WorldWideScience

Sample records for attenuates microglial activation

  1. Brilliant blue G attenuates lipopolysaccharidemediated microglial activation and inflammation

    Institute of Scientific and Technical Information of China (English)

    Kui Lu; Jue Wang; Bin Hu; Xiaolei Shi; Junyi Zhou; Yamei Tang; Ying Peng

    2013-01-01

    Previous studies have confirmed that oxidized adenosine triphosphate, a P2X7 receptor antagonist, attenuates lipopolysaccharide-mediated microglial activation and inflammatory expression following neuronal damage in rat brain. NaCl and temperature may affect the potency of oxidized adenosine triphosphate. Brilliant blue G is a derivative of a widely used food additive and has little toxicity. This study explored the effects of brilliant blue G, a selective P2X7 receptor antagonist, on microglial activation and inflammation. Results demonstrated that brilliant blue G inhibited the release of cyclooxygenase-2 and interleukin-6 in BV2 cells. Immunofluorescence displayed that brilliant blue G could suppress lipopolysaccharide-induced microglial activation. This study used RNA interference to block P2X7 receptor expression and found that small interfering RNA also suppressed the release of cyclooxygenase-2 and interleukin-6 in BV2 cells. These results suggested that downregulation of the P2X7 receptor by brilliant blue G was involved in the inhibition of microglial activation and inflammation.

  2. Paeonol attenuates inflammation-mediated neurotoxicity and microglial activation

    Institute of Scientific and Technical Information of China (English)

    Kyong Nyon Nam; Byung-Cheol Woo; Sang-Kwan Moon; Seong-Uk Park; Joo-young Park; Jae-Woong Hwang; Hyung-Sup Bae; Chang-Nam Ko; Eunjoo Hwang Lee

    2013-01-01

    Chronic activation of microglial cells endangers neuronal survival through the release of various proinflammatory and neurotoxic factors. The root of Paeonia lactiflora Pall has been considered useful for the treatment of various disorders in traditional oriental medicine. Paeonol, found in the root of Paeonia lactiflora Pall, has a wide range of pharmacological functions, including anti-oxidative, anti-inflammatory and neuroprotective activities. The objective of this study was to examine the efficacy of paeonol in the repression of inflammation-induced neurotoxicity and microglial cell activation. Organotypic hippocampal slice cultures and primary microglial cells from rat brain were stimulated with bacterial lipopolysaccharide. Paeonol pretreatment was performed for 30 minutes prior to lipopolysaccharide addition. Cell viability and nitrite (the production of nitric oxide), tumor necrosis factor-alpha and interleukin-1beta products were measured after lipopolysaccharide treatment. In organotypic hippocampal slice cultures, paeonol blocked lipopolysaccharide-related hippocampal cell death and inhibited the release of nitrite and interleukin-1beta. Paeonol was effective in inhibiting nitric oxide release from primary microglial cells. It also reduced the lipopolysaccharide-stimulated release of tumor necrosis factor-alpha and interleukin-1β from microglial cells. Paeonol possesses neuroprotective activity in a model of inflammation-induced neurotoxicity and reduces the release of neurotoxic and proinflammatory factors in activated microglial cells.

  3. Activation of serotonin receptors promotes microglial injury-induced motility but attenuates phagocytic activity

    NARCIS (Netherlands)

    Krabbe, Grietje; Matyash, Vitali; Pannasch, Ulrike; Mamer, Lauren; Boddeke, Hendrikus W. G. M.; Kettenmann, Helmut

    2012-01-01

    Microglia, the brain immune cell, express several neurotransmitter receptors which modulate microglial functions. In this project we studied the impact of serotonin receptor activation on distinct microglial properties as serotonin deficiency not only has been linked to a number of psychiatric disea

  4. Caspase Inhibitors may Attenuate Opioid-induced Hyperalgesia and Tolerance via Inhibiting Microglial Activation and Neuroinflammation

    Directory of Open Access Journals (Sweden)

    Jiancheng Zhang

    2013-07-01

    Full Text Available Prolonged exposure to an opioid induces hyperalgesia and tolerance, which negatively affect pain management in turn and significantly hamper the application of opioids. A growing body of evidence has demonstrated that glial activation contributes to the development of these two side effects. Recent studies have demonstrated that morphine, binding to an accessory protein of Toll-like receptor 4 (TLR4, activates microglia and produces neuroinflammation in amanner parallel to lipopolysaccharide. Meanwhile, lipopolysaccharide activates microglia through TLR4/caspase signalling. Therefore, we hypothesise that morphine may activate microglia throughTLR4/caspase signalling and that caspase inhibitors may attenuate opioid-induced hyperalgesia and tolerance via inhibiting microglial activation and neuroinflammation

  5. Intrathecal lidocaine pretreatment attenuates immediate neuropathic pain by modulating Nav1.3 expression and decreasing spinal microglial activation

    Directory of Open Access Journals (Sweden)

    Wang Hung-Chen

    2011-06-01

    Full Text Available Abstract Background Intrathecal lidocaine reverses tactile allodynia after nerve injury, but whether neuropathic pain is attenuated by intrathecal lidocaine pretreatment is uncertain. Methods Sixty six adult male Sprague-Dawley rats were divided into three treatment groups: (1 sham (Group S, which underwent removal of the L6 transverse process; (2 ligated (Group L, which underwent left L5 spinal nerve ligation (SNL; and (3 pretreated (Group P, which underwent L5 SNL and was pretreated with intrathecal 2% lidocaine (50 μl. Neuropathic pain was assessed based on behavioral responses to thermal and mechanical stimuli. Expression of sodium channels (Nav1.3 and Nav1.8 in injured dorsal root ganglia and microglial proliferation/activation in the spinal cord were measured on post-operative days 3 (POD3 and 7 (POD7. Results Group L presented abnormal behavioral responses indicative of mechanical allodynia and thermal hyperalgesia, exhibited up-regulation of Nav1.3 and down-regulation of Nav1.8, and showed increased microglial activation. Compared with ligation only, pretreatment with intrathecal lidocaine before nerve injury (Group P, as measured on POD3, palliated both mechanical allodynia (p p 1.3 up-regulation (p = 0.003, and mitigated spinal microglial activation (p = 0.026 by inhibiting phosphorylation (activation of p38 MAP kinase (p = 0.034. p38 activation was also suppressed on POD7 (p = 0.002. Conclusions Intrathecal lidocaine prior to SNL blunts the response to noxious stimuli by attenuating Nav1.3 up-regulation and suppressing activation of spinal microglia. Although its effects are limited to 3 days, intrathecal lidocaine pretreatment can alleviate acute SNL-induced neuropathic pain.

  6. Modulation of microglial/macrophage activation by macrophage inhibitory factor (TKP or tuftsin (TKPR attenuates the disease course of experimental autoimmune encephalomyelitis

    Directory of Open Access Journals (Sweden)

    Tsirka Stella E

    2007-07-01

    Full Text Available Abstract Background Myelin Oligodendrocyte Glycoprotein (MOG-induced experimental autoimmune encephalomyelitis (EAE is the most commonly used mouse model for multiple sclerosis (MS. During the of progression of EAE, microglia, the immunocompetent cells of the brain, become activated and accumulate around demyelinated lesions. Microglial activation is mediated by the extracellular protease tissue Plasminogen Activator (tPA, and mice lacking tPA display altered EAE progression. In this study, we have used pharmacological inhibitors and stimulators of microglial/macrophage activation to examine the temporal requirement for microglial activation in EAE progression and to determine whether such approaches might potentially be of therapeutic value. Results Intervention using the tripeptide macrophage/microglia inhibitory factor MIF (TKP and the tetrapeptide macrophage/microglial stimulator tuftsin (TKPR attenuated EAE symptoms and revealed that the timing of macrophage/microglial activation is critical for the clinical outcome of EAE. We show that the disease progression can potentially be manipulated favorably at early stages by altering the timing of microglial activation, which in turn alters the systemic immune response to favor upregulation of T helper cell 2 genes that promote recovery from EAE. Conclusion Preventative and therapeutic modulation of macrophage/microglial activity significantly alters the outcome of EAE at symptomatic stages. Specific molecular targets have been identified that represent potential avenues of exploration for the treatment and prevention of MS.

  7. Intravenous multipotent adult progenitor cell therapy attenuates activated microglial/macrophage response and improves spatial learning after traumatic brain injury.

    Science.gov (United States)

    Bedi, Supinder S; Hetz, Robert; Thomas, Chelsea; Smith, Philippa; Olsen, Alex B; Williams, Stephen; Xue, Hasen; Aroom, Kevin; Uray, Karen; Hamilton, Jason; Mays, Robert W; Cox, Charles S

    2013-12-01

    We previously demonstrated that the intravenous delivery of multipotent adult progenitor cells (MAPCs) after traumatic brain injury (TBI) in rodents provides neuroprotection by preserving the blood-brain barrier and systemically attenuating inflammation in the acute time frame following cell treatment; however, the long-term behavioral and anti-inflammatory effects of MAPC administration after TBI have yet to be explored. We hypothesized that the intravenous injection of MAPCs after TBI attenuates the inflammatory response (as measured by microglial morphology) and improves performance at motor tasks and spatial learning (Morris water maze [MWM]). MAPCs were administered intravenously 2 and 24 hours after a cortical contusion injury (CCI). We tested four groups at 120 days after TBI: sham (uninjured), injured but not treated (CCI), and injured and treated with one of two concentrations of MAPCs, either 2 million cells per kilogram (CCI-2) or 10 million cells per kilogram (CCI-10). CCI-10 rats showed significant improvement in left hind limb deficit on the balance beam. On the fifth day of MWM trials, CCI-10 animals showed a significant decrease in both latency to platform and distance traveled compared with CCI. Probe trials revealed a significant decrease in proximity measure in CCI-10 compared with CCI, suggesting improved memory retrieval. Neuroinflammation was quantified by enumerating activated microglia in the ipsilateral hippocampus. We observed a significant decrease in the number of activated microglia in the dentate gyrus in CCI-10 compared with CCI. Our results demonstrate that intravenous MAPC treatment after TBI in a rodent model offers long-term improvements in spatial learning as well as attenuation of neuroinflammation.

  8. Electroacupuncture pretreatment prevents cognitive impairment induced by limb ischemia-reperfusion via inhibition of microglial activation and attenuation of oxidative stress in rats.

    Science.gov (United States)

    Chen, Ye; Zhou, Jun; Li, Jun; Yang, Shi-Bin; Mo, Li-Qun; Hu, Jie-Hui; Yuan, Wan-Li

    2012-01-13

    Limb ischemia-reperfusion (LI/R) is associated with high morbidity and mortality. Furthermore, critical trauma survivors can present cognitive impairment. Cognitive function, survival rate, oxidative stress and neuronal health were examined to elucidate (1) the magnitude of cognitive effects of prolonged reperfusion, (2) potential players in the mechanistic pathway mediating such effects, and (3) possible benefits of electroacupuncture (EA) pretreatment at Baihui (GV20), Yanglingquan (GB34), Taichong (LR3), Zusanli (ST36) and Xuehai (SP10) acupoints. LI/R was induced in rats by placing a rubber tourniquet on each hind limb for 3h, and the animals were evaluated periodically for 7d after LI/R. Rats subjected to LI/R had significantly lower survival rates, and displayed evidence of brain injury and cognitive dysfunction (as determined by the Morris water maze test) 1d and 3d after reperfusion compared to sham-operated controls. LI/R also resulted in higher levels of reactive oxygen species (ROS) and malondialdehyde (MDA), microglial activation, and decreased superoxide dismutase (SOD) activity within Cornu Ammonis area 1 (CA1) of the hippocampus. Depressed survival rates, microglial activation, oxidative damage, and histological changes, as well as cognitive dysfunction were partially or fully attenuated in rats that received 14d of EA prior to LI/R. These findings indicate that LI/R can result in cognitive dysfunction related to activated microglia and elevated oxidative stress, and that EA has neuroprotective potential mediated, at least in part, by inhibition of microglial activation and attenuation of oxidative stress. PMID:22129788

  9. Gypenoside Attenuates β Amyloid-Induced Inflammation in N9 Microglial Cells via SOCS1 Signaling

    Directory of Open Access Journals (Sweden)

    Hui Cai

    2016-01-01

    Full Text Available Reducing β amyloid- (Aβ- induced microglial activation is believed to be effective in treating Alzheimer’s disease (AD. Microglia can be activated into classic activated state (M1 state or alternative activated state (M2 state, and the former is harmful; in contrast, the latter is beneficial. Gypenoside (GP is the major bioactive constituent of Gynostemma pentaphyllum, a traditional Chinese herb medicine. In this study, we hypothesized that GP attenuates Aβ-induced microglial activation by ameliorating microglial M1/M2 states, and the process may be mediated by suppressor of cell signaling protein 1 (SOCS1. In this study, we found that Aβ exposure increased the levels of microglial M1 markers, including iNOS expression, tumor necrosis factor α (TNF-α, interleukin 1β (IL-1β, and IL-6 releases, and coadministration of GP reversed the increase of M1 markers and enhanced the levels of M2 markers, including arginase-1 (Arg-1 expression, IL-10, brain-derived neurotrophic factor (BDNF, and glial cell-derived neurotrophic factor (GDNF releases in the Aβ-treated microglial cells. SOCS1-siRNA, however, significantly abolished the GP-induced effects on the levels of microglial M1 and M2 markers. These findings indicated that GP attenuates Aβ-induced microglial activation by ameliorating M1/M2 states, and the process may be mediated by SOCS1.

  10. Microglial control of neuronal activity

    Directory of Open Access Journals (Sweden)

    Catherine eBéchade

    2013-03-01

    Full Text Available Fine-tuning of neuronal activity was thought to be a neuron-autonomous mechanism until the discovery that astrocytes are active players of synaptic transmission. The involvement of astrocytes has changed our understanding of the roles of non-neuronal cells and shed new light on the regulation of neuronal activity. Microglial cells are the macrophages of the brain and they have been mostly investigated as immune cells. However recent data discussed in this review support the notion that, similarly to astrocytes, microglia are involved in the regulation of neuronal activity. For instance, in most, if not all, brain pathologies a strong temporal correlation has long been known to exist between the pathological activation of microglia and dysfunction of neuronal activity. Recent studies have convincingly shown that alteration of microglial function is responsible for pathological neuronal activity. This causal relationship has also been demonstrated in mice bearing loss-of-function mutations in genes specifically expressed by microglia. In addition to these long-term regulations of neuronal activity, recent data show that microglia can also rapidly regulate neuronal activity, thereby acting as partners of neurotransmission.

  11. Stimulation of cannabinoid receptor 2 (CB2 suppresses microglial activation

    Directory of Open Access Journals (Sweden)

    Fernandez Francisco

    2005-12-01

    Full Text Available Abstract Background Activated microglial cells have been implicated in a number of neurodegenerative disorders, including Alzheimer's disease (AD, multiple sclerosis (MS, and HIV dementia. It is well known that inflammatory mediators such as nitric oxide (NO, cytokines, and chemokines play an important role in microglial cell-associated neuron cell damage. Our previous studies have shown that CD40 signaling is involved in pathological activation of microglial cells. Many data reveal that cannabinoids mediate suppression of inflammation in vitro and in vivo through stimulation of cannabinoid receptor 2 (CB2. Methods In this study, we investigated the effects of a cannabinoid agonist on CD40 expression and function by cultured microglial cells activated by IFN-γ using RT-PCR, Western immunoblotting, flow cytometry, and anti-CB2 small interfering RNA (siRNA analyses. Furthermore, we examined if the stimulation of CB2 could modulate the capacity of microglial cells to phagocytise Aβ1–42 peptide using a phagocytosis assay. Results We found that the selective stimulation of cannabinoid receptor CB2 by JWH-015 suppressed IFN-γ-induced CD40 expression. In addition, this CB2 agonist markedly inhibited IFN-γ-induced phosphorylation of JAK/STAT1. Further, this stimulation was also able to suppress microglial TNF-α and nitric oxide production induced either by IFN-γ or Aβ peptide challenge in the presence of CD40 ligation. Finally, we showed that CB2 activation by JWH-015 markedly attenuated CD40-mediated inhibition of microglial phagocytosis of Aβ1–42 peptide. Taken together, these results provide mechanistic insight into beneficial effects provided by cannabinoid receptor CB2 modulation in neurodegenerative diseases, particularly AD.

  12. Microglial activation - tuning and pruning adult neurogenesis

    Directory of Open Access Journals (Sweden)

    Christine T eEkdahl

    2012-03-01

    Full Text Available Adult born neurons are encountering numerous choices during their development from neural stem cells to mature functionally integrated neurons in the brain. Microglia are part of the microenvironment within the neurogenic niches and possibly involved during the entire decision process. Mounting evidence suggest that microglia act as local equalizers capable of amplifying as well as filtering homeostatic signals. Depending on their state of activation, they may induce or facilitate different fundamental decisions in neurogenesis, such as proliferation or quiescence, cell survival or death, migration or establishment, growth or retraction of dendrites and axons, synaptic assembly or pruning, or tuning of synaptic transmission. Microglia are activated as a first line of defence against infections and participate in transforming the innate immunity into an adaptive immune response by recruiting systemic immune cells. So far, most studies have reported an acute decrease in the survival of new neurons following this classically activated microglial reaction. However, the long-term effects are more complex. In several neurodegenerative diseases the microglial activation is also evident, including a heterogeneous population of microglial phenotypes and a plethora of immune mediators, where the initiating agent may be protein deposits or cell debris. The transformation from a pro- to an anti-inflammatory cytokine profile and the de-activation of microglia is not clearly defined, or even dysregulated, and the adaptive response is often sparse. The diverse role of microglial activation in neurodegenerative diseases is reflected by the numerous studies reporting both beneficial and detrimental effects on the different steps of neurogenesis. This review will highlight the most recent findings on how microglial activation modulates adult neurogenesis, and specifically discuss the role of microglia in synaptic integration, currently a fast expanding research

  13. Vitamin E Suppression of Microglial Activation Is Neuroprotective

    OpenAIRE

    Li, Yuekui; Liu, Ling; Barger, Steven W.; Mrak, Robert E; Griffin, W Sue T

    2001-01-01

    Neurotoxic microglial-neuronal interactions have been implicated in the pathogenesis of various neurodegenerative diseases such as Alzheimer’s disease, and vitamin E has been shown to have direct neuroprotective effects. To determine whether vitamin E also has indirect neuroprotective effects through suppression of microglial activation, we used a microglial-neuronal coculture. Lipopolysaccharide (LPS) treatment of a microglial cell line (N9) induced a time-dependent activation of both p38 mi...

  14. Aspirin-triggered lipoxin A4 attenuates LPS-induced pro-inflammatory responses by inhibiting activation of NF-κB and MAPKs in BV-2 microglial cells

    OpenAIRE

    Yuan Shi-Ying; Zhou Jie-Ping; Liu Ren-Gang; Zheng Jin; Li Long-Yan; Wu Yan; Wang Yan-Ping; Shang You; Yao Shang-Long

    2011-01-01

    Abstract Background Microglial activation plays an important role in neurodegenerative diseases through production of nitric oxide (NO) and several pro-inflammatory cytokines. Lipoxins (LXs) and aspirin-triggered LXs (ATLs) are considered to act as 'braking signals' in inflammation. In the present study, we investigated the effect of aspirin-triggered LXA4 (ATL) on infiammatory responses induced by lipopolysaccharide (LPS) in murine microglial BV-2 cells. Methods BV-2 cells were treated with ...

  15. Minocycline and sulforaphane inhibited lipopolysaccharide-mediated retinal microglial activation

    OpenAIRE

    Li-ping YANG; Zhu, Xiu-an; Tso, Mark O.M.

    2007-01-01

    Purpose To elucidate the inhibitory effect of minocycline and sulforaphane on lipopolysaccharide (LPS)-induced retinal microglial activation and the mechanisms through which they exerted their inhibitory effects. Methods Primary retinal microglial cultures were exposed to LPS with or without minocycline and sulforaphane. The mRNA expression of monocyte chemotactic protein (MCP)-1, MCP-3, macrophage inflammatory protein (MIP)-1α, MIP-1β, eotaxin, regulated upon activation normal T-cell express...

  16. Insensitivity of astrocytes to interleukin 10 signaling following peripheral immune challenge results in prolonged microglial activation in the aged brain.

    Science.gov (United States)

    Norden, Diana M; Trojanowski, Paige J; Walker, Frederick R; Godbout, Jonathan P

    2016-08-01

    Immune-activated microglia from aged mice produce exaggerated levels of cytokines. Despite high levels of microglial interleukin (IL)-10 in the aged brain, neuroinflammation was prolonged and associated with depressive-like deficits. Because astrocytes respond to IL-10 and, in turn, attenuate microglial activation, we investigated if astrocyte-mediated resolution of microglial activation was impaired with age. Here, aged astrocytes had a dysfunctional profile with higher glial fibrillary acidic protein, lower glutamate transporter expression, and significant cytoskeletal re-arrangement. Moreover, aged astrocytes had reduced expression of growth factors and IL-10 receptor-1 (IL-10R1). After in vivo lipopolysaccharide immune challenge, aged astrocytes had a molecular signature associated with reduced responsiveness to IL-10. This IL-10 insensitivity of aged astrocytes resulted in a failure to induce IL-10R1 and transforming growth factor β and resolve microglial activation. In addition, adult astrocytes reduced microglial activation when co-cultured ex vivo, whereas aged astrocytes did not. Consistent with the aging studies, IL-10R(KO) astrocytes did not augment transforming growth factor β after immune challenge and failed to resolve microglial activation. Collectively, a major cytokine-regulatory loop between activated microglia and astrocytes is impaired in the aged brain. PMID:27318131

  17. Inhibition of mammalian target of rapamycin attenuates early brain injury through modulating microglial polarization after experimental subarachnoid hemorrhage in rats.

    Science.gov (United States)

    You, Wanchun; Wang, Zhong; Li, Haiying; Shen, Haitao; Xu, Xiang; Jia, Genlai; Chen, Gang

    2016-08-15

    Here, we aimed to study the role and underlying mechanism of mTOR in early brain injury (EBI) after subarachnoid hemorrhage (SAH). Experiment 1, the time course of mTOR activation in the cortex following SAH. Experiment 2, the role of mTOR in SAH-induced EBI. Adult SD rats were divided into four groups: sham group (n=18), SAH+vehicle group (n=18), SAH+rapamycin group (n=18), SAH+AZD8055 group (n=18). Experiment 3, we incubated enriched microglia with OxyHb. Rapamycin and AZD8055 were also used to demonstrate the mTOR's role on microglial polarization in vitro. The phosphorylation levels of mTOR and its substrates were significantly increased and peaked at 24h after SAH. Rapamycin or AZD8055 markedly decreased the phosphorylation levels of mTOR and its substrates and the activation of microglia in vivo, and promoted the microglial polarization from M1 phenotype to M2 phenotype. In addition, administration of rapamycin and AZD8055 following SAH significantly ameliorated EBI, including neuronal apoptosis, neuronal necrosis, brain edema and blood-brain barrier permeability. Our findings suggested that the rapamycin and AZD8055 could attenuate the development of EBI in this SAH model, possibly through inhibiting the activation of microglia by mTOR pathway. PMID:27423593

  18. Magnolia polyphenols attenuate oxidative and inflammatory responses in neurons and microglial cells

    Directory of Open Access Journals (Sweden)

    Chuang Dennis Y

    2013-01-01

    Full Text Available Abstract Background The bark of magnolia has been used in Oriental medicine to treat a variety of remedies, including some neurological disorders. Magnolol (Mag and honokiol (Hon are isomers of polyphenolic compounds from the bark of Magnolia officinalis, and have been identified as major active components exhibiting anti-oxidative, anti-inflammatory, and neuroprotective effects. In this study, we investigate the ability of these isomers to suppress oxidative stress in neurons stimulated by the ionotropic glutamate receptor agonist N-methyl-D-aspartate (NMDA and oxidative and inflammatory responses in microglial cells activated by interferon-γ (IFNγ and lipopolysaccharide (LPS. We also attempt to elucidate the mechanism and signaling pathways involved in cytokine-induced production of reactive oxygen species (ROS in microglial cells. Methods Dihydroethidium (DHE was used to assay superoxide production in neurons, while CM-H2DCF-DA was used to test for ROS production in murine (BV-2 and rat (HAPI immortalized microglial cells. NADPH oxidase inhibitors (for example, diphenyleneiodonium (DPI, AEBSF, and apocynin and immunocytochemistry targeting p47phox and gp91phox were used to assess the involvement of NADPH oxidase. Western blotting was used to assess iNOS and ERK1/2 expression, and the Griess reaction protocol was employed to determine nitric oxide (NO concentration. Results Exposure of Hon and Mag (1–10 μM to neurons for 24 h did not alter neuronal viability, but both compounds (10 μM inhibited NMDA-stimulated superoxide production, a pathway known to involve NADPH oxidase. In microglial cells, Hon and Mag inhibited IFNγ±LPS-induced iNOS expression, NO, and ROS production. Studies with inhibitors and immunocytochemical assay further demonstrated the important role of IFNγ activating the NADPH oxidase through the p-ERK-dependent pathway. Hon and, to a lesser extent, Mag inhibited IFNγ-induced p-ERK1/2 and its downstream pathway for

  19. HIV-1 Tat protein increases microglial outward K(+ current and resultant neurotoxic activity.

    Directory of Open Access Journals (Sweden)

    Jianuo Liu

    Full Text Available Microglia plays a crucial role in the pathogenesis of HIV-1-associated neurocognitive disorders. Increasing evidence indicates the voltage-gated potassium (Kv channels are involved in the regulation of microglia function, prompting us to hypothesize Kv channels may also be involved in microglia-mediated neurotoxic activity in HIV-1-infected brain. To test this hypothesis, we investigated the involvement of Kv channels in the response of microglia to HIV-1 Tat protein. Treatment of rat microglia with HIV-1 Tat protein (200 ng/ml resulted in pro-inflammatory microglial activation, as indicated by increases in TNF-α, IL-1β, reactive oxygen species, and nitric oxide, which were accompanied by enhanced outward K(+ current and Kv1.3 channel expression. Suppression of microglial Kv1.3 channel activity, either with Kv1.3 channel blockers Margatoxin, 5-(4-Phenoxybutoxypsoralen, or broad-spectrum K(+ channel blocker 4-Aminopyridine, or by knockdown of Kv1.3 expression via transfection of microglia with Kv1.3 siRNA, was found to abrogate the neurotoxic activity of microglia resulting from HIV-1 Tat exposure. Furthermore, HIV-1 Tat-induced neuronal apoptosis was attenuated with the application of supernatant collected from K(+ channel blocker-treated microglia. Lastly, the intracellular signaling pathways associated with Kv1.3 were investigated and enhancement of microglial Kv1.3 was found to correspond with an increase in Erk1/2 mitogen-activated protein kinase activation. These data suggest targeting microglial Kv1.3 channels may be a potential new avenue of therapy for inflammation-mediated neurological disorders.

  20. Acupuncture inhibits microglial activation and inflammatory events in the MPTP-induced mouse model.

    Science.gov (United States)

    Kang, Jun Mo; Park, Hi Joon; Choi, Yeong Gon; Choe, Il Hwan; Park, Jae Hyun; Kim, Yong Sik; Lim, Sabina

    2007-02-01

    Using a mouse model of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease (PD), this study investigated on the neuroprotective effects of acupuncture by examining whether acupuncture contributed to inhibiting microglial activation and inflammatory events. C57BL/6 mice were treated with MPTP (30 mg/kg, i.p.) for 5 consecutive days. Acupuncture was then applied to acupoints Yanglingquan (GB34) and Taichong (LR3) starting 2 h after the first MPTP administration and then at 48 h intervals until the mice were sacrificed for analyses at 1, 3, and 7 days after the last MPTP injection. These experiments demonstrated that acupuncture inhibited the decreased of the tyrosine hydroxylase (TH) immunoreactivity (IR) and generated a neuroprotective effects in the striatum (ST) and the substantia nigra (SN) on days 1, 3, and 7 post-MPTP injections. Acupuncture attenuated the increase of macrophage antigen complex-1 (MAC-1), a marker of microglial activation, at 1 and 3 days and reduced the increases in cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression on days 1, 3, and 7. In MPTP group, striatal dopamine (DA) was measured by 46% at 7 days, whereas DA in the acupuncture group was 78%. On the basis of these results, we suggest that acupuncture could be used as a neuroprotective intervention for the purpose of inhibiting microglial activation and inflammatory events in PD. PMID:17173870

  1. Fingolimod modulates microglial activation to augment markers of remyelination

    Directory of Open Access Journals (Sweden)

    Baker David

    2011-07-01

    Full Text Available Abstract Introduction Microglial activation in multiple sclerosis has been postulated to contribute to long-term neurodegeneration during disease. Fingolimod has been shown to impact on the relapsing remitting phase of disease by modulating autoreactive T-cell egress from lymph organs. In addition, it is brain penetrant and has been shown to exert multiple effects on nervous system cells. Methods In this study, the impact of fingolimod and other sphingosine-1-phosphate receptor active molecules following lysophosphotidyl choline-induced demyelination was examined in the rat telencephalon reaggregate, spheroid cell culture system. The lack of immune system components allowed elucidation of the direct effects of fingolimod on CNS cell types in an organotypic situation. Results Following demyelination, fingolimod significantly augmented expression of myelin basic protein in the remyelination phase. This increase was not associated with changes in neurofilament levels, indicating de novo myelin protein expression not associated with axonal branching. Myelin wrapping was confirmed morphologically using confocal and electron microscopy. Increased remyelination was associated with down-regulation of microglial ferritin, tumor necrosis factor alpha and interleukin 1 during demyelination when fingolimod was present. In addition, nitric oxide metabolites and apoptotic effectors caspase 3 and caspase 7 were reduced during demyelination in the presence of fingolimod. The sphingosine-1-phosphate receptor 1 and 5 agonist BAF312 also increased myelin basic protein levels, whereas the sphingosine-1-phosphate receptor 1 agonist AUY954 failed to replicate this effect on remyelination. Conclusions The results presented indicate that modulation of S1P receptors can ameliorate pathological effectors associated with microglial activation leading to a subsequent increase in protein and morphological markers of remyelination. In addition, sphingosine-1-phosphate

  2. Sinomenine inhibits microglial activation by Aβ and confers neuroprotection

    Directory of Open Access Journals (Sweden)

    Sharma Shiv K

    2011-09-01

    Full Text Available Abstract Background Neuroinflammation is an important contributor to the development of neurodegenerative diseases, including Alzheimer's disease. Thus, there is a keen interest in identifying compounds, especially from herbal sources, that can inhibit neuroinflammation. Amyloid-β (Aβ is a major component of the amyloid plaques present in the brains of Alzheimer's disease patients. Here, we examined whether sinomenine, present in a Chinese medicinal plant, prevents oligomeric Aβ-induced microglial activation and confers protection against neurotoxicity. Methods Oligomeric amyloid-β was prepared from Aβ(1-42. Intracellular reactive oxygen species production was determined using the dye 2',7'-dichlorodihydrofluorescin diacetate. Nitric oxide level was assessed using the Griess reagent. Flow cytometry was used to examine the levels of inflammatory molecules. BV2-conditioned medium was used to treat hippocampal cell line (HT22 and primary hippocampal cells in indirect toxicity experiments. Toxicity was assessed using MTT reduction and TUNEL assays. Results We found that sinomenine prevents the oligomeric Aβ-induced increase in levels of reactive oxygen species and nitric oxide in BV2 microglial cells. In addition, sinomenine reduces levels of Aβ-induced inflammatory molecules. Furthermore, sinomenine protects hippocampal HT22 cells as well as primary hippocampal cells from indirect toxicity mediated by Aβ-treated microglial cells, but has no effect on Aβ-induced direct toxicity to HT22 cells. Finally, we found that conditioned medium from Aβ-treated BV2 cells contains increased levels of nitric oxide and inflammatory molecules, but the levels of these molecules are reduced by sinomenine. Conclusions Sinomenine prevents oligomeric Aβ-induced microglial activation, and confers protection against indirect neurotoxicity to hippocampal cells. These results raise the possibility that sinomenine may have therapeutic potential for the treatment

  3. Microglial recruitment, activation, and proliferation in response to primary demyelination

    DEFF Research Database (Denmark)

    Remington, Leah T; Babcock, Alicia A; Zehntner, Simone P;

    2007-01-01

    microglial numbers. Microglia adopted an activated phenotype during demyelination, up-regulating major histocompatibility class I and B7.2/CD86. A subpopulation of CD45(dim-high) microglia that expressed reduced levels of CD11b emerged during demyelination. These microglia expressed CD11c and were potent...... antigen-presenting cells in vitro. T cells were recruited to the demyelinated corpus callosum but did not appear to be activated. Our study highlights the role of microglia as a heterogeneous population of cells in primary demyelination, with the capacity to present antigen, proliferate, and migrate...

  4. Molecular imaging of microglial activation in amyotrophic lateral sclerosis.

    Directory of Open Access Journals (Sweden)

    Philippe Corcia

    Full Text Available There is growing evidence of activated microglia and inflammatory processes in the cerebral cortex in amyotrophic lateral sclerosis (ALS. Activated microglia is characterized by increased expression of the 18 kDa translocator protein (TSPO in the brain and may be a useful biomarker of inflammation. In this study, we evaluated neuroinflammation in ALS patients using a radioligand of TSPO, (18F-DPA-714. Ten patients with probable or definite ALS (all right-handed, without dementia, and untreated by riluzole or other medication that might bias the binding on the TSPO, were enrolled prospectively and eight healthy controls matched for age underwent a PET study. Comparison of the distribution volume ratios between both groups were performed using a Mann-Whitney's test. Significant increase of distribution of volume ratios values corresponding to microglial activation was found in the ALS sample in primary motor, supplementary motor and temporal cortex (p = 0.009, p = 0.001 and p = 0.004, respectively. These results suggested that the cortical uptake of (18F-DPA-714 was increased in ALS patients during the "time of diagnosis" phase of the disease. This finding might improve our understanding of the pathophysiology of ALS and might be a surrogate marker of efficacy of treatment on microglial activation.

  5. Pyrroloquinoline quinone (PQQ inhibits lipopolysaccharide induced inflammation in part via downregulated NF-κB and p38/JNK activation in microglial and attenuates microglia activation in lipopolysaccharide treatment mice.

    Directory of Open Access Journals (Sweden)

    Chongfei Yang

    Full Text Available Therapeutic strategies designed to inhibit the activation of microglia may lead to significant advancement in the treatment of most neurodegenerative diseases. Pyrroloquinoline quinone (PQQ is a naturally occurring redox cofactor that acts as an essential nutrient, antioxidant, and has been reported to exert potent immunosuppressive effects. In the present study, the anti-inflammatory effects of PQQ was investigated in LPS treated primary microglia cells. Our observations showed that pretreatment with PQQ significantly inhibited the production of NO and PGE2 and suppressed the expression of pro-inflammatory mediators such as iNOS, COX-2, TNF-a, IL-1b, IL-6, MCP-1 and MIP-1a in LPS treated primary microglia cells. The nuclear translocation of NF-κB and the phosphorylation level of p65, p38 and JNK MAP kinase pathways were also inhibited by PQQ in LPS stimulated primary microglia cells. Further a systemic LPS treatment acute inflammation murine brain model was used to study the suppressive effects of PQQ against neuroinflammation in vivo. Mice treated with PQQ demonstrated marked attenuation of neuroinflammation based on Western blotting and immunohistochemistry analysis of Iba1-against antibody in the brain tissue. Indicated that PQQ protected primary cortical neurons against microglia-mediated neurotoxicity. These results collectively suggested that PQQ might be a promising therapeutic agent for alleviating the progress of neurodegenerative diseases associated with microglia activation.

  6. Automatic counting of microglial cell activation and its applications

    Institute of Scientific and Technical Information of China (English)

    Beatriz I Gallego Collado; Pablo de Gracia

    2016-01-01

    Glaucoma is a multifactorial optic neuropathy characterized by the damage and death of the retinal gan-glion cells. This disease results in vision loss and blindness. Any vision loss resulting from the disease cannot be restored and nowadays there is no available cure for glaucoma;however an early detection and treatment, could offer neuronal protection and avoid later serious damages to the visual function. A full understanding of the etiology of the disease will still require the contribution of many scientiifc efforts. Glial activation has been observed in glaucoma, being microglial proliferation a hallmark in this neuro-degenerative disease. A typical project studying these cellular changes involved in glaucoma often needs thousands of images-from several animals-covering different layers and regions of the retina. The gold standard to evaluate them is the manual count. This method requires a large amount of time from special-ized personnel. It is a tedious process and prone to human error. We present here a new method to count microglial cells by using a computer algorithm. It counts in one hour the same number of images that a researcher counts in four weeks, with no loss of reliability.

  7. Hypothermia Reduces Toll-Like Receptor 3-Activated Microglial Interferon-β and Nitric Oxide Production

    Directory of Open Access Journals (Sweden)

    Tomohiro Matsui

    2013-01-01

    Full Text Available Therapeutic hypothermia protects neurons after injury to the central nervous system (CNS. Microglia express toll-like receptors (TLRs that play significant roles in the pathogenesis of sterile CNS injury. To elucidate the possible mechanisms involved in the neuroprotective effect of therapeutic hypothermia, we examined the effects of hypothermic culture on TLR3-activated microglial release of interferon (IFN-β and nitric oxide (NO, which are known to be associated with neuronal cell death. When rat or mouse microglia were cultured under conditions of hypothermia (33°C and normothermia (37°C with a TLR3 agonist, polyinosinic-polycytidylic acid, the production of IFN-β and NO in TLR3-activated microglia at 48 h was decreased by hypothermia compared with that by normothermia. In addition, exposure to recombinant IFN-β and sodium nitroprusside, an NO donor, caused death of rat neuronal pheochromocytoma PC12 cells in a concentration-dependent manner after 24 h. Taken together, these results suggest that the attenuation of microglial production of IFN-β and NO by therapeutic hypothermia leads to the inhibition of neuronal cell death.

  8. CCL2/MCP-1 modulation of microglial activation and proliferation

    Directory of Open Access Journals (Sweden)

    Garcia-Bueno Borja

    2011-07-01

    Full Text Available Abstract Background Monocyte chemoattractant protein (CCL2/MCP-1 is a chemokine that attracts cells involved in the immune/inflammatory response. As microglia are one of the main cell types sustaining inflammation in brain, we proposed here to analyze the direct effects of MCP-1 on cultured primary microglia. Methods Primary microglia and neuronal cultures were obtained from neonatal and embryonic Wistar rats, respectively. Microglia were incubated with different concentrations of recombinant MCP-1 and LPS. Cell proliferation was quantified by measuring incorporation of bromodeoxyuridine (BrdU. Nitrite accumulation was measured using the Griess assay. The expression and synthesis of different proteins was measured by RT-PCR and ELISA. Cell death was quantified by measuring release of LDH into the culture medium. Results MCP-1 treatment (50 ng/ml, 24 h did not induce morphological changes in microglial cultures. Protein and mRNA levels of different cytokines were measured, showing that MCP-1 was not able to induce proinflammatory cytokines (IL-1β, IL6, MIP-1α, either by itself or in combination with LPS. A similar lack of effect was observed when measuring inducible nitric oxide synthase (NOS2 expression or accumulation of nitrites in the culture media as a different indicator of microglial activation. MCP-1 was also unable to alter the expression of different trophic factors that were reduced by LPS treatment. In order to explore the possible release of other products by microglia and their potential neurotoxicity, neurons were co-cultured with microglia: no death of neurons could be detected when treated with MCP-1. However, the presence of MCP-1 induced proliferation of microglia, an effect opposite to that observed with LPS. Conclusion These data indicate that, while causing migration and proliferation of microglia, MCP-1 does not appear to directly activate an inflammatory response in this cell type, and therefore, other factors may be

  9. Microglial activation in the hippocampus of hypercholesterolemic rabbits occurs independent of increased amyloid production

    Directory of Open Access Journals (Sweden)

    Streit Wolfgang J

    2007-08-01

    Full Text Available Abstract Background Rabbits maintained on high-cholesterol diets are known to show increased immunoreactivity for amyloid beta protein in cortex and hippocampus, an effect that is amplified by presence of copper in the drinking water. Hypercholesterolemic rabbits also develop sporadic neuroinflammatory changes. The purpose of this study was to survey microglial activation in rabbits fed cholesterol in the presence or absence of copper or other metal ions, such as zinc and aluminum. Methods Vibratome sections of the rabbit hippocampus and overlying cerebral cortex were examined for microglial activation using histochemistry with isolectin B4 from Griffonia simplicifolia. Animals were scored as showing either focal or diffuse microglial activation with or without presence of rod cells. Results Approximately one quarter of all rabbits fed high-cholesterol diets showed evidence of microglial activation, which was always present in the hippocampus and not in the cortex. Microglial activation was not correlated spatially with increased amyloid immunoreactivity or with neurodegenerative changes and was most pronounced in hypercholesterolemic animals whose drinking water had been supplemented with either copper or zinc. Controls maintained on normal chow were largely devoid of neuroinflammatory changes, but revealed minimal microglial activation in one case. Conclusion Because the increase in intraneuronal amyloid immunoreactivity that results from administration of cholesterol occurs in both cerebral cortex and hippocampus, we deduce that the microglial activation reported here, which is limited to the hippocampus, occurs independent of amyloid accumulation. Furthermore, since neuroinflammation occurred in the absence of detectable neurodegenerative changes, and was also not accompanied by increased astrogliosis, we conclude that microglial activation occurs because of metabolic or biochemical derangements that are influenced by dietary factors.

  10. Vitamin K2 suppresses rotenone-induced microglial activation in vitro

    Science.gov (United States)

    Yu, Yan-xia; Li, Yi-pei; Gao, Feng; Hu, Qing-song; Zhang, Yan; Chen, Dong; Wang, Guang-hui

    2016-01-01

    Aim: Increasing evidence has shown that environmental factors such as rotenone and paraquat induce neuroinflammation, which contributes to the pathogenesis of Parkinson's disease (PD). In this study, we investigated the molecular mechanisms underlying the repression by menaquinone-4 (MK-4), a subtype of vitamin K2, of rotenone-induced microglial activation in vitro. Methods: A microglial cell line (BV2) was exposed to rotenone (1 μmol/L) with or without MK-4 treatment. The levels of TNF-α or IL-1β in 100 μL of cultured media of BV2 cells were measured using ELISA kits. BV2 cells treated with rotenone with or without MK4 were subjected to mitochondrial membrane potential, ROS production, immunofluorescence or immunoblot assays. The neuroblastoma SH-SY5Y cells were treated with conditioned media (CM) of BV2 cells that were exposed to rotenone with or without MK-4 treatment, and the cell viability was assessed using MTT assay. Results: In rotenone-treated BV2 cells, MK-4 (0.5–20 μmol/L) dose-dependently suppressed the upregulation in the expression of iNOS and COX-2 in the cells, as well as the production of TNF-α and IL-1β in the cultured media. MK-4 (5–20 μmol/L) significantly inhibited rotenone-induced nuclear translocation of NF-κB in BV2 cells. MK-4 (5–20 μmol/L) significantly inhibited rotenone-induced p38 activation, ROS production, and caspase-1 activation in BV2 cells. MK-4 (5–20 μmol/L) also restored the mitochondrial membrane potential that had been damaged by rotenone. Exposure to CM from rotenone-treated BV2 cells markedly decreased the viability of SH-SY5Y cells. However, this rotenone-activated microglia-mediated death of SH-SY5Y cells was significantly attenuated when the BV2 cells were co-treated with MK-4 (5–20 μmol/L). Conclusion: Vitamin K2 can directly suppress rotenone-induced activation of microglial BV2 cells in vitro by repressing ROS production and p38 activation. PMID:27498777

  11. Role of orexin A signaling in dietary palmitic acid-activated microglial cells.

    Science.gov (United States)

    Duffy, Cayla M; Yuan, Ce; Wisdorf, Lauren E; Billington, Charles J; Kotz, Catherine M; Nixon, Joshua P; Butterick, Tammy A

    2015-10-01

    Excess dietary saturated fatty acids such as palmitic acid (PA) induce peripheral and hypothalamic inflammation. Hypothalamic inflammation, mediated in part by microglial activation, contributes to metabolic dysregulation. In rodents, high fat diet-induced microglial activation results in nuclear translocation of nuclear factor-kappa B (NFκB), and increased central pro-inflammatory cytokines tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6). The hypothalamic neuropeptide orexin A (OXA, hypocretin 1) is neuroprotective in brain. In cortex, OXA can also reduce inflammation and neurodegeneration through a microglial-mediated pathway. Whether hypothalamic orexin neuroprotection mechanisms depend upon microglia is unknown. To address this issue, we evaluated effects of OXA and PA on inflammatory response in immortalized murine microglial and hypothalamic neuronal cell lines. We demonstrate for the first time in microglial cells that exposure to PA increases gene expression of orexin-1 receptor but not orexin-2 receptor. Pro-inflammatory markers IL-6, TNF-α, and inducible nitric oxide synthase in microglial cells are increased following PA exposure, but are reduced by pretreatment with OXA. The anti-inflammatory marker arginase-1 is increased by OXA. Finally, we show hypothalamic neurons exposed to conditioned media from PA-challenged microglia have increased cell survival only when microglia were pretreated with OXA. These data support the concept that OXA may act as an immunomodulatory regulator of microglia, reducing pro-inflammatory cytokines and increasing anti-inflammatory factors to promote a favorable neuronal microenvironment. PMID:26306651

  12. Allergy Enhances Neurogenesis and Modulates Microglial Activation in the Hippocampus

    Science.gov (United States)

    Klein, Barbara; Mrowetz, Heike; Thalhamer, Josef; Scheiblhofer, Sandra; Weiss, Richard; Aigner, Ludwig

    2016-01-01

    Allergies and their characteristic TH2-polarized inflammatory reactions affect a substantial part of the population. Since there is increasing evidence that the immune system modulates plasticity and function of the central nervous system (CNS), we investigated the effects of allergic lung inflammation on the hippocampus—a region of cellular plasticity in the adult brain. The focus of the present study was on microglia, the resident immune cells of the CNS, and on hippocampal neurogenesis, i.e., the generation of new neurons. C57BL/6 mice were sensitized with a clinically relevant allergen derived from timothy grass pollen (Phl p 5). As expected, allergic sensitization induced high serum levels of allergen-specific immunoglobulins (IgG1 and IgE) and of TH2 cytokines (IL-5 and IL-13). Surprisingly, fewer Iba1+ microglia were found in the granular layer (GL) and subgranular zone (SGZ) of the hippocampal dentate gyrus and also the number of Iba1+MHCII+ cells was lower, indicating a reduced microglial surveillance and activation in the hippocampus of allergic mice. Neurogenesis was analyzed by labeling of proliferating cells with bromodeoxyuridine (BrdU) and determining their fate 4 weeks later, and by quantitative analysis of young immature neurons, i.e., cells expressing doublecortin (DCX). The number of DCX+ cells was clearly increased in the allergy animals. Moreover, there were more BrdU+ cells present in the hippocampus of allergic mice, and these newly born cells had differentiated into neurons as indicated by a higher number of BrdU+NeuN+ cells. In summary, allergy led to a reduced microglia presence and activity and to an elevated level of neurogenesis in the hippocampus. This effect was apparently specific to the hippocampus, as we did not observe these alterations in the subventricular zone (SVZ)/olfactory bulb (OB) system, also a region of high cellular plasticity and adult neurogenesis.

  13. CD45RB is a novel molecular therapeutic target to inhibit Abeta peptide-induced microglial MAPK activation.

    Directory of Open Access Journals (Sweden)

    Yuyan Zhu

    Full Text Available BACKGROUND: Microglial activation, characterized by p38 MAPK or p44/42 MAPK pathway signal transduction, occurs in Alzheimer's disease (AD. Our previous studies demonstrated CD45, a membrane-bound protein tyrosine phosphatase (PTP, opposed beta-amyloid (Abeta peptide-induced microglial activation via inhibition of p44/42 MAPK. Additionally we have shown agonism of the RB isoform of CD45 (CD45RB abrogates lipopolysaccharide (LPS-induced microglial activation. METHODOLOGY AND RESULTS: In this study, CD45RB modulation of Abeta peptide or LPS-activated primary cultured microglial cells was further investigated. Microglial cells were co-treated with "aged" FITC-Abeta(1-42 and multiple CD45 isoform agonist antibodies. Data revealed cross-linking of CD45, particularly the CD45RB isoform, enhances microglial phagocytosis of Abeta(1-42 peptide and inhibits LPS-induced activation of p44/42 and p38 pathways. Co-treatment of microglial cells with agonist CD45 antibodies results in significant inhibition of LPS-induced microglial TNF-alpha and IL-6 release through p44/42 and/or p38 pathways. Moreover, inhibition of either of these pathways augmented CD45RB cross-linking induced microglial phagocytosis of Abeta(1-42 peptide. To investigate the mechanism(s involved, microglial cells were co-treated with a PTP inhibitor (potassium bisperoxo [1,10-phenanthroline oxovanadate; Phen] and Abeta(1-42 peptides. Data showed synergistic induction of microglial activation as evidenced by TNF-alpha and IL-6 release; both of which are demonstrated to be dependent on increased p44/42 and/or p38 activation. Finally, it was observed that cross-linking of CD45RB in the presence of Abeta(1-42 peptide, inhibits co-localization of microglial MHC class II and Abeta peptide; suggesting CD45 activation inhibits the antigen presenting phenotype of microglial cells. CONCLUSION: In summary, p38 MAPK is another novel signaling pathway, besides p44/42, in which CD45RB cross

  14. Tetrandrine suppresses lipopolysaccharide-induced microglial activation by inhibiting NF-κB pathway

    Institute of Scientific and Technical Information of China (English)

    Yang XUE; Ying WANG; De-chun FENG; Bao-guo XIAO; Ling-yun XU

    2008-01-01

    Aim: Microglial activation has been implicated in many neurological diseases. In this study, we examined the effects of tetrandrine (TET), a major pharmacologi-cally-active compound of Chinese herb Stephania tetrandra S Moore on micro-glial activation. Methods: The microglia pretreated with or without TET were activated by lipoopolysaccharide (LPS) in vitro. Nitric oxide (NO) release, superox-ide anion (O2-) generation, as well as TNF-α and intedeukin-6 (IL-6) production by microglia were measured afterwards. Electrophoretic mobility shift assay was performed to determine whether NF-κB activity in microglia was affected by TET treatment. Results: We found that TET inhibited the LPS-induced activation of microglia by decreasing the production of NO and O2-, consequently affecting the release of TNF-α and IL-6 in LPS-induced microglial activation. Such suppressive effect was accompanied by inhibiting transcription factor NF-κB activation. Conclusion: Our results suggest that TET might modulate LPS-induced microglial activation by inhibiting the NF-κB-mediated release of inflammatory factors.

  15. Anti-inflammatory effects and antioxidant activity of dihydroasparagusic acid in lipopolysaccharide-activated microglial cells.

    Science.gov (United States)

    Salemme, Adele; Togna, Anna Rita; Mastrofrancesco, Arianna; Cammisotto, Vittoria; Ottaviani, Monica; Bianco, Armandodoriano; Venditti, Alessandro

    2016-01-01

    The activation of microglia and subsequent release of toxic pro-inflammatory factors are crucially associated with neurodegenerative disease, characterized by increased oxidative stress and neuroinflammation, including Alzheimer and Parkinson diseases and multiple sclerosis. Dihydroasparagusic acid is the reduced form of asparagusic acid, a sulfur-containing flavor component produced by Asparagus plants. It has two thiolic functions able to coordinate the metal ions, and a carboxylic moiety, a polar function, which may enhance excretion of the complexes. Thiol functions are also present in several biomolecules with important physiological antioxidant role as glutathione. The aim of this study is to evaluate the anti-inflammatory and antioxidant potential effect of dihydroasparagusic acid on microglial activation in an in vitro model of neuroinflammation. We have used lipopolysaccharide to induce an inflammatory response in primary rat microglial cultures. Our results suggest that dihydroasparagusic acid significantly prevented lipopolysaccharide-induced production of pro-inflammatory and neurotoxic mediators such as nitric oxide, tumor necrosis factor-α, prostaglandin E2, as well as inducible nitric oxide synthase and cyclooxygenase-2 protein expression and lipoxygenase activity in microglia cells. Moreover it effectively suppressed the level of reactive oxygen species and affected lipopolysaccharide-stimulated activation of mitogen activated protein kinase, including p38, and nuclear factor-kB pathway. These results suggest that dihydroasparagusic acid's neuroprotective properties may be due to its ability to dampen induction of microglial activation. It is a compound that can effectively inhibit inflammatory and oxidative processes that are important factors of the etiopathogenesis of neurodegenerative diseases. PMID:26592472

  16. Astrocyte-Derived CCL2 is Associated with M1 Activation and Recruitment of Cultured Microglial Cells

    Directory of Open Access Journals (Sweden)

    Mingfeng He

    2016-02-01

    Full Text Available Background/Aims: Microglia are an essential player in central nervous system inflammation. Recent studies have demonstrated that the astrocytic chemokine, CCL2, is associated with microglial activation in vivo. However, CCL2-induced microglial activation has not yet been studied in vitro. The purpose of the current study was to understand the role of astrocyte-derived CCL2 in microglial activation and to elucidate the underlying mechanism(s. Methods: Primary astrocytes were pre-treated with CCL2 siRNA and stimulated with TNF-α. The culture medium (CM was collected and added to cultures of microglia, which were incubated with and without CCR2 inhibitor. Microglial cells were analyzed by quantitative RT-PCR to determine whether they polarized to the M1 or M2 state. Microglial migratory ability was assessed by transwell migration assay. Results: TNF-α stimulated the release of CCL2 from astrocytes, even if the culture media containing TNF-α was replaced with fresh media after 3 h. CM from TNF-α-stimulated astrocytes successfully induced microglial activation, which was ascertained by increased activation of M1 and enhanced migration ability. In contrast, CM from astrocytes pretreated with CCL2 siRNA showed no effect on microglial activation, compared to controls. Additionally, microglia pre-treated with RS102895, a CCR2 inhibitor, were resistant to activation by CM from TNF-α-stimulated astrocytes. Conclusion: This study demonstrates that the CCL2/CCR2 pathway of astrocyte-induced microglial activation is associated with M1 polarization and enhanced migration ability, indicating that this pathway could be a useful target to ameliorate inflammation in the central nervous system.

  17. Treatment with polyamine oxidase inhibitor reduces microglial activation and limits vascular injury in ischemic retinopathy.

    Science.gov (United States)

    Patel, C; Xu, Z; Shosha, E; Xing, J; Lucas, R; Caldwell, R W; Caldwell, R B; Narayanan, S P

    2016-09-01

    Retinal vascular injury is a major cause of vision impairment in ischemic retinopathies. Insults such as hyperoxia, oxidative stress and inflammation contribute to this pathology. Previously, we showed that hyperoxia-induced retinal neurodegeneration is associated with increased polyamine oxidation. Here, we are studying the involvement of polyamine oxidases in hyperoxia-induced injury and death of retinal vascular endothelial cells. New-born C57BL6/J mice were exposed to hyperoxia (70% O2) from postnatal day (P) 7 to 12 and were treated with the polyamine oxidase inhibitor MDL 72527 or vehicle starting at P6. Mice were sacrificed after different durations of hyperoxia and their retinas were analyzed to determine the effects on vascular injury, microglial cell activation, and inflammatory cytokine profiling. The results of this analysis showed that MDL 72527 treatment significantly reduced hyperoxia-induced retinal vascular injury and enhanced vascular sprouting as compared with the vehicle controls. These protective effects were correlated with significant decreases in microglial activation as well as levels of inflammatory cytokines and chemokines. In order to model the effects of polyamine oxidation in causing microglial activation in vitro, studies were performed using rat brain microvascular endothelial cells treated with conditioned-medium from rat retinal microglia stimulated with hydrogen peroxide. Conditioned-medium from activated microglial cultures induced cell stress signals and cell death in microvascular endothelial cells. These studies demonstrate the involvement of polyamine oxidases in hyperoxia-induced retinal vascular injury and retinal inflammation in ischemic retinopathy, through mechanisms involving cross-talk between endothelial cells and resident retinal microglia. PMID:27239699

  18. Magnolia polyphenols attenuate oxidative and inflammatory responses in neurons and microglial cells

    OpenAIRE

    Chuang Dennis Y; Chan Ming-Huan; Zong Yijia; Sheng Wenwen; He Yan; Jiang Jing Hua; Simonyi Agnes; Gu Zezong; Fritsche Kevin L; Cui Jiankun; Lee James C; Folk William R; Lubahn Dennis B; Sun Albert Y; Sun Grace Y

    2013-01-01

    Abstract Background The bark of magnolia has been used in Oriental medicine to treat a variety of remedies, including some neurological disorders. Magnolol (Mag) and honokiol (Hon) are isomers of polyphenolic compounds from the bark of Magnolia officinalis, and have been identified as major active components exhibiting anti-oxidative, anti-inflammatory, and neuroprotective effects. In this study, we investigate the ability of these isomers to suppress oxidative stress in neurons stimulated by...

  19. Retinoic acid receptor agonist Am80 inhibits CXCL2 production from microglial BV-2 cells via attenuation of NF-κB signaling.

    Science.gov (United States)

    Takaoka, Yuichiro; Takahashi, Moeka; Kurauchi, Yuki; Hisatsune, Akinori; Seki, Takahiro; Shudo, Koichi; Katsuki, Hiroshi

    2016-09-01

    Accumulating lines of evidence suggest that retinoic acid receptor agonists such as Am80 exerts anti-inflammatory actions in the central nervous system, although detailed mechanisms of the action remain largely unknown. Our previous findings suggest that Am80 provides therapeutic effect on intracerebral hemorrhage in mice via suppression of expression of chemokine (C-X-C motif) ligand 2 (CXCL2). Here we investigated the mechanisms of inhibitory action of Am80 on expression of CXCL2 and other pro-inflammatory factors in microglial BV-2 cells. Pretreatment with Am80 markedly suppressed lipopolysaccharide (LPS)-induced expression of CXCL2 mRNA and release of CXCL2 protein. Am80 had no effect on LPS-induced activation of p38 mitogen-activated protein kinase and extracellular signal-regulated kinase. On the other hand, Am80 prevented LPS-induced nuclear translocation of p65 subunit of NF-κB complex. In addition, total expression levels of p65 and IκBα proteins, as well as of mRNAs encoding p65 and IκBα, were lowered by Am80. Dependence of CXCL2 expression on NF-κB was confirmed by the effect of an NF-κB inhibitor caffeic acid phenethyl ester that abolished LPS-induced CXCL2 expression. Caffeic acid phenethyl ester also abolished LPS-induced expression of inducible nitric oxide synthase, interleukin-1β and tumor necrosis factor α, which may be relevant to the inhibitory effect of Am80 on expression of these pro-inflammatory factors. We additionally found that Am80 attenuated LPS-induced up-regulation of CD14, a co-receptor for Toll-like receptor 4 (TLR4). These results suggest that inhibitory effect on TLR4 signaling mediated by NF-κB pathway underlies the anti-inflammatory action of retinoic acid receptor agonists in microglia. PMID:27351827

  20. Apigenin and luteolin modulate microglial activation via inhibition of STAT1-induced CD40 expression

    Directory of Open Access Journals (Sweden)

    Bickford Paula

    2008-09-01

    Full Text Available Abstract Background It is well known that most neurodegenerative diseases are associated with microglia-mediated inflammation. Our previous research demonstrates that the CD40 signaling is critically involved in microglia-related immune responses in the brain. For example, it is well known that the activation of the signal transducer and activator of transcription (STAT signaling pathway plays a central role in interferon-gamma (IFN-γ-induced microglial CD40 expression. We and others have previously reported that microglial CD40 expression is significantly induced by IFN-γ and amyloid-β (Aβ peptide. Recent studies have shown that certain flavonoids possess anti-inflammatory and neuroprotective properties distinct from their well-known anti-oxidant effects. In particular, flavonoids, apigenin and luteolin have been found to be effective CD40 immunomodulators. Methods Cultured microglia, both N9 and primary derived lines, were treated with flavonoids in the presence of IFN-γ and/or CD40 ligation to assess any anti-inflammatory effects and/or mechanisms. CD40 expression on microglia was analyzed by fluorescence activated cell sorting (FACS. Anti-inflammatory effects and mechanisms were confirmed by ELISA for interlekin-6 (IL-6 and TNF-α, lactate dehydrogenase (LDH assay, and STAT1 Western blotting. Results Apigenin and luteolin concentration-dependently suppressed IFN-γ-induced CD40 expression. Apigenin and luteolin also suppressed microglial TNF-α and IL-6 production stimulated by IFN-gamma challenge in the presence of CD40 ligation. In addition, apigenin and luteolin markedly inhibited IFN-γ-induced phosphorylation of STAT1 with little impact on cell survival. Conclusion Our findings provide further support for apigenin and luteolin's anti-inflammatory effects and suggest that these flavonoids may have neuroprotective/disease-modifying properties in various neurodegenerative disorders, including Alzheimer's disease (AD.

  1. Flipping the switches: CD40 and CD45 modulation of microglial activation states in HIV associated dementia (HAD

    Directory of Open Access Journals (Sweden)

    Jin Jingji

    2011-01-01

    Full Text Available Abstract Microglial dysfunction is associated with the pathogenesis and progression of a number of neurodegenerative disorders including HIV associated dementia (HAD. HIV promotion of an M1 antigen presenting cell (APC - like microglial phenotype, through the promotion of CD40 activity, may impair endogenous mechanisms important for amyloid- beta (Aβ protein clearance. Further, a chronic pro-inflammatory cycle is established in this manner. CD45 is a protein tyrosine phosphatase receptor which negatively regulates CD40L-CD40-induced microglial M1 activation; an effect leading to the promotion of an M2 phenotype better suited to phagocytose and clear Aβ. Moreover, this CD45 mediated activation state appears to dampen harmful cytokine production. As such, this property of microglial CD45 as a regulatory "off switch" for a CD40-promoted M1, APC-type microglia activation phenotype may represent a critical therapeutic target for the prevention and treatment of neurodegeneration, as well as microglial dysfunction, found in patients with HAD.

  2. A common carcinogen benzo[a]pyrene causes neuronal death in mouse via microglial activation.

    Directory of Open Access Journals (Sweden)

    Kallol Dutta

    Full Text Available BACKGROUND: Benzo[a]pyrene (B[a]P belongs to a class of polycyclic aromatic hydrocarbons that serve as micropollutants in the environment. B[a]P has been reported as a probable carcinogen in humans. Exposure to B[a]P can take place by ingestion of contaminated (especially grilled, roasted or smoked food or water, or inhalation of polluted air. There are reports available that also suggests neurotoxicity as a result of B[a]P exposure, but the exact mechanism of action is unknown. METHODOLOGY/PRINCIPAL FINDINGS: Using neuroblastoma cell line and primary cortical neuron culture, we demonstrated that B[a]P has no direct neurotoxic effect. We utilized both in vivo and in vitro systems to demonstrate that B[a]P causes microglial activation. Using microglial cell line and primary microglial culture, we showed for the first time that B[a]P administration results in elevation of reactive oxygen species within the microglia thereby causing depression of antioxidant protein levels; enhanced expression of inducible nitric oxide synthase, that results in increased production of NO from the cells. Synthesis and secretion of proinflammatory cytokines were also elevated within the microglia, possibly via the p38MAP kinase pathway. All these factors contributed to bystander death of neurons, in vitro. When administered to animals, B[a]P was found to cause microglial activation and astrogliosis in the brain with subsequent increase in proinflammatory cytokine levels. CONCLUSIONS/SIGNIFICANCE: Contrary to earlier published reports we found that B[a]P has no direct neurotoxic activity. However, it kills neurons in a bystander mechanism by activating the immune cells of the brain viz the microglia. For the first time, we have provided conclusive evidence regarding the mechanism by which the micropollutant B[a]P may actually cause damage to the central nervous system. In today's perspective, where rising pollution levels globally are a matter of grave concern, our

  3. Microglial activation and neuroinflammation in Alzheimer's disease: a critical examination of recent history

    Directory of Open Access Journals (Sweden)

    Wolfgang J Streit

    2010-06-01

    Full Text Available The neurofibrillary degeneration that occurs in Alzheimer’s disease (AD is thought to be the result of a chronic and damaging neuroinflammatory response mediated by neurotoxic substances produced by activated microglial cells. This neuroinflammation hypothesis of AD pathogenesis has led to numerous clinical trials with anti-inflammatory drugs, none of which have shown clear benefits for slowing or preventing disease onset and progression. In this paper, I make the point that AD is not an inflammatory condition, and reconstruct the sequence of events during the 1980s and 1990s that I believe led to the development of this faulty theory.

  4. Microglial activation of p38 contributes to scorpion envenomation-induced hyperalgesia.

    Science.gov (United States)

    Niu, Qing-Shan; Jiang, Feng; Hua, Li-Ming; Fu, Jin; Jiao, Yun-Lu; Ji, Yong-Hua; Ding, Gang

    2013-10-25

    Intraplantar (i.pl.) injection of BmK I, a receptor site 3-specific modulator of voltage-gated sodium channels (VGSCs) from the venom of scorpion Buthus martensi Karsch (BmK), was shown to induce long-lasting and spontaneous nociceptive responses as demonstrated through experiments utilizing primary thermal and mirror-imaged mechanical hypersensitivity with different time course of development in rats. In this study, microglia was activated on both sides of L4-L5 spinal cord by i.pl. injection of BmK I. Meanwhile, the activation of p38/MAPK in L4-L5 spinal cord was found to be co-expressed with OX-42, the cell marker of microglia. The unilateral thermal and bilateral mechanical pain hypersensitivity of rat induced by BmK I was suppressed in a dose-dependent manner following pretreatment with SB203580 (a specific inhibitor of p-p38). Interestingly, microglia activity was also reduced in the presence of SB203580, which suggests that BmK I-induced microglial activation is mediated by p38/MAPK pathway. Combined with previously published literature, the results of this study demonstrate that p38-dependent microglial activation plays a role in scorpion envenomation-induced pain-related behaviors. PMID:24064352

  5. Expression of Tau40 induces activation of cultured rat microglial cells.

    Directory of Open Access Journals (Sweden)

    Lu Wang

    Full Text Available Accumulation of microtubule-associated protein tau has been observed in the brain of aging and tauopathies. Tau was observed in microglia, but its role is not illustrated. By immunofluorescence staining and the fractal dimension value assay in the present study, we observed that microglia were activated in the brains of rats and mice during aging, simultaneously, the immunoreactivities of total tau and the phosphorylated tau were significantly enhanced in the activated microglia. Furtherly by transient transfection of tau40 (human 2N/4R tau into the cultured rat microglia, we demonstrated that expression of tau40 increased the level of Iba1, indicating activation of microglia. Moreover, expression of tau40 significantly enhanced the membranous localization of the phosphorylated tau at Ser396 in microglia possibly by a mechanism involving protein phosphatase 2A, extracellular signal-regulated kinase and glycogen synthase kinase-3β. It was also found that expression of tau40 promoted microglial migration and phagocytosis, but not proliferation. And we observed increased secretion of several cytokines, including interleukin (IL-1β, IL-6, IL-10, tumor necrosis factor-α and nitric oxide after the expression of tau40. These data suggest a novel role of human 2N/4R tau in microglial activation.

  6. Maternal immune activation evoked by polyinosinic:polycytidylic acid does not evoke microglial cell activation in the embryo.

    Directory of Open Access Journals (Sweden)

    Silke eSmolders

    2015-08-01

    Full Text Available Several studies have indicated that inflammation during pregnancy increases the risk for the development of neuropsychiatric disorders in the offspring. Morphological brain abnormalities combined with deviations in the inflammatory status of the brain can be observed in patients of both autism and schizophrenia. It was shown that acute infection can induce changes in maternal cytokine levels which in turn are suggested to affect fetal brain development and increase the risk on the development of neuropsychiatric disorders in the offspring. Animal models of maternal immune activation reproduce the etiology of neurodevelopmental disorders such as schizophrenia and autism. In this study the poly (I:C model was used to mimic viral immune activation in pregnant mice in order to assess the activation status of fetal microglia in these developmental disorders. Because microglia are the resident immune cells of the brain they were expected to be activated due to the inflammatory stimulus.Microglial cell density and activation level in the fetal cortex and hippocampus were determined. Despite the presence of a systemic inflammation in the pregnant mice, there was no significant difference in fetal microglial cell density or immunohistochemically determined activation level between the control and inflammation group. These data indicate that activation of the fetal microglial cells is not likely to be responsible for the inflammation induced deficits in the offspring in this model.

  7. Botanical Polyphenols Mitigate Microglial Activation and Microglia-Induced Neurotoxicity: Role of Cytosolic Phospholipase A2.

    Science.gov (United States)

    Chuang, Dennis Y; Simonyi, Agnes; Cui, Jiankun; Lubahn, Dennis B; Gu, Zezong; Sun, Grace Y

    2016-09-01

    Microglia play a significant role in the generation and propagation of oxidative/nitrosative stress, and are the basis of neuroinflammatory responses in the central nervous system. Upon stimulation by endotoxins such as lipopolysaccharides (LPS), these cells release pro-inflammatory factors which can exert harmful effects on surrounding neurons, leading to secondary neuronal damage and cell death. Our previous studies demonstrated the effects of botanical polyphenols to mitigate inflammatory responses induced by LPS, and highlighted an important role for cytosolic phospholipase A2 (cPLA2) upstream of the pro-inflammatory pathways (Chuang et al. in J Neuroinflammation 12(1):199, 2015. doi: 10.1186/s12974-015-0419-0 ). In this study, we investigate the action of botanical compounds and assess whether suppression of cPLA2 in microglia is involved in the neurotoxic effects on neurons. Differentiated SH-SY5Y neuroblastoma cells were used to test the neurotoxicity of conditioned medium from stimulated microglial cells, and WST-1 assay was used to assess for the cell viability of SH-SY5Y cells. Botanicals such as quercetin and honokiol (but not cyanidin-3-O-glucoside, 3CG) were effective in inhibiting LPS-induced nitric oxide (NO) production and phosphorylation of cPLA2. Conditioned medium from BV-2 cells stimulated with LPS or IFNγ caused neurotoxicity to SH-SY5Y cells. Decrease in cell viability could be ameliorated by pharmacological inhibitors for cPLA2 as well as by down-regulating cPLA2 with siRNA. Botanicals effective in inhibition of LPS-induced NO and cPLA2 phosphorylation were also effective in ameliorating microglial-induced neurotoxicity. Results demonstrated cytotoxic factors from activated microglial cells to cause damaging effects to neurons and potential use of botanical polyphenols to ameliorate the neurotoxic effects. PMID:27339657

  8. Poly(ADP-ribosepolymerase-1 modulates microglial responses to amyloid β

    Directory of Open Access Journals (Sweden)

    Kauppinen Tiina M

    2011-11-01

    Full Text Available Abstract Background Amyloid β (Aβ accumulates in Alzheimer's disease (AD brain. Microglial activation also occurs in AD, and this inflammatory response may contribute to disease progression. Microglial activation can be induced by Aβ, but the mechanisms by which this occurs have not been defined. The nuclear enzyme poly(ADP-ribose polymerase-1 (PARP-1 regulates microglial activation in response to several stimuli through its interactions with the transcription factor, NF-κB. The purpose of this study was to evaluate whether PARP-1 activation is involved in Aβ-induced microglial activation, and whether PARP-1 inhibition can modify microglial responses to Aβ. Methods hAPPJ20 mice, which accumulate Aβ with ageing, were crossed with PARP-1-/- mice to assess the effects of PARP-1 depletion on microglial activation, hippocampal synaptic integrity, and cognitive function. Aβ peptide was also injected into brain of wt and PARP-1-/- mice to directly determine the effects of PARP-1 on Aβ-induced microglial activation. The effect of PARP-1 on Aβ-induced microglial cytokine production and neurotoxicity was evaluated in primary microglia cultures and in microglia-neuron co-cultures, utilizing PARP-1-/- cells and a PARP-1 inhibitor. NF-κB activation was evaluated in microglia infected with a lentivirus reporter gene. Results The hAPPJ20 mice developed microglial activation, reduced hippocampal CA1 calbindin expression, and impaired novel object recognition by age 6 months. All of these features were attenuated in hAPPJ20/PARP-1-/- mice. Similarly, Aβ1-42 injected into mouse brain produced a robust microglial response in wild-type mice, and this was blocked in mice lacking PARP-1 expression or activity. Studies using microglial cultures showed that PARP-1 activity was required for Aβ-induced NF-κB activation, morphological transformation, NO release, TNFα release, and neurotoxicity. Conversely, PARP-1 inhibition increased release of the

  9. Ginsenoside Rb1 attenuates activated microglia-induced neuronal damage

    Institute of Scientific and Technical Information of China (English)

    Lining Ke; Wei Guo; Jianwen Xu; Guodong Zhang; Wei Wang; Wenhua Huang

    2014-01-01

    The microglia-mediated inlfammatory reaction promotes neuronal damage under cerebral isch-emia/hypoxia conditions. We therefore speculated that inhibition of hypoxia-induced microglial activation may alleviate neuronal damage. To test this hypothesis, we co-cultured ginsenoside Rb1, an active component of ginseng, and cortical neurons. Ginsenoside Rb1 protected neuronal morphology and structure in a single hypoxic culture system and in a hypoxic co-culture system with microglia, and reduced neuronal apoptosis and caspase-3 production. The protective effect was observable prior to placing in co-culture. Additionally, ginsenoside Rb1 inhibited levels of tumor necrosis factor-αin a co-culture system containing activated N9 microglial cells. Ginse-noside Rb1 also signiifcantly decreased nitric oxide and superoxide production induced by N9 microglia. Our ifndings indicate that ginsenoside Rb1 attenuates damage to cerebral cortex neu-rons by downregulation of nitric oxide, superoxide, and tumor necrosis factor-αexpression in hypoxia-activated microglia.

  10. Subneurotoxic copper(II)-induced NF-κB-dependent microglial activation is associated with mitochondrial ROS

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Zhuqin; Yu, Fengxiang; Gong, Ping; Qiu, Yu; Zhou, Wei; Cui, Yongyao; Li, Juan, E-mail: lijuanpharm@gmail.com; Chen, Hongzhuan, E-mail: yaoli@shsmu.edu.cn

    2014-04-15

    Microglia-mediated neuroinflammation and the associated neuronal damage play critical roles in the pathogenesis of neurodegenerative disorders. Evidence shows an elevated concentration of extracellular copper(II) in the brains of these disorders, which may contribute to neuronal death through direct neurotoxicity. Here we explored whether extracellular copper(II) triggers microglial activation. Primary rat microglia and murine microglial cell line BV-2 cells were cultured and treated with copper(II). The content of tumor necrosis factor-α (TNF-α) and nitric oxide in the medium was determined. Extracellular hydrogen peroxide was quantified by a fluorometric assay with Amplex Red. Mitochondrial superoxide was measured by MitoSOX oxidation. At subneurotoxic concentrations, copper(II) treatment induced a dose- and time-dependent release of TNF-α and nitric oxide from microglial cells, and caused an indirect, microglia-mediated neurotoxicity that was blocked by inhibition of TNF-α and nitric oxide production. Copper(II)-initiated microglial activation was accompanied with reduced IkB-α expression as well as phosphorylation and translocation of nuclear factor-κB (NF-κB) p65 and was blocked by NF-κB inhibitors (BAY11-7082 and SC-514). Moreover, copper(II) treatment evoked a rapid release of hydrogen peroxide from microglial cells, an effect that was not affected by NADPH oxidase inhibitors. N-acetyl-cysteine, a scavenger of reactive oxygen species (ROS), abrogated copper(II)-elicited microglial release of TNF-α and nitric oxide and subsequent neurotoxicity. Importantly, mitochondrial production of superoxide, paralleled to extracellular release of hydrogen peroxide, was induced after copper(II) stimulation. Our findings suggest that extracellular copper(II) at subneurotoxic concentrations could trigger NF-κB-dependent microglial activation and subsequent neurotoxicity. NADPH oxidase-independent, mitochondria-derived ROS may be involved in this activation

  11. Subneurotoxic copper(II)-induced NF-κB-dependent microglial activation is associated with mitochondrial ROS

    International Nuclear Information System (INIS)

    Microglia-mediated neuroinflammation and the associated neuronal damage play critical roles in the pathogenesis of neurodegenerative disorders. Evidence shows an elevated concentration of extracellular copper(II) in the brains of these disorders, which may contribute to neuronal death through direct neurotoxicity. Here we explored whether extracellular copper(II) triggers microglial activation. Primary rat microglia and murine microglial cell line BV-2 cells were cultured and treated with copper(II). The content of tumor necrosis factor-α (TNF-α) and nitric oxide in the medium was determined. Extracellular hydrogen peroxide was quantified by a fluorometric assay with Amplex Red. Mitochondrial superoxide was measured by MitoSOX oxidation. At subneurotoxic concentrations, copper(II) treatment induced a dose- and time-dependent release of TNF-α and nitric oxide from microglial cells, and caused an indirect, microglia-mediated neurotoxicity that was blocked by inhibition of TNF-α and nitric oxide production. Copper(II)-initiated microglial activation was accompanied with reduced IkB-α expression as well as phosphorylation and translocation of nuclear factor-κB (NF-κB) p65 and was blocked by NF-κB inhibitors (BAY11-7082 and SC-514). Moreover, copper(II) treatment evoked a rapid release of hydrogen peroxide from microglial cells, an effect that was not affected by NADPH oxidase inhibitors. N-acetyl-cysteine, a scavenger of reactive oxygen species (ROS), abrogated copper(II)-elicited microglial release of TNF-α and nitric oxide and subsequent neurotoxicity. Importantly, mitochondrial production of superoxide, paralleled to extracellular release of hydrogen peroxide, was induced after copper(II) stimulation. Our findings suggest that extracellular copper(II) at subneurotoxic concentrations could trigger NF-κB-dependent microglial activation and subsequent neurotoxicity. NADPH oxidase-independent, mitochondria-derived ROS may be involved in this activation

  12. Essential roles of mitochondrial depolarization in neuron loss through microglial activation and attraction toward neurons.

    Science.gov (United States)

    Nam, Min-Kyung; Shin, Hyun-Ah; Han, Ji-Hye; Park, Dae-Wook; Rhim, Hyangshuk

    2013-04-10

    As life spans increased, neurodegenerative disorders that affect aging populations have also increased. Progressive neuronal loss in specific brain regions is the most common cause of neurodegenerative disease; however, key determinants mediating neuron loss are not fully understood. Using a model of mitochondrial membrane potential (ΔΨm) loss, we found only 25% cell loss in SH-SY5Y (SH) neuronal mono-cultures, but interestingly, 85% neuronal loss occurred when neurons were co-cultured with BV2 microglia. SH neurons overexpressing uncoupling protein 2 exhibited an increase in neuron-microglia interactions, which represent an early step in microglial phagocytosis of neurons. This result indicates that ΔΨm loss in SH neurons is an important contributor to recruitment of BV2 microglia. Notably, we show that ΔΨm loss in BV2 microglia plays a crucial role in microglial activation and phagocytosis of damaged SH neurons. Thus, our study demonstrates that ΔΨm loss in both neurons and microglia is a critical determinant of neuron loss. These findings also offer new insights into neuroimmunological and bioenergetical aspects of neurodegenerative disease.

  13. Atorvastatin prevents age-related and amyloid-β-induced microglial activation by blocking interferon-γ release from natural killer cells in the brain

    Directory of Open Access Journals (Sweden)

    Clarke Rachael

    2011-03-01

    Full Text Available Abstract Background Microglial function is modulated by several factors reflecting the numerous receptors expressed on the cell surface, however endogenous factors which contribute to the age-related increase in microglial activation remain largely unknown. One possible factor which may contribute is interferon-γ (IFNγ. IFNγ has been shown to increase in the aged brain and potently activates microglia, although its endogenous cell source in the brain remains unidentified. Methods Male Wistar rats were used to assess the effect of age and amyloid-β (Aβ on NK cell infiltration into the brain. The effect of the anti-inflammatory compound, atorvastatin was also assessed under these conditions. We measured cytokine and chemokine (IFNγ, IL-2, monocyte chemoattractant protein-1 (MCP-1 and IFNγ-induced protein 10 kDa (IP-10, expression in the brain by appropriate methods. We also looked at NK cell markers, CD161, NKp30 and NKp46 using flow cytometry and western blot. Results Natural killer (NK cells are a major source of IFNγ in the periphery and here we report the presence of CD161+ NKp30+ cells and expression of CD161 and NKp46 in the brain of aged and Aβ-treated rats. Furthermore, we demonstrate that isolated CD161+ cells respond to interleukin-2 (IL-2 by releasing IFNγ. Atorvastatin, the HMG-CoA reductase inhibitor, attenuates the increase in CD161 and NKp46 observed in hippocampus of aged and Aβ-treated rats. This was paralleled by a decrease in IFNγ, markers of microglial activation and the chemokines, MCP-1 and IP-10 which are chemotactic for NK cells. Conclusions We propose that NK cells contribute to the age-related and Aβ-induced neuroinflammatory changes and demonstrate that these changes can be modulated by atorvastatin treatment.

  14. Atorvastatin prevents age-related and amyloid-beta-induced microglial activation by blocking interferon-gamma release from natural killer cells in the brain

    LENUS (Irish Health Repository)

    Lyons, Anthony

    2011-03-31

    Abstract Background Microglial function is modulated by several factors reflecting the numerous receptors expressed on the cell surface, however endogenous factors which contribute to the age-related increase in microglial activation remain largely unknown. One possible factor which may contribute is interferon-γ (IFNγ). IFNγ has been shown to increase in the aged brain and potently activates microglia, although its endogenous cell source in the brain remains unidentified. Methods Male Wistar rats were used to assess the effect of age and amyloid-β (Aβ) on NK cell infiltration into the brain. The effect of the anti-inflammatory compound, atorvastatin was also assessed under these conditions. We measured cytokine and chemokine (IFNγ, IL-2, monocyte chemoattractant protein-1 (MCP-1) and IFNγ-induced protein 10 kDa (IP-10)), expression in the brain by appropriate methods. We also looked at NK cell markers, CD161, NKp30 and NKp46 using flow cytometry and western blot. Results Natural killer (NK) cells are a major source of IFNγ in the periphery and here we report the presence of CD161+ NKp30+ cells and expression of CD161 and NKp46 in the brain of aged and Aβ-treated rats. Furthermore, we demonstrate that isolated CD161+ cells respond to interleukin-2 (IL-2) by releasing IFNγ. Atorvastatin, the HMG-CoA reductase inhibitor, attenuates the increase in CD161 and NKp46 observed in hippocampus of aged and Aβ-treated rats. This was paralleled by a decrease in IFNγ, markers of microglial activation and the chemokines, MCP-1 and IP-10 which are chemotactic for NK cells. Conclusions We propose that NK cells contribute to the age-related and Aβ-induced neuroinflammatory changes and demonstrate that these changes can be modulated by atorvastatin treatment.

  15. Exposure to electromagnetic field attenuates oxygen-glucose deprivation-induced microglial cell death by reducing intracellular Ca(2+) and ROS.

    Science.gov (United States)

    Duong, Cao Nguyen; Kim, Jae Young

    2016-01-01

    Purpose The aim of this research was to demonstrate the protective effects of electromagnetic field (EMF) exposure on the human microglial cell line, HMO6, against ischemic cell death induced by in vitro oxygen-glucose deprivation (OGD). Materials and methods HMO6 cells were cultured for 4 h under OGD with or without exposure to EMF with different combinations of frequencies and intensities (10, 50, or 100 Hz/1 mT and 50 Hz/0.01, 0.1, or 1 mT). Cell survival, intracellular calcium and reactive oxygen species (ROS) levels were measured. Results OGD caused significant HMO6 cell death as well as elevation of intracellular Ca(2+) and ROS levels. Among different combinations of EMF frequencies and intensities, 50 Hz/1 mT EMF was the most potent to attenuate OGD-induced cell death and intracellular Ca(2+) and ROS levels. A significant but less potent protective effect was also found at 10 Hz/1 mT, whereas no protective effect was found at other combinations of EMF. A xanthine oxidase inhibitor reversed OGD-induced ROS production and cell death, while NADPH oxidase and mitochondrial respiration chain complex II inhibitors did not affect cell death. Conclusions 50 Hz/1 mT EMF protects human microglial cells from OGD-induced cell death by interfering with OGD-induced elevation of intracellular Ca(2+) and ROS levels, and xanthine oxidase is one of the main mediators involved in OGD-induced HMO6 cell death. Non-invasive treatment of EMF radiation may be clinically useful to attenuate hypoxic-ischemic brain injury. PMID:26882219

  16. Cocaine-mediated microglial activation involves the ER stress-autophagy axis.

    Science.gov (United States)

    Guo, Ming-Lei; Liao, Ke; Periyasamy, Palsamy; Yang, Lu; Cai, Yu; Callen, Shannon E; Buch, Shilpa

    2015-01-01

    Cocaine abuse leads to neuroinflammation, which, in turn, contributes to the pathogenesis of neurodegeneration associated with advanced HIV-1 infection. Autophagy plays important roles in both innate and adaptive immune responses. However, the possible functional link between cocaine and autophagy has not been explored before. Herein, we demonstrate that cocaine exposure induced autophagy in both BV-2 and primary rat microglial cells as demonstrated by a dose- and time-dependent induction of autophagy-signature proteins such as BECN1/Beclin 1, ATG5, and MAP1LC3B. These findings were validated wherein cocaine treatment of BV-2 cells resulted in increased formation of puncta in cells expressing either endogenous MAP1LC3B or overexpressing GFP-MAP1LC3B. Specificity of cocaine-induced autophagy was confirmed by treating cells with inhibitors of autophagy (3-MA and wortmannin). Intriguingly, cocaine-mediated induction of autophagy involved upstream activation of 2 ER stress pathways (EIF2AK3- and ERN1-dependent), as evidenced by the ability of the ER stress inhibitor salubrinal to ameliorate cocaine-induced autophagy. In vivo validation of these findings demonstrated increased expression of BECN1, ATG5, and MAP1LC3B-II proteins in cocaine-treated mouse brains compared to untreated animals. Increased autophagy contributes to cocaine-mediated activation of microglia since pretreatment of cells with wortmannin resulted in decreased expression and release of inflammatory factors (TNF, IL1B, IL6, and CCL2) in microglial cells. Taken together, our findings suggest that cocaine exposure results in induction of autophagy that is closely linked with neuroinflammation. Targeting autophagic proteins could thus be considered as a therapeutic strategy for the treatment of cocaine-related neuroinflammation diseases.

