Icariin inhibits the increased inward calcium currents induced by amyloid-beta(25-35) peptide in CA1 pyramidal neurons of neonatal rat hippocampal slice.
Overload of intracellular calcium caused by amyloid-beta peptide has been implicated in the pathogenesis of neuronal damage in Alzheimer's disease. Voltage-gated calcium channels (VGCCs) provide one of the major sources of Ca(2+) entry into cells. Here, we investigated whether icariin had effect on the changes of calcium currents induced by Abeta(25-35) in hippocampal pyramidal neurons. Using whole-cell patch-clamp, we showed that Abeta(25-35) enhanced the inward Ba(2+) and Ca(2+) currents. The currents were partially inhibited by Ni(2+) and completely suppressed by Cd(2+), indicating that Abeta(25-35) disrupts intracellular calcium homeostasis via the modulation of both L- and T-type channels. Furthermore, icariin nearly complete suppressed the abnormal inward calcium currents induced by Abeta(25-35) in a dose-dependant manner. Our findings suggest that the potential neuroprotective effect of icariin on Abeta(25-35)-induced neurotoxicity via the balance intracelluar calcium homeostasis.
Li
Li
L
Department of Integrated Chinese and Western Medicine, First Hospital, Peking University, Beijing, China.
Tsai
Hao-Jan
HJ
Li
Lin
L
Wang
Xue-Mei
XM
D000544:Alzheimer Disease / Q000517:prevention & control; D016229:Amyloid beta-Peptides / Q000378:metabolism*; D000818:Animals; D000831:Animals, Newborn; D001464:Barium / Q000378:metabolism; D002104:Cadmium / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels / Q000187:drug effects*; D020746:Calcium Channels, L-Type / Q000187:drug effects; D020747:Calcium Channels, T-Type / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D034181:Epimedium / Q000737:chemistry; D005419:Flavonoids / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D006706:Homeostasis; D007473:Ion Channels / Q000187:drug effects; D009474:Neurons; D018696:Neuroprotective Agents / Q000494:pharmacology*; D009532:Nickel / Q000494:pharmacology; D018408:Patch-Clamp Techniques; D010936:Plant Extracts / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley
D016229:Amyloid beta-Peptides; D015220:Calcium Channels; D020746:Calcium Channels, L-Type; D020747:Calcium Channels, T-Type; D005419:Flavonoids; D007473:Ion Channels; D018696:Neuroprotective Agents; D010936:Plant Extracts; D002104:Cadmium; D001464:Barium; D009532:Nickel; D002118:Calcium; C056599:icariin