Oleanolic Acid Exerts a Neuroprotective Effect Against Microglial Cell Activation by Modulating Cytokine Release and Antioxidant Defense Systems

José M Castellano, Silvia Garcia-Rodriguez, Juan M Espinosa, María C Millan-Linares, Mirela Rada, Javier S Perona, José M Castellano, Silvia Garcia-Rodriguez, Juan M Espinosa, María C Millan-Linares, Mirela Rada, Javier S Perona

Abstract

Microglia respond to adverse stimuli in order to restore brain homeostasis and, upon activation, they release a number of inflammatory mediators. Chronic microglial overactivation is related to neuroinflammation in Alzheimer's disease. In this work, we show that oleanolic acid (OA), a natural triterpene present in food and medicinal plants, attenuates the activation of BV2 microglial cells induced by lipopolysaccharide (LPS). Cell pretreatment with OA inhibited the release of IL-1β, IL-6, TNF-α, and NO, which was associated with the downregulation of the expression of genes encoding for these cytokines and inducible nitric oxide synthase (iNOS), and the reinforcement of the endogenous antioxidant cell defense. These findings advocate considering OA as a novel neuroprotective agent to inhibit oxidative stress and inflammatory response in activated microglia associated with Alzheimer's disease.

Keywords: cytokines; inflammation; microglia; neuroprotection; oleanolic acid; oxidative stress.

Conflict of interest statement

The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

Figures

Figure 1
Figure 1
Chemical structure of the oleanolic acid molecule.
Figure 2
Figure 2
Microphotographs of BV2 microglial cells before (a) and after (b) activation with lipopolysaccharide (LPS).
Figure 3
Figure 3
Inhibition of cytokine production by oleanolic acid (OA) in LPS-induced microglia. (a) interleukin-1β (IL-1β), (b) interleukin-6 (IL-6), and (c) tumor necrosis factor-α (TNF-α). Cells were pretreated with OA for 1 h before LPS treatment for 24 h. Values are expressed as mean ± SD of 3 independent experiments. **, p < 0.01 and ***, p < 0.01 vs. LPS.
Figure 4
Figure 4
Inhibition of cytokine gene expression by oleanolic acid (OA) in LPS-induced microglia: (a) interleukin-1β (IL-1β), (b) interleukin-6 (IL-6), and (c) tumor necorsis factor-α (TNF-α). Cells were pretreated with OA for 1 h before LPS treatment for 24 h. Values are expressed as mean ± SD of 3 independent experiments. *, p < 0.05 and ***, p < 0.001 vs. LPS.
Figure 5
Figure 5
Inhibition of nitrite production (a) and inducible nitric oxide synthase (iNOS) gene expression (b) by oleanolic acid in LPS-induced microglia. Cells were pretreated with OA 1 h before LPS treatment for 24 h. Values are expressed as mean ± SD of 3 independent experiments. *, p < 0.05 and ***, p < 0.001 vs. LPS.
Figure 6
Figure 6
Inhibition of reactive oxygen species (ROS) production by oleanolic acid (OA) in LPS-induced microglia. Cells were pretreated with OA for 1 h before LPS treatment for 24 h. Data are presented as percentage of DCF production. Values are expressed as mean ± SD of 3 independent experiments. *, p < 0.05 vs. LPS.
Figure 7
Figure 7
Increased total intracellular glutathione concentration by oleanolic acid (OA) in LPS-induced microglia. Cells were pretreated with OA for 1 h before LPS treatment for 24 h. Values are expressed as mean ± SD of 3 independent experiments. *, p < 0.05 and **, p < 0.01 vs. LPS.
Figure 8
Figure 8
Graphical summary of the main results obtained.

