Radix Scrophulariae extracts (harpagoside) suppresses hypoxia-induced microglial activation and neurotoxicity

BMC Complementary and Alternative Medicine

Cherng-Jyh Ke³  Ching-Yun Chen⁴  Man-Hai Liu¹  Jui-Sheng Sun³  Yi-Wen Hong²  Shiow-Yunn Sheu² 

[1]Department of Food Science, College Health Science and Technology, China University of Science and Technology, Taipei, Taiwan

[2]School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei, Taiwan

[3]Biomimetic Systems Research Center, National Chiao Tung University, Hsin-Chu, Taiwan

[4]Institute of Biomedical Engineering, College of Engineering and College of Medicine, National Taiwan University, Taipei, Taiwan

关键词: Anti-inflammation;    Activation;    Microglial cells;    Hypoxia;    Harpagoside;   

Others  :  1224873
DOI  :  10.1186/s12906-015-0842-x

 received in 2015-01-27, accepted in 2015-09-01,  发布年份 2015

【 摘 要 】

Background

Hypoxia could lead to microglia activation and inflammatory mediators’ overproduction. These inflammatory molecules could amplify the neuroinflammatory process and exacerbate neuronal injury. The aim of this study is to find out whether harpagoside could reduce hypoxia-induced microglia activation.

Methods

In this study, primary microglia cells harvested from neonatal ICR mice were activated by exposure to hypoxia (1 % O ₂for 3 h). Harpagoside had been shown to be no cytotoxicity on microglia cells by MTT assay. The scavenger effect of harpagoside on hypoxia-enhanced microglial cells proliferation, associated inflammatory genes expression (COX-II, IL-1β and IL-6 genes) and NO synthesis were also examined.

Results

Hypoxia enhances active proliferation of microglial cells, while harpagoside can scavenge this effect. We find that harpagoside could scavenge hypoxia-enhanced inflammatory genes expression (COX-2, IL-1β and IL-6 genes) and NO synthesis of microglial cells. Under 3 h’ hypoxic stimulation, the nuclear contents of p65 and hypoxia inducible factor-1α (HIF-1α) significantly increase, while the cytosol IκB-α content decreases; these effects can be reversed by 1 h’s pre-incubation of 10 ⁻⁸  M harpagoside. Harpagoside could decrease IκB-α protein phosphorylation and inhibit p65 protein translocation from the cytosol to the nucleus, thus suppress NF-κB activation and reduce the HIF-1α generation.

Conclusion

These results suggested that the anti-inflammatory mechanism of harpagoside might be associated with the NF-κB signaling pathway. Harpagoside protect against hypoxia-induced toxicity on microglial cells through HIF-α pathway.

