtained from the major lymphoid compartments to protect C58 mice from transplanted line Ib leukemia, and from an age-dependent autoimmune CNS disease (immune polioencephalomyelitis = IPE) elicited by immunizing old C58 mice with inactivated Ib cells was quantified. Cells used for comparative adoptive protection tests were harvested from the major lymphoid compartments 14 to 15 days after young C58 mice were immunized with inactivated Ib cell preparations. Regression curves were plotted from survival data and the log/sub 10/PD/sub 50/ values were determined. Immune spleen (ISC) and peritoneal cells (IPEC) were significantly more protective against transplantedmore » Ib cells than immune lymph node (ILNC), thymic (ITC), and marrow cells (IMC). In contrast, IPEC and IMC were not protective against IPE and ITC were only marginally protective. ILNC afforded significant protection to transplantable leukemia but were only marginally protective to IPE. When ISC were treated with anti-thy 1.2 serum and complement, protection against transplanted leukemia and IPE was reduced > 99%. When donors of immune lymphoid cells were treated with 12.5 mg of cortisone acetate daily for 2 days before lymphoid cells were harvested, protection against transplanted Ib cells by ISC was reduced by approximately 90% whereas protection against IPE was totally eliminated. Considered together, these results indicate that the protective mechanisms to transplantable leukemia and IPE differ significantly in the same indicator mouse strain.« less

Selective Impairment of TH17-Differentiation and Protection against Autoimmune Arthritis after Overexpression of BCL2A1 in T Lymphocytes.

PubMed

Iglesias, Marcos; Augustin, Juan Jesús; Alvarez, Pilar; Santiuste, Inés; Postigo, Jorge; Merino, Jesús; Merino, Ramón

2016-01-01

The inhibition of apoptotic cell death in T cells through the dysregulated expression of BCL2 family members has been associated with the protection against the development of different autoimmune diseases. However, multiple mechanisms were proposed to be responsible for such protective effect. The purpose of this study was to explore the effect of the T-cell overexpression of BCL2A1, an anti-apoptotic BCL2 family member without an effect on cell cycle progression, in the development of collagen-induced arthritis. Our results demonstrated an attenuated development of arthritis in these transgenic mice. The protective effect was unrelated to the suppressive activity of regulatory T cells but it was associated with a defective activation of p38 mitogen-activated protein kinase in CD4+ cells after in vitro TCR stimulation. In addition, the in vitro and in vivo TH17 differentiation were impaired in BCL2A1 transgenic mice. Taken together, we demonstrated here a previously unknown role for BCL2A1 controlling the activation of CD4+ cells and their differentiation into pathogenic proinflammatory TH17 cells and identified BCL2A1 as a potential target in the control of autoimmune/inflammatory diseases.

Prion Protein Does Not Confer Resistance to Hippocampus-Derived Zpl Cells against the Toxic Effects of Cu2+, Mn2+, Zn2+ and Co2+ Not Supporting a General Protective Role for PrP in Transition Metal Induced Toxicity

PubMed Central

Cingaram, Pradeep Kumar Reddy; Nyeste, Antal; Dondapati, Divya Teja; Fodor, Elfrieda; Welker, Ervin

2015-01-01

The interactions of transition metals with the prion protein (PrP) are well-documented and characterized, however, there is no consensus on their role in either the physiology of PrP or PrP-related neurodegenerative disorders. PrP has been reported to protect cells from the toxic stimuli of metals. By employing a cell viability assay, we examined the effects of various concentrations of Cu2+, Zn2+, Mn2+, and Co2+ on Zpl (Prnp -/-) and ZW (Prnp +/+) hippocampus-derived mouse neuronal cells. Prnp -/- Zpl cells were more sensitive to all four metals than PrP-expressing Zw cells. However, when we introduced PrP or only the empty vector into Zpl cells, we could not discern any protective effect associated with the presence of PrP. This observation was further corroborated when assessing the toxic effect of metals by propidium-iodide staining and fluorescence activated cell sorting analysis. Thus, our results on this mouse cell culture model do not seem to support a strong protective role for PrP against transition metal toxicity and also emphasize the necessity of extreme care when comparing cells derived from PrP knock-out and wild type mice. PMID:26426582

TNFR2-deficient memory CD8 T cells provide superior protection against tumor cell growth.

PubMed

Kim, Edward Y; Teh, Soo-Jeet; Yang, Jocelyn; Chow, Michael T; Teh, Hung-Sia

2009-11-15

TNF receptor-2 (TNFR2) plays a critical role in promoting the activation and survival of naive T cells during the primary response. Interestingly, anti-CD3 plus IL-2 activated TNFR2(-/-) CD8 T cells are highly resistant to activation-induced cell death (AICD), which correlates with high expression levels of prosurvival molecules such as Bcl-2, survivin, and CD127 (IL-7Ralpha). We determined whether the resistance of activated TNFR2(-/-) CD8 T cells to AICD contributes to more effective protection against tumor cell growth. We found that during a primary tumor challenge, despite initial inferiority in controlling tumor cell growth, TNFR2(-/-) mice were able to more effectively control tumor burden over time compared with wild-type (WT) mice. Furthermore, vaccination of TNFR2(-/-) mice with recombinant Listeria monocytogenes that express OVA confers better protection against the growth of OVA-expressing E.G7 tumor cells relative to similarly vaccinated WT mice. The enhanced protection against tumor cell growth was not due to more effective activation of OVA-specific memory CD8 T cells in vaccinated TNFR2(-/-) mice. In vitro studies indicate that optimally activated OVA-specific TNFR2(-/-) CD8 T cells proliferated to the same extent and possess similar cytotoxicity against E.G7 tumor cells as WT CD8 T cells. However, relative to WT cells, activated OVA-specific TNFR2(-/-) CD8 T cells were highly resistant to AICD. Thus, the enhanced protection against E.G7 in TNFR2(-/-) mice is likely due to the recruitment and activation of OVA-specific memory TNFR2(-/-) CD8 T cells and their prolonged survival at the tumor site.

Black rice extract protected HepG2 cells from oxidative stress-induced cell death via ERK1/2 and Akt activation

PubMed Central

Yoon, Jaemin; Ham, Hyeonmi; Sung, Jeehye; Kim, Younghwa; Choi, Youngmin; Lee, Jeom-Sig; Jeong, Heon-Sang; Lee, Junsoo

2014-01-01

BACKGROUND/OBJECTIVES The objective of this study was to evaluate the protective effect of black rice extract (BRE) on tert-butyl hydroperoxide (TBHP)-induced oxidative injury in HepG2 cells. MATERIALS/METHODS Methanolic extract from black rice was evaluated for the protective effect on TBHP-induced oxidative injury in HepG2 cells. Several biomarkers that modulate cell survival and death including reactive oxygen species (ROS), caspase-3 activity, and related cellular kinases were determined. RESULTS TBHP induced cell death and apoptosis by a rapid increase in ROS generation and caspase-3 activity. Moreover, TBHP-induced oxidative stress resulted in a transient ERK1/2 activation and a sustained increase of JNK1/2 activation. While, BRE pretreatment protects the cells against oxidative stress by reducing cell death, caspase-3 activity, and ROS generation and also by preventing ERKs deactivation and the prolonged JNKs activation. Moreover, pretreatment of BRE increased the activation of ERKs and Akt which are pro-survival signal proteins. However, this effect was blunted in the presence of ERKs and Akt inhibitors. CONCLUSIONS These results suggest that activation of ERKs and Akt pathway might be involved in the cytoprotective effect of BRE against oxidative stress. Our findings provide new insights into the cytoprotective effects and its possible mechanism of black rice against oxidative stress. PMID:24741394

CDDO-Me protects normal lung and breast epithelial cells but not cancer cells from radiation.

PubMed

El-Ashmawy, Mariam; Delgado, Oliver; Cardentey, Agnelio; Wright, Woodring E; Shay, Jerry W

2014-01-01

Although radiation therapy is commonly used for treatment for many human diseases including cancer, ionizing radiation produces reactive oxygen species that can damage both cancer and healthy cells. Synthetic triterpenoids, including CDDO-Me, act as anti-inflammatory and antioxidant modulators primarily by inducing the transcription factor Nrf2 to activate downstream genes containing antioxidant response elements (AREs). In the present series of experiments, we determined if CDDO-Me can be used as a radioprotector in normal non-cancerous human lung and breast epithelial cells, in comparison to lung and breast cancer cell lines. A panel of normal non-cancerous, partially cancer progressed, and cancer cell lines from both lung and breast tissue was exposed to gamma radiation with and without pre-treatment with CDDO-Me. CDDO-Me was an effective radioprotector when given ∼18 hours before radiation in epithelial cells (average dose modifying factor (DMF) = 1.3), and Nrf2 function was necessary for CDDO-Me to exert these radioprotective effects. CDDO-Me did not protect cancer lines tested from radiation-induced cytotoxicity, nor did it protect experimentally transformed human bronchial epithelial cells (HBECs) with progressive oncogenic manipulations. CDDO-Me also protected human lymphocytes against radiation-induced DNA damage. A therapeutic window exists in which CDDO-Me protects normal cells from radiation by activating the Nrf2 pathway, but does not protect experimentally transformed or cancer cell lines. This suggests that use of this oral available, non-toxic class of drug can protect non-cancerous healthy cells during radiotherapy, resulting in better outcomes and less toxicity for patients.

CDDO-Me Protects Normal Lung and Breast Epithelial Cells but Not Cancer Cells from Radiation

PubMed Central

El-Ashmawy, Mariam; Delgado, Oliver; Cardentey, Agnelio; Wright, Woodring E.; Shay, Jerry W.

2014-01-01

Although radiation therapy is commonly used for treatment for many human diseases including cancer, ionizing radiation produces reactive oxygen species that can damage both cancer and healthy cells. Synthetic triterpenoids, including CDDO-Me, act as anti-inflammatory and antioxidant modulators primarily by inducing the transcription factor Nrf2 to activate downstream genes containing antioxidant response elements (AREs). In the present series of experiments, we determined if CDDO-Me can be used as a radioprotector in normal non-cancerous human lung and breast epithelial cells, in comparison to lung and breast cancer cell lines. A panel of normal non-cancerous, partially cancer progressed, and cancer cell lines from both lung and breast tissue was exposed to gamma radiation with and without pre-treatment with CDDO-Me. CDDO-Me was an effective radioprotector when given ∼18 hours before radiation in epithelial cells (average dose modifying factor (DMF) = 1.3), and Nrf2 function was necessary for CDDO-Me to exert these radioprotective effects. CDDO-Me did not protect cancer lines tested from radiation-induced cytotoxicity, nor did it protect experimentally transformed human bronchial epithelial cells (HBECs) with progressive oncogenic manipulations. CDDO-Me also protected human lymphocytes against radiation-induced DNA damage. A therapeutic window exists in which CDDO-Me protects normal cells from radiation by activating the Nrf2 pathway, but does not protect experimentally transformed or cancer cell lines. This suggests that use of this oral available, non-toxic class of drug can protect non-cancerous healthy cells during radiotherapy, resulting in better outcomes and less toxicity for patients. PMID:25536195

Stem cell factor (SCF) protects osteoblasts from oxidative stress through activating c-Kit-Akt signaling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Lei; Wu, Zhong; Yin, Gang

2014-12-12

Highlights: • SCF receptor c-Kit is functionally expressed in primary and transformed osteoblasts. • SCF protects primary and transformed osteoblasts from H{sub 2}O{sub 2}. • SCF activation of c-Kit in osteoblasts, required for its cyto-protective effects. • c-Kit mediates SCF-induced Akt activation in cultured osteoblasts. • Akt activation is required for SCF-regulated cyto-protective effects in osteoblasts. - Abstract: Osteoblasts regulate bone formation and remodeling, and are main target cells of oxidative stress in the progression of osteonecrosis. The stem cell factor (SCF)-c-Kit pathway plays important roles in the proliferation, differentiation and survival in a range of cell types, but littlemore » is known about its functions in osteoblasts. In this study, we found that c-Kit is functionally expressed in both osteoblastic-like MC3T3-E1 cells and primary murine osteoblasts. Its ligand SCF exerted significant cyto-protective effects against hydrogen peroxide (H{sub 2}O{sub 2}). SCF activated its receptor c-Kit in osteoblasts, which was required for its cyto-protective effects against H{sub 2}O{sub 2}. Pharmacological inhibition (by Imatinib and Dasatinib) or shRNA-mediated knockdown of c-Kit thus inhibited SCF-mediated osteoblast protection. Further investigations showed that protection by SCF against H{sub 2}O{sub 2} was mediated via activation of c-Kit-dependent Akt pathway. Inhibition of Akt activation, through pharmacological or genetic means, suppressed SCF-mediated anti-H{sub 2}O{sub 2} activity in osteoblasts. In summary, we have identified a new SCF-c-Kit-Akt physiologic pathway that protects osteoblasts from H{sub 2}O{sub 2}-induced damages, and might minimize the risk of osteonecrosis caused by oxidative stress.« less

Identification of Plants That Inhibit Lipid Droplet Formation in Liver Cells: Rubus suavissimus Leaf Extract Protects Mice from High-Fat Diet-Induced Fatty Liver by Directly Affecting Liver Cells

PubMed Central

Takahashi, Tomohiro; Sugawara, Wataru; Takiguchi, Yuya; Takizawa, Kento; Nakabayashi, Ami; Nakamura, Mitsuo; Nagano-Ito, Michiyo; Ichikawa, Shinichi

2016-01-01

Fatty liver disease is a condition in which abnormally large numbers of lipid droplets accumulate in liver cells. Fatty liver disease induces inflammation under conditions of oxidative stress and may result in cancer. To identify plants that protect against fatty liver disease, we examined the inhibitory effects of plant extracts on lipid droplet formation in mouse hepatoma cells. A screen of 98 water extracts of plants revealed 4 extracts with inhibitory effects. One of these extracts, Rubus suavissimus S. Lee (Tien-cha or Chinese sweet tea) leaf extract, which showed strong inhibitory effects, was tested in a mouse fatty liver model. In these mouse experiments, intake of the plant extract significantly protected mice against fatty liver disease without affecting body weight gain. Our results suggest that RSE directly affects liver cells and protects them from fatty liver disease. PMID:27429636

Krebs Cycle Intermediates Protective against Oxidative Stress by Modulating the Level of Reactive Oxygen Species in Neuronal HT22 Cells.

PubMed

Sawa, Kenta; Uematsu, Takumi; Korenaga, Yusuke; Hirasawa, Ryuya; Kikuchi, Masatoshi; Murata, Kyohei; Zhang, Jian; Gai, Xiaoqing; Sakamoto, Kazuichi; Koyama, Tomoyuki; Satoh, Takumi

2017-03-16

Krebs cycle intermediates (KCIs) are reported to function as energy substrates in mitochondria and to exert antioxidants effects on the brain. The present study was designed to identify which KCIs are effective neuroprotective compounds against oxidative stress in neuronal cells. Here we found that pyruvate, oxaloacetate, and α-ketoglutarate, but not lactate, citrate, iso-citrate, succinate, fumarate, or malate, protected HT22 cells against hydrogen peroxide-mediated toxicity. These three intermediates reduced the production of hydrogen peroxide-activated reactive oxygen species, measured in terms of 2',7'-dichlorofluorescein diacetate fluorescence. In contrast, none of the KCIs-used at 1 mM-protected against cell death induced by high concentrations of glutamate-another type of oxidative stress-induced neuronal cell death. Because these protective KCIs did not have any toxic effects (at least up to 10 mM), they have potential use for therapeutic intervention against chronic neurodegenerative diseases.

MicroRNA-7 Promotes Glycolysis to Protect against 1-Methyl-4-phenylpyridinium-induced Cell Death.

PubMed

Chaudhuri, Amrita Datta; Kabaria, Savan; Choi, Doo Chul; Mouradian, M Maral; Junn, Eunsung

2015-05-08

Parkinson disease is associated with decreased activity of the mitochondrial electron transport chain. This defect can be recapitulated in vitro by challenging dopaminergic cells with 1-methyl-4-phenylpyridinium (MPP(+)), a neurotoxin that inhibits complex I of electron transport chain. Consequently, oxidative phosphorylation is blocked, and cells become dependent on glycolysis for ATP production. Therefore, increasing the rate of glycolysis might help cells to produce more ATP to meet their energy demands. In the present study, we show that microRNA-7, a non-coding RNA that protects dopaminergic neuronal cells against MPP(+)-induced cell death, promotes glycolysis in dopaminergic SH-SY5Y and differentiated human neural progenitor ReNcell VM cells, as evidenced by increased ATP production, glucose consumption, and lactic acid production. Through a series of experiments, we demonstrate that targeted repression of RelA by microRNA-7, as well as subsequent increase in the neuronal glucose transporter 3 (Glut3), underlies this glycolysis-promoting effect. Consistently, silencing Glut3 expression diminishes the protective effect of microRNA-7 against MPP(+). Further, microRNA-7 fails to prevent MPP(+)-induced cell death when SH-SY5Y cells are cultured in a low glucose medium, as well as when differentiated ReNcell VM cells or primary mouse neurons are treated with the hexokinase inhibitor, 2-deoxy-d-glucose, indicating that a functional glycolytic pathway is required for this protective effect. In conclusion, microRNA-7, by down-regulating RelA, augments Glut3 expression, promotes glycolysis, and subsequently prevents MPP(+)-induced cell death. This protective effect of microRNA-7 could be exploited to correct the defects in oxidative phosphorylation in Parkinson disease. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

The abolition of the protective effect of Pasteurella septica antiserum by iron compounds

PubMed Central

Bullen, J. J.; Wilson, A. B.; Cushnie, G. H.; Rogers, Henry J.

1968-01-01

Ferric ammonium citrate, haematin hydrochloride, soluble haematin, lysed mouse red cells and a variety of purified haemoglobins abolished the protective effect of Pasteurella septica antiserum in mice when the iron compounds were injected intraperitoneally with P. septica. Ferric ammonium citrate was less effective than haematin or lysed red cells when the dose of P. septica was reduced to less than 105. The ability of lysed red cells to abolish protection was greatly reduced if given 4 hours or more after infection. P. septica grew rapidly in unimmunized normal mice. In passively immunized mice the number of viable bacteria declined rapidly after infection. In passively immunized mice given haematin or lysed red cells the growth of bacteria was identical to that seen in unprotected normal mice. Large numbers of dead P. septica or carbon particles did not interfere with passive protection. PMID:5661980

Cytogenetic studies on Nigella sativa seeds extract and thymoquinone on mouse cells infected with schistosomiasis using karyotyping.

PubMed

Aboul-Ela, Ezzat I

2002-04-26

The protective effect of Nigella sativa seed extract and its main constituents thymoquinone (TQ) was studied on mouse cells infected with schistosomiasis. Bone marrow cells in the in vivo experiments and spleen cells in the in vitro one were used to evaluate the potentially protective effect of these natural compounds on the induction of chromosomal aberrations. Karyotyping of the mice cells illustrated that the main abnormalities were gaps, fragments and deletions especially in chromosomes 2, 6 and some in chromosomes 13 and 14. Both N. sativa extract and TQ were considered as protective agents against the chromosomal aberrations induced as a result of schistosomiasis.

Protective effects of anti-ricin A-chain RNA aptamer against ricin toxicity

PubMed Central

Fan, Shaoan; Wu, Feng; Martiniuk, Frank; Hale, Martha L; Ellington, Andrew D; Tchou-Wong, Kam-Meng

2008-01-01

AIM: To investigate the therapeutic potential of an RNA ligand (aptamer) specific for the catalytic ricin A-chain (RTA), the protective effects of a 31-nucleotide RNA aptamer (31RA), which formed a high affinity complex with RTA, against ricin-induced toxicity in cell-based luciferase translation and cell cytotoxicity assays were evaluated. METHODS: To test the therapeutic potential of anti-RTA aptamers in Chinese hamster ovary (CHO) AA8 cells stably transfected with a tetracycline regulatable promoter, ricin ribotoxicity was measured using luciferase and ricin-induced cytotoxicity was ascertained by MTS cell proliferation assay with tetrazolium compound [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium]. RESULTS: Inhibition of protein synthesis by ricin in CHO AA8 cells resulted in diminished luciferase activity and treatment with polyclonal antibody against deglycosylated RTA (dgA) neutralized the inhibitory effects of ricin on luciferase activity and protected against ricin-induced cytotoxicity as measured by MTS assay. The 31RA anti-RTA aptamer inhibited the translation of luciferase mRNA in cell-free reticulocyte translation assay. 31RA aptamer also partially neutralized the inhibitory effects of ricin on luciferase activity and partially protected against ricin-induced cytotoxicity in CHO AA8 cells. CONCLUSION: We have shown that anti-RTA RNA aptamer can protect against ricin ribotoxicity in cell-based luciferase and cell cytotoxicity assays. Hence, RNA aptamer that inhibits RTA enzymatic activity represents a novel class of nucleic acid inhibitor that has the potential to be developed as a therapeutic agent for the treatment of ricin intoxication. PMID:19009652

Colored lenses suppress blue light-emitting diode light-induced damage in photoreceptor-derived cells.

PubMed

Hiromoto, Kaho; Kuse, Yoshiki; Tsuruma, Kazuhiro; Tadokoro, Nobuyuki; Kaneko, Nobuyuki; Shimazawa, Masamitsu; Hara, Hideaki

2016-03-01

Blue light-emitting diodes (LEDs) in liquid crystal displays emit high levels of blue light, exposure to which is harmful to the retina. Here, we investigated the protective effects of colored lenses in blue LED light-induced damage to 661W photoreceptor-derived cells. We used eight kinds of colored lenses and one lens that reflects blue light. Moreover, we evaluated the relationship between the protective effects of the lens and the transmittance of lens at 464 nm. Lenses of six colors, except for the SY, PN, and reflective coating lenses, strongly decreased the reduction in cell damage induced by blue LED light exposure. The deep yellow lens showed the most protective effect from all the lenses, but the reflective coating lens and pink lens did not show any effects on photoreceptor-derived cell damage. Moreover, these results were correlated with the lens transmittance of blue LED light (464 nm). These results suggest that lenses of various colors, especially deep yellow lenses, may protect retinal photoreceptor cells from blue LED light in proportion to the transmittance for the wavelength of blue LED and the suppression of reactive oxygen species production and cell damage.

Immunity to sporozoite-induced malaria infection in mice. I. The effect of immunization of T and B cell-deficient mice. [X Radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, D.H.; Tigelaar, R.E.; Weinbaum, F.I.

1977-04-01

The cellular basis of immunity to sporozoites was investigated by examining the effect of immunization of T and B cell-deficient C57BL/6N x BALB/c AnN F/sub 1/ (BLCF/sub 1/) mice compared to immunocompetent controls. Immunization of T cell-deficient (ATX-BM-ATS) BLCF/sub 1/ mice with x-irradiated sporozoites did not result in the generation of protective immunity. The same immunization protocols protected all immunocompetent controls. In contrast, B cell-deficient (..mu..-suppressed) BLCF/sub 1/ mice were protected by immunization in the majority of cases. The absence of detectable serum circumsporozoite precipitins or sporozoite neutralizing activity in the ..mu..-suppressed mice that resisted a sporozoite challenge suggests amore » minor role for these humoral factors in protection. These data demonstrate a preeminent role for T cells in the induction of protective immunity in BLCF/sub 1/ mice against a P. berghei sporozoite infection.« less

The protective effect of pentoxifylline versus silymarin on the pancreas through increasing adenosine by CD39 in a rat model of liver cirrhosis: Pharmacological, biochemical and histological study.

PubMed

Mohamed, Doaa I; Nabih, Enas S; El-Waseef, Dalia A A; El-Kharashi, Omnyah A; Abd El Samad, Abeer A

2018-04-20

Impaired glucose homoeostasis due to insulin resistance and decrease sensitivity of pancreatic β-cells is a feature of liver disease and results into hepatogenous diabetes. Decrease expression of CD39 was linked to inflammation and occurrence of diabetes. Therefore, we performed this study to explore the protective effect of pentoxifylline (PTX) and silymarin administration on the β-cells of the pancreas in a rat model of thioacetamide induced liver cirrhosis. Biochemical, histological and immunohistochemistry studies of the liver and pancreas were performed and provided an evidence on the protective effect of PTX to pancreatic β-cells compared to silymarin. Also, silymarin induced a significant improvement of liver cirrhosis compared to PTX. In conclusion, the potential protective effect of PTX against β-cells deterioration could be attributed to increasing pancreatic CD39 expression and the subsequent increase of adenosine. Copyright © 2018 Elsevier B.V. All rights reserved.

GLP-1-oestrogen attenuates hyperphagia and protects from beta cell failure in diabetes-prone New Zealand obese (NZO) mice.

PubMed

Schwenk, Robert W; Baumeier, Christian; Finan, Brian; Kluth, Oliver; Brauer, Christine; Joost, Hans-Georg; DiMarchi, Richard D; Tschöp, Matthias H; Schürmann, Annette

2015-03-01

Oestrogens have previously been shown to exert beta cell protective, glucose-lowering effects in mouse models. Therefore, the recent development of a glucagon-like peptide-1 (GLP-1)-oestrogen conjugate, which targets oestrogen into cells expressing GLP-1 receptors, offers an opportunity for a cell-specific and enhanced beta cell protection by oestrogen. The purpose of this study was to compare the effects of GLP-1 and GLP-1-oestrogen during beta cell failure under glucolipotoxic conditions. Male New Zealand obese (NZO) mice were treated with daily s.c. injections of GLP-1 and GLP-1-oestrogen, respectively. Subsequently, the effects on energy homeostasis and beta cell integrity were measured. In order to clarify the targeting of GLP-1-oestrogen, transcription analyses of oestrogen-responsive genes in distinct tissues as well as microarray analyses in pancreatic islets were performed. In contrast to GLP-1, GLP-1-oestrogen significantly decreased food intake resulting in a substantial weight reduction, preserved normoglycaemia, increased glucose tolerance and enhanced beta cell protection. Analysis of hypothalamic mRNA profiles revealed elevated expression of Pomc and Leprb. In livers from GLP-1-oestrogen-treated mice, expression of lipogenic genes was attenuated and hepatic triacylglycerol levels were decreased. In pancreatic islets, GLP-1-oestrogen altered the mRNA expression to a pattern that was similar to that of diabetes-resistant NZO females. However, conventional oestrogen-responsive genes were not different, indicating rather indirect protection of pancreatic beta cells. GLP-1-oestrogen efficiently protects NZO mice against carbohydrate-induced beta cell failure by attenuation of hyperphagia. In this regard, targeted delivery of oestrogen to the hypothalamus by far exceeds the anorexigenic capacity of GLP-1 alone.

Corrosion resistant PEM fuel cell

DOEpatents

Li, Y.; Meng, W.J.; Swathirajan, S.; Harris, S.J.; Doll, G.L.

1997-04-29

The present invention contemplates a PEM fuel cell having electrical contact elements (including bipolar plates/septums) comprising a titanium nitride coated light weight metal (e.g., Al or Ti) core, having a passivating, protective metal layer intermediate the core and the titanium nitride. The protective layer forms a barrier to further oxidation/corrosion when exposed to the fuel cell`s operating environment. Stainless steels rich in Cr, Ni, and Mo are particularly effective protective interlayers. 6 figs.

Protective effect of grape seed extracts on human lymphocytes: a preliminary study.

PubMed

Szeto, Yim Tong; Lee, Kit Yee; Kalle, Wouter; Pak, Sok Cheon

2013-03-01

Grape seed extracts (GSEs) possess a broad spectrum of antioxidative properties that protects various cells from free radicals and oxidative stress. In this study, the genoprotective effect of GSE on human lymphocytic DNA was studied using standard and lysed cell comet assays. Lymphocytes from 5 healthy subjects were pretreated with GSE in different concentrations. The standard and lysed cell comet assays were performed on treated, untreated, challenged, and unchallenged cells in parallel. Cells were then subjected to an oxidant challenge induced with 5-min exposures to hydrogen peroxide. In the standard comet assay, GSE significantly diminished hydrogen-peroxide-induced DNA damage in a dose-dependent manner. In the lysed cell assay, however, the antioxidant effect was diminished at a higher GSE concentration. Data indicate that the cell membrane might play a role in limiting cellular access to antioxidants, which directly affects the genoprotective or potential pro-oxidant effect of antioxidants on human DNA. Using both standard and lysed cell comet assays in parallel could be a useful way to elucidate the mechanism of protection or damage by antioxidants.

Protective effect of carbachol postconditioning on hypoxia/reoxygenation-induced injury in human gastric epithelial cells.

PubMed

Han, Hongxia; Yang, Jun; Fei, Sujuan; Liu, Zhangbo; Zhu, Shengping; Dong, Qiuju; Gao, Zhifeng; Wang, Shihui; Zhang, Jianfu

2016-01-01

We investigated the protective effects of carbachol postconditioning (CAR-P) on acute gastric mucosal injury induced by hypoxia/reoxygenation (H/R) and its possible mechanisms. Cell viability was detected by methyl thiazolyl tetrazolium (MTT). The apoptotic cells were examined by Hoechst 33258 staining. Flow cytometric analysis, lactate dehydrogenate (LDH) release assay, immunocytochemistry, and western blotting were used to investigate the effects of CAR-P on acute gastric mucosal injury induced by H/R. The model of H/R was established by hypoxia induction(94% N2+1% O2+5% CO2 for 2 h) and reoxygenation (normoxic condition for 4 h, 8 h and 16 h). Our study observed the protective effect of carbachol postconditioning on H/R-induced injury in human gastric epithelial cell lines (hGES-1) cells, which is achieved by direct activation of vanilloid receptor subtype 1 (VR1) and production of calcitonin gene-related peptide (CGRP), and in the inhibition of cell apoptosis. In the study, we demonstrate that CAR-P has protective effects on the H/R-induced injury in hGES-1 cells, and these effects are associated with cholinergic muscarinic receptors (CMR), VR1, and extracellular signal-regulated kinase (ERK) signaling pathway. Our findings might provide a new and improved understanding of CAR-P function and an effective treatment strategy for acute gastric mucosal injury induced by H/R. Copyright © 2015 Elsevier Inc. All rights reserved.

In Vitro Model for Predicting the Protective Effect of Ultraviolet-Blocking Contact Lens in Human Corneal Epithelial Cells.

PubMed

Abengózar-Vela, Antonio; Arroyo, Cristina; Reinoso, Roberto; Enríquez-de-Salamanca, Amalia; Corell, Alfredo; González-García, María Jesús

2015-01-01

To develop an in vitro method to determine the protective effect of UV-blocking contact lenses (CLs) in human corneal epithelial (HCE) cells exposed to UV-B radiation. SV-40-transformed HCE cells were covered with non-UV-blocking CL, UV-blocking CL or not covered, and exposed to UV-B radiation. As control, HCE cells were covered with both types of CLs or not covered, but not exposed to UV-B radiation. Cell viability at 24, 48 and 72 h, after UV-B exposure and removing CLs, was determined by alamarBlue(®) assay. Percentage of live, dead and apoptotic cells was also assessed by flow cytometry after 24 h of UV-B exposure. Intracellular reactive oxygen species (ROS) production after 1 h of exposure was assessed using the dye H(2)DCF-DA. Cell viability significantly decreased, apoptotic cells and intracellular ROS production significantly increased when UVB-exposed cells were covered with non-UV-blocking CL or not covered compared to non-irradiated cells. When cells were covered with UV-blocking CL, cell viability significantly increased and apoptotic cells and intracellular ROS production did not increase compared to exposed cells. UV-B radiation induces cell death by apoptosis, increases ROS production and decreases viable cells. UV-blocking CL is able to avoid these effects increasing cell viability and protecting HCE cells from apoptosis and ROS production induced by UV-B radiation. This in vitro model is an alternative to in vivo methods to determine the protective effect of UV-blocking ophthalmic biomaterials because it is a quicker, cheaper and reliable model that avoids the use of animals.

Protective effects of vaccines against Bordetella parapertussis in a mouse intranasal challenge model.

PubMed

Komatsu, Eiji; Yamaguchi, Fuminori; Eguchi, Masahiro; Watanabe, Mineo

2010-06-17

Bordetella parapertussis causes typical whooping cough, as does Bordetella pertussis. However, current commercial vaccines are ineffective against B. parapertussis. In an effort to develop vaccines that are effective in protecting against both B. pertussis and B. parapertussis, we examined the protective effects of vaccines prepared from whole-cells and from recombinant proteins derived from B. parapertussis in a mouse intranasal challenge model. We confirmed current pertussis vaccines did not induce protective immunity against B. parapertussis in the mouse model. A whole-cell vaccine prepared from B. parapertussis induced protective immunity against B. parapertussis but not against B. pertussis, suggesting a combination of a current pertussis vaccine with a whole-cell parapertussis vaccine might prevent whooping cough caused by both species of Bordetella. We also found that filamentous hemagglutinin was a protective antigen of B. parapertussis. Our observations should lead to the development of new pertussis vaccines that can control the two prevalent forms of whooping cough.

Improved mitochondrial function underlies the protective effect of pirfenidone against tubulointerstitial fibrosis in 5/6 nephrectomized rats.

PubMed

Chen, Jun-Feng; Liu, Hong; Ni, Hai-Feng; Lv, Lin-Li; Zhang, Ming-Hui; Zhang, Ai-Hua; Tang, Ri-Ning; Chen, Ping-Sheng; Liu, Bi-Cheng

2013-01-01

Dysfunctional mitochondria participate in the progression of chronic kidney disease (CKD). Pirfenidone is a newly identified anti-fibrotic drug. However, its mechanism remains unclear. Mitochondrial dysfunction is an early event that occurs prior to the onset of renal fibrosis. In this context, we investigated the protective effect of pirfenidone on mitochondria and its relevance to apoptosis and oxidative stress in renal proximal tubular cells. A remnant kidney rat model was established. Human renal proximal tubular epithelial cells (HK2) using rotenone, a mitochondrial respiratory chain complex Ι inhibitor were further investigated in vitro to examine the mitochondrial protective effect of pirfenidone. Pirfenidone protected mitochondrial structures and functions by stabilizing the mitochondrial membrane potential, maintaining ATP production and improving the mitochondrial DNA (mtDNA) copy number. Pirfenidone decreased tubular cell apoptosis by inhibiting the mitochondrial apoptotic signaling pathway. Pirfenidone also reduced oxidative stress by enhancing manganese superoxide dismutase (Mn-SOD) and inhibiting intracellular reactive oxygen species (ROS) generation, which suggested that the anti-oxidant effects occurred at least partially via the mitochondrial pathway. Pirfenidone may be effective prior to the onset of renal fibrosis because this drug exerts its anti-fibrotic effect by protection of mitochondria in renal proximal tubular cells.

Improved Mitochondrial Function Underlies the Protective Effect of Pirfenidone against Tubulointerstitial Fibrosis in 5/6 Nephrectomized Rats

PubMed Central

Chen, Jun-Feng; Liu, Hong; Ni, Hai-Feng; Lv, Lin-Li; Zhang, Ming-Hui; Zhang, Ai-Hua; Tang, Ri-Ning; Chen, Ping-Sheng; Liu, Bi-Cheng

2013-01-01

Dysfunctional mitochondria participate in the progression of chronic kidney disease (CKD). Pirfenidone is a newly identified anti-fibrotic drug. However, its mechanism remains unclear. Mitochondrial dysfunction is an early event that occurs prior to the onset of renal fibrosis. In this context, we investigated the protective effect of pirfenidone on mitochondria and its relevance to apoptosis and oxidative stress in renal proximal tubular cells. A remnant kidney rat model was established. Human renal proximal tubular epithelial cells (HK2) using rotenone, a mitochondrial respiratory chain complex Ι inhibitor were further investigated in vitro to examine the mitochondrial protective effect of pirfenidone. Pirfenidone protected mitochondrial structures and functions by stabilizing the mitochondrial membrane potential, maintaining ATP production and improving the mitochondrial DNA (mtDNA) copy number. Pirfenidone decreased tubular cell apoptosis by inhibiting the mitochondrial apoptotic signaling pathway. Pirfenidone also reduced oxidative stress by enhancing manganese superoxide dismutase (Mn-SOD) and inhibiting intracellular reactive oxygen species (ROS) generation, which suggested that the anti-oxidant effects occurred at least partially via the mitochondrial pathway. Pirfenidone may be effective prior to the onset of renal fibrosis because this drug exerts its anti-fibrotic effect by protection of mitochondria in renal proximal tubular cells. PMID:24349535

Influence of metal ions on flavonoid protection against asbestos-induced cell injury.

PubMed

Kostyuk, V A; Potapovich, A I; Vladykovskaya, E N; Korkina, L G; Afanas'ev, I B

2001-01-01

Influence of metal ions (Fe2+, Fe3+, Cu2+, Zn2+) on the protective effect of rutin, dihydroquercetin, and green tea epicatechins against in vitro asbestos-induced cell injury was studied. Metals have been found to increase the capacity of rutin and dihydroquercetin to protect peritoneal macrophages against chrysotile asbestos-induced injury. The data presented here show that this effect is due to the formation of flavonoid metal complexes, which turned out to be more effective radical scavengers than uncomplexed flavonoids. At the same time epicatechins and their metal complexes have similar antiradical properties and protective capacities against the asbestos induced injury of macrophages. Metal complexes of all flavonoids were found to be considerably more potent than parent flavonoids in protecting red blood cells against asbestos-induced injury. It was also found that the metal complexes of all flavonoids were absorbed by chrysotile asbestos fibers considerably better than uncomplexed compounds and probably for this reason flavonoid metal complexes have better protective properties against asbestos induced hemolysis. Thus, the results of the present study show that flavonoid metal complexes may be effective therapy for the inflammatory response associated with the inhalation of asbestos fiber. The advantage of their application could be the strong increase in ROS scavenging by flavonoids and finally a better cell protection under the conditions of cellular oxidative stress.

Collagen gel protects L929 cells from TNFα-induced death by activating NF-κB.

PubMed

Wang, Hong-Ju; Li, Meng-Qi; Liu, Wei-Wei; Hayashi, Toshihiko; Fujisaki, Hitomi; Hattori, Shunji; Tashiro, Shin-Ichi; Onodera, Satoshi; Ikejima, Takashi

2017-09-01

Type I collagen is one of the most abundant components of extracellular matrix. We previously illustrated that murine fibrosarcoma L929 cells grew well on type I collagen gel and escaped from TNFα-induced cell death. In this study, we investigated the mechanism underlying the protective effect of collagen gel. We used western blot, confocal microscopy, MTT assay and flow cytometry by introducing fluorescence staining to determine the expression levels of nuclear factor kappa B (NF-κB), inhibitory ratio and autophagy. L929 cells on collagen gel showed higher expression of NF-κB in the nucleus. Inhibition of NF-κB with pyrrolidine dithiocarbamate hydrochloride (PDTC) or knockdown by NF-κB-siRNA canceled the protective effect of collagen gel on L929 cells from TNFα-induced death, suggesting for the role of NF-κB in the protection from cell death. We found a new aspect of the effect of PDTC on L929 cells cultured on collagen gel. PDTC alone without TNFα induced apoptosis in the L929 cells cultured on collagen gel but not the cells on plastic dish. The apoptosis induction of the L929 cells cultured on collagen gel with PDTC was repressed by inhibiting autophagy with chloroquine, an autophagy inhibitor, suggesting that autophagy contributes to the death induced by the treatment with PDTC. Possible underlying mechanism of this finding is discussed. NF-κB played an important role in protecting the L929 cells cultured on collagen gel from TNFα-induced death.

Protective effects of a freeze-dried extract of vegetables and fruits on the hydroxyl radical-mediated oxidative damage of DNA and decrease of erythrocytes deformability.

PubMed

Wang, Hsiao-Ning; Liu, Tsan-Zon; Chen, Ya-Lei; Shiuan, David

2007-01-01

The protective effects of a freeze-dried extracts of vegetables and fruits (BauYuan; BY) on the hydroxyl radical-mediated DNA strand breakages and the structural integrity of human red blood cells (RBCs) were investigated. First, the supercoiled plasmid (pEGFP-C1) DNA was subjected to oxidation damage by an ascorbate-fortified Fenton reaction and the protective effects were analyzed by agarose gel electrophoresis. In the absence of BY extracts, exposure of the high-throughput .OH-generating system (Fe2+ concentration >1.0 microM) caused a complete fragmentation of DNA. Supplementation of BY extract (1 mg/mL) to the plasmid DNA prior to the exposure could prevent it significantly. In contrast, as the plasmid exposed to a low-grade .OH-generating system (Fe2+<0.1 microM), the BY extract (1 mg/mL) provided an almost complete protection. Next, the cell deformabilities were measured to assess the protection effects of various BY extracts on human erythrocytes exposed to the oxidative insults. We found that both the aqueous extract and the organic solvent-derived extracts could strongly protect human RBCs from the reactive oxygen species (ROS)-mediated decrease in the deformability indices. The results implicated that the BY extracts could effectively protect the cell membrane integrity via scavenging ROS which enabling RBCs to maintain a balance of water content and surface area to prevent the drop of cell deformability.

Protection against Recurrent Stroke with Resveratrol: Endothelial Protection

PubMed Central

Clark, Darren; Tuor, Ursula I.; Thompson, Roger; Institoris, Adam; Kulynych, Angela; Zhang, Xu; Kinniburgh, David W.; Bari, Ferenc; Busija, David W.; Barber, Philip A.

2012-01-01

Despite increased risk of a recurrent stroke following a minor stroke, information is minimal regarding the interaction between injurious mild cerebral ischemic episodes and the possible treatments which might be effective. The aim of the current study was to investigate recurrent ischemic stroke and whether resveratrol, a nutritive polyphenol with promising cardio- and neuro- protective properties, could ameliorate the associated brain damage. Experiments in adult rats demonstrated that a mild ischemic stroke followed by a second mild cerebral ischemia exacerbated brain damage, and, daily oral resveratrol treatment after the first ischemic insult reduced ischemic cell death with the recurrent insult (P<0.002). Further investigation demonstrated reduction of both inflammatory changes and markers of oxidative stress in resveratrol treated animals. The protection observed with resveratrol treatment could not be explained by systemic effects of resveratrol treatment including effects either on blood pressure or body temperature measured telemetrically. Investigation of resveratrol effects on the blood-brain barrier in vivo demonstrated that resveratrol treatment reduced blood-brain barrier disruption and edema following recurrent stroke without affecting regional cerebral blood flow. Investigation of the mechanism in primary cell culture studies demonstrated that resveratrol treatment significantly protected endothelial cells against an in vitro ‘ischemia’ resulting in improved viability against oxygen and glucose deprivation (39.6±6.6% and 81.3±9.5% in vehicle and resveratrol treated cells, respectively). An inhibition of nitric oxide synthesis did not prevent the improved cell viability following oxygen glucose deprivation but SIRT-1 inhibition with sirtinol partially blocked the protection (P<0.001) suggesting endothelial protection is to some extent SIRT-1 dependent. Collectively, the results support that oral resveratrol treatment provides a low risk strategy to protect the brain from enhanced damage produced by recurrent stroke which is mediated in part by a protective effect of resveratrol on the endothelium of the cerebrovasculature. PMID:23082218

Protective Effect of Coriolus versicolor Cultivated in Citrus Extract Against Nitric Oxide-Induced Apoptosis in Human Neuroblastoma SK-N-MC Cells

PubMed Central

Kim, Byung-Chul; Kim, Youn-Sub; Lee, Jin-Woo; Seo, Jin-Hee; Ji, Eun-Sang; Lee, Hyejung; Park, Yong-Il

2011-01-01

Nitric oxide (NO) is a reactive free radical and a messenger molecule in many physiological functions. However, excessive NO is believed to be a mediator of neurotoxicity. The medicinal plant Coriolus versicolor is known to possess anti-tumor and immune-potentiating activities. In this study, we investigated whether Coriolus versicolor possesses a protective effect against NO donor sodium nitroprusside (SNP)-induced apoptosis in the human neuroblastoma cell line SK-N-MC. We utilized 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry, 4,6-diamidino-2-phenylindole (DAPI) staining, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay, DNA fragmentation assay, reverse transcription-polymerase chain reaction (RT-PCR), Western blot analysis, and caspase-3 enzyme activity assay in SK-N-MC cells. MTT assay showed that SNP treatment significantly reduces the viability of cells, and the viabilities of cells pre-treated with the aqueous extract of Coriolus versicolor cultivated in citrus extract (CVEcitrus) was increased. However, aqueous extract of Coriolus versicolor cultivated in synthetic medium (CVEsynthetic) showed no protective effect and aqueous citrus extract (CE) had a little protective effect. The cell treated with SNP exhibited several apoptotic features, while those pre-treated for 1 h with CVEcitrus prior to SNP expose showed reduced apoptotic features. The cells pre-treated for 1 h with CVEcitrus prior to SNP expose inhibited p53 and Bax expressions and caspase-3 enzyme activity up-regulated by SNP. We showed that CVEcitrus exerts a protective effect against SNP-induced apoptosis in SK-N-MC cells. Our study suggests that CVEcitrus has therapeutic value in the treatment of a variety of NO-induced brain diseases. PMID:22110367

Protective Effect of Coriolus versicolor Cultivated in Citrus Extract Against Nitric Oxide-Induced Apoptosis in Human Neuroblastoma SK-N-MC Cells.

PubMed

Kim, Byung-Chul; Kim, Youn-Sub; Lee, Jin-Woo; Seo, Jin-Hee; Ji, Eun-Sang; Lee, Hyejung; Park, Yong-Il; Kim, Chang-Ju

2011-06-01

Nitric oxide (NO) is a reactive free radical and a messenger molecule in many physiological functions. However, excessive NO is believed to be a mediator of neurotoxicity. The medicinal plant Coriolus versicolor is known to possess anti-tumor and immune-potentiating activities. In this study, we investigated whether Coriolus versicolor possesses a protective effect against NO donor sodium nitroprusside (SNP)-induced apoptosis in the human neuroblastoma cell line SK-N-MC. We utilized 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry, 4,6-diamidino-2-phenylindole (DAPI) staining, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay, DNA fragmentation assay, reverse transcription-polymerase chain reaction (RT-PCR), Western blot analysis, and caspase-3 enzyme activity assay in SK-N-MC cells. MTT assay showed that SNP treatment significantly reduces the viability of cells, and the viabilities of cells pre-treated with the aqueous extract of Coriolus versicolor cultivated in citrus extract (CVE(citrus)) was increased. However, aqueous extract of Coriolus versicolor cultivated in synthetic medium (CVE(synthetic)) showed no protective effect and aqueous citrus extract (CE) had a little protective effect. The cell treated with SNP exhibited several apoptotic features, while those pre-treated for 1 h with CVE(citrus) prior to SNP expose showed reduced apoptotic features. The cells pre-treated for 1 h with CVE(citrus) prior to SNP expose inhibited p53 and Bax expressions and caspase-3 enzyme activity up-regulated by SNP. We showed that CVE(citrus) exerts a protective effect against SNP-induced apoptosis in SK-N-MC cells. Our study suggests that CVE(citrus) has therapeutic value in the treatment of a variety of NO-induced brain diseases.

Mitochondria-Division Inhibitor 1 Protects Against Amyloid-β induced Mitochondrial Fragmentation and Synaptic Damage in Alzheimer's Disease.

PubMed

Reddy, P Hemachandra; Manczak, Maria; Yin, XiangLing

2017-01-01

The purpose our study was to determine the protective effects of mitochondria division inhibitor 1 (Mdivi1) in Alzheimer's disease (AD). Mdivi1 is hypothesized to reduce excessive fragmentation of mitochondria and mitochondrial dysfunction in AD neurons. Very little is known about whether Mdivi1 can confer protective effects in AD. In the present study, we sought to determine the protective effects of Mdivi1 against amyloid-β (Aβ)- and mitochondrial fission protein, dynamin-related protein 1 (Drp1)-induced excessive fragmentation of mitochondria in AD progression. We also studied preventive (Mdivi1+Aβ42) and intervention (Aβ42+Mdivi1) effects against Aβ42 in N2a cells. Using real-time RT-PCR and immunoblotting analysis, we measured mRNA and protein levels of mitochondrial dynamics, mitochondrial biogenesis, and synaptic genes. We also assessed mitochondrial function by measuring H2O2, lipid peroxidation, cytochrome oxidase activity, and mitochondrial ATP. MTT assays were used to assess the cell viability. Aβ42 was found to impair mitochondrial dynamics, lower mitochondrial biogenesis, lower synaptic activity, and lower mitochondrial function. On the contrary, Mdivi1 enhanced mitochondrial fusion activity, lowered fission machinery, and increased biogenesis and synaptic proteins. Mitochondrial function and cell viability were elevated in Mdivi1-treated cells. Interestingly, Mdivi1 pre- and post-treated cells treated with Aβ showed reduced mitochondrial dysfunction, and maintained cell viability, mitochondrial dynamics, mitochondrial biogenesis, and synaptic activity. The protective effects of Mdivi1 were stronger in N2a+Aβ42 pre-treated with Mdivi1, than in N2a+Aβ42 cells than Mdivi1 post-treated cells, indicating that Mdivi1 works better in prevention than treatment in AD like neurons.

IL-4Rα-Associated Antigen Processing by B Cells Promotes Immunity in Nippostrongylus brasiliensis Infection

PubMed Central

Hoving, Jennifer C.; Nieuwenhuizen, Natalie; McSorley, Henry J.; Ndlovu, Hlumani; Bobat, Saeeda; Kimberg, Matti; Kirstein, Frank; Cutler, Anthony J.; DeWals, Benjamin; Cunningham, Adam F.; Brombacher, Frank

2013-01-01

In this study, B cell function in protective TH2 immunity against N. brasiliensis infection was investigated. Protection against secondary infection depended on IL-4Rα and IL-13; but not IL-4. Protection did not associate with parasite specific antibody responses. Re-infection of B cell-specific IL-4Rα−/− mice resulted in increased worm burdens compared to control mice, despite their equivalent capacity to control primary infection. Impaired protection correlated with reduced lymphocyte IL-13 production and B cell MHC class II and CD86 surface expression. Adoptive transfer of in vivo N. brasiliensis primed IL-4Rα expressing B cells into naïve BALB/c mice, but not IL-4Rα or IL-13 deficient B cells, conferred protection against primary N. brasiliensis infection. This protection required MHC class II compatibility on B cells suggesting cognate interactions by B cells with CD4+ T cells were important to co-ordinate immunity. Furthermore, the rapid nature of these protective effects by B cells suggested non-BCR mediated mechanisms, such as via Toll Like Receptors, was involved, and this was supported by transfer experiments using antigen pulsed Myd88−/− B cells. These data suggest TLR dependent antigen processing by IL-4Rα-responsive B cells producing IL-13 contribute significantly to CD4+ T cell-mediated protective immunity against N. brasiliensis infection. PMID:24204255

[HPLC specific chromatogram spectrum-effect relationship for Shuanghuanglian on MDCK cell injury induced by influenza A virus (H1N1)].

PubMed

Liu, Ting; Wang, Hai-dan; Di, Liu-qing; Kang, An; Zhao, Xiao-li; Zhu, Xuan-xuan; Li, Jun-song

2015-11-01

To establish HPLC specific chromatogram and its correlation with the protection effect of Shuanghuanglian on MDCK (Madin-Darby canine kidney) cell injury induced by influenza A virus( H1N1). Nine recipes of Shuanghuanglian based on the official prescription were prepared according to orthogonal test for HPLC analysis and MDCK cells protection experiment separately (cytopathic effect (CPE) method was used for observing the virus infectivity and MTT staining results were used as the determining indexes for drug concentration selection and analyzing cell viability). The results suggested that all the other Shuang-Huang-Lian recipes except recipe1 demonstrate protecting effect on MDCK cell injury induced by influenza A virus (P < 0.01, P < 0.001). Stepwise regression analysis was used for analyzing the relationships between HPLC fingerprint and the protecting effect of Shuanghuanglian on influenza A virus induced MDCK cell injury. Peak 2, 3, 6, 8 and 12 were found to be strongly related with anti-influenza A virus efficacy. Stepwise regression analysis of recipes data and efficacy data showed that Lonicerae Japonicae Flos and Forsythiae Fructus were positively associated with the protecting effect of cells injury. From HPLC fingerprints, we found that peak 2, 3, 12 were from Lonicerae Japonicae Flos and peak 6, 8 were from Forsythiae Fructus. Four peaks were identified through comparing the retention time between the standard and Shuanghuanglian recipes, and they were chlorogenicacid, cryptochlorogenic acid, forsythoside B and 3,4-dicaffeoylquinic acid respectively. Caffeic acid derivatives in Lonicerae Japonicae Flos and Forsythiae Fructus were found to be greatly correlated with anti-influenza A virus efficacy and maybe the substance basis of Shuanghuanglian.

Estradiol is a protective factor in the adult and aging brain: understanding of mechanisms derived from in vivo and in vitro studies.

PubMed

Wise, P M; Dubal, D B; Wilson, M E; Rau, S W; Böttner, M; Rosewell, K L

2001-11-01

We have shown that 17beta-estradiol exerts profound protective effects against stroke-like ischemic injury in female rats. These effects are evident using physiological levels of estradiol replacement in ovariectomized rats and require hormone treatment prior to the time of injury. The protective actions of estradiol appear to be most prominent in the cerebral cortex, where cell death is not apparent until at least 4 h after the initiation of ischemic injury and where cell death is thought to be apoptotic in nature. Middle-aged rats remain equally responsive to the protective actions of estradiol. The maintenance of responsiveness of the cerebral cortex to the neuroprotective actions of estradiol was unexpected since responsiveness of the hypothalamus to estradiol decreases dramatically by the time animals are middle-aged. We believe that the protective actions of estradiol require the estrogen receptor-alpha, since estradiol does not protect in estrogen receptor-alpha knockout mice. We have also implemented a method of culturing cerebral cortical explants to assess the protective effects of estradiol in vitro. This model exhibits remarkable parallelisms with our in vivo model of brain injury. We have found that 17beta-estradiol decreases the extent of cell death and that this protective effect requires hormone pretreatment. Finally, 17alpha-estradiol, which does not interact effectively with the estrogen receptor, does not protect; and addition of ICI 182,780, an estrogen receptor antagonist, blocks the protective actions of estradiol. We have begun to explore the molecular and cellular mechanisms of estradiol-mediated protection. In summary, our findings demonstrate that estradiol exerts powerful protective effects both in vivo and in vitro and suggest that these actions are mediated by estrogen receptors.

The Atypical Antipsychotic Agent, Clozapine, Protects Against Corticosterone-Induced Death of PC12 Cells by Regulating the Akt/FoxO3a Signaling Pathway.

PubMed

Zeng, Zhiwen; Wang, Xue; Bhardwaj, Sanjeev K; Zhou, Xuanhe; Little, Peter J; Quirion, Remi; Srivastava, Lalit K; Zheng, Wenhua

2017-07-01

Schizophrenia is one of the most severe psychiatric disorders. Increasing evidence implicates that neurodegeneration is a component of schizophrenia pathology and some atypical antipsychotics are neuroprotective and successful in slowing the progressive morphological brain changes. As an antipsychotic agent, clozapine has superior and unique effects, but the intracellular signaling pathways that mediate clozapine action remain to be elucidated. The phosphatidylinositol-3-kinase/protein kinase B/Forkhead box O3 (PI3K/Akt/FoxO3a) pathway is crucial for neuronal survival. However, little information is available regarding this pathway with clozapine. In the present study, we investigated the protective effect of clozapine on the PC12 cells against corticosterone toxicity. Our results showed that corticosterone decreases the phosphorylation of Akt and FoxO3a, leading to the nuclear localization of FoxO3a and the apoptosis of PC12 cells, while clozapine concentration dependently protected PC12 cells against corticosterone insult. Pathway inhibitors studies displayed that the protective effect of clozapine was reversed by LY294002 and wortmannin, two PI3K inhibitors, or Akt inhibitor VIII although several other inhibitors had no effect. The shRNA knockdown results displayed that downregulated Akt1 or FoxO3a attenuated the protective effect of clozapine. Western blot analyses revealed that clozapine induced the phosphorylation of Akt and FoxO3a by the PI3K/Akt pathway and reversed the reduction of the phosphorylated Akt and FoxO3a and the nuclear translocation of FoxO3a evoked by corticosterone. Together, our data indicates that clozapine protects PC12 cells against corticosterone-induced cell death by modulating activity of the PI3K/Akt/FoxO3a pathway.

Cytoprotective dibenzoylmethane derivatives protect cells from oxidative stress-induced necrotic cell death.

PubMed

Hegedűs, Csaba; Lakatos, Petra; Kiss-Szikszai, Attila; Patonay, Tamás; Gergely, Szabolcs; Gregus, Andrea; Bai, Péter; Haskó, György; Szabó, Éva; Virág, László

2013-06-01

Screening of a small in-house library of 1863 compounds identified 29 compounds that protected Jurkat cells from hydrogen peroxide-induced cytotoxicity. From the cytoprotective compounds eleven proved to possess antioxidant activity (ABTS radical scavenger effect) and two were found to inhibit poly(ADP-ribosyl)ation (PARylation), a cytotoxic pathway operating in severely injured cells. Four cytoprotective dibenzoylmethane (DBM) derivatives were investigated in more detail as they did not scavenge hydrogen peroxide nor did they inhibit PARylation. These compounds protected cells from necrotic cell death while caspase activation, a parameter of apoptotic cell death was not affected. Hydrogen peroxide activated extracellular signal regulated kinase (ERK1/2) and p38 MAP kinases but not c-Jun N-terminal kinase (JNK). The cytoprotective DBMs suppressed the activation of Erk1/2 but not that of p38. Cytoprotection was confirmed in another cell type (A549 lung epithelial cells), indicating that the cytoprotective effect is not cell type specific. In conclusion we identified DBM analogs as a novel class of cytoprotective compounds inhibiting ERK1/2 kinase and protecting from necrotic cell death by a mechanism independent of poly(ADP-ribose) polymerase inhibition. Copyright © 2013 Elsevier Ltd. All rights reserved.

The protective effect of niacinamide on CHO AA8 cell line against ultraviolet radiation in the context of main cytoskeletal proteins.

PubMed

Izdebska, Magdalena; Hałas-Wiśniewska, Marta; Adamczyk, Iwona; Lewandowska, Ismena; Kwiatkowska, Iga; Gagat, Maciej; Grzanka, Alina

2018-03-13

Niacinamide is a stable and water-soluble form of vitamin B3, a valuable and versatile cosmetic ingredient, which is well absorbed and tolerated by the skin. A large body of literature has reported on the antioxidant and cell repair properties of niacinamide. Therefore, it has been shown to be useful in the protection of the skin against ultraviolet B (UVB) radiation and free radicals. Despite numerous hypotheses on the mechanism of vitamin B3, its protective effects have not yet been fully elucidated. The aim of the study was to determine the protective effects of niacinamide on CHO AA8 cell line against UVB radiation. We assessed the following factors: cell death, cell cycle phase distributions, reorganization of main cytoskeletal proteins, such as F-actin, vimentin and β-tubulin, and also alterations at the ultrastructural level. The material used for our research was Chinese hamster ovary cell line (CHO AA8). We used 4 research groups: 1) control cells; 2) cells treated with niacinamide; 3) cells exposed to UV radiation; and 4) cells co-incubated with niacinamide and next exposed to ultraviolet. The cell death and cell cycle were evaluated by a Tali® based-image cytometer. A fluorescence microscope was used to assess the reorganization of cytoskeletal proteins, whereas a transmission electron microscope enabled the evaluation of the alterations at the ultrastructural level of cells. We showed that UV-induced apoptosis and cell cycle distributions during treatment with niacinamide resulted in a non-statistical significance in cell survival and no significant changes in the morphology and cytoskeleton in comparison to the control group. In turn, a combination of both factors led to an increase in the population of live cells and a decreased level of apoptotic cells in comparison to UV-exposed cells. Our results confirmed the harmful effects of UV radiation on CHO AA8 cell line. Furthermore, niacinamide can protect cells against these factors, and the mechanism of action may be related to the stabilization of the cell cytoskeleton.

Titan Cells Confer Protection from Phagocytosis in Cryptococcus neoformans Infections

PubMed Central

Okagaki, Laura H.

2012-01-01

The human fungal pathogen Cryptococcus neoformans produces an enlarged “titan” cell morphology when exposed to the host pulmonary environment. Titan cells exhibit traits that promote survival in the host. Previous studies showed that titan cells are not phagocytosed and that increased titan cell production in the lungs results in reduced phagocytosis of cryptococcal cells by host immune cells. Here, the effect of titan cell production on host-pathogen interactions during early stages of pulmonary cryptococcosis was explored. The relationship between titan cell production and phagocytosis was found to be nonlinear; moderate increases in titan cell production resulted in profound decreases in phagocytosis, with significant differences occurring within the first 24 h of the infection. Not only were titan cells themselves protected from phagocytosis, but titan cell formation also conferred protection from phagocytosis to normal-size cryptococcal cells. Large particles introduced into the lungs were not phagocytosed, suggesting the large size of titan cells protects against phagocytosis. The presence of large particles was unable to protect smaller particles from phagocytosis, revealing that titan cell size alone is not sufficient to provide the observed cross-protection of normal-size cryptococcal cells. These data suggest that titan cells play a critical role in establishment of the pulmonary infection by promoting the survival of the entire population of cryptococcal cells. PMID:22544904

Titan cells confer protection from phagocytosis in Cryptococcus neoformans infections.

PubMed

Okagaki, Laura H; Nielsen, Kirsten

2012-06-01

The human fungal pathogen Cryptococcus neoformans produces an enlarged "titan" cell morphology when exposed to the host pulmonary environment. Titan cells exhibit traits that promote survival in the host. Previous studies showed that titan cells are not phagocytosed and that increased titan cell production in the lungs results in reduced phagocytosis of cryptococcal cells by host immune cells. Here, the effect of titan cell production on host-pathogen interactions during early stages of pulmonary cryptococcosis was explored. The relationship between titan cell production and phagocytosis was found to be nonlinear; moderate increases in titan cell production resulted in profound decreases in phagocytosis, with significant differences occurring within the first 24 h of the infection. Not only were titan cells themselves protected from phagocytosis, but titan cell formation also conferred protection from phagocytosis to normal-size cryptococcal cells. Large particles introduced into the lungs were not phagocytosed, suggesting the large size of titan cells protects against phagocytosis. The presence of large particles was unable to protect smaller particles from phagocytosis, revealing that titan cell size alone is not sufficient to provide the observed cross-protection of normal-size cryptococcal cells. These data suggest that titan cells play a critical role in establishment of the pulmonary infection by promoting the survival of the entire population of cryptococcal cells.

Far infrared radiation promotes rabbit renal proximal tubule cell proliferation and functional characteristics, and protects against cisplatin-induced nephrotoxicity.

PubMed

Chiang, I-Ni; Pu, Yeong-Shiau; Huang, Chao-Yuan; Young, Tai-Horng

2017-01-01

Far infrared radiation, a subdivision of the electromagnetic spectrum, is beneficial for long-term tissue healing, anti-inflammatory effects, growth promotion, sleep modulation, acceleration of microcirculation, and pain relief. We investigated if far infrared radiation is beneficial for renal proximal tubule cell cultivation and renal tissue engineering. We observed the effects of far infrared radiation on renal proximal tubules cells, including its effects on cell proliferation, gene and protein expression, and viability. We also examined the protective effects of far infrared radiation against cisplatin, a nephrotoxic agent, using the human proximal tubule cell line HK-2. We found that daily exposure to far infrared radiation for 30 min significantly increased rabbit renal proximal tubule cell proliferation in vitro, as assessed by MTT assay. Far infrared radiation was not only beneficial to renal proximal tubule cell proliferation, it also increased the expression of ATPase Na+/K+ subunit alpha 1 and glucose transporter 1, as determined by western blotting. Using quantitative polymerase chain reaction, we found that far infrared radiation enhanced CDK5R1, GNAS, NPPB, and TEK expression. In the proximal tubule cell line HK-2, far infrared radiation protected against cisplatin-mediated nephrotoxicity by reducing apoptosis. Renal proximal tubule cell cultivation with far infrared radiation exposure resulted in better cell proliferation, significantly higher ATPase Na+/K+ subunit alpha 1 and glucose transporter 1 expression, and significantly enhanced expression of CDK5R1, GNAS, NPPB, and TEK. These results suggest that far infrared radiation improves cell proliferation and differentiation. In HK-2 cells, far infrared radiation mediated protective effects against cisplatin-induced nephrotoxicity by reducing apoptosis, as indicated by flow cytometry and caspase-3 assay.

Protective Effects of Black Rice Extracts on Oxidative Stress Induced by tert-Butyl Hydroperoxide in HepG2 Cells

PubMed Central

Lee, Seon-Mi; Choi, Youngmin; Sung, Jeehye; Kim, Younghwa; Jeong, Heon-Sang; Lee, Junsoo

2014-01-01

Black rice contains many biologically active compounds. The aim of this study was to investigate the protective effects of black rice extracts (whole grain extract, WGE and rice bran extract, RBE) on tert-butyl hydroperoxide (TBHP)-induced oxidative injury in HepG2 cells. Cellular reactive oxygen species (ROS), antioxidant enzyme activities, malondialdehyde (MDA) and glutathione (GSH) concentrations were evaluated as biomarkers of cellular oxidative status. Cells pretreated with 50 and 100 μg/mL of WGE or RBE were more resistant to oxidative stress in a dose-dependent manner. The highest WGE and BRE concentrations enhanced GSH concentrations and modulated antioxidant enzyme activities (glutathione reductase, glutathione-S-transferase, catalase, and superoxide dismutase) compared to TBHP-treated cells. Cells treated with RBE showed higher protective effect compared to cells treated with WGE against oxidative insult. Black rice extracts attenuated oxidative insult by inhibiting cellular ROS and MDA increase and by modulating antioxidant enzyme activities in HepG2 cells. PMID:25580401

Gingerol Synergizes the Cytotoxic Effects of Doxorubicin against Liver Cancer Cells and Protects from Its Vascular Toxicity.

PubMed

Al-Abbasi, Fahad A; Alghamdi, Eman A; Baghdadi, Mohammed A; Alamoudi, Abdulmohsin J; El-Halawany, Ali M; El-Bassossy, Hany M; Aseeri, Ali H; Al-Abd, Ahmed M

2016-07-08

Hydroxyphenylalkanes and diarylheptanoids possess potential therapeutic value in different pathophysiological conditions, such as malignancy. In the current study, naturally isolated hydroxyphenylalkane and diarylheptanoid compounds were investigated for potential chemo-modulatory effects in addition to potential vascular protective roles with doxorubicin. Diarylheptanoids showed stronger antioxidant effects, in comparison to hydroxyphenylalkanes, as demonstrated by DPPH assay and amelioration of CCl₄-induced disturbed intracellular GSH/GSSG balance. Shogaol and 4'-methoxygingerol showed considerable cytotoxic effects against HCT116, HeLa, HepG2 and MCF7 cells, with IC50 values ranging from 3.1 to 19.4 µM. Gingerol significantly enhanced the cytotoxic profile of doxorubicin against HepG₂ and Huh7, cells decreasing its IC50s by 10- and 4-fold, respectively. Cell cycle distribution was studied using DNA cytometry. Doxorubicin alone induced cell accumulation at S-phase and G₂/M-phase, while in combination with gingerol it significantly induced cell cycle arrest at the G₂/M-phase. Additionally, the vascular protective effect of gingerol against doxorubicin (10 µM) was examined on isolated aortic rings. Co-incubation with 6-gingerol (30 µM) completely blocked the exaggerated vasoconstriction and impaired vascular relaxation induced by doxorubicin. In conclusion, despite its relatively weak antioxidant properties, gingerol protected from DOX-induced vascular damage, apparently not through a ROS scavenging mechanism. Besides, gingerol synergized the cytotoxic effects of DOX against liver cancer cells without influencing the cellular pharmacokinetics.

Induction of CD8 T Cell Heterologous Protection by a Single Dose of Single-Cycle Infectious Influenza Virus

PubMed Central

Baker, Steven F.; Martínez-Sobrido, Luis

2014-01-01

ABSTRACT The effector functions of specific CD8 T cells are crucial in mediating influenza heterologous protection. However, new approaches for influenza vaccines that can trigger effective CD8 T cell responses have not been extensively explored. We report here the generation of single-cycle infectious influenza virus that lacks a functional hemagglutinin (HA) gene on an X31 genetic background and demonstrate its potential for triggering protective CD8 T cell immunity against heterologous influenza virus challenge. In vitro, X31-sciIV can infect MDCK cells, but infectious virions are not produced unless HA is transcomplemented. In vivo, intranasal immunization with X31-sciIV does not cause any clinical symptoms in mice but generates influenza-specific CD8 T cells in lymphoid (mediastinal lymph nodes and spleen) and nonlymphoid tissues, including lung and bronchoalveolar lavage fluid, as measured by H2-Db NP366 and PA224 tetramer staining. In addition, a significant proportion of X31-sciIV-induced antigen-specific respiratory CD8 T cells expressed VLA-1, a marker that is associated with heterologous influenza protection. Further, these influenza-specific CD8 T cells produce antiviral cytokines when stimulated with NP366 and PA224 peptides, indicating that CD8 T cells triggered by X31-sciIV are functional. When challenged with a lethal dose of heterologous PR8 virus, X31-sciIV-primed mice were fully protected from death. However, when CD8 T cells were depleted after priming or before priming, mice could not effectively control virus replication or survive the lethal challenge, indicating that X31-sciIV-induced memory CD8 T cells mediate the heterologous protection. Thus, our results demonstrate the potential for sciIV as a CD8 T cell-inducing vaccine. IMPORTANCE One of the challenges for influenza prevention is the existence of multiple influenza virus subtypes and variants and the fact that new strains can emerge yearly. Numerous studies have indicated that the effector functions of specific CD8 T cells are crucial in mediating influenza heterologous protection. However, influenza vaccines that can trigger effective CD8 T cell responses for heterologous protection have not been developed. We report here the generation of an X31 (H3N2) virus-derived single-cycle infectious influenza virus, X31-sciIV. A one-dose immunization with X31-sciIV is capable of inducing functional influenza virus-specific CD8 T cells that can be recruited into respiratory tissues and provide protection against lethal heterologous challenge. Without these cells, protection against lethal challenge was essentially lost. Our data indicate that an influenza vaccine that primarily relies on CD8 T cells for protection could be developed. PMID:25100831

Protective effect of biological response modifiers on murine cytomegalovirus infection.

PubMed Central

Ebihara, K; Minamishima, Y

1984-01-01

Pretreatment with two biological response modifiers (BRM), OK-432 and PS-K, protected mice from lethal infection by murine cytomegalovirus (MCMV). This was evidenced by an increase in 50% lethal doses and a decrease in titers of infectious viruses replicated in the liver and spleen. Spleen cells from the BRM-treated mice augmented the natural killer (NK) cell activity and suppressed the replication of MCMV in vitro. During MCMV infection, the NK cell activity of the spleen cells was maintained at a high level in the BRM-treated mice, whereas it was severely impaired in untreated mice. The BRM-induced protection was nullified by concomitant administration of antiasialo GM1 antibody. Interferon was neither induced by BRM treatment nor enhanced in BRM-pretreated and MCMV-infected mice. Thus, the protective effect of OK-432 and PS-K seems to be based on activation of NK cells and prevention of MCMV-induced inhibition of the NK cell activity. PMID:6202880

Angiopoietin-1 protects the endothelial cells against advanced glycation end product injury by strengthening cell junctions and inhibiting cell apoptosis.

PubMed

Zhao, Jingling; Chen, Lei; Shu, Bin; Tang, Jinming; Zhang, Lijun; Xie, Julin; Liu, Xusheng; Xu, Yingbin; Qi, Shaohai

2015-08-01

Endothelial dysfunction is a major characteristic of diabetic vasculopathy. Protection of the vascular endothelium is an essential aspect of preventing and treating diabetic vascular complications. Although Angiopoietin-1 (Ang-1) is an important endothelial-specific protective factor, whether Ang-1 protects vascular cells undergoing advanced glycation end product (AGE) injury has not been investigated. The aim of the present study was to determine the potential effects of Ang-1 on endothelial cells after exposure to AGE. We show here that Ang-1 prevented AGE-induced vascular leakage by enhancing the adherens junctions between endothelial cells, and this process was mediated by the phosphorylation and membrane localization of VE-cadherin. Furthermore, Ang-1 also protected endothelial cells from AGE-induced death by regulating phosphatidylinositol 3-kinase (PI3K)/Akt-dependent Bad phosphorylation. Our findings suggest that the novel protective mechanisms of Ang-1 on endothelium are achieved by strengthening endothelial cell junctions and reducing endothelial cell death after AGE injury. © 2014 Wiley Periodicals, Inc.

Vitamin C and Vitamin E Protected B95-8 and Balb/c-3T3 Cells from Apoptosis Induced by Intermittent 50Hz ELF-EMF Radiation.

PubMed

Ding, Zhen; Li, Jintao; Li, Fan; Mephryar, Mohammadreza Mohammadzad; Wu, Shuicai; Zhang, Chen; Zeng, Yi

2017-01-01

The extremely low-frequency electromagnetic field (ELF-EMF), mainly emitted by electric transmission lines and household electronic appliances, is becoming a worldwide health risk. It is imperative to investigate the biological impacts of ELF-EMF and to identify products that are resistant to the radiation from 50 Hz ELF-EMF. In this study, we investigated the biological impacts of apoptosis caused by 50 Hz Power line ELF-EMF and the protective effects of Vit C and Vit E. We conducted this study in Beijing, China in 2013. B 95-8 and Balb/c-3T3 cells were divided into a sham group, an expo group and 3 expo groups in which the cells were preincubated with various concentrations of Vit C and Vit E. Then, all of the cells were exposed to 50 Hz Power line ELF-EMF and examined for apoptosis. The cells were collected for apoptosis detection after exposure. The percent of cells that undergoing apoptosis and preincubated with various concentrations of Vit C and Vit E were significantly lower than in the Expo group. Vit C and Vit E exert significant protective effects from 50 Hz ELF-EMF radiation. The optimal protective concentrations of Vit C and Vit E are 10 μmol/L and 25 μmol/L, respectively. The protective effect of vitamins was more apparent for Balb/c-3T3 cells than B 95-8 cells.

Formula Compatibility Identification of Dachengqi Decoction Based on the Effects of Absorbed Components in Cerulein-Injured Pancreatic AR42J Cells

PubMed Central

Zhang, Yumei; Zhu, Lin; Wang, Jia; Zhao, Jianlei; Zhao, Xianlin; Guo, Hui; Li, Juan; Tang, Wenfu

2016-01-01

Objective. To identify the herbal formula compatibility law based on the effects of the absorbed components from DCQD on the cerulein-injured AR42J cells. Methods. AR42J cells were pretreated for 30 min with or without the different concentrations of the absorbed components from DCQD individually or in combination or DCQD and coincubated with cerulein (10 nM) for a further 24 h. Cell viability, lactate dehydrogenase (LDH) release, and the levels of apoptosis and necrosis were measured. Results. Compared to DCQD, the individual or combination components partially protected cerulein-injured AR42J cells by increasing cell viability, reducing LDH release, and promoting apoptosis. Rhein, naringin, and honokiol were the main absorbed components from DCQD in cerulein-induced pancreatitis. Moreover, rhein in combination with naringin and honokiol had synergistic effects in protecting cerulein-injured AR42J cells and was better than the individual or the pairwise combination of the three components. Conclusions. The ten effective components from DCQD may elicit similar protective effects as DCQD on cerulein-induced pancreatitis. The principle of the formula compatibility of DCQD may be identified based on the effects of its absorbed components in cerulein-injured AR42J cells. PMID:27123032

Protective effects of total saponins from stem and leaf of Panax ginseng against cyclophosphamide-induced genotoxicity and apoptosis in mouse bone marrow cells and peripheral lymphocyte cells.

PubMed

Zhang, Qiu Hua; Wu, Chun Fu; Duan, Lian; Yang, Jing Yu

2008-01-01

Cyclophosphamide (CP), commonly used anti-cancer, induces oxidative stress and is cytotoxic to normal cells. It is very important to choice the protective agent combined CP to reduce the side effects in cancer treatment. Ginsenosides are biological active constituents of Panax ginseng C.A. Meyer that acts as the tonic agent for the cancer patients to reduce the side effects in the clinic application. Because CP is a pro-oxidant agent and induces oxidative stress by the generation of free radicals to decrease the activities of anti-oxidant enzymes, the protective effects of the total saponins from stem and leaf of P. ginseng C.A. Meyer (TSPG) act as an anti-oxidant agent against the decreased anti-oxidant enzymes, the genotoxicity and apoptosis induced by CP was carried out. The alkaline single cell gel electrophoresis was employed to detect DNA damage; flow cytometry assay and AO/EB staining assay were employed to measure cell apoptosis; the enzymatic anti-oxidants (T-SOD, CAT and GPx) and non-enzymatic anti-oxidant (GSH) were measured by the various colorimetric methods. CP induced the significant DNA damage in mouse peripheral lymphocytes in time- and dose-dependent manners, inhibited the activities of T-SOD, GPx and CAT, and decreased the contents of GSH in mouse blood, triggered bone marrow cell apoptosis at 6 and 12h. TSPG significantly reduced CP-induced DNA damages in bone marrow cells and peripheral lymphocyte cells, antagonized CP-induced reduction of T-SOD, GPx, CAT activities and the GSH contents, decreased the bone marrow cell apoptosis induced by CP. TSPG, significantly reduced the genotoxicity of CP in bone marrow cells and peripheral lymphocyte cells, and decreased the apoptotic cell number induced by CP in bone marrow cells. The effects of TSPG on T-SOD, GPx, CAT activities and GSH contents might partially contribute to its protective effects on CP-induced cell toxicities.

Corrosion resistant PEM fuel cell

DOEpatents

Li, Yang; Meng, Wen-Jin; Swathirajan, Swathy; Harris, Stephen Joel; Doll, Gary Lynn

2001-07-17

The present invention contemplates a PEM fuel cell having electrical contact elements (including bipolar plates/septums) comprising a titanium nitride coated light weight metal (e.g., Al or Ti) core, having a passivating, protective metal layer intermediate the core and the titanium nitride. The protective layer forms a barrier to further oxidation/corrosion when exposed to the fuel cell's operating environment. Stainless steels rich in CR, Ni, and Mo are particularly effective protective interlayers.

Corrosion resistant PEM fuel cell

DOEpatents

Li, Yang; Meng, Wen-Jin; Swathirajan, Swathy; Harris, Stephen Joel; Doll, Gary Lynn

2002-01-01

The present invention contemplates a PEM fuel cell having electrical contact elements (including bipolar plates/septums) comprising a titanium nitride coated light weight metal (e.g., Al or Ti) core, having a passivating, protective metal layer intermediate the core and the titanium nitride. The protective layer forms a barrier to further oxidation/corrosion when exposed to the fuel cell's operating environment. Stainless steels rich in CR, Ni, and Mo are particularly effective protective interlayers.

Corrosion resistant PEM fuel cell

DOEpatents

Li, Yang; Meng, Wen-Jin; Swathirajan, Swathy; Harris, Stephen J.; Doll, Gary L.

1997-01-01

The present invention contemplates a PEM fuel cell having electrical contact elements (including bipolar plates/septums) comprising a titanium nitride coated light weight metal (e.g., Al or Ti) core, having a passivating, protective metal layer intermediate the core and the titanium nitride. The protective layer forms a barrier to further oxidation/corrosion when exposed to the fuel cell's operating environment. Stainless steels rich in CR, Ni, and Mo are particularly effective protective interlayers.

Engineered Mesenchymal Cells Improve Passive Immune Protection Against Lethal Venezuelan Equine Encephalitis Virus Exposure

PubMed Central

Braid, Lorena R.; Davies, John E.; Nagata, Les P.

2016-01-01

Mesenchymal stromal cells (MSCs) are being exploited as gene delivery vectors for various disease and injury therapies. We provide proof-of-concept that engineered MSCs can provide a useful, effective platform for protection against infectious disease. Venezuelan equine encephalitis virus (VEEV) is a mosquito-borne pathogen affecting humans and equines and can be used in bio-warfare. No licensed vaccine or antiviral agent currently exists to combat VEEV infection in humans. Direct antibody administration (passive immunity) is an effective, but short-lived, method of providing immediate protection against a pathogen. We compared the protective efficacy of human umbilical cord perivascular cells (HUCPVCs; a rich source of MSCs), engineered with a transgene encoding a humanized VEEV-neutralizing antibody (anti-VEEV), to the purified antibody. In athymic mice, the anti-VEEV antibody had a half-life of 3.7 days, limiting protection to 2 or 3 days after administration. In contrast, engineered HUCPVCs generated protective anti-VEEV serum titers for 21–38 days after a single intramuscular injection. At 109 days after transplantation, 10% of the mice still had circulating anti-VEEV antibody. The mice were protected against exposure to a lethal dose of VEEV by an intramuscular pretreatment injection with engineered HUCPVCs 24 hours or 10 days before exposure, demonstrating both rapid and prolonged immune protection. The present study is the first to describe engineered MSCs as gene delivery vehicles for passive immunity and supports their utility as antibody delivery vehicles for improved, single-dose prophylaxis against endemic and intentionally disseminated pathogens. Significance Direct injection of monoclonal antibodies (mAbs) is an important strategy to immediately protect the recipient from a pathogen. This strategy is critical during natural outbreaks or after the intentional release of bio-weapons. Vaccines require weeks to become effective, which is not practical for first responders immediately deployed to an infected region. However, mAb recipients often require booster shots to maintain protection, which is expensive and impractical once the first responders have been deployed. The present study has shown, for the first time, that mesenchymal stromal cells are effective gene delivery vehicles that can significantly improve mAb-mediated immune protection in a single, intramuscular dose of engineered cells. Such a cell-based delivery system can provide extended life-saving protection in the event of exposure to biological threats using a more practical, single-dose regimen. PMID:27334491

Lycopene as A Carotenoid Provides Radioprotectant and Antioxidant Effects by Quenching Radiation-Induced Free Radical Singlet Oxygen: An Overview

PubMed Central

Pirayesh Islamian, Jalil; Mehrali, Habib

2015-01-01

Radio-protectors are agents that protect human cells and tissues from undesirable effects of ionizing radiation by mainly scavenging radiation-induced free radicals. Although chemical radio-protectors diminish these deleterious side effects they induce a number of unwanted effects on humans such as blood pressure modifications, vomiting, nausea, and both local and generalized cutaneous reactions. These disadvantages have led to emphasis on the use of some botanical radio-protectants as alternatives. This review has collected and organized studies on a plant-derived radio-protector, lycopene. Lycopene protects normal tissues and cells by scavenging free radicals. Therefore, treatment of cells with lycopene prior to exposure to an oxidative stress, oxidative molecules or ionizing radiation may be an effective approach in diminishing undesirable effects of radiation byproducts. Studies have designated lycopene to be an effective radio-protector with negligible side effects. PMID:25685729

Inflammatory Effects of the Plant Protection Product Stifenia (FEN560) on Vertebrates.

PubMed

Teyssier, Lény; Colussi, Julie; Delemasure, Stéphanie; Chluba, Johanna; Wendehenne, David; Lamotte, Olivier; Connat, Jean-Louis

2017-01-01

Plant defense stimulators (PDSs) rely on the activation of plant innate immunity in order to protect crops against various pests. These molecules are thought to be a safer alternative to classical plant protection products. Given that innate immune systems share common features in plants and vertebrates, PDS can potentially cross-react with innate immunity of non-target organisms. To test this hypothesis, we studied effects of the commercial PDS Stifenia (FEN560), which is composed of crushed fenugreek seeds. We tested various concentrations of Stifenia (0.03-1 mg mL -1 ) on human peripheral blood mononuclear cells and checked, 20 h later, cell metabolic activity (MA) using XTT assay, cell death by flow cytometry analysis, and IL-1β inflammatory cytokine released in the culture medium using ELISA. Stifenia induced a general decrease of the cell MA, which was concomitant with a dose-dependent release of IL-1β. Our results highlight the activation of human immune cells. The inflammatory effect of Stifenia was partially inhibited by pan-caspase inhibitor. Accordingly, Stifenia induced the release of p20 caspase-1 fragment into the culture medium suggesting the involvement of the NLRP3 inflammasome. Furthermore, we observed that Stifenia can induce cell death. We also tested the effect of Stifenia on Zebrafish larvae. After 24 h of exposure, Stifenia induced a dose-dependent IL-1β and TNFα gene expression. The human-cell-based approach developed in this work revealed a high sensitivity concerning inflammatory properties of a plant protection product. These tests could be routinely used to screen the potential adverse effects of this type of compounds. Finally, our results suggest a potential danger of using extensively certain PDS for crop protection.

Inflammatory Effects of the Plant Protection Product Stifenia (FEN560) on Vertebrates

PubMed Central

Teyssier, Lény; Colussi, Julie; Delemasure, Stéphanie; Chluba, Johanna; Wendehenne, David; Lamotte, Olivier; Connat, Jean-Louis

2017-01-01

Plant defense stimulators (PDSs) rely on the activation of plant innate immunity in order to protect crops against various pests. These molecules are thought to be a safer alternative to classical plant protection products. Given that innate immune systems share common features in plants and vertebrates, PDS can potentially cross-react with innate immunity of non-target organisms. To test this hypothesis, we studied effects of the commercial PDS Stifenia (FEN560), which is composed of crushed fenugreek seeds. We tested various concentrations of Stifenia (0.03–1 mg mL−1) on human peripheral blood mononuclear cells and checked, 20 h later, cell metabolic activity (MA) using XTT assay, cell death by flow cytometry analysis, and IL-1β inflammatory cytokine released in the culture medium using ELISA. Stifenia induced a general decrease of the cell MA, which was concomitant with a dose-dependent release of IL-1β. Our results highlight the activation of human immune cells. The inflammatory effect of Stifenia was partially inhibited by pan-caspase inhibitor. Accordingly, Stifenia induced the release of p20 caspase-1 fragment into the culture medium suggesting the involvement of the NLRP3 inflammasome. Furthermore, we observed that Stifenia can induce cell death. We also tested the effect of Stifenia on Zebrafish larvae. After 24 h of exposure, Stifenia induced a dose-dependent IL-1β and TNFα gene expression. The human-cell-based approach developed in this work revealed a high sensitivity concerning inflammatory properties of a plant protection product. These tests could be routinely used to screen the potential adverse effects of this type of compounds. Finally, our results suggest a potential danger of using extensively certain PDS for crop protection. PMID:28484691

The protective effects of resveratrol on Schwann cells with toxicity induced by ethanol in vitro.

PubMed

Yuan, Hongtu; Zhang, Jingfen; Liu, Huaxiang; Li, Zhenzhong

2013-09-01

Schwann cells (SCs) are the myelin forming cells in the peripheral nervous system, they play a key role in the pathology of various polyneuropathies and provide trophic support to axons via expression of various neurotrophic factors, such as nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF). Ethanol (EtOH) adversely affected both SCs proliferation and myelin formation in culture. Resveratrol (Res) has been shown to regulate many cellular processes and to display multiple protective and therapeutic effects. Whether Res has protective effects on SCs with EtOH-induced toxicity is still unclear. The protective efficacy of Res on EtOH-treated SCs in vitro was investigated in the present study. Res improved cell viability of the EtOH-treated SCs. Hoechst 33342 staining and terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate nick-end labeling analysis showed that the EtOH-induced apoptosis was inhibited by Res. The effects of Res were blocked by the 5'-adenosine monophosphate-activated protein kinase inhibitor Compound C and the silencing information regulator T1 inhibitor nicotinamide. Res could increase the mRNA and protein levels of BDNF and GDNF in the EtOH-treated SCs. However, the EtOH-induced increase of NGF in the SCs is inhibited by Res. The data from the present study indicate that Res protects SCs from EtOH-induced cell death and regulates the expression of neurotrophicfactors. Res and its derivative may be effective for the treatment of neuropathic diseases induced by EtOH. Copyright © 2013 Elsevier Ltd. All rights reserved.

Mitochondria-Targeted Vitamin E Protects Skin from UVB-Irradiation.

PubMed

Kim, Won-Serk; Kim, Ikyon; Kim, Wang-Kyun; Choi, Ju-Yeon; Kim, Doo Yeong; Moon, Sung-Guk; Min, Hyung-Keun; Song, Min-Kyu; Sung, Jong-Hyuk

2016-05-01

Mitochondria-targeted vitamin E (MVE) is designed to accumulate within mitochondria and is applied to decrease mitochondrial oxidative damage. However, the protective effects of MVE in skin cells have not been identified. We investigated the protective effect of MVE against UVB in dermal fibroblasts and immortalized human keratinocyte cell line (HaCaT). In addition, we studied the wound-healing effect of MVE in animal models. We found that MVE increased the proliferation and survival of fibroblasts at low concentration (i.e., nM ranges). In addition, MVE increased collagen production and downregulated matrix metalloproteinase1. MVE also increased the proliferation and survival of HaCaT cells. UVB increased reactive oxygen species (ROS) production in fibroblasts and HaCaT cells, while MVE decreased ROS production at low concentration. In an animal experiment, MVE accelerated wound healing from laser-induced skin damage. These results collectively suggest that low dose MVE protects skin from UVB irradiation. Therefore, MVE can be developed as a cosmetic raw material.

