{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T09:49:18Z","timestamp":1773308958155,"version":"3.50.1"},"reference-count":43,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2015,9,15]],"date-time":"2015-09-15T00:00:00Z","timestamp":1442275200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Gardenamide A (GA) protects the rat retinal ganglion (RGC-5) cells against cell apoptosis induced by H2O2. The protective effect of GA was completely abrogated by the specific phosphoinositide 3-kinase (PI3K) inhibitor LY294002, and the specific protein kinase B (Akt) inhibitor Akt VIII respectively, indicating that the protective mechanism of GA is mediated by the PI3K\/Akt signaling pathway. The specific extracellular signal-regulated kinase (ERK1\/2) inhibitor PD98059 could not block the neuroprotection of GA. GA attenuated the levels of reactive oxygen species (ROS) and malondialdehyde (MDA) induced by H2O2. Western blotting showed that GA promoted the phosphorylation of ERK1\/2, Akt and endothelial nitric oxide synthase (eNOS), respectively, and effectively reversed the H2O2-inhibited phosphorylation of these three proteins. LY294002 completely inhibited the GA-activated phosphorylation of Akt, while only partially inhibiting eNOS. This evidence implies that eNOS may be activated directly by GA. PD98059 attenuated only partially the GA-induced phosphorylation of ERK1\/2 with\/without the presence of H2O2, indicating that GA may activate ERK1\/2 directly. All these results put together confirm that GA protects RGC-5 cells from H2O2 insults via the activation of PI3K\/Akt\/eNOS signaling pathway. Whether the ERK1\/2 signaling pathway is involved requires further investigations.<\/jats:p>","DOI":"10.3390\/ijms160922350","type":"journal-article","created":{"date-parts":[[2015,9,16]],"date-time":"2015-09-16T10:33:36Z","timestamp":1442399616000},"page":"22350-22367","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["Gardenamide A Protects RGC-5 Cells from H2O2-Induced Oxidative Stress Insults by Activating PI3K\/Akt\/eNOS  Signaling Pathway"],"prefix":"10.3390","volume":"16","author":[{"given":"Rikang","family":"Wang","sequence":"first","affiliation":[{"name":"National Pharmaceutical Engineering Center for Solid Preparation in Chinese Herbal Medicine, Jiangxi University of Traditional Chinese Medicine, Nanchang 330006, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lizhi","family":"Peng","sequence":"additional","affiliation":[{"name":"Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy,  Jinan University, Guangzhou 510632, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiaqiang","family":"Zhao","sequence":"additional","affiliation":[{"name":"Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy,  Jinan University, Guangzhou 510632, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Laitao","family":"Zhang","sequence":"additional","affiliation":[{"name":"Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy,  Jinan University, Guangzhou 510632, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cuiping","family":"Guo","sequence":"additional","affiliation":[{"name":"Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy,  Jinan University, Guangzhou 510632, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wenhua","family":"Zheng","sequence":"additional","affiliation":[{"name":"Faculty of Health Sciences, University of Macao, Macao, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Heru","family":"Chen","sequence":"additional","affiliation":[{"name":"Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy,  Jinan University, Guangzhou 510632, China"},{"name":"Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and  New Drugs Research, Guangzhou 510632, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2015,9,15]]},"reference":[{"key":"ref_1","first-page":"19","article-title":"Oxidative stress and neurodegenerative disease","volume":"9","year":"2004","journal-title":"Neurosciences"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1241","DOI":"10.1016\/j.freeradbiomed.2009.02.006","article-title":"Epigenetics, oxidative stress, and Alzheimer disease","volume":"46","author":"Zawia","year":"2009","journal-title":"Free Radic. Biol. Med."