  17. Cocaine-mediated microglial activation involves the ER stress-autophagy axis.

    Science.gov (United States)

    Guo, Ming-Lei; Liao, Ke; Periyasamy, Palsamy; Yang, Lu; Cai, Yu; Callen, Shannon E; Buch, Shilpa

    2015-01-01

    Cocaine abuse leads to neuroinflammation, which, in turn, contributes to the pathogenesis of neurodegeneration associated with advanced HIV-1 infection. Autophagy plays important roles in both innate and adaptive immune responses. However, the possible functional link between cocaine and autophagy has not been explored before. Herein, we demonstrate that cocaine exposure induced autophagy in both BV-2 and primary rat microglial cells as demonstrated by a dose- and time-dependent induction of autophagy-signature proteins such as BECN1/Beclin 1, ATG5, and MAP1LC3B. These findings were validated wherein cocaine treatment of BV-2 cells resulted in increased formation of puncta in cells expressing either endogenous MAP1LC3B or overexpressing GFP-MAP1LC3B. Specificity of cocaine-induced autophagy was confirmed by treating cells with inhibitors of autophagy (3-MA and wortmannin). Intriguingly, cocaine-mediated induction of autophagy involved upstream activation of 2 ER stress pathways (EIF2AK3- and ERN1-dependent), as evidenced by the ability of the ER stress inhibitor salubrinal to ameliorate cocaine-induced autophagy. In vivo validation of these findings demonstrated increased expression of BECN1, ATG5, and MAP1LC3B-II proteins in cocaine-treated mouse brains compared to untreated animals. Increased autophagy contributes to cocaine-mediated activation of microglia since pretreatment of cells with wortmannin resulted in decreased expression and release of inflammatory factors (TNF, IL1B, IL6, and CCL2) in microglial cells. Taken together, our findings suggest that cocaine exposure results in induction of autophagy that is closely linked with neuroinflammation. Targeting autophagic proteins could thus be considered as a therapeutic strategy for the treatment of cocaine-related neuroinflammation diseases. PMID:26043790

  18. Anti-inflammatory Activity of 1-docosanoyl Cafferate Isolated from Rhus verniciflua in LPS-stimulated BV2 Microglial Cells

    OpenAIRE

    Lee, Jae-Won; Cheong, Il-Young; Kim, Hae-Sung; Lee, Jae Jun; Lee, Yong-Suk; Kwon, Yong-Soo; Kim, Myong-Jo; Lee, Hee Jae; Kim, Sung-Soo; Chun, Wanjoo

    2011-01-01

    Although various derivatives of caffeic acid have been reported to possess a wide variety of biological activities such as protection of neuronal cells against excitotoxicity, the biological activity of 1-docosanoyl cafferate (DC) has not been examined. The objective of the present study was to evaluate the anti-inflammatory effects of DC, isolated from the stem bark of Rhus verniciflua, on lipopolysaccharide (LPS)-stimulated BV2 microglial cells. Pretreatment of cells with DC significantly a...

  19. Bone marrow-derived mesenchymal stem cells maintain the resting phenotype of microglia and inhibit microglial activation.

    Directory of Open Access Journals (Sweden)

    Ke Yan

    Full Text Available Many studies have shown that microglia in the activated state may be neurotoxic. It has been proven that uncontrolled or over-activated microglia play an important role in many neurodegenerative disorders. Bone marrow-derived mesenchymal stem cells (BMSCs have been shown in many animal models to have a therapeutic effect on neural damage. Such a therapeutic effect is attributed to the fact that BMSCs have the ability to differentiate into neurons and to produce trophic factors, but there is little information available in the literature concerning whether BMSCs play a therapeutic role by affecting microglial activity. In this study, we triggered an inflammatory response situation in vitro by stimulating microglia with the bacterial endotoxin lipopolysaccharide (LPS, and then culturing these microglia with BMSC-conditioned medium (BMSC-CM. We found that BMSC-CM significantly inhibited proliferation and secretion of pro-inflammatory factors by activated microglia. Furthermore, we found that the phagocytic capacity of microglia was also inhibited by BMSC-CM. Finally, we investigated whether the induction of apoptosis and the production of nitric oxide (NO were involved in the inhibition of microglial activation. We found that BMSC-CM significantly induced apoptosis of microglia, while no apoptosis was apparent in the LPS-stimulated microglia. Our study also provides evidence that NO participates in the inhibitory effect of BMSCs. Our experimental results provide evidence that BMSCs have the ability to maintain the resting phenotype of microglia or to control microglial activation through their production of several factors, indicating that BMSCs could be a promising therapeutic tool for treatment of diseases associated with microglial activation.

  20. Ganoderma lucidum Protects Dopaminergic Neuron Degeneration through Inhibition of Microglial Activation

    Directory of Open Access Journals (Sweden)

    Ruiping Zhang

    2011-01-01

    Full Text Available Abundant evidence has suggested that neuroinflammation participates in the pathogenesis of Parkinson's disease (PD. The emerging evidence has supported that microglia may play key roles in the progressive neurodegeneration in PD and might be a promising therapeutic target. Ganoderma lucidum (GL, a traditional Chinese medicinal herb, has been shown potential neuroprotective effects in our clinical trials that make us to speculate that it might possess potent anti-inflammatory and immunomodulating properties. To test this hypothesis, we investigated the potential neuroprotective effect of GL and possible underlying mechanism of action through protecting microglial activation using co-cultures of dopaminergic neurons and microglia. The microglia is activated by LPS and MPP+-treated MES 23.5 cell membranes. Meanwhile, GL extracts significantly prevent the production of microglia-derived proinflammatory and cytotoxic factors [nitric oxide, tumor necrosis factor-α (TNF-α, interlukin 1β (IL-1β] in a dose-dependent manner and down-regulate the TNF-α and IL-1β expressions on mRNA level as well. In conclusion, our results support that GL may be a promising agent for the treatment of PD through anti-inflammation.

  1. Anti-Inflammatory Activity of Bee Venom in BV2 Microglial Cells: Mediation of MyD88-Dependent NF-κB Signaling Pathway.

    Science.gov (United States)

    Im, Eun Ju; Kim, Su Jung; Hong, Seung Bok; Park, Jin-Kyu; Rhee, Man Hee

    2016-01-01

    Bee venom has long been used as a traditional folk medicine in Korea. It has been reportedly used for the treatment of arthritis, cancer, and inflammation. Although its anti-inflammatory activity in lipopolysaccharide- (LPS-) stimulated inflammatory cells has been reported, the exact mechanism of its anti-inflammatory action has not been fully elucidated. Therefore, the aim of this study was to investigate the anti-inflammatory mechanism of bee venom in BV2 microglial cells. We first investigated whether NO production in LPS-activated BV2 cells was inhibited by bee venom, and further iNOS mRNA and protein expressions were determined. The mRNA and protein levels of proinflammatory cytokines were examined using semiquantitative RT-PCR and immunoblotting, respectively. Moreover, modulation of the transcription factor NF-κB by bee venom was also investigated using a luciferase assay. LPS-induced NO production in BV2 microglial cells was significantly inhibited in a concentration-dependent manner upon pretreatment with bee venom. Bee venom markedly reduced the mRNA expression of COX-2, TNF-α, IL-1β, and IL-6 and suppressed LPS-induced activation of MyD88 and IRAK1 and phosphorylation of TAK1. Moreover, NF-κB translocation by IKKα/β phosphorylation and subsequent IκB-α degradation were also attenuated. Thus, collectively, these results indicate that bee venom exerts its anti-inflammatory activity via the IRAK1/TAK1/NF-κB signaling pathway. PMID:27563334

  2. Quercetin Attenuates Inflammatory Responses in BV-2 Microglial Cells: Role of MAPKs on the Nrf2 Pathway and Induction of Heme Oxygenase-1.

    Directory of Open Access Journals (Sweden)

    Grace Y Sun

    Full Text Available A large group of flavonoids found in fruits and vegetables have been suggested to elicit health benefits due mainly to their anti-oxidative and anti-inflammatory properties. Recent studies with immune cells have demonstrated inhibition of these inflammatory responses through down-regulation of the pro-inflammatory pathway involving NF-κB and up-regulation of the anti-oxidative pathway involving Nrf2. In the present study, the murine BV-2 microglial cells were used to compare anti-inflammatory activity of quercetin and cyanidin, two flavonoids differing by their alpha, beta keto carbonyl group. Quercetin was 10 folds more potent than cyanidin in inhibition of lipopolysaccharide (LPS-induced NO production as well as stimulation of Nrf2-induced heme-oxygenase-1 (HO-1 protein expression. In addition, quercetin demonstrated enhanced ability to stimulate HO-1 protein expression when cells were treated with LPS. In an attempt to unveil mechanism(s for quercetin to enhance Nrf2/HO-1 activity under endotoxic stress, results pointed to an increase in phospho-p38MAPK expression upon addition of quercetin to LPS. In addition, pharmacological inhibitors for phospho-p38MAPK and MEK1/2 for ERK1/2 further showed that these MAPKs target different sites of the Nrf2 pathway that regulates HO-1 expression. However, inhibition of LPS-induced NO by quercetin was not fully reversed by TinPPIX, a specific inhibitor for HO-1 activity. Taken together, results suggest an important role of quercetin to regulate inflammatory responses in microglial cells and its ability to upregulate HO-1 against endotoxic stress through involvement of MAPKs.

  3. Lipopolysaccharide-activated microglial-induced neuroglial cell differentiation in bone marrow mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    Xiaoguang Luo; Chunlin Ge; Yan Ren; Hongmei Yu; Zhe Wu; Qiushuang Wang; Chaodong Zhang

    2008-01-01

    BACKGROUND: Microglia are very sensitive to environmental changes, often becoming activated by pathological conditions. Activated microglia can exert a dual role in injury and repair in various diseases of the central nervous system, including cerebral ischemia, Parkinson's disease, and Alzheimer's disease. OBJECTIVE: An immortal microglial cell line, BV2, was treated with varying concentrations of lipopolysaccharide (LPS) to induce a pathological situation. Supernatant was harvested and incubated with bone marrow mesenchymal stem cells and, concomitantly, bone marrow mesenchymal stem cell differentiation was observed. DESIGN: A controlled observation, in vitro experiment. SETTING: Department of Neurology, First Affiliated Hospital of China Medical University. MATERIALS: Five male 2-3-week-old Sprague Dawley rats were purchased from Animal Laboratory Center of China Medical University and included in this study. The protocol was performed in accordance with ethical guidelines for the use and care of animals. The microglial cell line BV2 was produced by Cell Research Institute of Chinese Academy of Sciences. LPS was produced by Sigma Company, USA. METHODS: This study was performed in the Central Laboratory of China Medical University from September 2006 to March 2007. Rat femoral and tibial bone marrow was collected for separation and primary culture of bone marrow mesenchymal stem cells. Bone marrow mesenchymal stem cell cultures were divided into 5 groups: control group, non-activated group, as well as low-, medium-, and high-dose LPS groups. In the control group, bone marrow mesenchymal stem cells were cultured with Dulbecco's modified Eagle's medium (DMEM) supplemented with fetal bovine serum (volume fraction 0.1). In the non-activated group, bone marrow mesenchymal stem cells were incubated with non-activated BV2 supernatant. In the low-, medium-, and high-dose LPS groups, bone marrow mesenchymal stem cells were incubated with LPS (0.01, 0.1 and 1

  4. Early neurodegeneration progresses independently of microglial activation by heparan sulfate in the brain of mucopolysaccharidosis IIIB mice.

    Directory of Open Access Journals (Sweden)

    Jérôme Ausseil

    Full Text Available BACKGROUND: In mucopolysaccharidosis type IIIB, a lysosomal storage disease causing early onset mental retardation in children, the production of abnormal oligosaccharidic fragments of heparan sulfate is associated with severe neuropathology and chronic brain inflammation. We addressed causative links between the biochemical, pathological and inflammatory disorders in a mouse model of this disease. METHODOLOGY/PRINCIPAL FINDINGS: In cell culture, heparan sulfate oligosaccharides activated microglial cells by signaling through the Toll-like receptor 4 and the adaptor protein MyD88. CD11b positive microglial cells and three-fold increased expression of mRNAs coding for the chemokine MIP1alpha were observed at 10 days in the brain cortex of MPSIIIB mice, but not in MPSIIIB mice deleted for the expression of Toll-like receptor 4 or the adaptor protein MyD88, indicating early priming of microglial cells by heparan sulfate oligosaccharides in the MPSIIIB mouse brain. Whereas the onset of brain inflammation was delayed for several months in doubly mutant versus MPSIIIB mice, the onset of disease markers expression was unchanged, indicating similar progression of the neurodegenerative process in the absence of microglial cell priming by heparan sulfate oligosaccharides. In contrast to younger mice, inflammation in aged MPSIIIB mice was not affected by TLR4/MyD88 deficiency. CONCLUSIONS/SIGNIFICANCE: These results indicate priming of microglia by HS oligosaccharides through the TLR4/MyD88 pathway. Although intrinsic to the disease, this phenomenon is not a major determinant of the neurodegenerative process. Inflammation may still contribute to neurodegeneration in late stages of the disease, albeit independent of TLR4/MyD88. The results support the view that neurodegeneration is primarily cell autonomous in this pediatric disease.

  5. Downregulation of NO and PGE2 in LPS-stimulated BV2 microglial cells by trans-isoferulic acid via suppression of PI3K/Akt-dependent NF-κB and activation of Nrf2-mediated HO-1.

    Science.gov (United States)

    Dilshara, Matharage Gayani; Lee, Kyoung-Tae; Jayasooriya, Rajapaksha Gedara Prasad Tharanga; Kang, Chang-Hee; Park, Sang Rul; Choi, Yung Hyun; Choi, Il-Whan; Hyun, Jin-Won; Chang, Weon-Young; Kim, Yeon-Su; Lee, Hak-Ju; Kim, Gi-Young

    2014-01-01

    Little is known about whether trans-isoferulic acid (TIA) regulates the production of lipopolysaccharide (LPS)-induced proinflammatory mediators. Therefore, we examined the effect of TIA isolated from Clematis mandshurica on LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production in BV2 microglial cells. We found that TIA inhibited the production of LPS-induced NO and PGE2 without accompanying cytotoxicity in BV2 microglial cells. TIA also downregulated the expression levels of specific regulatory genes such as inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) by suppressing LPS-induced NF-κB activity via dephosphorylation of PI3K/Akt. In addition, we demonstrated that a specific NF-κB inhibitor PDTC and a selective PI3K/Akt inhibitor, LY294002 effectively attenuated the expression of LPS-stimulated iNOS and COX-2 mRNA, while LY294002 suppressed LPS-induced NF-κB activity, suggesting that TIA attenuates the expression of these proinflammatory genes by suppressing PI3K/Akt-mediated NF-κB activity. Our results showed that TIA suppressed NO and PGE2 production through the induction of nuclear factor erythroid 2-related factor 2 (Nrf2)-dependent heme oxygenase-1 (HO-1). Taken together, our data indicate that TIA suppresses the production of proinflammatory mediators such as NO and PGE2, as well as their regulatory genes, in LPS-stimulated BV2 microglial cells, by inhibiting PI3K/Akt-dependent NF-κB activity and enhancing Nrf2-mediated HO-1 expression. PMID:24291391

  6. Crocin Upregulates CX3CR1 Expression by Suppressing NF-κB/YY1 Signaling and Inhibiting Lipopolysaccharide-Induced Microglial Activation.

    Science.gov (United States)

    Lv, Bochang; Huo, Fuquan; Zhu, Zhongqiao; Xu, Zhiguo; Dang, Xiaojie; Chen, Tao; Zhang, Ting; Yang, Xinguang

    2016-08-01

    Glaucoma is a group of neurodegenerative diseases characterized by the progressive loss of retinal ganglion cells (RGCs) and optic nerve fibers. Microglial activation has been shown to be deleterious to RGCs and may participate in the progression of glaucoma. Crocin, one of the major active ingredients in saffron, has been found to inhibit microglial activation. However, the mechanism remains unclear. The aim of this study was to investigate whether crocin can inhibit lipopolysaccharide (LPS)-induced microglial activation and to clarify the mechanisms involved. The influence of crocin on primary RGCs and LPS-stimulated BV2 microglial cells survival was determined by the MTT and lactate dehydrogenase assays, or by flow cytometry. BV2 cells were pretreated with various concentrations of crocin for 2 h followed by 1 μg/mL LPS stimulation. Microglial markers and pro-inflammatory mediators were assessed by real-time PCR, western blot and ELISA. Furthermore, CX3CR1 expression was detected and the underlying mechanism was examined. The concentrations of crocin ranged from 0.1 to 1 μM, and did not show any cytotoxicity in RGC and BV2 cells. After crocin pretreatment, the expression of microglial markers (CD11b and Iba-1) and pro-inflammatory mediators (iNOS, COX-2, IL-1β, and TNF-α) induced by LPS were significantly decreased in a dose-dependent manner. Additionally, CX3CR1 expression was remarkably increased by crocin via the suppression of NF-κB/Yin Yang 1 (YY1) signaling in BV2 cells. In conclusion, crocin effectively suppresses microglial activation and upregulates CX3CR1 expression by suppressing NF-κB/YY1 signaling. PMID:27084772

  7. Gabapentin reduces CX3CL1 signaling and blocks spinal microglial activation in monoarthritic rats

    Directory of Open Access Journals (Sweden)

    Yang Jia-Le

    2012-05-01

    Full Text Available Abstract Background Spinal glia, particularly microglia and astrocytes, are of the utmost importance in the development and maintenance of chronic pain. A recent study from our laboratory revealed that gabapentin, a recommended first-line treatment for multiple neuropathic conditions, could also efficiently antagonize thermal hyperalgesia evoked by complete Freund's adjuvant (CFA-induced monoarthritis (MA. In the present study, we investigated whether the spinal glia are involved in the anti-hyperalgesic effect of gabapentin and how this event occurs. Results Unilateral intra-articular injection of CFA produced a robust activation of microglia and astrocytes. These cells exhibited large cell bodies, thick processes and increases in the ionized calcium binding adapter molecule 1 (Iba-1, a microglial marker or the glia fibrillary acidic protein (GFAP, an astrocytic marker. These cells also displayed immunoreactive signals, and an upregulation of the voltage-gated calcium channels (VGCCs α2/δ-1 subunit, CX3CL1 and CX3CR1 expression levels in the spinal cord. These changes were associated with the development of thermal hyperalgesia. Immunofluorescence staining showed that VGCC α2/δ-1 subunit, a proposed gabapentin target of action, was widely distributed in primary afferent fibers terminals and dorsal horn neurons. CX3CL1, a potential trigger to activate microglia, colocalized with VGCC α2/δ-1 subunits in the spinal dorsal horn. However, its receptor CX3CR1 was mainly expressed in the spinal microglia. Multiple intraperitoneal (i.p. gabapentin injections (100 mg/kg, once daily for 4 days with the first injection 60 min before intra-articular CFA suppressed the activation of spinal microglia, downregulated spinal VGCC α2/δ-1 subunits decreased CX3CL1 levels and blocked the development of thermal hyperalgesia in MA rats. Conclusions Here we provide the first evidence that gabapentin diminishes CX3CL1 signaling and spinal microglia

  8. 线粒体分裂蛋白抑制剂对小胶质细胞氧化损伤的保护作用%Mitochondrial Division Inhibition Attenuates Aβ-induced Oxidative Stress Injury in Primary Microglial Cells

    Institute of Scientific and Technical Information of China (English)

    谢南昌; 陈晨; 王翠; 张倩; 夏建华; 张宏伟; 连亚军

    2014-01-01

    Objective:To investigate whether mitochondrial division inhibitor 1 (mdivi-1) attenuates β-amyloid protein (Aβ)-induced oxidative stress injury in primary microglial cells. Methods:Primary microglial cells were randomly divided into control group, Aβgroup, mdivi-1 group and Aβ+mdivi-1 group. The viability and apoptosis of cells, mitochondrial membrane potential, malondialdehyde (MDA) content, superoxide dismutase (SOD) content and 8-hydroxy-deoxyguanosine (8-OHdG) were examined. Results:Compared with control group, the cell viability of Aβ group was significantly reduced, the apoptotic cells was increased, the mitochondrial membrane potential and SOD activity were decreased, while the levels of MDA and 8-OHdG were increased( <0.05). Compared with the Aβgroup, in the Aβ+mdivi-1 group, the cell viability was increased, the apoptotic cells was decreased, the mitochondrial membrane potential and SOD activity were increased, while the levels of MDA and 8-OhdG were decreased ( <0.05). Conclusion:Mdivi-1 exerts neuroprotective effects against Aβ-induced oxida-tive stress injury in primary microglial cells.%目的:研究线粒体分裂蛋白抑制剂(mdivi-1)能否减轻β淀粉样蛋白(Aβ)诱导的体外原代培养小鼠小胶质细胞的氧化应激损伤。方法:随机将体外原代培养BALB/C小鼠小胶质细胞分为con组、Aβ组、mdi组和 Aβ+mdi 组,con 组不予处理,Aβ组中加入 Aβ,mdi 组中加入 mdivi-1,Aβ+mdi 组分别加入2、5、10、20μmol/L mdivi-1后1 h加入Aβ。分别检测小胶质细胞存活率及凋亡、线粒体膜电位、丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性、8-羟基脱氧鸟苷(8-OHdG)含量。结果:与con组相比,Aβ组小胶质细胞存活率下降,凋亡增加,线粒体膜电位下降,MDA和8-OHdG含量升高,SOD活性下降,差异有统计学意义(<0.05);与Aβ组相比,Aβ+mdi组小胶质细胞存活率上升,凋亡减少,线粒体

  9. Qingkailing Suppresses the Activation of BV2 Microglial Cells by Inhibiting Hypoxia/Reoxygenation-Induced Inflammatory Responses

    Directory of Open Access Journals (Sweden)

    Lulu Mana

    2014-01-01

    Full Text Available Qingkailing (QKL is a well-known composite extract used in traditional Chinese medicine. This extract has been extensively administered to treat the acute phase of cerebrovascular disease. Our previous experiments confirmed that QKL exerts an inhibitory effect on cerebral ischemia-induced inflammatory responses. However, whether QKL suppresses the activation of microglia, the primary resident immune cells in the brain, has yet to be determined. In this study, BV2 microglial cells were used to validate the protective effects of QKL treatment following ischemia-reperfusion injury simulated via hypoxia/reoxygenation in vitro. Under these conditions, high expression levels of ROS, COX-2, iNOS, and p-p38 protein were detected. Following ischemia/reperfusion injury, QKL significantly increased the activity of BV2 cells to approximately the basal level by modulating microglial activation via inhibition of inflammatory factors, including TNF-α, COX-2, iNOS, and p-p38. However, QKL treatment also displayed dose-dependent differences in its inhibitory effects on p38 phosphorylation and inflammatory factor expression.

  10. TLR4 mutation reduces microglial activation, increases Aβ deposits and exacerbates cognitive deficits in a mouse model of Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Song Min

    2011-08-01

    Full Text Available Abstract Background Amyloid plaques, a pathological hallmark of Alzheimer's disease (AD, are accompanied by activated microglia. The role of activated microglia in the pathogenesis of AD remains controversial: either clearing Aβ deposits by phagocytosis or releasing proinflammatory cytokines and cytotoxic substances. Microglia can be activated via toll-like receptors (TLRs, a class of pattern-recognition receptors in the innate immune system. We previously demonstrated that an AD mouse model homozygous for a loss-of-function mutation of TLR4 had increases in Aβ deposits and buffer-soluble Aβ in the brain as compared with a TLR4 wild-type AD mouse model at 14-16 months of age. However, it is unknown if TLR4 signaling is involved in initiation of Aβ deposition as well as activation and recruitment of microglia at the early stage of AD. Here, we investigated the role of TLR4 signaling and microglial activation in early stages using 5-month-old AD mouse models when Aβ deposits start. Methods Microglial activation and amyloid deposition in the brain were determined by immunohistochemistry in the AD models. Levels of cerebral soluble Aβ were determined by ELISA. mRNA levels of cytokines and chemokines in the brain and Aβ-stimulated monocytes were quantified by real-time PCR. Cognitive functions were assessed by the Morris water maze. Results While no difference was found in cerebral Aβ load between AD mouse models at 5 months with and without TLR4 mutation, microglial activation in a TLR4 mutant AD model (TLR4M Tg was less than that in a TLR4 wild-type AD model (TLR4W Tg. At 9 months, TLR4M Tg mice had increased Aβ deposition and soluble Aβ42 in the brain, which were associated with decrements in cognitive functions and expression levels of IL-1β, CCL3, and CCL4 in the hippocampus compared to TLR4W Tg mice. TLR4 mutation diminished Aβ-induced IL-1β, CCL3, and CCL4 expression in monocytes. Conclusion This is the first demonstration of TLR4

  11. Disruption of Fractalkine Signaling Leads to Microglial Activation and Neuronal Damage in the Diabetic Retina

    Directory of Open Access Journals (Sweden)

    Sandra M. Cardona

    2015-10-01

    Full Text Available Fractalkine (CX3CL1 or FKN is a membrane-bound chemokine expressed on neuronal membranes and is proteolytically cleaved to shed a soluble chemoattractant domain. FKN signals via its unique receptor CX3CR1 expressed on microglia and other peripheral leukocytes. The aim of this study is to determine the role of CX3CR1 in inflammatory-mediated damage to retinal neurons using a model of diabetic retinopathy. For this, we compared neuronal, microglial, and astroglial densities and inflammatory response in nondiabetic and diabetic (Ins2Akita CX3CR1-wild-type and CX3CR1-deficient mice at 10 and 20 weeks of age. Our results show that Ins2Akita CX3CR1-knockout mice exhibited (a decreased neuronal cell counts in the retinal ganglion cell layer, (b increased microglial cell numbers, and (c decreased astrocyte responses comparable with Ins2Akita CX3CR1-Wild-type mice at 20 weeks of age. Analyses of the inflammatory response using PCR arrays showed several inflammatory genes differentially regulated in diabetic tissues. From those, the response in Ins2Akita CX3CR1-deficient mice at 10 weeks of age revealed a significant upregulation of IL-1β at the transcript level that was confirmed by enzyme-linked immunosorbent assay in soluble retinal extracts. Overall, IL-1β, VEGF, and nitrite levels as a read out of nitric oxide production were abundant in Ins2Akita CX3CR1-deficient retina. Notably, double immunofluorescence staining shows that astrocytes act as a source of IL-1β in the Ins2Akita retina, and CX3CR1-deficient microglia potentiate the inflammatory response via IL-1β release. Collectively, these data demonstrate that dysregulated microglial responses in absence of CX3CR1 contribute to inflammatory-mediated damage of neurons in the diabetic retina.

  12. Krüppel-like factor 4, a novel transcription factor regulates microglial activation and subsequent neuroinflammation

    Directory of Open Access Journals (Sweden)

    Das Sulagna

    2010-10-01

    Full Text Available Abstract Background Activation of microglia, the resident macrophages of the central nervous system (CNS, is the hallmark of neuroinflammation in neurodegenerative diseases and other pathological conditions associated with CNS infection. The activation of microglia is often associated with bystander neuronal death. Nuclear factor-κB (NF-κB is one of the important transcription factors known to be associated with microglial activation which upregulates the expression of inducible nitric oxide synthase (iNOS, cyclooxygenase-2 (Cox-2 and other pro-inflammatory cytokines. Recent studies have focused on the role of Krüppel-like factor 4 (Klf4, one of the zinc-finger transcription factors, in mediating inflammation. However, these studies were limited to peripheral system and its role in CNS is not understood. Our studies focused on the possible role of Klf4 in mediating CNS inflammation. Methods For in vitro studies, mouse microglial BV-2 cell lines were treated with 500 ng/ml Salmonella enterica lipopolysacchride (LPS. Brain tissues were isolated from BALB/c mice administered with 5 mg/kg body weight of LPS. Expressions of Klf4, Cox-2, iNOS and pNF-κB were evaluated using western blotting, quantitative real time PCR, and reverse transcriptase polymerase chain reactions (RT-PCRs. Klf4 knockdown was carried out using SiRNA specific for Klf4 mRNA and luciferase assays and electromobility shift assay (EMSA were performed to study the interaction of Klf4 to iNOS promoter elements in vitro. Co-immunoprecipitation of Klf4 and pNF-κB was done in order to study a possible interaction between the two transcription factors. Results LPS stimulation increased Klf4 expression in microglial cells in a time- and dose-dependent manner. Knockdown of Klf4 resulted in decreased levels of the pro-inflammatory cytokines TNF-α, MCP-1 and IL-6, along with a significant decrease in iNOS and Cox-2 expression. NO production also decreased as a result of Klf4 knockdown

  13. In vivo changes in microglial activation and amyloid deposits in brain regions with hypometabolism in Alzheimer's disease

    Energy Technology Data Exchange (ETDEWEB)

    Yokokura, Masamichi; Mori, Norio; Yoshihara, Yujiro; Wakuda, Tomoyasu; Takebayashi, Kiyokazu; Iwata, Yasuhide; Nakamura, Kazuhiko [Hamamatsu University School of Medicine, Department of Psychiatry and Neurology, Hamamatsu (Japan); Yagi, Shunsuke; Ouchi, Yasuomi [Hamamatsu University School of Medicine, Laboratory of Human Imaging Research, Molecular Imaging Frontier Research Center, Hamamatsu (Japan); Yoshikawa, Etsuji [Hamamatsu Photonics K.K., Central Research Laboratory, Hamamatsu (Japan); Kikuchi, Mitsuru [Kanazawa University, Department of Psychiatry and Neurobiology, Graduate School of Medical Science, Kanazawa (Japan); Sugihara, Genichi; Suda, Shiro; Tsuchiya, Kenji J.; Suzuki, Katsuaki [Hamamatsu University School of Medicine, Research Center for Child Mental Development, Hamamatsu (Japan); Ueki, Takatoshi [Hamamatsu University School of Medicine, Department of Anatomy, Hamamatsu (Japan)

    2011-02-15

    Amyloid {beta} protein (A{beta}) is known as a pathological substance in Alzheimer's disease (AD) and is assumed to coexist with a degree of activated microglia in the brain. However, it remains unclear whether these two events occur in parallel with characteristic hypometabolism in AD in vivo. The purpose of the present study was to clarify the in vivo relationship between A{beta} accumulation and neuroinflammation in those specific brain regions in early AD. Eleven nootropic drug-naive AD patients underwent a series of positron emission tomography (PET) measurements with [{sup 11}C](R)PK11195, [{sup 11}C]PIB and [{sup 18}F]FDG and a battery of cognitive tests within the same day. The binding potentials (BPs) of [{sup 11}C](R)PK11195 were directly compared with those of [{sup 11}C]PIB in the brain regions with reduced glucose metabolism. BPs of [{sup 11}C](R)PK11195 and [{sup 11}C]PIB were significantly higher in the parietotemporal regions of AD patients than in ten healthy controls. In AD patients, there was a negative correlation between dementia score and [{sup 11}C](R)PK11195 BPs, but not [{sup 11}C]PIB, in the limbic, precuneus and prefrontal regions. Direct comparisons showed a significant negative correlation between [{sup 11}C](R)PK11195 and [{sup 11}C]PIB BPs in the posterior cingulate cortex (PCC) (p < 0.05, corrected) that manifested the most severe reduction in [{sup 18}F]FDG uptake. A lack of coupling between microglial activation and amyloid deposits may indicate that A{beta} accumulation shown by [{sup 11}C]PIB is not always the primary cause of microglial activation, but rather the negative correlation present in the PCC suggests that microglia can show higher activation during the production of A{beta} in early AD. (orig.)

  14. Microglial activation induced by factor(s) contained in sera from Alzheimer-related ApoE genotypes.

    Science.gov (United States)

    Lombardi, V R; García, M; Cacabelos, R

    1998-11-15

    Several factors that increase the likelihood of developing Alzheimer's disease (AD) have already been identified. A correct evaluation of these may contribute to a better understanding of the etiology of the disease. The risk of developing AD definitely increases with (a) age, (b) head injuries, (c) family history of AD or Down syndrome, (d) sex (higher prevalence of AD in women), (e) vascular disease, (f) exposure to environmental toxins, (g) infectious processes, or (h) changes in immune function, and recent advances in molecular genetics have suggested that genetic predisposition (i) can be considered one of the most important risk factors in the development of AD. A significant increase in the number of amyloid plaques in AD patients with an apolipoprotein E4 (ApoE) allele has been observed and the results of several genetic studies indicate that the etiology of this neurodegenerative disease is associated with the presence of the allele E4 of ApoE. A potential source of damage in the AD brain is an altered response triggered by microglial activation, which is associated with amyloid plaques. It has become evident that a dysregulation of cytokine release appears within lesions of many types of brain disorders including infection, trauma, stroke, and neurodegenerative diseases. Many studies have shown that microglia secrete both cytokines and cytotoxins and since reactive microglia appears in nearly every type of brain damage, it is likely that their secreted products ultimately help to determine the rate of damaged brain tissue. In this study, in vitro cell cultures were established to investigate the effect of different concentrations of human sera (2.5% and 10%) with specific ApoE genotypes from Alzheimer's and non-Alzheimer's subjects on ameboid and flat microglial cells obtained from neonatal rat hippocampi. Results show that a modulation in the proliferation and activation of microglial cells was obtained and that AD sera, mainly in the ApoE 3/4 and 4

  15. Depression as a microglial disease.

    Science.gov (United States)

    Yirmiya, Raz; Rimmerman, Neta; Reshef, Ronen

    2015-10-01

    Despite decades of intensive research, the biological mechanisms that causally underlie depression are still unclear, and therefore the development of novel effective antidepressant treatments is hindered. Recent studies indicate that impairment of the normal structure and function of microglia, caused by either intense inflammatory activation (e.g., following infections, trauma, stroke, short-term stress, autoimmune or neurodegenerative diseases) or by decline and senescence of these cells (e.g., during aging, Alzheimer's disease, or chronic unpredictable stress exposure), can lead to depression and associated impairments in neuroplasticity and neurogenesis. Accordingly, some forms of depression can be considered as a microglial disease (microgliopathy), which should be treated by a personalized medical approach using microglial inhibitors or stimulators depending on the microglial status of the depressed patient. PMID:26442697

  16. 3,4,5-Trihydroxycinnamic Acid Inhibits Lipopolysaccharide-Induced Inflammatory Response through the Activation of Nrf2 Pathway in BV2 Microglial Cells

    OpenAIRE

    Lee, Jae-Won; Choi, Yong-Jun; Park, Jun-Ho; Sim, Jae-Young; Kwon, Yong-Soo; Lee, Hee Jae; Kim, Sung-Soo; Chun, Wanjoo

    2013-01-01

    3,4,5-Trihydroxycinnamic acid (THC) is a derivative of hydroxycinnamic acids, which have been reported to possess a variety of biological properties such as anti-inflammatory, anti-tumor, and neuroprotective activities. However, biological activity of THC has not been extensively examined. Recently, we reported that THC possesses anti-inflammatory activity in LPS-stimulated BV2 microglial cells. However, its precise mechanism by which THC exerts anti-inflammatory action has not been clearly i...

  17. 3,4,5-Trihydroxycinnamic Acid Inhibits LPS-Induced iNOS Expression by Suppressing NF-κB Activation in BV2 Microglial Cells

    OpenAIRE

    Lee, Jae-Won; Bae, Chang Jun; Choi, Yong-Jun; Kim, Song-In; Kim, Nam-Ho; Lee, Hee Jae; Kim, Sung-Soo; Kwon, Yong-Soo; Chun, Wanjoo

    2012-01-01

    Although various derivatives of caffeic acid have been reported to possess a wide variety of biological activities such as neuronal protection against excitotoxicity and anti-inflammatory property, the biological activity of 3,4,5-trihydroxycinnamic acid (THC), a derivative of hydroxycinnamic acids, has not been clearly examined. The objective of the present study is to evaluate the anti-inflammatory effects of THC on lipopolysaccharide (LPS)-stimulated BV2 microglial cells. THC significantly...

  18. COX-2, CB2 and P2X7-immunoreactivities are increased in activated microglial cells/macrophages of multiple sclerosis and amyotrophic lateral sclerosis spinal cord

    Directory of Open Access Journals (Sweden)

    Bountra Chas

    2006-03-01

    Full Text Available Abstract Background While multiple sclerosis (MS and amyotrophic lateral sclerosis (ALS are primarily inflammatory and degenerative disorders respectively, there is increasing evidence for shared cellular mechanisms that may affect disease progression, particularly glial responses. Cyclooxygenase 2 (COX-2 inhibition prolongs survival and cannabinoids ameliorate progression of clinical disease in animal models of ALS and MS respectively, but the mechanism is uncertain. Therefore, three key molecules known to be expressed in activated microglial cells/macrophages, COX-2, CB2 and P2X7, which plays a role in inflammatory cascades, were studied in MS and ALS post-mortem human spinal cord. Methods Frozen human post mortem spinal cord specimens, controls (n = 12, ALS (n = 9 and MS (n = 19, were available for study by immunocytochemistry and Western blotting, using specific antibodies to COX-2, CB2 and P2X7, and markers of microglial cells/macrophages (CD 68, ferritin. In addition, autoradiography for peripheral benzodiazepine binding sites was performed on some spinal cord sections using [3H] (R-PK11195, a marker of activated microglial cells/macrophages. Results of immunostaining and Western blotting were quantified by computerized image and optical density analysis respectively. Results In control spinal cord, few small microglial cells/macrophages-like COX-2-immunoreactive cells, mostly bipolar with short processes, were scattered throughout the tissue, whilst MS and ALS specimens had significantly greater density of such cells with longer processes in affected regions, by image analysis. Inflammatory cell marker CD68-immunoreactivity, [3H] (R-PK11195 autoradiography, and double-staining against ferritin confirmed increased production of COX-2 by activated microglial cells/macrophages. An expected 70-kDa band was seen by Western blotting which was significantly increased in MS spinal cord. There was good correlation between the COX-2 immunostaining

  19. Hypoxia induced amoeboid microglial cell activation in postnatal rat brain is mediated by ATP receptor P2X4

    Directory of Open Access Journals (Sweden)

    Li Fan

    2011-11-01

    Full Text Available Abstract Background Activation of amoeboid microglial cells (AMC and its related inflammatory response have been linked to the periventricular white matter damage after hypoxia in neonatal brain. Hypoxia increases free ATP in the brain and then induces various effects through ATP receptors. The present study explored the possible mechanism in ATP induced AMC activation in hypoxia. Results We first examined the immunoexpression of P2X4, P2X7 and P2Y12 in the corpus callosum (CC and subependyma associated with the lateral ventricles where both areas are rich in AMC. Among the three purinergic receptors, P2X4 was most intensely expressed. By double immunofluorescence, P2X4 was specifically localized in AMC (from P0 to P7 but the immunofluorescence in AMC was progressively diminished with advancing age (P14. It was further shown that P2X4 expression was noticeably enhanced in P0 day rats subjected to hypoxia and killed at 4, 24, 72 h and 7 d versus their matching controls by double labeling and western blotting analysis. P2X4 expression was most intense at 7 d whence the inflammatory response was drastic after hypoxia. We then studied the association of P2X4 with cytokine release in AMC after hypoxic exposure. In primary microglial cells exposed to hypoxia, IL-1β and TNF-α protein levels were up-regulated. Blockade of P2X4 receptor with 2', 3'-0-(2, 4, 6-Trinitrophenyl adenosine 5'-triphosphate, a selective P2X1-7 blocker resulted in partial suppression of IL-1β (24% vs hypoxic group and TNF-α expression (40% vs hypoxic group. However, pyridoxal phosphate-6-azo (benzene-2, 4-disulfonic acid tetrasodium salt hydrate, a selective P2X1-3, 5-7 blocker did not exert any significant effect on the cytokine expression. Conclusions It is concluded that P2X4 which is constitutively expressed by AMC in postnatal rats was enhanced in hypoxia. Hypoxia induced increase in IL-1β and TNF-α expression was reversed by 2', 3'-0-(2, 4, 6-Trinitrophenyl adenosine

  20. Anti-Inflammatory Activity of Bee Venom in BV2 Microglial Cells: Mediation of MyD88-Dependent NF-κB Signaling Pathway

    OpenAIRE

    Im, Eun Ju; Kim, Su Jung; Hong, Seung Bok; PARK, Jin-Kyu; Rhee, Man Hee

    2016-01-01

    Bee venom has long been used as a traditional folk medicine in Korea. It has been reportedly used for the treatment of arthritis, cancer, and inflammation. Although its anti-inflammatory activity in lipopolysaccharide- (LPS-) stimulated inflammatory cells has been reported, the exact mechanism of its anti-inflammatory action has not been fully elucidated. Therefore, the aim of this study was to investigate the anti-inflammatory mechanism of bee venom in BV2 microglial cells. We first investig...

  1. Lipopolysaccharide-induced microglial activation and neuroprotection against experimental brain injury is independent of hematogenous TLR4.

    Science.gov (United States)

    Chen, Zhihong; Jalabi, Walid; Shpargel, Karl B; Farabaugh, Kenneth T; Dutta, Ranjan; Yin, Xinghua; Kidd, Grahame J; Bergmann, Cornelia C; Stohlman, Stephen A; Trapp, Bruce D

    2012-08-22

    Intraperitoneal injection of the Gram-negative bacterial endotoxin lipopolysaccharide (LPS) elicits a rapid innate immune response. While this systemic inflammatory response can be destructive, tolerable low doses of LPS render the brain transiently resistant to subsequent injuries. However, the mechanism by which microglia respond to LPS stimulation and participate in subsequent neuroprotection has not been documented. In this study, we first established a novel LPS treatment paradigm where mice were injected intraperitoneally with 1.0 mg/kg LPS for four consecutive days to globally activate CNS microglia. By using a reciprocal bone marrow transplantation procedure between wild-type and Toll-like receptor 4 (TLR4) mutant mice, we demonstrated that the presence of LPS receptor (TLR4) is not required on hematogenous immune cells but is required on cells that are not replaced by bone marrow transplantation, such as vascular endothelia and microglia, to transduce microglial activation and neuroprotection. Furthermore, we showed that activated microglia physically ensheathe cortical projection neurons, which have reduced axosomatic inhibitory synapses from the neuronal perikarya. In line with previous reports that inhibitory synapse reduction protects neurons from degeneration and injury, we show here that neuronal cell death and lesion volumes are significantly reduced in LPS-treated animals following experimental brain injury. Together, our results suggest that activated microglia participate in neuroprotection and that this neuroprotection is likely achieved through reduction of inhibitory axosomatic synapses. The therapeutic significance of these findings rests not only in identifying neuroprotective functions of microglia, but also in establishing the CNS location of TLR4 activation. PMID:22915113

  2. Curcumin is a potent modulator of microglial gene expression and migration

    Directory of Open Access Journals (Sweden)

    Aslanidis Alexander

    2011-09-01

    Signal transducer and activator of transcription 1 was reduced in LPS-triggered microglia. These transcriptional changes in curcumin-treated LPS-primed microglia also lead to decreased neurotoxicity with reduced apoptosis of 661W photoreceptor cultures. Conclusions Collectively, our results suggest that curcumin is a potent modulator of the microglial transcriptome. Curcumin attenuates microglial migration and triggers a phenotype with anti-inflammatory and neuroprotective properties. Thus, curcumin could be a nutraceutical compound to develop immuno-modulatory and neuroprotective therapies for the treatment of various neurodegenerative disorders.

  3. Low-level laser therapy regulates microglial function through Src-mediated signaling pathways: implications for neurodegenerative diseases

    Directory of Open Access Journals (Sweden)

    Song Sheng

    2012-09-01

    Full Text Available Abstract Background Activated microglial cells are an important pathological component in brains of patients with neurodegenerative diseases. The purpose of this study was to investigate the effect of He-Ne (632.8 nm, 64.6 mW/cm2 low-level laser therapy (LLLT, a non-damaging physical therapy, on activated microglia, and the subsequent signaling events of LLLT-induced neuroprotective effects and phagocytic responses. Methods To model microglial activation, we treated the microglial BV2 cells with lipopolysaccharide (LPS. For the LLLT-induced neuroprotective study, neuronal cells with activated microglial cells in a Transwell™ cell-culture system were used. For the phagocytosis study, fluorescence-labeled microspheres were added into the treated microglial cells to confirm the role of LLLT. Results Our results showed that LLLT (20 J/cm2 could attenuate toll-like receptor (TLR-mediated proinflammatory responses in microglia, characterized by down-regulation of proinflammatory cytokine expression and nitric oxide (NO production. LLLT-triggered TLR signaling inhibition was achieved by activating tyrosine kinases Src and Syk, which led to MyD88 tyrosine phosphorylation, thus impairing MyD88-dependent proinflammatory signaling cascade. In addition, we found that Src activation could enhance Rac1 activity and F-actin accumulation that typify microglial phagocytic activity. We also found that Src/PI3K/Akt inhibitors prevented LLLT-stimulated Akt (Ser473 and Thr308 phosphorylation and blocked Rac1 activity and actin-based microglial phagocytosis, indicating the activation of Src/PI3K/Akt/Rac1 signaling pathway. Conclusions The present study underlines the importance of Src in suppressing inflammation and enhancing microglial phagocytic function in activated microglia during LLLT stimulation. We have identified a new and important neuroprotective signaling pathway that consists of regulation of microglial phagocytosis and inflammation under LLLT

  4. Anandamide, Acting via CB2 Receptors, Alleviates LPS-Induced Neuroinflammation in Rat Primary Microglial Cultures

    Directory of Open Access Journals (Sweden)

    Natalia Malek

    2015-01-01

    Full Text Available Microglial activation is a polarized process divided into potentially neuroprotective phenotype M2 and neurotoxic phenotype M1, predominant during chronic neuroinflammation. Endocannabinoid system provides an attractive target to control the balance between microglial phenotypes. Anandamide as an immune modulator in the central nervous system acts via not only cannabinoid receptors (CB1 and CB2 but also other targets (e.g., GPR18/GPR55. We studied the effect of anandamide on lipopolysaccharide-induced changes in rat primary microglial cultures. Microglial activation was assessed based on nitric oxide (NO production. Analysis of mRNA was conducted for M1 and M2 phenotype markers possibly affected by the treatment. Our results showed that lipopolysaccharide-induced NO release in microglia was significantly attenuated, with concomitant downregulation of M1 phenotypic markers, after pretreatment with anandamide. This effect was not sensitive to CB1 or GPR18/GPR55 antagonism. Administration of CB2 antagonist partially abolished the effects of anandamide on microglia. Interestingly, administration of a GPR18/GPR55 antagonist by itself suppressed NO release. In summary, we showed that the endocannabinoid system plays a crucial role in the management of neuroinflammation by dampening the activation of an M1 phenotype. This effect was primarily controlled by the CB2 receptor, although functional cross talk with GPR18/GPR55 may occur.

  5. Cytomegalovirus Infection of the Rat Developing Brain In Utero Prominently Targets Immune Cells and Promotes Early Microglial Activation

    Science.gov (United States)

    Cloarec, Robin; Bauer, Sylvian; Luche, Hervé; Buhler, Emmanuelle; Pallesi-Pocachard, Emilie; Salmi, Manal; Courtens, Sandra; Massacrier, Annick; Grenot, Pierre; Teissier, Natacha; Watrin, Françoise; Schaller, Fabienne; Adle-Biassette, Homa; Gressens, Pierre; Malissen, Marie; Stamminger, Thomas; Streblow, Daniel N.; Bruneau, Nadine; Szepetowski, Pierre

    2016-01-01

    Background Congenital cytomegalovirus infections are a leading cause of neurodevelopmental disorders in human and represent a major health care and socio-economical burden. In contrast with this medical importance, the pathophysiological events remain poorly known. Murine models of brain cytomegalovirus infection, mostly neonatal, have brought recent insights into the possible pathogenesis, with convergent evidence for the alteration and possible involvement of brain immune cells. Objectives and Methods In order to confirm and expand those findings, particularly concerning the early developmental stages following infection of the fetal brain, we have created a model of in utero cytomegalovirus infection in the developing rat brain. Rat cytomegalovirus was injected intraventricularly at embryonic day 15 (E15) and the brains analyzed at various stages until the first postnatal day, using a combination of gene expression analysis, immunohistochemistry and multicolor flow cytometry experiments. Results Rat cytomegalovirus infection was increasingly seen in various brain areas including the choroid plexi and the ventricular and subventricular areas and was prominently detected in CD45low/int, CD11b+ microglial cells, in CD45high, CD11b+ cells of the myeloid lineage including macrophages, and in CD45+, CD11b– lymphocytes and non-B non-T cells. In parallel, rat cytomegalovirus infection of the developing rat brain rapidly triggered a cascade of pathophysiological events comprising: chemokines upregulation, including CCL2-4, 7 and 12; infiltration by peripheral cells including B-cells and monocytes at E17 and P1, and T-cells at P1; and microglia activation at E17 and P1. Conclusion In line with previous findings in neonatal murine models and in human specimen, our study further suggests that neuroimmune alterations might play critical roles in the early stages following cytomegalovirus infection of the brain in utero. Further studies are now needed to determine which

  6. Statins attenuate polymethylmethacrylate-mediated monocyte activation.

    LENUS (Irish Health Repository)

    Laing, Alan J

    2012-02-03

    BACKGROUND: Periprosthetic osteolysis precipitates aseptic loosening of components, increases the risk of periprosthetic fracture and, through massive bone loss, complicates revision surgery and ultimately is the primary cause for failure of joint arthroplasty. The anti-inflammatory properties of HMG-CoA reductase inhibitors belonging to the statin family are well recognized. We investigated a possible role for status in initiating the first stage of the osteolytic cycle, namely monocytic activation. METHODS: We used an in vitro model of the human monocyte\\/macrophage inflammatory response to poly-methylmethacrylate (PMMA) particles after pretreat-ing cells with cerivastatin, a potent member of the statin family. Cell activation based upon production of TNF-alpha and MCP-1 cytokines was analyzed and the intracellular Raf-MEK-ERK signal transduction pathway was evaluated using western blot analysis, to identify its role in cell activation and in any cerivastatin effects observed. RESULTS: We found that pretreatment with cerivastatin significantly abrogates the production of inflammatory cytokines TNF-alpha and MCP-1 by human monocytes in response to polymethylmethacrylate particle activation. This inflammatory activation and attenuation appear to be mediated through the intracellular Raf-MEK-ERK pathway. INTERPRETATION: We propose that by intervening at the upstream activation stage, subsequent osteoclast activation and osteolysis can be suppressed. We believe that the anti-inflammatory properties of statins may potentially play a prophylactic role in the setting of aseptic loosening, and in so doing increase implant longevity.

  7. Suppressed Microglial E Prostanoid Receptor 1 Signaling Selectively Reduces TNFα and IL-6 Secretion from Toll-like Receptor 3 Activation

    Science.gov (United States)

    Li, Xianwu; Cudaback, Eiron; Keene, C. Dirk; Breyer, Richard M.; Montine, Thomas J.

    2010-01-01

    Activation of innate immunity via Toll-like receptors (TLRs) is associated with neurodegenerative diseases, and some effectors, like tumor necrosis factor alpha (TNFα) and interleukin 6 (IL-6), directly contribute to neurodegeneration. We tested the hypothesis that prostaglandin (PG) E2 receptor subtype 1 (EP1) was necessary for induction of microglial cytokines following activation of innate immunity. Primary murine microglia had cytokine secretion by activators of TLR3 > TLR9 >TLR4 > TLR2. TLR3 activation induced early expression of cyclooxygenase 2 (COX2) and delayed expression of membranous PGE synthase and secretion of PGE2. Non-selective and COX2-selective inhibitors blocked TLR3 induction of TNFα and IL-6. Moreover, of the eight out of twenty cytokines and chemokines induced by TLR3 activation, only TNFα and IL-6 were significantly dependent on EP1 signaling as determined using microglia from mice homozygous deficient for EP1 gene or wild type (WT) microglia co-incubated with an EP1 antagonist. These results were confirmed by blocking intracellular Ca2+ release with 2-aminoethoxy-diphenyl borate (2-APB) or Xestospongin C (XC), inhibitors of IP3 receptors. Our results show that suppression of microglial EP1 signaling achieves much of the desired effect of COX inhibitors by selectively blocking TLR3-induced microglial secretion of two major effectors of paracrine neuron damage. In combination with the ability of EP1 suppression to ameliorate excitotoxicity, these data point to blockade of EP1 as an attractive candidate therapeutic for neurodegenerative diseases. PMID:21319223

  8. Preventive effects of a fermented dairy product against Alzheimer's disease and identification of a novel oleamide with enhanced microglial phagocytosis and anti-inflammatory activity.

    Directory of Open Access Journals (Sweden)

    Yasuhisa Ano

    Full Text Available Despite the ever-increasing number of patients with dementia worldwide, fundamental therapeutic approaches to this condition have not been established. Epidemiological studies suggest that intake of fermented dairy products prevents cognitive decline in the elderly. However, the active compounds responsible for the effect remain to be elucidated. The present study aims to elucidate the preventive effects of dairy products on Alzheimer's disease and to identify the responsible component. Here, in a mouse model of Alzheimer's disease (5xFAD, intake of a dairy product fermented with Penicillium candidum had preventive effects on the disease by reducing the accumulation of amyloid β (Aβ and hippocampal inflammation (TNF-α and MIP-1α production, and enhancing hippocampal neurotrophic factors (BDNF and GDNF. A search for preventive substances in the fermented dairy product identified oleamide as a novel dual-active component that enhanced microglial Aβ phagocytosis and anti-inflammatory activity towards LPS stimulation in vitro and in vivo. During the fermentation, oleamide was synthesized from oleic acid, which is an abundant component of general dairy products owing to lipase enzymatic amidation. The present study has demonstrated the preventive effect of dairy products on Alzheimer's disease, which was previously reported only epidemiologically. Moreover, oleamide has been identified as an active component of dairy products that is considered to reduce Aβ accumulation via enhanced microglial phagocytosis, and to suppress microglial inflammation after Aβ deposition. Because fermented dairy products such as camembert cheese are easy to ingest safely as a daily meal, their consumption might represent a preventive strategy for dementia.

  9. Preventive effects of a fermented dairy product against Alzheimer's disease and identification of a novel oleamide with enhanced microglial phagocytosis and anti-inflammatory activity.

    Science.gov (United States)

    Ano, Yasuhisa; Ozawa, Makiko; Kutsukake, Toshiko; Sugiyama, Shinya; Uchida, Kazuyuki; Yoshida, Aruto; Nakayama, Hiroyuki

    2015-01-01

    Despite the ever-increasing number of patients with dementia worldwide, fundamental therapeutic approaches to this condition have not been established. Epidemiological studies suggest that intake of fermented dairy products prevents cognitive decline in the elderly. However, the active compounds responsible for the effect remain to be elucidated. The present study aims to elucidate the preventive effects of dairy products on Alzheimer's disease and to identify the responsible component. Here, in a mouse model of Alzheimer's disease (5xFAD), intake of a dairy product fermented with Penicillium candidum had preventive effects on the disease by reducing the accumulation of amyloid β (Aβ) and hippocampal inflammation (TNF-α and MIP-1α production), and enhancing hippocampal neurotrophic factors (BDNF and GDNF). A search for preventive substances in the fermented dairy product identified oleamide as a novel dual-active component that enhanced microglial Aβ phagocytosis and anti-inflammatory activity towards LPS stimulation in vitro and in vivo. During the fermentation, oleamide was synthesized from oleic acid, which is an abundant component of general dairy products owing to lipase enzymatic amidation. The present study has demonstrated the preventive effect of dairy products on Alzheimer's disease, which was previously reported only epidemiologically. Moreover, oleamide has been identified as an active component of dairy products that is considered to reduce Aβ accumulation via enhanced microglial phagocytosis, and to suppress microglial inflammation after Aβ deposition. Because fermented dairy products such as camembert cheese are easy to ingest safely as a daily meal, their consumption might represent a preventive strategy for dementia. PMID:25760987

  10. CX3CL1 reduces neurotoxicity and microglial activation in a rat model of Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Hudson Charles E

    2011-01-01

    Full Text Available Abstract Background Parkinson's disease is characterized by a progressive loss of dopaminergic neurons in the substantia nigra. The cause of the neurodegeneration is unknown. Neuroinflammation has been clearly shown in Parkinson's disease and may be involved in the progressive nature of the disease. Microglia are capable of producing neuronal damage through the production of bioactive molecules such as cytokines, as well as reactive oxygen species (ROS, and nitric oxide (NO. The inflammatory response in the brain is tightly regulated at multiple levels. One form of immune regulation occurs via neurons. Fractalkine (CX3CL1, produced by neurons, suppresses the activation of microglia. CX3CL1 is constitutively expressed. It is not known if addition of exogenous CX3CL1 beyond otherwise physiologically normal levels could decrease microglia activation and thereby minimize the secondary neurodegeration following a neurotoxic insult. Methods The intrastriatal 6-hydroxydopamine (6-OHDA rat model of Parkinson disease, was used to test the hypothesis that exogenous CX3CL1 could be neuroprotective. Treatment with recombinant CX3CL1 was delivered to the striatum by an osmotic minipump for 28 days beginning 7 days after the initial insult. Unbiased stereological methods were used to quantify the lesion size in the striatum, the amount of neuronal loss in the substantia nigra, and the amount of microglia activation. Results As hypothesized, CX3CL1 was able to suppress this microglia activation. The reduced microglia activation was found to be neuroprotective as the CX3CL1 treated rats had a smaller lesion volume in the striatum and importantly significantly fewer neurons were lost in the CX3CL1 treated rats. Conclusion These findings demonstrated that CX3CL1 plays a neuroprotective role in 6-OHDA-induced dopaminergic lesion and it might be an effective therapeutic target for many neurodegenerative diseases, including Parkinson disease and Alzheimer disease

  11. GDNF selectively induces microglial activation and neuronal survival in CA1/CA3 hippocampal regions exposed to NMDA insult through Ret/ERK signalling.

    Directory of Open Access Journals (Sweden)

    Francesca Boscia

    Full Text Available The glial cell line-derived neurotrophic factor (GDNF is a potent survival factor for several neuronal populations in different brain regions, including the hippocampus. However, no information is available on the: (1 hippocampal subregions involved in the GDNF-neuroprotective actions upon excitotoxicity, (2 identity of GDNF-responsive hippocampal cells, (3 transduction pathways involved in the GDNF-mediated neuroprotection in the hippocampus. We addressed these questions in organotypic hippocampal slices exposed to GDNF in presence of N-methyl-D-aspartate (NMDA by immunoblotting, immunohistochemistry, and confocal analysis. In hippocampal slices GDNF acts through the activation of the tyrosine kinase receptor, Ret, without involving the NCAM-mediated pathway. Both Ret and ERK phosphorylation mainly occurred in the CA3 region where the two activated proteins co-localized. GDNF protected in a greater extent CA3 rather than CA1 following NMDA exposure. This neuroprotective effect targeted preferentially neurons, as assessed by NeuN staining. GDNF neuroprotection was associated with a significant increase of Ret phosphorylation in both CA3 and CA1. Interestingly, confocal images revealed that upon NMDA exposure, Ret activation occurred in microglial cells in the CA3 and CA1 following GDNF exposure. Collectively, this study shows that CA3 and CA1 hippocampal regions are highly responsive to GDNF-induced Ret activation and neuroprotection, and suggest that, upon excitotoxicity, such neuroprotection involves a GDNF modulation of microglial cell activity.

  12. Peripheral and Central Effects of Repeated Social Defeat Stress: Monocyte Trafficking, Microglial Activation, and Anxiety

    Science.gov (United States)

    Reader, Brenda F.; Jarrett, Brant L.; McKim, Daniel B.; Wohleb, Eric S.; Godbout, Jonathan P.; Sheridan, John F.

    2015-01-01

    The development and exacerbation of depression and anxiety are associated with exposure to repeated psychosocial stress. Stress is known to affect the bidirectional communication between the nervous and immune systems leading to elevated levels of stress mediators including glucocorticoids (GCs) and catecholamines and increased trafficking of proinflammatory immune cells. Animal models, like the repeated social defeat (RSD) paradigm, were developed to explore this connection between stress and affective disorders. RSD induces activation of the sympathetic nervous system (SNS) and hypothalamic-pituitary (HPA) axis activation, increases bone marrow production and egress of primed, GC-insensitive monocytes, and stimulates the trafficking of these cells to tissues including the spleen, lung, and brain. Recently, the observation that these monocytes have the ability to traffic to the brain perivascular spaces and parenchyma have provided mechanisms by which these peripheral cells may contribute to the prolonged anxiety-like behavior associated with RSD. The data that have been amassed from the RSD paradigm and others recapitulate many of the behavioral and immunological phenotypes associated with human anxiety disorders and may serve to elucidate potential avenues of treatment for these disorders. Here, we will discuss novel and key data that will present an overview of the neuroendocrine, immunological and behavioral responses to social stressors. PMID:25596319

  13. Inhibition of Src kinase activity attenuates amyloid associated microgliosis in a murine model of Alzheimer’s disease

    Directory of Open Access Journals (Sweden)

    Dhawan Gunjan

    2012-07-01

    Full Text Available Abstract Background Microglial activation is an important histologic characteristic of the pathology of Alzheimer’s disease (AD. One hypothesis is that amyloid beta (Aβ peptide serves as a specific stimulus for tyrosine kinase-based microglial activation leading to pro-inflammatory changes that contribute to disease. Therefore, inhibiting Aβ stimulation of microglia may prove to be an important therapeutic strategy for AD. Methods Primary murine microglia cultures and the murine microglia cell line, BV2, were used for stimulation with fibrillar Aβ1-42. The non-receptor tyrosine kinase inhibitor, dasatinib, was used to treat the cells to determine whether Src family kinase activity was required for the Aβ stimulated signaling response and subsequent increase in TNFα secretion using Western blot analysis and enzyme-linked immunosorbent assay (ELISA, respectively. A histologic longitudinal analysis was performed using an AD transgenic mouse model, APP/PS1, to determine an age at which microglial protein tyrosine kinase levels increased in order to administer dasatinib via mini osmotic pump diffusion. Effects of dasatinib administration on microglial and astroglial activation, protein phosphotyrosine levels, active Src kinase levels, Aβ plaque deposition, and spatial working memory were assessed via immunohistochemistry, Western blot, and T maze analysis. Results Aβ fibrils stimulated primary murine microglia via a tyrosine kinase pathway involving Src kinase that was attenuated by dasatinib. Dasatinib administration to APP/PS1 mice decreased protein phosphotyrosine, active Src, reactive microglia, and TNFα levels in the hippocampus and temporal cortex. The drug had no effect on GFAP levels, Aβ plaque load, or the related tyrosine kinase, Lyn. These anti-inflammatory changes correlated with improved performance on the T maze test in dasatinib infused animals compared to control animals. Conclusions These data suggest that amyloid

  14. TAM receptors affect adult brain neurogenesis by negative regulation of microglial cell activation.

    Science.gov (United States)

    Ji, Rui; Tian, Shifu; Lu, Helen J; Lu, Qingjun; Zheng, Yan; Wang, Xiaomin; Ding, Jixiang; Li, Qiutang; Lu, Qingxian

    2013-12-15

    TAM tyrosine kinases play multiple functional roles, including regulation of the target genes important in homeostatic regulation of cytokine receptors or TLR-mediated signal transduction pathways. In this study, we show that TAM receptors affect adult hippocampal neurogenesis and loss of TAM receptors impairs hippocampal neurogenesis, largely attributed to exaggerated inflammatory responses by microglia characterized by increased MAPK and NF-κB activation and elevated production of proinflammatory cytokines that are detrimental to neuron stem cell proliferation and neuronal differentiation. Injection of LPS causes even more severe inhibition of BrdU incorporation in the Tyro3(-/-)Axl(-/-)Mertk(-/-) triple-knockout (TKO) brains, consistent with the LPS-elicited enhanced expression of proinflammatory mediators, for example, IL-1β, IL-6, TNF-α, and inducible NO synthase, and this effect is antagonized by coinjection of the anti-inflammatory drug indomethacin in wild-type but not TKO brains. Conditioned medium from TKO microglia cultures inhibits neuron stem cell proliferation and neuronal differentiation. IL-6 knockout in Axl(-/-)Mertk(-/-) double-knockout mice overcomes the inflammatory inhibition of neurogenesis, suggesting that IL-6 is a major downstream neurotoxic mediator under homeostatic regulation by TAM receptors in microglia. Additionally, autonomous trophic function of the TAM receptors on the proliferating neuronal progenitors may also promote progenitor differentiation into immature neurons.

  15. Novel point mutations attenuate autotaxin activity

    Directory of Open Access Journals (Sweden)

    Stracke Mary L

    2009-02-01

    Full Text Available Abstract Background The secreted enzyme autotaxin (ATX stimulates tumor cell migration, tumorigenesis, angiogenesis, and metastasis. ATX hydrolyzes nucleotides, but its hydrolysis of lysophospholipids to produce lysophosphatidic acid (LPA accounts for its biological activities. ATX has been identified only as a constitutively active enzyme, and regulation of its activity is largely unexplored. In spite of its presence in plasma along with abundant putative substrate LPC, the product LPA is found in plasma at unexpectedly low concentrations. It is plausible that the LPA-producing activity of ATX is regulated by its expression and by access to substrate(s. For this reason studying the interaction of enzyme with substrate is paramount to understanding the regulation of LPA production. Results In this study we determine ATX hydrolytic activities toward several artificial and natural substrates. Two novel point mutations near the enzyme active site (H226Q and H434Q confer attenuated activity toward all substrates tested. The Vmax for LPC compounds depends upon chain length and saturation; but this order does not differ among wild type and mutants. However the mutant forms show disproportionately low activity toward two artificial substrates, pNpTMP and FS-3. The mutant forms did not significantly stimulate migration responses at concentrations that produced a maximum response for WT-ATX, but this defect could be rescued by inclusion of exogenous LPC. Conclusion H226Q-ATX and H434Q-ATX are the first point mutations of ATX/NPP2 demonstrated to differentially impair substrate hydrolysis, with hydrolysis of artificial substrates being disproportionately lower than that of LPC. This implies that H226 and H434 are important for substrate interaction. Assays that rely on hydrolyses of artificial substrates (FS-3 and pNpTMP, or that rely on hydrolysis of cell-derived substrate, might fail to detect certain mutated forms of ATX that are nonetheless capable of

  16. N-[3,4-dimethoxycinnamoyl]-anthranilic acid (tranilast) suppresses microglial inducible nitric oxide synthase (iNOS) expression and activity induced by interferon-γ (IFN-γ)

    OpenAIRE

    Platten, Michael; Wick, Wolfgang; Wischhusen, Jörg; WELLER, MICHAEL

    2001-01-01

    Microglial cells up-regulate inducible nitric oxide synthase (iNOS) expression in response to various pro-inflammatory stimuli including interferon-γ (IFN-γ), allowing for the release of nitric oxide (NO). Tranilast (N-[3,4-dimethoxycinnamoyl]-anthranilic acid) is an antiallergic compound with suppressive effects on the activation of monocytes.Here, we show that N9 murine microglial cells express iNOS mRNA and protein and release nitric oxide into the culture medium in response to IFN-γ (200 ...

  17. Fibrillar beta-amyloid peptide Aβ1–40 activates microglial proliferation via stimulating TNF-α release and H2O2 derived from NADPH oxidase: a cell culture study

    Directory of Open Access Journals (Sweden)

    Sharpe Martyn

    2006-09-01

    Full Text Available Abstract Background Alzheimer's disease is characterized by the accumulation of neuritic plaques, containing activated microglia and β-amyloid peptides (Aβ. Fibrillar Aβ can activate microglia, resulting in production of toxic and inflammatory mediators like hydrogen peroxide, nitric oxide, and cytokines. We have recently found that microglial proliferation is regulated by hydrogen peroxide derived from NADPH oxidase. Thus, in this study, we investigated whether Aβ can stimulate microglial proliferation and cytokine production via activation of NADPH oxidase to produce hydrogen peroxide. Methods Primary mixed glial cultures were prepared from the cerebral cortices of 7-day-old Wistar rats. At confluency, microglial cells were isolated by tapping, replated, and treated either with or without Aβ. Hydrogen peroxide production by cells was measured with Amplex Red and peroxidase. Microglial proliferation was assessed under a microscope 0, 24 and 48 hours after plating. TNF-α and IL-1β levels in the culture medium were assessed by ELISA. Results We found that 1 μM fibrillar (but not soluble Aβ1–40 peptide induced microglial proliferation and caused release of hydrogen peroxide, TNF-α and IL-1β from microglial cells. Proliferation was prevented by the NADPH oxidase inhibitor apocynin (10 μM, by the hydrogen peroxide-degrading enzyme catalase (60 U/ml, and by its mimetics EUK-8 and EUK-134 (20 μM; as well as by an antibody against TNF-α and by a soluble TNF receptor inhibitor. Production of TNF-α and IL-1β, measured after 24 hours of Aβ treatment, was also prevented by apocynin, catalase and EUKs, but the early release (measured after 1 hour of Aβ treatment of TNF-α was insensitive to apocynin or catalase. Conclusion These results indicate that Aβ1–40-induced microglial proliferation is mediated both by microglial release of TNF-α and production of hydrogen peroxide from NADPH oxidase. This suggests that TNF-α and NADPH

  18. Proinflammatory-activated glioma cells induce a switch in microglial polarization and activation status, from a predominant M2b phenotype to a mixture of M1 and M2a/B polarized cells

    Directory of Open Access Journals (Sweden)

    Lucia Lisi

    2014-05-01

    Full Text Available Malignant gliomas are primary brain tumors characterized by morphological and genetic complexities, as well as diffuse infiltration into normal brain parenchyma. Within gliomas, microglia/macrophages represent the largest tumor-infiltrating cell population, contributing by at least one-third to the total tumor mass. Bi-directional interactions between glioma cells and microglia may therefore play an important role on tumor growth and biology. In the present study, we have characterized the influence of glioma-soluble factors on microglial function, comparing the effects of media harvested under basal conditions with those of media obtained after inducing a pro-inflammatory activation state in glioma cells. We found that microglial cells undergo a different pattern of activation depending on the stimulus; in the presence of activated glioma-derived factors, i.e. a condition mimicking the late stage of pathology, microglia presents as a mixture of polarization phenotypes (M1 and M2a/b, with up-regulation of iNOS (inducible nitric oxide synthase, ARG (arginase and IL (interleukine-10. At variance, microglia exposed to basal glioma-derived factors, i.e. a condition resembling the early stage of pathology, shows a more specific pattern of activation, with increased M2b polarization status and up-regulation of IL-10 only. As far as viability and cell proliferation are concerned, both LI-CM [LPS (lipopolysaccharide–IFNγ (interferon γ conditioned media] and C-CM (control-conditioned media induce similar effects on microglial morphology. Finally, in human glioma tissue obtained from surgical resection of patients with IV grade glioblastoma, we detected a significant amount of CD68 positive cells, which is a marker of macrophage/microglial phagocytic activity, suggesting that in vitro findings presented here might have a relevance in the human pathology as well.

  19. Evaluation of CLINDE as potent translocator protein (18 kDa) SPECT radiotracer reflecting the degree of neuroinflammation in a rat model of microglial activation

    Energy Technology Data Exchange (ETDEWEB)

    Arlicot, Nicolas; Duval, Stephanie; Guilloteau, Denis; Chalon, Sylvie [Inserm, U930, Tours (France); Universite Francois Rabelais, Tours (France); CHRU de Tours, Tours (France); Katsifis, Andrew; Mattner, Filomena [Australian Nuclear Science and Technology Organisation, Radiopharmaceuticals Research Institute, Sydney (Australia); Garreau, Lucette; Vergote, Jackie; Bodard, Sylvie [Inserm, U930, Tours (France); Universite Francois Rabelais, Tours (France)

    2008-12-15

    The translocator protein (TSPO; 18 kDa), the new name of the peripheral-type benzodiazepine receptor, is localised in mitochondria of glial cells and expressed in very low concentrations in normal brain. Their expression rises after microglial activation following brain injury. Accordingly, TSPO are potential targets to evaluate neuroinflammatory changes in a variety of CNS disorders. To date, only a few effective tools are available to explore TSPO by SPECT. We characterised here 6-chloro-2-(4'iodophenyl)-3-(N,N-diethyl)-imidazo[1,2-a]pyridine-3-acetamide or CLINDE in a rat model with different stages of excitotoxic lesion. Excitotoxicity was induced in male Wistar rats by unilateral intrastriatal injection of different amounts of quinolinic acid (75, 150 or 300 nmol). Six days later, two groups of rats (n = 5-6/group) were i.v. injected with [{sup 125}I]-CLINDE (0.4 MBq); one group being pre-injected with PK11195 (5 mg/kg). Brains were removed 30 min after tracer injection and the radioactivity of cerebral areas measured. Complementary ex vivo autoradiography, in vitro autoradiography ([{sup 3}H]-PK11195) and immunohistochemical studies (OX-42) were performed on brain sections. In the control group, [{sup 125}I]-CLINDE binding was significantly higher (p < 0.001) in lesioned than that in intact side. This binding disappeared in rats pre-treated with PK11195 (p<0.001), showing specific binding of CLINDE to TSPO. Ex vivo and in vitro autoradiographic studies and immunohistochemistry were consistent with this, revealing a spatial correspondence between radioactivity signal and activated microglia. Regression analysis yielded a positive relation between the ligand binding and the degree of neuroinflammation. These results demonstrate that CLINDE is suitable for TSPO in vivo SPECT imaging to explore their involvement in neurodegenerative disorders associated with microglial activation. (orig.)

  20. Inhibition of Src kinase activity attenuates amyloid associated microgliosis in a murine model of Alzheimer’s disease

    OpenAIRE

    Dhawan Gunjan; Combs Colin K

    2012-01-01

    Abstract Background Microglial activation is an important histologic characteristic of the pathology of Alzheimer’s disease (AD). One hypothesis is that amyloid beta (Aβ) peptide serves as a specific stimulus for tyrosine kinase-based microglial activation leading to pro-inflammatory changes that contribute to disease. Therefore, inhibiting Aβ stimulation of microglia may prove to be an important therapeutic strategy for AD. Methods Primary murine microglia cultures and the murine microglia c...

  1. GBE50 Attenuates Inflammatory Response by Inhibiting the p38 MAPK and NF-κB Pathways in LPS-Stimulated Microglial Cells

    Directory of Open Access Journals (Sweden)

    Gai-ying He

    2014-01-01

    Full Text Available Overactivated microglia contribute to a variety of pathological conditions in the central nervous system. The major goal of the present study is to evaluate the potential suppressing effects of a new type of Ginko biloba extract, GBE50, on activated microglia which causes proinflammatory responses and to explore the underlying molecular mechanisms. Murine BV2 microglia cells, with or without pretreatmentof GBE50 at various concentrations, were activated by incubation with lipopolysaccharide (LPS. A series of biochemical and microscopic assays were performed to measure cell viability, cell morphology, release of tumor necrosis factor-α (TNF-α and interleukin-1β (IL-1β, and signal transduction via the p38 MAPK and nuclear factor-kappa B (NF-κB p65 pathways. We found that GBE50 pretreatment suppressed LPS-induced morphological changes in BV2 cells. Moreover, GBE50 treatment significantly reduced the release of proinflammatory cytokines, TNF-α and IL-1β, and inhibited the associated signal transduction through the p38 MAPK and NF-κB p65 pathways. These results demonstrated the anti-inflammatory effect of GBE50 on LPS-activated BV2 microglia cells, and indicated that GBE50 reduced the LPS-induced proinflammatory TNF-α and IL-1β release by inhibiting signal transduction through the NF-κB p65 and p38 MAPK pathways. Our findings reveal, at least in part, the molecular basis underlying the anti-inflammatory effects of GBE50.

  2. The PPAR-γ Agonist 15-Deoxy-Δ12,14-Prostaglandin J2 Attenuates Microglial Production of IL-12 Family Cytokines: Potential Relevance to Alzheimer's Disease

    Directory of Open Access Journals (Sweden)

    Jihong Xu

    2008-01-01

    Full Text Available Accumulation of amyloid-β peptide (Aβ appears to contribute to the pathogenesis of Alzheimer's disease (AD. Therapeutic hope for the prevention or removal of Aβ deposits has been placed in strategies involving immunization against the Aβ peptide. Initial Aβ immunization studies in animal models of AD showed great promise. However, when this strategy was attempted in human subjects with AD, an unacceptable degree of meningoencephalitis occurred. It is generally believed that this adverse outcome resulted from a T-cell response to Aβ. Specifically, CD4+ Th1 and Th17 cells may contribute to severe CNS inflammation and limit the utility of Aβ immunization in the treatment of AD. Interleukin (IL-12 and IL-23 play critical roles in the development of Th1 and Th17 cells, respectively. In the present study, Aβ1−42 synergistically elevated the expression of IL-12 and IL-23 triggered by inflammatory activation of microglia, and the peroxisome proliferator-activated receptor (PPAR-γ agonist 15-deoxy-Δ12,14-PGJ2 (15d-PGJ2 effectively blocked the elevation of these proinflammatory cytokines. Furthermore, 15d-PGJ2 suppressed the Aβ-related synergistic induction of CD14, MyD88, and Toll-like receptor 2, molecules that play critical roles in neuroinflammatory conditions. Collectively, these studies suggest that PPAR-γ agonists may be effective in modulating the development of AD.

  3. Small interfering RNA-mediated suppression of Ccl2 in Müller cells attenuates microglial recruitment and photoreceptor death following retinal degeneration

    Directory of Open Access Journals (Sweden)

    Rutar Matt

    2012-09-01

    Full Text Available Abstract Background The recruitment and activation of inflammatory cells is thought to exacerbate photoreceptor death in retinal degenerative conditions such as age-related macular degeneration (AMD. We investigated the role of Müller cell-derived chemokine (C-C motif ligand (Ccl2 expression on monocyte/microglia infiltration and photoreceptor death in light-mediated retinal degeneration, using targeted small interfering (siRNA. Methods Adult Sprague–Dawley rats were injected intravitreally with 1 μg of either Ccl2 siRNA or scrambled siRNA, and were then exposed to 1000 lux of light for a period of 24 hours. The mice were given an overdose of barbiturate, and the retinas harvested and evaluated for the effects of bright-light exposure. Ccl2 expression was assessed by quantitative PCR, immunohistochemistry, and in situ hybridization. Monocytes/microglia were counted on retinal cryostat sections immunolabeled with the markers ED1 and ionized calcium binding adaptor (IBA1, and photoreceptor apoptosis was assessed using terminal dUTP nick end labeling. Results Intravitreal injection of Ccl2 siRNA significantly reduced the expression of Ccl2 following light damage to 29% compared with controls. In retinas injected with Ccl2 siRNA, in situ hybridization and immunohistochemistry on retinal cryostat sections showed a substantial decrease in Ccl2 within Müller cells. Cell counts showed significantly fewer ED1-positive and IBA1-positive cells in the retinal vasculature and outer nuclear layer of Ccl2 siRNA-injected retinas, compared with controls. Moreover, there was significantly less photoreceptor apoptosis in Ccl2 siRNA-injected retinas compared with controls. Conclusions Our data indicate that Ccl2 expression by Müller cells promotes the infiltration of monocytes/microglia, thereby contributing to the neuroinflammatory response and photoreceptor death following retinal injury. Modulation of exaggerated chemokine responses using siRNA may have

  4. Detection and quantification of remote microglial activation in rodent models of focal ischaemia using the TSPO radioligand CLINDE

    Energy Technology Data Exchange (ETDEWEB)

    Arlicot, Nicolas [Universite Francois Rabelais de Tours, CHRU de Tours (France). UMR Inserm U 930, CNRS ERL 3106; UFR Sciences Pharmaceutiques, Laboratoire de Biophysique, Tours (France); Petit, Edwige; Toutain, Jerome; Divoux, Didier; Roussel, Simon; Bernaudin, Myriam [Universite de Caen Basse-Normandie, Universite Paris-Descartes, CNRS, CEA CYCERON, Caen (France). Equipe CERVOxy ' ' Hypoxie et Physiopathologie cerebrovasculaire' ' , UMR 6232 CI-NAPS; Katsifis, Andrew [ANSTO, Radiopharmaceuticals Research Institute, Menai (Australia); Bodard, Sylvie; Guilloteau, Denis; Chalon, Sylvie [Universite Francois Rabelais de Tours, CHRU de Tours (France). UMR Inserm U 930, CNRS ERL 3106

    2010-12-15

    Neuroinflammation is involved in stroke pathophysiology and might be imaged using radioligands targeting the 18 kDa translocator protein (TSPO). We studied microglial reaction in brain areas remote from the primary lesion site in two rodent models of focal cerebral ischaemia (permanent or transient) using [{sup 125}I]-CLINDE, a promising TSPO single photon emission computed tomography radioligand. In a mouse model of permanent middle cerebral artery occlusion (MCAO), ex vivo autoradiographic studies demonstrated, besides in the ischaemic territory, accumulation of [{sup 125}I]-CLINDE in the ipsilateral thalamus with a binding that progressed up to 3 weeks after MCAO. [{sup 125}I]-CLINDE binding markedly decreased in animals pre-injected with either unlabelled CLINDE or PK11195, while no change was observed with flumazenil pre-treatment, demonstrating TSPO specificity. In rats subjected to transient MCAO, [{sup 125}I]-CLINDE binding in the ipsilateral thalamus and substantia nigra pars reticulata (SNr) was significantly higher than that in contralateral tissue. Moreover, [{sup 125}I]-CLINDE binding in the thalamus and SNr was quantitatively correlated to the ischaemic volume assessed by MRI in the cortex and striatum, respectively. Clinical consequences of secondary neuronal degeneration in stroke might be better treated thanks to the discrimination of neuronal processes using in vivo molecular imaging and potent TSPO radioligands like CLINDE to guide therapeutic interventions. (orig.)

  5. Coordinated role of voltage-gated sodium channels and the Na{sup +}/H{sup +} exchanger in sustaining microglial activation during inflammation

    Energy Technology Data Exchange (ETDEWEB)

    Hossain, Muhammad M. [Department of Environmental and Occupational Medicine and Environmental and Occupational Health Sciences Institute, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ (United States); Sonsalla, Patricia K. [Department of Neurology, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ (United States); Richardson, Jason R., E-mail: jricha3@eohsi.rutgers.edu [Department of Environmental and Occupational Medicine and Environmental and Occupational Health Sciences Institute, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ (United States)

    2013-12-01

    Persistent neuroinflammation and microglial activation play an integral role in the pathogenesis of many neurological disorders. We investigated the role of voltage-gated sodium channels (VGSC) and Na{sup +}/H{sup +} exchangers (NHE) in the activation of immortalized microglial cells (BV-2) after lipopolysaccharide (LPS) exposure. LPS (10 and 100 ng/ml) caused a dose- and time-dependent accumulation of intracellular sodium [(Na{sup +}){sub i}] in BV-2 cells. Pre-treatment of cells with the VGSC antagonist tetrodotoxin (TTX, 1 μM) abolished short-term Na{sup +} influx, but was unable to prevent the accumulation of (Na{sup +}){sub i} observed at 6 and 24 h after LPS exposure. The NHE inhibitor cariporide (1 μM) significantly reduced accumulation of (Na{sup +}){sub i} 6 and 24 h after LPS exposure. Furthermore, LPS increased the mRNA expression and protein level of NHE-1 in a dose- and time-dependent manner, which was significantly reduced after co-treatment with TTX and/or cariporide. LPS increased production of TNF-α, ROS, and H{sub 2}O{sub 2} and expression of gp91{sup phox}, an active subunit of NADPH oxidase, in a dose- and time-dependent manner, which was significantly reduced by TTX or TTX + cariporide. Collectively, these data demonstrate a closely-linked temporal relationship between VGSC and NHE-1 in regulating function in activated microglia, which may provide avenues for therapeutic interventions aimed at reducing neuroinflammation. - Highlights: • LPS causes immediate increase in sodium through VGSC and subsequently through the NHE-1. • Inhibition of VGSC reduces increases in NHE-1 and gp91{sup phox}. • Inhibition of VGSC and NHE-1 reduces NADPH oxidase-mediated Tnf-α, ROS, and H{sub 2}O{sub 2} production. • NHE-1 and Na{sub v}1.6 may be viable targets for therapeutic interventions to reduce neuroinflammation in neurodegenerative disease.

  6. Novel point mutations attenuate autotaxin activity

    OpenAIRE

    Stracke Mary L; Roberts David D; Bandle Russell W; Koh Eunjin; Clair Timothy

    2009-01-01

    Abstract Background The secreted enzyme autotaxin (ATX) stimulates tumor cell migration, tumorigenesis, angiogenesis, and metastasis. ATX hydrolyzes nucleotides, but its hydrolysis of lysophospholipids to produce lysophosphatidic acid (LPA) accounts for its biological activities. ATX has been identified only as a constitutively active enzyme, and regulation of its activity is largely unexplored. In spite of its presence in plasma along with abundant putative substrate LPC, the product LPA is ...