Redox properties of ginger extracts: Perspectives of use of Zingiber officinale Rosc. as antidiabetic agent

PubMed Central

Cupáková, Máriá; Ťažký, Anton; Mičová, Júlia; Kolek, Emil; Košt'álová, Daniela

2013-01-01

In traditional medicine, several medicinal plants or their extracts have been used to treat diabetes. Zingiber officinale Roscoe, known commonly as ginger, is consumed worldwide in cookeries as a spice and flavouring agent. It has been used as the spice and medicine for thousands of years. The present study was undertaken to investigate the potential protective effect of Zingiber officinale Rosc. in a model of oxidative damage to pancreatic β cells. The free radical scavenging activities and composition of the isolated n-hexane and ethanolic extracts were confronted with their protective, antioxidant and cytotoxic effects in INS-1E β cells. Unlike the n-hexane extract (exerting, paradoxically, stronger antiradical capacity), both low cytotoxicity and remarkable protective effects on β cell viability, followed by lowering oxidative stress markers were found for the ethanolic extract Zingiber officinale Rosc. The present study is the first pilot study to assess the protective potential of Zingiber officinale Rosc. in a model of cytotoxic conditions imposed by diabetes in β cells. PMID:24170976

Redox properties of ginger extracts: Perspectives of use of Zingiber officinale Rosc. as antidiabetic agent.

PubMed

Račková, Lucia; Cupáková, Máriá; Tažký, Anton; Mičová, Júlia; Kolek, Emil; Košt'álová, Daniela

2013-03-01

In traditional medicine, several medicinal plants or their extracts have been used to treat diabetes. Zingiber officinale Roscoe, known commonly as ginger, is consumed worldwide in cookeries as a spice and flavouring agent. It has been used as the spice and medicine for thousands of years. The present study was undertaken to investigate the potential protective effect of Zingiber officinale Rosc. in a model of oxidative damage to pancreatic β cells. The free radical scavenging activities and composition of the isolated n-hexane and ethanolic extracts were confronted with their protective, antioxidant and cytotoxic effects in INS-1E β cells. Unlike the n-hexane extract (exerting, paradoxically, stronger antiradical capacity), both low cytotoxicity and remarkable protective effects on β cell viability, followed by lowering oxidative stress markers were found for the ethanolic extract Zingiber officinale Rosc. The present study is the first pilot study to assess the protective potential of Zingiber officinale Rosc. in a model of cytotoxic conditions imposed by diabetes in β cells.

Pyridostigmine bromide protection against acetylcholinesterase inhibition by pesticides.

PubMed

Henderson, John D; Glucksman, Gabriela; Leong, Bryan; Tigyi, Andras; Ankirskaia, Anna; Siddique, Imteaz; Lam, Helen; DePeters, Ed; Wilson, Barry W

2012-01-01

Pyridostigmine bromide (PB) has been used to protect soldiers from the toxic effects of soman, a chemical warfare agent. Recent research shows that pyridostigmine bromide protects a significant percentage of acetylcholinesterase in isolated human intercostal muscle. Findings presented here indicate that red blood cell acetylcholinesterase is similarly protected by pyridostigmine bromide from the action of diisopropyl fluorophosphate and several organophosphate pesticides including chlorpyrifos-oxon, diazinon-oxon, and paraoxon, but not malaoxon, using the bovine red blood cell as a subject. These findings suggest that pretreatment with PB may protect growers, farmworkers, first responders, and the public, in general, from the effects of selected pesticides. Copyright © 2011 Wiley Periodicals, Inc.

The IL23R R381Q Gene Variant Protects against Immune-Mediated Diseases by Impairing IL-23-Induced Th17 Effector Response in Humans

PubMed Central

Di Meglio, Paola; Di Cesare, Antonella; Laggner, Ute; Chu, Chung-Ching; Napolitano, Luca; Villanova, Federica; Tosi, Isabella; Capon, Francesca; Trembath, Richard C.; Peris, Ketty; Nestle, Frank O.

2011-01-01

IL-23 and Th17 cells are key players in tissue immunosurveillance and are implicated in human immune-mediated diseases. Genome-wide association studies have shown that the IL23R R381Q gene variant protects against psoriasis, Crohn's disease and ankylosing spondylitis. We investigated the immunological consequences of the protective IL23R R381Q gene variant in healthy donors. The IL23R R381Q gene variant had no major effect on Th17 cell differentiation as the frequency of circulating Th17 cells was similar in carriers of the IL23R protective (A) and common (G) allele. Accordingly, Th17 cells generated from A and G donors produced similar amounts of Th17 cytokines. However, IL-23-mediated Th17 cell effector function was impaired, as Th17 cells from A allele carriers had significantly reduced IL-23-induced IL-17A production and STAT3 phosphorylation compared to G allele carriers. Our functional analysis of a human disease-associated gene variant demonstrates that IL23R R381Q exerts its protective effects through selective attenuation of IL-23-induced Th17 cell effector function without interfering with Th17 differentiation, and highlights its importance in the protection against IL-23-induced tissue pathologies. PMID:21364948

The IL23R R381Q gene variant protects against immune-mediated diseases by impairing IL-23-induced Th17 effector response in humans.

PubMed

Di Meglio, Paola; Di Cesare, Antonella; Laggner, Ute; Chu, Chung-Ching; Napolitano, Luca; Villanova, Federica; Tosi, Isabella; Capon, Francesca; Trembath, Richard C; Peris, Ketty; Nestle, Frank O

2011-02-22

IL-23 and Th17 cells are key players in tissue immunosurveillance and are implicated in human immune-mediated diseases. Genome-wide association studies have shown that the IL23R R381Q gene variant protects against psoriasis, Crohn's disease and ankylosing spondylitis. We investigated the immunological consequences of the protective IL23R R381Q gene variant in healthy donors. The IL23R R381Q gene variant had no major effect on Th17 cell differentiation as the frequency of circulating Th17 cells was similar in carriers of the IL23R protective (A) and common (G) allele. Accordingly, Th17 cells generated from A and G donors produced similar amounts of Th17 cytokines. However, IL-23-mediated Th17 cell effector function was impaired, as Th17 cells from A allele carriers had significantly reduced IL-23-induced IL-17A production and STAT3 phosphorylation compared to G allele carriers. Our functional analysis of a human disease-associated gene variant demonstrates that IL23R R381Q exerts its protective effects through selective attenuation of IL-23-induced Th17 cell effector function without interfering with Th17 differentiation, and highlights its importance in the protection against IL-23-induced tissue pathologies.

The 17D-204 Vaccine Strain-Induced Protection against Virulent Yellow Fever Virus Is Mediated by Humoral Immunity and CD4+ but not CD8+ T Cells.

PubMed

Watson, Alan M; Lam, L K Metthew; Klimstra, William B; Ryman, Kate D

2016-07-01

A gold standard of antiviral vaccination has been the safe and effective live-attenuated 17D-based yellow fever virus (YFV) vaccines. Among more than 500 million vaccinees, only a handful of cases have been reported in which vaccinees developed a virulent wild type YFV infection. This efficacy is presumed to be the result of both neutralizing antibodies and a robust T cell response. However, the particular immune components required for protection against YFV have never been evaluated. An understanding of the immune mechanisms that underlie 17D-based vaccine efficacy is critical to the development of next-generation vaccines against flaviviruses and other pathogens. Here we have addressed this question for the first time using a murine model of disease. Similar to humans, vaccination elicited long-term protection against challenge, characterized by high neutralizing antibody titers and a robust T cell response that formed long-lived memory. Both CD4+ and CD8+ T cells were polyfunctional and cytolytic. Adoptive transfer of immune sera or CD4+ T cells provided partial protection against YFV, but complete protection was achieved by transfer of both immune sera and CD4+ T cells. Thus, robust CD4+ T cell activity may be a critical contributor to protective immunity elicited by highly effective live attenuated vaccines.

The 17D-204 Vaccine Strain-Induced Protection against Virulent Yellow Fever Virus Is Mediated by Humoral Immunity and CD4+ but not CD8+ T Cells

PubMed Central

Lam, L. K. Metthew; Klimstra, William B.

2016-01-01

A gold standard of antiviral vaccination has been the safe and effective live-attenuated 17D-based yellow fever virus (YFV) vaccines. Among more than 500 million vaccinees, only a handful of cases have been reported in which vaccinees developed a virulent wild type YFV infection. This efficacy is presumed to be the result of both neutralizing antibodies and a robust T cell response. However, the particular immune components required for protection against YFV have never been evaluated. An understanding of the immune mechanisms that underlie 17D-based vaccine efficacy is critical to the development of next-generation vaccines against flaviviruses and other pathogens. Here we have addressed this question for the first time using a murine model of disease. Similar to humans, vaccination elicited long-term protection against challenge, characterized by high neutralizing antibody titers and a robust T cell response that formed long-lived memory. Both CD4+ and CD8+ T cells were polyfunctional and cytolytic. Adoptive transfer of immune sera or CD4+ T cells provided partial protection against YFV, but complete protection was achieved by transfer of both immune sera and CD4+ T cells. Thus, robust CD4+ T cell activity may be a critical contributor to protective immunity elicited by highly effective live attenuated vaccines. PMID:27463517

Acorus tatarinowii Schott extract protects PC12 cells from amyloid-beta induced neurotoxicity.

PubMed

An, Hong-Mei; Li, Guo-Wen; Lin, Chen; Gu, Chao; Jin, Miao; Sun, Wen-Xian; Qiu, Ming-Feng; Hu, Bing

2014-05-01

Amyloid-beta induced neurotoxicity has been identified as a major cause of Alzheimer's disease. Acorus tatarinowii Schott is one of the most frequently used Chinese herbs for Alzheimer's disease treatment. However, the effects of Acorus tatarinowii Schott on amyloid-beta mediated nerve cell damage remains unknown. In the present study, neuronal differentiated PC12 cells were used as a model to evaluate the effects of A. tatarinowii Schott extract (ATSE) against Abeta25-35 induced neurotoxicity. The results showed pretreatment with ATSE significantly protected PC12 cells from Abeta25-35 induced cell death, lactate dehydrogenase release, DNA damage, mitochondrial dysfunction and cytochrome c release from mitochondria. In addition, pretreatment with ATSE also significantly inhibited Abeta25-35 induced caspase-3 activation and reactive oxygen species generation in PC12 cells. These observations suggested that ATSE protects PC12 cells from amyloid-beta induced neurotoxicity.

Protective effect of ursolic acid from Cornus officinalis on the hydrogen peroxide-induced damage of HEI-OC1 auditory cells.

PubMed

Yu, Hyeon-Hee; Hur, Jong-Moon; Seo, Se-Jeong; Moon, Hae-Dalma; Kim, Hyun-Jin; Park, Rae-Kil; You, Yong-Ouk

2009-01-01

The fruits of Cornus officinalis have been used in traditional oriental medicine for treatment of inner ear diseases, such as tinnitus and hearing loss. In the present study, we investigated the protective effect of C. officinalis on hydrogen peroxide-induced cytotoxicity in HEI-OC1 auditory cells. The results from bioassay-guided fractionation of methanol extract of C. officinalis fruits showed that ursolic acid is a major active component. Ursolic acid (0.05-2 microg/ml) had protective effect against the HEI-OC1 cell damage and reduced lipid peroxidation in a dose-dependent manner. In addition, pre-treatment with ursolic acid significantly attenuated the decrease of activities of catalase (CAT) and glutathione peroxidase (GPX), but superoxide dismutase (SOD) activity was not significantly affected by ursolic acid. These results indicate that ursolic acid protects hydrogen peroxide-induced HEI-OC1 cell damage through inhibition of lipid peroxidation and induction of antioxidant enzymes, CAT and GPX, and may be one of the active components responsible for these effects of C. officinalis fruits.

Artesunate protects pancreatic beta cells against cytokine-induced damage via SIRT1 inhibiting NF-κB activation.

PubMed

Yu, L; Chen, J F; Shuai, X; Xu, Y; Ding, Y; Zhang, J; Yang, W; Liang, X; Su, D; Yan, C

2016-01-01

Artesunate (ART) has been known as the most effective and safe reagents to treat malaria for many years. In this study, we explored whether ART could protect pancreatic beta-cell against cytokine-induced damage. The production of nitrite (NO) was detected with the Griess Assay Kit. SIRT1 and inducible nitric oxide synthase (iNOS) expression were determined with Western blot. The transcriptional activity of NF-κB was evaluated by luciferase reporter assay. The expression of Sirt1 was silenced by RNA interference. Glucose-stimulated insulin secretion (GSIS) and potassium-stimulated insulin secretion (KSIS) assays were performed to measure the effect of ART on pancreatic beta-cells' function. The effect of ART on beta-cells apoptosis was evaluated by using Hochest/PI staining and TUNEL assay. ART enhanced GSIS (KSIS) and reduced apoptosis of pancreatic beta-cells induced by IL-1β. Further study showed that ART inhibited IL-1β-induced increase of NF-κB activity, iNOS expression, and NO production. Moreover, ART up-regulated SIRT1 expression in INS-1 cells and islets exposed to IL-1β. Inhibition of SIRT1 expression could partially abolished the inhibitory effect of ART on NF-κB activity in IL-1β-treated beta-cells. More importantly, the protective effect of ART on cytokine-induced damage was reversed by silencing SIRT1 expression. ART can elicit a protective effect on beta-cells exposed to IL-1β by stimulating SIRT1 expression, which resulted in the decrease of NF-κB activity, iNOS expression, and NO production. Hence, ART might be an effective drug for diabetes.

Chlorella protects against hydrogen peroxide-induced pancreatic β-cell damage.

PubMed

Lin, Chia-Yu; Huang, Pei-Jane; Chao, Che-Yi

2014-12-01

Oxidative stress has been implicated in the etiology of pancreatic β-cell dysfunction and diabetes. Studies have shown that chlorella could be important in health promotion or disease prevention through its antioxidant capacity. However, whether chlorella has a cytoprotective effect in pancreatic β-cells remains to be elucidated. We investigated the protective effects of chlorella on H2O2-induced oxidative damage in INS-1 (832/13) cells. Chlorella partially restored cell viability after H2O2 toxicity. To further investigate the effects of chlorella on mitochondria function and cellular oxidative stress, we analyzed mitochondria membrane potential, ATP concentrations, and cellular levels of reactive oxygen species (ROS). Chlorella prevented mitochondria disruption and maintained cellular ATP levels after H2O2 toxicity. It also normalized intracellular levels of ROS to that of control in the presence of H2O2. Chlorella protected cells from apoptosis as indicated by less p-Histone and caspase 3 activation. In addition, chlorella not only enhanced glucose-stimulated insulin secretion (GSIS), but also partially restored the reduced GSIS after H2O2 toxicity. Our results suggest that chlorella is effective in amelioration of cellular oxidative stress and destruction, and therefore protects INS-1 (832/13) cells from H2O2-induced apoptosis and increases insulin secretion. Chlorella should be studied for use in the prevention or treatment of diabetes.

Nitric oxide protects the mitochondria of anterior pituitary cells and prevents cadmium-induced cell death by reducing oxidative stress.

PubMed

Poliandri, Ariel H B; Machiavelli, Leticia I; Quinteros, Alnilan F; Cabilla, Jimena P; Duvilanski, Beatriz H

2006-02-15

Cadmium (Cd2+) is a highly toxic metal that affects the endocrine system. We have previously shown that Cd2+ induces caspase-3 activation and apoptosis of anterior pituitary cells and that endogenous nitric oxide (NO) protects these cells from Cd2+. Here we investigate the mechanisms by which NO exerts this protective role. Cd2+ (25 microM) reduced the mitochondrial membrane potential (MMP) as measured by flow cytometry. Cd2+-induced apoptosis was mitochondrial dependent since cyclosporin A protected the cells from this metal. Inhibition of NO synthesis with 0.5 mM L-NAME increased the effect of Cd2+ on MMP, whereas the NO donor DETANONOate (0.1 mM) reduced it. Cd2+ increased the production of reactive oxygen species (ROS) as measured by flow cytometry. This effect was electron-transfer-chain-dependent since it was inhibited by rotenone. In fact, rotenone reduced the cytotoxic effect of the metal. The action of Cd2+ on mitochondrial integrity was ROS dependent. Trolox, an antioxidant, inhibited the effect of the metal on the MMP. Cd2+-induced increase in ROS generation was reduced by DETANONOate. There are discrepancies concerning the role of NO in Cd2+ toxicity. Here we show that NO reduces Cd2+ toxicity by protecting the mitochondria from oxidative stress in a system where NO plays a regulatory role.

The Impact of Exercise on the Vulnerability of Dopamine Neurons to Cell Death in Animal Models of Parkinson’s Disease

DTIC Science & Technology

2005-07-01

of the proteasome inhibitor, MG132, and that methamphetamine protected against 6-OHDA. We are now exploring the mechanism of this effect. 7...how much exercise is required, when must it occur, and how permanent are the effects; (3) if exercise also protects against the increased...toxin (Leak et al., 2004). This may be a general phenomenon, as we have also shown in the same cell line that 6-OHDA protected against the toxic effects

Protective effect of cannabidiol on hydrogen peroxide‑induced apoptosis, inflammation and oxidative stress in nucleus pulposus cells.

PubMed

Chen, Jie; Hou, Chen; Chen, Xin; Wang, Dong; Yang, Pinglin; He, Xijing; Zhou, Jinsong; Li, Haopeng

2016-09-01

Cannabidiol, a major component of marijuana, protects nerves, and exerts antispasmodic, anti-inflammatory and anti‑anxiety effects. In the current study, the protective effect of cannabidiol was observed to prevent hydrogen peroxide (H2O2)‑induced apoptosis, inflammation and oxidative stress in nucleus pulposus cells. Nucleus pulposus cells were isolated from rats and cultured in vitro, and H2O2 was used to construct the nucleus pulposus cell model. Cell viability of the nucleus pulposus cells was assessed using a 3‑(4,5-dimethylthiazol-2-yl)-2,5‑diphenyltetrazolium bromide assay. The ratio of apoptotic cells, and caspase‑3 or cyclooxygenase‑2 (COX‑2) mRNA expression was analyzed by annexin V‑fluorescein isothiocyanate/propidium‑iodide staining and reverse transcription‑quantitative polymerase chain reaction, respectively. The quantities of interleukin (IL)‑1β and interleukin‑6 were measured using a series of assay kits. B-cell lymphoma 2 (Bcl‑2) and inducible nitric oxide synthase (iNOS) protein expression levels were analyzed using western blotting. The present study identified that cannabidiol enhanced cell viability and reduced apoptosis in H2O2‑treated nucleus pulposus cells in vitro using a lumbar disc herniation (LDH) model. In addition, cannabidiol reduced caspase‑3 gene expression and augmented the Bcl‑2 protein expression levels in the nucleus pulposus cells following H2O2 exposure. Pre‑treatment with cannabidiol suppressed the promotion of COX‑2, iNOS, IL‑1β and IL‑6 expression in the nucleus pulposus cells following H2O2 exposure. Taken together, these results suggest that cannabidiol potentially exerts its protective effect on LDH via the suppression of anti‑apoptosis, anti‑inflammation and anti‑oxidative activities in nucleus pulposus cells.

Clozapine protects PC-12 cells from death due to oxidative stress induced by hydrogen peroxide via a cell-type specific mechanism involving inhibition of extracellular signal-regulated kinase phosphorylation.

PubMed

Magliaro, Brian C; Saldanha, Colin J

2009-08-04

Recent evidence suggests that some atypical antipsychotic drugs may protect against oxidative stress and consequent neurodegeneration by mechanisms that remain unclear. Using the neuron-like rat pheochromocytoma (PC-12) cell line, Clozapine and N-desmethylclozapine were tested for their ability to protect against cell death due to oxidative stress induced by hydrogen peroxide (H(2)O(2)). These drugs demonstrated significant protection of PC-12 cells, as measured by both the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrasodium bromide (MTT) and Alamar Blue cell viability assays. However, neither viability assay detected a protective effect of Clozapine on human embryonic kidney (HEK293), rat primary cortical neurons, or human neuroblastoma (SH-SY5Y) exposed to H(2)O(2) treatment. The mechanism of protection involves a PC-12 cell-specific differential response to H(2)O(2) treatment vs. the other cell lines. Pre-treatment with 250 microM or 125 microM diethyldithiocarbamate (DETC), a superoxide dismutase (SOD) inhibitor, unexpectedly showed protection of the PC-12 cells from H(2)O(2) treatment. Western blots revealed that Clozapine, N-desmethylclozapine, and DETC reduce the phosphorylation of extracellular signal-regulated kinase (ERK) that is caused by H(2)O(2) exposure in PC-12 cells. In both HEK293 and SH-SY5Y cells, H(2)O(2) exposure did not increase ERK phosphorylation over control, demonstrating a different response to H(2)O(2) vs. PC-12 cells, and explaining why Clozapine could not protect these cells. Also, U0126, a specific MEK inhibitor, was able to protect PC-12 cells from H(2)O(2) exposure, showing that inhibiting ERK phosphorylation is sufficient to provide protection. Cumulatively, these results indicate that Clozapine, N-desmethylclozapine, DETC, and U0126 protect PC-12 cells by blocking the cell-type specific H(2)O(2) induced increase in ERK phosphorylation.

Agmatine effects on mitochondrial membrane potential and NF-κB activation protect against rotenone-induced cell damage in human neuronal-like SH-SY5Y cells.

PubMed

Condello, Salvatore; Currò, Monica; Ferlazzo, Nadia; Caccamo, Daniela; Satriano, Joseph; Ientile, Riccardo

2011-01-01

Agmatine, an endogenous arginine metabolite, has been proposed as a novel neuromodulator that plays protective roles in the CNS in several models of cellular damage. However, the mechanisms involved in these protective effects in neurodegenerative diseases are poorly understood. The present study was undertaken to investigate the effects of agmatine on cell injury induced by rotenone, commonly used in establishing in vivo and in vitro models of Parkinson's disease, in human-derived dopaminergic neuroblastoma cell line (SH-SY5Y). We report that agmatine dose-dependently suppressed rotenone-induced cellular injury through a reduction of oxidative stress. Similar effects were obtained by spermine, suggesting a scavenging effect for these compounds. However, unlike spermine, agmatine also prevented rotenone-induced nuclear factor-κB nuclear translocation and mitochondrial membrane potential dissipation. Furthermore, rotenone-induced increase in apoptotic markers, such as caspase 3 activity, Bax expression and cytochrome c release, was significantly attenuated with agmatine treatment. These findings demonstrate mitochondrial preservation with agmatine in a rotenone model of apoptotic cell death, and that the neuroprotective action of agmatine appears because of suppressing apoptotic signalling mechanisms. Thus, agmatine may have therapeutic potential in the treatment of Parkinson's disease by protecting dopaminergic neurons.

Roles of CD4+ T Cells and Gamma Interferon in Protective Immunity against Babesia microti Infection in Mice

PubMed Central

Igarashi, Ikuo; Suzuki, Reiko; Waki, Seiji; Tagawa, Yoh-Ichi; Seng, Seyha; Tum, Sothyra; Omata, Yoshitaka; Saito, Atsushi; Nagasawa, Hideyuki; Iwakura, Yohichiro; Suzuki, Naoyoshi; Mikami, Takeshi; Toyoda, Yutaka

1999-01-01

Babesia microti produces a self-limiting infection in mice, and recovered mice are resistant to reinfection. In the present study, the role of T cells in protective immunity against challenge infection was examined. BALB/c mice which recovered from primary infection showed strong protective immunity against challenge infection. In contrast, nude mice which failed to control the primary infection and were cured with an antibabesial drug did not show protection against challenge infection. Treatment of immune mice with anti-CD4 monoclonal antibody (MAb) diminished the protective immunity against challenge infection, but treatment with anti-CD8 MAb had no effect on the protection. Transfer of CD4+ T-cell-depleted spleen cells resulted in higher parasitemia than transfer of CD8+ T-cell-depleted spleen cells. A high level of gamma interferon (IFN-γ), which was produced by CD4+ T cells, was observed for the culture supernatant of spleen cells from immune mice, and treatment of immune mice with anti-IFN-γ MAb partially reduced the protection. Moreover, no protection against challenge infection was found in IFN-γ-deficient mice. On the other hand, treatment of immune mice with MAbs against interleukin-2 (IL-2), IL-4, or tumor necrosis factor alpha did not affect protective immunity. These results suggest essential requirements for CD4+ T cells and IFN-γ in protective immunity against challenge infection with B. microti. PMID:10417185

Protective effects of fucoxanthin against ferric nitrilotriacetate-induced oxidative stress in murine hepatic BNL CL.2 cells.

PubMed

Liu, Cheng-Ling; Liang, Ai-Ling; Hu, Miao-Lin

2011-10-01

Fucoxanthin is a carotenoid that is rich in some seaweed. Although fucoxanthin has been reported to possess radical-scavenging activities in vitro, little is known whether it may protect against iron-induced oxidative stress in cultured cells. In this study, we examined the protection of fucoxanthin against oxidative damage in BNL CL.2 cells induced by ferric nitrilotriacetate (Fe-NTA). The data show that incubation of BNL CL.2 cells with Fe-NTA for 30 min significantly decreased cell proliferation, whereas pretreatment with fucoxanthin (1-20 μΜ) for 24h significantly recovered cell proliferation in a dose-dependent manner. In addition, fucoxanthin pretreatment significantly decreased intracellular reactive oxygen species (ROS) and DNA damage in BNL CL.2 cells incubated with Fe-NTA for 30 min. Moreover, fucoxanthin markedly decreased the level of thiobarbituric acid-reactive substances (TBARS) and protein carbonyl contents in BNL CL.2 cells induced by Fe-NTA. By contrast, fucoxanthin significantly increased the levels of GSH in a concentration-dependent manner. These results demonstrate that fucoxanthin at 1-20μΜ effectively prevents cytotoxicity in BNL CL.2 cells treated with Fe-NTA, and that the protective effect is likely associated with decreased intracellular ROS, TBARS, protein carbonyl contents and increased GSH levels. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

Poly(Lactide-Co-Glycolide)-Monomethoxy-Poly-(Polyethylene Glycol) Nanoparticles Loaded with Melatonin Protect Adipose-Derived Stem Cells Transplanted in Infarcted Heart Tissue.

PubMed

Ma, Qiang; Yang, Junjie; Huang, Xu; Guo, Weisheng; Li, Sulei; Zhou, Hao; Li, Jingwei; Cao, Feng; Chen, Yundai

2018-04-01

Stem cell transplantation is a promising therapeutic strategy for myocardial infarction. However, transplanted cells face low survival rates due to oxidative stress and the inflammatory microenvironment in ischemic heart tissue. Melatonin has been used as a powerful endogenous antioxidant to protect cells from oxidative injury. However, melatonin cannot play a long-lasting effect against the hostile microenvironment. Nano drug delivery carriers have the ability to protect the loaded drug from degradation in physiological environments in a controlled manner, which results in longer effects and decreased side effects. Therefore, we constructed poly(lactide-co-glycolide)-monomethoxy-poly-(polyethylene glycol) (PLGA-mPEG) nanoparticles to encapsulate melatonin. We tested whether the protective effect of melatonin encapsulated by PLGA-mPEG nanoparticles (melatonin nanoparticles [Mel-NPs]) on adipose-derived mesenchymal stem cells (ADSCs) was enhanced compared to that of free melatonin both in vitro and in vivo. In the in vitro study, we found that Mel-NPs reduced formation of the p53- cyclophilin D complex, prevented mitochondrial permeability transition pores from opening, and rescued ADSCs from hypoxia/reoxygenation injury. Moreover, Mel-NPs can achieve higher ADSC survival rates than free melatonin in rat myocardial infarction areas, and the therapeutic effects of ADSCs pretreated with Mel-NPs were more apparent. Hence, the combination of Mel-NPs and stem cell transplantation may be a promising strategy for myocardial infarction therapy. Stem Cells 2018;36:540-550. © AlphaMed Press 2018.

Effects of a Mangifera indica L. stem bark extract and mangiferin on radiation-induced DNA damage in human lymphocytes and lymphoblastoid cells.

PubMed

Rodeiro, I; Delgado, R; Garrido, G

2014-02-01

Mangifera indica L. (mango) stem bark aqueous extract (MSBE) that has antioxidant, anti-inflammatory and immunomodulatory properties, can be obtained in Cuba. It is rich in polyphenols, where mangiferin is the main component. In this study, we have tested DNA damage and protection effects of MSBE and mangiferin on primary human lymphocytes and lymphoblastoid cells. Cell suspensions were incubated with the products (50-1000 μg/ml) for experiments on damage induction, and evaluation of any potential protective effects (5-100 μg/ml) for 60 min at 37 °C. Irradiation was performed using a γ-ray source, absorbed dose 5 Gy. At the end of exposure, DNA damage, protection and repair processes were evaluated using the comet assay. MSBE (100-1000 μg/ml) induced DNA damage in a concentration dependent manner in both cell types tested, primary cells being more sensitive. Mangiferin (200 μg/ml) only induced light DNA damage at higher concentrations. DNA repair capacity was not affected after MSBE or mangiferin exposure. On the other hand, MSBE (25 and 50 μg/ml) and mangiferin (5-25 ug/ml) protected against gamma radiation-induced DNA damage. These results show MSBE has protector or harmful effects on DNA in vitro depending on the experimental conditions, which suggest that the extract could be acting as an antioxidant or pro-oxidant product. Mangiferin was involved in protective effects of the extract. © 2013 John Wiley & Sons Ltd.

Lithium attenuates lead induced toxicity on mouse non-adherent bone marrow cells.

PubMed

Banijamali, Mahsan; Rabbani-Chadegani, Azra; Shahhoseini, Maryam

2016-07-01

Lead is a poisonous heavy metal that occurs in all parts of environment and causes serious health problems in humans. The aim of the present study was to investigate the possible protective effect of lithium against lead nitrate induced toxicity in non-adherent bone marrow stem cells. Trypan blue and MTT assays represented that exposure of the cells to different concentrations of lead nitrate decreased viability in a dose dependent manner, whereas, pretreatment of the cells with lithium protected the cells against lead toxicity. Lead reduced the number and differentiation status of bone marrow-derived precursors when cultured in the presence of colony stimulating factor (CSF), while the effect was attenuated by lithium. The cells treated with lead nitrate exhibited cell shrinkage, DNA fragmentation, anion superoxide production, but lithium prevented lead action. Moreover, apoptotic indexes such as PARP cleavage and release of HMGB1 induced by lead, were protected by lithium, suggesting anti-apoptotic effect of lithium. Immunoblot analysis of histone H3K9 acetylation indicated that lithium overcame lead effect on acetylation. In conclusion, lithium efficiently reduces lead toxicity suggesting new insight into lithium action which may contribute to increased cell survival. It also provides a potentially new therapeutic strategy for lithium and a cost-effective approach to minimize destructive effects of lead on bone marrow stem cells. Copyright © 2016 Elsevier GmbH. All rights reserved.

Protective effect of arctigenin on ethanol-induced neurotoxicity in PC12 cells.

PubMed

Huang, Jia; Xiao, Lan; Wei, Jing-Xiang; Shu, Ya-Hai; Fang, Shi-Qi; Wang, Yong-Tang; Lu, Xiu-Min

2017-04-01

As a neurotropic substance, ethanol can damage nerve cells through an increase in the production of free radicals, interference of neurotrophic factor signaling pathways, activation of endogenous apoptotic signals and other molecular mechanisms. Previous studies have revealed that a number of natural drugs extracted from plants offer protection of nerve cells from damage. Among these, arctigenin (ATG) is a lignine extracted from Arctium lappa (L.), which has been found to exert a neuroprotective effect on scopolamine‑induced memory deficits in mice with Alzheimer's disease and glutamate-induced neurotoxicity in primary neurons. As a result, it may offer beneficial effects on ethanol-induced neurotoxicity. However, the effects of ATG on ethanol‑induced nerve damage remain to be elucidated. To address this issue, the present study used rat pheochromocytoma PC12 cells to investigate the neuroprotective effects of ATG on ethanol-induced cell damage by performing an MTT reduction assay, cell cycle analysis, Hoechst33342/propidium iodide fluorescence staining and flow cytometry to examine apoptosis. The results showed that 10 µM ATG effectively promoted the proliferation of damaged cells, and increased the distribution ratio of the cells at the G2/M and S phases (P<0.05). In addition, the apoptosis and necrosis of the PC12 cells were significantly decreased following treatment with ATG. Therefore, it was concluded that 10 µM ATG had a protective effect on ethanol‑induced injury in PC12 cells.

Kefiran protects Caco-2 cells from cytopathic effects induced by Bacillus cereus infection.

PubMed

Medrano, Micaela; Hamet, Maria F; Abraham, Analía G; Pérez, Pablo F

2009-11-01

The aim of this work was to evaluate the ability of kefiran to antagonize cytopathic effects triggered by Bacillus cereus strain B10502 on cultured human enterocytes (Caco-2 cells). Cell damage was evaluated by F-actin labelling, scanning electron microscopy and determination of ratios of necrotic and detached cells. To assess the interaction between kefiran and bacteria or eukaryotic cells, flow cytometric analysis was conducted with FITC-labelled kefiran. Kefiran significantly protected infected cells from cytopathic effects induced by B. cereus such as cell necrosis, F-actin disorganisation and microvilli effacement, although presence of kefiran did not modify the adhesion of microorganisms to cultured human enterocytes. Results could be ascribed to the ability of kefiran to interact with both bacteria and eukaryotic cells thus antagonizing interactions necessary for maximal biological effects. Our findings encourage further research on the use of bacterial exopolysaccharides to antagonize virulence factors associated to direct bacteria-cell interactions.

Protection of intestinal damage by pretreatment with cytarabine (cytosine arabinoside)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Phelps, T.A.; Blackett, N.M.

The circumstances in which cytarabine (cytosine arabinoside) ''protects'' intestinal epithelial stem cells against radiation have been investigated. Special attention has been given to this protective effect with radiation doses in the clinically used range in order to determine whether the protective effect might be of use in radiotherapy. It has been shown that 12 hours after cytarabine the D/sub 0/ and extrapolation number are increased when large single doses of radiation are used. To determine the effect of cytarabine at lower doses, it is necessary to use a second irradiation as an ''assay'' dose. By this means it is shownmore » that there is more protection than can be accounted for by the change in D/sub 0/ and extrapolation number at the time of the first dose. Evidence is presented indicating that the rate of stem cell regeneration is not increased by cytarabine pretreatment. Finally, the relation between intestinal protection, bone marrow stem cell enhanced recovery and improved animal survival as a result of cytarabine pretreatment is discussed.« less

Coniferyl Aldehyde Attenuates Radiation Enteropathy by Inhibiting Cell Death and Promoting Endothelial Cell Function

PubMed Central

Son, Yeonghoon; Jang, Jun-Ho; Lee, Yoon-Jin; Kim, Sung-Ho; Ko, Young-Gyo; Lee, Yun-Sil; Lee, Hae-June

2015-01-01

Radiation enteropathy is a common complication in cancer patients. The aim of this study was to investigate whether radiation-induced intestinal injury could be alleviated by coniferyl aldehyde (CA), an HSF1-inducing agent that increases cellular HSP70 expression. We systemically administered CA to mice with radiation enteropathy following abdominal irradiation (IR) to demonstrate the protective effects of CA against radiation-induced gastrointestinal injury. CA clearly alleviated acute radiation-induced intestinal damage, as reflected by the histopathological data and it also attenuated sub-acute enteritis. CA prevented intestinal crypt cell death and protected the microvasculature in the lamina propria during the acute and sub-acute phases of damage. CA induced HSF1 and HSP70 expression in both intestinal epithelial cells and endothelial cells in vitro. Additionally, CA protected against not only the apoptotic cell death of both endothelial and epithelial cells but also the loss of endothelial cell function following IR, indicating that CA has beneficial effects on the intestine. Our results provide novel insight into the effects of CA and suggest its role as a therapeutic candidate for radiation-induced enteropathy due to its ability to promote rapid re-proliferation of the intestinal epithelium by the synergic effects of the inhibition of cell death and the promotion of endothelial cell function. PMID:26029925

Protective effects of lactoferrin against intestinal mucosal damage induced by lipopolysaccharide in human intestinal Caco-2 cells.

PubMed

Hirotani, Yoshihiko; Ikeda, Kenji; Kato, Ryuji; Myotoku, Michiaki; Umeda, Takashi; Ijiri, Yoshio; Tanaka, Kazuhiko

2008-09-01

Indirect evidence suggests that lactoferrin (Lf), a major iron-binding protein in human milk, induces enterocyte growth and proliferation, depending on its concentration and affects the function and permeability of the intestinal mucosa. The bacterial endotoxin (lipopolysaccharide, LPS) is known to cause mucosal hyperpermeability in vivo. However, protective effects of Lf against LPS-mediated intestinal mucosal damage and barrier function in epithelial cells are not yet fully clarified. The aim of this study was to investigate whether Lf can reduce the cellular injury and alter epithelial hyperpermeability caused by LPS in human intestinal Caco-2 cells. When cell viability was measured by a WST-1 assay (tetrazolium salt-based assay), the protective effects against LPS-induced damage to Caco-2 cells were observed at doses of 800 and 1000 microg/ml Lf. The barrier function of Caco-2 monolayer tight junctions was assessed by measuring transepithelial electrical resistance (TEER) and permeability of FITC-labeled dextran 4000 (FD-4). The treatment of Caco-2 cells with Lf at doses of 400 and 1000 microg/ml significantly increased TEER as compared to treatment with LPS alone for 2 h (p<0.05). Further, at doses of 400 and 1000 microg/ml, Lf inhibited the enhancement of LPS-mediated permeability in Caco-2 cell monolayer. The results of this study suggest that Lf may have protective effects against LPS-mediated intestinal mucosal damage and impairment of barrier function in intestinal epithelial cells.

Enteric coated spheres produced by extrusion/spheronization provide effective gastric protection and efficient release of live therapeutic bacteria.

PubMed

de Barros, João M S; Lechner, Tabea; Charalampopoulos, Dimitrios; Khutoryanskiy, Vitaliy V; Edwards, Alexander D

2015-09-30

We present a novel but simple enteric coated sphere formulation containing probiotic bacteria (Lactobacillus casei). Oral delivery of live bacterial cells (LBC) requires live cells to survive firstly manufacturing processes and secondly GI microbicidal defenses including gastric acid. We incorporated live L. casei directly in the granulation liquid, followed by granulation, extrusion, spheronization, drying and spray coating to produce dried live probiotic spheres. A blend of MCC, calcium-crosslinked alginate, and lactose was developed that gave improved live cell survival during manufacturing, and gave excellent protection from gastric acid plus rapid release in intestinal conditions. No significant loss of viability was observed in all steps except drying, which resulted in approximately 1 log loss of viable cells. Eudragit coating was used to protect dried live cells from acid, and microcrystalline cellulose (MCC) was combined with sodium alginate to achieve efficient sphere disintegration leading to rapid and complete bacterial cell release in intestinal conditions. Viability and release of L. casei was evaluated in vitro in simulated GI conditions. Uncoated spheres gave partial acid protection, but enteric coated spheres effectively protected dried probiotic LBC from acid for 2h, and subsequently released all viable cells within 1h of transfer into simulated intestinal fluid. Copyright © 2015 Elsevier B.V. All rights reserved.

Protective effects of C-phycocyanin on alcohol-induced acute liver injury in mice

NASA Astrophysics Data System (ADS)

Xia, Dong; Liu, Bing; Luan, Xiying; Sun, Junyan; Liu, Nana; Qin, Song; Du, Zhenning

2016-03-01

Excessive alcohol consumption leads to liver disease. Extensive evidence suggests that C-phycocyanin (C-PC), a chromophore phycocyanobilin derived from Spirulina platensis, exerts protective effects against chemical-induced organ damage. In this study, we investigated whether C-PC could protect against ethanol-induced acute liver injury. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride (TG), total cholesterol (CHOL), low-density lipoprotein (LDL), liver homogenate malondialdehyde (MDA), superoxide dismutase (SOD) content were measured, and pathological examination of liver sections were examined. C-PC showed obvious inhibitory effects on serum ALT, AST, TG, CHOL, LDL and MDA, and SOD content significantly increased in the liver. The structure of hepatic lobules was clear, liver sinus returned to normal, and liver cell cords were arranged in neat rows. Cloudiness, swelling, inflammatory cell infiltration and spotty necrosis of liver cells were significantly reduced. Therefore, C-PC can significantly protect against ethanol-induced acute liver injury.

Amelioration of streptozotocin‑induced pancreatic β cell damage by morin: Involvement of the AMPK‑FOXO3‑catalase signaling pathway.

PubMed

Wang, Ning; Zhang, Jiahui; Qin, Mengting; Yi, Wenjing; Yu, Shuang; Chen, Yi; Guan, Jing; Zhang, Rui

2018-03-01

Pancreatic β cells are sensitive to oxidative stress, which is one of the predominant causes of cell damage and the emergence of diabetes. The identification of effective therapeutic strategies to protect pancreatic cells from oxidative stress has increased interest in the screening of antioxidants from natural products. The present study aimed to investigate the protective effects of morin against streptozotocin (STZ)‑induced cell damage in a rat insulinoma cell line (RINm5F pancreatic β cells) and to identify the underlying mechanisms. The results indicated that morin inhibited the increase in intracellular reactive oxygen species, attenuated the activity of poly (ADP‑ribose) polymerase, restored intracellular nicotinamide adenine dinucleotide levels and reduced the apoptotic cell death of STZ‑treated pancreatic β cells. Treatment with morin significantly upregulated catalase in pancreatic β cells, and ameliorated the STZ‑induced loss of catalase at the genetic, protein and enzymatic level. In further experiments, morin induced the phosphorylation of 5' adenosine monophosphate‑activated protein kinase (AMPK), which subsequently promoted the translocation of forkhead box O3 (FOXO3) to the nucleus. Specific small interfering RNAs (siRNAs) against AMPK and FOXO3 suppressed morin‑induced catalase expression. Furthermore, catalase‑specific siRNA abolished the protective effects of morin against STZ‑stimulated cell death. Taken together, these results indicated that morin protected RINm5F cells from STZ‑induced cell damage by triggering the phosphorylation of AMPK, thus resulting in subsequent activation of FOXO3 and induction of catalase.

Adoptive Transfer of Dying Cells Causes Bystander-Induced Apoptosis

PubMed Central

Schwulst, Steven J.; Davis, Christopher G.; Coopersmith, Craig M.; Hotchkiss, Richard S.

2009-01-01

The anti-apoptotic Bcl-2 protein has the remarkable ability to prevent cell death from several noxious stimuli. Intriguingly, Bcl-2 overexpression in one cell type has been reported to protect against cell death in neighboring non-Bcl-2 overexpressing cell types. The mechanism of this “trans” protection has been speculated to be secondary to the release of a cytoprotective factor by Bcl-2 overexpressing cells. We employed a series of adoptive transfer experiments in which lymphocytes that overexpress Bcl-2 were administered to either wild type mice or mice lacking mature T and B cells (Rag-1-/-) to detect the presence or absence of the putative protective factor. We were unable to demonstrate “trans” protection. However, adoptive transfer of apoptotic or necrotic cells exacerbated the degree of apoptotic death in neighboring non-Bcl-2 overexpressing cells (p≤0.05). Therefore, this data suggests that dying cells emit signals triggering cell death in neighboring non-Bcl-2 overexpressing cells, i.e. a “trans” destructive effect. PMID:17194455

3-Bromopyruvate antagonizes effects of lactate and pyruvate, synergizes with citrate and exerts novel anti-glioma effects.

PubMed

El Sayed, S M; El-Magd, R M Abou; Shishido, Y; Chung, S P; Diem, T H; Sakai, T; Watanabe, H; Kagami, S; Fukui, K

2012-02-01

Oxidative stress-energy depletion therapy using oxidative stress induced by D-amino acid oxidase (DAO) and energy depletion induced by 3-bromopyruvate (3BP) was reported recently (El Sayed et al., Cancer Gene Ther., 19, 1-18, 2012). Even in the presence of oxygen, cancer cells oxidize glucose preferentially to produce lactate (Warburg effect) which seems vital for cancer microenvironment and progression. 3BP is a closely related structure to lactate and pyruvate and may antagonize their effects as a novel mechanism of its action. Pyruvate exerted a potent H(2)O(2) scavenging effect to exogenous H(2)O(2), while lactate had no scavenging effect. 3BP induced H(2)O(2) production. Pyruvate protected against H(2)O(2)-induced C6 glioma cell death, 3BP-induced C6 glioma cell death but not against DAO/D-serine-induced cell death, while lactate had no protecting effect. Lactate and pyruvate protected against 3BP-induced C6 glioma cell death and energy depletion which were overcome with higher doses of 3BP. Lactate and pyruvate enhanced migratory power of C6 glioma which was blocked by 3BP. Pyruvate and lactate did not protect against C6 glioma cell death induced by other glycolytic inhibitors e.g. citrate (inhibitor of phosphofructokinase) and sodium fluoride (inhibitor of enolase). Serial doses of 3BP were synergistic with citrate in decreasing viability of C6 glioma cells and spheroids. Glycolysis subjected to double inhibition using 3BP with citrate depleted ATP, clonogenic power and migratory power of C6 glioma cells. 3BP induced a caspase-dependent cell death in C6 glioma. 3BP was powerful in decreasing viability of human glioblastoma multiforme cells (U373MG) and C6 glioma in a dose- and time-dependent manner.

Low-dose energetic protons induce adaptive and bystander effects that protect human cells against DNA damage caused by a subsequent exposure to energetic iron ions

PubMed Central

Buonanno, Manuela; De Toledo, Sonia M.; Howell, Roger W.; Azzam, Edouard I.

2015-01-01

During interplanetary missions, astronauts are exposed to mixed types of ionizing radiation. The low ‘flux’ of the high atomic number and high energy (HZE) radiations relative to the higher ‘flux’ of low linear energy transfer (LET) protons makes it highly probable that for any given cell in the body, proton events will precede any HZE event. Whereas progress has been made in our understanding of the biological effects of low-LET protons and high-LET HZE particles, the interplay between the biochemical processes modulated by these radiations is unclear. Here we show that exposure of normal human fibroblasts to a low mean absorbed dose of 20 cGy of 0.05 or 1-GeV protons (LET ∼ 1.25 or 0.2 keV/μm, respectively) protects the irradiated cells (P < 0.0001) against chromosomal damage induced by a subsequent exposure to a mean absorbed dose of 50 cGy from 1 GeV/u iron ions (LET ∼ 151 keV/μm). Surprisingly, unirradiated (i.e. bystander) cells with which the proton-irradiated cells were co-cultured were also significantly protected from the DNA-damaging effects of the challenge dose. The mitigating effect persisted for at least 24 h. These results highlight the interactions of biological effects due to direct cellular traversal by radiation with those due to bystander effects in cell populations exposed to mixed radiation fields. They show that protective adaptive responses can spread from cells targeted by low-LET space radiation to bystander cells in their vicinity. The findings are relevant to understanding the health hazards of space travel. PMID:25805407

Vitamin C and Vitamin E Protected B95-8 and Balb/c-3T3 Cells from Apoptosis Induced by Intermittent 50Hz ELF-EMF Radiation

PubMed Central

DING, Zhen; LI, Jintao; LI, Fan; MEPHRYAR, Mohammadreza Mohammadzad; WU, Shuicai; ZHANG, Chen; ZENG, Yi

2017-01-01

Background: The extremely low-frequency electromagnetic field (ELF-EMF), mainly emitted by electric transmission lines and household electronic appliances, is becoming a worldwide health risk. It is imperative to investigate the biological impacts of ELF-EMF and to identify products that are resistant to the radiation from 50 Hz ELF-EMF. In this study, we investigated the biological impacts of apoptosis caused by 50 Hz Power line ELF-EMF and the protective effects of Vit C and Vit E. Methods: We conducted this study in Beijing, China in 2013. B95-8 and Balb/c-3T3 cells were divided into a sham group, an expo group and 3 expo groups in which the cells were preincubated with various concentrations of Vit C and Vit E. Then, all of the cells were exposed to 50 Hz Power line ELF-EMF and examined for apoptosis. The cells were collected for apoptosis detection after exposure. Results: The percent of cells that undergoing apoptosis and preincubated with various concentrations of Vit C and Vit E were significantly lower than in the Expo group. Conclusion: Vit C and Vit E exert significant protective effects from 50 Hz ELF-EMF radiation. The optimal protective concentrations of Vit C and Vit E are 10 μmol/L and 25 μmol/L, respectively. The protective effect of vitamins was more apparent for Balb/c-3T3 cells than B95-8 cells. PMID:28451526

HIF-1-mediated production of exosomes during hypoxia is protective in renal tubular cells.

PubMed

Zhang, Wei; Zhou, Xiangjun; Yao, Qisheng; Liu, Yutao; Zhang, Hao; Dong, Zheng

2017-10-01

Exosomes are nano-sized vesicles produced and secreted by cells to mediate intercellular communication. The production and function of exosomes in kidney tissues and cells remain largely unclear. Hypoxia is a common pathophysiological condition in kidneys. This study was designed to characterize exosome production during hypoxia of rat renal proximal tubular cells (RPTCs), investigate the regulation by hypoxia-inducible factor-1 (HIF-1), and determine the effect of the exosomes on ATP-depletion-induced tubular cell injury. Hypoxia did not change the average sizes of exosomes secreted by RPTCs, but it significantly increased exosome production in a time-dependent manner. HIF-1 induction with dimethyloxalylglycine also promoted exosome secretion, whereas pharmacological and genetic suppression of HIF-1 abrogated the increase of exosome secretion under hypoxia. The exosomes from hypoxic RPTCs had inhibitory effects on apoptosis of RPTCs following ATP depletion. The protective effects were lost in the exosomes from HIF-1α knockdown cells. It is concluded that hypoxia stimulates exosome production and secretion in renal tubular cells. The exosomes from hypoxic cells are protective against renal tubular cell injury. HIF-1 mediates exosome production during hypoxia and contributes to the cytoprotective effect of the exosomes. Copyright © 2017 the American Physiological Society.

Protection against hydrogen peroxide cytotoxicity in rat-1 fibroblasts provided by the oncoprotein Bcl-2: maintenance of calcium homoeostasis is secondary to the effect of Bcl-2 on cellular glutathione.

PubMed Central

Rimpler, M M; Rauen, U; Schmidt, T; Möröy, T; de Groot, H

1999-01-01

The oncoprotein Bcl-2 protects cells against apoptosis, but the exact molecular mechanism that underlies this function has not yet been identified. Studying H2O2-induced cell injury in Rat-1 fibroblast cells, we observed that Bcl-2 had a protective effect against the increase in cytosolic calcium concentration and subsequent cell death. Furthermore, overexpression of Bcl-2 resulted in an alteration of cellular glutathione status: the total amount of cellular glutathione was increased by about 60% and the redox potential of the cellular glutathione pool was maintained in a more reduced state during H2O2 exposure compared with non-Bcl-2-expressing controls. In our cytotoxicity model, disruption of cellular glutathione homoeostasis closely correlated with the pathological elevation of cytosolic calcium concentration. Stabilization of the glutathione pool by Bcl-2, N-acetylcysteine or glucose delayed the cytosolic calcium increase and subsequent cell death, whereas depletion of glutathione by dl-buthionine-(S, R)-sulphoximine, sensitized Bcl-2-transfected cells towards cytosolic calcium increase and cell death. We therefore suggest that the protection exerted by Bcl-2 against H2O2-induced cytosolic calcium elevation and subsequent cell death is secondary to its effect on the cellular glutathione metabolism. PMID:10229685

Antitumor Effects of Palladium-α-Lipoic Acid Complex Formulation as an Adjunct in Radiotherapy.

PubMed

Veena, Ravindran Kalathil; Ajith, Thekkuttuparambil Ananthanarayanan; Janardhanan, Kainoor Krishnankutty; Antonawich, Francis

2016-01-01

Several investigations have been initiated to enhance the antitumor effect of radiation and ameliorate its adverse effects such as reducing blood cell counts and causing DNA damage in normal cells. Compounds that enhance the antitumor activity of radiation without reducing blood cell counts or damaging DNA in normal cells can be of immense use as an adjunct in radiotherapy. We evaluated the antitumor effect of a specific set of minerals, vitamins, and amino acids (Poly-MVA) (2 mL/kg, per os), with and without radiation, against Dalton's lymphoma ascites (DLA) and Ehrlich's ascites carcinoma (EAC) cell lines that were transplanted in a solid-tumor model. Whole-body γ-radiation exposure (2 Gy) was performed using 60Co. Poly-MVA enhanced the antitumor effect of radiation when administered beforehand. Furthermore, Poly-MVA administered once daily for 2 wk, immediately after 4 Gy irradiation, protected DNA damage in peripheral blood. It also rendered protection against the radiation-induced reduction of platelet count. The unique electronic and redox properties of palladium-α-lipoic acid complex in Poly-MVA appear to be responsible for the exhibited effect. The results conclude that the antitumor-enhancing and normal cell-protective effect of Poly-MVA warrants additional studies for its potential clinical application.

Clusterin protects H9c2 cardiomyocytes from oxidative stress-induced apoptosis via Akt/GSK-3β signaling pathway

PubMed Central

Jun, Hyoung-Oh; Kim, Dong-hun; Lee, Sae-Won; Lee, Hye Shin; Seo, Ji Hae; Kim, Jeong Hun; Kim, Jin Hyoung; Yu, Young Suk; Min, Bon Hong

2011-01-01

Clusterin is a secretory glycoprotein, which is highly up-regulated in a variety of normal and injury tissues undergoing apoptosis including infarct region of the myocardium. Here, we report that clusterin protects H9c2 cardiomyocytes from H2O2-induced apoptosis by triggering the activation of Akt and GSK-3β. Treatment with H2O2 induces apoptosis of H9c2 cells by promoting caspase cleavage and cytochrome c release from mitochondria. However, co-treatment with clusterin reverses the induction of apoptotic signaling by H2O2, thereby recovers cell viability. The protective effect of clusterin on H2O2-induced apoptosis is impaired by PI3K inhibitor LY294002, which effectively suppresses clusterin-induced activation of Akt and GSK-3β. In addition, the protective effect of clusterin is independednt on its receptor megalin, because inhibition of megalin has no effect on clusturin-mediated Akt/GSK-3β phosphoylation and H9c2 cell viability. Collectively, these results suggest that clusterin has a role protecting cardiomyocytes from oxidative stress and the Akt/GSK-3β signaling mediates anti-apoptotic effect of clusterin. PMID:21270507

Salvianolic Acid B (Sal B) Protects Retinal Pigment Epithelial Cells from Oxidative Stress-Induced Cell Death by Activating Glutaredoxin 1 (Grx1)

PubMed Central

Liu, Xiaobin; Xavier, Christy; Jann, Jamieson; Wu, Hongli

2016-01-01

Protein glutathionylation, defined as the formation of protein mixed disulfides (PSSG) between cysteine residues and glutathione (GSH), can lead to cell death. Glutaredoxin 1 (Grx1) is a thiol repair enzyme which catalyzes the reduction of PSSG. Therefore, Grx1 exerts strong anti-apoptotic effects by improving the redox state, especially in times of oxidative stress. However, there is currently no compound that is identified as a Grx1 activator. In this study, we identified and characterized Salvianolic acid B (Sal B), a natural compound, as a Grx1 inducer, which potently protected retinal pigment epithelial (RPE) cells from oxidative injury. Our results showed that treatment with Sal B protected primary human RPE cells from H2O2-induced cell damage. Interestingly, we found Sal B pretreatment upregulated Grx1 expression in RPE cells in a time- and dose-dependent manner. Furthermore, NF-E2-related factor 2 (Nrf2), the key transcription factor that regulates the expression of Grx1, was activated in Sal B treated RPE cells. Further investigation showed that knockdown of Grx1 by small interfering RNA (siRNA) significantly reduced the protective effects of Sal B. We conclude that Sal B protects RPE cells against H2O2-induced cell injury through Grx1 induction by activating Nrf2 pathway, thus preventing lethal accumulation of PSSG and reversing oxidative damage. PMID:27827892

Endothelial microparticle uptake in target cells is annexin I/phosphatidylserine receptor dependent and prevents apoptosis.

PubMed

Jansen, Felix; Yang, Xiaoyan; Hoyer, Friedrich Felix; Paul, Kathrin; Heiermann, Nadine; Becher, Marc Ulrich; Abu Hussein, Nebal; Kebschull, Moritz; Bedorf, Jörg; Franklin, Bernardo S; Latz, Eicke; Nickenig, Georg; Werner, Nikos

2012-08-01

Endothelial microparticles (EMP) are released from activated or apoptotic cells, but their effect on target cells and the exact way of incorporation are largely unknown. We sought to determine the uptake mechanism and the biological effect of EMP on endothelial and endothelial-regenerating cells. EMP were generated from starved endothelial cells and isolated by ultracentrifugation. Caspase 3 activity assay and terminal deoxynucleotidyl transferase dUTP nick end labeling assay showed that EMP protect target endothelial cells against apoptosis in a dose-dependent manner. Proteomic analysis was performed to identify molecules contained in EMP, which might be involved in EMP uptake. Expression of annexin I in EMP was found and confirmed by Western blot, whereas the corresponding receptor phosphatidylserine receptor was present on endothelial target cells. Silencing either annexin I on EMP or phosphatidylserine receptor on target cells using small interfering RNA showed that the uptake of EMP by human coronary artery endothelial cells is annexin I/phosphatidylserine receptor dependent. Annexin I-downregulated EMP abrogated the EMP-mediated protection against apoptosis of endothelial target cells. p38 activation was found to mediate camptothecin-induced apoptosis. Finally, human coronary artery endothelial cells pretreated with EMP inhibited camptothecin-induced p38 activation. EMP are incorporated by endothelial cells in an annexin I/phosphatidylserine receptor-dependent manner and protect target cells against apoptosis. Inhibition of p38 activity is involved in EMP-mediated protection against apoptosis.

The predominant protective effect of tianeptine over other antidepressants in models of neuronal apoptosis: the effect blocked by inhibitors of MAPK/ERK1/2 and PI3-K/Akt pathways.

PubMed

Jantas, D; Krawczyk, S; Lason, W

2014-02-01

Tianeptine (Tian) possesses neuroprotective potential, however, little is known about the effect of this drug in models of neuronal apoptosis. In the present study, we aimed (1) to compare the neuroprotective capacities of some antidepressants (ADs) in the models of staurosporine (St)- and doxorubicin (Dox)-evoked cell death, activating the intracellular and the extracellular apoptotic pathway, respectively; (2) to identify the Tian-modulated steps underlying its neuroprotective action; (3) to test the effect of various ADs against Dox-evoked cell damage in glia cells. Primary neuronal and glia cell cultures and retinoic acid-differentiated human neuroblastoma SH-SY5Y (RA-SH-SY5Y) cells were co-treated with imipramine, fluoxetine, citalopram, reboxetine, mirtazapine or Tian and St or Dox. The data showed the predominant neuroprotective effect of Tian over other tested ADs against St- and Dox-induced cell damage in primary neurons and in RA-SH-SY5Y cells. This effect was shown to be caspase-3-independent but connected with attenuation of DNA fragmentation. Moreover, neuroprotection elicited by Tian was blocked by pharmacological inhibitors of MAPK/ERK1/2 and PI3-K/Akt signaling pathways as well by inhibitor of necroptosis, necrostatin-1. Interestingly, the protective effects of all tested ADs were demonstrated in primary glia cells against the Dox-evoked cell damage. The obtained data suggests the glial cells as a common target for protective action of various ADs whereas in relation to neuronal cells only Tian possesses such properties, at least against St- and Dox-induced cell damage. Moreover, this neuroprotective effect of Tian is caspase-3-independent and engages the regulation of survival pathways (MAPK/ERK1/2 and PI3-K/Akt).

Transduced human copper chaperone for Cu,Zn-SOD (PEP-1-CCS) protects against neuronal cell death.

PubMed

Choi, Soo Hyun; Kim, Dae Won; Kim, So Young; An, Jae Jin; Lee, Sun Hwa; Choi, Hee Soon; Sohn, Eun Jung; Hwang, Seok-Il; Won, Moo Ho; Kang, Tae-Cheon; Kwon, Hyung Joo; Kang, Jung Hoon; Cho, Sung-Woo; Park, Jinseu; Eum, Won Sik; Choi, Soo Young

2005-12-31

Reactive oxygen species (ROS) contribute to the development of various human diseases. Cu,Zn-superoxide dismutase (SOD) is one of the major means by which cells counteract the deleterious effects of ROS. SOD activity is dependent upon bound copper ions supplied by its partner metallochaperone protein, copper chaperone for SOD (CCS). In the present study, we investigated the protective effects of PEP-1-CCS against neuronal cell death and ischemic insults. When PEP-1-CCS was added to the culture medium of neuronal cells, it rapidly entered the cells and protected them against paraquat-induced cell death. Moreover, transduced PEP-1-CCS markedly increased endogenous SOD activity in the cells. Immunohistochemical analysis revealed that it prevented neuronal cell death in the hippocampus in response to transient forebrain ischemia. These results suggest that CCS is essential to activate SOD, and that transduction of PEP-1-CCS provides a potential strategy for therapeutic delivery in various human diseases including stroke related to SOD or ROS.

Agmatine protects Müller cells from high-concentration glucose-induced cell damage via N-methyl-D-aspartic acid receptor inhibition

PubMed Central

HAN, NING; YU, LI; SONG, ZHIDU; LUO, LIFU; WU, YAZHEN

2015-01-01

Neural injury is associated with the development of diabetic retinopathy. Müller cells provide structural and metabolic support for retinal neurons. High glucose concentrations are known to induce Müller cell activity. Agmatine is an endogenous polyamine, which is enzymatically formed in the mammalian brain and has exhibited neuroprotective effects in a number of experimental models. The aims of the present study were to investigate whether agmatine protects Müller cells from glucose-induced damage and to explore the mechanisms underlying this process. Lactate dehydrogenase activity and tumor necrosis factor-α mRNA expression were significantly reduced in Müller cells exposed to a high glucose concentration, following agmatine treatment, compared with cells not treated with agmatine. In addition, agmatine treatment inhibited glucose-induced Müller cell apoptosis, which was associated with the regulation of Bax and Bcl-2 expression. Agmatine treatment suppressed glucose-induced phosphorylation of mitogen-activated protein kinase (MAPK) protein in Müller cells. The present study demonstrated that the protective effects of agmatine on Müller cells were inhibited by N-methyl-D-aspartic acid (NMDA). The results of the present study suggested that agmatine treatment protects Müller cells from high-concentration glucose-induced cell damage. The underlying mechanisms may relate to the anti-inflammatory and antiapoptotic effects of agmatine, as well as to the inhibition of the MAPK pathway, via NMDA receptor suppression. Agmatine may be of use in the development of novel therapeutic approaches for patients with diabetic retinopathy. PMID:25816073

Agmatine protects Müller cells from high-concentration glucose-induced cell damage via N-methyl-D-aspartic acid receptor inhibition.

PubMed

Han, Ning; Yu, Li; Song, Zhidu; Luo, Lifu; Wu, Yazhen

2015-07-01

Neural injury is associated with the development of diabetic retinopathy. Müller cells provide structural and metabolic support for retinal neurons. High glucose concentrations are known to induce Müller cell activity. Agmatine is an endogenous polyamine, which is enzymatically formed in the mammalian brain and has exhibited neuroprotective effects in a number of experimental models. The aims of the present study were to investigate whether agmatine protects Müller cells from glucose-induced damage and to explore the mechanisms underlying this process. Lactate dehydrogenase activity and tumor necrosis factor-α mRNA expression were significantly reduced in Müller cells exposed to a high glucose concentration, following agmatine treatment, compared with cells not treated with agmatine. In addition, agmatine treatment inhibited glucose-induced Müller cell apoptosis, which was associated with the regulation of Bax and Bcl-2 expression. Agmatine treatment suppressed glucose-induced phosphorylation of mitogen-activated protein kinase (MAPK) protein in Müller cells. The present study demonstrated that the protective effects of agmatine on Müller cells were inhibited by N-methyl-D-aspartic acid (NMDA). The results of the present study suggested that agmatine treatment protects Müller cells from high-concentration glucose-induced cell damage. The underlying mechanisms may relate to the anti-inflammatory and antiapoptotic effects of agmatine, as well as to the inhibition of the MAPK pathway, via NMDA receptor suppression. Agmatine may be of use in the development of novel therapeutic approaches for patients with diabetic retinopathy.

β-Cell protection and antidiabetic activities of Crassocephalum crepidioides (Asteraceae) Benth. S. Moore extract against alloxan-induced oxidative stress via regulation of apoptosis and reactive oxygen species (ROS).

PubMed

Bahar, Entaz; Akter, Kazi-Marjahan; Lee, Geum-Hwa; Lee, Hwa-Young; Rashid, Harun-Or; Choi, Min-Kyung; Bhattarai, Kashi Raj; Hossain, Mir Mohammad Monir; Ara, Joushan; Mazumder, Kishor; Raihan, Obayed; Chae, Han-Jung; Yoon, Hyonok

2017-03-29

Medicinal plants are becoming more popular in the treatment of various diseases because of the adverse effects of the current therapy, especially antioxidant plant components such as phenols and flavonoids have a protective role against oxidative stress-induced degenerative diseases like diabetes. Thus, the purpose of this study was to investigate β-cell protection and antidiabetic activities of Crassocephalum crepidioides (Asteraceae) Benth. S. Moore. The in-vitro study was conducted by the pancreatic β-cell culture and α-amylase inhibition technique which includes two methods, namely starch-iodine method and 3,5-dinitrosalicylic acid (DNSA) method. On the other hand, the in-vivo study was performed by oral glucose tolerance test (OGTT) method and alloxan-induced diabetes method by using Wistar albino rat. At the end pancreatic specimens were removed and processed for histopathological study. The plant extract showed significant (*p < 0.05, **p < 0.01) effect on hyperglycemia as compared to standard (Gliclazide) in OGTT. The plant extract showed efficient protection activity of pancreatic β-cell from cell death in INS-1 cell line by significantly reduced (*p < 0.05, **p < 0.01) the levels alloxan-induced apoptosis and intracellular reactive oxygen species (ROS) accumulation. In addition, the plant extract showed a significant (*p < 0.05, **p < 0.01) effect on hyperglycemia by increases in percent of β-cells present in each islet (45% - 60%) compared to the diabetic group. The result showed that C. crepidioides had β-cell protection and antidiabetic activities in pancreatic β-cell culture and Wistar albino rat.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shier, W.T.

Normally a freeze-thaw cycle is a very efficient method of killing mammalian cells. However, this report describes conditions that prevent killing of cultured mammalian cells by nucleated freezing at -24 degrees C. Optimal protection from cell killing at -24 degrees C was obtained in isotonic solutions containing an organic cryoprotectant such as dimethyl sulfoxide (DMSO; 10%, v/v), a saccharide such as sucrose over a broad concentration range from 50 to 150 mM, and glucose. Glycerol was also an effective cryoprotectant but other organic solvents were ineffective, although in some cases they appeared to protect cell membranes, while not protecting othermore » vital components. A wide variety of saccharide structures were effective at protecting cells from freeze-thaw killing, with trehalose being particularly effective. The degree of resistance to killing by a freeze-thaw cycle under these conditions varied widely among different cell lines. If toxicity of DMSO was responsible for this variability of cryoprotection, it must have been due to short-term, not longer term, toxicity of DMSO. Studies on the mechanism by which cells are protected from killing under these conditions indicated that neither vitrification of the medium nor the concentrating of components during freezing were involved. One model not eliminated by the mechanistic studies proposes that the organic solvent cryoprotectant component acts by fluidizing membranes under the thawing conditions, so that any holes produced by ice crystals propagating through membranes can reseal during the thawing process. In this model one of the mechanisms by which the saccharide component could act is by entering the cells and stabilizing vital intracellular components. Consistent with this, a freeze-thaw cycle promoted the uptake of labeled sucrose into cultured cells.« less

Anti-apoptotic effects of Curcuma longa L. extract and its curcuminoids against blue light-induced cytotoxicity in A2E-laden human retinal pigment epithelial cells.

PubMed

Park, Sang-Il; Lee, Eun Hye; Kim, So Ra; Jang, Young Pyo

2017-03-01

The purpose of the study was to investigate the protective effect of the Curcuma longa L. extract (CLE) and its curcuminoids against blue light-induced cytotoxicity in human retinal pigment epithelial (RPE) cells laded with A2E. A2E has been concerned in age-related macular degeneration (AMD). To perform this study, A2E-accumulated ARPE-19 cells were exposed to blue light to induce cytotoxicity. The cytotoxicity and apoptotic gene expression levels were evaluated using a lactate dehydrogenase (LDH) assay and real-time PCR analysis, respectively. Curcuma longa L. extract was found to exert a protective effect in a dose-dependent manner. At a concentration of 15 μm, curcumin, demethoxycurcumin and bisdemethoxycurcumin exerted significant protective effects against blue light-induced cytotoxicity. Treatment with CLE and curcuminoids meaningfully reduced the mRNA levels of c-Abl and p53, which was known to be augmented in apoptotic RPE cells. Demethoxycurcumin and bisdemethoxycurcumin were found to inhibit p38 expression, which is increased in blue light-irradiated A2E-accumulated RPE cells. Curcuma longa L. extract and its curcuminoids provided significant protection against photooxidative damage and apoptosis in the RPE cells. Our results suggest that curcuminoids may show potential in the treatment of AMD. © 2017 Royal Pharmaceutical Society.

Light scattering on PHA granules protects bacterial cells against the harmful effects of UV radiation.

PubMed

Slaninova, Eva; Sedlacek, Petr; Mravec, Filip; Mullerova, Lucie; Samek, Ota; Koller, Martin; Hesko, Ondrej; Kucera, Dan; Marova, Ivana; Obruca, Stanislav

2018-02-01

Numerous prokaryotes accumulate polyhydroxyalkanoates (PHA) in the form of intracellular granules. The primary function of PHA is the storage of carbon and energy. Nevertheless, there are numerous reports that the presence of PHA granules in microbial cells enhances their stress resistance and fitness when exposed to various stress factors. In this work, we studied the protective mechanism of PHA granules against UV irradiation employing Cupriavidus necator as a model bacterial strain. The PHA-accumulating wild type strain showed substantially higher UV radiation resistance than the PHA non-accumulating mutant. Furthermore, the differences in UV-Vis radiation interactions with both cell types were studied using various spectroscopic approaches (turbidimetry, absorption spectroscopy, and nephelometry). Our results clearly demonstrate that intracellular PHA granules efficiently scatter UV radiation, which provides a substantial UV-protective effect for bacterial cells and, moreover, decreases the intracellular level of reactive oxygen species in UV-challenged cells. The protective properties of the PHA granules are enhanced by the fact that granules specifically bind to DNA, which in turn provides shield-like protection of DNA as the most UV-sensitive molecule. To conclude, the UV-protective action of PHA granules adds considerable value to their primary storage function, which can be beneficial in numerous environments.

Autophagy protects gastric mucosal epithelial cells from ethanol-induced oxidative damage via mTOR signaling pathway

PubMed Central

Chang, Weilong; Bai, Jie; Tian, Shaobo; Ma, Muyuan; Li, Wei; Yin, Yuping; Deng, Rui; Cui, Jinyuan; Li, Jinjin; Wang, Guobin; Tao, Kaixiong

2017-01-01

Alcohol abuse is an important cause of gastric mucosal epithelial cell injury and gastric ulcers. A number of studies have demonstrated that autophagy, an evolutionarily conserved cellular mechanism, has a protective effect on cell survival. However, it is not known whether autophagy can protect gastric mucosal epithelial cells against the toxic effects of ethanol. In the present study, gastric mucosal epithelial cells (GES-1 cells) and Wistar rats were treated with ethanol to detect the adaptive response of autophagy. Our results demonstrated that ethanol exposure induced gastric mucosal epithelial cell damage, which was accompanied by the downregulation of mTOR signaling pathway and activation of autophagy. Suppression of autophagy with pharmacological agents resulted in a significant increase of GES-1 cell apoptosis and gastric mucosa injury, suggesting that autophagy could protect cells from ethanol toxicity. Furthermore, we evaluated the cellular oxidative stress response following ethanol treatment and found that autophagy induced by ethanol inhibited generation of reactive oxygen species and degradation of antioxidant and lipid peroxidation. In conclusion, these findings provide evidence that ethanol can activate autophagy via downregulation of the mTOR signaling pathway, serving as an adaptive mechanism to ameliorate oxidative damage induced by ethanol in gastric mucosal epithelial cells. Therefore, modifying autophagy may provide a therapeutic strategy against alcoholic gastric mucosa injury. Impact statement The effect and mechanism of autophagy on ethanol-induced cell damage remain controversial. In this manuscript, we report the results of our study demonstrating that autophagy can protect gastric mucosal epithelial cells against ethanol toxicity in vitro and in vivo. We have shown that ethanol can activate autophagy via downregulation of the mTOR signaling pathway, serving as an adaptive mechanism to ameliorate ethanol-induced oxidative damage in gastric mucosal epithelial cells. This study brings new and important insights into the mechanism of alcoholic gastric mucosal injury and may provide an avenue for future therapeutic strategies. PMID:28056554

M-CSF improves protection against bacterial and fungal infections after hematopoietic stem/progenitor cell transplantation

PubMed Central

Sarrazin, Sandrine; Redelberger, David

2016-01-01

Myeloablative treatment preceding hematopoietic stem cell (HSC) and progenitor cell (HS/PC) transplantation results in severe myeloid cytopenia and susceptibility to infections in the lag period before hematopoietic recovery. We have previously shown that macrophage colony-stimulating factor (CSF-1; M-CSF) directly instructed myeloid commitment in HSCs. In this study, we tested whether this effect had therapeutic benefit in improving protection against pathogens after HS/PC transplantation. M-CSF treatment resulted in an increased production of mature myeloid donor cells and an increased survival of recipient mice infected with lethal doses of clinically relevant opportunistic pathogens, namely the bacteria Pseudomonas aeruginosa and the fungus Aspergillus fumigatus. M-CSF treatment during engraftment or after infection efficiently protected from these pathogens as early as 3 days after transplantation and was effective as a single dose. It was more efficient than granulocyte CSF (G-CSF), a common treatment of severe neutropenia, which showed no protective effect under the tested conditions. M-CSF treatment showed no adverse effect on long-term lineage contribution or stem cell activity and, unlike G-CSF, did not impede recovery of HS/PCs, thrombocyte numbers, or glucose metabolism. These results encourage potential clinical applications of M-CSF to prevent severe infections after HS/PC transplantation. PMID:27811055

Mechanisms of Cross-protection by Influenza Virus M2-based Vaccines.

PubMed

Lee, Yu-Na; Kim, Min-Chul; Lee, Young-Tae; Kim, Yu-Jin; Kang, Sang-Moo

2015-10-01

Current influenza virus vaccines are based on strain-specific surface glycoprotein hemagglutinin (HA) antigens and effective only when the predicted vaccine strains and circulating viruses are well-matched. The current strategy of influenza vaccination does not prevent the pandemic outbreaks and protection efficacy is reduced or ineffective if mutant strains emerge. It is of high priority to develop effective vaccines and vaccination strategies conferring a broad range of cross protection. The extracellular domain of M2 (M2e) is highly conserved among human influenza A viruses and has been utilized to develop new vaccines inducing cross protection against different subtypes of influenza A virus. However, immune mechanisms of cross protection by M2e-based vaccines still remain to be fully elucidated. Here, we review immune correlates and mechanisms conferring cross protection by M2e-based vaccines. Molecular and cellular immune components that are known to be involved in M2 immune-mediated protection include antibodies, B cells, T cells, alveolar macrophages, Fc receptors, complements, and natural killer cells. Better understanding of protective mechanisms by immune responses induced by M2e vaccination will help facilitate development of broadly cross protective vaccines against influenza A virus.

Evaluation of protective and therapeutic effects of dexpanthenol on nasal decongestants and preservatives: results of cytotoxic studies in vitro.

PubMed

Klöcker, Norbert; Rudolph, Peter; Verse, Thomas

2004-01-01

More than 600 million units of nasal decongestants are sold worldwide annually. The cytotoxic and ciliary toxic potential of decongestants, as well as the preservatives of these products, in particular benzalkonium chloride (BKC), is well established. Recently, a beneficial effect of dexpanthenol on the tolerability of the alpha-sympathomimetic xylometazoline and BKC has been described; however, it was unclear if this effect, resulting in significantly higher cell counts in a cytotoxicity study and an increase in ciliary beat frequency in a ciliary toxicity study was of protective or therapeutic nature. The objective of this study was (a) to evaluate whether dexpanthenol would be a useful additive to nasal decongestants to counter the cytotoxic and ciliary toxic effects of the active ingredient and the preservative and (b) to find out whether this beneficial effect is of protective or therapeutic nature. Systematic cytotoxic in vitro tests were performed. After exposure to xylometazoline (0.1%), the effect of dexpanthenol (5%) and BKC (0.01%) was determined by placebo-controlled assessment of cell growth in a human amniotic cell line. Dexpanthenol significantly reduces the toxic effects of xylometazoline regarding cell growth (p < 0.001) when applied in advance. When BKC is eliminated from the nasal sprays, a further significant increase of cell growth was found (p < 0.001). When dexpanthenol is therapeutically applied after xylometazoline, effects on cell growth are only one-half of those of the protective approach. The additive application of dexpanthenol (5%) given before nasal decongestants or preserved nasal sprays is able to improve the tolerability of these substances and to counteract the toxic effects.

Alpha-crystallin-mediated protection of lens cells against heat and oxidative stress-induced cell death.

PubMed

Christopher, Karen L; Pedler, Michelle G; Shieh, Biehuoy; Ammar, David A; Petrash, J Mark; Mueller, Niklaus H

2014-02-01

In addition to their key role as structural lens proteins, α-crystallins also appear to confer protection against many eye diseases, including cataract, retinitis pigmentosa, and macular degeneration. Exogenous recombinant α-crystallin proteins were examined for their ability to prevent cell death induced by heat or oxidative stress in a human lens epithelial cell line (HLE-B3). Wild type αA- or αB-crystallin (WT-αA and WT-αB) and αA- or αB-crystallins, modified by the addition of a cell penetration peptide (CPP) designed to enhance the uptake of proteins into cells (gC-αB, TAT-αB, gC-αA), were produced by recombinant methods. In vitro chaperone-like assays were used to assay the ability of α-crystallins to protect client proteins from chemical or heat induced aggregation. In vivo viability assays were performed in HLE-B3 to determine whether pre-treatment with α-crystallins reduced death after exposure to oxidative or heat stress. Most of the five recombinant α-crystallin proteins tested conferred some in vitro protection from protein aggregation, with the greatest effect seen with WT-αB and gC-αB. All α-crystallins displayed significant protection to oxidative stress induced cell death, while only the αB-crystallins reduced cell death induced by thermal stress. Our findings indicate that the addition of the gC tag enhanced the protective effect of αB-crystallin against oxidative but not thermally-induced cell death. In conclusion, modifications that increase the uptake of α-crystallin proteins into cells, without destroying their chaperone-like activity and anti-apoptotic functions, create the potential to use these proteins therapeutically. Copyright © 2013 Elsevier B.V. All rights reserved.

Memory T cells maintain protracted protection against malaria.

PubMed

Krzych, Urszula; Zarling, Stasya; Pichugin, Alexander

2014-10-01

Immunologic memory is one of the cardinal features of antigen-specific immune responses, and the persistence of memory cells contributes to prophylactic immunizations against infectious agents. Adequately maintained memory T and B cell pools assure a fast, effective and specific response against re-infections. However, many aspects of immunologic memory are still poorly understood, particularly immunologic memory inducible by parasites, for example, Plasmodium spp., the causative agents of malaria. For example, memory responses to Plasmodium antigens amongst residents of malaria endemic areas appear to be either inadequately developed or maintained, because persons who survive episodes of childhood malaria remain vulnerable to intermittent malaria infections. By contrast, multiple exposures of humans and laboratory rodents to radiation-attenuated Plasmodium sporozoites (γ-spz) induce sterile and long-lasting protection against experimental sporozoite challenge. Multifactorial immune mechanisms maintain this protracted and sterile protection. While the presence of memory CD4 T cell subsets has been associated with lasting protection in humans exposed to multiple bites from Anopheles mosquitoes infected with attenuated Plasmodium falciparum, memory CD8 T cells maintain protection induced with Plasmodium yoelii and Plasmodium berghei γ-spz in murine models. In this review, we discuss our observations that show memory CD8 T cells specific for antigens expressed by P. berghei liver stage parasites as an indispensable component for the maintenance of protracted protective immunity against experimental malaria infection; moreover, the provision of an Ag-depot assures a quick recall of memory T cells as IFN-γ-producing effector CD8 T cells and IL-4- producing CD4 T cells that collaborate with B cells for an effective antibody response. Published by Elsevier B.V.

Guanosine protects human neuroblastoma SH-SY5Y cells against mitochondrial oxidative stress by inducing heme oxigenase-1 via PI3K/Akt/GSK-3β pathway.

PubMed

Dal-Cim, Tharine; Molz, Simone; Egea, Javier; Parada, Esther; Romero, Alejandro; Budni, Josiane; Martín de Saavedra, Maria D; del Barrio, Laura; Tasca, Carla I; López, Manuela G

2012-08-01

Mitochondrial perturbation and oxidative stress are key factors in neuronal vulnerability in several neurodegenerative diseases or during brain ischemia. Here we have investigated the protective mechanism of action of guanosine, the guanine nucleoside, in a human neuroblastoma cell line, SH-SY5Y, subjected to mitochondrial oxidative stress. Blockade of mitochondrial complexes I and V with rotenone plus oligomycin (Rot/oligo) caused a significant decrease in cell viability and an increase in ROS production. Guanosine that the protective effect of guanosine incubated concomitantly with Rot/oligo abolished Rot/oligo-induced cell death and ROS production in a concentration dependent manner; maximum protection was achieved at the concentration of 1mM. The cytoprotective effect afforded by guanosine was abolished by adenosine A(1) or A(2A) receptor antagonists (DPCPX or ZM241385, respectively), or by a large (big) conductance Ca(2+)-activated K(+) channel (BK) blocker (charybdotoxin). Evaluation of signaling pathways showed that the protective effect of guanosine was not abolished by a MEK inhibitor (PD98059), by a p38(MAPK) inhibitor (SB203580), or by a PKC inhibitor (cheleritrine). However, when blocking the PI3K/Akt pathway with LY294002, the neuroprotective effect of guanosine was abolished. Guanosine increased Akt and p-Ser-9-GSK-3β phosphorylation confirming this pathway plays a key role in guanosine's neuroprotective effect. Guanosine induced the antioxidant enzyme heme oxygenase-1 (HO-1) expression. The protective effects of guanosine were prevented by heme oxygenase-1 inhibitor, SnPP. Moreover, bilirubin, an antioxidant and physiologic product of HO-1, is protective against mitochondrial oxidative stress. In conclusion, our results show that guanosine can afford protection against mitochondrial oxidative stress by a signaling pathway that implicates PI3K/Akt/GSK-3β proteins and induction of the antioxidant enzyme HO-1. Copyright © 2012 Elsevier Ltd. All rights reserved.

Inhibition of UV-B induced apoptosis in corneal epithelial cells by potassium channel modulators.

PubMed

Ubels, John L; Schotanus, Mark P; Bardolph, Susan L; Haarsma, Loren D; Koetje, Leah R; Louters, Julienne R

2010-02-01

The goal of this study was to determine whether prevention of K(+) loss can protect human corneal-limbal epithelial (HCLE) cells from UV-B induced apoptosis. Immunostaining for activated caspase-3 of HCLE cells exposed to 150-200 mJ/cm(2) UV-B demonstrated induction of apoptosis 6 h after exposure. The number of apoptotic cells was decreased by incubation in medium with 25 or 100 mM K(+). If this protection is due to a reduction of UV-induced K(+) loss then K(+) channel blockers should also protect HCLE cells from UV-B. Caspase-8 activity induced by exposure to UV-B at 150 mJ/cm(2) was significantly reduced when the cells were incubated in 0.3 microM BDS-I or 0.05-1 mM quinidine. Caspase-3 was also activated by UV-B and a reduction in activity was observed after incubation in 0.1-0.3 microM BDS-I and 0.1-1 mM quinidine. Induction of DNA fragmentation, as measured by the TUNEL assay, was decreased by treatment with 0.3 microM BDS-I and 0.01-0.05 mM quinidine. Patch-clamp recording showed activation of K(+) channels after exposure to UV-B and a decrease in outward K(+) current was observed following application of BDS-I. Quinidine did not block K(+) currents in HCLE cells, suggesting that the protective effect of quinidine occurs by a mechanism other than via K(+) channels. The effect of the K(+) channel blocker BDS-1 on HCLE cells exposed to UV-B confirms that preventing K(+) efflux protects corneal epithelial cells from apoptosis. This suggests the elevated [K(+)] in tears may protect the corneal epithelium from effects of ambient UV-B. Copyright 2009 Elsevier Ltd. All rights reserved.

Inhibition of UV-B Induced Apoptosis in Corneal Epithelial Cells by Potassium Channel Modulators

PubMed Central

Ubels, John L.; Schotanus, Mark P.; Bardolph, Susan L.; Haarsma, Loren D.; Koetje, Leah R.; Louters, Julienne R.

2009-01-01

The goal of this study was to determine whether prevention of K+ loss can protect human corneal-limbal epithelial (HCLE) cells from UV-B induced apoptosis. Immunostaining for activated caspase-3 of HCLE cells exposed to 150 – 200 mJ/cm2 UV-B demonstrated induction of apoptosis 6 hrs after exposure. The number of apoptotic cells was decreased by incubation in medium with 25 or 100 mM K+. If this protection is due to a reduction of UV induced K+ loss then K+ channel blockers should also protect HCLE cells from UV-B. Caspase-8 activity induced by exposure to UV-B at 150 mJ/cm2 was significantly reduced when the cells were incubated in 0.3 µM BDS-I or 0.05–1 mM quinidine. Caspase-3 was also activated by UV-B and a reduction in activity was observed after incubation in 0.1–0.3 µM BDS-I and 0.1–1mM quinidine. Induction of DNA fragmentation, as measured by the TUNEL assay, was decreased by treatment with 0.3 µM BDS-I and 0.01–0.05 mM quinidine. Patch-clamp recording showed activation of K+ channels after exposure to UV-B and a decrease in outward K+ current was observed following application of BDS-I. Quinidine did not block K+ currents in HCLE cells, suggesting that the protective effect of quinidine occurs by a mechanism other than via K+ channels. The effect of the K+ channel blocker BDS-1 on HCLE cells exposed to UV-B confirms that preventing K+ efflux protects corneal epithelial cells from apoptosis. This suggests the elevated [K+] in tears may protect the corneal epithelium from effects of ambient UV-B. PMID:19874821

A novel domain of amino-Nogo-A protects HT22 cells exposed to oxygen glucose deprivation by inhibiting NADPH oxidase activity.

PubMed

Guo, Fan; Wang, Huiwen; Li, Liya; Zhou, Heng; Wei, Haidong; Jin, Weilin; Wang, Qiang; Xiong, Lize

2013-04-01

This study aimed to investigate the protective effect of the M9 region (residues 290-562) of amino-Nogo-A fused to the human immunodeficiency virus trans-activator TAT in an in vitro model of ischemia-reperfusion induced by oxygen-glucose deprivation (OGD) in HT22 hippocampal neurons, and to investigate the role of NADPH oxidase in this protection. Transduction of TAT-M9 was analyzed by immunofluorescence staining and western blot. The biologic activity of TAT-M9 was assessed by its effects against OGD-induced HT22 cell damage, compared with a mutant M9 fusion protein or vehicle. Cellular viability and lactate dehydrogenase (LDH) release were assessed. Neuronal apoptosis was evaluated by flow cytometry. The Bax/Bcl-2 ratio was determined by western blotting. Reactive oxygen species (ROS) levels and NADPH oxidase activity were also measured in the presence or absence of an inhibitor or activator of NADPH oxidase. Our results confirmed the delivery of the protein into HT22 cells by immunofluorescence and western blot. Addition of 0.4 μmol/L TAT-M9 to the culture medium effectively improved neuronal cell viability and reduced LDH release induced by OGD. The fusion protein also protected HT22 cells from apoptosis, suppressed overexpression of Bax, and inhibited the reduction in Bcl-2 expression. Furthermore, TAT-M9, as well as apocynin, decreased NADPH oxidase activity and ROS content. The protective effects of the TAT-M9 were reversed by TBCA, an agonist of NADPH oxidase. In conclusion, TAT-M9 could be successfully transduced into HT22 cells, and protected HT22 cells against OGD damage by inhibiting NADPH oxidase-mediated oxidative stress. These findings suggest that the TAT-M9 protein may be an efficient therapeutic agent for neuroprotection.

Protective Effect of Neuropeptide Apelin-13 on 6-Hydroxydopamine-Induced Neurotoxicity in SH-SY5Y Dopaminergic Cells: Involvement of Its Antioxidant and Antiapoptotic Properties.

PubMed

Pouresmaeili-Babaki, Elham; Esmaeili-Mahani, Saeed; Abbasnejad, Mehdi; Ravan, Hadi

2018-04-01

Parkinson's disease (PD) is a severe neurodegenerative disorder characterized by the loss of brain dopaminergic neurons. Beside pharmacologic and symptomatic treatment of PD the neuroprotective therapy has recently attracted more attention. Apelin, a novel neuropeptide, and its receptors have numerous reported roles in regulating brain functions. In addition, this peptide has potent neuroprotective effects in some neurodegenerative situations. In this study, the effects of apelin-13 were investigated in a cell model of PD. Human neuroblastoma SH-SY5Y cell damage was induced by 150 μM 6-hydroxydopamine (6-OHDA) and the cells viability was examined by MTT assay. Intracellular reactive oxygen species (ROS) and mitochondrial membrane potential were determined by fluorescence spectrophotometry method. Immunoblotting analysis was also employed to evaluate cytochrome c release and caspase-3 activity. Data showed that 6-OHDA could decrease cell viability and mitochondrial membrane potential and increase intracellular ROS, cytochrome c, and cleaved caspase-3 levels. Pretreatment of SH-SY5Y cells with apelin-13 (5 and 10 nM) significantly prevented the mentioned biochemical and molecular markers of 6-OHDA-induced neurotoxicity. Furthermore, the results showed that apelin receptor and PI3K signaling contributed to the observed protective effects of apelin. The results suggest that apelin-13 has protective effects against dopaminergic neural toxicity and its antioxidant and antiapoptotic properties are involved, at least in part, in such protection.

