Michael P. McDonald, Ph.D.
Department of Neurology
The University of Tennessee Health Science Center
855 Monroe Avenue, Suite 415
Memphis, TN 38163
Phone: (901) 448-4648
Fax: (901) 448-4685
Office: 422 Wittenborg Anatomy Building
Email: Michael P. McDonald
Our lab studies the involvement of gangliosides in the behavioral and cognitive impairments, protein misfolding, and neurodegeneration of Alzheimer's and Parkinson's diseases. Gangliosides are glycolipids richly expressed in neuronal membranes. Although the functions of gangliosides are not completely understood, converging evidence clearly demonstrates a critical role for membrane gangliosides in the binding and aggregation of amyloid-β (Aβ), the toxic peptide that aggregates into plaques in Alzheimer's disease. Our previous research showed that elimination of the GD3 synthase (GD3S) gene significantly reduces Aβ binding and Aβ -induced cell death in primary neuronal cultures. In a mutant mouse model of Alzheimer's disease, knocking out GD3S nearly eliminates plaque formation and Aβ -associated neuropathology, and reverses memory deficits. Because GD3 ganglioside is a critical mediator of the ceramide-sphingomyelin-mediated apoptotic pathway, we expect that inhibiting GD3S will also be neuroprotective in models of Parkinson's disease. In addition to targeted mutation of GD3S, ongoing experiments involve injection of viral-vector-mediated small-interfering RNA (siRNA) constructs to "silence" GD3S, and intracranial infusion of v. cholerae sialidase (VCS), an enzyme that hydrolyzes specific sialic acid residues on gangliosides. Both of these manipulations have the effect of reducing levels of the more-complex brain gangliosides, which have a high affinity for Aβ, and increasing levels of the less-complex brain gangliosides, which have a lower affinity for Aβ and are neuroprotective. We expect this line of research to provide insight into new therapeutic targets for Alzheimer's and Parkinson's diseases.
- Wang B, Liu Y, Huang L, Chen J, Li JJ, Wang R, Kim E, Chen Y, Justicia C, Sakata K, Chen H, Planas A, Ostrom RS, Li W, Yang G, McDonald MP, Chen R, Heck DH, Liao FF. A CNS-permeable Hsp90 inhibitor rescues synaptic dysfunction and memory loss in APP-overexpressing Alzheimer's mouse model via an HSF1-mediated mechanism. Mol Psychiatry. 2016 Jul 26. doi: 10.1038/mp.2016.104. PubMed PMID: 27457810.
- Maiti P, Gregg LC, McDonald MP. MPTP-induced executive dysfunction is associated with altered prefrontal serotonergic function. Behav Brain Res. 2016 Feb 1;298(Pt B):192-201. doi: 10.1016/j.bbr.2015.09.014. PubMed PMID: 26393431; PubMed Central PMCID: PMC4803113.
- Tan XL, Xue YQ, Ma T, Wang X, Li JJ, Lan L, Malik KU, McDonald MP, Dopico AM, Liao FF. Partial eNOS deficiency causes spontaneous thrombotic cerebral infarction, amyloid angiopathy and cognitive impairment. Mol Neurodegener. 2015 Jun 24;10:24. doi: 10.1186/s13024-015-0020-0. PubMed PMID: 26104027; PubMed Central PMCID: PMC4479241.
- Rao SK, Ross JM, Harrison FE, Bernardo A, Reiserer RS, Reiserer RS, Mobley JA, McDonald MP. Differential proteomic and behavioral effects of long-term voluntary exercise in wild-type and APP-overexpressing transgenics. Neurobiol Dis. 2015 Jun;78:45-55. doi: 10.1016/j.nbd.2015.03.018. PubMed PMID: 25818006; PubMed Central PMCID: PMC4426078.
- Maiti P, Manna J, McDonald MP. Merging advanced technologies with classical methods to uncover dendritic spine dynamics: A hot spot of synaptic plasticity. Neurosci Res. 2015 Jul;96:1-13. doi: 10.1016/j.neures.2015.02.007. Review. PubMed PMID: 25728560.
- Flanigan TJ, Xue Y, Kishan Rao S, Dhanushkodi A, McDonald MP. Abnormal vibrissa-related behavior and loss of barrel field inhibitory neurons in 5xFAD transgenics. Genes Brain Behav. 2014 Jun;13(5):488-500. doi: 10.1111/gbb.12133. PubMed PMID: 24655396; PubMed Central PMCID: PMC4170055.