Genetic cathepsin B deficiency reduces beta-amyloid in transgenic mice expressing human wild-type amyloid precursor protein.
Neurotoxic beta-amyloid (Abeta) peptides participate in Alzheimer's disease (AD); therefore, reduction of Abeta generated from APP may provide a therapeutic approach for AD. Gene knockout studies in transgenic mice producing human Abeta may identify targets for reducing Abeta. This study shows that knockout of the cathepsin B gene in mice expressing human wild-type APP (hAPPwt) results in substantial decreases in brain Abeta40 and Abeta42 by 67% and decreases in levels of the C-terminal beta-secretase fragment (CTFbeta) derived from APP. In contrast, knockout of cathepsin B in mice expressing hAPP with the rare Swedish (Swe) and Indiana (Ind) mutations had no effect on Abeta. The difference in reduction of Abeta in hAPPwt mice, but not in hAPPSwe/Ind mice, shows that the transgenic model can affect cathepsin B gene knockout results. Since most AD patients express hAPPwt, these data validate cathepsin B as a target for development of inhibitors to lower Abeta in AD.
Hook
Vivian Y H
VY
Depts of Neurosciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093-0744, USA. vhook@ucsd.edu
Kindy
Mark
M
Reinheckel
Thomas
T
Peters
Christoph
C
Hook
Gregory
G
D000544:Alzheimer Disease / Q000378:metabolism* / Q000628:therapy; D016229:Amyloid beta-Peptides / Q000378:metabolism*; D016564:Amyloid beta-Protein Precursor / Q000235:genetics; D000818:Animals; D001921:Brain / Q000378:metabolism*; D002401:Cathepsin B / Q000172:deficiency* / Q000235:genetics; D055786:Gene Knockout Techniques; D006801:Humans; D051379:Mice; D008822:Mice, Transgenic; D009154:Mutation; D010446:Peptide Fragments / Q000378:metabolism*
D016229:Amyloid beta-Peptides; D016564:Amyloid beta-Protein Precursor; D010446:Peptide Fragments; C075222:amyloid beta-protein (1-42); D002401:Cathepsin B