  7. Inhibitory effect of a tyrosine-fructose Maillard reaction product, 2,4-bis(p-hydroxyphenyl-2-butenal on amyloid-β generation and inflammatory reactions via inhibition of NF-κB and STAT3 activation in cultured astrocytes and microglial BV-2 cells

    Directory of Open Access Journals (Sweden)

    Choi Im Seup

    2011-10-01

    Full Text Available Abstract Background Amyloidogenesis is linked to neuroinflammation. The tyrosine-fructose Maillard reaction product, 2,4-bis(p-hydroxyphenyl-2-butenal, possesses anti-inflammatory properties in cultured macrophages, and in an arthritis animal model. Because astrocytes and microglia are responsible for amyloidogenesis and inflammatory reactions in the brain, we investigated the anti-inflammatory and anti-amyloidogenic effects of 2,4-bis(p-hydroxyphenyl-2-butenal in lipopolysaccharide (LPS-stimulated astrocytes and microglial BV-2 cells. Methods Cultured astrocytes and microglial BV-2 cells were treated with LPS (1 μg/ml for 24 h, in the presence (1, 2, 5 μM or absence of 2,4-bis(p-hydroxyphenyl-2-butenal, and harvested. We performed molecular biological analyses to determine the levels of inflammatory and amyloid-related proteins and molecules, cytokines, Aβ, and secretases activity. Nuclear factor-kappa B (NF-κB DNA binding activity was determined using gel mobility shift assays. Results We found that 2,4-bis(p-hydroxyphenyl-2-butenal (1, 2, 5 μM suppresses the expression of inducible nitric oxide synthase (iNOS and cyclooxygenase-2 (COX-2 as well as the production of nitric oxide (NO, reactive oxygen species (ROS, tumor necrosis factor-α (TNF-α, and interleukin-1β (IL-1β in LPS (1 μg/ml-stimulated astrocytes and microglial BV-2 cells. Further, 2,4-bis(p-hydroxyphenyl-2-butenal inhibited the transcriptional and DNA binding activity of NF-κB--a transcription factor that regulates genes involved in neuroinflammation and amyloidogenesis via inhibition of IκB degradation as well as nuclear translocation of p50 and p65. Consistent with the inhibitory effect on inflammatory reactions, 2,4-bis(p-hydroxyphenyl-2-butenal inhibited LPS-elevated Aβ42 levels through attenuation of β- and γ-secretase activities. Moreover, studies using signal transducer and activator of transcription 3 (STAT3 siRNA and a pharmacological inhibitor showed that 2

  8. Glial Cell Line-Derived Neurotrophic Factor Family Members Reduce Microglial Activation via Inhibiting p38MAPKs-Mediated Inflammatory Responses

    Directory of Open Access Journals (Sweden)

    Uta Rickert

    2014-01-01

    Full Text Available Previous studies have shown that glial cell line-derived neurotrophic factor (GDNF family ligands (GFL are potent survival factors for dopaminergic neurons and motoneurons with therapeutic potential for Parkinson’s disease. However, little is known about direct influences of the GFL on microglia function, which are known to express part of the GDNF receptor system. Using RT-PCR and immunohistochemistrym we investigated the expression of the GDNF family receptor alpha 1 (GFR alpha and the coreceptor transmembrane receptor tyrosine kinase (RET in rat microglia in vitro as well as the effect of GFL on the expression of proinflammatory molecules in LPS activated microglia. We could show that GFL are able to regulate microglia functions and suggest that part of the well known neuroprotective action may be related to the suppression of microglial activation. We further elucidated the functional significance and pathophysiological implications of these findings and demonstrate that microglia are target cells of members of the GFL (GDNF and the structurally related neurotrophic factors neurturin (NRTN, artemin (ARTN, and persephin (PSPN.

  9. Importance of Attenuating Quadriceps Activation Deficits after Total Knee Arthroplasty

    OpenAIRE

    Thomas, Abbey C.; Jennifer E Stevens-Lapsley

    2012-01-01

    Total knee arthroplasty (TKA) is associated with persistent quadriceps dysfunction. Since quadriceps dysfunction impairs functional performance, minimizing quadriceps dysfunction by attenuating central activation deficits early after surgery may improve function later in life. Rehabilitation strategies incorporating neuromuscular electrical stimulation and early, aggressive quadriceps strengthening may prove beneficial. Further, surgical approaches such as minimally invasive TKA may minimize ...

  10. LRRK2 kinase inhibition prevents pathological microglial phagocytosis in response to HIV-1 Tat protein

    Directory of Open Access Journals (Sweden)

    Marker Daniel F

    2012-11-01

    Full Text Available Abstract Background Human Immunodeficiency Virus-1 (HIV-1 associated neurocognitive disorders (HANDs are accompanied by significant morbidity, which persists despite the use of combined antiretroviral therapy (cART. While activated microglia play a role in pathogenesis, changes in their immune effector functions, including phagocytosis and proinflammatory signaling pathways, are not well understood. We have identified leucine-rich repeat kinase 2 (LRRK2 as a novel regulator of microglial phagocytosis and activation in an in vitro model of HANDs, and hypothesize that LRRK2 kinase inhibition will attenuate microglial activation during HANDs. Methods We treated BV-2 immortalized mouse microglia cells with the HIV-1 trans activator of transcription (Tat protein in the absence or presence of LRRK2 kinase inhibitor (LRRK2i. We used Western blot, qRT-PCR, immunocytochemistry and latex bead engulfment assays to analyze LRRK2 protein levels, proinflammatory cytokine and phagocytosis receptor expression, LRRK2 cellular distribution and phagocytosis, respectively. Finally, we utilized ex vivo microfluidic chambers containing primary hippocampal neurons and BV-2 microglia cells to investigate microglial phagocytosis of neuronal axons. Results We found that Tat-treatment of BV-2 cells induced kinase activity associated phosphorylation of serine 935 on LRRK2 and caused the formation of cytoplasmic LRRK2 inclusions. LRRK2i decreased Tat-induced phosphorylation of serine 935 on LRRK2 and inhibited the formation of Tat-induced cytoplasmic LRRK2 inclusions. LRRK2i also decreased Tat-induced process extension in BV-2 cells. Furthermore, LRRK2i attenuated Tat-induced cytokine expression and latex bead engulfment. We examined relevant cellular targets in microfluidic chambers and found that Tat-treated BV-2 microglia cells cleared axonal arbor and engulfed neuronal elements, whereas saline treated controls did not. LRRK2i was found to protect axons in the presence

  11. Microglial Dysregulation in Psychiatric Disease

    Directory of Open Access Journals (Sweden)

    Luciana Romina Frick

    2013-01-01

    Full Text Available Microglia, the brain's resident immune cells, are phagocytes of the macrophage lineage that have a key role in responding to inflammation and immune challenge in the brain. More recently, they have been shown to have a number of important roles beyond immune surveillance and response, including synaptic pruning during development and the support of adult neurogenesis. Microglial abnormalities have been found in several neuropsychiatric conditions, though in most cases it remains unclear whether these are causative or are a reaction to some other underlying pathophysiology. Here we summarize postmortem, animal, neuroimaging, and other evidence for microglial pathology in major depression, schizophrenia, autism, obsessive-compulsive disorder, and Tourette syndrome. We identify gaps in the existing literature and important areas for future research. If microglial pathology proves to be an important causative factor in these or other neuropsychiatric diseases, modulators of microglial function may represent a novel therapeutic strategy.

  12. SENP1 inhibits the IH-induced apoptosis and nitric oxide production in BV2 microglial cells.

    Science.gov (United States)

    Liu, Song; Wang, Zhong-hua; Xu, Bo; Chen, Kui; Sun, Jin-yuan; Ren, Lian-ping

    2015-11-27

    To reveal SUMOylation and the roles of Sentrin-specific proteases (SENP)s in microglial cells under Intermittent hypoxia (IH) condition would provide more intensive view of understanding the mechanisms of IH-induced central nervous system (CNS) damage. Hence, in the present study, we detected the expression levels of SENPs in microglial cells under IH and normoxia conditions via RT-PCR assay. We found that SENP1 was significantly down-regulated in cells exposure to IH. Subsequently, the effect of IH for the activation of microglia and the potential roles of SENP1 in the SENP1-overexpressing cell lines were investigated via Western blotting, RT-PCR and Griess assay. The present study demonstrated the apoptosis-inducing and activating role of IH on microglia. In addition, we revealed that the effect of IH on BV-2 including apoptosis, nitric oxide synthase (iNOS) expression and nitric oxide (NO) induction can be attenuated by SENP1 overexpression. The results of the present study are of both theoretical and therapeutic significance to explore the potential roles of SENP1 under IH condition and elucidated the mechanisms underlying microglial survival and activation. PMID:26499079

  13. Cinnamon and Its Metabolite Sodium Benzoate Attenuate the Activation of p21rac and Protect Memory and Learning in an Animal Model of Alzheimer's Disease.

    Directory of Open Access Journals (Sweden)

    Khushbu K Modi

    Full Text Available This study underlines the importance of cinnamon, a commonly used natural spice and flavoring material, and its metabolite sodium benzoate (NaB in attenuating oxidative stress and protecting memory and learning in an animal model of Alzheimer's disease (AD. NaB, but not sodium formate, was found to inhibit LPS-induced production of reactive oxygen species (ROS in mouse microglial cells. Similarly, NaB also inhibited fibrillar amyloid beta (Aβ- and 1-methyl-4-phenylpyridinium(+-induced microglial production of ROS. Although NaB reduced the level of cholesterol in vivo in mice, reversal of the inhibitory effect of NaB on ROS production by mevalonate, and geranylgeranyl pyrophosphate, but not cholesterol, suggests that depletion of intermediates, but not end products, of the mevalonate pathway is involved in the antioxidant effect of NaB. Furthermore, we demonstrate that an inhibitor of p21rac geranylgeranyl protein transferase suppressed the production of ROS and that NaB suppressed the activation of p21rac in microglia. As expected, marked activation of p21rac was observed in the hippocampus of subjects with AD and 5XFAD transgenic (Tg mouse model of AD. However, oral feeding of cinnamon (Cinnamonum verum powder and NaB suppressed the activation of p21rac and attenuated oxidative stress in the hippocampus of Tg mice as evident by decreased dihydroethidium (DHE and nitrotyrosine staining, reduced homocysteine level and increased level of reduced glutathione. This was accompanied by suppression of neuronal apoptosis, inhibition of glial activation, and reduction of Aβ burden in the hippocampus and protection of memory and learning in transgenic mice. Therefore, cinnamon powder may be a promising natural supplement in halting or delaying the progression of AD.

  14. Attenuation of rodent neuropathic pain by an orally active peptide, RAP-103, which potently blocks CCR2- and CCR5-mediated monocyte chemotaxis and inflammation.

    Science.gov (United States)

    Padi, Satyanarayana S V; Shi, Xiang Q; Zhao, Yuan Q; Ruff, Michael R; Baichoo, Noel; Pert, Candace B; Zhang, Ji

    2012-01-01

    Chemokine signaling is important in neuropathic pain, with microglial cells expressing CCR2 playing a well-established key role. DAPTA, a HIV gp120-derived CCR5 entry inhibitor, has been shown to inhibit CCR5-mediated monocyte migration and to attenuate neuroinflammation. We report here that as a stabilized analog of DAPTA, the short peptide RAP-103 exhibits potent antagonism for both CCR2 (half maximal inhibitory concentration [IC50] 4.2 pM) and CCR5 (IC50 0.18 pM) in monocyte chemotaxis. Oral administration of RAP-103 (0.05-1 mg/kg) for 7 days fully prevents mechanical allodynia and inhibits the development of thermal hyperalgesia after partial ligation of the sciatic nerve in rats. Administered from days 8 to 12, RAP-103 (0.2-1 mg/kg) reverses already established hypersensitivity. RAP-103 relieves behavioral hypersensitivity, probably through either or both CCR2 and CCR5 blockade, because by using genetically deficient animals, we demonstrated that in addition to CCR2, CCR5 is also required for the development of neuropathic pain. Moreover, RAP-103 is able to reduce spinal microglial activation and monocyte infiltration, and to inhibit inflammatory responses evoked by peripheral nerve injury that cause chronic pain. Our findings suggest that targeting CCR2/CCR5 should provide greater efficacy than targeting CCR2 or CCR5 alone, and that dual CCR2/CCR5 antagonist RAP-103 has the potential for broad clinical use in neuropathic pain treatment.

  15. Minocycline Attenuates Neonatal Germinal-Matrix-Hemorrhage-Induced Neuroinflammation and Brain Edema by Activating Cannabinoid Receptor 2.

    Science.gov (United States)

    Tang, Jun; Chen, Qianwei; Guo, Jing; Yang, Liming; Tao, Yihao; Li, Lin; Miao, Hongping; Feng, Hua; Chen, Zhi; Zhu, Gang

    2016-04-01

    Germinal matrix hemorrhage (GMH) is the most common neurological disease of premature newborns leading to detrimental neurological sequelae. Minocycline has been reported to play a key role in neurological inflammatory diseases by controlling some mechanisms that involve cannabinoid receptor 2 (CB2R). The current study investigated whether minocycline reduces neuroinflammation and protects the brain from injury in a rat model of collagenase-induced GMH by regulating CB2R activity. To test this hypothesis, the effects of minocycline and a CB2R antagonist (AM630) were evaluated in male rat pups that were post-natal day 7 (P7) after GMH. We found that minocycline can lead to increased CB2R mRNA expression and protein expression in microglia. Minocycline significantly reduced GMH-induced brain edema, microglial activation, and lateral ventricular volume. Additionally, minocycline enhanced cortical thickness after injury. All of these neuroprotective effects of minocycline were prevented by AM630. A cannabinoid CB2 agonist (JWH133) was used to strengthen the hypothesis, which showed the identical neuroprotective effects of minocycline. Our study demonstrates, for the first time, that minocycline attenuates neuroinflammation and brain injury in a rat model of GMH, and activation of CBR2 was partially involved in these processes. PMID:25833102

  16. Systemic inflammation regulates microglial responses to tissue damage in vivo

    Science.gov (United States)

    Gyoneva, Stefka; Davalos, Dimitrios; Biswas, Dipankar; Swanger, Sharon A.; Garnier-Amblard, Ethel; Loth, Francis; Akassoglou, Katerina; Traynelis, Stephen F.

    2015-01-01

    Microglia, the resident immune cells of the central nervous system, exist in either a “resting” state associated with physiological tissue surveillance or an “activated” state in neuroinflammation. We recently showed that ATP is the primary chemoattractor to tissue damage in vivo and elicits opposite effects on the motility of activated microglia in vitro through activation of adenosine A2A receptors. However, whether systemic inflammation affects microglial responses to tissue damage in vivo remains largely unknown. Using in vivo two-photon imaging of mice, we show that injection of lipopolysaccharide (LPS) at levels that can produce both clear neuroinflammation and some features of sepsis significantly reduced the rate of microglial response to laser-induced ablation injury in vivo. Under pro-inflammatory conditions, microglial processes initially retracted from the ablation site, but subsequently moved toward and engulfed the damaged area. Analyzing the process dynamics in 3D cultures of primary microglia indicated that only A2A, but not A1 or A3 receptors, mediate process retraction in LPS-activated microglia. The A2A receptor antagonists caffeine and preladenant reduced adenosine-mediated process retraction in activated microglia in vitro. Finally, administration of preladenant before induction of laser ablation in vivo accelerated the microglial response to injury following systemic inflammation. The regulation of rapid microglial responses to sites of injury by A2A receptors could have implications for their ability to respond to the neuronal death occurring under conditions of neuroinflammation in neurodegenerative disorders. PMID:24807189

  17. Axonal lesion-induced microglial proliferation and microglial cluster formation in the mouse

    DEFF Research Database (Denmark)

    Dissing-Olesen, L; Ladeby, R; Nielsen, Helle Hvilsted;

    2007-01-01

    Microglia are innate immune cells and form the first line of defense of the CNS. Proliferation is a key event in the activation of microglia in acute pathology, and has been extensively characterized in rats, but not in mice. In this study we investigated axonal-lesion-induced microglial...... proliferation and surface antigen expression in C57BL/6 mice. Transection of the entorhino-dentate perforant path projection results in an anterograde axonal and a dense terminal degeneration that induces a region-specific activation of microglia in the dentate gyrus. Time-course analysis showed activation...... and the proliferation marker bromodeoxyuridine, injected 1 h prior to perfusion, showed that lesion-reactive microglia accounted for the vast majority of proliferating cells. Microglia proliferated as soon as 24 h after lesion and 25% of all microglial cells were proliferating 3 days post-lesion. Immunofluorescence...

  18. Attenuation of neuroinflammation by dexmedetomidine is associated with activation of a cholinergic anti-inflammatory pathway in a rat tibial fracture model.

    Science.gov (United States)

    Zhu, Ya-Juan; Peng, Ke; Meng, Xiao-Wen; Ji, Fu-Hai

    2016-08-01

    Sustained neuroinflammation contributes to the pathogenesis of postoperative cognitive dysfunction. Dexmedetomidine, a selective α-2 adrenergic receptor agonist, exhibits a protective role in the brain. This study investigated whether dexmedetomidine pretreatment attenuates neuroinflammation induced by tibial fracture in rats, as well as the mechanism by which dexmedetomidine provides its neuroprotection. In our study, we observed that tibial fracture significantly increased the levels of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) and the expression of nuclear factor-kappa B (NF-κB) in the hippocampus. Overexpression of microglial (CD11b) and astrocytic (GFAP) responses to injury were observed in the hippocampus. Dexmedetomidine pretreatment significantly suppressed the inflammatory responses, as evidenced by lower TNF-α and IL-1β levels, significantly inhibited NF-κB activity, and alleviated overexpression of microglia and astrocytes in the hippocampus. However, pretreatment with dexmedetomidine failed to attenuate cytokine responses and activity of NF-κB, CD11b and GFAP after vagotomy or treatment with methyllycaconitine, an α-7 nicotinic acetylcholine receptor (α7nAChR) antagonist. These results suggest that pretreatment with dexmedetomidine may attenuate neuroinflammation caused by tibial fracture in rats through vagal-dependent and α7nAChR-dependent mechanisms. PMID:27163720

  19. Pomegranate Polyphenols and Extract Inhibit Nuclear Factor of Activated T-Cell Activity and Microglial Activation In Vitro and in a Transgenic Mouse Model of Alzheimer Disease123

    OpenAIRE

    Rojanathammanee, Lalida; Puig, Kendra L.; Combs, Colin K.

    2013-01-01

    Alzheimer disease (AD) brain is characterized by extracellular plaques of amyloid β (Aβ) peptide with reactive microglia. This study aimed to determine whether a dietary intervention could attenuate microgliosis. Memory was assessed in 12-mo-old male amyloid precursor protein/presenilin 1 (APP/PS1) transgenic mice via Barnes maze testing followed by division into either a control-fed group provided free access to normal chow and water or a treatment group provided free access to normal chow a...

  20. Microarray and pathway analysis reveal distinct mechanisms underlying cannabinoid-mediated modulation of LPS-induced activation of BV-2 microglial cells.

    Directory of Open Access Journals (Sweden)

    Ana Juknat

    Full Text Available Cannabinoids are known to exert immunosuppressive activities. However, the mechanisms which contribute to these effects are unknown. Using lipopolysaccharide (LPS to activate BV-2 microglial cells, we examined how Δ(9-tetrahydrocannabinol (THC, the major psychoactive component of marijuana, and cannabidiol (CBD the non-psychoactive component, modulate the inflammatory response. Microarray analysis of genome-wide mRNA levels was performed using Illumina platform and the resulting expression patterns analyzed using the Ingenuity Pathway Analysis to identify functional subsets of genes, and the Ingenuity System Database to denote the gene networks regulated by CBD and THC. From the 5338 transcripts that were differentially expressed across treatments, 400 transcripts were found to be upregulated by LPS, 502 by CBD+LPS and 424 by THC+LPS, while 145 were downregulated by LPS, 297 by CBD+LPS and 149 by THC+LPS, by 2-fold or more (p≤0.005. Results clearly link the effects of CBD and THC to inflammatory signaling pathways and identify new cannabinoid targets in the MAPK pathway (Dusp1, Dusp8, Dusp2, cell cycle related (Cdkn2b, Gadd45a as well as JAK/STAT regulatory molecules (Socs3, Cish, Stat1. The impact of CBD on LPS-stimulated gene expression was greater than that of THC. We attribute this difference to the fact that CBD highly upregulated several genes encoding negative regulators of both NFκB and AP-1 transcriptional activities, such as Trib3 and Dusp1 known to be modulated through Nrf2 activation. The CBD-specific expression profile reflected changes associated with oxidative stress and glutathione depletion via Trib3 and expression of ATF4 target genes. Furthermore, the CBD affected genes were shown to be controlled by nuclear factors usually involved in regulation of stress response and inflammation, mainly via Nrf2/Hmox1 axis and the Nrf2/ATF4-Trib3 pathway. These observations indicate that CBD, and less so THC, induce a cellular stress

  1. Minocycline treatment inhibits microglial activation and alters spinal levels of endocannabinoids in a rat model of neuropathic pain.

    Science.gov (United States)

    Guasti, Leonardo; Richardson, Denise; Jhaveri, Maulik; Eldeeb, Khalil; Barrett, David; Elphick, Maurice R; Alexander, Stephen P H; Kendall, David; Michael, Gregory J; Chapman, Victoria

    2009-07-01

    Activation of spinal microglia contributes to aberrant pain responses associated with neuropathic pain states. Endocannabinoids (ECs) are present in the spinal cord, and inhibit nociceptive processing; levels of ECs may be altered by microglia which modulate the turnover of endocannabinoids in vitro. Here, we investigate the effect of minocycline, an inhibitor of activated microglia, on levels of the endocannabinoids anandamide and 2-arachidonoylglycerol (2-AG), and the related compound N-palmitoylethanolamine (PEA), in neuropathic spinal cord. Selective spinal nerve ligation (SNL) in rats resulted in mechanical allodynia and the presence of activated microglia in the ipsilateral spinal cord. Chronic daily treatment with minocycline (30 mg/kg, ip for 14 days) significantly reduced the development of mechanical allodynia at days 5, 10 and 14 post-SNL surgery, compared to vehicle-treated SNL rats (P pain states.

  2. Minocycline treatment inhibits microglial activation and alters spinal levels of endocannabinoids in a rat model of neuropathic pain

    Directory of Open Access Journals (Sweden)

    Elphick Maurice R

    2009-07-01

    Full Text Available Abstract Activation of spinal microglia contributes to aberrant pain responses associated with neuropathic pain states. Endocannabinoids (ECs are present in the spinal cord, and inhibit nociceptive processing; levels of ECs may be altered by microglia which modulate the turnover of endocannabinoids in vitro. Here, we investigate the effect of minocycline, an inhibitor of activated microglia, on levels of the endocannabinoids anandamide and 2-arachidonoylglycerol (2-AG, and the related compound N-palmitoylethanolamine (PEA, in neuropathic spinal cord. Selective spinal nerve ligation (SNL in rats resulted in mechanical allodynia and the presence of activated microglia in the ipsilateral spinal cord. Chronic daily treatment with minocycline (30 mg/kg, ip for 14 days significantly reduced the development of mechanical allodynia at days 5, 10 and 14 post-SNL surgery, compared to vehicle-treated SNL rats (P P P P P

  3. Microglia-Secreted Galectin-3 Acts as a Toll-like Receptor 4 Ligand and Contributes to Microglial Activation

    Directory of Open Access Journals (Sweden)

    Miguel Angel Burguillos

    2015-03-01

    Full Text Available Inflammatory response induced by microglia plays a critical role in the demise of neuronal populations in neuroinflammatory diseases. Although the role of toll-like receptor 4 (TLR4 in microglia’s inflammatory response is fully acknowledged, little is known about endogenous ligands that trigger TLR4 activation. Here, we report that galectin-3 (Gal3 released by microglia acts as an endogenous paracrine TLR4 ligand. Gal3-TLR4 interaction was further confirmed in a murine neuroinflammatory model (intranigral lipopolysaccharide [LPS] injection and in human stroke subjects. Depletion of Gal3 exerted neuroprotective and anti-inflammatory effects following global brain ischemia and in the neuroinflammatory LPS model. These results suggest that Gal3-dependent-TLR4 activation could contribute to sustained microglia activation, prolonging the inflammatory response in the brain.

  4. Resolvins AT-D1 and E1 differentially impact functional outcome, post-traumatic sleep, and microglial activation following diffuse brain injury in the mouse.

    Science.gov (United States)

    Harrison, Jordan L; Rowe, Rachel K; Ellis, Timothy W; Yee, Nicole S; O'Hara, Bruce F; Adelson, P David; Lifshitz, Jonathan

    2015-07-01

    Traumatic brain injury (TBI) is induced by mechanical forces which initiate a cascade of secondary injury processes, including inflammation. Therapies which resolve the inflammatory response may promote neural repair without exacerbating the primary injury. Specific derivatives of omega-3 fatty acids loosely grouped as specialized pro-resolving lipid mediators (SPMs) and termed resolvins promote the active resolution of inflammation. In the current study, we investigate the effect of two resolvin molecules, RvE1 and AT-RvD1, on post-traumatic sleep and functional outcome following diffuse TBI through modulation of the inflammatory response. Adult, male C57BL/6 mice were injured using a midline fluid percussion injury (mFPI) model (6-10min righting reflex time for brain-injured mice). Experimental groups included mFPI administered RvE1 (100ng daily), AT-RvD1 (100ng daily), or vehicle (sterile saline) and counterbalanced with uninjured sham mice. Resolvins or saline were administered daily for seven consecutive days beginning 3days prior to TBI to evaluate proof-of-principle to improve outcome. Immediately following diffuse TBI, post-traumatic sleep was recorded for 24h post-injury. For days 1-7 post-injury, motor outcome was assessed by rotarod. Cognitive function was measured at 6days post-injury using novel object recognition (NOR). At 7days post-injury, microglial activation was quantified using immunohistochemistry for Iba-1. In the diffuse brain-injured mouse, AT-RvD1 treatment, but not RvE1, mitigated motor and cognitive deficits. RvE1 treatment significantly increased post-traumatic sleep in brain-injured mice compared to all other groups. RvE1 treated mice displayed a higher proportion of ramified microglia and lower proportion of activated rod microglia in the cortex compared to saline or AT-RvD1 treated brain-injured mice. Thus, RvE1 treatment modulated post-traumatic sleep and the inflammatory response to TBI, albeit independently of improvement in motor

  5. Macrophageal/microglial cell activation and cerebral injury induced by excretory-secretory products secreted by Paragonimus westermani.

    Science.gov (United States)

    Lee, Jae-Chul; Cho, Geum-Sil; Kwon, Jae Hyun; Shin, Myeong Heon; Lim, Ji Hyae; Kim, Won-Ki

    2006-02-01

    Cerebral paragonimiasis causes various neurological disorders including seizures, visual impairment and hemiplegia. The excretory-secretory product (ESP) released by Paragonimus westermani has a cysteine protease activity and plays important roles in its migration in the host tissue and modulation of host immune responses. To gain more insight into the pathogenesis of ESP in the brain, we investigated the inflammatory reaction and cerebral injury following microinjection of ESP into rat striatum. The size of injury was maximally observed 3 days after microinjection of ESP and then declined to control levels as astrocytes have repopulated the injury. ED1-positive monocytes and microglia were confluently found inside the injury. The mRNA expression of inducible nitric oxide synthase (iNOS) occurred as early as 9h after ESP injection and then declined to control levels within 1 day. The iNOS inhibitor aminoguanidine largely decreased the expression of iNOS but did not reduce the size of lesion caused by ESP. Interestingly, however, heat inactivation of ESP caused a decrease of injury formation with no altered expression of iNOS. The data indicate that ESP produces brain tissue injury by recruiting activated monocytes/microglia via heat-labile protease activity.

  6. LPS-induced microglial secretion of TNFα increases activity-dependent neuronal apoptosis in the neonatal cerebral cortex.

    Science.gov (United States)

    Nimmervoll, Birgit; White, Robin; Yang, Jenq-Wei; An, Shuming; Henn, Christopher; Sun, Jyh-Jang; Luhmann, Heiko J

    2013-07-01

    During the pre- and neonatal period, the cerebral cortex reveals distinct patterns of spontaneous synchronized activity, which is critically involved in the formation of early networks and in the regulation of neuronal survival and programmed cell death (apoptosis). During this period, the cortex is also highly vulnerable to inflammation and in humans prenatal infection may have a profound impact on neurodevelopment causing long-term neurological deficits. Using in vitro and in vivo multi-electrode array recordings and quantification of caspase-3 (casp-3)-dependent apoptosis, we demonstrate that lipopolysaccharide-induced inflammation causes rapid alterations in the pattern of spontaneous burst activities, which subsequently leads to an increase in apoptosis. We show that these inflammatory effects are specifically initiated by the microglia-derived pro-inflammatory cytokine tumor necrosis factor α and the chemokine macrophage inflammatory protein 2. Our data demonstrate that inflammation-induced modifications in spontaneous network activities influence casp-3-dependent cell death in the developing cerebral cortex.

  7. Nitrite attenuated peroxynitrite and hypochlorite generation in activated neutrophils.

    Science.gov (United States)

    Ren, Xiaoming; Ding, Yun; Lu, Naihao

    2016-03-15

    Oxidative stress is usually considered as an important factor to the pathogenesis of various diseases. Peroxynitrite (ONOO(-)) and hypochlorite (OCl(-)) are formed in immune cells as a part of the innate host defense system, but excessive reactive oxygen species generation can cause progressive inflammation and tissue damage. It has been proven that through mediating nitric oxide (NO) homeostasis, inorganic nitrite (NO2(-)) shows organ-protective effects on oxidative stress and inflammation. However, the effects of NO2(-) on the function of immune cells were still not clear. The potential role of NO2(-) in modulating ONOO(-) and OCl(-) generation in neutrophil cells was investigated in this study. As an immune cell activator, lipopolysaccharide (LPS) increased both ONOO(-) and OCl(-) production in neutrophils, which was significantly attenuated by NO2(-). NO2(-) reduced superoxide (O2(·-)) generation via a NO-dependent mechanism and increased NO formation in activated neutrophils, suggesting a crucial role of O2(·-) in NO2(-)-mediated reduction of ONOO(-). Moreover, the reduced effect of NO2(-) on OCl(-) production was attributed to that NO2(-) reduced H2O2 production in activated neutrophils without influencing the release of myeloperoxidase (MPO), thus limiting OCl(-) production by MPO/H2O2 system. Therefore, NO2(-) attenuates ONOO(-) and OCl(-) formation in activated neutrophils, opening a new direction to modulate the inflammatory response. PMID:26854590

  8. Herpes simplex virus induces neural oxidative damage via microglial cell Toll-like receptor-2

    Directory of Open Access Journals (Sweden)

    Little Morgan R

    2010-06-01

    Full Text Available Abstract Background Using a murine model of herpes simplex virus (HSV-1 encephalitis, our laboratory has determined that induction of proinflammatory mediators in response to viral infection is largely mediated through a Toll-like receptor-2 (TLR2-dependent mechanism. Published studies have shown that, like other inflammatory mediators, reactive oxygen species (ROS are generated during viral brain infection. It is increasingly clear that ROS are responsible for facilitating secondary tissue damage during central nervous system infection and may contribute to neurotoxicity associated with herpes encephalitis. Methods Purified microglial cell and mixed neural cell cultures were prepared from C57B/6 and TLR2-/- mice. Intracellular ROS production in cultured murine microglia was measured via 2', 7'-Dichlorofluorescin diacetate (DCFH-DA oxidation. An assay for 8-isoprostane, a marker of lipid peroxidation, was utilized to measure free radical-associated cellular damage. Mixed neural cultures obtained from β-actin promoter-luciferase transgenic mice were used to detect neurotoxicity induced by HSV-infected microglia. Results Stimulation with HSV-1 elevated intracellular ROS in wild-type microglial cell cultures, while TLR2-/- microglia displayed delayed and attenuated ROS production following viral infection. HSV-infected TLR2-/- microglia produced less neuronal oxidative damage to mixed neural cell cultures in comparison to HSV-infected wild-type microglia. Further, HSV-infected TLR2-/- microglia were found to be less cytotoxic to cultured neurons compared to HSV-infected wild-type microglia. These effects were associated with decreased activation of p38 MAPK and p42/p44 ERK in TLR2-/- mice. Conclusions These studies demonstrate the importance of microglial cell TLR2 in inducing oxidative stress and neuronal damage in response to viral infection.

  9. Detailed analysis of the promoter activity of an attenuated lentivirus.

    Science.gov (United States)

    Blatti-Cardinaux, Laure; Sanjosé, Leticia; Zahno, Marie-Luise; Zanoni, Reto; Reina, Ramses; Bertoni, Giuseppe

    2016-07-01

    In spite of an eradication campaign that eliminated clinical cases of caprine arthritis encephalitis virus-induced arthritis in the Swiss goat population, seroconversions are still observed. In the affected flocks, viruses belonging mainly to the small ruminant lentivirus A4 subtype are regularly isolated. These viruses are considered attenuated, except in the mammary gland, where high viral loads and histopathological lesions have been observed. We previously characterized and sequenced such field isolates, detecting several potentially attenuating mutations in their LTR. Here we present a detailed analysis of the promoter activity of these genetic elements, which was comparable to those of virulent isolates. An AP-1 binding site was shown to be crucial for promoter activity in reporter gene assays and also in the context of a replicating molecular clone. Other sites, such as AML(vis) and a conserved E-box, appeared to be less crucial. Analysis of a unique AP-4 site showed a clear discrepancy between results obtained with reporter gene assays and those with mutated viruses. Within the limits of this in vitro study, we did not find evidence pointing to the LTR as the genetic correlate of attenuation for these viruses. Finally, the limited replication of SRLV A4 in mammary cell culture could not explain the suggested mammary tropism. In contrast, and in view of the abundance of macrophages in the mammary gland, it is the striking replication capacity of SRLV A4 in these cells, unaffected by all LTR mutations tested, which may explain the apparent mammary tropism of these viruses. PMID:27114068

  10. Curcumin Ameliorates the Reduction Effect of PGE2 on Fibrillar β-Amyloid Peptide (1-42-Induced Microglial Phagocytosis through the Inhibition of EP2-PKA Signaling in N9 Microglial Cells.

    Directory of Open Access Journals (Sweden)

    Gen-Lin He

    Full Text Available Inflammatory activation of microglia and β amyloid (Aβ deposition are considered to work both independently and synergistically to contribute to the increased risk of Alzheimer's disease (AD. Recent studies indicate that long-term use of phenolic compounds provides protection against AD, primarily due to their anti-inflammatory actions. We previously suggested that phenolic compound curcumin ameliorated phagocytosis possibly through its anti-inflammatory effects rather than direct regulation of phagocytic function in electromagnetic field-exposed N9 microglial cells (N9 cells. Here, we explored the prostaglandin-E2 (PGE2-related signaling pathway that involved in curcumin-mediated phagocytosis in fibrillar β-amyloid peptide (1-42 (fAβ42-stimulated N9 cells. Treatment with fAβ42 increased phagocytosis of fluorescent-labeled latex beads in N9 cells. This increase was attenuated in a dose-dependent manner by endogenous and exogenous PGE2, as well as a selective EP2 or protein kinase A (PKA agonist, but not by an EP4 agonist. We also found that an antagonist of EP2, but not EP4, abolished the reduction effect of PGE2 on fAβ42-induced microglial phagocytosis. Additionally, the increased expression of endogenous PGE2, EP2, and cyclic adenosine monophosphate (AMP, and activation of vasodilator-stimulated phosphoprotein, cyclic AMP responsive element-binding protein, and PKA were depressed by curcumin administration. This reduction led to the amelioration of the phagocytic abilities of PGE2-stimulated N9 cells. Taken together, these data suggested that curcumin restored the attenuating effect of PGE2 on fAβ42-induced microglial phagocytosis via a signaling mechanism involving EP2 and PKA. Moreover, due to its immune modulatory effects, curcumin may be a promising pharmacological candidate for neurodegenerative diseases.

  11. Neuroprotection and Functional Recovery Associated with Decreased Microglial Activation Following Selective Activation of mGluR2/3 Receptors in a Rodent Model of Parkinson's Disease

    Directory of Open Access Journals (Sweden)

    Hugh Chan

    2010-01-01

    Full Text Available Clinical trials have demonstrated positive proof of efficacy of dual metabotropic glutamate receptor 2/3 (mGluR2/3 agonists in both anxiety and schizophrenia. Importantly, evidence suggests that these drugs may also be neuroprotective against glutamate excitotoxicity, implicated in the pathogenesis of Parkinson's disease (PD. However, whether this neuroprotection also translates into functional recovery is unclear. In the current study, we examined the neuroprotective efficacy of the dual mGluR2/3 agonist, 2R,4R-4-aminopyrrolidine-2,4-dicarboxylate (2R,4R-APDC, and whether this is accompanied by behavioral recovery in a rodent 6-hydroxydopamine (6-OHDA model of PD. We now report that delayed post lesion treatment with 2R,4R-APDC (10 nmol, results in robust neuroprotection of the nigrostriatal system, which translated into functional recovery as measured by improved forelimb use asymmetry and reduced (+-amphetamine-induced rotation compared to vehicle treated animals. Interestingly, these beneficial effects were associated with a decrease in microglial markers in the SNc, which may suggest an antiinflammatory action of this drug.

  12. Microglial interactions with synapses are modulated by visual experience.

    Directory of Open Access Journals (Sweden)

    Marie-Ève Tremblay

    Full Text Available Microglia are the immune cells of the brain. In the absence of pathological insult, their highly motile processes continually survey the brain parenchyma and transiently contact synaptic elements. Aside from monitoring, their physiological roles at synapses are not known. To gain insight into possible roles of microglia in the modification of synaptic structures, we used immunocytochemical electron microscopy, serial section electron microscopy with three-dimensional reconstructions, and two-photon in vivo imaging to characterize microglial interactions with synapses during normal and altered sensory experience, in the visual cortex of juvenile mice. During normal visual experience, most microglial processes displayed direct apposition with multiple synapse-associated elements, including synaptic clefts. Microglial processes were also distinctively surrounded by pockets of extracellular space. In terms of dynamics, microglial processes localized to the vicinity of small and transiently growing dendritic spines, which were typically lost over 2 d. When experience was manipulated through light deprivation and reexposure, microglial processes changed their morphology, showed altered distributions of extracellular space, displayed phagocytic structures, apposed synaptic clefts more frequently, and enveloped synapse-associated elements more extensively. While light deprivation induced microglia to become less motile and changed their preference of localization to the vicinity of a subset of larger dendritic spines that persistently shrank, light reexposure reversed these behaviors. Taken together, these findings reveal different modalities of microglial interactions with synapses that are subtly altered by sensory experience. These findings suggest that microglia may actively contribute to the experience-dependent modification or elimination of a specific subset of synapses in the healthy brain.

  13. Baroreceptor activation attenuates attentional effects on pain-evoked potentials.

    Science.gov (United States)

    Gray, Marcus A; Minati, Ludovico; Paoletti, Giulia; Critchley, Hugo D

    2010-12-01

    Focused attention typically enhances neural nociceptive responses, reflected electroencephalographically as increased amplitude of pain-evoked event-related potentials (ERPs). Additionally, pain-evoked ERPs are attenuated by hypertension and baroreceptor activity, through as yet unclear mechanisms. There is indirect evidence that these two effects may interact, suggesting that baroreceptor-related modulation of nociception is more than a low-level gating phenomenon. To address this hypothesis, we explored in a group of healthy participants the combined effects of cue-induced expectancy and baroreceptor activity on the amplitude of pain-evoked ERPs. Brief nociceptive skin stimuli were delivered during a simple visual task; half were preceded by a visual forewarning cue, and half were unpredictable. Nociceptive stimuli were timed to coincide either with systole (maximum activation of cardiac baroreceptors) or with diastole (minimum baroreceptor activation). We observed a strong interaction between expectancy and cardiac timing for the amplitude of the P2 ERP component; no effects were observed for the N2 component. Cued stimuli were associated with larger P2 amplitude, but this effect was abolished for stimuli presented during baroreceptor activation. No cardiac timing effect was observed for un-cued stimuli. Taken together, these findings suggest a close integration of cognitive-affective aspects of expectancy and baroreceptor influences on pain, and as such may cast further light on mechanisms underlying mental and physiological contributions to clinical pain.

  14. Isolation and analysis of mouse microglial cells.

    Science.gov (United States)

    Garcia, Jenny A; Cardona, Sandra M; Cardona, Astrid E

    2014-01-01

    Microglia are mononuclear phagocytes that make up about 10% of the central nervous system (CNS). They are known for their surveillant behavior, which involves continuous monitoring of neural tissue by extending and retracting their processes. Microglial cells are derived from myeloid progenitor cells and play important roles in homeostasis as well as inflammatory and immune responses in the brain. This unit describes several microglial cell isolation protocols that can be easily adapted for projects requiring a rapid and efficient analysis of mouse microglial cells by flow cytometry. Methods for visualizing microglial cells using in situ immunohistochemistry and immunochemistry in free-floating sections are also included.

  15. Activation of PERK signaling attenuates Abeta-mediated ER stress.

    Directory of Open Access Journals (Sweden)

    Do Yeon Lee

    Full Text Available Alzheimer's disease (AD is characterized by the deposition of aggregated beta-amyloid (Abeta, which triggers a cellular stress response called the unfolded protein response (UPR. The UPR signaling pathway is a cellular defense system for dealing with the accumulation of misfolded proteins but switches to apoptosis when endoplasmic reticulum (ER stress is prolonged. ER stress is involved in neurodegenerative diseases including AD, but the molecular mechanisms of ER stress-mediated Abeta neurotoxicity still remain unknown. Here, we show that treatment of Abeta triggers the UPR in the SK-N-SH human neuroblastoma cells. Abeta mediated UPR pathway accompanies the activation of protective pathways such as Grp78/Bip and PERK-eIF2alpha pathway, as well as the apoptotic pathways of the UPR such as CHOP and caspase-4. Knockdown of PERK enhances Abeta neurotoxicity through reducing the activation of eIF2alpha and Grp8/Bip in neurons. Salubrinal, an activator of the eIF2alpha pathway, significantly increased the Grp78/Bip ER chaperone resulted in attenuating caspase-4 dependent apoptosis in Abeta treated neurons. These results indicate that PERK-eIF2alpha pathway is a potential target for therapeutic applications in neurodegenerative diseases including AD.

  16. Microglial responses to amyloid β peptide opsonization and indomethacin treatment

    Directory of Open Access Journals (Sweden)

    Leonard Brian

    2005-08-01

    Full Text Available Abstract Background Recent studies have suggested that passive or active immunization with anti-amyloid β peptide (Aβ antibodies may enhance microglial clearance of Aβ deposits from the brain. However, in a human clinical trial, several patients developed secondary inflammatory responses in brain that were sufficient to halt the study. Methods We have used an in vitro culture system to model the responses of microglia, derived from rapid autopsies of Alzheimer's disease patients, to Aβ deposits. Results Opsonization of the deposits with anti-Aβ IgG 6E10 enhanced microglial chemotaxis to and phagocytosis of Aβ, as well as exacerbated microglial secretion of the pro-inflammatory cytokines TNF-α and IL-6. Indomethacin, a common nonsteroidal anti-inflammatory drug (NSAID, had no effect on microglial chemotaxis or phagocytosis, but did significantly inhibit the enhanced production of IL-6 after Aβ opsonization. Conclusion These results are consistent with well known, differential NSAID actions on immune cell functions, and suggest that concurrent NSAID administration might serve as a useful adjunct to Aβ immunization, permitting unfettered clearance of Aβ while dampening secondary, inflammation-related adverse events.

  17. Tissue plasminogen activator attenuates ventilatorinduced lung injury in rats

    Institute of Scientific and Technical Information of China (English)

    Liang-ti HUANG; Hsiu-chu CHOU; Leng-fang WANG; Chung-ming CHEN

    2012-01-01

    Aim:To test the hypothesis that the tissue plasminogen activator (tPA) may counteract the inhibitory effect ot plasminogen activator inhibitors (PAI) and attenuate lung injury in a rat model of ventilator-induced lung injury (VILI).Methods:Adult male Sprague-Dawley rats were ventilated with a HVZP (high-volume zero PEEP) protocol for 2 h at a tidal volume of 30 ml/kg,a respiratory rate of 25 breaths/min,and an inspired oxygen fraction of 21%.The rats were divided into 3 groups (n=7 for each):HVZP+tPA group receiving tPA (1.25 mg/kg,iv) 15 min before ventilation,HVZP group receiving HVZP+vehicle injection,and a control group receiving no ventilation.After 2 h of ventilation,the rats were killed; blood and lungs were collected for biochemical and histological analyses.Results:HVZP ventilation significantly increased total protein content and the concentration of macrophage inflammatory protein-2 (MIP-2) in the bronchoalveolar lavage fluid (BALF) as well as the lung injury score.Rats that received HVZP ventilation had significantly higher lung PAI-1 mRNA expression,plasma PAI-1and plasma D-dimer levels than the control animals,tPA treatment significantly reduced the BALF total protein and the lung injury score as compared to the HVZP group,tPA treatment also significantly decreased the plasma D-dimer levels and the HVZP ventilation-induced lung vascular fibrin thrombi,tPA treatment showed no effect on MIP-2 level in BALF.Conclusion:These results demonstrate that VILI increases lung PAI-1 mRNA expression,plasma levels of PAI-1 and D-limers,lung injury score and vascular fibrin deposition,tPA can attenuate VILI by decreasing capillary-alveolar protein leakage as well as local and systemic coagulation as shown by decreased lung vascular fibrin deposition and plasma D-dimers.

  18. Microglial interleukin-1β in the ipsilateral dorsal horn inhibits the development of mirror-image contralateral mechanical allodynia through astrocyte activation in a rat model of inflammatory pain.

    Science.gov (United States)

    Choi, Hoon-Seong; Roh, Dae-Hyun; Yoon, Seo-Yeon; Moon, Ji-Young; Choi, Sheu-Ran; Kwon, Soon-Gu; Kang, Suk-Yun; Han, Ho-Jae; Kim, Hyun-Woo; Beitz, Alvin J; Oh, Seog-Bae; Lee, Jang-Hern

    2015-06-01

    Damage on one side of the body can also result in pain on the contralateral unaffected side, called mirror-image pain (MIP). Currently, the mechanisms responsible for the development of MIP are unknown. In this study, we investigated the involvement of spinal microglia and interleukin-1β (IL-1β) in the development of MIP using a peripheral inflammatory pain model. After unilateral carrageenan injection, mechanical allodynia (MA) in both hind paws and the expression levels of spinal Iba-1, IL-1β, and GFAP were evaluated. Ipsilateral MA was induced beginning at 3 hours after carrageenan injection, whereas contralateral MA showed a delayed onset occurring 5 days after injection. A single intrathecal (i.t.) injection of minocycline, a tetracycline derivative that displays selective inhibition of microglial activation, or an interleukin-1 receptor antagonist (IL-1ra) on the day of carrageenan injection caused an early temporary induction of contralateral MA, whereas repeated i.t. treatment with these drugs from days 0 to 3 resulted in a long-lasting contralateral MA, which was evident in its advanced development. We further showed that IL-1β was localized to microglia and that minocycline inhibited the carrageenan-induced increases in spinal Iba-1 and IL-1β expression. Conversely, minocycline or IL-1ra pretreatment increased GFAP expression as compared with that of control rats. However, i.t. pretreatment with fluorocitrate, an astrocyte inhibitor, restored minocycline- or IL-1ra-induced contralateral MA. These results suggest that spinal IL-1β derived from activated microglia temporarily suppresses astrocyte activation, which can ultimately prevent the development of contralateral MA under inflammatory conditions. These findings imply that microglial IL-1β plays an important role in regulating the induction of inflammatory MIP. PMID:25749305

  19. Systemic inflammation regulates microglial responses to tissue damage in vivo

    OpenAIRE

    Gyoneva, Stefka; Davalos, Dimitrios; Biswas, Dipankar; Swanger, Sharon A.; Garnier-Amblard, Ethel; Loth, Francis; Akassoglou, Katerina; Traynelis, Stephen F

    2014-01-01

    Microglia, the resident immune cells of the central nervous system, exist in either a “resting” state associated with physiological tissue surveillance or an “activated” state in neuroinflammation. We recently showed that ATP is the primary chemoattractor to tissue damage in vivo and elicits opposite effects on the motility of activated microglia in vitro through activation of adenosine A2A receptors. However, whether systemic inflammation affects microglial responses to tissue damage in vivo...

  20. Stress Granules Modulate SYK to Cause Microglial Cell Dysfunction in Alzheimer's Disease

    Directory of Open Access Journals (Sweden)

    Soumitra Ghosh

    2015-11-01

    Full Text Available Microglial cells in the brains of Alzheimer's patients are known to be recruited to amyloid-beta (Aβ plaques where they exhibit an activated phenotype, but are defective for plaque removal by phagocytosis. In this study, we show that microglia stressed by exposure to sodium arsenite or Aβ(1–42 peptides or fibrils form extensive stress granules (SGs to which the tyrosine kinase, SYK, is recruited. SYK enhances the formation of SGs, is active within the resulting SGs and stimulates the production of reactive oxygen and nitrogen species that are toxic to neuronal cells. This sequestration of SYK inhibits the ability of microglial cells to phagocytose Escherichia coli or Aβ fibrils. We find that aged microglial cells are more susceptible to the formation of SGs; and SGs containing SYK and phosphotyrosine are prevalent in the brains of patients with severe Alzheimer's disease. Phagocytic activity can be restored to stressed microglial cells by treatment with IgG, suggesting a mechanism to explain the therapeutic efficacy of intravenous IgG. These studies describe a mechanism by which stress, including exposure to Aβ, compromises the function of microglial cells in Alzheimer's disease and suggest approaches to restore activity to dysfunctional microglial cells.

  1. Deciphering resting microglial morphology and process motility from a synaptic prospect

    Directory of Open Access Journals (Sweden)

    Ines eHristovska

    2016-01-01

    Full Text Available Microglia, the resident immune cells of the central nervous system (CNS, were traditionally believed to be set into action only in case of injury or disease. Accordingly, microglia were assumed to be inactive or resting in the healthy brain. However, recent studies revealed that microglia carry out active tissue sampling in the intact brain by extending and retracting their ramified processes while periodically contacting synapses. Microglial morphology and motility as well as the frequency and duration of physical contacts with synaptic elements were found to be modulated by neuronal activity, sensory experience and neurotransmission; however findings have not been straightforward. Microglial cells are the most morphologically plastic element of the CNS. This unique feature confers them the possibility to locally sense activity, and to respond adequately by establishing synaptic contacts to regulate synaptic inputs by the secretion of signaling molecules. Indeed, microglial cells can hold new roles as critical players in maintaining brain homeostasis and regulating synaptic number, maturation and plasticity. For this reason, a better characterization of microglial cells and cues mediating neuron-to-microglia communication under physiological conditions may help advance our understanding of the microglial behavior and its regulation in the healthy brain. This review highlights recent findings on the instructive role of neuronal activity on microglial motility and microglia-synapse interactions, focusing on the main transmitters involved in this communication and including newly described communication at the tripartite synapse.

  2. Microglial and macrophage reactions mark progressive changes and define the penumbra in the rat neocortex and striatum after transient middle cerebral artery occlusion

    DEFF Research Database (Denmark)

    Lehrmann, E; Christensen, Thomas; Zimmer, J;

    1997-01-01

    significant differences in the characteristics and timing of the microglial/macrophage responses between the caudate putamen and neocortical infarct zones, the infarct zones and their associated penumbral zones, as well as between the striatal and the neocortical penumbral zone. Infiltrations....../macrophages in the adjacent penumbra. Within the neocortex, a later onset of degeneration along the insular-parietal axis was marked by neuronal expression of heat shock protein and a progressive microglial activation with induction of the full repertoire of microglial activation markers, including a widespread microglial...

  3. Active acoustic leak detection for LMFBR steam generator. Sound attenuation due to bubbles

    Energy Technology Data Exchange (ETDEWEB)

    Kumagai, Hiromichi; Sakuma, Toshio [Central Research Inst. of Electric Power Industry, Komae, Tokyo (Japan). Komae Research Lab.

    1995-06-01

    In the steam generators (SG) of LMFBR, it is necessary to detect the leakage of water from tubes of heat exchangers as soon as it occurs. The active acoustic detection method has drawn general interest owing to its short response time and reduction of the influence of background noise. In this paper, the application of the active acoustic detection method for SG is proposed, and sound attenuation by bubbles is investigated experimentally. Furthermore, using the SG sector model, sound field characteristics and sound attenuation characteristics due to injection of bubbles are studied. It is clarified that the sound attenuation depends upon bubble size as well as void fraction, that the distance attenuation of sound in the SG model containing heat transfer tubes is 6dB for each two-fold increase of distance, and that emitted sound attenuates immediately upon injection of bubbles. (author).

  4. Low-level laser therapy regulates microglial function through Src-mediated signaling pathways: implications for neurodegenerative diseases

    OpenAIRE

    Song Sheng; Zhou Feifan; Chen Wei R

    2012-01-01

    Abstract Background Activated microglial cells are an important pathological component in brains of patients with neurodegenerative diseases. The purpose of this study was to investigate the effect of He-Ne (632.8 nm, 64.6 mW/cm2) low-level laser therapy (LLLT), a non-damaging physical therapy, on activated microglia, and the subsequent signaling events of LLLT-induced neuroprotective effects and phagocytic responses. Methods To model microglial activation, we treated the microglial BV2 cells...

  5. Inhomogeneous distribution of Iba-1 characterizes microglial pathology in Alzheimer's disease.

    Science.gov (United States)

    Tischer, Jasmin; Krueger, Martin; Mueller, Wolf; Staszewski, Ori; Prinz, Marco; Streit, Wolfgang J; Bechmann, Ingo

    2016-09-01

    Microglial dystrophy has recently been described as a morphological phenotype of microglia that differs from resting and activated states by spheroid formation and cytorrhexis. In thick sections immunolabeled for HLA-DR or Iba-1 dystrophic microglial processes lose their typical, homogeneous staining pattern and appear to be fragmented or clustered. In this study, we performed double immunofluorescence and electron microscopy to determine if this labeling pattern indeed reflects complete separation of microglial processes from the soma. Using Iba-1/CD68 and Iba-1/MHC class II, as microglial markers, we observed that isolated Iba-1 fragments were still connected to each other by segments of the microglial process immune positive for CD68 or MHC class II. Ultrathin serial sections of two Iba-1 fragments which appeared to be disconnected from each other at the light microscopical level revealed a still existing "bridge" with a diameter of around 0.182 µm. Therefore, microglial dystrophy may reflect alterations of the cytoskeleton ultimately leading to slow cytorrhexis. GLIA 2016;64:1562-1572. PMID:27404378

  6. Regulation of microglia activity by glaucocalyxin-A: attenuation of lipopolysaccharide-stimulated neuroinflammation through NF-κB and p38 MAPK signaling pathways.

    Directory of Open Access Journals (Sweden)

    Byung-Wook Kim

    Full Text Available Microglial cells are the resident macrophages and intrinsic arm of the central nervous system innate immune defense. Microglial cells become activated in response to injury, infection, environmental toxins, and other stimuli that threaten neuronal survival. Therefore, regulating microglial activation may have therapeutic benefits that lead to alleviating the progression of inflammatory-mediated neurodegeneration. In the present study, we investigated the effect of glaucocalyxin A (GLA isolated from Rabdosia japonica on the production of pro-inflammatory mediators in lipopolysaccharide (LPS-stimulated primary microglia and BV-2 cells. GLA significantly inhibited LPS-induced production of nitric oxide and reversed the morphological changes in primary microglia. Further, GLA suppressed expression of inducible nitric oxide synthase and cyclooxygenase-2 dose-dependently at the mRNA and protein levels. The production of proinflammatory cytokines such as tumor necrosis factor-α, interleukin-1β (IL-1β, and IL-6 were inhibited by suppressing their transcriptional activity. Furthermore, GLA suppressed nuclear factor-κB activation by blocking degradation of IκB-α and inhibited the induction of lipocalin-2 expression in LPS-stimulated BV-2 cells. Mechanistic study revealed that the inhibitory effects of GLA were accompanied by blocking the p38 mitogen activated protein kinase signaling pathway in activated microglia. In conclusion, given that microglial activation contributes to the pathogenesis of neurodegenerative diseases, GLA could be developed as a potential therapeutic agent for treating microglia-mediated neuroinflammatory diseases.

  7. Microglial involvement in neuroplastic changes following focal brain ischemia in rats.

    Directory of Open Access Journals (Sweden)

    Alexandre Madinier

    Full Text Available The pathogenesis of ischemic stroke is a complex sequence of events including inflammatory reaction, for which the microglia appears to be a major cellular contributor. However, whether post-ischemic activation of microglial cells has beneficial or detrimental effects remains to be elucidated, in particular on long term brain plasticity events. The objective of our study was to determine, through modulation of post-stroke inflammatory response, to what extent microglial cells are involved in some specific events of neuronal plasticity, neurite outgrowth and synaptogenesis. Since microglia is a source of neurotrophic factors, the identification of the brain-derived neurophic factor (BDNF as possible molecular actor involved in these events was also attempted. As a means of down-regulating the microglial response induced by ischemia, 3-aminobenzamide (3-AB, 90 mg/kg, i.p. was used to inhibit the poly(ADP-ribose polymerase-1 (PARP-1. Indeed, PARP-1 contributes to the activation of the transcription factor NF-kB, which is essential to the upregulation of proinflammatory genes, in particular responsible for microglial activation/proliferation. Experiments were conducted in rats subjected to photothrombotic ischemia which leads to a strong and early microglial cells activation/proliferation followed by an infiltration of macrophages within the cortical lesion, events evaluated at serial time points up to 1 month post-ictus by immunostaining for OX-42 and ED-1. Our most striking finding was that the decrease in acute microglial activation induced by 3-AB was associated with a long term down-regulation of two neuronal plasticity proteins expression, synaptophysin (marker of synaptogenesis and GAP-43 (marker of neuritogenesis as well as to a significant decrease in tissue BDNF production. Thus, our data argue in favour of a supportive role for microglia in brain neuroplasticity stimulation possibly through BDNF production, suggesting that a targeted

  8. Microglial inflammation in the parkinsonian substantia nigra: relationship to alpha-synuclein deposition

    Directory of Open Access Journals (Sweden)

    Pearce Ronald KB

    2005-06-01

    Full Text Available Abstract Background The role of both microglial activation and alpha-synuclein deposition in Parkinson's disease remain unclear. We have tested the hypothesis that if microglia play a primary role in Parkinson's disease pathogenesis, the microglial "activated" phenotype should be associated with histopathological and/or clinical features of the disease. Methods We have examined microglial MHC class II expression, a widely used marker of microglial activation, the occurrence of CD68-positive phagocytes and alpha-synuclein immunoreactivity in post-mortem human substantia nigra affected by idiopathic Parkinson's disease (PD. Using semi-quantitative severity ratings, we have examined the relationship between microglial activation, alpha-synuclein deposition, classical neuropathological criteria for PD, subtype of the disease and clinical course. Results While we did not observe an association between microglial MHC class II expression and clinical parameters, we did find a correlation between disease duration and the macrophage marker CD68 which is expressed by phagocytic microglia. In addition, we observed a significant correlation between the degree of MHC class II expression and alpha-synuclein deposition in the substantia nigra in PD. Conclusion While microglia appeared to respond to alpha-synuclein deposition, MHC class II antigen expression by microglia in the substantia nigra cannot be used as an indicator of clinical PD severity or disease progression. In addition, a contributory or even causative role for microglia in the neuronal loss associated with PD as suggested by some authors seems unlikely. Our data further suggest that an assessment of microglial activation in the aged brain on the basis of immunohistochemistry for MHC class II antigens alone should be done with caution.

  9. Effects of Paeonol on Anti-Neuroinflammatory Responses in Microglial Cells

    Directory of Open Access Journals (Sweden)

    Chingju Lin

    2015-04-01

    Full Text Available Increasing studies suggest that inflammatory processes in the central nervous system mediated by microglial activation plays an important role in numerous neurodegenerative diseases. Development of planning for microglial suppression is considered a key strategy in the search for neuroprotection. Paeonol is a major phenolic component of Moutan Cortex, widely used as a nutrient supplement in Chinese medicine. In this study, we investigated the effects of paeonol on microglial cells stimulated by inflammagens. Paeonol significantly inhibited the release of nitric oxide (NO and the expressions of inducible nitric oxide synthase (iNOS and cyclooxygenase-2 (COX-2. Treatment with paeonol also reduced reactive oxygen species (ROS production and inhibited an ATP-induced increased cell migratory activity. Furthermore, the inhibitory effects of neuroinflammation by paeonol were found to be regulated by phosphorylated adenosine monophosphate-activated protein kinase-α (AMPK-α and glycogen synthase kinase 3 α/β (GSK 3α/β. Treatment with AMPK or GSK3 inhibitors reverse the inhibitory effect of neuroinflammation by paeonol in microglial cells. Furthermore, paeonol treatment also showed significant improvement in the rotarod performance and microglial activation in the mouse model as well. The present study is the first to report a novel inhibitory role of paeonol on neuroinflammation, and presents a new candidate agent for the development of therapies for inflammation-related neurodegenerative diseases.

  10. Ethanol downregulates N-acyl phosphatidylethanolamine-phospholipase D expression in BV2 microglial cells via epigenetic mechanisms.

    Science.gov (United States)

    Correa, Fernando; De Laurentiis, Andrea; Franchi, Ana María

    2016-09-01

    Excessive ethanol drinking has deleterious effects on the brain. However, the effects of alcohol on microglia, the main mediator of the brain's innate immune response remain poorly understood. On the other hand, the endocannabinoid system plays a fundamental role in regulating microglial reactivity and function. Here we studied the effects of acute ethanol exposure to murine BV2 microglial cells on N-acyl phosphatidylethanolamine-phospholipase D (NAPE-PLD), a major synthesizing enzyme of anandamide and other N-acylethanolamines. We found that ethanol downregulated microglial NAPE-PLD expression by activating cAMP/PKA and ERK1/2. These signaling pathways converged on increased phosphorylation of CREB. Moreover, ethanol induced and increase in histone acetyltransferase activity which led to higher levels of acetylation of histone H3. Taken together, our results suggest that ethanol actions on microglial NAPE-PLD expression might involve epigenetic mechanisms. PMID:27266665

  11. Macrophage colony-stimulating factor and its receptor signaling augment glycated albumin-induced retinal microglial inflammation in vitro

    Directory of Open Access Journals (Sweden)

    Jiang Chun H

    2011-01-01

    Full Text Available Abstract Background Microglial activation and the proinflammatory response are controlled by a complex regulatory network. Among the various candidates, macrophage colony-stimulating factor (M-CSF is considered an important cytokine. The up-regulation of M-CSF and its receptor CSF-1R has been reported in brain disease, as well as in diabetic complications; however, the mechanism is unclear. An elevated level of glycated albumin (GA is a characteristic of diabetes; thus, it may be involved in monocyte/macrophage-associated diabetic complications. Results The basal level of expression of M-CSF/CSF-1R was examined in retinal microglial cells in vitro. Immunofluorescence, real-time PCR, immunoprecipitation, and Western blot analyses revealed the up-regulation of CSF-1R in GA-treated microglial cells. We also detected increased expression and release of M-CSF, suggesting that the cytokine is produced by activated microglia via autocrine signaling. Using an enzyme-linked immunosorbent assay, we found that GA affects microglial activation by stimulating the release of tumor necrosis factor-α and interleukin-1β. Furthermore, the neutralization of M-CSF or CSF-1R with antibodies suppressed the proinflammatory response. Conversely, this proinflammatory response was augmented by the administration of M-CSF. Conclusions We conclude that GA induces microglial activation via the release of proinflammatory cytokines, which may contribute to the inflammatory pathogenesis of diabetic retinopathy. The increased microglial expression of M-CSF/CSF-1R not only is a response to microglial activation in diabetic retinopathy but also augments the microglial inflammation responsible for the diabetic microenvironment.

  12. Enhanced microglial clearance of myelin debris in T cell-infiltrated central nervous system

    DEFF Research Database (Denmark)

    Nielsen, Helle Hvilsted; Ladeby, Rune; Fenger, Christina;

    2009-01-01

    system. We investigated T-cell infiltration, myelin clearance, microglial activation, and phagocytic activity distal to sites of axonal transection through analysis of the perforant pathway deafferented dentate gyrus in SJL mice that had received T cells specific for myelin basic protein (TMBP......Acute multiple sclerosis lesions are characterized by accumulation of T cells and macrophages, destruction of myelin and oligodendrocytes, and axonal damage. There is, however, limited information on neuroimmune interactions distal to sites of axonal damage in the T cell-infiltrated central nervous...... with TMBP but not TOVA enhanced the microglial response to axonal transection and microglial phagocytosis of myelin debris associated with the degenerating axons. Because myelin antigen-specific immune responses may provoke protective immunity, increased phagocytosis of myelin debris might enhance...

  13. Activation of TRPV1 reduces vascular lipid accumulation and attenuates atherosclerosis

    DEFF Research Database (Denmark)

    Ma, Liqun; Zhong, Jian; Zhao, Zhigang;

    2011-01-01

    Activation of transient receptor potential vanilloid type-1 (TRPV1) channels may affect lipid storage and the cellular inflammatory response. Now, we tested the hypothesis that activation of TRPV1 channels attenuates atherosclerosis in apolipoprotein E knockout mice (ApoE(-/-)) but not Apo...

  14. Microglial dysfunction connects depression and Alzheimer's disease.

    Science.gov (United States)

    Santos, Luís Eduardo; Beckman, Danielle; Ferreira, Sergio T

    2016-07-01

    Alzheimer's disease (AD) and major depressive disorder (MDD) are highly prevalent neuropsychiatric conditions with intriguing epidemiological overlaps. Depressed patients are at increased risk of developing late-onset AD, and around one in four AD patients are co-diagnosed with MDD. Microglia are the main cellular effectors of innate immunity in the brain, and their activation is central to neuroinflammation - a ubiquitous process in brain pathology, thought to be a causal factor of both AD and MDD. Microglia serve several physiological functions, including roles in synaptic plasticity and neurogenesis, which may be disrupted in neuroinflammation. Following early work on the 'sickness behavior' of humans and other animals, microglia-derived inflammatory cytokines have been shown to produce depressive-like symptoms when administered exogenously or released in response to infection. MDD patients consistently show increased circulating levels of pro-inflammatory cytokines, and anti-inflammatory drugs show promise for treating depression. Activated microglia are abundant in the AD brain, and concentrate around senile plaques, hallmark lesions composed of aggregated amyloid-β peptide (Aβ). The Aβ burden in affected brains is regulated largely by microglial clearance, and the complex activation state of microglia may be crucial for AD progression. Intriguingly, recent reports have linked soluble Aβ oligomers, toxins that accumulate in AD brains and are thought to cause memory impairment, to increased brain cytokine production and depressive-like behavior in mice. Here, we review recent findings supporting the inflammatory hypotheses of AD and MDD, focusing on microglia as a common player and therapeutic target linking these devastating disorders. PMID:26612494

  15. Blockade of microglial KATP -channel abrogates suppression of inflammatory-mediated inhibition of neural precursor cells.

    Science.gov (United States)

    Ortega, Francisco J; Vukovic, Jana; Rodríguez, Manuel J; Bartlett, Perry F

    2014-02-01

    Microglia positively affect neural progenitor cell physiology through the release of inflammatory mediators or trophic factors. We demonstrated previously that reactive microglia foster K(ATP) -channel expression and that blocking this channel using glibenclamide administration enhances striatal neurogenesis after stroke. In this study, we investigated whether the microglial K(ATP) -channel directly influences the activation of neural precursor cells (NPCs) from the subventricular zone using transgenic Csf1r-GFP mice. In vitro exposure of NPCs to lipopolysaccharide and interferon-gamma resulted in a significant decrease in precursor cell number. The complete removal of microglia from the culture or exposure to enriched microglia culture also decreased the precursor cell number. The addition of glibenclamide rescued the negative effects of enriched microglia on neurosphere formation and promoted a ∼20% improvement in precursor cell number. Similar results were found using microglial-conditioned media from isolated microglia. Using primary mixed glial and pure microglial cultures, glibenclamide specifically targeted reactive microglia to restore neurogenesis and increased the microglial production of the chemokine monocyte chemoattractant protein-1 (MCP-1). These findings provide the first direct evidence that the microglial K(ATP) -channel is a regulator of the proliferation of NPCs under inflammatory conditions.

  16. Microglial Hv1 proton channel promotes cuprizone-induced demyelination through oxidative damage.

    Science.gov (United States)

    Liu, Junli; Tian, Daishi; Murugan, Madhuvika; Eyo, Ukpong B; Dreyfus, Cheryl F; Wang, Wei; Wu, Long-Jun

    2015-10-01

    NADPH oxidase (NOX)-dependent reactive oxygen species (ROS) production in inflammatory cells including microglia plays an important role in demyelination and free radical-mediated tissue injury in multiple sclerosis (MS). However, the mechanism underlying microglial ROS production and demyelination remains largely unknown. The voltage-gated proton channel, Hv1, is selectively expressed in microglia and is required for NOX-dependent ROS generation in the brain. In the present study, we sought to determine the role of microglial Hv1 proton channels in a mouse model of cuprizone-induced demyelination, a model for MS. Following cuprizone exposure, wild-type mice presented obvious demyelination, decreased myelin basic protein expression, loss of mature oligodendrocytes, and impaired motor coordination in comparison to mice on a normal chow diet. However, mice lacking Hv1 (Hv1(-/-) ) are partially protected from demyelination and motor deficits compared with those in wild-type mice. These rescued phenotypes in Hv1(-/-) mice in cuprizone-induced demyelination is accompanied by reduced ROS production, ameliorated microglial activation, increased oligodendrocyte progenitor cell (NG2) proliferation, and increased number of mature oligodendrocytes. These results demonstrate that the Hv1 proton channel is required for cuprizone-induced microglial oxidative damage and subsequent demyelination. Our study suggests that the microglial Hv1 proton channel is a unique target for controlling NOX-dependent ROS production in the pathogenesis of MS.

  17. Effect of GSM-1800 and U.M.T.S. exposures on micro-glial activation and heat shock proteins induction in brain: a study on young adult and elderly rats

    Energy Technology Data Exchange (ETDEWEB)

    Laclau, M.; Billaudel, B.; Taxil, M.; Haro, E.; Ruffie, G.; Sanchez, S.; Poulletier De Gannes, F.; Lagroye, I.; Veyret, B. [PIOM/Bioelecromagnetics Lab., ENSCPB/EPHE, 33 - Pessac (France)

    2006-07-01

    Contradictory results have emerged from recent studies describing low -level radiofrequency radiation (R.F.R.) as a hazardous factor for the central nervous system while others described such type of exposure as totally safe. In the brain, heat shock proteins (H.s.p.) are often induced under harmful conditions such as ischemia, traumatic injury, epilepsy, hyperthermia, drug administration, and neuro-degenerative diseases. Under those conditions, activation of the micro-glial cell population is often observed. In this work we studied the effect of two types of mobile phone signals, GSM-1800 and U.M.T.S. on the expression of two major H.s.p., induced in the brain under harmful conditions, H.s.p. 70 and H.s.p. 25. We also studied micro-glial activation in young adult (8 weeks) and elderly (17 months) Wistar rats. Height animals by group were exposed. Exposures were performed using a brain-averaged S.A.R. of 2 W/kg following two types of protocols: an acute exposure, with exposure lasting only two hours, and a sub chronic exposure in which the animals were exposed for two hours per day, five days per week, during four weeks. In all cases, rats were progressively habituated to the exposure setup (rockets) over two weeks to avoid stress and a sham group was exposed for each condition. Positive controls were performed by induction of a status epilepticus using a subcutaneous injection kainic acid (10 mg/kg). At the end of exposure, rats were anesthetized with isofluran and perfused from the heart with P.B.S. then paraformaldehyde prior to removing of the brain. Sections (10 m m thick) were prepared on slides for immunohistochemistry. Brain samples were coded and the analysis was performed in a blind manner. The sections were immuno-histo-chemically stained with antibodies raised in rabbits against H.s.p.25 and against the inducible form of H.s.p.70. The whole glial cell population was detected by its common cell surface glyco conjugates, which bind the plant Griffonia

  18. State space approach for joint estimation of activity and attenuation map from PET emission sinograms

    Institute of Scientific and Technical Information of China (English)

    Liu Huafeng; You Hongshun; Shi Pengcheng

    2007-01-01

    Quantitative estimation of radioactivity map has important clinical implications for better diagnosis and understanding of cancers. Although attenuation map and activity map are usually treated sequentially, they can obviously benefit a great deal when the transmission data is missing. In this paper, we propose a novel scheme of simultaneously solving for attenuation map and activity distribution from emission sinograms. Our strategy combines the measurement model of PET, and the attenuation parameters are treated as random variables with known prior statistics. After the conversion to state space representation, the extended Kalman filtering procedures are adopted to linearize the equations and to provide the joint estimates in an approximate optimal sense. Experiments have been performed on both synthetic data to illustrate its abilities and benefits.

  19. TMEM16F Regulates Spinal Microglial Function in Neuropathic Pain States

    Directory of Open Access Journals (Sweden)

    Laura Batti

    2016-06-01

    Full Text Available Neuropathic pain is a widespread chronic pain state that results from injury to the nervous system. Spinal microglia play a causative role in the pathogenesis of neuropathic pain through secretion of growth factors and cytokines. Here, we investigated the contribution of TMEM16F, a protein that functions as a Ca2+-dependent ion channel and a phospholipid scramblase, to microglial activity during neuropathic pain. We demonstrate that mice with a conditional ablation of TMEM16F in microglia do not develop mechanical hypersensitivity upon nerve injury. In the absence of TMEM16F, microglia display deficits in process motility and phagocytosis. Moreover, loss of GABA immunoreactivity upon injury is spared in TMEM16F conditional knockout mice. Collectively, these data indicate that TMEM16F is an essential component of the microglial response to injury and suggest the importance of microglial phagocytosis in the pathogenesis of neuropathic pain.

  20. Curcumin attenuates diet-induced hepatic steatosis by activating AMP-activated protein kinase.

    Science.gov (United States)

    Um, Min Young; Hwang, Kwang Hyun; Ahn, Jiyun; Ha, Tae Youl

    2013-09-01

    Curcumin is a well-known component of traditional turmeric (Curcuma longa), which has been reported to prevent obesity and diabetes. However, the effect of curcumin on hepatic lipid metabolism remains unclear. The aim of this study was to examine the effects of curcumin on hepatic steatosis in high-fat/cholesterol diet (HFD)-induced obese mice. Male C57BL/6J mice were fed a normal diet (ND), HFD or HFD with 0.15% curcumin (HFD+C) for 11 weeks. We found that curcumin significantly lowered the body-weight and adipose tissue weight of mice in the HFD+C group compared with the findings for the HFD group (p cholesterol, fasting glucose and insulin in serum were decreased, and HFD-induced impairment of insulin sensitivity was improved by curcumin supplementation (p Curcumin protected against the development of hepatic steatosis by reducing hepatic fat accumulation. Moreover, curcumin activated AMP-activated protein kinase (AMPK) and elevated the gene expression of peroxisome proliferator-activated receptor alpha. By contrast, curcumin suppressed the HFD-mediated increases in sterol regulatory element-binding protein-1, acetyl-CoA carboxylase 1, fatty acid synthase and cluster of differentiation 36 expression. Taken together, these findings indicate that curcumin attenuates HFD-induced hepatic steatosis by regulating hepatic lipid metabolism via AMPK activation, suggesting its use as a therapeutic for hepatic steatosis.

  1. Physical Activity Attenuates the Influence of FTO Variants on Obesity Risk

    DEFF Research Database (Denmark)

    Oskari Kilpeläinen, Tuomas; Qi, Lu; Brage, Soren;

    2011-01-01

    .20–1.26), but PA attenuated this effect (pinteraction = 0.001). More specifically, the minor allele of rs9939609 increased the odds of obesity less in the physically active group (odds ratio = 1.22/allele, 95% CI 1.19–1.25) than in the inactive group (odds ratio = 1.30/allele, 95% CI 1...

  2. Voluntary activation of the sympathetic nervous system and attenuation of the innate immune response in humans

    NARCIS (Netherlands)

    Kox, M.; Eijk, L.T.G.J. van; Zwaag, J.; Wildenberg, J. van den; Sweep, F.C.; Hoeven, J.G. van der; Pickkers, P.

    2014-01-01

    Excessive or persistent proinflammatory cytokine production plays a central role in autoimmune diseases. Acute activation of the sympathetic nervous system attenuates the innate immune response. However, both the autonomic nervous system and innate immune system are regarded as systems that cannot b

  3. Activation of AMP-activated protein kinase attenuates hepatocellular carcinoma cell adhesion stimulated by adipokine resistin

    International Nuclear Information System (INIS)

    Resistin, adipocyte-secreting adipokine, may play critical role in modulating cancer pathogenesis. The aim of this study was to investigate the effects of resistin on HCC adhesion to the endothelium, and the mechanism underlying these resistin effects. Human SK-Hep1 cells were used to study the effect of resistin on intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expressions as well as NF-κB activation, and hence cell adhesion to human umbilical vein endothelial cells (HUVECs). 5-Aminoimidazole-4-carboxamide 1-β-D-ribofuranoside (AICAR), an AMP-activated protein kinase (AMPK) activator, was used to determine the regulatory role of AMPK on HCC adhesion to the endothelium in regard to the resistin effects. Treatment with resistin increased the adhesion of SK-Hep1 cells to HUVECs and concomitantly induced NF-κB activation, as well as ICAM-1 and VCAM-1 expressions in SK-Hep1 cells. Using specific blocking antibodies and siRNAs, we found that resistin-induced SK-Hep1 cell adhesion to HUVECs was through NF-κB-regulated ICAM-1 and VCAM-1 expressions. Moreover, treatment with AICAR demonstrated that AMPK activation in SK-Hep1 cells significantly attenuates the resistin effect on SK-Hep1 cell adhesion to HUVECs. These results clarify the role of resistin in inducing HCC adhesion to the endothelium and demonstrate the inhibitory effect of AMPK activation under the resistin stimulation. Our findings provide a notion that resistin play an important role to promote HCC metastasis and implicate AMPK may be a therapeutic target to against HCC metastasis

  4. Metformin attenuates pressure overload-induced cardiac hypertrophy via AMPK activation

    Institute of Scientific and Technical Information of China (English)

    Yong-nan FU; Han XIAO; Xiao-wei MA; Sheng-yang JIANG; Ming XU; You-yi ZHANG

    2011-01-01

    Aim: To identify the role of metformin in cardiac hypertrophy and investigate the possible mechanism underlying this effect.Methods: Wild type and AMPKα2 knockout (AMPKα2-/-) littermates were subjected to left ventricular pressure overload caused by evaluated using echocardiography and anatomic and histological methods. The antihypertrophic mechanism of metformin was analyzed using Western blotting.Results: Metformin significantly attenuated cardiac hypertrophy induced by pressure overload in wild type mice, but the antihypertrophic actions of metformin were ablated in AMPKx2-/- mice. Furthermore, metformin suppressed the phosphorylation of Akt/protein kinase B (AKT) and mammalian target of rapamycin (mTOR) in response to pressure overload in wild type mice, but not in AMPKα2-/-mice.Conclusion: Long-term administration of metformin may attenuate cardiac hypertrophy induced by pressure overload in nondiabetic mice, and this attenuation is highly dependent on AMPK activation. These findings may provide a potential therapy for patients at risk of developing pathological cardiac hypertrophy.

  5. Inhibition of NF-κB activity in the hypothalamic paraventricular nucleus attenuates hypertension and cardiac hypertrophy by modulating cytokines and attenuating oxidative stress

    International Nuclear Information System (INIS)

    We hypothesized that chronic inhibition of NF-κB activity in the hypothalamic paraventricular nucleus (PVN) delays the progression of hypertension and attenuates cardiac hypertrophy by up-regulating anti-inflammatory cytokines, reducing pro-inflammatory cytokines (PICs), attenuating nuclear factor-κB (NF-κB) p65 and NAD(P)H oxidase in the PVN of young spontaneously hypertensive rats (SHR). Young normotensive Wistar–Kyoto (WKY) and SHR rats received bilateral PVN infusions with NF–κB inhibitor pyrrolidine dithiocarbamate (PDTC) or vehicle for 4 weeks. SHR rats had higher mean arterial pressure and cardiac hypertrophy as indicated by increased whole heart weight/body weight ratio, whole heart weight/tibia length ratio, left ventricular weight/tibia length ratio, cardiomyocyte diameters of the left cardiac ventricle, and mRNA expressions of cardiac atrial natriuretic peptide (ANP) and beta-myosin heavy chain (β-MHC). These SHR rats had higher PVN levels of proinflammatory cytokines (PICs), reactive oxygen species (ROS), the chemokine monocyte chemoattractant protein-1 (MCP-1), NAD(P)H oxidase activity, mRNA expression of NOX-2 and NOX-4, and lower PVN IL-10, and higher plasma levels of PICs and NE, and lower plasma IL-10. PVN infusion of NF-κB inhibitor PDTC attenuated all these changes. These findings suggest that NF-κB activation in the PVN increases sympathoexcitation and hypertensive response, which are associated with the increases of PICs and oxidative stress in the PVN; PVN inhibition of NF-κB activity attenuates PICs and oxidative stress in the PVN, thereby attenuates hypertension and cardiac hypertrophy. - Highlights: • Spontaneously hypertensive rats exhibit neurohormonal excitation in the PVN. • PVN inhibition of NF-κB attenuates hypertension-induced cardiac hypertrophy. • PVN inhibition of NF-κB attenuates hypertension-induced neurohormonal excitation. • PVN inhibition of NF-κB attenuates hypertension-induced imbalance of cytokines

  6. Inhibition of NF-κB activity in the hypothalamic paraventricular nucleus attenuates hypertension and cardiac hypertrophy by modulating cytokines and attenuating oxidative stress

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Xiao-Jing [Department of Physiology and Pathophysiology, Xi' an Jiaotong University School of Basic Medical Sciences, Xi' an Jiaotong University Cardiovascular Research Center, Xi' an Jiaotong University Health Science Center, Xi' an 710061 (China); Zhang, Dong-Mei [Department of Physiology, Dalian Medical University, Dalian 116044 (China); Jia, Lin-Lin; Qi, Jie; Song, Xin-Ai; Tan, Hong [Department of Physiology and Pathophysiology, Xi' an Jiaotong University School of Basic Medical Sciences, Xi' an Jiaotong University Cardiovascular Research Center, Xi' an Jiaotong University Health Science Center, Xi' an 710061 (China); Cui, Wei [Department of Endocrinology and Metabolism, First Affiliated Hospital of Xi' an Jiaotong University, Xi' an Jiaotong University Health Science Center, Xi' an 710061 (China); Chen, Wensheng [Department of Cardiovascular Surgery, Xijing Hospital, Fourth Military Medical University, Xi' an 710032 (China); Zhu, Guo-Qing [Key Laboratory of Cardiovascular Disease and Molecular Intervention, Department of Physiology, Nanjing Medical University, Nanjing 210029 (China); Qin, Da-Nian, E-mail: dnqin@stu.edu.cn [Department of Physiology, Shantou University Medical College, Shantou 515041 (China); Kang, Yu-Ming, E-mail: ykang@mail.xjtu.edu.cn [Department of Physiology and Pathophysiology, Xi' an Jiaotong University School of Basic Medical Sciences, Xi' an Jiaotong University Cardiovascular Research Center, Xi' an Jiaotong University Health Science Center, Xi' an 710061 (China)

    2015-05-01

    We hypothesized that chronic inhibition of NF-κB activity in the hypothalamic paraventricular nucleus (PVN) delays the progression of hypertension and attenuates cardiac hypertrophy by up-regulating anti-inflammatory cytokines, reducing pro-inflammatory cytokines (PICs), attenuating nuclear factor-κB (NF-κB) p65 and NAD(P)H oxidase in the PVN of young spontaneously hypertensive rats (SHR). Young normotensive Wistar–Kyoto (WKY) and SHR rats received bilateral PVN infusions with NF–κB inhibitor pyrrolidine dithiocarbamate (PDTC) or vehicle for 4 weeks. SHR rats had higher mean arterial pressure and cardiac hypertrophy as indicated by increased whole heart weight/body weight ratio, whole heart weight/tibia length ratio, left ventricular weight/tibia length ratio, cardiomyocyte diameters of the left cardiac ventricle, and mRNA expressions of cardiac atrial natriuretic peptide (ANP) and beta-myosin heavy chain (β-MHC). These SHR rats had higher PVN levels of proinflammatory cytokines (PICs), reactive oxygen species (ROS), the chemokine monocyte chemoattractant protein-1 (MCP-1), NAD(P)H oxidase activity, mRNA expression of NOX-2 and NOX-4, and lower PVN IL-10, and higher plasma levels of PICs and NE, and lower plasma IL-10. PVN infusion of NF-κB inhibitor PDTC attenuated all these changes. These findings suggest that NF-κB activation in the PVN increases sympathoexcitation and hypertensive response, which are associated with the increases of PICs and oxidative stress in the PVN; PVN inhibition of NF-κB activity attenuates PICs and oxidative stress in the PVN, thereby attenuates hypertension and cardiac hypertrophy. - Highlights: • Spontaneously hypertensive rats exhibit neurohormonal excitation in the PVN. • PVN inhibition of NF-κB attenuates hypertension-induced cardiac hypertrophy. • PVN inhibition of NF-κB attenuates hypertension-induced neurohormonal excitation. • PVN inhibition of NF-κB attenuates hypertension-induced imbalance of cytokines

  7. Prenatal Acute Stress Attenuated Epileptiform Activities in Neonate Mice

    Directory of Open Access Journals (Sweden)

    Behnam Heshmatian

    2010-01-01

    Full Text Available Objective: Development of the central nervous system (CNS is dependent on interactionsbetween genetic and epigenetic factors, some of which could affect the susceptibilityof the developing brain to damaging insults. Gestational stress has been shown as a potentialfactor associated with higher risk of developing certain neurological and psychiatricdisorders. This study tested the hypothesis that maternal stress influences the risk ofepilepsy in offsprings.Materials and Methods: Pregnant mice were exposed to restraint stress twice a day forthree days at the start of the last week of gestation. Ten days after birth, the intact hippocampiof the newborn mice were excised and prepared for investigation. The hippocampiwere bathed in low magnesium artificial cerebrospinal fluid to induce field potential,and the subsequent spontaneous seizure-like events of the CA1 neurons were recorded.Plasma corticosterone was measured using a commercial radioimmunoassay (RIA kitand the values were expressed as μg/100 ml.Results: Both the number of recurrent seizures and the duration of seizure activity werereduced in the stressed group compared to the controls (p<0.001. Stress induced a significantrise in serum corticosterone levels in both pregnant mice and in their newbornpups (p<0.001.Conclusion: These findings suggest that acute prenatal stress, which may mimic acutestress in human pregnancy, is a likely factor affecting seizure control in childhood temporallobe epilepsy. The underlying inhibitory mechanism may be an increase in the level ofneurosteroids both in the blood and the brain.