【 授权许可】

   
2015 Sheu et al.

【 图 表 】

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【 参考文献 】

• [1]Li Y, Chen G, Zhao J, Nie X, Wan C, Liu J et al.. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) induces microglial nitric oxide production and subsequent rat primary cortical neuron apoptosis through p38/JNK MAPK pathway. Toxicology. 2013; 312:132-41.
• [2]Yang J, Wang C, Nie X, Shi S, Xiao J, Ma X et al.. Perfluorooctane sulfonate mediates microglial activation and secretion of TNF-αthrough Ca2+−dependent PKC-NF-кB signaling. Int Immunopharmacol. 2015; 28(1):52-60.
• [3]Garden GA, Möller T. Microglia biology in health and disease. J Neuroimmune Pharmacol. 2006; 1(2):127-37.
• [4]Kaindl AM, Degos V, Peineau S, Gouadon E, Chhor V, Loron G et al.. Activation of microglial N-methyl-D-aspartate receptors triggers inflammation and neuronal cell death in the developing and mature brain. Ann Neurol. 2012; 72(4):536-49.
• [5]Rubio-Perez JM, Morillas-Ruiz JM. A review: inflammatory process in Alzheimer’s disease, role of cytokines. Sci World J. 2012; 2012:756357.
• [6]Peng L, Li M, Xu YZ, Zhang GY, Yang C, Zhou YN et al.. Effect of Si-Miao-Yong-An on the stability of atherosclerotic plaque in a diet-induced rabbit model. J Ethnopharmacol. 2012; 143(1):241-8.
• [7]Huang TH, Tran VH, Duke RK, Tan S, Chrubasik S, Roufogalis BD et al.. Harpagoside suppresses lipopolysaccharide-induced iNOS and COX-2 expression through inhibition of NF-kappa B activation. J Ethnopharmacol. 2006; 104(1–2):149-55.
• [8]Kaszkin M, Beck KF, Koch E, Erdelmeier C, Kusch S, Pfeilschifter J et al.. Downregulation of iNOS expression in rat mesangial cells by special extracts of Harpagophytum procumbens derives from harpagoside-dependent and independent effects. Phytomedicine. 2004; 11(7–8):585-95.
• [9]Saura J, Tusell JM, Serratosa J. High-yield isolation of murine microglia by mild trypsinization. Glia. 2003; 44(3):183-9.
• [10]Green LC, Wagner DA, Glogowski J, Skipper PL, Wishnok JS, Tannenbaum SR. Analysis of nitrate, nitrite, and [15N]nitrate in biological fluids. Anal Biochem. 1982; 126(1):131-8.
• [11]Vittori D, Pregi N, Pérez G, Garbossa G, Nesse A. The distinct erythropoietin functions that promote cell survival and proliferation are affected by aluminum exposure through mechanisms involving erythropoietin receptor. Biochim Biophys Acta. 2005; 1743(1–2):29-36.
• [12]Kaur C, Rathnasamy G, Ling EA. Roles of activated microglia in hypoxia induced neuroinflammation in the developing brain and the retina. J Neuroimmune Pharmacol. 2013; 8(1):66-78.
• [13]Agostinho P, Cunha RA, Oliveira C. Neuroinflammation, oxidative stress and the pathogenesis of Alzheimer’s disease. Curr Pharm Des. 2010; 16(25):2766-78.
• [14]Perry RT, Collins JS, Wiener H, Acton R, Go RC. The role of TNF and its receptors in Alzheimer’s disease. Neurobiol Aging. 2001; 22(6):873-83.
• [15]Kuno R, Wang J, Kawanokuchi J, Takeuchi H, Mizuno T, Suzumura A. Autocrine activation of microglia by tumor necrosis factor-alpha. J Neuroimmunol. 2005; 162(1–2):89-96.
• [16]Yermakova A, O’Banion MK. Cyclooxygenases in the central nervous system: implications for treatment of neurological disorders. Curr Pharm Des. 2000; 6(17):1755-76.
• [17]Háznagy-Radnai E, Balogh Á, Czigle S, Máthé I, Hohmann J, Blazsó G. Antiinflammatory activities of Hungarian Stachys species and their iridoids. Phytother Res. 2012; 26(4):505-9.
• [18]Winter CD, Iannotti F, Pringle AK, Trikkas C, Clough GF, Church MK. A microdialysis method for the recovery of IL-1beta, IL-6 and nerve growth factor from human brain in vivo. J Neurosci Methods. 2002; 119(1):45-50.