Protective effects of melatonin and memantine in human retinal pigment epithelium (ARPE-19) cells against 2-ethylpyridine-induced oxidative stress: implications for age-related macular degeneration.

PubMed

Bardak, Handan; Uğuz, Abdülhadi Cihangir; Bardak, Yavuz

2018-06-01

To investigate the possible protective effects of melatonin and memantine (MMT) against 2-ethylpyridine (2-EP)-induced oxidative stress and mitochondrial dysfunction in human RPE (ARPE-19) cells in vitro. The ARPE-19 cells were divided into seven groups. Oxidative stress was triggered by incubating the ARPE-19 cells with 30 μM of 2-EP for 24 h. Then, 200 μM of melatonin was administered over three days and 20 μM of MMT over six hours prior to the experiment. The effects of melatonin and MMT on the intracellular calcium release mechanism, reactive oxygen species production, caspase-3 and caspase-9 activities, as well as vascular endothelial growth factor levels were measured. Melatonin and MMT were found to significantly decrease apoptosis levels. The intracellular calcium release was regulated by both melatonin and MMT. Further, melatonin and MMT significantly decreased both caspase-3 and caspase-9 activities, as well as pro-caspase and poly(ADP-ribose) polymerase expression, in ARPE-19 cells. Moreover, melatonin significantly increased the protective effect of MMT. The combination of melatonin and MMT significantly decreased 2-EP-induced oxidative toxicity and apoptosis by inhibiting the intracellular reactive oxygen species production and mitochondrial depolarization levels. These notable findings are the first to demonstrate the synergistic protective effects of melatonin and MMT against 2-EP-induced oxidative stress in ARPE-19 cells.

Protective effects of pioglitazone on vascular endothelial cell dysfunction induced by high glucose via inhibition of IKKα/β-NFκB signaling mediated by PPARγ in vitro.

PubMed

Chen, Chunxiang; Peng, Shaorong; Chen, Fanghui; Liu, Lili; Li, Zhouxue; Zeng, Guohua; Huang, Qiren

2017-12-01

PIO, a synthetic ligand for PPARγ, is used clinically to treat T2DM. However, little is known about its protective effects on endothelium and the underlying mechanisms. In this study, we sought to investigate the protective effects of PIO on endothelium and its probable mechanisms: 95% confluent wild type (WT) HUVECs and PPARγ Low -HUVECs that we first injured with HG (33 mmol·L -1 ) were first pretreated with 10 μmol·L -1 of GW9662 for 30 min, and then treated the cells with different concentrations of PIO (5, 10, or 20 μmol·L -1 ) for 24 h. Finally, we measured the levels of NO, ET1, TNFα, and IL6 in the cell culture supernatant. These cells were then used to determine cell viability, caspase3 activity, the levels of IKKα/β mRNA, IKKα/β, and NFκB-p65. Severe dysfunction and activation of IKKα/β-NFκB signaling occurred after we exposed HUVECs to HG. Conversely, treatment with PIO significantly attenuated the dysfunction and the activation of IKKα/β-NFκB signaling induced by HG in a dose-dependent manner. Moreover, the protective effects of PIO were completely abrogated by GW9662 or down-regulation of PPARγ. Taken together, the results indicate that PIO protects HUVECs against the HG-induced dysfunction through the inhibition of IKKα/β-NFκB signaling mediated by PPARγ.

Protective effect of enzymatic hydrolysates from highbush blueberry (Vaccinium corymbosum L.) against hydrogen peroxide-induced oxidative damage in Chinese hamster lung fibroblast cell line

PubMed Central

Senevirathne, Mahinda; Kim, Soo-Hyun

2010-01-01

Blueberry was enzymatically hydrolyzed using selected commercial food grade carbohydrases (AMG, Celluclast, Termamyl, Ultraflo and Viscozyme) and proteases (Alcalase, Flavourzyme, Kojizyme, Neutrase and Protamex) to obtain water soluble compounds, and their protective effect was investigated against H2O2-induced damage in Chinese hamster lung fibroblast cell line (V79-4) via various published methods. Both AMG and Alcalase hydrolysates showed higher total phenolic content as well as higher cell viability and ROS scavenging activities, and hence, selected for further antioxidant assays. Both AMG and Alcalase hydrolysates also showed higher protective effects against lipid peroxidation, DNA damage and apoptotic body formation in a dose-dependent fashion. Thus, the results indicated that water soluble compounds obtained by enzymatic hydrolysis of blueberry possess good antioxidant activity against H2O2-induced cell damage in vitro. PMID:20607062

Protective effect of enzymatic hydrolysates from highbush blueberry (Vaccinium corymbosum L.) against hydrogen peroxide-induced oxidative damage in Chinese hamster lung fibroblast cell line.

PubMed

Senevirathne, Mahinda; Kim, Soo-Hyun; Jeon, You-Jin

2010-06-01

Blueberry was enzymatically hydrolyzed using selected commercial food grade carbohydrases (AMG, Celluclast, Termamyl, Ultraflo and Viscozyme) and proteases (Alcalase, Flavourzyme, Kojizyme, Neutrase and Protamex) to obtain water soluble compounds, and their protective effect was investigated against H(2)O(2)-induced damage in Chinese hamster lung fibroblast cell line (V79-4) via various published methods. Both AMG and Alcalase hydrolysates showed higher total phenolic content as well as higher cell viability and ROS scavenging activities, and hence, selected for further antioxidant assays. Both AMG and Alcalase hydrolysates also showed higher protective effects against lipid peroxidation, DNA damage and apoptotic body formation in a dose-dependent fashion. Thus, the results indicated that water soluble compounds obtained by enzymatic hydrolysis of blueberry possess good antioxidant activity against H(2)O(2)-induced cell damage in vitro.

Protection by [6]-shogaol against lipopolysaccharide-induced toxicity in murine astrocytes is related to production of brain-derived neurotrophic factor.

PubMed

Shim, Sehwan; Kim, Sokho; Kwon, Young-Bae; Kwon, Jungkee

2012-03-01

[6]-Shogaol has beneficial effects in spinal neuronal regeneration, but associated molecules and mechanisms are not identified. Neurotrophic factors, including brain-derived neurotrophic factor (BDNF), are associated with proliferation and differentiation of neuronal cells and exert a neuroprotective effect in neurodegenerative models. We investigated whether treatment with [6]-shogaol increases BDNF expression in lipopolysaccharide (LPS)-treated astrocytes, and examined the effect of [6]-shogaol on neuronal protection. [6]-Shogaol significantly attenuated the cell death induced by LPS. Western blotting showed that [6]-shogaol treatment reduced Bax expression and increased B-cell lymphoma (Bcl)-2 and BclxL expression in LPS-treated cells, consistent with the effects of BDNF treatment. Furthermore, K252a, a blocker of neurotrophic factors, attenuated the cellular protective effects of [6]-shogaol and BDNF. This study provides the first evidence that [6]-shogaol increases the expression of BDNF in LPS-treated astrocytes. Furthermore, these experimental results indicate that production of BDNF in astrocytes might be related to altered cell viability following [6]-shogaol treatment. Thus, the neuroprotective effects of [6]-shogaol is mediated by up-regulation of BDNF. Copyright © 2011 Elsevier Ltd. All rights reserved.

Curculigo orchioides protects cisplatin-induced cell damage.

PubMed

Kang, Tong Ho; Hong, Bin Na; Jung, Su-Young; Lee, Jeong-Han; So, Hong-Seob; Park, Raekil; You, Yong-Ouk

2013-01-01

Cisplatin is commonly used as a chemotherapeutic agent against many human cancers. However, it generates reactive oxygen species (ROS) and has serious dose-limiting side effects, including ototoxicity. The roots of Curculigo orchioides (C. orchioides) have been used to treat auditory diseases such as tinnitus and hearing loss in Chinese traditional medicine. In the present study, we investigated the protective effects of an ethanol extract obtained from C. orchioides rhizome (COR) on cisplatin-induced cell damage in auditory cells (HEI-OC1). COR (2.5-25 μg/ml) inhibited cisplatin-induced HEI-OC1 cell damage in a dose-dependent manner. To investigate the protective mechanism of COR on cisplatin cytotoxicity in HEI-OC1 cells, we measured the effects of COR on ROS generation and lipid peroxidation in cisplatin-treated cells as well as its scavenging activities against superoxide radicals, hydroxyl radicals, hydrogen peroxide, and DPPH radicals. COR (1-25 μg/ml) had scavenging activities against superoxide radicals, hydroxyl radicals, hydrogen peroxide, and DPPH radicals, as well as reduced lipid peroxidation. In in vivo experiments, COR was shown to reduce cochlear and peripheral auditory function impairments through cisplatin-induced auditory damage in mice. These results indicate that COR protects from cisplatin-induced auditory damage by inhibiting lipid peroxidation and scavenging activities against free radicals.

Genetic immunization based on the ubiquitin-fusion degradation pathway against Trypanosoma cruzi

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chou, Bin; Department of Parasitology, Graduate School of Medical Science, Kyushu University, Fukuoka 812-8582; Hiromatsu, Kenji, E-mail: khiromatsu@fukuoka-u.ac.jp

2010-02-12

Cytotoxic CD8{sup +} T cells are particularly important to the development of protective immunity against the intracellular protozoan parasite, Trypanosoma cruzi, the etiological agent of Chagas disease. We have developed a new effective strategy of genetic immunization by activating CD8{sup +} T cells through the ubiquitin-fusion degradation (UFD) pathway. We constructed expression plasmids encoding the amastigote surface protein-2 (ASP-2) of T. cruzi. To induce the UFD pathway, a chimeric gene encoding ubiquitin fused to ASP-2 (pUB-ASP-2) was constructed. Mice immunized with pUB-ASP-2 presented lower parasitemia and longer survival period, compared with mice immunized with pASP-2 alone. Depletion of CD8{sup +}more » T cells abolished protection against T. cruzi in mice immunized with pUB-ASP-2 while depletion of CD4{sup +} T cells did not influence the effective immunity. Mice deficient in LMP2 or LMP7, subunits of immunoproteasomes, were not able to develop protective immunity induced. These results suggest that ubiquitin-fused antigens expressed in antigen-presenting cells were effectively degraded via the UFD pathway, and subsequently activated CD8{sup +} T cells. Consequently, immunization with pUB-ASP-2 was able to induce potent protective immunity against infection of T. cruzi.« less

Cytoprotective Mechanisms Mediated by Polyphenols from Chilean Native Berries against Free Radical-Induced Damage on AGS Cells

PubMed Central

Theoduloz, Cristina; López-Alarcón, Camilo; Dorta, Eva

2017-01-01

The prevalence of cytoprotective mechanisms induced by polyphenols such as activation of intracellular antioxidant responses (ICM) and direct free radical scavenging was investigated in native Chilean species of strawberries, raspberries, and currants. Human gastric epithelial cells were co- and preincubated with polyphenolic-enriched extracts (PEEs) from Chilean raspberries (Rubus geoides), strawberries (Fragaria chiloensis ssp. chiloensis f. chiloensis), and currants (Ribes magellanicum) and challenged with peroxyl and hydroxyl radicals. Cellular protection was determined in terms of cell viability, glyoxalase I and glutathione s-transferases activities, and carboxymethyl lysine (CML) and malondialdehyde levels. Our results indicate that cytoprotection induced by ICM was the prevalent mechanism for Rubus geoides and F. chiloensis. This agreed with increased levels of glyoxalase I and glutathione S-transferase activities in cells preincubated with PEEs. ORAC index indicated that F. chiloensis was the most efficient peroxyl radical scavenger. Moreover, ICM mediated by F. chiloensis was effective in protecting cells from CML accumulation in contrast to the protective effects induced by free radical scavenging. Our results indicate that although both polyphenol-mediated mechanisms can exert protective effects, ICM was the most prevalent in AGS cells. These results suggest a potential use of these native berries as functional food. PMID:28553436

Selective protection of cultured human cells from the toxic effects of ultraviolet light by proflavine pretreatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Williams, J.R.; Little, J.B.

1977-10-01

Pretreatment of LICH human cells by nontoxic doses (0.1 to 5.0 ..mu..g/ml) of proflavine protects them from inactivation by ultraviolet light. The protection is acquired rapidly after exposure of cells to proflavine, with 50 percent of maximum protection being afforded within 5 min and cells being maximally protected by 20 min. Loss of protection follows similar kinetics upon removal of proflavine from the culture medium. Protection is selective and cannot be explained on the basis of proflavine absorption of uv light. Cellular survival curves after ultraviolet light for cells protected by 1, 2, 3, 4, or 5 ..mu..g/ml of proflavinemore » show that protection alters only the slope of the survival curve, not altering the quasi-threshold dose, D/sub q/. The D/sub 0/ varies from 4.8 J/m/sup 2/ for untreated cells to 10.5 J/m/sup 2/ for cells pretreated with 5 ..mu..g/ml. These data suggest the D/sub 0/ and D/sub q/ do not represent parameters of a single underlying process, manifested in a random stochastic manner, but may reflect different cellular mechanisms or responses to different DNA damage. Proflavine is selective in mitigating only those which predominate at uv doses greater than the D/sub q/.« less

PACAP Protects Against Ethanol and Nicotine Toxicity in SH-SY5Y Cells: Implications for Drinking-Smoking Co-morbidity.

PubMed

Manavalan, Sridharan; Getachew, Bruk; Manaye, Kebreten F; Khundmiri, Syed J; Csoka, Antonei B; McKinley, Raechel; Tamas, Andrea; Reglodi, Dora; Tizabi, Yousef

2017-07-01

The detrimental effects of heavy drinking and smoking are multiplied when the two are combined. Treatment modalities for each and especially for the combination are very limited. Although in low concentration, alcohol and nicotine, each may have beneficial effects including neuroprotection, their combination, instead of providing additive protection, may actually lead to toxicity in cell cultures. Pituitary adenylate cyclase-activating polypeptide (PACAP) is an endogenous 38 amino-acid peptide with demonstrated protection against neuronal injury, trauma as well as various endogenous and exogenous toxic agents. The aim of this study was to investigate whether PACAP may also protect against toxicity induced by high alcohol, high nicotine, or the combination of low alcohol and nicotine concentrations, and if so, whether this effect was mediated via PAC1 receptor. We used the neuroblastoma-derived SH-SY5Y cells and applied various colorimetric assays for determination of cell viability or toxicity. Results indicate that PACAP blocks toxicity induced by high alcohol and high nicotine as well as their combination at low concentrations. The effects of PACAP in turn were blocked by the PACAP antagonist (PACAP 6-38), indicating involvement of the PACAP receptor PAC1 and possibly vasoactive intestinal peptide (VIP) receptors in PACAP's protection. Moreover, no combined toxicity of low alcohol and low nicotine could be detected in calcium-free medium. These findings suggest possible beneficial effects of PACAP in preventing alcohol and nicotine toxicity and that calcium contributes to the damage induced by combination of low alcohol and nicotine in SH-SY5Y cells.

The mechanisms of the protective effects of reconstituted skim milk during convective droplet drying of lactic acid bacteria.

PubMed

Zheng, Xufeng; Fu, Nan; Duan, Manlei; Woo, Meng Wai; Selomulya, Cordelia; Chen, Xiao Dong

2015-10-01

Reconstituted skim milk (RSM) is a reputed protective carrier for improving the survival ratio of lactic acid bacteria (LAB) after spray drying; however the underlying mechanisms of the prominent protection remains unclear. In this study, the inactivation histories of two LAB strains during droplet drying with four carriers were experimentally determined, and the effects of droplet drying parameters on LAB inactivation were investigated. For the first time, the possible contribution of each RSM components to the maintenance of LAB viability during drying was discussed. Rapid inactivation of LAB cells only started at the later stage of drying, where RSM could maintain viability better upon both high droplet temperature and low moisture content than the other three carriers tested. Such protective effects was attributed to calcium and milk proteins rather than lactose. Upon the rapidly increasing droplet temperature at the later stage, calcium might enhance the heat resistance of LAB cells, whereas proteins might lead to a mild temperature variation rate which was beneficial to cell survival. LAB cells dried in the reconstituted whole milk showed the most advanced transition of rapid viability loss, with transition temperature at around 60°C, in contrast to 65-70°C in lactose and MRS carriers and 75°C in the RSM carrier. The detrimental effects could be due to the high level of milk fat content. The proposed effects of each RSM components on LAB viability would be useful for constructing more powerful protectants for production of active dry LAB cells via spray drying. Copyright © 2015 Elsevier Ltd. All rights reserved.

Electrochemically Reduced Water Protects Neural Cells from Oxidative Damage

PubMed Central

Hamasaki, Takeki; Kinjo, Tomoya; Nakamichi, Noboru; Teruya, Kiichiro; Kabayama, Shigeru

2014-01-01

Aging-related neurodegenerative disorders are closely associated with mitochondrial dysfunction and oxidative stresses and their incidence tends to increase with aging. Brain is the most vulnerable to reactive species generated by a higher rate of oxygen consumption and glucose utilization compared to other organs. Electrochemically reduced water (ERW) was demonstrated to scavenge reactive oxygen species (ROS) in several cell types. In the present study, the protective effect of ERW against hydrogen peroxide (H2O2) and nitric oxide (NO) was investigated in several rodent neuronal cell lines and primary cells. ERW was found to significantly suppress H2O2 (50–200 μM) induced PC12 and SFME cell deaths. ERW scavenged intracellular ROS and exhibited a protective effect against neuronal network damage caused by 200 μM H2O2 in N1E-115 cells. ERW significantly suppressed NO-induced cytotoxicity in PC12 cells despite the fact that it did not have the ability to scavenge intracellular NO. ERW significantly suppressed both glutamate induced Ca2+ influx and the resulting cytotoxicity in primary cells. These results collectively demonstrated for the first time that ERW protects several types of neuronal cells by scavenging ROS because of the presence of hydrogen and platinum nanoparticles dissolved in ERW. PMID:25383141

Targeting Oct2 and P53: Formononetin prevents cisplatin-induced acute kidney injury

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Di

Nephrotoxicity is one of major side effects of cisplatin in chemotherapy. Therefore, there is an urgent medical need to develop drugs that may protect kidney from toxicity. In previous study, we found that it showed the protective effects of formononetin against apoptosis by upregulating Nrf2. In this study, we investigated the renoprotective effect of formononetin against cisplatin-induced AKI and tried to elucidate the possible mechanisms. The amelioration of renal function, histopathological changes, and apoptosis in tubular cells was observed after formononetin treatment. Formononetin decreased expression of organic cation transporter 2 (Oct2) and increased the expressions of multidrug resistance-associated proteins (Mrps),more » which might result in a decrease accumulation of cisplatin in tubular cells after AKI. 5-Bromo-2-deoxyuridine (BrdU) and Ki-67 staining assay indicated that formononetin could promote the renal tubular cells proliferation after cisplatin nephrotoxicity. Moreover, formononetin regulated cyclins and pro-apoptotic proteins to involve the regulation of cell cycle. Furthermore, formononetin decreased p53 expression via promoting the overexpression of murine double minute 2 (MDM2) and MDMX. Taken together, formononetin provided protective effects by promoting proliferation of surviving renal tubular cells and inhibiting apoptosis after cisplatin-induced AKI. - Highlights: • Formononetin ameliorated the cisplatin-induced AKI. • Oct2 were reduced by formononetin. • Protective effect of formononetin was closely related to the reduction of cisplatin.« less

Synthetic Protection Short Interfering RNA Screen Reveals Glyburide as a Novel Radioprotector

PubMed Central

Jiang, Jianfei; McDonald, Peter R.; Dixon, Tracy M.; Franicola, Darcy; Zhang, Xichen; Nie, Suhua; Epperly, Laura D.; Huang, Zhentai; Kagan, Valerian E.; Lazo, John S.; Epperly, Michael W.; Greenberger, Joel S.

2009-01-01

To assist in screening existing drugs for use as potential radioprotectors, we used a human unbiased 16,560 short interfering RNA (siRNA) library targeting the druggable genome. We performed a synthetic protection screen that was designed to identify genes that, when silenced, protected human glioblastoma T98G cells from γ-radiation-induced cell death. We identified 116 candidate protective genes, then identified 10 small molecule inhibitors of 13 of these candidate gene products and tested their radioprotective effects. Glyburide, a clinically used second-generation hypoglycemic drug, effectively decreased radiation-induced cell death in several cell lines including T98G, glioblastoma U-87 MG, and normal lung epithelial BEAS-2B and in primary cultures of astrocytes. Glyburide significantly increased the survival of 32D cl3 murine hematopoietic progenitor cells when administrated before irradiation. Glyburide was radioprotective in vivo (90% of C57BL/6NHsd female mice pretreated with 10 mg/kg glyburide survived 9.5 Gy total-body irradiation compared to 42% of irradiated controls, P = 0.0249). These results demonstrate the power of unbiased siRNA synthetic protection screening with a druggable genome library to identify new radioprotectors. PMID:19772462

Protective Effects and Mechanism of Meretrix meretrix Oligopeptides against Nonalcoholic Fatty Liver Disease

PubMed Central

Huang, Fangfang; Zhao, Shasha; Yu, Fangmiao; Yang, Zuisu; Ding, Guofang

2017-01-01

Meretrix meretrix oligopeptides (MMO) derived from shellfish have important medicinal properties. We previously obtained MMO from alcalase by hydrolysis processes. Here we examine the protective effects of MMO against nonalcoholic fatty liver disease (NAFLD) and explored the underlying mechanism. Human Chang liver cells were used in our experiments after exposure to palmitic acid at a final concentration of 15 μg/mL for 48 h to induce an overload of fatty acid as NAFLD model cells. Treatment with MMO for 24 h increased the viability of the NAFLD model cells by inhibiting apoptosis. MMO alleviated oxidative stress in the NAFLD model cells by preserving reactive oxygen species activity and increasing malondialdehyde and superoxide dismutase activity. MMO improved mitochondrial dysfunction by decreasing the mitochondrial membrane potential and increasing the activities of Na+/K+-ATPase and Ca2+/Mg2+-ATPase. In addition, MMO inhibited the activation of cell death-related pathways, based on reduced p-JNK, Bax expression, tumor necrosis factor-α, caspase-9, and caspase-3 activity in the NAFLD model cells, and Bcl-2 expression was enhanced in the NAFLD model cells compared with the control group. These findings indicate that MMO have antioxidant and anti-apoptotic effects on NAFLD model cells and may thus exert protective effects against NAFLD. PMID:28216552

Radioprotective effect of orally administered beta-d-glucan derived from Saccharomyces cerevisiae.

PubMed

Liu, Fang; Wang, Zhuanzi; Liu, Jia; Li, Wenjian

2018-04-21

The present study was to evaluate the in vivo radioprotective effect of oral administration of Saccharomyces cerevisiae-derived-beta-d-glucan (S. cerevisiae-BG) and to investigate the protective mechanism. The results demonstrated that oral pretreatment with 350 mg/kg S. cerevisiae-BG once daily for 14 consecutive days significantly increased the survival rate of mice from 6 Gy X-rays irradiation. At the 30th day after irradiation, cellularity and the percentage of hematopoietic stem/progenitor cells in bone marrow (BM) of surviving mice were increased by S. cerevisiae-BG. Further studies showed that S. cerevisiae-BG decreased BM cell DNA damage and improved BM cell cycle progress in irradiated mice. And the reactive oxygen species (ROS) levels in BM cells of irradiated mice were also decreased by S. cerevisiae-BG. These results indicated that oral S. cerevisiae-BG exhibited obviously radioprotective effect in mice and the protective effect may be attributed to the polysaccharide's hematopoiesis-modulating action and free radical scavenging property. S. cerevisiae-BG protects BM cells from radiation damage through scavenging BM cell ROS, mitigating BM cell DNA damage and improving cell cycle progress, and thus mitigated myelosuppression induced by irradiation and stimulated hematopoiesis, ultimately increased the survival of radiated mice. Copyright © 2018. Published by Elsevier B.V.

Bacopa monnieri protects SH-SY5Y cells against tert-Butyl hydroperoxide-induced cell death via the ERK and PI3K pathways.

PubMed

Petcharat, Kanoktip; Singh, Meharvan; Ingkaninan, Kornkanok; Attarat, Jongrak; Yasothornsrikul, Sukkid

2015-01-01

Oxidative stress plays an important role in the pathological processes of various neurodegenerative diseases. Bacopa monnieri (BM) has a potent antioxidant property. Therefore, the purpose of this study was to evaluate the neuroprotective potential of BM against SH-SY5Y neuroblastoma cell death induced by the pro-oxidant insult, tert -Butyl hydroperoxide (TBHP), and to identify possible mechanisms related to its neuroprotective action. The neuroprotective effect of BM was evaluated by the degree of protection against TBHP-induced cell death in human SH-SY5Y cells that was measured by calcein-AM assay. ERK1/2 and Akt phosphorylation was evaluated by immunoblotting. We found that BM exhibited protection against TBHP-mediated cytotoxicity. The neuroprotective effect of BM was abolished in the presence of either ERK1/2 or PI3K inhibitors. In addition, western blotting with anti-phospho-ERK1/2 and anti-phospho-Akt antibodies showed that BM increased both ERK1/2 and Akt phosphorylation. These results suggest that BM by activation of ERK/MAPK and PI3K/Akt signaling pathways protects SH-SY5Y cells from TBHP-induced cell death.

Identification of ion-channel modulators that protect against aminoglycoside-induced hair cell death

PubMed Central

Kenyon, Emma J.; Kirkwood, Nerissa K.; Kitcher, Siân R.; O’Reilly, Molly; Cantillon, Daire M.; Goodyear, Richard J.; Secker, Abigail; Baxendale, Sarah; Bull, James C.; Waddell, Simon J.; Whitfield, Tanya T.; Ward, Simon E.; Kros, Corné J.; Richardson, Guy P.

2017-01-01

Aminoglycoside antibiotics are used to treat life-threatening bacterial infections but can cause deafness due to hair cell death in the inner ear. Compounds have been described that protect zebrafish lateral line hair cells from aminoglycosides, but few are effective in the cochlea. As the aminoglycosides interact with several ion channels, including the mechanoelectrical transducer (MET) channels by which they can enter hair cells, we screened 160 ion-channel modulators, seeking compounds that protect cochlear outer hair cells (OHCs) from aminoglycoside-induced death in vitro. Using zebrafish, 72 compounds were identified that either reduced loading of the MET-channel blocker FM 1-43FX, decreased Texas red–conjugated neomycin labeling, or reduced neomycin-induced hair cell death. After testing these 72 compounds, and 6 structurally similar compounds that failed in zebrafish, 13 were found that protected against gentamicin-induced death of OHCs in mouse cochlear cultures, 6 of which are permeant blockers of the hair cell MET channel. None of these compounds abrogated aminoglycoside antibacterial efficacy. By selecting those without adverse effects at high concentrations, 5 emerged as leads for developing pharmaceutical otoprotectants to alleviate an increasing clinical problem. PMID:29263311

Identification of ion-channel modulators that protect against aminoglycoside-induced hair cell death.

PubMed

Kenyon, Emma J; Kirkwood, Nerissa K; Kitcher, Siân R; O'Reilly, Molly; Derudas, Marco; Cantillon, Daire M; Goodyear, Richard J; Secker, Abigail; Baxendale, Sarah; Bull, James C; Waddell, Simon J; Whitfield, Tanya T; Ward, Simon E; Kros, Corné J; Richardson, Guy P

2017-12-21

Aminoglycoside antibiotics are used to treat life-threatening bacterial infections but can cause deafness due to hair cell death in the inner ear. Compounds have been described that protect zebrafish lateral line hair cells from aminoglycosides, but few are effective in the cochlea. As the aminoglycosides interact with several ion channels, including the mechanoelectrical transducer (MET) channels by which they can enter hair cells, we screened 160 ion-channel modulators, seeking compounds that protect cochlear outer hair cells (OHCs) from aminoglycoside-induced death in vitro. Using zebrafish, 72 compounds were identified that either reduced loading of the MET-channel blocker FM 1-43FX, decreased Texas red-conjugated neomycin labeling, or reduced neomycin-induced hair cell death. After testing these 72 compounds, and 6 structurally similar compounds that failed in zebrafish, 13 were found that protected against gentamicin-induced death of OHCs in mouse cochlear cultures, 6 of which are permeant blockers of the hair cell MET channel. None of these compounds abrogated aminoglycoside antibacterial efficacy. By selecting those without adverse effects at high concentrations, 5 emerged as leads for developing pharmaceutical otoprotectants to alleviate an increasing clinical problem.

Effect of Drying Methods on Protein and DNA Conformation Changes in Lactobacillus rhamnosus GG Cells by Fourier Transform Infrared Spectroscopy.

PubMed

Hlaing, Mya M; Wood, Bayden R; McNaughton, Don; Ying, DanYang; Dumsday, Geoff; Augustin, Mary Ann

2017-03-01

Microencapsulation protects cells against environmental stress encountered during the production of probiotics, which are used as live microbial food ingredients. Freeze-drying and spray-drying are used in the preparation of powdered microencapsulated probiotics. This study examines the ability of Fourier transform infrared (FTIR) spectroscopy to detect differences in cells exposed to freeze-drying and spray-drying of encapsulated Lactobacillus rhamnosus GG cells. The FTIR analysis clearly demonstrated there were more significant molecular changes in lipid, fatty acid content, protein, and DNA conformation of nonencapsulated compared to encapsulated bacterial cells. The technique was also able to differentiate between spray-dried and freeze-dried cells. The results also revealed the extent of protection from a protein-carbohydrate-based encapsulant matrix on the cells depending on the type drying process. The extent of this protection to the dehydration stress was shown to be less in spray-dried cells than in freeze-dried cells. This suggests that FTIR could be used as a rapid, noninvasive, and real-time measurement technique to detect detrimental drying effects on cells.

Edaravone Protects against Methylglyoxal-Induced Barrier Damage in Human Brain Endothelial Cells

PubMed Central

Tóth, Andrea E.; Walter, Fruzsina R.; Bocsik, Alexandra; Sántha, Petra; Veszelka, Szilvia; Nagy, Lajos; Puskás, László G.; Couraud, Pierre-Olivier; Takata, Fuyuko; Dohgu, Shinya; Kataoka, Yasufumi; Deli, Mária A.

2014-01-01

Background Elevated level of reactive carbonyl species, such as methylglyoxal, triggers carbonyl stress and activates a series of inflammatory responses leading to accelerated vascular damage. Edaravone is the active substance of a Japanese medicine, which aids neurological recovery following acute brain ischemia and subsequent cerebral infarction. Our aim was to test whether edaravone can exert a protective effect on the barrier properties of human brain endothelial cells (hCMEC/D3 cell line) treated with methylglyoxal. Methodology Cell viability was monitored in real-time by impedance-based cell electronic sensing. The barrier function of the monolayer was characterized by measurement of resistance and flux of permeability markers, and visualized by immunohistochemistry for claudin-5 and β-catenin. Cell morphology was also examined by holographic phase imaging. Principal Findings Methylglyoxal exerted a time- and dose-dependent toxicity on cultured human brain endothelial cells: a concentration of 600 µM resulted in about 50% toxicity, significantly reduced the integrity and increased the permeability of the barrier. The cell morphology also changed dramatically: the area of cells decreased, their optical height significantly increased. Edaravone (3 mM) provided a complete protection against the toxic effect of methylglyoxal. Co-administration of edaravone restored cell viability, barrier integrity and functions of brain endothelial cells. Similar protection was obtained by the well-known antiglycating molecule, aminoguanidine, our reference compound. Conclusion These results indicate for the first time that edaravone is protective in carbonyl stress induced barrier damage. Our data may contribute to the development of compounds to treat brain endothelial dysfunction in carbonyl stress related diseases. PMID:25033388

Nitric oxide protects murine embryonic liver cells (BNL CL.2) from cytotoxicity induced by glucose deprivation.

PubMed

Pae, H O; Kim, H G; Paik, Y S; Paik, S G; Kim, Y M; Oh, G S; Chung, H T

2000-03-01

We investigated the protective effects of nitric oxide on cell death of murine embryonic liver cells (BNL CL.2) after glucose deprivation. Endogenous nitric oxide production by BNL CL.2 cells was induced by 6 hr pretreatment with interferon-gamma and lipopolysaccharide. We used sodium nitroprusside and S-nitroso-L-glutathione as exogenous nitric oxide-generating compounds. All agents were used at doses that did not show direct cytotoxicity as measured by crystal violet staining assay. In the BNL CL.2 cells, the viability dropped very steeply after 24 hr incubation with glucose-free media. Endogenous nitric oxide produced by treatment of the cells with interferon-gamma and lipopolysaccharide protected the cells from glucose deprivation-induced cytotoxicity, but did not protect them in the presence of the nitric oxide synthesis inhibitor, N(G)-monomethyl-L-arginine. Exogenous nitric oxide protected the cells from glucose deprivation-induced cytotoxicity in a concentration-dependent manner. Cytoprotection by nitric oxide donors was abolished by the use of nitric oxide scavenger, 2-phenyl-4,4,5,5,-tetramethylimidazole, but not by the soluble guanosine cyclase inhibitor, 1H-[1,2,4]oxadiazole[4,3-a]quinoxalin-1-one. In addition, cytoprotective effects comparable to endogenous or exogenous nitric oxide were not observed when the cells were incubated with dibutyl guanosine 3',5'-cyclic monophosphate. Based upon these results, we suggest that nitric oxide may enhance the cell survival of BNL CL.2 cells after glucose deprivation via a guanosine 3',5'-cyclic monophosphate-independent pathway.

Lead toxicity induces autophagy to protect against cell death through mTORC1 pathway in cardiofibroblasts

PubMed Central

Sui, Li; Zhang, Rui-Hong; Zhang, Ping; Yun, Ke-Li; Zhang, Hong-Cai; Liu, Li; Hu, Ming-Xu

2015-01-01

Heavy metals, such as lead (Pb2+), are usually accumulated in human bodies and impair human's health. Lead is a metal with many recognized adverse health side effects and yet the molecular processes underlying lead toxicity are still poorly understood. In the present study, we proposed to investigate the effects of lead toxicity in cultured cardiofibroblasts. After lead treatment, cultured cardiofibroblasts showed severe endoplasmic reticulum (ER) stress. However, the lead-treated cardiofibroblasts were not dramatically apoptotic. Further, we found that these cells determined to undergo autophagy through inhibiting mammalian target of rapamycin complex 1 (mTORC1) pathway. Moreover, inhibition of autophagy by 3-methyladenine (3-MA) may dramatically enhance lead toxicity in cardiofibroblasts and cause cell death. Our data establish that lead toxicity induces cell stress in cardiofibroblasts and protective autophagy is activated by inhibition of mTORC1 pathway. These findings describe a mechanism by which lead toxicity may promote the autophagy of cardiofibroblasts cells, which protects cells from cell stress. Our findings provide evidence that autophagy may help cells to survive under ER stress conditions in cardiofibroblasts and may set up an effective therapeutic strategy for heavy metal toxicity. PMID:25686247

Lead toxicity induces autophagy to protect against cell death through mTORC1 pathway in cardiofibroblasts.

PubMed

Sui, Li; Zhang, Rui-Hong; Zhang, Ping; Yun, Ke-Li; Zhang, Hong-Cai; Liu, Li; Hu, Ming-Xu

2015-03-31

Heavy metals, such as lead (Pb(2+)), are usually accumulated in human bodies and impair human's health. Lead is a metal with many recognized adverse health side effects and yet the molecular processes underlying lead toxicity are still poorly understood. In the present study, we proposed to investigate the effects of lead toxicity in cultured cardiofibroblasts. After lead treatment, cultured cardiofibroblasts showed severe endoplasmic reticulum (ER) stress. However, the lead-treated cardiofibroblasts were not dramatically apoptotic. Further, we found that these cells determined to undergo autophagy through inhibiting mammalian target of rapamycin complex 1 (mTORC1) pathway. Moreover, inhibition of autophagy by 3-methyladenine (3-MA) may dramatically enhance lead toxicity in cardiofibroblasts and cause cell death. Our data establish that lead toxicity induces cell stress in cardiofibroblasts and protective autophagy is activated by inhibition of mTORC1 pathway. These findings describe a mechanism by which lead toxicity may promote the autophagy of cardiofibroblasts cells, which protects cells from cell stress. Our findings provide evidence that autophagy may help cells to survive under ER stress conditions in cardiofibroblasts and may set up an effective therapeutic strategy for heavy metal toxicity.

Protective effects of sulphonated formononetin in a rat model of cerebral ischemia and reperfusion injury.

PubMed

Zhu, Haibo; Zou, Libo; Tian, Jingwei; Lin, Fei; He, Jie; Hou, Jian

2014-03-01

Sodium formononetin-3'-sulphonate is a derivative of the plant isoflavone formononetin. The present study aimed to investigate the neuroprotective and angiogenesis effects of sodium formononetin-3'-sulphonate in vivo and in vitro. Treatment with sodium formononetin-3'-sulphonate (3, 7.5, 15, and 30 mg/kg, intravenous injection) could protect the brain from ischemia and reperfusion injury by improving neurological function, suppressing cell apoptosis, and increasing expression levels of vascular endothelial growth factor and platelet endothelial cell adhesion molecule 1 by middle cerebral artery occlusion. Treatment with sodium formononetin-3'-sulphonate (10 and 20 µg/mL) significantly increased cell migration, tube formation, and vascular endothelial growth factor and platelet endothelial cell adhesion molecule levels in human umbilical vein endothelial cells. Our results suggest that sodium formononetin-3'-sulphonate provides significant neuroprotective effects against cerebral ischemia and reperfusion injury in rats, and improves cerebrovascular angiogenesis in human umbilical vein endothelial cells. The protective mechanisms of sodium formononetin-3'-sulphonate may be attributed to the suppression of cell apoptosis and improved cerebrovascular angiogenesis by promoting vascular endothelial growth factor and platelet endothelial cell adhesion molecule expression. Georg Thieme Verlag KG Stuttgart · New York.

Baicalin Protects against TNF-α-Induced Injury by Down-Regulating miR-191a That Targets the Tight Junction Protein ZO-1 in IEC-6 Cells.

PubMed

Wang, Li; Zhang, Ren; Chen, Jian; Wu, Qihui; Kuang, Zaoyuan

2017-04-01

Tumor necrosis factor-alpha (TNF-α) plays an important role in the developing process of inflammatory bowel disease. Tight junction protein zonula occludens-1 (ZO-1), one of epithelial junctional proteins, maintains the permeability of intestinal barrier. The objective of this study was to investigate the mechanism of the protective effect of baicalin on TNF-α-induced injury and ZO-1 expression in intestinal epithelial cells (IECs). We found that baicalin pretreatment significantly improved cell viability and cell migration following TNF-α stimulation. miR-191a inhibitor increased the protective effect of baicalin on cell motility injured by TNF-α. In addition, miR-191a down-regulated the mRNA and protein level of its target gene ZO-1. TNF-α stimulation increased miR-191a expression, leading to the decline of ZO-1 mRNA and protein. Moreover, pretreatment with baicalin reversed TNF-α induced decrease of ZO-1 and increase of miR-191a, miR-191a inhibitor significantly enhanced ZO-1 protein expression restored by baicalin. These results indicate that baicalin exerts a protective effect on IEC-6 (rat small intestinal epithelial cells) cells against TNF-α-induced injury, which is at least partly via inhibiting the expression of miR-191a, thus increasing ZO-1 mRNA and protein levels.

Photooxidative damage in retinal pigment epithelial cells via GRP78 and the protective role of grape skin polyphenols.

PubMed

Zhao, Zhao; Sun, Tao; Jiang, Yun; Wu, Lijiang; Cai, Xiangzhong; Sun, Xiaodong; Sun, Xiangjun

2014-12-01

Blue light induced oxidative damage and ER stress are related to the pathogenesis of age-related macular degeneration (AMD). However, the mechanism of blue light-induced damage remained obscure. The objective of this work is to assess the photooxidative damage to retinal pigment epithelial cells (RPE) and oxidation-induced changes in expression of ER stress associated apoptotic proteins, and investigate the mechanism underlying the protective effects of grape skin extracts. To mimic lipofuscin-mediated photooxidation in vivo, ARPE-19 cells that accumulated A2E, one of lipofuscin fluorophores, were used as a model system to investigate the mechanism of photooxidative damage and the protective effects of grape skin polyphenols. Exposure of A2E containing ARPE-19 cells to blue light resulted in significant apoptosis and increases in levels of GRP78, CHOP, p-JNK, Bax, cleaved caspase-9, and cleaved caspase-3, indicating that photooxidative damage to RPE cells is mediated by the ER-stress-induced intrinsic apoptotic pathway. Cells in which GRP78 had been knocked down with shRNA were more vulnerable to photooxidative damage. Pre-treatment of blue-light-exposed A2E containing ARPE-19 cells, with grape skin extracts, inhibited apoptosis, in a dose dependent manner. Knockdown GRP78 blocked the protective effect of grape skin extracts.

Protective effects of N-acetylcysteine against monosodium glutamate-induced astrocytic cell death.

PubMed

Park, Euteum; Yu, Kyoung Hwan; Kim, Do Kyung; Kim, Seung; Sapkota, Kumar; Kim, Sung-Jun; Kim, Chun Sung; Chun, Hong Sung

2014-05-01

Monosodium glutamate (MSG) is a flavor enhancer, largely used in the food industry and it was reported to have excitotoxic effects. Higher amounts of MSG consumption have been related with increased risk of many diseases, including Chinese restaurant syndrome and metabolic syndromes in human. This study investigated the protective effects of N-acetylcysteine (NAC) on MSG-induced cytotoxicity in C6 astrocytic cells. MSG (20 mM)-induced reactive oxygen species (ROS) generation and apoptotic cell death were significantly attenuated by NAC (500 μM) pretreatment. NAC effectively inhibited the MSG-induced mitochondrial membrane potential (MMP) loss and intracellular reduced glutathione (GSH) depletion. In addition, NAC significantly attenuated MSG-induced endoplasmic reticulum (ER) stress markers, such as XBP1 splicing and CHOP, PERK, and GRP78 up-regulation. Furthermore, NAC prevented the changes of MSG-induced Bcl-2 expression level. These results suggest that NAC can protect C6 astrocytic cells against MSG-induced oxidative stress, mitochondrial dysfunction, and ER stress. Copyright © 2014 Elsevier Ltd. All rights reserved.

Carvedilol protects bone marrow stem cells against hydrogen peroxide-induced cell death via PI3K-AKT pathway.

PubMed

Chen, Meihui; Chen, Shudong; Lin, Dingkun

2016-03-01

Carvedilol, a nonselective β-adrenergic receptor blocker, has been reported to exert potent anti-oxidative activities. In the present study, we aimed to investigate the effects of carvedilol against hydrogen peroxide (H2O2)-induced bone marrow-derived mesenchymal stem cells (BMSCs) death, which imitate the microenvironment surrounding transplanted cells in the injured spinal cord in vitro. Carvedilol significantly reduced H2O2-induced reactive oxygen species production, apoptosis and subsequent cell death. LY294002, the PI3K inhibitor, blocked the protective effects and up-regulation of Akt phosphorylation of carvedilol. Together, our results showed that carvedilol protects H2O2-induced BMSCs cell death partly through PI3K-Akt pathway, suggesting carvedilol could be used in combination with BMSCs for the treatment of spinal cord injury by improving the cell survival and oxidative stress microenvironments. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Hepatocyte Growth Factor Is Required for Mesenchymal Stromal Cell Protection Against Bleomycin-Induced Pulmonary Fibrosis

PubMed Central

Cahill, Emer F.; Kennelly, Helen; Carty, Fiona; Mahon, Bernard P.

2016-01-01

The incidence of idiopathic pulmonary fibrosis is on the rise and existing treatments have failed to halt or reverse disease progression. Mesenchymal stromal cells (MSCs) have potent cytoprotective effects, can promote tissue repair, and have demonstrated efficacy in a range of fibrotic lung diseases; however, the exact mechanisms of action remain to be elucidated. Chemical antagonists and short hairpin RNA knockdown were used to identify the mechanisms of action used by MSCs in promoting wound healing, proliferation, and inhibiting apoptosis. Using the bleomycin induced fibrosis model, the protective effects of early or late MSC administration were examined. The role for hepatocyte growth factor (HGF) in MSC protection against bleomycin lung injury was examined using HGF knockdown MSC. Terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling assay was performed on ex vivo lung sections to examine the effects of MSC on apoptosis. MSC conditioned media (CM) enhanced wound closure and inhibited apoptosis of pulmonary cells in vitro. HGF was required for MSC CM enhancement of epithelial cell proliferation and inhibition of apoptosis. In contrast, MSC required COX-2 for CM to inhibit fibroblast proliferation. In a murine model, early administration of MSC protected against bleomycin induced lung fibrosis and correlated with reduced levels of the proinflammatory cytokine interleukin-1β, reduced levels of apoptosis, and significantly increased levels of HGF. These protective effects were in part mediated by MSC derived HGF as HGF knockdown MSC were unable to protect against fibrosis in vivo. These findings delineate the mechanisms of MSC protection in a preclinical model of fibrotic lung disease. Significance The mechanisms used by mesenchymal stromal cells (MSCs) in mediating protective effects in chronic models of lung disease are not understood and remain to be elucidated. These findings from in vitro studies highlight an important role for the MSC-derived soluble factors hepatocyte growth factor (HGF) and prostaglandin E2 in promoting wound healing and inhibiting apoptosis. Furthermore, this study translates these findings demonstrating an important role for HGF in the protective effects mediated by MSC in vivo in the bleomycin model. These findings support a targeted approach to enhancing MSC therapy for fibrotic disease and highlight the importance of timing of MSC therapy. PMID:27388243

A crucial role for plasmacytoid dendritic cells in antiviral protection by CpG ODN–based vaginal microbicide

PubMed Central

Shen, Hong; Iwasaki, Akiko

2006-01-01

Topical microbicides represent a promising new approach to preventing HIV and other sexually transmitted infections. TLR agonists are ideal candidates for microbicides, as they trigger a multitude of antiviral genes effective against a broad range of viruses. Although vaginal application of CpG oligodeoxynucleotides (ODNs) and poly I:C has been shown to protect mice from genital herpes infection, the mechanism by which these agents provide protection remains unclear. Here, we show that plasmacytoid DCs (pDCs) are required for CpG ODN–mediated protection against lethal vaginal challenge with herpes simplex virus type 2 (HSV-2). Moreover, we demonstrate that cells of both the hematopoietic and stromal compartments must respond to CpG ODN via TLR9 and to type I IFNs through IFN-αβ receptor (IFN-αβR) for protection. Thus, crosstalk between pDCs and vaginal stromal cells provides for optimal microbicide efficacy. Our results imply that temporally and spatially controlled targeting of CpG ODN to pDCs and epithelial cells can potentially maximize their effectiveness as microbicides while minimizing the associated inflammatory responses. PMID:16878177

Erythropoietin as a novel brain and kidney protective agent.

PubMed

Moore, E M; Bellomo, R; Nichol, A D

2011-05-01

Erythropoietin is a 30.4 kDa glycoprotein produced by the kidney, which is mostly known for its physiological function in regulating red blood cell production in the bone marrow Accumulating evidence, however suggests that erythropoietin has additional organ protective effects, which may specifically be useful in protecting the brain and kidneys from injury. Experimental evidence suggests that these protective mechanisms are multi-factorial in nature and may include inhibition of apoptotic cell death, stimulation of cellular regeneration, inhibition of deleterious pathways and promotion of recovery. In this article we review the physiology of erythropoietin, assess previous work that supports the role of erythropoietin as a general tissue protective agent and explain the mechanisms by which it may achieve this tissue protective effect. We then focus on specific laboratory and clinical data that suggest that erythropoietin has a strong brain protective and kidney protective effect. In addition, we comment on the implications of these studies for clinicians at the bedside and for researchers designing controlled trials to further elucidate the true clinical utility of erythropoietin as a neuroprotective and nephroprotective agent. Finally, we describe EPO-TBI, a double-blinded multi-centre randomised controlled trial involving the authors that is being conducted to investigate the organ protective effects of erythropoietin on the brain, and also assesses its effect on the kidneys.

Protective Role of Hsp27 Protein Against Gamma Radiation-Induced Apoptosis and Radiosensitization Effects of Hsp27 Gene Silencing in Different Human Tumor Cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aloy, Marie-Therese; Hospices Civils de Lyon, Service de Radiotherapie, Centre Hospitalier Lyon-Sud, Pierre-Benite; Hadchity, Elie

Purpose: The ability of heat shock protein 27 (Hsp27) to protect cells from stressful stimuli and its increased levels in tumors resistant to anticancer therapeutics suggest that it may represent a target for sensitization to radiotherapy. In this study, we investigate the protective role of Hsp27 against radiation-induced apoptosis and the effect of its attenuation in highly expressing radioresistant cancer cell lines. Methods and Materials: We examined clonogenic death and the kinetics of apoptotic events in different tumor cell lines overexpressing or underexpressing Hsp27 protein irradiated with photons. The radiosensitive Jurkat cell line, which does not express Hsp27 constitutively ormore » in response to {gamma}-rays, was stably transfected with Hsp27 complementary DNA. Attenuation of Hsp27 expression was accomplished by antisense or RNAi (interfering RNA) strategies in SQ20B head-and-neck squamous carcinoma, PC3 prostate cancer, and U87 glioblastoma radioresistant cells. Results: We measured concentration-dependent protection against the cytotoxic effects of radiation in Jurkat-Hsp27 cells, which led to a 50% decrease in apoptotic cells at 48 hours in the highest expressing cells. Underlying mechanisms leading to radiation resistance involved a significant increase in glutathione levels associated with detoxification of reactive oxygen species, a delay in mitochondrial collapse, and caspase activation. Conversely, attenuation of Hsp27 in SQ20B cells, characterized by their resistance to apoptosis, sensitizes cells to irradiation. This was emphasized by increased apoptosis, decreased glutathione basal level, and clonogenic cell death. Sensitization to irradiation was confirmed in PC3 and U87 radioresistant cells. Conclusion: Hsp27 gene therapy offers a potential adjuvant to radiation-based therapy of resistant tumors.« less

Protective Effect of 2-Dodecyl-6-Methoxycyclohexa-2, 5-Diene-1, 4-Dione, Isolated from Averrhoa Carambola L., Against Palmitic Acid-Induced Inflammation and Apoptosis in Min6 Cells by Inhibiting the TLR4-MyD88-NF-κB Signaling Pathway.

PubMed

Xie, Qiuqiao; Zhang, Shijun; Chen, Chunxia; Li, Juman; Wei, Xiaojie; Xu, Xiaohui; Xuan, Feifei; Chen, Ning; Pham, Thithaihoa; Qin, Ni; He, Junhui; Ye, Fangxing; Huang, Wansu; Huang, Renbin; Wen, Qingwei

2016-01-01

Studies have demonstrated that 2-dodecyl-6-methoxycyclohexa-2, 5-diene-1, 4-dione (DMDD), isolated from the roots of Averrhoa carambola L., has significant therapeutic potential for the treatment of diabetes. However, the protective effect of DMDD against pancreatic beta cell dysfunction has never been reported. We investigated whether DMDD protected against palmitic acid-induced dysfunction in pancreatic β-cell line Min6 cells by attenuating the inflammatory response and apoptosis and to shed light on its possible mechanism. Cell viability was assessed by CCK-8. Glucose-stimulated insulin secretion levels and inflammatory cytokines levels were examined by ELISA. Apoptosis was assessed by Annexin V-FITC/PI Flow cytometry assay, Hoechst 33342/PI double-staining assay, and Transmission electron microscopy assay. Relative quantitative real-time PCR and western blot were used to determine the expressions of genes and proteins. Cell viability and glucose-stimulated insulin secretion levels were increased in DMDD-pretreated Min6 cells. DMDD inhibited inflammatory cytokines IL-6, TNF-α and MCP-1 generations in palmitic acid (PA)-induced Min6 cells. Moreover, DMDD protected against PA-induced Min6 cells apoptosis and the expression of Cleaved-Caspase-3, -8 and -9 were down-regulated and the Bcl-2/Bax ratio was increased in DMDD-pretreated Min6 cells. In addition, the expression of TLR4, MyD88 and NF-κB were down-regulated in DMDD-pretreated Min6 cells and TAK-242-pretreated group cells. DMDD protected Min6 cells against PA-induced dysfunction by attenuating the inflammatory response and apoptosis, and its mechanism of this protection was associated with inhibiting the TLR4-MyD88-NF-κB signaling pathway. © 2016 The Author(s) Published by S. Karger AG, Basel.

TolC plays a crucial role in immune protection conferred by Edwardsiella tarda whole-cell vaccines.

PubMed

Wang, Chao; Peng, Bo; Li, Hui; Peng, Xuan-Xian

2016-07-12

Although vaccines developed from live organisms have better efficacy than those developed from dead organisms, the mechanisms underlying this differential efficacy remain unexplored. In this study, we combined sub-immunoproteomics with immune challenge to investigate the action of the outer membrane proteome in the immune protection conferred by four Edwardsiella tarda whole-cell vaccines prepared via different treatments and to identify protective immunogens that play a key role in this immune protection. Thirteen spots representing five outer membrane proteins and one cytoplasmic protein were identified, and it was found that their abundance was altered in relation with the immune protective abilities of the four vaccines. Among these proteins, TolC and OmpA were found to be the key immunogens conferring the first and second highest degrees of protection, respectively. TolC was detected in the two effective vaccines (live and inactivated-30-F). The total antiserum and anti-OmpA titers were higher for the two effective vaccines than for the two ineffective vaccines (inactivated-80-F and inactivated-100). Further evidence demonstrated that the live and inactivated-30-F vaccines demonstrated stronger abilities to induce CD8+ and CD4+ T cell differentiation than the other two evaluated vaccines. Our results indicate that the outer membrane proteome changes dramatically following different treatments, which contributes to the effectiveness of whole-cell vaccines.

Coniferyl Aldehyde Reduces Radiation Damage Through Increased Protein Stability of Heat Shock Transcriptional Factor 1 by Phosphorylation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Seo-Young; Lee, Hae-June; Nam, Joo-Won

Purpose: We previously screened natural compounds and found that coniferyl aldehyde (CA) was identified as an inducer of HSF1. In this study, we further examined the protective effects of CA against ionizing radiation (IR) in normal cell system. Methods and Materials: Western blotting and reverse transcription-polymerase chain reaction tests were performed to evaluate expression of HSF1, HSP27, and HSP70 in response to CA. Cell death and cleavage of PARP and caspase-3 were analyzed to determine the protective effects of CA in the presence of IR or taxol. The protective effects of CA were also evaluated using animal models. Results: CAmore » increased stability of the HSF1 protein by phosphorylation at Ser326, which was accompanied by increased expression of HSP27 and HSP70. HSF1 phosphorylation at Ser326 by CA was mediated by EKR1/2 activation. Cotreatment of CA with IR or taxol in normal cells induced protective effects with phosphorylation- dependent patterns at Ser326 of HSF1. The decrease in bone marrow (BM) cellularity and increase of terminal deoxynucleotidyl transferase dUTP nick end labeling–positive BM cells by IR were also significantly inhibited by CA in mice (30.6% and 56.0%, respectively). A549 lung orthotopic lung tumor model indicated that CA did not affect the IR-mediated reduction of lung tumor nodules, whereas CA protected normal lung tissues from the therapeutic irradiation. Conclusions: These results suggest that CA may be useful for inducing HSF1 to protect against normal cell damage after IR or chemotherapeutic agents.« less

Pigment developed to protect spacecraft/solar cells from Sun's harmful rays.

NASA Technical Reports Server (NTRS)

1995-01-01

A pigment (phthalocyanine) is studied at the Marshall Materials and Processes Lab. The pigment has the ability to protect spacecraft against the harmful effects of the Sun's ultraviolet rays, and to increase the efficiency and life of solar cells.

Mosaic H5 Hemagglutinin Provides Broad Humoral and Cellular Immune Responses against Influenza Viruses

PubMed Central

Kamlangdee, Attapon; Kingstad-Bakke, Brock

2016-01-01

ABSTRACT The most effective way to prevent influenza virus infection is via vaccination. However, the constant mutation of influenza viruses due to antigenic drift and shift compromises vaccine efficacy. This represents a major challenge to the development of a cross-protective vaccine that can protect against circulating viral antigenic diversity. Using the modified vaccinia Ankara (MVA) virus, we had previously generated a recombinant vaccine against highly pathogenic avian influenza virus (H5N1) based on an in silico mosaic approach. This MVA-H5M construct protected mice against multiple clades of H5N1 and H1N1 viruses. We have now further characterized the immune responses using immunodepletion of T cells and passive serum transfer, and these studies indicate that antibodies are the main contributors in homosubtypic protection (H5N1 clades). Compared to a MVA construct expressing hemagglutinin (HA) from influenza virus A/VN/1203/04 (MVA-HA), the MVA-H5M vaccine markedly increased and broadened B cell and T cell responses against H5N1 virus. The MVA-H5M also provided effective protection with no morbidity against H5N1 challenge, whereas MVA-HA-vaccinated mice showed clinical signs and experienced significant weight loss. In addition, MVA-H5M induced CD8+ T cell responses that play a major role in heterosubtypic protection (H1N1). Finally, expression of the H5M gene as either a DNA vaccine or a subunit protein protected mice against H5N1 challenge, indicating the effectiveness of the mosaic sequence without viral vectors for the development of a universal influenza vaccine. IMPORTANCE Influenza viruses infect up to one billion people around the globe each year and are responsible for 300,000 to 500,000 deaths annually. Vaccines are still the main intervention to prevent infection, but they fail to provide effective protection against heterologous strains of viruses. We developed broadly reactive H5N1 vaccine based on an in silico mosaic approach and previously demonstrated that modified vaccinia Ankara expressing an H5 mosaic hemagglutinin prevented infection with multiple clades of H5N1 and limited severe disease after H1N1 infection. Further characterization revealed that antibody responses and T cells are main contributors to protection against H5N1 and H1N1 viruses, respectively. The vaccine also broadens both T cell and B cell responses compared to native H5 vaccine from influenza virus A/Vietnam/1203/04. Finally, delivering the H5 mosaic as a DNA vaccine or as a purified protein demonstrated effective protection similar to the viral vector approach. PMID:27194759

Formononetin protects neurons against hypoxia-induced cytotoxicity through upregulation of ADAM10 and sAβPPα.

PubMed

Sun, Miao; Zhou, Ting; Zhou, Liang; Chen, Qiang; Yu, Yan; Yang, Huan; Zhong, Kaiyin; Zhang, Ximeng; Xu, Feng; Cai, Shaoqing; Yu, Albert; Zhang, Hui; Xiao, Ruizhong; Xiao, Dongsheng; Chui, Dehua

2012-01-01

Formononetin, an active constituent of the Chinese herb Astragali Radix, has been reported to have beneficial effects for Alzheimer's disease (AD). Yet the mechanism of this effect remains to be elucidated. The present study shows that formononetin increases soluble-AβPPα (sAβPPα) secretion and thus protects human-AβPP Swedish mutation cell (N2a-AβPP cell) from hypoxia-induced apoptosis. Using hypoxic N2a-AβPP cell as an in vitro model of AD-like pathology, we confirmed that regular treatment with formononetin could have neuroprotective effects, followed respectively by reduced caspase 3 activity and increased cell viability. Strikingly, our data revealed that the caspase 3-blocking effect of formononetin was largely mediated by stimulation of α-secretase cleavage of AβPP, and increasing the secretion of its soluble form, sAβPPα. Moreover, the protective effect of formononetin was totally inhibited by TAPI-2, an α-secretase complex inhibitor, suggesting the role of the sAβPPα pathway in the neuroprotective response to formononetin. We also found that the stimulative effect of formononetin on α-secretase activity was mainly conducted by upregulating ADAM10 expression at the transcriptional level. Altogether, our study provides novel insights into how formononetin mediates stimulation of the ADAM10-sAβPPα pathway and exerts a neuronal protective effect.

Type I collagen gel protects murine fibrosarcoma L929 cells from TNFα-induced cell death

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Hong-Ju; He, Wen-Qi; Chen, Ling

Murine fibrosarcoma L929 cells have been used to test efficacy of proinflammatory cytokine TNFα. In the present study, we reported on protective effect of type I collagen gel used as L929 cell culture. L929 cell grew and proliferated well on collagen gel. However, the L929 cells exhibited cobblestone-like morphology which was much different from the spread fusiform shape when cultured on conventional cell dishes as well as the cells tended to aggregate. On conventional cell culture dishes, the cells treated with TNFα became round in shape and eventually died in a necroptotic manner. The cells cultured on collagen gel, however,more » were completely unaffected. TNFα treatment was reported to induce autophagy in L929 cells on the plastic dish, and therefore we investigated the effect of collagen gel on induction of autophagy. The results indicated that autophagy induced by TNFα treatment was much reduced when the cells were cultured on collagen gel. In conclusion, type I collagen gel protected L929 cell from TNFα-induced cell death. - Highlights: • Collagen gel culture changed the morphology of L929 cells. • L929 cell cultured on collagen gel were resistant to TNFα-induced cell death. • Collagen gel culture inhibited TNFα-induced autophagy in L929 cells.« less

Assessment of Immune Isolation of Allogeneic Mouse Pancreatic Progenitor Cells by a Macroencapsulation Device

PubMed Central

Faleo, Gaetano; Lee, Karim; Nguyen, Vinh; Tang, Qizhi

2016-01-01

Background Embryonic-stem-cell (ESC)-derived islets hold the promise of providing a renewable source of tissue for the treatment of insulin-dependent diabetes. Encapsulation may allow ESC-derived islets to be transplanted without immunosuppression, thus enabling wider application of this therapy. Methods In this study, we investigated the immunogenicity of mouse pancreatic progenitor cells and efficacy of a new macroencapsulation device in protecting these cells against alloimmune and autoimmune responses in mouse models. Results Mouse pancreatic progenitor cells activated the indirect but not the direct pathway of alloimmune response and were promptly rejected in immune competent hosts. The new macroencapsulation device abolished T cell activation induced by allogeneic splenocytes and protected allogeneic MIN6 β cells and pancreatic progenitors from rejection even in pre-sensitized recipients. In addition, the device was effective in protecting MIN6 cells in spontaneously diabetic non-obese diabetic recipients against both alloimmune and recurring autoimmune responses. Conclusion Our results demonstrate that macroencapsulation can effectively prevent immune sensing and rejection of allogeneic pancreatic progenitor cells in fully sensitized and autoimmune hosts. PMID:26982952

Sampling alien species inside and outside protected areas: Does it matter?

NASA Astrophysics Data System (ADS)

Moustakas, Aristides; Voutsela, Anneta; Katsanevakis, Stelios

2018-06-01

Data of alien species presences are generally more readily available in protected than non-protected areas due to higher sampling efforts inside protected areas. Are the results and conclusions based on analyses of data collected in protected areas representative of wider non-protected regions? We address this question by analysing some recently published data of alien plants in Greece. Mixed effects models were used with alien species presences in 8.25 x 8.25 km cells as dependent variable and the percentage of protected area, as well as the agricultural and artificial land cover types richness (as indicators of human presence) as independent variables. In addition, the spatial cross-correlation between the percentage of protected area and alien species richness was examined across scales. Results indicated that the percentage of protected area per cell is a poor predictor of alien species richness. Spatial analysis indicated that cells with higher percentage of protected areas have slightly less alien species than cells with lower percentage of protected areas. This result is likely to be driven by the overall negative correlation between habitat protection and anthropogenic activities. Thus, the conclusions deduced by data deriving from protected areas are likely to hold true for patterns of alien species in non-protected areas when the human pressures are accounted for.

Cocoa flavonoids protect hepatic cells against high-glucose-induced oxidative stress: relevance of MAPKs.

PubMed

Cordero-Herrera, Isabel; Martín, María Angeles; Goya, Luis; Ramos, Sonia

2015-04-01

Oxidative stress plays a main role in the pathogenesis of type 2 diabetes mellitus. Cocoa and (-)-epicatechin (EC), a main cocoa flavanol, have been suggested to exert beneficial effects in type 2 diabetes mellitus because of their protective effects against oxidative stress and insulin-like properties. In this study, the protective effect of EC and a cocoa phenolic extract (CPE) against oxidative stress induced by a high-glucose challenge, which causes insulin resistance, was investigated on hepatic HepG2 cells. Oxidative status, phosphorylated mitogen-activated protein kinases (MAPKs), nuclear factor E2 related factor 2 (Nrf2) and p-(Ser)-IRS-1 expression, and glucose uptake were evaluated. EC and CPE regulated antioxidant enzymes and activated extracellular-regulated kinase and Nrf2. EC and CPE pre-treatment prevented high-glucose-induced antioxidant defences and p-MAPKs, and maintained Nrf2 stimulation. The presence of selective MAPK inhibitors induced changes in redox status, glucose uptake, p-(Ser)- and total IRS-1 levels that were observed in CPE-mediated protection. EC and CPE recovered redox status of insulin-resistant HepG2 cells, suggesting that the functionality in EC- and CPE-treated cells was protected against high-glucose-induced oxidative insult. CPE beneficial effects on redox balance and insulin resistance were mediated by targeting MAPKs. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Morphine protects SH-SY5Y human neuroblastoma cells against 6-hydroxydopamine-induced cell damage: involvement of anti-oxidant, calcium blocking, and anti-apoptotic properties.

PubMed

Elyasi, Leila; Eftekhar-Vaghefi, Seyed Hassan; Esmaeili-Mahani, Saeed

2014-06-01

Parkinson's disease is a neurodegenerative disorder characterized by progressive and selective death of dopaminergic neurons. Understanding the neuroprotective effects of chemical reagents has attracted increasing attention. The μ opioid agonist morphine exerts both toxic and protective effects. However, until recently, the neuroprotective role of morphine against 6-hydroxydopamine (6-OHDA)-induced cell death has not been studied. Here, we investigated the effects of morphine on 6-OHDA-induced neurotoxicity in human neuroblastoma SH-SY5Y cell line as an in vitro model of Parkinson's disease. Cell damage was induced by 150 μM 6-OHDA, and the cells' viability was examined by MTT assay. Intracellular calcium, reactive oxygen species (ROS), and mitochondrial membrane potential were determined by the fluorescence spectrophotometry method. Fragmented DNA and biochemical markers of apoptosis were also determined by gel electrophoresis and immunoblotting, respectively. The data showed that 6-OHDA caused a loss of cell viability and mitochondrial membrane potential. In addition, intracellular ROS and calcium levels, activated caspase-3, Bax:Bcl-2 ratio, cytochrome c release, as well as DNA fragmentation were significantly increased in 6-OHDA-treated cells. Incubation of SH-SY5Y cells with morphine (100 μM) elicited a protective effect and reduced biochemical markers of cell damage and death. These results suggest that morphine has neuroprotective effects against 6-OHDA-induced neurotoxicity, and such effects are accompanied by its anti-oxidant, calcium blocking, and anti-apoptotic properties.

Intranasal Introduction of Fc-Fused Interleukin-7 Provides Long-Lasting Prophylaxis against Lethal Influenza Virus Infection.

PubMed

Kang, Moon Cheol; Choi, Dong-Hoon; Choi, Young Woo; Park, Seong Jeong; Namkoong, Hong; Park, Ki Seok; Ahn, So-Shin; Surh, Charles D; Yoon, Sun-Woo; Kim, Doo-Jin; Choi, Jung-ah; Park, Yunji; Sung, Young Chul; Lee, Seung-Woo

2015-12-09

Influenza A virus (IAV) infection frequently causes hospitalization and mortality due to severe immunopathology. Annual vaccination and antiviral drugs are the current countermeasures against IAV infection, but they have a limited efficacy against new IAV variants. Here, we show that intranasal pretreatment with Fc-fused interleukin-7 (IL-7-mFc) protects mice from lethal IAV infections. The protective activity of IL-7-mFc relies on transcytosis via neonatal Fc receptor (FcRn) in the lung and lasts for several weeks. Introduction of IL-7-mFc alters pulmonary immune environments, leading to recruitment of T cells from circulation and their subsequent residency as tissue-resident memory-like T (TRM-like) cells. IL-7-mFc-primed pulmonary TRM-like cells contribute to protection upon IAV infection by dual modes. First, TRM-like cells, although not antigen specific but polyclonal, attenuate viral replication at the early phase of IAV infection. Second, TRM-like cells augment expansion of IAV-specific cytotoxic T lymphocytes (CTLs), in particular at the late phase of infection, which directly control viruses. Thus, accelerated viral clearance facilitated by pulmonary T cells, which are either antigen specific or not, alleviates immunopathology in the lung and mortality from IAV infection. Depleting a subset of pulmonary T cells indicates that both CD4 and CD8 T cells contribute to protection from IAV, although IL-7-primed CD4 T cells have a more prominent role. Collectively, we propose intranasal IL-7-mFc pretreatment as an effective means for generating protective immunity against IAV infections, which could be applied to a potential prophylaxis for influenza pandemics in the future. The major consequence of a highly pathogenic IAV infection is severe pulmonary inflammation, which can result in organ failure and death at worst. Although vaccines for seasonal IAVs are effective, frequent variation of surface viral proteins hampers development of protective immunity. In this study, we demonstrated that intranasal IL-7-mFc pretreatment protected immunologically naive mice from lethal IAV infections. Intranasal pretreatment with IL-7-mFc induced an infiltration of T cells in the lung, which reside as effector/memory T cells with lung-retentive markers. Those IL-7-primed pulmonary T cells contributed to development of protective immunity upon IAV infection, reducing pulmonary immunopathology while increasing IAV-specific cytotoxic T lymphocytes. Since a single treatment with IL-7-mFc was effective in the protection against multiple strains of IAV for an extended period of time, our findings suggest a possibility that IL-7-mFc treatment, as a potential prophylaxis, can be developed for controlling highly pathogenic IAV infections. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Protection by the flavonoids quercetin and luteolin against peroxide- or menadione-induced oxidative stress in MC3T3-E1 osteoblast cells.

PubMed

Fatokun, Amos A; Tome, Mercedes; Smith, Robert A; Darlington, L Gail; Stone, Trevor W

2015-01-01

Potential protective effects of the flavonoids quercetin and luteolin have been examined against the oxidative stress of MC3T3-E1 osteoblast-like cells. Although hydrogen peroxide and menadione reduced cell viability, the toxicity was prevented by desferrioxamine or catalase but not superoxide dismutase, suggesting the involvement of hydrogen peroxide in both cases. Quercetin and luteolin reduced the oxidative damage, especially that caused by hydrogen peroxide. When cultures were pre-incubated with quercetin or luteolin, protection was reduced or lost. Protection was also reduced when a 24 h pre-incubation with the flavonoids was followed by exposure to menadione alone. Pretreating cultures with luteolin impaired protection by quercetin, whereas quercetin pretreatment did not affect protection by luteolin. It is concluded that quercetin and luteolin suppress oxidative damage to MC3T3-E1 cells, especially caused by peroxide. The reduction in protection by pretreatment implies a down-regulation of part of the toxic transduction pathway.

Neutrophils Are Central to Antibody-Mediated Protection against Genital Chlamydia.

PubMed

Naglak, Elizabeth K; Morrison, Sandra G; Morrison, Richard P

2017-10-01

Determining the effector populations involved in humoral protection against genital chlamydia infection is crucial to development of an effective chlamydial vaccine. Antibody has been implicated in protection studies in multiple animal models, and we previously showed that the passive transfer of immune serum alone does not confer immunity in the mouse. Using the Chlamydia muridarum model of genital infection, we demonstrate a protective role for both Chlamydia -specific immunoglobulin G (IgG) and polymorphonuclear neutrophils and show the importance of an antibody/effector cell interaction in mediating humoral immunity. While neutrophils were found to contribute significantly to antibody-mediated protection in vivo , natural killer (NK) cells were dispensable for protective immunity. Furthermore, gamma interferon (IFN-γ)-stimulated primary peritoneal neutrophils (PPNs) killed chlamydiae in vitro in an antibody-dependent manner. The results from this study support the view that an IFN-γ-activated effector cell population cooperates with antibody to protect against genital chlamydia and establish neutrophils as a key effector cell in this response. Copyright © 2017 Naglak et al.

Protective effect of acetyl-L-carnitine on propofol-induced toxicity in embryonic neural stem cells.

PubMed

Liu, Fang; Rainosek, Shuo W; Sadovova, Natalya; Fogle, Charles M; Patterson, Tucker A; Hanig, Joseph P; Paule, Merle G; Slikker, William; Wang, Cheng

2014-05-01

Propofol is a widely used general anesthetic. A growing body of data suggests that perinatal exposure to general anesthetics can result in long-term deleterious effects on brain function. In the developing brain there is evidence that general anesthetics can cause cell death, synaptic remodeling, and altered brain cell morphology. Acetyl-L-carnitine (L-Ca), an anti-oxidant dietary supplement, has been reported to prevent neuronal damage from a variety of causes. To evaluate the ability of L-Ca to protect against propofol-induced neuronal toxicity, neural stem cells were isolated from gestational day 14 rat fetuses and on the eighth day in culture were exposed for 24h to propofol at 10, 50, 100, 300 and 600 μM, with or without L-Ca (10 μM). Markers of cellular proliferation, mitochondrial health, cell death/damage and oxidative damage were monitored to determine: (1) the effects of propofol on neural stem cell proliferation; (2) the nature of propofol-induced neurotoxicity; (3) the degree of protection afforded by L-Ca; and (4) to provide information regarding possible mechanisms underlying protection. After propofol exposure at a clinically relevant concentration (50 μM), the number of dividing cells was significantly decreased, oxidative DNA damage was increased and a significant dose-dependent reduction in mitochondrial function/health was observed. No significant effect on lactase dehydrogenase (LDH) release was observed at propofol concentrations up to 100 μM. The oxidative damage at 50 μM propofol was blocked by L-Ca. Thus, clinically relevant concentrations of propofol induce dose-dependent adverse effects on rat embryonic neural stem cells by slowing or stopping cell division/proliferation and causing cellular damage. Elevated levels of 8-oxoguanine suggest enhanced oxidative damage [reactive oxygen species (ROS) generation] and L-Ca effectively blocks at least some of the toxicity of propofol, presumably by scavenging oxidative species and/or reducing their production. Published by Elsevier B.V.

Protective effect of hexane and ethanol extract of piper longum L. On gentamicin-induced hair cell loss in neonatal cultures.

PubMed

Yadav, Mukesh Kumar; Choi, June; Song, Jae-Jun

2014-03-01

Gentamicin (GM) is a commonly used aminoglycoside antibiotic that generates free oxygen radicals within the inner ear, which can cause vestibulo-cochlear toxicity and permanent damage to the sensory hair cells and neurons. Piper longum L. (PL) is a well-known spice and traditional medicine in Asia and Pacific islands, which has been reported to exhibit a wide spectrum of activity, including antioxidant activity. In this study, we evaluated the effect of hexane:ethanol (2:8) PL extract (subfraction of PL [SPL] extract) on GM-induced hair cell loss in basal, middle and apical regions in a neonatal cochlea cultures. The protective effects of SPL extract were measured by phalloidin staining of cultures from postnatal day 2-3 mice with GM-induced hair cell loss. The anti-apoptosis activity of SPL extract was measured using double labeling by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and myosin-7a staining. The radical-scavenging activity of SPL extract was assessed using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. SPL extract at a concentration of 1 µg/mL significantly inhibited GM-induced hair cell loss at basal and middle region of cochlea, while 5 µg/mL was effective against apical region hair cell loss. The protective effect of SPL extract was concentration dependent and hair cells retained their stereocilia in explants treated with SPL extract prior to treatment with 0.3 mM GM. SPL extract decreased GM-induced apoptosis of hair cells as assessed by TUNEL staining. The outer hair and inner hair counts were not decreased in SPL extract treated groups in compare to GM treated explants. Additionally, SPL extract showed concentration dependent radical scavenging activity in a DPPH assay. An anti-apoptosis effect and potent radical scavenger activity of SPL extract protects from GM-induced hair cell loss at basal, middle and apical regions in neonatal cochlea cultures.

Protective effect of Dendrobium officinale polysaccharides on H2O2-induced injury in H9c2 cardiomyocytes.

PubMed

Zhao, Xiaoyan; Dou, Mengmeng; Zhang, Zhihao; Zhang, Duoduo; Huang, Chengzhi

2017-10-01

The preliminary studies have shown that Dendrobium officinale possessed therapeutic effects on hypertension and atherosclerosis. Studies also reported that Dendrobium officinale polysaccharides showed antioxidant capabilities. However, little is known about its effects on myocardial cells under oxidative stress. The present study was designed to study the protective effect of Dendrobium officinale polysaccharides against H 2 O 2 -induced oxidative stress in H9c2 cells. MTT assay was carried out to determine the cell viability of H9c2 cells when pretreated with Dendrobium officinale polysaccharides. Fluorescent microscopy measurements were performed for evaluating the apoptosis in H9c2 cells. Furthermore, effects of Dendrobium officinale polysaccharides on the activities of antioxidative indicators (malondialdehyde, superoxide dismutase), reactive oxygen species (ROS) production and mitochondrial membrane potential (MMP) levels were analyzed. Dendrobium officinale polysaccharides attenuated H 2 O 2 -induced cell death, as determined by the MTT assay. Dendrobium officinale polysaccharides decreased malondialdehyde levels, increased superoxide dismutase activities, and inhibited the generation of intracellular ROS. Moreover, pretreatment with Dendrobium officinale polysaccharides also inhibited apoptosis and increased the MMP levels in H9c2 cells. These results suggested the protective effects of Dendrobium officinale polysaccharides against H 2 O 2 -induced injury in H9c2 cells. The results also indicated the anti-oxidative capability of Dendrobium officinale polysaccharides. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Efficacy of Glutathione in Ameliorating Sulfur Mustard Analog-Induced Toxicity in Cultured Skin Epidermal Cells and in SKH-1 Mouse Skin In Vivo

PubMed Central

Tewari-Singh, Neera; Agarwal, Chapla; Huang, Jie; Day, Brian J.; White, Carl W.

2011-01-01

Exposure to chemical warfare agent sulfur mustard (HD) is reported to cause GSH depletion, which plays an important role in HD-linked oxidative stress and skin injury. Using the HD analog 2-chloroethyl ethyl sulfide (CEES), we evaluated the role of GSH and its efficacy in ameliorating CEES-caused skin injury. Using mouse JB6 and human HaCaT epidermal keratinocytes, we observed both protective and therapeutic effects of exogenous GSH (1 or 10 mM) in attenuating a CEES-caused decrease in cell viability and DNA synthesis, as well as S and G2M phase arrest in cell cycle progression. However, the protective effect of GSH was stronger than its ability to reverse CEES-induced cytotoxic effect. The observed effect of GSH could be associated with an increase in intracellular GSH levels after its treatment before or after CEES exposure, which strongly depleted cellular GSH levels. N-Acetyl cysteine, a GSH precursor, also showed both protective and therapeutic effects against CEES-caused cytotoxicity. Buthionine sulfoximine, which reduces cellular GSH levels, caused an increased CEES cytotoxicity in both JB6 and HaCaT cells. In further studies translating GSH effects in cell culture, pretreatment of mice with 300 mg/kg GSH via oral gavage 1 h before topical application of CEES resulted in significant protection against CEES-caused increase in skin bifold and epidermal thickness, apoptotic cell death, and myeloperoxidase activity, which could be associated with increased skin GSH levels. Together, these results highlight GSH efficacy in ameliorating CEES-caused skin injury and further support the need for effective antioxidant countermeasures against skin injury by HD exposure. PMID:20974699

Efficacy of glutathione in ameliorating sulfur mustard analog-induced toxicity in cultured skin epidermal cells and in SKH-1 mouse skin in vivo.

PubMed

Tewari-Singh, Neera; Agarwal, Chapla; Huang, Jie; Day, Brian J; White, Carl W; Agarwal, Rajesh

2011-02-01

Exposure to chemical warfare agent sulfur mustard (HD) is reported to cause GSH depletion, which plays an important role in HD-linked oxidative stress and skin injury. Using the HD analog 2-chloroethyl ethyl sulfide (CEES), we evaluated the role of GSH and its efficacy in ameliorating CEES-caused skin injury. Using mouse JB6 and human HaCaT epidermal keratinocytes, we observed both protective and therapeutic effects of exogenous GSH (1 or 10 mM) in attenuating a CEES-caused decrease in cell viability and DNA synthesis, as well as S and G(2)M phase arrest in cell cycle progression. However, the protective effect of GSH was stronger than its ability to reverse CEES-induced cytotoxic effect. The observed effect of GSH could be associated with an increase in intracellular GSH levels after its treatment before or after CEES exposure, which strongly depleted cellular GSH levels. N-Acetyl cysteine, a GSH precursor, also showed both protective and therapeutic effects against CEES-caused cytotoxicity. Buthionine sulfoximine, which reduces cellular GSH levels, caused an increased CEES cytotoxicity in both JB6 and HaCaT cells. In further studies translating GSH effects in cell culture, pretreatment of mice with 300 mg/kg GSH via oral gavage 1 h before topical application of CEES resulted in significant protection against CEES-caused increase in skin bifold and epidermal thickness, apoptotic cell death, and myeloperoxidase activity, which could be associated with increased skin GSH levels. Together, these results highlight GSH efficacy in ameliorating CEES-caused skin injury and further support the need for effective antioxidant countermeasures against skin injury by HD exposure.

Distinct Effects of Saracatinib on Memory CD8+ T-cell Differentiation

PubMed Central

Takai, Shinji; Sabzevari, Helen; Farsaci, Benedetto; Schlom, Jeffrey; Greiner, John W.

2012-01-01

Immunologic memory involving CD8+ T-cells is a hallmark of an adaptive antigen-specific immune response and comprises a critical component of protective immunity. Designing approaches that enhance long-term T-cell memory would, for the most part, fortify vaccines and enhance host protection against infectious diseases and, perhaps, cancer immunotherapy. A better understanding of the cellular programs involved in the antigen-specific T-cell response has led to new approaches that target the magnitude and quality of the memory T-cell response. Here we show that T-cells from T-cell receptor transgenic mice for the nucleoprotein of influenza virus NP68 exhibit the distinct phases priming, expansion, contraction, memory - of an antigen-specific T-cell response when exposed in vitro to the cognate peptide. Saracatinib, a specific inhibitor of Src family kinases, administered at low doses during the expansion or contraction phases, increased CD62Lhigh/CD44high central memory CD8+ T-cells and IFN-γ production, while suppressing immunity when added during the priming phase. These effects by saracatinib were not accompanied by the expected decline of Src family kinases, but were accompanied by Akt-mTOR suppression and/or mediated via another pathway. Increased central memory cells by saracatinib were recapitulated in mice using a poxvirus-based influenza vaccine, thus underscoring the importance of dose and timing of the inhibitor in the context of memory T-cell differentiation. Finally, vaccine plus saracatinib treatment showed better protection against tumor challenge. The immune-potentiating effects on CD8+ T-cells by a low dose of saracatinib might afford better protection from pathogen or cancer when combined with vaccine. PMID:22450814

Development of nickel-metal hydride cell: An update

NASA Technical Reports Server (NTRS)

Kuwajima, S.; Kusawake, Hiroaki; Nakatani, Kensuke; Yano, Y.

1994-01-01

This paper presents in viewgraph format an overview of NASDA's evaluation of commercial nickel metal-hydride (Ni-MH) cells and the development and testing of Ni-MH cells for use in space. The commercial cells are concluded to be feasible and suitable for use in LEO; for GEO, the durability for overcharge is needed because long-term charge retention is required. For the aerospace Ni-MH cell design, two activation procedures are applied to evaluate the effect of the difference in the amount of overcharge protection and precharge. Specific energy of the Ni-MH cell is nearly accomplished at 50 Wh/kg. Initial characteristics indicate the effect derived from precharge. Thirty-five amp-hour class Ni-MH cells have good performance for LEO cycle of 25 and 40 percent DOD up to 3000 cycles as similar to commercial cells. The effect of the difference in the amount of overcharge protection will appear in life test.

Multiple protective effect of peptides released from Olea europaea and Prunus persica seeds against oxidative damage and cancer cell proliferation.

PubMed

Hernández-Corroto, Ester; Marina, María Luisa; García, María Concepción

2018-04-01

The long exposition to reactive species results in oxidative stress which has been related with the development of cancer and other serious diseases. Olea europaea and Prunus persica seeds present a high protein content and preliminary results demonstrated their high potency to obtain bioactive peptides. The protective effect against oxidative damage exerted by peptides released from Olea europaea and Prunus persica seeds has been evaluated in this work. Seed hydrolysates showed protection against oxidation through four different mechanisms: inhibition of the formation of hydroxyl radicals, scavenging of free radicals, reduction of oxidizing compounds, and inhibition of lipid peroxidation. Moreover, seed hydrolysates also reduced the oxidative stress induced by an oxidizing agent on human cancer cells. Despite protection evaluated by individual mechanisms seemed to be significantly affected by the seed genotype, overall protection of seed hydrolysates was not so different. Seeds hydrolysates were not cytotoxic on normal cells but they demonstrated antiproliferative effect on human cancer cells (HeLa, PC-3, and HT-29). Peptides in all seed hydrolysates were sequenced by RP-HPLC-ESI-Q-TOF. Eighteen common peptides were observed among olive seed hydrolysates while a wider variability was observed among Prunus seed hydrolysates. Copyright © 2018 Elsevier Ltd. All rights reserved.

Retino-protective effect of Bucida buceras against oxidative stress induced by H2O2 in human retinal pigment epithelial cells line.

PubMed

Iloki-Assanga, Simon Bernard; Lewis-Luján, Lidianys María; Fernández-Angulo, Daniela; Gil-Salido, Armida Andrea; Lara-Espinoza, Claudia Lizeth; Rubio-Pino, José Luis

2015-07-29

Reactive Oxygen Species (ROS) impair the physiological functions of Retinal Pigment Epithelial (RPE) cells, which are known as one major cause of age-related macular degeneration and retinopathy diseases. The purpose of this study is to explore the cytoprotective effects of the antioxidant Bucida buceras extract in co-treatment with hydrogen peroxide (H2O2) delivery as a single addition or with continuous generation using glucose oxidase (GOx) in ARPE-19 cell cultures. The mechanism of Bucida buceras extract is believed to be associated with their antioxidant capacity to protect cells against oxidative stress. A comparative oxidative stress H2O2-induced was performed by addition and enzymatic generation using glucose oxidase on human retinal pigment epithelial cells line. H2O2-induced injury was measured by toxic effects (cell death and apoptotic pathway) and intracellular redox status: glutathione (GSH), antioxidant enzymes (catalase and glutathione peroxidase) and reducing power (FRAP). The retino-protective effect of co-treatment with Bucida buceras extract on H2O2-induced human RPE cell injury was investigated by cell death (MTT assay) and oxidative stress biomarkers (H2O2, GSH, CAT, GPx and FRAP). Bucida buceras L. extract is believed to be associated with the ability to prevent cellular oxidative stress. When added as a pulse, H2O2 is rapidly depleted and the cytotoxicity analyses show that cells can tolerate short exposure to high peroxide doses delivered as a pulse but are susceptible to lower chronic doses. Co-treatment with Bucida buceras was able to protect the cells against H2O2-induced injury. In addition to preventing cell death treatment with antioxidant plant could also reverse the significant decrease in GSH level, catalase activity and reducing power caused by H2O2. These findings suggest that Bucida buceras could protect RPE against ocular pathogenesis associated with oxidative stress induced by H2O2-delivered by addition and enzymatic generation.

5-AIQ inhibits H2O2-induced apoptosis through reactive oxygen species scavenging and Akt/GSK-3β signaling pathway in H9c2 cardiomyocytes.

PubMed

Park, Eun-Seok; Kang, Jun Chul; Kang, Do-Hyun; Jang, Yong Chang; Yi, Kyu Yang; Chung, Hun-Jong; Park, Jong Seok; Kim, Bokyung; Feng, Zhong-Ping; Shin, Hwa-Sup

2013-04-01

Poly(adenosine 5'-diphosphate ribose) polymerase (PARP) is a nuclear enzyme activated by DNA strand breaks and plays an important role in the tissue injury associated with ischemia and reperfusion. The aim of the present study was to investigate the protective effect of 5-aminoisoquinolinone (5-AIQ), a PARP inhibitor, against oxidative stress-induced apoptosis in H9c2 cardiomyocytes. 5-AIQ pretreatment significantly protected against H2O2-induced cell death, as determined by the XTT assay, cell counting, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay, and Western blot analysis of apoptosis-related proteins such as caspase-3, Bax, and Bcl-2. Upregulation of antioxidant enzymes such as manganese superoxide dismutase and catalase accompanied the protective effect of 5-AIQ on H2O2-induced cell death. Our data also showed that 5-AIQ pretreatment protected H9c2 cells from H2O2-induced apoptosis by triggering activation of Akt and glycogen synthase kinase-3β (GSK-3β), and that the protective effect of 5-AIQ was diminished by the PI3K inhibitor LY294002 at a concentration that effectively abolished 5-AIQ-induced Akt and GSK-3β activation. In addition, inhibiting the Akt/GSK-3β pathway by LY294002 significantly attenuated the 5-AIQ-mediated decrease in cleaved caspase-3 and Bax activation and H9c2 cell apoptosis induction. Taken together, these results demonstrate that 5-AIQ prevents H2O2-induced apoptosis in H9c2 cells by reducing intracellular reactive oxygen species production, regulating apoptosis-related proteins, and activating the Akt/GSK-3β pathway. Copyright © 2013 Elsevier Inc. All rights reserved.

The protective role of isorhamnetin on human brain microvascular endothelial cells from cytotoxicity induced by methylglyoxal and oxygen-glucose deprivation.