  8. Activation of farnesoid X receptor attenuates hepatic injury in a murine model of alcoholic liver disease

    International Nuclear Information System (INIS)

    Highlights: •FXR activity was impaired by chronic ethanol ingestion in a murine model of ALD. •Activation of FXR attenuated alcohol-induced liver injury and steatosis. •Activation of FXR attenuated cholestasis and oxidative stress in mouse liver. -- Abstract: Alcoholic liver disease (ALD) is a common cause of advanced liver disease, and considered as a major risk factor of morbidity and mortality worldwide. Hepatic cholestasis is a pathophysiological feature observed in all stages of ALD. The farnesoid X receptor (FXR) is a member of the nuclear hormone receptor superfamily, and plays an essential role in the regulation of bile acid, lipid and glucose homeostasis. However, the role of FXR in the pathogenesis and progression of ALD remains largely unknown. Mice were fed Lieber-DeCarli ethanol diet or an isocaloric control diet. We used a specific agonist of FXR WAY-362450 to study the effect of pharmacological activation of FXR in alcoholic liver disease. In this study, we demonstrated that FXR activity was impaired by chronic ethanol ingestion in a murine model of ALD. Activation of FXR by specific agonist WAY-362450 protected mice from the development of ALD. We also found that WAY-362450 treatment rescued FXR activity, suppressed ethanol-induced Cyp2e1 up-regulation and attenuated oxidative stress in liver. Our results highlight a key role of FXR in the modulation of ALD development, and propose specific FXR agonists for the treatment of ALD patients

  9. Activation of farnesoid X receptor attenuates hepatic injury in a murine model of alcoholic liver disease

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Weibin [Department of Biochemistry and Molecular Biology, Shanghai Medical College, Fudan University, Shanghai 200032 (China); Institutes of Biomedical Science, Fudan University, Shanghai 200032 (China); Zhu, Bo; Peng, Xiaomin [Department of Biochemistry and Molecular Biology, Shanghai Medical College, Fudan University, Shanghai 200032 (China); Zhou, Meiling, E-mail: meilingzhou2012@gmail.com [Department of Radiology, Zhongshan Hospital of Fudan University and Shanghai Institute of Medical Imaging, Shanghai 200032 (China); Jia, Dongwei, E-mail: jiadongwei@fudan.edu.cn [Department of Biochemistry and Molecular Biology, Shanghai Medical College, Fudan University, Shanghai 200032 (China); Gu, Jianxin [Department of Biochemistry and Molecular Biology, Shanghai Medical College, Fudan University, Shanghai 200032 (China); Institutes of Biomedical Science, Fudan University, Shanghai 200032 (China)

    2014-01-03

    Highlights: •FXR activity was impaired by chronic ethanol ingestion in a murine model of ALD. •Activation of FXR attenuated alcohol-induced liver injury and steatosis. •Activation of FXR attenuated cholestasis and oxidative stress in mouse liver. -- Abstract: Alcoholic liver disease (ALD) is a common cause of advanced liver disease, and considered as a major risk factor of morbidity and mortality worldwide. Hepatic cholestasis is a pathophysiological feature observed in all stages of ALD. The farnesoid X receptor (FXR) is a member of the nuclear hormone receptor superfamily, and plays an essential role in the regulation of bile acid, lipid and glucose homeostasis. However, the role of FXR in the pathogenesis and progression of ALD remains largely unknown. Mice were fed Lieber-DeCarli ethanol diet or an isocaloric control diet. We used a specific agonist of FXR WAY-362450 to study the effect of pharmacological activation of FXR in alcoholic liver disease. In this study, we demonstrated that FXR activity was impaired by chronic ethanol ingestion in a murine model of ALD. Activation of FXR by specific agonist WAY-362450 protected mice from the development of ALD. We also found that WAY-362450 treatment rescued FXR activity, suppressed ethanol-induced Cyp2e1 up-regulation and attenuated oxidative stress in liver. Our results highlight a key role of FXR in the modulation of ALD development, and propose specific FXR agonists for the treatment of ALD patients.

  10. Epigallocatechin gallate (EGCG) attenuates infrasound-induced neuronal impairment by inhibiting microglia-mediated inflammation.

    Science.gov (United States)

    Cai, Jing; Jing, Da; Shi, Ming; Liu, Yang; Lin, Tian; Xie, Zhen; Zhu, Yi; Zhao, Haibo; Shi, Xiaodan; Du, Fang; Zhao, Gang

    2014-07-01

    Infrasound, a kind of common environmental noise and a major contributor of vibroacoustic disease, can induce the central nervous system (CNS) damage. However, no relevant anti-infrasound drugs have been reported yet. Our recent studies have shown that infrasound resulted in excessive microglial activation rapidly and sequential inflammation, revealing a potential role of microglia in infrasound-induced CNS damage. Epigallocatechin gallate (EGCG), a major bioactive component in green tea, has the capacity of protecting against various neurodegenerative diseases via an anti-inflammatory mechanism. However, it is still unknown to date whether EGCG acts on infrasound-induced microglial activation and neuronal damage. We showed that, after 1-, 2- or 5-day exposure of rats to 16 Hz, 130 dB infrasound (2 h/day), EGCG significantly inhibited infrasound-induced microglial activation in rat hippocampal region, evidenced by reduced expressions of Iba-1 (a marker for microglia) and proinflammatory cytokines (IL-1β, IL-6, IL-18 and TNF-α). Moreover, infrasound-induced neuronal apoptosis in rat hippocampi was significantly suppressed by EGCG. EGCG also inhibited infrasound-induced activation of primary microglia in vitro and decreased the levels of proinflammatory cytokines in the supernatants of microglial culture, which were toxic to cultured neurons. Furthermore, EGCG attenuated infrasound-induced increases in nuclear NF-κB p65 and phosphorylated IκBα, and ameliorated infrasound-induced decrease in IκB in microglia. Therefore, our study provides the first evidence that EGCG acts against infrasound-induced neuronal impairment by inhibiting microglia-mediated inflammation through a potential NF-κB pathway-related mechanism, suggesting that EGCG can be used as a promising drug for the treatment of infrasound-induced CNS damage. PMID:24746834

  11. Tff3 is Expressed in Neurons and Microglial Cells

    Directory of Open Access Journals (Sweden)

    Ting Fu

    2014-11-01

    Full Text Available Background/Aims: The trefoil factor family (TFF peptide TFF3 is typically secreted by mucous epithelia, but is also expressed in the immune system and the brain. It was the aim of this study to determine the cerebral cell types which express Tff3. Methods: Primary cultures from rat embryonic or neonatal cerebral cortex and hippocampus, respectively, were studied by means of RT-PCR and immunofluorescence. Moreover, Tff3 expression was localized by immunocytochemistry in sections of adult rat cerebellum. Results: Tff3 transcripts were detectable in neural cultures of both the cortex and the hippocampus as well as in glial cell-enriched cultures. Tff3 peptide co-localized with Map2 indicating an expression in neurons in vitro. The neuronal expression was confirmed by immunofluorescence studies of adult rat cerebellum. Furthermore, Tff3 peptide showed also a clear co-localization with Iba-1 in vitro typical of activated microglial cells. Conclusion: The neuronal expression of Tff3 is in line with a function of a typical neuropeptide influencing, e.g., fear, memory, depression and motoric skills. The expression in activated microglial cells, which is demonstrated here for the first time, points towards a possible function for Tff3 in immune reactions in the CNS. This opens a plethora of additional possible functions for Tff3 including synaptic plasticity and cognition as well as during neuroinflammatory diseases and psychiatric disorders.

  12. Preventive Effects of a Fermented Dairy Product against Alzheimer’s Disease and Identification of a Novel Oleamide with Enhanced Microglial Phagocytosis and Anti-Inflammatory Activity

    OpenAIRE

    Ano, Yasuhisa; Ozawa, Makiko; Kutsukake, Toshiko; Sugiyama, Shinya; Uchida, Kazuyuki; Yoshida, Aruto; Nakayama, Hiroyuki

    2015-01-01

    Despite the ever-increasing number of patients with dementia worldwide, fundamental therapeutic approaches to this condition have not been established. Epidemiological studies suggest that intake of fermented dairy products prevents cognitive decline in the elderly. However, the active compounds responsible for the effect remain to be elucidated. The present study aims to elucidate the preventive effects of dairy products on Alzheimer’s disease and to identify the responsible component. Here,...

  13. Glucocerebrosidase 1 deficient Danio rerio mirror key pathological aspects of human Gaucher disease and provide evidence of early microglial activation preceding alpha-synuclein-independent neuronal cell death

    OpenAIRE

    Keatinge, Marcus; Bui, Hai; Menke, Aswin; Chen, Yu-Chia; Sokol, Anna M.; Bai, Qing; Ellett, Felix; Da Costa, Marc; Burke, Derek; Gegg, Matthew; Trollope, Lisa; Payne, Thomas; McTighe, Aimee; Mortiboys, Heather; de Jager, Sarah

    2015-01-01

    Autosomal recessively inherited glucocerebrosidase 1 (GBA1) mutations cause the lysosomal storage disorder Gaucher's disease (GD). Heterozygous GBA1 mutations (GBA1 +/−) are the most common risk factor for Parkinson's disease (PD). Previous studies typically focused on the interaction between the reduction of glucocerebrosidase (enzymatic) activity in GBA1 +/− carriers and alpha-synuclein-mediated neurotoxicity. However, it is unclear whether other mechanisms also contribute to the increased ...

  14. Propofol and magnesium attenuate isoflurane-induced caspase-3 activation via inhibiting mitochondrial permeability transition pore

    Directory of Open Access Journals (Sweden)

    Zhang Yiying

    2012-08-01

    Full Text Available Abstract Background The inhalation anesthetic isoflurane has been shown to open the mitochondrial permeability transition pore (mPTP and induce caspase activation and apoptosis, which may lead to learning and memory impairment. Cyclosporine A, a blocker of mPTP opening might attenuate the isoflurane-induced mPTP opening, lessening its ripple effects. Magnesium and anesthetic propofol are also mPTP blockers. We therefore set out to determine whether propofol and magnesium can attenuate the isoflurane-induced caspase activation and mPTP opening. Methods We investigated the effects of magnesium sulfate (Mg2+, propofol, and isoflurane on the opening of mPTP and caspase activation in H4 human neuroglioma cells stably transfected to express full-length human amyloid precursor protein (APP (H4 APP cells and in six day-old wild-type mice, employing Western blot analysis and flowcytometry. Results Here we show that Mg2+ and propofol attenuated the isoflurane-induced caspase-3 activation in H4-APP cells and mouse brain tissue. Moreover, Mg2+ and propofol, the blockers of mPTP opening, mitigated the isoflurane-induced mPTP opening in the H4-APP cells. Conclusion These data illustrate that Mg2+ and propofol may ameliorate the isoflurane-induced neurotoxicity by inhibiting its mitochondrial dysfunction. Pending further studies, these findings may suggest the use of Mg2+ and propofol in preventing and treating anesthesia neurotoxicity.

  15. CSF markers of Alzheimer’s pathology and microglial activation are associated with altered white matter microstructure in asymptomatic adults at risk for Alzheimer’s disease

    Science.gov (United States)

    Melah, Kelsey E; Lu, Sharon Yuan-Fu; Hoscheidt, Siobhan M; Alexander, Andrew L; Adluru, Nagesh; Destiche, Daniel J; Carlsson, Cynthia M; Zetterberg, Henrik; Blennow, Kaj; Okonkwo, Ozioma C; Gleason, Carey E; Dowling, N Maritza; Bratzke, Lisa C; Rowley, Howard A; Sager, Mark A; Asthana, Sanjay; Johnson, Sterling C; Bendlin, Barbara B

    2015-01-01

    Background The immune response in Alzheimer’s disease (AD) involves activation of microglia which may remove β-amyloid. However, overproduction of inflammatory compounds may exacerbate neural damage in Alzheimer’s disease. AD pathology accumulates years before diagnosis, yet the extent to which neuroinflammation is involved in the earliest disease stages is unknown. Objective To determine whether neuroinflammation exacerbates neural damage in preclinical AD. Methods We utilized cerebrospinal fluid (CSF) and magnetic resonance imaging collected in 192 asymptomatic late-middle-aged adults (mean age=60.98 years). Neuroinflammatory markers chitinase-3-like protein 1 (YKL-40) and monocyte chemoattractant protein-1 (MCP-1) in CSF were utilized as markers of neuroinflammation. Neural cell damage was assessed using CSF neurofilament light chain protein (NFL), CSF total tau (T-Tau), and neural microstructure assessed with diffusion tensor imaging (DTI). With regard to AD pathology, CSF Aβ42 and tau phosphorylated at threonine 181 (P-Tau181) were used as markers of amyloid and tau pathology, respectively. We hypothesized that higher YKL-40 and MCP-1 in the presence of AD pathology would be associated with higher NFL, T-Tau, and altered microstructure on DTI. Results Neuroinflammation was associated with markers of neural damage. Higher CSF YKL-40 was associated with both higher CSF NFL and T-Tau. Inflammation interacted with AD pathology, such that greater MCP-1 and lower Aβ42 was associated with altered microstructure in bilateral frontal and right temporal lobe and that greater MCP-1 and greater P-Tau181 was associated with altered microstructure in precuneus. Conclusion Inflammation may play a role in neural damage in preclinical AD. PMID:26836182

  16. PI3k/Akt signalling pathway plays a crucial role in the anti-inflammatory effects of curcumin in LPS-activated microglia.

    Science.gov (United States)

    Cianciulli, Antonia; Calvello, Rosa; Porro, Chiara; Trotta, Teresa; Salvatore, Rosaria; Panaro, Maria Antonietta

    2016-07-01

    Microglia are resident macrophages in the central nervous system (CNS) deputed to defend against pathogens. Persistent or acute inflammation of microglia leads to CNS disorders, so regulation of pro-inflammatory responses of microglial cells is thought to be a promising therapeutic strategy to attenuate abnormal inflammatory responses observed in neurodegenerative disease. We hypothesized that curcumin supplementation could reduce the inflammatory responses of activated microglial cells modulating PI3K/Akt pathway. Different curcumin concentrations were administered as BV-2 microglia pre-treatment 1h prior to LPS stimulation. Nitric oxide (NO) and inducible nitric oxide synthase (iNOS) expression were determined by Griess reagent and western blotting, respectively. Inflammatory cytokines release was evaluated by ELISA and qRT-PCR. PI3K/Akt expression was analyzed by western blotting analysis. Curcumin significantly attenuated, in a dose-dependent manner, LPS-induced release of NO and pro-inflammatory cytokines, as well as iNOS expression. Interestingly, curcumin was able to reduce, again in a dose-dependent manner, PI3K/Akt phosphorylation as well as NF-κB activation in LPS-activated microglial cells. Overall these results suggest that curcumin plays an important role in the attenuation of LPS-induced inflammatory responses in microglial cells and that the mechanisms involve down-regulation of the PI3K/Akt signalling. PMID:27208432

  17. Estuarine morphometry governs optically active substances, Kd(PAR) and beam attenuation

    DEFF Research Database (Denmark)

    Lund-Hansen, L. C.; Nielsen, J. M.; Blüthgen, J.;

    2013-01-01

    this spatial distribution. Partition and multiple regression analyses showed that Chl-a governed Kd(PAR) and beam attenuation coefficient in both estuaries. Significant, high correlations were obtained by multiple regression analyses in the estimation of Kd(PAR) and beam attenuation coefficients in the two......Data on optical properties such as diffuse attenuation coefficient Kd(PAR), beam attenuation coefficient (cp) and the optically active constituents (OACs) CDOM, Chl-a and suspended particulate matter were obtained in a Danish temperate coastal plain estuary (56°N) and a Vietnamese tropical ria (12...

  18. Microglial priming through the lung-brain axis: the role of air pollution-induced circulating factors.

    Science.gov (United States)

    Mumaw, Christen L; Levesque, Shannon; McGraw, Constance; Robertson, Sarah; Lucas, Selita; Stafflinger, Jillian E; Campen, Matthew J; Hall, Pamela; Norenberg, Jeffrey P; Anderson, Tamara; Lund, Amie K; McDonald, Jacob D; Ottens, Andrew K; Block, Michelle L

    2016-05-01

    Air pollution is implicated in neurodegenerative disease risk and progression and in microglial activation, but the mechanisms are unknown. In this study, microglia remained activated 24 h after ozone (O3) exposure in rats, suggesting a persistent signal from lung to brain. Ex vivo analysis of serum from O3-treated rats revealed an augmented microglial proinflammatory response and β-amyloid 42 (Aβ42) neurotoxicity independent of traditional circulating cytokines, where macrophage-1 antigen-mediated microglia proinflammatory priming. Aged mice exhibited reduced pulmonary immune profiles and the most pronounced neuroinflammation and microglial activation in response to mixed vehicle emissions. Consistent with this premise, cluster of differentiation 36 (CD36)(-/-) mice exhibited impaired pulmonary immune responses concurrent with augmented neuroinflammation and microglial activation in response to O3 Further, aging glia were more sensitive to the proinflammatory effects of O3 serum. Together, these findings outline the lung-brain axis, where air pollutant exposures result in circulating, cytokine-independent signals present in serum that elevate the brain proinflammatory milieu, which is linked to the pulmonary response and is further augmented with age.-Mumaw, C. L., Levesque, S., McGraw, C., Robertson, S., Lucas, S., Stafflinger, J. E., Campen, M. J., Hall, P., Norenberg, J. P., Anderson, T., Lund, A. K., McDonald, J. D., Ottens, A. K., Block, M. L. Microglial priming through the lung-brain axis: the role of air pollution-induced circulating factors. PMID:26864854

  19. Essential role of MFG-E8 for phagocytic properties of microglial cells.

    Directory of Open Access Journals (Sweden)

    Yong Liu

    Full Text Available Milk fat globule factor-E8 (MFG-E8 has been regarded as a key factor involved in the phagocytosis of apoptotic cells. We induced a lentivirus into the microglial cells for the augmentation or abrogation of MFG-E8 expression in mouse microglial cells, and investigated phagocytosis of phosphatidylserine tagged human red blood cells (hRBCs in co-cultures. Increased MFG-E8 levels were associated with a significant increase in phagocytic activity compared to the controls. Conversely, phagocytosis dramitically decreased due to the abrogation of MFG-E8. In addition, the expression of the inflammatory cytokines, TNF-α and IL-1β, also increased or decreased in the microglial cells with the augmentation or abrogation of MFG-E8, respectively. Our findings indicate that the enhanced expression of MFG-E8 could increase phagocytosis of apoptotic cells; conversely, the rate of phagocytosis and the expression of inflammatory cytokines decreased when MFG-E8 expression was knocked down. Our results confirm that MFG-E8 plays an important role in phagocytosis, and possibly serves as an essential signal molecule for microglial cells.

  20. Attenuation of signaling pathways stimulated by pathologically activated FGF-receptor 2 mutants prevents craniosynostosis.

    Science.gov (United States)

    Eswarakumar, V P; Ozcan, F; Lew, E D; Bae, J H; Tomé, F; Booth, C J; Adams, D J; Lax, I; Schlessinger, J

    2006-12-01

    Craniosynostosis, the fusion of one or more of the sutures of the skull vault before the brain completes its growth, is a common (1 in 2,500 births) craniofacial abnormality, approximately 20% of which occurrences are caused by gain-of-function mutations in FGF receptors (FGFRs). We describe a genetic and pharmacological approach for the treatment of a murine model system of Crouzon-like craniosynostosis induced by a dominant mutation in Fgfr2c. Using genetically modified mice, we demonstrate that premature fusion of sutures mediated by Crouzon-like activated Fgfr2c mutant is prevented by attenuation of signaling pathways by selective uncoupling between the docking protein Frs2alpha and activated Fgfr2c, resulting in normal skull development. We also demonstrate that attenuation of Fgfr signaling in a calvaria organ culture with an Fgfr inhibitor prevents premature fusion of sutures without adversely affecting calvaria development. These experiments show that attenuation of FGFR signaling by pharmacological intervention could be applied for the treatment of craniosynostosis or other severe bone disorders caused by mutations in FGFRs that currently have no treatment. PMID:17132737

  1. Ginsenoside Rg1 Attenuates Isoflurane-induced Caspase-3 Activation via Inhibiting Mitochondrial Dysfunction

    Institute of Scientific and Technical Information of China (English)

    MIAO Hui Hui; ZHEN Yu; DING Guan Nan; HONG Fang Xiao; XIE Zhong Cong; TIAN Ming

    2015-01-01

    Objective The inhalation anesthetic isoflurane has been shown to induce mitochondrial dysfunction and caspase activation, which may lead to learning and memory impairment. Ginsenoside Rg1 is reported to be neuroprotective. We therefore set out to determine whether ginsenoside Rg1 can attenuate isoflurane-induced caspase activation via inhibiting mitochondrial dysfunction. Methods We investigated the effects of ginsenoside Rg1 at concentrations of 12.5, 25, and 50 µmol/L and pretreatment times of 12 h and 24 h on isoflurane-induced caspase-3 activation in H4 naïve and stably transfected H4 human neuroglioma cells that express full-length human amyloid precursor protein (APP) (H4-APP cells). For mitochondrial dysfunction, we assessed mitochondrial permeability transition pore (mPTP) and adenosine-5’-triphosphate (ATP) levels. We employed Western blot analysis, chemiluminescence, and flowcytometry. Results Here we show that pretreatment with 50 µmol/L ginsenoside Rg1 for 12 h attenuated isoflurane-induced caspase-3 activation and mitochondrial dysfunction in H4-APP cells, while pretreatment with 25 and 50 µmol/L ginsenoside Rg1 for 24 h attenuated isoflurane-induced caspase-3 activation and mitochondrial dysfunction in both H4 naïve and H4-APP cells. Conclusion These data suggest that ginsenoside Rg1 may ameliorate isoflurane-induced caspase-3 activation by inhibiting mitochondrial dysfunction. Pending further studies, these findings might recommend the use of ginsenoside Rg1 in preventing and treating isoflurane-induced neurotoxicity.

  2. Predicting trace organic compound attenuation with spectroscopic parameters in powdered activated carbon processes.

    Science.gov (United States)

    Ziska, Austin D; Park, Minkyu; Anumol, Tarun; Snyder, Shane A

    2016-08-01

    The removal of trace organic compounds (TOrCs) is of growing interest in water research and society. Powdered activated carbon (PAC) has been proven to be an effective method of removal for TOrCs in water, with the degree of effectiveness depending on dosage, contact time, and activated carbon type. In this study, the attenuation of TOrCs in three different secondary wastewater effluents using four PAC materials was studied in order to elucidate the effectiveness and efficacy of PAC for TOrC removal. With the notable exception of hydrochlorothiazide, all 14 TOrC indicators tested in this study exhibited a positive correlation of removal rate with their log Dow values, demonstrating that the main adsorption mechanism was hydrophobic interaction. As a predictive model, the modified Chick-Watson model, often used for the prediction of microorganism inactivation by disinfectants, was applied. The applied model exhibited good predictive power for TOrC attenuation by PAC in wastewater. In addition, surrogate models based upon spectroscopic measurements including UV absorbance at 254 nm and total fluorescence were applied to predict TOrC removal by PAC. The surrogate model was found to provide an excellent prediction of TOrC attenuation for all combinations of water quality and PAC type included in this study. The success of spectrometric parameters as surrogates in predicting TOrC attenuation by PAC are particularly useful because of their potential application in real-time on-line sensor monitoring and process control at full-scale water treatment plants, which could lead to significantly reduced operator response times and PAC operational optimization. PMID:27174829

  3. Hormetic Effect of Berberine Attenuates the Anticancer Activity of Chemotherapeutic Agents.

    Science.gov (United States)

    Bao, Jiaolin; Huang, Borong; Zou, Lidi; Chen, Shenghui; Zhang, Chao; Zhang, Yulin; Chen, Meiwan; Wan, Jian-Bo; Su, Huanxing; Wang, Yitao; He, Chengwei

    2015-01-01

    Hormesis is a phenomenon of biphasic dose response characterized by exhibiting stimulatory or beneficial effects at low doses and inhibitory or toxic effects at high doses. Increasing numbers of chemicals of various types have been shown to induce apparent hormetic effect on cancer cells. However, the underlying significance and mechanisms remain to be elucidated. Berberine, one of the major active components of Rhizoma coptidis, has been manifested with notable anticancer activities. This study aims to investigate the hormetic effect of berberine and its influence on the anticancer activities of chemotherapeutic agents. Our results demonstrated that berberine at low dose range (1.25 ~ 5 μM) promoted cell proliferation to 112% ~170% of the untreated control in various cancer cells, while berberine at high dose rage (10 ~ 80 μM) inhibited cell proliferation. Further, we observed that co-treatment with low dose berberine could significantly attenuate the anticancer activity of chemotherapeutic agents, including fluorouracil (5-FU), camptothecin (CPT), and paclitaxel (TAX). The hormetic effect and thereby the attenuated anticancer activity of chemotherapeutic drugs by berberine may attributable to the activated protective stress response in cancer cells triggered by berberine, as evidenced by up-regulated MAPK/ERK1/2 and PI3K/AKT signaling pathways. These results provided important information to understand the potential side effects of hormesis, and suggested cautious application of natural compounds and relevant herbs in adjuvant treatment of cancer.

  4. Hormetic Effect of Berberine Attenuates the Anticancer Activity of Chemotherapeutic Agents.

    Directory of Open Access Journals (Sweden)

    Jiaolin Bao

    Full Text Available Hormesis is a phenomenon of biphasic dose response characterized by exhibiting stimulatory or beneficial effects at low doses and inhibitory or toxic effects at high doses. Increasing numbers of chemicals of various types have been shown to induce apparent hormetic effect on cancer cells. However, the underlying significance and mechanisms remain to be elucidated. Berberine, one of the major active components of Rhizoma coptidis, has been manifested with notable anticancer activities. This study aims to investigate the hormetic effect of berberine and its influence on the anticancer activities of chemotherapeutic agents. Our results demonstrated that berberine at low dose range (1.25 ~ 5 μM promoted cell proliferation to 112% ~170% of the untreated control in various cancer cells, while berberine at high dose rage (10 ~ 80 μM inhibited cell proliferation. Further, we observed that co-treatment with low dose berberine could significantly attenuate the anticancer activity of chemotherapeutic agents, including fluorouracil (5-FU, camptothecin (CPT, and paclitaxel (TAX. The hormetic effect and thereby the attenuated anticancer activity of chemotherapeutic drugs by berberine may attributable to the activated protective stress response in cancer cells triggered by berberine, as evidenced by up-regulated MAPK/ERK1/2 and PI3K/AKT signaling pathways. These results provided important information to understand the potential side effects of hormesis, and suggested cautious application of natural compounds and relevant herbs in adjuvant treatment of cancer.

  5. Neurons and astroglia govern microglial endotoxin tolerance through macrophage colony-stimulating factor receptor-mediated ERK1/2 signals.

    Science.gov (United States)

    Chu, Chun-Hsien; Wang, Shijun; Li, Chia-Ling; Chen, Shih-Heng; Hu, Chih-Fen; Chung, Yi-Lun; Chen, Shiou-Lan; Wang, Qingshan; Lu, Ru-Band; Gao, Hui-Ming; Hong, Jau-Shyong

    2016-07-01

    Endotoxin tolerance (ET) is a reduced responsiveness of innate immune cells like macrophages/monocytes to an endotoxin challenge following a previous encounter with the endotoxin. Although ET in peripheral systems has been well studied, little is known about ET in the brain. The present study showed that brain immune cells, microglia, being different from peripheral macrophages, displayed non-cell autonomous mechanisms in ET formation. Specifically, neurons and astroglia were indispensable for microglial ET. Macrophage colony-stimulating factor (M-CSF) secreted from these non-immune cells was essential for governing microglial ET. Neutralization of M-CSF deprived the neuron-glia conditioned medium of its ability to enable microglia to form ET when microglia encountered two lipopolysaccharide (LPS) treatments. Recombinant M-CSF protein rendered enriched microglia refractory to the second LPS challenge leading to microglial ET. Activation of microglial M-CSF receptor (M-CSFR; also known as CSF1R) and the downstream ERK1/2 signals was responsible for M-CSF-mediated microglial ET. Endotoxin-tolerant microglia in neuron-glia cultures displayed M2-like polarized phenotypes, as shown by upregulation of M2 marker Arg-1, elevated production of anti-inflammatory cytokine interleukin 10, and decreased secretion of pro-inflammatory mediators (tumor necrosis factor α, nitric oxide, prostaglandin E2 and interleukin 1β). Endotoxin-tolerant microglia protected neurons against LPS-elicited inflammatory insults, as shown by reduced neuronal damages in LPS pre-treatment group compared with the group without LPS pre-treatment. Moreover, while neurons and astroglia became injured during chronic neuroinflammation, microglia failed to form ET. Thus, this study identified a distinct non-cell autonomous mechanism of microglial ET. Interactions of M-CSF secreted by neurons and astroglia with microglial M-CSFR programed microglial ET. Loss of microglial ET could be an important

  6. Minocycline Transiently Reduces Microglia/Macrophage Activation but Exacerbates Cognitive Deficits Following Repetitive Traumatic Brain Injury in the Neonatal Rat.

    Science.gov (United States)

    Hanlon, Lauren A; Huh, Jimmy W; Raghupathi, Ramesh

    2016-03-01

    Elevated microglial/macrophage-associated biomarkers in the cerebrospinal fluid of infant victims of abusive head trauma (AHT) suggest that these cells play a role in the pathophysiology of the injury. In a model of AHT in 11-day-old rats, 3 impacts (24 hours apart) resulted in spatial learning and memory deficits and increased brain microglial/macrophage reactivity, traumatic axonal injury, neuronal degeneration, and cortical and white-matter atrophy. The antibiotic minocycline has been effective in decreasing injury-induced microglial/macrophage activation while simultaneously attenuating cellular and functional deficits in models of neonatal hypoxic ischemia, but the potential for this compound to rescue deficits after impact-based trauma to the immature brain remains unexplored. Acute minocycline administration in this model of AHT decreased microglial/macrophage reactivity in the corpus callosum of brain-injured animals at 3 days postinjury, but this effect was lost by 7 days postinjury. Additionally, minocycline treatment had no effect on traumatic axonal injury, neurodegeneration, tissue atrophy, or spatial learning deficits. Interestingly, minocycline-treated animals demonstrated exacerbated injury-induced spatial memory deficits. These results contrast with previous findings in other models of brain injury and suggest that minocycline is ineffective in reducing microglial/macrophage activation and ameliorating injury-induced deficits following repetitive neonatal traumatic brain injury. PMID:26825312

  7. Resting microglial cells exhibit tubular membrane protrusions

    Directory of Open Access Journals (Sweden)

    Ulrike Gimsa

    2002-11-01

    Full Text Available Nano- and microtubular structures have recently become a subject of increasing interest due to their importance in biology and medicine as well as their technological potential. Such structures have been observed in anorganic (Iijima, 1991 as well as in organic (Schnur 1993; Oda et al. 1991 systems. Micro- and nanotubular protrusions of bilayer membranes have been found in cells (Kralj-Iglic et al. 1998; Kralj-Iglic et al. 2001a and phospholipid vesicles (Kralj-Iglic et al. 2002; Kralj-Iglic et al. 2001b. In this work we describe membrane protrusions in microglial cells.

  8. Direct and indirect pharmacological modulation of CCL2/CCR2 pathway results in attenuation of neuropathic pain - In vivo and in vitro evidence.

    Science.gov (United States)

    Piotrowska, Anna; Kwiatkowski, Klaudia; Rojewska, Ewelina; Slusarczyk, Joanna; Makuch, Wioletta; Basta-Kaim, Agnieszka; Przewlocka, Barbara; Mika, Joanna

    2016-08-15

    The repeated administration of microglial inhibitor (minocycline) and CCR2 antagonist (RS504393) attenuated the neuropathic pain symptoms in rats following chronic constriction injury of the sciatic nerve, which was associated with decreased spinal microglia activation and the protein level of CCL2 and CCR2. Furthermore, in microglia primary cell cultures minocycline downregulated both CCL2 and CCR2 protein levels after lipopolysaccharide-stimulation. Additionally, in astroglia primary cell cultures minocycline decreased the expression of CCL2, but not CCR2. Our results provide new evidence that modulation of CCL2/CCR2 pathway by microglial inhibitor as well as CCR2 antagonist is effective for neuropathic pain development in rats. PMID:27397071

  9. Microglial Signaling in Chronic Pain with a Special Focus on Caspase 6, p38 MAP Kinase, and Sex Dependence.

    Science.gov (United States)

    Berta, T; Qadri, Y J; Chen, G; Ji, R R

    2016-09-01

    Microglia are the resident immune cells in the spinal cord and brain. Mounting evidence suggests that activation of microglia plays an important role in the pathogenesis of chronic pain, including chronic orofacial pain. In particular, microglia contribute to the transition from acute pain to chronic pain, as inhibition of microglial signaling reduces pathologic pain after inflammation, nerve injury, and cancer but not baseline pain. As compared with inflammation, nerve injury induces much more robust morphologic activation of microglia, termed microgliosis, as shown by increased expression of microglial markers, such as CD11b and IBA1. However, microglial signaling inhibitors effectively reduce inflammatory pain and neuropathic pain, arguing against the importance of morphologic activation of microglia in chronic pain sensitization. Importantly, microglia enhance pain states via secretion of proinflammatory and pronociceptive mediators, such as tumor necrosis factor α, interleukins 1β and 18, and brain-derived growth factor. Mechanistically, these mediators have been shown to enhance excitatory synaptic transmission and suppress inhibitory synaptic transmission in the pain circuits. While early studies suggested a predominant role of microglia in the induction of chronic pain, further studies have supported a role of microglia in the maintenance of chronic pain. Intriguingly, recent studies show male-dominant microglial signaling in some neuropathic pain and inflammatory pain states, although both sexes show identical morphologic activation of microglia after nerve injury. In this critical review, we provide evidence to show that caspase 6-a secreted protease that is expressed in primary afferent axonal terminals surrounding microglia-is a robust activator of microglia and induces profound release of tumor necrosis factor α from microglia via activation of p38 MAP kinase. The authors also show that microglial caspase 6/p38 signaling is male dominant in some

  10. Amiloride lowers blood pressure and attenuates urine plasminogen activation in patients with treatment-resistant hypertension

    DEFF Research Database (Denmark)

    Stolzenburg Oxlund, Christina; Buhl, Kristian Bergholt; Jacobsen, Ib A;

    2014-01-01

    /proteinuria to resistant hypertension. Amiloride, an ENaC inhibitor, inhibits urokinase-type plasminogen activator. We hypothesized that amiloride (1) reduces blood pressure (BP); (2) attenuates plasminogen-to-plasmin activation; and (3) inhibits urine urokinase-type plasminogen activator in patients with resistant...... hypertension and type 2 diabetes mellitus (T2DM).In an open-label, non-randomized, 8-week intervention study, a cohort (n = 80) of patients with resistant hypertension and T2DM were included. Amiloride (5 mg/d) was added to previous triple antihypertensive treatment (including a diuretic and an inhibitor...... urine, with a tendency toward reduction in activity after amiloride treatment. Amiloride lowers BP, urine plasminogen excretion and activation, and albumin/creatinine ratio, and is a relevant add-on medication for the treatment of resistant hypertension in patients with T2DM and microalbuminuria....

  11. Deep brain stimulation of the nucleus accumbens shell attenuates cocaine reinstatement through local and antidromic activation.

    Science.gov (United States)

    Vassoler, Fair M; White, Samantha L; Hopkins, Thomas J; Guercio, Leonardo A; Espallergues, Julie; Berton, Olivier; Schmidt, Heath D; Pierce, R Christopher

    2013-09-01

    Accumbal deep brain stimulation (DBS) is a promising therapeutic modality for the treatment of addiction. Here, we demonstrate that DBS in the nucleus accumbens shell, but not the core, attenuates cocaine priming-induced reinstatement of drug seeking, an animal model of relapse, in male Sprague Dawley rats. Next, we compared DBS of the shell with pharmacological inactivation. Results indicated that inactivation using reagents that influenced (lidocaine) or spared (GABA receptor agonists) fibers of passage blocked cocaine reinstatement when administered into the core but not the shell. It seems unlikely, therefore, that intrashell DBS influences cocaine reinstatement by inactivating this nucleus or the fibers coursing through it. To examine potential circuit-wide changes, c-Fos immunohistochemistry was used to examine neuronal activation following DBS of the nucleus accumbens shell. Intrashell DBS increased c-Fos induction at the site of stimulation as well as in the infralimbic cortex, but had no effect on the dorsal striatum, prelimbic cortex, or ventral pallidum. Recent evidence indicates that accumbens DBS antidromically stimulates axon terminals, which ultimately activates GABAergic interneurons in cortical areas that send afferents to the shell. To test this hypothesis, GABA receptor agonists (baclofen/muscimol) were microinjected into the anterior cingulate, and prelimbic or infralimbic cortices before cocaine reinstatement. Pharmacological inactivation of all three medial prefrontal cortical subregions attenuated the reinstatement of cocaine seeking. These results are consistent with DBS of the accumbens shell attenuating cocaine reinstatement via local activation and/or activation of GABAergic interneurons in the medial prefrontal cortex via antidromic stimulation of cortico-accumbal afferents. PMID:24005296

  12. Elevated NF-κB activation is conserved in human myocytes cultured from obese type 2 diabetic patients and attenuated by AMP-activated protein kinase

    DEFF Research Database (Denmark)

    Green, Charlotte Jane; Pedersen, Maria; Pedersen, Bente K;

    2011-01-01

    To examine whether the inflammatory phenotype found in obese and diabetic individuals is preserved in isolated, cultured myocytes and to assess the effectiveness of pharmacological AMP-activated protein kinase (AMPK) activation upon the attenuation of inflammation in these myocytes....

  13. The amelioration of phagocytic ability in microglial cells by curcumin through the inhibition of EMF-induced pro-inflammatory responses

    OpenAIRE

    He, Gen-Lin; Liu, Yong; Min LI; Chen, Chun-Hai; Gao, Peng; Yu, Zheng-Ping; Yang, Xue-Sen

    2014-01-01

    Background Insufficient clearance by microglial cells, prevalent in several neurological conditions and diseases, is intricately intertwined with MFG-E8 expression and inflammatory responses. Electromagnetic field (EMF) exposure can elicit the pro-inflammatory activation and may also trigger an alteration of the clearance function in microglial cells. Curcumin has important roles in the anti-inflammatory and phagocytic process. Here, we evaluated the ability of curcumin to ameliorate the phag...

  14. Alpha 1 Antitrypsin Inhibits Dendritic Cell Activation and Attenuates Nephritis in a Mouse Model of Lupus.

    Science.gov (United States)

    Elshikha, Ahmed S; Lu, Yuanqing; Chen, Mong-Jen; Akbar, Mohammad; Zeumer, Leilani; Ritter, Andrea; Elghamry, Hanaa; Mahdi, Mahmoud A; Morel, Laurence; Song, Sihong

    2016-01-01

    Systemic lupus erythematosus (SLE) is an autoimmune disorder with a worldwide distribution and considerable mortality and morbidity. Although the pathogenesis of this disease remains elusive, over-reactive dendritic cells (DCs) play a critical role in the disease development. It has been shown that human alpha-1 antitrypsin (hAAT) has protective effects in type 1 diabetes and rheumatoid arthritis mouse models. In the present study, we tested the effect of AAT on DC differentiation and functions, as well as its protective effect in a lupus-prone mouse model. We showed that hAAT treatment significantly inhibited LPS (TLR4 agonist) and CpG (TLR9 agonist) -induced bone-marrow (BM)-derived conventional and plasmacytoid DC (cDC and pDC) activation and reduced the production of inflammatory cytokines including IFN-I, TNF-α and IL-1β. In MRL/lpr mice, hAAT treatment significantly reduced BM-derived DC differentiation, serum autoantibody levels, and importantly attenuated renal pathology. Our results for the first time demonstrate that hAAT inhibits DC activation and function, and it also attenuates autoimmunity and renal damage in the MRL/lpr lupus model. These results imply that hAAT has a therapeutic potential for the treatment of SLE in humans. PMID:27232337

  15. Regulatory Effects of Caffeic Acid Phenethyl Ester on Neuroinflammation in Microglial Cells

    OpenAIRE

    Cheng-Fang Tsai; Yueh-Hsiung Kuo; Wei-Lan Yeh; Caren Yu-Ju Wu; Hsiao-Yun Lin; Sheng-Wei Lai; Yu-Shu Liu; Ling-Hsuan Wu; Jheng-Kun Lu; Dah-Yuu Lu

    2015-01-01

    Microglial activation has been widely demonstrated to mediate inflammatory processes that are crucial in several neurodegenerative disorders. Pharmaceuticals that can deliver direct inhibitory effects on microglia are therefore considered as a potential strategy to counter balance neurodegenerative progression. Caffeic acid phenethyl ester (CAPE), a natural phenol in honeybee propolis, is known to possess antioxidant, anti-inflammatory and anti-microbial properties. Accordingly, the current ...

  16. Impact attenuation during weight bearing activities in barefoot vs. shod conditions: a systematic review.

    Science.gov (United States)

    Fong Yan, Alycia; Sinclair, Peter J; Hiller, Claire; Wegener, Caleb; Smith, Richard M

    2013-06-01

    Although it could be perceived that there is extensive research on the impact attenuation characteristics of shoes, the approach and findings of researchers in this area are varied. This review aimed to clarify the effect of shoes on impact attenuation to the foot and lower leg and was limited to those studies that compared the shoe condition(s) with barefoot. A systematic search of the literature yielded 26 studies that investigated vertical ground reaction force, axial tibial acceleration, loading rate and local plantar pressures. Meta-analyses of the effect of shoes on each variable during walking and running were performed using the inverse variance technique. Variables were collected at their peak or at the impact transient, but when grouped together as previous comparisons have done, shoes reduced local plantar pressure and tibial acceleration, but did not affect vertical force or loading rate for walking. During running, shoes reduced tibial acceleration but did not affect loading rate or vertical force. Further meta-analyses were performed, isolating shoe type and when the measurements were collected. Athletic shoes reduced peak vertical force during walking, but increased vertical force at the impact transient and no change occurred for the other variables. During running, athletic shoes reduced loading rate but did not affect vertical force. The range of variables examined and variety of measurements used appears to be a reason for the discrepancies across the literature. The impact attenuating effect of shoes has potentially both adverse and beneficial effects depending on the variable and activity under investigation. PMID:23245643

  17. Hexane fraction of Zingiberis Rhizoma Crudus extract inhibits the production of nitric oxide and proinflammatory cytokines in LPS-stimulated BV2 microglial cells via the NF-kappaB pathway.

    Science.gov (United States)

    Jung, Hyo Won; Yoon, Cheol-Ho; Park, Kwon Moo; Han, Hyung Soo; Park, Yong-Ki

    2009-06-01

    Excessive production of inflammatory mediators such as nitric oxide (NO), prostaglandin E(2) (PGE2), and proinflammatory cytokines, including tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) from activated microglia contributes to uncontrolled inflammation in neurodegenerative diseases. It seems possible that treatment with anti-inflammatory agents, including plants used in Oriental medicine, might delay the progression of neurodegeneration through the inhibition of microglial activation. The present study is focused on the inhibitory effect of the rhizome hexane fraction extract of Zingiber officinale Roscoe (ginger hexan extract; GHE) on the production of inflammatory mediators such as NO, PGE(2), and proinflammatory cytokines in lipopolysaccharide (LPS)-stimulated BV-2 cells, a mouse microglial cell line. GHE significantly inhibited the excessive production of NO, PGE(2), TNF-alpha, and IL-1beta in LPS-stimulated BV2 cells. In addition, GHE attenuated the mRNA expressions and protein levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and proinflammatory cytokines. The molecular mechanisms that underlie GHE-mediated attenuation are related to the inhibition of the phosphorylation of three mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinases 1 and 2 (ERK1/2), p38 MAPK, and c-Jun N-terminal kinase (JNK), and the activation of nuclear factor-kappaB (NF-kappaB). Our results indicate that GHE exhibits anti-inflammatory properties by suppressing the transcription of inflammatory mediator genes through the MAPK and NF-kappaB signaling pathways. The anti-inflammatory properties of GHE may make it useful as a therapeutic candidate for the treatment of human neurodegenerative diseases. PMID:19233241

  18. Antiulcer Effect of Extract/Fractions of Eruca sativa : Attenuation of Urease Activity.

    Science.gov (United States)

    Khan, Haroon; Khan, Murad Ali

    2014-03-19

    Eruca sativa (Rocket salad) is known for its antiulcer properties in the traditional system of treatment. The present study was, therefore, designed to scrutinize its effect on urease activity in vitro. The results demonstrated marked attenuation of urease by the crude extract of various test concentrations with IC50 value of 7.77 mg/mL. On fractionation, marked change in inhibitory profile was observed. The ethyl acetate fraction was the most potent urease inhibitor with IC50 value of 4.17 mg/mL followed by the aqueous fraction with an IC50 value of 5.83 mg/mL. However, hexane did not show significant urease inhibition. In conclusion, the present study illustrated strong antagonism of urease activity and thus validated scientifically the traditional use of the plant in the treatment of ulcers.

  19. Enhancement of LPS-Induced Microglial Inflammation Response via TLR4 Under High Glucose Conditions

    Directory of Open Access Journals (Sweden)

    Xiang Zhang

    2015-03-01

    Full Text Available Background: Microglia activation mediated by toll-like receptor 4 (TLR4 plays an important role in neuroinflammation and postoperative cognitive dysfunction (POCD. Diabetes mellitus (DM has been recently suggested as an independent risk factor for POCD. In this study, we investigate the potential exacerbation of the inflammatory response in primary microglia due to high glucose conditions. Methods: Primary microglial cells were exposed to normal glucose (25 mmol/L and high glucose (35 mmol/L levels alone or with lipopolyscaccharide (LPS 0, 2, 5, 10 ng/mL. The pro-inflammatory response of the cells was assessed by measuring changes in cytokine levels and the evaluation of associated signaling pathways. Results: Neither high glucose nor low LPS (≤5ng/ml alone had an effect on TNF-a and IL-6 levels, but the combination of low LPS and high glucose stimulated the inflammatory response. Analyses of the associated signaling pathways demonstrated that high glucose enhanced the LPS-induced microglial activation via the TLR4/JAK2/STAT3 pathway. Conclusion: This study demonstrates that high glucose, one of the key abnormalities characteristic of DM, can augment LPS-induced microglial activation and inflammatory cytokine levels through the TLR4/JAK2/STAT3 pathway, offering new insight into the pathophysiological relationship between DM and POCD.

  20. Peroxisome proliferator-activated receptor-gamma agonist rosiglitazone attenuates postincisional pain by regulating macrophage polarization

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa-Moriyama, Maiko, E-mail: hase-mai@m3.kufm.kagoshima-u.ac.jp [Department of Anesthesiology and Critical Care Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan); Ohnou, Tetsuya; Godai, Kohei; Kurimoto, Tae; Nakama, Mayo; Kanmura, Yuichi [Department of Anesthesiology and Critical Care Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima 890-8520 (Japan)

    2012-09-14

    Highlights: Black-Right-Pointing-Pointer Rosiglitazone attenuated postincisional pain. Black-Right-Pointing-Pointer Rosiglitazone alters macrophage polarization to F4/80{sup +}CD206{sup +} M2 macrophages at the incisional sites. Black-Right-Pointing-Pointer Transplantation of rosiglitazone-treated macrophages produced analgesic effects. -- Abstract: Acute inflammation triggered by macrophage infiltration to injured tissue promotes wound repair and may induce pain hypersensitivity. Peroxisome proliferator-activated receptor {gamma} (PPAR){gamma} signaling is known to regulate heterogeneity of macrophages, which are often referred to as classically activated (M1) and alternatively activated (M2) macrophages. M1 macrophages have considerable antimicrobial activity and produce a wide variety of proinflammatory cytokines. In contrast, M2 macrophages are involved in anti-inflammatory and homeostatic functions linked to wound healing and tissue repair. Although it has been suggested that PPAR{gamma} agonists attenuate pain hypersensitivity, the molecular mechanism of macrophage-mediated effects of PPAR{gamma} signaling on pain development has not been explored. In this study, we investigated the link between the phenotype switching of macrophage polarization induced by PPAR{gamma} signaling and the development of acute pain hypersensitivity. Local administration of rosiglitazone significantly ameliorated hypersensitivity to heat and mechanical stimuli, and paw swelling. Consistent with the down-regulation of nuclear factor {kappa}B (NF{kappa}B) phosphorylation by rosiglitazone at the incisional sites, the number of F4/80{sup +}iNOS{sup +} M1 macrophages was decreased whereas numbers of F4/80{sup +}CD206{sup +} M2 macrophages were increased in rosiglitazone-treated incisional sites 24 h after the procedure. In addition, gene induction of anti-inflammatory M2-macrophage-associated markers such as arginase1, FIZZ1 and interleukin (IL)-10 were significantly increased, whereas

  1. Guggulsterone attenuates cerulein-induced acute pancreatitis via inhibition of ERK and JNK activation.

    Science.gov (United States)

    Kim, Dong-Goo; Bae, Gi-Sang; Choi, Sun-Bok; Jo, Il-Joo; Shin, Joon-Yeon; Lee, Sung-Kon; Kim, Myoung-Jin; Kim, Min-Jun; Jeong, Hyun-Woo; Choi, Chang-Min; Seo, Seung-Hee; Choo, Gab-Chul; Seo, Sang-Wan; Song, Ho-Joon; Park, Sung-Joo

    2015-05-01

    Guggulsterone (GS), a plant steroid and a compound found at high levels in Commiphora myrrha, exhibits anti-inflammatory, anti-cancer, and cholesterol-lowering effects. However, the potential of GS to ameliorate acute pancreatitis (AP) is unknown. The aim of this study was to evaluate the effects of GS on cerulein-induced AP. AP was induced by intraperitoneally injecting supramaximal concentrations of the stable cholecystokinin analog cerulein (50 μg/kg) hourly for 6 h. In the GS-treated group, GS was administered intraperitoneally (10, 25, or 50mg/kg) 1 h before the first cerulein injection. Mice were sacrificed 6 h after the final cerulein injection. Blood samples were collected to measure serum lipase levels and evaluate cytokine production. The pancreas and lung were rapidly removed for morphologic and histological examinations, flow cytometry analysis, myeloperoxidase (MPO) assay, and real-time reverse transcription-polymerase chain reaction analysis. Pre-treatment with GS attenuated cerulein-induced histological damage, reduced pancreas weight/body weight ratio, decreased serum lipase levels, inhibited infiltrations of macrophages and neutrophils, and suppressed cytokine production. Additionally, GS treatment suppressed the activation of extracellular signal-regulated protein kinase (ERK) and c-Jun N-terminal kinase (JNK) in the pancreas in cerulein-induced pancreatitis. In conclusion, our results suggest that GS attenuates AP via deactivation of ERK and JNK.

  2. Thermodynamics of tryptophan-mediated activation of the trp RNA-binding attenuation protein.

    Science.gov (United States)

    McElroy, Craig A; Manfredo, Amanda; Gollnick, Paul; Foster, Mark P

    2006-06-27

    The trp RNA-binding attenuation protein (TRAP) functions in many bacilli to control the expression of the tryptophan biosynthesis genes. Transcription of the trp operon is controlled by TRAP through an attenuation mechanism, in which competition between two alternative secondary-structural elements in the 5' leader sequence of the nascent mRNA is influenced by tryptophan-dependent binding of TRAP to the RNA. Previously, NMR studies of the undecamer (11-mer) suggested that tryptophan-dependent control of RNA binding by TRAP is accomplished through ligand-induced changes in protein dynamics. We now present further insights into this ligand-coupled event from hydrogen/deuterium (H/D) exchange analysis, differential scanning calorimetry (DSC), and isothermal titration calorimetry (ITC). Scanning calorimetry showed tryptophan dissociation to be independent of global protein unfolding, while analysis of the temperature dependence of the binding enthalpy by ITC revealed a negative heat capacity change larger than expected from surface burial, a hallmark of binding-coupled processes. Analysis of this excess heat capacity change using parameters derived from protein folding studies corresponds to the ordering of 17-24 residues per monomer of TRAP upon tryptophan binding. This result is in agreement with qualitative analysis of residue-specific broadening observed in TROSY NMR spectra of the 91 kDa oligomer. Implications for the mechanism of ligand-mediated TRAP activation through a shift in a preexisting conformational equilibrium and an induced-fit conformational change are discussed. PMID:16784236

  3. Activated protein C attenuates acute ischaemia reperfusion injury in skeletal muscle.

    LENUS (Irish Health Repository)

    Dillon, J P

    2012-02-03

    Activated protein C (APC) is an endogenous anti-coagulant with anti-inflammatory properties. The purpose of the present study was to evaluate the effects of activated protein C in the setting of skeletal muscle ischaemia reperfusion injury (IRI). IRI was induced in rats by applying rubber bands above the levels of the greater trochanters bilaterally for a period of 2h followed by 12h reperfusion. Treatment groups received either equal volumes of normal saline or activated protein C prior to tourniquet release. Following 12h reperfusion, muscle function was assessed electrophysiologically by electrical field stimulation. The animals were then sacrificed and skeletal muscle harvested for evaluation. Activated protein C significantly attenuated skeletal muscle reperfusion injury as shown by reduced myeloperoxidase content, wet to dry ratio and electrical properties of skeletal muscle. Further in vitro work was carried out on neutrophils isolated from healthy volunteers to determine the direct effect of APC on neutrophil function. The effects of APC on TNF-alpha stimulated neutrophils were examined by measuring CD18 expression as well as reactive oxygen species generation. The in vitro work demonstrated a reduction in CD18 expression and reactive oxygen species generation. We conclude that activated protein C may have a protective role in the setting of skeletal muscle ischaemia reperfusion injury and that this is in part mediated by a direct inhibitory effect on neutrophil activation.

  4. Salidroside Reduces Cell Mobility via NF-κB and MAPK Signaling in LPS-Induced BV2 Microglial Cells

    Directory of Open Access Journals (Sweden)

    Haixia Hu

    2014-01-01

    Full Text Available The unregulated activation of microglia following stroke results in the production of toxic factors that propagate secondary neuronal injury. Salidroside has been shown to exhibit protective effects against neuronal death induced by different insults. However, the molecular mechanisms responsible for the anti-inflammatory activity of salidroside have not been elucidated clearly in microglia. In the present study, we investigated the molecular mechanism underlying inhibiting LPS-stimulated BV2 microglial cell mobility of salidroside. The protective effect of salidroside was investigated in microglial BV2 cell, subjected to stretch injury. Moreover, transwell migration assay demonstrated that salidroside significantly reduced cell motility. Our results also indicated that salidroside suppressed LPS-induced chemokines production in a dose-dependent manner, without causing cytotoxicity in BV2 microglial cells. Moreover, salidroside suppressed LPS-induced activation of nuclear factor kappa B (NF-κB by blocking degradation of IκBα and phosphorylation of MAPK (p38, JNK, ERK1/2, which resulted in inhibition of chemokine expression. These results suggest that salidroside possesses a potent suppressive effect on cell migration of BV2 microglia and this compound may offer substantial therapeutic potential for treatment of ischemic strokes that are accompanied by microglial activation.

  5. Nonlinear disturbance attenuation control for four-leg active power filter based on voltage source inverter

    Institute of Scientific and Technical Information of China (English)

    Juming CHEN; Feng LIU; Shengwei MEI

    2006-01-01

    Active power filter (APF) based on voltage source inverter (VSI) is one of the important measures for handling the power quality problem. Mathematically, the APF model in a power grid is a typical nonlinear one. The idea of passivity is a powerful tool to study the stabilization of such a nonlinear system. In this paper, a state-space model of the four-leg APF is derived, based on which a new H-infinity controller for current tracking is proposed from the passivity point of view. It can achieve not only asymptotic tracking, but also disturbance attenuation in the sense of L2-gain. Subsequently,a sufficient condition to guarantee the boundedness and desired mean of the DC voltage is also given. This straightforward condition is consistent with the power-balancing law of electrical circuits. Simulations performed on PSCAD platform verify the validity of the new approach.

  6. Rapamycin attenuates mitochondrial dysfunction via activation of mitophagy in experimental ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Li, Qiang [Department of Neurology, Shanghai Sixth People’s Hospital, Shanghai Jiao Tong University, Shanghai 200233 (China); Department of Neurology, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011 (China); Zhang, Ting [Department of Neurology, Shanghai Sixth People’s Hospital, Shanghai Jiao Tong University, Shanghai 200233 (China); Wang, Jixian [Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025 (China); Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030 (China); Zhang, Zhijun [Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030 (China); Zhai, Yu [Department of Neurology, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011 (China); Yang, Guo-Yuan, E-mail: gyyang0626@gmail.com [Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025 (China); Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai 200030 (China); Sun, Xiaojiang, E-mail: sunxj19@gmail.com [Department of Neurology, Shanghai Sixth People’s Hospital, Shanghai Jiao Tong University, Shanghai 200233 (China)

    2014-02-07

    Highlights: • Rapamycin enhances mitophagy via increasing p62 translocation to the mitochondria. • Rapamycin attenuates brain ischemic damage and improves mitochondrial function. • The protection of rapamycin to mitochondrial is linked to enhanced mitophagy. - Abstract: Rapamycin has been demonstrated to exhibit neuroprotective functions via the activation of autophagy in a cerebral ischemia model. However, the involvement of mitophagy in this process and its contribution to the protection of mitochondrial function remains unknown. The present study explored the characteristics of mitophagy after cerebral ischemia and the effect of rapamycin on mitochondrial function. Male Sprague–Dawley rats underwent transient middle cerebral artery occlusion (tMCAO). Neurological deficits scores; infarct volumes; mitophagy morphology; and the levels of malondialdehyde (MDA), adenosine triphosphate (ATP) and mitochondrial membrane potentials (Δψm) were examined. The expression of LC3, Beclin-1 and p62 in the mitochondrial fraction combined with transmission electronic microscopy were used to explore mitophagic activity after ischemia. We also blocked autophagosome formation using 3-methyladenine (3-MA) to check the linkage between the mitochondrial protective effect of rapamycin and enhanced mitophagy. We observed that rapamycin significantly enhanced mitophagy, as evidenced by the increase in LC3-II and Beclin-1 expression in the mitochondria and p62 translocation to the mitochondria. Rapamycin reduced infarct volume, improved neurological outcomes and inhibited mitochondrial dysfunction compared with the control animals (p < 0.05). However, these protective effects were reversed by 3-methyladenine treatment after rapamycin. The present study indicates that rapamycin treatment attenuates mitochondrial dysfunction following cerebral ischemia, which is linked to enhanced mitophagy.

  7. Rapamycin attenuates mitochondrial dysfunction via activation of mitophagy in experimental ischemic stroke

    International Nuclear Information System (INIS)

    Highlights: • Rapamycin enhances mitophagy via increasing p62 translocation to the mitochondria. • Rapamycin attenuates brain ischemic damage and improves mitochondrial function. • The protection of rapamycin to mitochondrial is linked to enhanced mitophagy. - Abstract: Rapamycin has been demonstrated to exhibit neuroprotective functions via the activation of autophagy in a cerebral ischemia model. However, the involvement of mitophagy in this process and its contribution to the protection of mitochondrial function remains unknown. The present study explored the characteristics of mitophagy after cerebral ischemia and the effect of rapamycin on mitochondrial function. Male Sprague–Dawley rats underwent transient middle cerebral artery occlusion (tMCAO). Neurological deficits scores; infarct volumes; mitophagy morphology; and the levels of malondialdehyde (MDA), adenosine triphosphate (ATP) and mitochondrial membrane potentials (Δψm) were examined. The expression of LC3, Beclin-1 and p62 in the mitochondrial fraction combined with transmission electronic microscopy were used to explore mitophagic activity after ischemia. We also blocked autophagosome formation using 3-methyladenine (3-MA) to check the linkage between the mitochondrial protective effect of rapamycin and enhanced mitophagy. We observed that rapamycin significantly enhanced mitophagy, as evidenced by the increase in LC3-II and Beclin-1 expression in the mitochondria and p62 translocation to the mitochondria. Rapamycin reduced infarct volume, improved neurological outcomes and inhibited mitochondrial dysfunction compared with the control animals (p < 0.05). However, these protective effects were reversed by 3-methyladenine treatment after rapamycin. The present study indicates that rapamycin treatment attenuates mitochondrial dysfunction following cerebral ischemia, which is linked to enhanced mitophagy

  8. Ginsenoside Rg1 inhibiting the lipopolysaccharide-induced activation of microglial cells%三七皂苷Rg1抑制脂多糖诱导的小胶质细胞激活

    Institute of Scientific and Technical Information of China (English)

    宗一; 戴纪男; 孙俊; 杨萍; 张伟; 艾青龙; 陆地

    2012-01-01

    Objective To investigate whether ginsenoside Rgl ( Rgl ) inhibits the expression of potentially pro-inflammatory cytokines by cultured murine microglial BV-2 cells stimulated with lipopolysaccharide ( LPS ). Methods An inflammatory cell model was structured by LPS-stimulated microglial BV-2 cells. The inflammatory cells were treated with Rgl ( 10,20 and 40|xmol/L ) prior to LPS exposure. The effects on the mRNA and protein levels of pro-inflammatory enzymes, inducible nitric oxide synthase ( iNOS ), cyclooxygenase-2 ( COX-2 ), pro-inflammatory cytokines, tumor necrosis factor-ct ( TNF-ct ), interleukin-1 (3 ( IL-1 (3 ), and inflammatory signaling proteins nuclear factor-KB ( NF-kB ) were analysed by reverse transcription-polymerase chain reaction ( RT-PCR ) and immunofluorescence staining assay. The effects of Rgl on viability of BV-2 cells were measured by MTT assay. Results The results indicated that LPS-induced iNOS and COX-2 protein and mRNA expression levels decreased significantly by Rgl in a concentration-dependent manner. Rgl also had an effect on the expression of TNF-ct, IL-1 (3 and NF-kB through transcriptional and translational inhibition. In addition, Rgl dose-dependently decreased the increasing expression of iNOS, COX-2 and NF-kB protein and mRNA stimulated by LPS. Conclusion Rgl exerts anti-neuroinflammatory via regulating microglial BV-2 cells to release inflammatory factors.%目的 探讨三七皂苷Rg1(Rg1)对脂多糖(LPS)诱导的小胶质细胞系BV-2细胞炎性因子释放的抑制作用.方法 用LPS刺激BV-2细胞构建炎症模型,采用四甲基偶氮唑盐比色法检测Rg1对BV-2细胞活力的影响,免疫荧光染色和反转录PCR方法检测不同浓度Rg1(10、20、40μmol/L)对细胞炎性蛋白酶诱导型一氧化氮合酶(iNOS)和环氧合酶-2 (COX-2)、细胞炎性因子肿瘤坏死因子-α(TNF-α)和白细胞介素-1β(IL-1β)、炎性信号分子NF-κB蛋白与mRNA的表达变化.结果 不同浓度的Rg1在转录水平

  9. Invariant NKT Cell Activation Induces Late Preterm Birth That Is Attenuated by Rosiglitazone.

    Science.gov (United States)

    St Louis, Derek; Romero, Roberto; Plazyo, Olesya; Arenas-Hernandez, Marcia; Panaitescu, Bogdan; Xu, Yi; Milovic, Tatjana; Xu, Zhonghui; Bhatti, Gaurav; Mi, Qing-Sheng; Drewlo, Sascha; Tarca, Adi L; Hassan, Sonia S; Gomez-Lopez, Nardhy

    2016-02-01

    Preterm birth (PTB) is the leading cause of neonatal morbidity and mortality worldwide. Although intra-amniotic infection is a recognized cause of spontaneous preterm labor, the noninfection-related etiologies are poorly understood. In this article, we demonstrated that the expansion of activated CD1d-restricted invariant NKT (iNKT) cells in the third trimester by administration of α-galactosylceramide (α-GalCer) induced late PTB and neonatal mortality. In vivo imaging revealed that fetuses from mice that underwent α-GalCer-induced late PTB had bradycardia and died shortly after delivery. Yet, administration of α-GalCer in the second trimester did not cause pregnancy loss. Peroxisome proliferator-activated receptor (PPAR)γ activation, through rosiglitazone treatment, reduced the rate of α-GalCer-induced late PTB and improved neonatal survival. Administration of α-GalCer in the third trimester suppressed PPARγ activation, as shown by the downregulation of Fabp4 and Fatp4 in myometrial and decidual tissues, respectively; this suppression was rescued by rosiglitazone treatment. Administration of α-GalCer in the third trimester induced an increase in the activation of conventional CD4(+) T cells in myometrial tissues and the infiltration of activated macrophages, neutrophils, and mature dendritic cells to myometrial and/or decidual tissues. All of these effects were blunted after rosiglitazone treatment. Administration of α-GalCer also upregulated the expression of inflammatory genes at the maternal-fetal interface and systemically, and rosiglitazone treatment partially attenuated these responses. Finally, an increased infiltration of activated iNKT-like cells in human decidual tissues is associated with noninfection-related preterm labor/birth. Collectively, these results demonstrate that iNKT cell activation in vivo leads to late PTB by initiating innate and adaptive immune responses and suggest that the PPARγ pathway has potential as a target for

  10. Activation of farnesoid X receptor attenuates hepatic injury in a murine model of alcoholic liver disease.

    Science.gov (United States)

    Wu, Weibin; Zhu, Bo; Peng, Xiaomin; Zhou, Meiling; Jia, Dongwei; Gu, Jianxin

    2014-01-01

    Alcoholic liver disease (ALD) is a common cause of advanced liver disease, and considered as a major risk factor of morbidity and mortality worldwide. Hepatic cholestasis is a pathophysiological feature observed in all stages of ALD. The farnesoid X receptor (FXR) is a member of the nuclear hormone receptor superfamily, and plays an essential role in the regulation of bile acid, lipid and glucose homeostasis. However, the role of FXR in the pathogenesis and progression of ALD remains largely unknown. Mice were fed Lieber-DeCarli ethanol diet or an isocaloric control diet. We used a specific agonist of FXR WAY-362450 to study the effect of pharmacological activation of FXR in alcoholic liver disease. In this study, we demonstrated that FXR activity was impaired by chronic ethanol ingestion in a murine model of ALD. Activation of FXR by specific agonist WAY-362450 protected mice from the development of ALD. We also found that WAY-362450 treatment rescued FXR activity, suppressed ethanol-induced Cyp2e1 up-regulation and attenuated oxidative stress in liver. Our results highlight a key role of FXR in the modulation of ALD development, and propose specific FXR agonists for the treatment of ALD patients. PMID:24269813

  11. Inhibition of classical complement activation attenuates liver ischaemia and reperfusion injury in a rat model.

    Science.gov (United States)

    Heijnen, B H M; Straatsburg, I H; Padilla, N D; Van Mierlo, G J; Hack, C E; Van Gulik, T M

    2006-01-01

    Activation of the complement system contributes to the pathogenesis of ischaemia/reperfusion (I/R) injury. We evaluated inhibition of the classical pathway of complement using C1-inhibitor (C1-inh) in a model of 70% partial liver I/R injury in male Wistar rats (n = 35). C1-inh was administered at 100, 200 or 400 IU/kg bodyweight, 5 min before 60 min ischaemia (pre-I) or 5 min before 24 h reperfusion (end-I). One hundred IU/kg bodyweight significantly reduced the increase of plasma levels of activated C4 as compared to albumin-treated control rats and attenuated the increase of alanine aminotransferase (ALT). These effects were not better with higher doses of C1-inh. Administration of C1-inh pre-I resulted in lower ALT levels and higher bile secretion after 24 h of reperfusion than administration at end-I. Immunohistochemical assessment indicated that activated C3, the membrane attack complex C5b9 and C-reactive protein (CRP) colocalized in hepatocytes within midzonal areas, suggesting CRP is a mediator of I/R-induced, classical complement activation in rats. Pre-ischaemic administration of C1-inh is an effective pharmacological intervention to protect against liver I/R injury.

  12. A non canonical subtilase attenuates the transcriptional activation of defence responses in Arabidopsis thaliana

    Science.gov (United States)

    Serrano, Irene; Buscaill, Pierre; Audran, Corinne; Pouzet, Cécile; Jauneau, Alain; Rivas, Susana

    2016-01-01

    Proteases play crucial physiological functions in all organisms by controlling the lifetime of proteins. Here, we identified an atypical protease of the subtilase family [SBT5.2(b)] that attenuates the transcriptional activation of plant defence independently of its protease activity. The SBT5.2 gene produces two distinct transcripts encoding a canonical secreted subtilase [SBT5.2(a)] and an intracellular protein [SBT5.2(b)]. Concomitant to SBT5.2(a) downregulation, SBT5.2(b) expression is induced after bacterial inoculation. SBT5.2(b) localizes to endosomes where it interacts with and retains the defence-related transcription factor MYB30. Nuclear exclusion of MYB30 results in its reduced transcriptional activation and, thus, suppressed resistance. sbt5.2 mutants, with abolished SBT5.2(a) and SBT5.2(b) expression, display enhanced defence that is suppressed in a myb30 mutant background. Moreover, overexpression of SBT5.2(b), but not SBT5.2(a), in sbt5.2 plants reverts the phenotypes displayed by sbt5.2 mutants. Overall, we uncover a regulatory mode of the transcriptional activation of defence responses previously undescribed in eukaryotes. DOI: http://dx.doi.org/10.7554/eLife.19755.001 PMID:27685353

  13. Bioaccessible (poly)phenol metabolites from raspberry protect neural cells from oxidative stress and attenuate microglia activation.

    Science.gov (United States)

    Garcia, Gonçalo; Nanni, Sara; Figueira, Inês; Ivanov, Ines; McDougall, Gordon J; Stewart, Derek; Ferreira, Ricardo B; Pinto, Paula; Silva, Rui F M; Brites, Dora; Santos, Cláudia N

    2017-01-15

    Neuroinflammation is an integral part of the neurodegeneration process inherent to several aging dysfunctions. Within the central nervous system, microglia are the effective immune cells, responsible for neuroinflammatory responses. In this study, raspberries were subjected to in vitro digestion simulation to obtain the components that result from the gastrointestinal (GI) conditions, which would be bioaccessible and available for blood uptake. Both the original raspberry extract and the gastrointestinal bioaccessible (GIB) fraction protected neuronal and microglia cells against H2O2-induced oxidative stress and lipopolysaccharide (LPS)-induced inflammation, at low concentrations. Furthermore, this neuroprotective capacity was independent of intracellular ROS scavenging mechanisms. We show for the first time that raspberry metabolites present in the GIB fraction significantly inhibited microglial pro-inflammatory activation by LPS, through the inhibition of Iba1 expression, TNF-α release and NO production. Altogether, this study reveals that raspberry polyphenols may present a dietary route to the retardation or amelioration of neurodegenerative-related dysfunctions. PMID:27542476

  14. New compound, 5-O-isoferuloyl-2-deoxy-D-ribono-γ-lacton from Clematis mandshurica: Anti-inflammatory effects in lipopolysaccharide-stimulated BV2 microglial cells.

    Science.gov (United States)

    Dilshara, Matharage Gayani; Lee, Kyoung-Tae; Lee, Chang-Min; Choi, Yung Hyun; Lee, Hak-Ju; Choi, Il-Whan; Kim, Gi-Young

    2015-01-01

    Microglia are main immune cells to exacerbate neural disorders in persistent overactivating. Therefore, it is a good strategy to regulate microglia for the treatment of neural disorders. In the present study, we isolated and characterized a novel compound, 5-O-isoferuloyl-2-deoxy-D-ribono-γ-lacton (5-DRL) from Clematis mandshurica, and evaluated its anti-inflammatory effect in lipopolysaccharide (LPS)-treated BV2 microglial cells. 5-DRL inhibited the expression of LPS-stimulated proinflammatory mediators such as nitric oxide (NO) and prostaglandin E2 (PGE2), as well as their regulatory genes inducible NO syntheses (iNOS) and cyclooxygenase-2 (COX-2). 5-DRL also downregulated the LPS-induced DNA-binding activity of nuclear factor-κB (NF-κB) through suppression of the nuclear translocation of the NF-κB subunits, p65 and p50. Consistent with the inhibition of iNOS and COX-2 via NF-κB activity with 5-DRL, an inhibitor of NF-κB, pyrrolidine dithiocarbamate (PDTC), also led to the suppression of LPS-induced iNOS and COX-2 expression. Additionally, 5-DRL corresponding with antioxidants, N-acetylcysteine (NAC) and glutathione (GSH), remarkably inhibited reactive oxygen species (ROS) generation. Both NAC and GSH, thus attenuated the expression of iNOS and COX-2 by suppressing NF-κB activation, indicating that 5-DRL suppresses LPS-induced iNOS and COX-2 expression through downregulation of the ROS-dependent NF-κB signaling pathway. The present study also indicated that 5-DRL suppresses NO and PGE2 production by inducing heme oxygenase-1 (HO-1) via nuclear factor erythroid 2-related factor 2 (Nrf2). Taken together, the present data indicate that 5-DRL attenuates the production of proinflammatory mediators such as NO and PGE2 as well as their regulatory genes in LPS-stimulated BV2 microglial cells by inhibiting ROS-dependent NF-κB activation and stimulating the Nrf2/HO-1 signal pathway. These data may be implicated in the application of 5-DRL in LPS

  15. Entry and distribution of microglial cells in human embryonic and fetal cerebral cortex.

    Science.gov (United States)

    Monier, Anne; Adle-Biassette, Homa; Delezoide, Anne-Lise; Evrard, Philippe; Gressens, Pierre; Verney, Catherine

    2007-05-01

    Microglial cells penetrate into and scatter throughout the human cortical grey and white matter according to a specific spatiotemporal pattern during the first 2 trimesters of gestation. Routes of entry were quantitatively and qualitatively different from those identified in the diencephalon. Starting at 4.5 gestational weeks, amoeboid microglial cells, characterized by different antibodies as Iba1, CD68, CD45, and MHC-II, entered the cerebral wall from the ventricular lumen and the leptomeninges. Migration was mainly radial and tangential toward the immature white matter, subplate layer, and cortical plate, whereas pial cells populated the prospective layer I. The intraparenchymal vascular route of entry was detectable only from 12 gestational weeks. Interestingly, microglial cells accumulated in restricted laminar bands particularly at 19 to 24 gestational weeks among the corona radiata fibers rostrally, extending caudally in the immature white matter to reach the visual radiations. This accumulation of proliferating MIB1-positive microglia (as shown by MIB1-Iba1 double immunolabeling) was located at the site of white matter injury in premature neonates. The spatiotemporal organization of microglia in the immature white and grey matter suggests that these cells may play active roles in developmental processes and in injury to the developing brain. PMID:17483694

  16. Music Attenuated a Decrease in Parasympathetic Nervous System Activity after Exercise.

    Directory of Open Access Journals (Sweden)

    Tiantian Jia

    Full Text Available Music and exercise can both affect autonomic nervous system activity. However, the effects of the combination of music and exercise on autonomic activity are poorly understood. Additionally, it remains unknown whether music affects post-exercise orthostatic tolerance. The aim of this study was to evaluate the effects of music on autonomic nervous system activity in orthostatic tolerance after exercise. Twenty-six healthy graduate students participated in four sessions in a random order on four separate days: a sedentary session, a music session, a bicycling session, and a bicycling with music session. Participants were asked to listen to their favorite music and to exercise on a cycle ergometer. We evaluated autonomic nervous system activity before and after each session using frequency analysis of heart rate variability. High frequency power, an index of parasympathetic nervous system activity, was significantly increased in the music session. Heart rate was increased, and high frequency power was decreased, in the bicycling session. There was no significant difference in high frequency power before and after the bicycling with music session, although heart rate was significantly increased. Additionally, both music and exercise did not significantly affect heart rate, systolic blood pressure or also heart rate variability indices in the orthostatic test. These data suggest that music increased parasympathetic activity and attenuated the exercise-induced decrease in parasympathetic activity without altering the orthostatic tolerance after exercise. Therefore, music may be an effective approach for improving post-exercise parasympathetic reactivation, resulting in a faster recovery and a reduction in cardiac stress after exercise.

  17. Music Attenuated a Decrease in Parasympathetic Nervous System Activity after Exercise.

    Science.gov (United States)

    Jia, Tiantian; Ogawa, Yoshiko; Miura, Misa; Ito, Osamu; Kohzuki, Masahiro

    2016-01-01

    Music and exercise can both affect autonomic nervous system activity. However, the effects of the combination of music and exercise on autonomic activity are poorly understood. Additionally, it remains unknown whether music affects post-exercise orthostatic tolerance. The aim of this study was to evaluate the effects of music on autonomic nervous system activity in orthostatic tolerance after exercise. Twenty-six healthy graduate students participated in four sessions in a random order on four separate days: a sedentary session, a music session, a bicycling session, and a bicycling with music session. Participants were asked to listen to their favorite music and to exercise on a cycle ergometer. We evaluated autonomic nervous system activity before and after each session using frequency analysis of heart rate variability. High frequency power, an index of parasympathetic nervous system activity, was significantly increased in the music session. Heart rate was increased, and high frequency power was decreased, in the bicycling session. There was no significant difference in high frequency power before and after the bicycling with music session, although heart rate was significantly increased. Additionally, both music and exercise did not significantly affect heart rate, systolic blood pressure or also heart rate variability indices in the orthostatic test. These data suggest that music increased parasympathetic activity and attenuated the exercise-induced decrease in parasympathetic activity without altering the orthostatic tolerance after exercise. Therefore, music may be an effective approach for improving post-exercise parasympathetic reactivation, resulting in a faster recovery and a reduction in cardiac stress after exercise. PMID:26840532

  18. Music Attenuated a Decrease in Parasympathetic Nervous System Activity after Exercise.

    Science.gov (United States)

    Jia, Tiantian; Ogawa, Yoshiko; Miura, Misa; Ito, Osamu; Kohzuki, Masahiro

    2016-01-01

    Music and exercise can both affect autonomic nervous system activity. However, the effects of the combination of music and exercise on autonomic activity are poorly understood. Additionally, it remains unknown whether music affects post-exercise orthostatic tolerance. The aim of this study was to evaluate the effects of music on autonomic nervous system activity in orthostatic tolerance after exercise. Twenty-six healthy graduate students participated in four sessions in a random order on four separate days: a sedentary session, a music session, a bicycling session, and a bicycling with music session. Participants were asked to listen to their favorite music and to exercise on a cycle ergometer. We evaluated autonomic nervous system activity before and after each session using frequency analysis of heart rate variability. High frequency power, an index of parasympathetic nervous system activity, was significantly increased in the music session. Heart rate was increased, and high frequency power was decreased, in the bicycling session. There was no significant difference in high frequency power before and after the bicycling with music session, although heart rate was significantly increased. Additionally, both music and exercise did not significantly affect heart rate, systolic blood pressure or also heart rate variability indices in the orthostatic test. These data suggest that music increased parasympathetic activity and attenuated the exercise-induced decrease in parasympathetic activity without altering the orthostatic tolerance after exercise. Therefore, music may be an effective approach for improving post-exercise parasympathetic reactivation, resulting in a faster recovery and a reduction in cardiac stress after exercise.

  19. Music Attenuated a Decrease in Parasympathetic Nervous System Activity after Exercise

    Science.gov (United States)

    Miura, Misa; Ito, Osamu; Kohzuki, Masahiro

    2016-01-01

    Music and exercise can both affect autonomic nervous system activity. However, the effects of the combination of music and exercise on autonomic activity are poorly understood. Additionally, it remains unknown whether music affects post-exercise orthostatic tolerance. The aim of this study was to evaluate the effects of music on autonomic nervous system activity in orthostatic tolerance after exercise. Twenty-six healthy graduate students participated in four sessions in a random order on four separate days: a sedentary session, a music session, a bicycling session, and a bicycling with music session. Participants were asked to listen to their favorite music and to exercise on a cycle ergometer. We evaluated autonomic nervous system activity before and after each session using frequency analysis of heart rate variability. High frequency power, an index of parasympathetic nervous system activity, was significantly increased in the music session. Heart rate was increased, and high frequency power was decreased, in the bicycling session. There was no significant difference in high frequency power before and after the bicycling with music session, although heart rate was significantly increased. Additionally, both music and exercise did not significantly affect heart rate, systolic blood pressure or also heart rate variability indices in the orthostatic test. These data suggest that music increased parasympathetic activity and attenuated the exercise-induced decrease in parasympathetic activity without altering the orthostatic tolerance after exercise. Therefore, music may be an effective approach for improving post-exercise parasympathetic reactivation, resulting in a faster recovery and a reduction in cardiac stress after exercise. PMID:26840532

  20. PERK Activation Promotes Medulloblastoma Tumorigenesis by Attenuating Premalignant Granule Cell Precursor Apoptosis.

    Science.gov (United States)

    Ho, Yeung; Li, Xiting; Jamison, Stephanie; Harding, Heather P; McKinnon, Peter J; Ron, David; Lin, Wensheng

    2016-07-01

    Evidence suggests that activation of pancreatic endoplasmic reticulum kinase (PERK) signaling in response to endoplasmic reticulum stress negatively or positively influences cell transformation by regulating apoptosis. Patched1 heterozygous deficient (Ptch1(+/-)) mice reproduce human Gorlin's syndrome and are regarded as the best animal model to study tumorigenesis of the sonic hedgehog subgroup of medulloblastomas. It is believed that medulloblastomas in Ptch1(+/-) mice results from the transformation of granule cell precursors (GCPs) in the developing cerebellum. Here, we determined the role of PERK signaling on medulloblastoma tumorigenesis by assessing its effects on premalignant GCPs and tumor cells. We found that PERK signaling was activated in both premalignant GCPs in young Ptch1(+/-) mice and medulloblastoma cells in adult mice. We demonstrated that PERK haploinsufficiency reduced the incidence of medulloblastomas in Ptch1(+/-) mice. Interestingly, PERK haploinsufficiency enhanced apoptosis of premalignant GCPs in young Ptch1(+/-) mice but had no significant effect on medulloblastoma cells in adult mice. Moreover, we showed that the PERK pathway was activated in medulloblastomas in humans. These results suggest that PERK signaling promotes medulloblastoma tumorigenesis by attenuating apoptosis of premalignant GCPs during the course of malignant transformation. PMID:27181404

  1. Amiloride lowers blood pressure and attenuates urine plasminogen activation in patients with treatment-resistant hypertension.

    Science.gov (United States)

    Oxlund, Christina S; Buhl, Kristian B; Jacobsen, Ib A; Hansen, Mie R; Gram, Jeppe; Henriksen, Jan Erik; Schousboe, Karoline; Tarnow, Lise; Jensen, Boye L

    2014-12-01

    In conditions with albuminuria, plasminogen is aberrantly filtered across the glomerular barrier and activated along the tubular system to plasmin. In the collecting duct, plasmin activates epithelial sodium channels (ENaC) proteolytically. Hyperactivity of ENaC could link microalbuminuria/proteinuria to resistant hypertension. Amiloride, an ENaC inhibitor, inhibits urokinase-type plasminogen activator. We hypothesized that amiloride (1) reduces blood pressure (BP); (2) attenuates plasminogen-to-plasmin activation; and (3) inhibits urine urokinase-type plasminogen activator in patients with resistant hypertension and type 2 diabetes mellitus (T2DM).In an open-label, non-randomized, 8-week intervention study, a cohort (n = 80) of patients with resistant hypertension and T2DM were included. Amiloride (5 mg/d) was added to previous triple antihypertensive treatment (including a diuretic and an inhibitor of the renin-angiotensin-aldosterone system) and increased to 10 mg if BP control was not achieved at 4 weeks. Complete dataset for urine analysis was available in 60 patients. Systolic and diastolic BP measured by ambulatory BP monitoring and office monitoring were significantly reduced. Average daytime BP was reduced by 6.3/3.0 mm Hg. Seven of 80 cases (9%) discontinued amiloride due to hyperkalemia >5.5 mol/L, the most frequent adverse event. Urinary plasmin(ogen) and albumin excretions were significantly reduced after amiloride treatment (P treatment. Amiloride lowers BP, urine plasminogen excretion and activation, and albumin/creatinine ratio, and is a relevant add-on medication for the treatment of resistant hypertension in patients with T2DM and microalbuminuria.

