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A Novel Pyrazolo[3,4-d]pyrimidine Induces Heme Oxygenase-1 and Exerts Anti-Inflammatory and Neuroprotective Effects

  • Lee, Ji Ae (Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine) ;
  • Kwon, Young-Won (Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine) ;
  • Kim, Hye Ri (Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine) ;
  • Shin, Nari (Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine) ;
  • Son, Hyo Jin (Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine) ;
  • Cheong, Chan Seong (Center for Neuro-Medicine, Brain Science Institute, Korea Institute of Science and Technology) ;
  • Kim, Dong Jin (Center for Neuro-Medicine, Brain Science Institute, Korea Institute of Science and Technology) ;
  • Hwang, Onyou (Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine)
  • Received : 2021.03.26
  • Accepted : 2021.10.15
  • Published : 2022.03.31

Abstract

The anti-oxidant enzyme heme oxygenase-1 (HO-1) is known to exert anti-inflammatory effects. From a library of pyrazolo[3,4-d]pyrimidines, we identified a novel compound KKC080096 that upregulated HO-1 at the mRNA and protein levels in microglial BV-2 cells. KKC080096 exhibited anti-inflammatory effects via suppressing nitric oxide, interleukin1β (IL-1β), and iNOS production in lipopolysaccharide (LPS)-challenged cells. It inhibited the phosphorylation of IKK and MAP kinases (p38, JNK, ERK), which trigger inflammatory signaling, and whose activities are inhibited by HO-1. Further, KKC080096 upregulated anti-inflammatory marker (Arg1, YM1, CD206, IL-10, transforming growth factor-β [TGF-β]) expression. In 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridinetreated mice, KKC080096 lowered microglial activation, protected the nigral dopaminergic neurons, and nigral damage-associated motor deficits. Next, we elucidated the mechanisms by which KKC080096 upregulated HO-1. KKC080096 induced the phosphorylation of AMPK and its known upstream kinases LKB1 and CaMKKbeta, and pharmacological inhibition of AMPK activity reduced the effects of KKC080096 on HO-1 expression and LPS-induced NO generation, suggesting that KKC080096-induced HO-1 upregulation involves LKB1/AMPK and CaMKKbeta/AMPK pathway activation. Further, KKC080096 caused an increase in cellular Nrf2 level, bound to Keap1 (Nrf2 inhibitor protein) with high affinity, and blocked Keap1-Nrf2 interaction. This Nrf2 activation resulted in concurrent induction of HO-1 and other Nrf2-targeted antioxidant enzymes in BV-2 and in dopaminergic CATH.a cells. These results indicate that KKC080096 is a potential therapeutic for oxidative stress-and inflammation-related neurodegenerative disorders such as Parkinson's disease.

Keywords

Acknowledgement

This research was funded by the National Research Foundation of Korea (2009-0081674,5 & 2018R1A6A3A01010564), Republic of Korea.

