title: Natural Tripeptide-Based Inhibitor of Multifaceted Amyloid β Toxicity.
abstract: Accumulation of amyloid beta (Aβ) peptide and its aggregates in the human brain is considered as one of the hallmarks of Alzheimer's disease (AD). The polymorphic oligomers and fully grown fibrillar aggregates of Aβ exhibit different levels of neuronal toxicity. Moreover, aggregation of Aβ in the presence of redox-active metal ions like Cu(2+) is responsible for the additional trait of cellular toxicity induced by the generation of reactive oxygen species (ROS). Herein, a multifunctional peptidomimetic inhibitor (P6) has been presented, based on a naturally occurring metal chelating tripeptide (GHK) and the inhibitor of Aβ aggregation. It was shown by employing various biophysical studies that P6 interact with Aβ and prevent the formation of toxic Aβ forms like oligomeric species and fibrillar aggregates. Further, P6 successfully sequestered Cu(2+) from the Aβ-Cu(2+) complex and maintained it in a redox-dormant state to prevent the generation of ROS. P6 inhibited membrane disruption by Aβ oligomers and efficiently prevented DNA damage caused by the Aβ-Cu(2+) complex. PC12 cells were rescued from multifaceted Aβ toxicity when treated with P6, and the amount of ROS generated in cells was reduced. These attributes make P6 a potential therapeutic candidate to ameliorate the multifaceted Aβ toxicity in AD.
authors.affiliation: Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur P. O., Bengaluru 560064, Karnataka, India.
authors.forename: K
authors.initials: K
authors.lastname: Rajasekhar
authors.affiliation: Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur P. O., Bengaluru 560064, Karnataka, India.
authors.forename: Chilakapati
authors.initials: C
authors.lastname: Madhu
authors.affiliation: Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur P. O., Bengaluru 560064, Karnataka, India.
authors.forename: T
authors.initials: T
authors.lastname: Govindaraju
mesh_terms: D016229:Amyloid beta-Peptides / Q000378:metabolism* / Q000494:pharmacology / Q000633:toxicity*; D000704:Analysis of Variance; D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D002942:Circular Dichroism; D003300:Copper / Q000633:toxicity*; D004249:DNA Damage / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006801:Humans; D009842:Oligopeptides / Q000494:pharmacology; D016716:PC12 Cells / Q000187:drug effects*; D010446:Peptide Fragments / Q000494:pharmacology; D057786:Peptidomimetics / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000378:metabolism; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D013050:Spectrometry, Fluorescence
chemical_list: D016229:Amyloid beta-Peptides; D009842:Oligopeptides; D010446:Peptide Fragments; D057786:Peptidomimetics; D017382:Reactive Oxygen Species; C474023:iAbeta5 peptide; C020905:glycyl-histidyl-lysine; D003300:Copper
keywords: Alzheimer’s disease; DNA damage; amyloid beta; membrane disruption; multifunctional inhibitor; oxidative stress