PubMed

Li, Wenlu; Chen, Zhigang; Yan, Min; He, Ping; Chen, Zhong; Dai, Haibin

2016-02-01

As the first target of stroke, cerebral endothelial cells play a key role in brain vascular repair and maintenance, and their function is impeded in diabetes. Methylglyoxal (MGO), a reactive dicarbonyl produced during glucose metabolism, accumulates in diabetic patients. MGO and MGO-induced advanced glycation end-products (AGEs) could ameliorate stroke-induced brain vascular damage, closely related with ECs dysfunction. Using MGO plus oxygen-glucose deprivation (OGD) to mimic diabetic stroke, we reported the protective effect of isorhamnetin on OGD-induced cytotoxicity after MGO treatment on primary human brain microvascular endothelial cells (HBMEC) and explored the underlying mechanisms. Treatment of MGO for 24 h significantly enhanced 3-h OGD-induced HBMEC toxic effect, which was inhibited by pretreatment of isorhamnetin (100 μmol/L). Moreover, the protective effect of isorhamnetin is multiple function dependent, which includes anti-inflammation, anti-oxidative stress and anti-apoptosis effects. Besides its well-known inhibition on the mitochondria-dependent or intrinsic apoptotic pathway, isorhamnetin also reduced activation of the extrinsic apoptotic pathway, as characterized by the decreased expression and activity of caspase 3 and caspase 8. Furthermore, pretreatment with isorhamnetin specifically inhibited FAS/FASL expression and suppressed nuclear factor-kappa B nuclear translocation. Taken together, our results indicated that isorhamnetin protected against OGD-induced cytotoxicity after MGO treatment in cultured HBMEC due to its multiple protective effects and could inhibit Fas-mediated extrinsic apoptosis. Therefore, isorhamnetin is a promising reagent for the treatment of hyperglycemia and ischemia-induced cerebral vascular degeneration. A proposed model of the potential protective mechanism of isorhamnetin, a metabolite of quercetin, on methylglyoxal (MGO) treatment plus oxygen-glucose deprivation (OGD) exposure-induced cytotoxicity in cultured human brain microvascular endothelial cells. Isorhamnetin inhibits FasL-mediated extrinsic apoptosis and neurotrophic factor κB (NF-κB) nuclear translocation, which can induce the cell DNA damage. Therefore, the protective effect of isorhamnetin occurs through multiple functions, including anti-inflammation, anti-oxidative stress and anti-apoptosis. Therefore, isorhamnetin is a promising reagent for the treatment of hyperglycemia and ischemia-induced cerebral vascular degeneration. © 2015 International Society for Neurochemistry.

Protecting Mammalian Hair Cells from Aminoglycoside-Toxicity: Assessing Phenoxybenzamine's Potential.

PubMed

Majumder, Paromita; Moore, Paulette A; Richardson, Guy P; Gale, Jonathan E

2017-01-01

Aminoglycosides (AGs) are widely used antibiotics because of their low cost and high efficacy against gram-negative bacterial infection. However, AGs are ototoxic, causing the death of sensory hair cells in the inner ear. Strategies aimed at developing or discovering agents that protect against aminoglycoside ototoxicity have focused on inhibiting apoptosis or more recently, on preventing antibiotic uptake by the hair cells. Recent screens for ototoprotective compounds using the larval zebrafish lateral line identified phenoxybenzamine as a potential protectant for aminoglycoside-induced hair cell death. Here we used live imaging of FM1-43 uptake as a proxy for aminoglycoside entry, combined with hair-cell death assays to evaluate whether phenoxybenzamine can protect mammalian cochlear hair cells from the deleterious effects of the aminoglycoside antibiotic neomycin. We show that phenoxybenzamine can block FM1-43 entry into mammalian hair cells in a reversible and dose-dependent manner, but pre-incubation is required for maximal inhibition of entry. We observed differential effects of phenoxybenzamine on FM1-43 uptake in the two different types of cochlear hair cell in mammals, the outer hair cells (OHCs) and inner hair cells (IHCs). The requirement for pre-incubation and reversibility suggests an intracellular rather than an extracellular site of action for phenoxybenzamine. We also tested the efficacy of phenoxybenzamine as an otoprotective agent. In mouse cochlear explants the hair cell death resulting from 24 h exposure to neomycin was steeply dose-dependent, with 50% cell death occurring at ~230 μM for both IHC and OHC. We used 250 μM neomycin in subsequent hair-cell death assays. At 100 μM with 1 h pre-incubation, phenoxybenzamine conferred significant protection to both IHCs and OHCs, however at higher concentrations phenoxybenzamine itself showed clear signs of ototoxicity and an additive toxic effect when combined with neomycin. These data do not support the use of phenoxybenzamine as a therapeutic agent in mammalian inner ear. Our findings do share parallels with the observations from the zebrafish lateral line model but they also highlight the necessity for validation in the mammalian system and the potential for differential effects on sensory hair cells from different species, in different systems and even between cells in the same organ.

The effect of zinc (Zn) content to cell potential value and efficiency aluminium sacrificial anode in 0.2 M sulphuric acid environment

NASA Astrophysics Data System (ADS)

Akranata, Ahmad Ridho; Sulistijono, Awali, Jatmoko

2018-04-01

Sacrificial anode is sacirifial component that used to protect steel from corrosion. Generally, the component are made of aluminium and zinc in water environment. Sacrificial anode change the protected metal structure become cathodic with giving current. The advantages of aluminium is corrosion resistance, non toxicity and easy forming. Zinc generally used for coating in steel to prevent steel from corrosion. This research was conducted to analyze the effect of zinc content to the value of cell potential and efficiency aluminium sacrificial anode with sand casting method in 0.2 M sulphuric acid environment. The sacrificial anode fabrication made with alloying aluminium and zinc metals with variation composition of alloy with pure Al, Al-3Zn, Al-6Zn, and Al-9Zn with open die sand casting process. The component installed with ASTM A36 steel. After the research has been done the result showed that addition of zinc content increase the cell potential, protection efficiency, and anode efficiency from steel plate. Cell potential value measurement and weight loss measurement showed that addition of zinc content increase the cell potential value into more positive that can protected the ASTM A36 steel more efficiently that showed in weight loss measurement where the protection efficiency and anodic efficiency of Al-9Zn sacrificial anode is better than protection efficiency and anodic efficiency of pure Al. The highest protection efficiency gotten by Al-9Zn alloy

ATR Kinase Inhibition Protects Non-cycling Cells from the Lethal Effects of DNA Damage and Transcription Stress*

PubMed Central

Kemp, Michael G.; Sancar, Aziz

2016-01-01

ATR (ataxia telangiectasia and Rad-3-related) is a protein kinase that maintains genome stability and halts cell cycle phase transitions in response to DNA lesions that block DNA polymerase movement. These DNA replication-associated features of ATR function have led to the emergence of ATR kinase inhibitors as potential adjuvants for DNA-damaging cancer chemotherapeutics. However, whether ATR affects the genotoxic stress response in non-replicating, non-cycling cells is currently unknown. We therefore used chemical inhibition of ATR kinase activity to examine the role of ATR in quiescent human cells. Although ATR inhibition had no obvious effects on the viability of non-cycling cells, inhibition of ATR partially protected non-replicating cells from the lethal effects of UV and UV mimetics. Analyses of various DNA damage response signaling pathways demonstrated that ATR inhibition reduced the activation of apoptotic signaling by these agents in non-cycling cells. The pro-apoptosis/cell death function of ATR is likely due to transcription stress because the lethal effects of compounds that block RNA polymerase movement were reduced in the presence of an ATR inhibitor. These results therefore suggest that whereas DNA polymerase stalling at DNA lesions activates ATR to protect cell viability and prevent apoptosis, the stalling of RNA polymerases instead activates ATR to induce an apoptotic form of cell death in non-cycling cells. These results have important implications regarding the use of ATR inhibitors in cancer chemotherapy regimens. PMID:26940878

Artemisinin protects PC12 cells against β-amyloid-induced apoptosis through activation of the ERK1/2 signaling pathway.

PubMed

Zeng, Zhiwen; Xu, Jinying; Zheng, Wenhua

2017-08-01

Accumulating evidence displays that an abnormal deposition of amyloid beta-peptide (Aβ) is the primary cause of the pathogenesis of Alzheimer's disease (AD). And therefore the elimination of Aβ is regarded as an important strategy for AD treatment. The discovery of drug candidates using culture neuronal cells against Aβ peptide toxicity is believed to be an effective approach to develop drug for the treatment of AD patients. We have previously showed that artemisinin, a FDA-approved anti-malaria drug, has neuroprotective effects recently. In the present study, we aimed to investigate the effects and potential mechanism of artemisinin in protecting neuronal PC12 cells from toxicity of β amyloid peptide. Our studies revealed that artemisinin, in clinical relevant concentration, protected and rescued PC12 cells from Aβ25-35-induced cell death. Further study showed that artemisinin significantly ameliorated cell death due to Aβ25-35 insult by restoring abnormal changes in nuclear morphology, lactate dehydrogenase, intracellular ROS, mitochondrial membrane potential and activity of apoptotic caspase. Western blotting analysis demonstrated that artemisinin activated extracellular regulated kinase ERK1/2 but not Akt survival signaling. Consistent with the role of ERK1/2, preincubation of cells with ERK1/2 pathway inhibitor PD98059 blocked the effect of artemisinin while PI3K inhibitor LY294002 has no effect. Moreover, Aβ1-42 also caused cells death of PC12 cells while artemisinin suppressed Aβ1-42 cytotoxicity in PC12 cells. Taken together, these results, at the first time, suggest that artemisinin is a potential protectant against β amyloid insult through activation of the ERK1/2 pathway. Our finding provides a potential application of artemisinin in prevention and treatment of AD. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

BDNF/TrkB signaling protects HT-29 human colon cancer cells from EGFR inhibition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brunetto de Farias, Caroline; Children's Cancer Institute, 90420-140 Porto Alegre, RS; Laboratory of Neuropharmacology and Neural Tumor Biology, Department of Pharmacology, Institute for Basic Health Sciences, Federal University of Rio Grande do Sul, 90050-170 Porto Alegre, RS

2012-08-24

Highlights: Black-Right-Pointing-Pointer BDNF protected HT-29 colorectal cancer cells from the antitumor effect of cetuximab. Black-Right-Pointing-Pointer TrkB inhibition potentiated the antitumor effect of cetuximab. Black-Right-Pointing-Pointer BDNF/TrkB signaling might be involved in resistance to anti-EGFR therapy. -- Abstract: The clinical success of targeted treatment of colorectal cancer (CRC) is often limited by resistance to anti-epidermal growth factor receptor (EGFR) therapy. The neurotrophin brain-derived neurotrophic factor (BDNF) and its receptor TrkB have recently emerged as anticancer targets, and we have previously shown increased BDNF levels in CRC tumor samples. Here we report the findings from in vitro experiments suggesting that BDNF/TrkB signaling canmore » protect CRC cells from the antitumor effects of EGFR blockade. The anti-EGFR monoclonal antibody cetuximab reduced both cell proliferation and the mRNA expression of BDNF and TrkB in human HT-29 CRC cells. The inhibitory effect of cetuximab on cell proliferation and survival was counteracted by the addition of human recombinant BDNF. Finally, the Trk inhibitor K252a synergistically enhanced the effect of cetuximab on cell proliferation, and this effect was blocked by BDNF. These results provide the first evidence that increased BDNF/TrkB signaling might play a role in resistance to EGFR blockade. Moreover, it is possible that targeting TrkB could potentiate the anticancer effects of anti-EGFR therapy.« less

Space environmental effect on solar cells: LDEF and other flight tests

NASA Technical Reports Server (NTRS)

Gruenbaum, Peter; Dursch, Harry

1995-01-01

This paper summarizes results of several experiments flown on the Long Duration Exposure Facility (LDEF) to examine the effects of the space environment on materials and technologies to be used in solar arrays. The various LDEF experiments are compared to each other as well as to other solar cell flight data published in the literature. Data on environmental effects such as atomic oxygen, ultraviolet light, micrometeoroids and debris, and charged particles are discussed in detail. The results from the LDEF experiments allow us to draw several conclusions. Atomic oxygen erodes unprotected silver interconnects, unprotected Kapton, and polymer cell covers, but certain dielectric coatings can protect both silver and Kapton. Cells that had wrap-around silver contacts sometimes showed erosion at the edges, but more recently developed wrap-through cells are not expected to have these problems. Micrometeoroid and debris damage is limited to the area close to the impact, and microsheet covers provide the cells with some protection. Damage from charged particles was as predicted, and the cell covers provided adequate protection. In general, silicon cells with microsheet covers showed very little degradation, and solar modules showed less than 3 percent degradation, except when mechanically damaged. The solar cell choices for the Space Station solar array are supported by the data from LDEF.

Reduced cytotoxicity in PCB-exposed Chinese Hamster Ovary (CHO) cells pretreated with vitamin E.

PubMed

Murati, Teuta; Šimić, Branimir; Pleadin, Jelka; Vukmirović, Maja; Miletić, Marina; Durgo, Ksenija; Kniewald, Jasna; Kmetič, Ivana

2017-01-01

The aim of this study was to evaluate protective effects of vitamin E (50 -150 μM) in ovary cells upon cytotoxic effects induced by two structurally distinct PCB congeners - planar "dioxin-like" PCB 77 and non-planar di-ortho-substituted PCB 153 with an emphasis on identifying differences in the mechanism of vitamin E action depending on the structure of congeners. Application of three bioassays confirmed that PCBs decrease ovarian cell proliferation with slightly profound effects of PCB 77. PCB - induced ROS production and lipid peroxidation were significant for both congeners with also more noticeable effect for PCB 77. Vitamin E pre-incubation has improved viability of cells, reduced ROS formation and lipid peroxidation induced by PCBs' treatment. Preincubation with vitamin E was more effective when cells where treated with non-planar PCB 153. Altogether, vitamin E action was protective, congener specific and more effective when ovary cells were exposed to ortho-substituted PCB congener. Copyright © 2016 Elsevier Ltd. All rights reserved.

A fully integrated new paradigm for lithium's mode of action - lithium utilizes latent cellular fail-safe mechanisms.

PubMed

van Woerkom, Arthur Ernst

2017-01-01

It is proposed that lithium's therapeutic effects occur indirectly by augmenting a cascade of protective "fail-safe" pathways pre-configured to activate in response to a dangerous low cell [Mg ++ ] situation, eg, posttraumatic brain injury, alongside relative cell adenosine triphosphate depletion. Lithium activates cell protection, as it neatly mimics a lowered intracellular [Mg ++ ] level.

Gypenosides protect retinal pigment epithelium cells from oxidative stress.

PubMed

Alhasani, Reem Hasaballah; Biswas, Lincoln; Tohari, Ali Mohammad; Zhou, Xinzhi; Reilly, James; He, Jian-Feng; Shu, Xinhua

2018-02-01

Oxidative stress plays a critical role in the pathogenesis of retinal degeneration. Gypenosides are the major functional components isolated from Gynostemma pentaphyllum. They have been shown to protect against oxidative stress and inflammation and have also demonstrated a protective effect on experimental optic neuritis. In order to determine the protective properties of gypenosides against oxidative stress in human retinal pigment epithelium (RPE) cells, ARPE-19 cells were treated with H 2 O 2 or H 2 O 2 plus gypenosides for 24 h. ARPE-19 cells co-treated with gypenosides had significantly increased cell viability and decreased cell death rate when compared to cells treated with H 2 O 2 alone. The level of GSH, the activities of SOD and catalase, and the expression of NRF2 and antioxidant genes were notably decreased, while there were marked increases in ROS, MDA and pro-inflammatory cytokines in ARPE-19 cells exposed to H 2 O 2 ; co-treatment with gypenosides significantly counteract these changes. Our study suggests that gypenosides protect RPE cells from oxidative damage and offer therapeutic potential for the treatment of retinal degeneration. Copyright © 2017 Elsevier Ltd. All rights reserved.

CD8 T-cell-mediated protection against liver-stage malaria: lessons from a mouse model

PubMed Central

Van Braeckel-Budimir, Natalija; Harty, John T.

2014-01-01

Malaria is a major global health problem, with severe mortality in children living in sub-Saharan Africa, and there is currently no licensed, effective vaccine. However, vaccine-induced protection from Plasmodium infection, the causative agent of malaria, was established for humans in small clinical trials and for rodents in the 1960s. Soon after, a critical role for memory CD8 T cells in vaccine-induced protection against Plasmodium liver-stage infection was established in rodent models and is assumed to apply to humans. However, these seminal early studies have led to only modest advances over the ensuing years in our understanding the basic features of memory CD8 T cells required for protection against liver-stage Plasmodium infection, an issue which has likely impeded the development of effective vaccines for humans. Given the ethical and practical limitations in gaining mechanistic insight from human vaccine and challenge studies, animal models still have an important role in dissecting the basic parameters underlying memory CD8 T-cell immunity to Plasmodium. Here, we will highlight recent data from our own work in the mouse model of Plasmodium infection that identify quantitative and qualitative features of protective memory CD8 T-cell responses. Finally, these lessons will be discussed in the context of recent findings from clinical trials of vaccine-induced protection in controlled human challenge models. PMID:24936199

Magnolol protects against oxidative stress-mediated neural cell damage by modulating mitochondrial dysfunction and PI3K/Akt signaling.

PubMed

Dong, Liqun; Zhou, Shu; Yang, Xiaohua; Chen, Qianming; He, Yang; Huang, Wen

2013-07-01

Magnolol, an orally available compound from Magnolia officinalis used widely in traditional herbal medicine against a variety of neuronal diseases, possesses potent antioxidant properties and protects the brain against oxidative damage. The aim of the work is to examine the protective mechanisms of magnolol on human neuroblastoma SH-SY5Y cells against apoptosis induced by the neurotoxin acrolein, which can cause neurodegenerative disorders by inducing oxidative stress. By investigating the effect of magnolol on neural cell damage induced by the neurotoxin acrolein, we found that magnolol pretreatment significantly attenuated acrolein-induced oxidative stress through inhibiting reactive oxygen species accumulation caused by intracellular glutathione depletion and nicotinamide adenine dinucleotide phosphate oxidase activation. We next examined the signaling cascade(s) involved in magnolol-mediated antiapoptotic effects. The results showed that acrolein induced SH-SY5Y cell apoptosis by activating mitochondria/caspase and MEK/ERK signaling pathways. Our findings provide the first evidence that magnolol protects SH-SY5Y cells against acrolein-induced oxidative stress and prolongs SH-SY5Y cell survival through regulating JNK/mitochondria/caspase, PI3K/MEK/ERK, and PI3K/Akt/FoxO1 signaling pathways.

Transduced Tat-DJ-1 Protein Protects against Oxidative Stress-Induced SH-SY5Y Cell Death and Parkinson Disease in a Mouse Model

PubMed Central

Jeong, Hoon Jae; Kim, Dae Won; Woo, Su Jung; Kim, Hye Ri; Kim, So Mi; Jo, Hyo Sang; Park, Meeyoung; Kim, Duk-Soo; Kwon, Oh-Shin; Hwang, In Koo; Han, Kyu Hyung; Park, Jinseu; Eum, Won Sik; Choi, Soo Young

2012-01-01

Parkinson’s disease (PD) is a well known neurodegenerative disorder characterized by selective loss of dopaminergic neurons in the substantia nigra pars compact (SN). Although the exact mechanism remains unclear, oxidative stress plays a critical role in the pathogenesis of PD. DJ-1 is a multifunctional protein, a potent antioxidant and chaperone, the loss of function of which is linked to the autosomal recessive early onset of PD. Therefore, we investigated the protective effects of DJ-1 protein against SH-SY5Y cells and in a PD mouse model using a cell permeable Tat-DJ-1 protein. Tat-DJ-1 protein rapidly transduced into the cells and showed a protective effect on 6-hydroxydopamine (6-OHDA)-induced neuronal cell death by reducing the reactive oxygen species (ROS). In addition, we found that Tat-DJ-1 protein protects against dopaminergic neuronal cell death in 1-methyl-4-phenyl-1,2,3,6,-tetrahydropyridine (MPTP)-induced PD mouse models. These results suggest that Tat-DJ-1 protein provides a potential therapeutic strategy for against ROS related human diseases including PD. PMID:22526393

Lycium barbarum Polysaccharides Protect Rat Corneal Epithelial Cells against Ultraviolet B-Induced Apoptosis by Attenuating the Mitochondrial Pathway and Inhibiting JNK Phosphorylation.

PubMed

Du, Shaobo; Han, Biao; Li, Kang; Zhang, Xuan; Sha, Xueli; Gao, Lan

2017-01-01

Lycium barbarum polysaccharides (LBPs) have been shown to play a key role in protecting the eyes by reducing the apoptosis induced by certain types of damage. However, it is not known whether LBPs can protect damaged corneal cells from apoptosis. Moreover, no reports have focused on the role of LBPs in guarding against ultraviolet B- (UVB-) induced apoptosis. The present study aimed to investigate the protective effect and underlying mechanism of LBPs against UVB-induced apoptosis in rat corneal epithelial (RCE) cells. The results showed that LBPs significantly prevented the loss of cell viability and inhibited cell apoptosis induced by UVB in RCE cells. LBPs also inhibited UVB-induced loss of mitochondrial membrane potential, downregulation of Bcl-2 , and upregulation of Bax and caspase-3. Finally, LBPs attenuated the phosphorylation of c-Jun NH 2 -terminal kinase (JNK) triggered by UVB. In summary, LBPs protect RCE cells against UVB-induced damage and apoptosis, and the underlying mechanism involves the attenuation of the mitochondrial apoptosis pathway and the inhibition of JNK phosphorylation.

Effects of pituitary adenylate cyclase activating polypeptide in the urinary system, with special emphasis on its protective effects in the kidney.

PubMed

Reglodi, Dora; Kiss, Peter; Horvath, Gabriella; Lubics, Andrea; Laszlo, Eszter; Tamas, Andrea; Racz, Boglarka; Szakaly, Peter

2012-04-01

Pituitary adenylate cyclase activating polypeptide (PACAP) is a widespread neuropeptide with diverse effects in the nervous system and peripheral organs. One of the most well-studied effects of PACAP is its cytoprotective action, against different harmful stimuli in a wide variety of cells and tissues. PACAP occurs in the urinary system, from the kidney to the lower urinary tract. The present review focuses on the nephroprotective effects of PACAP and summarizes data obtained regarding the protective effects of PACAP in different models of kidney pathologies. In vitro data show that PACAP protects tubular cells against oxidative stress, myeloma light chain, cisplatin, cyclosporine-A and hypoxia. In vivo data provide evidence for its protective effects in ischemia/reperfusion, cisplatin, cyclosporine-A, myeloma kidney injury, diabetic nephropathy and gentamicin-induced kidney damage. Results accumulated on the renoprotective effects of PACAP suggest that PACAP is an emerging candidate for treatment of human kidney pathologies. Copyright © 2011 Elsevier Ltd. All rights reserved.

Simultaneous Overexpression of Functional Human HO-1, E5NT and ENTPD1 Protects Murine Fibroblasts against TNF-α-Induced Injury In Vitro

PubMed Central

Cinti, Alessandro; De Giorgi, Marco; Chisci, Elisa; Arena, Claudia; Galimberti, Gloria; Farina, Laura; Bugarin, Cristina; Rivolta, Ilaria; Gaipa, Giuseppe; Smolenski, Ryszard Tom; Cerrito, Maria Grazia; Lavitrano, Marialuisa; Giovannoni, Roberto

2015-01-01

Several biomedical applications, such as xenotransplantation, require multiple genes simultaneously expressed in eukaryotic cells. Advances in genetic engineering technologies have led to the development of efficient polycistronic vectors based on the use of the 2A self-processing oligopeptide. The aim of this work was to evaluate the protective effects of the simultaneous expression of a novel combination of anti-inflammatory human genes, ENTPD1, E5NT and HO-1, in eukaryotic cells. We produced an F2A system-based multicistronic construct to express three human proteins in NIH3T3 cells exposed to an inflammatory stimulus represented by tumor necrosis factor alpha (TNF-α), a pro-inflammatory cytokine which plays an important role during inflammation, cell proliferation, differentiation and apoptosis and in the inflammatory response during ischemia/reperfusion injury in several organ transplantation settings. The protective effects against TNF-α-induced cytotoxicity and cell death, mediated by HO-1, ENTPD1 and E5NT genes were better observed in cells expressing the combination of genes as compared to cells expressing each single gene and the effect was further improved by administrating enzymatic substrates of the human genes to the cells. Moreover, a gene expression analyses demonstrated that the expression of the three genes has a role in modulating key regulators of TNF-α signalling pathway, namely Nemo and Tnfaip3, that promoted pro-survival phenotype in TNF-α injured cells. These results could provide new insights in the research of protective mechanisms in transplantation settings. PMID:26513260

Cytotoxic effector functions of T cells are not required for protective immunity against fatal Rickettsia typhi infection in a murine model of infection: Role of TH1 and TH17 cytokines in protection and pathology

PubMed Central

Rauch, Jessica; Papp, Stefanie; Kuehl, Svenja; Richardt, Ulricke; Fleischer, Bernhard; Osterloh, Anke

2017-01-01

Endemic typhus caused by Rickettsia (R.) typhi is an emerging febrile disease that can be fatal due to multiple organ pathology. Here we analyzed the requirements for protection against R. typhi by T cells in the CB17 SCID model of infection. BALB/c wild-type mice generate CD4+ TH1 and cytotoxic CD8+ T cells both of which are sporadically reactivated in persistent infection. Either adoptively transferred CD8+ or CD4+ T cells protected R. typhi-infected CB17 SCID mice from death and provided long-term control. CD8+ T cells lacking either IFNγ or Perforin were still protective, demonstrating that the cytotoxic function of CD8+ T cells is not essential for protection. Immune wild-type CD4+ T cells produced high amounts of IFNγ, induced the release of nitric oxide in R. typhi-infected macrophages and inhibited bacterial growth in vitro via IFNγ and TNFα. However, adoptive transfer of CD4+IFNγ-/- T cells still protected 30–90% of R. typhi-infected CB17 SCID mice. These cells acquired a TH17 phenotype, producing high amounts of IL-17A and IL-22 in addition to TNFα, and inhibited bacterial growth in vitro. Surprisingly, the neutralization of either TNFα or IL-17A in CD4+IFNγ-/- T cell recipient mice did not alter bacterial elimination by these cells in vivo, led to faster recovery and enhanced survival compared to isotype-treated animals. Thus, collectively these data show that although CD4+ TH1 cells are clearly efficient in protection against R. typhi, CD4+ TH17 cells are similarly protective if the harmful effects of combined production of TNFα and IL-17A can be inhibited. PMID:28222146

Polyfunctional CD4+ T Cells As Targets for Tuberculosis Vaccination

PubMed Central

Lewinsohn, Deborah A.; Lewinsohn, David M.; Scriba, Thomas J.

2017-01-01

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), remains a leading cause of morbidity and mortality worldwide, despite the widespread use of the only licensed vaccine, Bacille Calmette Guerin (BCG). Eradication of TB will require a more effective vaccine, yet evaluation of new vaccine candidates is hampered by lack of defined correlates of protection. Animal and human studies of intracellular pathogens have extensively evaluated polyfunctional CD4+ T cells producing multiple pro-inflammatory cytokines (IFN-γ, TNF-α, and IL-2) as a possible correlate of protection from infection and disease. In this study, we review the published literature that evaluates whether or not BCG and/or novel TB vaccine candidates induce polyfunctional CD4+ T cells and if these T cell responses correlate with vaccine-mediated protection. Ample evidence suggests that BCG and several novel vaccine candidates evaluated in animal models and humans induce polyfunctional CD4+ T cells. However, while a number of studies utilizing the mouse TB model support that polyfunctional CD4+ T cells are associated with vaccine-induced protection, other studies in mouse and human infants demonstrate no correlation between these T cell responses and protection. We conclude that induction of polyfunctional CD4+ T cells is certainly not sufficient and may not even be necessary to mediate protection and suggest that other functional attributes, such as additional effector functions, T cell differentiation state, tissue homing potential, or long-term survival capacity of the T cell may be equally or more important to promote protection. Thus, a correlate of protection for TB vaccine development remains elusive. Future studies should address polyfunctional CD4+ T cells within the context of more comprehensive immunological signatures of protection that include other functions and phenotypes of T cells as well as the full spectrum of immune cells and mediators that participate in the immune response against Mtb. PMID:29051764

Protective effect of NSA on intestinal epithelial cells in a necroptosis model

PubMed Central

Dong, Wei; Zhang, Min; Zhu, Yaxi; Chen, Yuanhan; Zhao, Xingchen; Li, Ruizhao; Zhang, Li; Ye, Zhiming; Liang, Xingling

2017-01-01

Objective This study aimed to investigate the protective effect of the necroptosis inhibitor necrosulfonamide (NSA) on intestinal epithelial cells using a novel in vitro necroptosis model that mimics inflammatory bowel disease (IBD). Methods 2,4,6-trinitrobenzenesulfonic acid (TNBS) was perfused into the rectum of BALB/c mice to established a colitis model. Pathologic injury and cell death were evaluated. A novel in vitro model of necroptosis was established in Caco-2 cells using TNF-α and Z-VAD-fmk, and the cells were treated with or without NSA. Morphologic changes, manner of cell death and the levels of phosphorylation of receptor-interacting protein kinase 3 (p-RIPK3) and mixed-lineage kinase domain-like (p-MLKL) were detected. Results In the TNBS-induced colitis in mice, TUNEL-positive and caspase-3-negative cells were observed in the intestinal mucosa, and p-RIPK3 was found to be elevated. Under the stimulation of TNF-α and Z-VAD-fmk, the morphologic damage in the Caco-2 cells was aggravated, the proportion of necrosis was increased, and the level of p-RIPK3 and p-MLKL were increased, confirming that the regulated cell death was necroptosis. NSA reversed the morphological abnormalities and reduced necrotic cell death induced by TNF-α and Z-VAD-fmk. Conclusion NSA can inhibit necroptosis in intestinal epithelial cells in vitro and might confer a potential protective effect against IBD. PMID:29156831

Protective effect of NSA on intestinal epithelial cells in a necroptosis model.

PubMed

Dong, Wei; Zhang, Min; Zhu, Yaxi; Chen, Yuanhan; Zhao, Xingchen; Li, Ruizhao; Zhang, Li; Ye, Zhiming; Liang, Xingling

2017-10-17

This study aimed to investigate the protective effect of the necroptosis inhibitor necrosulfonamide (NSA) on intestinal epithelial cells using a novel in vitro necroptosis model that mimics inflammatory bowel disease (IBD). 2,4,6-trinitrobenzenesulfonic acid (TNBS) was perfused into the rectum of BALB/c mice to established a colitis model. Pathologic injury and cell death were evaluated. A novel in vitro model of necroptosis was established in Caco-2 cells using TNF- α and Z-VAD-fmk, and the cells were treated with or without NSA. Morphologic changes, manner of cell death and the levels of phosphorylation of receptor-interacting protein kinase 3 (p-RIPK3) and mixed-lineage kinase domain-like (p-MLKL) were detected. In the TNBS-induced colitis in mice, TUNEL-positive and caspase-3-negative cells were observed in the intestinal mucosa, and p-RIPK3 was found to be elevated. Under the stimulation of TNF- α and Z-VAD-fmk, the morphologic damage in the Caco-2 cells was aggravated, the proportion of necrosis was increased, and the level of p-RIPK3 and p-MLKL were increased, confirming that the regulated cell death was necroptosis. NSA reversed the morphological abnormalities and reduced necrotic cell death induced by TNF- α and Z-VAD-fmk. NSA can inhibit necroptosis in intestinal epithelial cells in vitro and might confer a potential protective effect against IBD.

The protective effect of soybean phytochemicals on androgen responsive human prostate cancer cells LNCaP is likely mediated through modulation of hormone/cytokine-dependent pathways

USDA-ARS?s Scientific Manuscript database

Population studies suggested that the consumption of a soy rich diet provides protective effects against several chronic diseases including prostate cancer. However, the active components in soy, as well as the mechanisms of action of soy’s protective effects, remain unclear. It would be important t...

Huperzine A derivative M3 protects PC12 cells against sodium nitroprusside-induced apoptosis

PubMed Central

Ning, Na; Hu, Jin-feng; Yuan, Yu-he; Zhang, Xin-yuan; Dai, Jun-gui; Chen, Nai-hong

2012-01-01

Aim: To investigate the effects of M3, a derivative of huperzine A, on the apoptosis induced by sodium nitroprusside (SNP) in PC12 cells. Methods: Cell viability was detected using MTT method. Apoptosis was examined with annexin V/prodium iodide (PI) stain. The levels of reactive oxygen species (ROS) were measured using fluorophotometric quantitation. The amount of malonaldehyde (MDA) was determined with MDA detection kits. The expression of caspase-3 and Hsp70 were analyzed using Western blotting. Results: Exposure of PC12 cells to SNP (200 μmol/L) for 24 h decreased the cell viability to 69.0% of that in the control group. Pretreatment with M3 (10 μmol/L) or huperzine A (10 μmol/L) significantly protected the cells against SNP-induced injury and apoptosis; the ratio of apoptotic bodies in PC12 cells was decreased from 27.3% to 15.0%. Pretreatment with M3 (10 μmol/L) significantly decreased ROS and MDA levels, and increased the expression of Hsp70 in the cells. Quercetin (10 μmol/L) blocked the protective effect of M3, while did not influence on that of huperzine A. Conclusion: M3 protects PC12 cells against SNP-induced apoptosis, possible due to ROS scavenging and Hsp70 induction. PMID:22120967

Protective effects of resveratrol and its analogs on age-related macular degeneration in vitro.

PubMed

Kang, Jung-Hwan; Choung, Se-Young

2016-12-01

Damage of retinal pigment epithelial (RPE) cells by A2E may be critical for age-related macular degeneration (AMD) management. Accumulation and photooxidation of A2E are known to be one of the critical causes in AMD. Here, we evaluated the protective effect of resveratrol (RES), piceatannol (PIC) and RES glycones on blue-light-induced RPE cell death caused by A2E photooxidation. A2E treatment followed by blue light exposure caused significant damages on human RPE cells (ARPE-19). But the damages were attenuated by post- and pre-treatment of RES and PIC in our in vitro models. The results of cell free system and FAB-MS analysis clearly showed that the reduction of A2E by blue light exposure was significantly rescued, and that oxidized forms of A2E were significantly reduced by RES or PIC treatment. Besides, RES or PIC inhibited the intracellular accumulation of A2E. Not only RES and PIC but RES glycones showed protection of ARPE-19 cells against A2E and blue-light-induced photo-damage. These findings demonstrate that RES and its analogs may have protective effects against A2E and blue-light-induced ARPE-19 cell death through regulation of A2E accumulation as well as photooxidation of A2E. Thus RES and its analogs may be beneficial for AMD treatment.

Topical CpG Adjuvantation of a Protein-Based Vaccine Induces Protective Immunity to Listeria monocytogenes

PubMed Central

Cheng, Wing Ki; Wee, Kathleen; Kollmann, Tobias R.

2014-01-01

Robust CD8+ T cell responses are essential for immune protection against intracellular pathogens. Using parenteral administration of ovalbumin (OVA) protein as a model antigen, the effect of the Toll-like receptor 9 (TLR9) agonist, CpG oligodeoxynucleotide (ODN) 1826, as an adjuvant delivered either topically, subcutaneously, or intramuscularly on antigen-specific CD8+ T cell responses in a mouse model was evaluated. Topical CpG adjuvant increased the frequency of OVA-specific CD8+ T cells in the peripheral blood and in the spleen. The more effective strategy to administer topical CpG adjuvant to enhance CD8+ T cell responses was single-dose administration at the time of antigen injection with a prime-boost regimen. Topical CpG adjuvant conferred both rapid and long-lasting protection against systemic challenge with recombinant Listeria monocytogenes expressing the cytotoxic T lymphocyte (CTL) epitope of OVA257–264 (strain Lm-OVA) in a TLR9-dependent manner. Topical CpG adjuvant induced a higher proportion of CD8+ effector memory T cells than parenteral administration of the adjuvant. Although traditional vaccination strategies involve coformulation of antigen and adjuvant, split administration using topical adjuvant is effective and has advantages of safety and flexibility. Split administration of topical CpG ODN 1826 with parenteral protein antigen is superior to other administration strategies in enhancing both acute and memory protective CD8+ T cell immune responses to subcutaneous protein vaccines. This vaccination strategy induces rapid and persistent protective immune responses against the intracellular organism L. monocytogenes. PMID:24391136

Protective role of arzanol against lipid peroxidation in biological systems.

PubMed

Rosa, Antonella; Pollastro, Federica; Atzeri, Angela; Appendino, Giovanni; Melis, M Paola; Deiana, Monica; Incani, Alessandra; Loru, Debora; Dessì, M Assunta

2011-01-01

This study examines the protective effect of arzanol, a pyrone-phloroglucinol etherodimer from Helichrysum italicum subsp. microphyllum, against the oxidative modification of lipid components induced by Cu(2+) ions in human low density lipoprotein (LDL) and by tert-butyl hydroperoxide (TBH) in cell membranes. LDL pre-treatment with arzanol significantly preserved lipoproteins from oxidative damage at 2h of oxidation, and showed a remarkable protective effect on the reduction of polyunsaturated fatty acids and cholesterol levels, inhibiting the increase of oxidative products (conjugated dienes fatty acids hydroperoxides, 7β-hydroxycholesterol, and 7-ketocholesterol). Arzanol, at non-cytotoxic concentrations, exerted a noteworthy protection on TBH-induced oxidative damage in a line of fibroblasts derived from monkey kidney (Vero cells) and in human intestinal epithelial cells (Caco-2), decreasing, in both cell lines, the formation of oxidative products (hydroperoxides and 7-ketocholesterol) from the degradation of unsaturated fatty acids and cholesterol. The cellular uptake and transepithelial transport of the compound were also investigated in Caco-2 cell monolayers. Arzanol appeared to accumulate in Caco-2 epithelial cells. This phenol was able to pass through the intestinal Caco-2 monolayers, the apparent permeability coefficients (P(app)) in the apical-to-basolateral and basolateral-to-apical direction at 2h were 1.93±0.36×10(-5) and 2.20±0.004×10(-5)cm/s, respectively, suggesting a passive diffusion pathway. The results of the work qualify arzanol as a potent natural antioxidant with a protective effect against lipid oxidation in biological systems. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

A new ferulic acid ester from Rhodiola wallichiana var. cholaensis (Crassulaceae).

PubMed

Song, Yaling; Zhou, Jianming; Wang, Xuejing; Xie, Xue; Zhao, Yiwu; Ni, Fuyong; Huang, Wenzhe; Wang, Zhenzhong; Xiao, Wei

2018-01-01

A new ferulic acid ester, 6-feruloyloxyhexanoic acid (1), was isolated along with 10 known ones (2-11), from the concentrated water extract of Rhodiola wallichiana var. cholaensis. Their chemical structures were elucidated on the basis of extensive spectroscopic methods including Two-dimensional nuclear magnetic resonance (2D NMR) experiments. Compound 3 was isolated from this plant for the first time. The protective effects against H 2 O 2 -induced myocardial cell injury in cultured H9c2 cells were also evaluated. Compounds 1, 5 and 7-11 provided significant protective effects on H 2 O 2 -induced H9c2 cells injury at the concentration of 25 μg/mL. And the protective effects of compound 1 was also investigated by the oxygen-glucose deprivation/reperfusion (OGD/R) tests.

Glutathione and antioxidant enzymes serve complementary roles in protecting activated hepatic stellate cells against hydrogen peroxide-induced cell death.

PubMed

Dunning, Sandra; Ur Rehman, Atta; Tiebosch, Marjolein H; Hannivoort, Rebekka A; Haijer, Floris W; Woudenberg, Jannes; van den Heuvel, Fiona A J; Buist-Homan, Manon; Faber, Klaas Nico; Moshage, Han

2013-12-01

In chronic liver disease, hepatic stellate cells (HSCs) are activated, highly proliferative and produce excessive amounts of extracellular matrix, leading to liver fibrosis. Elevated levels of toxic reactive oxygen species (ROS) produced during chronic liver injury have been implicated in this activation process. Therefore, activated hepatic stellate cells need to harbor highly effective anti-oxidants to protect against the toxic effects of ROS. To investigate the protective mechanisms of activated HSCs against ROS-induced toxicity. Culture-activated rat HSCs were exposed to hydrogen peroxide. Necrosis and apoptosis were determined by Sytox Green or acridine orange staining, respectively. The hydrogen peroxide detoxifying enzymes catalase and glutathione-peroxidase (GPx) were inhibited using 3-amino-1,2,4-triazole and mercaptosuccinic acid, respectively. The anti-oxidant glutathione was depleted by L-buthionine-sulfoximine and repleted with the GSH-analogue GSH-monoethylester (GSH-MEE). Upon activation, HSCs increase their cellular glutathione content and GPx expression, while MnSOD (both at mRNA and protein level) and catalase (at the protein level, but not at the mRNA level) decreased. Hydrogen peroxide did not induce cell death in activated HSCs. Glutathione depletion increased the sensitivity of HSCs to hydrogen peroxide, resulting in 35% and 75% necrotic cells at 0.2 and 1mmol/L hydrogen peroxide, respectively. The sensitizing effect was abolished by GSH-MEE. Inhibition of catalase or GPx significantly increased hydrogen peroxide-induced apoptosis, which was not reversed by GSH-MEE. Activated HSCs have increased ROS-detoxifying capacity compared to quiescent HSCs. Glutathione levels increase during HSC activation and protect against ROS-induced necrosis, whereas hydrogen peroxide-detoxifying enzymes protect against apoptotic cell death. © 2013.

Magnolol protects osteoblastic MC3T3-E1 cells against antimycin A-induced cytotoxicity through activation of mitochondrial function.

PubMed

Choi, Eun Mi

2012-06-01

Antimycin A treatment of cells blocks the mitochondrial electron transport chain and leads to elevated ROS generation. In the present study, we investigated the protective effects of magnolol, a hydroxylated biphenyl compound isolated from Magnolia officinalis, on antimycin A-induced toxicity in osteoblastic MC3T3-E1 cells. Osteoblastic MC3T3-E1 cells were pre-incubated with magnolol before treatment with antimycin A. Cell viability and mineralization of osteoblasts were assessed by MTT assay and Alizarin Red staining, respectively. Mitochondrial dysfunction in cells was measured by mitochondrial membrane potential (MMP), complex IV activity, and ATP level. The cellular antioxidant effect of magnolol in osteoblastic MC3T3-E1 cells was assessed by measuring cardiolipin oxidation, mitochondrial superoxide levels, and nitrotyrosine content. Phosphorylated cAMP-response element-binding protein (CREB ) was evaluated using ELISA assay. Pretreatment with magnolol prior to antimycin A exposure significantly reduced antimycin A-induced osteoblast dysfunction by preventing MMP dissipation, ATP loss, and CREB inactivation. Magnolol also reduced cardiolipin peroxidation, mitochondrial superoxide, and nitrotyrosine production induced by antimycin A. These results suggest that magnolol has a protective effect against antimycin A-induced cell damage by its antioxidant effects and the attenuation of mitochondrial dysfunction. All these data indicate that magnolol may reduce or prevent osteoblast degeneration in osteoporosis or other degenerative disorders.

Edaravone protects rats and human pulmonary alveolar epithelial cells against hyperoxia injury: heme oxygenase-1 and PI3K/Akt pathway may be involved.

PubMed

Cao, Huifang; Feng, Ying; Ning, Yunye; Zhang, Zinan; Li, Weihao; Li, Qiang

2015-01-01

Hyperoxic acute lung injury (HALI) is a clinical syndrome as a result of prolonged supplement of high concentrations of oxygen. As yet, no specific treatment is available for HALI. The present study aims to investigate the effects of edaravone on hyperoxia-induced oxidative injury and the underlying mechanism. We treated rats and human pulmonary alveolar epithelial cells with hyperoxia and different concentration of edaravone, then examined the effects of edaravone on cell viability, cell injury and two oxidative products. The roles of heme oxygenase-1 (HO-1) and PI3K/Akt pathway were explored using Western blot and corresponding inhibitors. The results showed that edaravone reduced lung biochemical alterations induced by hyperoxia and mortality of rats, dose-dependently alleviated cell mortality, cell injury, and peroxidation of cellular lipid and DNA oxidative damage. It upregulated cellular HO-1 expression and activity, which was reversed by PI3K/Akt pathway inhibition. The administration of zinc protoporphyrin-IX, a HO-1 inhibitor, and LY249002, a PI3K/Akt pathway inhibitor, abolished the protective effects of edaravone in cells. This study indicates that edaravone protects rats and human pulmonary alveolar epithelial cells against hyperoxia-induced injury and the antioxidant effect may be related to upregulation of HO-1, which is regulated by PI3K/Akt pathway.

Transduction of PEP-1-heme oxygenase-1 into insulin-producing INS-1 cells protects them against cytokine-induced cell death

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Su Jin; Kang, Hyung Kyung; Song, Dong Keun

Pro-inflammatory cytokines play a crucial role in the destruction of pancreatic β-cells, thereby triggering the development of autoimmune diabetes mellitus. We recently developed a cell-permeable fusion protein, PEP-1-heme oxygenase-1 (PEP-1-HO-1) and investigated the anti-inflammatory effects in macrophage cells. In this study, we transduced PEP-1-HO-1 into INS-1 insulinoma cells and examined its protective effect against cytokine-induced cell death. PEP-1-HO-1 was successfully delivered into INS-1 cells in time- and dose-dependent manner and was maintained within the cells for at least 48 h. Pre-treatment with PEP-1-HO-1 increased the survival of INS-1 cells exposed to cytokine mixture (IL-1β, IFN-γ, and TNF-α) in a dose-dependent manner.more » PEP-1-HO-1 markedly decreased cytokine-induced production of reactive oxygen species (ROS), nitric oxide (NO), and malondialdehyde (MDA). These protective effects of PEP-1-HO-1 against cytokines were correlated with the changes in the levels of signaling mediators of inflammation (iNOS and COX-2) and cell apoptosis/survival (Bcl-2, Bax, caspase-3, PARP, JNK, and Akt). These results showed that the transduced PEP-1-HO-1 efficiently prevented cytokine-induced cell death of INS-1 cells by alleviating oxidative/nitrosative stresses and inflammation. Further, these results suggested that PEP-1-mediated HO-1 transduction may be a potential therapeutic strategy to prevent β-cell destruction in patients with autoimmune diabetes mellitus. - Highlights: • We showed that PEP-1-HO-1 was efficiently delivered into INS-1 cells. • Transduced PEP-1-HO-1 exerted a protective effect against cytokine-induced cell death. • Transduced PEP-1-HO-1 inhibited cytokine-induced ROS and NO accumulation. • PEP-1-HO-1 suppressed cytokine-induced expression of iNOS, COX-2, and Bax. • PEP-1-HO-1 transduction may be an efficient tool to prevent β-cell destruction.« less

Type I interferon promotes alveolar epithelial type II cell survival during pulmonary Streptococcus pneumoniae infection and sterile lung injury in mice.

PubMed

Maier, Barbara B; Hladik, Anastasiya; Lakovits, Karin; Korosec, Ana; Martins, Rui; Kral, Julia B; Mesteri, Ildiko; Strobl, Birgit; Müller, Mathias; Kalinke, Ulrich; Merad, Miriam; Knapp, Sylvia

2016-09-01

Protecting the integrity of the lung epithelial barrier is essential to ensure respiration and proper oxygenation in patients suffering from various types of lung inflammation. Type I interferon (IFN-I) has been associated with pulmonary epithelial barrier function, however, the mechanisms and involved cell types remain unknown. We aimed to investigate the importance of IFN-I with respect to its epithelial barrier strengthening function to better understand immune-modulating effects in the lung with potential medical implications. Using a mouse model of pneumococcal pneumonia, we revealed that IFN-I selectively protects alveolar epithelial type II cells (AECII) from inflammation-induced cell death. Mechanistically, signaling via the IFN-I receptor on AECII is sufficient to promote AECII survival. The net effects of IFN-I are barrier protection, together with diminished tissue damage, inflammation, and bacterial loads. Importantly, we found that the protective role of IFN-I can also apply to sterile acute lung injury, in which loss of IFN-I signaling leads to a significant reduction in barrier function caused by AECII cell death. Our data suggest that IFN-I is an important mediator in lung inflammation that plays a protective role by antagonizing inflammation-associated cell obstruction, thereby strengthening the integrity of the epithelial barrier. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Drp1-dependent mitophagy protects against cisplatin-induced apoptosis of renal tubular epithelial cells by improving mitochondrial function

PubMed Central

Qi, Jia; Duan, Suyan; Huang, Zhimin; Zhang, Chengning; Wu, Lin; Zeng, Ming; Zhang, Bo; Wang, Ningning; Mao, Huijuan; Zhang, Aihua; Xing, Changying; Yuan, Yanggang

2017-01-01

Cisplatin chemotherapy often causes acute kidney injury (AKI) in cancer patients. There is increasing evidence that mitochondrial dysfunction plays an important role in cisplatin-induced nephrotoxicity. Degradation of damaged mitochondria is carried out by mitophagy. Although mitophagy is considered of particular importance in protecting against AKI, little is known of the precise role of mitophagy and its molecular mechanisms during cisplatin-induced nephrotoxicity. Also, evidence that activation of mitophagy improved mitochondrial function is lacking. Furthermore, several evidences have shown that mitochondrial fission coordinates with mitophagy. The aim of this study was to investigate whether activation of mitophagy protects against mitochondrial dysfunction and renal proximal tubular cells injury during cisplatin treatment. The effect of mitochondrial fission on mitophagy was also investigated. In cultured human renal proximal tubular cells, we observed that 3-methyladenine, a pharmacological inhibitor of autophagy, blocked mitophagy and exacerbated cisplatin-induced mitochondrial dysfunction and cells injury. In contrast, autophagy activator rapamycin enhanced mitophagy and protected against the harmful effects of cisplatin on mitochondrial function and cells viability. Suppression of mitochondrial fission by knockdown of its main regulator dynamin-related protein-1 (Drp1) decreased cisplatin-induced mitophagy. Meanwhile, Drp1 suppression protected against cisplatin-induced cells injury by inhibiting mitochondrial dysfunction. Our results provide evidence that Drp1-depedent mitophagy has potential as renoprotective targets for the treatment of cisplatin-induced AKI. PMID:28423497

Emulsions Made of Oils from Seeds of GM Flax Protect V79 Cells against Oxidative Stress

PubMed Central

Skorkowska-Telichowska, Katarzyna; Hasiewicz-Derkacz, Karolina; Gębarowski, Tomasz; Kulma, Anna; Kostyn, Kamil; Gębczak, Katarzyna; Szyjka, Anna; Wojtasik, Wioleta; Gąsiorowski, Kazimierz

2016-01-01

Polyunsaturated fatty acids, sterols, and hydrophilic phenolic compounds are components of flax oil that act as antioxidants. We investigated the impact of flax oil from transgenic flax in the form of emulsions on stressed Chinese hamster pulmonary fibroblasts. We found that the emulsions protect V79 cells against the H2O2 and the effect is dose dependent. They reduced the level of intracellular reactive oxygen species and protected genomic DNA against damage. The rate of cell proliferation increased upon treatment with the emulsions at a low concentration, while at a high concentration it decreased significantly, accompanied by increased frequency of apoptotic cell death. Expression analysis of selected genes revealed the upregulatory impact of the emulsions on the histones, acetylases, and deacetylases. Expression of apoptotic, proinflammatory, and anti-inflammatory genes was also altered. It is thus suggested that flax oil emulsions might be useful as a basis for biomedical products that actively protect cells against inflammation and degeneration. The beneficial effect on fibroblast resistance to oxidative damage was superior in the emulsion made of oil from transgenic plants which was correlated with the quantity of antioxidants and squalene. The emulsions from transgenic flax are promising candidates for skin protection against oxidative damage. PMID:26779302

Bacopa monnieri protects SH-SY5Y cells against tert-Butyl hydroperoxide-induced cell death via the ERK and PI3K pathways

PubMed Central

Petcharat, Kanoktip; Singh, Meharvan; Ingkaninan, Kornkanok; Attarat, Jongrak; Yasothornsrikul, Sukkid

2017-01-01

Objective Oxidative stress plays an important role in the pathological processes of various neurodegenerative diseases. Bacopa monnieri (BM) has a potent antioxidant property. Therefore, the purpose of this study was to evaluate the neuroprotective potential of BM against SH-SY5Y neuroblastoma cell death induced by the pro-oxidant insult, tert-Butyl hydroperoxide (TBHP), and to identify possible mechanisms related to its neuroprotective action. Methods The neuroprotective effect of BM was evaluated by the degree of protection against TBHP-induced cell death in human SH-SY5Y cells that was measured by calcein-AM assay. ERK1/2 and Akt phosphorylation was evaluated by immunoblotting. Results We found that BM exhibited protection against TBHP-mediated cytotoxicity. The neuroprotective effect of BM was abolished in the presence of either ERK1/2 or PI3K inhibitors. In addition, western blotting with anti-phospho-ERK1/2 and anti-phospho-Akt antibodies showed that BM increased both ERK1/2 and Akt phosphorylation. Conclusion These results suggest that BM by activation of ERK/MAPK and PI3K/Akt signaling pathways protects SH-SY5Y cells from TBHP-induced cell death. PMID:29152617

Protective effects of transduced Tat-DJ-1 protein against oxidative stress and ischemic brain injury.

PubMed

Jeong, Hoon Jae; Kim, Dae Won; Kim, Mi Jin; Woo, Su Jung; Kim, Hye Ri; Kim, So Mi; Jo, Hyo Sang; Hwang, Hyun Sook; Kim, Duk Soo; Cho, Sung Woo; Won, Moo Ho; Han, Kyu Hyung; Park, Jin Seu; Eum, Won Sik; Choi, Soo Young

2012-10-31

Reactive oxygen species (ROS) contribute to the development of a number of neuronal diseases including ischemia. DJ-1, also known to PARK7, plays an important role in transcriptional regulation, acting as molecular chaperone and antioxidant. In the present study, we investigated whether DJ-1 protein shows a protective effect against oxidative stress-induced neuronal cell death in vitro and in ischemic animal models in vivo. To explore DJ-1 protein's potential role in protecting against ischemic cell death, we constructed cell permeable Tat-DJ-1 fusion proteins. Tat-DJ-1 protein efficiently transduced into neuronal cells in a doseand time-dependent manner. Transduced Tat-DJ-1 protein increased cell survival against hydrogen peroxide (H2O2) toxicity and also reduced intracellular ROS. In addition, Tat-DJ-1 protein inhibited DNA fragmentation induced by H2O2. Furthermore, in animal models, immunohistochemical analysis revealed that Tat-DJ-1 protein prevented neuronal cell death induced by transient forebrain ischemia in the CA1 region of the hippocampus. These results demonstrate that transduced Tat-DJ-1 protein protects against cell death in vitro and in vivo, suggesting that the transduction of Tat-DJ-1 may be useful as a therapeutic agent for ischemic injuries related to oxidative stress.

Low-dose energetic protons induce adaptive and bystander effects that protect human cells against DNA damage caused by a subsequent exposure to energetic iron ions.

PubMed

Buonanno, Manuela; De Toledo, Sonia M; Howell, Roger W; Azzam, Edouard I

2015-05-01

During interplanetary missions, astronauts are exposed to mixed types of ionizing radiation. The low 'flux' of the high atomic number and high energy (HZE) radiations relative to the higher 'flux' of low linear energy transfer (LET) protons makes it highly probable that for any given cell in the body, proton events will precede any HZE event. Whereas progress has been made in our understanding of the biological effects of low-LET protons and high-LET HZE particles, the interplay between the biochemical processes modulated by these radiations is unclear. Here we show that exposure of normal human fibroblasts to a low mean absorbed dose of 20 cGy of 0.05 or 1-GeV protons (LET ∼ 1.25 or 0.2 keV/μm, respectively) protects the irradiated cells (P < 0.0001) against chromosomal damage induced by a subsequent exposure to a mean absorbed dose of 50 cGy from 1 GeV/u iron ions (LET ∼ 151 keV/μm). Surprisingly, unirradiated (i.e. bystander) cells with which the proton-irradiated cells were co-cultured were also significantly protected from the DNA-damaging effects of the challenge dose. The mitigating effect persisted for at least 24 h. These results highlight the interactions of biological effects due to direct cellular traversal by radiation with those due to bystander effects in cell populations exposed to mixed radiation fields. They show that protective adaptive responses can spread from cells targeted by low-LET space radiation to bystander cells in their vicinity. The findings are relevant to understanding the health hazards of space travel. © The Author 2015. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

Co-culture of clonal beta cells with GLP-1 and glucagon-secreting cell line impacts on beta cell insulin secretion, proliferation and susceptibility to cytotoxins.

PubMed

Green, Alastair D; Vasu, Srividya; Moffett, R Charlotte; Flatt, Peter R

2016-06-01

We investigated the direct effects on insulin releasing MIN6 cells of chronic exposure to GLP-1, glucagon or a combination of both peptides secreted from GLUTag L-cell and αTC1.9 alpha-cell lines in co-culture. MIN6, GLUTag and αTC1.9 cell lines exhibited high cellular hormone content and release of insulin, GLP-1 and glucagon, respectively. Co-culture of MIN6 cells with GLUTag cells significantly increased cellular insulin content, beta-cell proliferation, insulin secretory responses to a range of established secretogogues and afforded protection against exposure cytotoxic concentrations of glucose, lipid, streptozotocin or cytokines. Benefits of co-culture of MIN6 cells with αTC1.9 alphacells were limited to enhanced beta-cell proliferation with marginal positive actions on both insulin secretion and cellular protection. In contrast, co-culture of MIN6 with GLUTag cells plus αTC1.9 cells, markedly enhanced both insulin secretory responses and protection against beta-cell toxins compared with co-culture with GLUTag cells alone. These data indicate important long-term effects of conjoint GLP-1 and glucagon exposure on beta-cell function. This illustrates the possible functional significance of alpha-cell GLP-1 production as well as direct beneficial effects of dual agonism at beta-cell GLP-1 and glucagon receptors. Copyright © 2016 Elsevier B.V. and Société française de biochimie et biologie Moléculaire (SFBBM). All rights reserved.

The use of ebselen for radioprotection in cultured cells and mice.

PubMed

Tak, Jean Kyoung; Park, Jeen-Woo

2009-04-15

Ionizing radiation induces the production of reactive oxygen species (ROS), which play an important causative role in cell death. Therefore, compounds that control the level of ROS may confer radioprotective effects. Ebselen, a seleno-organic compound, has been shown to protect against cell injury caused by ROS. The objective of this study was to examine the effects of ebselen on radiation-dependent toxicity. We investigated the protective role of ebselen against ionizing radiation in U937 cells and mice. Upon exposure to 20 Gy of gamma-irradiation, there was a distinct difference between untreated cells and the cells pretreated with 5 microM ebselen for 2 h with respect to viability, cellular redox status, and oxidative damage to cells. When cells were exposed to 2 Gy of gamma-irradiation, there was a distinct difference between the untreated cells and the cells pretreated with ebselen with respect to apoptotic features and mitochondrial function. Ebselen administration for 14 days at a daily dosage of 10 mg/kg provided substantial protection against killing and oxidative damage to mice exposed to whole-body irradiation. These data indicate that ebselen may have great potential as a new class of in vivo, non-sulfur-containing radiation protector.

Cyanidin-3-O-Glucoside Modulates the In Vitro Inflammatory Crosstalk between Intestinal Epithelial and Endothelial Cells.

PubMed

Ferrari, Daniela; Cimino, Francesco; Fratantonio, Deborah; Molonia, Maria Sofia; Bashllari, Romina; Busà, Rossana; Saija, Antonella; Speciale, Antonio

2017-01-01

Intestinal epithelium represents a protective physical barrier and actively contributes to the mucosal immune system. Polarized basolateral intestinal secretion of inflammatory mediators, followed by activation of NF- κ B signaling and inflammatory pathways in endothelial cells, efficiently triggers extravasation of neutrophils from the vasculature, therefore contributing to the development and maintenance of intestinal inflammation. Proper regulation of NF- κ B activation at the epithelial interface is crucial for the maintenance of physiological tissue homeostasis. Many papers reported that anthocyanins, a group of compounds belonging to flavonoids, possess anti-inflammatory effects and modulate NF- κ B activity. In this study, by using a coculture in vitro system, we aimed to evaluate the effects of TNF- α -stimulated intestinal cells on endothelial cells activation, as well as the protective effects of cyanidin-3-glucoside (C3G). In this model, TNF- α induced nuclear translocation of NF- κ B and TNF- α and IL-8 gene expression in Caco-2 cells, whereas C3G pretreatment dose-dependently reduced these effects. Furthermore, TNF- α -stimulated Caco-2 cells induced endothelial cells activation with increased E-selectin and VCAM-1 mRNA, leukocyte adhesion, and NF- κ B levels in HUVECs, which were inhibited by C3G. We demonstrated that selective inhibition of the NF- κ B pathway in epithelial cells represents the main mechanism by which C3G exerts these protective effects. Thus, anthocyanins could contribute to the management of chronic gut inflammatory diseases.

Influence of various scavengers of •OH radicals on the radiation sensitivity of yeast and bacteria.

PubMed

Múčka, Viliam; Bláha, Pavel; Čuba, Václav; Červenák, Jaroslav

2013-12-01

To quantitatively investigate the influence of various •OH (hydroxyl radical) scavengers on the radiation sensitivity of yeast and bacteria, particularly to define the relationship between the protective effect of a scavenger and its •OH scavenging efficiency. In order to study the protective effect of •OH scavengers we used various concentrations of four scavengers (methanol, potassium formate, ethanol and ascorbic acid) in isotonic salt solutions. These solutions containing live yeast (Saccharomyces cerevisiae) or bacteria (Escherichia coli) were irradiated with (60)Co isotope γ -radiation using two different doses and dose rates. The number of surviving cells was determined prior to and after irradiation both in suspension with and without scavengers. The surviving fractions after irradiation with and without the scavenger were evaluated. The main results of the paper were: The surviving fraction increased approximately linearly within the measured interval with increasing concentration of the scavenger. The same dependences were found for the protecting effect depending on the scavenging efficiency. The slopes of these dependences (k) were found to be characteristic for each scavenger. The k value determined the degree in which the scavenging of •OH radicals participated in the protection of living cells. The protective effects of scavengers at the same scavenging efficiency were different and unique for each scavenger. No simple relation was found between the efficiency of scavenger k and the rate constant kOH of the reactions between scavengers and •OH radicals. Our results suggest that the studied scavengers effectively protected yeast and bacteria against ionizing radiation. Although the scavenging of •OH radicals seems to be important for protection of living cells, it is clearly not the only process on which the protection is based.

Predominant Occupation of the Class I MHC Molecule H-2Kwm7 with a Single Self-peptide Suggests a Mechanism for its Diabetes-protective Effect

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brims, D.; Qian, J; Jarchum, I

2010-01-01

Type 1 diabetes (T1D) is an autoimmune disease characterized by T cell-mediated destruction of insulin-producing pancreatic {beta} cells. In both humans and the non-obese diabetic (NOD) mouse model of T1D, class II MHC alleles are the primary determinant of disease susceptibility. However, class I MHC genes also influence risk. These findings are consistent with the requirement for both CD{sup 4+} and CD{sup 8+} T cells in the pathogenesis of T1D. Although a large body of work has permitted the identification of multiple mechanisms to explain the diabetes-protective effect of particular class II MHC alleles, studies examining the protective influence ofmore » class I alleles are lacking. Here, we explored this question by performing biochemical and structural analyses of the murine class I MHC molecule H-2K{sup wm7}, which exerts a diabetes-protective effect in NOD mice. We have found that H-2K{sup wm7} molecules are predominantly occupied by the single self-peptide VNDIFERI, derived from the ubiquitous protein histone H2B. This unexpected finding suggests that the inability of H-2K{sup wm7} to support T1D development could be due, at least in part, to the failure of peptides from critical {beta}-cell antigens to adequately compete for binding and be presented to T cells. Predominant presentation of a single peptide would also be expected to influence T-cell selection, potentially leading to a reduced ability to select a diabetogenic CD{sup 8+} T-cell repertoire. The report that one of the predominant peptides bound by T1D-protective HLA-A*31 is histone derived suggests the potential translation of our findings to human diabetes-protective class I MHC molecules.« less

Orally Administered Salacia reticulata Extract Reduces H1N1 Influenza Clinical Symptoms in Murine Lung Tissues Putatively Due to Enhanced Natural Killer Cell Activity

PubMed Central

Romero-Pérez, Gustavo A.; Egashira, Masayo; Harada, Yuri; Tsuruta, Takeshi; Oda, Yuriko; Ueda, Fumitaka; Tsukahara, Takamitsu; Tsukamoto, Yasuhiro; Inoue, Ryo

2016-01-01

Influenza is a major cause of respiratory tract infection. Although most cases do not require further hospitalization, influenza periodically causes epidemics in humans that can potentially infect and kill millions of people. To countermeasure this threat, new vaccines need to be developed annually to match emerging influenza viral strains with increased resistance to existing vaccines. Thus, there is a need for finding and developing new anti-influenza viral agents as alternatives to current treatments. Here, we tested the antiviral effects of an extract from the stems and roots of Salacia reticulata (SSRE), a plant rich in phytochemicals, such as salacinol, kotalanol, and catechins, on H1N1 influenza virus-infected mice. Following oral administration of 0.6 mg/day of SSRE, the incidence of coughing decreased in 80% of mice, and only one case of severe pulmonary inflammation was detected. Moreover, when compared with mice given Lactobacillus casei JCM1134, a strain previously shown to help increase in vitro natural killer (NK) cell activity, SSRE-administered mice showed greater and equal NK cell activity in splenocytes and pulmonary cells, respectively, at high effector cell:target cell ratios. Next, to test whether or not SSRE would exert protective effects against influenza in the absence of gut microbiota, mice were given antibiotics before being inoculated influenza virus and subsequently administered SSRE. SSRE administration induced an increase in NK cell activity in splenocytes and pulmonary cells at levels similar to those detected in mice not treated with antibiotics. Based on our results, it can be concluded that phytochemicals in the SSRE exerted protective effects against influenza infection putatively via modulation of the immune response, including enhancement of NK cell activity, although some protective effects were not necessarily through modulation of gut microbiota. Further investigation is necessary to elucidate the molecular mechanisms underlying the protective effects of SSRE against influenza infection. PMID:27066007

Wild Raspberry Subjected to Simulated Gastrointestinal Digestion Improves the Protective Capacity against Ethyl Carbamate-Induced Oxidative Damage in Caco-2 Cells

PubMed Central

Chen, Wei; Xu, Yang; Zhang, Lingxia; Li, Ya; Zheng, Xiaodong

2016-01-01

Ethyl carbamate (EC), a probable human carcinogen, occurs widely in many fermented foods. Previous studies indicated that EC-induced cytotoxicity was associated with oxidative stress. Wild raspberries are rich in polyphenolic compounds, which possess potent antioxidant activity. This study was conducted to investigate the protective effect of wild raspberry extracts produced before (RE) and after in vitro simulated gastrointestinal digestion (RD) on EC-induced oxidative damage in Caco-2 cells. Our primary data showed that ethyl carbamate could result in cytotoxicity and genotoxicity in Caco-2 cells and raspberry extract after digestion (RD) may be more effective than that before digestion (RE) in attenuating toxicity caused by ethyl carbamate. Further investigation by fluorescence microscope revealed that RD may significantly ameliorate EC-induced oxidative damage by scavenging the overproduction of intracellular reactive oxygen species (ROS), maintaining mitochondrial function and preventing glutathione (GSH) depletion. In addition, HPLC-ESI-MS results showed that the contents of identified polyphenolic compounds (esculin, kaempferol O-hexoside, and pelargonidin O-hexoside) were remarkably increased after digestion, which might be related to the better protective effect of RD. Overall, our results demonstrated that raspberry extract undergoing simulated gastrointestinal digestion may improve the protective effect against EC-induced oxidative damage in Caco-2 cells. PMID:26788245

EGb 761 Protects Cardiac Microvascular Endothelial Cells against Hypoxia/Reoxygenation Injury and Exerts Inhibitory Effect on the ATM Pathway.

PubMed

Zhang, Chao; Wang, Deng-Feng; Zhang, Zhuang; Han, Dong; Yang, Kan

2017-03-28

Ginkgo bilob a extract (EGb 761) has been widely used clinically to reduce myocardial ischemia reperfusion injury (MIRI). Microvascular endothelial cells (MVECs) may be a proper cellular model in vitro for the effect and mechanism study against MIRI. However, the protective effect of EGb 761 on MVECs resisting hypoxia/reoxygenation (H/R) injury is little reported. In this study, H/R-injured MVECs were treated with EGb 761, and then the cell viability, apoptosis, ROS production, SOD activity, caspase-3 activity, and protein level of ATM, γ-H2AX, p53, and Bax were measured. ATM siRNA was transfected to study the changes of protein in the ATM pathway. EGb 761 presented protective effect on H/R-injured MVECs, with decreasing cell death, apoptosis, and ROS, and elevated SOD activity. Next, EGb 761 could inhibit H/R-induced ATM, γ-H2AX, p53, and Bax in a dose-dependent manner. Moreover, ATM siRNA also could inhibit H/R-induced ATM, γ-H2AX, p53, and Bax. Overall, these findings verify that EGb 761 protects cardiac MVECs from H/R injury, and for the first time, illustrate the influence on the ATM pathway and apoptosis by EGb 761 via dampening ROS.

Protective effects of HemoHIM on immune and hematopoietic systems against γ-irradiation.

PubMed

Park, Hae-Ran; Jo, Sung-Kee; Jung, Uhee; Yee, Sung-Tae; Kim, Sung-Ho

2014-02-01

We examined the effect of HemoHIM on the protective efficacy of hematopoietic stem cells and on the recovery of immune cells against sublethal doses of ionizing radiation. Two-month-old mice were exposed to γ-rays at a dose of 8, 6.5, or 5 Gy for a30-day survival study, endogenous spleen colony formation, or other experiments, respectively. HemoHIM was injected intraperitoneally before and after irradiation. Our results showed that HemoHIM significantly decreased the mortality of sublethally irradiated mice. The HemoHIM administration decreased the apoptosis of bone marrow cells in irradiated mice. On the other hand, HemoHIM increased the formation of endogenous spleen colony in irradiated mice. In irradiated mice, the recovery of total leukocytes in the peripheral blood and lymphocytes in the spleen were enhanced significantly by HemoHIM. Moreover, the function of B cells, T cells, and NK cells regenerated in irradiated mice were significantly improved by the administration of HemoHIM. HemoHIM showed an ideal radioprotector for protecting hematopoietic stem cells and for accelerating the recovery of immune cells. We propose HemoHIM as a beneficial supplement drug during radiotherapy to alleviate adverse radiation-induced effects for cancer patients. Copyright © 2013 John Wiley & Sons, Ltd.

Corrosion Protection of Al/Au/ZnO Anode for Hybrid Cell Application

PubMed Central

Slaughter, Gymama; Stevens, Brian

2015-01-01

Effective protection of power sources from corrosion is critical in the development of abiotic fuel cells, biofuel cells, hybrid cells and biobateries for implantable bioelectronics. Corrosion of these bioelectronic devices result in device inability to generate bioelectricity. In this paper Al/Au/ZnO was considered as a possible anodic substrate for the development of a hybrid cell. The protective abilities of corrosive resistant aluminum hydroxide and zinc phosphite composite films formed on the surface of Al/Au/ZnO anode in various electrolyte environments were examined by electrochemical methods. The presence of phosphate buffer and physiological saline (NaCl) buffer allows for the formation of aluminum hyrdroxide and zinc phosphite composite films on the surface of the Al/Au/ZnO anode that prevent further corrosion of the anode. The highly protective films formed on the Al/Au/ZnO anode during energy harvesting in a physiological saline environment resulted in 98.5% corrosion protective efficiency, thereby demonstrating that the formation of aluminum hydroxide and zinc phosphite composite films are effective in the prevention of anode corrosion during energy harvesting. A cell assembly consisting of the Al/Au/ZnO anode and platinum cathode resulted in an open circuit voltage of 1.03 V. A maximum power density of 955.3 μW/ cm2 in physiological saline buffer at a cell voltage and current density of 345 mV and 2.89 mA/ cm2, respectively. PMID:26580661

Corrosion Protection of Al/Au/ZnO Anode for Hybrid Cell Application.

PubMed

Slaughter, Gymama; Stevens, Brian

2015-11-16

Effective protection of power sources from corrosion is critical in the development of abiotic fuel cells, biofuel cells, hybrid cells and biobateries for implantable bioelectronics. Corrosion of these bioelectronic devices result in device inability to generate bioelectricity. In this paper Al/Au/ZnO was considered as a possible anodic substrate for the development of a hybrid cell. The protective abilities of corrosive resistant aluminum hydroxide and zinc phosphite composite films formed on the surface of Al/Au/ZnO anode in various electrolyte environments were examined by electrochemical methods. The presence of phosphate buffer and physiological saline (NaCl) buffer allows for the formation of aluminum hyrdroxide and zinc phosphite composite films on the surface of the Al/Au/ZnO anode that prevent further corrosion of the anode. The highly protective films formed on the Al/Au/ZnO anode during energy harvesting in a physiological saline environment resulted in 98.5% corrosion protective efficiency, thereby demonstrating that the formation of aluminum hydroxide and zinc phosphite composite films are effective in the prevention of anode corrosion during energy harvesting. A cell assembly consisting of the Al/Au/ZnO anode and platinum cathode resulted in an open circuit voltage of 1.03 V. A maximum power density of 955.3 mW/ cm² in physiological saline buffer at a cell voltage and current density of 345 mV and 2.89 mA/ cm², respectively.

Eriodictyol protects against H(2)O(2)-induced neuron-like PC12 cell death through activation of Nrf2/ARE signaling pathway.

PubMed

Lou, Haiyan; Jing, Xu; Ren, Dongmei; Wei, Xinbing; Zhang, Xiumei

2012-07-01

Eriodictyol, a flavonoid isolated from the Chinese herb Dracocephalum rupestre has long been established as an antioxidant. The present study was designed to explore the protective effects of eriodictyol against hydrogen peroxide (H(2)O(2))-induced neurotoxicity with cultured rat pheochromocytoma cells (PC12 cells) and the possible mechanisms involved. For this purpose, differentiated PC12 cells were cultured and exposed to 200 μM H(2)O(2) in the absence or presence of eriodictyol (20, 40 and 80 μM). In addition, the potential contribution of the Nrf2/ARE neuroprotective pathway in eriodictyol-mediated protection against H(2)O(2)-induced neurotoxicity was also investigated. The results showed that H(2)O(2)-induced cell death can be inhibited in the presence of eriodictyol as measured by assays for MTT and apoptosis. Further study revealed that eriodictyol induced the nuclear translocation of Nrf2, enhanced the expression of heme oxygenase (HO-1) and γ-glutamylcysteine synthetase (γ-GCS), and increased the levels of intracellular glutathione. Treatment of PC12 cells with Nrf2 small interference RNA abolished eriodictyol-induced HO-1 and γ-GCS expression and its protective effects. In conclusion, these results suggest that eriodictyol upregulates HO-1 and γ-GCS expression through the activation of Nrf2/ARE pathway and protects PC12 cells against H(2)O(2)-induced oxidative stress. Copyright © 2012 Elsevier Ltd. All rights reserved.

Protective effects of nicergoline against hydrogen peroxide toxicity in rat neuronal cell line.

PubMed

Iwata, E; Miyazaki, I; Asanuma, M; Iida, A; Ogawa, N

1998-07-17

We examined the effects of nicergoline on hydrogen peroxide (H2O2)-induced neurotoxicity in cultured rat neuronal cell line (B50). H2O2 induced death of B50 cells in a dose-dependent manner. The H2O2-induced neuronal cell death was significantly decreased in B50 cells maintained in the presence of nicergoline. We compared the levels of antioxidants (glutathione, catalase and superoxide dismutase) in nicergoline-treated and untreated B50 cells. Lipid peroxidation products (thiobarbituric acid reactive substances, TBARS) levels were also measured. Cultures treated with nicergoline had higher levels of catalase activity. TBARS level was significantly lower in nicergoline-treated cells than in untreated cells. Our results suggest that nicergoline may induce the up-regulation of intracellular antioxidant defences and protect the neuronal cells against oxidative stress.

Antioxidants in Photosynthesis and Human Nutrition

NASA Astrophysics Data System (ADS)

Demmig-Adams, Barbara; Adams, William W.

2002-12-01

The harnessing of solar energy by photosynthesis depends on a safety valve that effectively eliminates hazardous excess energy and prevents oxidative damage to the plant cells. Many of the compounds that protect plant cells also protect human cells. Improving plant resistance to stress may thus have the beneficial side effect of also improving the nutritional quality of plants in the human diet. The pathways that synthesize these compounds are becoming amenable to genetic manipulation, which may yield benefits as widespread as improved plant stress tolerance and improved human physical and mental health.

The protective effects of bilberry and lingonberry extracts against UV light-induced retinal photoreceptor cell damage in vitro.

PubMed

Ogawa, Kenjirou; Tsuruma, Kazuhiro; Tanaka, Junji; Kakino, Mamoru; Kobayashi, Saori; Shimazawa, Masamitsu; Hara, Hideaki

2013-10-30

Bilberry extract (B-ext) and lingonberry extract (L-ext) are currently used as health supplements. We investigated the protective mechanisms of the B-ext and L-ext against ultraviolet A (UVA)-induced retinal photoreceptor cell damage. Cultured murine photoreceptor (661W) cells were exposed to UVA following treatment with B-ext and L-ext and their main constituents (cyanidin, delphinidin, malvidin, trans-resveratrol, and procyanidin). B-ext, L-ext, and constituents improved cell viability and suppressed ROS generation. Phosphorylation of p38 mitogen-activated protein kinase (p38 MAPK), c-Jun N-terminal kinase (JNK), and protein kinase B (Akt) were analyzed by Western blotting. B-ext and cyanidin inhibited phosphorylation of p38 MAPK, and B-ext also inhibited phosphorylation of JNK by UVA. L-ext, trans-resveratrol, and procyanidin alleviated the reduction of phosphorylated Akt levels by UVA. Finally, a cotreatment with B-ext and L-ext showed an additive effect on cell viability. Our findings suggest that both B-ext and L-ext endow protective effects against UVA-induced retinal damage.

Hormonal Contraceptives Differentially Suppress TFV and TAF Inhibition of HIV Infection and TFV-DP in Blood and Genital Tract CD4+ T cells.

PubMed

Shen, Zheng; Rodriguez-Garcia, Marta; Patel, Mickey V; Bodwell, Jack; Kashuba, Angela D M; Wira, Charles R

2017-12-18

HIV prevention research is focused on combining antiretrovirals (ARV) and progestin contraceptives to prevent HIV infection and pregnancy. The possibility that progestins compromise ARV anti-HIV activity prompted us to evaluate the effects of progestins on tenofovir (TFV) and TFV-alafenamide (TAF) on HIV infection and intracellular TFV-diphosphate (TFV-DP) concentrations in blood and genital CD4+ T cells. Following incubation of blood CD4+ T cells with TFV or TAF, Medroxyprogesterone acetate (MPA), but not Levonorgestrel, Norethisterone or progesterone, suppressed the anti-HIV effect of TFV by reducing intracellular TFV-DP, but had no effect on TAF inhibition of infection or TFV-DP. In contrast, with genital CD4+ T cells, MPA suppressed TAF inhibition of HIV infection and lowered of TFV-DP concentrations without affecting TFV protection. These findings demonstrate that MPA selectively compromises TFV and TAF protection in blood and genital CD4+ T cells and suggests that MPA may decrease ARV protection in individuals who use ARV intermittently for prevention.

Neuroprotective effects of SB-415286 on hydrogen peroxide-induced cell death in B65 rat neuroblastoma cells and neurons.

PubMed

Pizarro, Javier G; Yeste-Velasco, Marc; Rimbau, Victor; Casadesús, Gemma; Smith, Mark A; Pallàs, Mercè; Folch, Jaume; Camins, Antoni

2008-01-01

Glycogen synthase kinase-3 (GSK-3) is involved in the pathogenesis of several neurodegenerative diseases. In addition, as oxidative stress has been implicated in all neurodegenerative disorders, the inhibition of both pathways offers a potential strategy for preventing or delaying neurodegeneration. We examined the cytoprotective effects of lithium and SB-415286, two inhibitors of GSK-3, using a rat B65 cell line and also in cerebellar granule cells (CGN). H(2)O(2) decreased the inactive form of GSK-3 (phospho-GSK-3 at Ser9), as measured by immunoblot experiments involving an antibody against the inactive form of the enzyme. Moreover, lithium inhibited this effect. While SB-415286 exerted a protective effect, lithium did not attenuate the toxic effects of H(2)O(2) (1mM). We then examined those mechanisms implicated in the protective effects of SB-415286. When we analyzed reactive oxygen species (ROS) production using the fluorescent probe 2,7-dichlorodihydrofluorescein diacetate in B65 cells, as well as in CGN, we found that SB-415286 strongly reduced DCF fluorescence. Lithium, however, did not exhibit any antioxidant properties. We conclude that the GSK-3 inhibitor SB-415286 has antioxidant properties, which may explain the cytoprotective effects against H(2)O(2) damage. Furthermore, inhibition of GSK-3 activity was not involved in this protective effect.

Cellular Self-Defense: How Cell-Autonomous Immunity Protects Against Pathogens

PubMed Central

Randow, Felix; MacMicking, John D.; James, Leo C.

2013-01-01

Our prevailing view of vertebrate host defense is strongly shaped by the notion of a specialized set of immune cells as sole guardians of antimicrobial resistance. Yet this view greatly underestimates a capacity for most cell lineages—the majority of which fall outside the traditional province of the immune system—to defend themselves against infection. This ancient and ubiquitous form of host protection is termed cell-autonomous immunity and operates across all three domains of life. Here, we discuss the organizing principles that govern cellular self-defense and how intracellular compartmentalization has shaped its activities to provide effective protection against a wide variety of microbial pathogens. PMID:23661752

Cellular self-defense: how cell-autonomous immunity protects against pathogens.

PubMed

Randow, Felix; MacMicking, John D; James, Leo C

2013-05-10

Our prevailing view of vertebrate host defense is strongly shaped by the notion of a specialized set of immune cells as sole guardians of antimicrobial resistance. Yet this view greatly underestimates a capacity for most cell lineages-the majority of which fall outside the traditional province of the immune system-to defend themselves against infection. This ancient and ubiquitous form of host protection is termed cell-autonomous immunity and operates across all three domains of life. Here, we discuss the organizing principles that govern cellular self-defense and how intracellular compartmentalization has shaped its activities to provide effective protection against a wide variety of microbial pathogens.

Cerium oxide nanoparticles protect endothelial cells from apoptosis induced by oxidative stress.

PubMed

Chen, Shizhu; Hou, Yingjian; Cheng, Gong; Zhang, Cuimiao; Wang, Shuxiang; Zhang, Jinchao

2013-07-01

Oxidative stress is well documented to cause injury to endothelial cells (ECs), which in turn trigger cardiovascular diseases. Previous studies revealed that cerium oxide nanoparticles (nanoceria) had antioxidant property, but the protective effect of nanoceria on ROS injury to ECs and cardiovascular diseases has not been reported. In the current study, we investigated the protective effect and underlying mechanisms of nanoceria on oxidative injury to ECs. The cell viability, lactate dehydrogenase release, cellular uptake, intracellular localization and reactive oxygen species (ROS) levels, endocytosis mechanism, cell apoptosis, and mitochondrial membrane potential were performed. The results indicated that nanoceria had no cytotoxicity on ECs but had the ability to prevent injury by H2O2. Nanoceria could be uptaken into ECs through caveolae- and clathrin-mediated endocytosis and distributed throughout the cytoplasma. The internalized nanoceria effectively attenuated ROS overproduction induced by H2O2. Apoptosis was also alleviated greatly by nanoceria pretreatment. These results may be helpful for more rational application of nanoceria in biomedical fields in the future.

Cardiovascular protection of magnolol: cell-type specificity and dose-related effects

PubMed Central

2012-01-01

Magnolia officinalis has been widely used in traditional Chinese medicine. Magnolol, an active component isolated from Magnolia officinalis, is known to be a cardiovascular protector since 1994. The multiplex mechanisms of magnolol on cardiovascular protection depends on cell types and dosages, and will be reviewed and discussed in this article. Magnolol under low and moderate dosage possesses the ability to protect heart from ischemic/reperfusion injury, reduces atherosclerotic change, protects endothelial cell against apoptosis and inhibits neutrophil-endothelial adhesion. The moderate to high concentration of magnolol mainly acts on smooth muscle cells and platelets. Magnolol induces apoptosis in vascular smooth muscle cells at moderate concentration and inhibits proliferation at moderate and high concentration. High concentration of magnolol also abrogates platelet activation, aggregation and thrombus formation. Magnolol also serves as an smooth muscle relaxant only upon the high concentration. Oral intake of magnolol to reach the therapeutic level for cardiovascular protection is applicable, thus makes magnolol an agent of great potential for preventing cardiovascular diseases in high-risk patients. PMID:22849814

Cardiovascular protection of magnolol: cell-type specificity and dose-related effects.

PubMed

Ho, Jennifer Hui-Chun; Hong, Chuang-Ye

2012-07-31

Magnolia officinalis has been widely used in traditional Chinese medicine. Magnolol, an active component isolated from Magnolia officinalis, is known to be a cardiovascular protector since 1994. The multiplex mechanisms of magnolol on cardiovascular protection depends on cell types and dosages, and will be reviewed and discussed in this article. Magnolol under low and moderate dosage possesses the ability to protect heart from ischemic/reperfusion injury, reduces atherosclerotic change, protects endothelial cell against apoptosis and inhibits neutrophil-endothelial adhesion. The moderate to high concentration of magnolol mainly acts on smooth muscle cells and platelets. Magnolol induces apoptosis in vascular smooth muscle cells at moderate concentration and inhibits proliferation at moderate and high concentration. High concentration of magnolol also abrogates platelet activation, aggregation and thrombus formation. Magnolol also serves as an smooth muscle relaxant only upon the high concentration. Oral intake of magnolol to reach the therapeutic level for cardiovascular protection is applicable, thus makes magnolol an agent of great potential for preventing cardiovascular diseases in high-risk patients.

Costimulatory Effects of an Immunodominant Parasite Antigen Paradoxically Prevent Induction of Optimal CD8 T Cell Protective Immunity.

PubMed

Eickhoff, Christopher S; Zhang, Xiuli; Vasconcelos, Jose R; Motz, R Geoffrey; Sullivan, Nicole L; O'Shea, Kelly; Pozzi, Nicola; Gohara, David W; Blase, Jennifer R; Di Cera, Enrico; Hoft, Daniel F

2016-09-01

Trypanosoma cruzi infection is controlled but not eliminated by host immunity. The T. cruzi trans-sialidase (TS) gene superfamily encodes immunodominant protective antigens, but expression of altered peptide ligands by different TS genes has been hypothesized to promote immunoevasion. We molecularly defined TS epitopes to determine their importance for protection versus parasite persistence. Peptide-pulsed dendritic cell vaccination experiments demonstrated that one pair of immunodominant CD4+ and CD8+ TS peptides alone can induce protective immunity (100% survival post-lethal parasite challenge). TS DNA vaccines have been shown by us (and others) to protect BALB/c mice against T. cruzi challenge. We generated a new TS vaccine in which the immunodominant TS CD8+ epitope MHC anchoring positions were mutated, rendering the mutant TS vaccine incapable of inducing immunity to the immunodominant CD8 epitope. Immunization of mice with wild type (WT) and mutant TS vaccines demonstrated that vaccines encoding enzymatically active protein and the immunodominant CD8+ T cell epitope enhance subdominant pathogen-specific CD8+ T cell responses. More specifically, CD8+ T cells from WT TS DNA vaccinated mice were responsive to 14 predicted CD8+ TS epitopes, while T cells from mutant TS DNA vaccinated mice were responsive to just one of these 14 predicted TS epitopes. Molecular and structural biology studies revealed that this novel costimulatory mechanism involves CD45 signaling triggered by enzymatically active TS. This enhancing effect on subdominant T cells negatively regulates protective immunity. Using peptide-pulsed DC vaccination experiments, we have shown that vaccines inducing both immunodominant and subdominant epitope responses were significantly less protective than vaccines inducing only immunodominant-specific responses. These results have important implications for T. cruzi vaccine development. Of broader significance, we demonstrate that increasing breadth of T cell epitope responses induced by vaccination is not always advantageous for host immunity.

Oral Escherichia coli Colonization Factor Antigen I (CFA/I) Fimbriae Ameliorate Arthritis via IL-35, not IL-27

PubMed Central

Kochetkova, Irina; Thornburg, Theresa; Callis, Gayle; Holderness, Kathryn; Maddaloni, Massimo; Pascual, David W.