  2. Repetitive cryotherapy attenuates the in vitro and in vivo mononuclear cell activation response.

    Science.gov (United States)

    Lindsay, Angus; Othman, Mohd Izani; Prebble, Hannah; Davies, Sian; Gieseg, Steven P

    2016-07-01

    What is the central question of this study? Acute and repetitive cryotherapy are routinely used to accelerate postexercise recovery, although the effect on resident immune cells and repetitive exposure has largely been unexplored and neglected. What is the main finding and its importance? Using blood-derived mononuclear cells and semi-professional mixed martial artists, we show that acute and repetitive cryotherapy reduces the in vitro and in vivo T-cell and monocyte activation response whilst remaining independent of the physical performance of elite athletes. We investigated the effect of repetitive cryotherapy on the in vitro (cold exposure) and in vivo (cold water immersion) activation of blood-derived mononuclear cells following high-intensity exercise. Single and repeated cold exposure (5°C) of a mixed cell culture (T cells and monocytes) was investigated using in vitro tissue culture experimentation for total neopterin production (neopterin plus 7,8-dihydroneopterin). Fourteen elite mixed martial art fighters were also randomly assigned to either a cold water immersion (15 min at 10°C) or passive recovery protocol, which they completed three times per week during a 6 week training camp. Urine was collected and analysed for neopterin and total neopterin three times per week, and perceived soreness, fatigue, physical performance (broad jump, push-ups and pull-ups) and training performance were also assessed. Single and repetitive cold exposure significantly (P < 0.001) reduced total neopterin production from the mixed cell culture, whereas cold water immersion significantly (P < 0.05) attenuated urinary neopterin and total neopterin during the training camp without having any effect on physical performance parameters. Soreness and fatigue showed little variation between the groups, whereas training session performance was significantly (P < 0.05) elevated in the cold water immersion group. The data suggest that acute and repetitive cryotherapy

  3. Carboxylic Acid Fullerene (C60) Derivatives Attenuated Neuroinflammatory Responses by Modulating Mitochondrial Dynamics

    Science.gov (United States)

    Ye, Shefang; Zhou, Tong; Cheng, Keman; Chen, Mingliang; Wang, Yange; Jiang, Yuanqin; Yang, Peiyan

    2015-05-01

    Fullerene (C60) derivatives, a unique class of compounds with potent antioxidant properties, have been reported to exert a wide variety of biological activities including neuroprotective properties. Mitochondrial dynamics are an important constituent of cellular quality control and function, and an imbalance of the dynamics eventually leads to mitochondria disruption and cell dysfunctions. This study aimed to assess the effects of carboxylic acid C60 derivatives (C60-COOH) on mitochondrial dynamics and elucidate its associated mechanisms in lipopolysaccharide (LPS)-stimulated BV-2 microglial cell model. Using a cell-based functional screening system labeled with DsRed2-mito in BV-2 cells, we showed that LPS stimulation led to excessive mitochondrial fission, increased mitochondrial localization of dynamin-related protein 1 (Drp1), both of which were markedly suppressed by C60-COOH pretreatment. LPS-induced mitochondria reactive oxygen species (ROS) generation and collapse of mitochondrial membrane potential (Δ Ψm) were also significantly inhibited by C60-COOH. Moreover, we also found that C60-COOH pretreatment resulted in the attenuation of LPS-mediated activation of nuclear factor (NF)-κB and mitogen-activated protein kinase (MAPK) signaling, as well as the production of pro-inflammatory mediators. Taken together, these findings demonstrated that carboxylic acid C60 derivatives may exert neuroprotective effects through regulating mitochondrial dynamics and functions in microglial cells, thus providing novel insights into the mechanisms of the neuroprotective properties of carboxylic acid C60 derivatives.

  4. Evidence of magma activation beneath the Lunayyir basaltic field (Saudi Arabia from attenuation tomography

    Directory of Open Access Journals (Sweden)

    I. Koulakov

    2014-06-01

    Full Text Available We present a seismic attenuation model for the crust beneath the Cenozoic basaltic field of Lunayyir (western Saudi Arabia, where a strong seismic swarm occurred in 2009. The tomography inversion uses the envelope shape of the S wave seismograms from over 300 strong events (M > 3.5. The resulting attenuation structures appear to be consistent with the distribution of seismic velocities. The obtained 3-D attenuation model distinguishes the low-attenuation zones down to 5 km depth corresponding to the rigid basaltic cover. At greater depths, we detect a high-attenuation anomaly coinciding with the main seismicity cluster. We propose that this zone corresponds to the upper part of the conduit area ascending from deeper magma sources. According to the distributions of local events, fluids and melts from this conduit appear to reach a depth of ~2 km, but were not able to reach the surface and cause the eruption in 2009.

  5. Molecular hydrogen attenuates hypoxia/reoxygenation injury of intrahepatic cholangiocytes by activating Nrf2 expression.

    Science.gov (United States)

    Yu, Jianhua; Zhang, Weiguang; Zhang, Rongguo; Jiang, Guixing; Tang, Haijun; Ruan, Xinxian; Ren, Peitu; Lu, Baochun

    2015-11-01

    Hypoxia/reoxygenation (H/R) injury of cholangiocytes causes serious biliary complications during hepatobiliary surgeries. Molecular hydrogen (H2) has been shown to be effective in protecting various cells and organs against oxidative stress injury. Human liver cholangiocytes were used to determine the potential protective effects of hydrogen against cholangiocyte H/R injury and explore the underlying mechanisms. We found that H2 ameliorated H/R-induced cholangiocytes apoptosis. Our study revealed that H2 activated NF-E2-related factor 2 (Nrf2) and downstream cytoprotective protein expression. However, the protective function of H2 was abolished when Nrf2 was silenced. Apoptosis in cholangiocytes isolated from a rat model of liver ischemia/reperfusion injury indicated that H2 significantly attenuates ischemia/reperfusion cholangiocyte injury in vivo. In conclusion, our study shows that H2 protects intrahepatic cholangiocytes from hypoxia/reoxygenation-induced apoptosis in vitro or in vivo, and this phenomenon may depend on activating Nrf2 expression.

  6. Loss of CARD9-mediated innate activation attenuates severe influenza pneumonia without compromising host viral immunity.

    Science.gov (United States)

    Uematsu, Takayuki; Iizasa, Ei'ichi; Kobayashi, Noritada; Yoshida, Hiroki; Hara, Hiromitsu

    2015-01-01

    Influenza virus (IFV) infection is a common cause of severe viral pneumonia associated with acute respiratory distress syndrome (ARDS), which is difficult to control with general immunosuppressive therapy including corticosteroids due to the unfavorable effect on viral replication. Studies have suggested that the excessive activation of the innate immunity by IFV is responsible for severe pathologies. In this study, we focused on CARD9, a signaling adaptor known to regulate innate immune activation through multiple innate sensor proteins, and investigated its role in anti-IFV defense and lung pathogenesis in a mouse model recapitulating severe influenza pneumonia with ARDS. We found that influenza pneumonia was dramatically attenuated in Card9-deficient mice, which showed improved mortality with reduced inflammatory cytokines and chemokines in the infected lungs. However, viral clearance, type-I interferon production, and the development of anti-viral B and T cell immunity were not compromised by CARD9 deficiency. Syk or CARD9-deficient DCs but not macrophages showed impaired cytokine but not type-I interferon production in response to IFV in vitro, indicating a possible role for the Syk-CARD9 pathway in DCs in excessive inflammation of IFV-infected lungs. Therefore, inhibition of this pathway is an ideal therapeutic target for severe influenza pneumonia without affecting viral clearance. PMID:26627732

  7. Endogenous n-3 Polyunsaturated Fatty Acids Attenuate T Cell-Mediated Hepatitis via Autophagy Activation

    Science.gov (United States)

    Li, Yanli; Tang, Yuan; Wang, Shoujie; Zhou, Jing; Zhou, Jia; Lu, Xiao; Bai, Xiaochun; Wang, Xiang-Yang; Chen, Zhengliang; Zuo, Daming

    2016-01-01

    Omega-3 polyunsaturated fatty acids (n-3 PUFAs) exert anti-inflammatory effects in several liver disorders, including cirrhosis, acute liver failure, and fatty liver disease. To date, little is known about their role in immune-mediated liver diseases. In this study, we used fat-1 transgenic mice rich in endogenous n-3 PUFAs to examine the role of n-3 PUFAs in immune-mediated liver injury. Concanavalin A (Con A) was administered intravenously to wild-type (WT) and fat-1 transgenic mice to induce T cell-mediated hepatitis. Reduced liver damage was shown in Con A-administrated fat-1 transgenic mice, as evidenced by decreased mortality, attenuated hepatic necrosis, lessened serum alanine aminotransferase activity, and inhibited production of pro-inflammatory cytokines (e.g., TNF-α, IL-6, IL-17A, and IFN-γ). In vivo and in vitro studies demonstrated that n-3 PUFAs significantly inhibited the activation of hepatic T cells and the differentiation of Th1 cells after Con A challenge. Further studies showed that n-3 PUFAs markedly increased autophagy level in Con A-treated fat-1 T cells compared with the WT counterparts. Blocking hepatic autophagy activity with chloroquine diminished the differences in T cell activation and liver injury between Con A-injected WT and fat-1 transgenic mice. We conclude that n-3 PUFAs limit Con A-induced hepatitis via an autophagy-dependent mechanism and could be exploited as a new therapeutic approach for autoimmune hepatitis. PMID:27679638

  8. Notch activation by phenethyl isothiocyanate attenuates its inhibitory effect on prostate cancer cell migration.

    Directory of Open Access Journals (Sweden)

    Su-Hyeong Kim

    Full Text Available Phenethyl isothiocyanate (PEITC is a promising cancer chemopreventive component of edible cruciferous vegetables with in vivo efficacy against prostate cancer in experimental rodents. Cancer chemopreventive response to PEITC is characterized by its ability to inhibit multiple oncogenic signaling pathways, including nuclear factor-κB, Akt, and androgen receptor. The present study demonstrates, for the first time, that PEITC treatment activates Notch signaling in malignant as well as normal human prostate cells. Exposure of human prostate cancer cells (LNCaP, PC-3, and DU145 and a normal human prostate epithelial cell line (PrEC to PEITC resulted in cleavage (active form of Notch1 and Notch2, and increased transcriptional activity of Notch. In PC-3 and LNCaP cells, PEITC treatment caused induction of Notch ligands Jagged1 and Jagged2 (PC-3, overexpression of γ-secretase complex components Presenilin1 and Nicastrin (PC-3, nuclear enrichment of cleaved Notch2, and/or up-regulation of Notch1, Notch2, Jagged1, and/or Jagged2 mRNA. PEITC-induced apoptosis in LNCaP and PC-3 cells was significantly attenuated by RNA interference of Notch2, but not by pharmacological inhibition of Notch1. Inhibition of PC-3 and LNCaP cell migration resulting from PEITC exposure was significantly augmented by knockdown of Notch2 protein as well as pharmacological inhibition of Notch1 activation. Nuclear expression of cleaved Notch2 protein was significantly higher in PC-3 xenografts from PEITC-treated mice and dorsolateral prostates from PEITC-fed TRAMP mice compared with respective control. Because Notch signaling is implicated in epithelial-mesenchymal transition and metastasis, the present study suggests that anti-metastatic effect of PEITC may be augmented by a combination regimen involving a Notch inhibitor.

  9. Attenuated food anticipatory activity and abnormal circadian locomotor rhythms in Rgs16 knockdown mice.

    Directory of Open Access Journals (Sweden)

    Naoto Hayasaka

    Full Text Available Regulators of G protein signaling (RGS are a multi-functional protein family, which functions in part as GTPase-activating proteins (GAPs of G protein α-subunits to terminate G protein signaling. Previous studies have demonstrated that the Rgs16 transcripts exhibit robust circadian rhythms both in the suprachiasmatic nucleus (SCN, the master circadian light-entrainable oscillator (LEO of the hypothalamus, and in the liver. To investigate the role of RGS16 in the circadian clock in vivo, we generated two independent transgenic mouse lines using lentiviral vectors expressing short hairpin RNA (shRNA targeting the Rgs16 mRNA. The knockdown mice demonstrated significantly shorter free-running period of locomotor activity rhythms and reduced total activity as compared to the wild-type siblings. In addition, when feeding was restricted during the daytime, food-entrainable oscillator (FEO-driven elevated food-anticipatory activity (FAA observed prior to the scheduled feeding time was significantly attenuated in the knockdown mice. Whereas the restricted feeding phase-advanced the rhythmic expression of the Per2 clock gene in liver and thalamus in the wild-type animals, the above phase shift was not observed in the knockdown mice. This is the first in vivo demonstration that a common regulator of G protein signaling is involved in the two separate, but interactive circadian timing systems, LEO and FEO. The present study also suggests that liver and/or thalamus regulate the food-entrained circadian behavior through G protein-mediated signal transduction pathway(s.

  10. Potential chemoprevention of LPS-stimulated nitric oxide and prostaglandin E₂ production by α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranosyl-3-indolecarbonate in BV2 microglial cells through suppression of the ROS/PI3K/Akt/NF-κB pathway.

    Science.gov (United States)

    Dilshara, Matharage Gayani; Lee, Kyoung-Tae; Choi, Yung Hyun; Moon, Dong-Oh; Lee, Hak-Ju; Yun, Sung Gyu; Kim, Gi-Young

    2014-02-01

    α-l-Rhamnopyranosyl-(1→6)-β-d-glucopyranosyl-3-indolecarbonate (RG3I) is a chemical constituent isolated from the commonly used Asian traditional medicinal plant, Clematis mandshurica; however, no studies have been reported on its anti-inflammatory properties. In the present study, we found that RG3I attenuates the lipopolysaccharide (LPS)-induced DNA-binding activity of nuclear factor-κB (NF-κB) via the dephosphorylation of PI3K/Akt in BV2 microglial cells, leading to a suppression of nitric oxide (NO) and prostaglandin E2 (PGE2) production, along with that of their regulatory genes, inducible NO synthase (iNOS) and cyclooxygenase-2 (Cox-2). Further, the PI3K/Akt inhibitor, LY294002 diminished the expression of LPS-stimulated iNOS and COX-2 genes by suppressing NF-κB activity. Moreover, RG3I significantly inhibited LPS-induced reactive oxygen species (ROS) generation similar to the ROS inhibitors, N-acetylcysteine (NAC) and glutathione (GSH). Notably, NAC and GSH abolished the LPS-induced expression of iNOS and Cox-2 in BV2 microglial cells by inhibiting NF-κB activity. Taken together, our data indicate that RG3I suppresses the production of proinflammatory mediators such as NO and PGE2 as well as their regulatory genes in LPS-stimulated BV2 microglial cells by inhibiting the PI3K/Akt- and ROS-dependent NF-κB signaling pathway, suggesting that RG3I may be a good candidate to regulate LPS-induced inflammatory response. PMID:24486459

  11. Early correlation of microglial activation with enhanced tumor necrosis factor-alpha and monocyte chemoattractant protein-1 expression specifically within the entorhinal cortex of triple transgenic Alzheimer's disease mice

    Directory of Open Access Journals (Sweden)

    LaFerla Frank M

    2005-10-01

    Full Text Available Abstract Background Alzheimer's disease is a complex neurodegenerative disorder characterized pathologically by a temporal and spatial progression of beta-amyloid (Aβ deposition, neurofibrillary tangle formation, and synaptic degeneration. Inflammatory processes have been implicated in initiating and/or propagating AD-associated pathology within the brain, as inflammatory cytokine expression and other markers of inflammation are pronounced in individuals with AD pathology. The current study examines whether inflammatory processes are evident early in the disease process in the 3xTg-AD mouse model and if regional differences in inflammatory profiles exist. Methods Coronal brain sections were used to identify Aβ in 2, 3, and 6-month 3xTg-AD and non-transgenic control mice. Quantitative real-time RT-PCR was performed on microdissected entorhinal cortex and hippocampus tissue of 2, 3, and 6-month 3xTg-AD and non-transgenic mice. Microglial/macrophage cell numbers were quantified using unbiased stereology in 3xTg-AD and non-transgenic entorhinal cortex and hippocampus containing sections. Results We observed human Aβ deposition at 3 months in 3xTg-AD mice which is enhanced by 6 months of age. Interestingly, we observed a 14.8-fold up-regulation of TNF-α and 10.8-fold up-regulation of MCP-1 in the entorhinal cortex of 3xTg-AD mice but no change was detected over time in the hippocampus or in either region of non-transgenic mice. Additionally, this increase correlated with a specific increase in F4/80-positive microglia and macrophages in 3xTg-AD entorhinal cortex. Conclusion Our data provide evidence for early induction of inflammatory processes in a model that develops amyloid and neurofibrillary tangle pathology. Additionally, our results link inflammatory processes within the entorhinal cortex, which represents one of the earliest AD-affected brain regions.

  12. Repetitive cryotherapy attenuates the in vitro and in vivo mononuclear cell activation response.

    Science.gov (United States)

    Lindsay, Angus; Othman, Mohd Izani; Prebble, Hannah; Davies, Sian; Gieseg, Steven P

    2016-07-01

    What is the central question of this study? Acute and repetitive cryotherapy are routinely used to accelerate postexercise recovery, although the effect on resident immune cells and repetitive exposure has largely been unexplored and neglected. What is the main finding and its importance? Using blood-derived mononuclear cells and semi-professional mixed martial artists, we show that acute and repetitive cryotherapy reduces the in vitro and in vivo T-cell and monocyte activation response whilst remaining independent of the physical performance of elite athletes. We investigated the effect of repetitive cryotherapy on the in vitro (cold exposure) and in vivo (cold water immersion) activation of blood-derived mononuclear cells following high-intensity exercise. Single and repeated cold exposure (5°C) of a mixed cell culture (T cells and monocytes) was investigated using in vitro tissue culture experimentation for total neopterin production (neopterin plus 7,8-dihydroneopterin). Fourteen elite mixed martial art fighters were also randomly assigned to either a cold water immersion (15 min at 10°C) or passive recovery protocol, which they completed three times per week during a 6 week training camp. Urine was collected and analysed for neopterin and total neopterin three times per week, and perceived soreness, fatigue, physical performance (broad jump, push-ups and pull-ups) and training performance were also assessed. Single and repetitive cold exposure significantly (P mixed cell culture, whereas cold water immersion significantly (P groups, whereas training session performance was significantly (P group. The data suggest that acute and repetitive cryotherapy attenuates in vitro T-cell and monocyte activation. This may explain the disparity in in vivo neopterin and total neopterin between cold water immersion and passive recovery following repetitive exposure during a high-intensity physical impact sport that remains independent of physical performance. PMID

  13. Activation of AMP-activated protein kinase attenuates hepatocellular carcinoma cell adhesion stimulated by adipokine resistin

    OpenAIRE

    Yang, Chen-Chieh; Chang, Shun-Fu; Chao, Jian-Kang; Lai, Yi-Liang; Chang, Wei-En; Hsu, Wen-Hsiu; Kuo, Wu-Hsien

    2014-01-01

    Background Resistin, adipocyte-secreting adipokine, may play critical role in modulating cancer pathogenesis. The aim of this study was to investigate the effects of resistin on HCC adhesion to the endothelium, and the mechanism underlying these resistin effects. Methods Human SK-Hep1 cells were used to study the effect of resistin on intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) expressions as well as NF-κB activation, and hence cell adhesion to hu...

  14. [Microglial cells and development of the embryonic central nervous system].

    Science.gov (United States)

    Legendre, Pascal; Le Corronc, Hervé

    2014-02-01

    Microglia cells are the macrophages of the central nervous system with a crucial function in the homeostasis of the adult brain. However, recent studies showed that microglial cells may also have important functions during early embryonic central nervous system development. In this review we summarize recent works on the extra embryonic origin of microglia, their progenitor niche, the pattern of their invasion of the embryonic central nervous system and on interactions between embryonic microglia and their local environment during invasion. We describe microglial functions during development of embryonic neuronal networks, including their roles in neurogenesis, in angiogenesis and developmental cell death. These recent discoveries open a new field of research on the functions of neural-microglial interactions during the development of the embryonic central nervous system.

  15. Estimation of absolute microglial cell numbers in mouse fascia dentata using unbiased and efficient stereological cell counting principles.

    Science.gov (United States)

    Wirenfeldt, Martin; Dalmau, Ishar; Finsen, Bente

    2003-11-01

    Stereology offers a set of unbiased principles to obtain precise estimates of total cell numbers in a defined region. In terms of microglia, which in the traumatized and diseased CNS is an extremely dynamic cell population, the strength of stereology is that the resultant estimate is unaffected by shrinkage or expansion of the tissue. The optical fractionator technique is very efficient but requires relatively thick sections (e.g., > or =20 microm after coverslipping) and the unequivocal identification of labeled cells throughout the section thickness. We have adapted our protocol for Mac-1 immunohistochemical visualization of microglial cells in thick (70 microm) vibratome sections for stereological counting within the murine hippocampus, and we have compared the staining results with other selective microglial markers: the histochemical demonstration of nucleotide diphosphatase (NDPase) activity and the tomato lectin histochemistry. The protocol gives sections of high quality with a final mean section thickness of >20 microm (h=22.3 microm +/- 0.64 microm), and with excellent rendition of Mac-1+ microglia through the entire height of the section. The NDPase staining gives an excellent visualization of microglia, although with this thickness, the intensity of the staining is too high to distinguish single cells. Lectin histochemistry does not visualize microglia throughout the section and, accordingly, is not suited for the optical fractionator. The mean total number of Mac-1+ microglial cells in the unilateral dentate gyrus of the normal young adult male C57BL/6 mouse was estimated to be 12,300 (coefficient of variation (CV)=0.13) with a mean coefficient of error (CE) of 0.06. The perspective of estimating microglial cell numbers using stereology is to establish a solid basis for studying the dynamics of the microglial cell population in the developing and in the injured, diseased and normal adult CNS.

  16. Does Replacing Sodium Excreted in Sweat Attenuate the Health Benefits of Physical Activity?

    Science.gov (United States)

    Turner, Martin J; Avolio, Alberto P

    2016-08-01

    International guidelines suggest limiting sodium intake to 86-100 mmol/day, but average intake exceeds 150 mmol/day. Participants in physical activities are, however, advised to increase sodium intake before, during and after exercise to ensure euhydration, replace sodium lost in sweat, speed rehydration and maintain performance. A similar range of health benefits is attributable to exercise and to reduction in sodium intake, including reductions in blood pressure (BP) and the increase of BP with age, reduced risk of stroke and other cardiovascular diseases, and reduced risk of osteoporosis and dementia. Sweat typically contains 40-60 mmol/L of sodium, leading to approximately 20-90 mmol of sodium lost in one exercise session with sweat rates of 0.5-1.5 L/h. Reductions in sodium intake of 20-90 mmol/day have been associated with substantial health benefits. Homeostatic systems reduce sweat sodium as low as 3-10 mmol/L to prevent excessive sodium loss. "Salty sweaters" may be individuals with high sodium intake who perpetuate their "salty sweat" condition by continual replacement of sodium excreted in sweat. Studies of prolonged high intensity exercise in hot environments suggest that sodium supplementation is not necessary to prevent hyponatremia during exercise lasting up to 6 hr. We examine the novel hypothesis that sodium excreted in sweat during physical activity offsets a significant fraction of excess dietary sodium, and hence may contribute part of the health benefits of exercise. Replacing sodium lost in sweat during exercise may improve physical performance, but may attenuate the long-term health benefits of exercise. PMID:26841436

  17. Andrographolide inhibits NF-κB activation and attenuates neointimal hyperplasia in arterial restenosis

    Institute of Scientific and Technical Information of China (English)

    Yu-Jiu Wang; Jin-Tao Wang; Quan-Xin Fan; Jian-Guo Geng

    2007-01-01

    The NF-κB transcription factors modulate the expression of tissue factor(TF),E-selectin(CD62E)and vascular cell adhesion molecule-1(VCAM-11,which are essential for thrombosis and inflanunation.We have previously shown that andrographolide(Andro)covalently modifies the reduced cysteine62 of p50-a maior subunit of NF-κB transcription factors,thus blocking the binding Of NF-κB transcription factors to the promoters of their target genes,preventing NFκB activation and inhibiting inflammation in vitro and in vivo.Here we report that Andro.but not its inactive structural analog 4H-Andro,significantly suppressed the proliferation of arterial neointima (~60% reduction)in a murine model of arterial restenosis.Consistently,p50-/- mice manifested attenuated neointimal hyperplasia upon arterial ligation.Notably,the same dosage of Andro did not further reduce neointimal formation in p50-/- mice,which implicates the specificity of Andro on p50 for treating experimental arterial restenosis.The upregulation of NF-κB target genes,including TF,Eselectin and VCAM-1,and the increased deposition of leukocytes(mainly CD68+ macrophages)were clearly detected within the iniured arterial walls,all of which were significantly abolished by treatment with Andro or genetic deletion of p50.The expression of TF,E-selectin and VCAM-1 was also markedly upregulated in the patient sample of thrombotic vasculitis,indicating the clinical relevance of NF-κB activation in the pathogeneses of occlusive arterial diseases.Our data thus indicate that,by the downregulation ofthe NF-κB target genes that are critical in thrombosis and inflammation,specific inhibitors of p50,such as Andro,may be therapeutically valuable for preventing and treating thrombotic arterial diseases,including neointimal hyperplasia in arterial restenosis.

  18. Increased severity of experimental autoimmune encephalomyelitis, chronic macrophage/microglial reactivity, and demyelination in transgenic mice producing tumor necrosis factor-alpha in the central nervous system

    DEFF Research Database (Denmark)

    Taupin, V; Renno, T; Bourbonnière, L;

    1997-01-01

    are a target of immune attack. TNF-alpha also regulates macrophage activity which could contribute to autoimmune inflammation. We have expressed TNF-alpha at disease-equivalent levels in the central nervous system of transgenic mice, using a myelin basic protein (MBP) promoter. These mice were normal....../microglial reactivity was evident in demyelinating lesions in spinal cord, but T cells were not detected during chronic disease. The participation of TNF-alpha in the demyelinating process is thus more probably due to the perpetuation of macrophage/microglial activation than to direct cytotoxicity of myelin...

  19. Minocycline Effects on IL-6 Concentration in Macrophage and Microglial Cells in a Rat Model of Neuropathic Pain

    Science.gov (United States)

    Moini-Zanjani, Taraneh; Ostad, Seyed-Nasser; Labibi, Farzaneh; Ameli, Haleh; Mosaffa, Nariman; Sabetkasaei, Masoumeh

    2016-01-01

    Background: Evidence indicates that neuropathic pain pathogenesis is not confined to changes in the activity of neuronal systems but involves interactions between neurons, inflammatory immune and immune-like glial cells. Substances released from immune cells during inflammation play an important role in development and maintenance of neuropathic pain. It has been found that minocycline suppresses the development of neuropathic pain. Here, we evaluated the analgesic effect of minocycline in a chronic constriction injury (CCI) model of neuropathic pain in rat and assessed IL-6 concentration from cultured macrophage and microglia cells. Methods: Male Wistar rat (n=6, 150-200 g) were divided into three different groups: 1) CCI+vehicle, 2) sham+vehicle, and 3) CCI+drug. Minocycline (10, 20, and 40 mg/kg) was injected one hour before surgery and continued daily to day 14 post ligation. Von Frey filaments and acetone, as pain behavioral tests, were used for mechanical allodynia and cold allodynia, respectively. Experiments were performed on day 0 (before surgery) and days 1, 3, 5, 7, 10, and 14 post -injury. At day 14, rats were killed and monocyte-derived macrophage from right ventricle and microglia from lumbar part of the spinal cord were isolated and cultured in RPMI and Leibovitz’s media, respectively. IL-6 concentration was evaluated in cell culture supernatant after 24 h. Results: Minocycline (10, 20, and 40 mg/kg) attenuated pain behavior, and a decrease in IL-6 concentration was observed in immune cells compared to CCI vehicle-treated animals. Conclusion: Minocycline reduced pain behavior and decreased IL-6 concentration in macrophage and microglial cells. PMID:27221523

  20. Activation and Genetic Modification of Human Monocyte-Derived Dendritic Cells using Attenuated Salmonella typhimurium

    Directory of Open Access Journals (Sweden)

    Agnieszka Michael

    2010-01-01

    Full Text Available Live attenuated bacterial vectors, such as Salmonella typhimurium, have shown promise as delivery vehicles for DNA. We have examined two new strains of S. typhimurium and their impact on dendritic cell maturation (CD12-sifA/aroC mutant and WT05-ssaV/aroC, both in TML background. Strain WT05 matured dendritic cells in a more efficient way; caused higher release of cytokines TNF-α, IL-12, IL-1β; and was efficient for gene transfer. These findings suggest that the genetic background of the attenuation can influence the pattern of inflammatory immune response to Salmonella infection.

  1. System xC- is a mediator of microglial function and its deletion slows symptoms in amyotrophic lateral sclerosis mice.

    Science.gov (United States)

    Mesci, Pinar; Zaïdi, Sakina; Lobsiger, Christian S; Millecamps, Stéphanie; Escartin, Carole; Seilhean, Danielle; Sato, Hideyo; Mallat, Michel; Boillée, Séverine

    2015-01-01

    Amyotrophic lateral sclerosis is the most common adult-onset motor neuron disease and evidence from mice expressing amyotrophic lateral sclerosis-causing SOD1 mutations suggest that neurodegeneration is a non-cell autonomous process where microglial cells influence disease progression. However, microglial-derived neurotoxic factors still remain largely unidentified in amyotrophic lateral sclerosis. With excitotoxicity being a major mechanism proposed to cause motor neuron death in amyotrophic lateral sclerosis, our hypothesis was that excessive glutamate release by activated microglia through their system [Formula: see text] (a cystine/glutamate antiporter with the specific subunit xCT/Slc7a11) could contribute to neurodegeneration. Here we show that xCT expression is enriched in microglia compared to total mouse spinal cord and absent from motor neurons. Activated microglia induced xCT expression and during disease, xCT levels were increased in both spinal cord and isolated microglia from mutant SOD1 amyotrophic lateral sclerosis mice. Expression of xCT was also detectable in spinal cord post-mortem tissues of patients with amyotrophic lateral sclerosis and correlated with increased inflammation. Genetic deletion of xCT in mice demonstrated that activated microglia released glutamate mainly through system [Formula: see text]. Interestingly, xCT deletion also led to decreased production of specific microglial pro-inflammatory/neurotoxic factors including nitric oxide, TNFa and IL6, whereas expression of anti-inflammatory/neuroprotective markers such as Ym1/Chil3 were increased, indicating that xCT regulates microglial functions. In amyotrophic lateral sclerosis mice, xCT deletion surprisingly led to earlier symptom onset but, importantly, this was followed by a significantly slowed progressive disease phase, which resulted in more surviving motor neurons. These results are consistent with a deleterious contribution of microglial-derived glutamate during symptomatic

  2. Microglial Aging in the Healthy CNS: Phenotypes, Drivers, and Rejuvenation

    Directory of Open Access Journals (Sweden)

    Wai T Wong

    2013-03-01

    Full Text Available Neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, and age-related macular degeneration, share two characteristics in common: 1 a disease prevalence that increases markedly with advancing age, and 2 neuroinflammatory changes in which microglia, the primary resident immune cell of the CNS, feature prominently. These characteristics have led to the hypothesis that pathogenic mechanisms underlying age-related neurodegenerative disease involve aging changes in microglia. If correct, targeting features of microglial senescence may constitute a feasible therapeutic strategy. This review explores this hypothesis and its implications by considering the current knowledge on how microglia undergo change during aging and how the emergence of these aging phenotypes relate to significant alterations in microglial function. Evidence and theories on cellular mechanisms implicated in driving senescence in microglia are reviewed, as are rejuvenative measures and strategies that aim to reverse or ameliorate the aging microglial phenotype. Understanding and controlling microglial aging may represent an opportunity for elucidating disease mechanisms and for formulating novel therapies.

  3. IFNgamma enhances microglial reactions to hippocampal axonal degeneration

    DEFF Research Database (Denmark)

    Jensen, M B; Hegelund, I V; Lomholt, N D;

    2000-01-01

    periods. Message for the immune cytokine interferon-gamma (IFNgamma) was undetectable, and glial reactivity to axonal lesions occurred as normal in IFNgamma-deficient mice. Microglial responses to lesion-induced neuronal injury were markedly enhanced in myelin basic protein promoter-driven transgenic mice...

  4. Regulatory effects of caffeic acid phenethyl ester on neuroinflammation in microglial cells.

    Science.gov (United States)

    Tsai, Cheng-Fang; Kuo, Yueh-Hsiung; Yeh, Wei-Lan; Wu, Caren Yu-Ju; Lin, Hsiao-Yun; Lai, Sheng-Wei; Liu, Yu-Shu; Wu, Ling-Hsuan; Lu, Jheng-Kun; Lu, Dah-Yuu

    2015-01-01

    Microglial activation has been widely demonstrated to mediate inflammatory processes that are crucial in several neurodegenerative disorders. Pharmaceuticals that can deliver direct inhibitory effects on microglia are therefore considered as a potential strategy to counter balance neurodegenerative progression. Caffeic acid phenethyl ester (CAPE), a natural phenol in honeybee propolis, is known to possess antioxidant, anti-inflammatory and anti-microbial properties. Accordingly, the current study intended to probe the effects of CAPE on microglia activation by using in vitro and in vivo models. Western blot and Griess reaction assay revealed CAPE significantly inhibited the expressions of inducible nitric oxide synthase (NOS), cyclooxygenase (COX)-2 and the production of nitric oxide (NO). Administration of CAPE resulted in increased expressions of hemeoxygenase (HO)-1and erythropoietin (EPO) in microglia. The phosphorylated adenosine monophosphate-activated protein kinase (AMPK)-α was further found to regulate the anti-inflammatory effects of caffeic acid. In vivo results from immunohistochemistry along with rotarod test also revealed the anti-neuroinflammatory effects of CAPE in microglia activation. The current study has evidenced several possible molecular determinants, AMPKα, EPO, and HO-1, in mediating anti-neuroinflammatory responses in microglial cells. PMID:25768341

  5. Regulatory Effects of Caffeic Acid Phenethyl Ester on Neuroinflammation in Microglial Cells

    Directory of Open Access Journals (Sweden)

    Cheng-Fang Tsai

    2015-03-01

    Full Text Available Microglial activation has been widely demonstrated to mediate inflammatory processes that are crucial in several neurodegenerative disorders. Pharmaceuticals that can deliver direct inhibitory effects on microglia are therefore considered as a potential strategy to counter balance neurodegenerative progression. Caffeic acid phenethyl ester (CAPE, a natural phenol in honeybee propolis, is known to possess antioxidant, anti-inflammatory and anti-microbial properties. Accordingly, the current study intended to probe the effects of CAPE on microglia activation by using in vitro and in vivo models. Western blot and Griess reaction assay revealed CAPE significantly inhibited the expressions of inducible nitric oxide synthase (NOS, cyclooxygenase (COX-2 and the production of nitric oxide (NO. Administration of CAPE resulted in increased expressions of hemeoxygenase (HO-1and erythropoietin (EPO in microglia. The phosphorylated adenosine monophosphate-activated protein kinase (AMPK-α was further found to regulate the anti-inflammatory effects of caffeic acid. In vivo results from immunohistochemistry along with rotarod test also revealed the anti-neuroinflammatory effects of CAPE in microglia activation. The current study has evidenced several possible molecular determinants, AMPKα, EPO, and HO-1, in mediating anti-neuroinflammatory responses in microglial cells.

  6. Morphological features of microglial cells in the hippocampal dentate gyrus of Gunn rat: a possible schizophrenia animal model

    OpenAIRE

    Liaury Kristian; Miyaoka Tsuyoshi; Tsumori Toshiko; Furuya Motohide; Wake Rei; Ieda Masa; Tsuchie Keiko; Taki Michiyo; Ishihara Kotomi; Tanra Andi; Horiguchi Jun

    2012-01-01

    Abstract Background Schizophrenia is a debilitating and complex mental disorder whose exact etiology remains unknown. There is growing amount of evidence of a relationship between neuroinflammation, as demonstrated by microglial activation, and schizophrenia. Our previous studies have proposed that hyperbilirubinemia plays a role in the pathophysiology of schizophrenia. Furthermore, we suggested the Gunn rat, an animal model of bilirubin encephalopathy, as a possible animal model of schizophr...

  7. Subpicomolar diphenyleneiodonium inhibits microglial NADPH oxidase with high specificity and shows great potential as a therapeutic agent for neurodegenerative diseases

    OpenAIRE

    Wang, Qingshan; Chu, Chun-Hsien; Oyarzabal, Esteban; Jiang, Lulu; Chen, Shih-Heng; Wilson, Belinda; Qian, Li; Hong, Jau-Shyong

    2014-01-01

    Activation of microglial NADPH oxidase (NOX2) plays a critical role in mediating neuroinflammation, which is closely linked with the pathogenesis of a variety of neurodegenerative diseases, including Parkinson’s disease (PD). The inhibition of NOX2-generated superoxide has become an effective strategy for developing disease-modifying therapies for PD. However, the lack of specific and potent NOX2 inhibitors has hampered the progress of this approach. Diphenyleneiodonium (DPI) is a widely used...

  8. A remediation strategy based on active phytoremediation followed by natural attenuation in a soil contaminated by pyrite waste

    Energy Technology Data Exchange (ETDEWEB)

    Clemente, Rafael [Department of Soil and Water Conservation and Organic Waste Management, Centro de Edafologia y Biologia Aplicada del Segura, CSIC, Campus Universitario de Espinardo, Apartado 164, 30100 Espinardo, Murcia (Spain)]. E-mail: rclemente@cebas.csic.es; Almela, Concepcion [Instituto de Agroquimica y Tecnologia de Alimentos, CSIC, Apartado 73, 46100 Burjassot, Valencia (Spain); Bernal, M. Pilar [Department of Soil and Water Conservation and Organic Waste Management, Centro de Edafologia y Biologia Aplicada del Segura, CSIC, Campus Universitario de Espinardo, Apartado 164, 30100 Espinardo, Murcia (Spain)

    2006-10-15

    Phytoremediation of metal-polluted soils can be promoted by the proper use of soil amendments and agricultural practices. A 4-year phytoremediation programme was applied to a site affected by the toxic spill of pyrite residue at Aznalcollar (Spain) in 1998, contaminated with heavy metals (Zn, Cu, Pb, Cd) and arsenic. This consisted of active phytoremediation, using organic amendments (cow manure and compost) and lime and growing two successive crops of Brassica juncea (L.) Czern., followed by natural attenuation without further intervention. Changes in soil pH, extractable metal and As concentrations, organic carbon content and microbial biomass was evaluated. The initial oxidation of metal sulphides from pyrite residues released soluble metals and reduced soil pH to extremely acidic values (mean 4.1, range 2.0-7.0). The addition of lime (up to 64 t ha{sup -1}) increased soil pH to adequate values for plant growth, resulting in a significant decrease in DTPA-extractable metal concentrations in all plots. Natural attenuation phase showed also a decrease in extractable metals. Organic treatments increased the soil total organic carbon, which led to higher values of microbial biomass (11.6, 15.2 and 14.9 g kg{sup -1} TOC and 123, 170 and 275 {mu}g g{sup -1} biomass-C in control, compost and manure plots, respectively). Active phytoremediation followed by natural attenuation, was effective for remediation of this pyrite-polluted soil. - The addition of lime and organic amendments decreased heavy metal solubility and promoted Natural attenuation of a recently-contaminated soil.

  9. Neuronal Hyperactivity Disturbs ATP Microgradients, Impairs Microglial Motility, and Reduces Phagocytic Receptor Expression Triggering Apoptosis/Microglial Phagocytosis Uncoupling.

    Directory of Open Access Journals (Sweden)

    Oihane Abiega

    2016-05-01

    Full Text Available Phagocytosis is essential to maintain tissue homeostasis in a large number of inflammatory and autoimmune diseases, but its role in the diseased brain is poorly explored. Recent findings suggest that in the adult hippocampal neurogenic niche, where the excess of newborn cells undergo apoptosis in physiological conditions, phagocytosis is efficiently executed by surveillant, ramified microglia. To test whether microglia are efficient phagocytes in the diseased brain as well, we confronted them with a series of apoptotic challenges and discovered a generalized response. When challenged with excitotoxicity in vitro (via the glutamate agonist NMDA or inflammation in vivo (via systemic administration of bacterial lipopolysaccharides or by omega 3 fatty acid deficient diets, microglia resorted to different strategies to boost their phagocytic efficiency and compensate for the increased number of apoptotic cells, thus maintaining phagocytosis and apoptosis tightly coupled. Unexpectedly, this coupling was chronically lost in a mouse model of mesial temporal lobe epilepsy (MTLE as well as in hippocampal tissue resected from individuals with MTLE, a major neurological disorder characterized by seizures, excitotoxicity, and inflammation. Importantly, the loss of phagocytosis/apoptosis coupling correlated with the expression of microglial proinflammatory, epileptogenic cytokines, suggesting its contribution to the pathophysiology of epilepsy. The phagocytic blockade resulted from reduced microglial surveillance and apoptotic cell recognition receptor expression and was not directly mediated by signaling through microglial glutamate receptors. Instead, it was related to the disruption of local ATP microgradients caused by the hyperactivity of the hippocampal network, at least in the acute phase of epilepsy. Finally, the uncoupling led to an accumulation of apoptotic newborn cells in the neurogenic niche that was due not to decreased survival but to delayed

  10. Oxidation of HMGB1 causes attenuation of its pro-inflammatory activity and occurs during liver ischemia and reperfusion.

    Directory of Open Access Journals (Sweden)

    Anding Liu

    Full Text Available High mobility group box 1 (HMGB1 is a nuclear transcription factor. Once HMGB1 is released by damaged cells or activated immune cells, it acts as danger molecule and triggers the inflammatory signaling cascade. Currently, evidence is accumulating that posttranslational modifications such as oxidation may modulate the pro-inflammatory potential of danger signals. We hypothesized that oxidation of HMGB1 may reduce its pro-inflammatory potential and could take place during prolonged ischemia and upon reperfusion.Liver grafts were cold preserved for 24 h and flushed with saline in hourly intervals to collect the effluent. Liver grafts, cold-preserved for 6 h, were transplanted into syngeneic recipients to obtain serum and liver samples 24 h after initiation of reperfusion. Addition of the effluent to a macrophage culture induced the synthesis of tumor necrosis factor-alpha (TNF-α and interleukin (IL-6. The stimulatory activity of graft effluent was reduced after depletion of HMGB1 via immunoprecipitation. Oxidation of the effluent HMGB1 using H(2O(2 attenuated its stimulatory activity as well. Liver transplantation of cold preserved grafts caused HMGB1 translocation and release as determined by immunohistochemistry and ELISA-assay, respectively. Using Western blot with non-reducing conditions revealed the presence of oxidized HMGB1 in liver samples obtained after 12 h and in effluent samples after 16 h of cold preservation as well as in liver and serum samples obtained 24 h after reperfusion.These observations confirm that post-translational oxidation of HMGB1 attenuates its pro-inflammatory activity. Oxidation of HMGB1 as induced during prolonged ischemia and by reoxygenation during reperfusion in vivo might also attenuate its pro-inflammatory activity. Our findings also call for future studies to investigate the mechanism of the inhibitory effect of oxidized HMGB1 on the pro-inflammatory potential.

  11. Microglial cells are involved in the susceptibility of NADPH oxidase knockout mice to 6-hydroxy-dopamine-induced neurodegeneration.

    Directory of Open Access Journals (Sweden)

    Marina S Hernandes

    Full Text Available We explored the impact of Nox-2 in modulating inflammatory-mediated microglial responses in the 6-hydroxydopamine (6-OHDA-induced Parkinson's disease (PD model. Nox1 and Nox2 gene expression were found to increase in striatum, whereas a marked increase of Nox2 expression was observed in substantia nigra (SN of wild-type (wt mice after PD induction. Gp91(phox-/- 6-OHDA-lesioned mice exhibited a significant reduction in the apomorphine-induced rotational behavior, when compared to wt mice. Immunolabeling assays indicated that striatal 6-OHDA injections reduced the number of dopaminergic (DA neurons in the SN of wt mice. In gp91(phox-/- 6-OHDA-lesioned mice the DA degeneration was negligible, suggesting an involvement of Nox in 6-OHDA-mediated SN degeneration. Gp91(phox-/- 6-OHDA-lesioned mice treated with minocycline, a tetracycline derivative that exerts multiple anti-inflammatory effects, including microglial inhibition, exhibited increased apomorphine-induced rotational behavior and degeneration of DA neurons after 6-OHDA injections. The same treatment also increased TNF-α release and potentiated NF-κB activation in the SN of gp91(phox-/--lesioned mice. Our results demonstrate for the first time that inhibition of microglial cells increases the susceptibility of gp91(phox-/- 6-OHDA lesioned mice to develop PD. Blockade of microglia leads to NF-κB activation and TNF-α release into the SN of gp91(phox-/- 6-OHDA lesioned mice, a likely mechanism whereby gp91(phox-/- 6-OHDA lesioned mice may be more susceptible to develop PD after microglial cell inhibition. Nox2 adds an essential level of regulation to signaling pathways underlying the inflammatory response after PD induction.

  12. Induction of xanthine oxidase activity, endoplasmic reticulum stress and caspase activation by sodium metabisulfite in rat liver and their attenuation by Ghrelin.

    Science.gov (United States)

    Ercan, Sevim; Kencebay, Ceren; Basaranlar, Goksun; Derin, Narin; Aslan, Mutay

    2015-02-01

    Sodium metabisulfite is used as a preservative in many food preparations but can oxidize to sulfite radicals initiating molecular oxidation. Ghrelin is a peptide hormone primarily produced in the stomach and has anti-inflammatory and anti-oxidant effects on gastrointestinal and cardiovascular systems. This study was performed to elucidate the effect of ghrelin on sulfite-induced endoplasmic reticulum (ER) stress and caspase activation in rat peripheral organs. Xanthine oxidase (XO), xanthine dehydrogenase (XDH) enzyme activities, ER stress markers [phosphorylated PKR-like ER kinase (pPERK); C/EBP-homologous protein (CHOP)], caspase-3, -8, -9 activities, nuclear factor kappa-B (NF-κB) levels were determined in liver, heart and kidney of rats treated with sodium metabisulfite and/or ghrelin for 5 weeks. Sodium metabisulfite treatment significantly elevated XO activity, induced expression of GRP78, CHOP and increased caspase-3, -8 and -9 activities in liver but had no significant effect in heart and kidney. Ghrelin treatment decreased XO activity to baseline levels and attenuated ER stress and caspase activation in liver tissue of sodium metabisulfite treated rats. In conclusion, metabolism of sodium metabisulfite in liver tissue increased XO activity, induced ER stress and caused caspase activation which was attenuated by ghrelin treatment. Ghrelin's hepatoprotective effect could be through modulation of XO activity.

  13. LPS-induced iNOS expression in N9 microglial cells is suppressed by geniposide via ERK, p38 and nuclear factor-κB signaling pathways.

    Science.gov (United States)

    Zhang, Gu; He, Jun-Lin; Xie, Xiao-Yan; Yu, Chao

    2012-09-01

    Activated microglia producing reactive nitrogen species, inflammatory factors, reactive oxygen species (ROS) and other neurovirulent factors, can lead to the development of neurodegenerative diseases. Certain compounds can inhibit the activation of microglia. However, the mechanisms remain unclear. In the present study, we investigated the inhibitory effect of geniposide on the production of ROS and inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-stimulated N9 murine microglial cells through the p38, ERK1/2 and nuclear factor-κB (NF-κB) signaling pathways. After the N9 cells were pre-treated with the vehicle or geniposide and exposed to LPS for the time indicated, the MTT conversion test was used to assess cell viability. Suitable concentrations were chosen and adjusted according to the experiments. Extracellular nitric oxide (NO) release was measured by Griess reaction. The formation of ROS and intracellular NO was evaluated by fluorescence imaging. NOS activities were determined using commercially available kits. The morphology of the N9 cells was examined by hematoxylin and eosin staining. The expression of iNOS mRNA was examined by RT-PCR. The protein levels of iNOS, p38 mitogen-activated protein kinase (MAPK), ERK1/2 and NF-κB, inhibitory factor-κB-α (IκB-α) were determined by western blot analysis. The results showed that geniposide attenuated the activation of N9 cells and inhibited the overproduction of NO, intracellular ROS and the expression of iNOS induced by LPS in the cells. In addition, geniposide blocked the phosphorylation of p38, ERK1/2 and inhibited the drop-off of IκB induced by LPS in the cells. These data indicate that geniposide has therapeutic potential for the treatment of neurodegenerative diseases, and that it exerts its effects by inhibiting inflammation. PMID:22710392

  14. Acute and chronic stress-induced disturbances of microglial plasticity, phenotype and function.

    Science.gov (United States)

    Walker, Frederick Rohan; Nilsson, Michael; Jones, Kimberley

    2013-10-01

    Traditionally, microglia have been considered to act as macrophages of the central nervous system. While this concept still remains true it is also becoming increasingly apparent that microglia are involved in a host of nonimmunological activities, such as monitoring synaptic function and maintaining synaptic integrity. It has also become apparent that microglia are exquisitely sensitive to perturbation by environmental challenges. The aim of the current review is to critically examine the now substantial literature that has developed around the ability of acute, sub-chronic and chronic stressors to alter microglial structure and function. The vast majority of studies have demonstrated that stress promotes significant structural remodelling of microglia, and can enhance the release of pro-inflammatory cytokines from microglia. Mechanistically, many of these effects appear to be driven by traditional stress-linked signalling molecules, namely corticosterone and norepinephrine. The specific effects of these signalling molecules are, however, complex as they can exert both inhibitory and suppressive effects on microglia depending upon the duration and intensity of exposure. Importantly, research has now shown that these stress-induced microglial alterations, rather than being epiphenomena, have broader behavioural implications, with the available evidence implicating microglia in directly regulating certain aspects of cognitive function and emotional regulation. PMID:24020974

  15. Time course study of microglial and behavioral alterations induced by 6-hydroxydopamine in rats.

    Science.gov (United States)

    Silva, Thiago Pereira da; Poli, Anicleto; Hara, Daniela Balz; Takahashi, Reinaldo Naoto

    2016-05-27

    Understanding the mechanisms responsible for nonmotor manifestations of Parkinson's disease (PD) is crucial in the search for new therapeutic approaches. The aim of the present study was to evaluate the time course of behavioral, neurochemical, and microglial responses after a retrograde partial lesion of the nigrostriatal pathway induced by bilateral injection of 6-hydroxydopamine (6-OHDA). The results showed that 6-OHDA was able to produce both anhedonic and anxiety behaviors; however, an increase of microglial density in some brain areas (substantia nigra, hippocampus and striatum) and deficits in locomotor activity was observed only one week after the lesion. Striatal levels of dopamine (DA) and dihydroxyphenylacetic acid (DOPAC) were reduced by approximately 60% at all times tested. Conversely, increased levels of serotonin (5-HT) and its metabolite were also noted in the striatum only at the first week. These data extend our previous findings and suggest that the retrograde and partial damage of dopaminergic neurons in the substantia nigra can induce effects resembling premotor symptoms of PD, two and three weeks after injury. PMID:27113204

  16. Neuropeptide Y protects cerebral cortical neurons by regulating microglial immune function

    Institute of Scientific and Technical Information of China (English)

    Qijun Li; Changzheng Dong; Wenling Li; Wei Bu; Jiang Wu; Wenqing Zhao

    2014-01-01

    Neuropeptide Y has been shown to inhibit the immunological activity of reactive microglia in the rat cerebral cortex, to reduce N-methyl-D-aspartate current (INMDA) in cortical neurons, and protect neurons. In this study, after primary cultured microglia from the cerebral cortex of rats were treated with lipopolysaccharide, interleukin-1β and tumor necrosis factor-α levels in the cell culture medium increased, and mRNA expression of these cytokines also increased. After primary cultured cortical neurons were incubated with the lipopolysaccharide-treated microg-lial conditioned medium, peak INMDA in neurons increased. These effects of lipopolysaccharide were suppressed by neuropeptide Y. After addition of the neuropeptide Y Y1 receptor antago-nist BIBP3226, the effects of neuropeptide Y completely disappeared. These results suggest that neuropeptide Y prevents excessive production of interleukin-1β and tumor necrosis factor-α by inhibiting microglial reactivity. This reduces INMDA in rat cortical neurons, preventing excitotoxic-ity, thereby protecting neurons.

  17. Does microglial dysfunction play a role in autism and Rett syndrome?

    Science.gov (United States)

    MAEZAWA, IZUMI; CALAFIORE, MARCO; WULFF, HEIKE; JIN, LEE-WAY

    2016-01-01

    Autism spectrum disorders (ASDs) including classic autism is a group of complex developmental disabilities with core deficits of impaired social interactions, communication difficulties and repetitive behaviors. Although the neurobiology of ASDs has attracted much attention in the last two decades, the role of microglia has been ignored. Existing data are focused on their recognized role in neuroinflammation, which only covers a small part of the pathological repertoire of microglia. This review highlights recent findings on the broader roles of microglia, including their active surveillance of brain microenvironments and regulation of synaptic connectivity, maturation of brain circuitry and neurogenesis. Emerging evidence suggests that microglia respond to pre- and postnatal environmental stimuli through epigenetic interface to change gene expression, thus acting as effectors of experience-dependent synaptic plasticity. Impairments of these microglial functions could substantially contribute to several major etiological factors of autism, such as environmental toxins and cortical underconnectivity. Our recent study on Rett syndrome, a syndromic autistic disorder, provides an example that intrinsic microglial dysfunction due to genetic and epigenetic aberrations could detrimentally affect the developmental trajectory without evoking neuroinflammation. We propose that ASDs provide excellent opportunities to study the influence of microglia on neurodevelopment, and this knowledge could lead to novel therapies. PMID:22717189

  18. Attenuation of Immune-Mediated Renal Injury by Telmisartan, an Angiotensin Receptor Blocker and a Selective PPAR-γ Activator

    Directory of Open Access Journals (Sweden)

    Yuki Hamano

    2011-09-01

    Full Text Available Background/Aims: Anti-glomerular basement membrane (GBM nephritis is characterized by activation of the renin-angiotensin system. This study aimed to determine the question of whether a temporary angiotensin II blockade at the initial stage of anti-GBM nephritis is able to attenuate the disease as well as differences in renoprotection among angiotensin II receptor blockers (ARBs with distinct peroxisome proliferator-activated receptor (PPAR-γ-modulating activities. Methods: C57BL/6J mice were immunized with rabbit IgG, followed by intravenous injection of rabbit anti-mouse antibodies. Mice were then treated with telmisartan, losartan, and telmisartan + GW9662 (a PPAR-γ antagonist for 5 days, or hydralazine for 9 days. On days 8 and 13, mice were sacrificed to obtain tissues for histological analysis. Results: The temporary administration of telmisartan significantly suppressed glomerular damage compared to hydralazine. Losartan showed a similar effect but was less effective. Co-administration of GW9662 attenuated the renoprotective effect of telmisartan, almost to levels observed with losartan. In particular, it limited the decreased infiltration of inflammatory cells and preservation of capillaries in the glomeruli induced by telmisartan. Conclusion: Temporary angiotensin II blockade at the initial stage of anti-GBM disease dramatically inhibited its progression. In addition to a class effect of ARBs, telmisartan modified inflammation and endothelial damage in the kidney through its PPAR-γ-agonistic action.

  19. Targeting Attenuated Interferon-α to Myeloma Cells with a CD38 Antibody Induces Potent Tumor Regression with Reduced Off-Target Activity.

    Science.gov (United States)

    Pogue, Sarah L; Taura, Tetsuya; Bi, Mingying; Yun, Yong; Sho, Angela; Mikesell, Glen; Behrens, Collette; Sokolovsky, Maya; Hallak, Hussein; Rosenstock, Moti; Sanchez, Eric; Chen, Haiming; Berenson, James; Doyle, Anthony; Nock, Steffen; Wilson, David S

    2016-01-01

    Interferon-α (IFNα) has been prescribed to effectively treat multiple myeloma (MM) and other malignancies for decades. Its use has waned in recent years, however, due to significant toxicity and a narrow therapeutic index (TI). We sought to improve IFNα's TI by, first, attaching it to an anti-CD38 antibody, thereby directly targeting it to MM cells, and, second, by introducing an attenuating mutation into the IFNα portion of the fusion protein rendering it relatively inactive on normal, CD38 negative cells. This anti-CD38-IFNα(attenuated) immunocytokine, or CD38-Attenukine™, exhibits 10,000-fold increased specificity for CD38 positive cells in vitro compared to native IFNα and, significantly, is ~6,000-fold less toxic to normal bone marrow cells in vitro than native IFNα. Moreover, the attenuating mutation significantly decreases IFNα biomarker activity in cynomolgus macaques indicating that this approach may yield a better safety profile in humans than native IFNα or a non-attenuated IFNα immunocytokine. In human xenograft MM tumor models, anti-CD38-IFNα(attenuated) exerts potent anti-tumor activity in mice, inducing complete tumor regression in most cases. Furthermore, anti-CD38-IFNα(attenuated) is more efficacious than standard MM treatments (lenalidomide, bortezomib, dexamethasone) and exhibits strong synergy with lenalidomide and with bortezomib in xenograft models. Our findings suggest that tumor-targeted attenuated cytokines such as IFNα can promote robust tumor killing while minimizing systemic toxicity. PMID:27611189

  20. Sirtuin 7 promotes cellular survival following genomic stress by attenuation of DNA damage, SAPK activation and p53 response

    International Nuclear Information System (INIS)

    Maintaining the genomic integrity is a constant challenge in proliferating cells. Amongst various proteins involved in this process, Sirtuins play a key role in DNA damage repair mechanisms in yeast as well as mammals. In the present work we report the role of one of the least explored Sirtuin viz., SIRT7, under conditions of genomic stress when treated with doxorubicin. Knockdown of SIRT7 sensitized osteosarcoma (U2OS) cells to DNA damage induced cell death by doxorubicin. SIRT7 overexpression in NIH3T3 delayed cell cycle progression by causing delay in G1 to S transition. SIRT7 overexpressing cells when treated with low dose of doxorubicin (0.25 µM) showed delayed onset of senescence, lesser accumulation of DNA damage marker γH2AX and lowered levels of growth arrest markers viz., p53 and p21 when compared to doxorubicin treated control GFP expressing cells. Resistance to DNA damage following SIRT7 overexpression was also evident by EdU incorporation studies where cellular growth arrest was significantly delayed. When treated with higher dose of doxorubicin (>1 µM), SIRT7 conferred resistance to apoptosis by attenuating stress activated kinases (SAPK viz., p38 and JNK) and p53 response thereby shifting the cellular fate towards senescence. Interestingly, relocalization of SIRT7 from nucleolus to nucleoplasm together with its co-localization with SAPK was an important feature associated with DNA damage. SIRT7 mediated resistance to doxorubicin induced apoptosis and senescence was lost when p53 level was restored by nutlin treatment. Overall, we propose SIRT7 attenuates DNA damage, SAPK activation and p53 response thereby promoting cellular survival under conditions of genomic stress. - Highlights: • Knockdown of SIRT7 sensitized cells to DNA damage induced apoptosis. • SIRT7 delayed onset of premature senescence by attenuating DNA damage response. • Overexpression of SIRT7 delayed cell cycle progression by delaying G1/S transition. • Upon DNA damage SIRT

  1. Sirtuin 7 promotes cellular survival following genomic stress by attenuation of DNA damage, SAPK activation and p53 response

    Energy Technology Data Exchange (ETDEWEB)

    Kiran, Shashi; Oddi, Vineesha [Laboratory of Cancer Biology, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana, 500001 (India); Ramakrishna, Gayatri, E-mail: gayatrirama1@gmail.com [Laboratory of Cancer Biology, Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana, 500001 (India); Laboratory of Cancer Cell Biology, Department of Research, Institute of Liver and Biliary Sciences, Delhi 110070 (India)

    2015-02-01

    Maintaining the genomic integrity is a constant challenge in proliferating cells. Amongst various proteins involved in this process, Sirtuins play a key role in DNA damage repair mechanisms in yeast as well as mammals. In the present work we report the role of one of the least explored Sirtuin viz., SIRT7, under conditions of genomic stress when treated with doxorubicin. Knockdown of SIRT7 sensitized osteosarcoma (U2OS) cells to DNA damage induced cell death by doxorubicin. SIRT7 overexpression in NIH3T3 delayed cell cycle progression by causing delay in G1 to S transition. SIRT7 overexpressing cells when treated with low dose of doxorubicin (0.25 µM) showed delayed onset of senescence, lesser accumulation of DNA damage marker γH2AX and lowered levels of growth arrest markers viz., p53 and p21 when compared to doxorubicin treated control GFP expressing cells. Resistance to DNA damage following SIRT7 overexpression was also evident by EdU incorporation studies where cellular growth arrest was significantly delayed. When treated with higher dose of doxorubicin (>1 µM), SIRT7 conferred resistance to apoptosis by attenuating stress activated kinases (SAPK viz., p38 and JNK) and p53 response thereby shifting the cellular fate towards senescence. Interestingly, relocalization of SIRT7 from nucleolus to nucleoplasm together with its co-localization with SAPK was an important feature associated with DNA damage. SIRT7 mediated resistance to doxorubicin induced apoptosis and senescence was lost when p53 level was restored by nutlin treatment. Overall, we propose SIRT7 attenuates DNA damage, SAPK activation and p53 response thereby promoting cellular survival under conditions of genomic stress. - Highlights: • Knockdown of SIRT7 sensitized cells to DNA damage induced apoptosis. • SIRT7 delayed onset of premature senescence by attenuating DNA damage response. • Overexpression of SIRT7 delayed cell cycle progression by delaying G1/S transition. • Upon DNA damage SIRT

  2. Effects of triptolide on hippocampal microglial cells and astrocytes in the APP/PS1 double transgenic mouse model of Alzheimer’s disease

    Institute of Scientific and Technical Information of China (English)

    Jian-ming Li; Yan Zhang; Liang Tang; Yong-heng Chen; Qian Gao; Mei-hua Bao; Ju Xiang; De-liang Lei

    2016-01-01

    The principal pathology of Alzheimer’s disease includes neuronal extracellular deposition of amyloid-beta peptides and formation of senile pl aques, which in turn induce neuroinlfammation in the brain. Triptolide, a natural extract from the vine-like herb Tripterygium wilfordiiHook F, has potent anti-inlfammatory and immunosuppressive efifcacy. Therefore, we determined if triptolide can inhibit activation and proliferation of microglial cells and astrocytes in the APP/PS1 double transgenic mouse model of Alzheimer’s disease. We used 1 or 5 μg/kg/d triptolide to treat APP/PS1 double transgenic mice (aged 4–4.5 months) for 45 days. Unbiased stereology analysis found that triptolide dose-dependent-ly reduced the total number of microglial cells, and transformed microglial cells into the resting state. Further, triptolide (5 μg/kg/d) also reduced the total number of hippocampal astrocytes. Our in vivo test results indicate that triptolide suppresses activation and proliferation of microglial cells and astrocytes in the hippocampus of APP/PS1 double transgenic mice with Alzheimer’s disease.

  3. Aquaporin-4 deficiency attenuates acute lesions but aggravates delayed lesions and microgliosis after cryoinjury to mouse brain

    Institute of Scientific and Technical Information of China (English)

    Wen-Zhen Shi; Chun-Zhen Zhao; Bing Zhao; Xiao-Liang Zheng; San-Hua Fang; Yun-Bi Lu; Wei-Ping Zhang; Zhong Chen; Er-Qing Wei

    2012-01-01

    Objective To determine whether aquaporin-4 (AQP4) regulates acute lesions,delayed lesions,and the associated microglial activation after cryoinjury to the brain.Methods Brain cryoinjury was applied to AQP4 knockout (KO)and wild-type mice.At 24 h and on days 7 and 14 after cryoinjury,lesion volume,neuronal loss,and densities of microglia and astrocytes were determined,and their changes were compared between AQP4 KO and wild-type mice.Results Lesion volume and neuronal loss in AQP4 KO mice were milder at 24 h following cryoinjury,but worsened on days 7 and 14,compared to those in wild-type mice.Besides,microglial density increased more,and astrocyte proliferation and glial scar formation were attenuated on days 7 and 14 in AQP4 KO mice.Conclusion AQP4 deficiency ameliorates acute lesions,but worsens delayed lesions,perhaps due to the microgliosis in the late phase.

  4. Inhibition of p300 histone acetyltransferase activity in palate mesenchyme cells attenuates Wnt signaling via aberrant E-cadherin expression.

    Science.gov (United States)

    Warner, Dennis R; Smith, Scott C; Smolenkova, Irina A; Pisano, M Michele; Greene, Robert M

    2016-03-01

    p300 is a multifunctional transcriptional coactivator that interacts with numerous transcription factors and exhibits protein/histone acetyltransferase activity. Loss of p300 function in humans and in mice leads to craniofacial defects. In this study, we demonstrated that inhibition of p300 histone acetyltransferase activity with the compound, C646, altered the expression of several genes, including Cdh1 (E-cadherin) in mouse maxillary mesenchyme cells, which are the cells that give rise to the secondary palate. The increased expression of plasma membrane-bound E-cadherin was associated with reduced cytosolic β-catenin, that led to attenuated signaling through the canonical Wnt pathway. Furthermore, C646 reduced both cell proliferation and the migratory ability of these cells. These results suggest that p300 histone acetyltransferase activity is critical for Wnt-dependent palate mesenchymal cell proliferation and migration, both processes that play a significant role in morphogenesis of the palate.

  5. Proteomic analysis of the effects of aged garlic extract and its FruArg component on lipopolysaccharide-induced neuroinflammatory response in microglial cells.

    Directory of Open Access Journals (Sweden)

    Hui Zhou

    Full Text Available Aged garlic extract (AGE is widely used as a dietary supplement, and is claimed to promote human health through anti-oxidant/anti-inflammatory activities with hypolipidemic, antiplatelet and neuroprotective effects. Prior studies of AGE have mainly focused on its organosulfur compounds, with little attention paid to its carbohydrate derivatives, such as N-α-(1-deoxy-D-fructos-1-yl-L-arginine (FruArg. The goal of this study is to investigate actions of AGE and FruArg on antioxidative and neuroinflammatory responses in lipopolysaccharide (LPS-activated murine BV-2 microglial cells using a proteomic approach. Our data show that both AGE and FruArg can significantly inhibit LPS-induced nitric oxide (NO production in BV-2 cells. Quantitative proteomic analysis by combining two dimensional differential in-gel electrophoresis (2D-DIGE with mass spectrometry revealed that expressions of 26 proteins were significantly altered upon LPS exposure, while levels of 20 and 21 proteins exhibited significant changes in response to AGE and FruArg treatments, respectively, in LPS-stimulated BV-2 cells. Notably, approximate 78% of the proteins responding to AGE and FruArg treatments are in common, suggesting that FruArg is a major active component of AGE. MULTICOM-PDCN and Ingenuity Pathway Analyses indicate that the proteins differentially affected by treatment with AGE and FruArg are involved in inflammatory responses and the Nrf2-mediated oxidative stress response. Collectively, these results suggest that AGE and FruArg attenuate neuroinflammatory responses and promote resilience in LPS-activated BV-2 cells by suppressing NO production and by regulating expression of multiple protein targets associated with oxidative stress.

  6. Curcumin Attenuated Bupivacaine-Induced Neurotoxicity in SH-SY5Y Cells Via Activation of the Akt Signaling Pathway.

    Science.gov (United States)

    Fan, You-Ling; Li, Heng-Chang; Zhao, Wei; Peng, Hui-Hua; Huang, Fang; Jiang, Wei-Hang; Xu, Shi-Yuan

    2016-09-01

    Bupivacaine is widely used for regional anesthesia, spinal anesthesia, and pain management. However, bupivacaine could cause neuronal injury. Curcumin, a low molecular weight polyphenol, has a variety of bioactivities and may exert neuroprotective effects against damage induced by some stimuli. In the present study, we tested whether curcumin could attenuate bupivacaine-induced neurotoxicity in SH-SY5Y cells. Cell injury was evaluated by examining cell viability, mitochondrial damage and apoptosis. We also investigated the levels of activation of the Akt signaling pathway and the effect of Akt inhibition by triciribine on cell injury following bupivacaine and curcumin treatment. Our findings showed that the bupivacaine treatment could induce neurotoxicity. Pretreatment of the SH-SY5Y cells with curcumin significantly attenuated bupivacaine-induced neurotoxicity. Interestingly, the curcumin treatment increased the levels of Akt phosphorylation. More significantly, the pharmacological inhibition of Akt abolished the cytoprotective effect of curcumin against bupivacaine-induced cell injury. Our data suggest that pretreating SH-SY5Y cells with curcumin provides a protective effect on bupivacaine-induced neuronal injury via activation of the Akt signaling pathway. PMID:27233246

  7. Direct optical activation of skeletal muscle fibres efficiently controls muscle contraction and attenuates denervation atrophy.

    Science.gov (United States)

    Magown, Philippe; Shettar, Basavaraj; Zhang, Ying; Rafuse, Victor F

    2015-10-13

    Neural prostheses can restore meaningful function to paralysed muscles by electrically stimulating innervating motor axons, but fail when muscles are completely denervated, as seen in amyotrophic lateral sclerosis, or after a peripheral nerve or spinal cord injury. Here we show that channelrhodopsin-2 is expressed within the sarcolemma and T-tubules of skeletal muscle fibres in transgenic mice. This expression pattern allows for optical control of muscle contraction with comparable forces to nerve stimulation. Force can be controlled by varying light pulse intensity, duration or frequency. Light-stimulated muscle fibres depolarize proportionally to light intensity and duration. Denervated triceps surae muscles transcutaneously stimulated optically on a daily basis for 10 days show a significant attenuation in atrophy resulting in significantly greater contractile forces compared with chronically denervated muscles. Together, this study shows that channelrhodopsin-2/H134R can be used to restore function to permanently denervated muscles and reduce pathophysiological changes associated with denervation pathologies.

  8. Selective Activation of At2 Receptor Attenuates Progression of Pulmonary Hypertension and Inhibits Cardiopulmonary Fibrosis

    DEFF Research Database (Denmark)

    Bruce, E; Shenoy, V; Rathinasabapathy, A;

    2015-01-01

    -ventricular hemodynamic parameters were measured and tissues collected for gene expression and histological analyses. KEY RESULTS: Initiation of C21 treatment significantly attenuated much of the pathophysiology associated with MCT-induced PH. Most notably, C21 reversed pulmonary fibrosis and prevented right ventricular...... fibrosis. These beneficial effects were associated with improvement in right heart function, decreased pulmonary vessel wall thickness, reduced pro-inflammatory cytokines, and favorable modulation of the lung RAS. Conversely, co-administration of the AT2 receptor antagonist, PD-123319, or the Mas......BACKGROUND AND PURPOSE: Pulmonary hypertension (PH) is a devastating disease characterized by increased pulmonary arterial pressure, which progressively leads to right heart failure and death. A dysregulated renin angiotensin system (RAS) has been implicated in the development and progression of PH...

  9. HIF-1α Activation Attenuates IL-6 and TNF-α Pathways in Hippocampus of Rats Following Transient Global Ischemia

    Directory of Open Access Journals (Sweden)

    Jihong Xing

    2016-07-01

    Full Text Available Background/Aims: This study was to examine the role played by hypoxia inducible factor-1 (HIF-1α in regulating pro-inflammatory cytokines (PICs pathway in the rat hippocampus after cardiac arrest (CA induced-transient global ischemia followed by cardiopulmonary resuscitation (CPR. Those PICs include interleukin-1β (IL-1β, interleukin-6 (IL-6 and tumor necrosis factor-α (TNF-α. Methods: A rat model of CA induced by asphyxia was used in the current study. Following CPR, the hippocampus CA1 region was obtained for ELISA to determine the levels of HIF-1α and PICs; and Western Blot analysis to determine the protein levels of PIC receptors. Results: Our data show that IL-1β, IL-6 and TNF-α were significant elevated in the hippocampus after CPR as compared with control group. This was companied with increasing of HIF-1α and the time courses for HIF-1α and PICs were similar. In addition, PIC receptors, namely IL-1R, IL-6R and TNFR1 were upregulated in CA rats. Also, stimulation of HIF-1α by systemic administration of ML228, HIF-1α activator, significantly attenuated the amplified IL-6/IL-6R and TNF-α /TNFR1 pathway in the hippocampus of CA rats, but did not modify IL-1β and its receptor. Moreover, ML228 attenuated upregulated expression of Caspase-3 indicating cell apoptosis evoked by CA. Conclusion: Transient global ischemia induced by CA increases the levels of IL-1β, IL-6 and TNF-α and thereby leads to enhancement in their respective receptor in the rat hippocampus. Stabilization of HIF-1α plays a role in attenuating amplified expression IL-6R, TNFR1 and Caspase-3 in the processing of transient global ischemia. Results of our study suggest that PICs contribute to cerebral injuries evoked by transient global ischemia and in this pathophysiological process activation of HIF-1α improves tissues against ischemic injuries. Our data revealed specific signaling pathways in alleviating CA-evoked global cerebral ischemia by elucidating that

  10. Ultra-low dose naltrexone attenuates chronic morphine-induced gliosis in rats

    Directory of Open Access Journals (Sweden)

    Milne Brian

    2010-04-01

    Full Text Available Abstract Background The development of analgesic tolerance following chronic morphine administration can be a significant clinical problem. Preclinical studies demonstrate that chronic morphine administration induces spinal gliosis and that inhibition of gliosis prevents the development of analgesic tolerance to opioids. Many studies have also demonstrated that ultra-low doses of naltrexone inhibit the development of spinal morphine antinociceptive tolerance and clinical studies demonstrate that it has opioid sparing effects. In this study we demonstrate that ultra-low dose naltrexone attenuates glial activation, which may contribute to its effects on attenuating tolerance. Results Spinal cord sections from rats administered chronic morphine showed significantly increased immuno-labelling of astrocytes and microglia compared to saline controls, consistent with activation. 3-D images of astrocytes from animals administered chronic morphine had significantly larger volumes compared to saline controls. Co-injection of ultra-low dose naltrexone attenuated this increase in volume, but the mean volume differed from saline-treated and naltrexone-treated controls. Astrocyte and microglial immuno-labelling was attenuated in rats co-administered ultra-low dose naltrexone compared to morphine-treated rats and did not differ from controls. Glial activation, as characterized by immunohistochemical labelling and cell size, was positively correlated with the extent of tolerance developed. Morphine-induced glial activation was not due to cell proliferation as there was no difference observed in the total number of glial cells following chronic morphine treatment compared to controls. Furthermore, using 5-bromo-2-deoxyuridine, no increase in spinal cord cell proliferation was observed following chronic morphine administration. Conclusion Taken together, we demonstrate a positive correlation between the prevention of analgesic tolerance and the inhibition of

  11. Possible impact of microglial cells and the monocyte-macrophage system on suicidal behavior.

    Science.gov (United States)

    Steiner, Johann; Gos, Tomasz; Bogerts, Bernhard; Bielau, Hendrik; Drexhage, Hemmo A; Bernstein, Hans-Gert

    2013-11-01

    Immune dysfunction, including monocytosis, increased blood levels of interleukin-1 (IL-1), interleukin-6 (IL- 6) and tumor necrosis factor-alpha (TNF-alpha), as well as an increased microglial density in certain brain areas, have been described in schizophrenia and depression. Interestingly, similar immune alterations have been observed in suicide patients regardless of their underlying psychiatric diagnosis. This review summarizes relevant data from previous studies that have examined peripheral blood, cerebrospinal fluid and human brains (using postmortem histology and in vivo positron emission tomography) to investigate immune mechanisms in suicidal patients. We discuss whether the observed findings indicate that microgliosis and monocyte-macrophage system activation may be a useful marker of disease acuity/severity or whether they instead indicate a distinct neurobiology of suicide. Notably, pathophysiological mechanisms could change during the long-term course of psychiatric diseases. Therefore, different patterns of immune activation may be observed when comparing newly diseased patients with those who are chronically ill.

  12. Propofol pretreatment attenuates lipopolysaccharide-induced acute lung injury in rats by activating the phosphoinositide-3-kinase/Akt pathway

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, L.L. [Department of Anesthesiology, The Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu Province (China); Hu, G.C. [Department of Pharmacology, College of Medicine, University of Illinois at Chicago, Chicago, IL (United States); Zhu, S.S. [Department of Anesthesiology, The Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu Province (China); Li, J.F. [Department of Anesthesiology, Tengzhou Central People' s Hospital, Liaocheng, Shandong Province (China); Liu, G.J. [Department of Anesthesiology, The Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu Province (China)

    2014-10-14

    The aim of this study was to investigate the effect of propofol pretreatment on lipopolysaccharide (LPS)-induced acute lung injury (ALI) and the role of the phosphoinositide-3-kinase/protein kinase B (PI3K/Akt) pathway in this procedure. Survival was determined 48 h after LPS injection. At 1 h after LPS challenge, the lung wet- to dry-weight ratio was examined, and concentrations of protein, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) in bronchoalveolar lavage fluid (BALF) were determined using the bicinchoninic acid method or ELISA. Lung injury was assayed via lung histological examination. PI3K and p-Akt expression levels in the lung tissue were determined by Western blotting. Propofol pretreatment prolonged survival, decreased the concentrations of protein, TNF-α, and IL-6 in BALF, attenuated ALI, and increased PI3K and p-Akt expression in the lung tissue of LPS-challenged rats, whereas treatment with wortmannin, a PI3K/Akt pathway specific inhibitor, blunted this effect. Our study indicates that propofol pretreatment attenuated LPS-induced ALI, partly by activation of the PI3K/Akt pathway.

  13. Immobilized nickel hexacyanoferrate on activated carbons for efficient attenuation of radio toxic Cs(I) from aqueous solutions

    Science.gov (United States)

    Lalhmunsiama; Lalhriatpuia, C.; Tiwari, Diwakar; Lee, Seung-Mok

    2014-12-01

    The aim of this study is to immobilize nickel hexacyanoferrate onto the large surface of activated carbons (ACs) precursor to rice hulls and areca nut waste materials. These nickel hexacyanoferrate immobilized materials are then assessed in the effective attenuation of radio logically important cesium ions from aqueous solutions. The solid samples are characterized by the XRD analytical method and surface morphology is obtained from the SEM images. The batch reactor experiments show that an increase in sorptive pH (2.0-10.0) apparently not affecting the high percent uptake of Cs(I). Equilibrium modeling studies suggest that the data are reasonably and relatively fitted well to the Langmuir adsorption isotherm. Kinetic studies show that sorption process is fairly rapid and the kinetic data are fitted well to the pseudo-second order rate model. Increasing the background electrolyte concentration from 0.001 to 0.1 mol/L NaCl causes insignificant decrease in Cs(I) removal which infers the higher selectivity of these materials for Cs(I) from aqueous solutions. Further, the column reactor operations enable to obtain the breakthrough data which are then fitted to the Thomas non-linear equation as to obtain the loading capacity of column for Cs(I). The results show that the modified materials show potential applicability in the attenuation of radio toxic cesium from aqueous solution.

  14. Minocycline attenuates post-operative cognitive impairment in aged mice by inhibiting microglia activation.

    Science.gov (United States)

    Wang, Hui-Lin; Liu, Hua; Xue, Zhang-Gang; Liao, Qing-Wu; Fang, Hao

    2016-09-01

    Although it is known that isoflurane exposure or surgery leads to post-operative cognitive dysfunction in aged rodents, there are few clinical interventions and treatments available to prevent this disorder. Minocycline (MINO) produces neuroprotection from several neurodegenerative diseases and various experimental animal models. Therefore, we set out to investigate the effects of MINO pre-treatment on isoflurane or surgery induced cognitive impairment in aged mice by assessing the hippocampal-dependent spatial memory performance using the Morris water maze task. Hippocampal tissues were isolated from mice and evaluated by Western blot analysis, immunofluorescence procedures and protein array system. Our results elucidate that MINO down-regulated the isoflurane-induced and surgery-induced enhancement in the protein levels of pro-inflammatory cytokine tumour necrosis factor alpha, interleukin (IL)-1β, interferon-γ and microglia marker Iba-1, and up-regulated protein levels of the anti-inflammatory cytokine IL-4 and IL-10. These findings suggest that pre-treatment with MINO attenuated isoflurane or surgery induced cognitive impairment by inhibiting the overactivation of microglia in aged mice. PMID:27061744

  15. Activity-dependent control of neuronal output by local and global dendritic spike attenuation.

    Science.gov (United States)

    Remy, Stefan; Csicsvari, Jozsef; Beck, Heinz

    2009-03-26

    Neurons possess elaborate dendritic arbors which receive and integrate excitatory synaptic signals. Individual dendritic subbranches exhibit local membrane potential supralinearities, termed dendritic spikes, which control transfer of local synaptic input to the soma. Here, we show that dendritic spikes in CA1 pyramidal cells are strongly regulated by specific types of prior input. While input in the linear range is without effect, supralinear input inhibits subsequent spikes, causing them to attenuate and ultimately fail due to dendritic Na(+) channel inactivation. This mechanism acts locally within the boundaries of the input branch. If an input is sufficiently strong to trigger axonal action potentials, their back-propagation into the dendritic tree causes a widespread global reduction in dendritic excitability which is prominent after firing patterns occurring in vivo. Together, these mechanisms control the capability of individual dendritic branches to trigger somatic action potential output. They are invoked at frequencies encountered during learning, and impose limits on the storage and retrieval rates of information encoded as branch excitability. PMID:19323999

  16. Attenuation of empennage buffet response through active control of damping using piezoelectric material

    Science.gov (United States)

    Heeg, Jennifer; Miller, Jonathan M.; Doggett, Robert V., Jr.

    1993-01-01

    Dynamic response and damping data obtained from buffet studies conducted in a low-speed wind tunnel by using a simple, rigid model attached to spring supports are presented. The two parallel leaf spring supports provided a means for the model to respond in a vertical translation mode, thus simulating response in an elastic first bending mode. Wake-induced buffeting flow was created by placing an airfoil upstream of the model of that the wake of the airfoil impinged on the model. Model response was sensed by a strain gage mounted on one of the springs. The output signal from the strain gage was fed back through a control law implemented on a desktop computer. The processed signals were used to 'actuate' a piezoelectric bending actuator bonded to the other spring in such a way as to add damping as the model responded. The results of this 'proof-of-concept' study show that the piezoelectric actuator was effective in attenuating the wake-induced buffet response over the range of parameters investigated.

  17. Pharmacological activation of cannabinoid 2 receptor attenuates inflammation, fibrogenesis, and promotes re-epithelialization during skin wound healing.

    Science.gov (United States)

    Wang, Lin-Lin; Zhao, Rui; Li, Jiao-Yong; Li, Shan-Shan; Liu, Min; Wang, Meng; Zhang, Meng-Zhou; Dong, Wen-Wen; Jiang, Shu-Kun; Zhang, Miao; Tian, Zhi-Ling; Liu, Chang-Sheng; Guan, Da-Wei

    2016-09-01

    Previous studies showed that cannabinoid 2 (CB2) receptor is expressed in multiple effector cells during skin wound healing. Meanwhile, its functional involvement in inflammation, fibrosis, and cell proliferation in other organs and skin diseases implied CB2 receptor might also regulate skin wound healing. To verify this hypothesis, mice excisional wounds were created and treated with highly selective CB2 receptor agonist GP1a (1-(2,4-dichlorophenyl)-6-methyl- N-piperidin-1-yl-4H-indeno[1,2-c]pyrazole-3-carboxamide) and antagonist AM630 ([6-iodo-2- methyl-1-(2-morpholin-4-ylethyl)indol-3-yl]-(4-methoxyphenyl)methanone) respectively. The inflammatory infiltration, cytokine expression, fibrogenesis, and wound re-epithelialization were analyzed. After CB2 receptor activation, neutrophil and macrophage infiltrations were reduced, and expressions of monocyte chemotactic protein (MCP)-1, stromal cell-derived factor (SDF)-1, Interleukin (IL)-6, IL-1β, tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-β1 and vascular endothelial growth factor (VEGF)-A were decreased. Keratinocyte proliferation and migration were enhanced. Wound re-epithelialization was accelerated. Fibroblast accumulation and fibroblast-to-myofibroblast transformation were attenuated, and expression of pro-collagen I was decreased. Furthermore, HaCaT cells in vitro were treated with GP1a or AM630, which revealed that CB2 receptor activation promoted keratinocyte migration by inducing the epithelial to mesenchymal transition. These results, taken together, indicate that activating CB2 receptor could ameliorate wound healing by reducing inflammation, accelerating re-epithelialization, and attenuating scar formation. Thus, CB2 receptor agonist might be a novel perspective for skin wound therapy. PMID:27268717

  18. Microglial Amyloid-β1-40 Phagocytosis Dysfunction Is Caused by High-Mobility Group Box Protein-1: Implications for the Pathological Progression of Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Kazuyuki Takata

    2012-01-01

    Full Text Available In Alzheimer disease (AD patient brains, the accumulation of amyloid-β (Aβ peptides is associated with activated microglia. Aβ is derived from the amyloid precursor protein; two major forms of Aβ, that is, Aβ1-40 (Aβ40 and Aβ1-42 (Aβ42, exist. We previously reported that rat microglia phagocytose Aβ42, and high mobility group box protein 1 (HMGB1, a chromosomal protein, inhibits phagocytosis. In the present study, we investigated the effects of exogenous HMGB1 on rat microglial Aβ40 phagocytosis. In the presence of exogenous HMGB1, Aβ40 markedly increased in microglial cytoplasm, and the reduction of extracellular Aβ40 was inhibited. During this period, HMGB1 was colocalized with Aβ40 in the cytoplasm. Furthermore, exogenous HMGB1 inhibited the degradation of Aβ40 induced by the rat microglial cytosolic fraction. Thus, extracellular HMGB1 may internalize with Aβ40 in the microglial cytoplasm and inhibit Aβ40 degradation by microglia. This may subsequently delay Aβ40 clearance. We further confirmed that in AD brains, the parts of senile plaques surrounded by activated microglia are composed of Aβ40, and extracellular HMGB1 is deposited on these plaques. Taken together, microglial Aβ phagocytosis dysfunction may be caused by HMGB1 that accumulates extracellularly on Aβ plaques, and it may be critically involved in the pathological progression of AD.

