The effects of ginsenosides to amyloid fibril formation by RCMκ-casein.
When not incorporated into the casein micelle, isolated κ-casein spontaneously forms amyloid fibrils under physiological conditions, and is a convenient model for researching generic aspects of fibril formation. Ginsenosides have recently attracted much research interest because of the effects on aging diseases, which are always associated with amyloid fibril formation, for example, Alzheimer's, Parkinson's, and Huntington's diseases. In addition, the mechanism remains unclear that ginsenosides exert the effects against aging diseases. To address these aspects, we have investigated the ability of ginsenoside Rb1, Rc, Rg1, and Re influencing fibril formation by RCMκ-casein (reduced and carboxymethylated κ-casein), with the methods of Thioflavin T fluorescence assay, transmission electron microscopy (TEM), and intrinsic fluorescence spectroscopy. The results showed that ginsenoside Rb1 and Rg1 inhibited obviously RCMκ-CN fibrillation in both the initial rate and final level of ThT fluorescence. On the contrary, ginsenoside Re had a few effect on promoting RCMκ-CN fibril formation, proved by thick and larger fibrils observed frequently in TEM. While Rc did not influence RCMκ-CN fibrillation. It is demonstrated that Rg1 prevent RCMκ-CN fibril formation by stabilising RCMκ-CN in its native like state. Additional chemical structure difference of ginsenosides and the effects on fibril formation are also implicated.
Pharmacy College, Jilin University, 1266# Fujin Road, Changchun, Jilin Province 130021, China.
Jihua
J
Liu
Pharmacy College, Jilin University, 1266# Fujin Road, Changchun, Jilin Province 130021, China.
Fanbo
F
Chen
Pharmacy College, Jilin University, 1266# Fujin Road, Changchun, Jilin Province 130021, China.
Jianyuan
J
Yin
Pharmacy College, Jilin University, 1266# Fujin Road, Changchun, Jilin Province 130021, China.
Fengquan
F
Bu
Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China.
Baohua
B
Zheng
Pharmacy College, Jilin University, 1266# Fujin Road, Changchun, Jilin Province 130021, China.
Miao
M
Yang
Pharmacy College, Jilin University, 1266# Fujin Road, Changchun, Jilin Province 130021, China.
Yunhua
Y
Wang
Pharmacy College, Jilin University, 1266# Fujin Road, Changchun, Jilin Province 130021, China.
Dandan
D
Sun
Pharmacy College, Jilin University, 1266# Fujin Road, Changchun, Jilin Province 130021, China. Electronic address: mengqin@jlu.edu.cn.
Qin
Q
Meng
D000682:Amyloid / Q000037:antagonists & inhibitors* / Q000737:chemistry; D052160:Benzothiazoles; D002364:Caseins / Q000737:chemistry*; D036145:Ginsenosides / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D008956:Models, Chemical; D055550:Protein Stability; D012996:Solutions; D013050:Spectrometry, Fluorescence; D013329:Structure-Activity Relationship; D013844:Thiazoles
D000682:Amyloid; D052160:Benzothiazoles; D002364:Caseins; D036145:Ginsenosides; D012996:Solutions; D013844:Thiazoles; C044462:ginsenoside Rc; C009462:thioflavin T; C049864:ginsenoside Re; C442759:ginsenoside Rb1; C035054:ginsenoside Rg1
Amyloid fibrils; Ginsenosides; TEM; ThT assay; κ-Casein