2014-01-01

A Salmonella therapeutic expressing enterotoxigenic E. coli colonization factor antigen I (CFA/I) fimbriae protects against collagen-induced arthritis (CIA) by eliciting two regulatory T cell (Treg) subsets: TGF-β-producing Foxp3−CD39+CD4+ and IL-10-producing Foxp3+CD39+CD4+ T cells. However, it is unclear if CFA/I fimbriae alone are protective, and if other regulatory cytokines are involved especially in the context for the EBI3-sharing cytokines, Treg-derived IL-35 and APC-derived IL-27, both capable of suppressing Th17 cells and regulating autoimmune diseases. Subsequent evaluation revealed that a single oral dose of purified, soluble CFA/I fimbriae protected against CIA as effectively as Salmonella-CFA/I, and found Foxp3+CD39+CD4+ T cells as the source of secreted IL-35, whereas IL-27 production by CD11c+ cells was inhibited. Inquiring into their relevance, CFA/I fimbriae-treated IL-27 receptor-deficient (WSX-1−/−) mice were equally protected against CIA as wild-type mice suggesting a limited role for IL-27. In contrast, CFA/I fimbriae-mediated protection was abated in EBI3−/− mice accompanied by the loss of TGF-β- and IL-10-producing Tregs. Adoptive transfer of B6 CD39+CD4+ T cells to EBI3−/− mice with concurrent CFA/I plus IL-35 treatment effectively stimulated Tregs suppressing proinflammatory CII-specific Th cells. Opposingly, recipients co-transferred with B6 and EBI3−/− CD39+CD4+ T cells and treated with CFA/I plus IL-35 failed in protecting mice implicating the importance for endogenous IL-35 to confer CFA/I-mediated protection. Thus, CFA/I fimbriae stimulate IL-35 required for the co-induction of TGF-β and IL-10. PMID:24337375

Immunological Signatures after Bordetella pertussis Infection Demonstrate Importance of Pulmonary Innate Immune Cells

PubMed Central

Brummelman, Jolanda; van der Maas, Larissa; Tilstra, Wichard; Pennings, Jeroen L. A.; Han, Wanda G. H.; van Els, Cécile A. C. M.; van Riet, Elly; Kersten, Gideon F. A.; Metz, Bernard

2016-01-01

Effective immunity against Bordetella pertussis is currently under discussion following the stacking evidence of pertussis resurgence in the vaccinated population. Natural immunity is more effective than vaccine-induced immunity indicating that knowledge on infection-induced responses may contribute to improve vaccination strategies. We applied a systems biology approach comprising microarray, flow cytometry and multiplex immunoassays to unravel the molecular and cellular signatures in unprotected mice and protected mice with infection-induced immunity, around a B. pertussis challenge. Pre-existing systemic memory Th1/Th17 cells, memory B-cells, and mucosal IgA specific for Ptx, Vag8, Fim2/3 were detected in the protected mice 56 days after an experimental infection. In addition, pre-existing high activity and reactivation of pulmonary innate cells such as alveolar macrophages, M-cells and goblet cells was detected. The pro-inflammatory responses in the lungs and serum, and neutrophil recruitment in the spleen upon an infectious challenge of unprotected mice were absent in protected mice. Instead, fast pulmonary immune responses in protected mice led to efficient bacterial clearance and harbored potential new gene markers that contribute to immunity against B. pertussis. These responses comprised of innate makers, such as Clca3, Retlna, Glycam1, Gp2, and Umod, next to adaptive markers, such as CCR6+ B-cells, CCR6+ Th17 cells and CXCR6+ T-cells as demonstrated by transcriptome analysis. In conclusion, besides effective Th1/Th17 and mucosal IgA responses, the primary infection-induced immunity benefits from activation of pulmonary resident innate immune cells, achieved by local pathogen-recognition. These molecular signatures of primary infection-induced immunity provided potential markers to improve vaccine-induced immunity against B. pertussis. PMID:27711188

Isothiocyanate from Moringa oleifera seeds mitigates hydrogen peroxide-induced cytotoxicity and preserved morphological features of human neuronal cells

PubMed Central

Shaari, Khozirah; Rosli, Rozita

2018-01-01

Reactive oxygen species are well known for induction of oxidative stress conditions through oxidation of vital biomarkers leading to cellular death via apoptosis and other process, thereby causing devastative effects on the host organs. This effect is believed to be linked with pathological alterations seen in several neurodegenerative disease conditions. Many phytochemical compounds proved to have robust antioxidant activities that deterred cells against cytotoxic stress environment, thus protect apoptotic cell death. In view of that we studied the potential of glucomoringin-isothiocyanate (GMG-ITC) or moringin to mitigate the process that lead to neurodegeneration in various ways. Neuroprotective effect of GMG-ITC was performed on retinoic acid (RA) induced differentiated neuroblastoma cells (SHSY5Y) via cell viability assay, flow cytometry analysis and fluorescence microscopy by means of acridine orange and propidium iodide double staining, to evaluate the anti-apoptotic activity and morphology conservation ability of the compound. Additionally, neurite surface integrity and ultrastructural analysis were carried out by means of scanning and transmission electron microscopy to assess the orientation of surface and internal features of the treated neuronal cells. GMG-ITC pre-treated neuron cells showed significant resistance to H2O2-induced apoptotic cell death, revealing high level of protection by the compound. Increase of intracellular oxidative stress induced by H2O2 was mitigated by GMG-ITC. Thus, pre-treatment with the compound conferred significant protection to cytoskeleton and cytoplasmic inclusion coupled with conservation of surface morphological features and general integrity of neuronal cells. Therefore, the collective findings in the presence study indicated the potentials of GMG-ITC to protect the integrity of neuron cells against induced oxidative-stress related cytotoxic processes, the hallmark of neurodegenerative diseases. PMID:29723199

Induction of cyto-protective autophagy by paramontroseite VO2 nanocrystals

NASA Astrophysics Data System (ADS)

Zhou, Wei; Miao, Yanyan; Zhang, Yunjiao; Liu, Liang; Lin, Jun; Yang, James Y.; Xie, Yi; Wen, Longping

2013-04-01

A variety of inorganic nanomaterials have been shown to induce autophagy, a cellular degradation process critical for the maintenance of cellular homeostasis. The overwhelming majority of autophagic responses elicited by nanomaterials were detrimental to cell fate and contributed to increased cell death. A widely held view is that the inorganic nanoparticles, when encapsulated and trapped by autophagosomes, may compromise the normal autophagic process due to the inability of the cells to degrade these materials and thus they manifest a detrimental effect on the well-being of a cell. Here we show that, contrary to this notion, nano-sized paramontroseite VO2 nanocrystals (P-VO2) induced cyto-protective, rather than death-promoting, autophagy in cultured HeLa cells. P-VO2 also caused up-regulation of heme oxygenase-1 (HO-1), a cellular protein with a demonstrated role in protecting cells against death under stress situations. The autophagy inhibitor 3-methyladenine significantly inhibited HO-1 up-regulation and increased the rate of cell death in cells treated with P-VO2, while the HO-1 inhibitor protoporphyrin IX zinc (II) (ZnPP) enhanced the occurrence of cell death in the P-VO2-treated cells while having no effect on the autophagic response induced by P-VO2. On the other hand, Y2O3 nanocrystals, a control nanomaterial, induced death-promoting autophagy without affecting the level of expression of HO-1, and the pro-death effect of the autophagy induced by Y2O3. Our results represent the first report on a novel nanomaterial-induced cyto-protective autophagy, probably through up-regulation of HO-1, and may point to new possibilities for exploiting nanomaterial-induced autophagy for therapeutic applications.

Isothiocyanate from Moringa oleifera seeds mitigates hydrogen peroxide-induced cytotoxicity and preserved morphological features of human neuronal cells.

PubMed

Jaafaru, Mohammed Sani; Nordin, Norshariza; Shaari, Khozirah; Rosli, Rozita; Abdull Razis, Ahmad Faizal

2018-01-01

Reactive oxygen species are well known for induction of oxidative stress conditions through oxidation of vital biomarkers leading to cellular death via apoptosis and other process, thereby causing devastative effects on the host organs. This effect is believed to be linked with pathological alterations seen in several neurodegenerative disease conditions. Many phytochemical compounds proved to have robust antioxidant activities that deterred cells against cytotoxic stress environment, thus protect apoptotic cell death. In view of that we studied the potential of glucomoringin-isothiocyanate (GMG-ITC) or moringin to mitigate the process that lead to neurodegeneration in various ways. Neuroprotective effect of GMG-ITC was performed on retinoic acid (RA) induced differentiated neuroblastoma cells (SHSY5Y) via cell viability assay, flow cytometry analysis and fluorescence microscopy by means of acridine orange and propidium iodide double staining, to evaluate the anti-apoptotic activity and morphology conservation ability of the compound. Additionally, neurite surface integrity and ultrastructural analysis were carried out by means of scanning and transmission electron microscopy to assess the orientation of surface and internal features of the treated neuronal cells. GMG-ITC pre-treated neuron cells showed significant resistance to H2O2-induced apoptotic cell death, revealing high level of protection by the compound. Increase of intracellular oxidative stress induced by H2O2 was mitigated by GMG-ITC. Thus, pre-treatment with the compound conferred significant protection to cytoskeleton and cytoplasmic inclusion coupled with conservation of surface morphological features and general integrity of neuronal cells. Therefore, the collective findings in the presence study indicated the potentials of GMG-ITC to protect the integrity of neuron cells against induced oxidative-stress related cytotoxic processes, the hallmark of neurodegenerative diseases.

The potential benefits of nicaraven to protect against radiation-induced injury in hematopoietic stem/progenitor cells with relative low dose exposures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ali, Haytham; Department of Medical Physiology and Cell Biology, Qena Faculty of Medicine, South Valley University; Galal, Omima

Highlights: • Nicaraven mitigated the radiation-induced reduction of c-kit{sup +} stem cells. • Nicaraven enhanced the function of hematopoietic stem/progenitor cells. • Complex mechanisms involved in the protection of nicaraven to radiation injury. - Abstract: Nicaraven, a hydroxyl radical-specific scavenger has been demonstrated to attenuate radiation injury in hematopoietic stem cells with 5 Gy γ-ray exposures. We explored the effect and related mechanisms of nicaraven for protecting radiation injury induced by sequential exposures to a relatively lower dose γ-ray. C57BL/6 mice were given nicaraven or placebo within 30 min before exposure to 50 mGy γ-ray daily for 30 days inmore » sequences (cumulative dose of 1.5 Gy). Mice were victimized 24 h after the last radiation exposure, and the number, function and oxidative stress of hematopoietic stem cells were quantitatively estimated. We also compared the gene expression in these purified stem cells from mice received nicaraven and placebo treatment. Nicaraven increased the number of c-kit{sup +} stem/progenitor cells in bone marrow and peripheral blood, with a recovery rate around 60–90% of age-matched non-irradiated healthy mice. The potency of colony forming from hematopoietic stem/progenitor cells as indicator of function was completely protected with nicaraven treatment. Furthermore, nicaraven treatment changed the expression of many genes associated to DNA repair, inflammatory response, and immunomodulation in c-kit{sup +} stem/progenitor cells. Nicaraven effectively protected against damages of hematopoietic stem/progenitor cells induced by sequential exposures to a relatively low dose radiation, via complex mechanisms.« less

Effects of pre-radiation exposure to LLLT of normal and malignant cells.

PubMed

Barasch, Andrei; Raber-Durlacher, Judith; Epstein, Joel B; Carroll, James

2016-06-01

Low-level laser therapy (LLLT) efficacy for the prevention of cancer treatment-induced oral mucositis (OM) has been amply described. However, potential protection of malignant cells remains a legitimate concern for clinicians. We tested LLLT-induced protection from ionizing radiation killing in both malignant and normal cells. We treated six groups each of normal human lymphoblasts (TK6) and human leukemia cells (HL60) with He-Ne LLLT (632.8 nm, 35 mW, CW, 1 cm(2), 35 mW/cm(2) for 3-343 s, 0.1-12 J/cm(2)) prior to exposure to ionizing radiation (IR). Cells were then incubated and counted daily to determine their survival. Optimization of IR dose and incubation time was established prior to testing the effect of LLLT. Growth curves for both cell lines showed significant declines after exposure to 50-200 cGy IR when compared to controls. Pre-radiation exposure to LLLT (4.0 J/cm(2)) followed by 1-h incubation blocked this decline in TK6 but not in HL60 cells. The latter cells were sensitized to the killing effects of IR in a dose-dependent manner. This study shows that pre-IR LLLT treatment results in a differential response of normal vs. malignant cells, suggesting that LLLT does not confer protection and may even sensitize cancer cells to IR killing.

Exosomes derived from human umbilical cord mesenchymal stem cells protect against cisplatin-induced ovarian granulosa cell stress and apoptosis in vitro.

PubMed

Sun, Liping; Li, Dong; Song, Kun; Wei, Jianlu; Yao, Shu; Li, Zhao; Su, Xuantao; Ju, Xiuli; Chao, Lan; Deng, Xiaohui; Kong, Beihua; Li, Li

2017-05-31

Human umbilical cord mesenchymal stem cells (huMSCs) can treat primary ovarian insufficiency (POI) related to ovarian granulosa cell (OGC) apoptosis caused by cisplatin chemotherapy. Exosomes are a class of membranous vesicles with diameters of 30-200 nm that are constitutively released by eukaryotic cells. Exosomes mediate local cell-to-cell communication by transferring microRNAs and proteins. In the present study, we demonstrated the effects of exosomes derived from huMSCs (huMSC-EXOs) on a cisplatin-induced OGC model in vitro and discussed the preliminary mechanisms involved in these effects. We successfully extracted huMSC-EXOs from huMSC culture supernatant and observed the effective uptake of exosomes by cells with fluorescent staining. Using flow cytometry (with annexin-V/PI labelling), we found that huMSC-EXOs increased the number of living cells. Western blotting showed that the expression of Bcl-2 and caspase-3 were upregulated, whilst the expression of Bax, cleaved caspase-3 and cleaved PARP were downregulated to protect OGCs. These results suggest that huMSC-EXOs can be used to prevent and treat chemotherapy-induced OGC apoptosis in vitro. Therefore, this work provides insight and further evidence of stem cell function and indicates that huMSC-EXOs protect OGCs from cisplatin-induced injury in vitro.

Variable effects of the mitoK(ATP) channel modulators diazoxide and 5-HD in ATP-depleted renal epithelial cells.

PubMed

Nilakantan, Vani; Liang, Huanling; Mortensen, Jordan; Taylor, Erin; Johnson, Christopher P

2010-02-01

The role of mitochondrial K(ATP) (mitoK(ATP)) channels in renal ischemia-reperfusion injury is controversial with studies showing both protective and deleterious effects. In this study, we compared the effects of the putative mitoK(ATP) opener, diazoxide, and the mitoK(ATP) blocker, 5-hydroxydecanoate (5-HD) on cytotoxicity and apoptosis in tubular epithelial cells derived from rat (NRK-52E) and pig (LLC-PK1) following in vitro ischemic injury. Following ATP depletion-recovery, there was a significant increase in cytotoxicity in both NRK cells and LLC-PK1 cells although NRK cells were more sensitive to the injury. Diazoxide treatment attenuated cytotoxicity in both cell types and 5-HD treatment-increased cytotoxicity in the sensitive NRK cells in a superoxide-dependant manner. The protective effect of diazoxide was also reversed in the presence of 5-HD in ATP-depleted NRK cells. The ATP depletion-mediated increase in superoxide was enhanced by both diazoxide and 5-HD with the effect being more pronounced in the cells undergoing 5-HD treatment. Further, ATP depletion-induced activation of caspase-3 was decreased by diazoxide in NRK cells. In order to determine the signaling pathways involved in apoptosis, we examined the activation of Erk and JNK in ATP-depleted NRK cells. Diazoxide-activated Erk in ATP-depleted cells, but did not have any effect on JNK activation. In contrast, 5-HD did not impact Erk levels but increased JNK activation even under controlled conditions. Further, the use of a JNK inhibitor with 5-HD reversed the deleterious effects of 5-HD. This study demonstrates that in cells that are sensitive to ATP depletion-recovery, mitoK(ATP) channels protect against ATP depletion-mediated cytotoxicity and apoptosis through Erk- and JNK-dependant mechanisms.

Survival of tissue-resident memory T cells requires exogenous lipid uptake and metabolism

PubMed Central

Pan, Youdong; Tian, Tian; Park, Chang Ook; Lofftus, Serena Y.; Mei, Shenglin; Liu, Xing; Luo, Chi; O’Malley, John T.; Gehad, Ahmed; Teague, Jessica E.; Divito, Sherrie J.; Fuhlbrigge, Robert; Puigserver, Pere; Krueger, James G.; Hotamisligil, Gökhan S.; Clark, Rachael A.; Kupper, Thomas S.

2017-01-01

Tissue-resident memory T (TRM) cells persist indefinitely in epithelial barrier tissues and protect the host against pathogens1–4. However, the biological pathways that enable the long-term survival of TRM cells are obscure4,5. Here we show that mouse CD8+ TRM cells generated by viral infection of the skin differentially express high levels of several molecules that mediate lipid uptake and intracellular transport, including fatty-acid-binding proteins 4 and 5 (FABP4 and FABP5). We further show that T-cell-specific deficiency of Fabp4 and Fabp5 (Fabp4/Fabp5) impairs exogenous free fatty acid (FFA) uptake by CD8+ TRM cells and greatly reduces their long-term survival in vivo, while having no effect on the survival of central memory T (TCM) cells in lymph nodes. In vitro, CD8+ TRM cells, but not CD8+ TCM, demonstrated increased mitochondrial oxidative metabolism in the presence of exogenous FFAs; this increase was not seen in Fabp4/Fabp5 double-knockout CD8+ TRM cells. The persistence of CD8+ TRM cells in the skin was strongly diminished by inhibition of mitochondrial FFA β-oxidation in vivo. Moreover, skin CD8+ TRM cells that lacked Fabp4/Fabp5 were less effective at protecting mice from cutaneous viral infection, and lung Fabp4/Fabp5 double-knockout CD8+ TRM cells generated by skin vaccinia virus (VACV) infection were less effective at protecting mice from a lethal pulmonary challenge with VACV. Consistent with the mouse data, increased FABP4 and FABP5 expression and enhanced extracellular FFA uptake were also demonstrated in human CD8+ TRM cells in normal and psoriatic skin. These results suggest that FABP4 and FABP5 have a critical role in the maintenance, longevity and function of CD8+ TRM cells, and suggest that CD8+ TRM cells use exogenous FFAs and their oxidative metabolism to persist in tissue and to mediate protective immunity. PMID:28219080

Structure-guided design of an invariant natural killer T cell agonist for optimum protection from type 1 diabetes in non-obese diabetic mice

PubMed Central

Blumenfeld, H J; Tohn, R; Haeryfar, S M M; Liu, Y; Savage, P B; Delovitch, T L

2011-01-01

Because invariant natural killer T (iNK T) cells link innate and adaptive immunity, the structure-dependent design of iNK T cell agonists may have therapeutic value as vaccines for many indications, including autoimmune disease. Previously, we showed that treatment of non-obese diabetic (NOD) mice with the iNK T cell activating prototypic glycolipid α-galactosylceramide (α-GalCer) protects them from type 1 diabetes (T1D). However, α-GalCer is a strong agonist that can hyperactivate iNK T cells, elicit several side effects and has shown only limited success in clinical trials. Here, we used a structure-guided design approach to identify an iNK T cell agonist that optimally protects from T1D with minimal side effects. Analyses of the kinetics and function of a panel of synthetic α-GalCer fatty acyl chain derivatives (C8:0-C16:0) were performed in NOD mice. C16:0 elicited the highest protection from insulitis and T1D, which was associated with a higher frequency and survival of iNK T cells and enhanced activity of tolerogenic dendritic cells (DCs) in draining pancreatic lymph nodes (PLN), inability to transactivate NK cells and a more rapid kinetics of induction and recovery of iNK T cells from anergy. We conclude that the length and structure of the acyl chain of α-GalCer regulates the level of protection against T1D in mice, and propose that the extent of this protection depends on the relative capacity of the acyl chain to accommodate an endogenous spacer lipid of appropriate length and structure. Thus, our findings with the α-GalCer C16:0 derivative suggest strongly that it be considered as a lead glycolipid candidate in clinical trials of T1D. PMID:21910729

Protective Effects of Triphala on Dermal Fibroblasts and Human Keratinocytes

PubMed Central

Varma, Sandeep R.; Sivaprakasam, Thiyagarajan O.; Mishra, Abheepsa; Kumar, L. M. Sharath; Prakash, N. S.; Prabhu, Sunil; Ramakrishnan, Shyam

2016-01-01

Human skin is body’s vital organ constantly exposed to abiotic oxidative stress. This can have deleterious effects on skin such as darkening, skin damage, and aging. Plant-derived products having skin-protective effects are well-known traditionally. Triphala, a formulation of three fruit products, is one of the most important rasayana drugs used in Ayurveda. Several skin care products based on Triphala are available that claim its protective effects on facial skin. However, the skin protective effects of Triphala extract (TE) and its mechanistic action on skin cells have not been elucidated in vitro. Gallic acid, ellagic acid, and chebulinic acid were deduced by LC-MS as the major constituents of TE. The identified key compounds were docked with skin-related proteins to predict their binding affinity. The IC50 values for TE on human dermal fibroblasts (HDF) and human keratinocytes (HaCaT) were 204.90 ± 7.6 and 239.13 ± 4.3 μg/mL respectively. The antioxidant capacity of TE was 481.33 ± 1.5 mM Trolox equivalents in HaCaT cells. Triphala extract inhibited hydrogen peroxide (H2O2) induced RBC haemolysis (IC50 64.95 μg/mL), nitric oxide production by 48.62 ± 2.2%, and showed high reducing power activity. TE also rescued HDF from H2O2-induced damage; inhibited H2O2 induced cellular senescence and protected HDF from DNA damage. TE increased collagen-I, involucrin and filaggrin synthesis by 70.72 ± 2.3%, 67.61 ± 2.1% and 51.91 ± 3.5% in HDF or HaCaT cells respectively. TE also exhibited anti-tyrosinase and melanin inhibition properties in a dose-dependent manner. TE increased the mRNA expression of collagen-I, elastin, superoxide dismutase (SOD-2), aquaporin-3 (AQP-3), filaggrin, involucrin, transglutaminase in HDF or HaCaT cells, and decreased the mRNA levels of tyrosinase in B16F10 cells. Thus, Triphala exhibits protective benefits on skin cells in vitro and can be used as a potential ingredient in skin care formulations. PMID:26731545

IGF-1 protects SH-SY5Y cells against MPP+-induced apoptosis via PI3K/PDK-1/Akt pathway.

PubMed

Kim, Chanyang; Park, Seungjoon

2018-03-01

Insulin-like growth factor (IGF)-1 is a well-known anti-apoptotic pro-survival factor and phosphatidylinositol-3-kinase (PI3K)/Akt pathway is linked to cell survival induced by IGF-1. It is also reported that Akt signaling is modulated by 3-phosphoinositide-dependent kinase-1 (PDK1). In the current study, we investigated whether the anti-apoptotic effect of IGF-1 in SH-SY5Y cells exposed to 1-methyl-4-phenylpyridinium (MPP + ) is associated with the activity of PI3K/PDK1/Akt pathway. Treatment of cells with IGF-1 inhibited MPP + -induced apoptotic cell death. IGF-1-induced activation of Akt and the protective effect of IGF-1 on MPP + -induced apoptosis were abolished by chemical inhibition of PDK1 (GSK2334470) or PI3K (LY294002). The phosphorylated levels of Akt and PDK1 were significantly suppressed after MPP + exposure, while IGF-1 treatment completely restored MPP+-induced reductions in phosphorylation. IGF-1 protected cells from MPP + insult by suppressing intracellular reactive oxygen species (ROS) production and malondialdehyde levels and increasing superoxide dismutase activity. Mitochondrial ROS levels were also increased during MPP + exposure, which were attenuated by IGF-1 treatment. In addition, IGF-1-treated cells showed increased activities of succinate dehydrogenase and citrate synthase, stabilization of mitochondrial transmembrane potential, increased ratio of Bcl-2 to Bax, prevention of cytochrome c release and inhibition of caspase-3 activation with PARP cleavage. Furthermore, the protective effects of IGF-1 on oxidative stress and mitochondrial dysfunction were attenuated when cells were preincubated with GSK2334470 or LY294002. Our data suggest that IGF-1 protects SH-SY5Y cells against MPP + -associated oxidative stress by preserving mitochondrial integrity and inhibiting mitochondrial apoptotic cascades via the activation of PI3K/PDK1/Akt pathway. © 2018 The authors.

IGF-1 protects SH-SY5Y cells against MPP+-induced apoptosis via PI3K/PDK-1/Akt pathway

PubMed Central

Kim, Chanyang; Park, Seungjoon

2018-01-01

Insulin-like growth factor (IGF)-1 is a well-known anti-apoptotic pro-survival factor and phosphatidylinositol-3-kinase (PI3K)/Akt pathway is linked to cell survival induced by IGF-1. It is also reported that Akt signaling is modulated by 3-phosphoinositide-dependent kinase-1 (PDK1). In the current study, we investigated whether the anti-apoptotic effect of IGF-1 in SH-SY5Y cells exposed to 1-methyl-4-phenylpyridinium (MPP+) is associated with the activity of PI3K/PDK1/Akt pathway. Treatment of cells with IGF-1 inhibited MPP+-induced apoptotic cell death. IGF-1-induced activation of Akt and the protective effect of IGF-1 on MPP+-induced apoptosis were abolished by chemical inhibition of PDK1 (GSK2334470) or PI3K (LY294002). The phosphorylated levels of Akt and PDK1 were significantly suppressed after MPP+ exposure, while IGF-1 treatment completely restored MPP+-induced reductions in phosphorylation. IGF-1 protected cells from MPP+ insult by suppressing intracellular reactive oxygen species (ROS) production and malondialdehyde levels and increasing superoxide dismutase activity. Mitochondrial ROS levels were also increased during MPP+ exposure, which were attenuated by IGF-1 treatment. In addition, IGF-1-treated cells showed increased activities of succinate dehydrogenase and citrate synthase, stabilization of mitochondrial transmembrane potential, increased ratio of Bcl-2 to Bax, prevention of cytochrome c release and inhibition of caspase-3 activation with PARP cleavage. Furthermore, the protective effects of IGF-1 on oxidative stress and mitochondrial dysfunction were attenuated when cells were preincubated with GSK2334470 or LY294002. Our data suggest that IGF-1 protects SH-SY5Y cells against MPP+-associated oxidative stress by preserving mitochondrial integrity and inhibiting mitochondrial apoptotic cascades via the activation of PI3K/PDK1/Akt pathway. PMID:29459421

Fuzi attenuates diabetic neuropathy in rats and protects schwann cells from apoptosis induced by high glucose.

PubMed

Han, Jing; Tan, Peng; Li, Zhiyong; Wu, Yan; Li, Chun; Wang, Yong; Wang, Beibei; Zhao, Shuang; Liu, Yonggang

2014-01-01

Radix aconite lateralis preparata (Fuzi), a folk medicine, has long been used for the treatment of diabetes and paralysis in China. We examined the effect of Fuzi alone on diabetic rats and Schwann cells in high glucose and the components responsible for its activity. The major constituents of FZE were identified by HPLC-MS/MS data. Male Sprague Dawley rats (n = 36) were randomly divided into control, diabetic, FZE 1.75 g/kg, FZE 3.50 g/kg, FZE 7.00 g/kg, and methylcobalamin groups. After two weeks treatment, nerve conduction velocity and paw withdrawal latency were measured. In vitro, the Schwann cells were grouped according to exposure: normal glucose (NG), normal glucose plus mannitol (NG+M), high glucose (HG), and HG plus different concentrations of FZE (0.1 µg/ml, 1.0 µg/ml, and 10.0 µg/ml). Oxygen free radicals and apoptosis were evaluated through DCFH2DA, DHE and annexin-PE/7-AAD assay, respectively. Apoptosis factors (Bax, Bcl-2, CytoC, caspase-3, and caspase-9) were analyzed using immunofluorescence. Nine alkaloids were identified. The results from animal model showed that FZE was effective in accelerating nerve conduction velocity and shortening paw withdrawal latency in diabetic rats. And in vitro, FZE was also found to protect Schwann cells against high glucose injury. FZE could significantly decrease the apoptotic ratio, superoxide anion and peroxide level. Furthermore, the apoptosis factors, including Bax, Bcl-2, CytoC, caspase-3, and caspase-9 were ameliorated in FZE treated groups. The HPLC-MS(n) method is simple and suitable for the identification of alkaloids in Fuzi. FZE has a protective effect in diabetic neuropathic rats, which is probably achieved by the antiapoptotic effect of FZE on Schwann cells. Apoptosis factor data imply that FZE protected Schwann cells through the mitochondria pathway. Alkaloids are major components contributing to the protective effect.

Snail/beta-catenin signaling protects breast cancer cells from hypoxia attack

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scherbakov, Alexander M., E-mail: alex.scherbakov@gmail.com; Stefanova, Lidia B.; Sorokin, Danila V.

2013-12-10

The tolerance of cancer cells to hypoxia depends on the combination of different factors – from increase of glycolysis (Warburg Effect) to activation of intracellular growth/apoptotic pathways. Less is known about the influence of epithelial–mesenchymal transition (EMT) and EMT-associated pathways on the cell sensitivity to hypoxia. The aim of this study was to explore the role of Snail signaling, one of the key EMT pathways, in the mediating of hypoxia response and regulation of cell sensitivity to hypoxia, using as a model in vitro cultured breast cancer cells. Earlier we have shown that estrogen-independent HBL-100 breast cancer cells differ frommore » estrogen-dependent MCF-7 cells with increased expression of Snail1, and demonstrated Snail1 involvement into formation of hormone-resistant phenotype. Because Snail1 belongs to hypoxia-activated proteins, here we studied the influence of Snail1 signaling on the cell tolerance to hypoxia. We found that Snail1-enriched HBL-100 cells were less sensitive to hypoxia-induced growth suppression if compared with MCF-7 line (31% MCF-7 vs. 71% HBL-100 cell viability after 1% O{sub 2} atmosphere for 3 days). Snail1 knock-down enhanced the hypoxia-induced inhibition of cell proliferation giving the direct evidence of Snail1 involvement into cell protection from hypoxia attack. The protective effect of Snail1 was shown to be mediated, at least in a part, via beta-catenin which positively regulated expression of HIF-1-dependent genes. Finally, we found that cell tolerance to hypoxia was accompanied with the failure in the phosphorylation of AMPK – the key energy sensor, and demonstrated an inverse relationship between AMPK and Snail/beta-catenin signaling. Totally, our data show that Snail1 and beta-catenin, besides association with loss of hormone dependence, protect cancer cells from hypoxia and may serve as an important target in the treatment of breast cancer. Moreover, we suggest that the level of these proteins as well the level of AMPK phosphorylation may be considered as predictors of the tumor sensitivity to anti-angiogenic drugs. - Highlights: • Snail1 protects breast cancer cells from hypoxia. • Protective effect of Snail1 is mediated via β-catenin/HIF-1 pathway. • Snail/β-catenin signaling is negatively controlled by the energy sensor – AMPK. • The failure in AMPK phosphorylation drives cells to the hypoxia-tolerant state.« less

Third-party CD4+ invariant natural killer T cells protect from murine GVHD lethality

PubMed Central

Schneidawind, Dominik; Baker, Jeanette; Pierini, Antonio; Buechele, Corina; Luong, Richard H.; Meyer, Everett H.

2015-01-01

Graft-versus-host disease (GVHD) is driven by extensive activation and proliferation of alloreactive donor T cells causing significant morbidity and mortality following allogeneic hematopoietic cell transplantation (HCT). Invariant natural killer T (iNKT) cells are a potent immunoregulatory T-cell subset in both humans and mice. Here, we explored the role of adoptively transferred third-party CD4+ iNKT cells for protection from lethal GVHD in a murine model of allogeneic HCT across major histocompatibility barriers. We found that low numbers of CD4+ iNKT cells from third-party mice resulted in a significant survival benefit with retained graft-versus-tumor effects. In vivo expansion of alloreactive T cells was diminished while displaying a T helper cell 2-biased phenotype. Notably, CD4+ iNKT cells from third-party mice were as protective as CD4+ iNKT cells from donor mice although third-party CD4+ iNKT cells were rejected early after allogeneic HCT. Adoptive transfer of third-party CD4+ iNKT cells resulted in a robust expansion of donor CD4+CD25+FoxP3+ regulatory T cells (Tregs) that were required for protection from lethal GVHD. However, in vivo depletion of myeloid-derived suppressor cells abrogated both Treg expansion and protection from lethal GVHD. Despite the fact that iNKT cells are a rare cell population, the almost unlimited third-party availability and feasibility of in vitro expansion provide the basis for clinical translation. PMID:25795920

Pre-Treatment with Amifostine Protects against Cyclophosphamide-Induced Disruption of Taste in Mice

PubMed Central

Mukherjee, Nabanita; Carroll, Brittany L.; Spees, Jeffrey L.; Delay, Eugene R.

2013-01-01

Cyclophosphamide (CYP), a commonly prescribed chemotherapy drug, has multiple adverse side effects including alteration of taste. The effects on taste are a cause of concern for patients as changes in taste are often associated with loss of appetite, malnutrition, poor recovery and reduced quality of life. Amifostine is a cytoprotective agent that was previously shown to be effective in preventing chemotherapy-induced mucositis and nephrotoxicity. Here we determined its ability to protect against chemotherapy-induced damage to taste buds using a mouse model of CYP injury. We conducted detection threshold tests to measure changes in sucrose taste sensitivity and found that administration of amifostine 30 mins prior to CYP injection protected against CYP-induced loss in taste sensitivity. Morphological studies showed that pre-treatment with amifostine prevented CYP-induced reduction in the number of fungiform taste papillae and increased the number of taste buds. Immunohistochemical assays for markers of the cell cycle showed that amifostine administration prevented CYP-induced inhibition of cell proliferation and also protected against loss of mature taste cells after CYP exposure. Our results indicate that treatment of cancer patients with amifostine prior to chemotherapy may improve their sensitivity for taste stimuli and protect the taste system from the detrimental effects of chemotherapy. PMID:23626702

Pueraria thunbergiana inhibits cisplatin-induced damage of HEI-OC1 auditory cells through scavenging free radicals.

PubMed

Yu, Hyeon-Hee; Jung, Su-Young; Shin, Mee-Kyung; Park, Raekil; So, Hong-Seob; You, Yong-Ouk

2010-06-01

The radix of Pueraria thunbergiana (P. thunbergiana) is traditionally prescribed to attenuate the clinical manifestation of inner ear dysfunction and various clinical situations including fevers, gastrointestinal disorders, skin problems, migraine headaches, lowering cholesterol, and treating chronic alcoholism in oriental medicine. In the present study, we examined the protective effect of ethanol extract of the radix of P. thunbergiana (RPT) on cisplatin-induced damage of HEI-OC1 auditory hair cells. When the cells were cultured in the medium containing 5-100 microg/mL of RPT, RPT showed protective effect against the cisplatin-induced HEI-OC1 cell damage. We also measured the effects of RPT on lipid peroxidation of cisplatin-treated cells as well as scavenging activities against superoxide radical, hydroxyl radical, hydrogen peroxide, and DPPH radical. RPT reduced cisplatin-induced lipid peroxidation in a dose-dependent manner. Furthermore, RPT showed strong scavenging activity against superoxide radical, hydroxyl radical, hydrogen peroxide, and DPPH radical. These results indicate that RPT protects cisplatin-induced HEI-OC1 cell damage through inhibition of lipid peroxidation and scavenging activities of free radials. (c) 2009 John Wiley & Sons, Ltd.

Roles of Alum and Monophosphoryl Lipid A Adjuvants in Overcoming CD4+ T Cell Deficiency to Induce Isotype-Switched IgG Antibody Responses and Protection by T-Dependent Influenza Vaccine

PubMed Central

Ko, Eun-Ju; Lee, Young-Tae; Kim, Ki-Hye; Lee, Youri; Jung, Yu-Jin; Kim, Min-Chul; Lee, Yu-Na; Kang, Taeuk; Kang, Sang-Moo

2016-01-01

Vaccine adjuvant effects in CD4 deficient condition largely remain unknown. We investigated the roles of combined monophosphoryl lipid A (MPL) and Alum adjuvant (MPL+Alum) in inducing immunity after immunization of CD4-knockout (CD4KO) and wild-type (WT) mice with T-dependent influenza vaccine. MPL+Alum adjuvant mediated IgG isotype-switched antibodies, IgG secreting cell responses, and protection in CD4KO mice, which were comparable to those in WT mice. In contrast, Alum adjuvant effects were dependent on CD4+ T cells. MPL+Alum adjuvant was effective in recruiting monocytes and neutrophils as well as in protecting macrophages from alum-mediated cell loss at the injection site in CD4KO mice. MPL+Alum appeared to attenuate MPL-induced inflammatory responses in WT mice, likely improving the safety. Additional studies in CD4-depleted WT mice and MHCII KO mice suggest that MHCII positive antigen presenting cells contribute to providing alternative B cell help in CD4 deficient condition in the context of MPL+Alum adjuvanted vaccination. PMID:27881702

NELL2 function in the protection of cells against endoplasmic reticulum stress.

PubMed

Kim, Dong Yeol; Kim, Han Rae; Kim, Kwang Kon; Park, Jeong Woo; Lee, Byung Ju

2015-01-01

Continuous intra- and extracellular stresses induce disorder of Ca(2+) homeostasis and accumulation of unfolded protein in the endoplasmic reticulum (ER), which results in ER stress. Severe long-term ER stress triggers apoptosis signaling pathways, resulting in cell death. Neural epidermal growth factor-like like protein 2 (NELL2) has been reported to be important in protection of cells from cell death-inducing environments. In this study, we investigated the cytoprotective effect of NELL2 in the context of ER stress induced by thapsigargin, a strong ER stress inducer, in Cos7 cells. Overexpression of NELL2 prevented ER stress-mediated apoptosis by decreasing expression of ER stress-induced C/EBP homologous protein (CHOP) and increasing ER chaperones. In this context, expression of anti-apoptotic Bcl-xL was increased by NELL2, whereas NELL2 decreased expression of pro-apoptotic proteins, such as cleaved caspases 3 and 7. This anti-apoptotic effect of NELL2 is likely mediated by extracellular signal-regulated kinase (ERK) signaling, because its inhibitor, U0126, inhibited effects of NELL2 on the expression of anti- and pro-apoptotic proteins and on the protection from ER stress-induced cell death.

TLR1/2 activation during heterologous prime-boost vaccination (DNA-MVA) enhances CD8+ T Cell responses providing protection against Leishmania (Viannia).

PubMed

Jayakumar, Asha; Castilho, Tiago M; Park, Esther; Goldsmith-Pestana, Karen; Blackwell, Jenefer M; McMahon-Pratt, Diane

2011-06-01

Leishmania (Viannia) parasites present particular challenges, as human and murine immune responses to infection are distinct from other Leishmania species, indicating a unique interaction with the host. Further, vaccination studies utilizing small animal models indicate that modalities and antigens that prevent infection by other Leishmania species are generally not protective. Using a newly developed mouse model of chronic L. (Viannia) panamensis infection and the heterologous DNA prime - modified vaccinia virus Ankara (MVA) boost vaccination modality, we examined whether the conserved vaccine candidate antigen tryparedoxin peroxidase (TRYP) could provide protection against infection/disease. Heterologous prime - boost (DNA/MVA) vaccination utilizing TRYP antigen can provide protection against disease caused by L. (V.) panamensis. However, protection is dependent on modulating the innate immune response using the TLR1/2 agonist Pam3CSK4 during DNA priming. Prime-boost vaccination using DNA alone fails to protect. Prior to infection protectively vaccinated mice exhibit augmented CD4 and CD8 IFNγ and memory responses as well as decreased IL-10 and IL-13 responses. IL-13 and IL-10 have been shown to be independently critical for disease in this model. CD8 T cells have an essential role in mediating host defense, as CD8 depletion reversed protection in the vaccinated mice; vaccinated mice depleted of CD4 T cells remained protected. Hence, vaccine-induced protection is dependent upon TLR1/2 activation instructing the generation of antigen specific CD8 cells and restricting IL-13 and IL-10 responses. Given the general effectiveness of prime-boost vaccination, the recalcitrance of Leishmania (Viannia) to vaccine approaches effective against other species of Leishmania is again evident. However, prime-boost vaccination modality can with modulation induce protective responses, indicating that the delivery system is critical. Moreover, these results suggest that CD8 T cells should be targeted for the development of a vaccine against infection caused by Leishmania (Viannia) parasites. Further, TLR1/2 modulation may be useful in vaccines where CD8 T cell responses are critical.

Effect of Microcystin-LR on Cultured Rat Endothelial Cells

DTIC Science & Technology

1990-02-26

protection, silymarin , and dithioerythritol 19. ABSTRACT (Continue on reverse if necessary and identify by block number) Primary cultureLs of adult rat...8217 22.g-Ldenine nucleotides, and a small reduction of cell density in endothelial cell monolayers._ Silymarin at 0.2 mM but not(dithioerythritol;at 2.5...monolayers. Silymarin at 0.2 mM but not dithioerythritol at 2.5 mM, partially protected changes in endothelial cells produced by supernatants derived

Protection against RAGE-mediated neuronal cell death by sRAGE-secreting human mesenchymal stem cells in 5xFAD transgenic mouse model.

PubMed

Son, Myeongjoo; Oh, Seyeon; Park, Hyunjin; Ahn, Hyosang; Choi, Junwon; Kim, Hyungho; Lee, Hye Sun; Lee, Sojung; Park, Hye-Jeong; Kim, Seung U; Lee, Bonghee; Byun, Kyunghee

2017-11-01

Alzheimer's disease (AD), which is the most commonly encountered neurodegenerative disease, causes synaptic dysfunction and neuronal loss due to various pathological processes that include tau abnormality and amyloid beta (Aβ) accumulation. Aβ stimulates the secretion and the synthesis of Receptor for Advanced Glycation End products (RAGE) ligand by activating microglial cells, and has been reported to cause neuronal cell death in Aβ 1-42 treated rats and in mice with neurotoxin-induced Parkinson's disease. The soluble form of RAGE (sRAGE) is known to reduce inflammation, and to decrease microglial cell activation and Aβ deposition, and thus, it protects from neuronal cell death in AD. However, sRAGE protein has too a short half-life for therapeutic purposes. We developed sRAGE-secreting umbilical cord derived mesenchymal stem cells (sRAGE-MSCs) to enhance the inhibitory effects of sRAGE on Aβ deposition and to reduce the secretion and synthesis of RAGE ligands in 5xFAD mice. In addition, these cells improved the viability of injected MSCs, and enhanced the protective effects of sRAGE by inhibiting the binding of RAGE and RAGE ligands in 5xFAD mice. These findings suggest sRAGE protein from sRAGE-MSCs has better protection against neuronal cell death than sRAGE protein or single MSC treatment by inhibiting the RAGE cell death cascade and RAGE-induce inflammation. Copyright © 2017 Elsevier Inc. All rights reserved.

Radical-scavenging abilities and antioxidant properties of theaflavins and their gallate esters in H2O2-mediated oxidative damage system in the HPF-1 cells.

PubMed

Yang, Ziyin; Jie, Guoliang; Dong, Fang; Xu, Yi; Watanabe, Naoharu; Tu, Youying

2008-08-01

The antioxidant properties of theaflavins and their gallate esters, namely theaflavin (TF1), theaflavin-3(3')-gallate (TF2) and theaflavin-3,3'-digallate (TF3) were investigated by comparing with epigallocatechin gallate (EGCG). The order of hydroxyl radicals-scavenging ability was TF3>TF2>TF1>EGCG. The order of 2,2-diphenyl-1-picrylhydrazyl scavenging ability was TF3>TF2>EGCG>TF1. TF1, TF2, and TF3 showed more effective effects than EGCG in protection against H2O2-mediated damage in HPF-1 cells. TF2 was the most potent accelerant of HPF-1 cell proliferation. TF1, TF2 and TF3 suppressed the accumulation of intracellular reactive species in H2O2-mediated damage HPF-1 cells. Pre-treated for 2h and eliminated from the cells, TF1 and TF3 still showed protective effects against H2O2-mediated damage in HPF-1 cells. This suggests that the protective effects of TF1 and TF3 on oxidative damage HPF-1 cells may be responsible for other mechanisms, rather than only scavenging the already formed reactive species. It remains to be determined whether TF1 and TF3 improved the normal HPF-1 cell resistive abilities toward radical-damage in pre-treatment. Further studies of the effects of theaflavins on some enzymes or signal transduction in the normal HPF-1 cells are underway.

Mechanisms of immunity in post-exposure vaccination against Ebola virus infection.

PubMed

Bradfute, Steven B; Anthony, Scott M; Stuthman, Kelly S; Ayithan, Natarajan; Tailor, Prafullakumar; Shaia, Carl I; Bray, Mike; Ozato, Keiko; Bavari, Sina

2015-01-01

Ebolaviruses can cause severe hemorrhagic fever that is characterized by rapid viral replication, coagulopathy, inflammation, and high lethality rates. Although there is no clinically proven vaccine or treatment for Ebola virus infection, a virus-like particle (VLP) vaccine is effective in mice, guinea pigs, and non-human primates when given pre-infection. In this work, we report that VLPs protect Ebola virus-infected mice when given 24 hours post-infection. Analysis of cytokine expression in serum revealed a decrease in pro-inflammatory cytokine and chemokine levels in mice given VLPs post-exposure compared to infected, untreated mice. Using knockout mice, we show that VLP-mediated post-exposure protection requires perforin, B cells, macrophages, conventional dendritic cells (cDCs), and either CD4+ or CD8+ T cells. Protection was Ebola virus-specific, as marburgvirus VLPs did not protect Ebola virus-infected mice. Increased antibody production in VLP-treated mice correlated with protection, and macrophages were required for this increased production. However, NK cells, IFN-gamma, and TNF-alpha were not required for post-exposure-mediated protection. These data suggest that a non-replicating Ebola virus vaccine can provide post-exposure protection and that the mechanisms of immune protection in this setting require both increased antibody production and generation of cytotoxic T cells.

Melatonin pre-treatment mitigates SHSY-5Y cells against oxaliplatin induced mitochondrial stress and apoptotic cell death

PubMed Central

Choudhury, Arnab; Kar, Sudeshna; Tabassum, Heena

2017-01-01

Oxaliplatin (Oxa) treatment to SH-SY5Y human neuroblastoma cells has been shown by previous studies to induce oxidative stress, which in turn modulates intracellular signaling cascades resulting in cell death. While this phenomenon of Oxa-induced neurotoxicity is known, the underlying mechanisms involved in this cell death cascade must be clarified. Moreover, there is still little known regarding the roles of neuronal mitochondria and cytosolic compartments in mediating Oxa-induced neurotoxicity. With a better grasp of the mechanisms driving neurotoxicity in Oxa-treated SH-SY5Y cells, we can then identify certain pathways to target in protecting against neurotoxic cell damage. Therefore, the purpose of this study was to determine whether one such agent, melatonin (Mel), could confer protection against Oxa-induced neurotoxicity in SH-SY5Y cells. Results from the present study found Oxa to significantly reduce SH-SY5Y cell viability in a dose-dependent manner. Alternatively, we found Mel pre-treatment to SH-SY5Y cells to attenuate Oxa-induced toxicity, resulting in a markedly increased cell viability. Mel exerted its protective effects by regulating reactive oxygen species (ROS) production and reducing superoxide radicals inside Oxa-exposed. In addition, we observed pre-treatment with Mel to rescue Oxa-treated cells by protecting mitochondria. As Oxa-treatment alone decreases mitochondrial membrane potential (Δψm), resulting in an altered Bcl-2/Bax ratio and release of sequestered cytochrome c, so Mel was shown to inhibit these pathways. Mel was also found to inhibit proteolytic activation of caspase 3, inactivation of Poly (ADP Ribose) polymerase, and DNA damage, thereby allowing SH-SY5Y cells to resist apoptotic cell death. Collectively, our results suggest a role for melatonin in reducing Oxa induced neurotoxicity. Further studies exploring melatonin’s protective effects may prove successful in eliciting pathways to further alter the neurotoxic pathways of platinum compounds in cancer treatment. PMID:28732061

Neuroprotective Effects of Nonfeminizing Estrogens in Retinal Photoreceptor Neurons

PubMed Central

Nixon, Everett; Simpkins, James W.

2012-01-01

Purpose. Retinal diseases such as macular degeneration and glaucoma are disorders that target specific retinal neurons that can ultimately lead to vision loss. Under these conditions and pathologies, retinal neurons can die via apoptosis that may be due to increased oxidative stress. The neuroprotective effects of 17β-estradiol (E2) and three synthetic nonfeminizing estrogen analogs (ZYC-26, ZYC-23, and ZYC-3) were investigated to examine their abilities to protect retinal neurons against glutamate toxicity. Methods. Using an in vitro model of glutamate-induced cell death in 661W cells, a mouse cone photoreceptor cell line, shown to express both estrogen receptors (ERs) via immunoblotting, was pretreated with E2 and its analogs and cell viability were assessed. Results. It was observed that E2 and estrogen analogs, ZYC-26 and ZYC-3, were protective against a 5 mM glutamate insult in 661W cells. The neuroprotective abilities of ZYC-26 and ZYC-3 were autonomous of estrogen receptor-α (ERα) and ERβ demonstrated by their ability to protect in the presence of ICI 182780, a pan-ER antagonist with a high affinity for the estrogen receptor. Treatment with PPT and DPN, ERα- and ERβ-specific agonists, respectively, did not protect the 661W cells from the glutamate insult. Studying the membrane ER (mER) or GPR30 did show that activation of the receptor by G1 protected the retinal neuron from insult, whereas G15, an antagonist of the mER was not able to antagonize the protection previously seen. Conclusions. These data demonstrate that nonfeminizing estrogens may emerge as useful compounds for neuroprotection of retinal cells. PMID:22700711

Protective Effect of Chitin Urocanate Nanofibers against Ultraviolet Radiation

PubMed Central

Ito, Ikuko; Yoneda, Toshikazu; Omura, Yoshihiko; Osaki, Tomohiro; Ifuku, Shinsuke; Saimoto, Hiroyuki; Azuma, Kazuo; Imagawa, Tomohiro; Tsuka, Takeshi; Murahata, Yusuke; Ito, Norihiko; Okamoto, Yoshiharu; Minami, Saburo

2015-01-01

Urocanic acid is a major ultraviolet (UV)-absorbing chromophore. Chitins are highly crystalline structures that are found predominantly in crustacean shells. Alpha-chitin consists of microfibers that contain nanofibrils embedded in a protein matrix. Acid hydrolysis is a common method used to prepare chitin nanofibrils (NFs). We typically obtain NFs by hydrolyzing chitin with acetic acid. However, in the present study, we used urocanic acid to prepare urocanic acid chitin NFs (UNFs) and examined its protective effect against UVB radiation. Hos: HR-1 mice coated with UNFs were UVB irradiated (302 nm, 150 mJ/cm2), and these mice showed markedly lower UVB radiation-induced cutaneous erythema than the control. Additionally, sunburn cells were rarely detected in the epidermis of UNFs-coated mice after UVB irradiation. Although the difference was not as significant as UNFs, the number of sunburn cells in mice treated with acetic acid chitin nanofibrils (ANFs) tended to be lower than in control mice. These results demonstrate that ANFs have a protective effect against UVB and suggest that the anti-inflammatory and antioxidant effects of NFs influence the protective effect of ANFs against UVB radiation. The combination of NFs with other substances that possess UV-protective effects, such as urocanic acid, may provide an enhanced protective effect against UVB radiation. PMID:26703629

HIV-specific Th2 and Th17 responses predict HIV vaccine protection efficacy

PubMed Central

Sauce, Delphine; Gorochov, Guy; Larsen, Martin

2016-01-01

Understanding the factors that delineate the efficacy of T-cell responses towards pathogens is crucial for our ability to develop potent therapies and vaccines against infectious diseases, such as HIV. Here we show that a recently developed analytical tool, the polyfunctionality index (PI), not only enables prediction of protection after vaccination against HIV, but also allows identification of the immunological pathways involved. Our data suggest that induction of a synergistic network of CD4+ T-cell subsets is implicated in HIV-protection. Accordingly, we provide evidence that vaccine-induced protection is associated with CD40L expressing Th2 cells and IL-2 secreting Th17 cells. In conclusion, we describe a novel approach that is widely applicable and readily interpretable in a biological and clinical context. This approach could greatly impact our fundamental understanding of T-cell immunity as well as the search for effective vaccines. PMID:27324186

Promising Diabetes Therapy Based on the Molecular Mechanism for Glucose Toxicity: Usefulness of SGLT2 Inhibitors as well as Incretin-Related Drugs.

PubMed

Kaneto, Hideaki; Obata, Atsushi; Shimoda, Masashi; Kimura, Tomohiko; Hirukawa, Hidenori; Okauchi, Seizo; Matsuoka, Taka-Aki; Kaku, Kohei

2016-01-01

Pancreatic β-cell dysfunction and insulin resistance are the main characteristics of type 2 diabetes. Chronic exposure of β-cells to hyperglycemia leads to the deterioration of β-cell function. Such phenomena are well known as pancreatic β-cell glucose toxicity. MafA, a strong transactivator of insulin gene, is particularly important for the maintenance of mature β-cell function, but its expression level is significantly reduced under diabetic conditions which is likely associated with β-cell failure. Reduction of incretin receptor expression level in β-cells in diabetes is also likely associated with β-cell failure. On the other hand, incretin-related drugs and sodium-glucose co-transporter 2 (SGLT2) inhibitors are promising diabetes therapy based on the mechanism for pancreatic β-cell glucose toxicity. Indeed, it was shown that incretin-related drugs exerted protective effects on β-cells through the augmentation of IRS-2 expression especially in the presence of pioglitazone. It was also shown that incretin-related drug and/or pioglitazone exerted more protective effects on β-cells at the early stage of diabetes compared to the advanced stage. SGLT2 inhibitors, new hypoglycemic agents, also exert beneficial effects for the protection of pancreatic β-cells as well as for the reduction of insulin resistance in various insulin target tissues. Taken together, it is important to select appropriate therapy based on the molecular mechanism for glucose toxicity.

Protective effects of Korean red ginseng against radiation-induced apoptosis in human HaCaT keratinocytes

PubMed Central

Chang, Jae Won; Park, Keun Hyung; HWANG, Hye Sook; Shin, Yoo Seob; Oh, Young-Taek; Kim, Chul-Ho

2014-01-01

Radiation-induced oral mucositis is a dose-limiting toxic side effect for patients with head and neck cancer. Numerous attempts at improving radiation-induced oral mucositis have not produced a qualified treatment. Ginseng polysaccharide has multiple immunoprotective effects. Our aim was to investigate the effectiveness of Korean red ginseng (KRG) on radiation-induced damage in the human keratinocyte cell line HaCaT and in an in vivo zebrafish model. Radiation inhibited HaCaT cell proliferation and migration in a cell viability assay and wound healing assay, respectively. KRG protected against these effects. KRG attenuated the radiation-induced embryotoxicity in the zebrafish model. Irradiation of HaCaT cells caused apoptosis and changes in mitochondrial membrane potential (MMP). KRG inhibited the radiation-induced apoptosis and intracellular generation of reactive oxygen species (ROS), and stabilized the radiation-induced loss of MMP. Western blots revealed KRG-mediated reduced expression of ataxia telangiectasia mutated protein (ATM), p53, c-Jun N-terminal kinase (JNK), p38 and cleaved caspase-3, compared with their significant increase after radiation treatment. The collective results suggest that KRG protects HaCaT cells by blocking ROS generation, inhibiting changes in MMP, and inhibiting the caspase, ATM, p38 and JNK pathways. PMID:24078877

Chitooligosaccharides protect human embryonic hepatocytes against oxidative stress induced by hydrogen peroxide.

PubMed

Xu, Qingsong; Ma, Pan; Yu, Weiting; Tan, Chengyu; Liu, Hongtao; Xiong, Chuannan; Qiao, Ying; Du, Yuguang

2010-06-01

Chitooligosaccharides (COS) has many biological activities, such as antitumor activity and hepatoprotective effect. Herein, we investigated the protective effect of COS against hydrogen peroxide (H2O2)-induced oxidative stress on human embryonic hepatocytes (L02 cells) and its scavenging activity against the 1,1-diphenyl-2-picrylhydrazyl radical in vitro. The results showed that the lost cell viability induced by H2O2 was markedly restored after 24 h pre-incubation with COS (0.1-0.4 mg/ml). This rescue effect could be related to the antioxidant property of COS, in which we showed that the radical scavenging activity of COS reached 80% at concentration of 2 mg/ml. In addition, COS could prevent cell apoptosis induced by H2O2, as shown by the inhibition of the cleavage of poly (adenosine diphosphate-ribose) polymerase and increased expression of the anti-apoptotic protein Bcl-xL. Furthermore, we have utilized confocal laser microscopy to observe cellular uptake of COS, an important step for COS to exert its effects on target cells. Taken together, our findings suggested that COS could effectively protect L02 cells against oxidative stress, which might be useful in clinical setting during the treatment of oxidative stress-related liver damages.

Protective effects of Korean red ginseng against radiation-induced apoptosis in human HaCaT keratinocytes.

PubMed

Chang, Jae Won; Park, Keun Hyung; Hwang, Hye Sook; Shin, Yoo Seob; Oh, Young-Taek; Kim, Chul-Ho

2014-03-01

Radiation-induced oral mucositis is a dose-limiting toxic side effect for patients with head and neck cancer. Numerous attempts at improving radiation-induced oral mucositis have not produced a qualified treatment. Ginseng polysaccharide has multiple immunoprotective effects. Our aim was to investigate the effectiveness of Korean red ginseng (KRG) on radiation-induced damage in the human keratinocyte cell line HaCaT and in an in vivo zebrafish model. Radiation inhibited HaCaT cell proliferation and migration in a cell viability assay and wound healing assay, respectively. KRG protected against these effects. KRG attenuated the radiation-induced embryotoxicity in the zebrafish model. Irradiation of HaCaT cells caused apoptosis and changes in mitochondrial membrane potential (MMP). KRG inhibited the radiation-induced apoptosis and intracellular generation of reactive oxygen species (ROS), and stabilized the radiation-induced loss of MMP. Western blots revealed KRG-mediated reduced expression of ataxia telangiectasia mutated protein (ATM), p53, c-Jun N-terminal kinase (JNK), p38 and cleaved caspase-3, compared with their significant increase after radiation treatment. The collective results suggest that KRG protects HaCaT cells by blocking ROS generation, inhibiting changes in MMP, and inhibiting the caspase, ATM, p38 and JNK pathways.

IFN-Gamma-Dependent and Independent Mechanisms of CD4⁺ Memory T Cell-Mediated Protection from Listeria Infection.

PubMed

Meek, Stephanie M; Williams, Matthew A

2018-02-13

While CD8⁺ memory T cells can promote long-lived protection from secondary exposure to intracellular pathogens, less is known regarding the direct protective mechanisms of CD4⁺ T cells. We utilized a prime/boost model in which mice are initially exposed to an acutely infecting strain of lymphocytic choriomeningitis virus (LCMV), followed by a heterologous rechallenge with Listeria monocytogenes recombinantly expressing the MHC Class II-restricted LCMV epitope, GP 61-80 (Lm-gp61). We found that heterologous Lm-gp61 rechallenge resulted in robust activation of CD4⁺ memory T cells and that they were required for rapid bacterial clearance. We further assessed the relative roles of TNF and IFNγ in the direct anti-bacterial function of CD4⁺ memory T cells. We found that disruption of TNF resulted in a complete loss of protection mediated by CD4⁺ memory T cells, whereas disruption of IFNγ signaling to macrophages results in only a partial loss of protection. The protective effect mediated by CD4⁺ T cells corresponded to the rapid accumulation of pro-inflammatory macrophages in the spleen and an altered inflammatory environment in vivo. Overall, we conclude that protection mediated by CD4⁺ memory T cells from heterologous Listeria challenge is most directly dependent on TNF, whereas IFNγ only plays a minor role.

[UV-induced DNA damage and protective effects of antioxidants on DNA damage in human lens epithelial cells studied with comet assay].

PubMed

Wu, Zhi-hong; Wang, Mian-rong; Yan, Qi-chang; Pu, Wei; Zhang, Jin-song

2006-11-01

To investigate the mechanism of UV-induced DNA damage and repair and the protective effects of antioxidants on DNA damage in human lens epithelial cells. Human lens epithelial cells were irradiated at UV-doses 0.0 (control group), 2.5, 5.0, 7.5, 10.0 mJ/cm(2) (treated group 1 - 4). The amounts of DNA single strand breaks (SSB) were measured with the alkaline comet assay (CA). The spontaneous repair of DNA SSB after exposure to UV at 10.0 mJ/cm(2) was also determined in human lens epithelial cells. Human lens epithelial cells were treated with different concentration of VitaminC (VitC), taurine, superoxide dismutase (SOD) and epigallocatechin gallate (EGCG) before and after ultraviolet radiation, the effects of antioxidants on DNA damage was examined with alkaline comet assay. The amount of DNA SSB in control group and treated groups 1 - 4 showed increased tendency, was dose-dependent to the dose of UV irradiation, the differences of DNA SSB in 5 group were significantly (P < 0.01). UV-induced DNA SSB at 10.0 mJ/cm(2) in human lens epithelial cells, the half repair time was 60 minutes. Human lens epithelial cells were treated with different concentrations of taurine, SOD and EGCG before ultraviolet radiation. The differences of DNA damage in control and various antioxidant treated groups was statistically significant (F = 6.591, 13.542, 4.626 in cells treated with taurine, SOD and EGCG, respectively, P < 0.01), the difference of VitC effect on DNA in control and treated group were not significantly (F = 1.451, P > 0.05). Human lens epithelial cells were treated with different concentration of VitC, taurine, SOD and EGCG after ultraviolet radiation. The differences of DNA damage between the control and treated group were statistically significant (F = 6.571, 4.810, 6.824, 9.182 in cells treated with VitC, taurine, SOD and EGCG, respectively, P < 0.01). The differences of protective effects on DNA damage in these four different kinds of antioxidants added before UV irradiation were statistically significant (P < 0.01). The differences of protective effects on DNA damage in these four different kinds of antioxidant added after UV irradiation were not significantly (P > 0.05). UV irradiation has a dose-dependent effect on the DNA SSB of lens epithelial cells. Exogenesis VitC, taurine, SOD, EGCG possess protective effective to UV-induced DNA damage. SOD is one of the most powerful antioxidants if added before the UV irradiation and followed by EGCG, taurine and VitC orderly. Four kinds of antioxidants show no apparently differences added after UV-irradiation. SOD and EGCG both are powerful antioxidants.

Vitamin C Protected Human Retinal Pigmented Epithelium from Oxidant Injury Depending on Regulating SIRT1

PubMed Central

Wei, Wei; Li, Langen; Zhang, Yufeng; Geriletu; Yang, Jia; Zhang, Yanmei; Xing, Yiqiao

2014-01-01

The purpose was to investigate the protective effects of Vitamin C (Vit C) and the regulatory mechanism between Vit C and sirtuin 1 (SIRT1) in PREs during oxidative stress as Vit C and SIRT1 exerted famous effects as antioxidants. We found that moderate Vit C (100 µM) prevented ARPE-19 cells from damages induced by H2O2, including increasing viability, reducing apoptosis, and attenuating intracellular ROS levels. But lower and higher concentration of Vit C had no effects. Further results indicated that Vit C caused the dysregulation of some stress responses factors (SIRT1, p53 and FOXO3) in ARPE-19 cells response to H2O2. Moreover we found that SIRT1 activator resveratrol (SRV) stimulated significantly the protective effects of moderate Vit C, provided the property of antioxidative stress for the lower and higher concentration of Vit C in ARPE-19 cells as well. Consistently, nicotinamide (NA) relieved the protective functions of moderate Vit C. Interestingly, data also revealed the dysregulation of p53 and FOXO3 was dependent on the regulation of SIRT1 rather than Vit C. Summarily, the protective effect of Vit C against oxidative stress was involved in regulation of SIRT1. It suggested that combined application of Vit C and RSV might be a promising therapeutic method for AMD. PMID:25147862

Artemisinin Protects Retinal Neuronal Cells against Oxidative Stress and Restores Rat Retinal Physiological Function from Light Exposed Damage.

PubMed

Yan, Fengxia; Wang, Haitao; Gao, Yang; Xu, Jiangping; Zheng, Wenhua

2017-08-16

Oxidative stress plays a key role in the pathogenesis of age-related macular degeneration (AMD), a leading cause of severe visual loss and blindness in the aging population which lacks any effective treatments currently. In this study, artemisinin, a well-known antimalarial drug was found to suppress hydrogen peroxide (H 2 O 2 )-induced cell death in retinal neuronal RGC-5 cells. Artemisinin, in the therapeutically relevant dosage, concentration-dependently attenuated the accumulation of intracellular reactive oxygen species (ROS), increased mitochondrial membrane potential and decreased cell apoptosis in RGC-5 cells induced by H 2 O 2 . Western blot analysis showed that artemisinin upregulated the phosphorylation of p38 and extracellular signal-regulated kinases1/2 (ERK1/2) and reversed the inhibitory effect of H 2 O 2 on the phosphorylation of these two kinases. Moreover, protective effect of artemisinin was blocked by the p38 kinase inhibitor PD169316 or ERK1/2 kinase pathway inhibitor PD98059, respectively. In contrast, c-Jun N-terminal kinase inhibitor and rapamycin had no effect in the protective effect of artemisinin. Taken together, these results demonstrated that artemisinin promoted the survival of RGC-5 cells from H 2 O 2 toxicity via the activation of the p38 and ERK1/2 pathways. Interestingly, intravitreous injection of artimisinin, concentration-dependently reversed light exposed-damage (a dry AMD animal model) of rat retinal physiological function detected by flash electroretinogram. These results indicate that artemisinin can protect retinal neuronal functions from H 2 O 2 -induced damage in vitro and in vivo and suggest the potential application of artemisinin as a new drug in the treatment of retinal disorders like AMD.

Lithium as a prooxidant? A possible protective role of selenium - in vitro study.

PubMed

Musik, Irena; Kiełczykowska, Małgorzata; Rajtar, Barbara; Świątek, Łukasz; Polz-Dacewicz, Małgorzata; Kocot, Joanna

2017-09-21

Lithium is used in medicine but its application may cause diverse side effects. Selenium has been found to show protective properties against negative influence of different harmful factors. This study was aimed at evaluating the influence of non-toxic dose of lithium on antioxidant parameters in FaDu (ATCC HTB-43) and Vero (ECACC No. 84113001) cell lines as well as the possible protective effect of non-toxic concentration of sodium selenite. The cells were subjected to 0.17 mmol/L of Li₂CO₃ and/or 2.9 µmol/L of Na₂SeO₃ · 5H₂O for Vero as well as 0.47 mmol/L of Li₂CO₃ and/or 3.0 µmol/L of Na₂SeO₃ · 5H₂O for FaDu cells. The incubation was continued for the subsequent 72 h. In the cells total antioxidant status (TAS) values, activities of antioxidant enzymes - superoxide dismutase (SOD) and glutathione peroxidase (GPx) as well as the reduced glutathione concentration (GSH) were determined. In Vero cells lithium decreased all studied parameters, particularly GPx. Selenium co-treatment showed a distinct protective effect. In FaDu cells the similar effect was observed only in case of GSH. The results point to differences in action of lithium and selenium in physiological and pathological state. As long-term lithium therapy is applied in psychiatric patients the results regarding Vero line let suggest that selenium might be considered as an adjuvant alleviating side effects of Li-treatment.

Resveratrol protects against hyperglycemia-induced oxidative damage to mitochondria by activating SIRT1 in rat mesangial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Ying; Nie, Ling; Yin, Yang-Guang

2012-03-15

Oxidative stress and mitochondrial dysfunction are involved in the pathogenesis of diabetic nephropathy (DN). Resveratrol has potent protective effects on diabetes and diabetic complications including diabetic nephropathy. We aimed to investigate the protective effects of resveratrol on mitochondria and the underlying mechanisms by using an in vitro model of hyperglycemia. We exposed primary cultured rat mesangial cells to high glucose (30 mM) for 48 h. We found that pretreatment with resveratrol (10 μM) 6 h prior to high glucose treatment significantly reduced hyperglycemia-induced increase in reactive oxygen species (ROS) production and mitochondrial superoxide generation, as well as stimulated MnSOD activity.more » In addition, resveratrol pretreatment significantly reversed the decrease of mitochondrial complex III activity in glucose-treated mesangial cells, which is considered to be the major source of mitochondrial oxidative stress in glucose-treated cells. Furthermore, resveratrol pretreatment efficiently restored the hyperpolarization of ∆Ψm, increased ATP production and preserved the mtDNA content. All of these protective effects of resveratrol were successfully blocked by siRNA targeting SIRT1 and EX-527, a specific inhibitor of SIRT1 activity. Our results indicated that resveratrol efficiently reduced oxidative stress and maintained mitochondrial function related with activating SIRT1 in glucose-treated mesangial cells. It suggested that resveratrol is pharmacologically promising for treating diabetic nephropathy. -- Highlights: ► We treat mesangial cells with glucose as an in vitro model of diabetic nephropathy. ► We find that the nephroprotective effects of resveratrol relate with mitochondria. ► The beneficial effect of resveratrol was prevented by siRNA SIRT1 or its inhibitor.« less

Sensitization of thermotolerant SCK cells to hyperthermia and freezing with reduction of intracellular pH: implications for cryosurgery.

PubMed

Burgher, Abram H; Swanlund, David J; Griffin, Robert J; Song, Chang W; Bischof, John C; Roberts, Kenneth P

2003-03-01

During cryosurgery, cells frozen slowly at the outer part of the ice ball undergo severe dehydration and are subject to solute effects injury, which may be caused in part by protein denaturation. This study was undertaken to determine whether heat shock proteins (HSPs), the molecular chaperones that stabilize proteins against denaturation, have a protective effect on cells during slow freezing. In addition, we aimed to determine whether acidic conditions, similar to those found in many solid tumors, would effect this protection. SCK cells were frozen at 5 degrees C/min to -10 degrees C or -20 degrees C before or after induction of thermotolerance, and at neutral or low pH conditions. Lethal damage was determined by clonogenics. Clonogenic survival was decreased by 50% in thermotolerant cells frozen to -10 degrees C after culture in acidic conditions (pH 6.6) compared with non-thermotolerant cells cultured at neutral pH. Induction of thermotolerance alone or low pH alone did not significantly sensitize SCK cells to freezing. All treatment groups were equally susceptible to killing when frozen to -20 degrees C. Our results show that induction of thermal tolerance does not protect SCK cells against subsequent freezing injury and that a low pH environment actually sensitizes these cells to freeze injury. Copyright 2003 Wiley-Liss, Inc.

Generation of protective T cell-independent antiviral antibody responses in SCID mice reconstituted with follicular or marginal zone B cells.

PubMed

Guay, Heath M; Mishra, Rabinarayan; Garcea, Robert L; Welsh, Raymond M; Szomolanyi-Tsuda, Eva

2009-07-01

B cells generated in the bone marrow of adult mice enter the periphery as transitional B cells and subsequently differentiate into one of two phenotypically and functionally distinct subsets, marginal zone (MZ) or follicular (Fo) B cells. Recent reports indicate, however, that in response to environmental cues, such as lymphopenia, mature Fo B cells can change to display phenotypic markers characteristic of MZ B cells. Previously, we found that splenic B cells transferred to SCID mice responded to polyoma virus (PyV) infection with T cell-independent (TI) IgM and IgG secretion, reducing the viral load and protecting mice from the lethal effect of the infection. The contribution of MZ and Fo B cell subsets to this antiviral TI-2 response, however, has not been addressed. In this study, we show that both sort-purified MZ and Fo B cells generate protective TI Ab responses to PyV infection when transferred into SCID mice. Moreover, the transferred Fo B cells in the spleens of the PyV-infected SCID mice change phenotype, with many of them displaying MZ B cell characteristics. These findings demonstrate the plasticity of the B cell subsets in virus-infected hosts and show for the first time that B cells derived exclusively from Fo B cells can effectively function in antiviral TI-2 responses.

Lung dendritic cells imprint T cell lung homing and promote lung immunity through the chemokine receptor CCR4

PubMed Central

Strassner, James P.

2013-01-01

T cell trafficking into the lung is critical for lung immunity, but the mechanisms that mediate T cell lung homing are not well understood. Here, we show that lung dendritic cells (DCs) imprint T cell lung homing, as lung DC–activated T cells traffic more efficiently into the lung in response to inhaled antigen and at homeostasis compared with T cells activated by DCs from other tissues. Consequently, lung DC–imprinted T cells protect against influenza more effectively than do gut and skin DC–imprinted T cells. Lung DCs imprint the expression of CCR4 on T cells, and CCR4 contributes to T cell lung imprinting. Lung DC–activated, CCR4-deficient T cells fail to traffic into the lung as efficiently and to protect against influenza as effectively as lung DC–activated, CCR4-sufficient T cells. Thus, lung DCs imprint T cell lung homing and promote lung immunity in part through CCR4. PMID:23960189

Hydroxysafflor yellow A cardioprotection in ischemia-reperfusion (I/R) injury mainly via Akt/hexokinase II independent of ERK/GSK-3β pathway.

PubMed

Min, Jia; Wei, Cui

2017-03-01

Hydroxysafflor yellow A (HSYA) is the main active component of Carthamus tinctorius L which has been used for hundreds of years in Chinese folk medicine in the treatment cardiovascular disease. This study was designed to investigate whether HSYA exerts cardioprotection in ischemia-reperfusion (I/R) injury heart and the mechanisms involved. The protective effect and mechanisms in myocardial ischemia reperfusion injury of HSYA was evaluated by hypoxia-recover (H/R) injury cell model which induced by hypoxia and recovered with oxygen in H9c2 cells. PI3K/Akt and ERK as the reperfusion injury salvage kinase (RISK) pathway and Hexokinase II (HKII) were both examined. In H/R cell model, HSYA significantly reduced dehydrogenase (LDH), Caspase 3 level, alleviated oxidative stress injury and apoptosis, meanwhile restored mitochondrial energy metabolism. Pretreatment with PI3K inhibitor (LY294002) or hexokinase II inhibitor (3-BrPA), the protective effect of HSYA was significantly attenuated. On the contrary, pretreatment with ERK inhibitor (PD98059), the protective effect of HSYA on myocardial cells was decreased slightly, not as significant as PI3K inhibitor or hexokinase II inhibitor. ERK play a protective role in myocardial protection by phosphorylation of GSK3-β, but the effect of HSYA on phosphorylation of GSK3-β is weakly, however the effect of HSYA on Akt and hexokinase II were significantly up-regulated. Meanwhile, the phosphorylation of GSK3-β by HSYA was significantly reduced after gave the ERK inhibitor and had no significant difference between the model group. The cardioprotection effect of HSYA appears to be mainly mediated via the PI3K/Akt/hexokinase II. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Cytoprotective Effect of Epigallocatechin Gallate (EGCG)-5'-O-α-Glucopyranoside, a Novel EGCG Derivative.

PubMed

Han, Sang Yun; Kim, Eunji; Hwang, Kyeonghwan; Ratan, Zubair Ahmed; Hwang, Hyunsik; Kim, Eun-Mi; Kim, Doman; Park, Junseong; Cho, Jae Youl

2018-05-15

Epigallocatechin gallate (EGCG) is a well-studied polyphenol with antioxidant effects. Since EGCG has low solubility and stability, many researchers have modified EGCG residues to ameliorate these problems. A novel EGCG derivative, EGCG-5'- O -α-glucopyranoside (EGCG-5'Glu), was synthesized, and its characteristics were investigated. EGCG-5'Glu showed antioxidant effects in cell and cell-free systems. Under SNP-derived radical exposure, EGCG-5'Glu decreased nitric oxide (NO) production, and recovered ROS-mediated cell viability. Moreover, EGCG-5'Glu regulated apoptotic pathways (caspases) and cell survival molecules (phosphoinositide 3-kinase (PI3K) and phosphoinositide-dependent kinase 1 (PDK1)). In another radical-induced condition, ultraviolet B (UVB) irradiation, EGCG-5'Glu protected cells from UVB and regulated the PI3K/PDK1/AKT pathway. Next, the proliferative effect of EGCG-5'Glu was examined. EGCG-5'Glu increased cell proliferation by modulating nuclear factor (NF)-κB activity. EGCG-5'Glu protects and repairs cells from external damage via its antioxidant effects. These results suggest that EGCG-5'Glu could be used as a cosmetics ingredient or dietary supplement.

Edaravone Protected Human Brain Microvascular Endothelial Cells from Methylglyoxal-Induced Injury by Inhibiting AGEs/RAGE/Oxidative Stress

PubMed Central

Li, Wenlu; Xu, Hongjiao; Hu, Yangmin; He, Ping; Ni, Zhenzhen; Xu, Huimin; Zhang, Zhongmiao; Dai, Haibin

2013-01-01

Subjects with diabetes experience an increased risk of cerebrovascular disease and stroke compared with nondiabetic age-matched individuals. Increased formation of reactive physiological dicarbonyl compound methylglyoxal (MGO) seems to be implicated in the development of diabetic vascular complication due to its protein glycation and oxidative stress effect. Edaravone, a novel radical scavenger, has been reported to display the advantageous effects on ischemic stroke both in animals and clinical trials; however, little is known about whether edaravone has protective effects on diabetic cerebrovascular injury. Using cultured human brain microvascular endothelial cells (HBMEC), protective effects of edaravone on MGO and MGO enhancing oxygen-glucose deprivation (OGD) induced injury were investigated. Cell injury was measured by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) formation, cell account, lactate dehydrogenase (LDH) release and Rhodamine 123 staining. Advanced glycation end-products (AGEs) formation and receptor for advanced glycation end-products (RAGE) expression were measured by western blotting. Cellular oxidative stress was measured by reactive oxygen species (ROS) release. Treatment of MGO for 24 h significantly induced HBMEC injury, which was inhibited by pretreatment of edaravone from 10–100 µmol/l. What’s more, treatment of MGO enhanced AGEs accumulation, RAGE expression and ROS release in the cultured HBMEC, which were inhibited by 100 µmol/l edaravone. Finally, treatment of MGO for 24 h and then followed by 3 h OGD insult significantly enhanced cell injury when compared with OGD insult only, which was also protected by 100 µmol/l edaravone. Thus, edaravone protected HBMEC from MGO and MGO enhancing OGD-induced injury by inhibiting AGEs/RAGE/oxidative stress. PMID:24098758

Protective effect and molecular mechanism of liquiritin on oxybuprocaine-induced apoptosis of human corneal endothelial cells

PubMed Central

Li, Dan; Zhang, Peng

2018-01-01

This study was designed to investigate the protective effect and possible molecular mechanism of liquiritin on oxybuprocaine-induced apoptosis of human corneal endothelial cells (HCECs). In this study, the effect of oxybuprocaine on the proliferation of HCEC-12 was detected using cell counting kit-8 (CCK-8). The inductive effect of oxybuprocaine on HCEC-12 apoptosis and protective effect of liquiritin against oxybuprocaine-induced HCEC-12 apoptosis were tested by Annexin V/propidium iodide (PI) staining and flow cytometry. The production of reactive oxygen species (ROS) was analyzed by 2,7-dichlorodi-hydrofluorescein diacetate (DCFH-DA) staining and fluorescent-activated cell sorting (FACS), and the expression of nuclear factor-κB (NF-κB) p65 and apoptosis-related proteins, caspase-3 and Bax, was determined by western blot analysis. Our results show that liquiritin resisted the inhibitory effect of oxybuprocaine on the proliferation of HCEC-12, and cell activity had the most significant increase in pretreatment with liquiritin group in the concentration of 8 mg/ml; compared with that in oxybuprocaine group. Apoptosis in pretreatment with liquiritin was distinctly decreased and liquiritin resisted the production of ROS in HCEC-12 induced by oxybuprocaine. Investigation of molecular mechanism revealed that the pretreatment with liquiritin and pyrrolidinedithiocarbamic acid (PDTC) obviously blocked the expression of NF-κB p65 in nuclear protein increased by oxybuprocaine and the expression levels of total proteins, caspase-3 and Bax.Moreover, tumor necrosis factor-α (TNF-α) blocked the inhibitory effect of liquiritin on the expression of NF-κB p65 in nuclear protein and total proteins, caspase-3 and Bax, thus obstructing the protective effect of liquiritin on corneal epithelial cells. The results of this study indicated that liquiritin reduces the expression of apoptosis protein and increases the expression of anti-apoptotic protein through inhibiting NF-κB signal pathway, thus resisting HCEC-12 apoptosis induced by oxybuprocaine. PMID:29545865

Protective effect and molecular mechanism of liquiritin on oxybuprocaine-induced apoptosis of human corneal endothelial cells.

PubMed

Li, Dan; Zhang, Peng

2018-04-01

This study was designed to investigate the protective effect and possible molecular mechanism of liquiritin on oxybuprocaine-induced apoptosis of human corneal endothelial cells (HCECs). In this study, the effect of oxybuprocaine on the proliferation of HCEC-12 was detected using cell counting kit-8 (CCK-8). The inductive effect of oxybuprocaine on HCEC-12 apoptosis and protective effect of liquiritin against oxybuprocaine-induced HCEC-12 apoptosis were tested by Annexin V/propidium iodide (PI) staining and flow cytometry. The production of reactive oxygen species (ROS) was analyzed by 2,7-dichlorodi-hydrofluorescein diacetate (DCFH-DA) staining and fluorescent-activated cell sorting (FACS), and the expression of nuclear factor-κB (NF-κB) p65 and apoptosis-related proteins, caspase-3 and Bax, was determined by western blot analysis. Our results show that liquiritin resisted the inhibitory effect of oxybuprocaine on the proliferation of HCEC-12, and cell activity had the most significant increase in pretreatment with liquiritin group in the concentration of 8 mg/ml; compared with that in oxybuprocaine group. Apoptosis in pretreatment with liquiritin was distinctly decreased and liquiritin resisted the production of ROS in HCEC-12 induced by oxybuprocaine. Investigation of molecular mechanism revealed that the pretreatment with liquiritin and pyrrolidinedithiocarbamic acid (PDTC) obviously blocked the expression of NF-κB p65 in nuclear protein increased by oxybuprocaine and the expression levels of total proteins, caspase-3 and Bax.Moreover, tumor necrosis factor-α (TNF-α) blocked the inhibitory effect of liquiritin on the expression of NF-κB p65 in nuclear protein and total proteins, caspase-3 and Bax, thus obstructing the protective effect of liquiritin on corneal epithelial cells. The results of this study indicated that liquiritin reduces the expression of apoptosis protein and increases the expression of anti-apoptotic protein through inhibiting NF-κB signal pathway, thus resisting HCEC-12 apoptosis induced by oxybuprocaine.

Accumulation of Poly(3-hydroxybutyrate) Helps Bacterial Cells to Survive Freezing

PubMed Central

Krzyzanek, Vladislav; Mravec, Filip; Hrubanova, Kamila; Samek, Ota; Kucera, Dan; Benesova, Pavla; Marova, Ivana

2016-01-01

Accumulation of polyhydroxybutyrate (PHB) seems to be a common metabolic strategy adopted by many bacteria to cope with cold environments. This work aimed at evaluating and understanding the cryoprotective effect of PHB. At first a monomer of PHB, 3-hydroxybutyrate, was identified as a potent cryoprotectant capable of protecting model enzyme (lipase), yeast (Saccharomyces cerevisiae) and bacterial cells (Cupriavidus necator) against the adverse effects of freezing-thawing cycles. Further, the viability of the frozen–thawed PHB accumulating strain of C. necator was compared to that of the PHB non-accumulating mutant. The presence of PHB granules in cells was revealed to be a significant advantage during freezing. This might be attributed to the higher intracellular level of 3-hydroxybutyrate in PHB accumulating cells (due to the action of parallel PHB synthesis and degradation, the so-called PHB cycle), but the cryoprotective effect of PHB granules seems to be more complex. Since intracellular PHB granules retain highly flexible properties even at extremely low temperatures (observed by cryo-SEM), it can be expected that PHB granules protect cells against injury from extracellular ice. Finally, thermal analysis indicates that PHB-containing cells exhibit a higher rate of transmembrane water transport, which protects cells against the formation of intracellular ice which usually has fatal consequences. PMID:27315285

A fully integrated new paradigm for lithium’s mode of action – lithium utilizes latent cellular fail-safe mechanisms

PubMed Central

van Woerkom, Arthur Ernst

2017-01-01

It is proposed that lithium’s therapeutic effects occur indirectly by augmenting a cascade of protective “fail-safe” pathways pre-configured to activate in response to a dangerous low cell [Mg++] situation, eg, posttraumatic brain injury, alongside relative cell adenosine triphosphate depletion. Lithium activates cell protection, as it neatly mimics a lowered intracellular [Mg++] level. PMID:28203080

Adjuvant-enhanced CD4 T Cell Responses are Critical to Durable Vaccine Immunity.

PubMed

Martins, Karen A O; Cooper, Christopher L; Stronsky, Sabrina M; Norris, Sarah L W; Kwilas, Steven A; Steffens, Jesse T; Benko, Jacqueline G; van Tongeren, Sean A; Bavari, Sina

2016-01-01

Protein-based vaccines offer a safer alternative to live-attenuated or inactivated vaccines but have limited immunogenicity. The identification of adjuvants that augment immunogenicity, specifically in a manner that is durable and antigen-specific, is therefore critical for advanced development. In this study, we use the filovirus virus-like particle (VLP) as a model protein-based vaccine in order to evaluate the impact of four candidate vaccine adjuvants on enhancing long term protection from Ebola virus challenge. Adjuvants tested include poly-ICLC (Hiltonol), MPLA, CpG 2395, and alhydrogel. We compared and contrasted antibody responses, neutralizing antibody responses, effector T cell responses, and T follicular helper (Tfh) cell frequencies with each adjuvant's impact on durable protection. We demonstrate that in this system, the most effective adjuvant elicits a Th1-skewed antibody response and strong CD4 T cell responses, including an increase in Tfh frequency. Using immune-deficient animals and adoptive transfer of serum and cells from vaccinated animals into naïve animals, we further demonstrate that serum and CD4 T cells play a critical role in conferring protection within effective vaccination regimens. These studies inform on the requirements of long term immune protection, which can potentially be used to guide screening of clinical-grade adjuvants for vaccine clinical development.

Inhibition of amyloid β aggregation and protective effect on SH-SY5Y cells by triterpenoid saponins from the cactus Polaskia chichipe.

PubMed

Fujihara, Koji; Koike, Shin; Ogasawara, Yuki; Takahashi, Kunio; Koyama, Kiyotaka; Kinoshita, Kaoru

2017-07-01

Alzheimer's disease (AD) destroys brain function, especially in the hippocampus, and is a social problem worldwide. A major pathogenesis of AD is related to the accumulation of amyloid beta (Aβ) peptides, resulting in neuronal cell death in the brain. Here, we isolated four saponins (1-4) and elucidated their structures from 1D and 2D NMR and HRFABMS spectral data. The structures of 1 and 2 were determined as new saponins which have cochalic acid as the aglycon, and 3 was determined as a new saponin with oleanolic acid as the aglycon. Compound 4 was confirmed as the known saponin chikusetsusaponin V (=ginsenoside R 0 ). Isolated saponins (1-4) and six previously reported saponins (5-10) were tested for their inhibitory effects of Aβ aggregation and their protective effects on SH-SY5Y cells against Aβ-associated toxicity. As the results, compounds 3 and 4 showed inhibitory effect of Aβ aggregation and compounds 5-8 exerted the protective effects on SH-SY5Y cells against Aβ-associated toxicity. Copyright © 2017 Elsevier Ltd. All rights reserved.

EXPRESSION OF INDUCIBLE HSP70 ENHANCES THE PROLIFERATION OF MCF-7 BREAST CANCER CELLS AND PROTECTS AGAINST THE CYTOTOXIC EFFECTS OF HYPERTHERMIA

EPA Science Inventory

Heat shock proteins (HSPs) are ubiquitous proteins that are induced following exposure to sub-lethal heat shock, are highly conserved during evolution and protect cells from damage through their function as molecular chaperones. Some cancers demonstrate elevated levels of Hsp70 ...

The new approaches to preservation of graft cell integrity in preservation for transplantation.

PubMed

Gewartowska, Magdalena; Olszewski, Waldemar L

2005-01-01

Restoration of cell plasma membrane integrity after injury is essential for the survival of animal cells. In case of graft preservation or during chemotherapy in cancer, cell membrane integrity and the process of its repair are disrupted. Cytoprotective substances are important in such cases, as well as in other diseases, for example in myocardial infarction, acute insults and in chronic neurodegenerative diseases. Hyperosmolarity is a condition in which cell membrane stability may be damaged in vivo but preserved in the in vitro conditions. Hypertonicity causes water leaving from cells by osmosis, decreasing cell volume and increasing of intracellular ionic strength. High intracellular ionic strength perturbs cellular function by decreasing the rates of biochemical reaction. We review the new experimentally studied cytoprotective substances and their application in cell membrane protection. Moreover, we present our data on the effects of hyperosmolarity and its protective effect on cell internal structure.

Sulforaphane protects rodent retinas against ischemia-reperfusion injury through the activation of the Nrf2/HO-1 antioxidant pathway.

PubMed

Pan, Hong; He, Meihua; Liu, Ruixing; Brecha, Nicholas C; Yu, Albert Cheung Hoi; Pu, Mingliang

2014-01-01

Retinal ischemia-reperfusion (I/R) injury induces oxidative stress, leukocyte infiltration, and neuronal cell death. Sulforaphane (SF), which can be obtained in cruciferous vegetables such as broccoli, exerts protective effects in response to oxidative stress in various tissues. These effects can be initiated through nuclear factor E2-related factor 2 (Nrf2)-mediated induction of heme oxygenase-1 (HO-1). This investigation was designed to elucidate the neural protective mechanisms of SF in the retinal I/R rat model. Animals were intraperitoneally (i.p.) injected with SF (12.5 mg/kg) or vehicle (corn oil) once a day for 7 consecutive days. Then, retinal I/R was made by elevating the intraocular pressure (IOP) to 130 mmHg for 1 h. To determine if HO-1 was involved in the Nrf2 antioxidant pathway, rats were subjected to protoporphyrin IX zinc (II) (ZnPP, 30 mg/kg, i.p.) treatments at 24 h before retinal ischemia. The neuroprotective effects of SF were assessed by determining the morphology of the retina, counting the infiltrating inflammatory cells and the surviving retinal ganglion cells (RGCs) and amacrine cells, and measuring apoptosis in the retinal layers. The expression of Nrf2 and HO-1 was studied by immunofluorescence analysis and western blotting. I/R induced a marked increase of ROS generation, caused pronounced inflammation, increased the apoptosis of RGCs and amacrine cells and caused the thinning of the inner retinal layer (IRL), and these effects were diminished or abolished by SF pretreatment. Meanwhile, SF pretreatment significantly elevated the nuclear accumulation of Nrf2 and the level of HO-1 expression in the I/R retinas; however, ZnPP reversed the protective effects of SF on I/R retinas. Together, we offer direct evidence that SF had protective effects on I/R retinas, which could be attributed, at least in part, to the activation of the Nrf2/HO-1 antioxidant pathway.