References

    1. Van Bulck M., Sierra-Magro A., Alarcon-Gil J., Perez-Castillo A., Morales-Garcia J.A. Novel Approaches for the Treatment of Alzheimer’s and Parkinson’s Disease. Int. J. Mol. Sci. 2019;20:719. doi: 10.3390/ijms20030719.
    1. Serrano-Pozo A., Frosch M.P., Masliah E., Hyman B.T. Neuropathological Alterations in Alzheimer Disease. Cold Spring Harb. Perspect. Med. 2011;1:a006189. doi: 10.1101/cshperspect.a006189.
    1. Schott J.M., Revesz T. Inflammation in Alzheimer’s disease: Insights from immunotherapy. Brain. 2013;136:2654–2656. doi: 10.1093/brain/awt231.
    1. Wang X., Wang W., Li L., Perry G., Lee H., Zhu X. Oxidative stress and mitochondrial dysfunction in Alzheimer’s disease. Biochim. Biophys. Acta. 2014;1842:1240–1247. doi: 10.1016/j.bbadis.2013.10.015.
    1. Brookmeyer R., Johnson E., Ziegler-Graham K., Arrighi H.M. Forecasting the global burden of Alzheimer’s disease. Alzheimers Dement. 2007;3:186–191. doi: 10.1016/j.jalz.2007.04.381.
    1. Orsolini L., Sarchione F., Vellante F., Fornaro M., Matarazzo I., Martinotti G., Valchera A., Di Nicola M., Carano A., Di Giannantonio M., et al. Protein-C Reactive as Biomarker Predictor of Schizophrenia Phases of Illness? A Systematic Review. Curr. Neuropharmacol. 2018;16:583–606. doi: 10.2174/1570159X16666180119144538.
    1. De Berardis D., Fornaro M., Orsolini L., Iasevoli F., Tomasetti C., de Bartolomeis A., Serroni N., De Lauretis I., Girinelli G., Mazza M., et al. Effect of agomelatine treatment on C-reactive protein levels in patients with major depressive disorder: An exploratory study in “real-world,” everyday clinical practice. CNS Spectr. 2017;22:342–347. doi: 10.1017/S1092852916000572.
    1. Calvo-Ochoa E., Arias C. Cellular and metabolic alterations in the hippocampus caused by insulin signalling dysfunction and its association with cognitive impairment during aging and Alzheimer’s disease: Studies in animal models. Diabetes. Metab. Res. Rev. 2015;31:1–13. doi: 10.1002/dmrr.2531.
    1. Steen E., Terry B.M., Rivera E.J., Cannon J.L., Neely T.R., Tavares R., Xu X.J., Wands J.R., de la Monte S.M. Impaired insulin and insulin-like growth factor expression and signaling mechanisms in Alzheimer’s disease-is this type 3 diabetes? J. Alzheimers. Dis. 2005;7:63–80. doi: 10.3233/JAD-2005-7107.
    1. Morris M.C., Evans D.A., Bienias J.L., Tangney C.C., Bennett D.A., Wilson R.S., Aggarwal N., Schneider J. Consumption of Fish and n-3 Fatty Acids and Risk of Incident Alzheimer Disease. Arch. Neurol. 2003;60:940–946. doi: 10.1001/archneur.60.7.940.
    1. Pallebage-Gamarallage M.M., Lam V., Takechi R., Galloway S., Mamo J.C.L. A diet enriched in docosahexanoic acid exacerbates brain parenchymal extravasation of Apo B lipoproteins induced by chronic ingestion of saturated fats. Int. J. Vasc. Med. 2012;2012:647689. doi: 10.1155/2012/647689.
    1. Palomer X., Pizarro-Delgado J., Barroso E., Vázquez-Carrera M. Palmitic and Oleic Acid: The Yin and Yang of Fatty Acids in Type 2 Diabetes Mellitus. Trends Endocrinol. Metab. 2018;29:178–190. doi: 10.1016/j.tem.2017.11.009.
    1. Kalmijn S., Launer L.J., Ott A., Witteman J.C.M., Hofman A., Breteler M.M.B. Dietary fat intake and the risk of incident dementia in the Rotterdam study. Ann. Neurol. 1997;42:776–782. doi: 10.1002/ana.410420514.
    1. Dyall S.C. Amyloid-Beta Peptide, Oxidative Stress and Inflammation in Alzheimer’s Disease: Potential Neuroprotective Effects of Omega-3 Polyunsaturated Fatty Acids. Int. J. Alzheimers. Dis. 2010;2010:1–10. doi: 10.4061/2010/274128.