References

  1. Alam, J., Stewart, D., Touchard, C., Boinapally, S., Choi, A.M., and Cook, J.L. (1999). Nrf2, a Cap'n'Collar transcription factor, regulates induction of the heme oxygenase-1 gene. J. Biol. Chem. 274, 26071-26078. https://doi.org/10.1074/jbc.274.37.26071
  2. Al-Rashed, F., Calay, D., Lang, M., Thornton, C.C., Bauer, A., Kiprianos, A., Haskard, D.O., Seneviratne, A., Boyle, J.J., Schonthal, A.H., et al. (2018). Celecoxib exerts protective effects in the vascular endothelium via COX-2-independent activation of AMPK-CREB-Nrf2 signalling. Sci. Rep. 8, 6271. https://doi.org/10.1038/s41598-018-24548-z
  3. Arthur, J.S. and Ley, S.C. (2013). Mitogen-activated protein kinases in innate immunity. Nat. Rev. Immunol. 13, 679-692. https://doi.org/10.1038/nri3495
  4. Baier, S.R., Zbasnik, R., Schlegel, V., and Zempleni, J. (2014). Off-target effects of sulforaphane include the derepression of long terminal repeats through histone acetylation events. J. Nutr. Biochem. 25, 665-668. https://doi.org/10.1016/j.jnutbio.2014.02.007
  5. Blasi, E., Barluzzi, R., Bocchini, V., Mazzolla, R., and Bistoni, F. (1990). Immortalization of murine microglial cells by a v-raf/v-myc carrying retrovirus. J. Neuroimmunol. 27, 229-237. https://doi.org/10.1016/0165-5728(90)90073-V
  6. Carroll, K.C., Viollet, B., and Suttles, J. (2013). AMPKα1 deficiency amplifies proinflammatory myeloid APC activity and CD40 signaling. J. Leukoc. Biol. 94, 1113-1121. https://doi.org/10.1189/jlb.0313157
  7. Chang, K.H. and Chen, C.M. (2020). The role of oxidative stress in Parkinson's disease. Antioxidants (Basel) 9, 597. https://doi.org/10.3390/antiox9070597
  8. Chauhan, M. and Kumar, R. (2013). Medicinal attributes of pyrazolo[3,4-d] pyrimidines: a review. Bioorg. Med. Chem. 21, 5657-5668. https://doi.org/10.1016/j.bmc.2013.07.027
  9. Cheung, K.L., Khor, T.O., and Kong, A.N. (2009). Synergistic effect of combination of phenethyl isothiocyanate and sulforaphane or curcumin and sulforaphane in the inhibition of inflammation. Pharm. Res. 26, 224-231. https://doi.org/10.1007/s11095-008-9734-9
  10. de Zeeuw, D., Akizawa, T., Audhya, P., Bakris, G.L., Chin, M., Christ-Schmidt, H., Goldsberry, A., Houser, M., Krauth, M., Lambers Heerspink, H.J., et al. (2013). Bardoxolone methyl in type 2 diabetes and stage 4 chronic kidney disease. N. Engl. J. Med. 369, 2492-2503. https://doi.org/10.1056/NEJMoa1306033
  11. Ewart, M.A., Kohlhaas, C.F., and Salt, I.P. (2008). Inhibition of tumor necrosis factor α-stimulated monocyte adhesion to human aortic endothelial cells by AMP-activated protein kinase. Arterioscler. Thromb. Vasc. Biol. 28, 2255-2257. https://doi.org/10.1161/ATVBAHA.108.175919
  12. Franklin, K.B.J. and Paxinos, G. (1997). The Mouse Brain in Stereotaxic Coordinates (San Diego: Academic Press).
  13. Galic, S., Fullerton, M.D., Schertzer, J.D., Sikkema, S., Marcinko, K., Walkley, C.R., Izon, D., Honeyman, J., Chen, Z.P., van Denderen, B.J., et al. (2011). Hematopoietic AMPKβ1 reduces mouse adipose tissue macrophage inflammation and insulin resistance in obesity. J. Clin. Invest. 121, 4903-4915. https://doi.org/10.1172/JCI58577