Sulforaphane Protects Rodent Retinas against Ischemia-Reperfusion Injury through the Activation of the Nrf2/HO-1 Antioxidant Pathway

PubMed Central

Liu, Ruixing; Brecha, Nicholas C.; Yu, Albert Cheung Hoi; Pu, Mingliang

2014-01-01

Retinal ischemia-reperfusion (I/R) injury induces oxidative stress, leukocyte infiltration, and neuronal cell death. Sulforaphane (SF), which can be obtained in cruciferous vegetables such as broccoli, exerts protective effects in response to oxidative stress in various tissues. These effects can be initiated through nuclear factor E2-related factor 2 (Nrf2)-mediated induction of heme oxygenase-1 (HO-1). This investigation was designed to elucidate the neural protective mechanisms of SF in the retinal I/R rat model. Animals were intraperitoneally (i.p.) injected with SF (12.5 mg/kg) or vehicle (corn oil) once a day for 7 consecutive days. Then, retinal I/R was made by elevating the intraocular pressure (IOP) to 130 mmHg for 1 h. To determine if HO-1 was involved in the Nrf2 antioxidant pathway, rats were subjected to protoporphyrin IX zinc (II) (ZnPP, 30 mg/kg, i.p.) treatments at 24 h before retinal ischemia. The neuroprotective effects of SF were assessed by determining the morphology of the retina, counting the infiltrating inflammatory cells and the surviving retinal ganglion cells (RGCs) and amacrine cells, and measuring apoptosis in the retinal layers. The expression of Nrf2 and HO-1 was studied by immunofluorescence analysis and western blotting. I/R induced a marked increase of ROS generation, caused pronounced inflammation, increased the apoptosis of RGCs and amacrine cells and caused the thinning of the inner retinal layer (IRL), and these effects were diminished or abolished by SF pretreatment. Meanwhile, SF pretreatment significantly elevated the nuclear accumulation of Nrf2 and the level of HO-1 expression in the I/R retinas; however, ZnPP reversed the protective effects of SF on I/R retinas. Together, we offer direct evidence that SF had protective effects on I/R retinas, which could be attributed, at least in part, to the activation of the Nrf2/HO-1 antioxidant pathway. PMID:25470382

Activation of the Nrf2/HO-1 Antioxidant Pathway Contributes to the Protective Effects of Lycium Barbarum Polysaccharides in the Rodent Retina after Ischemia-Reperfusion-Induced Damage

PubMed Central

Chang, Raymond Chuen-Chung; So, Kwok-Fai; Brecha, Nicholas C.; Pu, Mingliang

2014-01-01

Lycium barbarum polysaccharides (LBP), extracts from the wolfberries, are protective to retina after ischemia-reperfusion (I/R). The antioxidant response element (ARE)–mediated antioxidant pathway plays an important role in maintaining the redox status of the retina. Heme oxygenase-1 (HO-1), combined with potent AREs in its promoter, is a highly effective therapeutic target for the protection against neurodegenerative diseases, including I/R-induced retinal damage. The aim of our present study was to investigate whether the protective effect of LBP after I/R damage was mediated via activation of the Nrf2/HO-1-antioxidant pathway in the retina. Retinal I/R was induced by an increase in intraocular pressure to 130 mm Hg for 60 minutes. Prior to the induction of ischemia, rats were orally treated with either vehicle (PBS) or LBP (1 mg/kg) once a day for 1 week. For specific experiments, zinc protoporphyrin (ZnPP, 20 mg/kg), an HO-1 inhibitor, was intraperitoneally administered at 24 h prior to ischemia. The protective effects of LBP were evaluated by quantifying ganglion cell and amacrine cell survival, and by measuring cell apoptosis in the retinal layers. In addition, HO-1 expression was examined using Western blotting and immunofluorescence analyses. Cytosolic and nuclear Nrf2 was measured using immunofluorescent staining. LBP treatment significantly increased Nrf2 nuclear accumulation and HO-1 expression in the retina after I/R injury. Increased apoptosis and a decrease in the number of viable cells were observed in the ganglion cell layer (GCL) and inner nuclear layer (INL) in the I/R retina, which were reversed by LBP treatment. The HO-1 inhibitor, ZnPP, diminished the LBP treatment-induced protective effects in the retina after I/R. Taken together, these results suggested that LBP partially exerted its beneficial neuroprotective effects via the activation of Nrf2 and an increase in HO-1 protein expression. PMID:24400114

Extracellular vesicles from human-induced pluripotent stem cell-derived mesenchymal stromal cells (hiPSC-MSCs) protect against renal ischemia/reperfusion injury via delivering specificity protein (SP1) and transcriptional activating of sphingosine kinase 1 and inhibiting necroptosis.

PubMed

Yuan, Xiaodong; Li, Dawei; Chen, Xiaosong; Han, Conghui; Xu, Longmei; Huang, Tao; Dong, Zhen; Zhang, Ming

2017-12-11

Renal ischemia-reperfusion is a main cause of acute kidney injury (AKI), which is associated with high mortality. Here we show that extracellular vesicles (EVs) secreted from hiPSC-MSCs play a critical role in protection against renal I/R injury. hiPSC-MSCs-EVs can fuse with renal cells and deliver SP1 into target cells, subsequently active SK1 expression and increase S1P formation. Chromatin immunoprecipitation (ChIP) analyses and luciferase assay were used to confirm SP1 binds directly to the SK1 promoter region and promote promoter activity. Moreover, SP1 inhibition (MIT) or SK1 inhibition (SKI-II) completely abolished the renal protective effect of hiPSC-MSCs-EVs in rat I/R injury mode. However, pre-treatment of necroptosis inhibitor Nec-1 showed no difference with the administration of hiPSC-MSCs-EVs only. We then generated an SP1 knockout hiPSC-MSC cell line by CRISPR/Cas9 system and found that SP1 knockout failed to show the protective effect of hiPSC-MSCs-EVs unless restoring the level of SP1 by Ad-SP1 in vitro and in vivo. In conclusion, this study describes an anti-necroptosis effect of hiPSC-MSCs-EVs against renal I/R injury via delivering SP1 into target renal cells and intracellular activating the expression of SK1 and the generation of S1P. These findings suggest a novel mechanism for renal protection against I/R injury, and indicate a potential therapeutic approach for a variety of renal diseases and renal transplantation.

Protective Effects of Resveratrol against UVA-Induced Damage in ARPE19 Cells

PubMed Central

Chan, Chi-Ming; Huang, Cheng-Hua; Li, Hsin-Ju; Hsiao, Chien-Yu; Su, Ching-Chieh; Lee, Pei-Lan; Hung, Chi-Feng

2015-01-01

Ultraviolet radiation, especially UVA, can penetrate the lens, reach the retina, and induce oxidative stress to retinal pigment epithelial (RPE) cells. Even though it is weakly absorbed by protein and DNA, it may trigger the production of reactive oxygen species (ROS) and generate oxidative injury; oxidative injury to the retinal pigment epithelium has been implicated to play a contributory role in age-related macular degeneration (AMD). Studies showed that resveratrol, an abundant and active component of red grapes, can protect several cell types from oxidative stress. In this study, adult RPE cells being treated with different concentrations of resveratrol were used to evaluate the protective effect of resveratrol on RPE cells against UVA-induced damage. Cell viability assay showed that resveratrol reduced the UVA-induced decrease in RPE cell viability. Through flow cytometry analysis, we found that the generation of intracellular H2O2 induced by UVA irradiation in RPE cells could be suppressed by resveratrol in a concentration-dependent manner. Results of Western blot analysis demonstrated that resveratrol lowered the activation of UVA-induced extracellular signal-regulated kinase, c-jun-NH2 terminal kinase and p38 kinase in RPE cells. In addition, there was also a reduction in UVA-induced cyclooxygenase-2 (COX-2) expression in RPE cells pretreated with resveratrol. Our observations suggest that resveratrol is effective in preventing RPE cells from being damaged by UVA radiation, and is worth considering for further development as a chemoprotective agent for the prevention of early AMD. PMID:25775159

Protective effects of resveratrol against UVA-induced damage in ARPE19 cells.

PubMed

Chan, Chi-Ming; Huang, Cheng-Hua; Li, Hsin-Ju; Hsiao, Chien-Yu; Su, Ching-Chieh; Lee, Pei-Lan; Hung, Chi-Feng

2015-03-12

Ultraviolet radiation, especially UVA, can penetrate the lens, reach the retina, and induce oxidative stress to retinal pigment epithelial (RPE) cells. Even though it is weakly absorbed by protein and DNA, it may trigger the production of reactive oxygen species (ROS) and generate oxidative injury; oxidative injury to the retinal pigment epithelium has been implicated to play a contributory role in age-related macular degeneration (AMD). Studies showed that resveratrol, an abundant and active component of red grapes, can protect several cell types from oxidative stress. In this study, adult RPE cells being treated with different concentrations of resveratrol were used to evaluate the protective effect of resveratrol on RPE cells against UVA-induced damage. Cell viability assay showed that resveratrol reduced the UVA-induced decrease in RPE cell viability. Through flow cytometry analysis, we found that the generation of intracellular H2O2 induced by UVA irradiation in RPE cells could be suppressed by resveratrol in a concentration-dependent manner. Results of Western blot analysis demonstrated that resveratrol lowered the activation of UVA-induced extracellular signal-regulated kinase, c-jun-NH2 terminal kinase and p38 kinase in RPE cells. In addition, there was also a reduction in UVA-induced cyclooxygenase-2 (COX-2) expression in RPE cells pretreated with resveratrol. Our observations suggest that resveratrol is effective in preventing RPE cells from being damaged by UVA radiation, and is worth considering for further development as a chemoprotective agent for the prevention of early AMD.

Cyanidin-3-O-glucoside inhibits NF-kB signalling in intestinal epithelial cells exposed to TNF-α and exerts protective effects via Nrf2 pathway activation.

PubMed

Ferrari, Daniela; Speciale, Antonio; Cristani, Mariateresa; Fratantonio, Deborah; Molonia, Maria Sofia; Ranaldi, Giulia; Saija, Antonella; Cimino, Francesco

2016-12-15

Chronic intestinal inflammatory disorders, such as Inflammatory Bowel Diseases (IBDs), are characterized by excessive release of proinflammatory mediators, intestinal barrier dysfunction and excessive activation of NF-kB cascade. Previous studies shown that TNF-α plays a central role in intestinal inflammation of IBDs and supported beneficial effects of flavonoids against chronic inflammatory diseases. In this study, we employed an in vitro model of acute intestinal inflammation using intestinal Caco-2 cells exposed to TNF-α. The protective effects of cyanidin-3-glucoside (C3G), an anthocyanin widely distributed in mediterranean diet, were then evaluated. Caco-2 cells exposure to TNF-α activated NF-kB proinflammatory pathway and induced IL6 and COX-2 expression. Cells pretreatment for 24h with C3G (20-40μM) prevented TNF-α-induced changes, and improved intracellular redox status. Our results demonstrated that C3G, also without any kind of stimulus, increased the translocation of the transcription factor Nrf2 into the nucleus so activating antioxidant and detoxifying genes. In conclusion, C3G exhibited protective effects through the inhibition of NF-kB signalling in Caco-2 cells and these beneficial effects appear to be due to its ability to activate cellular protective responses modulated by Nrf2. These data suggest that anthocyanins could contribute, as complementary or preventive approaches, to the management of chronic inflammatory diseases. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Interaction of Saccharomyces boulardii with Salmonella enterica Serovar Typhimurium Protects Mice and Modifies T84 Cell Response to the Infection

PubMed Central

Martins, Flaviano S.; Dalmasso, Guillaume; Arantes, Rosa M. E.; Doye, Anne; Lemichez, Emmanuel; Lagadec, Patricia; Imbert, Veronique; Peyron, Jean-François; Rampal, Patrick; Nicoli, Jacques R.; Czerucka, Dorota

2010-01-01

Background Salmonella pathogenesis engages host cells in two-way biochemical interactions: phagocytosis of bacteria by recruitment of cellular small GTP-binding proteins induced by the bacteria, and by triggering a pro-inflammatory response through activation of MAPKs and nuclear translocation of NF-κB. Worldwide interest in the use of functional foods containing probiotic bacteria for health promotion and disease prevention has increased significantly. Saccharomyces boulardii is a non-pathogenic yeast used as a probiotic in infectious diarrhea. Methodology/Principal Findings In this study, we reported that S. boulardii (Sb) protected mice from Salmonella enterica serovar Typhimurium (ST)-induced death and prevented bacterial translocation to the liver. At a molecular level, using T84 human colorectal cancer cells, we demonstrate that incubation with Sb before infection totally abolished Salmonella invasion. This correlates with a decrease of activation of Rac1. Sb preserved T84 barrier function and decreased ST-induced IL-8 synthesis. This anti-inflammatory effect was correlated with an inhibitory effect of Sb on ST-induced activation of the MAPKs ERK1/2, p38 and JNK as well as on activation of NF-κB. Electron and confocal microscopy experiments showed an adhesion of bacteria to yeast cells, which could represent one of the mechanisms by which Sb exerts its protective effects. Conclusions Sb shows modulating effects on permeability, inflammation, and signal transduction pathway in T84 cells infected by ST and an in vivo protective effect against ST infection. The present results also demonstrate that Sb modifies invasive properties of Salmonella. PMID:20111723

The protective effect of curcumin in Olfactory Ensheathing Cells exposed to hypoxia.

PubMed

Bonfanti, Roberta; Musumeci, Teresa; Russo, Cristina; Pellitteri, Rosalia

2017-02-05

Curcumin, a phytochemical component derived from the rhizomes of Curcuma longa, has shown a great variety of pharmacological activities, such as anti-inflammatory, anti-tumor, anti-depression and anti-oxidant activity. Therefore, in the last years it has been used as a therapeutic agent since it confers protection in different neurodegenerative diseases, cerebral ischemia and excitotoxicity. Olfactory Ensheathing Cells (OECs) are glial cells of the olfactory system. They are able to secrete several neurotrophic growth factors, promote axonal growth and support the remyelination of damaged axons. OEC transplantation has emerged as a possible experimental therapy to induce repair of spinal cord injury, even if the functional recovery is still limited. Since hypoxia is a secondary effect in spinal cord injury, this in vitro study investigates the protective effect of curcumin in OECs exposed to hypoxia. Primary OECs were obtained from neonatal rat olfactory bulbs and placed both in normal and hypoxic conditions. Furthermore, some cells were grown with basic Fibroblast Growth Factor (bFGF) and/or curcumin at different concentration and times. The results obtained through immunocytochemical procedures and MTT test show that curcumin stimulates cell viability in OECs grown in normal and hypoxic conditions. Furthermore, the synergistic effect of curcumin and bFGF is the most effective exerting protection on OECs. Since spinal cord injury is often accompanied by secondary insults, such as ischemia or hypoxia, our results suggest that curcumin in combination with bFGF might be considered a possible approach for restoration in injuries. Copyright © 2016 Elsevier B.V. All rights reserved.

Progranulin, a Major Secreted Protein of Mouse Adipose-Derived Stem Cells, Inhibits Light-Induced Retinal Degeneration

PubMed Central

Tsuruma, Kazuhiro; Yamauchi, Mika; Sugitani, Sou; Otsuka, Tomohiro; Ohno, Yuta; Nagahara, Yuki; Ikegame, Yuka; Shimazawa, Masamitsu; Yoshimura, Shinichi; Iwama, Toru

2014-01-01

Adipose tissue stromal vascular fraction contains mesenchymal stem cells, which show protective effects when administered to damaged tissues, mainly through secreted trophic factors. We examined the protective effects of adipose-derived stem cells (ASCs) and ASC-conditioned medium (ASC-CM) against retinal damage and identified the neuroprotective factors in ASC-CM. ASCs and mature adipocytes were isolated from mouse subcutaneous tissue. ASCs were injected intravitreally in a mouse model of light-induced retinal damage, and ASC injection recovered retinal function as measured by electroretinogram and inhibited outer nuclear layer, thinning, without engraftment of ASCs. ASC-CM and mature adipocyte-conditioned medium were collected after 72 hours of culture. In vitro, H2O2- and light-induced cell death was reduced in a photoreceptor cell line with ASC-CM but not with mature adipocyte-conditioned medium. In vivo, light-induced photoreceptor damage was evaluated by measurement of outer nuclear layer thickness at 5 days after light exposure and by electroretinogram recording. ASC-CM significantly inhibited photoreceptor degeneration and retinal dysfunction after light exposure. Progranulin was identified as a major secreted protein of ASCs that showed protective effects against retinal damage in vitro and in vivo. Furthermore, progranulin phosphorylated extracellular signal-regulated kinase, cAMP response element binding protein, and hepatocyte growth factor receptor, and protein kinase C signaling pathways were involved in the protective effects of progranulin. These findings suggest that ASC-CM and progranulin have neuroprotective effects in the light-induced retinal-damage model. Progranulin may be a potential target for the treatment of the degenerative diseases of the retina. PMID:24233842

Progranulin, a major secreted protein of mouse adipose-derived stem cells, inhibits light-induced retinal degeneration.

PubMed

Tsuruma, Kazuhiro; Yamauchi, Mika; Sugitani, Sou; Otsuka, Tomohiro; Ohno, Yuta; Nagahara, Yuki; Ikegame, Yuka; Shimazawa, Masamitsu; Yoshimura, Shinichi; Iwama, Toru; Hara, Hideaki

2014-01-01

Adipose tissue stromal vascular fraction contains mesenchymal stem cells, which show protective effects when administered to damaged tissues, mainly through secreted trophic factors. We examined the protective effects of adipose-derived stem cells (ASCs) and ASC-conditioned medium (ASC-CM) against retinal damage and identified the neuroprotective factors in ASC-CM. ASCs and mature adipocytes were isolated from mouse subcutaneous tissue. ASCs were injected intravitreally in a mouse model of light-induced retinal damage, and ASC injection recovered retinal function as measured by electroretinogram and inhibited outer nuclear layer, thinning, without engraftment of ASCs. ASC-CM and mature adipocyte-conditioned medium were collected after 72 hours of culture. In vitro, H2O2- and light-induced cell death was reduced in a photoreceptor cell line with ASC-CM but not with mature adipocyte-conditioned medium. In vivo, light-induced photoreceptor damage was evaluated by measurement of outer nuclear layer thickness at 5 days after light exposure and by electroretinogram recording. ASC-CM significantly inhibited photoreceptor degeneration and retinal dysfunction after light exposure. Progranulin was identified as a major secreted protein of ASCs that showed protective effects against retinal damage in vitro and in vivo. Furthermore, progranulin phosphorylated extracellular signal-regulated kinase, cAMP response element binding protein, and hepatocyte growth factor receptor, and protein kinase C signaling pathways were involved in the protective effects of progranulin. These findings suggest that ASC-CM and progranulin have neuroprotective effects in the light-induced retinal-damage model. Progranulin may be a potential target for the treatment of the degenerative diseases of the retina.

Isorhynchophylline Protects PC12 Cells Against Beta-Amyloid-Induced Apoptosis via PI3K/Akt Signaling Pathway

PubMed Central

Xian, Yan-Fang; Lin, Zhi-Xiu; Mao, Qing-Qiu; Chen, Jian-Nan; Su, Zi-Ren; Lai, Xiao-Ping; Ip, Paul Siu-Po

2013-01-01

The neurotoxicity of amyloid-β (Aβ) has been implicated as a critical cause of Alzheimer's disease. Isorhynchophylline (IRN), an oxindole alkaloid isolated from Uncaria rhynchophylla, exerts neuroprotective effect against Aβ 25–35-induced neurotoxicity in vitro. However, the exact mechanism for its neuroprotective effect is not well understood. The present study aimed to investigate the molecular mechanisms underlying the protective action of IRN against Aβ 25–35-induced neurotoxicity in cultured rat pheochromocytoma (PC12) cells. Pretreatment with IRN significantly increased the cell viability, inhibited the release of lactate dehydrogenase and the extent of DNA fragmentation in Aβ 25–35-treated cells. IRN treatment was able to enhance the protein levels of phosphorylated Akt (p-Akt) and glycogen synthase kinase-3β (p-GSK-3β). Lithium chloride blocked Aβ 25–35-induced cellular apoptosis in a similar manner as IRN, suggesting that GSK-3β inhibition was involved in neuroprotective action of IRN. Pretreatment with LY294002 completely abolished the protective effects of IRN. Furthermore, IRN reversed Aβ 25–35-induced attenuation in the level of phosphorylated cyclic AMP response element binding protein (p-CREB) and the effect of IRN could be blocked by the PI3K inhibitor. These experimental findings unambiguously suggested that the protective effect of IRN against Aβ 25–35-induced apoptosis in PC12 cells was associated with the enhancement of p-CREB expression via PI3K/Akt/GSK-3β signaling pathway. PMID:24319473

Agent selection and protective effects during single droplet drying of bacteria.

PubMed

Khem, Sarim; Woo, Meng Wai; Small, Darryl M; Chen, Xiao Dong; May, Bee K

2015-01-01

The protective mechanisms of whey protein isolate (WPI), trehalose, lactose, and skim milk on Lactobacillus plantarum A17 during convective droplet drying has been explored. A single droplet drying technique was used to monitor cell survival, droplet temperature and corresponding changes in mass. WPI and skim milk provided the highest protection amongst the materials tested. In situ analysis of the intermediate stage of drying revealed that for WPI and skim milk, crust formation reduces the rate of sudden temperature increase thereby imparting less stress on the cells. Irreversible denaturation of the WPI components might have also contributed to the protection of the cells. Skim milk, however, 'loses' the protective behaviour towards the latter stages of drying. This indicates that the concentration of the WPI components could be another possible factor determining the sustained protective behaviour during the later stages of drying when the moisture content is low. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of propofol on hypoxia re-oxygenation induced neuronal cell damage in vitro*.

PubMed

Huang, Y; Zitta, K; Bein, B; Scholz, J; Steinfath, M; Albrecht, M

2013-01-01

Propofol may protect neuronal cells from hypoxia re-oxygenation injury, possibly via an antioxidant actions under hypoxic conditions. This study investigated the molecular effects of propofol on hypoxia-induced cell damage using a neuronal cell line. Cultured human IMR-32 cells were exposed to propofol (30 μm) and biochemical and molecular approaches were used to assess cellular effects. Propofol significantly reduced hypoxia-mediated increases in lactate dehydrogenase, a marker of cell damage (mean (SD) for normoxia: 0.39 (0.07) a.u.; hypoxia: 0.78 (0.21) a.u.; hypoxia+propofol: 0.44 (0.17) a.u.; normoxia vs hypoxia, p<0.05; hypoxia vs hypoxia+propofol, p<0.05), reactive oxygen species and hydrogen peroxide. Propofol also diminished the morphological signs of cell damage. Increased amounts of catalase, which degrades hydrogen peroxide, were detected under hypoxic conditions. Propofol decreased the amount of catalase produced, but increased its enzymatic activity. Propofol protects neuronal cells from hypoxia re-oxygenation injury, possibly via a combined direct antioxidant effect along with induced cellular antioxidant mechanisms. Anaesthesia © 2012 The Association of Anaesthetists of Great Britain and Ireland.

Protective Effects of Hydrogen Sulfide in Hypoxic Human Umbilical Vein Endothelial Cells: A Possible Mitochondria-Dependent Pathway

PubMed Central

Shen, Yaqi; Guo, Wei; Wang, Zhijun; Zhang, Yuchen; Zhong, Liangjie; Zhu, Yizhun

2013-01-01

The aim of the study was to investigate the protective effects of sodium hydrosulfide (NaHS), a H2S donor, against hypoxia-induced injury in human umbilical vein endothelial cells (HUVECs) and also to look into the possible mechanisms by which H2S exerts this protective effect. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and scratch wound healing assay were chosen to measure the cell viability and migration-promoting effects. The fluorescent probe, DCFH-DA and 5,5′,6,6′-Tetrachloro-1,1′,3,3′-tetraethyl-imidacarbocyanine iodide (JC-1) were applied to detect the reactive oxygen species (ROS) level and mitochondrial membrane potential (ΔΨm). Furthermore, western blots were used to measure the expressions of the apoptosis-related proteins. Under hypoxic conditions, 300 μM and 600 μM of H2S could protect HUVECs against hypoxia-induced injury, as determined by MTT assay. Following the treatment of 60 μM NaHS for 18 h, scratch wound healing assays indicated that the scratch became much narrower than control group. After treatment with 60 μM, 120 μM, and 600 μM NaHS, and hypoxia for 30 min, flow cytometry demonstrated that the ROS concentrations decreased to 95.08% ± 5.52%, 73.14% ± 3.36%, and 73.51% ± 3.05%, respectively, compared with the control group. In addition, the JC-1 assay showed NaHS had a protective effect on mitochondria damage. Additionally, NaHS increased Bcl-2 expression and decreased the expression of Bax, Caspase-3 and Caspase-9 in a dose-dependent way. Our results suggest that H2S can protect endothelial cells and promote migration under hypoxic condition in HUVECs. These effects are partially associated with the preservation of mitochondrial function mediated by regulating the mitochondrial-dependent apoptotic pathway. PMID:23799362

Nicotine protects against DSS colitis through regulating microRNA-124 and STAT3.

PubMed

Qin, Zhen; Wan, Jing-Jing; Sun, Yang; Wu, Tingyu; Wang, Peng-Yuan; Du, Peng; Su, Ding-Feng; Yang, Yili; Liu, Xia

2017-02-01

Although it is generally believed that nicotine accounts for the beneficial effect of smoking on ulcerative colitis, the underlying mechanisms remain not well understood. Our previous finding that nicotine inhibits inflammatory responses through inducing miR-124 prompted us to ask whether the miRNA is involved in the protective action of nicotine against UC. Our present study found that miR-124 expression is upregulated in colon tissues from UC patients and DSS colitis mice. Nicotine treatment further augmented miR-124 expression in lymphocytes isolated from human ulcerative colonic mucosa and ulcerative colon tissues from DSS mice, both in infiltrated lymphocytes and epithelial cells. Moreover, knockdown of miR-124 significantly diminished the beneficial effect of nicotine on murine colitis and IL-6-treated Caco-2 colon epithelial cells. Further analysis indicated that nicotine inhibited STAT3 activation in vivo and in IL-6 treated Caco-2 cells and Jurkat human T lymphocytes, in which miR-124 knockdown led to increased activation of STAT3. Blocking STAT3 activity alone is beneficial for DSS colitis and also abolished nicotine's protective effect in this model. These data indicate that nicotine exerts its protective action in UC through inducing miR-124 and inhibiting STAT3, and suggest that the miR-124/STAT3 system is a potential target for the therapeutic intervention of UC. Nicotine upregulates miR-124 expression in ulcerative colon tissues and cells. MiR-124 is required for the protective role of nicotine in DSS colitis mice and epithelial cells. The protective effect of nicotine in murine DSS colitis depends on blocking STAT3 activation. MiR-124 mediates the inhibitory role of nicotine on STAT3/p-STAT3. Targeting miR-124 and STAT3 represents a novel approach for treating ulcerative colitis.

Mucosal priming of newborn mice with S. Typhi Ty21a expressing anthrax protective antigen (PA) followed by parenteral PA-boost induces B and T cell-mediated immunity that protects against infection bypassing maternal antibodies

PubMed Central

Ramirez, Karina; Ditamo, Yanina; Galen, James E.; Baillie, Les W. J.; Pasetti, Marcela F.

2010-01-01

The currently licensed anthrax vaccine has several limitations and its efficacy has been proven only in adults. Effective immunization of newborns and infants requires adequate stimulation of their immune system, which is competent but not fully activated. We explored the use of the licensed live attenuated S. Typhi vaccine strain Ty21a expressing Bacillus anthracis protective antigen [Ty21a(PA)] followed PA-alum as a strategy for immunizing the pediatric population. Newborn mice primed with a single dose of Ty21a(PA) exhibited high frequencies of mucosal IgA-secreting B cells and IFN-γ-secreting T cells during the neonatal period, none of which was detected in newborns immunized with a single dose of PA-alum. Priming with Ty21a(PA) followed by PA-boost resulted in high levels of PA-specific IgG, toxin-neutralizing and opsonophagocytic antibodies and increased frequency of bone marrow IgG plasma cells and memory B cells compared with repeated immunization with PA-alum alone. Robust B and T cell responses developed even in the presence of maternal antibodies. The prime-boost protected against systemic and respiratory infection. Mucosal priming with a safe and effective S. Typhi-based anthrax vaccine followed by PA-boost could serve as a practical and effective prophylactic approach to prevent anthrax early in life. PMID:20619377

5-HT2A serotonin receptor agonist DOI alleviates cytotoxicity in neuroblastoma cells: role of the ERK pathway.

PubMed

Marinova, Zoya; Walitza, Susanne; Grünblatt, Edna

2013-07-01

Disturbances of serotonergic signaling, including the serotonin 2A (5-HT2A) receptor, have been implicated in neuropsychiatric and neurodegenerative disorders. The aim of the present study was to characterize the effect of a 5-HT2A receptor agonist on cytotoxicity in a neuronal cell line and address the involved mechanism. HTR2A mRNA and protein expression in human neuroblastoma SK-N-SH cells was confirmed. Cells were subjected to serum deprivation and cell viability was monitored continuously with xCELLigence. In a dose-response study the 5-HT2A agonist (±)-2,5-dimethoxy-4-iodoamphetamine hydrochloride (DOI) (25 nM to 5 μM) protected against serum deprivation cytotoxicity. The selective 5-HT2A receptor antagonist MDL 11,939, the general protein tyrosine kinase inhibitor genistein, and the extracellular signal-regulated kinase (ERK) pathway MEK inhibitor U0126, all attenuated DOI's protective effect. An antibody array suggested that 1 μM DOI affected phosphorylation of several tyrosine kinases. Western blot further confirmed that DOI transiently increased ERK phosphorylation, indicating its activation. Finally, protective concentrations of DOI increased cellular mitochondrial mass, an effect prevented by pretreatment with U0126. In conclusion, our results suggest that DOI protects SK-N-SH cells against serum deprivation through ERK pathway activation. They imply 5-HT2A receptor modulation as a potential target for neuroprotection. Copyright © 2013 Elsevier Inc. All rights reserved.

Enhanced Immune Response and Protective Effects of Nano-chitosan-based DNA Vaccine Encoding T Cell Epitopes of Esat-6 and FL against Mycobacterium Tuberculosis Infection

PubMed Central

Feng, Ganzhu; Jiang, Qingtao; Xia, Mei; Lu, Yanlai; Qiu, Wen; Zhao, Dan; Lu, Liwei; Peng, Guangyong; Wang, Yingwei

2013-01-01

Development of a novel and effective vaccine against Mycobacterium tuberculosis (M.tb) is a challenging for preventing TB infection. In this study, a novel nanoparticle-based recombinant DNA vaccine was developed, which contains Esat-6 three T cell epitopes (Esat-6/3e) and fms-like tyrosine kinase 3 ligand (FL) genes (termed Esat-6/3e-FL), and was enveloped with chitosan (CS) nanoparticles (nano-chitosan). The immunologic and protective efficacy of the nano-chitosan-based DNA vaccine (termed nano-Esat-6/3e-FL) was assessed in C57BL/6 mice after intramuscular prime vaccination with the plasmids DNA and nasal boost with the Esat-6/3e peptides. The results showed that the immunized mice remarkably elicited enhanced T cell responses and protection against M.tb H37Rv challenge. These findings indicate that the nano-chitosan can significantly elevate the immunologic and protective effects of the DNA vaccine, and the nano-Esat-6/3e-FL is a useful vaccine for preventing M.tb infection in mice. PMID:23637790

T cells play an essential role in anti-F1 mediated rapid protection against bubonic plague.

PubMed

Levy, Yinon; Flashner, Yehuda; Tidhar, Avital; Zauberman, Ayelet; Aftalion, Moshe; Lazar, Shirley; Gur, David; Shafferman, Avigdor; Mamroud, Emanuelle

2011-09-16

Plague, which is initiated by Yersinia pestis infection, is a fatal disease that progresses rapidly and leads to high mortality rates if not treated. Antibiotics are an effective plague therapy, but antibiotic-resistant Y. pestis strains have been reported and therefore alternative countermeasures are needed. In the present study, we assessed the potential of an F1 plus LcrV-based vaccine to provide protection shortly pre- or post-exposure to a lethal Y. pestis infection. Mice vaccinated up to one day before or even several hours after subcutaneous challenge were effectively protected. Mice immunized one or three days pre-challenge were protected even though their anti-F1 and anti-LcrV titers were below detection levels at the day of challenge. Moreover, using B-cell deficient μMT mice, we found that rapidly induced protective immunity requires the integrity of the humoral immune system. Analysis of the individual contributions of vaccine components to protection revealed that rF1 is responsible for the observed rapid antibody-mediated immunity. Applying anti-F1 passive therapy in the mouse model of bubonic plague demonstrated that anti-F1 F(ab')(2) can delay mortality, but it cannot provide long-lasting protection, as do intact anti-F1 molecules. Fc-dependent immune components, such as the complement system and (to a lesser extent) neutrophils, were found to contribute to mouse survival. Interestingly, T cells but not B cells were found to be essential for the recovery of infected animals following passive anti-F1 mediated therapy. These data extend our understanding of the immune mechanisms required for the development of a rapid and effective post-exposure therapy against plague. Copyright © 2011 Elsevier Ltd. All rights reserved.

Angiogenin in Parkinson Disease Models: Role of Akt Phosphorylation and Evaluation of AAV-Mediated Angiogenin Expression in MPTP Treated Mice

PubMed Central

Steidinger, Trent U.; Slone, Sunny R.; Ding, Huiping; Standaert, David G.; Yacoubian, Talene A.

2013-01-01

The angiogenic factor, angiogenin, has been recently linked to both Amyotrophic Lateral Sclerosis (ALS) and Parkinson Disease (PD). We have recently shown that endogenous angiogenin levels are dramatically reduced in an alpha-synuclein mouse model of PD and that exogenous angiogenin protects against cell loss in neurotoxin-based cellular models of PD. Here, we extend our studies to examine whether activation of the prosurvival Akt pathway is required for angiogenin's neuroprotective effects against 1-methyl-4-phenylpyridinium (MPP+), as observed in ALS models, and to test the effect of virally-mediated overexpression of angiogenin in an in vivo PD model. Using a dominant negative Akt construct, we demonstrate that inhibition of the Akt pathway does not reduce the protective effect of angiogenin against MPP+ toxicity in the dopaminergic SH-SY5Y cell line. Furthermore, an ALS-associated mutant of angiogenin, K40I, which fails to induce Akt phosphorylation, was similar to wildtype angiogenin in protection against MPP+. These results confirm previous work showing neuroprotective effects of angiogenin against MPP+, and indicate that Akt is not required for this protective effect. We also investigated whether adeno-associated viral serotype 2 (AAV2)-mediated overexpression of angiogenin protects against dopaminergic neuron loss in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model. We found that angiogenin overexpression using this approach does not reduce the MPTP-induced degeneration of dopaminergic cells in the substantia nigra, nor limit the depletion of dopamine and its metabolites in the striatum. Together, these findings extend the evidence for protective effects of angiogenin in vitro, but also suggest that further study of in vivo models is required to translate these effects into meaningful therapies. PMID:23409128

Prostaglandin E2 blocks menadione-induced apoptosis through the Ras/Raf/Erk signaling pathway in promonocytic leukemia cell lines.

PubMed

Yeo, Hyun-Seok; Shehzad, Adeeb; Lee, Young Sup

2012-04-01

Altered oxidative stress has long been observed in cancer cells, and this biochemical property of cancer cells represents a specific vulnerability that can be exploited for therapeutic benefit. The major role of an elevated oxidative stress for the efficacy of molecular targeted drugs is under investigation. Menadione is considered an attractive model for the study of oxidative stress, which can induce apoptosis in human leukemia HL-60 cell lines. Prostaglandin E(2) (PGE(2)) via its receptors not only promotes cell survival but also reverses apoptosis and promotes cancer progression. Here, we present evidence for the biological role of PGE(2) as a protective agent of oxidative stress-induced apoptosis in monocytic cells. Pretreatment of HL-60 cells with PGE(2) markedly ameliorated the menadione-induced apoptosis and inhibited the degradation of PARP and lamin B. The EP(2) receptor antagonist AH6809 abrogated the inhibitory effect of PGE(2), suggesting the role of the EP(2)/cAMP system. The PKA inhibitor H89 also reversed apoptosis and decreased the PKA activity that was elevated 10-fold by PGE(2). The treatment of HL-60 cells with NAC or zinc chloride showed a similar protective effect as with PGE(2) on menadione-treated cells. Furthermore, PGE(2) activated the Ras/Raf/MEK pathway, which in turn initiated ERK activation, and ultimately protected menadione-induced apoptosis. These results imply that PGE(2) via cell survival pathways may protect oxidative stress-induced apoptosis in monocytic cells. This study warrants further pre-clinical investigation as well as application towards leukemia clinics.

Protective effect of aged garlic extract (AGE) on the apoptosis of intestinal epithelial cells caused by methotrexate.

PubMed

Li, Tiesong; Ito, Kousei; Sumi, Shin-Ichiro; Fuwa, Toru; Horie, Toshiharu

2009-04-01

Methotrexate (MTX) causes intestinal damage, resulting in diarrhea. The side effects often disturb the cancer chemotherapy. We previously reported that AGE protected the small intestine of rats from the MTX-induced damage. In the present paper, the mechanism of the protection of AGE against the MTX-induced damage of small intestine was investigated, using IEC-6 cells originating from rat jejunum crypt. The viability and apoptosis of IEC-6 cells were examined in the presence of MTX and/or AGE. The viability of IEC-6 cells exposed to MTX was decreased by the increase of MTX concentration. The MTX-induced loss of viable IEC-6 cells was almost completely prevented by the presence of more than 0.1% AGE. In IEC-6 cells exposed to MTX, the cromatin condensation, DNA fragmentation, caspase-3 activation and cytochrome c release were observed. These were preserved to the control levels by the presence of AGE. MTX markedly decreased intracellular GSH in IEC-6 cells, but the presence of AGE in IEC-6 cells with MTX preserved intracellular GSH to the control level. IEC-6 cells in G2/M stage markedly decreased 72 h after the MTX treatment, which was preserved to the control level by the presence of AGE. These results indicated that AGE protected IEC-6 cells from the MTX-induced damage. The MTX-induced apoptosis of IEC-6 cells was shown to be depressed by AGE. AGE may be useful for the cancer chemotherapy with MTX, since AGE reduces the MTX-induced intestinal damage.

Protection of adult rat cardiac myocytes from ischemic cell death: role of caveolar microdomains and delta-opioid receptors.

PubMed

Patel, Hemal H; Head, Brian P; Petersen, Heidi N; Niesman, Ingrid R; Huang, Diane; Gross, Garrett J; Insel, Paul A; Roth, David M

2006-07-01

The role of caveolae, membrane microenvironments enriched in signaling molecules, in myocardial ischemia is poorly defined. In the current study, we used cardiac myocytes prepared from adult rats to test the hypothesis that opioid receptors (OR), which are capable of producing cardiac protection in vivo, promote cardiac protection in cardiac myocytes in a caveolae-dependent manner. We determined protein expression and localization of delta-OR (DOR) using coimmunohistochemistry, caveolar fractionation, and immunoprecipitations. DOR colocalized in fractions with caveolin-3 (Cav-3), a structural component of caveolae in muscle cells, and could be immunoprecipitated by a Cav-3 antibody. Immunohistochemistry confirmed plasma membrane colocalization of DOR with Cav-3. Cardiac myocytes were subjected to simulated ischemia (2 h) or an ischemic preconditioning (IPC) protocol (10 min ischemia, 30 min recovery, 2 h ischemia) in the presence and absence of methyl-beta-cyclodextrin (MbetaCD, 2 mM), which binds cholesterol and disrupts caveolae. We also assessed the cardiac protective effects of SNC-121 (SNC), a selective DOR agonist, on cardiac myocytes with or without MbetaCD and MbetaCD preloaded with cholesterol. Ischemia, simulated by mineral oil layering to inhibit gas exchange, promoted cardiac myocyte cell death (trypan blue staining), a response blunted by SNC (37 +/- 3 vs. 59 +/- 3% dead cells in the presence and absence of 1 muM SNC, respectively, P < 0.01) or by use of the IPC protocol (35 +/- 4 vs. 62 +/- 3% dead cells, P < 0.01). MbetaCD treatment, which disrupted caveolae (as detected by electron microscopy), fully attenuated the protective effects of IPC or SNC, resulting in cell death comparable to that of the ischemic group. By contrast, SNC-induced protection was not abrogated in cells incubated with cholesterol-saturated MbetaCD, which maintained caveolae structure and function. These findings suggest a key role for caveolae, perhaps through enrichment of signaling molecules, in contributing to protection of cardiac myocytes from ischemic damage.

Delta-Tocotrienol: Radiation Protection and Effects on Signal Transduction Pathways

DTIC Science & Technology

2011-06-15

Delta- Tocotrienol : Radiation Protection and Effects on Signal Transduction Pathways Venkataraman Srinivasan, PhD Mang Xiao, MD Principal...2011 2. REPORT TYPE 3. DATES COVERED 00-00-2011 to 00-00-2011 4. TITLE AND SUBTITLE Delta- Tocotrienol : Radiation Protection And Effects On...Mechanisms? 17 Survival of γ-irradiated mouse bone marrow and primary human hematopoietic CD34+ cells was significantly enhanced by Delta- tocotrienol (DT3

Nonsense-Mediated Decay in Genetic Disease: Friend or Foe?

PubMed Central

Miller, Jake N.; Pearce, David A.

2014-01-01

Eukaryotic cells utilize various RNA quality control mechanisms to ensure high fidelity of gene expression, thus protecting against the accumulation of nonfunctional RNA and the subsequent production of abnormal peptides. Messenger RNAs (mRNAs) are largely responsible for protein production, and mRNA quality control is particularly important for protecting the cell against the downstream effects of genetic mutations. Nonsense-mediated decay (NMD) is an evolutionarily conserved mRNA quality control system in all eukaryotes that degrades transcripts containing premature termination codons (PTCs). By degrading these aberrant transcripts, NMD acts to prevent the production of truncated proteins that could otherwise harm the cell through various insults, such as dominant negative effects or the ER stress response. Although NMD functions to protect the cell against the deleterious effects of aberrant mRNA, there is a growing body of evidence that mutation-, codon-, gene-, cell-, and tissue-specific differences in NMD efficiency can alter the underlying pathology of genetic disease. In addition, the protective role that NMD plays in genetic disease can undermine current therapeutic strategies aimed at increasing the production of full-length functional protein from genes harboring nonsense mutations. Here, we review the normal function of this RNA surveillance pathway and how it is regulated, provide current evidence for the role that it plays in modulating genetic disease phenotypes, and how NMD can be used as a therapeutic target. PMID:25485595

Berberine exerts antioxidant effects via protection of spiral ganglion cells against cytomegalovirus-induced apoptosis.

PubMed

Zhuang, Wei; Li, Ting; Wang, Caiji; Shi, Xi; Li, Yalan; Zhang, Shili; Zhao, Zeqi; Dong, Hongyan; Qiao, Yuehua

2018-06-01

Cytomegalovirus (CMV) is the leading cause of sensorineural hearing loss (SNHL) in children because of its damage to the cochlea and spiral ganglion cells. Therefore, it has become a top priority to devise new methods to effectively protect spiral ganglion cells from damage. Berberine (BBR) has gained attention for its vast beneficial biological effects through immunomodulation, and its anti-inflammatory and anti-apoptosis properties. However, the effect of BBR on spiral ganglion cells and molecular mechanisms are still unclear. This study aims to investigate whether BBR has an anti-apoptosis effect in CMV-induced apoptosis in cultured spiral ganglion cells and explore the possible mechanism. In this study, TUNEL and MTT assays significantly demonstrated that low doses of BBR did not promote cell apoptosis and they also inhibited the CMV-induced cultured spiral ganglion cell apoptosis. Immunofluorescence and Western blot assays indicated that the anti-apoptosis effect of BBR was related to Nox3. Mitochondrial calcium and Western blot assays revealed that NMDAR1 mediated this anti-apoptosis effect. Our results demonstrated that BBR exerted an anti-apoptosis effect against CMV in cultured spiral ganglion cells, and the mechanism is related to NMDAR1/Nox3-mediated mitochondrial reactive oxygen species (ROS) generation. Copyright © 2018 Elsevier Inc. All rights reserved.

Procyanidins protect Fao cells against hydrogen peroxide-induced oxidative stress.

PubMed

Roig, Roser; Cascón, Esther; Arola, Lluis; Bladé, Cinta; Salvadó, M Josepa

2002-08-15

In this paper, we evaluate the extent to which flavonoids in red wine (catechin, epicatechin, quercetin and procyanidins) protect against hydrogen peroxide-induced oxidative stress in Fao cells. When cells were exposed to H(2)O(2), malondialdehyde (MDA) levels, oxidized glutathione (GSSG) levels and lactate dehydrogenase (LDH) release increased, indicating membrane damage and oxidative stress. All the flavonoids studied, and in particular epicatechin and quercetin, protected the plasma membrane. Only procyanidins lowered MDA levels and LDH leakage, maintained a higher reduced/oxidized glutathione ratio, and increased catalase/superoxide dismutase and glutathione peroxidase/superoxide dismutase ratios, and glutathione reductase and glutathione transferase activities. These results show that the procyanidin mixture has a greater antioxidant effect than the individual flavonoids studied, probably due to its oligomer content and/or the additive/synergistic effect of its compounds. This suggests that the mixture of flavonoids found in wine has a greater effect than individual phenols, which may explain many of the healthy effects attributed to wine.

Allicin protects against cisplatin-induced vestibular dysfunction by inhibiting the apoptotic pathway.

PubMed

Wu, Xianmin; Cai, Jing; Li, Xiaofei; Li, He; Li, Jianfeng; Bai, Xiaohui; Liu, Wenwen; Han, Yuechen; Xu, Lei; Zhang, Daogong; Wang, Haibo; Fan, Zhaomin

2017-06-15

Cisplatin is an anticancer drug that causes the impairment of inner ear function as side effects, including hearing loss and balance dysfunction. The purpose of this study was to investigate the effects of allicin against cisplatin-induced vestibular dysfunction in mice and to make clear the mechanism underlying the protective effects of allicin on oto-vestibulotoxicity. Mice intraperitoneally injected with cisplatin exhibited vestibular dysfunction in swimming test, which agreed with impairment in vestibule. However, these impairments were significantly prevented by pre-treatment with allicin. Allicin markedly reduced cisplatin-activated expression of cleaved-caspase-3 in hair cells and vascular layer cells of utricule, saccule and ampulla, but also decreased AIF nuclear translocation of hair cells in utricule, saccule and ampulla. These results showed that allicin played an effective role in protecting vestibular dysfunction induced by cisplatin via inhibiting caspase-dependent and caspase-independent apoptotic pathways. Therefore, allicin may be useful in preventing oto-vestibulotoxicity mediated by cisplatin. Copyright © 2017. Published by Elsevier B.V.

Histaminergic regulation of NK-cells: protection against monocyte-induced apoptosis.

PubMed

Hansson, M; Asea, A; Hermodsson, S; Hellstrand, K

1996-08-01

Human natural killer (NK) cells (with CD3-/56+ phenotype) acquired features characteristic of apoptosis after incubation with autologous monocytes, as revealed by apoptotic nuclear morphology and degradation of DNA into oligonucleosomal fragments. The monocyte-induced apoptosis in NK-cells was prevented by the biogenic amine histamine at concentrations exceeding 0.1 microM. The protective effect of histamine was blocked by the H2-receptor (H2R) antagonist ranitidine but not by AH202399 A, a chemical control to ranitidine devoid of H2R affinity. It is concluded that histaminergic mechanisms may serve to protect NK cells from damage inflicted by products of the oxidative metabolism of monocytes.

Genetic vaccines to potentiate the effective CD103+ dendritic cell-mediated cross-priming of antitumor immunity.

PubMed

Zhang, Yi; Chen, Guo; Liu, Zuqiang; Tian, Shenghe; Zhang, Jiying; Carey, Cara D; Murphy, Kenneth M; Storkus, Walter J; Falo, Louis D; You, Zhaoyang

2015-06-15

The development of effective cancer vaccines remains an urgent, but as yet unmet, clinical need. This deficiency is in part due to an incomplete understanding of how to best invoke dendritic cells (DC) that are crucial for the induction of tumor-specific CD8(+) T cells capable of mediating durable protective immunity. In this regard, elevated expression of the transcription factor X box-binding protein 1 (XBP1) in DC appears to play a decisive role in promoting the ability of DC to cross-present Ags to CD8(+) T cells in the therapeutic setting. Delivery of DNA vaccines encoding XBP1 and tumor Ag to skin DC resulted in increased IFN-α production by plasmacytoid DC (pDC) from skin/tumor draining lymph nodes and the cross-priming of Ag-specific CD8(+) T cell responses associated with therapeutic benefit. Antitumor protection was dependent on cross-presenting Batf3(+) DC, pDC, and CD8(+) T cells. CD103(+) DC from the skin/tumor draining lymph nodes of the immunized mice appeared responsible for activation of Ag-specific naive CD8(+) T cells, but were dependent on pDC for optimal effectiveness. Similarly, human XBP1 improved the capacity of human blood- and skin-derived DC to activate human T cells. These data support an important intrinsic role for XBP1 in DC for effective cross-priming and orchestration of Batf3(+) DC-pDC interactions, thereby enabling effective vaccine induction of protective antitumor immunity. Copyright © 2015 by The American Association of Immunologists, Inc.

Protective effect of polysaccharides from Sargassum horneri against oxidative stress in RAW264.7 cells.

PubMed

Wen, Zheng-Shun; Liu, Li-Jia; OuYang, Xiao-Kun; Qu, You-Le; Chen, Yin; Ding, Guo-Fang

2014-07-01

This study was designed to investigate chemical composition and the protective effects of polysaccharides isolated from Sargassum horneri against hydrogen peroxide (H2O2)-induced oxidative injury in RAW264.7 cells. Results showed that isolated polysaccharides (SHSc) and the major fractions (SHS1, SHS0.5) contained sulfate ester, and SHS1 was high fucose-containing sulfated polysaccharide. After preincubation with three isolated polysaccharides, RAW264.7 cells viability were significantly restored and decreased in cellular LDH release (P<0.05). SHS1 and SHS0.5 decreased intracellular ROS level, intracellular NO and malonic dialdehyde (MDA) level (P<0.05), restoring activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) (P<0.05), decreasing inducible nitric oxide synthase (iNOS) (P<0.05). Moreover, preincubation of SHS1 with RAW264.7 cells resulted in the increase of the gene expression level of endogenous antioxidant enzymes such as MnSOD and GSH-Px (P<0.05). These results clearly showed that SHSc and its fractions could attenuate H2O2-induced stress injury in RAW264.7 cells, and a similar efficiency in protecting RAW264.7 cells against H2O2-induced oxidative injury between SHS1 and Vitamin C. Taken together, our findings suggested that SHS1 can effectively protect RAW264.7 cells against oxidative stress by H2O2, which might be used as a potential natural antioxidant in the functional food and pharmaceutical industries. Copyright © 2014 Elsevier B.V. All rights reserved.

Protective effects of peroxisome proliferator-activated receptor agonists on human podocytes: proposed mechanisms of action

PubMed Central

Miglio, Gianluca; Rosa, Arianna Carolina; Rattazzi, Lorenza; Grange, Cristina; Camussi, Giovanni; Fantozzi, Roberto

2012-01-01

BACKGROUND AND PURPOSE Peroxisome proliferator-activated receptor (PPAR) agonists exert anti-albuminuric effects. However, the nephroprotective effects of these drugs remain to be fully understood. We have investigated whether gemfibrozil, GW0742 and pioglitazone protect human podocytes against nutrient deprivation (ND)-induced cell death and the role of mitochondrial biogenesis as a cytoprotective process. EXPERIMENTAL APPROACH Immortalized human podocytes were pre-treated with the PPAR agonists and exposed to ND (5 h) under normoxia, hypoxia or in the presence of pyruvate. Cell death was measured at the end of the ND and of the recovery phase (24 h). Mitochondrial mass, cytochrome c oxidase (COX) subunits 1 and 4 were measured as markers of mitochondrial cell content, while membrane potential as an index of mitochondrial function. PGC-1α, NRF1 and Tfam expression was studied, as crucial regulators of mitochondrial biogenesis. KEY RESULTS Cell pre-treatment with gemfibrozil, GW0742, or pioglitazone significantly decreased the ND-induced cell loss, necrosis and apoptosis. These effects were attenuated by hypoxia and potentiated by pyruvate. Pre-treatment with these drugs significantly increased mitochondrial cell content, while it did not affect mitochondrial function. In all these experiments pioglitazone exerted significantly larger effects than gemfibrozil or GW0742. CONCLUSIONS AND IMPLICATIONS Gemfibrozil, GW0742 and pioglitazone may exert direct protective effects on human podocytes. Mitochondrial biogenesis is a cell response to the PPAR agonists related to their cytoprotective activity. These results provide a mechanistic support to the clinical evidence indicating PPAR agonists as disease-modifying agents for glomerular diseases. PMID:22594945

IGF-1 and TGF-β stimulate cystine/glutamate exchange activity in dental pulp cells

PubMed Central

Pauly, Katherine; Fritz, Kimberly; Furey, Alyssa; Lobner, Doug

2011-01-01

Introduction The growth factors IGF-1 and TGF-β are protective to dental pulp cells in culture against the toxicity of the composite materials Durafill VS and Flow Line. Since the toxicity of these materials is mediated by oxidative stress, it seemed possible that the protective effects of IGF-1 and TGF-β were through enhancement of an endogenous antioxidant mechanism. Methods We used cultured dental pulp cells to determine the mechanism of the protective effects of IGF-1 and TGF-β, focusing on the glutathione system and the role of cystine/glutamate exchange (system xc-). Results We found that the toxicity of Durafill VS and Flow Line was attenuated by addition of glutathione monoethylester, suggesting a specific role for the cellular antioxidant glutathione. Supporting this hypothesis we found that IGF-1 and TGF-β were protective against the toxicity of the glutathione synthesis inhibitor buthionine sulfoximine. Since levels of cellular cystine are the limiting factor in the production of glutathione we tested the effects of IGF-1 and TGF-β on cystine uptake. Both growth factors stimulated system xc- mediated cystine uptake. Furthermore, they attenuated the glutathione depletion induced by Durafill VS and Flow Line. Conclusions The results suggest that IGF-1 and TGF-β are protective through the stimulation of system xc- mediated cystine uptake leading to maintenance of cellular glutathione. This novel action of growth factors on dental pulp cells has implications not only for preventing toxicity of dental materials but also for the general function of these cells. PMID:21689549

Lactoferrin for prevention of common viral infections.

PubMed

Wakabayashi, Hiroyuki; Oda, Hirotsugu; Yamauchi, Koji; Abe, Fumiaki

2014-11-01

Although lactoferrin has many biological functions, the host-protective effects against pathogenic microorganisms including bacteria, fungi, and viruses are regarded as one of the most important. Here, we review research on the protective role of lactoferrin administration against common viral infections. Many studies have shown the in vitro antiviral activity of lactoferrin against viral pathogens that cause common infections such as the common cold, influenza, gastroenteritis, summer cold, and herpes, where lactoferrin inhibits mainly viral attachment to the target cells. Recently, studies indicating the in vivo protective effects of lactoferrin by oral administration against common viral infections have been increasing. For instance, norovirus is an extremely important emerging human pathogen that causes a majority of gastroenteritis outbreaks worldwide that may be a target candidate for lactoferrin. Lactoferrin consumption reduced the incidence of noroviral gastroenteritis in children and a similar effect was observed in a wide range of ages in a preliminary survey. A recent in vitro study reported that lactoferrin inhibits both cellular attachment of the murine norovirus, a virus closely-related to the human norovirus, and viral replication in the cells by inducing antiviral cytokines interferon (IFN)-α/β. Lactoferrin administration also enhances NK cell activity and Th1 cytokine responses, which lead to protection against viral infections. In conclusion, lactoferrin consumption may protect the host from viral infections through inhibiting the attachment of a virus to the cells, replication of the virus in the cells, and enhancement of systemic immune functions. Copyright © 2014 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

R-spondin3-LGR4 signaling protects hepatocytes against DMOG-induced hypoxia/reoxygenation injury through activating β-catenin.

PubMed

Liu, Shiying; Yin, Yue; Yu, Ruili; Li, Yin; Zhang, Weizhen

2018-04-30

Leucine-rich repeat G-protein-coupled receptor 4 (LGR4) and its ligands R-spondin1-4 (Rspos) have been vastly investigated in embryonic development. The biological functions of Rspos-LGR4 system in liver remains largely unknown. Here, we explored whether it protects hepatocytes against hypoxia/reoxygenation (H/R) induced damage. H/R injury was induced by dimethyloxalylglycine (DMOG) in AML12 cells and the effects of Rspo3 on cell proliferation and apoptosis were assessed. Specific shRNAs were used to interfere LGR4 or β-catenin. DMOG caused hepatocytes damage evidenced by increase in HIF-1α, cell death and apoptosis genes p27 and Bax, with concurrent decrease of cell proliferation genes PCNA and CyclinD1. Of all the Rspos, Rspo3 is predominantly expressed in AML12 hepatocytes. Importantly, Rspo3 demonstrated an alteration in a manner similar to proliferation-related genes during H/R injury. Rspo3 pretreatment rendered hepatocytes less vulnerable to DMOG induced H/R injury. Ablation of LGR4 using shRNA attenuated the protective effects of Rspo3. Wnt3a also protected AML12 cells from damages caused by H/R, showing enhanced proliferation activity. Notably, knockdown of β-catenin in hepatocytes completely abolished the effect of Rspo3 pretreatment on the expression levels of PCNA and CyclinD1. Rspo3-LGR4 axis protects hepatocytes from H/R injury via activating β-catenin. Copyright © 2018. Published by Elsevier Inc.

Negundoside, an iridiod glycoside from leaves of Vitex negundo, protects human liver cells against calcium-mediated toxicity induced by carbon tetrachloride

PubMed Central

Tasduq, Sheikh A; Kaiser, Peerzada J; Gupta, Bishan D; Gupta, Vijay K; Johri, Rakesh K

2008-01-01

AIM: To evaluate the protective effect of 2'-p-hydroxybenzoylmussaenosidic acid [negundoside (NG), against carbon tetrachloride (CCl4)-induced toxicity in HuH-7 cells. METHODS: CCl4 is a well characterized hepatotoxin, and inducer of cytochrome P450 2E1 (CYP2E1)-mediated oxidative stress. In addition, lipid peroxidation and accumulation of intracellular calcium are important steps in the pathway involved in CCl4 toxicity. Liver cells (HuH-7) were treated with CCl4, and the mechanism of the cytoprotective effect of NG was assessed. Silymarin, a known hepatoprotective drug, was used as control. RESULTS: NG protected HuH-7 cells against CCl4 toxicity and loss of viability without modulating CYP2E1 activity. Prevention of CCl4 toxicity was associated with a reduction in oxidative damage as reflected by decreased generation of reactive oxygen species (ROS), a decrease in lipid peroxidation and accumulation of intracellular Ca2+ levels and maintenance of intracellular glutathione homeostasis. Decreased mitochondrial membrane potential (MMP), induction of caspases mediated DNA fragmentation and cell cycle arrest, as a result of CCl4 treatment, were also blocked by NG. The protection afforded by NG seemed to be mediated by activation of cyclic adenosine monophosphate (cAMP) synthesis and inhibition of phospholipases (cPLA2). CONCLUSION: NG exerts a protective effect on CYP2E1-dependent CCl4 toxicity via inhibition of lipid peroxidation, followed by an improved intracellular calcium homeostasis and inhibition of Ca2+-dependent proteases. PMID:18595136

Agmatine protects retinal ganglion cells from hypoxia-induced apoptosis in transformed rat retinal ganglion cell line

PubMed Central

Hong, Samin; Lee, Jong Eun; Kim, Chan Yun; Seong, Gong Je

2007-01-01

Background Agmatine is an endogenous polyamine formed by the decarboxylation of L-arginine. We investigated the protective effects of agmatine against hypoxia-induced apoptosis of immortalized rat retinal ganglion cells (RGC-5). RGC-5 cells were cultured in a closed hypoxic chamber (5% O2) with or without agmatine. Cell viability was determined by lactate dehydrogenase (LDH) assay and apoptosis was examined by annexin V and caspase-3 assays. Expression and phosphorylation of mitogen-activated protein kinases (MAPKs; JNK, ERK p44/42, and p38) and nuclear factor-kappa B (NF-κB) were investigated by Western immunoblot analysis. The effects of agmatine were compared to those of brain-derived neurotrophic factor (BDNF), a well-known protective neurotrophin for retinal ganglion cells. Results After 48 hours of hypoxic culture, the LDH assay showed 52.3% cell loss, which was reduced to 25.6% and 30.1% when agmatine and BDNF were administered, respectively. This observed cell loss was due to apoptotic cell death, as established by annexin V and caspase-3 assays. Although total expression of MAPKs and NF-κB was not influenced by hypoxic injury, phosphorylation of these two proteins was increased. Agmatine reduced phosphorylation of JNK and NF-κB, while BDNF suppressed phosphorylation of ERK and p38. Conclusion Our results show that agmatine has neuroprotective effects against hypoxia-induced retinal ganglion cell damage in RGC-5 cells and that its effects may act through the JNK and NF-κB signaling pathways. Our data suggest that agmatine may lead to a novel therapeutic strategy to reduce retinal ganglion cell injury related to hypoxia. PMID:17908330

Isogentisin--a novel compound for the prevention of smoking-caused endothelial injury.

PubMed

Schmieder, Astrid; Schwaiger, Stefan; Csordas, Adam; Backovic, Aleksandar; Messner, Barbara; Wick, Georg; Stuppner, Hermann; Bernhard, David

2007-10-01

The best strategy in the fight against tobacco-induced diseases is prevention. However, more than one billion people around the world are smokers. Most of these people will develop or already suffer from tobacco-induced diseases. In this project, we screened 22 natural alpine plant extracts for their potential to protect human vascular endothelial cells from cigarette smoke-induced cell damage. Extracts from Gentiana lutea (Yellow Gentian) proved to be effective, and were therefore subjected to bio-guided fractionation. Although our analyses suggest that G. lutea contains several active principles, fractions containing isogentisin (1,3-dihydroxy-7-methoxyxanthone), and pure isogentisin, were most effective. In experiments addressing the nature of the mechanism of protection, we were able to show that isogentisin does not directly interfere with cigarette smoke chemicals. Addition of isogentisin to the cells as long as 4.5h after exposure to cigarette smoke chemicals protected endothelial cells from cell death. Finally, detailed analyses of intracellular oxidative stress and protein oxidation suggest that isogentisin promotes cell survival by activating cellular repair functions.

Protective effects of red wine flavonols on 4-hydroxynonenal-induced apoptosis in PC12 cells.

PubMed

Jang, Young Jin; Kang, Nam Joo; Lee, Ki Won; Lee, Hyong Joo

2009-08-01

There is accumulating evidence that a moderate consumption of red wine has health benefits, such as the inhibition of neurodegenerative diseases. Although this is generally attributed to resveratrol, the protective mechanisms and the active substance(s) remain unclear. We examined whether and how red wine extract (RWE) and red wine flavonols quercetin and myricetin inhibited 4-hydroxynonenal (HNE)-induced apoptosis of rat pheochromocytoma PC12 cells. RWE attenuated HNE-induced PC12 cell death in a dose-dependent manner. HNE induced cleavage of poly(ADP-ribose) polymerase, which is involved in DNA repair in the nucleus, and this was inhibited by RWE treatment. Treatment with RWE also inhibited HNE-induced nuclear condensation in PC12 cells. Data of 2',7'-dichlorofluorescin diacetate showed that RWE protected against apoptosis of PC12 cells by attenuating intracellular reactive oxygen species. The cytoprotective effects on HNE-induced cell death were stronger for quercetin and myricetin than for resveratrol. HNE-induced nuclear condensation was attenuated by quercetin and myricetin. These results suggest that the neuroprotective potential of red wine is attributable to flavonols rather than to resveratrol.

Renal ischemia-reperfusion injury and adenosine 2A receptor-mediated tissue protection: the role of CD4+ T cells and IFN-gamma.

PubMed

Day, Yuan-Ji; Huang, Liping; Ye, Hong; Li, Li; Linden, Joel; Okusa, Mark D

2006-03-01

A(2A) adenosine receptor (A(2A)R)-expressing bone marrow (BM)-derived cells contribute to the renal protective effect of A(2A) agonists in renal ischemia-reperfusion injury (IRI). We performed IRI in mice lacking T and B cells to determine whether A(2A)R expressed in CD4+ cells mediate protection from IRI. Rag-1 knockout (KO) mice were protected in comparison to wild-type (WT) mice when subjected to IRI. ATL146e, a selective A(2A) agonist, did not confer additional protection. IFN-gamma is an important early signal in IRI and is thought to contribute to reperfusion injury. Because IFN-gamma is produced by kidney cells and T cells we performed IRI in BM chimeras in which the BM of WT mice was reconstituted with BM from IFN-gamma KO mice (IFN-gamma KO-->WT chimera). We observed marked reduction in IRI in comparison to WT-->WT chimeras providing additional indirect support for the role of T cells. To confirm the role of CD4+ A(2A)R in mediating protection from IRI, Rag-1 KO mice were subjected to ischemia-reperfusion. The protection observed in Rag-1 KO mice was reversed in Rag-1 KO mice that were adoptively transferred WT CD4+ cells (WT CD4+-->Rag-1 KO) or A(2A) KO CD4+ cells (A(2A) KO CD4+-->Rag-1 KO). ATL146e reduced injury in WT CD4+-->Rag-1 KO mice but not in A(2A) KO CD4+-->Rag-1 KO mice. Rag-1 KO mice reconstituted with CD4+ cells derived from IFN-gamma KO mice (IFN-gamma CD4+-->Rag-1 KO) were protected from IRI; ATL146e conferred no additional protection. These studies demonstrate that CD4+ IFN-gamma contributes to IRI and that A(2A) agonists mediate protection from IRI through action on CD4+ cells.

Memory Th1 Cells Are Protective in Invasive Staphylococcus aureus Infection

PubMed Central

Lalor, Stephen J.; Leech, John M.; O’Keeffe, Kate M.; Mac Aogáin, Micheál; O’Halloran, Dara P.; Lacey, Keenan A.; Tavakol, Mehri; Hearnden, Claire H.; Fitzgerald-Hughes, Deirdre; Humphreys, Hilary; Fennell, Jérôme P.; van Wamel, Willem J.; Foster, Timothy J.; Geoghegan, Joan A.; Lavelle, Ed C.; Rogers, Thomas R.; McLoughlin, Rachel M.

2015-01-01

Mechanisms of protective immunity to Staphylococcus aureus infection in humans remain elusive. While the importance of cellular immunity has been shown in mice, T cell responses in humans have not been characterised. Using a murine model of recurrent S. aureus peritonitis, we demonstrated that prior exposure to S. aureus enhanced IFNγ responses upon subsequent infection, while adoptive transfer of S. aureus antigen-specific Th1 cells was protective in naïve mice. Translating these findings, we found that S. aureus antigen-specific Th1 cells were also significantly expanded during human S. aureus bloodstream infection (BSI). These Th1 cells were CD45RO+, indicative of a memory phenotype. Thus, exposure to S. aureus induces memory Th1 cells in mice and humans, identifying Th1 cells as potential S. aureus vaccine targets. Consequently, we developed a model vaccine comprising staphylococcal clumping factor A, which we demonstrate to be an effective human T cell antigen, combined with the Th1-driving adjuvant CpG. This novel Th1-inducing vaccine conferred significant protection during S. aureus infection in mice. This study notably advances our understanding of S. aureus cellular immunity, and demonstrates for the first time that a correlate of S. aureus protective immunity identified in mice may be relevant in humans. PMID:26539822

Dexamethasone protection from TNF-alpha-induced cell death in MCF-7 cells requires NF-kappaB and is independent from AKT.

PubMed

Machuca, Catalina; Mendoza-Milla, Criselda; Córdova, Emilio; Mejía, Salvador; Covarrubias, Luis; Ventura, José; Zentella, Alejandro

2006-02-21

The biochemical bases for hormone dependence in breast cancer have been recognized as an important element in tumor resistance, proliferation and metastasis. On this respect, dexamethasone (Dex) dependent protection against TNF-alpha-mediated cell death in the MCF-7 cell line has been demonstrated to be a useful model for the study of this type of cancer. Recently, cytoplasmic signaling induced by steroid receptors has been described, such as the activation of the PI3K/Akt and NF-kappaB pathways. We evaluated their possible participation in the Dex-dependent protection against TNF-alpha-mediated cell death. Cellular cultures of the MCF-7 cell line were exposed to either, TNF-alpha or TNF-alpha and Dex, and cell viability was evaluated. Next, negative dominants of PI3K and IkappaB-alpha, designed to block the PI3K/Akt and NF-kappaB pathways, respectively, were transfected and selection and evaluation of several clones overexpressing the mutants were examined. Also, correlation with inhibitor of apoptosis proteins (IAPs) expression was examined. Independent inhibition of these two pathways allowed us to test their participation in Dex-dependent protection against TNF-alpha-cytotoxicity in MCF-7 cells. Expression of the PI3K dominant negative mutant did not alter the protection conferred by Dex against TNF-alpha mediated cell death. Contrariwise, clones expressing the IkappaB-alpha dominant negative mutant lost the Dex-conferred protection against TNF-alpha. In these clones degradation of c-IAP was accelerated, while that of XIAP was remained unaffected. NF-kappaB, but not PI3K/Akt activation, is required for the Dex protective effect against TNF-alpha-mediated cell death, and correlates with lack of degradation of the anti-apoptotic protein c-IAP1.

Major role for CD8 T cells in the protection against Toxoplasma gondii following dendritic cell vaccination.

PubMed

Guiton, R; Zagani, R; Dimier-Poisson, I

2009-10-01

Toxoplasma gondii is the causative agent of toxoplasmosis, a worldwide zoonosis for which an effective vaccine is needed. Vaccination with pulsed dendritic cells is very efficient but their use in a vaccination protocol is unconceivable. Nevertheless, unravelling the induced effector mechanisms is crucial to design new vaccine strategies. We vaccinated CBA/J mice with parasite extract-pulsed dendritic cells, challenged them with T. gondii cysts and carried out in vivo depletion of CD4(+) or CD8(+) T lymphocytes to study the subsequent cellular immune response and protective mechanisms. CD4(+) lymphocytes were poorly implicated either in spleen and mesenteric lymph node (MLN) cytokine secretion or in mice protection. By contrast, the increasing number of intracerebral cysts and depletion of CD8(+) cells were strongly correlated, revealing a prominent role for CD8(+) lymphocytes in the protection of mice. Splenic CD8(+) lymphocytes induce a strong Th1 response controlled by a Th2 response whereas CD8(+) cells from MLNs inhibit both Th1 and Th2 responses. CD8(+) cells are the main effectors following dendritic cell vaccination and Toxoplasma infection while CD4(+) T cells only play a minor role. This contrasts with T. gondii infection which elicits the generation of CD4(+) and CD8(+) T cells that provide protective immunity.

116 kDa glycoprotein isolated from Ulmus davidiana Nakai (UDN) inhibits glucose/glucose oxidase (G/GO)-induced apoptosis in BNL CL.2 cells.

PubMed

Ko, Jeong-Hyeon; Lee, Sei-Jung; Lim, Kye-Taek

2005-09-14

Ulmus davidiana Nakai (UDN) has been used in folk medicine for its anti-inflammatory activity. In the present study, we investigated the antiapoptotic effect of UDN glycoprotein in glucose/glucose oxidase (G/GO)-induced BNL CL.2 cells. To evaluate the antiapoptotic effect of UDN glycoprotein, experiments were carried out using Western blot analysis for nuclear factor-kappa B (NF-kappaB), caspase-3, and poly(ADP-ribose) polymerase (PARP). We also examined nitric oxide (NO) production and nuclear staining. When BNL CL.2 cells were treated with G/GO (50 mU/ml), viability of the cells was 54.1%. However, the number of living cells after the addition of UDN glycoprotein in the presence of G/GO increased. UDN glycoprotein protected from cell damage caused by G/GO. Interestingly, UDN glycoprotein decreased NF-kappaB activation and stimulated NO production in G/GO-induced BNL CL.2 cells. In apoptotic parameters, UDN glycoprotein inhibited activations of caspase-3 and PARP cleavage in G/GO-induced BNL CL.2 cells. The results of nuclear staining indicated that UDN glycoprotein (50 microg/ml) has a protective ability from apoptotic cell death caused G/GO (50 mU/ml). In conclusion, UDN glycoprotein has a protective effect on apoptosis induced by G/GO through the inhibition of NF-kappaB, caspase-3, and PARP activity, and the stimulation of NO production in BNL CL.2 cells.

T cell-depleted splenocytes from mice pre-immunized with neuroantigen in incomplete Freund's adjuvant involved in protection from experimental autoimmune encephalomyelitis.

PubMed

Zheng, Hui; Zhang, Han; Liu, Feng; Qi, Yuanyuan; Jiang, Hong

2014-01-01

Mice immunized with neuroantigens in incomplete Freund's adjuvant (IFA) are resistant to subsequent induction of experimental autoimmune encephalomyelitis (EAE). The mechanisms involved in this protection are complex. Studies on relevant CD4(+) or CD8(+) T cells, including effective and regulatory T cells, have been performed by others. In this work, the effects of CD4(-)-, CD8(-)- splenocytes on protection from EAE in C57BL/6 mice which were immunized with myelin oligodendrocyte glycoprotein 35-55 (MOG)35-55 in IFA were evaluated. We observed that MOG-reactive CD4(+) T cells failed to be activated and proliferate when CD4(-)-, CD8(-)- splenocytes from MOG/IFA-immunized mice were regarded as antigen-presenting cells (APC). It was shown that these APC expressed lower levels of major histocompatibility complex class II (MHC-II), CD80, and CD86 than naïve cells. In addition, CD4(-)-, CD8(-)- splenocytes from MOG/IFA-immunized mice showed significantly higher levels of IL-10 mRNA expression. When the immunized-mice were induced to develop EAE, these cells secreted significantly higher levels of IL-10 and produced lower levels of IL-6, leading to decreased secretion of IL-17 and IFN-γ from MOG-specific CD4(+) T cells. The transfer of CD4(-)-, CD8(-)- splenocytes from MOG/IFA-immunized mice was able to ameliorate the subsequent induction of EAE in recipient mice. Thus, MOG/IFA immunization can modulate CD4(-)-, CD8(-)- splenocytes by reducing the expression of antigen-presenting molecules and altering the levels of secreted cytokines. Our study reveals an additional mechanism involved in the protective effects of MOG/IFA pre-immunization in an EAE model. Copyright © 2013 Elsevier B.V. All rights reserved.

Quercetin-3-O-α-l-arabinopyranoside protects against retinal cell death via blue light-induced damage in human RPE cells and Balb-c mice.

PubMed

Kim, Jun; Jin, Hong Lan; Jang, Dae Sik; Jeong, Kwang Won; Choung, Se-Young

2018-04-25

Age-related macular degeneration (AMD) is among the increasing number of diseases causing irreversible blindness in the elderly. Dry AMD is characterized by the accumulation of lipofuscin in retinal pigment epithelium (RPE) cells. N-Retinylidene-N-retinylethanolamine (A2E), a component of lipofuscin, is oxidized to oxo-A2E under blue light illumination, leading to retinal cell death. The aim of this study was to investigate the protective effect and mechanism of quercetin-3-O-α-l-arabinopyranoside (QA) against blue light (BL)-induced damage in both RPE cells and mice models. Treatment by QA inhibited A2E uptake in RPE cells, as determined by a decrease in fluorescence intensity. QA also protected A2E-laden RPE cells against BL-induced apoptosis. QA inhibited C3 complement activation and poly (ADP-ribose) polymerase (PARP) cleavage, as determined by western blotting. QA showed an inhibitory effect on AP1 and NF-kB activity as estimated in a reporter gene assay. In addition, QA activated the gene expression of aryl hydrocarbon receptor target genes (CYP1A1, CYP1B1) in TCDD-treated RPE cells. In the mice model, oral administration of QA protected against retinal degeneration induced by BL exposure as determined by histological analyses (thickness of retinal layers and immunostaining for caspase-3). In addition, QA inhibited apoptosis and inflammation via inhibition of NF-kB p65 translocation, C3 activation, and PARP cleavage. Collectively, these results revealed the protective mechanism of QA against BL-induced retinal damage both in vitro and in vivo.

The effect of a plasma needle on bacteria in planktonic samples and on peripheral blood mesenchymal stem cells

NASA Astrophysics Data System (ADS)

Lazović, Saša; Puač, Nevena; Miletić, Maja; Pavlica, Dušan; Jovanović, Milena; Bugarski, Diana; Mojsilović, Slavko; Maletić, Dejan; Malović, Gordana; Milenković, Pavle; Petrović, Zoran

2010-08-01

In this paper, we study the application of a plasma needle to induce necrosis in planktonic samples containing a single breed of bacteria. Two different types of bacteria, Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922), were covered in this study. In all experiments with bacteria, the samples were liquid suspensions of several different concentrations of bacteria prepared according to the McFarland standard. The second system studied in this paper was human peripheral blood mesenchymal stem cells (hPB-MSC). In the case of hPB-MSC, two sets of experiments were performed: when cells were covered with a certain amount of liquid (indirect) and when the cell sample was in direct contact with the plasma. Most importantly, the study is made with the aim to see the effects when the living cells are in a liquid medium, which normally acts as protection against the many agents that may be released by plasmas. It was found that a good effect may be expected for a wide range of initial cell densities and operating conditions causing destruction of several orders of magnitude even under the protection of a liquid. It was established independently that a temperature increase could not affect the cells under the conditions of our experiment, so the effect could originate only from the active species produced by the plasma. In the case of those hPB-MSC that were not protected by a liquid, gas flow proved to produce a considerable effect, presumably due to poor adhesion of the cells, but in a liquid the effect was only due to the plasma. Further optimization of the operation may be attempted, opening up the possibility of localized in vivo sterilization.

The Role of Pyruvate in Protecting 661W Photoreceptor-Like Cells Against Light-Induced Cell Death.

PubMed

Natoli, Riccardo; Rutar, Matt; Lu, Yen-Zhen; Chu-Tan, Joshua A; Chen, Yuwei; Saxena, Kartik; Madigan, Michele; Valter, Krisztina; Provis, Jan M

2016-11-01

Light is a requirement for the function of photoreceptors in visual processing. However, prolonged light exposure can be toxic to photoreceptors, leading to increased reactive oxygen species (ROS), lipid peroxidation, and photoreceptor cell death. We used the 661W mouse cone photoreceptor-like cell line to study the effects of pyruvate in protecting these cells from light-induced toxicity. 661W cells were exposed to 15,000 lux continuous bright light for 5 hours and incubated in Dulbecco's modified eagle medium (DMEM) with various concentrations of pyruvate. Following light damage, cells were assessed for changes in morphology, cell toxicity, viability, and ROS production. Mitochondrial respiration and anaerobic glycolysis were also assessed using a Seahorse Xfe96 extracellular flux analyzer. We found that cell death caused by light damage in 661W cells was dramatically reduced in the presence of pyruvate. Cells with pyruvate-supplemented media also showed attenuation of oxidative stress and maintained normal levels of ATP. We also found that alterations in the concentrations of pyruvate had no effect on mitochondrial respiration or glycolysis in light-damaged cells. Taken together, the results show that pyruvate is protective against light damage but does not alter the metabolic output of the cells, indicating an alternative role for pyruvate in reducing oxidative stress. Thus, sodium pyruvate is a possible candidate for the treatment against the oxidative stress component of retinal degenerations.

In vitro protective effects of botryosphaeran, a (1→3;1→6)-β-d-glucan, against mutagens in normal and tumor rodent cells.

PubMed

Kerche-Silva, Leandra E; Cólus, Ilce M S; Malini, Maressa; Mori, Mateus Prates; Dekker, Robert F H; Barbosa-Dekker, Aneli M

2017-02-01

Botryosphaeran (BOT) is an exocellular β-d-glucan (carbohydrate biopolymer) of the (1→3;1→6)-linked type produced by Botryosphaeria rhodina MAMB-05. The cytotoxic, mutagenic, genotoxic, and protective effects of this substance were evaluated in Chinese hamster lung fibroblasts (V79) and rat hepatocarcinoma cells (HTC) by the micronucleus test (MN) and the comet assay. BOT was not genotoxic in either cell line; it decreased the clastogenic effects of doxorubicin, H 2 O 2 , and benzo[a]pyrene. These results indicate that BOT may have potential as a therapeutic agent. Copyright © 2016 Elsevier B.V. All rights reserved.

State transitions and physicochemical aspects of cryoprotection and stabilization in freeze-drying of Lactobacillus rhamnosus GG (LGG).

PubMed

Pehkonen, K S; Roos, Y H; Miao, S; Ross, R P; Stanton, C

2008-06-01

The frozen and dehydrated state transitions of lactose and trehalose were determined and studied as factors affecting the stability of probiotic bacteria to understand physicochemical aspects of protection against freezing and dehydration of probiotic cultures. Lactobacillus rhamnosus GG was frozen (-22 or -43 degrees C), freeze-dried and stored under controlled water vapour pressure (0%, 11%, 23% and 33% relative vapour pressure) conditions. Lactose, trehalose and their mixture (1 : 1) were used as protective media. These systems were confirmed to exhibit relatively similar state transition and water plasticization behaviour in freeze-concentrated and dehydrated states as determined by differential scanning calorimetry. Ice formation and dehydrated materials were studied using cold-stage microscopy and scanning electron microscopy. Trehalose and lactose-trehalose gave the most effective protection of cell viability as observed from colony forming units after freezing, dehydration and storage. Enhanced cell viability was observed when the freezing temperature was -43 degrees C. State transitions of protective media affect ice formation and cell viability in freeze-drying and storage. Formation of a maximally freeze-concentrated matrix with entrapped microbial cells is essential in freezing prior to freeze-drying. Freeze-drying must retain a solid amorphous state of protectant matrices. Freeze-dried matrices contain cells entrapped in the protective matrices in the freezing process. The retention of viability during storage seems to be controlled by water plasticization of the protectant matrix and possibly interactions of water with the dehydrated cells. Highest cell viability was obtained in glassy protective media. This study shows that physicochemical properties of protective media affect the stability of dehydrated cultures. Trehalose and lactose may be used in combination, which is particularly important for the stabilization of probiotic bacteria in dairy systems.

Beneficial effect of the bioflavonoid quercetin on cholecystokinin-induced mitochondrial dysfunction in isolated rat pancreatic acinar cells.

PubMed

Weber, Heike; Jonas, Ludwig; Wakileh, Michael; Krüger, Burkhard

2014-03-01

The pathogenesis of acute pancreatitis (AP) is still poorly understood. Thus, a reliable pharmacological therapy is currently lacking. In recent years, an impairment of the energy metabolism of pancreatic acinar cells, caused by Ca(2+)-mediated depolarization of the inner mitochondrial membrane and a decreased ATP supply, has been implicated as an important pathological event. In this study, we investigated whether quercetin exerts protection against mitochondrial dysfunction. Following treatment with or without quercetin, rat pancreatic acinar cells were stimulated with supramaximal cholecystokinin-8 (CCK). CCK caused a decrease in the mitochondrial membrane potential (MMP) and ATP concentration, whereas the mitochondrial dehydrogenase activity was significantly increased. Quercetin treatment before CCK application exerted no protection on MMP but increased ATP to a normal level, leading to a continuous decrease in the dehydrogenase activity. The protective effect of quercetin on mitochondrial function was accompanied by a reduction in CCK-induced changes to the cell membrane. Concerning the molecular mechanism underlying the protective effect of quercetin, an increased AMP/ATP ratio suggests that the AMP-activated protein kinase system may be activated. In addition, quercetin strongly inhibited CCK-induced trypsin activity. The results indicate that the use of quercetin may be a therapeutic strategy for reducing the severity of AP.

Coenzyme Q{sub 10} and alpha-tocopherol protect against amitriptyline toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cordero, Mario D.; Dpto. Citologia e Histologia Normal y Patologica, Facultad de Medicina. Universidad de Sevilla. 41009 Sevilla; Moreno-Fernandez, Ana Maria

Since amitriptyline is a very frequently prescribed antidepressant drug, it is not surprising that amitriptyline toxicity is relatively common. Amitriptyline toxic systemic effects include cardiovascular, autonomous nervous, and central nervous systems. To understand the mechanisms of amitriptyline toxicity we studied the cytotoxic effects of amitriptyline treatment on cultured primary human fibroblasts and zebrafish embryos, and the protective role of coenzyme Q{sub 10} and alpha-tocopherol, two membrane antioxidants. We found that amitriptyline treatment induced oxidative stress and mitochondrial dysfunction in primary human fibroblasts. Mitochondrial dysfunction in amitriptyline treatment was characterized by reduced expression levels of mitochondrial proteins and coenzyme Q{sub 10},more » decreased NADH:cytochrome c reductase activity, and a drop in mitochondrial membrane potential. Moreover, and as a consequence of these toxic effects, amitriptyline treatment induced a significant increase in apoptotic cell death activating mitochondrial permeability transition. Coenzyme Q{sub 10} and alpha-tocopherol supplementation attenuated ROS production, lipid peroxidation, mitochondrial dysfunction, and cell death, suggesting that oxidative stress affecting cell membrane components is involved in amitriptyline cytotoxicity. Furthermore, amitriptyline-dependent toxicity and antioxidant protection were also evaluated in zebrafish embryos, a well established vertebrate model to study developmental toxicity. Amitriptyline significantly increased embryonic cell death and apoptosis rate, and both antioxidants provided a significant protection against amitriptyline embryotoxicity.« less

Targeting Oct2 and P53: Formononetin prevents cisplatin-induced acute kidney injury.

PubMed

Huang, Di; Wang, Chuangyuan; Duan, Yingjie; Meng, Qiang; Liu, Zhihao; Huo, Xiaokui; Sun, Huijun; Ma, Xiaodong; Liu, Kexin

2017-07-01

Nephrotoxicity is one of major side effects of cisplatin in chemotherapy. Therefore, there is an urgent medical need to develop drugs that may protect kidney from toxicity. In previous study, we found that it showed the protective effects of formononetin against apoptosis by upregulating Nrf2. In this study, we investigated the renoprotective effect of formononetin against cisplatin-induced AKI and tried to elucidate the possible mechanisms. The amelioration of renal function, histopathological changes, and apoptosis in tubular cells was observed after formononetin treatment. Formononetin decreased expression of organic cation transporter 2 (Oct2) and increased the expressions of multidrug resistance-associated proteins (Mrps), which might result in a decrease accumulation of cisplatin in tubular cells after AKI. 5-Bromo-2-deoxyuridine (BrdU) and Ki-67 staining assay indicated that formononetin could promote the renal tubular cells proliferation after cisplatin nephrotoxicity. Moreover, formononetin regulated cyclins and pro-apoptotic proteins to involve the regulation of cell cycle. Furthermore, formononetin decreased p53 expression via promoting the overexpression of murine double minute 2 (MDM2) and MDMX. Taken together, formononetin provided protective effects by promoting proliferation of surviving renal tubular cells and inhibiting apoptosis after cisplatin-induced AKI. Copyright © 2017 Elsevier Inc. All rights reserved.

Spirulina Extract Enhanced a Protective Effect in Type 1 Diabetes by Anti-Apoptosis and Anti-ROS Production

PubMed Central

Lee, Jiyeong; Park, Arum; Kim, Mi Jeong; Lim, Hee-Joung; Rha, Young-Ah

2017-01-01

Interest in the nutritional value and pharmacological activities of blue-green algae has gradually increased. Spirulina extracts show protective effects against apoptosis and inflammatory damage in various cell types. Here, we investigated the protective effects of extracts from Spirulina maxima in a cytokine-mediated type 1 diabetes model in vitro and in streptozotocin-induced diabetic Wistar rats in vivo. Interleukin-1β and interferon-gamma induced substantial cytotoxicity to RINm5F rat insulinoma cells, increasing nitric oxide (NO) production, nuclear factor-kappa B (NF-κB) activity, the expression of endoplasmic reticulum (ER) stress genes, and activation of mitogen-activated protein kinases and key genes related apoptosis. However, the cytotoxicity of cytokines was significantly attenuated by Spirulina extract, which effectively prevented NO production by inhibiting the synthesis of cytokine-activated NO synthase (iNOS), and apoptosis was suppressed. These results suggest that Spirulina extract might be effective to preserve the viability and function of pancreatic β-cells against cytotoxic conditions. Moreover, diabetic mice orally administered Spirulina extract showed decreased glucose levels, increased insulin, and improvement in liver enzyme markers. The antioxidant effect of Spirulina extract may be helpful in treating type 1 diabetes by enhancing the survival, and reducing or delaying cytokine-mediated β-cells destruction. PMID:29244751

Ursodeoxycholic acid protects cardiomyocytes against cobalt chloride induced hypoxia by regulating transcriptional mediator of cells stress hypoxia inducible factor 1α and p53 protein.

