title: A-type dimeric epigallocatechin-3-gallate (EGCG) is a more potent inhibitor against the formation of insulin amyloid fibril than EGCG monomer.
abstract: Because fibrillary protein aggregates is regarded to be closely associated with many diseases such as Alzheimer's disease, diabetes, and Parkinson's disease, growing interest and researches have been focused on finding potential fibrillation inhibitors. In the present study, the inhibitory effects of epigallocatechin-3-gallate (EGCG) and A-type dimeric epigallocatechin-3-gallate (A-type EGCG dimer) on the formation of insulin fibrillation were compared by multi-dimensional approaches including thioflavin-T (ThT) fluorescence assay, 1-anilinonaphthalene-8-sulfonic (ANS) fluorescence assay, dynamic light scattering (DLS), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy and circular dichroism (CD) spectroscopy. Our results confirmed that A-type EGCG dimer is a more potent inhibitor against the formation of bovine insulin amyloid fibril than EGCG. In addition, A-type EGCG dimer could not only inhibit insulin amyloid fibril formation, but also change the aggregation pathway and induce bovine insulin into amorphous aggregates. The results of the present study may provide a new guide on finding novel anti-amyloidogenic agents.
authors.affiliation: College of Food Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Rong-Zu
authors.initials: RZ
authors.lastname: Nie
authors.affiliation: College of Food Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhu
authors.affiliation: College of Food Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Jin-Ming
authors.initials: JM
authors.lastname: Peng
authors.affiliation: College of Food Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Zhen-Zhen
authors.initials: ZZ
authors.lastname: Ge
authors.affiliation: College of Food Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China; Key Laboratory of Environment Correlative Food Science, Huazhong Agricultural University, Ministry of Education, Wuhan, 430070, China. Electronic address: lichmyl@126.com.
authors.forename: Chun-Mei
authors.initials: CM
authors.lastname: Li
mesh_terms: D000682:Amyloid / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology; D002417:Cattle; D007328:Insulin / Q000737:chemistry / Q000378:metabolism*; D066263:Protein Aggregation, Pathological / Q000188:drug therapy / Q000378:metabolism*
chemical_list: D000682:Amyloid; D007328:Insulin; D002392:Catechin; C045651:epigallocatechin gallate
keywords: A-type EGCG dimer; Amyloid; EGCG; Fibril; Inhibition