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| Degrees |
1996-1998: Postdoc, Washington University, St. Louis, MO |
| Bio |
Awards/Recognitions/Lectures 2007 to 2008: Alzheimer’s Disease Research Center small pilot grant My lab studies the death induced by excess zinc which occurs after injuries and pathophysiologic conditions in neurons and beta-cells. Primary cortical neuronal cultures exposed to Zn2+ had reduced levels of ATP, and NAD+, while glycolytic intermediates, and lactate levels increased. Measures which restored the NAD+ levels, such as exogenous addition of NAD+, nicotinamide, or pyruvate prevented zinc-induced death, and a measure which increased the loss of NAD+ (3-AP) potentiated death. The sirtuin pathway is involved because the inhibitor, sirtinol, attenuated injury, and the activator, resveratrol, potentiated injury. Further implicating the role of NAD+ levels, neurons from Wlds mice (which overexpress an NAD+ synthetic enzyme) were resistant to Zn2+ toxicity. These in vitro systems serve as a model of ischemic neurodegeneration in vivo. We and others have demonstrated that nicotinamide, pyruvate, or CaEDTA attenuated neuronal death induced by retinal ischemia, global ischemia, focal ischemia, hypoglycemia, seizures, and head trauma in vivo. This research was funded by an R01 grant from NINDS. Intracellular release of Zn2+, loss of NAD+ levels, and the sirtuin pathway are also involved in reactive oxygen species (ROS) mediated neuronal injuries including serum deprivation (in vitro) and target deprivation (in vivo). Pre-loading neuronal cultures with physiologic levels of Zn2+ potentiated ROS and serum deprivation mediated death, whereas Zn2+ chelation attenuated death. Neuroprotection was similarly afforded by compounds which restored NAD+. Using the in vivo model of lateral geniculate nucleus target deprivation induced by visual cortex ablation (VCA), it was shown that Zn2+ toxicity likely plays a role. We have now shown that i.p. injection of pyruvate or nicotinamide, or direct lesion application of CaEDTA or NAD+ reduced LGN neuronal death 7 days later. Furthermore, Wlds mice demonstrated greatly reduced LGN neuronal death after VCA. We will investigate the role of these Zn2+-mediated mechanisms after global and retinal ischemias, and VCA using mouse genetic models to manipulate Zn2+ and NAD+ levels. R01 grant applications to fund these studies are pending with NINDS and NEI. |
| Clinical Interests |
Current Research
Zn2+ neurotoxicity: role of NAD+ loss and glycolytic inhibition in vitro and in vivo.Zn2+ neurotoxicity has been shown to be involved in neuronal injury from global, focal, and retinal ischemias as well as head trauma, seizures, neuronal target deprivation, and hypoglycemia. Exogenous Zn2+ or Zn2+ released intracellularly because of oxidant conditions appear to have similar mechanisms of toxicity. NAD+ is lost resulting in glycolytic inhibition, and compounds or genotypes which can attenuate the NAD+ loss also attenuate glycolytic inhibition and neuronal death. Exogenous addition of NAD+ restores intracellular NAD+ as do, the conversion of pyruvate to lactate, and the synthesis of NAD+ from nicotinamide by NMNAT1. The sirtuin family of NAD+ dependent protein deacetylases appear to be involved as activators potentiate, and inhibitors attenuate death. We use in vitro culture of primary neurons as well as in vivo models of global, focal, and retinal ischemias and a model of target deprivation to study these processes. Techniques used include molecular biology to manipulate individual pathways by viral or transgenic means, biochemical measurements, and pharmacologic development of therapeutics.
SD means serum deprivation, GD means glucose deprivation, ROS means reactive oxygen species, ETH means ethacrynic acid (ROS generator), DTDP means dithiodipyridine (a thiol oxidizing agent), VGCC means voltage gated Ca2+ channel, MT-III means metallothionein III, G-3-P, FBP, and DHAP are glycolytic intermediates preceding GAPDH (glyceraldehyde-3 phosphate dehydrogenase), 3-AP means 3-acetylpyridine (inactivates NAD+), sirtinol and 2-hydroxy naphthaldehyde are inhibitors, and fisetin and resveratrol are activators of the sirtuin pathway, Mito means mitchondria. |
| Research Interests |
Neurotoxicity and Neuroprotection in Disease States |
| Selected Publications |
Key Recent Papers Sheline, C.T., Shi, C., Takata, T., Zhu, J., Xhang, W., Sheline, P.J., and Cai, A.L. (2009) NOD Mice Demonstrated Toxic b-cell Zn2+ Staining; Pyruvate Attenuated b-Cell Death and Diabetic Incidence In Vivo. AJP, in submission. Sheline, C.T., Shi, C., and Cai, A.L. (2009) Oxidative Neuronal Injuries and Target Deprivation: Role of Zn2+, NAD+, and the Sirtuin Pathway. Journal Neuroscience, in submission. Cai, A.L., Zipfel, G.J., and Sheline, C.T. (2006) Zinc Neurotoxicity Is Dependent on Intracellular NAD+ Levels and the Sirtuin Pathway. European Journal of Neuroscience 24: 2169-2176. Sheline, C.T., and Ling Wei (2006) Free Radical Mediated Toxicity May Be Caused By Inhibition of Mitochondrial Dehydrogenases In Vitro and In Vivo. Neurosci. 140: 235-246. Sheline, C.T., and Dennis W. Choi (2004) Copper-Mediated Toxicity May Be Caused By Inhibition of Mitochondrial Dehydrogenases In Vitro and In Vivo. Ann. Neuro. 55: 645-53. Sheline, C. T., Takata, T., Ying, H., Canzoniero, L.M. T., Yang, A., Yu, S.P., and Choi, D.W. (2004) Potassium Attenuates Zinc-Induced Death of Cultured Cortical Astrocytes. Glia 46:18-27. Sheline, C.T., Wang, H., Cai, A.-L., Dawson, V.L., and Dennis W. Choi (2003) Involvement of Poly-ADP Ribosyl Polymerase-1 in Fast But Not Slow Zinc Neurotoxicity. Eur. J. Neurosci 18:1402-9. Sheline C. T., Ying H. S., Ling C. S., Canzoniero L. M. T., Choi D. W. (2002) Depolarization-Induced 65Zinc Influx into Cultured Cortical Neurons. Neurobiol. Dis.10:41-53. Sheline C. T., Behrens M. M., Choi D. W. (2000) Zinc-induced cortical neuronal death: contribution of energy failure attributable to loss of NAD(+) and inhibition of glycolysis. Journal of Neuroscience 20(9): 3139-46. Okamoto, H., Sheline, C.T., Corden, J.L., Jones, K.A., Peterlin, B.M. (1996) Trans-activation by human immunodeficiency virus tat protein requires the c-terminal domain of RNA polymerase II. PNAS 93(21):11575-9. Selected Papers Suh, S.W., Won, S.J., Hamby, A.M., Fan, Y., Sheline, C.T., and Liu, J., Hypoglycemia induced neuronal death requires synaptic zinc., In Press, JCBFM., 2008. Suh, S.W., Won, S.J., Hamby, A.M., Fan, Y., Sheline, C.T., Tamano, H., Takeda, H., and Liu, J., Decreased brain zinc availability reduces hippocampal neurogenesis., J. Neurosci, in submission., 2008. |
| Additional Info |
Funding “Type-1 Diabetes: Zn2+ Potentiated b-Cell Death By Sirtuin-Mediated NAD+ Loss” |