    1. Coll T., Eyre E., Rodríguez-Calvo R., Palomer X., Sánchez R.M., Merlos M., Laguna J.C., Vázquez-Carrera M. Oleate reverses palmitate-induced insulin resistance and inflammation in skeletal muscle cells. J. Biol. Chem. 2008;283:11107–11116. doi: 10.1074/jbc.M708700200.
    1. Henique C., Mansouri A., Fumey G., Lenoir V., Girard J., Bouillaud F., Prip-Buus C., Cohen I. Increased Mitochondrial Fatty Acid Oxidation Is Sufficient to Protect Skeletal Muscle Cells from Palmitate-induced Apoptosis. J. Biol. Chem. 2010;285:36818–36827. doi: 10.1074/jbc.M110.170431.
    1. Day E.A., Ford R.J., Steinberg G.R. AMPK as a Therapeutic Target for Treating Metabolic Diseases. Trends Endocrinol. Metab. 2017;28:545–560. doi: 10.1016/j.tem.2017.05.004.
    1. Molteni R., Barnard R., Ying Z., Roberts C.., Gómez-Pinilla F. A high-fat, refined sugar diet reduces hippocampal brain-derived neurotrophic factor, neuronal plasticity, and learning. Neuroscience. 2002;112:803–814. doi: 10.1016/S0306-4522(02)00123-9.
    1. Stranahan A.M., Norman E.D., Lee K., Cutler R.G., Telljohann R.S., Egan J.M., Mattson M.P. Diet-induced insulin resistance impairs hippocampal synaptic plasticity and cognition in middle-aged rats. Hippocampus. 2008;18:1085–1088. doi: 10.1002/hipo.20470.
    1. Cooper J.L. Dietary lipids in the aetiology of Alzheimer’s disease: Implications for therapy. Drugs Aging. 2003;20:399–418. doi: 10.2165/00002512-200320060-00001.
    1. Granholm A.-C., Bimonte-Nelson H.A., Moore A.B., Nelson M.E., Freeman L.R., Sambamurti K. Effects of a saturated fat and high cholesterol diet on memory and hippocampal morphology in the middle-aged rat. J. Alzheimers. Dis. 2008;14:133–145. doi: 10.3233/JAD-2008-14202.
    1. Spielman L.J., Little J.P., Klegeris A. Physical activity and exercise attenuate neuroinflammation in neurological diseases. Brain. Res. Bull. 2016;125:19–29. doi: 10.1016/j.brainresbull.2016.03.012.
    1. Liu B., Hong J.-S. Role of Microglia in Inflammation-Mediated Neurodegenerative Diseases: Mechanisms and Strategies for Therapeutic Intervention. J. Pharmacol. Exp. Ther. 2003;304:1–7. doi: 10.1124/jpet.102.035048.
    1. McGeer E.G., McGeer P.L. The role of the immune system in neurodegenerative disorders. Mov. Disord. 1997;12:855–858. doi: 10.1002/mds.870120604.
    1. Bhat N.R., Feinstein D.L., Shen Q., Bhat A.N. p38 MAPK-mediated transcriptional activation of inducible nitric-oxide synthase in glial cells. Roles of nuclear factors, nuclear factor kappa B, cAMP response element-binding protein, CCAAT/enhancer-binding protein-beta, and activating transcription factor-2. J. Biol. Chem. 2002;277:29584–29592.
    1. Cui Y., Park J.-Y., Wu J., Lee J.H., Yang Y.-S., Kang M.-S., Jung S.-C., Park J.M., Yoo E.-S., Kim S.-H., et al. Dieckol Attenuates Microglia-mediated Neuronal Cell Death via ERK, Akt and NADPH Oxidase-mediated Pathways. Korean J. Physiol. Pharmacol. 2015;19:219–228. doi: 10.4196/kjpp.2015.19.3.219.
    1. Kharrazi H., Vaisi-Raygani A., Rahimi Z., Tavilani H., Aminian M., Pourmotabbed T. Association between enzymatic and non-enzymatic antioxidant defense mechanism with apolipoprotein E genotypes in Alzheimer disease. Clin. Biochem. 2008;41:932–936. doi: 10.1016/j.clinbiochem.2008.05.001.
    1. Pallebage-Gamarallage M.M.S., Takechi R., Lam V., Galloway S., Dhaliwal S., Mamo J.C.L. Post-prandial lipid metabolism, lipid-modulating agents and cerebrovascular integrity: Implications for dementia risk. Atheroscler. Suppl. 2010;11:49–54. doi: 10.1016/j.atherosclerosissup.2010.04.002.