  19. A microglial hypothesis of globoid cell leukodystrophy pathology.

    Science.gov (United States)

    Nicaise, Alexandra M; Bongarzone, Ernesto R; Crocker, Stephen J

    2016-11-01

    Globoid cell leukodystrophy (GLD), also known as Krabbe's disease, is a fatal demyelinating disease accompanied by the formation of giant, multinucleated cells called globoid cells. Previously believed to be a byproduct of inflammation, these cells can be found early in disease before evidence of any damage. The precise mechanism by which these globoid cells cause oligodendrocyte dysfunction is not completely understood, nor is their cell type defined. This Review outlines the idea that microglial cells are transformed into an unknown and undefined novel M3 phenotype in GLD, which is cytotoxic to oligodendrocytes, leading to disease progression. © 2016 Wiley Periodicals, Inc. PMID:27638591

  20. Cytopathic changes and pro-inflammatory cytokines induced by Naegleria fowleri trophozoites in rat microglial cells and protective effects of an anti-Nfa1 antibody.

    Science.gov (United States)

    Oh, Y-H; Jeong, S-R; Kim, J-H; Song, K-J; Kim, K; Park, S; Sohn, S; Shin, H-J

    2005-12-01

    Naegleria fowleri, a free-living amoeba, causes fatal primary amoebic meningoencephalitis in experimental animals and humans. The nfa1 gene (360 bp) was previously cloned from a cDNA library of pathogenic N. fowleri by immunoscreening, and produced a 13.1-kDa recombinant protein that showed pseudopodia-specific localization by immunocytochemistry. On the basis of an idea that the pseudopodia-specific Nfa1 protein seems to be involved in the pathogenicity of N. fowleri, the cytopathic activity of N. fowleri trophozoites co-cultured with rat microglial cells was observed, and the effects of an anti-Nfa1 antibody in a co-culture system were elucidated. Using light, scanning and transmission electron microscopy, it was seen that N. fowleri trophozoites in contact with microglial cells produced vigorous pseudopodia and a food-cup structure. Microglial cells were destroyed by N. fowleri trophozoites as seen from necrotic cell death in a time-dependent manner. In a(51)Cr release assay, N. fowleri showed 17.8%, 24.9%, 54.6% and 98% cytotoxicity against microglial cells at 3, 6, 12 and 24 h post-incubation, respectively. However, when anti-Nfa1 antibody was added in a coculture system, N. fowleri cytotoxicity was reduced to 15.5%, 20.3%, 46.7% and 66.9%, respectively. Moreover, microglial cells co-cultured with N. fowleri trophozoites secreted the pro-inflammatory cytokines, TNF-alpha, IL-1beta and IL-6. In the presence of anti-Nfa1 antibody, the secretion of TNF-alpha was slightly, but not significantly, decreased.

  1. Honokiol activates the LKB1–AMPK signaling pathway and attenuates the lipid accumulation in hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Min Suk; Kim, Jung Hwan; Kim, Hye Jung; Chang, Ki Churl; Park, Sang Won, E-mail: parksw@gnu.ac.kr

    2015-04-15

    Honokiol is a bioactive neolignan compound isolated from the species of Magnolia. This study was designed to elucidate the cellular mechanism by which honokiol alleviates the development of non-alcoholic steatosis. HepG2 cells were treated with honokiol for 1 h, and then exposed to 1 mM free fatty acid (FFA) for 24 h to simulate non-alcoholic steatosis in vitro. C57BL/6 mice were fed with a high-fat diet for 28 days, and honokiol (10 mg/kg/day) was daily treated. Honokiol concentration-dependently attenuated intracellular fat overloading and triglyceride (TG) accumulation in FFA-exposed HepG2 cells. These effects were blocked by pretreatment with an AMP-activated protein kinase (AMPK) inhibitor. Honokiol significantly inhibited sterol regulatory element-binding protein-1c (SREBP-1c) maturation and the induction of lipogenic proteins, stearoyl-CoA desaturase-1 (SCD-1) and fatty acid synthase (FAS) in FFA-exposed HepG2 cells, but these effects were blocked by pretreatment of an AMPK inhibitor. Honokiol induced AMPK phosphorylation and subsequent acetyl-CoA carboxylase (ACC) phosphorylation, which were inhibited by genetic deletion of liver kinase B1 (LKB1). Honokiol stimulated LKB1 phosphorylation, and genetic deletion of LKB1 blocked the effect of honokiol on SREBP-1c maturation and the induction of SCD-1 and FAS proteins in FFA-exposed HepG2 cells. Honokiol attenuated the increases in hepatic TG and lipogenic protein levels and fat accumulation in the mice fed with high-fat diet, while significantly induced LKB1 and AMPK phosphorylation. Taken together, our findings suggest that honokiol has an anti-lipogenic effect in hepatocytes, and this effect may be mediated by the LKB1–AMPK signaling pathway, which induces ACC phosphorylation and inhibits SREBP-1c maturation in hepatocytes. - Highlights: • Honokiol attenuates lipid accumulation induced by free fatty acid in hepatocyte. • Honokiol inhibits the increase in lipogenic enzyme levels induced by free fatty

  2. Thy-1 attenuates TNF-alpha-activated gene expression in mouse embryonic fibroblasts via Src family kinase.

    Directory of Open Access Journals (Sweden)

    Bin Shan

    Full Text Available Heterogeneous surface expression of Thy-1 in fibroblasts modulates inflammation and may thereby modulate injury and repair. As a paradigm, patients with idiopathic pulmonary fibrosis, a disease with pathologic features of chronic inflammation, demonstrate an absence of Thy-1 immunoreactivity within areas of fibrotic activity (fibroblast foci in contrast to the predominant Thy-1 expressing fibroblasts in the normal lung. Likewise, Thy-1 deficient mice display more severe lung fibrosis in response to an inflammatory injury than wildtype littermates. We investigated the role of Thy-1 in the response of fibroblasts to the pro-inflammatory cytokine TNF-alpha. Our study demonstrates distinct profiles of TNF-alpha-activated gene expression in Thy-1 positive (Thy-1+ and negative (Thy-1- subsets of mouse embryonic fibroblasts (MEF. TNF-alpha induced a robust activation of MMP-9, ICAM-1, and the IL-8 promoter driven reporter in Thy-1- MEFs, in contrast to only a modest increase in Thy-1+ counterparts. Consistently, ectopic expression of Thy-1 in Thy-1- MEFs significantly attenuated TNF-alpha-activated gene expression. Mechanistically, TNF-alpha activated Src family kinase (SFK only in Thy-1- MEFs. Blockade of SFK activation abrogated TNF-alpha-activated gene expression in Thy-1- MEFs, whereas restoration of SFK activation rescued the TNF-alpha response in Thy-1+ MEFs. Our findings suggest that Thy-1 down-regulates TNF-alpha-activated gene expression via interfering with SFK- and NF-kappaB-mediated transactivation. The current study provides a novel mechanistic insight to the distinct roles of fibroblast Thy-1 subsets in inflammation.

  3. Turo (Qi Dance Training Attenuates Psychological Symptoms and Sympathetic Activation Induced by Mental Stress in Healthy Women

    Directory of Open Access Journals (Sweden)

    Hwa-Jin Lee

    2009-01-01

    Full Text Available Vagal withdrawal and sympathetic overactivity accompany various types of stress. Qi training is reported to reduce sympathetic hyper-reactivity in a stressful situation. Turo, which is a type of dance that uses the Meridian Qi System, may reduce the psychological symptoms induced by an imbalance of the autonomic nervous system (ANS. We observed whether Turo training alters psychopathological and psychological symptoms using the Symptom Checklist 90-Revision (SCL-90-R and examined whether it attenuates the stress response to mental stress in healthy adolescent females using the power spectrum analysis of heart rate variability (HRV. Twenty-one subjects received Turo training and 27 subjects were trained with mimicking movements. The SCL-90-R was measured before and after the 2-month training period. Heart rate (HR, total power (TP and the LF/HF ratio of HRV were compared between the Turo and control groups during and after mental stress. The somatization and hostility subscales of the SCL-90-R of the Turo group were significantly lower than those of the control group after 2 months. The increases in HR and the LF/HF ratio of HRV induced by the stress test were significantly lower in the Turo group than in the control group. The TP of the Turo group was significantly higher than that of the control group. The psychological symptoms and sympathetic activation induced by the artificial stress were significantly reduced by the Turo training. These findings suggest that Turo training can play a critical role in attenuating psychological symptoms and stress-induced sympathetic activation.

  4. Influence of Vertical Attenuation of Photosynthetically Active Radiation on the Growth of Submerged Aquatic Vegetation in Tropical Reservoir.

    Science.gov (United States)

    da Silva Rotta, L. H.; Mishra, D. R.; Alcântara, E. H.; Imai, N. N.

    2015-12-01

    Reservoir construction cause many changes in lotic ecosystems and can favor the aquatic macrophyte growth. Nova Avanhandava Reservoir (São Paulo, Brazil), is fully inhabited by submerged aquatic vegetation (SAV) which may cause serious problems to hydropower and irrigation systems. The goal of this study was to assess the radiation availability in the water column in Nova Avanhandava and analyze its influence on SAV development and growth. The measurements were carried out between 28th and 30th June, 2013, at 19 sampling stations. Water samples for analytical determination of the suspended solids and chlorophyll-a concentration were collected. Hyperspectral downwelling irradiance (Ed) data, at several depths, were measured using the TriOS/RAMSES optical sensor. Depths and SAV heights were collected through hydroacoustic measurements by transects using the scientific digital sonar BioSonics DT-X (Echosounder). The Ed data were normalized, than calculated the Kd PAR - downwelling diffuse attenuation coefficient of photosynthetically active radiation, and the euphotic zone depth (ZEZ). Results showed that SAV height values were lower at upstream (around P01) with highest TSS (Total Suspended Solids) and Kd, compared to areas downstream (around P19) (Figure). The maximum depth of SAV development, average SAV height, maximum SAV height, variability, and depth of occurrence of SAV were primarily influenced by Kd. A linear inverse relationship between the average SAV height and the Kd PAR (R2 = 0.56, p<0.001), and between maximum SAV height and Kd PAR (R²=0.5, p<0.001) demonstrated that the SAV heigth can be estimated by Kd PAR with significant accuracy. Therefore, studies on subaquatic radiation availability measured by the vertical attenuation of Ed PAR in the water column and the optically active components can be effiectivly linked to SAV growth and occurrence and aid in understanding SAV in tropical reservoirs, contributing to its management.

  5. Developmental changes in microglial mobilization are independent of apoptosis in the neonatal mouse hippocampus.

    Science.gov (United States)

    Eyo, Ukpong B; Miner, Samuel A; Weiner, Joshua A; Dailey, Michael E

    2016-07-01

    During CNS development, microglia transform from highly mobile amoeboid-like cells to primitive ramified forms and, finally, to highly branched but relatively stationary cells in maturity. The factors that control developmental changes in microglia are largely unknown. Because microglia detect and clear apoptotic cells, developmental changes in microglia may be controlled by neuronal apoptosis. Here, we assessed the extent to which microglial cell density, morphology, motility, and migration are regulated by developmental apoptosis, focusing on the first postnatal week in the mouse hippocampus when the density of apoptotic bodies peaks at postnatal day 4 and declines sharply thereafter. Analysis of microglial form and distribution in situ over the first postnatal week showed that, although there was little change in the number of primary microglial branches, microglial cell density increased significantly, and microglia were often seen near or engulfing apoptotic bodies. Time-lapse imaging in hippocampal slices harvested at different times over the first postnatal week showed differences in microglial motility and migration that correlated with the density of apoptotic bodies. The extent to which these changes in microglia are driven by developmental neuronal apoptosis was assessed in tissues from BAX null mice lacking apoptosis. We found that apoptosis can lead to local microglial accumulation near apoptotic neurons in the pyramidal cell body layer but, unexpectedly, loss of apoptosis did not alter overall microglial cell density in vivo or microglial motility and migration in ex vivo tissue slices. These results demonstrate that developmental changes in microglial form, distribution, motility, and migration occur essentially normally in the absence of developmental apoptosis, indicating that factors other than neuronal apoptosis regulate these features of microglial development. PMID:26576723

  6. A novel natural Nrf2 activator with PPARγ-agonist (monascin) attenuates the toxicity of methylglyoxal and hyperglycemia

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Wei-Hsuan; Lee, Bao-Hong; Chang, Yu-Ying [Department of Biochemical Science and Technology, College of Life Science, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan (China); Hsu, Ya-Wen [SunWay Biotechnology Company, Taipei, Taiwan (China); Pan, Tzu-Ming, E-mail: tmpan@ntu.edu.tw [Department of Biochemical Science and Technology, College of Life Science, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan (China)

    2013-11-01

    Methylglyoxal (MG) is a toxic-glucose metabolite and a major precursor of advanced glycation endproducts (AGEs). MG has been reported to result in inflammation by activating receptor for AGEs (RAGE). We recently found that Monascus-fermented metabolite monascin acts as a novel natural peroxisome proliferator-activated receptor-γ (PPARγ) agonist that improves insulin sensitivity. We investigated the metabolic, biochemical, and molecular abnormalities characteristic of type 2 diabetes in MG-treated Wistar rats treated with oral administration of monascin or rosiglitazone. Monascin (a novel PPARγ agonist) activated nuclear factor-erythroid 2-related factor 2 (Nrf2) and down-regulated hyperinsulinmia in oral glucose tolerance test (OGTT). Monascin was able to elevate glyoxalase-1 expression via activation of hepatic Nrf2, hence, resulting in MG metabolism to D-lactic acid and protected from AGEs production in MG-treated rats. Rosiglitazone did not activate Nrf2 nor glyoxalase expression to lower serum and hepatic AGEs levels. Monascin acts as a novel natural Nrf2 activator with PPARγ-agonist activity were confirmed by Nrf2 and PPARγ reporter assays in Hep G2 cells. These findings suggest that monascin acts as an anti-diabetic and anti-oxidative stress agent to a greater degree than rosiglitazone and thus may have therapeutic potential for the prevention of diabetes. - Highlights: • Monascin acts as a PPARgamma agonist. • Monascin activates Nrf2 and AMPK. • Monascin promotes MG metabolism into D-lactic acid. • Monascin attenuates inflammation and diabetes in vivo.

  7. Nutrition and physical activity program to attenuate obesity and promote physical and metabolic fitness in elementary school children.

    Science.gov (United States)

    Donnelly, J E; Jacobsen, D J; Whatley, J E; Hill, J O; Swift, L L; Cherrington, A; Polk, B; Tran, Z V; Reed, G

    1996-05-01

    Obesity and low levels of physical and metabolic fitness are risk factors for cardiovascular disease and diabetes. The purpose of this investigation was to attenuate obesity and improve physical and metabolic fitness in elementary school children. Schools have the opportunity, mechanisms, and personnel in place to deliver nutrition education, fitness activities, and a school food service that is nutritious and healthy. Cohorts from grades 3 to 5 in two school districts in rural Nebraska (Intervention/Control) participated in a 2-year study of physical activity and modified school lunch program. Data collection for aerobic capacity, body composition, blood chemistry, nutrition knowledge, energy intake, and physical activity was at the beginning and end of each year. Int received enhanced physical activity, grade specific nutrition education, and a lower fat and sodium school lunch program. Con continued with a regular school lunch and team sports activity program. At year 2, Int lunches had significantly less energy (9%), fat (25%), sodium (21%), and more fiber (17%). However, measures of 24-hour energy intake for Int and Con showed significant differences for sodium only. Physical activity in the classroom was 6% greater for Int compared to Con (p < 0.05) but physical activity outside of school was approximately 16% less for Int compared to Con (p < 0.05). Body weight and body fat were not different between schools for normal weight or obese children. No differences were found for cholesterol, insulin, and glucose; however, HDL cholesterol was significantly greater and cholesterol/HDL was significantly less for Int compared to Con (p < 0.05). It appears that compensation in both energy intake and physical activity outside of school may be responsible for the lack of differences between Int and Con. PMID:8732957

  8. Benzyl isothiocyanate inhibits inflammasome activation in E. coli LPS-stimulated BV2 cells.

    Science.gov (United States)

    Lee, Chang-Min; Lee, Dae-Sung; Jung, Won-Kyo; Yoo, Jong Su; Yim, Mi-Jin; Choi, Yung Hyun; Park, Saegwang; Seo, Su-Kil; Choi, Jung Sik; Lee, Young-Min; Park, Won Sun; Choi, Il-Whan

    2016-09-01

    Inflammasomes are multi-protein complexes that play a crucial role in innate immune responses. Benzyl isothiocyanate (BITC) is a naturally occurring compound found in cruciferous vegetables, and BITC exhibits potential as a chemopreventive agent. However, whether BITC exerts inflammasome-mediated regulatory effects on neuroinflammation is unknown. In this study, we examined the effects of BITC on inflammasome-mediated interleukin-1β (IL-1β) production in E. coli lipopolysaccharide (LPS)-stimulated BV2 microglial cells. IL-1β production is tightly regulated at the post-translational level through the inflammasoume. We measured the levels of IL-1β produced from the LPS-exposed BV2 microglial cells using enzyme-linked immunosorbent assays (ELISAs). The BITC regulatory mechanisms in inflammasome-mediated cellular signaling pathways were examined by RT-PCR, western blot analysis and electrophoretic mobility shift assays. BITC inhibited the secretion of IL-1β induced by LPS in the BV2 microglial cells. BITC inhibited inflammasome activation and NLR family, pyrin domain containing 3 (NLRP3)-mediated caspase-1 activation, and decreased the levels of inflammasome activation pro-inflammatory mediators, including mitochondrial reactive oxygen species (ROS) and adenosine triphosphate (ATP) secretion in the LPS-stimulated BV2 microglial cells. Furthermore, we demonstrated that nuclear factor-κB (NF-κB) activation induced by LPS was inhibited by BITC, which may contribute to the attenuated secretion of IL-1β. These BITC-mediated inhibitory effects on IL-1β expression may thus regulate neuroinflammation through the inflammasome-mediated signaling pathway. PMID:27430883

  9. A 2-wk reduction of ambulatory activity attenuates peripheral insulin sensitivity

    DEFF Research Database (Denmark)

    Krogh-Madsen, Rikke; Thyfault, John P; Broholm, Christa;

    2010-01-01

    US adults take between approximately 2,000 and approximately 12,000 steps per day, a wide range of ambulatory activity that at the low range could increase risk for developing chronic metabolic diseases. Dramatic reductions in physical activity induce insulin resistance; however, it is uncertain...... possible biological cause for the public health problem of Type 2 diabetes has been identified. Reduced ambulatory activity for 2 wk in healthy, nonexercising young men significantly reduced peripheral insulin sensitivity, cardiovascular fitness, and lean leg mass....... if and how low ambulatory activity would influence peripheral insulin sensitivity. We aimed to explore if healthy, nonexercising subjects who went from a normal to a low level of ambulatory activity for 2 wk would display metabolic alterations including reduced peripheral insulin sensitivity. To do this, ten...

  10. Janus-faced microglia: beneficial and detrimental consequences of microglial phagocytosis

    Directory of Open Access Journals (Sweden)

    Amanda eSierra

    2013-01-01

    Full Text Available Microglia are the resident brain macrophages and they have been traditionally studied as orchestrators of the brain inflammatory response during infections and disease. In addition, microglia has a more benign, less explored role as the brain professional phagocytes. Phagocytosis is a term coined from the Greek to describe the receptor-mediated engulfment and degradation of dead cells and microbes. In addition, microglia phagocytoses brain-specific cargo, such as axonal and myelin debris in spinal cord injury or multiple sclerosis, amyloid-beta deposits in Alzheimer’s disease, and supernumerary synapses in postnatal development. Common mechanisms of recognition, engulfment and degradation of the different types of cargo are assumed, but very little is known about the shared and specific molecules involved in the phagocytosis of each target by microglia. More importantly, the functional consequences of microglial phagocytosis remain largely unexplored. Overall, phagocytosis is considered a beneficial phenomenon, since it eliminates dead cells and induces an anti-inflammatory response. However, phagocytosis can also activate the respiratory burst, which produces toxic reactive oxygen species. Phagocytosis has been traditionally studied in pathological conditions, leading to the assumption that microglia have to be activated in order to become efficient phagocytes. Recent data, however, has shown that unchallenged microglia phagocytose apoptotic cells during development and in adult neurogenic niches, suggesting an overlooked role in brain remodeling throughout the normal lifespan. The present review will summarize the current state of the literature regarding the role of microglial phagocytosis in maintaining tissue homeostasis in health as in disease.

  11. Hormetic Effect of Berberine Attenuates the Anticancer Activity of Chemotherapeutic Agents

    OpenAIRE

    Jiaolin Bao; Borong Huang; Lidi Zou; Shenghui Chen; Chao Zhang; Yulin Zhang; Meiwan Chen; Jian-Bo Wan; Huanxing Su; Yitao Wang; Chengwei He

    2015-01-01

    Hormesis is a phenomenon of biphasic dose response characterized by exhibiting stimulatory or beneficial effects at low doses and inhibitory or toxic effects at high doses. Increasing numbers of chemicals of various types have been shown to induce apparent hormetic effect on cancer cells. However, the underlying significance and mechanisms remain to be elucidated. Berberine, one of the major active components of Rhizoma coptidis, has been manifested with notable anticancer activities. This st...

  12. Palladium and platinum nanoparticles attenuate aging-like skin atrophy via antioxidant activity in mice.

    Directory of Open Access Journals (Sweden)

    Shuichi Shibuya

    Full Text Available Cu-Zn superoxide dismutase (Sod1 loss causes a redox imbalance as it leads to excess superoxide generation, which results in the appearance of various aging-related phenotypes, including skin atrophy. Noble metal nanoparticles, such as palladium (Pd and platinum (Pt nanoparticles, are considered to function as antioxidants due to their strong catalytic activity. In Japan, a mixture of Pd and Pt nanoparticles called PAPLAL has been used to treat chronic diseases over the past 60 years. In the present study, we investigated the protective effects of PAPLAL against aging-related skin pathologies in mice. Transdermal PAPLAL treatment reversed skin thinning associated with increased lipid peroxidation in Sod1-/- mice. Furthermore, PAPLAL normalized the gene expression levels of Col1a1, Mmp2, Has2, Tnf-α, Il-6, and p53 in the skin of the Sod1-/- mice. Pt nanoparticles exhibited marked SOD and catalase activity, while Pd nanoparticles only displayed weak SOD and catalase activity in vitro. Although the SOD and catalase activity of the Pt nanoparticles significantly declined after they had been oxidized in air, a mixture of Pd and Pt nanoparticles continued to exhibit SOD and catalase activity after oxidation. Importantly, a mixture of Pd and Pt nanoparticles with a molar ratio of 3 or 4 to 1 continued to exhibit SOD and catalase activity after oxidation, indicating that Pd nanoparticles prevent the oxidative deterioration of Pt nanoparticles. These findings indicate that PAPLAL stably suppresses intrinsic superoxide generation both in vivo and in vitro via SOD and catalase activity. PAPLAL is a potentially powerful tool for the treatment of aging-related skin diseases caused by oxidative damage.

  13. Palladium and platinum nanoparticles attenuate aging-like skin atrophy via antioxidant activity in mice.

    Science.gov (United States)

    Shibuya, Shuichi; Ozawa, Yusuke; Watanabe, Kenji; Izuo, Naotaka; Toda, Toshihiko; Yokote, Koutaro; Shimizu, Takahiko

    2014-01-01

    Cu-Zn superoxide dismutase (Sod1) loss causes a redox imbalance as it leads to excess superoxide generation, which results in the appearance of various aging-related phenotypes, including skin atrophy. Noble metal nanoparticles, such as palladium (Pd) and platinum (Pt) nanoparticles, are considered to function as antioxidants due to their strong catalytic activity. In Japan, a mixture of Pd and Pt nanoparticles called PAPLAL has been used to treat chronic diseases over the past 60 years. In the present study, we investigated the protective effects of PAPLAL against aging-related skin pathologies in mice. Transdermal PAPLAL treatment reversed skin thinning associated with increased lipid peroxidation in Sod1-/- mice. Furthermore, PAPLAL normalized the gene expression levels of Col1a1, Mmp2, Has2, Tnf-α, Il-6, and p53 in the skin of the Sod1-/- mice. Pt nanoparticles exhibited marked SOD and catalase activity, while Pd nanoparticles only displayed weak SOD and catalase activity in vitro. Although the SOD and catalase activity of the Pt nanoparticles significantly declined after they had been oxidized in air, a mixture of Pd and Pt nanoparticles continued to exhibit SOD and catalase activity after oxidation. Importantly, a mixture of Pd and Pt nanoparticles with a molar ratio of 3 or 4 to 1 continued to exhibit SOD and catalase activity after oxidation, indicating that Pd nanoparticles prevent the oxidative deterioration of Pt nanoparticles. These findings indicate that PAPLAL stably suppresses intrinsic superoxide generation both in vivo and in vitro via SOD and catalase activity. PAPLAL is a potentially powerful tool for the treatment of aging-related skin diseases caused by oxidative damage.

  14. Cocaine dependent individuals with attenuated striatal activation during reinforcement learning are more susceptible to relapse.

    Science.gov (United States)

    Stewart, Jennifer L; Connolly, Colm G; May, April C; Tapert, Susan F; Wittmann, Marc; Paulus, Martin P

    2014-08-30

    Cocaine-dependent individuals show altered brain activation during decision making. It is unclear, however, whether these activation differences are related to relapse vulnerability. This study tested the hypothesis that brain-activation patterns during reinforcement learning are linked to relapse 1 year later in individuals entering treatment for cocaine dependence. Subjects performed a Paper-Scissors-Rock task during functional magnetic resonance imaging (fMRI). A year later, we examined whether subjects had remained abstinent (n=15) or relapsed (n=15). Although the groups did not differ on demographic characteristics, behavioral performance, or lifetime substance use, abstinent patients reported greater motivation to win than relapsed patients. The fMRI results indicated that compared with abstinent individuals, relapsed users exhibited lower activation in (1) bilateral inferior frontal gyrus and striatum during decision making more generally; and (2) bilateral middle frontal gyrus and anterior insula during reward contingency learning in particular. Moreover, whereas abstinent patients exhibited greater left middle frontal and striatal activation to wins than losses, relapsed users did not demonstrate modulation in these regions as a function of outcome valence. Thus, individuals at high risk for relapse relative to those who are able to abstain allocate fewer neural resources to action-outcome contingency formation and decision making, as well as having less motivation to win on a laboratory-based task.

  15. Inhibition of Neuroinflammation in LPS-Activated Microglia by Cryptolepine

    Directory of Open Access Journals (Sweden)

    Olumayokun A. Olajide

    2013-01-01

    Full Text Available Cryptolepine, an indoloquinoline alkaloid in Cryptolepis sanguinolenta, has anti-inflammatory property. In this study, we aimed to evaluate the effects of cryptolepine on lipopolysaccharide (LPS- induced neuroinflammation in rat microglia and its potential mechanisms. Microglial activation was induced by stimulation with LPS, and the effects of cryptolepine pretreatment on microglial activation and production of proinflammatory mediators, PGE2/COX-2, microsomal prostaglandin E2 synthase and nitric oxide/iNOS were investigated. We further elucidated the role of Nuclear Factor-kappa B (NF-κB and the mitogen-activated protein kinases in the antiinflammatory actions of cryptolepine in LPS-stimulated microglia. Our results showed that cryptolepine significantly inhibited LPS-induced production of tumour necrosis factor-alpha (TNFα, interleukin-6 (IL-6, interleukin-1beta (IL-1β, nitric oxide, and PGE2. Protein and mRNA levels of COX-2 and iNOS were also attenuated by cryptolepine. Further experiments on intracellular signalling mechanisms show that IκB-independent inhibition of NF-κB nuclear translocation contributes to the anti-neuroinflammatory actions of cryptolepine. Results also show that cryptolepine inhibited LPS-induced p38 and MAPKAPK2 phosphorylation in the microglia. Cell viability experiments revealed that cryptolepine (2.5 and 5 μM did not produce cytotoxicity in microglia. Taken together, our results suggest that cryptolepine inhibits LPS-induced microglial inflammation by partial targeting of NF-κB signalling and attenuation of p38/MAPKAPK2.

  16. Activation of farnesoid X receptor downregulates visfatin and attenuates diabetic nephropathy.

    Science.gov (United States)

    Zhou, Baoshang; Feng, Bing; Qin, Zhexue; Zhao, Youguang; Chen, Yu; Shi, Zhengmin; Gong, Yi; Zhang, Jing; Yuan, Fahuan; Mu, Jiao

    2016-01-01

    Visfatin, a recently discovered adipocytokine, has been shown to have an important role in the pathogenesis of diabetic nephropathy (DN). The farnesoid X receptor (FXR), a ligand-activated nuclear receptor, plays a protective role in DN. The regulation between FXR and visfatin and their interaction in DN has not been well established. In this study, we reported that FXR agonist GW4064 reduced high glucose induced human mesangial cells (HMCs) inflammation, fibrosis and proliferation by downregulating visfatin expression, which can be blunted by exogenous visfatin treatment. Moreover, luciferase reporter assay showed FXR regulated visfatin transcription activity probably by binding to the -1607 bp and -1192 bp region of the visfatin promoter. In vivo study also showed that GW4064 ameliorated the progression of DN in db/db mice with a decreased visfatin expression. These findings suggest that FXR activation delayed the progression of diabetic nephropathy and this effect is through downregulating visfatin. PMID:26450152

  17. A two-week reduction of ambulatory activity attenuates peripheral insulin sensitivity

    DEFF Research Database (Denmark)

    Krogh-Madsen, Rikke; Thyfault, John P; Broholm, Christa;

    2009-01-01

    activity would influence peripheral insulin sensitivity. We aimed to explore if healthy, non-exercising subjects who went from a normal to a low level of ambulatory activity for two weeks would display metabolic alterations including reduced peripheral insulin sensitivity. -To do this, ten healthy young...... number of daily steps induced a significant reduction of 17% in the glucose infusion rate (GIR) during the clamp. This reduction was due to a decline in peripheral insulin sensitivity with no effect on hepatic endogenous glucose production. The insulin-stimulated ratio of pAkt(thr308)/total Akt decreased...... possible biological cause for the public health problem of type 2 diabetes has been identified. Reduced ambulatory activity for two weeks in healthy, non-exercising young men significantly reduced peripheral insulin sensitivity, cardiovascular fitness, and lean leg mass. Key words: Inactivity, Insulin...

  18. Microglial AGE-albumin is critical for neuronal death in Parkinson's disease: a possible implication for theranostics

    Directory of Open Access Journals (Sweden)

    Bayarsaikhan E

    2016-08-01

    Full Text Available Enkhjargal Bayarsaikhan,1,2,* Delger Bayarsaikhan,1,* Jaesuk Lee,1 Myeongjoo Son,1,3 Seyeon Oh,1 Jeongsik Moon,1 Hye-Jeong Park,1 Arivazhagan Roshini,1 Seung U Kim,4 Byoung-Joon Song,5 Seung-Mook Jo,6 Kyunghee Byun,1,3 Bonghee Lee1,3 1Center for Regenerative Medicine, Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon, Republic of Korea; 2Department of General Laboratory, National Cancer Center of Mongolia, Ulaanbaatar, Mongolia; 3Department of Anatomy and Cell Biology, Graduate School of Medicine, Gachon University, Incheon, Republic of Korea; 4Department of Medicine, University of British Columbia, Vancouver, Canada; 5Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD, USA; 6Department of Emergency Medical Services, Eulji University, Seongnam-si, Gyeonggi-do, Republic of Korea *These authors contributed equally to this work Abstract: Advanced glycation end products (AGEs are known to play an important role in the pathogenesis of neurodegenerative diseases, including Parkinson’s disease (PD, by inducing protein aggregation and cross-link, formation of Lewy body, and neuronal death. In this study, we observed that AGE-albumin, the most abundant AGE product in the human PD brain, is synthesized in activated microglial cells and accumulates in the extracellular space. AGE-albumin synthesis in human-activated microglial cells is distinctly inhibited by ascorbic acid and cytochalasin treatment. Accumulated AGE-albumin upregulates the receptor to AGE, leading to apoptosis of human primary dopamine (DA neurons. In animal experiments, we observed reduced DA neuronal cell death by treatment with soluble receptor to AGE. Our study provides evidence that activated microglial cells are one of the main contributors in AGE-albumin accumulation, deleterious to DA neurons in human and animal PD brains. Finally, activated microglial AGE

  19. Does a physically active lifestyle attenuate decline in all cognitive functions in old age?

    Science.gov (United States)

    Ballesteros, Soledad; Mayas, Julia; Reales, Jose Manuel

    2013-07-01

    In this study, the performance of a group of 20 physically active older adults was compared with that of a group of 20 sedentary healthy older adults while performing a series of cognitive tasks. These tasks were designed to assess processes that deteriorate most with age, namely executive control (assessed with the Wisconsin Card Sorting Task) and processing speed (simple and choice reaction time tasks). A repetition priming task that does not decline with age, involving attended and unattended picture outlines at encoding, was also included as a control task. The results show that a physically active lifestyle has a positive influence on executive control, processing speed, and controlled processing. As expected, a physically active lifestyle did not enhance repetition priming for attended stimuli, nor did it produce priming for unattended stimuli at encoding. Both groups exhibited robust priming for attended stimuli and no priming for unattended ones. Executive control functions are of vital importance for independent living in old age. These results have practical implications for enhancing the cognitive processes that decline most in old age. Promoting a physically active lifestyle throughout adulthood could significantly reduce the decline of effortful executive control functions in old age.

  20. Inhibition of classical complement activation attenuates liver ischaemia and reperfusion injury in a rat model

    NARCIS (Netherlands)

    B.H.M. Heijnen; I.H. Straatsburg; N.D. Padilla; G.J. Mierlo; C.E. Hack; T.M. van Gulik

    2006-01-01

    Activation of the complement system contributes to the pathogenesis of ischaemia/reperfusion (I/R) injury. We evaluated inhibition of the classical pathway of complement using C1-inhibitor (C1-inh) in a model of 70% partial liver I/R injury in male Wistar rats (n = 35). C1-inh was administered at 10

  1. Attenuated apoptosis response to Fas-ligand in active ulcerative colitis

    DEFF Research Database (Denmark)

    Seidelin, Jakob B; Nielsen, Ole H

    2008-01-01

    From mainly carcinoma cell line studies, apoptosis has been thought to play a major role in the pathogenesis of ulcerative colitis (UC). Apoptosis has been suggested to be due to a Fas ligand / Fas receptor interaction, but has never been studied in cells from patients with active UC. The aim...

  2. Attenuated apoptosis response to Fas-ligand in active ulcerative colitis

    DEFF Research Database (Denmark)

    Seidelin, J.B.; Nielsen, Ole Haagen

    2008-01-01

    BACKGROUND: From mainly carcinoma cell line studies, apoptosis has been thought to play a major role in the pathogenesis of ulcerative colitis (UC). Apoptosis has been suggested to be due to a Fas ligand / Fas receptor interaction, but has never been studied in cells from patients with active UC...

  3. Preconditioning of Carbon Monoxide Releasing Molecule-derived CO Attenuates LPS-induced Activation of HUVEC

    Directory of Open Access Journals (Sweden)

    Bingwei Sun, Xiangqian Zou, Yueling Chen, Ping Zhang, Gengsheng Shi

    2008-01-01

    Full Text Available Objective: To investigate the effects and potential mechanisms of preconditioning of tricarbonyldichlororuthenium (III dimer (CORM-2-liberated CO on LPS-induced activation of endothelial cells (HUVEC. Methods: HUVEC were pretreated with CORM-2 at the concentration of 50 or 100μM for 2 hrs, washed and stimulated with LPS (10μg/ml for additional 4 hrs. Activation (oxidative stress of HUVEC was assessed by measuring intracellular oxidation of DHR 123 or nitration of DAF-FM, specific H2O2 and NO fluorochromes, respectively. The expression of HO-1, iNOS (Western blot and ICAM-1 (cell ELISA proteins and activation of inflammation-relevant transcription factor, NF-κB (EMSA were assessed. In addition, PMN adhesion to HUVEC was also assessed. Results: The obtained data indicate that pretreatment of HUVEC with CORM-2 results in: 1 decrease of LPS-induced production of ROS and NO; 2 up-regulation of HO-1 but decrease in iNOS at the protein levels; 3 inhibition of LPS-induced activation of NF-κB; and 4 downregulation of expression of ICAM-1, and this was accompanied by a decrease of PMN adhesion to LPS-stimulated HUVEC. Conclusions: Preconditioning of CO liberated by CORM-2 elicited its anti-inflammatory effects by interfering with the induction of intracellular oxidative stress. In addition, it also supports the notion that CO is a potent inhibitor of iNOS and NF-κB.

  4. Recombinant activated protein C attenuates coagulopathy and inflammation when administered early in murine pneumococcal pneumonia

    NARCIS (Netherlands)

    M. Schouten; C. van 't Veer; J.J.T.H. Roelofs; B. Gerlitz; B.W. Grinnell; M. Levi; T. van der Poll

    2011-01-01

    Recombinant human activated protein C (APC), which has both anticoagulant and anti-inflammatory properties, improves survival of patients with severe sepsis. This beneficial effect is especially apparent in patients with pneumococcal pneumonia. Earlier treatment with APC in sepsis has been associate

  5. Imaging Striatal Microglial Activation in Patients with Parkinson's Disease.

    Directory of Open Access Journals (Sweden)

    Yuko Koshimori

    Full Text Available This study investigated whether the second-generation translocator protein 18kDa (TSPO radioligand, [18F]-FEPPA, could be used in neurodegenerative parkinsonian disorders as a biomarker for detecting neuroinflammation in the striatum. Neuroinflammation has been implicated as a potential mechanism for the progression of Parkinson's disease (PD. Positron Emission Tomography (PET radioligand targeting for TSPO allows for the quantification of neuroinflammation in vivo. Based on genotype of the rs6791 polymorphism in the TSPO gene, 16 mixed-affinity binders (MABs (8 PD and age-matched 8 healthy controls (HCs, 16 high-affinity binders (HABs (8 PD and age-matched 8 HCs and 4 low-affinity binders (LABs (3 PD and 1 HCs were identified. Total distribution volume (VT values in the striatum were derived from a two-tissue compartment model with arterial plasma as an input function. There was a significant main effect of genotype on [18F]-FEPPA VT values in the caudate nucleus (p = 0.001 and putamen (p < 0.001, but no main effect of disease or disease x genotype interaction in either ROI. In the HAB group, the percentage difference between PD and HC was 16% in both caudate nucleus and putamen; in the MAB group, it was -8% and 3%, respectively. While this PET study showed no evidence of increased striatal TSPO expression in PD patients, the current findings provide some insights on the possible interactions between rs6791 polymorphism and neuroinflammation in PD.

  6. Valproate Attenuates Nitroglycerin-Induced Trigeminovascular Activation by Preserving Mitochondrial Function in a Rat Model of Migraine

    Science.gov (United States)

    Li, Ruxian; Liu, Yushuang; Chen, Nan; Zhang, Yitong; Song, Ge; Zhang, Zhongling

    2016-01-01

    Background Migraine is a chronic disease that interferes with life quality and work productivity. Valproate shows protective effects against migraine, yet the underlying mechanisms are unclear. This study aimed to evaluate the potential effect of valproate on migraine using a rat model of nitroglycerin-induced trigeminovascular activation, as well as to explore the underlying mechanism. Material/Methods Intraperitoneal injection of nitroglycerin was conducted to induce trigeminovascular activation in rats. To explore the protective effect of valproate, a low dose (100 mg/kg) or a high dose (200 mg/kg) of valproate was intraperitoneally injected into rats, and then the levels of 5-hydroxytryptamine and nitric oxide in the peripheral blood were examined. The mtDNA copy number and the protein levels of peroxisome proliferator-activated receptor-γ coactivator 1α, mitochondrial transcription factor A, and peroxisome proliferator-activated receptor-γ in the spinal trigeminal nucleus were detected to evaluate the biogenesis of mitochondria. The mitochondrial energy metabolism was determined by the mitochondrial membrane potential and the levels of adenosine triphosphate, cytochrome C oxidase, and reactive oxygen species. Results Valproate attenuated nitroglycerin-induced trigeminovascular activation in rats, with reduced scratching behavior and restored 5-hydroxytryptamine and nitric oxide levels. Moreover, the mitochondrial energy metabolism and the biogenesis of mitochondria were preserved by valproate in nitroglycerin-treated rats. Conclusions The protective effect of valproate against migraine may be achieved through the modulation of mitochondrial biogenesis and function. Our study provides evidence for the potential use of valproate in the treatment of migraine. PMID:27618395

  7. Mixed disulfide formation at Cys141 leads to apparent unidirectional attenuation of Aspergillus niger NADP-glutamate dehydrogenase activity.

    Directory of Open Access Journals (Sweden)

    Adhish S Walvekar

    Full Text Available NADP-Glutamate dehydrogenase from Aspergillus niger (AnGDH exhibits sigmoid 2-oxoglutarate saturation. Incubation with 2-hydroxyethyl disulfide (2-HED, the disulfide of 2-mercaptoethanol resulted in preferential attenuation of AnGDH reductive amination (forward activity but with a negligible effect on oxidative deamination (reverse activity, when monitored in the described standard assay. Such a disulfide modified AnGDH displaying less than 1.0% forward reaction rate could be isolated after 2-HED treatment. This unique forward inhibited GDH form (FIGDH, resembling a hypothetical 'one-way' active enzyme, was characterized. Kinetics of 2-HED mediated inhibition and protein thiol titrations suggested that a single thiol group is modified in FIGDH. Two site-directed cysteine mutants, C141S and C415S, were constructed to identify the relevant thiol in FIGDH. The forward activity of C141S alone was insensitive to 2-HED, implicating Cys141 in FIGDH formation. It was observed that FIGDH displayed maximal reaction rate only after a pre-incubation with 2-oxoglutarate and NADPH. In addition, compared to the native enzyme, FIGDH showed a four fold increase in K0.5 for 2-oxoglutarate and a two fold increase in the Michaelis constants for ammonium and NADPH. With no change in the GDH reaction equilibrium constant, the FIGDH catalyzed rate of approach to equilibrium from reductive amination side was sluggish. Altered kinetic properties of FIGDH at least partly account for the observed apparent loss of forward activity when monitored under defined assay conditions. In sum, although Cys141 is catalytically not essential, its covalent modification provides a striking example of converting the biosynthetic AnGDH into a catabolic enzyme.

  8. Sinomenine induces the generation of intestinal Treg cells and attenuates arthritis via activation of aryl hydrocarbon receptor.

    Science.gov (United States)

    Tong, Bei; Yuan, Xusheng; Dou, Yannong; Wu, Xin; Wang, Yuhui; Xia, Yufeng; Dai, Yue

    2016-10-01

    Sinomenine (SIN), an anti-arthritis drug, has previously been proven to exert immunomodulatory activity in rats by inducing intestinal regulatory T-cells (Treg cells). Here, we assessed the effect of SIN on the generation and function of Treg cells in autoimmune arthritis, and the underlying mechanisms in view of aryl hydrocarbon receptor (AhR). The proportions of Treg cells and IL-17-producing T-cells (Th17 cells) differentiated from naive T-cells were analyzed by flow cytometric analysis. The AhR agonistic effect of SIN was tested by analyzing the activation of downstream signaling pathways and target genes. The dependence of intestinal Treg cell induction and arthritis alleviation by SIN on AhR activation was confirmed in a mouse collagen-induced arthritis (CIA) model. SIN promoted the differentiation and function of intestinal Treg cells in vitro. It induced the expression and activity of AhR target gene, promoted AhR/Hsp90 dissociation and AhR nuclear translocation, induced XRE reporter activity, and facilitated AhR/XRE binding in vitro, displaying the potential to be an agonist of AhR. In CIA mice, SIN induced the generation of intestinal Treg cells, and facilitated the immunosuppressive function of these Treg cells as shown by an adoptive transfer test. In addition, the induction of intestinal Treg cells and the anti-arthritic effect of SIN in CIA mice could be largely diminished by the AhR antagonist resveratrol. SIN attenuates arthritis by promoting the generation and function of Treg cells in an AhR-dependent manner. PMID:27617398

  9. Acupuncture Attenuated Inflammation and Inhibited Th17 and Treg Activity in Experimental Asthma

    OpenAIRE

    Ying Wei; Ming Dong; Hongying Zhang; Yubao Lv; Jiaqi Liu; Kai Wei; Qingli Luo; Jing Sun; Feng Liu; Fei Xu; Jingcheng Dong

    2015-01-01

    Acupuncture is an effective therapeutic method in asthma treatment in traditional Chinese medicine. Here, we evaluated the effect of acupuncture on airway hyperresponsiveness (AHR) and the associated inflammatory changes as well as Th17 and Treg activity in ovalbumin- (OVA-) induced experimental asthma. Our results revealed that acupuncture treatment significantly inhibited AHR, lung inflammation, and mucus secretion of experimental asthma mice. Furthermore, a decrease in lymphocytes and eosi...

  10. Faulty Suppression of Irrelevant Material in Patients with Thought Disorder Linked to Attenuated Frontotemporal Activation

    OpenAIRE

    Arcuri, S. M.; Broome, M. R.; Giampietro, V.; Amaro, E; T. T. J. Kircher; Williams, S.C.R.; Andrew, C. M.; Brammer, M.; Morris, R. G.; McGuire, P. K.

    2012-01-01

    Formal thought disorder is a feature schizophrenia that manifests as disorganized, incoherent speech, and is associated with a poor clinical outcome. The neurocognitive basis of this symptom is unclear but it is thought to involve an impairment in semantic processing classically described as a loosening of meaningful associations. Using a paradigm derived from the n400 event-related, potential, we examined the extent to which regional activation during semantic processing is altered in schizo...

  11. Loss of CARD9-mediated innate activation attenuates severe influenza pneumonia without compromising host viral immunity

    OpenAIRE

    Takayuki Uematsu; Ei’ichi Iizasa; Noritada Kobayashi; Hiroki Yoshida; Hiromitsu Hara

    2015-01-01

    Influenza virus (IFV) infection is a common cause of severe viral pneumonia associated with acute respiratory distress syndrome (ARDS), which is difficult to control with general immunosuppressive therapy including corticosteroids due to the unfavorable effect on viral replication. Studies have suggested that the excessive activation of the innate immunity by IFV is responsible for severe pathologies. In this study, we focused on CARD9, a signaling adaptor known to regulate innate immune acti...

  12. 17β-estradiol attenuates injury-induced microglia activation in the oculomotor nucleus.

    Science.gov (United States)

    Gyenes, A; Hoyk, Z; Csakvari, E; Siklos, L; Parducz, A

    2010-12-15

    Recent studies provide increasing data indicating the prominent role of estrogens in protecting the nervous system against the noxious consequences of nerve injury. It is also clear that in the process of nerve injury and recovery not only the neurons, but the glial cells are also involved and they are important components of the protective mechanisms. In the present article the effect of 17β-estradiol on injury-induced microglia activation was studied in an animal model. Peripheral axotomy of the oculomotor neurons was achieved by the removal of the right eyeball including the extraocular muscles of ovariectomized adult mice. The time course and the extent of microglia activation was followed by the unbiased morphometric analysis of CD11b immunoreactive structures within the oculomotor nucleus. The first sign of microglia activation appeared after 24 h following injury, the maximal effect was found on the fourth day. In ovariectomized females hormone treatment (daily injection of 17β-estradiol, 5 μg/100 g b.w.) decreased significantly the microglia reaction at postoperative day 4. Our results show that microglia response to nerve injury is affected by estradiol, that is these cells may mediate some of the hormonal effects and may contribute to protective mechanisms resulting in the structural and functional recovery of the nervous system. PMID:20870014

  13. Activation of the adenosine A2A receptor attenuates experimental autoimmune encephalomyelitis and is associated with increased intracellular calcium levels.

    Science.gov (United States)

    Liu, Yumei; Zou, Haifeng; Zhao, Ping; Sun, Bo; Wang, Jinghua; Kong, Qingfei; Mu, Lili; Zhao, Sihan; Wang, Guangyou; Wang, Dandan; Zhang, Yao; Zhao, Jiaying; Yin, Pengqi; Liu, Lei; Zhao, Xiuli; Li, Hulun

    2016-08-25

    Multiple sclerosis (MS) is a common autoimmune disease that inevitably causes inflammatory nerve demyelination. However, an effective approach to prevent its course is still lacking and urgently needed. Recently, the adenosine A2A receptor (A2AR) has emerged as a novel inflammation regulator. Manipulation of A2AR activity may suppress the MS process and protect against nerve damage. To test this hypothesis, we treated murine experimental autoimmune encephalomyelitis (EAE), a model for MS, with the selective A2AR agonist, CGS21680 (CGS). We evaluated the effects of CGS on the pathological features of EAE progression, including CNS cellular infiltration, inflammatory cytokine expression, lymphocyte proliferation, and cell surface markers. Treatment with CGS significantly suppressed specific lymphocyte proliferation, reduced infiltration of CD4(+) T lymphocytes, and attenuated the expression of inflammatory cytokines, which in turn inhibited the EAE progression. For the first time, we demonstrate that CGS can increase the intracellular calcium concentration ([Ca(2+)]i) in murine lymphocytes, which may be the mechanism underlying the suppressive effects of CGS-induced A2AR activation on EAE progression. Our findings strongly suggest that A2AR is a potential therapeutic target for MS and provide insight into the mechanism of action of A2AR agonists, which may offer a therapeutic option for this disease. PMID:27217214

  14. Effects of the live attenuated measles-mumps-rubella booster vaccination on disease activity in patients with juvenile idiopathic arthritis : a randomized trial

    NARCIS (Netherlands)

    Heijstek, Marloes W; Kamphuis, Sylvia; Armbrust, Wineke; Swart, Joost; Gorter, Simone; de Vries, Lara D; Smits, Gaby P; van Gageldonk, Pieter G; Berbers, Guy A M; Wulffraat, Nico M

    2013-01-01

    IMPORTANCE: The immunogenicity and the effects of live attenuated measles-mumps-rubella (MMR) vaccination on disease activity in patients with juvenile idiopathic arthritis (JIA) are matters of concern, especially in patients treated with immunocompromising therapies. OBJECTIVES: To assess whether M

  15. Activation of the kinin B1 receptor attenuates melanoma tumor growth and metastasis.

    Directory of Open Access Journals (Sweden)

    Patricia Dillenburg-Pilla

    Full Text Available Melanoma is a very aggressive tumor that does not respond well to standard therapeutic approaches, such as radio- and chemotherapies. Furthermore, acquiring the ability to metastasize in melanoma and many other tumor types is directly related to incurable disease. The B1 kinin receptor participates in a variety of cancer-related pathophysiological events, such as inflammation and angiogenesis. Therefore, we investigated whether this G protein-coupled receptor plays a role in tumor progression. We used a murine melanoma cell line that expresses the kinin B1 receptor and does not express the kinin B2 receptor to investigate the precise contribution of activation of the B1 receptor in tumor progression and correlated events using various in vitro and in vivo approaches. Activation of the kinin B1 receptor in the absence of B2 receptor inhibits cell migration in vitro and decreases tumor formation in vivo. Moreover, tumors formed from cells stimulated with B1-specific agonist showed several features of decreased aggressiveness, such as smaller size and infiltration of inflammatory cells within the tumor area, higher levels of pro-inflammatory cytokines implicated in the host anti-tumor immune response, lower number of cells undergoing mitosis, a poorer vascular network, no signs of invasion of surrounding tissues or metastasis and increased animal survival. Our findings reveal that activation of the kinin B1 receptor has a host protective role during murine melanoma tumor progression, suggesting that the B1 receptor could be a new anti-tumor GPCR and provide new opportunities for therapeutic targeting.

  16. Novel matrine derivative MD-1 attenuates hepatic fibrosis by inhibiting EGFR activation of hepatic stellate cells.

    Science.gov (United States)

    Feng, Yi; Ying, Hai-Yan; Qu, Ying; Cai, Xiao-Bo; Xu, Ming-Yi; Lu, Lun-Gen

    2016-09-01

    Matrine (MT), the effective component of Sophora flavescens Ait, has been shown to have anti-inflammation, immune-suppressive, anti-tumor, and anti-hepatic fibrosis activities. However, the pharmacological effects of MT still need to be strengthened due to its relatively low efficacy and short half-life. In the present study, we report a more effective thio derivative of MT, MD-1, and its inhibitory effects on the activation of hepatic stellate cells (HSCs) in both cell culture and animal models. Cytological experiments showed that MD-1 can inhibit the proliferation of HSC-T6 cells with a half-maximal inhibitory concentration (IC50) of 62 μmol/L. In addition, MD-1 more strongly inhibits the migration of HSC-T6 cells compared to MT and can more effectively induce G0/G1 arrest and apoptosis. Investigating the biological mechanisms underlying anti-hepatic fibrosis in the presence of MD-1, we found that MD-1 can bind the epidermal growth factor receptor (EGFR) on the surface of HSC-T6 cells, which can further inhibit the phosphorylation of EGFR and its downstream protein kinase B (Akt), resulting in decreased expression of cyclin D1 and eventual inhibition of the activation of HSC-T6 cells. Furthermore, in rats with dimethylnitrosamine (DMN)-induced hepatic fibrosis, MD-1 slowed the development and progression of hepatic fibrosis, protecting hepatic parenchymal cells and improving hepatic functions. Therefore, MD-1 is a potential drug for anti-hepatic fibrosis.

  17. Matrine attenuates focal cerebral ischemic injury by improving antioxidant activity and inhibiting apoptosis in mice.

    Science.gov (United States)

    Zhao, Peng; Zhou, Ru; Zhu, Xiao-Yun; Hao, Yin-Ju; Li, Nan; Wang, Jie; Niu, Yang; Sun, Tao; Li, Yu-Xiang; Yu, Jian-Qiang

    2015-09-01

    Matrine, an active constituent of the Chinese herb, Sophora flavescens Ait., and it is known for its antioxidant, anti-inflammatory and antitumor activities. It has been demonstrated that matrine exerts protective effects against heart failure by decreasing the expression of caspase-3 and Bax, and increasing Bcl‑2 levels. In this study, we aimed to determine whether these protective effects of matrine can be applied to cerebral ischemia. Following 7 successive days of treatment with matrine (7.5, 15 and 30 mg/kg) and nimodipine (1 mg/kg) by intraperitoneal injection, male Institute of Cancer Research (ICR) mice were subjected to middle cerebral artery occlusion (MCAO). Following reperfusion, the neurobehavioral score and brain infarct volume were estimated, and morphological changes were analyzed by hematoxylin and eosin (H&E) staining and electron microscopy. The percentage of apoptotic neurons was determined by flow cytometry. The levels of oxidative stress were assessed by measuring the levels of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT), and the total antioxidant capacity (T-AOC). Western blot analysis and immunofluorescence staining were used to examine the expression of the apoptosis-related proteins, caspase-3, Bax and Bcl-2. Our results revealed that pre-treatment with matrine significantly decreased the infarct volume and improved the neurological scores. Matrine also reduced the percentage of apoptotic neurons and relieved neuronal morphological damage. Furthermore, matrine markedly decreased the MDA levels, and increased SOD, GSH-Px and CAT activity, and T-AOC. Western blot analysis and immunofluorescence staining revealed a marked decrease in caspase-3 expression and an increase in the Bcl-2/Bax ratio in the group pre-treated with matrine (30 mg/kg) as compared with the vehicle-treated group. The findings of the present study demonstrate that matrine exerts neuroprotective effects against

  18. Faulty Suppression of Irrelevant Material in Patients with Thought Disorder Linked to Attenuated Frontotemporal Activation

    Directory of Open Access Journals (Sweden)

    S. M. Arcuri

    2012-01-01

    Full Text Available Formal thought disorder is a feature schizophrenia that manifests as disorganized, incoherent speech, and is associated with a poor clinical outcome. The neurocognitive basis of this symptom is unclear but it is thought to involve an impairment in semantic processing classically described as a loosening of meaningful associations. Using a paradigm derived from the n400 event-related, potential, we examined the extent to which regional activation during semantic processing is altered in schizophrenic patients with formal thought disorder. Ten healthy control and 18 schizophrenic participants (9 with and 9 without formal thought disorder performed a semantic decision sentence task during an event-related functional magnetic resonance imaging experiment. We employed analysis of variance to estimate the main effects of semantic congruency and groups on activation and specific effects of formal thought disorder were addressed using post-hoc comparisons. We found that the frontotemporal network, normally engaged by a semantic decision task, was underactivated in schizophrenia, particularly in patients with FTD. This network is implicated in the inhibition of automatically primed stimuli and impairment of its function interferes with language processing and contributes to the production of incoherent speech.

  19. Piperine, an active ingredient of black pepper attenuates acetaminophen-induced hepatotoxicity in mice

    Institute of Scientific and Technical Information of China (English)

    Evan Prince Sabina; Annie Deborah Harris Souriyan; Deborah Jackline; Mahaboob Khan Rasool

    2010-01-01

    Objective: To explore the hepatoprotective and antioxidant effects of piperine against acetaminophen-induced hepatotoxicity in mice. Methods: In mice, hepatotoxicity was induced by a single dose of acetaminophen (900 mg/kg b.w. i.p.). Piperine (25 mg/kg b.w. i.p.) and standard drug silymarin (25 mg/kg b.w. i.p.) were given to mice, 30 min after the single injection of acetaminophen. After 4 h, the mice were decapitated. Activities of liver marker enzymes [(aspartate transaminase (AST), alanine transaminase (ALT), and alkaline phosphatase (ALP)] and inflammatory mediator tumour necrosis factor-alpha (TNF-α) were estimated in serum, while lipid peroxidation and antioxidant status (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione-s-transferase and glutathione) were determined in liver homogenate of control and experimental mice. Results: Acetaminophen induction (900 mg/kg b.w. i.p.) significantly increased the levels of liver marker enzymes, TNF-α, and lipid peroxidation, and caused the depletion of antioxidant status. Piperine and silymarin treatment to acetaminophen challenged mice resulted in decreased liver marker enzymes activity, TNF-α and lipid peroxidation levels with increase in antioxidant status. Conclusions: The results clearly demonstrate that piperine shows promising hepatoprotective effect as comparable to standard drug silymarin.

  20. Acupuncture Attenuated Inflammation and Inhibited Th17 and Treg Activity in Experimental Asthma.

    Science.gov (United States)

    Wei, Ying; Dong, Ming; Zhang, Hongying; Lv, Yubao; Liu, Jiaqi; Wei, Kai; Luo, Qingli; Sun, Jing; Liu, Feng; Xu, Fei; Dong, Jingcheng

    2015-01-01

    Acupuncture is an effective therapeutic method in asthma treatment in traditional Chinese medicine. Here, we evaluated the effect of acupuncture on airway hyperresponsiveness (AHR) and the associated inflammatory changes as well as Th17 and Treg activity in ovalbumin- (OVA-) induced experimental asthma. Our results revealed that acupuncture treatment significantly inhibited AHR, lung inflammation, and mucus secretion of experimental asthma mice. Furthermore, a decrease in lymphocytes and eosinophils as well as neutrophils was observed in bronchoalveolar lavage fluid (BALF) of mice treated with acupuncture. Acupuncture reduced the OVA specific IgE level as well as the Th17 cytokine levels including IL-17A, IL-17F, and IL-22 in the serum of the experimental asthma mice. Acupuncture treatment group also had reduced CD4+IL-17A+ cell numbers and increased CD4+Foxp3+ cell numbers in BALF. In addition, acupuncture could inhibit IL-17R, RORγt, p65, and the inhibitor of NF-κB kinase-α (IKKα) protein expression. Our results indicated that acupuncture was effective in inhibiting AHR and inflammation in OVA-induced experimental asthma, which may be associated with the regulation of Th17 and Treg activity and NF-κB pathway. PMID:26612993

  1. Acupuncture Attenuated Inflammation and Inhibited Th17 and Treg Activity in Experimental Asthma

    Directory of Open Access Journals (Sweden)

    Ying Wei

    2015-01-01

    Full Text Available Acupuncture is an effective therapeutic method in asthma treatment in traditional Chinese medicine. Here, we evaluated the effect of acupuncture on airway hyperresponsiveness (AHR and the associated inflammatory changes as well as Th17 and Treg activity in ovalbumin- (OVA- induced experimental asthma. Our results revealed that acupuncture treatment significantly inhibited AHR, lung inflammation, and mucus secretion of experimental asthma mice. Furthermore, a decrease in lymphocytes and eosinophils as well as neutrophils was observed in bronchoalveolar lavage fluid (BALF of mice treated with acupuncture. Acupuncture reduced the OVA specific IgE level as well as the Th17 cytokine levels including IL-17A, IL-17F, and IL-22 in the serum of the experimental asthma mice. Acupuncture treatment group also had reduced CD4+IL-17A+ cell numbers and increased CD4+Foxp3+ cell numbers in BALF. In addition, acupuncture could inhibit IL-17R, RORγt, p65, and the inhibitor of NF-κB kinase-α (IKKα protein expression. Our results indicated that acupuncture was effective in inhibiting AHR and inflammation in OVA-induced experimental asthma, which may be associated with the regulation of Th17 and Treg activity and NF-κB pathway.

  2. Acupuncture Attenuated Inflammation and Inhibited Th17 and Treg Activity in Experimental Asthma

    Science.gov (United States)

    Wei, Ying; Dong, Ming; Zhang, Hongying; Lv, Yubao; Liu, Jiaqi; Wei, Kai; Luo, Qingli; Sun, Jing; Liu, Feng; Xu, Fei; Dong, Jingcheng

    2015-01-01

    Acupuncture is an effective therapeutic method in asthma treatment in traditional Chinese medicine. Here, we evaluated the effect of acupuncture on airway hyperresponsiveness (AHR) and the associated inflammatory changes as well as Th17 and Treg activity in ovalbumin- (OVA-) induced experimental asthma. Our results revealed that acupuncture treatment significantly inhibited AHR, lung inflammation, and mucus secretion of experimental asthma mice. Furthermore, a decrease in lymphocytes and eosinophils as well as neutrophils was observed in bronchoalveolar lavage fluid (BALF) of mice treated with acupuncture. Acupuncture reduced the OVA specific IgE level as well as the Th17 cytokine levels including IL-17A, IL-17F, and IL-22 in the serum of the experimental asthma mice. Acupuncture treatment group also had reduced CD4+IL-17A+ cell numbers and increased CD4+Foxp3+ cell numbers in BALF. In addition, acupuncture could inhibit IL-17R, RORγt, p65, and the inhibitor of NF-κB kinase-α (IKKα) protein expression. Our results indicated that acupuncture was effective in inhibiting AHR and inflammation in OVA-induced experimental asthma, which may be associated with the regulation of Th17 and Treg activity and NF-κB pathway. PMID:26612993

  3. Perindopril Attenuates Lipopolysaccharide-Induced Amyloidogenesis and Memory Impairment by Suppression of Oxidative Stress and RAGE Activation.

    Science.gov (United States)

    Goel, Ruby; Bhat, Shahnawaz Ali; Hanif, Kashif; Nath, Chandishwar; Shukla, Rakesh

    2016-02-17

    Clinical and preclinical studies account hypertension as a risk factor for dementia. We reported earlier that angiotensin-converting enzyme (ACE) inhibition attenuated the increased vulnerability to neurodegeneration in hypertension and prevented lipopolysaccharide (LPS)-induced memory impairment in normotensive wistar rats (NWRs) and spontaneously hypertensive rats (SHRs). Recently, a receptor for advanced glycation end products (RAGE) has been reported to induce amyloid beta (Aβ1-42) deposition and memory impairment in hypertensive animals. However, the involvement of ACE in RAGE activation and amyloidogenesis in the hypertensive state is still unexplored. Therefore, in this study, we investigated the role of ACE on RAGE activation and amyloidogenesis in memory-impaired NWRs and SHRs. Memory impairment was induced by repeated (on days 1, 4, 7, and 10) intracerebroventricular (ICV) injections of LPS in SHRs (25 μg) and NWRs (50 μg). Our data showed that SHRs exhibited increased oxidative stress (increased gp91-phox/NOX-2 expression and ROS generation), RAGE, and β-secretase (BACE) expression without Aβ1-42 deposition. LPS (25 μg, ICV) further amplified oxidative stress, RAGE, and BACE activation, culminating in Aβ1-42 deposition and memory impairment in SHRs. Similar changes were observed at the higher dose of LPS (50 μg, ICV) in NWRs. Further, LPS-induced oxidative stress was associated with endothelial dysfunction and reduction in cerebral blood flow (CBF), more prominently in SHRs than in NWRs. Finally, we showed that perindopril (0.1 mg/kg, 15 days) prevented memory impairment by reducing oxidative stress, RAGE activation, amyloidogenesis, and improved CBF in both SHRs and NWRs. These findings suggest that perindopril might be used as a therapeutic strategy for the early stage of dementia. PMID:26689453

  4. Modulation of Lipopolysaccharide Stimulated Nuclear Factor kappa B Mediated iNOS/NO Production by Bromelain in Rat Primary Microglial Cells

    OpenAIRE

    Abbasi Habashi, Soraya; Sabouni, Farzaneh; Moghimi, Ali; Ansari Majd, Saeed

    2016-01-01

    Background: Microglial cells act as the sentinel of the central nervous system .They are involved in neuroprotection but are highly implicated in neurodegeneration of the aging brain. When over-activated, microglia release pro-inflammatory factors, such as nitric oxide (NO) and cytokines, which are critical in eliciting neuroinflammatory responses associated with neurodegenerative diseases. This study examined whether bromelain, the pineapple-derived extract, may exert an anti-inflammatory ef...

  5. Activated farnesoid X receptor attenuates apoptosis and liver injury in autoimmune hepatitis.

    Science.gov (United States)

    Lian, Fan; Wang, Yu; Xiao, Youjun; Wu, Xiwen; Xu, Hanshi; Liang, Liuqin; Yang, Xiuyan

    2015-10-01

    Autoimmune hepatitis (AIH) is a chronic inflammatory liver disease associated with interface hepatitis, the presence of autoantibodies, regulatory T‑cell dysfunction and raised plasma liver enzyme levels. The present study assessed the hepatoprotective and antiapoptotic role of farnesoid X receptor (FXR) in AIH. a mouse model of AIH was induced by treatment with concanavalin A (ConA). The FXR agonist, chenodeoxycholic acid (CDCA), was administered to mice exhibiting ConA‑induced liver injury and a normal control. Blood samples were obtained to detect the levels of aminotransferases and inflammatory cytokines. Liver specimens were collected, and hematoxylin‑eosin staining was used for histopathological examination and detection. Apoptosis was evaluated using the terminal deoxynucleotidyl-transferase‑mediated dUTP nick end labeling (TUNEL) method. The expression levels of apoptosis‑associated genes and proteins were determined by reverse transcription‑quantitative polymerase chain reaction and western blotting, respectively. The results demonstrated that FXR was downregulated at the mRNA and protein level in the liver specimens of mice induced with ConA‑induced hepatitis. Increased levels of aminotransferases and inflammatory cytokines, including interferon‑γ, tumor necrosis factor‑α, interleukin (IL)‑4 and IL‑2, were detected in ConA‑treated mice. The mice pretreated with the FXR agonist, CDCA, were more resistant to ConA hepatitis, as indicated by reduced levels of alanine transaminase/aspartate aminotransferase and aminotransferases. The activation of FXR ameliorated hepatocyte apoptosis, as demonstrated by TUNEL analysis and downregulation of the Fas/Fas ligand, tumor necrosis factor‑related apoptosis‑inducing ligand and caspase‑3. Taken together, FXR activation ameliorated liver injury and suppressed inflammatory cytokines in ConA‑induced hepatitis. FXR, therefore, exerts a protective role against ConA-induced apoptosis. PMID

  6. Oral glucose ingestion attenuates exercise-induced activation of 5'-AMP-activated protein kinase in human skeletal muscle

    DEFF Research Database (Denmark)

    Åkerström, Thorbjörn; Birk, Jesper Bratz; Klein, Ditte Kjærsgaard;

    2006-01-01

    5'-AMP-activated protein kinase (AMPK) has been suggested to be a 'metabolic master switch' regulating various aspects of muscle glucose and fat metabolism. In isolated rat skeletal muscle, glucose suppresses the activity of AMPK and in human muscle glycogen loading decreases exercise-induced AMPK...

  7. Copper Ion Attenuated the Antiproliferative Activity of Di-2-pyridylhydrazone Dithiocarbamate Derivative; However, There Was a Lack of Correlation between ROS Generation and Antiproliferative Activity.

    Science.gov (United States)

    Wang, Tingting; Fu, Yun; Huang, Tengfei; Liu, Youxun; Wu, Meihao; Yuan, Yanbin; Li, Shaoshan; Li, Changzheng

    2016-01-01

    The use of chelators for cancer treatment has been an alternative option. Dithiocarbamates have recently attracted considerable attention owning to their diverse biological activities; thus, the preparation of new dithiocarbamate derivatives with improved antitumor activity and selectivity as well as probing the underlying molecular mechanism are required. In this study, di-2-pyridylhydrazone dithiocarbamate S-propionic acid (DpdtpA) and its copper complex were prepared and characterized, and its antiproliferative activity was evaluated. The proliferation inhibition assay showed that DpdtpA exhibited excellent antiproliferative effect in hepatocellular carcinoma (IC50 = 1.3 ± 0.3 μM for HepG2, and 2.5 ± 0.6 μM for Bel-7402). However, in the presence of copper ion, the antiproliferative activity of DpdtpA was dramatically attenuated (20-30 fold) owing to the formation of copper chelate. A preliminarily mechanistic study revealed that reactive oxygen species (ROS) generation mediated the antiproliferative activity of DpdtpA, and accordingly induced apoptosis, DNA cleavage, and autophagy. Surprisingly, the cytotoxicity of DpdtpA copper complex (DpdtpA-Cu) was also involved in ROS generation; however, a paradoxical relation between cellular ROS level and cytotoxicity was observed. Further investigation indicated that DpdtpA could induce cell cycle arrest at the S phase; however, DpdtpA-Cu lacked this effect, which explained the difference in their antiproliferative activity. PMID:27556432

  8. Copper Ion Attenuated the Antiproliferative Activity of Di-2-pyridylhydrazone Dithiocarbamate Derivative; However, There Was a Lack of Correlation between ROS Generation and Antiproliferative Activity

    Directory of Open Access Journals (Sweden)

    Tingting Wang

    2016-08-01

    Full Text Available The use of chelators for cancer treatment has been an alternative option. Dithiocarbamates have recently attracted considerable attention owning to their diverse biological activities; thus, the preparation of new dithiocarbamate derivatives with improved antitumor activity and selectivity as well as probing the underlying molecular mechanism are required. In this study, di-2-pyridylhydrazone dithiocarbamate S-propionic acid (DpdtpA and its copper complex were prepared and characterized, and its antiproliferative activity was evaluated. The proliferation inhibition assay showed that DpdtpA exhibited excellent antiproliferative effect in hepatocellular carcinoma (IC50 = 1.3 ± 0.3 μM for HepG2, and 2.5 ± 0.6 μM for Bel-7402. However, in the presence of copper ion, the antiproliferative activity of DpdtpA was dramatically attenuated (20–30 fold owing to the formation of copper chelate. A preliminarily mechanistic study revealed that reactive oxygen species (ROS generation mediated the antiproliferative activity of DpdtpA, and accordingly induced apoptosis, DNA cleavage, and autophagy. Surprisingly, the cytotoxicity of DpdtpA copper complex (DpdtpA–Cu was also involved in ROS generation; however, a paradoxical relation between cellular ROS level and cytotoxicity was observed. Further investigation indicated that DpdtpA could induce cell cycle arrest at the S phase; however, DpdtpA–Cu lacked this effect, which explained the difference in their antiproliferative activity.

  9. Linalool attenuates lung inflammation induced by Pasteurella multocida via activating Nrf-2 signaling pathway.

    Science.gov (United States)

    Wu, Qianchao; Yu, Lijun; Qiu, Jiaming; Shen, Bingyu; Wang, Di; Soromou, Lanan Wassy; Feng, Haihua

    2014-08-01

    Pasteurellosis caused by Pasteurella multocida manifest often as respiratory infection in farmed small ruminants. Although the incidence of pasteurellosis due to P. multocida mainly takes the form of pneumonia, there is limited information on host factors that play a role in disease pathogenesis in the milieu of host-pathogen interactions. Nuclear factor-erythroid 2 related factor 2 (Nrf-2), a critical regulator for various inflammatory and immune responses by controlling oxidative stress, may play an important role in the processes of inflammation induced by P. multocida. In this study, linalool, a natural compound of the essential oils in several aromatic plant species, elevated nuclear Nrf-2 protein translocation in the A549 lung cell line and in vivo. The P. multocida-induced pro-inflammatory cytokines expression was abrogated by Nrf-2 siRNA. Postponed treatment with linalool decreased lung neutrophil accumulation and enhanced clearance of P. multocida. Furthermore, linalool significantly increased the expression of antioxidant enzymes regulated by Nrf-2 and diminished lung tissue levels of several pro-inflammatory cytokines, including tumor necrosis factor α (TNF-α) and interleukin (IL)-6. In addition, animals treated with linalool had a marked improvement in survival. These findings have uncovered that linalool acts as a novel Nrf-2 activator for a novel therapeutic strategy in pathogen-mediated lung inflammation.

  10. Inhibition of 5-Lipoxygenase Pathway Attenuates Acute Liver Failure by Inhibiting Macrophage Activation

    Directory of Open Access Journals (Sweden)

    Lu Li

    2014-01-01

    Full Text Available This study aimed to investigate the role of 5-lipoxygenase (5-LO in acute liver failure (ALF and changes in macrophage activation by blocking it. ALF was induced in rats by administration of D-galactosamine (D-GalN/lipopolysaccharide (LPS. Rats were injected intraperitoneally with AA-861 (a specific 5-LO inhibitor, 24 hr before D-GalN/LPS administration. After D-GalN/LPS injection, the liver tissue was collected for assessment of histology, macrophage microstructure, macrophage counts, 5-LO mRNA formation, protein expression, and concentration of leukotrienes. Serum was collected for detecting alanine aminotransferase (ALT, aspartate transaminase (AST, total bilirubin (Tbil, and tumor necrosis factor- (TNF-α. Twenty-four hours after injection, compared with controls, ALF rats were characterized by widespread hepatocyte necrosis and elevated ALT, AST, and Tbil, and 5-LO protein expression reached a peak. Liver leukotriene B4 was also significantly elevated. However, 5-LO mRNA reached a peak 8 hr after D-GalN/LPS injection. Simultaneously, the microstructure of macrophages was changed most significantly and macrophages counts were increased significantly. Moreover, serum TNF-α was also elevated. By contrast, AA-861 pretreatment significantly decreased liver necrosis as well as all of the parameters compared with the rats without pretreatment. Macrophages, via the 5-LO pathway, play a critical role in ALF, and 5-LO inhibitor significantly alleviates ALF, possibly related to macrophage inhibition.

  11. Valproic acid attenuates microgliosis in injured spinal cord and purinergic P2X4 receptor expression in activated microglia.

    Science.gov (United States)

    Lu, Wen-Hsin; Wang, Chih-Yen; Chen, Po-See; Wang, Jing-Wen; Chuang, De-Maw; Yang, Chung-Shi; Tzeng, Shun-Fen

    2013-05-01

    Peripheral injection with a high dose of valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, into animals with mild or moderate spinal cord injury (SCI) for 1 week can reduce spinal cord tissue loss and promote hindlimb locomotor recovery. A purinergic adenosine triphosphate (ATP) receptor subtype, P2X4 receptor (P2X4 R), has been considered as a potential target to diminish SCI-associated inflammatory responses. In this study, using a minipump-based infusion system, we found that intraspinal infusion with VPA for 3 days into injured spinal cord significantly improved hindlimb locomotion of rats with severe SCI induced by a 10-g NYU impactor dropping from the height of 50 mm onto the spinal T9/10 segment. The neuronal fibers in the injured spinal cord tissues were significantly preserved in VPA-treated rats compared with those observed in vehicle-treated animals. Moreover, the accumulation of microglia/macrophages and astrocytes in the injured spinal cord was attenuated in the animal group receiving VPA infusion. VPA also significantly reduced P2X4 R expression post-SCI. Furthermore, in vitro study indicated that VPA, but not the other HDAC inhibitors, sodium butyrate and trichostatin A (TSA), caused downregulation of P2X4 R in microglia activated with lipopolysaccharide (LPS). Moreover, p38 mitogen-activated protein kinase (MAPK)-triggered signaling was involved in the effect of VPA on the inhibition of P2X4 R gene expression. In addition to the findings from others, our results also provide important evidence to show the inhibitory effect of VPA on P2X4 R expression in activated microglia, which may contribute to reduction of SCI-induced gliosis and subsequently preservation of spinal cord tissues. © 2013 Wiley Periodicals, Inc.

  12. Comparative analysis of electroencephalographic tests of alpha activity attenuation in evaluation of involuntary falling asleep in healthy adults

    Directory of Open Access Journals (Sweden)

    Šundrić Zvonko

    2010-01-01

    Full Text Available Introduction. Decrease of daily alertness is a common cause of accidents in the work place, especially traffic accidents. Therefore, an increasing interest exists to determine reliable indicators of a tendency to fall asleep involuntarily. Objective. To determine an optimal electroencephalographic (EEG indicator of an involuntary tendency to fall asleep, we performed a study on neurologically healthy subjects, after one night of sleep deprivation. Total sleep deprivation was aimed at increasing daily sleepiness in healthy subjects, providing us with an opportunity to test different methods of evaluation. Methods. We applied a visual analogue scale for sleepiness (VASS, EEG registration with the specific test of alpha activity attenuation (TAA in 87 healthy subjects. The test was performed in a standard way (sTAA as well as in accordance with new modifications related to changes of EEG filter width in the range from 5 to 32 Hz (mTAA. Results. After sleep deprivation, we observed involuntary falling asleep in 54 subjects. The comparison of VASS results showed no differences, contrary to a more objective TAA. Between two variants of TAA, the modified test provided us with a better prediction for subjects who would fall asleep involuntarily. Conclusion. The application of a more objective EEG test in evaluation of daily alertness represents the optimal method of testing. Modified TAA attracts special attention, offering a simple solution for reliable testing of decreased daily alertness in medical services related to professional aircraft personnel.

  13. Lack of Platelet-Activating Factor Receptor Attenuates Experimental Food Allergy but Not Its Metabolic Alterations regarding Adipokine Levels

    Science.gov (United States)

    Batista, Nathália Vieira; Fonseca, Roberta Cristelli; Perez, Denise; Pereira, Rafaela Vaz Sousa; de Lima Alves, Juliana; Pinho, Vanessa; Faria, Ana Maria Caetano; Cara, Denise Carmona

    2016-01-01

    Platelet-activating factor (PAF) is known to be an important mediator of anaphylaxis. However, there is a lack of information in the literature about the role of PAF in food allergy. The aim of this work was to elucidate the participation of PAF during food allergy development and the consequent adipose tissue inflammation along with its alterations. Our data demonstrated that, both before oral challenge and after 7 days receiving ovalbumin (OVA) diet, OVA-sensitized mice lacking the PAF receptor (PAFR) showed a decreased level of anti-OVA IgE associated with attenuated allergic markers in comparison to wild type (WT) mice. Moreover, there was less body weight and adipose tissue loss in PAFR-deficient mice. However, some features of inflamed adipose tissue presented by sensitized PAFR-deficient and WT mice after oral challenge were similar, such as a higher rate of rolling leukocytes in this tissue and lower circulating levels of adipokines (resistin and adiponectin) in comparison to nonsensitized mice. Therefore, PAF signaling through PAFR is important for the allergic response to OVA but not for the adipokine alterations caused by this inflammatory process. Our work clarifies some effects of PAF during food allergy along with its role on the metabolic consequences of this inflammatory process. PMID:27314042

  14. Berberine hydrochloride attenuates lipopolysaccharide-induced endometritis in mice by suppressing activation of NF-κB signal pathway.

    Science.gov (United States)

    Fu, Kaiqiang; Lv, Xiaopei; Li, Weishi; Wang, Yu; Li, Huatao; Tian, Wenru; Cao, Rongfeng

    2015-01-01

    Endometritis is a common disease in animal production and influences breeding all over the world. Berberine is one of the main alkaloids isolated from Rhizoma coptidis. Previous reports showed that berberine has anti-inflammatory potential. However, there have been a limited number of published reports on the anti-inflammatory effect of berberine hydrochloride on LPS-induced endometritis. The purpose of the present study was to investigate the effects of berberine hydrochloride on LPS-induced mouse endometritis. Berberine hydrochloride was administered intraperitoneally at 1h before and 12h after LPS induction. Then, a biopsy was performed, and uterine myeloperoxidase (MPO) and nitric oxide (NO) concentrations were determined. Tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) levels in the uterus homogenate were measured by ELISA. The extent of IκB-α and P65 phosphorylation was detected by Western blot. The results showed that berberine hydrochloride significantly attenuated neutrophil infiltration, suppressed myeloperoxidase activity and decreased NO, TNF-αand IL-1βproduction. Furthermore, berberine hydrochloride inhibited the phosphorylation of the NF-κB p65 subunit and the degradation of its inhibitor, IκBα. These findings suggest that berberine hydrochloride exerts potent anti-inflammatory effects on LPS-induced mouse endometritis and might be a potential therapeutic agent for endometritis. PMID:25479718

  15. CD28/B7 Deficiency Attenuates Systolic Overload-Induced Congestive Heart Failure, Myocardial and Pulmonary Inflammation, and Activated T Cell Accumulation in the Heart and Lungs.

    Science.gov (United States)

    Wang, Huan; Kwak, Dongmin; Fassett, John; Hou, Lei; Xu, Xin; Burbach, Brandon J; Thenappan, Thenappan; Xu, Yawei; Ge, Jun-Bo; Shimizu, Yoji; Bache, Robert J; Chen, Yingjie

    2016-09-01

    The inflammatory response regulates congestive heart failure (CHF) development. T cell activation plays an important role in tissue inflammation. We postulate that CD28 or B7 deficiency inhibits T cell activation and attenuates CHF development by reducing systemic, cardiac, and pulmonary inflammation. We demonstrated that chronic pressure overload-induced end-stage CHF in mice is characterized by profound accumulation of activated effector T cells (CD3(+)CD44(high) cells) in the lungs and a mild but significant increase of these cells in the heart. In knockout mice lacking either CD28 or B7, there was a dramatic reduction in the accumulation of activated effector T cells in both hearts and lungs of mice under control conditions and after transverse aortic constriction. CD28 or B7 knockout significantly attenuated transverse aortic constriction-induced CHF development, as indicated by less increase of heart and lung weight and less reduction of left ventricle contractility. CD28 or B7 knockout also significantly reduced transverse aortic constriction-induced CD45(+) leukocyte, T cell, and macrophage infiltration in hearts and lungs, lowered proinflammatory cytokine expression (such as tumor necrosis factor-α and interleukin-1β) in lungs. Furthermore, CD28/B7 blockade by CTLA4-Ig treatment (250 μg/mouse every 3 days) attenuated transverse aortic constriction-induced T cell activation, left ventricle hypertrophy, and left ventricle dysfunction. Our data indicate that CD28/B7 deficiency inhibits activated effector T cell accumulation, reduces myocardial and pulmonary inflammation, and attenuates the development of CHF. Our findings suggest that strategies targeting T cell activation may be useful in treating CHF.

  16. Activated endothelial interleukin-1beta, -6, and -8 concentrations and intercellular adhesion molecule-1 expression are attenuated by lidocaine.

    LENUS (Irish Health Repository)

    Lan, Wei

    2012-02-03

    Endothelial cells play a key role in ischemia reperfusion injury. We investigated the effects of lidocaine on activated human umbilical vein endothelial cell (HUVEC) interleukin (IL)-1beta, IL-6, and IL-8 concentrations and intercellular adhesion molecule-1 (ICAM-1) expression. HUVECs were pretreated with different concentrations of lidocaine (0 to 0.5 mg\\/mL) for 60 min, thereafter tumor necrosis factor-alpha was added at a concentration of 2.5 ng\\/mL and the cells incubated for 4 h. Supernatants were harvested, and cytokine concentrations were analyzed by enzyme-linked immunosorbent assay. Endothelial ICAM-1 expression was analyzed by using flow cytometry. Differences were assessed using analysis of variance and post hoc unpaired Student\\'s t-test where appropriate. Lidocaine (0.5 mg\\/mL) decreased IL-1beta (1.89 +\\/- 0.11 versus 4.16 +\\/- 1.27 pg\\/mL; P = 0.009), IL-6 (65.5 +\\/- 5.14 versus 162 +\\/- 11.5 pg\\/mL; P < 0.001), and IL-8 (3869 +\\/- 785 versus 14,961 +\\/- 406 pg\\/mL; P < 0.001) concentrations compared with the control. IL-1beta, IL-6, and IL-8 concentrations in HUVECs treated with clinically relevant plasma concentrations of lidocaine (0.005 mg\\/mL) were similar to control. ICAM-1 expression on lidocaine-treated (0.05 mg\\/mL) HUVECs was less than on controls (198 +\\/- 52.7 versus 298 +\\/- 50.3; Mean Channel Fluorescence; P < 0.001). Activated endothelial IL-1beta, IL-6, and IL-8 concentrations and ICAM-1 expression are attenuated only by lidocaine at concentrations larger than clinically relevant concentrations.