  14. Giri, S., Nath, N., Smith, B., Viollet, B., Singh, A.K., and Singh, I. (2004). 5-aminoimidazole-4-carboxamide-1-β-4-ribofuranoside inhibits proinflammatory response in glial cells: a possible role of AMP-activated protein kinase. J. Neurosci. 24, 479-487. https://doi.org/10.1523/jneurosci.4288-03.2004
  15. Hattori, Y., Suzuki, K., Hattori, S., and Kasai, K. (2006). Metformin inhibits cytokine-induced nuclear factor kappaB activation via AMP-activated protein kinase activation in vascular endothelial cells. Hypertension 47, 1183-1188. https://doi.org/10.1161/01.hyp.0000221429.94591.72
  16. Hawley, S.A., Pan, D.A., Mustard, K.J., Ross, L., Bain, J., Edelman, A.M., Frenguelli, B.G., and Hardie, D.G. (2005). Calmodulin-dependent protein kinase kinase-β is an alternative upstream kinase for AMP-activated protein kinase. Cell Metab. 2, 9-19. https://doi.org/10.1016/j.cmet.2005.05.009
  17. Huang, N.L., Chiang, S.H., Hsueh, C.H., Liang, Y.J., Chen, Y.J., and Lai, L.P. (2009). Metformin inhibits TNF-α-induced IκB kinase phosphorylation, IκB-α degradation and IL-6 production in endothelial cells through PI3Kdependent AMPK phosphorylation. Int. J. Cardiol. 134, 169-175. https://doi.org/10.1016/j.ijcard.2008.04.010
  18. Ji, J., Xue, T.F., Guo, X.D., Yang, J., Guo, R.B., Wang, J., Huang, J.Y., Zhao, X.J., and Sun, X.L. (2018). Antagonizing peroxisome proliferator-activated receptor gamma facilitates M1-to-M2 shift of microglia by enhancing autophagy via the LKB1-AMPK signaling pathway. Aging Cell 17, e12774. https://doi.org/10.1111/acel.12774
  19. Joo, M.S., Kim, W.D., Lee, K.Y., Kim, J.H., Koo, J.H., and Kim, S.G. (2016). AMPK facilitates nuclear accumulation of Nrf2 by phosphorylating at serine 550. Mol. Cell. Biol. 36, 1931-1942. https://doi.org/10.1128/MCB.00118-16
  20. Kanno, Y., Ishisaki, A., Kawashita, E., Kuretake, H., Ikeda, K., and Matsuo, O. (2016). uPA attenuated LPS-induced inflammatory osteoclastogenesis through the plasmin/PAR-1/Ca2+/CaMKK/AMPK axis. Int. J. Biol. Sci. 12, 63-71. https://doi.org/10.7150/ijbs.12690
  21. Kawai, T. and Akira, S. (2007). Signaling to NF-κB by Toll-like receptors. Trends Mol. Med. 13, 460-469. https://doi.org/10.1016/j.molmed.2007.09.002
  22. Kim, S., Indu Viswanath, A.N., Park, J.H., Lee, H.E., Park, A.Y., Choi, J.W., Kim, H.J., Londhe, A.M., Jang, B.K., Lee, J., et al. (2020). Nrf2 activator via interference of Nrf2-Keap1 interaction has antioxidant and anti-inflammatory properties in Parkinson's disease animal model. Neuropharmacology 167, 107989. https://doi.org/10.1016/j.neuropharm.2020.107989
  23. Kim, S.T., Son, H.J., Choi, J.H., Ji, I.J., and Hwang, O. (2010). Vertical grid test and modified horizontal grid test are sensitive methods for evaluating motor dysfunctions in the MPTP mouse model of Parkinson's disease. Brain Res. 1306, 176-183. https://doi.org/10.1016/j.brainres.2009.09.103
  24. Kurkowska-Jastrzebska, I., Wronska, A., Kohutnicka, M., Czlonkowski, A., and Czlonkowska, A. (1999). The inflammatory reaction following 1-methyl-4-phenyl-1,2,3, 6-tetrahydropyridine intoxication in mouse. Exp. Neurol. 156, 50-61. https://doi.org/10.1006/exnr.1998.6993