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"115","DOI":"10.1016\/S0039-6257(00)00140-5","article-title":"The role of oxidative stress in the pathogenesis of age-related macular degeneration","volume":"45","author":"Beatty","year":"2000","journal-title":"Surv. Ophthalmol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"205","DOI":"10.1016\/S1350-9462(99)00009-9","article-title":"Oxidative damage and protection of the RPE","volume":"19","author":"Cai","year":"2000","journal-title":"Prog. Retin. Eye Res."},{"key":"ref_5","first-page":"743","article-title":"The role of oxidative stress and antioxidants in the pathogenesis of age-related macular degeneration","volume":"66","author":"Yildirim","year":"2011","journal-title":"Clinics"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"86","DOI":"10.1016\/j.neuint.2014.08.009","article-title":"L-Carnitine attenuates H2O2-induced neuron apoptosis via inhibition of endoplasmic reticulum stress","volume":"78","author":"Ye","year":"2014","journal-title":"Neurochem. Int."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1165","DOI":"10.1007\/s10571-014-0091-4","article-title":"Protective Effects of Phillyrin on H2O2-induced Oxidative Stress and Apoptosis in PC12 Cells","volume":"34","author":"Wei","year":"2014","journal-title":"Cell. Mol. Neurobiol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1634","DOI":"10.1111\/j.1471-4159.2006.03907.x","article-title":"Oxidative stress and neurodegeneration: Where are we now?","volume":"97","author":"Halliwell","year":"2006","journal-title":"J. Neurochem."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1763","DOI":"10.1089\/ars.2009.3074","article-title":"Cellular stress responses, the hormesis paradigm, and vitagenes: Novel targets for therapeutic intervention in neurodegenerative disorders","volume":"11","author":"Calabrese","year":"2010","journal-title":"Antioxid. Redox Signal."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"888","DOI":"10.3109\/10715762.2011.574290","article-title":"Antioxidant protection: A promising therapeutic intervention in neurodegenerative disease","volume":"8","author":"Ghosh","year":"2011","journal-title":"Free Radic. Res."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"746","DOI":"10.1248\/cpb.48.746","article-title":"Studies of the constituents of Gardenia species. II. Terpenoids from Gardeniae Fructus","volume":"48","author":"Machida","year":"2000","journal-title":"Chem. Pharm. Bull."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1661","DOI":"10.1002\/cmdc.201200258","article-title":"Synthesis of stable genipin derivatives and studies of their neuroprotective activity in PC12 cells","volume":"7","author":"Luo","year":"2012","journal-title":"ChemMedChem"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"225","DOI":"10.1124\/mol.62.2.225","article-title":"Insulin-like growth factor-1-induced phosphorylation of transcription factor FKHRL1 is mediated by phosphatidylinositol 3-kinase\/Akt kinase and role of this pathway in insulin-like growth factor-1-induced survival of cultured hippocampal neurons","volume":"62","author":"Zheng","year":"2002","journal-title":"Mol. Pharmacol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"231","DOI":"10.1016\/S0092-8674(00)80405-5","article-title":"Akt phosphorylation of BAD couples survival signals to the cell-intrinsic death machinery","volume":"91","author":"Datta","year":"1997","journal-title":"Cell"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"845","DOI":"10.1016\/S0960-9822(99)80371-6","article-title":"The Akt kinase signals directly to endothelial nitric oxide synthase","volume":"9","author":"Michell","year":"1999","journal-title":"Curr. Biol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1016\/j.brainres.2012.06.032","article-title":"The possible role of the Akt signaling pathway in schizophrenia","volume":"1470","author":"Zheng","year":"2012","journal-title":"Brain Res."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"391","DOI":"10.1016\/j.cellsig.2005.05.009","article-title":"High glucose-induced apoptosis in human vascular endothelial cells is mediated through NF-\u03baB and c-Jun NH2-terminal kinase pathway and prevented by PI3K\/Akt\/eNOS pathway","volume":"18","author":"Ho","year":"2006","journal-title":"Cell Signal."