aurapten and Memory-Disorders

We have recently shown that 3,5,6,7,8,3',4'-heptamethoxyflavone (HMF) and auraptene (AUR) have neuroprotective effects on the central nervous system. HMF, a citrus flavonoid, altered NMDA-type glutamate receptor antagonist MK-801-induced memory dysfunction and schizophrenia-positive symptom-like behavior. HMF also showed a protective effect against ischemia-induced short-term memory dysfunction. In the ischemic brain, HMF induced the following protective effects against brain dysfunction: 1) rescue of neuronal cell death in the hippocampus; 2) increased production of brain-derived neurotrophic factor; 3) stimulation of neurogenesis in the dentate gyrus subgranular zone; 4) activation of the autophosphorylation of calcium-calmodulin-dependent protein kinase II; and 5) suppression of microglial activation. On the other hand, AUR, a citrus coumarin, ameliorated lipopolysaccharide-induced inflammation in the brain as shown by inhibition of microglial activation and inhibition of cyclooxygenase (COX)-2 expression in the hippocampus. AUR also showed antiinflammatory effects on the ischemic brain by inhibiting microglial activation, COX-2 expression, and neuronal cell death in the hippocampus. The peel of kawachibankan (Citrus kawachiensis), a noted citrus product of Ehime prefecture, Japan, contains AUR, HMF, naringin, and narirutin. The dried powder of both the peel and juice had antiinflammatory effects in the mouse hippocampus, suggesting that citrus compounds may be beneficial as neuroprotective agents in the treatment of neurological disorders.

Topics: Animals; Anti-Inflammatory Agents; Brain; Brain Ischemia; Brain-Derived Neurotrophic Factor; Calcium-Calmodulin-Dependent Protein Kinase Type 2; Cell Death; Central Nervous System; Citrus; Coumarins; Cyclooxygenase 2; Disease Models, Animal; Flavones; Food; Hippocampus; Humans; Memory Disorders; Mice; Microglia; Nervous System Diseases; Neurogenesis; Neuroprotective Agents; Phytotherapy; Receptors, N-Methyl-D-Aspartate; Schizophrenia

Our aim was to investigate the effects of resveratrol, auraptene, and curcumin on the spatial learning and spatial memory retention in the Morris water maze (MWM). The effects of 4-day bilateral intrahippocampal (i.h.) infusions of dimethyl sulfoxide (DMSO), H-89 as a protein kinase AII inhibitor, auraptene/H-89, resveratrol/H-89, and curcumin/H-89 were investigated on spatial memory acquisition in MWM. The rats were trained for 4 days; each day included one block of four trials. Post-training probe tests were performed on day 5 in acquisition test. For retention assessments, different animals were trained for 4 days and then infused (i.h.) with either DMSO, H-89, auraptene/H-89, resveratrol/H-89, or curcumin/H-89. The retention test was performed 48 h after the last training trial. The bilateral infusion of H-89 led to a significant impairment in spatial memory in acquisition and retention tests accompanied with a significant decrease in expressions of cAMP response-element binding (CREB) and pCREB proteins in hippocampus. Resveratrol and curcumin reversed the H-89-induced spatial memory acquisition and retention impairments with significant increases in both CREB and pCREB proteins expressions compared to H-89-treated animals. Auraptene showed significant effects in reversing H-89-induced impairments in spatial memory retention but not spatial memory acquisition.

Topics: Animals; Coumarins; Curcumin; Cyclic AMP Response Element-Binding Protein; Hippocampus; Infusions, Parenteral; Isoquinolines; Male; Memory; Memory Disorders; Neuroprotective Agents; Rats, Wistar; Resveratrol; Sulfonamides