Journal: Journal of Alzheimer's Disease

Article Title: Leptin Reduces the Accumulation of Aβ and Phosphorylated Tau Induced by 27-Hydroxycholesterol in Rabbit Organotypic Slices

doi: 10.3233/jad-2010-1298

Figure Lengend Snippet: Fig. 5. Treatment with 27-OHC increases levels of phosphorylated tau in organotypic slices, as detected by PHF-1 antibody (a and b) and reduces levels of inactive phosphorylated Ser9 GSK-3β (c and d), potentially increasing tau phosphorylation. Leptin reverses the 27-OHC induced increase in tau phosphorylation by increasing the levels of Ser9 GSK-3β (a-d). *p < 0.05, **p < 0.01 versus control and †p < 0.05 versus 27-OHC treatment. 15 sections from each of 4 rabbits were used for each treatment.

Article Snippet: Proteins (10 μg) were separated in SDS-PAGE gels followed by transfer to a polyvinylidene difluoride membrane (BioRad, Hercules, CA) and incubation with the following monoclonal antibodies: anti-AβPP mouse antibody (1:100; Millipore, Bedford, MA), anti- BACE-1 rabbit antibody (1:100; Millipore, Bedford, MA), antiGSK-3β mouse antibody (1:100; BD Biosciences, San Jose, CA), anti-IDE rabbit antibody (1:100; Chemicon International, Temecula, CA), anti-leptin rabbit antibody (1:1000; ABR Affinity Bioreagents, Rockford, IL), anti-LRP-1 mouse antibody (1:100; Biodesign International, Saco, ME), anti-p-GSK3β Ser9 rab- bit antibody (1:100; Cell Signaling, Boston, MA), anti-PHF-1 and CP13 mouse antibodies (1:500; gift from Dr. Peter Davis, Albert Einstein College of Medicine), anti-sAβPPα mouse antibody (1:100; IBL, Minneapolis, MN), and anti-Tau5 mouse antibody (1:200; Calbiochem, San Diego, CA). β-actin was used as a gel loading control.

Techniques: Phospho-proteomics, Control

Journal: Journal of Alzheimer's Disease

Article Title: Leptin Reduces the Accumulation of Aβ and Phosphorylated Tau Induced by 27-Hydroxycholesterol in Rabbit Organotypic Slices

doi: 10.3233/jad-2010-1298

Figure Lengend Snippet: Fig. 6. High cholesterol diets lead to increased levels of plasma cholesterol (hypercholesterolemia). Hypercholesterolemia reduces transport of leptin from the circulation into the brain and increases plasma levels of the cholesterol metabolite 27-OHC, thus allowing excess entry of 27-OHC into the brain and reduction of leptin expression in this organ. Low levels of leptin in the hippocampus trigger Aβ production by increasing AβPP levels, fostering AβPP processing by BACE-1, and reducing AβPP processing by the non-amyloidogenic α pathway. Increased levels of 27-OHC and reduced leptin expression in the brain also decrease the degradation and clearance of Aβ by reducing levels of IDE and LRP-1 respectively, thereby leading to the accumulation of this peptide. 27-OHC also increases the phosphorylation of tau (p-tau) by increasing the activity of GSK-3β. (+), increased; (−), decreased.

Article Snippet: Proteins (10 μg) were separated in SDS-PAGE gels followed by transfer to a polyvinylidene difluoride membrane (BioRad, Hercules, CA) and incubation with the following monoclonal antibodies: anti-AβPP mouse antibody (1:100; Millipore, Bedford, MA), anti- BACE-1 rabbit antibody (1:100; Millipore, Bedford, MA), antiGSK-3β mouse antibody (1:100; BD Biosciences, San Jose, CA), anti-IDE rabbit antibody (1:100; Chemicon International, Temecula, CA), anti-leptin rabbit antibody (1:1000; ABR Affinity Bioreagents, Rockford, IL), anti-LRP-1 mouse antibody (1:100; Biodesign International, Saco, ME), anti-p-GSK3β Ser9 rab- bit antibody (1:100; Cell Signaling, Boston, MA), anti-PHF-1 and CP13 mouse antibodies (1:500; gift from Dr. Peter Davis, Albert Einstein College of Medicine), anti-sAβPPα mouse antibody (1:100; IBL, Minneapolis, MN), and anti-Tau5 mouse antibody (1:200; Calbiochem, San Diego, CA). β-actin was used as a gel loading control.

Techniques: Clinical Proteomics, Expressing, Phospho-proteomics, Activity Assay