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The glutamate receptor was one of the most intensely investigated targets for neuroprotection. However, numerous clinical trials of glutamate receptor antagonists for the treatment of stroke were unsuccessful. These failures have led to pessimism in the field. But recent advances could provide hope for the future. This minireview looks beyond the traditional mechanism of glutamate-receptor-driven excitotoxicity to identify other mechanisms of ionic imbalance. These advances include findings implicating sodium-calcium exchangers, hemi-channels, volume-regulated anion channels, acid-sensing channels, transient receptor potential channels, nonselective cation channels and signaling cascades that mediate crosstalk between redundant pathways of cell death. Further in vivo validation of these pathways could ultimately lead us to new therapeutic targets for stroke, trauma and neurodegeneration.

The classical divide between degenerative and inflammatory disorders of the CNS is vanishing as accumulating evidence shows that inflammatory processes are important in the pathophysiology of primarily degenerative disorders, and neurodegeneration complicates primarily inflammatory diseases of the brain and spinal cord. Here, we review the contribution of degenerative and inflammatory processes to CNS disorders such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis and HIV-associated dementia. An early combination of neuroprotective and anti-inflammatory approaches to these disorders seems particularly desirable because isolated treatment of one pathological process might worsen another. We also discuss the apparently unique opportunity to modify neurodegeneration and neuroinflammation simultaneously by pharmacological manipulation of the endocannabinoid system in the CNS and in peripheral immune cells. Current knowledge of this system and its involvement in the above CNS disorders are also reviewed.

Individuals with neurodegenerative diseases such as Parkinson's disease or Alzheimer's disease are benefiting from drugs developed to act on a single molecular target. However, current pharmacological approaches are limited in their ability to modify significantly the course of the disease, and offer incomplete and transient benefit to patients. New therapeutic strategies comprise drug candidates designed specifically to act on multiple neural and biochemical targets for the treatment of cognition impairment, motor dysfunction, depression and neurodegeneration. Examples include the development of single molecular entities that combine two or more of the following properties: (i) cholinesterase inhibition; (ii) activation or inhibition of specific subtypes of acetylcholine receptors or [alpha]-adrenoceptors; (iii) anti-inflammatory activity; (iv) monoamine oxidase inhibition; (v) catechoI-O-methyl transferase inhibition; (vi) nitric oxide production; (vii) neuroprotection; (viii) anti-apoptotic activity; and (ix) activation of mitochondrial-dependent cell-survival genes and proteins. These bi- or multi-functional compounds might provide greater symptomatic efficacy, and better utility as potential neuroprotective disease-modifying drugs.