............................................................................................................................... ii Acknowledgments.............................................................................................................. iii Abbreviations ...................................................................................................................... xi Chapter One: Introduction ................................................................................................... 1 1.1 Neuroprotection ........................................................................................................ 1 1.1.1 Research on Neuroprotection – An Overview ................................................... 1 1.1.2 Alkaloids as Neuroprotectants ........................................................................... 2 1.2 The Global Ageing Population ................................................................................. 4 1.3 Neurodegenerative Disease ....................................................................................... 4 1.3.1 Neurodegeneration and Age Based Relationship ................................................... 4 1.3.2 Excitotoxicity .......................................................................................................... 5 A. Glutamate ................................................................................................................ 5 B. Calcium ................................................................................................................... 6 C. Apoptosis and Necrosis ........................................................................................... 9 1.3.3 Common Disease States ........................................................................................ 11 A. Alzheimer’s Disease (AD) .................................................................................... 11 B. Parkinson’s Disease (PD) ...................................................................................... 11 C. Amyotrophic Lateral Sclerosis (ALS)................................................................... 12 D. Huntington’s Disease (HD) ................................................................................... 13 E. Stroke ..................................................................................................................... 13 1.4 Aim of the Current Project ........................................................................................... 14 Chapter Two: Mescengricin ............................................................................................... 15 2.1 α-Carboline Natural Products ...................................................................................... 15 2.1.1 Grossularine-1 and Grossularine-2 ....................................................................... 15