    1. Takechi R., Pallebage-Gamarallage M.M., Lam V., Giles C., Mamo J.C. Nutraceutical agents with anti-inflammatory properties prevent dietary saturated-fat induced disturbances in blood-brain barrier function in wild-type mice. J. Neuroinflammation. 2013;10:73. doi: 10.1186/1742-2094-10-73.
    1. Park H., Oh M. Houttuyniae Herba protects rat primary cortical cells from Aβ25–35 -induced neurotoxicity via regulation of calcium influx and mitochondria-mediated apoptosis. Hum. Exp. Toxicol. 2012;31:698–709. doi: 10.1177/0960327111433898.
    1. Cho S.O., Ban J.Y., Kim J.Y., Jeong H.Y., Lee I.S., Song K.-S., Bae K., Seong Y.H. Aralia cordata protects against amyloid beta protein (25–35)-induced neurotoxicity in cultured neurons and has antidementia activities in mice. J. Pharmacol. Sci. 2009;111:22–32. doi: 10.1254/jphs.08271FP.
    1. Van Kanegan M.J., He D.N., Dunn D.E., Yang P., Newman R.A., West A.E., Lo D.C. BDNF mediates neuroprotection against oxygen-glucose deprivation by the cardiac glycoside oleandrin. J. Neurosci. 2014;34:963–968. doi: 10.1523/JNEUROSCI.2700-13.2014.
    1. Msibi Z.N.P., Mabandla M.V. Oleanolic Acid Mitigates 6-Hydroxydopamine Neurotoxicity by Attenuating Intracellular ROS in PC12 Cells and Striatal Microglial Activation in Rat Brains. Front. Physiol. 2019;10:1059. doi: 10.3389/fphys.2019.01059.
    1. Jäger S., Trojan H., Kopp T., Laszczyk M.N., Scheffler A. Pentacyclic triterpene distribution in various plants-rich sources for a new group of multi-potent plant extracts. Molecules. 2009;14:2016–2031. doi: 10.3390/molecules14062016.
    1. Guinda A., Rada M., Delgado T., Gutiérrez-Adánez P., Castellano J.M. Pentacyclic triterpenoids from olive fruit and leaf. J. Agric. Food Chem. 2010;58:9685–9691. doi: 10.1021/jf102039t.
    1. Santini A., Novellino E., Armini V., Ritieni A. State of the art of Ready-to-Use Therapeutic Food: A tool for nutraceuticals addition to foodstuff. Food Chem. 2013;140:843–849. doi: 10.1016/j.foodchem.2012.10.098.
    1. Nakamura A., Osonoi T., Terauchi Y. Relationship between urinary sodium excretion and pioglitazone-induced edema. J. Diabetes Investig. 2010;1:208–211. doi: 10.1111/j.2040-1124.2010.00046.x.
    1. Santos-Lozano J.M., Rada M., Lapetra J., Guinda Á., Jiménez-Rodríguez M.C., Cayuela J.A., Ángel-Lugo A., Vilches-Arenas Á., Gómez-Martín A.M., Ortega-Calvo M., et al. Prevention of type 2 diabetes in prediabetic patients by using functional olive oil enriched in oleanolic acid: The PREDIABOLE study, a randomized controlled trial. Diabetes Obes. Metab. 2019;21(11):2526–2534. doi: 10.1111/dom.13838.
    1. Daliu P., Santini A., Novellino E. A decade of nutraceutical patents: Where are we now in 2018? Expert Opin. Ther. Pat. 2018;28:875–882. doi: 10.1080/13543776.2018.1552260.
    1. Durazzo A. Extractable and Non-extractable polyphenols: An overview. In: Saura-Calixto F., Pérez-Jiménez J., editors. Non-Extractable Polyphenols and Carotenoids: Importance in Human Nutrition and Health. Royal Society of Chemistry; London, UK: 2018. pp. 1–37.
    1. Albi T., Guinda Garín M.Á., Lanzón A. Procedimiento de obtención y determinación de ácidos terpénicos de la hoja de olivo (Olea europaea) Grasas y Aceites. 2001;52:275–278.
    1. Rada M., Castellano J.M., Perona J.S., Guinda A. GC-FID determination and pharmacokinetic studies of oleanolic acid in human serum. Biomed. Chromatogr. 2015;29:1687–1692. doi: 10.1002/bmc.3480.
