Salvianolic acid B inhibits fibril formation and neurotoxicity of amyloid beta-protein in vitro.
OBJECTIVE
To observe the effect of salvianolic acid-B (SalB) on amyloid beta-protein (A-beta) fibril formation and its toxicity towards PC12 cells.


METHODS
A-beta (1 - 40) was incubated with or without SalB at 25 degrees C for 30 h, 48 h, and 100 h. Fibril formation was then viewed under an electron microscope. Toxicity of the A-beta (1 - 40) towards PC12 cells was measured with 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT). A-beta (25 - 35) was aged by incubating at 25 degrees C for 7 d, then the peptide was incubated with PC12 cells with or without SalB. Toxicity of A-beta (25-35) towards PC12 cells was observed with MTT.


RESULTS
Following incubation at 25 degrees C for 30 h, A-beta (1 - 40) (100 mg/L) aggregated and formed fibrils. SalB 10-100 nmol/L completely prevented the fibril formation within 30 h. Extension of amyloid fibrils increased with prolonging the incubation time. SalB inhibited the fibril formation process during this period. In the MTT assay A-beta (1 - 40) incubated with SalB manifested significantly lower toxicity to PC12 cells compared with that without SalB. Besides, SalB 1 micromol/L significantly attenuated the toxicity of aged A-beta (25 - 35) to PC12 cells.


CONCLUSIONS
SalB could inhibit A-beta aggregation and fibril formation, as well as directly inhibit the cellular toxicity of aged A-beta towards PC12 cells.
Tang
M K
MK
Institute of Materia Medica, Chinese Academy of Medical Sciences, Beijing 100050, China. zjtian@public.bta.net.cn
Zhang
J T
JT
D016229:Amyloid beta-Peptides / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D001572:Benzofurans / Q000494:pharmacology*; D018929:Cell Culture Techniques; D002455:Cell Division / Q000187:drug effects; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D016716:PC12 Cells; D051381:Rats; D053630:Depsides
D016229:Amyloid beta-Peptides; D000975:Antioxidants; D001572:Benzofurans; D004365:Drugs, Chinese Herbal; C076944:salvianolic acid B; D053630:Depsides