  17. The Groucho co-repressor is primarily recruited to local target sites in active chromatin to attenuate transcription.

    Directory of Open Access Journals (Sweden)

    Aamna Kaul

    2014-08-01

    Full Text Available Gene expression is regulated by the complex interaction between transcriptional activators and repressors, which function in part by recruiting histone-modifying enzymes to control accessibility of DNA to RNA polymerase. The evolutionarily conserved family of Groucho/Transducin-Like Enhancer of split (Gro/TLE proteins act as co-repressors for numerous transcription factors. Gro/TLE proteins act in several key pathways during development (including Notch and Wnt signaling, and are implicated in the pathogenesis of several human cancers. Gro/TLE proteins form oligomers and it has been proposed that their ability to exert long-range repression on target genes involves oligomerization over broad regions of chromatin. However, analysis of an endogenous gro mutation in Drosophila revealed that oligomerization of Gro is not always obligatory for repression in vivo. We have used chromatin immunoprecipitation followed by DNA sequencing (ChIP-seq to profile Gro recruitment in two Drosophila cell lines. We find that Gro predominantly binds at discrete peaks (<1 kilobase. We also demonstrate that blocking Gro oligomerization does not reduce peak width as would be expected if Gro oligomerization induced spreading along the chromatin from the site of recruitment. Gro recruitment is enriched in "active" chromatin containing developmentally regulated genes. However, Gro binding is associated with local regions containing hypoacetylated histones H3 and H4, which is indicative of chromatin that is not fully open for efficient transcription. We also find that peaks of Gro binding frequently overlap the transcription start sites of expressed genes that exhibit strong RNA polymerase pausing and that depletion of Gro leads to release of polymerase pausing and increased transcription at a bona fide target gene. Our results demonstrate that Gro is recruited to local sites by transcription factors to attenuate rather than silence gene expression by promoting histone

  18. Nicotine attenuates activation of tissue resident macrophages in the mouse stomach through the β2 nicotinic acetylcholine receptor.

    Directory of Open Access Journals (Sweden)

    Andrea Nemethova

    Full Text Available BACKGROUND: The cholinergic anti-inflammatory pathway is an endogenous mechanism by which the autonomic nervous system attenuates macrophage activation via nicotinic acetylcholine receptors (nAChR. This concept has however not been demonstrated at a cellular level in intact tissue. To this end, we have studied the effect of nicotine on the activation of resident macrophages in a mouse stomach preparation by means of calcium imaging. METHODS: Calcium transients ([Ca(2+]i in resident macrophages were recorded in a mouse stomach preparation containing myenteric plexus and muscle layers by Fluo-4. Activation of macrophages was achieved by focal puff administration of ATP. The effects of nicotine on activation of macrophages were evaluated and the nAChR involved was pharmacologically characterized. The proximity of cholinergic nerves to macrophages was quantified by confocal microscopy. Expression of β2 and α7 nAChR was evaluated by β2 immunohistochemistry and fluorophore-tagged α-bungarotoxin. RESULTS: In 83% of macrophages cholinergic varicose nerve fibers were detected at distances <900 nm. The ATP induced [Ca(2+]i increase was significantly inhibited in 65% or 55% of macrophages by 100 µM or 10 µM nicotine, respectively. This inhibitory effect was reversed by the β2 nAChR preferring antagonist dihydro-β-eryhtroidine but not by hexamethonium (non-selective nAChR-antagonist, mecamylamine (α3β4 nAChR-preferring antagonist, α-bungarotoxin or methyllycaconitine (both α7 nAChR-preferring antagonist. Macrophages in the stomach express β2 but not α7 nAChR at protein level, while those in the intestine express both receptor subunits. CONCLUSION: This study is the first in situ demonstration of an inhibition of macrophage activation by nicotine suggesting functional signaling between cholinergic neurons and macrophages in the stomach. The data suggest that the β2 subunit of the nAChR is critically involved in the nicotine-induced inhibition

  19. Microglial Cells as a Link between Cannabinoids and the Immune Hypothesis of Psychiatric Disorders

    OpenAIRE

    Lisboa, Sabrina F.; Gomes, Felipe V; Guimaraes, Francisco S.; Campos, Alline C

    2016-01-01

    Psychiatric disorders are one of the leading causes of disability worldwide. Although several therapeutic options are available, the exact mechanisms responsible for the genesis of these disorders remain to be fully elucidated. In the last decade, a body of evidence has supported the involvement of the immune system in the pathophysiology of these conditions. Microglial cells play a significant role in maintaining brain homeostasis and surveillance. Dysregulation of microglial functions has b...

  20. Role of Endoplasmic Reticulum (ER) Stress in Cocaine-Induced Microglial Cell Death

    OpenAIRE

    Costa, Blaise Mathias; Yao, Honghong; Yang, Lu; Buch, Shilpa

    2013-01-01

    While it has been well-documented that drugs of abuse such as cocaine can enhance progression of human immunodeficiency virus (HIV)-associated neuropathological disorders, the underlying mechanisms mediating these effects remain poorly understood. The present study was undertaken to examine the effects of cocaine on microglial viability. Herein we demonstrate that exposure of microglial cell line-BV2 or rat primary microglia to exogenous cocaine resulted in decreased cell viability as determi...

  1. Role of endoplasmic reticulum (ER) stress in cocaine-induced microglial cell death.

    Science.gov (United States)

    Costa, Blaise Mathias; Yao, Honghong; Yang, Lu; Buch, Shilpa

    2013-06-01

    While it has been well-documented that drugs of abuse such as cocaine can enhance progression of human immunodeficiency virus (HIV)-associated neuropathological disorders, the underlying mechanisms mediating these effects remain poorly understood. The present study was undertaken to examine the effects of cocaine on microglial viability. Herein we demonstrate that exposure of microglial cell line-BV2 or rat primary microglia to exogenous cocaine resulted in decreased cell viability as determined by MTS and TUNEL assays. Microglial toxicity of cocaine was accompanied by an increase in the expression of cleaved caspase-3 as demonstrated by western blot assays. Furthermore, increased microglial toxicity was also associated with a concomitant increase in the production of intracellular reactive oxygen species, an effect that was ameliorated in cells pretreated with NADPH oxidase inhibitor apocynin, thus emphasizing the role of oxidative stress in this process. A novel finding of this study was the involvement of endoplasmic reticulum (ER) signaling mediators such as PERK, Elf2α, and CHOP, which were up regulated in cells exposed to cocaine. Reciprocally, blocking CHOP expression using siRNA ameliorated cocaine-mediated cell death. In conclusion these findings underscore the importance of ER stress in modulating cocaine induced microglial toxicity. Understanding the link between ER stress, oxidative stress and apoptosis could lead to the development of therapeutic strategies targeting cocaine-mediated microglial death/dysfunction. PMID:23404095

  2. The microglial NADPH oxidase complex as a source of oxidative stress in Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Landreth Gary E

    2006-11-01

    Full Text Available Abstract Alzheimer's disease is the most common cause of dementia in the elderly, and manifests as progressive cognitive decline and profound neuronal loss. The principal neuropathological hallmarks of Alzheimer's disease are the senile plaques and the neurofibrillary tangles. The senile plaques are surrounded by activated microglia, which are largely responsible for the proinflammatory environment within the diseased brain. Microglia are the resident innate immune cells in the brain. In response to contact with fibrillar beta-amyloid, microglia secrete a diverse array of proinflammatory molecules. Evidence suggests that oxidative stress emanating from activated microglia contribute to the neuronal loss characteristic of this disease. The source of fibrillar beta-amyloid induced reactive oxygen species is primarily the microglial nicotinamide adenine dinucleotide phosphate (NADPH oxidase. The NADPH oxidase is a multicomponent enzyme complex that, upon activation, produces the highly reactive free radical superoxide. The cascade of intracellular signaling events leading to NADPH oxidase assembly and the subsequent release of superoxide in fibrillar beta-amyloid stimulated microglia has recently been elucidated. The induction of reactive oxygen species, as well as nitric oxide, from activated microglia can enhance the production of more potent free radicals such as peroxynitrite. The formation of peroxynitrite causes protein oxidation, lipid peroxidation and DNA damage, which ultimately lead to neuronal cell death. The elimination of beta-amyloid-induced oxidative damage through the inhibition of the NADPH oxidase represents an attractive therapeutic target for the treatment of Alzheimer's disease.

  3. PPARgamma activation attenuates T-lymphocyte-dependent inflammation of adipose tissue and development of insulin resistance in obese mice

    Directory of Open Access Journals (Sweden)

    Unger Thomas

    2010-10-01

    Full Text Available Abstract Background Inflammation of adipose tissue (AT has been recently accepted as a first step towards obesity-mediated insulin resistance. We could previously show that mice fed with high fat diet (HFD develop systemic insulin resistance (IR and glucose intolerance (GI associated with CD4-positive T-lymphocyte infiltration into visceral AT. These T-lymphocytes, when enriched in AT, participate in the development of fat tissue inflammation and subsequent recruitment of proinflammatory macrophages. The aim of this work was to elucidate the action of the insulin sensitizing PPARgamma on T-lymphocyte infiltration during development of IR, and comparison of the PPARgamma-mediated anti-inflammatory effects of rosiglitazone and telmisartan in diet-induced obesity model (DIO-model in mice. Methods In order to investigate the molecular mechanisms underlying early development of systemic insulin resistance and glucose intolerance male C57BL/6J mice were fed with high fat diet (HFD for 10-weeks in parallel to the pharmacological intervention with rosiglitazone, telmisartan, or vehicle. Results Both rosiglitazone and telmisartan were able to reduce T-lymphocyte infiltration into AT analyzed by quantitative analysis of the T-cell marker CD3gamma and the chemokine SDF1alpha. Subsequently, both PPARgamma agonists were able to attenuate macrophage infiltration into AT, measured by the reduction of MCP1 and F4/80 expression. In parallel to the reduction of AT-inflammation, ligand-activated PPARgamma improved diet-induced IR and GI. Conclusion Together the present study demonstrates a close connection between PPARgamma-mediated anti-inflammation in AT and systemic improvement of glucose metabolism identifying T-lymphocytes as one cellular mediator of PPARgamma´s action.

  4. Plasminogen Activator Inhibitor-1 Antagonist TM5484 Attenuates Demyelination and Axonal Degeneration in a Mice Model of Multiple Sclerosis.

    Directory of Open Access Journals (Sweden)

    Nicolas Pelisch

    Full Text Available Multiple sclerosis (MS is characterized by inflammatory demyelination and deposition of fibrinogen in the central nervous system (CNS. Elevated levels of a critical inhibitor of the mammalian fibrinolitic system, plasminogen activator inhibitor 1 (PAI-1 have been demonstrated in human and animal models of MS. In experimental studies that resemble neuroinflammatory disease, PAI-1 deficient mice display preserved neurological structure and function compared to wild type mice, suggesting a link between the fibrinolytic pathway and MS. We previously identified a series of PAI-1 inhibitors on the basis of the 3-dimensional structure of PAI-1 and on virtual screening. These compounds have been reported to provide a number of in vitro and in vivo benefits but none was tested in CNS disease models because of their limited capacity to penetrate the blood-brain barrier (BBB. The existing candidates were therefore optimized to obtain CNS-penetrant compounds. We performed an in vitro screening using a model of BBB and were able to identify a novel, low molecular PAI-1 inhibitor, TM5484, with the highest penetration ratio among all other candidates. Next, we tested the effects on inflammation and demyelination in an experimental allergic encephalomyelitis mice model. Results were compared to either fingolimod or 6α-methylprednisolone. Oral administration of TM5484 from the onset of signs, ameliorates paralysis, attenuated demyelination, and axonal degeneration in the spinal cord of mice. Furthermore, it modulated the expression of brain-derived neurotrophic factor, which plays a protective role in neurons against various pathological insults, and choline acetyltransferase, a marker of neuronal density. Taken together, these results demonstrate the potential benefits of a novel PAI-1 inhibitor, TM5484, in the treatment of MS.

  5. BET Inhibition Attenuates Helicobacter pylori-Induced Inflammatory Response by Suppressing Inflammatory Gene Transcription and Enhancer Activation.

    Science.gov (United States)

    Chen, Jinjing; Wang, Zhen; Hu, Xiangming; Chen, Ruichuan; Romero-Gallo, Judith; Peek, Richard M; Chen, Lin-Feng

    2016-05-15

    Helicobacter pylori infection causes chronic gastritis and peptic ulceration. H. pylori-initiated chronic gastritis is characterized by enhanced expression of many NF-κB-regulated inflammatory cytokines. Brd4 has emerged as an important NF-κB regulator and regulates the expression of many NF-κB-dependent inflammatory genes. In this study, we demonstrated that Brd4 was not only actively involved in H. pylori-induced inflammatory gene mRNA transcription but also H. pylori-induced inflammatory gene enhancer RNA (eRNA) synthesis. Suppression of H. pylori-induced eRNA synthesis impaired H. pylori-induced mRNA synthesis. Furthermore, H. pylori stimulated NF-κB-dependent recruitment of Brd4 to the promoters and enhancers of inflammatory genes to facilitate the RNA polymerase II-mediated eRNA and mRNA synthesis. Inhibition of Brd4 by JQ1 attenuated H. pylori-induced eRNA and mRNA synthesis for a subset of NF-κB-dependent inflammatory genes. JQ1 also inhibited H. pylori-induced interaction between Brd4 and RelA and the recruitment of Brd4 and RNA polymerase II to the promoters and enhancers of inflammatory genes. Finally, we demonstrated that JQ1 suppressed inflammatory gene expression, inflammation, and cell proliferation in H. pylori-infected mice. These studies highlight the importance of Brd4 in H. pylori-induced inflammatory gene expression and suggest that Brd4 could be a potential therapeutic target for the treatment of H. pylori-triggered inflammatory diseases and cancer. PMID:27084101

  6. Curcumin Attenuates Beta-Amyloid-Induced Neuroinflammation via Activation of Peroxisome Proliferator-Activated Receptor-Gamma Function in a Rat Model of Alzheimer's Disease.

    Science.gov (United States)

    Liu, Zun-Jing; Li, Zhong-Hao; Liu, Lei; Tang, Wen-Xiong; Wang, Yu; Dong, Ming-Rui; Xiao, Cheng

    2016-01-01

    Neuroinflammation is known to have a pivotal role in the pathogenesis of Alzheimer's disease (AD), and curcumin has been reported to have therapeutical effects on AD because of its anti-inflammatory effects. Curcumin is not only a potent PPARγ agonist, but also has neuroprotective effects on cerebral ischemic injury. However, whether PPARγ activated by curcumin is responsible for the anti-neuroinflammation and neuroprotection on AD remains unclear, and needs to be further investigated. Here, using both APP/PS1 transgenic mice and beta-amyloid-induced neuroinflammation in mixed neuronal/glial cultures, we showed that curcumin significantly alleviated spatial memory deficits in APP/PS1 mice and promoted cholinergic neuronal function in vivo and in vitro. Curcumin also reduced the activation of microglia and astrocytes, as well as cytokine production and inhibited nuclear factor kappa B (NF-κB) signaling pathway, suggesting the beneficial effects of curcumin on AD are attributable to the suppression of neuroinflammation. Attenuation of these beneficial effects occurred when co-administrated with PPARγ antagonist GW9662 or silence of PPARγ gene expression, indicating that PPARγ might be involved in anti-inflammatory effects. Circular dichroism and co-immunoprecipitation analysis showed that curcumin directly bound to PPARγ and increased the transcriptional activity and protein levels of PPARγ. Taking together, these data suggested that PPARγ might be a potential target of curcumin, acting to alleviate neuroinflammation and improve neuronal function in AD. PMID:27594837

  7. Cardiac Shock Wave Therapy Attenuates H9c2 Myoblast Apoptosis by Activating the AKT Signal Pathway

    Directory of Open Access Journals (Sweden)

    Weiwei Yu

    2014-04-01

    Full Text Available Background: Previous studies have demonstrated that Cardiac Shock Wave Therapy (CSWT improves myocardial perfusion and cardiac function in a porcine model of chronic myocardial ischemia and also ameliorates myocardial ischemia in patients with severe coronary artery disease (CAD. Apoptosis plays a key role in ischemic myocardial pathogenesis. However, it remains unclear whether CSWT is beneficial for ischemia/hypoxia (I/H-induced myocardial cell apoptosis and by which mechanism CSWT could improve heart function. We put forward the hypothesis that CSWT might protect heart function during ischemia/hypoxia by decreasing apoptosis. Methods: We generated ischemia/hypoxia (I/H-induced apoptosis in the H9c2 myoblast cell line to examine the CSWT function and possible mechanisms. H9c2 cells were treated under hypoxic serum-starved conditions for 24 h and then treated with or without CSWT (500 shots, 0.06, 0.09, 0.12mJ/mm2. The apoptotic cell rate was determined by flow cytometry assay, cell viability was examined by the MTT assay, nuclear fragmentation was detected by Hoechst 33342 staining, and the mitochondrial-mediated intrinsic pathway of apoptosis was assessed by the expression of Bax and Bcl-2 protein and Caspase3 activation. Results: First, apoptosis could be induced by ischemia/hypoxia in H9c2 cells. Second, CSWT attenuates the cell death and decreases the H9c2 cell apoptosis rate induced by ischemia and hypoxia. Third, CSWT suppresses the expression of apoptosis molecules that regulate the intrinsic pathway of apoptosis in H9c2 cells. Fourth, CSWT increases the phosphorylation of AKT, which indicates the activation of the PI3K-AKT pathway. Conclusions: These results indicate that CSWT exerts a protective effect against I/H-induced cell death, potentially by preventing the activation of components of the mitochondrial-dependent intrinsic apoptotic pathway. We also demonstrate that the PI3K-Akt pathway may be involved in the CSWT effects on

  8. A TIR domain protein from E. faecalis attenuates MyD88-mediated signaling and NF-κB activation.

    Directory of Open Access Journals (Sweden)

    Jun Zou

    Full Text Available Toll-like receptor signaling, mediated by functional Toll/interleukin-1 receptor (TIR domains, plays a critical role in activating the innate immune response responsible for controlling and clearing infection. Bacterial protein mimics of components of this signaling pathway have been identified and function through inhibition of interactions between Toll-like receptors (TLRs and their adaptor proteins, mediated by TIR domains. A previously uncharacterized gene, which we have named tcpF (for TIR domain-containing protein in E. faecalis was identified in the genome of Enterococcus faecalis V583, and predicted to encode a protein resembling mammalian and bacterial TIR proteins. We overexpressed and purified TcpF from E. coli and found that the recombinant protein could bind to phosphatidylinositol phosphates in vitro, suggesting a mechanism by which TcpF may be anchored to the plasma membrane in close proximity to TIR domains of TLRs and adaptor proteins. Purified TcpF was also found to interact specifically with the TIR adaptor protein MyD88, and this interaction was dependent on the BB loop domain in the Box 2 region of TcpF. Despite no evidence of TcpF being a secreted protein, recombinant TcpF was effectively able to enter RAW264.7 cells in vitro although the mechanism by which this occurs remains to be determined. Overexpression of TcpF in mammalian cells suppressed the NF-κB activation induced by bacterial lipoteichoic acid. A mutant lacking the tcpF gene was attenuated for survival in macrophages, with increased ability to activate NF-κB compared to the wild type strain. Complementation in trans restored growth, and inhibition of NF-κB, to that of wild type levels. No appreciable difference in bacterial persistence, dissemination or pathogenesis was observed between the wild type and mutant in a mouse peritonitis model however, which suggested either a subtle role for TcpF or functional overlap with other redundant factor(s in this

  9. Microglial KCa3.1 Channels as a Potential Therapeutic Target for Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Izumi Maezawa

    2012-01-01

    Full Text Available There exists an urgent need for new target discovery to treat Alzheimer’s disease (AD; however, recent clinical trials based on anti-Aβ and anti-inflammatory strategies have yielded disappointing results. To expedite new drug discovery, we propose reposition targets which have been previously pursued by both industry and academia for indications other than AD. One such target is the calcium-activated potassium channel KCa3.1 (KCNN4, which in the brain is primarily expressed in microglia and is significantly upregulated when microglia are activated. We here review the existing evidence supporting that KCa3.1 inhibition could block microglial neurotoxicity without affecting their neuroprotective phagocytosis activity and without being broadly immunosuppressive. The anti-inflammatory and neuroprotective effects of KCa3.1 blockade would be suitable for treating AD as well as cerebrovascular and traumatic brain injuries, two well-known risk factors contributing to the dementia in AD patients presenting with mixed pathologies. Importantly, the pharmacokinetics and pharmacodynamics of several KCa3.1 blockers are well known, and a KCa3.1 blocker has been proven safe in clinical trials. It is therefore promising to reposition old or new KCa3.1 blockers for AD preclinical and clinical trials.

  10. Physical activity attenuates the influence of FTO variants on obesity risk: a meta-analysis of 218,166 adults and 19,268 children.

    Directory of Open Access Journals (Sweden)

    Tuomas O Kilpeläinen

    2011-11-01

    Full Text Available The FTO gene harbors the strongest known susceptibility locus for obesity. While many individual studies have suggested that physical activity (PA may attenuate the effect of FTO on obesity risk, other studies have not been able to confirm this interaction. To confirm or refute unambiguously whether PA attenuates the association of FTO with obesity risk, we meta-analyzed data from 45 studies of adults (n = 218,166 and nine studies of children and adolescents (n = 19,268.All studies identified to have data on the FTO rs9939609 variant (or any proxy [r(2>0.8] and PA were invited to participate, regardless of ethnicity or age of the participants. PA was standardized by categorizing it into a dichotomous variable (physically inactive versus active in each study. Overall, 25% of adults and 13% of children were categorized as inactive. Interaction analyses were performed within each study by including the FTO×PA interaction term in an additive model, adjusting for age and sex. Subsequently, random effects meta-analysis was used to pool the interaction terms. In adults, the minor (A- allele of rs9939609 increased the odds of obesity by 1.23-fold/allele (95% CI 1.20-1.26, but PA attenuated this effect (p(interaction  = 0.001. More specifically, the minor allele of rs9939609 increased the odds of obesity less in the physically active group (odds ratio  = 1.22/allele, 95% CI 1.19-1.25 than in the inactive group (odds ratio  = 1.30/allele, 95% CI 1.24-1.36. No such interaction was found in children and adolescents.The association of the FTO risk allele with the odds of obesity is attenuated by 27% in physically active adults, highlighting the importance of PA in particular in those genetically predisposed to obesity.

  11. Attenuated Leishmania induce pro-inflammatory mediators and influence leishmanicidal activity by p38 MAPK dependent phagosome maturation in Leishmania donovani co-infected macrophages

    OpenAIRE

    Somenath Banerjee; Dipayan Bose; Nabanita Chatterjee; Subhadip Das; Sreeparna Chakraborty; Tanya Das; Krishna Das Saha

    2016-01-01

    Promastigote form of Leishmania, an intracellular pathogen, delays phagosome maturation and resides inside macrophages. But till date limited study has been done to manipulate the phagosomal machinery of macrophages to restrict Leishmania growth. Attenuated Leishmania strain exposed RAW 264.7 cells showed a respiratory burst and enhanced production of pro-inflammatory mediators. The augmentation of pro-inflammatory activity is mostly attributed to p38 MAPK and p44/42 MAPK. In our study, these...

  12. Decreased hepatic phosphorylated p38 mitogen-activated protein kinase contributes to attenuation of thioacetamide-induced hepatic necrosis in diet-induced obese mice.

    Science.gov (United States)

    Shirai, Makoto; Arakawa, Shingo; Teranishi, Munehiro; Kai, Kiyonori

    2016-04-01

    We previously reported that thioacetamide (TA)-induced hepatocellular necrosis was attenuated in mice fed a high-fat diet (HFD mice) compared with mice fed a normal rodent diet (ND mice). In this study, we investigated whether p38 mitogen-activated protein kinase (p38 MAPK) was involved in this attenuation. Western blot analysis revealed that hepatic phosphorylated p38 MAPK protein decreased at 8 and 24 hours (hr) after TA dosing in the HFD mice, while it decreased only at 24 hr in the ND mice in comparison to the time- and diet-matched, vehicle-treated mice. p38 MAPK regulates various biological functions including inflammation, therefore, hepatic metabolomics analysis focusing on pro-inflammatory lipid mediators was performed. At 24 hr after TA dosing, only one pro-inflammatory mediator, 12-hydroxyeicosatetraenoic acid (HETE), was higher in the HFD mice. On the other hand, in addition to 12-HETE, 15-HETE and 12-hydroxyeicosapentaenoic acid (HEPE) were higher and omega-3/omega-6 polyunsaturated fatty acids ratios were lower in the ND mice at 24 hr. These results of metabolomics indicated that less pro-inflammatory state was seen in HFD mice than in ND mice at 24 hr. Finally, to confirm whether the observed decrease in phosphorylated p38 MAPK could attenuate TA-induced hepatocellular necrosis, we showed that SB203580 hydrochloride, an inhibitor of p38 MAPK, partially attenuated TA-induced hepatic necrosis in ND mice. Collectively, these results suggest that a prompt decrease in phosphorylation of p38 MAPK after TA administration is one of the factors that attenuate TA-induced hepatic necrosis in HFD mice. PMID:26961609

  13. Contact-independent cell death of human microglial cells due to pathogenic Naegleria fowleri trophozoites.

    Science.gov (United States)

    Kim, Jong-Hyun; Kim, Daesik; Shin, Ho-Joon

    2008-12-01

    Free-living Naegleria fowleri leads to a fatal infection known as primary amebic meningoencephalitis in humans. Previously, the target cell death could be induced by phagocytic activity of N. fowleri as a contact-dependent mechanism. However, in this study we investigated the target cell death under a non-contact system using a tissue-culture insert. The human microglial cells, U87MG cells, co-cultured with N. fowleri trophozoites for 30 min in a non-contact system showed morphological changes such as the cell membrane destruction and a reduction in the number. By fluorescence-activated cell sorter (FACS) analysis, U87MG cells co-cultured with N. fowleri trophozoites in a non-contact system showed a significant increase of apoptotic cells (16%) in comparison with that of the control or N. fowleri lysate. When U87MG cells were co-cultured with N. fowleri trophozoites in a non-contact system for 30 min, 2 hr, and 4 hr, the cytotoxicity of amebae against target cells was 40.5, 44.2, and 45.6%, respectively. By contrast, the cytotoxicity of non-pathogenic N. gruberi trophozoites was 10.2, 12.4, and 13.2%, respectively. These results suggest that the molecules released from N. fowleri in a contact-independent manner as well as phagocytosis in a contact-dependent manner may induce the host cell death.

  14. From blood to brain: amoeboid microglial cell, a nascent macrophage and its functions in developing brain

    Institute of Scientific and Technical Information of China (English)

    Charanjit KAUR; S Thameem DHEEN; Eng-ang LING

    2007-01-01

    Amoeboid microglial cells (AMC) in the developing brain are active macrophages.The macrophagic nature of these cells has been demonstrated by many methods,such as the localization of various hydrolytic enzymes and the presence of comple-ment type 3 surface receptors in them. More importantly is the direct visualization of these cells engaged in the phagocytosis of degenerating cells at the ultrastruc-tural level. Further evidence of them being active macrophages is the avid inter-nalization of tracers administered by the intravenous or intraperitoneal routes in developing rats. The potential involvement of AMC in immune functions is sup-ported by the induced expression of major histocompatibility complex class Ⅰ and Ⅱ antigens on them when challenged by lipopolysaccharide or interferon-γ. Im-munosuppressive drugs, such as glucocorticoids and immune function-enhanc-ing drugs like melatonin, affect the expression of surface receptors and antigens and the release of cytokines by AMC. Recent studies in our laboratory have shown the expression of insulin-like growth factors, endothelins, 21,31-cyclic nucle-otide 31-phosphodiesterase, and N-methyl-D-asparate receptors. This along with the release of chemokines, such as stromal derived factor-la and monocyte chemoattractant protein-1, suggests multiple functional roles of AMC in early brain development.

  15. Microglial Scavenger Receptors and Their Roles in the Pathogenesis of Alzheimer's Disease

    Directory of Open Access Journals (Sweden)

    Kim Wilkinson

    2012-01-01

    Full Text Available Alzheimer’s disease (AD is increasing in prevalence with the aging population. Deposition of amyloid-β (Aβ in the brain of AD patients is a hallmark of the disease and is associated with increased microglial numbers and activation state. The interaction of microglia with Aβ appears to play a dichotomous role in AD pathogenesis. On one hand, microglia can phagocytose and clear Aβ, but binding of microglia to Aβ also increases their ability to produce inflammatory cytokines, chemokines, and neurotoxic reactive oxygen species (ROS. Scavenger receptors, a group of evolutionally conserved proteins expressed on the surface of microglia act as receptors for Aβ. Of particular interest are SCARA-1 (scavenger receptor A-1, CD36, and RAGE (receptor for advanced glycation end products. SCARA-1 appears to be involved in the clearance of Aβ, while CD36 and RAGE are involved in activation of microglia by Aβ. In this review, we discuss the roles of various scavenger receptors in the interaction of microglia with Aβ and propose that these receptors play complementary, nonredundant functions in the development of AD pathology. We also discuss potential therapeutic applications for these receptors in AD.

  16. Attenuated recombinant vaccinia virus expressing oncofetal antigen (tumor-associated antigen) 5T4 induces active therapy of established tumors.

    Science.gov (United States)

    Mulryan, Kate; Ryan, Matthew G; Myers, Kevin A; Shaw, David; Wang, Who; Kingsman, Susan M; Stern, Peter L; Carroll, Miles W

    2002-10-01

    The human oncofetal antigen 5T4 (h5T4) is a transmembrane glycoprotein overexpressed by a wide spectrum of cancers, including colorectal, ovarian, and gastric, but with a limited normal tissue expression. Such properties make 5T4 an excellent putative target for cancer immunotherapy. The murine homologue of 5T4 (m5T4) has been cloned and characterized, which allows for the evaluation of immune intervention strategies in "self-antigen" in vivo tumor models. We have constructed recombinant vaccinia viruses based on the highly attenuated and modified vaccinia virus ankara (MVA strain), expressing h5T4 (MVA-h5T4), m5T4 (MVA-m5T4), and Escherichia coli LacZ (MVA-LacZ). Immunization of BALB/c and C57BL/6 mice with MVA-h5T4 and MVA-m5T4 constructs induced antibody responses to human and mouse 5T4, respectively. C57BL/6 and BALB/c mice vaccinated with MVA-h5T4 were challenged with syngeneic tumor line transfectants, B16 melanoma, and CT26 colorectal cells that express h5T4. MVA-h5T4-vaccinated mice showed significant tumor retardation compared with mice vaccinated with MVA-LacZ or PBS. In active treatment studies, inoculation with MVA-h5T4 was able to treat established CT26-h5T4 lung tumor and to a lesser extent B16.h5T4 s.c. tumors. Additionally, when C57BL/6 mice vaccinated with MVA-m5T4 were challenged with B16 cells expressing m5T4, resulting growth of the tumors was significantly retarded compared with control animals. Furthermore, mice vaccinated with MVA-m5T4 showed no signs of autoimmune toxicity. These data support the use of MVA-5T4 for tumor immunotherapy. PMID:12481437

  17. IgM-Enriched Immunoglobulin Attenuates Systemic Endotoxin Activity in Early Severe Sepsis: A Before-After Cohort Study

    Science.gov (United States)

    Kirbach, Christin; Warszawska, Joanna; Meybohm, Patrick; Zacharowski, Kai; Koch, Alexander

    2016-01-01

    Introduction Sepsis remains associated with a high mortality rate. Endotoxin has been shown to influence viscoelastic coagulation parameters, thus suggesting a link between endotoxin levels and the altered coagulation phenotype in septic patients. This study evaluated the effects of systemic polyspecific IgM-enriched immunoglobulin (IgM-IVIg) (Pentaglobin® [Biotest, Dreieich, Germany]) on endotoxin activity (EA), inflammatory markers, viscoelastic and conventional coagulation parameters. Methods Patients with severe sepsis were identified by daily screening in a tertiary, academic, surgical ICU. After the inclusion of 15 patients, the application of IgM-IVIg (5 mg/kg/d over three days) was integrated into the unit’s standard operation procedure (SOP) to treat patients with severe sepsis, thereby generating “control” and “IgM-IVIg” groups. EA assays, thrombelastometry (ROTEM®) and impedance aggregometry (Multiplate®) were performed on whole blood. Furthermore, routine laboratory parameters were determined according to unit’s standards. Results Data from 26 patients were included. On day 1, EA was significantly decreased in the IgM-IVIg group following 6 and 12 hours of treatment (0.51 ±0.06 vs. 0.26 ±0.07, p<0.05 and 0.51 ±0.06 vs. 0.25 ±0.04, p<0.05) and differed significantly compared with the control group following 6 hours of treatment (0.26 ±0.07 vs. 0.43 ±0.07, p<0.05). The platelet count was significantly higher in the IgM-IVIg group following four days of IgM-IVIg treatment (200/nl ±43 vs. 87/nl ±20, p<0.05). The fibrinogen concentration was significantly lower in the control group on day 2 (311 mg/dl ±37 vs. 475 mg/dl ±47 (p = 0.015)) and day 4 (307 mg/dl ±35 vs. 420 mg/dl ±16 (p = 0.017)). No differences in thrombelastometric or aggregometric measurements, or inflammatory markers (interleukin-6 (IL-6), leukocyte, lipopolysaccharide binding protein (LBP)) were observed. Conclusion Treatment with IgM-enriched immunoglobulin

  18. Attenuated Leishmania induce pro-inflammatory mediators and influence leishmanicidal activity by p38 MAPK dependent phagosome maturation in Leishmania donovani co-infected macrophages.

    Science.gov (United States)

    Banerjee, Somenath; Bose, Dipayan; Chatterjee, Nabanita; Das, Subhadip; Chakraborty, Sreeparna; Das, Tanya; Saha, Krishna Das

    2016-01-01

    Promastigote form of Leishmania, an intracellular pathogen, delays phagosome maturation and resides inside macrophages. But till date limited study has been done to manipulate the phagosomal machinery of macrophages to restrict Leishmania growth. Attenuated Leishmania strain exposed RAW 264.7 cells showed a respiratory burst and enhanced production of pro-inflammatory mediators. The augmentation of pro-inflammatory activity is mostly attributed to p38 MAPK and p44/42 MAPK. In our study, these activated macrophages are found to induce phagosome maturation when infected with pathogenic Leishmania donovani. Increased co-localization of carboxyfluorescein succinimidyl ester labeled pathogenic L. donovani with Lysosome was found. Moreover, increased co-localization was observed between pathogenic L. donovani and late phagosomal markers viz. Rab7, Lysosomal Associated Membrane Protein 1, Cathepsin D, Rab9, and V-ATPase which indicate phagosome maturation. It was also observed that inhibition of V-type ATPase caused significant hindrance in attenuated Leishmania induced phagosome maturation. Finally, it was confirmed that p38 MAPK is the key player in acidification and maturation of phagosome in attenuated Leishmania strain pre-exposed macrophages. To our knowledge, this study for the first time reported an approach to induce phagosome maturation in L. donovani infected macrophages which could potentiate short-term prophylactic response in future. PMID:26928472

  19. Curcumin attenuates glutamate neurotoxicity in the hippocampus by suppression of ER stress-associated TXNIP/NLRP3 inflammasome activation in a manner dependent on AMPK

    Energy Technology Data Exchange (ETDEWEB)

    Li, Ying; Li, Jia; Li, Shanshan; Li, Yi; Wang, Xiangxiang; Liu, Baolin [Department of Pharmacology of Chinese Materia Medica, China Pharmaceutical University, Nanjing, 639, Longmian Road, Nanjing 211198 (China); Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Research, China Pharmaceutical University, 639, Longmian Road, Nanjing 211198 (China); Fu, Qiang, E-mail: fuqiang@cpu.edu.cn [Department of Pharmacology of Chinese Materia Medica, China Pharmaceutical University, Nanjing, 639, Longmian Road, Nanjing 211198 (China); Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Research, China Pharmaceutical University, 639, Longmian Road, Nanjing 211198 (China); Ma, Shiping, E-mail: spma@cpu.edu.cn [Department of Pharmacology of Chinese Materia Medica, China Pharmaceutical University, Nanjing, 639, Longmian Road, Nanjing 211198 (China); Jiangsu Provincial Key Laboratory for TCM Evaluation and Translational Research, China Pharmaceutical University, 639, Longmian Road, Nanjing 211198 (China)

    2015-07-01

    Curcumin is a natural polyphenolic compound in Curcuma longa with beneficial effects on neuronal protection. This study aims to investigate the action of curcumin in the hippocampus subjected to glutamate neurotoxicity. Glutamate stimulation induced reactive oxygen species (ROS), endoplasmic reticulum stress (ER stress) and TXNIP/NLRP3 inflammasome activation, leading to damage in the hippocampus. Curcumin treatment in the hippocampus or SH-SY5Y cells inhibited IRE1α and PERK phosphorylation with suppression of intracellular ROS production. Curcumin increased AMPK activity and knockdown of AMPKα with specific siRNA abrogated its inhibitory effects on IRE1α and PERK phosphorylation, indicating that AMPK activity was essential for the suppression of ER stress. As a result, curcumin reduced TXNIP expression and inhibited NLRP3 inflammasome activation by downregulation of NLRP3 and cleaved caspase-1 induction, and thus reduced IL-1β secretion. Specific fluorescent probe and flow cytometry analysis showed that curcumin prevented mitochondrial malfunction and protected cell survival from glutamate neurotoxicity. Moreover, oral administration of curcumin reduced brain infarct volume and attenuated neuronal damage in rats subjected to middle cerebral artery occlusion. Immunohistochemistry showed that curcumin inhibited p-IRE1α, p-PERK and NLRP3 expression in hippocampus CA1 region. Together, these results showed that curcumin attenuated glutamate neurotoxicity by inhibiting ER stress-associated TXNIP/NLRP3 inflammasome activation via the regulation of AMPK, and thereby protected the hippocampus from ischemic insult. - Highlights: • Curcumin attenuates glutamate neurotoxicity in the hippocampus. • Curcumin suppresses ER stress in glutamate-induced hippocampus slices. • Curcumin inhibits TXNIP/NLRP3 inflammasome activation. • Regulation of AMPK by curcumin contributes to suppressing ER stress.

  20. A novel nuclear factor erythroid 2-related factor 2 (Nrf2) activator RS9 attenuates brain injury after ischemia reperfusion in mice.

    Science.gov (United States)

    Yamauchi, Keita; Nakano, Yusuke; Imai, Takahiko; Takagi, Toshinori; Tsuruma, Kazuhiro; Shimazawa, Masamitsu; Iwama, Toru; Hara, Hideaki

    2016-10-01

    Recanalization of occluded vessels leads to ischemia-reperfusion injury (IRI), with oxidative stress as one of the main causes of injury, despite the fact that recanalization therapy is the most effective treatment for ischemic stroke. The nuclear factor erythroid 2-related factor 2 (Nrf2) is one of the transcription factors which has an essential role in protection against oxidative stress. RS9 is a novel Nrf2 activator obtained from bardoxolone methyl (BARD), an Nrf2 activator that has already been tested in a clinical trial, using a biotransformation technique. RS9 has been reported to lead to higher Nrf2 activation and less cytotoxicity than BARD. In this study, we investigated the effects of RS9 on IRI. Mice were intraperitoneally treated immediately after 2h of transient middle cerebral artery occlusion (MCAO) with a vehicle solution or 0.2mg/kg of RS9. Post-onset treatment of RS9 attenuated the infarct volume and improved neurological deficits 22h after reperfusion. RS9 activated Nrf2 2 and 6h after reperfusion and activated heme oxygenase-1 at 6 and 22h after reperfusion. RS9 also attenuated the phosphorylation of NF-κB p65 2 and 6h after reperfusion. Finally, RS9 improved the survival rate and neurological deficits 7days after MCAO. Our results suggest that the activation of Nrf2 by RS9 has a neuroprotective effect, mediated by attenuating both oxidative stress and neuroinflammation, and that RS9 is an effective therapeutic candidate for the treatment of IRI. PMID:27474227

  1. Astrocytes Enhance Streptococcus suis-Glial Cell Interaction in Primary Astrocyte-Microglial Cell Co-Cultures.

    Science.gov (United States)

    Seele, Jana; Nau, Roland; Prajeeth, Chittappen K; Stangel, Martin; Valentin-Weigand, Peter; Seitz, Maren

    2016-06-13

    Streptococcus (S.) suis infections are the most common cause of meningitis in pigs. Moreover, S. suis is a zoonotic pathogen, which can lead to meningitis in humans, mainly in adults. We assume that glial cells may play a crucial role in host-pathogen interactions during S. suis infection of the central nervous system. Glial cells are considered to possess important functions during inflammation and injury of the brain in bacterial meningitis. In the present study, we established primary astrocyte-microglial cell co-cultures to investigate interactions of S. suis with glial cells. For this purpose, microglial cells and astrocytes were isolated from new-born mouse brains and characterized by flow cytometry, followed by the establishment of astrocyte and microglial cell mono-cultures as well as astrocyte-microglial cell co-cultures. In addition, we prepared microglial cell mono-cultures co-incubated with uninfected astrocyte mono-culture supernatants and astrocyte mono-cultures co-incubated with uninfected microglial cell mono-culture supernatants. After infection of the different cell cultures with S. suis, bacteria-cell association was mainly observed with microglial cells and most prominently with a non-encapsulated mutant of S. suis. A time-dependent induction of NO release was found only in the co-cultures and after co-incubation of microglial cells with uninfected supernatants of astrocyte mono-cultures mainly after infection with the capsular mutant. Only moderate cytotoxic effects were found in co-cultured glial cells after infection with S. suis. Taken together, astrocytes and astrocyte supernatants increased interaction of microglial cells with S. suis. Astrocyte-microglial cell co-cultures are suitable to study S. suis infections and bacteria-cell association as well as NO release by microglial cells was enhanced in the presence of astrocytes.

  2. Curcumin attenuates the release of pro-inflammatory cytokines in lipopolysaccharide-stimulated BV2 microglia

    Institute of Scientific and Technical Information of China (English)

    Cheng-yun JIN; Jae-dong LEE; Cheol PARK; Yung hyun CHOI; Gi-young KIM

    2007-01-01

    Aim: Pro-inflammatory mediators, such as prostaglandin E2 (PGE2) and nitric oxide(NO), and pro-inflammatory cytokines such as intedeukini(IL)- 1β, IL-6, and TNF-α, play pivotal roles in brain injuries. The anti-inflammatory properties are known to be associated with significant reductions in pro-inflammatory mediators in brain injuries. In the present study we investigate whether the effects of curcumin on the production of pro-inflammatory mediators in lipopolysaccharide (LPS)-stimu-lated BV2 microglia. Methods: Curcumin were administered and their effects on LPS-induced pro-inflammatory mediators were monitored by Western blotting and RT-PCR. Result: Curcumin significantly inhibited the release of NO, PGE2,and pro-inflammatory cytokines in a dose-dependent manner. Curcumin also attenuated the expressions of inducible NO synthase and cyclooxygenase-2 mRNA and protein levels. Moreover, curcumin suppressed NF-κB activation via the translocation of p65 into the nucleus. Our data also indicate that curcumin exerts anti-inflammatory properties by suppressing the transcription of proinflammatory cytokine genes through the NF-rd3 signaling pathway. Conclusion: Anti-inflam-matory properties of curcumin may be useful for treating the inflammatory and deleterious effects of microglial activation in response to LPS stimulation.

  3. [Reactive microglial changes in rat neocortex and hippocampus after exposure to acute perinatal hypoxia].

    Science.gov (United States)

    Khozhaĭ, L I; Otellin, V A

    2013-01-01

    The dynamics of reactive changes of a population density of microglial cells and the reversibility of their phenotypic forms were studied in the brain of neonatal rats at different time intervals after 1 hr-long exposure to acute normobaric hypoxia in the pressure chamber at the second postnatal day. Different areas of the neocortex (frontal, motor, somatosensory and visual) and of the hippocampus (CAI, CA3, CA4 and fascia dentata) were examined 1 hr, 3 hrs, 1 and 5 days after exposure to hypoxia. Microglial cells were demonstrated using an immunocytochemical staining with the monoclonal antibodies against Iba- 1 antigen. The results have shown that the reaction of microglia to acute hypoxia in both the neocortex and the hippocampus of the new-borns developed simultaneously and synchronously with the augmentation of cell death. The increase of a population density of amoeboid form of microglial cells in the brain areas studied was recorded already after 1 hour as a result of their migration from the subventricular region and the areas adjacent to large vessels from where they practically disappeared. The number of amoeboid microglial cells in this area has recovered rather quickly (in 3 hrs). The population densify of microglial cells, especially of amoeboid forms, sharply increased with the augmentation of cell death and remained unchanged for about 5 days.

  4. Phagocytosis-dependent and independent mechanisms underlie the microglial cell damage caused by carbon nanotube agglomerates.

    Science.gov (United States)

    Shigemoto-Mogami, Yukari; Hoshikawa, Kazue; Hirose, Akihiko; Sato, Kaoru

    2016-01-01

    Although carbon nanotubes (CNTs) are used in many fields, including energy, healthcare, environmental technology, materials, and electronics, the adverse effects of CNTs in the brain are poorly understood. In this study, we investigated the effects of CNTs on cultured microglia, as microglia are the first responders to foreign materials. We compared the effects of sonicated suspensions of 5 kinds of CNTs and their flow-through filtered with a 0.22 µm membrane filter on microglial viability. We found that sonicated suspensions caused microglial cell damage, but their flow-through did not. The number of microglial aggregates was well correlated with the extent of the damage. We also determined that the CNT agglomerates consisted of two groups: one was phagocytosed by microglia and caused microglial cell damage, and the other caused cell damage without phagocytosis. These results suggest that phagocytosis-dependent and independent mechanisms underlie the microglial cell damage caused by CNT agglomerates and it is important to conduct studies about the relationships between physical properties of nanomaterial-agglomerates and cell damage. PMID:27432236

  5. Minocycline attenuates brain tissue levels of TNF-α produced by neurons after prolonged hypothermic cardiac arrest in rats

    Science.gov (United States)

    Drabek, Tomas; Janata, Andreas; Wilson, Caleb D.; Stezoski, Jason; Janesko-Feldman, Keri; Tisherman, Samuel A.; Foley, Lesley M.; Verrier, Jonathan; Kochanek, Patrick M.

    2014-01-01

    Neuro-cognitive disabilities are a well-recognized complication of hypothermic circulatory arrest. We and others have reported that prolonged cardiac arrest (CA) produces neuronal death and microglial proliferation and activation that are only partially mitigated by hypothermia. Microglia, and possibly other cells, are suggested to elaborate tumor necrosis factor alpha (TNF-α) which can trigger neuronal death cascades and exacerbate edema after CNS insults. Minocycline is neuroprotective in some brain ischemia models in part by blunting the microglial response. We tested the hypothesis that minocycline would attenuate neuroinflammation as reflected by brain tissue levels of TNF-α after hypothermic CA in rats. Rats were subjected to rapid exsanguination, followed by a 6 min normothermic CA. Hypothermia (30 °C) was then induced by an aortic saline flush. After a total of 20 min CA, resuscitation was achieved via cardiopulmonary bypass (CPB). After 5 min reperfusion, minocycline (90 mg/kg; n=6) or vehicle (PBS; n=6) were given. Hypothermia (34 °C) was maintained for 6 h. Rats were sacrificed at 6 or 24 h. TNF-α was quantified (ELISA) in four brain regions (cerebellum, CEREB; cortex, CTX; hippocampus, HIP; striatum, STRI). Naïve rats (n=6) and rats subjected to the same anesthesia and CPB but no CA served as controls (n=6). Immunocytochemistry was used to localize TNF-α. Naïve rats and CPB controls had no detectable TNF-α in any brain region. CA markedly increased brain TNF-α. Regional differences were seen, with the highest TNF-α levels in striatum in CA groups (10-fold higher, P<0.05 vs. all other brain regions). TNF-α was undetectable at 24 h. Minocycline attenuated TNF-α levels in CTX, HIP and STRI (P<0.05). TNF-α showed unique co-localization with neurons. In conclusion, we report region-dependent early increases in brain TNF-α levels after prolonged hypothermic CA, with maximal increases in striatum. Surprisingly, TNF-α co-localized in neurons and

  6. Microglial migration mediated by ATP-induced ATP release from lysosomes

    Institute of Scientific and Technical Information of China (English)

    Ying Dou; Qing-ming Luo; Shumin Duan; Hang-jun Wu; Hui-quan Li; Song Qin; Yin-er Wang; Jing Li; Hui-fang Lou; Zhong Chen; Xiao-ming Li

    2012-01-01

    Microglia are highly motile cells that act as the main form of active immune defense in the central nervous system.Attracted by factors released from damaged cells,microglia are recruited towards the damaged or infected site,where they are involved in degenerative and regenerative responses and phagocytotic clearance of cell debris.ATP release from damaged neural tissues has been suggested to mediate the rapid extension of microglial process towards the site of injury.However,the mechanisms of the long-range migration of microglia remain to be clarified.Here,we found that lysosomes in microglia contain abundant ATP and exhibit Ca2+-dependent exocytosis in response to various stimuli.By establishing an efficient in vitro chemotaxis assay,we demonstrated that endogenously-released ATP from microglia triggered by local microinjection of ATPγS is critical for the long-range chemotaxis of microglia,a response that was significantly inhibited in microglia treated with an agent inducing iysosome osmodialysis or in cells derived from mice deficient in Rab 27a (ashen mice),a small GTPase required for the trafficking and exocytosis of secretory iysosomes.These results suggest that microglia respond to extracellular ATP by releasing ATP themselves through lysosomal exocytosis,thereby providing a positive feedback mechanism to generate a long-range extracellular signal for attracting distant microglia to migrate towards and accumulate at the site of injury.

  7. Microglial cytokine gene induction after irradiation is affected by morphologic differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Hayakawa, Kazushige; Borchardt, P.E.; Sakuma, Shirou; Ijichi, Akihiro; Tofilon, P.J. [Univ. of Texas (United States). M. D. Anderson Cancer Center; Niibe, Hideo

    1997-11-01

    Microglia are known to play an important role in the CNS cytokine network, and their response after irradiation may be associated with the development of radiation-induced tissue damage. Radiation effects on this cytokine network have not yet been elucidated. We investigated the effect of {gamma}-irradiation on microglia stimulated with Zymosan A and lipopolysaccharide (LPS), which alone induce the expression of some cytokines and neurotoxic products by microglial cells. In the resting condition (ramified microglia), radiation had no effect on the mRNA level corresponding to cytokines such as ILl{beta} or IL-6, although TGF-{beta}l mRNA was minimally enhanced by irradiation. However, in the activated microglia (amoeboid microglia) stimulated with Zymosan A, radiation-induced IL-6 mRNA expression was increased about two-fold in comparison with non-irradiation. IL-l{beta} was slightly induced by 2 Gy irradiation, but was not induced by higher doses. TGF-{beta}l mRNA was not enhanced by radiation following Zymosan stimulation. In the LPS-stimulated condition, IL-6 mRNA was induced only by 2 Gy of irradiation, but no change in the expression of other genes was detected. These results suggested that radiation exerted different effects on cytokine gene transcription in microglia depending on their morphological state. (author)

  8. Use of Activated Carbon in Packaging to Attenuate Formaldehyde-Induced and Formic Acid-Induced Degradation and Reduce Gelatin Cross-Linking in Solid Dosage Forms.

    Science.gov (United States)

    Colgan, Stephen T; Zelesky, Todd C; Chen, Raymond; Likar, Michael D; MacDonald, Bruce C; Hawkins, Joel M; Carroll, Sophia C; Johnson, Gail M; Space, J Sean; Jensen, James F; DeMatteo, Vincent A

    2016-07-01

    Formaldehyde and formic acid are reactive impurities found in commonly used excipients and can be responsible for limiting drug product shelf-life. Described here is the use of activated carbon in drug product packaging to attenuate formaldehyde-induced and formic acid-induced drug degradation in tablets and cross-linking in hard gelatin capsules. Several pharmaceutical products with known or potential vulnerabilities to formaldehyde-induced or formic acid-induced degradation or gelatin cross-linking were subjected to accelerated stability challenges in the presence and absence of activated carbon. The effects of time and storage conditions were determined. For all of the products studied, activated carbon attenuated drug degradation or gelatin cross-linking. This novel use of activated carbon in pharmaceutical packaging may be useful for enhancing the chemical stability of drug products or the dissolution stability of gelatin-containing dosage forms and may allow for the 1) extension of a drug product's shelf-life when the limiting attribute is a degradation product induced by a reactive impurity, 2) marketing of a drug product in hotter and more humid climatic zones than currently supported without the use of activated carbon, and 3) enhanced dissolution stability of products that are vulnerable to gelatin cross-linking.

  9. Use of Activated Carbon in Packaging to Attenuate Formaldehyde-Induced and Formic Acid-Induced Degradation and Reduce Gelatin Cross-Linking in Solid Dosage Forms.

    Science.gov (United States)

    Colgan, Stephen T; Zelesky, Todd C; Chen, Raymond; Likar, Michael D; MacDonald, Bruce C; Hawkins, Joel M; Carroll, Sophia C; Johnson, Gail M; Space, J Sean; Jensen, James F; DeMatteo, Vincent A

    2016-07-01

    Formaldehyde and formic acid are reactive impurities found in commonly used excipients and can be responsible for limiting drug product shelf-life. Described here is the use of activated carbon in drug product packaging to attenuate formaldehyde-induced and formic acid-induced drug degradation in tablets and cross-linking in hard gelatin capsules. Several pharmaceutical products with known or potential vulnerabilities to formaldehyde-induced or formic acid-induced degradation or gelatin cross-linking were subjected to accelerated stability challenges in the presence and absence of activated carbon. The effects of time and storage conditions were determined. For all of the products studied, activated carbon attenuated drug degradation or gelatin cross-linking. This novel use of activated carbon in pharmaceutical packaging may be useful for enhancing the chemical stability of drug products or the dissolution stability of gelatin-containing dosage forms and may allow for the 1) extension of a drug product's shelf-life when the limiting attribute is a degradation product induced by a reactive impurity, 2) marketing of a drug product in hotter and more humid climatic zones than currently supported without the use of activated carbon, and 3) enhanced dissolution stability of products that are vulnerable to gelatin cross-linking. PMID:27262203

  10. Pranlukast reduces neutrophil but not macrophage/microglial accumulation in brain after focal cerebral ischemia in mice

    Institute of Scientific and Technical Information of China (English)

    Li-sheng CHU; Er-qing WEI; Guo-liang YU; San-hua FANG; Yu ZHOU; Meng-ling WANG; Wei-ping ZHANG

    2006-01-01

    Aim:To determine whether pranlukast.a cysteinyl leukotriene receptor-1 antagonist,exerts an anti-inflammatory effect on focal cerebral ischemia in mice.Methods:Focal cerebral ischemia in mice was induced by permanent middle cerebral artery occlusion(MCAO).In addition to neurological deficits,infarct volume,degenerated neurons and endogenous IgG exudation,we detected accumulation of neutrophils and macrophage/microglia in the ischemic brain tissue 72 h after MCAO.Pranlukast was iP injected 30 min before and after MCAO.Results:Pranlukast significantly attenuated neurological deficits,infarct volume,neuron degeneration and IgG exudation.Importantly,pranlukast(0.01 and 0.1 mg/kg) inhibited myeloperoxidase-positive neutrophil,but not CDllb-positive macrophage/microglial accumulation in the ischemic cortical tissue.Conclusion:Pranlukast exerts an anti-inflammatory effect on focal cerebral ischemia in the subacute phase that is limited to neutrophil recruitment through the disrupted blood-brain barrier.

  11. Lanthanum Chloride Attenuates Osteoclast Formation and Function Via the Downregulation of Rankl-Induced Nf-κb and Nfatc1 Activities.

    Science.gov (United States)

    Jiang, Chuan; Shang, Jiangyinzi; Li, Zhe; Qin, An; Ouyang, Zhengxiao; Qu, Xinhua; Li, Haowei; Tian, Bo; Wang, Wengang; Wu, Chuanlong; Wang, Jinwu; Dai, Min

    2016-01-01

    The biological activities of lanthanum chloride (LaCl3 ) and the molecular mechanisms of action underlying its anti-inflammatory, anti-hyperphosphatemic, and osteoblast-enhancing effects have been studied previously, but less is known about the effects of LaCl3 on osteoclasts. The present study used in vivo and in vitro approaches to explore the effects of LaCl3 on osteoclasts and osteolysis. The results indicated that LaCl3 concentrations that were non-cytotoxic to mouse bone marrow-derived monocytes attenuated receptor activator of nuclear factor-κB ligand (RANKL)-stimulated osteoclastogenesis, bone resorption, mRNA expression of osteoclastogenic genes in these cells, including cathepsin K, calcitonin receptor, and tartrate-resistant acid phosphatase (TRAP). Further, LaCl3 inhibited RANKL-mediated activation of the nuclear factor-κB (NF-κB) signaling pathway, and downregulated mRNA and protein levels of nuclear factor of activated T-cells, cytoplasmic, calcineurin-dependent 1 (NFATc1), and c-fos. In vivo, LaCl3 attenuated titanium (Ti) particle-induced bone loss in a murine calvarial osteolysis model. Histological analyses revealed that LaCl3 ameliorated bone destruction and decreased the number of TRAP-positive osteoclasts in this model. These results demonstrated that LaCl3 inhibited osteoclast formation, function, and osteoclast-specific gene expression in vitro, and attenuated Ti particle-induced mouse calvarial osteolysis in vivo, where the inhibition of NF-κB signaling and downregulation of NFATc1 and c-fos played an important role.

  12. Minocycline Attenuates Iron Neurotoxicity in Cortical Cell Cultures

    OpenAIRE

    Chen-Roetling, Jing; Chen, Lifen; Regan, Raymond F.

    2009-01-01

    Iron neurotoxicity may contribute to the pathogenesis of intracerebral hemorrhage (ICH). The tetracycline derivative minocycline is protective in ICH models, due putatively to inhibition of microglial activation. Although minocycline also chelates iron, its effect on iron neurotoxicity has not been reported, and was examined in this study. Cortical cultures treated with 10 μM ferrous sulfate for 24h sustained loss of most neurons and an increase in malondialdehyde. Minocycline prevented this ...

  13. Pretreatment of rats with increased bioavailable berberine attenuates cerebral ischemia-reperfusion injury via down regulation of adenosine-5'monophosphate kinase activity.

    Science.gov (United States)

    Chen, Weijia; Wei, Shengnan; Yu, Yang; Xue, Huan; Yao, Fan; Zhang, Ming; Xiao, Jun; Hatch, Grant M; Chen, Li

    2016-05-15

    Berberine (BBR) exhibits multiple beneficial biological effects. However, poor bioavailability of BBR has limited its clinical application. We previously demonstrated that solid dispersion of BBR with sodium caprate (HGSD) remarkably improves its bioavailability. We examined whether this increased bioavailability of BBR could protect the brain from ischemia-reperfusion (IR) induced injury. Rats treated with HGSD, SC and saline for 7 days then subjected to cerebral ischemia reperfusion by middle cerebral artery occlusion for 2h followed 12h reperfusion. Neurological deficit scores, infarct size, SOD, MDA and NO levels were examined. P-AMPK, Bax, cleaved-Caspase-3 in brain was determined. To further probe for the mechanism of beneficial effect of HGSD, PC12 cells were incubated with serum from control or HGSD pretreated animals, incubated with 300μM H2O2 to induce apoptosis. Caspase-3 activity and cell apoptosis was evaluated. HGSD pretreatment significantly attenuated neurological deficit scores, reduced infarct size, increased SOD and decreased MDA and NO after cerebral IR injury compared to controls. Meanwhile, HGSD pretreatment significantly reduced expression of p-AMPK, Bax, cleaved-Caspase-3 after cerebral IR injury. Sodium caprate (100mg/kg/d) pretreatment alone did not exhibit any of these beneficial effects. PC12 cell apoptosis was attenuated when cells were cultured with HGSD serum compared to control. The presence of AMPK activator (AICAR) attenuated whereas AMPK inhibitor (Compound C) augmented the protective effect of HGSD serum on PC12 cell apoptosis.The results indicate that HGSD-pretreatment of rats protects the brain from ischemia-reperfusion injury and the mechanism is due to its anti-apoptotic effect mediated by decreased activation of AMPK. PMID:26957053

  14. Inhibition of Epidermal Growth Factor Receptor Improves Myelination and Attenuates Tissue Damage of Spinal Cord Injury.

    Science.gov (United States)

    Zhang, Si; Ju, Peijun; Tjandra, Editha; Yeap, Yeeshan; Owlanj, Hamed; Feng, Zhiwei

    2016-10-01

    Preventing demyelination and promoting remyelination of denuded axons are promising therapeutic strategies for spinal cord injury (SCI). Epidermal growth factor receptor (EGFR) inhibition was reported to benefit the neural functional recovery and the axon regeneration after SCI. However, its role in de- and remyelination of axons in injured spinal cord is unclear. In the present study, we evaluated the effects of EGFR inhibitor, PD168393 (PD), on the myelination in mouse contusive SCI model. We found that expression of myelin basic protein (MBP) in the injured spinal cords of PD treated mice was remarkably elevated. The density of glial precursor cells and oligodendrocytes (OLs) was increased and the cell apoptosis in lesions was attenuated after PD168393 treatment. Moreover, PD168393 treatment reduced both the numbers of OX42 + microglial cells and glial fibrillary acidic protein + astrocytes in damaged area of spinal cords. We thus conclude that the therapeutic effects of EGFR inhibition after SCI involves facilitating remyelination of the injured spinal cord, increasing of oligodendrocyte precursor cells and OLs, as well as suppressing the activation of astrocytes and microglia/macrophages. PMID:26883518

  15. Ligustrazine attenuates oxidative stress-induced activation of hepatic stellate cells by interrupting platelet-derived growth factor-β receptor-mediated ERK and p38 pathways

    International Nuclear Information System (INIS)

    Hepatic fibrosis represents a frequent event following chronic insult to trigger wound healing reactions with accumulation of extracellular matrix (ECM) in the liver. Activation of hepatic stellate cells (HSCs) is the pivotal event during liver fibrogenesis. Compelling evidence indicates that oxidative stress is concomitant with liver fibrosis irrespective of the underlying etiology. Natural antioxidant ligustrazine exhibits potent antifibrotic activities, but the mechanisms are poorly understood. Our studies were to investigate the ligustrazine effects on HSC activation stimulated by hydrogen peroxide (H2O2), an in vitro model mimicking the oxidative stress in liver fibrogenesis, and to elucidate the possible mechanisms. Our results demonstrated that H2O2 at 5 μM significantly stimulated HSC proliferation and expression of marker genes of HSC activation; whereas ligustrazine dose-dependently suppressed proliferation and induced apoptosis in H2O2-activated HSCs, and attenuated expression of fibrotic marker genes. Mechanistic investigations revealed that ligustrazine reduced platelet-derived growth factor-β receptor (PDGF-βR) expression and blocked the phosphorylation of extracellular regulated protein kinase (ERK) and p38 kinase, two downstream effectors of PDGF-βR. Further molecular evidence suggested that ligustrazine interruption of ERK and p38 pathways was dependent on the blockade of PDGF-βR and might be involved in ligustrazine reduction of fibrotic marker gene expression under H2O2 stimulation. Furthermore, ligustrazine modulated some proteins critical for HSC activation and ECM homeostasis in H2O2-stimulated HSCs. These data collectively indicated that ligustrazine could attenuate HSC activation caused by oxidative stress, providing novel insights into ligustrazine as a therapeutic option for hepatic fibrosis. Highlights: ► Ligustrazine inhibits oxidative stress-induced HSC activation. ► Ligustrazine reduces fibrotic marker genes in HSCs under

  16. Effects of chemokine (C–C motif) ligand 1 on microglial function

    International Nuclear Information System (INIS)

    Highlights: •CCR8, a specific receptor for CCL-1, was expressed on primary cultured microglia. •Expression of CCR-8 in microglia was upregulated in the presence of CCL-1. •CCL-1 increased motility, proliferation and phagocytosis of cultured microglia. •CCL-1promoted BDNF and IL-6 mRNA, and the release of NO from microglia. •CCL-1 activates microglia and may contribute to the development of neuropathic pain. -- Abstract: Microglia, which constitute the resident macrophages of the central nervous system (CNS), are generally considered as the primary immune cells in the brain and spinal cord. Microglial cells respond to various factors which are produced following nerve injury of multiple aetiologies and contribute to the development of neuronal disease. Chemokine (C–C motif) ligand 1 (CCL-1), a well-characterized chemokine secreted by activated T cells, has been shown to play an important role in neuropathic pain induced by nerve injury and is also produced in various cell types in the CNS, especially in dorsal root ganglia (DRG). However, the role of CCL-1 in the CNS and the effects on microglia remains unclear. Here we showed the multiple effects of CCL-1 on microglia. We first showed that CCR-8, a specific receptor for CCL-1, was expressed on primary cultured microglia, as well as on astrocytes and neurons, and was upregulated in the presence of CCL-1. CCL-1 at concentration of 1 ng/ml induced chemotaxis, increased motility at a higher concentration (100 ng/ml), and increased proliferation and phagocytosis of cultured microglia. CCL-1 also activated microglia morphologically, promoted mRNA levels for brain-derived neurotrophic factor (BDNF) and IL-6, and increased the release of nitrite from microglia. These indicate that CCL-1 has a role as a mediator in neuron-glia interaction, which may contribute to the development of neurological diseases, especially in neuropathic pain

  17. Effects of chemokine (C–C motif) ligand 1 on microglial function

    Energy Technology Data Exchange (ETDEWEB)

    Akimoto, Nozomi [Laboratory of Pathophysiology, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Ifuku, Masataka [Laboratory of Integrative Physiology, Graduate School of Medicine, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Mori, Yuki [Laboratory of Pathophysiology, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan); Noda, Mami, E-mail: noda@phar.kyushu-u.ac.jp [Laboratory of Pathophysiology, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582 (Japan)

    2013-07-05

    Highlights: •CCR8, a specific receptor for CCL-1, was expressed on primary cultured microglia. •Expression of CCR-8 in microglia was upregulated in the presence of CCL-1. •CCL-1 increased motility, proliferation and phagocytosis of cultured microglia. •CCL-1promoted BDNF and IL-6 mRNA, and the release of NO from microglia. •CCL-1 activates microglia and may contribute to the development of neuropathic pain. -- Abstract: Microglia, which constitute the resident macrophages of the central nervous system (CNS), are generally considered as the primary immune cells in the brain and spinal cord. Microglial cells respond to various factors which are produced following nerve injury of multiple aetiologies and contribute to the development of neuronal disease. Chemokine (C–C motif) ligand 1 (CCL-1), a well-characterized chemokine secreted by activated T cells, has been shown to play an important role in neuropathic pain induced by nerve injury and is also produced in various cell types in the CNS, especially in dorsal root ganglia (DRG). However, the role of CCL-1 in the CNS and the effects on microglia remains unclear. Here we showed the multiple effects of CCL-1 on microglia. We first showed that CCR-8, a specific receptor for CCL-1, was expressed on primary cultured microglia, as well as on astrocytes and neurons, and was upregulated in the presence of CCL-1. CCL-1 at concentration of 1 ng/ml induced chemotaxis, increased motility at a higher concentration (100 ng/ml), and increased proliferation and phagocytosis of cultured microglia. CCL-1 also activated microglia morphologically, promoted mRNA levels for brain-derived neurotrophic factor (BDNF) and IL-6, and increased the release of nitrite from microglia. These indicate that CCL-1 has a role as a mediator in neuron-glia interaction, which may contribute to the development of neurological diseases, especially in neuropathic pain.

  18. Baicalin Attenuates Hypoxia-Induced Pulmonary Arterial Hypertension to Improve Hypoxic Cor Pulmonale by Reducing the Activity of the p38 MAPK Signaling Pathway and MMP-9.

    Science.gov (United States)

    Yan, Shuangquan; Wang, Yiran; Liu, Panpan; Chen, Ali; Chen, Mayun; Yao, Dan; Xu, Xiaomei; Wang, Liangxing; Huang, Xiaoying

    2016-01-01

    Baicalin has a protective effect on hypoxia-induced pulmonary hypertension in rats, but the mechanism of this effect remains unclear. Thus, investigating the potential mechanism of this effect was the aim of the present study. Model rats that display hypoxic pulmonary hypertension and cor pulmonale under control conditions were successfully generated. We measured a series of indicators to observe the levels of pulmonary arterial hypertension, pulmonary arteriole remodeling, and right ventricular remodeling. We assessed the activation of p38 mitogen-activated protein kinase (MAPK) in the pulmonary arteriole walls and pulmonary tissue homogenates using immunohistochemistry and western blot analyses, respectively. The matrix metalloproteinase- (MMP-) 9 protein and mRNA levels in the pulmonary arteriole walls were measured using immunohistochemistry and in situ hybridization. Our results demonstrated that baicalin not only reduced p38 MAPK activation in both the pulmonary arteriole walls and tissue homogenates but also downregulated the protein and mRNA expression levels of MMP-9 in the pulmonary arteriole walls. This downregulation was accompanied by the attenuation of pulmonary hypertension, arteriole remodeling, and right ventricular remodeling. These results suggest that baicalin may attenuate pulmonary hypertension and cor pulmonale, which are induced by chronic hypoxia, by downregulating the p38 MAPK/MMP-9 pathway. PMID:27688788

  19. Overexpression of activin-A and -B in malignant mesothelioma – Attenuated Smad3 signaling responses and ERK activation promote cell migration and invasive growth

    International Nuclear Information System (INIS)

    Activin-A and activin-B, members of the TGF-β superfamily, are regulators of reproductive functions, inflammation and wound healing. These dimeric molecules regulate various cellular activities such as proliferation, migration and suvival. Malignant mesothelioma is an asbestos exposure related tumor affecting mainly pleura and it usually has a dismal prognosis. Here, we demonstrate that both activin-A and -B are abundantly expressed in mesothelioma tumor tissue as well as in cultured primary and established mesothelioma cells. Migratory and invasive mesothelioma cells were also found to have attenuated activation of the Smad2/3 pathway in response to activins. Migration and invasive growth of the cells in three-dimentional matrix was prevented by inhibition of activin activity using a soluble activin receptor 2B (sActR2B-Fc). This was associated with decreased ERK activity. Furthermore, migration and invasive growth was significantly inhibited by blocking ERK phosphorylation. Mesothelioma tumors are locally invasive and our results clearly suggest that acivins have a tumor-promoting function in mesothelioma through increasing expression and switching from canonical Smad3 pathway to non-canonical ERK pathway signaling. Blocking activin activity offers a new therapeutic approach for inhibition of mesothelioma invasive growth. - Highlights: • Activin-A and activin-B are highly expressed in mesothelioma. • Mesothelioma cell migration and invasive growth can be blocked with sActR2B. • Activin induced Smad3 activity is attenuated in invasive mesothelioma cells. • Activins induce ERK activity in mesothelioma cells

  20. Overexpression of activin-A and -B in malignant mesothelioma – Attenuated Smad3 signaling responses and ERK activation promote cell migration and invasive growth

    Energy Technology Data Exchange (ETDEWEB)

    Tamminen, Jenni A.; Yin, Miao [Research Programs Unit, Translational Cancer Biology, University of Helsinki (Finland); Transplantation Laboratory, Haartman Institute, University of Helsinki (Finland); Rönty, Mikko [Helsinki University Central Hospital Laboratory, Helsinki (Finland); Department of Pathology, University of Helsinki (Finland); Sutinen, Eva [Helsinki University Central Hospital Laboratory, Helsinki (Finland); Department of Medicine, Division of Pulmonary Medicine, University of Helsinki (Finland); Pasternack, Arja; Ritvos, Olli [Helsinki University Central Hospital Laboratory, Helsinki (Finland); Department of Bacteriology and Immunology, University of Helsinki (Finland); Myllärniemi, Marjukka [Transplantation Laboratory, Haartman Institute, University of Helsinki (Finland); Helsinki University Central Hospital Laboratory, Helsinki (Finland); Department of Medicine, Division of Pulmonary Medicine, University of Helsinki (Finland); Koli, Katri, E-mail: katri.koli@helsinki.fi [Research Programs Unit, Translational Cancer Biology, University of Helsinki (Finland); Transplantation Laboratory, Haartman Institute, University of Helsinki (Finland)

    2015-03-01

    Activin-A and activin-B, members of the TGF-β superfamily, are regulators of reproductive functions, inflammation and wound healing. These dimeric molecules regulate various cellular activities such as proliferation, migration and suvival. Malignant mesothelioma is an asbestos exposure related tumor affecting mainly pleura and it usually has a dismal prognosis. Here, we demonstrate that both activin-A and -B are abundantly expressed in mesothelioma tumor tissue as well as in cultured primary and established mesothelioma cells. Migratory and invasive mesothelioma cells were also found to have attenuated activation of the Smad2/3 pathway in response to activins. Migration and invasive growth of the cells in three-dimentional matrix was prevented by inhibition of activin activity using a soluble activin receptor 2B (sActR2B-Fc). This was associated with decreased ERK activity. Furthermore, migration and invasive growth was significantly inhibited by blocking ERK phosphorylation. Mesothelioma tumors are locally invasive and our results clearly suggest that acivins have a tumor-promoting function in mesothelioma through increasing expression and switching from canonical Smad3 pathway to non-canonical ERK pathway signaling. Blocking activin activity offers a new therapeutic approach for inhibition of mesothelioma invasive growth. - Highlights: • Activin-A and activin-B are highly expressed in mesothelioma. • Mesothelioma cell migration and invasive growth can be blocked with sActR2B. • Activin induced Smad3 activity is attenuated in invasive mesothelioma cells. • Activins induce ERK activity in mesothelioma cells.

  1. Early microglial colonization of the human forebrain and possible involvement in periventricular white-matter injury of preterm infants.

    Science.gov (United States)

    Verney, Catherine; Monier, Anne; Fallet-Bianco, Catherine; Gressens, Pierre

    2010-10-01

    Amoeboid microglial subpopulations visualized by antibodies against ionized calcium-binding adapter molecule 1, CD68, and CD45 enter the forebrain starting at 4.5 postovulatory or gestational weeks (gw). They penetrate the telencephalon and diencephalon via the meninges, choroid plexus, and ventricular zone. Early colonization by amoeboid microglia-macrophages is first restricted to the white matter, where these cells migrate and accumulate in patches at the junctions of white-matter pathways, such as the three junctions that the internal capsule makes with the thalamocortical projection, external capsule and cerebral peduncle, respectively. In the cerebral cortex anlage, migration is mainly radial and tangential towards the immature white matter, subplate layer, and cortical plate, whereas pial cells populate the prospective layer I. A second wave of microglial cells penetrates the brain via the vascular route at about 12-13 gw and remains confined to the white matter. Two main findings deserve emphasis. First, microglia accumulate at 10-12 gw at the cortical plate-subplate junction, where the first synapses are detected. Second, microglia accumulate in restricted laminar bands, most notably around 19-30 gw, at the axonal crossroads in the white matter (semiovale centre) rostrally, extending caudally in the immature white matter to the visual radiations. This accumulation of proliferating microglia is located at the site of white-matter injury in premature neonates. The spatiotemporal organization of microglia in the immature white and grey matter suggests that these cells may play active roles in developmental processes such as axonal guidance, synaptogenesis, and neurodevelopmental apoptosis as well as in injuries to the developing brain, in particular in the periventricular white-matter injury of preterm infants. PMID:20557401

  2. Accelerated microglial pathology is associated with Aβ plaques in mouse models of Alzheimer's disease

    DEFF Research Database (Denmark)

    Baron, Rona; Babcock, Alicia A; Nemirovsky, Anna;

    2014-01-01

    Microglia integrate within the neural tissue with a distinct ramified morphology through which they scan the surrounding neuronal network. Here, we used a digital tool for the quantitative morphometric characterization of fine cortical microglial structures in mice, and the changes they undergo...

  3. Microglia is activated by astrocytes in trimethyltin intoxication

    International Nuclear Information System (INIS)

    Microglia participates in most acute and chronic neuropathologies and its activation appears to involve interactions with neurons and other glial cells. Trimethyltin (TMT)-induced brain damage is a well-characterized model of neurodegeneration, in which microglial activation occurs before neuronal degeneration. The aim of this in vitro study was to investigate the role of astroglia in TMT-induced microgliosis by using nitric oxide (NO), inducible NO synthase (iNOS), and morphological changes as parameters for microglial activation. Our investigation discusses (a) whether microglial cells can be activated directly by TMT; (b) if astroglial cells are capable of triggering or modulating microglial activation; (c) how the morphology and survival of microglia and astrocytes are affected by TMT treatment; and (d) whether microglial-astroglial interactions depend on direct cell contact or on soluble factors. Our results show that microglia are more vulnerable to TMT than astrocytes are and cannot be activated directly by TMT with regard to the examined parameters. In bilayer coculture with viable astroglial cells, microglia produce NO in significant amounts at subcytotoxic concentrations of TMT (20 μmol/l). At these TMT concentrations, microglial cells in coculture convert into small round cells without cell processes, whereas flat, fibroblast-like astrocytes convert into thin process bearing stellate cells with a dense and compact cell body. We conclude that astrocytes trigger microglial activation after treatment with TMT, although the mechanisms of this interaction remain unknown

  4. The Attenuated Brucella abortus Strain 19 Invades, Persists in, and Activates Human Dendritic Cells, and Induces the Secretion of IL-12p70 but Not IL-23.

    Directory of Open Access Journals (Sweden)

    Mario Weinhold

    Full Text Available Bacterial vectors have been proposed as novel vaccine strategies to induce strong cellular immunity. Attenuated strains of Brucella abortus comprise promising vector candidates since they have the potential to induce strong CD4(+ and CD8(+ T-cell mediated immune responses in the absence of excessive inflammation as observed with other Gram-negative bacteria. However, some Brucella strains interfere with the maturation of dendritic cells (DCs, which is essential for antigen-specific T-cell priming. In the present study, we investigated the interaction of human monocyte-derived DCs with the smooth attenuated B. abortus strain (S 19, which has previously been employed successfully to vaccinate cattle.We first looked into the potential of S19 to hamper the cytokine-induced maturation of DCs; however, infected cells expressed CD25, CD40, CD80, and CD86 to a comparable extent as uninfected, cytokine-matured DCs. Furthermore, S19 activated DCs in the absence of exogeneous stimuli, enhanced the expression of HLA-ABC and HLA-DR, and was able to persist intracellularly without causing cytotoxicity. Thus, DCs provide a cellular niche for persisting brucellae in vivo as a permanent source of antigen. S19-infected DCs produced IL-12/23p40, IL-12p70, and IL-10, but not IL-23. While heat-killed bacteria also activated DCs, soluble mediators were not involved in S19-induced activation of human DCs. HEK 293 transfectants revealed cellular activation by S19 primarily through engagement of Toll-like receptor (TLR2.Thus, as an immunological prerequisite for vaccine efficacy, B. abortus S19 potently infects and potently activates (most likely via TLR2 human DCs to produce Th1-promoting cytokines.

  5. The Attenuated Brucella abortus Strain 19 Invades, Persists in, and Activates Human Dendritic Cells, and Induces the Secretion of IL-12p70 but Not IL-23

    Science.gov (United States)

    Weinhold, Mario; Eisenblätter, Martin; Jasny, Edith; Fehlings, Michael; Finke, Antje; Gayum, Hermine; Rüschendorf, Ursula; Renner Viveros, Pablo; Moos, Verena; Allers, Kristina; Schneider, Thomas; Schaible, Ulrich E.; Schumann, Ralf R.; Mielke, Martin E.; Ignatius, Ralf

    2013-01-01

    Background Bacterial vectors have been proposed as novel vaccine strategies to induce strong cellular immunity. Attenuated strains of Brucella abortus comprise promising vector candidates since they have the potential to induce strong CD4+ and CD8+ T-cell mediated immune responses in the absence of excessive inflammation as observed with other Gram-negative bacteria. However, some Brucella strains interfere with the maturation of dendritic cells (DCs), which is essential for antigen-specific T-cell priming. In the present study, we investigated the interaction of human monocyte-derived DCs with the smooth attenuated B. abortus strain (S) 19, which has previously been employed successfully to vaccinate cattle. Methodology/Principal findings We first looked into the potential of S19 to hamper the cytokine-induced maturation of DCs; however, infected cells expressed CD25, CD40, CD80, and CD86 to a comparable extent as uninfected, cytokine-matured DCs. Furthermore, S19 activated DCs in the absence of exogeneous stimuli, enhanced the expression of HLA-ABC and HLA-DR, and was able to persist intracellularly without causing cytotoxicity. Thus, DCs provide a cellular niche for persisting brucellae in vivo as a permanent source of antigen. S19-infected DCs produced IL-12/23p40, IL-12p70, and IL-10, but not IL-23. While heat-killed bacteria also activated DCs, soluble mediators were not involved in S19-induced activation of human DCs. HEK 293 transfectants revealed cellular activation by S19 primarily through engagement of Toll-like receptor (TLR)2. Conclusions/Significance Thus, as an immunological prerequisite for vaccine efficacy, B. abortus S19 potently infects and potently activates (most likely via TLR2) human DCs to produce Th1-promoting cytokines. PMID:23805193

  6. Immunity to Schistosoma mansoni in guinea-pigs vaccinated with radiation-attenuated cercariae. T-cell activation of macrophages for larval killing

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, J.R.; McLaren, D.J.

    1988-02-01

    This study addresses macrophage activation in guinea-pigs vaccinated with radiation-attenuated cercariae of Schistosom mansoni. Peritoneal exudate macrophages elicited in vaccinated animals by mineral oil injection were activated to kill larval schistosomes in vitro. Killing efficiency is dependent upon the cell:target ratio employed and is enhanced by, but is not strictly dependent on, the presence of specific antibodies. Macrophages co-cultured with parasites release superoxide radicals and hydrogen peroxide, but the use of inhibitors has shown that neither of these reactive oxygen intermediates are the causal agents of cellular cytotoxicity in this system. Oil-elicited macrophages from naive guinea-pigs do not show comparable activation; they can, however, be activated in vitro by incubation with culture supernatant fluids from schistosome antigen-stimulated spleen, or lymph node cells harvested from vaccinated guinea-pigs. Naive macrophages activated in this way kill schistosomula in vitro and release the activation markers IL-l and superoxide anion. The macrophage-activating factor (MAF) present in spleen cell culture supernatant fluids has a MW of 35,000-55,000, but does not have the chemical characteristics of gamma-interferon.

  7. A novel thiol compound, N-acetylcysteine amide, attenuates allergic airway disease by regulating activation of NF-kappaB and hypoxia-inducible factor-1alpha.

    Science.gov (United States)

    Lee, Kyung Sun; Kim, So Ri; Park, Hee Sun; Park, Seoung Ju; Min, Kyung Hoon; Lee, Ka Young; Choe, Yeong Hun; Hong, Sang Hyun; Han, Hyo Jin; Lee, Young Rae; Kim, Jong Suk; Atlas, Daphne; Lee, Yong Chul

    2007-12-31

    Reactive oxygen species (ROS) play an important role in the pathogenesis of airway inflammation and hyperresponsiveness. Recent studies have demonstrated that antioxidants are able to reduce airway inflammation and hyperreactivity in animal models of allergic airway disease. A newly developed antioxidant, small molecular weight thiol compound, N-acetylcysteine amide (AD4) has been shown to increase cellular levels of glutathione and to attenuate oxidative stress related disorders such as Alzheimer's disease, Parkinson's disease, and multiple sclerosis. However, the effects of AD4 on allergic airway disease such as asthma are unknown. We used ovalbumin (OVA)-inhaled mice to evaluate the role of AD4 in allergic airway disease. In this study with OVA-inhaled mice, the increased ROS generation, the increased levels of Th2 cytokines and VEGF, the increased vascular permeability, the increased mucus production, and the increased airway resistance in the lungs were significantly reduced by the administration of AD4. We also found that the administration of AD4 decreased the increases of the NF-kappaB and hypoxia-inducible factor-1alpha (HIF-1alpha) levels in nuclear protein extracts of lung tissues after OVA inhalation. These results suggest that AD4 attenuates airway inflammation and hyperresponsiveness by regulating activation of NF-kappaB and HIF-1alpha as well as reducing ROS generation in allergic airway disease.

  8. A novel thiol compound, N-acetylcysteine amide, attenuates allergic airway disease by regulating activation of NF-kappaB and hypoxia-inducible factor-1alpha.

    Science.gov (United States)

    Lee, Kyung Sun; Kim, So Ri; Park, Hee Sun; Park, Seoung Ju; Min, Kyung Hoon; Lee, Ka Young; Choe, Yeong Hun; Hong, Sang Hyun; Han, Hyo Jin; Lee, Young Rae; Kim, Jong Suk; Atlas, Daphne; Lee, Yong Chul

    2007-12-31

    Reactive oxygen species (ROS) play an important role in the pathogenesis of airway inflammation and hyperresponsiveness. Recent studies have demonstrated that antioxidants are able to reduce airway inflammation and hyperreactivity in animal models of allergic airway disease. A newly developed antioxidant, small molecular weight thiol compound, N-acetylcysteine amide (AD4) has been shown to increase cellular levels of glutathione and to attenuate oxidative stress related disorders such as Alzheimer's disease, Parkinson's disease, and multiple sclerosis. However, the effects of AD4 on allergic airway disease such as asthma are unknown. We used ovalbumin (OVA)-inhaled mice to evaluate the role of AD4 in allergic airway disease. In this study with OVA-inhaled mice, the increased ROS generation, the increased levels of Th2 cytokines and VEGF, the increased vascular permeability, the increased mucus production, and the increased airway resistance in the lungs were significantly reduced by the administration of AD4. We also found that the administration of AD4 decreased the increases of the NF-kappaB and hypoxia-inducible factor-1alpha (HIF-1alpha) levels in nuclear protein extracts of lung tissues after OVA inhalation. These results suggest that AD4 attenuates airway inflammation and hyperresponsiveness by regulating activation of NF-kappaB and HIF-1alpha as well as reducing ROS generation in allergic airway disease. PMID:18160846

  9. Activation of sonic hedgehog signaling attenuates oxidized low-density lipoprotein-stimulated brain microvascular endothelial cells dysfunction in vitro.