  25. Lee, E., Eo, J.C., Lee, C., and Yu, J.W. (2021). Distinct features of brain-resident macrophages: microglia and non-parenchymal brain macrophages. Mol. Cells 44, 281-291. https://doi.org/10.14348/molcells.2021.0060
  26. Lee, J.A., Kim, D.J., and Hwang, O. (2019). KMS99220 exerts anti-inflammatory effects, activates the Nrf2 signaling and interferes with IKK, JNK and p38 MAPK via HO-1. Mol. Cells 42, 702-710. https://doi.org/10.14348/molcells.2019.0129
  27. Lee, J.A., Kim, H.R., Kim, J., Park, K.D., Kim, D.J., and Hwang, O. (2018). The novel neuroprotective compound KMS99220 has an early anti-neuroinflammatory effect via AMPK and HO-1, independent of Nrf2. Exp. Neurobiol. 27, 408-418. https://doi.org/10.5607/en.2018.27.5.408
  28. Lee, J.A., Kim, H.R., Son, H.J., Shin, N., Han, S.H., Cheong, C.S., Kim, D.J., and Hwang, O. (2020). A novel pyrazolo [3,4-d] pyrimidine, KKC080106, activates the Nrf2 pathway and protects nigral dopaminergic neurons. Exp. Neurol. 332, 113387. https://doi.org/10.1016/j.expneurol.2020.113387
  29. Lee, J.A., Kim, J.H., Woo, S.Y., Son, H.J., Han, S.H., Jang, B.K., Choi, J.W., Kim, D.J., Park, K.D., and Hwang, O. (2015b). A novel compound VSC2 has anti-inflammatory and antioxidant properties in microglia and in Parkinson's disease animal model. Br. J. Pharmacol. 172, 1087-1100. https://doi.org/10.1111/bph.12973
  30. Lee, J.A., Son, H.J., Kim, J.H., Park, K.D., Shin, N., Kim, H.R., Kim, E.M., Kim, D.J., and Hwang, O. (2016). A novel synthetic isothiocyanate ITC-57 displays antioxidant, anti-inflammatory, and neuroprotective properties in a mouse Parkinson's disease model. Free Radic. Res. 50, 1188-1199. https://doi.org/10.1080/10715762.2016.1223293
  31. Lee, J.A., Son, H.J., Park, K.D., Han, S.H., Shin, N., Kim, J.H., Kim, H.R., Kim, D.J., and Hwang, O. (2015a). A novel compound ITC-3 activates the Nrf2 signaling and provides neuroprotection in Parkinson's disease models. Neurotox. Res. 28, 332-345. https://doi.org/10.1007/s12640-015-9550-z
  32. Li, C., Zhang, C., Zhou, H., Feng, Y., Tang, F., Hoi, M.P.M., He, C., Ma, D., Zhao, C., and Lee, S.M.Y. (2018). Inhibitory effects of betulinic acid on LPS-induced neuroinflammation involve M2 microglial polarization via CaMKKβ-dependent AMPK activation. Front. Mol. Neurosci. 11, 98. https://doi.org/10.3389/fnmol.2018.00098
  33. Li, W., Khor, T.O., Xu, C., Shen, G., Jeong, W.S., Yu, S., and Kong, A.N. (2008). Activation of Nrf2-antioxidant signaling attenuates NFκB-inflammatory response and elicits apoptosis. Biochem. Pharmacol. 76, 1485-1489. https://doi.org/10.1016/j.bcp.2008.07.017
  34. Lin, W., Wu, R.T., Wu, T., Khor, T.O., Wang, H., and Kong, A.N. (2008). Sulforaphane suppressed LPS-induced inflammation in mouse peritoneal macrophages through Nrf2 dependent pathway. Biochem. Pharmacol. 76, 967-973. https://doi.org/10.1016/j.bcp.2008.07.036
  35. Liu, W., Bai, F., Wang, H., Liang, Y., Du, X., Liu, C., Cai, D., Peng, J., Zhong, G., Liang, X., et al. (2019). Tim-4 inhibits NLRP3 inflammasome via the LKB1/AMPKαvz pathway in macrophages. J. Immunol. 203, 990-1000. https://doi.org/10.4049/jimmunol.1900117