    1. Stockert J.C., Horobin R.W., Colombo L.L., Blázquez-Castro A. Tetrazolium salts and formazan products in Cell Biology: Viability assessment, fluorescence imaging, and labeling perspectives. Acta Histochem. 2018;120:159–167. doi: 10.1016/j.acthis.2018.02.005.
    1. Rose S., Melnyk S., Trusty T.A., Pavliv O., Seidel L., Li J., Nick T., James S.J. Intracellular and extracellular redox status and free radical generation in primary immune cells from children with autism. Autism Res. Treat. 2012;2012:986519. doi: 10.1155/2012/986519.
    1. Giustarini D., Dalle-Donne I., Milzani A., Fanti P., Rossi R. Analysis of GSH and GSSG after derivatization with N-ethylmaleimide. Nat. Protoc. 2013;8:1660–1669. doi: 10.1038/nprot.2013.095.
    1. Ransohoff R.M. How neuroinflammation contributes to neurodegeneration. Science. 2016;353:777–783. doi: 10.1126/science.aag2590.
    1. Sadraie S., Kiasalari Z., Razavian M., Azimi S., Sedighnejad L., Afshin-Majd S., Baluchnejadmojarad T., Roghani M. Berberine ameliorates lipopolysaccharide-induced learning and memory deficit in the rat: Insights into underlying molecular mechanisms. Metab. Brain Dis. 2019;34:245–255. doi: 10.1007/s11011-018-0349-5.
    1. Asiimwe N., Yeo S.G., Kim M.-S., Jung J., Jeong N.Y. Nitric Oxide: Exploring the Contextual Link with Alzheimer’s Disease. Oxid. Med. Cell. Longev. 2016;2016:7205747. doi: 10.1155/2016/7205747.
    1. Bredt D.S., Snyder S.H. Nitric Oxide: A Physiologic Messenger Molecule. Annu. Rev. Biochem. 1994;63:175–195. doi: 10.1146/annurev.bi.63.070194.001135.
    1. Wang J., Zhang T., Liu X., Fan H., Wei C. Aqueous extracts of se-enriched Auricularia auricular attenuates D-galactose-induced cognitive deficits, oxidative stress and neuroinflammation via suppressing RAGE/MAPK/NF-κB pathway. Neurosci. Lett. 2019;704:106–111. doi: 10.1016/j.neulet.2019.04.002.
    1. Castellano J.M., Guinda A., Macías L., Santos-Lozano J.M., Lapetra J., Rada M. Free radical scavenging and α-glucosidase inhibition, two potential mechanisms involved in the anti-diabetic activity of oleanolic acid. Grasas y Aceites. 2016;67:e142. doi: 10.3989/gya.1237153.
    1. Castellano J.M., Guinda A., Delgado T., Rada M., Cayuela J.A. Biochemical basis of the antidiabetic activity of oleanolic acid and related pentacyclic triterpenes. Diabetes. 2013;62:1791–1799. doi: 10.2337/db12-1215.
    1. Dinkova-Kostova A.T., Liby K.T., Stephenson K.K., Holtzclaw W.D., Gao X., Suh N., Williams C., Risingsong R., Honda T., Gribble G.W., et al. Extremely potent triterpenoid inducers of the phase 2 response: Correlations of protection against oxidant and inflammatory stress. Proc. Natl. Acad. Sci. USA. 2005;102:4584–4589. doi: 10.1073/pnas.0500815102.
    1. Matumba M.G., Ayeleso A.O., Nyakudya T., Erlwanger K., Chegou N.N., Mukwevho E., Matumba M.G., Ayeleso A.O., Nyakudya T., Erlwanger K., et al. Long-Term Impact of Neonatal Intake of Oleanolic Acid on the Expression of AMP-Activated Protein Kinase, Adiponectin and Inflammatory Cytokines in Rats Fed with a High Fructose Diet. Nutrients. 2019;11:226. doi: 10.3390/nu11020226.
    1. Fan H.-H.H., Zhu L.-B.B., Li T., Zhu H., Wang Y.-N.N., Ren X.-L.L., Hu B.-L.L., Huang C.-P.P., Zhu J.-H.H., Zhang X. Hyperoside inhibits lipopolysaccharide-induced inflammatory responses in microglial cells via p38 and NFκB pathways. Int. Immunopharmacol. 2017;50:14–21. doi: 10.1016/j.intimp.2017.06.004.
