Inhibitors of brain phospholipase A2 activity: their neuropharmacological effects and therapeutic importance for the treatment of neurologic disorders.
The phospholipase A(2) family includes secretory phospholipase A(2), cytosolic phospholipase A(2), plasmalogen-selective phospholipase A(2), and calcium-independent phospholipase A(2). It is generally thought that the release of arachidonic acid by cytosolic phospholipase A(2) is the rate-limiting step in the generation of eicosanoids and platelet activating factor. These lipid mediators play critical roles in the initiation and modulation of inflammation and oxidative stress. Neurological disorders, such as ischemia, spinal cord injury, Alzheimer's disease, multiple sclerosis, prion diseases, and epilepsy are characterized by inflammatory reactions, oxidative stress, altered phospholipid metabolism, accumulation of lipid peroxides, and increased phospholipase A(2) activity. Increased activities of phospholipases A(2) and generation of lipid mediators may be involved in oxidative stress and neuroinflammation associated with the above neurological disorders. Several phospholipase A(2) inhibitors have been recently discovered and used for the treatment of ischemia and other neurological diseases in cell culture and animal models. At this time very little is known about in vivo neurochemical effects, mechanism of action, or toxicity of phospholipase A(2) inhibitors in human or animal models of neurological disorders. In kainic acid-mediated neurotoxicity, the activities of phospholipase A(2) isoforms and their immunoreactivities are markedly increased and phospholipase A(2) inhibitors, quinacrine and chloroquine, arachidonyl trifluoromethyl ketone, bromoenol lactone, cytidine 5-diphosphoamines, and vitamin E, not only inhibit phospholipase A(2) activity and immunoreactivity but also prevent neurodegeneration, suggesting that phospholipase A(2) is involved in the neurodegenerative process. This also suggests that phospholipase A(2) inhibitors can be used as neuroprotectants and anti-inflammatory agents against neurodegenerative processes in neurodegenerative diseases.
Farooqui
Akhlaq A
AA
Department of Molecular and Cellular Biochemistry, The Ohio State University, 1645 Neil Avenue, Columbus, OH 43210-1218, USA.
Ong
Wei-Yi
WY
Horrocks
Lloyd A
LA
D000818:Animals; D001798:Blood Proteins / Q000494:pharmacology* / Q000502:physiology / Q000627:therapeutic use*; D001921:Brain / Q000201:enzymology*; D001930:Brain Injuries / Q000139:chemically induced / Q000517:prevention & control / Q000534:rehabilitation; D006801:Humans; D007608:Kainic Acid / Q000009:adverse effects; D008954:Models, Biological; D009422:Nervous System Diseases / Q000188:drug therapy* / Q000201:enzymology; D009474:Neurons / Q000187:drug effects; D010146:Pain / Q000188:drug therapy / Q000517:prevention & control; D010741:Phospholipases A / Q000378:metabolism* / Q000502:physiology; D054467:Phospholipases A2
D001798:Blood Proteins; C400481:PLIalpha; D010741:Phospholipases A; D054467:Phospholipases A2; D007608:Kainic Acid