  36. Liu, Z., Zhang, W., Zhang, M., Zhu, H., Moriasi, C., and Zou, M.H. (2015). Liver kinase B1 suppresses lipopolysaccharide-induced nuclear factor κB (NF-κB) activation in macrophages. J. Biol. Chem. 290, 2312-2320. https://doi.org/10.1074/jbc.M114.616441
  37. Matzinger, M., Fischhuber, K., Poloske, D., Mechtler, K., and Heiss, E.H. (2020). AMPK leads to phosphorylation of the transcription factor Nrf2, tuning transactivation of selected target genes. Redox Biol. 29, 101393. https://doi.org/10.1016/j.redox.2019.101393
  38. Mo, C., Wang, L., Zhang, J., Numazawa, S., Tang, H., Tang, X., Han, X., Li, J., Yang, M., Wang, Z., et al. (2014). The crosstalk between Nrf2 and AMPK signal pathways is important for the anti-inflammatory effect of berberine in LPS-stimulated macrophages and endotoxin-shocked mice. Antioxid. Redox Signal. 20, 574-588. https://doi.org/10.1089/ars.2012.5116
  39. Morse, D., Pischke, S.E., Zhou, Z., Davis, R.J., Flavell, R.A., Loop, T., Otterbein, S.L., Otterbein, L.E., and Choi, A.M. (2003). Suppression of inflammatory cytokine production by carbon monoxide involves the JNK pathway and AP-1. J. Biol. Chem. 278, 36993-36998. https://doi.org/10.1074/jbc.M302942200
  40. Naito, Y., Takagi, T., and Higashimura, Y. (2014). Heme oxygenase-1 and anti-inflammatory M2 macrophages. Arch. Biochem. Biophys. 564, 83-88. https://doi.org/10.1016/j.abb.2014.09.005
  41. Ogawa, N., Hirose, Y., Ohara, S., Ono, T., and Watanabe, Y. (1985). A simple quantitative bradykinesia test in MPTP-treated mice. Res. Commun. Chem. Pathol. Pharmacol. 50, 435-441.
  42. Ogborne, R.M., Rushworth, S.A., Charalambos, C.A., and O'Connell, M.A. (2004). Haem oxygenase-1: a target for dietary antioxidants. Biochem. Soc. Trans. 32, 1003-1005. https://doi.org/10.1042/BST0321003
  43. Poss, K.D. and Tonegawa, S. (1997). Heme oxygenase 1 is required for mammalian iron reutilization. Proc. Natl. Acad. Sci. U. S. A. 94, 10919-10924. https://doi.org/10.1073/pnas.94.20.10919
  44. Rojo, A.I., McBean, G., Cindric, M., Egea, J., Lopez, M.G., Rada, P., Zarkovic, N., and Cuadrado, A. (2014). Redox control of microglial function: molecular mechanisms and functional significance. Antioxid. Redox Signal. 21, 1766-1801. https://doi.org/10.1089/ars.2013.5745
  45. Sag, D., Carling, D., Stout, R.D., and Suttles, J. (2008). Adenosine 5'-monophosphate-activated protein kinase promotes macrophage polarization to an anti-inflammatory functional phenotype. J. Immunol. 181, 8633-8641. https://doi.org/10.4049/jimmunol.181.12.8633
  46. Salminen, A., Hyttinen, J.M., and Kaarniranta, K. (2011). AMP-activated protein kinase inhibits NF-κB signaling and inflammation: impact on healthspan and lifespan. J. Mol. Med. (Berl.) 89, 667-676. https://doi.org/10.1007/s00109-011-0748-0
  47. Satoh, T. and Lipton, S. (2017). Recent advances in understanding NRF2 as a druggable target: development of pro-electrophilic and non-covalent NRF2 activators to overcome systemic side effects of electrophilic drugs like dimethyl fumarate. F1000Res. 6, 2138. https://doi.org/10.12688/f1000research.12111.1