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1227","DOI":"10.1194\/jlr.M500507-JLR200","article-title":"Oxidized low density lipoprotein impairs endothelial progenitor cells by regulation of endothelial nitric oxide synthase","volume":"47","author":"Ma","year":"2006","journal-title":"J. Lipid Res."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"5712","DOI":"10.1167\/iovs.13-12085","article-title":"A forensic path to RGC-5 cell line identification: Lessons learned","volume":"54","author":"Krishnamoorthy","year":"2013","journal-title":"Investig. Ophthalmol. Vis. Sci."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1497","DOI":"10.1161\/01.CIR.0000012529.00367.0F","article-title":"Nitric oxide mediates the antiapoptotic effect of insulin in myocardial ischemia-reperfusion: The roles of PI3-kinase, Akt, and endothelial nitric oxide synthase phosphorylation","volume":"105","author":"Gao","year":"2002","journal-title":"Circulation"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"255","DOI":"10.1016\/j.ejphar.2007.12.001","article-title":"Cyclic GMP-dependent neurite outgrowth by genipin and nerve growth factor in PC12h cells","volume":"581","author":"Yamazaki","year":"2008","journal-title":"Eur. J. Pharmacol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1049","DOI":"10.1046\/j.0022-3042.2002.00783.x","article-title":"FKHRL1 and its homologs are new targets of nerve growth factor Trk receptor signaling","volume":"80","author":"Zheng","year":"2002","journal-title":"J. Neurochem."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"e71578","DOI":"10.1371\/journal.pone.0071578","article-title":"Carboxypeptidase E\/NF\u03b11: A new neurotrophic factor against oxidative stress-induced apoptotic cell death mediated by ERK and PI3-K\/AKT pathways","volume":"8","author":"Cheng","year":"2013","journal-title":"PLoS ONE"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"84","DOI":"10.1016\/j.brainres.2004.01.037","article-title":"Inhibition of glycogen synthase kinase 3 beta is involved in the resistance to oxidative stress in neuronal HT22 cells","volume":"1005","author":"Schafer","year":"2004","journal-title":"Brain Res."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"e74826","DOI":"10.1371\/journal.pone.0074826","article-title":"Genipin inhibits TNF-alpha-induced vascular smooth muscle cell proliferation and migration via induction of HO-1","volume":"8","author":"Jiang","year":"2013","journal-title":"PLoS ONE"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"675","DOI":"10.1167\/iovs.03-0351","article-title":"Oxidative stress affects the junctional integrity of retinal pigment epithelial cells","volume":"45","author":"Bailey","year":"2004","journal-title":"Investig. Ophthalmol. Vis. Sci."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1028","DOI":"10.1111\/j.1471-4159.2009.06195.x","article-title":"NADPH oxidase plays a central role in cone cell death in retinitis pigmentosa","volume":"110","author":"Usui","year":"2009","journal-title":"J. Neurochem."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"397","DOI":"10.1016\/S0014-4835(03)00023-X","article-title":"Oxidative stress-induced mitochondrial DNA damage in human retinal pigment epithelial cells: A possible mechanism for RPE aging and age-related macular degeneration","volume":"76","author":"Liang","year":"2003","journal-title":"Exp. Eye Res."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"447","DOI":"10.1016\/j.neuint.2010.12.016","article-title":"Mitochondrial dysfunction in brain aging: Role of oxidative stress and cardiolipin","volume":"58","author":"Paradies","year":"2011","journal-title":"Neurochem. Int."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"336","DOI":"10.1242\/dmm.003178","article-title":"Mitochondrial dysfunction and Parkinson\u2019s disease genes: Insights from Drosophila","volume":"2","author":"Park","year":"2009","journal-title":"Dis. Model. Mech."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"S255","DOI":"10.3233\/JAD-2010-100345","article-title":"Mitochondria dysfunction and neurodegenerative disorders: Cause or Consequence","volume":"20","author":"Morais","year":"2010","journal-title":"J. Alzheimers Dis."