    1. Shih M.-F., Cheng Y.-D., Shen C.-R., Cherng J.-Y. A molecular pharmacology study into the anti-inflammatory actions of Euphorbia hirta L. on the LPS-induced RAW 264.7 cells through selective iNOS protein inhibition. J. Nat. Med. 2010;64:330–335. doi: 10.1007/s11418-010-0417-6.
    1. Simão da Silva K.A.B., Paszcuk A.F., Passos G.F., Silva E.S., Bento A.F., Meotti F.C., Calixto J.B. Activation of cannabinoid receptors by the pentacyclic triterpene α,β-amyrin inhibits inflammatory and neuropathic persistent pain in mice. Pain. 2011;152:1872–1887. doi: 10.1016/j.pain.2011.04.005.
    1. Cabral G.A., Marciano-Cabral F. Cannabinoid receptors in microglia of the central nervous system: Immune functional relevance. J. Leukoc. Biol. 2005;78:1192–1197. doi: 10.1189/jlb.0405216.
    1. Cha H.J., Park M.T., Chung H.Y., Kim N.D., Sato H., Seiki M., Kim K.W. Ursolic acid-induced down-regulation of MMP-9 gene is mediated through the nuclear translocation of glucocorticoid receptor in HT1080 human fibrosarcoma cells. Oncogene. 1998;16:771–778. doi: 10.1038/sj.onc.1201587.
    1. Cho N., Moon E.H., Kim H.W., Hong J., Beutler J.A., Sung S.H. Inhibition of Nitric Oxide Production in BV2 Microglial Cells by Triterpenes from Tetrapanax papyriferus. Molecules. 2016;21:459. doi: 10.3390/molecules21040459.
    1. Liu R.-P., Zou M., Wang J.-Y., Zhu J.-J., Lai J.-M., Zhou L.-L., Chen S.-F., Zhang X., Zhu J.-H. Paroxetine ameliorates lipopolysaccharide-induced microglia activation via differential regulation of MAPK signaling. J. Neuroinflammation. 2014;11:47. doi: 10.1186/1742-2094-11-47.
    1. Tsai S.-J., Yin M.-C. Antioxidative and anti-inflammatory protection of oleanolic acid and ursolic acid in PC12 cells. J. Food Sci. 2008;73:H174–H178. doi: 10.1111/j.1750-3841.2008.00864.x.
    1. Soobrattee M.A., Neergheen V.S., Luximon-Ramma A., Aruoma O.I., Bahorun T. Phenolics as potential antioxidant therapeutic agents: Mechanism and actions. Mutat. Res. 2005;579:200–213. doi: 10.1016/j.mrfmmm.2005.03.023.
    1. Li Q., Verma I.M. NF-kappaB regulation in the immune system. Nat. Rev. Immunol. 2002;2:725–734. doi: 10.1038/nri910.
    1. Takada K., Nakane T., Masuda K., Ishii H. Ursolic acid and oleanolic acid, members of pentacyclic triterpenoid acids, suppress TNF-α-induced E-selectin expression by cultured umbilical vein endothelial cells. Phytomedicine. 2010;17:1114–1119. doi: 10.1016/j.phymed.2010.04.006.
    1. Saaby L., Jäger A.K., Moesby L., Hansen E.W., Christensen S.B. Isolation of immunomodulatory triterpene acids from a standardized rose hip powder (Rosa canina L.) Phytother. Res. 2011;25:195–201. doi: 10.1002/ptr.3241.
    1. Huang T.H.W., Yang Q., Harada M., Li G.Q., Yamahara J., Roufogalis B.D., Li Y. Pomegranate flower extract diminishes cardiac fibrosis in Zucker diabetic fatty rats: Modulation of cardiac endothelin-1 and nuclear factor-kappaB pathways. J. Cardiovasc. Pharmacol. 2005;46:856–862. doi: 10.1097/01.fjc.0000190489.85058.7e.
    1. Feng J., Zhang P., Chen X., He G. PI3K and ERK/Nrf2 pathways are involved in oleanolic acid-induced heme oxygenase-1 expression in rat vascular smooth muscle cells. J. Cell. Biochem. 2011;112:1524–1531. doi: 10.1002/jcb.23065.
    1. Zeng X.-Y., Wang Y.-P., Cantley J., Iseli T.J., Molero J.C., Hegarty B.D., Kraegen E.W., Ye Y., Ye J.-M. Oleanolic acid reduces hyperglycemia beyond treatment period with Akt/FoxO1-induced suppression of hepatic gluconeogenesis in type-2 diabetic mice. PLoS ONE. 2012;7:e42115. doi: 10.1371/journal.pone.0042115.

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