A catalytic reaction of H2O2 production by an amyloid beta-peptide (Abeta)-Cu complex with cholesterol incorporated in a liposome was kinetically analyzed. The Michaelis-Menten model was applied to the H2O2 production reaction using cholesterol as the substrate catalyzed by the Abeta-Cu complex. The Km value for the Abeta-Cu complex catalytic reaction with cholesterol-containing 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) liposomes (Km=0.436 microM for Abeta(1-40); Km=0.641 microM for Abeta(1-42)) was found to be smaller than that with cholesterol-containing 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) liposomes (Km=0.585 microM for Abeta(1-40), Km=0.890 microM for Abeta(1-42)). The results imply that membrane properties could play an important role in the interactions of the Abeta-Cu complex with cholesterol in these liposomes. Considering the physical states of the cholesterol/POPC (liquid disordered phase) and cholesterol/DPPC (liquid ordered phase) liposomes in the present reaction conditions, the data obtained suggests that the H2O2-generating activity of the Abeta-Cu complex, accompanied by oxidation of membrane-incorporated cholesterol, could be effected by the phase of the liposome membranes.
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http://dx.doi.org/10.1263/jbb.100.455 | DOI Listing |
Int J Biol Macromol
December 2024
Department of Chemistry, School of Chemistry and Chemical Engineering, Northwestern Polytechnical University, 127 Youyi Road, Xi'an 710072, China. Electronic address:
Bioorg Chem
January 2025
Henan Province Key Laboratory of New Opto-electronic Functional Materials, Anyang Normal University, Anyang, Henan 455000, China. Electronic address:
β-Amyloid (Aβ) peptides are believed as the diagnostic biomarkers and therapeutic targets of Alzheimer's disease (AD). Their complexes with copper ions can catalyze the generation of reactive oxygen species (ROS) to further promote neuronal death. Herein, we suggested that porphyrin-substituted phenylalanine-phenylalanine nanoparticles (TPP-FF NPs) could inhibit the aggregation of Aβ monomers, disassemble the fibrillar Aβ aggregates under light illumination, and depressing the Cu-induced generation of ROS.
View Article and Find Full Text PDFNeurology
July 2024
From the The Australian e-Health Research Centre (Y.X., V.D., J.F., P.B.), CSIRO Health and Biosecurity, Brisbane; Department of Nuclear Medicine and Centre for PET (V.D., C.R.), Austin Health, Melbourne; Centre for Precision Health (S.M.L.), Edith Cowan University; Collaborative Genomics and Translation Group (S.M.L.), School of Medical and Health Sciences, Edith Cowan University, Joondalup; Curtin Medical School (S.M.L.), Curtin University, Bentley; The Florey Institute of Neuroscience and Mental Health (C.J.F., C.R., C.L.M., P.M.), The University of Melbourne; Centre for Healthy Ageing (S.R.R.-S.), Health Futures Institute, Murdoch University; Australian Alzheimer's Research Foundation (S.R.R.-S., R.N.M.), Sarich Neuroscience Research Institute, Nedlands; School of Psychological Science (S.R.R.-S.), University of Western Australia, Crawley; School of Medical and Health Sciences (S.R.R.-S., R.N.M.), Edith Cowan University, Joondalup; Department of Biomedical Sciences (R.N.M.), Macquarie University, Sydney; Queensland Brain Institute (E.J.C.), and School of Biomedical Sciences (E.J.C.), The University of Queensland, Brisbane; and Cogstate Ltd. (P.M.), Melbourne, Australia.
ACS Chem Neurosci
July 2024
Organic and Medicinal Chemistry and Structural Biology and Bioinformatics Division, CSIR─Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, WB, India.
ACS Chem Neurosci
February 2023
Organic and Medicinal Chemistry and Structural Biology and Bioinformatics Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Jadavpur, Kolkata 700 032, WB, India.
The misfolding of amyloid beta (Aβ) peptides into Aβ fibrillary aggregates is a major hallmark of Alzheimer's disease (AD), which responsible for the excess production of hydrogen peroxide (HO), a prominent reactive oxygen species (ROS) from the molecular oxygen (O) by the reduction of the Aβ-Cu(I) complex. The excessive production of HO causes oxidative stress and inflammation in the AD brain. Here, we have designed and developed a dual functionalized molecule VBD by using π-conjugation (C═C) in the backbone structure.
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