This project examined functional changes in neuronal and glial cells and the subsequent interaction and signalling between these cells in the nervous system following perturbation. Although various responses of neural cells exist, this work has focused on two aspects, 1) the ability of the cell to maintain calcium homeostasis which plays a critical regulatory role in cell-cell communication and signalling. A disruption in intracellular calcium can disrupt the calcium-mediated signal transduction processes resulting in a cascade of intracellular effects including alterations in transcription factors and specific mRNAs for cellular proteins. 2) the response of microglia and astrocytes to neural injury and the role for pro-inflammation cytokines, IL-1, IL-6, TNA- alpha, as signalling mechanisms in the cascade of neurotoxicity. Within the nervous system cytokines are thought to have active roles in the pathophysiological changes seen in various neurological diseases and trauma. Early responses to chemical injury suggest a possible involvement of pro-inflammatory cytokines in the signalling process to initiate the injury response cascade of neuronal necrosis, astrogliosis, and subsequent neuronal loss. The interaction between neurons and glia will be investigated by examining the signalling mechanism of cytokines on neuronal cells with regard to calcium homeostasis and gap-junctional communication.

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Intramural Research (Z01)
Project #
1Z01ES021154-05
Application #
5202118
Study Section
Project Start
Project End
Budget Start
Budget End
Support Year
5
Fiscal Year
1995
Total Cost
Indirect Cost
City
State
Country
United States
Zip Code
Harry, G Jean; McPherson, Christopher A; Wine, Robert N et al. (2004) Trimethyltin-induced neurogenesis in the murine hippocampus. Neurotox Res 5:623-7
McPherson, Christopher A; Kubik, Julie; Wine, Robert N et al. (2003) Alterations in cyclin A, B, and D1 in mouse dentate gyrus following TMT-induced hippocampal damage. Neurotox Res 5:339-54
Harry, G Jean; Lefebvre d'Hellencourt, Christian (2003) Dentate gyrus: alterations that occur with hippocampal injury. Neurotoxicology 24:343-56
Harry, G Jean; Tyler, Kelly; d'Hellencourt, Christian Lefebvre et al. (2002) Morphological alterations and elevations in tumor necrosis factor-alpha, interleukin (IL)-1alpha, and IL-6 in mixed glia cultures following exposure to trimethyltin: modulation by proinflammatory cytokine recombinant proteins and neutralizing antibodies. Toxicol Appl Pharmacol 180:205-18
Jahnke, G D; Brunssen, S; Maier, W E et al. (2001) Neurotoxicant-induced elevation of adrenomedullin expression in hippocampus and glia cultures. J Neurosci Res 66:464-74
Harry, G J; Lefebvre d'Hellencourt, C; Bruccoleri, A et al. (2000) Age-dependent cytokine responses: trimethyltin hippocampal injury in wild-type, APOE knockout, and APOE4 mice. Brain Behav Immun 14:288-304
Bruccoleri, A; Harry, G J (2000) Chemical-induced hippocampal neurodegeneration and elevations in TNFalpha, TNFbeta, IL-1alpha, IP-10, and MCP-1 mRNA in osteopetrotic (op/op) mice. J Neurosci Res 62:146-55