    Science.gov (United States)

    Jiang, Xiu-Long; Chen, Ting; Zhang, Xu

    2015-01-01

    The study was performed to investigate the role of sonic hedgehog (SHH) in the oxidized low-density lipoprotein (oxLDL)-induced blood-brain barrier (BBB) disruption. The primary mouse brain microvascular endothelial cells (MBMECs) were exposed to oxLDL. The results indicated that treatment of MBMECs with oxLDL decreased the cell viability, and oxidative stress was involved in oxLDL-induce MBMECs dysfunction with increasing intracellular ROS and MDA formation as well as decreasing NO release and eNOS mRNA expression. In addition, SHH signaling components, such as SHH, Smo and Gli1, mRNA and protein levels were significantly decreased after incubation with increasing concentrations of oxLDL. Treatment with oxLDL alone or SHH loss-of-function significantly increased the permeability of MBMECs, and overexpression of SHH attenuated oxLDL-induced elevation of permeability in MBMECs. Furthermore, SHH gain-of-function could reverse oxLDL-induced apoptosis through inhibition caspase3 and caspase8 levels in MBMECs. Taken together, these results demonstrated that the suppression of SHH in MBMECs might contribute to the oxLDL-induced disruption of endothelial barrier. However, the overexpression of SHH could reverse oxLDL-induced endothelial cells dysfunction in vitro. PMID:26722472

  10. Dioscin alleviates alcoholic liver fibrosis by attenuating hepatic stellate cell activation via the TLR4/MyD88/NF-κB signaling pathway

    Science.gov (United States)

    Liu, Min; Xu, Youwei; Han, Xu; Yin, Lianhong; Xu, Lina; Qi, Yan; Zhao, Yanyan; Liu, Kexin; Peng, Jinyong

    2015-01-01

    The present work aimed to investigate the activities and underlying mechanisms of dioscin against alcoholic liver fibrosis (ALF). In vivo liver fibrosis in mice was induced by an alcoholic liquid diet, and in vitro studies were performed on activated HSC-T6 and LX2 cells treated with lipopolysaccharide. Our results showed that dioscin significantly attenuated hepatic stellate cells (HSCs) activation, improved collagen accumulation, and attenuated inflammation through down-regulating the levels of myeloid differentiation factor 88 (MyD88), nuclear factor κB (NF-κB), interleukin (IL)-1, IL-6 and tumour necrosis factor-α by decreasing Toll-like receptor (TLR)4 expression both in vivo and in vitro. TLR4 overexpression was also decreased by dioscin, leading to the markedly down-regulated levels of MyD88, NF-κB, transforming growth factor-β1 (TGF-β1), α-smooth muscle actin (α-SMA) and type I collagen (COL1A1) in cultured HSCs. Suppression of cellular MyD88 by ST2825 or abrogation of NF-κB by pyrrolidine dithiocarbamate eliminated the inhibitory effects of dioscin on the levels of TGF-β1, α-SMA and COL1A1. In a word, dioscin exhibited potent effects against ALF via altering TLR4/MyD88/NF-κB signaling pathway, which provided novel insights into the mechanisms of this compound as an antifibrogenic candidate for the treatment of ALF in the future. PMID:26655640

  11. Ligustrazine attenuates oxidative stress-induced activation of hepatic stellate cells by interrupting platelet-derived growth factor-β receptor-mediated ERK and p38 pathways

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Feng [Department of Clinical Pharmacy, College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210029 (China); Ni, Chunyan [Department of Clinical Pharmacy, College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210029 (China); The First People' s Hospital of Changzhou, Changzhou 213003 (China); Kong, Desong; Zhang, Xiaoping; Zhu, Xiaojing; Chen, Li [Department of Clinical Pharmacy, College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210029 (China); Lu, Yin [Department of Clinical Pharmacy, College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210029 (China); Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing 210046 (China); National First-Class Key Discipline for Traditional Chinese Medicine of Nanjing University of Chinese Medicine, Nanjing 210046 (China); Zheng, Shizhong, E-mail: nytws@163.com [Department of Clinical Pharmacy, College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210029 (China); Jiangsu Key Laboratory for Pharmacology and Safety Evaluation of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing 210046 (China); National First-Class Key Discipline for Traditional Chinese Medicine of Nanjing University of Chinese Medicine, Nanjing 210046 (China)

    2012-11-15

    Hepatic fibrosis represents a frequent event following chronic insult to trigger wound healing reactions with accumulation of extracellular matrix (ECM) in the liver. Activation of hepatic stellate cells (HSCs) is the pivotal event during liver fibrogenesis. Compelling evidence indicates that oxidative stress is concomitant with liver fibrosis irrespective of the underlying etiology. Natural antioxidant ligustrazine exhibits potent antifibrotic activities, but the mechanisms are poorly understood. Our studies were to investigate the ligustrazine effects on HSC activation stimulated by hydrogen peroxide (H{sub 2}O{sub 2}), an in vitro model mimicking the oxidative stress in liver fibrogenesis, and to elucidate the possible mechanisms. Our results demonstrated that H{sub 2}O{sub 2} at 5 μM significantly stimulated HSC proliferation and expression of marker genes of HSC activation; whereas ligustrazine dose-dependently suppressed proliferation and induced apoptosis in H{sub 2}O{sub 2}-activated HSCs, and attenuated expression of fibrotic marker genes. Mechanistic investigations revealed that ligustrazine reduced platelet-derived growth factor-β receptor (PDGF-βR) expression and blocked the phosphorylation of extracellular regulated protein kinase (ERK) and p38 kinase, two downstream effectors of PDGF-βR. Further molecular evidence suggested that ligustrazine interruption of ERK and p38 pathways was dependent on the blockade of PDGF-βR and might be involved in ligustrazine reduction of fibrotic marker gene expression under H{sub 2}O{sub 2} stimulation. Furthermore, ligustrazine modulated some proteins critical for HSC activation and ECM homeostasis in H{sub 2}O{sub 2}-stimulated HSCs. These data collectively indicated that ligustrazine could attenuate HSC activation caused by oxidative stress, providing novel insights into ligustrazine as a therapeutic option for hepatic fibrosis. Highlights: ► Ligustrazine inhibits oxidative stress-induced HSC activation.

  12. Panaxatriol Saponins Attenuated Oxygen-Glucose Deprivation Injury in PC12 Cells via Activation of PI3K/Akt and Nrf2 Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Yongliang Huang

    2014-01-01

    Full Text Available Panaxatriol saponins (PTS, the main components extracted from Panax notoginseng, have been shown to be efficacious in the prevention and treatment of cerebrovascular diseases in China. NF-E2-related factor 2 (Nrf2, a transcription factor regulating antioxidant and cytoprotective responses to oxidative stress, has received particular attention as a molecular target for pharmacological intervention of ischemic diseases. The aim of this study was to characterize the effect of PTS on the activation of Nrf2 signaling pathway and the potential role in its protective effect. We found that PTS induced heme oxygenase-1 (HO-1 expression in PC12 cells via activating Nrf2 signaling pathway. Phosphatidylinositol 3-kinase (PI3K/Akt kinase was involved in the upstream of this PTS activated pathway. Moreover, combination of the main components in PTS significantly enhanced the expression of Nrf2 mediated phase II enzymes. Importantly, the protective effect of PTS against oxygen-glucose deprivation-reperfusion (OGD-Rep induced cell death was significantly attenuated by PI3K inhibitor and antioxidant response element (ARE decoy oligonucleotides, suggesting that both PI3K/Akt and Nrf2 signaling pathway are essential during this protective process. Taken together, our results suggest that PTS may activate endogenous cytoprotective mechanism against OGD-Rep induced oxidative injury via the activation of PI3K/Akt and Nrf2 signaling pathway.

  13. HIF-1α signaling activation by post-ischemia treatment with astragaloside IV attenuates myocardial ischemia-reperfusion injury.

    Directory of Open Access Journals (Sweden)

    Jingwen Si

    Full Text Available In this study, we evaluated the effect of astragaloside IV (Ast IV post-ischemia treatment on myocardial ischemia-reperfusion (IR injury (IRI. We also examined whether hypoxia inducible factor-1α (HIF-1α and its downstream gene-inducible nitric oxide (NO synthase (iNOS play roles in the cardioprotective effect of Ast IV. Cultured cardiomyocytes and perfused isolated rat hearts were exposed to Ast IV during reperfusion in the presence or absence of the HIF-1α inhibitor 2-methoxyestradiol (2-MeOE2. The post-ischemia treatment with Ast IV protected cardiomyocytes from the apoptosis and death induced by simulated IRI (SIRI. Additionally, in cardiomyocytes, 2-MeOE2 and HIF-1α siRNA treatment each not only abolished the anti-apoptotic effect of post-ischemia treatment with Ast IV but also reversed the upregulation of HIF-1α and iNOS expression. Furthermore, after treatment with Ast IV, post-ischemic cardiac functional recovery and lactate dehydrogenase (LDH release in the coronary flow (CF were improved, and the myocardial infarct size was decreased. Moreover, the number of apoptotic cells was reduced, and the upregulation of the anti-apoptotic protein Bcl2 and downregulation of the pro-apoptotic protein Caspase3 were reversed. 2-MeOE2 reversed these effects of Ast IV on IR-injured hearts. These results suggest that post-ischemia treatment with Ast IV can attenuate IRI by upregulating HIF-1α expression, which transmits a survival signal to the myocardium.

  14. Involvement of PKA and HO-1 signaling in anti-inflammatory effects of surfactin in BV-2 microglial cells

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sun Young; Kim, Ji-Hee [Department of Molecular Biology, College of Natural Sciences, Pusan National University, Jangjeon-dong, Keumjeong-gu, Busan 609-735 (Korea, Republic of); Lee, Sang Joon [Department of Microbiology, College of Natural Sciences, Pusan National University, Jangjeon-dong, Keumjeong-gu, Busan 609-735 (Korea, Republic of); Kim, YoungHee, E-mail: yheekim@pusan.ac.kr [Department of Molecular Biology, College of Natural Sciences, Pusan National University, Jangjeon-dong, Keumjeong-gu, Busan 609-735 (Korea, Republic of)

    2013-04-01

    Surfactin, one of the most powerful biosurfactants, is a bacterial cyclic lipopeptide. Here, we investigated the anti-neuroinflammatory properties of surfactin in lipoteichoic acid (LTA)-stimulated BV-2 microglial cells. Surfactin significantly inhibited excessive production of the pro-inflammatory mediators TNF-α, IL-1β, IL-6, monocyte chemoattractant protein-1 (MCP-1), prostaglandin E{sub 2} (PGE{sub 2}), nitric oxide (NO) and reactive oxygen species (ROS), and suppressed the expression of matrix metalloproteinase-9 (MMP-9), inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2). Subsequent mechanistic studies revealed that surfactin inhibited LTA-induced nuclear factor-kappaB (NF-κB) and signal transducer and activator of transcription-1 (STAT-1) activation. However, surfactin increases the phosphorylation of the STAT-3, a component of the homeostatic mechanism causing anti-inflammatory events. We also demonstrated that surfactin induces heme oxygenase-1 (HO-1) expression and nuclear factor-regulated factor-2 (Nrf-2) activation, and that the anti-inflammatory effects of surfactin are abrogated by small interfering RNA-mediated knock-down of HO-1 or Nrf-2. Interestingly, we found that surfactin increased the level of cAMP and induced phosphorylation of cAMP responsive element binding protein (CREB) in microglial cells. Furthermore, treatment with the protein kinase A (PKA) inhibitor, H-89, blocked HO-1 induction by surfactin and abolished surfactin's suppressive effects on ROS and NO production. These results indicate that HO-1 and its upstream effector, PKA, play a pivotal role in the anti-neuroinflammatory response of surfactin in LTA-stimulated microglia. Therefore, surfactin might have therapeutic potential for neuroprotective agents to treat inflammatory and neurodegenerative diseases. - Highlights: ► Surfactin inhibits proinflammatory mediator synthesis in LTA-activated BV-2 cells. ► Surfactin suppresses NF-κB and STAT-1, but potentiates

  15. Layer 5 Pyramidal Neurons’ Dendritic Remodeling and Increased Microglial Density in Primary Motor Cortex in a Murine Model of Facial Paralysis

    Directory of Open Access Journals (Sweden)

    Diana Urrego

    2015-01-01

    Full Text Available This work was aimed at characterizing structural changes in primary motor cortex layer 5 pyramidal neurons and their relationship with microglial density induced by facial nerve lesion using a murine facial paralysis model. Adult transgenic mice, expressing green fluorescent protein in microglia and yellow fluorescent protein in projecting neurons, were submitted to either unilateral section of the facial nerve or sham surgery. Injured animals were sacrificed either 1 or 3weeks after surgery. Two-photon excitation microscopy was then used for evaluating both layer 5 pyramidal neurons and microglia in vibrissal primary motor cortex (vM1. It was found that facial nerve lesion induced long-lasting changes in the dendritic morphology of vM1 layer 5 pyramidal neurons and in their surrounding microglia. Dendritic arborization of the pyramidal cells underwent overall shrinkage. Apical dendrites suffered transient shortening while basal dendrites displayed sustained shortening. Moreover, dendrites suffered transient spine pruning. Significantly higher microglial cell density was found surrounding vM1 layer 5 pyramidal neurons after facial nerve lesion with morphological bias towards the activated phenotype. These results suggest that facial nerve lesions elicit active dendrite remodeling due to pyramidal neuron and microglia interaction, which could be the pathophysiological underpinning of some neuropathic motor sequelae in humans.

  16. Anthocyanins Downregulate Lipopolysaccharide-Induced Inflammatory Responses in BV2 Microglial Cells by Suppressing the NF-κB and Akt/MAPKs Signaling Pathways

    Directory of Open Access Journals (Sweden)

    Yung Hyun Choi

    2013-01-01

    Full Text Available Anthocyanins are naturally occurring polyphenols that impart bright color to fruits, vegetables and plants and have a variety of protective properties, which have generally been attributed to their antioxidant capacity. However, little is known about the molecular mechanisms underlying anti-inflammatory effects of anthocyanins related to neurodegenerative diseases. Therefore, we determined whether anthocyanins isolated from black soybean seed coats would inhibit pro-inflammatory mediators and cytokines in lipopolysaccharide (LPS-stimulated murine BV2 microglial cells. Our results showed that anthocyanins significantly inhibited LPS-induced pro-inflammatory mediators, such as nitric oxide (NO and prostaglandin E2, and pro-inflammatory cytokines including tumor necrosis factor (TNF-α and interleukin (IL-1β, without significant cytotoxicity. Anthocyanins also downregulated excessive expression of inducible NO synthase, cyclooxygenase-2, TNF-α, and IL-1β in LPS-stimulated BV2 cells. Moreover, anthocyanins inhibited nuclear translocation of nuclear factor-kappa B (NF-κB by reducing inhibitor of NF-κB alpha degradation as well as phosphorylating extracellular signal-regulated kinase, c-Jun N-terminal kinase, p38 mitogen-activated protein kinase, and Akt. These findings suggest that anthocyanins may offer substantial therapeutic potential for treating inflammatory and neurodegenerative diseases accompanied by microglial activation.

  17. Layer 5 Pyramidal Neurons' Dendritic Remodeling and Increased Microglial Density in Primary Motor Cortex in a Murine Model of Facial Paralysis.

    Science.gov (United States)

    Urrego, Diana; Troncoso, Julieta; Múnera, Alejandro

    2015-01-01

    This work was aimed at characterizing structural changes in primary motor cortex layer 5 pyramidal neurons and their relationship with microglial density induced by facial nerve lesion using a murine facial paralysis model. Adult transgenic mice, expressing green fluorescent protein in microglia and yellow fluorescent protein in projecting neurons, were submitted to either unilateral section of the facial nerve or sham surgery. Injured animals were sacrificed either 1 or 3 weeks after surgery. Two-photon excitation microscopy was then used for evaluating both layer 5 pyramidal neurons and microglia in vibrissal primary motor cortex (vM1). It was found that facial nerve lesion induced long-lasting changes in the dendritic morphology of vM1 layer 5 pyramidal neurons and in their surrounding microglia. Dendritic arborization of the pyramidal cells underwent overall shrinkage. Apical dendrites suffered transient shortening while basal dendrites displayed sustained shortening. Moreover, dendrites suffered transient spine pruning. Significantly higher microglial cell density was found surrounding vM1 layer 5 pyramidal neurons after facial nerve lesion with morphological bias towards the activated phenotype. These results suggest that facial nerve lesions elicit active dendrite remodeling due to pyramidal neuron and microglia interaction, which could be the pathophysiological underpinning of some neuropathic motor sequelae in humans.

  18. Effects of caffeine and paracetamol alone or in combination with acetylsalicylic acid on prostaglandin E(2) synthesis in rat microglial cells.

    Science.gov (United States)

    Fiebich, B L; Lieb, K; Hüll, M; Aicher, B; van Ryn, J; Pairet, M; Engelhardt, G

    2000-08-23

    Paracetamol has mild analgesic and antipyretic properties and is, along with acetylsalicylic acid, one of the most popular "over the counter" analgesic agents. However, the mechanism underlying its clinical effects is unknown. Another drug whose mechanism of action is unknown is caffeine, which is often used in combination with other analgesics, augmenting their effect. We investigated the inhibitory effect of paracetamol and caffeine on lipopolysaccharide (LPS)-induced cyclooxygenase (COX)- and prostaglandin (PG)E(2)-synthesis in primary rat microglial cells and compared it with the effect of acetylsalicylic acid, salicylic acid, and dipyrone. Furthermore, combinations of these drugs were used to investigate a possible synergistic inhibitory effect on PGE(2)-synthesis. Both paracetamol (IC(50)=7.45 microM) and caffeine (IC(50)=42.5 microM) dose-dependently inhibited microglial PGE(2) synthesis. In combination with acetylsalicylic acid (IC(50)=3.12 microM), both substances augmented the inhibitory effect of acetylsalicylic acid on LPS-induced PGE(2)-synthesis. Whereas paracetamol inhibited only COX enzyme activity, caffeine also inhibited COX-2 protein synthesis. These results are compatible with the view that the clinical activity of paracetamol and caffeine is due to inhibition of COX. Furthermore, these results may help explain the clinical experience of an adjuvant analgesic effect of caffeine and paracetamol when combined with acetylsalicylic acid.

  19. Dexamethasone selectively suppresses microglial trophic responses to hippocampal deafferentation

    DEFF Research Database (Denmark)

    Woods, A G; Poulsen, F R; Gall, C M

    1999-01-01

    Hippocampal deafferentation increases the expression of insulin-like growth factor-1 by microglia, and of ciliary neurotrophic factor and basic fibroblast growth factor by astroglia in fields and periods of reactive axonal growth. Glucocorticoids attenuate lesion-induced hippocampal sprouting......, possibly by reducing trophic signals that stimulate growth. With an interest in this hypothesis, the present studies evaluated the influence of systemic treatment with the synthetic glucocorticoid dexamethasone on entorhinal lesion-induced increases in neurotrophic factor expression in young adult rat...... hippocampus. Daily dexamethasone injections almost completely blocked increases in insulin-like growth factor-1 messenger RNA content, but did not perturb increases in ciliary neurotrophic factor or basic fibroblast growth factor messenger RNA content, in the deafferented dentate gyrus molecular layer...

  20. Inhibitory effects of Blueberry Extract on the Production of Inflammatory Mediators in LPS-activated BV2 Microglia

    Science.gov (United States)

    Sustained microglial activation in the central nervous system (CNS) has been extensively investigated in age-related neurodegenerative diseases and has been postulated to lead to neuronal cell loss in these conditions. Recent studies have shown that anti-inflammatory drugs may suppress microglial ac...

  1. Inhibition of cerebrovascular raf activation attenuates cerebral blood flow and prevents upregulation of contractile receptors after subarachnoid hemorrhage

    DEFF Research Database (Denmark)

    Ansar, Saema; Maddahi, Aida; Edvinsson, Lars

    2011-01-01

    of mitogen-activated protein kinase (MAPK) of the extracellular signal-regulated kinase (ERK)1/2 signal pathway. We hypothesize that SAH initiates cerebrovascular ERK1/2 activation, resulting in receptor upregulation. The raf inhibitor will inhibit the molecular events upstream ERK1/2 and may provide...

  2. Diallylsulfide attenuates excessive collagen production and apoptosis in a rat model of bleomycin induced pulmonary fibrosis through the involvement of protease activated receptor-2

    International Nuclear Information System (INIS)

    Pulmonary fibrosis (PF) can be a devastating lung disease. It is primarily caused by inflammation leading to severe damage of the alveolar epithelial cells. The pathophysiology of PF is not yet been clearly defined, but studying lung parenchymal injury by involving reactive oxygen species (ROS) through the activation of protease activated receptor-2 (PAR-2) may provide promising results. PAR-2 is a G-protein coupled receptor is known to play an important role in the development of PF. In this study, we investigated the inhibitory role of diallylsulfide (DAS) against ROS mediated activation of PAR-2 and collagen production accompanied by epithelial cell apoptosis. Bleomycin induced ROS levels may prompt to induce the expression of PAR-2 as well as extracellular matrix proteins (ECM), such as MMP 2 and 9, collagen specific proteins HSP-47, α-SMA, and cytokines IL-6, and IL-8RA. Importantly DAS treatment effectively decreased the expression of all these proteins. The inhibitory effect of DAS on profibrotic molecules is mediated by blocking the ROS level. To identify apoptotic signaling as a mediator of PF induction, we performed apoptotic protein expression, DNA fragmentation analysis and ultrastructural details of the lung tissue were performed. DAS treatment restored all these changes to near normalcy. In conclusion, treatment of PF bearing rats with DAS results in amelioration of the ROS production, PAR-2 activation, ECM production, collagen synthesis and alveolar epithelial cell apoptosis during bleomycin induction. We attained the first evidence that treatment of DAS decreases the ROS levels and may provide a potential therapeutic effect attenuating bleomycin induced PF. - Highlights: • DAS inhibits PAR-2 activity; bleomycin stimulates PAR-2 activity. • Increase in PAR-2 activity is correlated with pulmonary fibrosis • DAS reduces pro-inflammatory activity linked to facilitating pulmonary fibrosis. • DAS inhibits apoptosis of alveolar epithelial cells

  3. Diallylsulfide attenuates excessive collagen production and apoptosis in a rat model of bleomycin induced pulmonary fibrosis through the involvement of protease activated receptor-2

    Energy Technology Data Exchange (ETDEWEB)

    Kalayarasan, Srinivasan, E-mail: kalaivasanbio@gmail.com; Sriram, Narayanan; Soumyakrishnan, Syamala; Sudhandiran, Ganapasam, E-mail: sudhandiran@yahoo.com

    2013-09-01

    Pulmonary fibrosis (PF) can be a devastating lung disease. It is primarily caused by inflammation leading to severe damage of the alveolar epithelial cells. The pathophysiology of PF is not yet been clearly defined, but studying lung parenchymal injury by involving reactive oxygen species (ROS) through the activation of protease activated receptor-2 (PAR-2) may provide promising results. PAR-2 is a G-protein coupled receptor is known to play an important role in the development of PF. In this study, we investigated the inhibitory role of diallylsulfide (DAS) against ROS mediated activation of PAR-2 and collagen production accompanied by epithelial cell apoptosis. Bleomycin induced ROS levels may prompt to induce the expression of PAR-2 as well as extracellular matrix proteins (ECM), such as MMP 2 and 9, collagen specific proteins HSP-47, α-SMA, and cytokines IL-6, and IL-8RA. Importantly DAS treatment effectively decreased the expression of all these proteins. The inhibitory effect of DAS on profibrotic molecules is mediated by blocking the ROS level. To identify apoptotic signaling as a mediator of PF induction, we performed apoptotic protein expression, DNA fragmentation analysis and ultrastructural details of the lung tissue were performed. DAS treatment restored all these changes to near normalcy. In conclusion, treatment of PF bearing rats with DAS results in amelioration of the ROS production, PAR-2 activation, ECM production, collagen synthesis and alveolar epithelial cell apoptosis during bleomycin induction. We attained the first evidence that treatment of DAS decreases the ROS levels and may provide a potential therapeutic effect attenuating bleomycin induced PF. - Highlights: • DAS inhibits PAR-2 activity; bleomycin stimulates PAR-2 activity. • Increase in PAR-2 activity is correlated with pulmonary fibrosis • DAS reduces pro-inflammatory activity linked to facilitating pulmonary fibrosis. • DAS inhibits apoptosis of alveolar epithelial cells.

  4. Attenuation of β-Amyloid-Induced Oxidative Cell Death by Sulforaphane via Activation of NF-E2-Related Factor 2

    Directory of Open Access Journals (Sweden)

    Chan Lee

    2013-01-01

    Full Text Available β-amyloid peptide (Aβ, a major component of senile plaques, plays important roles in neuropathology of Alzheimer's disease (AD. An array of in vitro and in vivo data indicates that Aβ-induced neuronal death is mediated by oxidative stress. In this study, we aimed to investigate effects of sulforaphane (SUL, an isothiocyanate in cruciferous vegetables, on Aβ-induced oxidative cell death in SH-SY5Y cells. Cells treated with Aβ25–35 exhibited decreased cell viability and underwent apoptosis as determined by MTT assay and TUNEL, respectively. Aβ25–35-induced cytotoxicity and apoptotic characteristics such as activation of c-JNK, dissipation of mitochondrial membrane potential, altered expression of Bcl-2 family proteins, and DNA fragmentation were effectively attenuated by SUL pretreatment. The antiapoptotic activity of SUL seemed to be mediated by inhibition of intracellular accumulation of reactive oxygen species and oxidative damages. SUL exerted antioxidant potential by upregulating expression of antioxidant enzymes including γ-glutamylcysteine ligase, NAD(PH:quinone oxidoreductase-1, and heme oxygenase-1 via activation of NF-E2-related factor 2(Nrf2. The protective effect of SUL against Aβ25–35-induced apoptotic cell death was abolished by siRNA of Nrf2. Taken together, the results suggest that pharmacologic activation of Nrf2 signaling pathway by SUL might be a practical prevention and/or protective treatment for the management of AD.

  5. Date syrup-derived polyphenols attenuate angiogenic responses and exhibits anti-inflammatory activity mediated by vascular endothelial growth factor and cyclooxygenase-2 expression in endothelial cells.

    Science.gov (United States)

    Taleb, Hajer; Morris, R Keith; Withycombe, Cathryn E; Maddocks, Sarah E; Kanekanian, Ara D

    2016-07-01

    Bioactive components such as polyphenols, present in many plants, are purported to have anti-inflammatory and antiangiogenic properties. Date syrup, produced from date fruit of the date palm tree, has traditionally been used to treat a wide range of diseases with etiologies involving angiogenesis and inflammation. It was hypothesized that polyphenols in date syrup reduce angiogenic responses such as cell migration, tube formation, and matrix metalloproteinase activity in an inflammatory model by exhibiting anti-inflammatory activity mediated by vascular endothelial growth factor (VEGF) and the prostaglandin enzyme cyclooxygenase-2 (COX-2) in endothelial cells. Date syrup polyphenols at 60 and 600μg/mL reduced inflammation and suppressed several stages of angiogenesis, including endothelial cell migration, invasion, matrix metalloproteinase activity, and tube formation, without evidence of cytotoxicity. VEGF and COX-2 expression induced by tumor necrosis factor-alpha at both gene expression and protein level was significantly reduced by date syrup polyphenols in comparison to untreated cells. In conclusion, polyphenols in date syrup attenuated angiogenic responses and exhibited anti-inflammatory activity mediated by VEGF and COX-2 expression in endothelial cells. PMID:27333954

  6. Inhibition of spinal UCHL1 attenuates pain facilitation in a cancer-induced bone pain model by inhibiting ubiquitin and glial activation

    Science.gov (United States)

    Cheng, Wei; Chen, Yuan-Li; Wu, Liang; Miao, Bei; Yin, Qin; Wang, Jin-Feng; Fu, Zhi-Jian

    2016-01-01

    The present study examined alterations of spinal ubiquitin C-terminal hydrolase L1 (UCHL1), ubiquitin expression and glial activation in the cancer-induced bone pain rats. Furthermore, whether inhibition of spinal UCHL1 could alleviate cancer-induced bone pain was observed. The CIBP model was established by intrathecal Walker 256 mammary gland carcinoma cells in SD rats. The rats of CIBP developed significant pain facilitation in the Von Frey test. Double immunofluorescence analyses revealed that in the spines of CIBP rats, ubiquitin co-localized with NeuN, Iba-1 or GFAP; UCHL1 and NeuN were co-expressed and UCHL1 also co-localized with ubiquitin. The CIBP model induced up-regulation of ubiquitin and UCHL1 in the spines, as well as glial activation. Inhibition of spinal UCHL1 attenuated pain facilitation by down-regulation of ubiquitin expression and glial activation. in the CIBP rats. Our data suggests that UCHL1/ubiquitin distributed and increased in the spines of CIBP rats, that glial activation also increased in the CIBP model and that inhibition of spinal UCHL1 may be an effective method to alleviate cancer-induced bone pain. PMID:27508024

  7. Two-dimensional zymography differentiates gelatinase isoforms in stimulated microglial cells and in brain tissues of acute brain injuries.

    Science.gov (United States)

    Chen, Shanyan; Meng, Fanjun; Chen, Zhenzhou; Tomlinson, Brittany N; Wesley, Jennifer M; Sun, Grace Y; Whaley-Connell, Adam T; Sowers, James R; Cui, Jiankun; Gu, Zezong

    2015-01-01

    Excessive activation of gelatinases (MMP-2/-9) is a key cause of detrimental outcomes in neurodegenerative diseases. A single-dimension zymography has been widely used to determine gelatinase expression and activity, but this method is inadequate in resolving complex enzyme isoforms, because gelatinase expression and activity could be modified at transcriptional and posttranslational levels. In this study, we investigated gelatinase isoforms under in vitro and in vivo conditions using two-dimensional (2D) gelatin zymography electrophoresis, a protocol allowing separation of proteins based on isoelectric points (pI) and molecular weights. We observed organomercuric chemical 4-aminophenylmercuric acetate-induced activation of MMP-2 isoforms with variant pI values in the conditioned medium of human fibrosarcoma HT1080 cells. Studies with murine BV-2 microglial cells indicated a series of proform MMP-9 spots separated by variant pI values due to stimulation with lipopolysaccharide (LPS). The MMP-9 pI values were shifted after treatment with alkaline phosphatase, suggesting presence of phosphorylated isoforms due to the proinflammatory stimulation. Similar MMP-9 isoforms with variant pI values in the same molecular weight were also found in mouse brains after ischemic and traumatic brain injuries. In contrast, there was no detectable pI differentiation of MMP-9 in the brains of chronic Zucker obese rats. These results demonstrated effective use of 2D zymography to separate modified MMP isoforms with variant pI values and to detect posttranslational modifications under different pathological conditions.

  8. Inhibition of p38 mitogen-activated protein kinase attenuates experimental autoimmune hepatitis: Involvement of nuclear factor kappa B

    Institute of Scientific and Technical Information of China (English)

    Xiong Ma; Yi-Tao Jia; De-Kai Qiu

    2007-01-01

    AIM: To investigate the role of p38 mitogen-activated protein kinase (p38MAPK) in murine experimental autoimmune hepatitis (EAH).METHODS: To induce EAH, the syngeneic S-100 antigen emulsified in complete Freud's adjuvant was injected intraperitoneally into adult male C57BI/6 mice. Liver injury was assessed by serum ALT and liver histology.The expression and activity of p38 MAPK were measured by Western blot and kinase activity assays. In addition,DNA binding activities of nuclear factor kappa B (NF-κB)were analyzed by electrophoretic mobility shift assay. The effects of SB203580, a specific p38 MAPK inhibitor, on liver injuries and expression of proinflammatory cytokines (interferon-γ, IL-12, IL-1β and TNF-α) were observed.RESULTS: The activity of p38 MAPK and NF-κB was increased and reached its peak 14 or 21 d after the first syngeneic S-100 administration. Inhibition of p38 MAPK activation by SB203580 decreased the activation of NF-κB and the expression of proinflammatory cytokines.Moreover, hepatic injuries were improved significantly after SB203580 administration.CONCLUSION: p38 MAPK and NF-κB play an important role in an animal model of autoimmune hepatitis (AIH)induced by autoantigens.

  9. Grapefruit-seed extract attenuates ethanol-and stress-induced gastric lesions via activation of prostaglandin, nitric oxide and sensory nerve pathways

    Institute of Scientific and Technical Information of China (English)

    Tomasz Brzozowski; Peter C Konturek; Danuta Drozdowicz; Stanislaw J Konturek; Oxana Zayachivska; Robert Pajdo; Slawomir Kwiecien; Wieslaw W Pawlik; Eckhart G Hahn

    2005-01-01

    AIM: Grapefruit-seed extract (GSE) containing flavonoids, possesses antibacterial and antioxidative properties but whether it influences the gastric defense mechanism and gastroprotection against ethanol- and stress-induced gastric lesions remains unknown.METHODS: We compared the effects of GSE on gastric mucosal lesions induced in rats by topical application of 100% ethanol or 3.5 h of water immersion and restraint stress (WRS) with or without (A) inhibition of cyclooxygenase (COX)-1 activity by indomethacin and rofecoxib, the selective COX-2 inhibitor, (B) suppression of NO-synthase with L-NNA (20 mg/kg ip), and (C) inactivation by capsaicin (125 mg/kg sc) of sensory nerves with or without intragastric (ig) pretreatment with GSE applied 30 min prior to ethanol or WRS. One hour after ethanol and 3.5 h after the end of WRS, the number and area of gastric lesions were measured by planimetry, the gastric bloodflow (GBF) was assessed by H2-gas clearance technique and plasma gastrin levels and the gastric mucosal generation of PGE2, superoxide dismutase (SOD) activity and malonyldialdehyde (MDA) concentration, as an index of lipid peroxidation were determined.RESULTS: Ethanol and WRS caused gastric lesions accompanied by the significant fall in the GBF and SOD activity and the rise in the mucosal MDA content.Pretreatment with GSE (8-64 mg/kg i g) dosedependently attenuated gastric lesions induced by 100% ethanol and WRS; the dose reducing these lesions by 50% (ID50) was 25 and 36 mg/kg, respectively, and this protective effect was similar to that obtained with methyl PGE2 analog (5 μg/kg i g). GSE significantly raised the GBF, mucosal generation of PGE2, SOD activity and plasma gastrin levels while attenuating MDA content.Inhibition of PGE2 generation with indomethacin or rofecoxib and suppression of NO synthase by L-NNA or capsaicin denervation reversed the GSE-induced protection and the accompanying hyperemia. Cotreatment of exogenous calcitonine gene

  10. Telomere dysfunction reduces microglial numbers without fully inducing an aging phenotype

    DEFF Research Database (Denmark)

    Khan, Asif Manzoor; Babcock, Alicia; Saeed, Hamid;

    2015-01-01

    The susceptibility of the aging brain to neurodegenerative disease may in part be attributed to cellular aging of the microglial cells that survey it. We investigated the effect of cellular aging induced by telomere shortening on microglia by the use of mice lacking the telomerase RNA component...... (TERC) and design-based stereology. TERC knockout (KO) mice had a significantly reduced number of CD11b(+) microglia in the dentate gyrus. Because of an even greater reduction in dentate gyrus volume, microglial density was, however, increased. Microglia in TERC KO mice maintained a homogenous...... distribution and normal expression of CD45 and CD68 and the aging marker, ferritin, but were morphologically distinct from microglia in both adult and old wild-type mice. TERC KO mice also showed increased cellular apoptosis and impaired spatial learning. Our results suggest that individual microglia...

  11. Alcohol Attenuates Activation in the Bilateral Anterior Insula during an Emotional Processing Task: A Pilot Study †

    OpenAIRE

    Padula, Claudia B.; Simmons, Alan N.; Matthews, Scott C; Robinson, Shannon K.; Tapert, Susan F.; Schuckit, Marc A.; Paulus, Martin P.

    2011-01-01

    Aims: Alcohol acutely reduces agitation and is widely used in social situations, but the neural substrates of emotion processing during its intoxication are not well understood. We examine whether alcohol's social stress dampening effect may be via reduced activity in the cortical systems that subserve awareness of bodily sensations, and are associated with affective distress. Methods: Blood oxygen level-dependent activation was measured through 24 functional magnetic resonance imaging sessio...

  12. Inhibition of glycogen synthase kinase 3β activity with lithium prevents and attenuates paclitaxel-induced neuropathic pain.

    Science.gov (United States)

    Gao, M; Yan, X; Weng, H-R

    2013-12-19

    Paclitaxel (taxol) is a first-line chemotherapy-drug used to treat many types of cancers. Neuropathic pain and sensory dysfunction are the major toxicities, which are dose-limiting and significantly reduce the quality of life in patients. Two known critical spinal mechanisms underlying taxol-induced neuropathic pain are an increased production of pro-inflammatory cytokines including interleukin-1β (IL-1β) and suppressed glial glutamate transporter activities. In this study, we uncovered that increased activation of glycogen synthase kinase 3beta (GSK3β) in the spinal dorsal horn was concurrently associated with increased protein expressions of GFAP, IL-1β and a decreased protein expression of glial glutamate transporter 1 (GLT-1), as well as the development and maintenance of taxol-induced neuropathic pain. The enhanced GSK3β activities were supported by the concurrently decreased AKT and mTOR activities. The changes of all these biomarkers were basically prevented when animals received pre-emptive lithium (a GSK3β inhibitor) treatment, which also prevented the development of taxol-induced neuropathic pain. Further, chronic lithium treatment, which began on day 11 after the first taxol injection, reversed the existing mechanical and thermal allodynia induced by taxol. The taxol-induced increased GSK3β activities and decreased AKT and mTOR activities in the spinal dorsal horn were also reversed by lithium. Meanwhile, protein expressions of GLT-1, GFAP and IL-1β in the spinal dorsal horn were improved. Hence, suppression of spinal GSK3β activities is a key mechanism used by lithium to reduce taxol-induced neuropathic pain, and targeting spinal GSK3β is an effective approach to ameliorate GLT-1 expression and suppress the activation of astrocytes and IL-1β over-production in the spinal dorsal horn.

  13. Thermal cooking changes the profile of phenolic compounds, but does not attenuate the anti-inflammatory activities of black rice

    Directory of Open Access Journals (Sweden)

    Sassy Bhawamai

    2016-09-01

    Full Text Available Background: Evidence on biological activities of cooked black rice is limited. This study examined the effects of washing and cooking on the bioactive ingredients and biological activities of black rice. Methods: Cooked rice was prepared by washing 0–3 times followed by cooking in a rice cooker. The acidic methanol extracts of raw and cooked rice were used for the analyses. Results: Raw black rice, both washed and unwashed, had higher contents of polyphenols, anthocyanins, and cyanidin-3-glucoside (C3G, but lower protocatechuic acid (PA, than did cooked samples. Similarly, raw rice extracts were higher in ferric-reducing antioxidant power (FRAP activities than extracts of cooked samples. Nonetheless, extracts of raw and cooked rice showed similar inhibitory potencies on nitric oxide, tumor necrosis factor-α, and interleukin-6 productions in lipopolysaccharide-activated macrophages, whereas equivalent amounts of C3G and PA did not possess such inhibitory effects. Conclusions: Thermal cooking decreased total anthocyanin and C3G contents and the FRAP antioxidative capacity, but did not affect anti-inflammatory activities of black rice. Neither C3G nor PA contributed to the anti-inflammatory activity of black rice.

  14. Thermal cooking changes the profile of phenolic compounds, but does not attenuate the anti-inflammatory activities of black rice

    Science.gov (United States)

    Bhawamai, Sassy; Lin, Shyh-Hsiang; Hou, Yuan-Yu; Chen, Yue-Hwa

    2016-01-01

    Background Evidence on biological activities of cooked black rice is limited. This study examined the effects of washing and cooking on the bioactive ingredients and biological activities of black rice. Methods Cooked rice was prepared by washing 0–3 times followed by cooking in a rice cooker. The acidic methanol extracts of raw and cooked rice were used for the analyses. Results Raw black rice, both washed and unwashed, had higher contents of polyphenols, anthocyanins, and cyanidin-3-glucoside (C3G), but lower protocatechuic acid (PA), than did cooked samples. Similarly, raw rice extracts were higher in ferric-reducing antioxidant power (FRAP) activities than extracts of cooked samples. Nonetheless, extracts of raw and cooked rice showed similar inhibitory potencies on nitric oxide, tumor necrosis factor-α, and interleukin-6 productions in lipopolysaccharide-activated macrophages, whereas equivalent amounts of C3G and PA did not possess such inhibitory effects. Conclusions Thermal cooking decreased total anthocyanin and C3G contents and the FRAP antioxidative capacity, but did not affect anti-inflammatory activities of black rice. Neither C3G nor PA contributed to the anti-inflammatory activity of black rice. PMID:27652685

  15. Korean Red Ginseng Extract Attenuates 3-Nitropropionic Acid-Induced Huntington’s-Like Symptoms

    Directory of Open Access Journals (Sweden)

    Minhee Jang

    2013-01-01

    Full Text Available Korean red ginseng (KRG possesses neuroprotective activity. However, the potential neuroprotective value of KRG for the striatal toxicity is largely unknown. We investigated whether KRG extract (KRGE could have a neuroprotective effect in a 3-nitropropionic acid- (3-NP induced (i.p. Huntington’s disease (HD model. KRGE (50, 100, and 250 mg/kg/day, p.o. was administrated 10 days before 3-NP injection (pre-administration, from the same time with 3-NP injection (co-administration, or from the peak point of neurological impairment by 3-NP injection (post-administration. Pre-administration of KRGE produced the greatest neuroprotective effect in this model. Pre-administration of KRGE significantly decreased 3-NP-induced neurological impairment, lethality, lesion area, and neuronal loss in the 3-NP-injected striatum. KRGE attenuated microglial activation and phosphorylation of mitogen-activated protein kinases (MAPKs and nuclear factor-kappa B (NF-κB signal pathway. KRGE also reduced the level of mRNA expression of tumor necrosis factor-alpha, interleukin- (IL- 1β, IL-6, inducible nitric oxide synthase, and OX-42. Interestingly, the intrathecal administration of SB203580 (a p38 inhibitor or PD98059 (an inhibitor of MAPK Kinase, MEK increased the survival rate in the 3-NP-induced HD model. Pre-administration of KRGE may effectively inhibit 3-NP-induced striatal toxicity via the inhibition of the phosphorylation of MAPKs and NF-κB pathways, indicating its therapeutic potential for suppressing Huntington’s-like symptoms.

  16. The attenuation and the attenuators: strategies and tactics

    Directory of Open Access Journals (Sweden)

    Antonio Briz

    2013-12-01

    Full Text Available This work is inscribed in a research project (ES.POR.ATENUAÇÃO that seeks to analyze and explain the attenuator activity in different regional varieties of Spanish and Portuguese, in order to perform, subsequently, different contrastive intralinguistic and interlinguistic studies. In this article, we explain some of the theoretical and methodological principles on which are based the qualitative and quantitative analysis. And especially, we will refer to the concept of attenuation (Briz 1995, 2002, 2003, 2005, 2007a, 2012.

  17. Antiretroviral medications disrupt microglial phagocytosis of β-amyloid and increase its production by neurons: Implications for HIV-associated neurocognitive disorders

    Directory of Open Access Journals (Sweden)

    Giunta Brian

    2011-06-01

    Full Text Available Abstract Up to 50% of long-term HIV infected patients, including those with systemically well-controlled infection, commonly experience memory problems and slowness, difficulties in concentration, planning, and multitasking. Deposition of Aβ plaques is also a common pathological feature of HIV infection. However, it is not clear whether this accumulation is due to AD-like processes, HIV-associated immunosuppression, Tat protein-induced Aβ elevations, and/or the effects of single highly active antiretroviral therapy (ART. Here we evaluated the effects of several ART medications (Zidovudine, Lamivudine, Indinavir, and Abacavir alone and in combination on: 1 Aβ1-40, 42 generation in murine N2a cells transfected with the human "Swedish" mutant form of APP; 2 microglial phagocytosis of FITC-Aβ1-42 peptides in cultured murine N9 microglia. We report for the first time that these antiretroviral compounds (10 μM generally increase Aβ generation (~50-200% in SweAPP N2a cells and markedly inhibit microglial phagocytosis of FITC-Aβ1-42 peptides in murine microglia. The most significant amyloidogenic effects were observed with combined ART (p in vitro studies, these findings raise the possibility that ART may play a casual role in the elevated Aβ found in the brains of those infected with HIV. Therefore these compounds may consequently contribute to cognitive decline observed in HIV associated neurocognitive disorders (HAND.

  18. The caspase-1 inhibitor AC-YVAD-CMK attenuates acute gastric injury in mice: involvement of silencing NLRP3 inflammasome activities.

    Science.gov (United States)

    Zhang, Fang; Wang, Liang; Wang, Jun-jie; Luo, Peng-fei; Wang, Xing-tong; Xia, Zhao-fan

    2016-04-07

    This study evaluated the protective effects of inhibiting caspase-1 activity or gastric acid secretion on acute gastric injury in mice. AC-YVAD-CMK, omeprazole, or vehicle were administered to mice before cold-restraint stress- or ethanol-induced gastric injury. Survival rates and histological evidence of gastric injury of mice pretreated with AC-YVAD-CMK or omeprazole, and exposed to cold-restraint stress, improved significantly relative to the vehicle group. The increased levels of tumour necrosis factor-α, interleukin (IL)-1β, IL-6, and IL-18 following cold-stress injury were decreased by AC-YVAD-CMK, but not omeprazole, pretreatment. The increased expression of CD68 in gastric tissues was inhibited significantly by AC-YVAD-CMK pretreatment. Inhibiting caspase-1 activity in the NLRP3 inflammasome decreased gastric cell apoptosis, and the expression of Bax and cleaved caspase-3. AC-YVAD-CMK pretreatment significantly inhibited cold-restraint stress-induced increases in the expression of phosphorylated IκB-alpha and P38. General anatomy and histological results showed the protective effect of AC-YVAD-CMK on ethanol-induced acute gastric injury. Overall, our results showed that the caspase-1 inhibitor AC-YVAD-CMK protected against acute gastric injury in mice by affecting the NLRP3 inflammasome and attenuating inflammatory processes and apoptosis. This was similar to the mechanism associated with NF-κB and P38 mitogen-activated protein kinase signalling pathways.

  19. Attenuation of the suppressive activity of cellular splicing factor SRSF3 by Kaposi sarcoma-associated herpesvirus ORF57 protein is required for RNA splicing.

    Science.gov (United States)

    Majerciak, Vladimir; Lu, Mathew; Li, Xiaofan; Zheng, Zhi-Ming

    2014-11-01

    Kaposi sarcoma-associated herpesvirus (KSHV) ORF57 is a multifunctional post-transcriptional regulator essential for viral gene expression during KSHV lytic infection. ORF57 requires interactions with various cellular proteins for its function. Here, we identified serine/arginine-rich splicing factor 3 (SRSF3, formerly known as SRp20) as a cellular cofactor involved in ORF57-mediated splicing of KSHV K8β RNA. In the absence of ORF57, SRSF3 binds to a suboptimal K8β intron and inhibits K8β splicing. Knockdown of SRSF3 promotes K8β splicing, mimicking the effect of ORF57. The N-terminal half of ORF57 binds to the RNA recognition motif of SRSF3, which prevents SRSF3 from associating with the K8β intron RNA and therefore attenuates the suppressive effect of SRSF3 on K8β splicing. ORF57 also promotes splicing of heterologous non-KSHV transcripts that are negatively regulated by SRSF3, indicating that the effect of ORF57 on SRSF3 activity is independent of RNA target. SPEN proteins, previously identified as ORF57-interacting partners, suppress ORF57 splicing activity by displacing ORF57 from SRSF3-RNA complexes. In summary, we have identified modulation of SRSF3 activity as the molecular mechanism by which ORF57 promotes RNA splicing.

  20. Photonic Crystal Fiber Attenuator

    Institute of Scientific and Technical Information of China (English)

    Joo Beom Eom; Hokyung Kim; Jinchae Kim; Un-Chul Paek; Byeong Ha Lee

    2003-01-01

    We propose a novel fiber attenuator based on photonic crystal fibers. The difference in the modal field diameters of a conventional single mode fiber and a photonic crystal fiber was used. A variable optical attenuator was also achieved by applying macro-bending on the PCF part of the proposed attenuator

  1. Platelet-derived growth factor-D modulates extracellular matrix homeostasis and remodeling through TIMP-1 induction and attenuation of MMP-2 and MMP-9 gelatinase activities

    Energy Technology Data Exchange (ETDEWEB)

    Borkham-Kamphorst, Erawan, E-mail: ekamphorst@ukaachen.de; Alexi, Pascal; Tihaa, Lidia; Haas, Ute; Weiskirchen, Ralf, E-mail: rweiskirchen@ukaachen.de

    2015-02-13

    Platelet-derived growth factor-D (PDGF-D) is a more recent recognized growth factor involved in the regulation of several cellular processes, including cell proliferation, transformation, invasion, and angiogenesis by binding to and activating its cognate receptor PDGFR-β. After bile duct ligation or in the carbon tetrachloride-induced hepatic fibrosis model{sub ,} PDGF-D showed upregulation comparable to PDGF-B. Moreover, adenoviral PDGF-D gene transfer induced hepatic stellate cell proliferation and liver fibrosis. We here investigated the molecular mechanism of PDGF-D involvement in liver fibrogenesis. Therefore, the GRX mouse cell line was stimulated with PDGF-D and evaluated for fibrotic markers and PDGF-D signaling pathways in comparison to the other PDGF isoforms. We found that PDGF-D failed to enhance Col I and α-smooth muscle actin (α-SMA) production but has capacity to upregulate expression of the tissue inhibitor of metalloprotease 1 (TIMP-1) resulting in attenuation of MMP-2 and MMP-9 gelatinase activity as indicated by gelatinase zymography. This phenomenon was restored through application of a PDGF-D neutralizing antibody. Unexpectedly, PDGF-D incubation decreased both PDGFR-α and -β in mRNA and protein levels, and PDGF-D phosphorylated typrosines specific for PDGFR-α and -β. We conclude that PDGF-D intensifies fibrogenesis by interfering with the fibrolytic activity of the TIMP-1/MMP system and that PDGF-D signaling is mediated through both PDGF-α and -β receptors. - Highlights: • PDGF-D signals through PDGF receptor type α and β. • PDGF-D modulates extracellular matrix homeostasis and remodeling. • Like PDGF-B, PDGF-D triggers phosphorylation of PLC-γ, Akt/PKB, JNK, ERK1/2, and p38. • PDGF-D induces TIMP-1 expression through ERK and p38 MAPK. • PDGF-D attenuates MMP-2 and MMP-9 gelatinase activities.

  2. Low-Dose Ribavirin Treatments Attenuate Neuroinflammatory Activation of BV-2 Cells by Interfering with Inducible Nitric Oxide Synthase

    Science.gov (United States)

    Bozic, Iva; Savic, Danijela; Jovanovic, Marija; Bjelobaba, Ivana; Laketa, Danijela; Nedeljkovic, Nadezda; Stojiljkovic, Mirjana; Pekovic, Sanja; Lavrnja, Irena

    2015-01-01

    Microglia play a key role in defending central nervous system from various internal and external threats. However, their excessive and/or chronic activation is associated with deleterious effects in a variety of neurodegenerative diseases. Previously, we have shown that ribavirin when applied in clinically relevant dosage (10 μM) modulates activated microglia in complex fashion inducing both anti- and proinflammatory effects, simultaneously causing cytotoxicity. Here, we examined potential of low-dose ribavirin (0.1 and 1 μM) to modulate activated BV-2 microglia. Morphological and functional activation of BV-2 cells was achieved with lipopolysaccharide (LPS) stimulation. Our results demonstrated that low-dose ribavirin did not induce cell death, while 10 μM ribavirin promoted LPS induced apoptosis. We determined that 1 μM ribavirin was equally efficient in deactivation of LPS induced morphological changes as 10 μM ribavirin treatment. Ribavirin showed halfway success in reducing markers of functional activation of microglia. Namely, none of the doses had effect on LPS triggered production of proinflammatory cytokine tumor necrosis factor alpha. On the other hand, low-dose ribavirin proved its effectiveness in reduction of another inflammatory mediator, nitric oxide, by inhibiting inducible form of nitric oxide synthase. Our results imply that low-dose ribavirin may alleviate nitrosative stress during neuroinflammation. PMID:26413464

  3. Low-Dose Ribavirin Treatments Attenuate Neuroinflammatory Activation of BV-2 Cells by Interfering with Inducible Nitric Oxide Synthase

    Directory of Open Access Journals (Sweden)

    Iva Bozic

    2015-01-01

    Full Text Available Microglia play a key role in defending central nervous system from various internal and external threats. However, their excessive and/or chronic activation is associated with deleterious effects in a variety of neurodegenerative diseases. Previously, we have shown that ribavirin when applied in clinically relevant dosage (10 μM modulates activated microglia in complex fashion inducing both anti- and proinflammatory effects, simultaneously causing cytotoxicity. Here, we examined potential of low-dose ribavirin (0.1 and 1 μM to modulate activated BV-2 microglia. Morphological and functional activation of BV-2 cells was achieved with lipopolysaccharide (LPS stimulation. Our results demonstrated that low-dose ribavirin did not induce cell death, while 10 μM ribavirin promoted LPS induced apoptosis. We determined that 1 μM ribavirin was equally efficient in deactivation of LPS induced morphological changes as 10 μM ribavirin treatment. Ribavirin showed halfway success in reducing markers of functional activation of microglia. Namely, none of the doses had effect on LPS triggered production of proinflammatory cytokine tumor necrosis factor alpha. On the other hand, low-dose ribavirin proved its effectiveness in reduction of another inflammatory mediator, nitric oxide, by inhibiting inducible form of nitric oxide synthase. Our results imply that low-dose ribavirin may alleviate nitrosative stress during neuroinflammation.

  4. Light-activation through indirect ceramic restorations: does the overexposure compensate for the attenuation in light intensity during resin cement polymerization?

    Directory of Open Access Journals (Sweden)

    Albano Luis Novaes Bueno

    2011-02-01

    Full Text Available OBJECTIVES: This study evaluated the effects of light exposure through simulated indirect ceramic restorations (SICR on hardness (KHN of dual-cured resin cements (RCs, immediately after light-activation and 24 h later. MATERIAL AND METHODS: Three dual-cured RCs were evaluated: Eco-Link (Ivoclar Vivadent, Rely X ARC (3M ESPE, and Panavia F (Kuraray Medical Inc.. The RCs were manipulated in accordance to the manufacturers' instructions and were placed into cylindrical acrylic matrixes (1-mm-thick and 4-mm diameter. The RC light-activation (Optilux 501; Demetron Kerr was performed through a glass slide for 120 s (control group, or through 2-mm or 4-mm thick SICRs (IPS Empress II; Ivoclar Vivadent. The specimens were submitted to KHN analysis immediately and 24 h after light-activation. The data obtained at the 2 evaluation intervals were submitted to 2-way ANOVA repeated measures and post-hoc Tukey's test (pre-set alpha of 5%. RESULTS: Lower KHN was observed when light-activation was performed through SICRs for Eco-Link at all evaluation intervals and for Rely X ARC 24 h later. For Panavia F, no significant difference in KHN was observed between control and experimental groups, regardless of evaluation interval. Most groups exhibited higher KHN after 24 h than immediately after light-activation, with the exception of Rely X ARC light-activated through SICR, as no significant difference in KHN was found between evaluation intervals. CONCLUSIONS: Light overexposure did not compensate for light intensity attenuation due to the presence of SICR when Rely X and Eco-Link were used. Although hardness of such RCs increased over a 24-h interval, the RCs subjected to light overexposure did not reach the hardness values exhibited after direct light exposure.

  5. MicroRNA-17-mediated down-regulation of apoptotic protease activating factor 1 attenuates apoptosome formation and subsequent apoptosis of cardiomyocytes.

    Science.gov (United States)

    Song, Seungjun; Seo, Hyang-Hee; Lee, Se-Yeon; Lee, Chang Yeon; Lee, Jiyun; Yoo, Kyung-Jong; Yoon, Cheesoon; Choi, Eunhyun; Hwang, Ki-Chul; Lee, Seahyoung

    2015-09-18

    Heart diseases such as myocardial infarction (MI) can damage individual cardiomyocytes, leading to the activation of cell death programs. The most scrutinized type of cell death in the heart is apoptosis, and one of the key events during the propagation of apoptotic signaling is the formation of apoptosomes, which relay apoptotic signals by activating caspase-9. As one of the major components of apoptosomes, apoptotic protease activating factor 1 (Apaf-1) facilitates the formation of apoptosomes containing cytochrome c (Cyto-c) and deoxyadenosine triphosphate (dATP). Thus, it may be possible to suppress the activation of the apoptotic program by down-regulating the expression of Apaf-1 using miRNAs. To validate this hypothesis, we selected a number of candidate miRNAs that were expected to target Apaf-1 based on miRNA target prediction databases. Among these candidate miRNAs, we empirically identified miR-17 as a novel Apaf-1-targeting miRNA. The delivery of exogenous miR-17 suppressed Apaf-1 expression and consequently attenuated formation of the apoptosome complex containing caspase-9, as demonstrated by co-immunoprecipitation and immunocytochemistry. Furthermore, miR-17 suppressed the cleavage of procaspase-9 and the subsequent activation of caspase-3, which is downstream of activated caspase-9. Cell viability tests also indicated that miR-17 pretreatment significantly prevented the norepinephrine-induced apoptosis of cardiomyocytes, suggesting that down-regulation of apoptosome formation may be an effective strategy to prevent cellular apoptosis. These results demonstrate the potential of miR-17 as an effective anti-apoptotic agent. PMID:26265044

  6. Gemfibrozil, a lipid lowering drug, inhibits the activation of primary human microglia via peroxisome proliferator-activated receptor β

    OpenAIRE

    Jana, Malabendu; Pahan, Kalipada

    2012-01-01

    Microglial activation participates in the pathogenesis of various neuroinflammatory and neurodegenerative diseases. However, mechanisms by which microglial activation could be controlled are poorly understood. Peroxisome proliferator-activated receptors (PPAR) are transcription factors belonging to the nuclear receptor super family with diverse effect. This study underlines the importance of PPARβ/δ in mediating the anti-inflammatory effect of gemfibrozil, an FDA-approved lipid-lowering drug,...

  7. Isorhamnetin attenuates atherosclerosis by inhibiting macrophage apoptosis via PI3K/AKT activation and HO-1 induction.

    Directory of Open Access Journals (Sweden)

    Yun Luo

    Full Text Available Isorhamnetin (Iso is a flavonoid compound extracted from the Chinese herb Hippophae rhamnoides L. Previous studies have revealed its anti-cancer, anti-inflammatory, and anti-oxidant activities. This study investigated the ability of Iso to inhibit oxidized low-density lipoprotein (ox-LDL-induced cell apoptosis in THP-1-derived macrophages. The effects of Iso on atherosclerosis in vivo were also evaluated in apolipoprotein E knockout (ApoE-/- mice fed a high fat diet.Iso showed significant inhibitory effects on ox-LDL-induced THP-1-derived macrophage injuries via decreasing reactive oxygen species levels, lipid deposition, and caspase-3 activation, restoring mitochondrial membrane potential, reducing the number of terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL-positive cells, and regulating apoptosis-related proteins. We also determined the protective effects of Iso by PI3K/AKT activation and HO-1 induction. Iso reduced the atherosclerotic plaque size in vivo in ApoE-/- mice as assessed by oil red O, Sudan IV staining, and CD68-positive cells, and reduced macrophage apoptosis as assessed by caspase-3 and TUNEL assays in lesions.In conclusion, our results show that Iso inhibited atherosclerotic plaque development in ApoE-/- mice by PI3K/AKT activation and HO-1 induction.

  8. Curcumin attenuates β-catenin signaling in prostate cancer cells through activation of protein kinase D1.

    Directory of Open Access Journals (Sweden)

    Vasudha Sundram

    Full Text Available Prostate cancer is the most commonly diagnosed cancer affecting 1 in 6 males in the US. Understanding the molecular basis of prostate cancer progression can serve as a tool for early diagnosis and development of novel treatment strategies for this disease. Protein Kinase D1 (PKD1 is a multifunctional kinase that is highly expressed in normal prostate. The decreased expression of PKD1 has been associated with the progression of prostate cancer. Therefore, synthetic or natural products that regulate this signaling pathway can serve as novel therapeutic modalities for prostate cancer prevention and treatment. Curcumin, the active ingredient of turmeric, has shown anti-cancer properties via modulation of a number of different molecular pathways. Herein, we have demonstrated that curcumin activates PKD1, resulting in changes in β-catenin signaling by inhibiting nuclear β-catenin transcription activity and enhancing the levels of membrane β-catenin in prostate cancer cells. Modulation of these cellular events by curcumin correlated with decreased cell proliferation, colony formation and cell motility and enhanced cell-cell aggregation in prostate cancer cells. In addition, we have also revealed that inhibition of cell motility by curcumin is mediated by decreasing the levels of active cofilin, a downstream target of PKD1. The potent anti-cancer effects of curcumin in vitro were also reflected in a prostate cancer xenograft mouse model. The in vivo inhibition of tumor growth also correlated with enhanced membrane localization of β-catenin. Overall, our findings herein have revealed a novel molecular mechanism of curcumin action via the activation of PKD1 in prostate cancer cells.

  9. Palmitate-induced Endoplasmic Reticulum stress and subsequent C/EBPα Homologous Protein activation attenuates leptin and Insulin-like growth factor 1 expression in the brain.

    Science.gov (United States)

    Marwarha, Gurdeep; Claycombe, Kate; Schommer, Jared; Collins, David; Ghribi, Othman

    2016-11-01

    The peptide hormones Insulin-like growth factor-1 (IGF1) and leptin mediate a myriad of biological effects - both in the peripheral and central nervous systems. The transcription of these two hormones is regulated by the transcription factor C/EBPα, which in turn is negatively regulated by the transcription factor C/EBP Homologous Protein (CHOP), a specific marker of endoplasmic reticulum (ER) stress. In the peripheral system, disturbances in leptin and IGF-1 levels are implicated in a variety of metabolic diseases including obesity, diabetes, atherosclerosis and cardiovascular diseases. Current research suggests a positive correlation between consumption of diets rich in saturated free fatty acids (sFFA) and metabolic diseases. Induction of ER stress and subsequent dysregulation in the expression levels of leptin and IGF-1 have been shown to mediate sFFA-induced metabolic diseases in the peripheral system. Palmitic acid (palmitate), the most commonly consumed sFFA, has been shown to be up-taken by the brain, where it may promote neurodegeneration. However, the extent to which palmitate induces ER stress in the brain and attenuates leptin and IGF1 expression has not been determined. We fed C57BL/6J mice a palmitate-enriched diet and determined effects on the expression levels of leptin and IGF1 in the hippocampus and cortex. We further determined the extent to which ER stress and subsequent CHOP activation mediate the palmitate effects on the transcription of leptin and IGF1. We demonstrate that palmitate induces ER stress and decreases leptin and IGF1 expression by inducing the expression of CHOP. The molecular chaperone 4-phenylbutyric acid (4-PBA), an inhibitor of ER stress, precludes the palmitate-evoked down-regulation of leptin and IGF1 expression. Furthermore, the activation of CHOP in response to ER stress is pivotal in the attenuation of leptin and IGF1 expression as knocking-down CHOP in mice or in SH-SY5Y and Neuro-2a (N2a) cells rescues the palmitate

  10. A hepatoprotective Lindera obtusiloba extract suppresses growth and attenuates insulin like growth factor-1 receptor signaling and NF-kappaB activity in human liver cancer cell lines

    Directory of Open Access Journals (Sweden)

    Stroh Thorsten

    2011-05-01

    Full Text Available Abstract Background In traditional Chinese and Korean medicine, an aqueous extract derived from wood and bark of the Japanese spice bush Lindera obtusiloba (L.obtusiloba is applied to treat inflammations and chronic liver diseases including hepatocellular carcinoma. We previously demonstrated anti-fibrotic effects of L.obtusiloba extract in hepatic stellate cells. Thus, we here consequently examine anti-neoplastic effects of L.obtusiloba extract on human hepatocellular carcinoma (HCC cell lines and the signaling pathways involved. Methods Four human HCC cell lines representing diverse stages of differentiation were treated with L.obtusiloba extract, standardized according to its known suppressive effects on proliferation and TGF-β-expression. Beside measurement of proliferation, invasion and apoptosis, effects on signal transduction and NF-κB-activity were determined. Results L.obtusiloba extract inhibited proliferation and induced apoptosis in all HCC cell lines and provoked a reduced basal and IGF-1-induced activation of the IGF-1R signaling cascade and a reduced transcriptional NF-κB-activity, particularly in the poorly differentiated SK-Hep1 cells. Pointing to anti-angiogenic effects, L.obtusiloba extract attenuated the basal and IGF-1-induced expression of hypoxia inducible factor-1α, vascular endothelial growth factor, peroxisome proliferator-activated receptor-γ, cyclooxygenase-2 and inducible nitric oxide synthase. Conclusions The traditional application of the extract is confirmed by our experimental data. Due to its potential to inhibit critical receptor tyrosine kinases involved in HCC progression via the IGF-1 signaling pathway and NF-κB, the standardized L.obtusiloba extract should be further analysed for its active compounds and explored as (complementary treatment option for HCC.

  11. Recombinant human brain natriuretic peptide attenuates LPS-induced cellular injury in human fetal lung fibroblasts via inhibiting MAPK and NF-κB pathway activation.

    Science.gov (United States)

    Song, Zhi; Zhao, Xiu; Liu, Martin; Jin, Hongxu; Cui, Yan; Hou, Mingxiao; Gao, Yan

    2016-08-01

    Inflammatory responses are vital in lung injury diseases, particularly acute respiratory distress syndrome (ARDS). Recombinant human brain natriuretic peptide (rhBNP) has been shown to exhibit anti‑inflammatory effects in vivo in our previous studies. The present study aimed to investigate the mechanisms underlying the anti‑inflammatory effects of rhBNP on lipopolysaccharide (LPS)-induced human fetal lung fibroblasts (HFL-1). The results showed that LPS induced a significant increase in the leakage of lactate dehydrogenase and the secretion of interleukin (IL)‑1β. Activation of p38, extracellular-signal regulated kinase (ERK) 1/2, c‑Jun NH2-terminal kinase (JNK) mitogen‑activated protein kinases (MAPK)s, and nuclear factor (NF)‑κB in HFL‑1 cells was also observed following treatment with LPS. Treatment with rhBNP (0.1 µM) reduced the production of IL‑1β at the protein and mRNA levels. Moreover, rhBNP decreased the phosphorylation of p38, ERK1/2 and JNK induced by LPS. However, the JNK inhibitor, SP600125, significantly inhibited LPS‑induced IL‑1β production. These results indicate that the inhibition of IL‑1β by may dependent upon the JNK signaling pathway. The LPS‑induced NF‑κB activation was also suppressed by rhBNP, and IL‑1β production was inhibited by the NF‑κB inhibitor. Furthermore, NF‑κB activation was attenuated by the JNK inhibitor, indicating that NF‑κB activation was dependent on the JNK signaling pathway. The present study suggests that rhBNP exhibits an anti‑inflammatory effect on LPS‑induced HFL‑1 cell injury via the inhibition of MAPK and NF‑κB signaling pathways and may exhibit therapeutic potential for acute lung injury and ARDS. PMID:27314600

  12. Activation of angiotensin-converting enzyme 2 (ACE2) attenuates allergic airway inflammation in rat asthma model.

    Science.gov (United States)

    Dhawale, Vaibhav Shrirang; Amara, Venkateswara Rao; Karpe, Pinakin Arun; Malek, Vajir; Patel, Deep; Tikoo, Kulbhushan

    2016-09-01

    Angiotensin-I converting enzyme (ACE) is positively correlated to asthma, chronic obstructive pulmonary disease (COPD), acute respiratory distress syndrome (ARDS) and is highly expressed in lungs. ACE2, the counteracting enzyme of ACE, was proven to be protective in pulmonary, cardiovascular diseases. In the present study we checked the effect of ACE2 activation in animal model of asthma. Asthma was induced in male wistar rats by sensitization and challenge with ovalbumin and then treated with ACE2 activator, diminazene aceturate (DIZE) for 2weeks. 48h after last allergen challenge, animals were anesthetized, blood, BALF, femoral bone marrow lavage were collected for leucocyte count; trachea for measuring airway responsiveness to carbachol; lungs and heart were isolated for histological studies and western blotting. In our animal model, the characteristic features of asthma such as altered airway responsiveness to carbachol, eosinophilia and neutrophilia were observed. Western blotting revealed the increased pulmonary expression of ACE1, IL-1β, IL-4, NF-κB, BCL2, p-AKT, p-p38 and decreased expression of ACE2 and IκB. DIZE treatment prevented these alterations. Intraalveolar interstitial thickening, inflammatory cell infiltration, interstitial fibrosis, oxidative stress and right ventricular hypertrophy in asthma control animals were also reversed by DIZE treatment. Activation of ACE2 by DIZE conferred protection against asthma as evident from biochemical, functional, histological and molecular parameters. To the best of our knowledge, we report for the first time that activation of ACE2 by DIZE prevents asthma progression by altering AKT, p38, NF-κB and other inflammatory markers. PMID:27343405

  13. Final Report Real Time Monitoring of Rates of Subsurface Microbial Activity Associated with Natural Attenuation and Electron Donor Availability

    Energy Technology Data Exchange (ETDEWEB)

    Lovley, Derek R. [Univ. of Massachusetts, Amherst, MA (United States)

    2016-03-22

    The project was successful in developing new sensing technologies for monitoring rates of microbial activity in soils and sediments and also developed a novel proof-of-concept for monitoring the presence of bioavailable concentrations of a diversity of metabolites and toxic components in sedimentary environments. These studies led not only to publications in the peer-reviewed literature, but also two patent applications and a start-up company.

  14. Seizure-like activity in a juvenile Angelman syndrome mouse model is attenuated by reducing Arc expression.

    Science.gov (United States)

    Mandel-Brehm, Caleigh; Salogiannis, John; Dhamne, Sameer C; Rotenberg, Alexander; Greenberg, Michael E

    2015-04-21

    Angelman syndrome (AS) is a neurodevelopmental disorder arising from loss-of-function mutations in the maternally inherited copy of the UBE3A gene, and is characterized by an absence of speech, excessive laughter, cognitive delay, motor deficits, and seizures. Despite the fact that the symptoms of AS occur in early childhood, behavioral characterization of AS mouse models has focused primarily on adult phenotypes. In this report we describe juvenile behaviors in AS mice that are strain-independent and clinically relevant. We find that young AS mice, compared with their wild-type littermates, produce an increased number of ultrasonic vocalizations. In addition, young AS mice have defects in motor coordination, as well as abnormal brain activity that results in an enhanced seizure-like response to an audiogenic challenge. The enhanced seizure-like activity, but not the increased ultrasonic vocalizations or motor deficits, is rescued in juvenile AS mice by genetically reducing the expression level of the activity-regulated cytoskeleton-associated protein, Arc. These findings suggest that therapeutic interventions that reduce the level of Arc expression have the potential to reverse the seizures associated with AS. In addition, the identification of aberrant behaviors in young AS mice may provide clues regarding the neural circuit defects that occur in AS and ultimately allow new approaches for treating this disorder. PMID:25848016

  15. MaJAZ1 Attenuates the MaLBD5-Mediated Transcriptional Activation of Jasmonate Biosynthesis Gene MaAOC2 in Regulating Cold Tolerance of Banana Fruit.

    Science.gov (United States)

    Ba, Liang-jie; Kuang, Jian-fei; Chen, Jian-ye; Lu, Wang-jin

    2016-02-01

    Previous studies indicated that methyl jasmonate (MeJA) treatment could effectively reduce the chilling injury of many fruits, including banana, but the underlying mechanism is poorly understood. In this study, one lateral organ boundaries (LOB) domain (LBD) gene, designated as MaLBD5, was isolated and characterized from banana fruit. Expression analysis revealed that accumulation of MaLBD5 was induced by cold temperature and MeJA treatment. Subcellular localization and transactivation assays showed that MaLBD5 was localized to the nucleus and possessed transcriptional activation activity. Protein-protein interaction analysis demonstrated that MaLBD5 physically interacted with MaJAZ1, a potential repressor of jasmonate signaling. Furthermore, transient expression assays indicated that MaLBD5 transactivated a jasmonate biosynthesis gene, termed MaAOC2, which was also induced by cold and MeJA. More interestingly, MaJAZ1 attenuated the MaLBD5-mediated transactivation of MaAOC2. These results suggest that MaLBD5 and MaJAZ1 might act antagonistically in relation to MeJA-induced cold tolerance of banana fruit, at least partially via affecting jasmonate biosynthesis. Collectively, our findings expand the knowledge of the transcriptional regulatory network of MeJA-mediated cold tolerance of banana fruit.

  16. Inhibition of HSP90 Promotes Neural Stem Cell Survival from Oxidative Stress through Attenuating NF-κB/p65 Activation

    Science.gov (United States)

    Jiang, Wenkai; Zhou, Lin

    2016-01-01

    Stem cell survival after transplantation determines the efficiency of stem cell treatment, which develops as a novel potential therapy for several central nervous system (CNS) diseases in recent decades. The engrafted stem cells face the damage of oxidative stress, inflammation, and immune response at the lesion point in host. Among the damaging pathologies, oxidative stress directs stem cells to apoptosis and even death through several signalling pathways and DNA damage. However, the in-detail mechanism of stem cell survival from oxidative stress has not been revealed clearly. Here, in this study, we used hydrogen peroxide (H2O2) to induce the oxidative damage on neural stem cells (NSCs). The damage was in consequence demonstrated involving the activation of heat shock protein 90 (HSP90) and NF-κB/p65 signalling pathways. Further application of the pharmacological inhibitors, respectively, targeting at each signalling indicated an upper-stream role of HSP90 upon NF-κB/p65 on NSCs survival. Preinhibition of HSP90 with the specific inhibitor displayed a significant protection on NSCs against oxidative stress. In conclusion, inhibition of HSP90 would attenuate NF-κB/p65 activation by oxidative induction and promote NSCs survival from oxidative damage. The HSP90/NF-κB mechanism provides a new evidence on rescuing NSCs from oxidative stress and also promotes the stem cell application on CNS pathologies.

  17. Oral Administration of p-Hydroxycinnamic Acid Attenuates Atopic Dermatitis by Downregulating Th1 and Th2 Cytokine Production and Keratinocyte Activation.

    Directory of Open Access Journals (Sweden)

    Hyun-Su Lee

    Full Text Available Atopic dermatitis (AD is a complex disease that is caused by various factors, including environmental change, genetic defects, and immune imbalance. We previously showed that p-hydroxycinnamic acid (HCA isolated from the roots of Curcuma longa inhibits T-cell activation without inducing cell death. Here, we demonstrated that oral administration of HCA in a mouse model of ear AD attenuates the following local and systemic AD manifestations: ear thickening, immune-cell infiltration, production of AD-promoting immunoregulatory cytokines in ear tissues, increased spleen and draining lymph node size and weight, increased pro-inflammatory cytokine production by draining lymph nodes, and elevated serum immunoglobulin production. HCA treatment of CD4+ T cells in vitro suppressed their proliferation and differentiation into Th1 or Th2 and their Th1 and Th2 cytokine production. HCA treatment of keratinocytes lowered their production of the pro-inflammatory cytokines that drive either Th1 or Th2 responses in AD. Thus, HCA may be of therapeutic potential for AD as it acts by suppressing keratinocyte activation and downregulating T-cell differentiation and cytokine production.

  18. Oral Administration of p-Hydroxycinnamic Acid Attenuates Atopic Dermatitis by Downregulating Th1 and Th2 Cytokine Production and Keratinocyte Activation.

    Science.gov (United States)

    Lee, Hyun-Su; Choi, Eun-Ju; Lee, Kyung-Sik; Kim, Hye-Ran; Na, Bo-Ra; Kwon, Min-Sung; Jeong, Gil-Saeng; Choi, Hyun Gyu; Choi, Eun Young; Jun, Chang-Duk

    2016-01-01

    Atopic dermatitis (AD) is a complex disease that is caused by various factors, including environmental change, genetic defects, and immune imbalance. We previously showed that p-hydroxycinnamic acid (HCA) isolated from the roots of Curcuma longa inhibits T-cell activation without inducing cell death. Here, we demonstrated that oral administration of HCA in a mouse model of ear AD attenuates the following local and systemic AD manifestations: ear thickening, immune-cell infiltration, production of AD-promoting immunoregulatory cytokines in ear tissues, increased spleen and draining lymph node size and weight, increased pro-inflammatory cytokine production by draining lymph nodes, and elevated serum immunoglobulin production. HCA treatment of CD4+ T cells in vitro suppressed their proliferation and differentiation into Th1 or Th2 and their Th1 and Th2 cytokine production. HCA treatment of keratinocytes lowered their production of the pro-inflammatory cytokines that drive either Th1 or Th2 responses in AD. Thus, HCA may be of therapeutic potential for AD as it acts by suppressing keratinocyte activation and downregulating T-cell differentiation and cytokine production. PMID:26959360

  19. SIRT1 activation by pterostilbene attenuates the skeletal muscle oxidative stress injury and mitochondrial dysfunction induced by ischemia reperfusion injury.

    Science.gov (United States)

    Cheng, Yedong; Di, Shouyin; Fan, Chongxi; Cai, Liping; Gao, Chao; Jiang, Peng; Hu, Wei; Ma, Zhiqiang; Jiang, Shuai; Dong, Yushu; Li, Tian; Wu, Guiling; Lv, Jianjun; Yang, Yang

    2016-08-01

    Ischemia reperfusion (IR) injury is harmful to skeletal muscles and causes mitochondrial oxidative stress. Pterostilbene (PTE), an analogue of resveratrol, has organic protective effects against oxidative stress. However, no studies have investigated whether PTE can protect against IR-related skeletal muscular injury. In this study, we sought to evaluate the protective effect of PTE against IR-related skeletal muscle injury and to determine the mechanisms in this process. Male Sprague-Dawley rats were pretreated with PTE for a week and then underwent limb IR surgery. The IR injury induced segmental necrosis and apoptosis, myofilament disintegration, thicker interstitial spaces, and inflammatory cell infiltration. Furthermore, mitochondrial respiratory chain activity in the muscular tissue was inhibited, methane dicarboxylic aldehyde concentration and myeloperoxidase activity were up-regulated, and superoxide dismutase was down-regulated after IR. However, these effects were significantly inhibited by PTE in a dose-dependent manner. The mechanism underlying IR injury is attributed to the down-regulation of silent information regulator 1 (SIRT1)-FOXO1/p53 pathway and the increase of the Bax/Bcl2 ratio, Cleaved poly ADP-ribose polymerase 1, Cleaved Caspase 3, which can be reversed with PTE. Furthermore, EX527, an SIRT1 inhibitor, counteracted the protective effects of PTE on IR-related muscle injury. In conclusion, PTE has protective properties against IR injury of the skeletal muscles. The mechanism of this protective effect depends on the activation of the SIRT1-FOXO1/p53 signaling pathway and the decrease of the apoptotic ratio in skeletal muscle cells. PMID:27270300

  20. Inhibition of cerebrovascular raf activation attenuates cerebral blood flow and prevents upregulation of contractile receptors after subarachnoid hemorrhage

    Directory of Open Access Journals (Sweden)

    Maddahi Aida

    2011-10-01

    Full Text Available Abstract Background Late cerebral ischemia carries high morbidity and mortality after subarachnoid hemorrhage (SAH due to reduced cerebral blood flow (CBF and the subsequent cerebral ischemia which is associated with upregulation of contractile receptors in the vascular smooth muscle cells (SMC via activation of mitogen-activated protein kinase (MAPK of the extracellular signal-regulated kinase (ERK1/2 signal pathway. We hypothesize that SAH initiates cerebrovascular ERK1/2 activation, resulting in receptor upregulation. The raf inhibitor will inhibit the molecular events upstream ERK1/2 and may provide a therapeutic window for treatment of cerebral ischemia after SAH. Results Here we demonstrate that SAH increases the phosphorylation level of ERK1/2 in cerebral vessels and reduces the neurology score in rats in additional with the CBF measured by an autoradiographic method. The intracisternal administration of SB-386023-b, a specific inhibitor of raf, given 6 h after SAH, aborts the receptor changes and protects the brain from the development of late cerebral ischemia at 48 h. This is accompanied by reduced phosphorylation of ERK1/2 in cerebrovascular SMC. SAH per se enhances contractile responses to endothelin-1 (ET-1, 5-carboxamidotryptamine (5-CT and angiotensin II (Ang II, upregulates ETB, 5-HT1B and AT1 receptor mRNA and protein levels. Treatment with SB-386023-b given as late as at 6 h but not at 12 h after the SAH significantly decreased the receptor upregulation, the reduction in CBF and the neurology score. Conclusion These results provide evidence for a role of the ERK1/2 pathway in regulation of expression of cerebrovascular SMC receptors. It is suggested that raf inhibition may reduce late cerebral ischemia after SAH and provides a realistic time window for therapy.

  1. Zinc oxide and titanium dioxide nanoparticles induce oxidative stress, inhibit growth, and attenuate biofilm formation activity of Streptococcus mitis.

    Science.gov (United States)

    Khan, Shams Tabrez; Ahmad, Javed; Ahamed, Maqusood; Musarrat, Javed; Al-Khedhairy, Abdulaziz A

    2016-06-01

    Streptococcus mitis from the oral cavity causes endocarditis and other systemic infections. Rising resistance against traditional antibiotics amongst oral bacteria further aggravates the problem. Therefore, antimicrobial and antibiofilm activities of zinc oxide and titanium dioxide nanoparticles (NPs) synthesized and characterized during this study against S. mitis ATCC 6249 and Ora-20 were evaluated in search of alternative antimicrobial agents. ZnO and TiO2-NPs exhibited an average size of 35 and 13 nm, respectively. The IC50 values of ZnO and TiO2-NPs against S. mitis ATCC 6249 were 37 and 77 µg ml(-1), respectively, while the IC50 values against S. mitis Ora-20 isolate were 31 and 53 µg ml(-1), respectively. Live and dead staining, biofilm formation on the surface of polystyrene plates, and extracellular polysaccharide production show the same pattern. Exposure to these nanoparticles also shows an increase (26-83 %) in super oxide dismutase (SOD) activity. Three genes, namely bapA1, sodA, and gtfB like genes from these bacteria were identified and sequenced for quantitative real-time PCR analysis. An increase in sodA gene (1.4- to 2.4-folds) levels and a decrease in gtfB gene (0.5- to 0.9-folds) levels in both bacteria following exposure to ZnO and TiO2-NPs were observed. Results presented in this study verify that ZnO-NPs and TiO2-NPs can control the growth and biofilm formation activities of these strains at very low concentration and hence can be used as alternative antimicrobial agents for oral hygiene. PMID:26837748

  2. Microglial cell dysregulation in brain aging and neurodegeneration

    OpenAIRE

    von Bernhardi, Rommy; Eugenín-von Bernhardi, Laura; Eugenín, Jaime

    2015-01-01

    Aging is the main risk factor for neurodegenerative diseases. In aging, microglia undergoes phenotypic changes compatible with their activation. Glial activation can lead to neuroinflammation, which is increasingly accepted as part of the pathogenesis of neurodegenerative diseases, including Alzheimer’s disease (AD). We hypothesize that in aging, aberrant microglia activation leads to a deleterious environment and neurodegeneration. In aged mice, microglia exhibit an increased expression of c...

  3. Transcriptional activation of APAF1 by KAISO (ZBTB33) and p53 is attenuated by RelA/p65.

    Science.gov (United States)

    Koh, Dong-In; An, Haemin; Kim, Min-Young; Jeon, Bu-Nam; Choi, Seo-Hyun; Hur, Sujin Susanne; Hur, Man-Wook

    2015-09-01

    KAISO, a member of the POK protein family, is induced by DNA-damaging agents to enhance apoptosis in a p53-dependent manner. Previously, we found that p53 interacts with KAISO, and acetylation of p53 lysine residues by p300 is modulated by KAISO. APAF1, the core molecule of the apoptosome, is transcriptionally activated by KAISO only in cells expressing p53, which binds to APAF1 promoter p53-response elements (p53REs). APAF1 transcriptional upregulation is further enhanced by KAISO augmentation of p53 binding to the APAF1 promoter distal p53RE#1 (bp, -765 to -739). Interestingly, a NF-κB response element, located close to the p53RE#1, mediates APAF1 transcriptional repression by affecting interaction between KAISO and p53. Ectopic RelA/p65 expression led to depletion of nuclear KAISO, with KAISO being mainly detected in the cytoplasm. RelA/p65 cytoplasmic sequestration of KAISO prevents its nuclear interaction with p53, decreasing APAF1 transcriptional activation by a p53