  48. Schindelin, J., Arganda-Carreras, I., Frise, E., Kaynig, V., Longair, M., Pietzsch, T., Preibisch, S., Rueden, C., Saalfeld, S., Schmid, B., et al. (2012). Fiji: an open-source platform for biological-image analysis. Nat. Methods 9, 676-682. https://doi.org/10.1038/nmeth.2019
  49. Schmoll, D., Engel, C.K., and Glombik, H. (2017). The Keap1-Nrf2 protein-protein interaction: a suitable target for small molecules. Drug Discov. Today Technol. 24, 11-17. https://doi.org/10.1016/j.ddtec.2017.10.001
  50. Shaw, R.J., Kosmatka, M., Bardeesy, N., Hurley, R.L., Witters, L.A., DePinho, R.A., and Cantley, L.C. (2004). The tumor suppressor LKB1 kinase directly activates AMP-activated kinase and regulates apoptosis in response to energy stress. Proc. Natl. Acad. Sci. U. S. A. 101, 3329-3335. https://doi.org/10.1073/pnas.0308061100
  51. Sierra, A., Gottfried-Blackmore, A.C., McEwen, B.S., and Bulloch, K. (2007). Microglia derived from aging mice exhibit an altered inflammatory profile. Glia 55, 412-424. https://doi.org/10.1002/glia.20468
  52. Sierra-Filardi, E., Vega, M.A., Sanchez-Mateos, P., Corbi, A.L., and Puig-Kroger, A. (2010). Heme oxygenase-1 expression in M-CSF-polarized M2 macrophages contributes to LPS-induced IL-10 release. Immunobiology 215, 788-795. https://doi.org/10.1016/j.imbio.2010.05.020
  53. Silva, G., Cunha, A., Gregoire, I.P., Seldon, M.P., and Soares, M.P. (2006). The antiapoptotic effect of heme oxygenase-1 in endothelial cells involves the degradation of p38 α MAPK isoform. J. Immunol. 177, 1894-1903. https://doi.org/10.4049/jimmunol.177.3.1894
  54. Son, H.J., Lee, J.A., Shin, N., Choi, J.H., Seo, J.W., Chi, D.Y., Lee, C.S., Kim, E.M., Choe, H., and Hwang, O. (2012). A novel compound PTIQ protects the nigral dopaminergic neurones in an animal model of Parkinson's disease induced by MPTP. Br. J. Pharmacol. 165, 2213-2227. https://doi.org/10.1111/j.1476-5381.2011.01692.x
  55. Son, Y., Chung, H.T., and Pae, H.O. (2014). Differential effects of resveratrol and its natural analogs, piceatannol and 3,5,4'-trans-trimethoxystilbene, on anti-inflammatory heme oxigenase-1 expression in RAW264.7 macrophages. Biofactors 40, 138-145. https://doi.org/10.1002/biof.1108
  56. Suri, C., Fung, B.P., Tischler, A.S., and Chikaraishi, D.M. (1993). Catecholaminergic cell lines from the brain and adrenal glands of tyrosine hydroxylase-SV40 T antigen transgenic mice. J. Neurosci. 13, 1280-1291. https://doi.org/10.1523/jneurosci.13-03-01280.1993
  57. Thornton, C.C., Al-Rashed, F., Calay, D., Birdsey, G.M., Bauer, A., Mylroie, H., Morley, B.J., Randi, A.M., Haskard, D.O., Boyle, J.J., et al. (2016). Methotrexate-mediated activation of an AMPK-CREB-dependent pathway: a novel mechanism for vascular protection in chronic systemic inflammation. Ann. Rheum. Dis. 75, 439-448. https://doi.org/10.1136/annrheumdis-2014-206305
  58. Tu, T.H., Joe, Y., Choi, H.S., Chung, H.T., and Yu, R. (2014). Induction of heme oxygenase-1 with hemin reduces obesity-induced adipose tissue inflammation via adipose macrophage phenotype switching. Mediators Inflamm. 2014, 290708.