PubMed

Mohamed, Anis Syamimi; Hanafi, Noorul Izzati; Sheikh Abdul Kadir, Siti Hamimah; Md Noor, Julina; Abdul Hamid Hasani, Narimah; Ab Rahim, Sharaniza; Siran, Rosfaiizah

2017-10-01

In hepatocytes, ursodeoxycholic acid (UDCA) activates cell signalling pathways such as p53, intracellular calcium ([Ca 2+ ] i ), and sphingosine-1-phosphate (S1P)-receptor via Gα i -coupled-receptor. Recently, UDCA has been shown to protect the heart against hypoxia-reoxygenation injury. However, it is not clear whether UDCA cardioprotection against hypoxia acts through a transcriptional mediator of cells stress, HIF-1α and p53. Therefore, in here, we aimed to investigate whether UDCA could protect cardiomyocytes (CMs) against hypoxia by regulating expression of HIF-1α, p53, [Ca 2+ ] i , and S1P-Gα i -coupled-receptor. Cardiomyocytes were isolated from newborn rats (0-2 days), and hypoxia was induced by using cobalt chloride (CoCl 2 ). Cardiomyocytes were treated with UDCA and cotreated with either FTY720 (S1P-receptor agonist) or pertussis toxin (PTX; Gα i inhibitor). Cells were subjected for proliferation assay, beating frequency, QuantiGene Plex assay, western blot, immunofluorescence, and calcium imaging. Our findings showed that UDCA counteracted the effects of CoCl 2 on cell viability, beating frequency, HIF-1α, and p53 protein expression. We found that these cardioprotection effects of UDCA were similar to FTY720, S1P agonist. Furthermore, we observed that UDCA protects CMs against CoCl 2 -induced [Ca 2+ ] i dynamic alteration. Pharmacological inhibition of the Gα i -sensitive receptor did not abolish the cardioprotection of UDCA against CoCl 2 detrimental effects, except for cell viability and [Ca 2+ ] i . Pertussis toxin is partially effective in inhibiting UDCA protection against CoCl 2 effects on CM cell viability. Interestingly, PTX fully inhibits UDCA cardioprotection on CoCl 2 -induced [Ca 2+ ] i dynamic changes. We conclude that UDCA cardioprotection against CoCl 2 -induced hypoxia is similar to FTY720, and its actions are not fully mediated by the Gα i -coupled protein sensitive pathways. Ursodeoxycholic acid is the most hydrophilic bile acid and is currently used to treat liver diseases. Recently, UDCA is shown to have a cardioprotection effects; however, the mechanism of UDCA cardioprotection is still poorly understood. The current data generated were the first to show that UDCA is able to inhibit the activation of HIF-1α and p53 protein during CoCl 2 -induced hypoxia in cardiomyocytes. This study provides an insight of UDCA mechanism in protecting cardiomyocytes against hypoxia. Copyright © 2017 John Wiley & Sons, Ltd.

Role of natural killer cells in innate protection against lethal ebola virus infection.

PubMed

Warfield, Kelly L; Perkins, Jeremy G; Swenson, Dana L; Deal, Emily M; Bosio, Catharine M; Aman, M Javad; Yokoyama, Wayne M; Young, Howard A; Bavari, Sina

2004-07-19

Ebola virus is a highly lethal human pathogen and is rapidly driving many wild primate populations toward extinction. Several lines of evidence suggest that innate, nonspecific host factors are potentially critical for survival after Ebola virus infection. Here, we show that nonreplicating Ebola virus-like particles (VLPs), containing the glycoprotein (GP) and matrix protein virus protein (VP)40, administered 1-3 d before Ebola virus infection rapidly induced protective immunity. VLP injection enhanced the numbers of natural killer (NK) cells in lymphoid tissues. In contrast to live Ebola virus, VLP treatment of NK cells enhanced cytokine secretion and cytolytic activity against NK-sensitive targets. Unlike wild-type mice, treatment of NK-deficient or -depleted mice with VLPs had no protective effect against Ebola virus infection and NK cells treated with VLPs protected against Ebola virus infection when adoptively transferred to naive mice. The mechanism of NK cell-mediated protection clearly depended on perforin, but not interferon-gamma secretion. Particles containing only VP40 were sufficient to induce NK cell responses and provide protection from infection in the absence of the viral GP. These findings revealed a decisive role for NK cells during lethal Ebola virus infection. This work should open new doors for better understanding of Ebola virus pathogenesis and direct the development of immunotherapeutics, which target the innate immune system, for treatment of Ebola virus infection.

Quercetin Potentiates Doxorubicin Mediated Antitumor Effects against Liver Cancer through p53/Bcl-xl

PubMed Central

Wang, Guanyu; Sharma, Sherven; Dong, Qinghua

2012-01-01

Background The dose-dependent toxicities of doxorubicin (DOX) limit its clinical applications, particularly in drug-resistant cancers, such as liver cancer. In this study, we investigated the role of quercetin on the antitumor effects of DOX on liver cancer cells and its ability to provide protection against DOX-mediated liver damage in mice. Methodology and Results The MTT and Annexin V/PI staining assay demonstrated that quercetin selectively sensitized DOX-induced cytotoxicity against liver cancer cells while protecting normal liver cells. The increase in DOX-mediated apoptosis in hepatoma cells by quercetin was p53-dependent and occurred by downregulating Bcl-xl expression. Z-VAD-fmk (caspase inhibitor), pifithrin-α (p53 inhibitor), or overexpressed Bcl-xl decreased the effects of quercetin on DOX-mediated apoptosis. The combined treatment of quercetin and DOX significantly reduced the growth of liver cancer xenografts in mice. Moreover, quercetin decreased the serum levels of alanine aminotransferase and aspartate aminotransferase that were increased in DOX-treated mice. Quercetin also reversed the DOX-induced pathological changes in mice livers. Conclusion and Significance These results indicate that quercetin potentiated the antitumor effects of DOX on liver cancer cells while protecting normal liver cells. Therefore, the development of quercetin may be beneficial in a combined treatment with DOX for increased therapeutic efficacy against liver cancer. PMID:23240061

Nrf2 protects human bladder urothelial cells from arsenite and monomethylarsonous acid toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang Xiaojun; Sun Zheng; Chen Weimin

2007-12-01

Arsenic is widely spread in our living environment and imposes a big challenge on human health worldwide. Arsenic damages biological systems through multiple mechanisms including the generation of reactive oxygen species. The transcription factor Nrf2 regulates the cellular antioxidant response that protects cells from various insults. In this study, the protective role of Nrf2 in arsenic toxicity was investigated in a human bladder urothelial cell line, UROtsa. Using a UROtsa cell line stably infected with Nrf2-siRNA, we clearly demonstrate that compromised Nrf2 expression sensitized the cells to As(III)- and MMA(III)-induced toxicity. On the other hand, the activation of the Nrf2more » pathway by tert-butylhydroquinone (tBHQ) and sulforaphane (SF), the known Nrf2-inducers, rendered UROtsa cells more resistant to As(III) and MMA(III). Furthermore, the wild-type mouse embryo fibroblast (WT-MEF) cells were protected from As(III)- and MMA(III)-induced toxicity following Nrf2 activation by tBHQ or SF, whereas neither tBHQ nor SF conferred protection in the Nrf2{sup -/-}MEF cells, demonstrating that tBHQ- or SF-mediated protection against As(III)- and MMA(III)-induced toxicity depends on Nrf2 activation. These results, obtained by both loss of function and gain of function analyses, clearly demonstrate the protective role of Nrf2 in arsenic-induced toxicity. The current work lays the groundwork for using Nrf2 activators for therapeutic and dietary interventions against adverse effects of arsenic.« less

Size is an essential parameter in governing the UVB-protective efficacy of silver nanoparticles in human keratinocytes.

PubMed

Palanki, Rohan; Arora, Sumit; Tyagi, Nikhil; Rusu, Lilia; Singh, Ajay P; Palanki, Srinivas; Carter, James E; Singh, Seema

2015-09-15

Ultraviolet (UV) radiation from sun, particularly its UVB component (290-320 nm), is considered the major etiological cause of skin cancer that impacts over 2 million lives in the United States alone. Recently, we reported that polydisperse colloidal suspension of silver nanoparticles (AgNPs) protected the human keratinocytes (HaCaT) against UVB-induced damage, thus indicating their potential for prevention of skin carcinogenesis. Here we sought out to investigate if size controlled the chemopreventive efficacy of AgNPs against UVB-induced DNA damage and apoptosis. Percent cell viability was examined by WST-1 assay after treating the cells with various doses (1-10 μg/mL) of AgNPs of different sizes (10, 20, 40, 60 and 100 nm) for 12 and 24 h. For protection studies, cells were treated with AgNPs of different sizes at a uniform concentration of 1 μg/mL. After 3 h, cells were irradiated with UVB (40 mJ/cm(2)) and dot-blot analysis was performed to detect cyclobutane pyrimidine dimers (CPDs) as an indication of DNA damage. Apoptosis was analyzed by flow cytometry after staining the cells with 7-Amino-Actinomycin (7-AAD) and PE Annexin V. Immunoblot analysis was accomplished by processing the cells for protein extraction and Western blotting using specific antibodies against various proteins. The data show that the pretreatment of HaCaT cells with AgNPs in the size range of 10-40 nm were effective in protecting the skin cells from UVB radiation-induced DNA damage as validated by reduced amounts of CPDs, whereas no protection was observed with AgNPs of larger sizes (60 and 100 nm). Similarly, only smaller size AgNPs (10-40 nm) were effective in protecting the skin cells from UV radiation-induced apoptosis. At the molecular level, UVB -irradiation of HaCaT cells led to marked increase in expression of pro-apoptotic protein (Bax) and decrease in anti-apoptotic proteins (Bcl-2 and Bcl-xL), while it remained largely unaffected in skin cells pretreated with smaller size AgNPs (10-40 nm). Altogether, these findings suggest that size is a critical determinant of the UVB-protective efficacy of AgNPs in human keratinocytes.

Activation of KGFR-Akt-mTOR-Nrf2 signaling protects human retinal pigment epithelium cells from Ultra-violet.

PubMed

Hu, Haitao; Hao, Lanxiang; Tang, Chunzhou; Zhu, Yunxi; Jiang, Qin; Yao, Jin

2018-01-15

Ultra-violet (UV) radiation causes oxidative injuries to human retinal pigment epithelium (RPE) cells. We tested the potential effect of keratinocyte growth factor (KGF) against the process. KGF receptor (KGFR) is expressed in ARPE-19 cells and primary human RPE cells. Pre-treatment with KGF inhibited UV-induced reactive oxygen species (ROS) production and RPE cell death. KGF activated nuclear-factor-E2-related factor 2 (Nrf2) signaling in RPE cells, causing Nrf2 Ser-40 phosphorylation, stabilization and nuclear translocation as well as expression of Nrf2-dependent genes (HO1, NOQ1 and GCLC). Nrf2 knockdown (by targeted shRNAs) or S40T mutation almost reversed KGF-induced RPE cell protection against UV. Further studies demonstrated that KGF activated KGFR-Akt-mTORC1 signaling to mediate downstream Nrf2 activation. KGFR shRNA or Akt-mTORC1 inhibition not only blocked KGF-induced Nrf2 Ser-40 phosphorylation and activation, but also nullified KGF-mediated RPE cell protection against UV. We conclude that KGF-KGFR activates Akt-mTORC1 downstream Nrf2 signaling to protect RPE cells from UV radiation. Copyright © 2017 Elsevier Inc. All rights reserved.

Protective effects of anethole dithiolethione against oxidative stress-induced cytotoxicity in human Jurkat T cells.

PubMed

Khanna, S; Sen, C K; Roy, S; Christen, M O; Packer, L

1998-07-01

The protective effects of anethole dithiolethione (ADT) against H2O2- or 4-hydroxynonenal (HNE)-induced cytotoxicity in human Jurkat T cells were investigated. Jurkat T cells were pretreated with ADT (10-50 microM) for 18 hr and then challenged with H202 or HNE for up to 4 hr. Cytotoxicity was assessed by measuring: 1) leakage of lactate dehydrogenase from cells to medium; and 2) exclusion of the DNA intercalating fluorescent probe propidium iodide by viable cells. Pretreatment of cells with ADT (10 or 25 microM) for 18 hr significantly protected cells against H202- or HNE-induced cytotoxicity. Treatment of cells with ADT (10-50 microM) for 72 hr significantly increased the activities of catalase and glutathione reductase. The maximum effect of ADT treatment on the activity of these enzymes was observed when cells were treated with 25 microM of ADT for 72 hr. A significant increase in cellular GSH was observed in cells that were treated with ADT for 72 hr. Using monobromobimane as a thiol probe, we consistently observed that cells pretreated for 18 hr with ADT (25 or 50 microM) had also increased total thiol content. Exposure of Jurkat T cells to H202 or HNE resulted in a time-dependent decrease in cellular GSH. ADT (10-50 microM, 18 hr) pretreatment circumvented H202-dependent lowering of cellular GSH. In conclusion, ADT proved to be a potent cytoprotective thiol antioxidant with multifaceted mechanisms of action, suggesting that the drug has a remarkable therapeutic potential.

A single vaccination with non-replicating MVA at birth induces both immediate and long-term protective immune responses.

PubMed

Cheminay, Cédric; Körner, Jana; Bernig, Constanze; Brückel, Michael; Feigl, Markus; Schletz, Martin; Suter, Mark; Chaplin, Paul; Volkmann, Ariane

2018-04-25

Newborns are considered difficult to protect against infections shortly after birth, due to their ineffective immune system that shows quantitative and qualitative differences compared to adults. However, here we show that a single vaccination of mice at birth with a replication-deficient live vaccine Modified Vaccinia Ankara [MVA] efficiently induces antigen-specific B- and T-cells that fully protect against a lethal Ectromelia virus challenge. Protection was induced within 2 weeks and using genetically modified mice we show that this protection was mainly T-cell dependent. Persisting immunological T-cell memory and neutralizing antibodies were obtained with the single vaccination. Thus, MVA administered as early as at birth induced immediate and long-term protection against an otherwise fatal disease and appears attractive as a new generation smallpox vaccine that is effective also in children. Moreover, it may have the potential to serve as platform for childhood vaccines as indicated by measles specific T- and B-cell responses induced in newborn mice vaccinated with recombinant MVA expressing measles antigens. Copyright © 2018 Elsevier Ltd. All rights reserved.

Potentiation of lead-induced cell death in PC12 cells by glutamate: Protection by N-acetylcysteine amide (NACA), a novel thiol antioxidant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Penugonda, Suman; Mare, Suneetha; Lutz, P.

2006-10-15

Oxidative stress has been implicated as an important factor in many neurological diseases. Oxidative toxicity in a number of these conditions is induced by excessive glutamate release and subsequent glutamatergic neuronal stimulation. This, in turn, causes increased generation of reactive oxygen species (ROS), oxidative stress, excitotoxicity, and neuronal damage. Recent studies indicate that the glutamatergic neurotransmitter system is involved in lead-induced neurotoxicity. Therefore, this study aimed to (1) investigate the potential effects of glutamate on lead-induced PC12 cell death and (2) elucidate whether the novel thiol antioxidant N-acetylcysteine amide (NACA) had any protective abilities against such cytotoxicity. Our results suggestmore » that glutamate (1 mM) potentiates lead-induced cytotoxicity by increased generation of ROS, decreased proliferation (MTS), decreased glutathione (GSH) levels, and depletion of cellular adenosine-triphosphate (ATP). Consistent with its ability to decrease ATP levels and induce cell death, lead also increased caspase-3 activity, an effect potentiated by glutamate. Exposure to glutamate and lead elevated the cellular malondialdehyde (MDA) levels and phospholipase-A{sub 2} (PLA{sub 2}) activity and diminished the glutamine synthetase (GS) activity. NACA protected PC12 cells from the cytotoxic effects of glutamate plus lead, as evaluated by MTS assay. NACA reduced the decrease in the cellular ATP levels and restored the intracellular GSH levels. The increased levels of ROS and MDA in glutamate-lead treated cells were significantly decreased by NACA. In conclusion, our data showed that glutamate potentiated the effects of lead-induced PC12 cell death by a mechanism involving mitochondrial dysfunction (ATP depletion) and oxidative stress. NACA had a protective role against the combined toxic effects of glutamate and lead by inhibiting lipid peroxidation and scavenging ROS, thus preserving intracellular GSH.« less

Protective effect of insulin and glucose at different concentrations on penicillin-induced astrocyte death on the primer astroglial cell line☆

PubMed Central

Özdemir, Mehmet Bülent; Akça, Hakan; Erdoğan, Çağdaş; Tokgün, Onur; Demiray, Aydın; Semin, Fenkçi; Becerir, Cem

2012-01-01

Astrocytes perform many functions in the brain and spinal cord. Glucose metabolism is important for astroglial cells and astrocytes are the only cells with insulin receptors in the brain. The common antibiotic penicillin is also a chemical agent that causes degenerative effect on neuronal cell. The aim of this study is to show the effect of insulin and glucose at different concentrations on the astrocyte death induced by penicillin on primer astroglial cell line. It is well known that intracranial penicillin treatment causes neuronal cell death and it is used for experimental epilepsy model commonly. Previous studies showed that insulin and glucose might protect neuronal cell in case of proper concentrations. But, the present study is about the effect of insulin and glucose against astrocyte death induced by penicillin. For this purpose, newborn rat brain was extracted and then mechanically dissociated to astroglial cell suspension and finally grown in culture medium. Clutters were maintained for 2 weeks prior to being used in these experiments. Different concentrations of insulin (0, 1, 3 nM) and glucose (0, 3, 30 mM) were used in media without penicillin and with 2 500 μM penicillin. Penicillin decreased the viability of astroglial cell seriously. The highest cell viability appeared in medium with 3 nM insulin and 3 mM glucose but without penicillin. However, in medium with penicillin, the best cell survival was in medium with 1 nM insulin but without glucose. We concluded that insulin and glucose show protective effects on the damage induced by penicillin to primer astroglial cell line. Interestingly, cell survival depends on concentrations of insulin and glucose strongly. The results of this study will help to explain cerebrovascular pathologies parallel to insulin and glucose conditions of patient after intracranial injuries. PMID:25624816

Ginkgolide B Reduces LOX-1 Expression by Inhibiting Akt Phosphorylation and Increasing Sirt1 Expression in Oxidized LDL-Stimulated Human Umbilical Vein Endothelial Cells

PubMed Central

Chen, Beidong; Li, Xingguang; Qi, Ruomei

2013-01-01

Oxidized low-density lipoprotein (ox-LDL) is an important risk factor in the development of atherosclerosis. LOX-1, a lectin-like receptor for ox-LDL, is present primarily on endothelial cells and upregulated by ox-LDL, tumor necrosis factor a, shear stress, and cytokines in atherosclerosis. Recent studies demonstrated that ginkgolide B, a platelet-activating factor receptor antagonist, has antiinflammatory and antioxidant effects on endothelial and nerve cells. The present study investigated the effects of ginkgolide B on LOX-1 expression and the possible mechanism of action. Our results showed that ginkgolide B inhibited LOX-1 and intercellular cell adhesion molecule-1 (ICAM-1) expression in ox-LDL-stimulated endothelial cells through a mechanism associated with the attenuation of Akt activation. Similar data were obtained by silencing Akt and LY294002. We also evaluated Sirt1 and nuclear factor erythroid 2-related factor 2 (Nrf2) expression. These molecules play a protective role in endothelial cell injury. The results showed that ginkgolide B increased Sirt1 expression in ox-LDL-treated cells. The inhibitory effects of ginkgolide B on LOX-1 and ICAM-1 expression were reduced in Sirt1 siRNA-transfected cells. Nrf2 expression was increased in ox-LDL-treated cells, and ginkgolide B downregulated Nrf2 expression. These results suggest that ginkgolide B reduces Nrf2 expression by inhibiting LOX-1 expression, consequently reducing oxidative stress injury in ox-LDL-stimulated cells. Altogether, these results indicate that the protective effect of ginkgolide B on endothelial cells may be attributable to a decrease in LOX-1 expression and an increase in Sirt1 expression in ox-LDL-stimulated endothelial cells, the mechanism of which is linked to the inhibition of Akt activation. Ginkgolide B may be a multiple-target drug that exerts protective effects in ox-LDL-treated human umbilical vein endothelial cells. PMID:24069345

Methamphetamine induces apoptosis in immortalized neural cells: protection by the proto-oncogene, bcl-2.

PubMed

Cadet, J L; Ordonez, S V; Ordonez, J V

1997-02-01

Methamphetamine (METH) is an amphetamine analog that produces degeneration of the dopaminergic system in mammals. The neurotoxic effects of the drug are thought to be mediated by oxygen-based free radicals. In the present report, we have used immortalized neural cells obtained from rat mesencephalon in order to further assess the role of oxidative stress in METH-induced neurotoxicity. We thus tested if the anti-death proto-oncogene, bcl-2 could protect against METH-induced cytotoxicity. METH caused dose-dependent loss of cellular viability in control cells while bcl-2-expressing cells were protected against these deleterious effects. Using flow cytometry, immunofluorescent staining, and DNA electrophoresis, we also show that METH exposure can cause DNA strand breaks, chromatin condensation, nuclear fragmentation, and DNA laddering. All these changes were prevented by bcl-2 expression. These observations provide further support for the involvement of oxidative stress in the toxic effects of amphetamine analogs. They also document that METH-induced cytotoxicity is secondary to apoptosis. These findings may be of relevance to the cause(s) of Parkinson's disease which involves degeneration of the nigrostriatal dopaminergic pathway.

The effects of ebselen on cisplatin and diethyldithiocarbamate (DDC) cytotoxicity in rat hippocampal astrocytes.

PubMed

Hardej, D; Trombetta, L D

2002-05-28

Ebselen is a seleno-organic compound with documented cytoprotective properties. Little work has been done, however, demonstrating ebselen's cytoprotective properties in neural cell lines. In order to examine the effects of this compound and its mechanism of action, astrocytes were exposed to two known neurotoxicants, cisplatin and diethyldithiocarbamate (DDC). Cells were pretreated with 30 microM ebselen and subsequently treated with either 150 microM DDC for 1 h or 250 and 500 microM cisplatin for 24 h. Results indicate significant increases in viability in cells pretreated with ebselen and exposed to cisplatin. Ebselen pretreatment did not significantly increase viability in cells exposed to DDC. Light and scanning electron microscopy studies confirm the viability studies. Gross morphological damage was seen in cells treated with cisplatin, however, cells pretreated with ebselen and then exposed to cisplatin, appeared similar to controls. No differences were noted in cells pretreated with ebselen and then exposed to DDC or cells treated with DDC alone. In order to examine the mechanism of protection of this compound, glutathione status was examined. Results show that ebselen does not significantly increase reduced or oxidized glutathione (GSH, GSSG). All cell groups treated with cisplatin showed an increase in GSH levels. Ebselen showed protection in glutathione depleted cells at the 250 microM cisplatin dose. DDC treatment showed no significant increase in either reduced or oxidized glutathione. We conclude that ebselen significantly protects against cisplatin, but not DDC toxicity. We further conclude that this protection is not related to changes in glutathione status in the rat hippocampal cell line as has been reported in other cell types.

Neurotoxicity induced by dexamethasone in the human neuroblastoma SH-SY5Y cell line can be prevented by folic acid.

PubMed

Budni, J; Romero, A; Molz, S; Martín-de-Saavedra, M D; Egea, J; Del Barrio, L; Tasca, C I; Rodrigues, A L S; López, M G

2011-09-08

Folic acid (folate) is a vitamin of the B-complex group that is essential for cell replication. Folate is a major determinant of one-carbon metabolism, in which S-adenosylmethionine donates methyl groups that are crucial for neurological function. Many roles for folic acid have been reported, including neuroprotective and antidepressant properties. On the other hand, increased concentrations of corticoids have proven neurotoxic effects and hypersecretion of glucocorticoids has been linked to different mood disorders. The purpose of this study was to investigate the potential protective effect of folic acid on dexamethasone-induced cellular death in SH-SY5Y neuroblastoma cell line and the possible intracellular signaling pathway involved in such effect. Exposure to 1 mM dexamethasone for 48 h caused a significant reduction of cell viability measured as 3-[4,5 dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) reduction. Exposure of SH-SY5Y cells for 72 h to increasing concentrations of folate (1-300 μM) was not cytotoxic. However, pretreatment with folate (10-300 μM) reduced dexamethasone-induced toxicity in a significant manner. To explore the putative intracellular signaling pathways implicated in the protective effect of folate we used different protein kinase inhibitors. The protective effect of folic acid on dexamethasone-induced neurotoxicity was reversed by the phosphatidylinositol-3 kinase/Akt (PI3K/Akt, LY294002), Ca²⁺/Calmodulin-dependent protein kinase II (CaMKII, KN-93), and protein kinase A (PKA, H-89) inhibitors, but not the mitogen-activated protein/extracellular signal-regulated kinase (MEK1/2, PD98059) and protein kinase C (PKC, chelerythrine) inhibitors. In conclusion, the results of this study show that folic acid can protect against dexamethasone-induced neurotoxicity and its protective mechanism is related to a signaling pathway that involves PI3K/Akt, CaMKII, and PKA. Copyright © 2011. Published by Elsevier Ltd.

Protective effect of T-type calcium channel blocker flunarizine on cisplatin-induced death of auditory cells.

PubMed

So, Hong-Seob; Park, Channy; Kim, Hyung-Jin; Lee, Jung-Han; Park, Sung-Yeol; Lee, Jai-Hyung; Lee, Zee-Won; Kim, Hyung-Min; Kalinec, Federico; Lim, David J; Park, Raekil

2005-06-01

Changes in intracellular Ca2+ level are involved in a number of intracellular events, including triggering of apoptosis. The role of intracellular calcium mobilization in cisplatin-induced hair cell death, however, is still unknown. In this study, the effect of calcium channel blocker flunarizine (Sibelium), which is used to prescribe for vertigo and tinnitus, on cisplatin-induced hair cell death was investigated in a cochlear organ of Corti-derived cell line, HEI-OC1, and the neonatal (P2) rat organ of Corti explant. Cisplatin induced apoptotic cell death showing nuclear fragmentation, DNA ladder, and TUNEL positive in both HEI-OC1 and primary organ of Corti explant. Flunarizine significantly inhibited the cisplatin-induced apoptosis. Unexpectedly, flunarizine increased the intracellular calcium ([Ca2+]i) levels of HEI-OC1. However, the protective effect of flunarizine against cisplatin was not mediated by modulation of intracellular calcium level. Treatment of cisplatin resulted in ROS generation and lipid peroxidation in HEI-OC1. Flunarizine did not attenuate ROS production but inhibited lipid peroxidation and mitochondrial permeability transition in cisplatin-treated cells. This result suggests that the protective mechanism of flunarizine on cisplatin-induced cytotoxicity is associated with direct inhibition of lipid peroxidation and mitochondrial permeability transition.

Predominant role of DNA polymerase eta and p53-dependent translesion synthesis in the survival of ultraviolet-irradiated human cells.

PubMed

Lerner, Leticia K; Francisco, Guilherme; Soltys, Daniela T; Rocha, Clarissa R R; Quinet, Annabel; Vessoni, Alexandre T; Castro, Ligia P; David, Taynah I P; Bustos, Silvina O; Strauss, Bryan E; Gottifredi, Vanesa; Stary, Anne; Sarasin, Alain; Chammas, Roger; Menck, Carlos F M

2017-02-17

Genome lesions trigger biological responses that help cells manage damaged DNA, improving cell survival. Pol eta is a translesion synthesis (TLS) polymerase that bypasses lesions that block replicative polymerases, avoiding continued stalling of replication forks, which could lead to cell death. p53 also plays an important role in preventing cell death after ultraviolet (UV) light exposure. Intriguingly, we show that p53 does so by favoring translesion DNA synthesis by pol eta. In fact, the p53-dependent induction of pol eta in normal and DNA repair-deficient XP-C human cells after UV exposure has a protective effect on cell survival after challenging UV exposures, which was absent in p53- and Pol H-silenced cells. Viability increase was associated with improved elongation of nascent DNA, indicating the protective effect was due to more efficient lesion bypass by pol eta. This protection was observed in cells proficient or deficient in nucleotide excision repair, suggesting that, from a cell survival perspective, proper bypass of DNA damage can be as relevant as removal. These results indicate p53 controls the induction of pol eta in DNA damaged human cells, resulting in improved TLS and enhancing cell tolerance to DNA damage, which parallels SOS responses in bacteria. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Milk thistle seed extract protects rat C6 astroglial cells from acute cocaine toxicity.

PubMed

Badisa, Ramesh B; Fitch-Pye, Cheryl A; Agharahimi, Maryam; Palm, Donald E; Latinwo, Lekan M; Goodman, Carl B

2014-11-01

Cocaine is a powerful addictive drug, widely abused in most Western countries. It easily reaches various domains within and outside of the central nervous system (CNS), and triggers varying levels of cellular toxicity. No pharmacological treatment is available to alleviate cocaine-induced toxicity in the cells without side-effects. Here, we discerned the role of milk thistle (MT) seed extract against cocaine toxicity. First, we investigated acute cytotoxicity induced by treatment with 2, 3 and 4 mM cocaine for 1 h in astroglial, liver and kidney cells in vitro, and then in living shrimp larvae in vivo. We showed that astroglial cells are more sensitive to cocaine than liver, kidney cells or larvae. Cocaine exposure disrupted the general architecture of astroglial cells, induced vacuolation, decreased cell viability, and depleted the glutathione (GSH) level. These changes may represent the underlying pathology of cocaine in the astrocytes. By contrast, MT pretreatment (200 µg/ml) for 30 min sustained the cell morphological features and increased both cell viability and the GSH level. Besides its protective effects, the MT extract was revealed to be non-toxic to astroglial cells, and displayed high free-radical scavenging activity. The results from this study suggest that enhanced GSH level underlies cell protection, and indicate that compounds that promote GSH synthesis in the cells may be beneficial against cocaine toxicity.

Relative Contribution of Th1 and Th17 Cells in Adaptive Immunity to Bordetella pertussis: Towards the Rational Design of an Improved Acellular Pertussis Vaccine

PubMed Central

Ross, Pádraig J.; Allen, Aideen C.; Walsh, Kevin; Misiak, Alicja; Lavelle, Ed C.; McLoughlin, Rachel M.; Mills, Kingston H. G.

2013-01-01

Whooping cough caused by Bordetella pertussis is a re-emerging infectious disease despite the introduction of safer acellular pertussis vaccines (Pa). One explanation for this is that Pa are less protective than the more reactogenic whole cell pertussis vaccines (Pw) that they replaced. Although Pa induce potent antibody responses, and protection has been found to be associated with high concentrations of circulating IgG against vaccine antigens, it has not been firmly established that host protection induced with this vaccine is mediated solely by humoral immunity. The aim of this study was to examine the relative contribution of Th1 and Th17 cells in host immunity to infection with B. pertussis and in immunity induced by immunization with Pw and Pa and to use this information to help rationally design a more effective Pa. Our findings demonstrate that Th1 and Th17 both function in protective immunity induced by infection with B. pertussis or immunization with Pw. In contrast, a current licensed Pa, administered with alum as the adjuvant, induced Th2 and Th17 cells, but weak Th1 responses. We found that IL-1 signalling played a central role in protective immunity induced with alum-adsorbed Pa and this was associated with the induction of Th17 cells. Pa generated strong antibody and Th2 responses, but was fully protective in IL-4-defective mice, suggesting that Th2 cells were dispensable. In contrast, Pa failed to confer protective immunity in IL-17A-defective mice. Bacterial clearance mediated by Pa-induced Th17 cells was associated with cell recruitment to the lungs after challenge. Finally, protective immunity induced by an experimental Pa could be enhanced by substituting alum with a TLR agonist that induces Th1 cells. Our findings demonstrate that alum promotes protective immunity through IL-1β-induced IL-17A production, but also reveal that optimum protection against B. pertussis requires induction of Th1, but not Th2 cells. PMID:23592988

Protective effects of sweet orange (Citrus sinensis) peel and their bioactive compounds on oxidative stress.

PubMed

Chen, Zong-Tsi; Chu, Heuy-Ling; Chyau, Charng-Cherng; Chu, Chin-Chen; Duh, Pin-Der

2012-12-15

Protective effects of sweet orange (Citrus sinensis) peel and their bioactive compounds on oxidative stress were investigated. According to HPLC-DAD and HPLC-MS/MS analysis, hesperidin (HD), hesperetin (HT), nobiletin (NT), and tangeretin (TT) were present in water extracts of sweet orange peel (WESP). The cytotoxic effect in 0.2mM t-BHP-induced HepG2 cells was inhibited by WESP and their bioactive compounds. The protective effect of WESP and their bioactive compounds in 0.2mM t-BHP-induced HepG2 cells may be associated with positive regulation of GSH levels and antioxidant enzymes, decrease in ROS formation and TBARS generation, increase in the mitochondria membrane potential and Bcl-2/Bax ratio, as well as decrease in caspase-3 activation. Overall, WESP displayed a significant cytoprotective effect against oxidative stress, which may be most likely because of the phenolics-related bioactive compounds in WESP, leading to maintenance of the normal redox status of cells. Copyright © 2012 Elsevier Ltd. All rights reserved.

Melatonin partially protects 661W cells from H2O2-induced death by inhibiting Fas/FasL-caspase-3.

PubMed

Sánchez-Bretaño, Aída; Baba, Kenkichi; Janjua, Uzair; Piano, Ilaria; Gargini, Claudia; Tosini, Gianluca

2017-01-01

Previous studies have shown that melatonin (MEL) signaling is involved in the modulation of photoreceptor viability during aging. Recent work by our laboratory suggested that MEL may protect cones by modulating the Fas/FasL-caspase-3 pathway. In this study, we first investigated the presence of MEL receptors (MT 1 and MT 2 ) in 661W cells, then whether MEL can prevent H 2 O 2 -induced cell death, and last, through which pathway MEL confers protection. The mRNA and proteins of the MEL receptors were detected with quantitative PCR (q-PCR) and immunocytochemistry, respectively. To test the protective effect of MEL, 661W cells were treated with H 2 O 2 for 2 h in the presence or absence of MEL, a MEL agonist, and an antagonist. To study the pathways involved in H 2 O 2 -mediated cell death, a Fas/FasL antagonist was used before the exposure to H 2 O 2 . Finally, Fas/FasL and caspase-3 mRNA was analyzed with q-PCR and immunocytochemistry in cells treated with H 2 O 2 and/or MEL. Cell viability was analyzed by using Trypan Blue. Both MEL receptors (MT 1 and MT 2 ) were detected at the mRNA and protein levels in 661W cells. MEL partially prevented H 2 O 2 -mediated cell death (20-25%). This effect was replicated with IIK7 (a melatonin receptor agonist) when used at a concentration of 1 µM. Preincubation with luzindole (a melatonin receptor antagonist) blocked MEL protection. Kp7-6, an antagonist of Fas/FasL, blocked cell death caused by H 2 O 2 similarly to what was observed for MEL. Fas, FasL, and caspase-3 expression was increased in cells treated with H 2 O 2 , and this effect was prevented by MEL. Finally, MEL treatment partially prevented the activation of caspase-3 caused by H 2 O 2 . The results demonstrate that MEL receptors are present and functional in 661W cells. MEL can prevent photoreceptor cell death induced by H 2 O 2 via the inhibition of the proapoptotic pathway Fas/FasL-caspase-3.

Evaluation of the cytotoxic and antimutagenic effects of biflorin, an antitumor 1,4 o-naphthoquinone isolated from Capraria biflora L.

PubMed

Vasconcellos, Marne C; Moura, Dinara J; Rosa, Renato M; Machado, Miriana S; Guecheva, Temenouga N; Villela, Izabel; Immich, Bruna F; Montenegro, Raquel C; Fonseca, Aluísio M; Lemos, Telma L G; Moraes, Maria Elisabete A; Saffi, Jenifer; Costa-Lotufo, Letícia V; Moraes, Manoel O; Henriques, João A P

2010-10-01

Biflorin is a natural quinone isolated from Capraria biflora L. Previous studies demonstrated that biflorin inhibits in vitro and in vivo tumor cell growth and presents potent antioxidant activity. In this paper, we report concentration-dependent cytotoxic, genotoxic, antimutagenic, and protective effects of biflorin on Salmonella tiphymurium, yeast Saccharomyces cerevisiae, and V79 mammalian cells, using different approaches. In the Salmonella/microsome assay, biflorin was not mutagenic to TA97a TA98, TA100, and TA102 strains. However, biflorin was able to induce cytotoxicity in haploid S. cerevisiae cells in stationary and exponential phase growth. In diploid yeast cells, biflorin did not induce significant mutagenic and recombinogenic effects at the employed concentration range. In addition, the pre-treatment with biflorin prevented the mutagenic and recombinogenic events induced by hydrogen peroxide (H(2)O(2)) in S. cerevisiae. In V79 mammalian cells, biflorin was cytotoxic at higher concentrations. Moreover, at low concentrations biflorin pre-treatment protected against H(2)O(2)-induced oxidative damage by reducing lipid peroxidation and DNA damage as evaluated by normal and modified comet assay using DNA glycosylases. Our results suggest that biflorin cellular effects are concentration dependent. At lower concentrations, biflorin has significant antioxidant and protective effects against the cytotoxicity, genotoxicity, mutagenicity, and intracellular lipid peroxidation induced by H(2)O(2) in yeast and mammalian cells, which can be attributed to its hydroxyl radical-scavenging property. However, at higher concentrations, biflorin is cytotoxic and genotoxic.

Cerium oxide nanoparticles, combining antioxidant and UV shielding properties, prevent UV-induced cell damage and mutagenesis

NASA Astrophysics Data System (ADS)

Caputo, Fanny; de Nicola, Milena; Sienkiewicz, Andrzej; Giovanetti, Anna; Bejarano, Ignacio; Licoccia, Silvia; Traversa, Enrico; Ghibelli, Lina

2015-09-01

Efficient inorganic UV shields, mostly based on refracting TiO2 particles, have dramatically changed the sun exposure habits. Unfortunately, health concerns have emerged from the pro-oxidant photocatalytic effect of UV-irradiated TiO2, which mediates toxic effects on cells. Therefore, improvements in cosmetic solar shield technology are a strong priority. CeO2 nanoparticles are not only UV refractors but also potent biological antioxidants due to the surface 3+/4+ valency switch, which confers anti-inflammatory, anti-ageing and therapeutic properties. Herein, UV irradiation protocols were set up, allowing selective study of the extra-shielding effects of CeO2vs. TiO2 nanoparticles on reporter cells. TiO2 irradiated with UV (especially UVA) exerted strong photocatalytic effects, superimposing their pro-oxidant, cell-damaging and mutagenic action when induced by UV, thereby worsening the UV toxicity. On the contrary, irradiated CeO2 nanoparticles, via their Ce3+/Ce4+ redox couple, exerted impressive protection on UV-treated cells, by buffering oxidation, preserving viability and proliferation, reducing DNA damage and accelerating repair; strikingly, they almost eliminated mutagenesis, thus acting as an important tool to prevent skin cancer. Interestingly, CeO2 nanoparticles also protect cells from the damage induced by irradiated TiO2, suggesting that these two particles may also complement their effects in solar lotions. CeO2 nanoparticles, which intrinsically couple UV shielding with biological and genetic protection, appear to be ideal candidates for next-generation sun shields.

Protective effect of Schizandrin B against damage of UVB irradiated skin cells depend on inhibition of inflammatory pathways.

PubMed

Gao, Chenguang; Chen, Hong; Niu, Cong; Hu, Jie; Cao, Bo

2017-01-02

Schizandrin B is extracted from Schisandra chinensis (Turcz.) Baill. This study evaluated the photoprotective effect of Schizandrin B on oxidative stress injury of the skin caused by UVB-irradiation and the molecular mechanism of the photoprotective effect of Schizandrin B, and we firstly found that Schizandrin B could block Cox-2, IL-6 and IL-18 signal pathway to protect damage of skin cells given by UVB-irradiation. In the research, we found that Schizandrin B can attenuate the UVB-induced toxicity on keratinocytes and dermal fibroblasts in human body, and can outstandingly eliminated intracellular ROS produced by UVB-irradiation. These results demonstrate that Schizandrin B can regulate the function of decreasing intracellular SOD's activity and increasing the expression level of MDA in HaCaT cells result from the guidance of UVB, and it markedly reduced the production of inflammatory factors such as Cox-2, IL-6 or IL-18, decreased the expression level of MMP-1, and interdicted degradation process of collagens in UVB-radiated cells. Therefore, skin keratinocytes can be effectively protected from UVB-radiated damage by Schizandrin B, and UVB-irradiation caused inflammatory responses can be inhibited by attenuating process of ROS generating.

Pretreatment with apoaequorin protects hippocampal CA1 neurons from oxygen-glucose deprivation.

PubMed

Detert, Julia A; Adams, Erin L; Lescher, Jacob D; Lyons, Jeri-Anne; Moyer, James R

2013-01-01

Ischemic stroke affects ∼795,000 people each year in the U.S., which results in an estimated annual cost of $73.7 billion. Calcium is pivotal in a variety of neuronal signaling cascades, however, during ischemia, excess calcium influx can trigger excitotoxic cell death. Calcium binding proteins help neurons regulate/buffer intracellular calcium levels during ischemia. Aequorin is a calcium binding protein isolated from the jellyfish Aequorea victoria, and has been used for years as a calcium indicator, but little is known about its neuroprotective properties. The present study used an in vitro rat brain slice preparation to test the hypothesis that an intra-hippocampal infusion of apoaequorin (the calcium binding component of aequorin) protects neurons from ischemic cell death. Bilaterally cannulated rats received an apoaequorin infusion in one hemisphere and vehicle control in the other. Hippocampal slices were then prepared and subjected to 5 minutes of oxygen-glucose deprivation (OGD), and cell death was assayed by trypan blue exclusion. Apoaequorin dose-dependently protected neurons from OGD--doses of 1% and 4% (but not 0.4%) significantly decreased the number of trypan blue-labeled neurons. This effect was also time dependent, lasting up to 48 hours. This time dependent effect was paralleled by changes in cytokine and chemokine expression, indicating that apoaequorin may protect neurons via a neuroimmunomodulatory mechanism. These data support the hypothesis that pretreatment with apoaequorin protects neurons against ischemic cell death, and may be an effective neurotherapeutic.

Neuroprotective effects of metabotropic glutamate receptor group II and III activators against MPP(+)-induced cell death in human neuroblastoma SH-SY5Y cells: the impact of cell differentiation state.

PubMed

Jantas, D; Greda, A; Golda, S; Korostynski, M; Grygier, B; Roman, A; Pilc, A; Lason, W

2014-08-01

Recent studies have documented that metabotropic glutamate receptors from group II and III (mGluR II/III) are a potential target in the symptomatic treatment of Parkinson's disease (PD), however, the neuroprotective effects of particular mGluR II/III subtypes in relation to PD pathology are recognized only partially. In the present study, we investigated the effect of various mGluR II/III activators in the in vitro model of PD using human neuroblastoma SH-SY5Y cell line and mitochondrial neurotoxin MPP(+). We demonstrated that all tested mGluR ligands: mGluR II agonist - LY354740, mGluR III agonist - ACPT-I, mGluR4 PAM - VU0361737, mGluR8 agonist - (S)-3,4-DCPG, mGluR8 PAM - AZ12216052 and mGluR7 allosteric agonist - AMN082 were protective against MPP(+)-evoked cell damage in undifferentiated (UN-) SH-SY5Y cells with the highest neuroprotection mediated by mGluR8-specific agents. However, in retinoic acid- differentiated (RA-) SH-SY5Y cells we found protection mediated only by mGluR8 activators. We also demonstrated the cell proliferation stimulating effect for mGluR4 and mGluR8 PAMs. Next, we showed that the protection mediated by mGluR II/III activators in UN-SH-SY5Y was not accompanied by the modulation of caspase-3 activity, however, a decrease in the number of apoptotic nuclei was found. Finally, we showed that the inhibitor of necroptosis, necrostatin-1 blocked the mGluR III-mediated protection. Altogether our comparative in vitro data add a further proof to neuroprotective effects of mGluR agonists or PAMs and point to mGluR8 as a promising target for neuroprotective interventions in PD. The results also suggest the participation of necroptosis-related molecular pathways in neuroprotective effects of mGluR III activation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Influence of tumors on protective anti-tumor immunity and the effects of irradiation

PubMed Central

Foulds, Gemma A.; Radons, Jürgen; Kreuzer, Mira; Multhoff, Gabriele; Pockley, Alan G.

2012-01-01

Innate and adaptive immunity plays important roles in the development and progression of cancer and it is becoming apparent that tumors can influence the induction of potentially protective responses in a number of ways. The prevalence of immunoregulatory T cell populations in the circulation and tumors of patients with cancer is increased and the presence of these cells appears to present a major barrier to the induction of tumor immunity. One aspect of tumor-mediated immunoregulation which has received comparatively little attention is that which is directed toward natural killer (NK) cells, although evidence that the phenotype and function of NK cell populations are modified in patients with cancer is accumulating. Although the precise mechanisms underlying these localized and systemic immunoregulatory effects remain unclear, tumor-derived factors appear, in part at least, to be involved. The effects could be manifested by an altered function and/or via an influence on the migratory properties of individual cell subsets. A better insight into endogenous immunoregulatory mechanisms and the capacity of tumors to modify the phenotype and function of innate and adaptive immune cells might assist the development of new immunotherapeutic approaches and improve the management of patients with cancer. This article reviews current knowledge relating to the influence of tumors on protective anti-tumor immunity and considers the potential influence that radiation-induced effects might have on the prevalence, phenotype, and function of innate and adaptive immune cells in patients with cancer. PMID:23378947

Epigallocatechin gallate protects dopaminergic neurons against 1-methyl-4- phenyl-1,2,3,6-tetrahydropyridine-induced neurotoxicity by inhibiting microglial cell activation.

PubMed

Li, Rui; Peng, Ning; Du, Fang; Li, Xu-ping; Le, Wei-dong

2006-04-01

To observe whether the dopaminergic neuroprotective effect of (-)-epigallocatechin gallate (EGCG) is associated with its inhibition of microglial cell activation in vivo. The effects of EGCG at different doses on dopaminergic neuronal survival were tested in a methyl-4-phenyl-pyridinium (MPP+)-induced dopaminergic neuronal injury model in the primary mesencephalic cell cultures. With unbiased stereological method, tyrosine hydroxylase-immunoreactive (TH-ir) cells were counted in the A8, A9 and A10 regions of the substantia nigra (SN) in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated C57BL/6 mice. The effect of EGCG on microglial activation in the SN was also investigated. Pretreatment with EGCG (1 to 100 micromol/L) significantly attenuated MPP+-induced TH-ir cell loss by 22.2% to 80.5% in the mesencephalic cell cultures. In MPTP-treated C57BL/6 mice, EGCG at a low concentration (1 mg/kg) provided significant protection against MPTP-induced TH-ir cell loss by 50.9% in the whole nigral area and by 71.7% in the A9 region. EGCG at 5 mg/kg showed more prominent protective effect than at 1 or 10 mg/kg. EGCG pretreatment significantly inhibited microglial activation and CD11b expression induced by MPTP. EGCG exerts potent dopaminergic neuroprotective activity by means of microglial inhibition, which shed light on the potential use of EGCG in treatment of Parkinson's disease.

Gender difference in cytoprotection induced by estrogen on female and male bovine aortic endothelial cells.

PubMed

Si, M L; Al-Sharafi, B; Lai, C C; Khardori, R; Chang, C; Su, C Y

2001-08-01

Before menopause, women have a lower risk of cardiovascular diseases than men. Studies attribute this gender difference to estrogenic protection in the female cardiovascular system. We have demonstrated that 17beta-estradiol (E2) protects female bovine aortic endothelial cells against oxidative injury, probably through the induction of antioxidant enzyme activities. In this study, we examined whether E2 confers a differential protection on male and female cells. Bovine aortic endothelial cells from both genders were preconditioned for 24 h with E2 (1 nM to 10 microM), and their resistance to paraquat (1 mM, 3 h), a superoxide generator, was measured using an MTT assay. In contrast to the protection observed in female bovine aortic endothelial cells, there was no protective effect by E2 on male bovine aortic endothelial cells at physiologic concentrations. However, E2 at 1-10 microM attenuated paraquat's toxicity in both male and female cells, probably through its direct antioxidant activity. E2 at 1 nM increased in female, but not in male, cells the activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase, which was associated with decreased levels of reactive oxygen species during subsequent paraquat exposure. This suggests that antioxidant enzyme induction plays some role in E2-augmented oxidative resistance in female endothelial cells.

Mechanisms underlying the wound healing potential of propolis based on its in vitro antioxidant activity.

PubMed

Cao, Xue-Ping; Chen, Yi-Fan; Zhang, Jiang-Lin; You, Meng-Meng; Wang, Kai; Hu, Fu-Liang

2017-10-15

Propolis is a resinous substance collected by honeybees, Apis mellifera, from various plant sources. Having various pharmacological and biological activities, it has been used in folk medicine and complementary therapies since ancient times. To evaluate the effects and underlying mechanism of the protective effects of the ethanol extract of Chinese propolis (EECP) on L929 cells injured by hydrogen peroxide (H 2 O 2 ). The wound healing activities of EECP in L929 cells with H 2 O 2 -induced damage were investigated. The main components of EECP were analyzed by RP-HPLC, and the free radical scavenging capacity and reducing power were also measured. The effects of EECP on the expression of antioxidant-related genes in fibroblast L929 cells were determined using qRT-PCR and western blotting. EECP had significant protective effects against cell death induced by H 2 O 2 and significantly inhibited the decline of collagen mRNA expression caused by H 2 O 2 in L929 cells. EECP induced the expression of antioxidant-related genes, such as HO-1, GCLM, and GCLC, which has great implications for the potential of propolis to alleviate oxidative stress in wound tissues. The protective effects of propolis have great implications for using propolis as a wound healing regent. Copyright © 2017 Elsevier GmbH. All rights reserved.

Histone Deacetylase Inhibitors Target the Leukemic Microenvironment by Enhancing a Nherf1-Protein Phosphatase 1α-TAZ Signaling Pathway in Osteoblasts*

PubMed Central

Kremer, Kimberly N.; Dudakovic, Amel; Hess, Allan D.; Smith, B. Douglas; Karp, Judith E.; Kaufmann, Scott H.; Westendorf, Jennifer J.; van Wijnen, Andre J.; Hedin, Karen E.

2015-01-01

Disrupting the protective signals provided by the bone marrow microenvironment will be critical for more effective combination drug therapies for acute myeloid leukemia (AML). Cells of the osteoblast lineage that reside in the endosteal niche have been implicated in promoting survival of AML cells. Here, we investigated how to prevent this protective interaction. We previously showed that SDF-1, a chemokine abundant in the bone marrow, induces apoptosis of AML cells, unless the leukemic cells receive protective signals provided by differentiating osteoblasts (8, 10). We now identify a novel signaling pathway in differentiating osteoblasts that can be manipulated to disrupt the osteoblast-mediated protection of AML cells. Treating differentiating osteoblasts with histone deacetylase inhibitors (HDACi) abrogated their ability to protect co-cultured AML cells from SDF-1-induced apoptosis. HDACi prominently up-regulated expression of the Nherf1 scaffold protein, which played a major role in preventing osteoblast-mediated protection of AML cells. Protein phosphatase-1α (PP1α) was identified as a novel Nherf1 interacting protein that acts as the downstream mediator of this response by promoting nuclear localization of the TAZ transcriptional modulator. Moreover, independent activation of either PP1α or TAZ was sufficient to prevent osteoblast-mediated protection of AML cells even in the absence of HDACi. Together, these results indicate that HDACi target the AML microenvironment by enhancing activation of the Nherf1-PP1α-TAZ pathway in osteoblasts. Selective drug targeting of this osteoblast signaling pathway may improve treatments of AML by rendering leukemic cells in the bone marrow more susceptible to apoptosis. PMID:26491017

Ebselen reduces the toxicity of mechlorethamine in A-431 cells via inhibition of apoptosis.

PubMed

Lulla, Anju; Pino, Maria A; Piętka-Ottlik, Magdalena; Młochowski, Jacek; Sparavalo, Oleksiy; Billack, Blase

2013-06-01

A series of test compounds were evaluated for an ability to reduce the toxicity of the nitrogen mustard mechlorethamine (HN2) in vitro. The test compounds included resveratrol, pterostilbene, vitamin C, ebselen, ebselen diselenide, and ebselen-sulfur. Among them, ebselen demonstrated the highest degree of protection against HN2 toxicity. To this end, pretreatment of the cells with ebselen offered protection against the toxicant whereas no protection was observed when cells were first incubated with HN2 and then treated with ebselen. Significant increases in caspase 3 and caspase 9 activities were observed in response to HN2, and ebselen was found to reduce these effects. Taken together, the data presented here indicate that ebselen is an effective countermeasure to nitrogen mustard in vitro, which is worthy of future investigation in vivo. © 2013 Wiley Periodicals, Inc.

Protective effect of vanilloids against tert-butyl hydroperoxide-induced oxidative stress in vero cells culture.

PubMed

Rosa, Antonella; Atzeri, Angela; Deiana, Monica; Melis, M Paola; Incani, Alessandra; Corona, Giulia; Loru, Debora; Appendino, Giovanni; Dessì, M Assunta

2008-05-28

This study investigated the effect of synthetic capsiate, a simplified analogue of capsiate, and vanillyl alcohol on the oxidative stress induced by tert-butyl hydroperoxide (TBH) in a line of fibroblasts derived from monkey kidney (Vero cells). In response to the TBH-mediated oxidative stress, a reduction of the levels of total unsaturated fatty acids and cholesterol was observed, and a rise in the concentrations of conjugated dienes fatty acids hydroperoxides and 7-ketocholesterol. Pretreatment with both synthetic capsiate and vanillyl alcohol preserved Vero cells from oxidative damage and showed a remarkable protective effect on the reduction of the levels of total unsaturated fatty acids and cholesterol, inhibiting the increase of MDA, conjugated dienes fatty acids hydroperoxides, and 7-ketocholesterol. Both compounds were effective against peroxidation of cell membrane lipids induced by TBH, with synthetic capsiate essentially acting as a pro-drug of vanillyl alcohol, its hydrophilic hydrolytic derivative.

Estrogen, aging and the cardiovascular system

PubMed Central

Stice, James P.; Lee, Jennifer S.; Pechenino, Angela S.; Knowlton, Anne A.

2014-01-01

Estrogen is a powerful hormone with pleiotropic effects. Estrogens have potent antioxidant effects and are able to reduce inflammation, induce vasorelaxation and alter gene expression in both the vasculature and the heart. Estrogen treatment of cultured cardiac myocytes and endothelial cells rapidly activates NFκB, induces heat-shock protein (HSP)-72, a potent intracellular protective protein, and protects cells from simulated ischemia. In in vivo models, estrogens protect against ischemia and trauma/hemorrhage. Estrogens may decrease the expression of soluble epoxide hydrolase, which has deleterious effects on the cardiovascular system through metabolism of epoxyeicosatrienoic acids. Natural (endogenous) estrogens in premenopausal women appear to protect against cardiovascular disease and yet controlled clinical trials have not indicated a benefit from estrogen replacement postmenopause. Much remains to be understood in regards to the many properties of this powerful hormone and how changes in this hormone interact with aging-associated changes. The unexpected negative results of trials of estrogen replacement postmenopause probably arise from our lack of understanding of the many effects of this hormone. PMID:19371207

Biochemical and immunological mechanisms by which sickle cell trait protects against malaria.

PubMed

Gong, Lauren; Parikh, Sunil; Rosenthal, Philip J; Greenhouse, Bryan

2013-09-11

Sickle cell trait (HbAS) is the best-characterized genetic polymorphism known to protect against falciparum malaria. Although the protective effect of HbAS against malaria is well known, the mechanism(s) of protection remain unclear. A number of biochemical and immune-mediated mechanisms have been proposed, and it is likely that multiple complex mechanisms are responsible for the observed protection. Increased evidence for an immune component of protection as well as novel mechanisms, such as enhanced tolerance to disease mediated by HO-1 and reduced parasitic growth due to translocation of host micro-RNA into the parasite, have recently been described. A better understanding of relevant mechanisms will provide valuable insight into the host-parasite relationship, including the role of the host immune system in protection against malaria.

Biochemical and immunological mechanisms by which sickle cell trait protects against malaria

PubMed Central

2013-01-01

Sickle cell trait (HbAS) is the best-characterized genetic polymorphism known to protect against falciparum malaria. Although the protective effect of HbAS against malaria is well known, the mechanism(s) of protection remain unclear. A number of biochemical and immune-mediated mechanisms have been proposed, and it is likely that multiple complex mechanisms are responsible for the observed protection. Increased evidence for an immune component of protection as well as novel mechanisms, such as enhanced tolerance to disease mediated by HO-1 and reduced parasitic growth due to translocation of host micro-RNA into the parasite, have recently been described. A better understanding of relevant mechanisms will provide valuable insight into the host-parasite relationship, including the role of the host immune system in protection against malaria. PMID:24025776

Assessment of antioxidative, chelating, and DNA-protective effects of selected essential oil components (eugenol, carvacrol, thymol, borneol, eucalyptol) of plants and intact Rosmarinus officinalis oil.

PubMed

Horvathova, Eva; Navarova, Jana; Galova, Eliska; Sevcovicova, Andrea; Chodakova, Lenka; Snahnicanova, Zuzana; Melusova, Martina; Kozics, Katarina; Slamenova, Darina

2014-07-16

Selected components of plant essential oils and intact Rosmarinus officinalis oil (RO) were investigated for their antioxidant, iron-chelating, and DNA-protective effects. Antioxidant activities were assessed using four different techniques. DNA-protective effects on human hepatoma HepG2 cells and plasmid DNA were evaluated with the help of the comet assay and the DNA topology test, respectively. It was observed that whereas eugenol, carvacrol, and thymol showed high antioxidative effectiveness in all assays used, RO manifested only antiradical effect and borneol and eucalyptol did not express antioxidant activity at all. DNA-protective ability against hydrogen peroxide (H2O2)-induced DNA lesions was manifested by two antioxidants (carvacrol and thymol) and two compounds that do not show antioxidant effects (RO and borneol). Borneol was able to preserve not only DNA of HepG2 cells but also plasmid DNA against Fe(2+)-induced damage. This paper evaluates the results in the light of experiences of other scientists.

Orexin-A Protects Human Neuroblastoma SH-SY5Y Cells Against 6-Hydroxydopamine-Induced Neurotoxicity: Involvement of PKC and PI3K Signaling Pathways.

PubMed

Pasban-Aliabadi, Hamzeh; Esmaeili-Mahani, Saeed; Abbasnejad, Mehdi

2017-04-01

Parkinson's disease (PD) is a common neurodegenerative disorder that is characterized by progressive and selective death of dopaminergic neurons. Multifunctional neuropeptide orexin-A is involved in many biological events of the body. It has been shown that orexin-A has protective effects in neurodegenerative disease such as PD. However, its cellular mechanisms have not yet been fully clarified. Here, we investigated the intracellular signaling pathway of orexin-A neuroprotection in 6-hydroxydopamine (6-OHDA)-induced SH-SY5H cells damage as an in vitro model of PD. The cells were incubated with 150 μM 6-OHDA, and the viability was examined by 3-[4,5-dimethyl-2-thiazolyl]-2,5-diphenyl-2-tetrazolium bromide (MTT) assay. Mitochondrial membrane potential and intracellular calcium were measured by fluorescent probes. Western blotting was also used to determine cyclooxygenase type 2 (COX-2), nuclear factor erythroid 2 related factor 2 (Nrf2), and HSP70 protein levels. The data showed that 6-OHDA has decreasing effects on cell viability, Nrf2, and HSP70 protein expression and increases the level of mitochondrial membrane potential, intracellular calcium, and COX-2 protein. Orexin-A (500 pM) significantly attenuated the 6-OHDA-induced cell damage. Furthermore, Orexin-A significantly prevented the mentioned effects of 6-OHDA on SH-SY5Y cells. Orexin 1 receptor antagonist (SB3344867), PKC, and PI3-kinase (PI3K) inhibitors (chelerythrin and LY294002, respectively) could suppress the orexin-A neuroprotective effect. In contrast, blockage of PKA by a selective inhibitor (KT5720) had no effects on the orexin protection. The results suggest that orexin-A protective effects against 6-OHDA-induced neurotoxicity are performed via its receptors, PKC and PI3K signaling pathways.

Δ⁹-tetrahydrocannabinol (Δ⁹-THC) exerts a direct neuroprotective effect in a human cell culture model of Parkinson's disease.

PubMed

Carroll, C B; Zeissler, M-L; Hanemann, C O; Zajicek, J P

2012-10-01

Δ⁹-tetrahydrocannabinol (Δ⁹-THC) is neuroprotective in models of Parkinson's disease (PD). Although CB1 receptors are increased within the basal ganglia of PD patients and animal models, current evidence suggests a role for CB1 receptor-independent mechanisms. Here, we utilized a human neuronal cell culture PD model to further investigate the protective properties of Δ⁹-THC. Differentiated SH-SY5Y neuroblastoma cells were exposed to PD-relevant toxins: 1-methyl-4-phenylpyridinium (MPP+), lactacystin and paraquat. Changes in CB1 receptor level were determined by quantitative polymerase chain reaction and Western blotting. Cannabinoids and modulatory compounds were co-administered with toxins for 48 h and the effects on cell death, viability, apoptosis and oxidative stress assessed. We found CB1 receptor up-regulation in response to MPP+, lactacystin and paraquat and a protective effect of Δ⁹-THC against all three toxins. This neuroprotective effect was not reproduced by the CB1 receptor agonist WIN55,212-2 or blocked by the CB1 antagonist AM251. Furthermore, the antioxidants α-tocopherol and butylhydroxytoluene as well as the antioxidant cannabinoids, nabilone and cannabidiol were unable to elicit the same neuroprotection as Δ⁹-THC. However, the peroxisome proliferator-activated receptor-gamma (PPARγ) antagonist T0070907 dose-dependently blocked the neuroprotective, antioxidant and anti-apoptotic effects of Δ⁹-THC, while the PPARγ agonist pioglitazone resulted in protection from MPP+-induced neurotoxicity. Furthermore, Δ⁹-THC increased PPARγ expression in MPP+-treated SH-SY5Y cells, another indicator of PPARγ activation. We have demonstrated up-regulation of the CB1 receptor in direct response to neuronal injury in a human PD cell culture model, and a direct neuronal protective effect of Δ⁹-THC that may be mediated through PPARγ activation. © 2011 The Authors. Neuropathology and Applied Neurobiology © 2011 British Neuropathological Society.

Ammonia impairs glutamatergic communication in astroglial cells: protective role of resveratrol.

PubMed

Bobermin, Larissa Daniele; Hansel, Gisele; Scherer, Emilene B S; Wyse, Angela T S; Souza, Diogo Onofre; Quincozes-Santos, André; Gonçalves, Carlos-Alberto

2015-12-01

Ammonia is a key toxin in the precipitation of hepatic encephalopathy (HE), a neuropsychiatric disorder associated with liver failure. In response to ammonia, various toxic events are triggered in astroglial cells, and alterations in brain glutamate communication are common. Resveratrol is a polyphenolic compound that has been extensively studied in pathological events because it presents several beneficial effects, including some in the central nervous system (CNS). We previously described that resveratrol is able to significantly modulate glial functioning and has a protective effect during ammonia challenge in vitro. In this study, we addressed the mechanisms by which resveratrol can protect C6 astroglial cells from glutamatergic alterations induced by ammonia. Resveratrol was able to prevent all the effects triggered by ammonia: (i) decrease in glutamate uptake activity and expression of the EAAC1 glutamate transporter, the main glutamate transporter present in C6 cells; (ii) increase of glutamate release, which was also dependent on the activation of the Na(+)-K(+)-Cl(-) co-transporter NKCC1; (iii) reduction in GS activity and intracellular GSH content; and (iv) impairment of Na(+)K(+)-ATPase activity. Interestingly, resveratrol, per se, also positively modulated the astroglial functions evaluated. Moreover, we demonstrated that heme oxygenase 1 (HO1), an enzyme that is part of the cellular defense system, mediated some of the effects of resveratrol. In conclusion, the mechanisms of the putative protective role of resveratrol against ammonia toxicity involve the modulation of pathways and molecules related to glutamate communication in astroglial cells. Copyright © 2015 Elsevier B.V. All rights reserved.

Fructose and tagatose protect against oxidative cell injury by iron chelation.

PubMed

Valeri, F; Boess, F; Wolf, A; Göldlin, C; Boelsterli, U A

1997-01-01

To further investigate the mechanism by which fructose affords protection against oxidative cell injury, cultured rat hepatocytes were exposed to cocaine (300 microM) or nitrofurantoin (400 microM). Both drugs elicited massively increased lactate dehydrogenase release. The addition of the ketohexoses D-fructose (metabolized via glycolysis) or D-tagatose (poor glycolytic substrate) significantly attenuated cocaine- and nitrofurantoin-induced cell injury, although both fructose and tagatose caused a rapid depletion of ATP and compromised the cellular energy charge. Furthermore, fructose, tagatose, and sorbose all inhibited in a concentration-dependent manner (0-16 mM) luminolenhanced chemiluminescence (CL) in cell homogenates, indicating that these compounds inhibit the iron-dependent reactive oxygen species (ROS)-mediated peroxidation of luminol. Indeed, both Fe2+ and Fe3+ further increased cocaine-stimulated CL, which was markedly quenched following addition of the ketohexoses. The iron-independent formation of superoxide anion radicals (acetylated cytochrome c reduction) induced by the prooxidant drugs remained unaffected by fructose or tagatose. The iron-chelator deferoxamine similarly protected against prooxidant-induced cell injury. In contrast, the nonchelating aldohexoses D-glucose and D-galactose did not inhibit luminol CL nor did they protect against oxidative cell injury. These data indicate that ketohexoses can effectively protect against prooxidant-induced cell injury, independent of their glycolytic metabolism, by suppressing the iron-catalyzed formation of ROS.

The Flaxseed-Derived Lignan Phenolic Secoisolariciresinol Diglucoside (SDG) Protects Non-Malignant Lung Cells from Radiation Damage

PubMed Central

Velalopoulou, Anastasia; Tyagi, Sonia; Pietrofesa, Ralph A.; Arguiri, Evguenia; Christofidou-Solomidou, Melpo

2015-01-01

Plant phenolic compounds are common dietary antioxidants that possess antioxidant and anti-inflammatory properties. Flaxseed (FS) has been reported to be radioprotective in murine models of oxidative lung damage. Flaxseed’s protective properties are attributed to its main biphenolic lignan, secoisolariciresinol diglucoside (SDG). SDG is a free radical scavenger, shown in cell free systems to protect DNA from radiation-induced damage. The objective of this study was to investigate the in vitro radioprotective efficacy of SDG in murine lung cells. Protection against irradiation (IR)-induced DNA double and single strand breaks was assessed by γ-H2AX labeling and alkaline comet assay, respectively. The role of SDG in modulating the levels of cytoprotective enzymes was evaluated by qPCR and confirmed by Western blotting. Additionally, effects of SDG on clonogenic survival of irradiated cells were evaluated. SDG protected cells from IR-induced death and ameliorated DNA damage by reducing mean comet tail length and percentage of γ-H2AX positive cells. Importantly, SDG significantly increased gene and protein levels of antioxidant HO-1, GSTM1 and NQO1. Our results identify the potent radioprotective properties of the synthetic biphenolic SDG, preventing DNA damage and enhancing the antioxidant capacity of normal lung cells; thus, rendering SDG a potential radioprotector against radiation exposure. PMID:26703588

The Flaxseed-Derived Lignan Phenolic Secoisolariciresinol Diglucoside (SDG) Protects Non-Malignant Lung Cells from Radiation Damage.

PubMed

Velalopoulou, Anastasia; Tyagi, Sonia; Pietrofesa, Ralph A; Arguiri, Evguenia; Christofidou-Solomidou, Melpo

2015-12-22

Plant phenolic compounds are common dietary antioxidants that possess antioxidant and anti-inflammatory properties. Flaxseed (FS) has been reported to be radioprotective in murine models of oxidative lung damage. Flaxseed's protective properties are attributed to its main biphenolic lignan, secoisolariciresinol diglucoside (SDG). SDG is a free radical scavenger, shown in cell free systems to protect DNA from radiation-induced damage. The objective of this study was to investigate the in vitro radioprotective efficacy of SDG in murine lung cells. Protection against irradiation (IR)-induced DNA double and single strand breaks was assessed by γ-H2AX labeling and alkaline comet assay, respectively. The role of SDG in modulating the levels of cytoprotective enzymes was evaluated by qPCR and confirmed by Western blotting. Additionally, effects of SDG on clonogenic survival of irradiated cells were evaluated. SDG protected cells from IR-induced death and ameliorated DNA damage by reducing mean comet tail length and percentage of γ-H2AX positive cells. Importantly, SDG significantly increased gene and protein levels of antioxidant HO-1, GSTM1 and NQO1. Our results identify the potent radioprotective properties of the synthetic biphenolic SDG, preventing DNA damage and enhancing the antioxidant capacity of normal lung cells; thus, rendering SDG a potential radioprotector against radiation exposure.

Curcumin analog 1, 5-bis (2-trifluoromethylphenyl)-1, 4-pentadien-3-one exhibits enhanced ability on Nrf2 activation and protection against acrolein-induced ARPE-19 cell toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Yuan; Zou, Xuan; Cao, Ke

2013-11-01

Curcumin, a phytochemical agent in the spice turmeric, has received increasing attention for its anticancer, anti-inflammatory and antioxidant properties. However, application of curcumin has been limited due to its insolubility in water and poor bioavailability both clinically and experimentally. In addition, the protective effects and mechanisms of curcumin in eye diseases have been poorly studied. In the present study, we synthesized a curcumin analog, 1, 5-bis (2-trifluoromethylphenyl)-1, 4-pentadien-3-one (C3), which displayed improved protective effect against acrolein-induced toxicity in a human retinal pigment epithelial cell line (ARPE-19). At 5 μM, curcumin completely protected against acrolein-induced cell oxidative damage and preserved GSHmore » levels and mitochondrial function. Surprisingly, C3 displayed a complete protective effect at 0.5 μM, which was much more efficient than curcumin. Both 0.5 μM C3 and 5 μM curcumin induced Nrf2 nuclear translocation and Nrf2 target genes transcription similarly. Experiments using Nrf2 siRNA showed that the protective effects of curcumin and C3 were eliminated by Nrf2 knockdown. Additionally, both curcumin and C3 activated the PI3/Akt pathway, however, Nrf2 activation was independent of this pathway, and therefore, we hypothesized that both curcumin and C3 activated phase II enzymes via directly disrupting the Nrf2/Keap1 complex and promoting Nrf2's nuclear translocation. Since acrolein challenge of ARPE-19 cells has been used as a model of smoking and age-related macular degeneration (AMD), we concluded that the curcumin analog, C3, may be a more promising drug candidate for its potential application for the prevention and treatment of eye diseases, such as AMD. - Highlights: • We examine toxicity effects of cigarette smoking component acrolein in retina cells. • We report a more efficient curcumin analog (C3) protecting cellular function. • Mitochondrial function and phase II enzyme activation are the major targets of C3. • C3 is ten-fold more potent than curcumin on activating Nrf2 nuclear translocation. • Nrf2 translocation and Phase II enzyme induction are independent of PI3K/Akt pathway.« less

Protection of cultured brain endothelial cells from cytokine-induced damage by α-melanocyte stimulating hormone.

PubMed

Harazin, András; Bocsik, Alexandra; Barna, Lilla; Kincses, András; Váradi, Judit; Fenyvesi, Ferenc; Tubak, Vilmos; Deli, Maria A; Vecsernyés, Miklós

2018-01-01

The blood-brain barrier (BBB), an interface between the systemic circulation and the nervous system, can be a target of cytokines in inflammatory conditions. Pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) induce damage in brain endothelial cells and BBB dysfunction which contribute to neuronal injury. The neuroprotective effects of α-melanocyte stimulating hormone (α-MSH) were investigated in experimental models, but there are no data related to the BBB. Based on our recent study, in which α-MSH reduced barrier dysfunction in human intestinal epithelial cells induced by TNF-α and IL-1β, we hypothesized a protective effect of α-MSH on brain endothelial cells. We examined the effect of these two pro-inflammatory cytokines, and the neuropeptide α-MSH on a culture model of the BBB, primary rat brain endothelial cells co-cultured with rat brain pericytes and glial cells. We demonstrated the expression of melanocortin-1 receptor in isolated rat brain microvessels and cultured brain endothelial cells by RT-PCR and immunohistochemistry. TNF-α and IL-1β induced cell damage, measured by impedance and MTT assay, which was attenuated by α-MSH (1 and 10 pM). The peptide inhibited the cytokine-induced increase in brain endothelial permeability, and restored the morphological changes in cellular junctions visualized by immunostaining for claudin-5 and β-catenin. Elevated production of reactive oxygen species and the nuclear translocation of NF-κB were also reduced by α-MSH in brain endothelial cells stimulated by cytokines. We demonstrated for the first time the direct beneficial effect of α-MSH on cultured brain endothelial cells, indicating that this neurohormone may be protective at the BBB.

Protective Effects of Fisetin Against 6-OHDA-Induced Apoptosis by Activation of PI3K-Akt Signaling in Human Neuroblastoma SH-SY5Y Cells.

PubMed

Watanabe, Ryoko; Kurose, Takumi; Morishige, Yuta; Fujimori, Ko

2018-02-01

6-Hydroxydopamine (6-OHDA) induces the production of reactive oxygen species (ROS) that are associated with various neurodegenerative diseases such as Parkinson's disease. 3,3',4',7-Tetrahydroxyflavone (fisetin), a plant flavonoid has a variety of physiological effects such as antioxidant activity. In this study, we investigated the molecular mechanism of the neuroprotective effects of fisetin against 6-OHDA-induced cell death in human neuroblastoma SH-SY5Y cells. 6-OHDA-mediated cell toxicity was reduced in a fisetin concentration-dependent manner. 6-OHDA-mediated elevation of the expression of the oxidative stress-related genes such as hemeoxygenase-1, NAD(P)H dehydrogenase quinone 1, NF-E2-related factor 2, and γ-glutamate-cysteine ligase modifier was suppressed by fisetin. Fisetin also lowered the ratio of the proapoptotic Bax protein and the antiapoptotic Bcl-2 protein in SH-SY5Y cells. Moreover, fisetin effectively suppressed 6-OHDA-mediated activation of caspase-3 and caspase-9, which leads to the cell death, while, 6-OHDA-induced caspase-3/7 activity was lowered. Furthermore, fisetin activated the PI3K-Akt signaling, which inhibits the caspase cascade, and fisetin-mediated inhibition of 6-OHDA-induced cell death was negated by the co-treatment with an Akt inhibitor. These results indicate that fisetin protects 6-OHDA-induced cell death by activating PI3K-Akt signaling in human neuronal SH-SY5Y cells. This is the first report that the PI3K-Akt signaling is involved in the fisetin-protected ROS-mediated neuronal cell death.

Protection of cultured brain endothelial cells from cytokine-induced damage by α-melanocyte stimulating hormone

PubMed Central

Barna, Lilla; Kincses, András; Váradi, Judit; Fenyvesi, Ferenc; Tubak, Vilmos

2018-01-01

The blood–brain barrier (BBB), an interface between the systemic circulation and the nervous system, can be a target of cytokines in inflammatory conditions. Pro-inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) induce damage in brain endothelial cells and BBB dysfunction which contribute to neuronal injury. The neuroprotective effects of α-melanocyte stimulating hormone (α-MSH) were investigated in experimental models, but there are no data related to the BBB. Based on our recent study, in which α-MSH reduced barrier dysfunction in human intestinal epithelial cells induced by TNF-α and IL-1β, we hypothesized a protective effect of α-MSH on brain endothelial cells. We examined the effect of these two pro-inflammatory cytokines, and the neuropeptide α-MSH on a culture model of the BBB, primary rat brain endothelial cells co-cultured with rat brain pericytes and glial cells. We demonstrated the expression of melanocortin-1 receptor in isolated rat brain microvessels and cultured brain endothelial cells by RT-PCR and immunohistochemistry. TNF-α and IL-1β induced cell damage, measured by impedance and MTT assay, which was attenuated by α-MSH (1 and 10 pM). The peptide inhibited the cytokine-induced increase in brain endothelial permeability, and restored the morphological changes in cellular junctions visualized by immunostaining for claudin-5 and β-catenin. Elevated production of reactive oxygen species and the nuclear translocation of NF-κB were also reduced by α-MSH in brain endothelial cells stimulated by cytokines. We demonstrated for the first time the direct beneficial effect of α-MSH on cultured brain endothelial cells, indicating that this neurohormone may be protective at the BBB. PMID:29780671

Hydrogen protects against hyperoxia-induced apoptosis in type II alveolar epithelial cells via activation of PI3K/Akt/Foxo3a signaling pathway.

PubMed

Wu, Dan; Liang, Mulin; Dang, Hongxing; Fang, Fang; Xu, Feng; Liu, Chengjun

2018-01-08

Oxidative stress is regarded as a key regulator in the pathogenesis of prolonged hyperoxia-induced lung injury, which causes injury to alveolar epithelial cells and eventually leads to development of bronchopulmonary dysplasia (BPD). Many studies have shown that hydrogen has a protective effect in a variety of cells. However, the mechanisms by which hydrogen rescues cells from damage due to oxidative stress in BPD remains to be fully elucidated. This study sought to evaluate the effects of hydrogen on hyperoxia-induced lung injury and to investigate the underlying mechanism. Primary type II alveolar epithelial cells (AECIIs) were divided into four groups: control (21% oxygen), hyperoxia (95% oxygen), hyperoxia + hydrogen, and hyperoxia + hydrogen + LY294002 (a PI3K/Akt inhibitor). Proliferation and apoptosis of AECIIs were assessed using MTS assay and flow cytometry (FCM), respectively. Gene and protein expression were detected by quantitative polymerase chain reaction (q-PCR) and western blot analysis. Stimulation with hyperoxia decreased the expression of P-Akt, P- FoxO3a, cyclinD1 and Bcl-2. Hyperoxic conditions increased levels of Bim, Bax, and Foxo3a, which induced proliferation restriction and apoptosis of AECIIs. These effects of hyperoxia were reversed with hydrogen pretreatment. Furthermore, the protective effects of hydrogen were abrogated by PI3K/Akt inhibitor LY294002. The results indicate that hydrogen protects AECIIs from hyperoxia-induced apoptosis by inhibiting apoptosis factors and promoting the expression of anti-apoptosis factors. These effects were associated with activation of the PI3K/Akt/FoxO3a pathway. Copyright © 2017 Elsevier Inc. All rights reserved.

Protective effect of boric acid on lead- and cadmium-induced genotoxicity in V79 cells.

PubMed

Ustündağ, Aylin; Behm, Claudia; Föllmann, Wolfram; Duydu, Yalçin; Degen, Gisela H

2014-06-01

The toxic heavy metals cadmium (Cd) and lead (Pb) are important environmental pollutants which can cause serious damage to human health. As the metal ions (Cd(2+) and Pb(2+)) accumulate in the organism, there is special concern regarding chronic toxicity and damage to the genetic material. Metal-induced genotoxicity has been attributed to indirect mechanisms, such as induction of oxidative stress and interference with DNA repair. Boron is a naturally occurring element and considered to be an essential micronutrient, although the cellular activities of boron compounds remain largely unexplored. The present study has been conducted to evaluate potential protective effects of boric acid (BA) against genotoxicity induced by cadmium chloride (CdCl2) and lead chloride (PbCl2) in V79 cell cultures. Cytotoxicity assays (neutral red uptake and cell titer blue assay) served to determine suitable concentrations for subsequent genotoxicity assays. Chromosomal damage and DNA strand breaks were assessed by micronucleus tests and comet assays. Both PbCl2 and CdCl2 (at 3, 5 and 10 µM) were shown to induce concentration-dependent increases in micronucleus frequencies and DNA strand breaks in V79 cells. BA itself was not cytotoxic (up to 300 µM) and showed no genotoxic effects. Pretreatment of cells with low levels of BA (2.5 and 10 µM) was found to strongly reduce the genotoxic effects of the tested metals. Based on the findings of this in vitro study, it can be suggested that boron provides an efficient protection against the induction of DNA strand breaks and micronuclei by lead and cadmium. Further studies on the underlying mechanisms for the protective effect of boron are needed.

Protection of MES23.5 dopaminergic cells by obestatin is mediated by proliferative rather than anti-apoptotic action.

PubMed

Shen, Xiao-Li; Jia, Feng-Ju; Song, Ning; Xie, Jun-Xia; Jiang, Hong

2014-02-01

Obestatin is an endogenous peptide sharing a precursor with ghrelin. This study aims to investigate whether and how obestatin protects MES23.5 dopaminergic cells against 1-methyl-4-phenylpyridinium (MPP(+))-induced neurotoxicity. MES23.5 cells were pretreated with obestatin (10(-13)-10(-6) mol/L) for 20 min prior to incubation with 200 μmol/L MPP(+) for 12 or 24 h, or treated with obestatin alone (10(-13) to 10(-6) mol/L) for 0, 6, 12, and 24 h. The methyl thiazolyl tetrazolium (MTT) assay was used to measure cell viability. Flow cytometry was used to measure the caspase-3 activity and the mitochondrial transmembrane potential. Proliferating cell nuclear antigen (PCNA) protein levels were determined by Western blotting. Obestatin (10(-13) to 10(-7) mol/L) pretreatment blocked or even reversed the MPP(+)-induced reduction of viability in MES23.5 cells, but had no effect on MPP(+)-induced mitochondrial transmembrane potential collapse and caspase-3 activation. When applied alone, obestatin increased viability. Elevated PCNA levels occurred with 10(-7), 10(-9), 10(-11) and 10(-13) mol/L obestatin treatment for 12 h. The results suggest that the protective effects of obestatin against MPP(+) in MES23.5 cells are due to its proliferation-promoting rather than anti-apoptotic effects.

Eckol protects V79-4 lung fibroblast cells against gamma-ray radiation-induced apoptosis via the scavenging of reactive oxygen species and inhibiting of the c-Jun NH(2)-terminal kinase pathway.

PubMed

Zhang, Rui; Kang, Kyoung Ah; Piao, Mei Jing; Ko, Dong Ok; Wang, Zhi Hong; Lee, In Kyung; Kim, Bum Joon; Jeong, Il Yun; Shin, Taekyun; Park, Jae Woo; Lee, Nam Ho; Hyun, Jin Won

2008-09-04

The radioprotective effect of eckol against gamma-ray radiation-induced oxidative stress and its possible protective mechanisms were investigated. Eckol was found to reduce the intracellular reactive oxygen species generated by gamma-ray radiation. Moreover, eckol also protected against radiation-induced cellular DNA damage and membrane lipid peroxidation, which are the main targets of radiation-induced damage. In addition, eckol recovered the cell viability damaged by radiation via the inhibition of apoptosis. Irradiated cells with eckol treatment reduced the expression of bax, the activation of caspase 9 and caspase 3, which were induced by radiation. However, irradiated cells with eckol recovered the expression of bcl-2 and mitochondrial cytochrome c which were decreased by radiation. The anti-apoptotic effect of eckol exerted via the inhibition of mitogen-activated protein kinase kinase-4 (MKK4/SEK1)-c-Jun NH(2)-terminal kinase (JNK)-activator protein 1 (AP-1) cascades induced by radiation. In summary, the results suggest that eckol protects cells against the oxidative stress induced by radiation via the reduction of reactive oxygen species and the attenuation of activation in SEK1-JNK-AP-1 pathway.

Prostaglandin E2 Blocks Menadione-Induced Apoptosis through the Ras/Raf/Erk Signaling Pathway in Promonocytic Leukemia Cell Lines

PubMed Central

Yeo, Hyun-Seok; Shehzad, Adeeb; Lee, Young Sup

2012-01-01

Altered oxidative stress has long been observed in cancer cells, and this biochemical property of cancer cells represents a specific vulnerability that can be exploited for therapeutic benefit. The major role of an elevated oxidative stress for the efficacy of molecular targeted drugs is under investigation. Menadione is considered an attractive model for the study of oxidative stress, which can induce apoptosis in human leukemia HL-60 cell lines. Prostaglandin E2 (PGE2) via its receptors not only promotes cell survival but also reverses apoptosis and promotes cancer progression. Here, we present evidence for the biological role of PGE2 as a protective agent of oxidative stress-induced apoptosis in monocytic cells. Pretreatment of HL-60 cells with PGE2 markedly ameliorated the menadione-induced apoptosis and inhibited the degradation of PARP and lamin B. The EP2 receptor antagonist AH6809 abrogated the inhibitory effect of PGE2, suggesting the role of the EP2/cAMP system. The PKA inhibitor H89 also reversed apoptosis and decreased the PKA activity that was elevated 10-fold by PGE2. The treatment of HL-60 cells with NAC or zinc chloride showed a similar protective effect as with PGE2 on menadione-treated cells. Furthermore, PGE2 activated the Ras/Raf/MEK pathway, which in turn initiated ERK activation, and ultimately protected menadione-induced apoptosis. These results imply that PGE2 via cell survival pathways may protect oxidative stress-induced apoptosis in monocytic cells. This study warrants further pre-clinical investigation as well as application towards leukemia clinics. PMID:22450688

Stimulation of a shorter duration in the state of anergy by an invariant natural killer T cell agonist enhances its efficiency of protection from type 1 diabetes

PubMed Central

Tohn, R; Blumenfeld, H; Haeryfar, S M M; Veerapen, N; Besra, G S; Porcelli, S A; Delovitch, T L

2011-01-01

We have reported previously that treatment of non-obese diabetic (NOD) mice with the invariant natural killer T (iNK T) cell agonist α-galactosylceramide C26:0 (α-GalCer) or its T helper type 2 (Th2)-biasing derivative α-GalCer C20:2 (C20:2) protects against type 1 diabetes (T1D), with C20:2 yielding greater protection. After an initial response to α-GalCer, iNK T cells become anergic upon restimulation. While such anergic iNK T cells can induce tolerogenic dendritic cells (DCs) that mediate protection from T1D, chronic administration of α-GalCer also results in long-lasting anergy accompanied by significantly reduced iNK T cell frequencies, which raises concerns about its long-term therapeutic use. In this study, our objective was to understand more clearly the roles of anergy and induction of tolerogenic DCs in iNK T cell-mediated protection from T1D and to circumvent potential complications associated with α-GalCer. We demonstrate that NOD iNK T cells activated during multi-dose (MD) treatment in vivo with C20:2 enter into and exit from anergy more rapidly than after activation by α-GalCer. Importantly, this shorter duration of iNK T cells in the anergic state promotes the more rapid induction of tolerogenic DCs and reduced iNK T cell death, and enables C20:2 stimulated iNK T cells to elicit enhanced protection from T1D. Our findings further that suggest C20:2 is a more effective therapeutic drug than α-GalCer for protection from T1D. Moreover, the characteristics of C20:2 provide a basis of selection of next-generation iNK T cell agonists for the prevention of T1D. PMID:21361909

Pulsed electromagnetic fields promote survival and neuronal differentiation of human BM-MSCs.

PubMed

Urnukhsaikhan, Enerelt; Cho, Hyunjin; Mishig-Ochir, Tsogbadrakh; Seo, Young-Kwon; Park, Jung-Kueg

2016-04-15

Pulsed electromagnetic fields (PEMF) are known to affect biological properties such as differentiation, regulation of transcription factor and cell proliferation. However, the cell-protective effect of PEMF exposure is largely unknown. The aim of this study is to understand the mechanisms underlying PEMF-mediated suppression of apoptosis and promotion of survival, including PEMF-induced neuronal differentiation. Treatment of induced human BM-MSCs with PEMF increased the expression of neural markers such as NF-L, NeuroD1 and Tau. Moreover, treatment of induced human BM-MSCs with PEMF greatly decreased cell death in a dose- and time-dependent manner. There is evidence that Akt and Ras are involved in neuronal survival and protection. Activation of Akt and Ras results in the regulation of survival proteins such as Bad and Bcl-xL. Thus, the Akt/Ras signaling pathway may be a desirable target for enhancing cell survival and treatment of neurological disease. Our analyses indicated that PEMF exposure dramatically increased the activity of Akt, Rsk, Creb, Erk, Bcl-xL and Bad via phosphorylation. PEMF-dependent cell protection was reversed by pretreatment with LY294002, a specific inhibitor of phosphatidylinositol 3-kinase (PI3K). Our data suggest that the PI3K/Akt/Bad signaling pathway may be a possible mechanism for the cell-protective effects of PEMF. Copyright © 2016 Elsevier Inc. All rights reserved.

Protective effect of crocin on ultraviolet B‑induced dermal fibroblast photoaging.