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"935","DOI":"10.1016\/j.bbadis.2010.07.014","article-title":"New insights into the role of mitochondrial dysfunction and protein aggregation in Parkinson\u2019s disease","volume":"1802","author":"Xie","year":"2010","journal-title":"Biochim. Biophys. Acta"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1397","DOI":"10.1002\/cmdc.201400051","article-title":"Stereoselective Reduction of 1-O-Isopropyloxygenipin Enhances Its Neuroprotective Activity in Neuronal Cells from Apoptosis Induced by Sodium Nitroprusside","volume":"9","author":"Wang","year":"2014","journal-title":"ChemMedChem"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"730","DOI":"10.1248\/jhs.53.730","article-title":"Characteristic properties of genipin as an activator in neuronal nitric oxide synthase","volume":"53","author":"Suzuki","year":"2007","journal-title":"J. Health Sci."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1232","DOI":"10.1111\/j.1471-4159.2011.07533.x","article-title":"Long-acting genipin derivative protects retinal ganglion cells from oxidative stress models in vitro and in vivo through the Nrf2\/antioxidant response element signaling pathway","volume":"119","author":"Koriyama","year":"2011","journal-title":"J. Neurochem."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1111\/j.1471-4159.2010.06903.x","article-title":"Neuritogenic activity of a genipin derivative in retinal ganglion cells is mediated by retinoic acid receptor beta expression through nitric oxide\/S-nitrosylation signaling","volume":"115","author":"Koriyama","year":"2010","journal-title":"J. Neurochem."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"18179","DOI":"10.1074\/jbc.M411085200","article-title":"Novel dimeric acetylcholinesterase inhibitor bis(7)-tacrine, but not donepezil, prevents glutamate-induced neuronal apoptosis by blocking n-methyl-d-aspartate receptors","volume":"280","author":"Li","year":"2005","journal-title":"J. Biol. Chem."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"353","DOI":"10.1530\/JOE-11-0473","article-title":"SIRT1 represses estrogen-signaling, ligand-independent ER\u03b1-mediated transcription, and cell proliferation in estrogen-responsive breast cells","volume":"216","author":"Ma","year":"2013","journal-title":"J. Endocrinol."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"30","DOI":"10.1016\/S1016-8478(23)07386-7","article-title":"Opposing effects of ERK and p38 MAP kinases on HeLa cell apoptosis induced by dipyrithione","volume":"23","author":"Fan","year":"2007","journal-title":"Mol. Cells"},{"key":"ref_40","first-page":"196","article-title":"Requirement for ERK activity in sodium selenite-induced apoptosis of acute promyelocytic leukemia-derived NB4 cells","volume":"40","author":"Han","year":"2007","journal-title":"J. Biochem. Mol. Biol."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"662","DOI":"10.1038\/sj.bjp.0706370","article-title":"Fundamental role of nitric oxide in neuritogenesis of PC12h cells","volume":"146","author":"Yamazaki","year":"2005","journal-title":"Br. J. Pharmacol."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1016\/j.ejphar.2004.02.009","article-title":"Genipin exhibits neurotrophic effects through a common signaling pathway in nitric oxide synthase-expressing cells","volume":"488","author":"Yamazaki","year":"2004","journal-title":"Eur. J. Pharmacol."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"855","DOI":"10.1074\/jbc.M807914200","article-title":"Glutamate acting on N-methyl-d-aspartate receptors attenuates insulin-like growth factor-1 receptor tyrosine phosphorylation and its survival signaling properties in rat hippocampal neurons","volume":"284","author":"Zheng","year":"2009","journal-title":"J. Biol. Chem."}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/16\/9\/22350\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T20:48:32Z","timestamp":1760215712000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/16\/9\/22350"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2015,9,15]]},"references-count":43,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2015,9]]}},"alternative-id":["ijms160922350"],"URL":"https:\/\/doi.org\/10.3390\/ijms160922350","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2015,9,15]]}}}