salvianolic-acid-B and Cognition-Disorders

Salvianolic acid B (SalB) is a polyphenolic compound found in Salvia miltiorrhiza Bunge that has several anti-oxidative and anti-inflammatory effects. In the present study, we investigated whether SalB has neuroprotective effects in an amyloid β (Aβ) peptide-induced Alzheimer's disease mouse model. Mice were injected with Aβ25-35 peptide intracerebroventricularly and were subsequently administered SalB once daily for 7 days. Subchronic SalB administration (10mg/kg) significantly ameliorated the Aβ25-35 peptide-induced memory impairment in the passive avoidance task (P<0.05). SalB treatment also reduced the number of activated microglia and astrocytes that were observed during the inflammatory reaction after the administration of the Aβ25-35 peptide. Moreover, SalB markedly reduced inducible nitric oxide synthase and cyclooxygenase-2 expression levels and thiobarbituric acid reactive substances, which were increased by the administration of the Aβ25-35 peptide. Furthermore, SalB administration significantly rescued the Aβ25-35 peptide-induced decrease of choline acetyltransferase and brain-derived neurotrophic factor protein levels. These results suggest that SalB exerts neuroprotective activity via anti-inflammatory and anti-oxidative effects and that SalB may be a potential candidate for Alzheimer's disease therapy.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; Anti-Inflammatory Agents; Avoidance Learning; Behavior, Animal; Benzofurans; Brain-Derived Neurotrophic Factor; Choline O-Acetyltransferase; Cognition Disorders; Cyclooxygenase 2; Disease Models, Animal; Hippocampus; Lipid Peroxidation; Male; Mice; Mice, Inbred ICR; Neuroglia; Neuroprotective Agents; Nitric Oxide Synthase Type II; Peptide Fragments

Alzheimer's disease (AD) is a neurodegenerative disorder associated with progressive cognitive and memory loss and neuronal cell death. Current therapeutic strategies for AD are very limited; thus, traditional herbal medicines or their active constituents receive much attention. The aim of this study was to investigate the cognitive enhancing effects of salvianolic acid B (SalB) isolated from Salvia miltiorrhiza and its ameliorating effects on various drug-induced amnesic models using the passive avoidance, Y-maze, and Morris water maze tasks. Drug-induced amnesia was induced by administering scopolamine, diazepam, muscimol, or amyloid-β (Aβ)(25-35) peptide. SalB (10 mg/kg, p.o.) was found to significantly reverse the cognitive impairments induced by scopolamine (1 mg/kg, i.p.) or Aβ(25-35) (10 nmol/5 μl, i.c.v.) injection. This ameliorating effect of SalB was antagonized by the GABA(A) receptor agonists, muscimol or diazepam, respectively. In addition, SalB alone was capable of improving cognitive performances. Furthermore, SalB (100 μM) was found to inhibit GABA-induced outward Cl(-) currents in single hippocampal CA1 neuron. These results suggest that the observed ameliorations of cholinergic dysfunction- or Aβ(25-35)-induced memory impairment by SalB were mediated, in part, via the GABAergic neurotransmitter system after a single administration.

Topics: Amyloid beta-Peptides; Animals; Animals, Newborn; Benzofurans; Cholinergic Antagonists; Cholinesterase Inhibitors; Cognition Disorders; Disease Models, Animal; Dose-Response Relationship, Drug; Female; gamma-Aminobutyric Acid; Hippocampus; In Vitro Techniques; Injections, Intraventricular; Male; Maze Learning; Membrane Potentials; Mice; Neurons; Patch-Clamp Techniques; Peptide Fragments; Pregnancy; Rats; Tacrine