• [19]Rossi F, Bianchini E. Synergistic induction of nitric oxide by beta-amyloid and cytokines in astrocytes. Biochem Biophys Res Commun. 1996; 225(2):474-8.
• [20]Mrak RE, Griffin WS. Interleukin-1, neuroinflammation, and Alzheimer’s disease. Neurobiol Aging. 2001; 22(6):903-8.
• [21]Raivich G, Bohatschek M, Kloss CU, Werner A, Jones LL, Kreutzberg GW. Neuroglial activation repertoire in the injured brain: graded response, molecular mechanisms and cues to physiological function. Brain Res Brain Res Rev. 1999; 30(1):77-105.
• [22]Benveniste EN. Cytokine actions in the central nervous system. Cytokine Growth Factor Rev. 1998; 9(3–4):259-75.
• [23]Heyser CJ, Masliah E, Samimi A, Campbell IL, Gold LH. Progressive decline in avoidance learning paralleled by inflammatory neurodegeneration in transgenic mice expressing interleukin 6 in the brain. Proc Natl Acad Sci U S A. 1997; 94(4):1500-5.
• [24]Heneka MT, Wiesinger H, Dumitrescu-Ozimek L, Riederer P, Feinstein DL, Klockgether T. Neuronal and glial coexpression of argininosuccinate synthetase and inducible nitric oxide synthase in Alzheimer disease. J Neuropathol Exp Neurol. 2001; 60(9):906-16.
• [25]Smith MA, Richey Harris PL, Sayre LM, Beckman JS, Perry G. Widespread peroxynitrite-mediated damage in Alzheimer’s disease. J Neurosci. 1997; 17(8):2653-7.
• [26]Boje KM, Arora PK. Microglial-produced nitric oxide and reactive nitrogen oxides mediate neuronal cell death. Brain Res. 1992; 587(2):250-6.
• [27]Heneka MT, Löschmann PA, Gleichmann M, Weller M, Schulz JB, Wüllner U et al.. Induction of nitric oxide synthase and nitric oxide-mediated apoptosis in neuronal PC12 cells after stimulation with tumor necrosis factor-alpha/lipopolysaccharide. J Neurochem. 1998; 71(1):88-94.
• [28]Guix FX, Uribesalgo I, Coma M, Muñoz FJ. The physiology and pathophysiology of nitric oxide in the brain. Prog Neurobiol. 2005; 76(2):126-52.
• [29]Eltzschig HK, Carmeliet P. Hypoxia and inflammation. N Engl J Med. 2011; 364(7):656-65.
• [30]Lu DY, Liou HC, Tang CH, Fu WM. Hypoxia-induced iNOS expression in microglia is regulated by the PI3-kinase/Akt/mTOR signaling pathway and activation of hypoxia inducible factor-1alpha. Biochem Pharmacol. 2006; 72(8):992-1000.
• [31]Kim JS, Jobin C. The flavonoid luteolin prevents lipopolysaccharide-induced NF-kappaB signalling and gene expression by blocking IkappaB kinase activity in intestinal epithelial cells and bone-marrow derived dendritic cells. Immunology. 2005; 115(3):375-87.
• [32]Vogiatzoglou A, Mulligan AA, Lentjes MA, Luben RN, Spencer JP, Schroeter H et al.. Flavonoid intake in European adults (18 to 64 years). PLoS One. 2015; 10(5): Article ID e0128132
• [33]Zheng LT, Ock J, Kwon BM, Suk K. Suppressive effects of flavonoid fisetin on lipopolysaccharide-induced microglial activation and neurotoxicity. Int Immunopharmacol. 2008; 8(3):484-94.
• [34]Rinwa P, Kumar A. Quercetin suppress microglial neuroinflammatory response and induce antidepressent-like effect in olfactory bulbectomized rats. Neuroscience. 2013; 255:86-98.
• [35]Johnson RW. Feeding the beast: can microglia in the senescent brain be regulated by diet? Brain Behav Immun. 2015; 43:1-8.
• [36]Engelhart MJ, Geerlings MI, Ruitenberg A, van Swieten JC, Hofman A, Witteman JC et al.. Dietary intake of antioxidants and risk of Alzheimer disease. JAMA. 2002; 287(24):3223-9.
• [37]Freeman RS, Barone MC. Targeting hypoxia-inducible factor (HIF) as a therapeutic strategy for CNS disorders. Curr Drug Targets CNS Neurol Disord. 2005; 4(1):85-92.