  59. Wakabayashi, N., Dinkova-Kostova, A.T., Holtzclaw, W.D., Kang, M.I., Kobayashi, A., Yamamoto, M., Kensler, T.W., and Talalay, P. (2004). Protection against electrophile and oxidant stress by induction of the phase 2 response: fate of cysteines of the Keap1 sensor modified by inducers. Proc. Natl. Acad. Sci. U. S. A. 101, 2040-2045. https://doi.org/10.1073/pnas.0307301101
  60. Wiesel, P., Patel, A.P., DiFonzo, N., Marria, P.B., Sim, C.U., Pellacani, A., Maemura, K., LeBlanc, B.W., Marino, K., Doerschuk, C.M., et al. (2000). Endotoxin-induced mortality is related to increased oxidative stress and end-organ dysfunction, not refractory hypotension, in heme oxygenase1-deficient mice. Circulation 102, 3015-3022. https://doi.org/10.1161/01.CIR.102.24.3015
  61. Woo, S.Y., Kim, J.H., Moon, M.K., Han, S.H., Yeon, S.K., Choi, J.W., Jang, B.K., Song, H.J., Kang, Y.G., Kim, J.W., et al. (2014). Discovery of vinyl sulfones as a novel class of neuroprotective agents toward Parkinson's disease therapy. J. Med. Chem. 57, 1473-1487. https://doi.org/10.1021/jm401788m
  62. Woods, A., Dickerson, K., Heath, R., Hong, S.P., Momcilovic, M., Johnstone, S.R., Carlson, M., and Carling, D. (2005). Ca2+/calmodulin-dependent protein kinase kinase-β acts upstream of AMP-activated protein kinase in mammalian cells. Cell Metab. 2, 21-33. https://doi.org/10.1016/j.cmet.2005.06.005
  63. Woods, A., Johnstone, S.R., Dickerson, K., Leiper, F.C., Fryer, L.G., Neumann, D., Schlattner, U., Wallimann, T., Carlson, M., and Carling, D. (2003). LKB1 is the upstream kinase in the AMP-activated protein kinase cascade. Curr. Biol. 13, 2004-2008. https://doi.org/10.1016/j.cub.2003.10.031
  64. Xu, Y., Xu, Y., Wang, Y., Wang, Y., He, L., Jiang, Z., Huang, Z., Liao, H., Li, J., Saavedra, J.M., et al. (2015). Telmisartan prevention of LPS-induced microglia activation involves M2 microglia polarization via CaMKKβ-dependent AMPK activation. Brain Behav. Immun. 50, 298-313. https://doi.org/10.1016/j.bbi.2015.07.015
  65. Zhao, Y., Li, J., Gu, H., Wei, D., Xu, Y.C., Fu, W., and Yu, Z. (2015a). Conformational preferences of π-π stacking between ligand and protein, analysis derived from crystal structure data geometric preference of π-π interaction. Interdiscip. Sci. 7, 211-220. https://doi.org/10.1007/s12539-015-0263-z
  66. Zhao, Y.F., Zhang, Q., Xi, J.Y., Li, Y.H., Ma, C.G., and Xiao, B.G. (2015b). Multitarget intervention of Fasudil in the neuroprotection of dopaminergic neurons in MPTP-mouse model of Parkinson's disease. J. Neurol. Sci. 353, 28-37. https://doi.org/10.1016/j.jns.2015.03.022
  67. Zhou, X., Cao, Y., Ao, G., Hu, L., Liu, H., Wu, J., Wang, X., Jin, M., Zheng, S., Zhen, X., et al. (2014). CaMKKβ-dependent activation of AMP-activated protein kinase is critical to suppressive effects of hydrogen sulfide on neuroinflammation. Antioxid. Redox Signal. 21, 1741-1758. https://doi.org/10.1089/ars.2013.5587
  68. Zimmermann, K., Baldinger, J., Mayerhofer, B., Atanasov, A.G., Dirsch, V.M., and Heiss, E.H. (2015). Activated AMPK boosts the Nrf2/HO-1 signaling axis-a role for the unfolded protein response. Free Radic. Biol. Med. 88(Pt B), 417-426. https://doi.org/10.1016/j.freeradbiomed.2015.03.030