PubMed

Deng, Mingwu; Li, Dong; Zhang, Yichen; Zhou, Guangdong; Liu, Wei; Cao, Yilin; Zhang, Wenjie

2018-06-11

Ultraviolet B (UVB) radiation induces the production of reactive oxygen species (ROS), resulting in the aging of dermal fibroblasts. Crocin, a bioactive constituent of Crocus sativus, possesses anti‑oxidation effects. The purpose of the present study was to evaluate the protective effect of crocin on UVB‑induced dermal fibroblast photoaging. Human dermal fibroblasts were isolated and cultured with different concentrations of crocin prior to and following exposure to UVB irradiation. The senescent phenotypes of cells were evaluated, including cell proliferation, cell cycle, senescence‑associated β‑galactosidase (SA‑β‑gal) expression, intracellular ROS, expression of antioxidant protein glutathione peroxidase 1 (GPX‑1) and extracellular matrix protein collagen type 1 (Col‑1). Crocin rescued the cell proliferation inhibited by UVB irradiation, prevented cell cycle arrest and markedly decreased the number of SA‑β‑gal‑positive cells. In addition, crocin reduced UVB‑induced ROS by increasing GPX‑1 expression and other direct neutralization effects. Furthermore, crocin promoted the expression of the extracellular matrix protein Col‑1. Crocin could effectively prevent UVB‑induced cell damage via the reduction of intracellular ROS; thus, it could potentially be used in the prevention of skin photoaging.

Exogenous heat shock protein HSP70 reduces response of human neuroblastoma cells to lipopolysaccharide.

PubMed

Yurinskaya, M M; Funikov, S Y; Evgen'ev, M B; Vinokurov, M G

2016-07-01

The effect of exogenous heat shock protein HSP70 and lipopolysaccharide (LPS) on the production of reactive oxygen species (ROS), TNFα secretion, and mRNA expression by human neuroblastoma SK-N-SH cells. It was shown that exogenous HSP70 protects neuroblastoma cells from the action of LPS. The protection mechanism of HSP70 includes a reduction in the production of ROS and TNFα and a decrease in the expression of TLR4 and IL-1β mRNA in SK-N-SH cells induced by LPS.

Platelet-Derived Growth Factor-BB Protects Mesenchymal Stem Cells (MSCs) Derived From Immune Thrombocytopenia Patients Against Apoptosis and Senescence and Maintains MSC-Mediated Immunosuppression

PubMed Central

Zhang, Jia-min; Feng, Fei-er; Wang, Qian-ming; Zhu, Xiao-lu; Fu, Hai-xia; Xu, Lan-ping; Liu, Kai-yan

2016-01-01

Immune thrombocytopenia (ITP) is characterized by platelet destruction and megakaryocyte dysfunction. Mesenchymal stem cells (MSCs) from ITP patients (MSC-ITP) do not exhibit conventional proliferative abilities and thus exhibit defects in immunoregulation, suggesting that MSC impairment might be a mechanism involved in ITP. Platelet-derived growth factor (PDGF) improves growth and survival in various cell types. Moreover, PDGF promotes MSC proliferation. The aim of the present study was to analyze the effects of PDGF-BB on MSC-ITP. We showed that MSC-ITP expanded more slowly and appeared flattened and larger. MSC-ITP exhibited increased apoptosis and senescence compared with controls. Both the intrinsic and extrinsic pathways account for the enhanced apoptosis. P53 and p21 expression were upregulated in MSC-ITP, but inhibition of p53 with pifithrin-α markedly inhibited apoptosis and senescence. Furthermore, MSCs from ITP patients showed a lower capacity for inhibiting the proliferation of activated T cells inducing regulatory T cells (Tregs) and suppressing the synthesis of anti-glycoprotein (GP)IIb-IIIa antibodies. PDGF-BB treatment significantly decreased the expression of p53 and p21 and increased survivin expression in MSC-ITP. In addition, the apoptotic rate and number of senescent cells in ITP MSCs were reduced. Their impaired ability for inhibiting activated T cells, inducing Tregs, and suppressing the synthesis of anti-GPIIb-IIIa antibodies was restored after PDGF-BB treatment. In conclusion, we have demonstrated that PDGF-BB protects MSCs derived from ITP patients against apoptosis, senescence, and immunomodulatory defects. This protective effect of PDGF-BB is likely mediated via the p53/p21 pathway, thus potentially providing a new therapeutic approach for ITP. Significance Immune thrombocytopenia (ITP) is characterized by platelet destruction and megakaryocyte dysfunction. Platelet-derived growth factor (PDGF) improves growth and survival in various cell types and promotes mesenchymal stem cell (MSC) proliferation. PDGF-BB protects MSCs derived from ITP patients against apoptosis, senescence, and immunomodulatory defects. This protective effect of PDGF-BB is likely mediated via the p53/p21 pathway, thus potentially providing a new therapeutic approach for ITP. PMID:27471307

Decursinol and decursin protect primary cultured rat cortical cells from glutamate-induced neurotoxicity.

PubMed

Kang, So Young; Kim, Young Choong

2007-06-01

We previously reported six neuroprotective decursinol derivatives, coumarins from Angelica gigas (Umbelliferae) roots. To elucidate the action patterns of decursinol derivatives, we investigated the neuroprotective effects of decursinol and decursin, which showed highly significant activity and were major constituents of A. gigas, using primary cultures of rat cortical cells in-vitro. At concentrations of 0.1-10.0 microM, both decursinol and decursin exerted a significant neuroprotective activity pretreatment and throughout treatment. In addition, decursin had a neuroprotective impact in the post-treatment paradigm implying that decursin might possess different action mechanisms from that of decursinol in the protection of neurons against glutamate injury. Both decursinol and decursin effectively reduced the glutamate-induced increased intracellular calcium ([Ca(2+)](i)) in cortical cells, suggesting that these two coumarins may exert neuroprotection by reducing calcium influx by overactivation of glutamate receptors. This suggestion was supported by the result that decursinol and decursin protected neurons against kainic acid (KA)-induced neurotoxicity better than against that induced by N-methyl-D-aspartate (NMDA). Moreover, both decursinol and decursin significantly prevented glutamate-induced decreases in glutathione, a cellular antioxidant, and glutathione peroxidase activity. In addition, both compounds efficiently reduced the overproduction of cellular peroxide in glutamate-injured cortical cells. These results suggested that both decursinol and decursin protected primary cultured rat cortical cells against glutamate-induced oxidative stress by both reducing calcium influx and acting on the cellular antioxidative defence system. Moreover, decursin is considered to probably have a different action mechanism from that of decursinol in protecting cortical cells against glutamate injury.

Clonogenicity of human leukemic cells protected from cell-lethal agents by heat shock protein 70

PubMed Central

Bases, Robert

2005-01-01

Pretreatment of human leukemia THP-1 cells with heat shock protein Hsp70 (Hsp70) protected them from the cell-lethal effects of the topoisomerase II inhibitor, lucanthone and from ionizing radiation. Cell viability was scored in clonogenic assays of single cells grown in liquid medium containing 0.5% methyl cellulose. Colonies were observed and rapidly scored after staining with the tetrazolium salt, 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide. The frequency of abasic sites in the deoxyribonucleic acid (DNA) of THP-1 cells was reduced when these cells were treated with Hsp70. Hsp70 is presumed to have protected the cells by promoting repair of cell DNA, in agreement with previous studies that showed that Hsp70 enhanced base excision repair by purified enzymes. The shoulders of radiation dose-response curves were enhanced by pretreatment of cells with Hsp70 and, importantly, were reduced when cells were transfected with ribonucleic acid designed to silence Hsp70. Hsp70 influenced repair of sublethal damage after radiation. PMID:15832946

Antiapoptotic effects of anthocyanin from the seed coat of black soybean against oxidative damage of human lens epithelial cell induced by H2O2.

PubMed

Mok, Jee Won; Chang, Dong-Jin; Joo, Choun-Ki

2014-11-01

To describe the protective effect of anthocyanin from black soybean in human lens epithelial cell line (HLE-B3) under H2O2-induced oxidative stress. Cytotoxicity of anthocyanin and H2O2 were determined by Cell Counting Kit-8 test. Viability of HLE-B3 cells under various H2O2 concentration (0, 50 and 100 μM) with or without pretreatment of anthocyanin (0, 50, 100 and 200 μg/ml) was measured. After quantifying the percentage of the apoptosis by Annexin V assay and APO-BrdU TUNEL assay, we conducted western blot and immunostaining of apoptosis-related molecules; Bcl2, BAD, BAX, p53 and caspase-3. To confirm the effect of anthocyanin on an ex vivo model, its effect on cultures of the lenses of porcine were examined. Anthocyanin reduced cell death of HLE-B3 under H2O2-induced oxidative stress in a dose-dependent manner. In Annexin V analysis, anthocyanin protected HLE-B3 cells from apoptosis. H2O2 increased the expression of BAX, BAD, p53 and caspase-3 in a time-dependent manner, those of which anthocyanin significantly decreased. On the other hand, Bcl2 was increased from anthocyanin-treated lens cells. And in anthocyanin-treated lens organ culture, transparency was maintained. This study showed that anthocyanin protects HLE-B3 cells under oxidative stress from apoptosis, and the mechanism of the effect is related to the intrinsic pathway of apoptosis. Anthocyanin has a potential in prevention of cataract.

The effect of resveratrol on protecting corneal epithelial cells from cytotoxicity caused by moxifloxacin and benzalkonium chloride.

PubMed

Tsai, Tzu-Yun; Chen, Ta-Ching; Wang, I-Jong; Yeh, Chao-Yuan; Su, Ming-Jai; Chen, Ruey-Hua; Tsai, Tzu-Hsun; Hu, Fung-Rong

2015-02-10

Moxifloxacin (MOX), a fourth generation fluoroquinolone (FQ), has a wide antibacterial spectrum, but may show cytotoxicity characterized by high productions of reactive oxygen species (ROS). This study investigated the protective role of a common antioxidant agent, resveratrol (trans-3,5,4'-trihydroxystilbene), against the cytotoxicity caused by MOX. Experiments were performed with a human corneal epithelial cell line (HCECs; ATCC-CRL-11515). Another commonly used FQ, levofloxacin (LEV), and the most commonly used preservatives, benzalkonium chloride (BAC), were also used for comparison with MOX. Cell viability and morphologic changes after treatment were evaluated with trypan blue exclusion assay, propidium iodine/annexin V-FITC staining, and flow cytometry. Chemiluminescence immunoassay was used for ROS quantification. MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, wound healing assay, and intracellular detections of oxidative stress were performed to evaluate the effects of resveratrol. The MOX group, similar to the BAC group, showed significant cell shrinkage and death compared with the LEV group. High ROS production in HCECs of MOX group was observed both by chemiluminescence immunoassay and intracellular images. Within the observations of MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay, live cell images, and wound healing process in vitro, the cytotoxic effects of the MOX and BAC groups were opposed by resveratrol. Human corneal epithelial cells pretreated with resveratrol demonstrated better cell viability and healing rate in the early stage. The protective effects of antioxidant agents indicate that MOX, similar to BAC, causes oxidative stress-related cell damage. The results also inspired us to think about a "supplementary regimen" to increase safety and decrease the adverse effect in the treatment of corneal infections. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

Protective Effect of Hibiscus Sabdariffa on Doxorubicin-induced Cytotoxicity in H9c2 Cardiomyoblast Cells

PubMed Central

Hosseini, Azar; Bakhtiari, Elham; Mousavi, Seyed Hadi

2017-01-01

Doxorubicin (DOX) is an effective anticancer drug. But its clinical application is limited, because DOX induces apoptosis in cardiomyocytes and it leads to permanent degenerative cardiomyopathy and heart failure. Recent trainings showed that Hibiscus sabdariffa exhibit pharmacological actions such as potent antioxidant. So, in this study we explored the protective effect of H. sabdariffa extract on doxorubicin-induced cytotoxicity in H9c2 cells. Cell viability was quantified by MTT assay. Apoptotic cells were determined using PI staining of DNA fragmentation by flowcytometry (sub-G1 peak). Cells were cultured with 5 μM DOX for 24 h to create the cell damage. H9c2 cells were pretreated with different concentrations (7.81-500 μg/mL) of H. sabdariffa extract (HSE) for 2 h before DOX treatment in all trials. Pretreatment with HSE increased cell viability at concentration of 31.25-500 μg/mL. Compared to control cells, apoptosis was induced in DOX treated cells after 24 h, (𝑃< 0.001). Pretreatment with HSE significantly decreased cell apoptosis after 24 hr at concentration of 31.25-250 μg/mL. Our results show that H. sabdariffa could exert the cardioprotective effects on DOX-induced toxicity partly by antiapoptotic activity. PMID:28979325

Protective Effect of Hibiscus Sabdariffa on Doxorubicin-induced Cytotoxicity in H9c2 Cardiomyoblast Cells.

PubMed

Hosseini, Azar; Bakhtiari, Elham; Mousavi, Seyed Hadi

2017-01-01

Doxorubicin (DOX) is an effective anticancer drug. But its clinical application is limited, because DOX induces apoptosis in cardiomyocytes and it leads to permanent degenerative cardiomyopathy and heart failure. Recent trainings showed that Hibiscus sabdariffa exhibit pharmacological actions such as potent antioxidant. So, in this study we explored the protective effect of H. sabdariffa extract on doxorubicin-induced cytotoxicity in H9c2 cells. Cell viability was quantified by MTT assay. Apoptotic cells were determined using PI staining of DNA fragmentation by flowcytometry (sub-G1 peak). Cells were cultured with 5 μM DOX for 24 h to create the cell damage. H9c2 cells were pretreated with different concentrations (7.81-500 μg/mL) of H. sabdariffa extract (HSE) for 2 h before DOX treatment in all trials. Pretreatment with HSE increased cell viability at concentration of 31.25-500 μg/mL. Compared to control cells, apoptosis was induced in DOX treated cells after 24 h, (< 0.001). Pretreatment with HSE significantly decreased cell apoptosis after 24 hr at concentration of 31.25-250 μg/mL. Our results show that H. sabdariffa could exert the cardioprotective effects on DOX-induced toxicity partly by antiapoptotic activity.

Protection against Chlamydia psittaci in mice conferred by Lyt-2+ T cells.

PubMed Central

Buzoni-Gatel, D; Guilloteau, L; Bernard, F; Bernard, S; Chardès, T; Rocca, A

1992-01-01

A murine model was used to study the respective roles of L3T4+ and Lyt-2+ T cells in protection against Chlamydia psittaci. Donor mice were intravenously (i.v.) infected with 1 x 10(5) plaque-forming units (PFU) per mice of live C. psittaci. One month after inoculation, splenic cells from donors were transferred into syngenic recipients (5 x 10(7) cells/mouse). As measured by splenic colonization on Day 6 after i.v. challenge (1 x 10(5) PFU/mouse), transfer with primed (untreated) cells conferred a 3 log protection in this model. In vitro treatment, before transfer, of splenic cells with anti-Lyt-2 monoclonal antibody (mAb) and complement, markedly impaired the protection in comparison with control mice transferred with primed untreated cells, whereas treatment with anti-L3T4 mAb did not reduce the transferred protection. Resistance to a reinfection with C. psittaci was also studied after selective in vivo depletion of L3T4+ and Lyt-2+ T cells. One month after primary infection, mice were treated with anti-L3T4 or anti-Lyt-2 mAb and challenged thereafter (i.v., 1 x 10(5) PFU). The splenic colonization on Day 6 after challenge demonstrated that treatment with anti-Lyt-2 mAb impaired resistance against a subsequent infection with C. psittaci. Treatment with anti-L3T4 mAb in vivo had no effect on protection, as previously described in vitro. The mechanisms by which Lyt-2+ T cells could participate in the elimination of bacteria were discussed. PMID:1427980

Adipose tissue-derived stem cell secreted IGF-1 protects myoblasts from the negative effect of myostatin.

PubMed

Gehmert, Sebastian; Wenzel, Carina; Loibl, Markus; Brockhoff, Gero; Huber, Michaela; Krutsch, Werner; Nerlich, Michael; Gosau, Martin; Klein, Silvan; Schreml, Stephan; Prantl, Lukas; Gehmert, Sanga

2014-01-01

Myostatin, a TGF-β family member, is associated with inhibition of muscle growth and differentiation and might interact with the IGF-1 signaling pathway. Since IGF-1 is secreted at a bioactive level by adipose tissue-derived mesenchymal stem cells (ASCs), these cells (ASCs) provide a therapeutic option for Duchenne Muscular Dystrophy (DMD). But the protective effect of stem cell secreted IGF-1 on myoblast under high level of myostatin remains unclear. In the present study murine myoblasts were exposed to myostatin under presence of ASCs conditioned medium and investigated for proliferation and apoptosis. The protective effect of IGF-1 was further examined by using IGF-1 neutralizing and receptor antibodies as well as gene silencing RNAi technology. MyoD expression was detected to identify impact of IGF-1 on myoblasts differentiation when exposed to myostatin. IGF-1 was accountable for 43.6% of the antiapoptotic impact and 48.8% for the proliferative effect of ASCs conditioned medium. Furthermore, IGF-1 restored mRNA and protein MyoD expression of myoblasts under risk. Beside fusion and transdifferentiation the beneficial effect of ASCs is mediated by paracrine secreted cytokines, particularly IGF-1. The present study underlines the potential of ASCs as a therapeutic option for Duchenne muscular dystrophy and other dystrophic muscle diseases.

Location and Dynamics of the Immunodominant CD8 T Cell Response to SIVΔnef Immunization and SIVmac251 Vaginal Challenge

PubMed Central

Sasikala-Appukuttan, Arun K.; Kim, Hyeon O.; Kinzel, Nikilyn J.; Hong, Jung Joo; Smith, Anthony J.; Wagstaff, Reece; Reilly, Cavan; Piatak, Michael; Lifson, Jeffrey D.; Reeves, R. Keith; Johnson, R. Paul; Haase, Ashley T.; Skinner, Pamela J.

2013-01-01

Live-attenuated SIV vaccines (LAVs) have been the most effective to date in preventing or partially controlling infection by wild-type SIV in non-human primate models of HIV-1 transmission to women acting by mechanisms of protection that are not well understood. To gain insights into mechanisms of protection by LAVs that could aid development of effective vaccines to prevent HIV-1 transmission to women, we used in situ tetramer staining to determine whether increased densities or changes in the local distribution of SIV-specific CD8 T cells correlated with the maturation of SIVΔnef vaccine-induced protection prior to and after intra-vaginal challenge with wild-type SIVmac251. We evaluated the immunodominant Mamu-A1*001:01/Gag (CM9) and Mamu-A1*001:01/Tat (SL8) epitope response in genital and lymphoid tissues, and found that tetramer+ cells were present at all time points examined. In the cervical vaginal tissues, most tetramer+ cells were distributed diffusely throughout the lamina propria or co-localized with other CD8 T cells within lymphoid aggregates. The distribution and densities of the tetramer+ cells at the portal of entry did not correlate with the maturation of protection or change after challenge. Given these findings, we discuss the possibility that changes in other aspects of the immune system, including the quality of the resident population of virus-specific effector CD8 T cells could contribute to maturation of protection, as well as the potential for vaccine strategies that further increase the size and quality of this effector population to prevent HIV-1 transmission. PMID:24349100

Cedrin identified from Cedrus deodara (Roxb.) G. Don protects PC12 cells against neurotoxicity induced by Aβ1-42.

PubMed

Zhao, Zhiwei; Dong, Zhanfei; Ming, Jie; Liu, Yan

2018-06-01

Alzheimer's disease is a severe neurodegenerative disease affecting elder worldwide and closely related to the neurotoxicity induced by amyloid β. To find efficient therapeutics, we have investigated the protective effects of cedrin from Cedrus deodara (Roxb.) G. Don on PC12 cells against the neurotoxicity induced by amyloid β 1-42 . The results have shown the viability of PC12 cells injured by amyloid β 1-42 can be improved by cedrin. Cedrin can reduce reacrive oxygen species overproduction, increase the activity of superoxide dismutase and decrease malondialdehyde content. Meanwhile, the loss of mitochondrial membrane potential and mitochondrial permeability transition pore opening in PC12 cells, and elevated Caspase-3 activity, downregulated Bcl-2 and upregulated Bax are meliorated. These results demonstrate the protective effect of cedrin is related to the inhibition of oxidative stress, improvement of mitochondrial dysfunction and suppression of apoptosis. This investigation gives evidences for the application of cedrin in practice and further investigation in vivo.

A Small Peptide (CEL-1000) Derived from the β-Chain of the Human Major Histocompatibility Complex Class II Molecule Induces Complete Protection against Malaria in an Antigen-Independent Manner

PubMed Central

Charoenvit, Yupin; Brice, Gary T.; Bacon, David; Majam, Victoria; Williams, Jackie; Abot, Esteban; Ganeshan, Harini; Sedegah, Martha; Doolan, Denise L.; Carucci, Daniel J.; Zimmerman, Daniel H.

2004-01-01

CEL-1000 (DGQEEKAGVVSTGLIGGG) is a novel potential preventative and therapeutic agent. We report that CEL-1000 confers a high degree of protection against Plasmodium sporozoite challenge in a murine model of malaria, as shown by the total absence of blood stage infection following challenge with 100 sporozoites (100% protection) and by a substantial reduction (400-fold) of liver stage parasite RNA following challenge with 50,000 sporozoites. CEL-1000 protection was demonstrated in A/J (H-2a) and C3H/HeJ (H-2k) mice but not in BALB/c (H-2d) or CAF1 (A/J × BALB/c F1 hybrid) mice. In CEL-1000-treated and protected mice, high levels of gamma interferon (IFN-γ) in serum and elevated frequencies of hepatic and splenic CD4+ IFN-γ-positive T cells were detected 24 h after administration of an additional dose of CEL-1000. Treatment of A/J mice that received CEL-1000 with antibodies against IFN-γ just prior to challenge abolished the protection, and a similar treatment with antibodies against CD4+ T cells partially reduced the level of protection, while treatment with control antibodies or antibodies specific for interleukin-12 (IL-12), CD8+ T cells, or NK cells had no effect. Our data establish that the protection induced by CEL-1000 is dependent on IFN-γ and is partially dependent on CD4+ T cells but is independent of CD8+ T cells, NK cells, and IL-12 at the effector phase and does not induce a detectable antibody response. PMID:15215094

A small peptide (CEL-1000) derived from the beta-chain of the human major histocompatibility complex class II molecule induces complete protection against malaria in an antigen-independent manner.

PubMed

Charoenvit, Yupin; Brice, Gary T; Bacon, David; Majam, Victoria; Williams, Jackie; Abot, Esteban; Ganeshan, Harini; Sedegah, Martha; Doolan, Denise L; Carucci, Daniel J; Zimmerman, Daniel H

2004-07-01

CEL-1000 (DGQEEKAGVVSTGLIGGG) is a novel potential preventative and therapeutic agent. We report that CEL-1000 confers a high degree of protection against Plasmodium sporozoite challenge in a murine model of malaria, as shown by the total absence of blood stage infection following challenge with 100 sporozoites (100% protection) and by a substantial reduction (400-fold) of liver stage parasite RNA following challenge with 50,000 sporozoites. CEL-1000 protection was demonstrated in A/J (H-2(a)) and C3H/HeJ (H-2(k)) mice but not in BALB/c (H-2(d)) or CAF1 (A/J x BALB/c F(1) hybrid) mice. In CEL-1000-treated and protected mice, high levels of gamma interferon (IFN-gamma) in serum and elevated frequencies of hepatic and splenic CD4+ IFN-gamma-positive T cells were detected 24 h after administration of an additional dose of CEL-1000. Treatment of A/J mice that received CEL-1000 with antibodies against IFN-gamma just prior to challenge abolished the protection, and a similar treatment with antibodies against CD4+ T cells partially reduced the level of protection, while treatment with control antibodies or antibodies specific for interleukin-12 (IL-12), CD8+ T cells, or NK cells had no effect. Our data establish that the protection induced by CEL-1000 is dependent on IFN-gamma and is partially dependent on CD4+ T cells but is independent of CD8+ T cells, NK cells, and IL-12 at the effector phase and does not induce a detectable antibody response.

L-carnitine protects against nickel-induced neurotoxicity by maintaining mitochondrial function in Neuro-2a cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

He Mindi; Xu Shangcheng; Lu Yonghui

Mitochondrial dysfunction is thought to be a part of the mechanism underlying nickel-induced neurotoxicity. L-carnitine (LC), a quaternary ammonium compound biosynthesized from the amino acids lysine and methionine in all mammalian species, manifests its neuroprotective effects by improving mitochondrial energetics and function. The purpose of this study was to investigate whether LC could efficiently protect against nickel-induced neurotoxicity. Here, we exposed a mouse neuroblastoma cell line (Neuro-2a) to different concentrations of nickel chloride (NiCl{sub 2}) (0.25, 0.5, 1, and 2 mM) for 24 h, or to 0.5 mM and 1 mM NiCl{sub 2} for various periods (0, 3, 6, 12,more » or 24 h). We found that nickel significantly increased the cell viability loss and lactate dehydrogenase (LDH) release in Neuro-2a cells. In addition, nickel exposure significantly elevated reactive oxygen species (ROS) and malondialdehyde (MDA) levels, disrupted the mitochondrial membrane potential ({Delta}{Psi}{sub m}), reduced adenosine-5'-triphosphate (ATP) concentrations and decreased mitochondrial DNA (mtDNA) copy numbers and mtRNA transcript levels. However, all of the cytotoxicities and mitochondrial dysfunctions that were triggered by nickel were efficiently attenuated by pretreatment with LC. These protective effects of LC may be attributable to its role in maintaining mitochondrial function in nickel-treated cells. Our results suggest that LC may have great pharmacological potential in protecting against the adverse effects of nickel in the nervous system.« less

Hypoxic-Preconditioned Bone Marrow Stem Cell Medium Significantly Improves Outcome After Retinal Ischemia in Rats

PubMed Central

Roth, Steven; Dreixler, John C.; Mathew, Biji; Balyasnikova, Irina; Mann, Jacob R.; Boddapati, Venkat; Xue, Lai; Lesniak, Maciej S.

2016-01-01

Purpose We have previously demonstrated the protective effect of bone marrow stem cell (BMSC)-conditioned medium in retinal ischemic injury. We hypothesized here that hypoxic preconditioning of stem cells significantly enhances the neuroprotective effect of the conditioned medium and thereby augments the protective effect in ischemic retina. Methods Rats were subjected to retinal ischemia by increasing intraocular pressure to 130 to 135 mm Hg for 55 minutes. Hypoxic-preconditioned, hypoxic unconditioned, or normoxic medium was injected into the vitreous 24 hours after ischemia ended. Recovery was assessed 7 days after injections by comparing electroretinography measurements, histologic examination, and apoptosis (TUNEL, terminal deoxynucleotidyl transferase–mediated dUTP nick end labeling assay). To compare proteins secreted into the medium in the groups and the effect of hypoxic exposure, we used rat cytokine arrays. Results Eyes injected with hypoxic BMSC–conditioned medium 24 hours after ischemia demonstrated significantly enhanced return of retinal function, decreased retinal ganglion cell layer loss, and attenuated apoptosis compared to those administered normoxic or hypoxic unconditioned medium. Hypoxic-preconditioned medium had 21 significantly increased protein levels compared to normoxic medium. Conclusions The medium from hypoxic-preconditioned BMSCs robustly restored retinal function and prevented cell loss after ischemia when injected 24 hours after ischemia. The protective effect was even more pronounced than in our previous studies of normoxic conditioned medium. Prosurvival signals triggered by the secretome may play a role in this neuroprotective effect. PMID:27367588

Immune Mechanisms Responsible for Vaccination against and Clearance of Mucosal and Lymphatic Norovirus Infection

PubMed Central

Chachu, Karen A.; LoBue, Anna D.; Strong, David W.; Baric, Ralph S.; Virgin, Herbert W.

2008-01-01

Two cardinal manifestations of viral immunity are efficient clearance of acute infection and the capacity to vaccinate against secondary viral exposure. For noroviruses, the contributions of T cells to viral clearance and vaccination have not been elucidated. We report here that both CD4 and CD8 T cells are required for efficient clearance of primary murine norovirus (MNV) infection from the intestine and intestinal lymph nodes. Further, long-lasting protective immunity was generated by oral live virus vaccination. Systemic vaccination with the MNV capsid protein also effectively protected against mucosal challenge, while vaccination with the capsid protein of the distantly related human Lordsdale virus provided partial protection. Fully effective vaccination required a broad immune response including CD4 T cells, CD8 T cells, and B cells, but the importance of specific immune cell types varied between the intestine and intestinal lymph nodes. Perforin, but not interferon gamma, was required for clearance of MNV infection by adoptively transferred T lymphocytes from vaccinated hosts. These studies prove the feasibility of both mucosal and systemic vaccination against mucosal norovirus infection, demonstrate tissue specificity of norovirus immune cells, and indicate that efficient vaccination strategies should induce potent CD4 and CD8 T cell responses. PMID:19079577

Cycloheximide- and puromycin-induced heat resistance: different effects on cytoplasmic and nuclear luciferases

PubMed Central

Michels, Annemieke A; Kanon, Bart; Konings, Antonius W.T; Bensaude, Olivier; Kampinga, Harm H

2000-01-01

Inhibition of translation can result in cytoprotection against heat shock. The mechanism of this protection has remained elusive so far. Here, the thermoprotective effects of the translation inhibitor cycloheximide (CHX) and puromycin were investigated, using as reporter firefly luciferase localized either in the nucleus or in the cytoplasm. A short preincubation of O23 cells with either translation inhibitor was found to attenuate the heat inactivation of a luciferase directed into the cytoplasm, whereas the heat sensitivity of a nuclear-targeted luciferase remained unaffected. After a long-term CHX pretreatment, both luciferases were more heat resistant. Both the cytoplasmic and the nuclear luciferase are protected against heat-induced inactivation in thermotolerant cells and in cells overexpressing heat shock protein (Hsp)70. CHX incubations further attenuated cytoplasmic luciferase inactivation in thermotolerant and in Hsp70 overexpressing cells, even when Hsp70-mediated protection was saturated. It is concluded that protection by translation inhibition is unlikely due to an increase in the pool of free Hsps normally engaged in translation and released from the nascent polypeptide chains on the ribosomes. Rather, a decrease in nascent chains and thermolabile polypeptides may account for the heat resistance promoted by inhibitors of translation. PMID:11005376

Coenzyme Q10 Protects Human Endothelial Cells from β-Amyloid Uptake and Oxidative Stress-Induced Injury

PubMed Central

Durán-Prado, Mario; Frontiñán, Javier; Santiago-Mora, Raquel; Peinado, Juan Ramón; Parrado-Fernández, Cristina; Gómez-Almagro, María Victoria; Moreno, María; López-Domínguez, José Alberto; Villalba, José Manuel; Alcaín, Francisco J.

2014-01-01

Neuropathological symptoms of Alzheimer's disease appear in advances stages, once neuronal damage arises. Nevertheless, recent studies demonstrate that in early asymptomatic stages, ß-amyloid peptide damages the cerebral microvasculature through mechanisms that involve an increase in reactive oxygen species and calcium, which induces necrosis and apoptosis of endothelial cells, leading to cerebrovascular dysfunction. The goal of our work is to study the potential preventive effect of the lipophilic antioxidant coenzyme Q (CoQ) against ß-amyloid-induced damage on human endothelial cells. We analyzed the protective effect of CoQ against Aβ-induced injury in human umbilical vein endothelial cells (HUVECs) using fluorescence and confocal microscopy, biochemical techniques and RMN-based metabolomics. Our results show that CoQ pretreatment of HUVECs delayed Aβ incorporation into the plasma membrane and mitochondria. Moreover, CoQ reduced the influx of extracellular Ca2+, and Ca2+ release from mitochondria due to opening the mitochondrial transition pore after β-amyloid administration, in addition to decreasing O2 .− and H2O2 levels. Pretreatment with CoQ also prevented ß-amyloid-induced HUVECs necrosis and apoptosis, restored their ability to proliferate, migrate and form tube-like structures in vitro, which is mirrored by a restoration of the cell metabolic profile to control levels. CoQ protected endothelial cells from Aβ-induced injury at physiological concentrations in human plasma after oral CoQ supplementation and thus could be a promising molecule to protect endothelial cells against amyloid angiopathy. PMID:25272163

Airway-Resident Memory CD8 T Cells Provide Antigen-Specific Protection against Respiratory Virus Challenge through Rapid IFN-γ Production.

PubMed

McMaster, Sean R; Wilson, Jarad J; Wang, Hong; Kohlmeier, Jacob E

2015-07-01

CD8 airway resident memory T (TRM) cells are a distinctive TRM population with a high turnover rate and a unique phenotype influenced by their localization within the airways. Their role in mediating protective immunity to respiratory pathogens, although suggested by many studies, has not been directly proven. This study provides definitive evidence that airway CD8 TRM cells are sufficient to mediate protection against respiratory virus challenge. Despite being poorly cytolytic in vivo and failing to expand after encountering Ag, airway CD8 TRM cells rapidly express effector cytokines, with IFN-γ being produced most robustly. Notably, established airway CD8 TRM cells possess the ability to produce IFN-γ faster than systemic effector memory CD8 T cells. Furthermore, naive mice receiving intratracheal transfer of airway CD8 TRM cells lacking the ability to produce IFN-γ were less effective at controlling pathogen load upon heterologous challenge. This direct evidence of airway CD8 TRM cell-mediated protection demonstrates the importance of these cells as a first line of defense for optimal immunity against respiratory pathogens and suggests they should be considered in the development of future cell-mediated vaccines. Copyright © 2015 by The American Association of Immunologists, Inc.

Acetyl salicylic acid protected against heat stress damage in chicken myocardial cells and may associate with induced Hsp27 expression.

PubMed

Wu, Di; Xu, Jiao; Song, Erbao; Tang, Shu; Zhang, Xiaohui; Kemper, N; Hartung, J; Bao, Endong

2015-07-01

We investigated whether acetyl salicylic acid (ASA) protects chicken myocardial cells from heat stress-mediated damage in vivo and whether the induction of Hsp27 expression is connected with this function. Pathological changes, damage-related enzyme levels, and Hsp27 expression were studied in chickens following heat stress (40 ± 1 °C for 0, 1, 2, 3, 5, 7, 10, 15, or 24 h, respectively) with or without ASA administration (1 mg/kg BW, 2 h prior). Appearance of pathological lesions such as degenerations and karyopyknosis as well as the myocardial damage-related enzyme activation indicated that heat stress causes considerable injury to the myocardial cells in vivo. Myocardial cell injury was most serious in chickens exposed to heat stress without prior ASA administration; meanwhile, ASA pretreatment acted protective function against high temperature-induced injury. Hsp27 expression was induced under all experimental conditions but was one-fold higher in the ASA-pretreated animals (0.3138 ± 0.0340 ng/mL) than in untreated animals (0.1437 ± 0.0476 ng/mL) 1 h after heat stress exposure, and such an increase was sustained over the length of the experiment. Our findings indicate that pretreatment with ASA protects chicken myocardial cells from acute heat stress in vivo with almost no obvious side effects, and this protection may involve an enhancement of Hsp27 expression. However, the detailed mechanisms underlying this effect require further investigation.

Analysis of Vaginal Cell Populations during Experimental Vaginal Candidiasis

PubMed Central

Fidel, Paul L.; Luo, Wei; Steele, Chad; Chabain, Joseph; Baker, Marc; Wormley, Floyd

1999-01-01

Studies with an estrogen-dependent murine model of vaginal candidiasis suggest that local cell-mediated immunity (CMI) is more important than systemic CMI for protection against vaginitis. The present study, however, showed that, compared to uninfected mice, little to no change in the percentage or types of vaginal T cells occurred during a primary vaginal infection or during a secondary vaginal infection where partial protection was observed. Furthermore, depletion of polymorphonuclear leukocytes (PMN) had no effect on infection in the presence or absence of pseudoestrus. These results indicate a lack of demonstrable effects by systemic CMI or PMN against vaginitis and suggest that if local T cells are important, they are functioning without showing significant increases in numbers within the vaginal mucosa during infection. PMID:10338532

Redox-active cerium oxide nanoparticles protect human dermal fibroblasts from PQ-induced damage.

PubMed

von Montfort, Claudia; Alili, Lirija; Teuber-Hanselmann, Sarah; Brenneisen, Peter

2015-01-01

Recently, it has been published that cerium (Ce) oxide nanoparticles (CNP; nanoceria) are able to downregulate tumor invasion in cancer cell lines. Redox-active CNP exhibit both selective pro-oxidative and antioxidative properties, the first being responsible for impairment of tumor growth and invasion. A non-toxic and even protective effect of CNP in human dermal fibroblasts (HDF) has already been observed. However, the effect on important parameters such as cell death, proliferation and redox state of the cells needs further clarification. Here, we present that nanoceria prevent HDF from reactive oxygen species (ROS)-induced cell death and stimulate proliferation due to the antioxidative property of these particles. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Skin cell protection against UVA by Sideroxyl, a new antioxidant complementary to sunscreens.

PubMed

Pygmalion, Marie-Jocelyne; Ruiz, Laetitia; Popovic, Evelyne; Gizard, Julie; Portes, Pascal; Marat, Xavier; Lucet-Levannier, Karine; Muller, Benoit; Galey, Jean-Baptiste

2010-12-01

Oxidative stress resulting from photosensitized ROS production in skin is widely accepted as the main contributor to the deleterious effects of UVA exposure. Among the mechanisms known to be involved in UVA-induced oxidative damage, iron plays a central role. UVA radiation of skin cells induces an immediate release of iron, which can then act as a catalyst for uncontrolled oxidation reactions of cell components. Such site-specific damage can scarcely be counteracted by classical antioxidants. In contrast, iron chelators potentially offer an effective way to protect skin against UVA insults. However, iron chelation is very difficult to achieve without disturbing iron homeostasis or inducing iron depletion. A novel compound was developed to avoid these potentially harmful side effects. Sideroxyl was designed to acquire its strong chelating capability only during oxidative stress according to an original process of intramolecular hydroxylation. Herein, we describe in vitro results demonstrating the protective efficiency of Sideroxyl against deleterious effects of UVA at the molecular, cellular, and tissular levels. First, the Sideroxyl diacid form protects a model protein against UVA-induced photosensitized carbonylation. Second, intracellular ROS are dose-dependently decreased in the presence of Sideroxyl in both human cultured fibroblasts and human keratinocytes. Third, Sideroxyl protects normal human fibroblasts against UVA-induced DNA damage as measured by the comet assay and MMP-1 production. Finally, Sideroxyl provides protection against UVA-induced alterations in human reconstructed skin. These results suggest that Sideroxyl may prevent UVA-induced damage in human skin as a complement to sunscreens, especially in the long-wavelength UVA range. Copyright © 2010 Elsevier Inc. All rights reserved.

Galantamine and carbon monoxide protect brain microvascular endothelial cells by heme oxygenase-1 induction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nakao, Atsunori; Thomas E Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA 15213; Kaczorowski, David J.

2008-03-14

Galantamine, a reversible inhibitor of acetylcholine esterase (AChE), is a novel drug treatment for mild to moderate Alzheimer's disease and vascular dementia. Interestingly, it has been suggested that galantamine treatment is associated with more clinical benefit in patients with mild-to-moderate Alzheimer disease compared to other AChE inhibitors. We hypothesized that the protective effects of galantamine would involve induction of the protective gene, heme oxygenase-1 (HO-1), in addition to enhancement of the cholinergic system. Brain microvascular endothelial cells (mvECs) were isolated from spontaneous hypertensive rats. Galantamine significantly reduced H{sub 2}O{sub 2}-induced cell death of mvECs in association with HO-1 induction. Thesemore » protective effects were completely reversed by nuclear factor-{kappa}B (NF-{kappa}B) inhibition or HO inhibition. Furthermore, galantamine failed to induce HO-1 in mvECs which lack inducible nitric oxide synthase (iNOS), supplementation of a nitric oxide (NO) donor or iNOS gene transfection on iNOS-deficient mvECs resulted in HO-1 induction with galantamine. These data suggest that the protective effects of galantamine require NF-{kappa}B activation and iNOS expression, in addition to HO-1. Likewise, carbon monoxide (CO), one of the byproducts of HO, up-regulated HO-1 and protected mvECs from oxidative stress in a similar manner. Our data demonstrate that galantamine mediates cytoprotective effects on mvECs through induction HO-1. This pharmacological action of galantamine may, at least in part, account for the superior clinical efficacy of galantamine in vascular dementia and Alzheimer disease.« less

Nasal Acai polysaccharides potentiate innate immunity to protect against pulmonary Francisella tularensis and Burkholderia pseudomallei Infections.

PubMed

Skyberg, Jerod A; Rollins, MaryClare F; Holderness, Jeff S; Marlenee, Nicole L; Schepetkin, Igor A; Goodyear, Andrew; Dow, Steven W; Jutila, Mark A; Pascual, David W

2012-01-01

Pulmonary Francisella tularensis and Burkholderia pseudomallei infections are highly lethal in untreated patients, and current antibiotic regimens are not always effective. Activating the innate immune system provides an alternative means of treating infection and can also complement antibiotic therapies. Several natural agonists were screened for their ability to enhance host resistance to infection, and polysaccharides derived from the Acai berry (Acai PS) were found to have potent abilities as an immunotherapeutic to treat F. tularensis and B. pseudomallei infections. In vitro, Acai PS impaired replication of Francisella in primary human macrophages co-cultured with autologous NK cells via augmentation of NK cell IFN-γ. Furthermore, Acai PS administered nasally before or after infection protected mice against type A F. tularensis aerosol challenge with survival rates up to 80%, and protection was still observed, albeit reduced, when mice were treated two days post-infection. Nasal Acai PS administration augmented intracellular expression of IFN-γ by NK cells in the lungs of F. tularensis-infected mice, and neutralization of IFN-γ ablated the protective effect of Acai PS. Likewise, nasal Acai PS treatment conferred protection against pulmonary infection with B. pseudomallei strain 1026b. Acai PS dramatically reduced the replication of B. pseudomallei in the lung and blocked bacterial dissemination to the spleen and liver. Nasal administration of Acai PS enhanced IFN-γ responses by NK and γδ T cells in the lungs, while neutralization of IFN-γ totally abrogated the protective effect of Acai PS against pulmonary B. pseudomallei infection. Collectively, these results demonstrate Acai PS is a potent innate immune agonist that can resolve F. tularensis and B. pseudomallei infections, suggesting this innate immune agonist has broad-spectrum activity against virulent intracellular pathogens.

Method for protection against genotoxic mutagenesis

DOEpatents

Grdina, David J.

1996-01-01

A method and pharmaceutical for protecting against genotoxic damage in irradiated cells. Reduction of mutations at the hypoxanthine-guanine phosphoribosyl transferase locus is accomplished by administering an effective dose of a compound having protected sulfhydryl groups which metabolize in vivo to produce both free sulfhydryl groups and disulfides.

Protective effects of l-carnitine and piracetam against mitochondrial permeability transition and PC3 cell necrosis induced by simvastatin.

PubMed

Costa, Rute A P; Fernandes, Mariana P; de Souza-Pinto, Nadja C; Vercesi, Aníbal E

2013-02-15

Mitochondrial oxidative stress followed by membrane permeability transition (MPT) has been considered as a possible mechanism for statins cytotoxicity. Statins use has been associated with reduced risk of cancer incidence, especially prostate cancer. Here we investigated the pathways leading to simvastatin-induced prostate cancer cell death as well as the mechanisms of cell death protection by l-carnitine or piracetam. These compounds are known to prevent and/or protect against cell death mediated by oxidative mitochondrial damage induced by a variety of conditions, either in vivo or in vitro. The results provide evidence that simvastatin induced MPT and cell necrosis were sensitive to either l-carnitine or piracetam in a dose-dependent fashion and mediated by additive mechanisms. When combined, l-carnitine and piracetam acted at concentrations significantly lower than they act individually. These results shed new light into both the cytotoxic mechanisms of statins and the mechanisms underlying the protection against MPT and cell death by the compounds l-carnitine and piracetam. Copyright © 2013 Elsevier B.V. All rights reserved.

Skin-resident memory CD4+ T cells enhance protection against Leishmania major infection.

PubMed

Glennie, Nelson D; Yeramilli, Venkata A; Beiting, Daniel P; Volk, Susan W; Weaver, Casey T; Scott, Phillip

2015-08-24

Leishmaniasis causes a significant disease burden worldwide. Although Leishmania-infected patients become refractory to reinfection after disease resolution, effective immune protection has not yet been achieved by human vaccines. Although circulating Leishmania-specific T cells are known to play a critical role in immunity, the role of memory T cells present in peripheral tissues has not been explored. Here, we identify a population of skin-resident Leishmania-specific memory CD4+ T cells. These cells produce IFN-γ and remain resident in the skin when transplanted by skin graft onto naive mice. They function to recruit circulating T cells to the skin in a CXCR3-dependent manner, resulting in better control of the parasites. Our findings are the first to demonstrate that CD4+ TRM cells form in response to a parasitic infection, and indicate that optimal protective immunity to Leishmania, and thus the success of a vaccine, may depend on generating both circulating and skin-resident memory T cells. © 2015 Glennie et al.

Skin-resident memory CD4+ T cells enhance protection against Leishmania major infection

PubMed Central

Glennie, Nelson D.; Yeramilli, Venkata A.; Beiting, Daniel P.; Volk, Susan W.; Weaver, Casey T.

2015-01-01

Leishmaniasis causes a significant disease burden worldwide. Although Leishmania-infected patients become refractory to reinfection after disease resolution, effective immune protection has not yet been achieved by human vaccines. Although circulating Leishmania-specific T cells are known to play a critical role in immunity, the role of memory T cells present in peripheral tissues has not been explored. Here, we identify a population of skin-resident Leishmania-specific memory CD4+ T cells. These cells produce IFN-γ and remain resident in the skin when transplanted by skin graft onto naive mice. They function to recruit circulating T cells to the skin in a CXCR3-dependent manner, resulting in better control of the parasites. Our findings are the first to demonstrate that CD4+ TRM cells form in response to a parasitic infection, and indicate that optimal protective immunity to Leishmania, and thus the success of a vaccine, may depend on generating both circulating and skin-resident memory T cells. PMID:26216123

Polyphenolic compounds with antioxidant potential and neuro-protective effect from Cimicifuga dahurica (Turcz.) Maxim.

PubMed

Qin, Rulan; Zhao, Ying; Zhao, Yudan; Zhou, Wanrong; Lv, Chongning; Lu, Jincai

2016-12-01

Three new phenolic compounds (1-3), along with five known compounds (4-8) were isolated from the rhizome of Cimicifuga dahurica (Turcz.) Maxim. Their structures were elucidated by spectroscopic methods including 1D-NMR, 2D-NMR and HR-MS techniques. DPPH method and protective effect on PC12 cells against H 2 O 2 -induced oxidative damage model were carried to evaluate the antioxidant capability of these compounds. Compound 5 showed significant antioxidant activity with IC 50 values 9.33μM in DPPH assay and compound 2 displayed marked neuro-protective effect with 87.65% cell viability at the concentration of 10μM. Additionally, the possible structure-activity relationships of these phenolic compounds were tentatively discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

Improving the Safety of Lithium-Ion Battery via a Redox Shuttle Additive 2,5-Di- tert-butyl-1,4-bis(2-methoxyethoxy)benzene (DBBB).

PubMed

Leonet, Olatz; Colmenares, Luis C; Kvasha, Andriy; Oyarbide, Mikel; Mainar, Aroa R; Glossmann, Tobias; Blázquez, J Alberto; Zhang, Zhengcheng

2018-03-21

2,5-Di- tert-butyl-1,4-bis(2-methoxyethoxy)benzene (DBBB) is studied as a redox shuttle additive for overcharge protection for a 1.5 Ah graphite/C-LFP lithium-ion pouch cell for the first time. The electrochemical performance demonstrated that the protecting additive remains inert during the extended standard cycling for 4000 cycles. When a 100% overcharge is introduced in the charging protocol, the baseline cell fails rapidly during the first abusive event, whereas the cell containing DBBB additive withstands 700 overcharge cycles with 87% capacity retention and no gas evolution or cell swelling was observed. It is the first time the effectiveness of the DBBB as overcharge protection additive in a large pouch cell format is demonstrated.

Protective effects of antioxidin-RL from Odorrana livida against ultraviolet B-irradiated skin photoaging.

PubMed

Qin, Di; Lee, Wen-Hui; Gao, Zhiqin; Zhang, Weifen; Peng, Meiyu; Sun, Tongyi; Gao, Yuanyuan

2018-03-01

The unavoidable daily exposure of the skin to ultraviolet (UV) B radiation is proven to have deleterious effects. The action mechanism of antioxidin-RL, an antioxidant peptide purified from skin secretions of frog Odorrana livida with amino acid sequence of AMRLTYNRPCIYAT, is well characterized by NMR titration and mutation based on ABTS + scavenging activities. In order to explore the protective effects of antioxidin-RL against UVB-irradiated skin photoaging, cell uptake assay was used to detect the location of antioxidin-RL molecules serving various biological functions in the cells. The protective effects of antioxidin-RL on UVB-induced response were examined in vitro and in vivo. Results showed that antioxidin-RL successfully penetrated the cell membrane and exerted a positive effect on cell migration. It also effectively inhibited the UVB-induced excessive production of ROS and prevented oxidative damage to DNAs and proteins. Moreover, the mRNA expressions of MMP-1, VEGF, COX-2, and pro-inflammatory cytokines, such as IL-6 and TNF-α in antioxidin-RL-treated HaCaT and HSF cells were significantly down-regulated whereas those of FGF, procollagen type I and TGF-β1 up-regulated. Antioxidin-RL effectively prevented UVB-induced erythema on mouse skin, thereby inhibiting UVB-induced skin thickening and inflammation and increasing collagen deposition as demonstrated by in vivo experiments. Hence, the novel antioxidant peptide antioxidin-RL can effectively reduce UVB-induced skin reactions in vivo and in vitro, providing potential molecules against UVB-induced inflammation and photoaging. Copyright © 2018 Elsevier Inc. All rights reserved.

Short-term calorie and protein restriction provide partial protection from chemotoxicity but do not delay glioma progression

PubMed Central

Brandhorst, Sebastian; Wei, Min; Hwang, Saewon; Morgan, Todd E.; Longo, Valter D.

2013-01-01

Short-term starvation (STS) protects normal cells while simultaneously sensitizing malignant cells to high-dose chemotherapeutic drugs in mice and possibly patients. The fasting-dependent protection of normal cells and sensitization of malignant cells depends, in part, on reduced levels of insulin-like growth factor-1 (IGF-1) and glucose. Calorie restricted diets with defined macronutrient (carbohydrate, protein, fat) ratios were evaluated for the effects on stress sensitization markers and protection in mice treated with high-dose chemotherapy. We show that short-term CR significantly reduced both glucose and IGF-1 levels, but when specific macronutrient deficiencies were tested, only the complete lack of proteins reduced IGF-1 levels. Short-term 50% CR combined with either severe protein-deficiency or ketogenic diets improved chemotoxicity resistance similarly to the standard 50% CR, but did not result in the high protection caused by STS. Notably, a high protein diet reversed the beneficial effects of short-term CR. In a subcutaneous mouse model of glioma, feeding a low protein (4% calories from protein) diet for more than 20 days did not delay tumor progression once the tumor became palpable. Also, cycles of short-term (3 days) 50% CR did not augment the chemotherapy efficacy of cisplatin in a murine breast cancer model. These results indicate that the protection from chemotoxicity and retardation of the progression of certain tumors achieved with fasting is not obtained with short-term calorie and/or macronutrient restriction. PMID:23454633

Cinnamon polyphenols regulate S100ß, sirtuins, and neuroactive proteins in rat C6 glioma cells

USDA-ARS?s Scientific Manuscript database

Dietary polyphenols exert neuroprotective effects in a variety of brain disorders, including Alzheimer’s disease, ischemia/stroke, and Parkinson’s disease. The protective effects of polyphenols in the brain and in neural cell cultures have been established. The role of glial cells in providing prote...

Taurine Protects Mouse Spermatocytes from Ionizing Radiation-Induced Damage Through Activation of Nrf2/HO-1 Signaling.

PubMed

Yang, Wenjun; Huang, Jinfeng; Xiao, Bang; Liu, Yan; Zhu, Yiqing; Wang, Fang; Sun, Shuhan

2017-01-01

The increasing prevalence of ionizing radiation exposure has inevitably raised public concern over the potential detrimental effects of ionizing radiation on male reproductive system function. The detection of drug candidates to prevent reproductive system from damage caused by ionizing radiation is urgent. We aimed to investigate the protective role of taurine on the injury of mouse spermatocyte-derived cells (GC-2) subjected to ionizing radiation. mouse spermatocytes (GC-2 cells) were exposed to ionizing radiation with or without treatment of Taurine. The effect of ionizing radiation and Taurine treatment on GC-2 cells were evaluated by cell viability assay (CCK8), cell cycle and apoptosis. The relative protein abundance change was determined by Western blotting. The siRNA was used to explore whether Nrf2 signaling was involved in the cytoprotection of Taurine. Taurine significantly inhibited the decrease of cell viability, percentage of apoptotic cells and cell cycle arrest induced by ionizing radiation. Western blot analysis showed that taurine significantly limited the ionizing radiation-induced down-regulation of CyclinB1 and CDK1, and suppressed activation of Fas/FasL system pathway. In addition, taurine treatment significantly increased the expression of Nrf2 and HO-1 in GC-2 cells exposed to ionizing radiation, two components in antioxidant pathway. The above cytoprotection of Taurine was blocked by siNrf2. Our results demonstrate that taurine has the potential to effectively protect GC-2 cells from ionizing radiation- triggered damage via upregulation of Nrf2/HO-1 signaling. © 2017 The Author(s). Published by S. Karger AG, Basel.

Protection of Brain Injury by Amniotic Mesenchymal Stromal Cell-Secreted Metabolites.

PubMed

Pischiutta, Francesca; Brunelli, Laura; Romele, Pietro; Silini, Antonietta; Sammali, Eliana; Paracchini, Lara; Marchini, Sergio; Talamini, Laura; Bigini, Paolo; Boncoraglio, Giorgio B; Pastorelli, Roberta; De Simoni, Maria-Grazia; Parolini, Ornella; Zanier, Elisa R

2016-11-01

To define the features of human amniotic mesenchymal stromal cell secretome and its protective properties in experimental models of acute brain injury. Prospective experimental study. Laboratory research. C57Bl/6 mice. Mice subjected to sham or traumatic brain injury by controlled cortical impact received human amniotic mesenchymal stromal cells or phosphate-buffered saline infused intracerebroventricularly or intravenously 24 hours after injury. Organotypic cortical brain slices exposed to ischemic injury by oxygen-glucose deprivation were treated with human amniotic mesenchymal stromal cells or with their secretome (conditioned medium) in a transwell system. Traumatic brain injured mice receiving human amniotic mesenchymal stromal cells intravenously or intracerebroventricularly showed early and lasting functional and anatomical brain protection. cortical slices injured by oxigen-glucose deprivation and treated with human amniotic mesenchymal stromal cells or conditioned medium showed comparable protective effects (neuronal rescue, promotion of M2 microglia polarization, induction of trophic factors) indicating that the exposure of human amniotic mesenchymal stromal cells to the injured tissue is not necessary for the release of bioactive factors. Using sequential size-exclusion and gel-filtration chromatography, we identified a conditioned medium subfraction, which specifically displays these highly protective properties and we found that this fraction was rich in bioactive molecules with molecular weight smaller than 700 Da. Quantitative RNA analysis and mass spectrometry-based peptidomics showed that the active factors are not proteins or RNAs. The metabolomic profiling of six metabolic classes identified a list of molecules whose abundance was selectively elevated in the active conditioned medium fraction. Human amniotic mesenchymal stromal cell-secreted factors protect the brain after acute injury. Importantly, a fraction rich in metabolites, and containing neither proteic nor ribonucleic molecules was protective. This study indicates the profiling of protective factors that could be useful in cell-free therapeutic approaches for acute brain injury.

Trimetazidine protects against cardiac ischemia/reperfusion injury via effects on cardiac miRNA-21 expression, Akt and the Bcl-2/Bax pathway

PubMed Central

Ma, Ning; Bai, Jingyun; Zhang, Weihua; Luo, Hong; Zhang, Xin; Liu, Donghai; Qiao, Chenhui

2016-01-01

Trimetazidine is a piperazine-derived metabolic agent, which exerts cell protective effects and has been reported to be efficient in the treatment of chronic stable angina pectoris. In addition, it has been shown to exert protection against acute myocardial infarction. The present study aimed to investigate whether trimetazidine protects against cardiac ischemia/reperfusion (I/R) injury, and to determine whether its curative effects are associated with microRNA (miRNA)-21 expression, Akt, and the B-cell lymphoma 2 (Bcl-2)/Bcl-2-associated X protein (Bax) pathway. Cardiac I/R injury was induced by ligating the left anterior descending coronary artery in adult rats. Subsequently, cardiac function was evaluated, and the expression levels of miRNA-21, Bcl-2, Bax and phosphorylated-Akt were detected using quantitative polymerase chain reaction and western blotting. The results indicated that trimetazidine was able to significantly protect cardiac function and reduce infarct size in rats following cardiac I/R injury. Furthermore, trimetazidine significantly promoted miRNA-21 expression and phosphorylated-Akt protein expression, and reduced the Bcl-2/Bax ratio in rats following cardiac I/R injury. Knockdown of miRNA-21 using anti-miR-21 plasmids was able to reverse the protective effects of trimetazidine against cardiac I/R injury. These results indicated that miRNA-21 serves a protective role in cardiac I/R injury via Akt and the Bcl-2/Bax pathway. In addition, trimetazidine exerts protective effects against cardiac I/R injury through cardiac miRNA-21 expression, Akt, and the Bcl-2/Bax pathway. Therefore, the present study provided evidence regarding the protective effects of miRNA-21 on cardiac I/R injury following treatment with trimetazidine in vivo. PMID:27666568

Protective Role of Dietary Berries in Cancer

PubMed Central

Kristo, Aleksandra S.; Klimis-Zacas, Dorothy; Sikalidis, Angelos K.

2016-01-01

Dietary patterns, including regular consumption of particular foods such as berries as well as bioactive compounds, may confer specific molecular and cellular protection in addition to the overall epidemiologically observed benefits of plant food consumption (lower rates of obesity and chronic disease risk), further enhancing health. Mounting evidence reports a variety of health benefits of berry fruits that are usually attributed to their non-nutritive bioactive compounds, mainly phenolic substances such as flavonoids or anthocyanins. Although it is still unclear which particular constituents are responsible for the extended health benefits, it appears that whole berry consumption generally confers some anti-oxidant and anti-inflammatory protection to humans and animals. With regards to cancer, studies have reported beneficial effects of berries or their constituents including attenuation of inflammation, inhibition of angiogenesis, protection from DNA damage, as well as effects on apoptosis or proliferation rates of malignant cells. Berries extend effects on the proliferation rates of both premalignant and malignant cells. Their effect on premalignant cells is important for their ability to cause premalignant lesions to regress both in animals and in humans. The present review focuses primarily on in vivo and human dietary studies of various berry fruits and discusses whether regular dietary intake of berries can prevent cancer initiation and delay progression in humans or ameliorate patients’ cancer status. PMID:27775562

Protective Role of Dietary Berries in Cancer.

PubMed

Kristo, Aleksandra S; Klimis-Zacas, Dorothy; Sikalidis, Angelos K

2016-10-19

Dietary patterns, including regular consumption of particular foods such as berries as well as bioactive compounds, may confer specific molecular and cellular protection in addition to the overall epidemiologically observed benefits of plant food consumption (lower rates of obesity and chronic disease risk), further enhancing health. Mounting evidence reports a variety of health benefits of berry fruits that are usually attributed to their non-nutritive bioactive compounds, mainly phenolic substances such as flavonoids or anthocyanins. Although it is still unclear which particular constituents are responsible for the extended health benefits, it appears that whole berry consumption generally confers some anti-oxidant and anti-inflammatory protection to humans and animals. With regards to cancer, studies have reported beneficial effects of berries or their constituents including attenuation of inflammation, inhibition of angiogenesis, protection from DNA damage, as well as effects on apoptosis or proliferation rates of malignant cells. Berries extend effects on the proliferation rates of both premalignant and malignant cells. Their effect on premalignant cells is important for their ability to cause premalignant lesions to regress both in animals and in humans. The present review focuses primarily on in vivo and human dietary studies of various berry fruits and discusses whether regular dietary intake of berries can prevent cancer initiation and delay progression in humans or ameliorate patients' cancer status.

Acidic pre-conditioning suppresses apoptosis and increases expression of Bcl-xL in coronary endothelial cells under simulated ischaemia.

PubMed

Kumar, S; Reusch, H P; Ladilov, Y

2008-01-01

Ischaemic pre-conditioning has a powerful protective potential against ischaemia-induced cell death, and acidosis is an important feature of ischaemia and can lead to apoptosis. Here we tested whether pre-conditioning with acidosis, that is, acidic pre-conditioning (APC), may protect coronary endothelial cells (EC) against apoptosis induced by simulated ischaemia. For pre-conditioning, EC were exposed fo 40 min. to acidosis (pH 6.4) followed by a 14-hrs recovery period (pH 7.4) and finally treated for 2 hrs with simulated ischaemia (glucose-free anoxia at pH 6.4). Cells undergoing apoptosis were visualized by chromatin staining or by determination of caspase-3 activity Simulated ischaemia in untreated EC increased caspase-3 activity and the number of apoptotic cell (31.3 +/- 1.3%versus 3.9 +/- 0.6% in control). APC significantly reduced the rate of apoptosis (14.2 +/- 1.3%) and caspase-3 activity. Western blot analysis exploring the under lying mechanism leading to this protection revealed suppression of the endoplasmic reticulum- (reduced cleavage of caspase-12) and mitochondria-mediated (reduced cytochrome C release) pathways of apoptosis. These effects were associated with an over-expression of the anti-apoptotic protein Bcl-xL 14 hrs after APC, whereas no effect on the expression of Bcl-2, Bax, Bak, procaspase-12, reticulum-localized chaperones (GRP78, calreticulin), HSP70, HSP32 and HSP27 could be detected. Knock-down of Bcl-xL by siRNA-treatment prevented the protective effect of APC. In conclusion, short acidic pre-treatment can protect EC against ischaemic apoptosis. The mechanism of this protection consists of suppression of the endoplasmic reticulum- and mitochondria-mediated pathways. Over-expression of the anti apoptotic protein Bcl-xL is responsible for the increased resistance to apoptosis during ischaemic insult.

Microsomal Glutathione Transferase 1 Protects Against Toxicity Induced by Silica Nanoparticles but Not by Zinc Oxide Nanoparticles

PubMed Central

2012-01-01

Microsomal glutathione transferase 1 (MGST1) is an antioxidant enzyme located predominantly in the mitochondrial outer membrane and endoplasmic reticulum and has been shown to protect cells from lipid peroxidation induced by a variety of cytostatic drugs and pro-oxidant stimuli. We hypothesized that MGST1 may also protect against nanomaterial-induced cytotoxicity through a specific effect on lipid peroxidation. We evaluated the induction of cytotoxicity and oxidative stress by TiO2, CeO2, SiO2, and ZnO in the human MCF-7 cell line with or without overexpression of MGST1. SiO2 and ZnO nanoparticles caused dose- and time-dependent toxicity, whereas no obvious cytotoxic effects were induced by nanoparticles of TiO2 and CeO2. We also noted pronounced cytotoxicity for three out of four additional SiO2 nanoparticles tested. Overexpression of MGST1 reversed the cytotoxicity of the main SiO2 nanoparticles tested and for one of the supplementary SiO2 nanoparticles but did not protect cells against ZnO-induced cytotoxic effects. The data point toward a role of lipid peroxidation in SiO2 nanoparticle-induced cell death. For ZnO nanoparticles, rapid dissolution was observed, and the subsequent interaction of Zn2+ with cellular targets is likely to contribute to the cytotoxic effects. A direct inhibition of MGST1 by Zn2+ could provide a possible explanation for the lack of protection against ZnO nanoparticles in this model. Our data also showed that SiO2 nanoparticle-induced cytotoxicity is mitigated in the presence of serum, potentially through masking of reactive surface groups by serum proteins, whereas ZnO nanoparticles were cytotoxic both in the presence and in the absence of serum. PMID:22303956

Protective effects of 6-Gingerol on vascular endothelial cell injury induced by high glucose via activation of PI3K-AKT-eNOS pathway in human umbilical vein endothelial cells.

PubMed

Liu, Dan; Wu, Mengqing; Lu, Yi; Xian, Tao; Wang, Yupeng; Huang, Bowei; Zeng, Guohua; Huang, Qiren

2017-09-01

6-Gingerol (6-Gin), an active constituent of Zingiber officinale, has been reported to have anti-inflammatory, anti-oxidative, anti-cancerous etc. bioactivities. However, little is known about its endothelial protective effects and the underlying mechanisms. In this study, our purpose was to investigate the protective effects of 6-Gin and its underlying mechanisms. HUVECs were exposed to high glucose (HG, 33mM glucose) for 48h, followed by 50μM 6-Gin with or without LY294002 (10μM), AKT inhibitor IV (0.5μM) or L-NAME (5mM) for another 24h. Cell viability, levels of NO, LDH and ROS were detected. In addition, the expression levels of IKK, IRS-1, PI3K, AKT, eNOS and their phosphorylated proteins were measured by western blots. Compared with the control, HUVECs were significantly impaired by HG, characterized by decreased levels of the cell viability, NO, pY458-PI3K, pS473-AKT and pS1177-eNOS while increased levels of LDH, pS176-IKK, and p-S312-IRS-1. Conversely, 6-Gin remarkably protected HUVECs against HG-induced injury in a concentration- and time-dependent manner. However, the protective effects of 6-Gin were abolished by co-treatment with LY294002, AKT inhibitor IV or L-NAME at the HG state. Collectively, 6-Gin attenuated the injury of HUVECs induced by HG through the activation of PI3K-AKT-eNOS signal pathway. The findings provide a novel potential for 6-Gin to prevent and treat the angiopathy resulting from diabetes mellitus. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Gata3 hypermethylation and Foxp3 hypomethylation are associated with sustained protection and bystander effect following epicutaneous immunotherapy in peanut-sensitized mice.

PubMed

Mondoulet, Lucie; Dioszeghy, Vincent; Busato, Florence; Plaquet, Camille; Dhelft, Véronique; Bethune, Kevin; Leclere, Laurence; Daviaud, Christian; Ligouis, Mélanie; Sampson, Hugh; Dupont, Christophe; Tost, Jörg

2018-05-19

Epicutaneous immunotherapy (EPIT) is a promising method for treating food allergies. In animal models, EPIT induces sustained unresponsiveness and prevents further sensitization mediated by Tregs. Here, we elucidate the mechanisms underlying the therapeutic effect of EPIT, by characterizing the kinetics of DNA methylation changes in sorted cells from spleen and blood and by evaluating its persistence and bystander effect compared to oral immunotherapy (OIT). BALB/c mice orally sensitized to peanut proteins (PPE) were treated by EPIT using a PPE-patch or by PPE-OIT. Another set of peanut-sensitized mice treated by EPIT or OIT were sacrificed following a protocol of sensitization to OVA. DNA methylation was analysed during immunotherapy and 8 weeks after the end of treatment in sorted cells from spleen and blood by pyrosequencing. Humoral and cellular responses were measured during and after immunotherapy. Analyses showed a significant hypermethylation of the Gata3 promoter detectable only in Th2 cells for EPIT from the 4 th week and a significant hypomethylation of the Foxp3 promoter in CD62L + Tregs, which was sustained only for EPIT. In addition, mice treated with EPIT were protected from subsequent sensitization and maintained the epigenetic signature characteristic for EPIT. Our study demonstrates that EPIT leads to a unique and stable epigenetic signature in specific T cell compartments with down regulation of Th2 key regulators and upregulation of Treg transcription factors, likely explaining the sustainability of protection and the observed bystander effect. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

IGF-1 protects intestinal epithelial cells from oxidative stress-induced apoptosis.

PubMed

Baregamian, Naira; Song, Jun; Jeschke, Marc G; Evers, B Mark; Chung, Dai H

2006-11-01

Reactive oxygen species (ROS) are involved in the pathogenesis of necrotizing enterocolitis (NEC) in premature infants. We have recently found that activation of multiple cellular signaling transduction pathways occurs during ROS-induced intestinal cell apoptosis; the phosphatidylinositol 3-kinase (PI3-K) pathway plays an anti-apoptotic role during this process. Insulin-like growth factor (IGF)-1 activates PI3-K pathway to promote cell survival; however, the effects of IGF-1 treatment during gut injury are not clearly defined. The purpose of this study was to determine whether IGF-1 protects intestinal cells from ROS-induced apoptosis. Rat intestinal epithelial (RIE)-1 cells were treated with either IGF-1 (100 nm), hydrogen peroxide (H2O2; 500 microm), or combination. Western blotting was performed to assess phosphorylation of Akt, a downstream effector of PI3-K. Cell Death Detection ELISA, DCHF, and JC-1 assays were performed to demonstrate protective effects of IGF-1. Wortmannin, an inhibitor of PI3-K, was used to show PI3-K-dependent mechanism of action for IGF-1. H2O2 treatment resulted in increased intestinal epithelial cell apoptosis with intracellular ROS generation and mitochondrial membrane depolarization; IGF-1 pre-treatment attenuated this response without affecting ROS production. H2O2-induced phosphorylation of Akt was further increased with IGF-1 treatment; wortmannin abolished these effects in RIE-1 cells. PI3-K pathway is activated during ROS-induced intestinal epithelial cell injury; IGF-1 exerted an anti-apoptotic effect during this response by PI3-K activation. A better understanding of the exact role of IGF-1-mediated activation of PI3-K may allow us to facilitate the development of novel therapy against NEC.

Gut microbial metabolites limit the frequency of autoimmune T cells and protect against type 1 diabetes.

PubMed

Mariño, Eliana; Richards, James L; McLeod, Keiran H; Stanley, Dragana; Yap, Yu Anne; Knight, Jacinta; McKenzie, Craig; Kranich, Jan; Oliveira, Ana Carolina; Rossello, Fernando J; Krishnamurthy, Balasubramanian; Nefzger, Christian M; Macia, Laurence; Thorburn, Alison; Baxter, Alan G; Morahan, Grant; Wong, Lee H; Polo, Jose M; Moore, Robert J; Lockett, Trevor J; Clarke, Julie M; Topping, David L; Harrison, Leonard C; Mackay, Charles R

2017-05-01

Gut dysbiosis might underlie the pathogenesis of type 1 diabetes. In mice of the non-obese diabetic (NOD) strain, we found that key features of disease correlated inversely with blood and fecal concentrations of the microbial metabolites acetate and butyrate. We therefore fed NOD mice specialized diets designed to release large amounts of acetate or butyrate after bacterial fermentation in the colon. Each diet provided a high degree of protection from diabetes, even when administered after breakdown of immunotolerance. Feeding mice a combined acetate- and butyrate-yielding diet provided complete protection, which suggested that acetate and butyrate might operate through distinct mechanisms. Acetate markedly decreased the frequency of autoreactive T cells in lymphoid tissues, through effects on B cells and their ability to expand populations of autoreactive T cells. A diet containing butyrate boosted the number and function of regulatory T cells, whereas acetate- and butyrate-yielding diets enhanced gut integrity and decreased serum concentration of diabetogenic cytokines such as IL-21. Medicinal foods or metabolites might represent an effective and natural approach for countering the numerous immunological defects that contribute to T cell-dependent autoimmune diseases.

The protective effect of lipid emulsion in preventing bupivacaine-induced mitochondrial injury and apoptosis of H9C2 cardiomyocytes.

PubMed

Chen, Zhe; Jin, Zhousheng; Xia, Yun; Zhao, Shishi; Xu, Xuzhong; Papadimos, Thomas J; Wang, Quanguang

2017-11-01

Lipid emulsion (LE) has been shown to be effective in the resuscitation of bupivacaine-induced cardiac arrest, but the precise mechanism of this action has not been fully elucidated. Pursuant to this lack of information on the mechanism in which LE protects the myocardium during bupivacaine-induced toxicity, we explored mitochondrial function and cell apoptosis. H9C2 cardiomyocytes were used in study. Cells were randomly divided in different groups and were cultivated 6 h, 12 h, and 24 h. The mitochondria were extracted and mitochondrial ATP content was measured, as was mitochondrial membrane potential, the concentration of calcium ion (Ca2+), and the activity of Ca2+-ATP enzyme (Ca2+-ATPase). Cells from groups Bup1000, LE group, and Bup1000LE were collected to determine cell viability, cell apoptosis, and electron microscopy scanning of mitochondrial ultrastructure (after 24 h). We found that LE can reverse the inhibition of the mitochondrial function induced by bupivacaine, regulate the concentration of calcium ion in mitochondria, resulting in the protection of myocardial cells from toxicity induced by bupivacaine.

Frequent inoculations with radiation attenuated sporozoite is essential for inducing sterile protection that correlates with a threshold level of Plasmodia liver-stage specific CD8+ T cells.

PubMed

Patel, Hardik; Yadav, Naveen; Parmar, Rajesh; Patel, Satish; Singh, Agam P; Shrivastava, Neeta; Dalai, Sarat K

2017-07-01

Whole sporozoite vaccine (WSV) is shown to induce sterile protection that targets Plasmodium liver-stage infection. There are many underlying issues associated with induction of effective sterile protracted protection. In this study, we have addressed how the alterations in successive vaccine regimen could possibly affect the induction of sterile protection. We have demonstrated that the pattern of vaccination with RAS (radiation attenuated sporozoites) induces varying degrees of protection among B6 mice. Animals receiving four successive doses generated 100% sterile protection. However, three successive doses, though with the same parasite inoculum as four doses, could induce sterile protection in ∼50% mice. Interestingly, mice immunized with the same 3 doses, but with longer gap, could not survive the challenge. We demonstrate that degree of protection correlates with the frequencies of IFN-γ + and multifunctional (IFN-γ + CD107a + ) CD8 + T EM cells present in liver. The failure to achieve protective threshold frequency of these cells in liver might make the host more vulnerable to parasite infection during infectious sporozoite challenge. Copyright © 2017. Published by Elsevier Inc.

Inhibition of mTOR enhances radiosensitivity of lung cancer cells and protects normal lung cells against radiation.

PubMed

Zheng, Hang; Wang, Miao; Wu, Jing; Wang, Zhi-Ming; Nan, Hai-Jun; Sun, He

2016-06-01

Radiotherapy has been used for a long time as a standard therapy for cancer; however, there have been no recent research breakthroughs. Radioresistance and various side-effects lead to the unexpected outcomes of radiation therapy. Specific and accurate targeting as well as reduction of radioresistance have been major challenges for irradiation therapy. Recent studies have shown that rapamycin shows promise for inhibiting tumorigenesis by suppressing mammalian target of rapamycin (mTOR). We found that the combination of rapamycin with irradiation significantly diminished cell viability and colony formation, and increased cell apoptosis, as compared with irradiation alone in lung cancer cell line A549, suggesting that rapamycin can enhance the effectiveness of radiation therapy by sensitizing cancer cells to irradiation. Importantly, we observed that the adverse effects of irradiation on a healthy lung cell line (WI-38) were also offset. No enhanced protein expression of mTOR signaling was observed in WI-38 cells, which is normally elevated in lung cancer cells. Moreover, DNA damage was significantly less with the combination therapy than with irradiation therapy alone. Our data suggest that the incorporation of rapamycin during radiation therapy could be a potent way to improve the sensitivity and effectiveness of radiation therapy as well as to protect normal cells from being damaged by irradiation.

Fucoidan Does Not Exert Anti-Tumorigenic Effects on Uveal Melanoma Cell Lines

PubMed Central

Dithmer, Michaela; Kirsch, Anna-Maria; Richert, Elisabeth; Fuchs, Sabine; Wang, Fanlu; Schmidt, Harald; Coupland, Sarah E.; Roider, Johann; Klettner, Alexa

2017-01-01

Background. The polysaccharide fucoidan is widely investigated as an anti-cancer agent. Here, we tested the effect of fucoidan on uveal melanoma cell lines. Methods. The effect of 100 µM fucoidan was investigated on five cell lines (92.1, Mel270 OMM1, OMM2.3, OMM2.5) and of 1 µg/mL–1 mg/mL fucoidan in two cell lines (OMM1, OMM2.3). Cell proliferation and viability were investigated with a WST-1 assay, migration in a wound healing (scratch) assay. Vascular Endothelial Growth Factor (VEGF) was measured in ELISA. Angiogenesis was evaluated in co-cultures with endothelial cells. Cell toxicity was induced by hydrogen-peroxide. Protein expression (Akt, ERK1/2, Bcl-2, Bax) was investigated in Western blot. Results. Fucoidan increased proliferation in two and reduced it in one cell line. Migration was reduced in three cell lines. The effect of fucoidan on VEGF was cell type and concentration dependent. In endothelial co-culture with 92.1, fucoidan significantly increased tubular structures. Moreover, fucoidan significantly protected all tested uveal melanoma cell lines from hydrogen-peroxide induced cell death. Under oxidative stress, fucoidan did not alter the expression of Bcl-2, Bax or ERK1/2, while inducing Akt expression in 92.1 cells but not in any other cell line. Conclusion. Fucoidan did not show anti-tumorigenic effects but displayed protective and pro-angiogenic properties, rendering fucoidan unsuitable as a potential new drug for the treatment of uveal melanoma. PMID:28640204

Hydrogen Sulfide Inhibits Formaldehyde-Induced Endoplasmic Reticulum Stress in PC12 Cells by Upregulation of SIRT-1

PubMed Central

Zhang, Ping; Chen, Li-Xun; Wang, Li; Xie, Ming; Wang, Chun-Yan; Tang, Xiao-Qing

2014-01-01

Background Formaldehyde (FA), a well-known environmental pollutant, has been classified as a neurotoxic molecule. Our recent data demonstrate that hydrogen sulfide (H2S), the third gaseous transmitter, has a protective effect on the neurotoxicity of FA. However, the exact mechanisms underlying this protection remain largely unknown. Endoplasmic reticulum (ER) stress has been implicated in the neurotoxicity of FA. Silent mating type information regulator 2 homolog 1 (SIRT-1), a histone deacetylases, has various biological activities, including the extension of lifespan, the modulation of ER stress, and the neuroprotective action. Objective We hypothesize that the protection of H2S against FA-induced neurotoxicity involves in inhibiting ER stress by upregulation of SIRT-1. The present study attempted to investigate the protective effect of H2S on FA-induced ER stress in PC12 cells and the contribution of SIRT-1 to the protection of H2S against FA-induced injuries, including ER stress, cytotoxicity and apoptosis. Principal Findings We found that exogenous application of sodium hydrosulfide (NaHS; an H2S donor) significantly attenuated FA-induced ER stress responses, including the upregulated levels of glucose-regulated protein 78, C/EBP homologous protein, and cleaved caspase-12 expression. We showed that NaHS upregulates the expression of SIRT-1 in PC12 cells. Moreover, the protective effects of H2S on FA-elicited ER stress, cytotoxicity and apoptosis were reversed by Sirtinol, a specific inhibitor of SIRT-1. Conclusion/Significance These data indicate that H2S exerts its protection against the neurotoxicity of FA through overcoming ER stress via upregulation of SIRT-1. Our findings provide novel insights into the protective mechanisms of H2S against FA-induced neurotoxicity. PMID:24587076

Kefiran antagonizes cytopathic effects of Bacillus cereus extracellular factors.

PubMed

Medrano, Micaela; Pérez, Pablo Fernando; Abraham, Analía Graciela

2008-02-29

Kefiran, the polysaccharide produced by microorganisms present in kefir grains, is a water-soluble branched glucogalactan containing equal amounts of D-glucose and D-galactose. In this study, the effect of kefiran on the biological activity of Bacillus cereus strain B10502 extracellular factors was assessed by using cultured human enterocytes (Caco-2 cells) and human erythrocytes. In the presence of kefiran concentrations ranging from 300 to 1000 mg/L, the ability of B. cereus B10502 spent culture supernatants to detach and damage cultured human enterocytes was significantly abrogated. In addition, mitochondrial dehydrogenase activity was higher when kefiran was present during the cell toxicity assays. Protection was also demonstrated in hemolysis and apoptosis/necrosis assays. Scanning electron microscopy showed the protective effect of kefiran against structural cell damages produced by factors synthesized by B. cereus strain B10502. Protective effect of kefiran depended on strain of B. cereus. Our findings demonstrate the ability of kefiran to antagonize key events of B. cereus B10502 virulence. This property, although strain-specific, gives new perspectives for the role of bacterial exopolysaccharides in functional foods.

Involvement of the Nrf2-proteasome pathway in the endoplasmic reticulum stress response in pancreatic β-cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Sanghwan; Hur, Eu-gene; Ryoo, In-geun

2012-11-01

The ubiquitin-proteasome system plays a central role in protein quality control through endoplasmic reticulum (ER)-associated degradation (ERAD) of unfolded and misfolded proteins. NF-E2‐related factor 2 (Nrf2) is a transcription factor that controls the expression of an array of phase II detoxification and antioxidant genes. Nrf2 signaling has additionally been shown to upregulate the expression of the proteasome catalytic subunits in several cell types. Here, we investigated the role of Nrf2 in tunicamycin-induced ER stress using a murine insulinoma β-cell line, βTC-6. shRNA-mediated silencing of Nrf2 expression in βTC-6 cells significantly increased tunicamycin-induced cytotoxicity, elevated the expression of the pro-apoptotic ERmore » stress marker Chop10, and inhibited tunicamycin-inducible expression of the proteasomal catalytic subunits Psmb5 and Psmb6. The effects of 3H-1,2-dithiole-3-thione (D3T), a small molecule Nrf2 activator, on ER stress were also examined in βTC-6 cells. D3T pretreatment reduced tunicamycin cytotoxicity and attenuated the tunicamycin-inducible Chop10 and protein kinase RNA-activated‐like ER kinase (Perk). The protective effect of D3T was shown to be associated with increased ERAD. D3T increased the expression of Psmb5 and Psmb6 and elevated chymotrypsin-like peptidase activity; proteasome inhibitor treatment blocked D3T effects on tunicamycin cytotoxicity and ER stress marker changes. Similarly, silencing of Nrf2 abolished the protective effect of D3T against ER stress. These results indicate that the Nrf2 pathway contributes to the ER stress response in pancreatic β-cells by enhancing proteasome-mediated ERAD. -- Highlights: ► Nrf2 silencing in pancreatic β-cells enhanced tunicamycin-mediated ER stress. ► Expression of the proteasome was inducible by Nrf2 signaling. ► Nrf2 activator D3T protected β-cells from tunicamycin-mediated ER stress. ► Protective effect of D3T was associated with Nrf2-dependent proteasome induction.« less

rhEPO Enhances Cellular Anti-oxidant Capacity to Protect Long-Term Cultured Aging Primary Nerve Cells.

PubMed

Wang, Huqing; Fan, Jiaxin; Chen, Mengyi; Yao, Qingling; Gao, Zhen; Zhang, Guilian; Wu, Haiqin; Yu, Xiaorui

2017-08-01

Erythropoietin (EPO) may protect the nervous system of animals against aging damage, making it a potential anti-aging drug for the nervous system. However, experimental evidence from natural aging nerve cell models is lacking, and the efficacy of EPO and underlying mechanism of this effect warrant further study. Thus, the present study used long-term cultured primary nerve cells to successfully mimic the natural aging process of nerve cells. Starting on the 11th day of culture, cells were treated with different concentrations of recombinant human erythropoietin (rhEPO). Using double immunofluorescence labeling, we found that rhEPO significantly improved the morphology of long-term cultured primary nerve cells and increased the total number of long-term cultured primary cells. However, rhEPO did not improve the ratio of nerve cells. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to measure nerve cell activity and showed that rhEPO significantly improved the activity of long-term cultured primary nerve cells. Moreover, Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) double immunofluorescence labeling flow cytometry revealed that rhEPO reduced the apoptotic rate of long-term cultured primary nerve cells. Senescence-associated β-galactosidase (SA-β-gal) immunohistochemistry staining showed that rhEPO significantly reduced the aging rate of long-term cultured primary nerve cells. Immunochemistry revealed that rhEPO enhanced intracellular superoxide dismutase (SOD) activity and glutathione (GSH) abundance and reduced the intracellular malondialdehyde (MDA) level. In addition, this effect depended on the dose, was maximized at a dose of 100 U/ml and was more pronounced than that of vitamin E. In summary, this study finds that rhEPO protects long-term cultured primary nerve cells from aging in a dose-dependent manner. The mechanism of this effect may be associated with the enhancement of the intracellular anti-oxidant capacity. These findings provide a theoretical basis to further the anti-aging mechanism of EPO in the nervous system, and they provide experimental evidence at the cellular level for the clinical application of EPO to protect the nervous system from aging.

Berberine protects HK-2 cells from hypoxia/reoxygenation induced apoptosis via inhibiting SPHK1 expression.

PubMed

Lu, Jianrao; Yi, Yang; Pan, Ronghua; Zhang, Chuanfu; Han, Haiyan; Chen, Jie; Liu, Wenrui

2018-03-01

Renal ischemia reperfusion injury (RIRI) refers to the irreversible damage for renal function when blood perfusion is recovered after ischemia for an extended period, which is common in clinical surgeries and has been regarded as a major risk for acute renal failures (ARF) that is accompanied with unimaginably high morbidity and mortality. Hypoxia during ischemia followed by reoxygenation via reperfusion serves as a major event contributing to cell apoptosis, which has been widely accepted as the vital pathogenesis in RIRI. Preventing apoptosis in renal tubular epithelial cell has been considered as effective method for blocking RIRI. In this paper, we established a hypoxia/reoxygenation (H/R) injury model in human proximal tubular epithelial HK-2 cells. Here, we found increased SPHK1 levels in H/R injured HK-2 cells, which could be significantly down regulated after berberine treatment. Berberine has been reported to exert a protective effect on H/R-induced apoptosis of HK-2 cells. So, in our present study, we planned to investigate whether SPHK1 participated in the anti-apoptosis process of berberine in H/R injured HK-2 cells. Our study confirmed the protective effect of berberine against H/R-induced apoptosis in HK-2 cells through promoting cells viability, inhibiting cells apoptosis, and down-regulating p-P38, caspase-3, caspase-9 as well as SPHK1, while up regulating the ratio of Bcl-2/Bax. However, SPHK1 overexpression in HK-2 cells induced severe apoptosis, which can be significantly ameliorated with additional berberine treatment. We concluded that berberine could remarkably prevent H/R-induced apoptosis in HK-2 cells through down-regulating SPHK1 expression levels, and the mechanisms included the suppression of p38 MAPK activation and mitochondrial stress pathways.

Sickle Cell Trait and Fatal Exertional Heat Illness: Implications for Exercise-Related Death of Young Ddults

DTIC Science & Technology

2008-10-22

athletes who utilize ordinary weather reports? Alpha- Thalassemia Protects Against Exertional Mortality with Sickle Cell Trait • 30% of African...Americans have alpha- thalassemia (2-3 alpha genes instead of 4). In those with sickle cell trait the main effect is to lower the Hb S fraction below 36...expected 15 cases with alpha- thalassemia & ប% S • Two cases had Hb S < 36% , implying about a 7.5-fold protection for those with alpha thalassemia

Edaravone protects the retina against ischemia/reperfusion‑induced oxidative injury through the PI3K/Akt/Nrf2 pathway.

PubMed

Xu, Yi-Pin; Han, Fang; Tan, Jian

2017-12-01

Retinal ischemia/reperfusion (I/R) injury can occur as a result of a number of ocular diseases or ischemic events in the brain, leading to possible vision loss if not treated properly. The overproduction of reactive oxygen species is important in the process of I/R injury. Edaravone, a free radical scavenger, has been demonstrated to have a neuroprotective effect in cerebral ischemia; however, its effect against retinal I/R injury remains to be fully elucidated. Therefore, the present study investigated the effects of edaravone on the oxidative parameters, retinal inflammation and apoptosis induced by I/R injury, and treated photoreceptor‑derived 661W cells with hydrogen peroxide (H2O2) and edaravone to examine the underlying mechanism. For the in vivo study, oxidative parameters (malondialdehyde, DNA fragmentation, total antioxidant status, superoxide dismutase and glutathione) in the retina, retinal thickness, and apoptotic index in the ganglionic cell layer and inner nuclear layer were measured. For the in vitro study, the effects of edaravone or nuclear factor erythroid‑2‑related factor 2 (Nrf2) small interfering RNA or phosphatidylinositol 3‑kinase (PI3K)/Akt inhibitors on cell viability, membrane integrity, levels of phosphorylated‑Akt, Akt and nuclear Nrf2 of H2O2‑treated 661W cells were examined. The results demonstrated that edaravone inhibited the oxidative injury in the retina induced by the retinal I/R procedure and increased retinal inflammation, and apoptosis. The results of the in vitro experiments demonstrated that edaravone effectively protected the viability and the membrane integrity of the H2O2‑treated 661W cells via the phosphatidylinositol 3‑kinase (PI3K)/Akt/Nrf2pathway. These results indicated the potential protective effect of edaravone against retinal I/R injury and provided a novel explanation for the protective effects of edaravone.

Aqueous extract of Crataegus azarolus protects against DNA damage in human lymphoblast Cell K562 and enhances antioxidant activity.

PubMed

Mustapha, Nadia; Bouhlel, Inès; Chaabane, Fadwa; Bzéouich, Imèn Mokdad; Ghedira, Kamel; Hennebelle, Thierry; Chekir-Ghedira, Leila

2014-02-01

The present study was carried out to characterize the cellular antioxidant effect of the aqueous extract of Crataegus azarolus and its antigenotoxic potential using human myelogenous cells, K562. The antioxidant capacity of this extract was evaluated by determining its cellular antioxidant activity (CAA) in K562 cells. Also, preceding antigenotoxicity assessment, its eventual genotoxicity property was investigated by evaluating its capacity to induce the DNA degradation of treated cell nuclei. As no genotoxicity was detected at different exposure times, its ability to protect cell DNA against H2O2 oxidative effect was investigated, using the "comet assay." It appears that 800 μg/mL of extract inhibited the genotoxicity induced by H2O2 with a rate of 41.30 %, after 4 h of incubation. In addition, this extract revealed a significant cellular antioxidant capacity against the reactive oxygen species in K562 cells.