Abstract
BackgroundAmyloid-β is recognized as the major constituent of senile plaque found in subjects with Alzheimer's disease. However, there is increasing evidence that in a physiological context amyloid-β may serve as regulating apolipoprotein, primarily of the triglyceride enriched lipoproteins. To consider this hypothesis further, this study utilized an in vivo immunological approach to explore in lipogenic tissue whether amyloid-β colocalizes with nascent triglyceride-rich lipoproteins.ResultsIn murine absorptive epithelial cells of the small intestine, amyloid-β had remarkable colocalization with chylomicrons (Manders overlap coefficient = 0.73 ± 0.03 (SEM)), the latter identified as immunoreactive apolipoprotein B. A diet enriched in saturated fats doubled the abundance of both amyloid-β and apo B and increased the overlap coefficient of the two proteins (0.87 ± 0.02). However, there was no evidence that abundance of the two proteins was interdependent within the enterocytes (Pearson's Coefficient < 0.02 ± 0.03), or in plasma (Pearson's Coefficient < 0.01).ConclusionThe findings of this study are consistent with the possibility that amyloid-β is secreted by enterocytes as an apolipoprotein component of chylomicrons. However, secretion of amyloid-β appears to be independent of chylomicron biogenesis.
Highlights
Amyloid- is recognized as the major constituent of senile plaque found in subjects with Alzheimer's disease
Western blotting for plasma apolipoprotein B Plasma samples were separated on NuPAGE 3-8% Trisacetate gels (EA03752BOX, Invitrogen, Victoria, Australia) at 150 V (Biorad Model 20012.0) for 1 hr
The membranes were incubated with polyclonal rabbit anti-human apolipoprotein B (apo B) 1:100 (Q0497, Dakocytomation, Glostrup, Denmark), and with donkey anti-rabbit immunoglobulin G (IgG) horseradish peroxidase (HRP) (Na934V, Amersham Bioscience, Buckinghamshire, UK)
Summary
Amyloid- is recognized as the major constituent of senile plaque found in subjects with Alzheimer's disease. There is increasing evidence that in a physiological context amyloid- may serve as regulating apolipoprotein, primarily of the triglyceride enriched lipoproteins. To consider this hypothesis further, this study utilized an in vivo immunological approach to explore in lipogenic tissue whether amyloid- colocalizes with nascent triglyceriderich lipoproteins. Amyloid- is recognized as the principal protein in senile plaques in subjects with Alzheimer's disease (AD) [1]. Several lines of evidence suggest that one physiological role for amyloid- is as a regulating apolipoprotein, of the triglyceride-rich lipoproteins (TRL's). Ingestion of a lipid rich meal causes a transient increase in plasma of soluble APP, concomitant with postprandial lipaemia [9] and when injected intravenously associated with TRL-emulsions, amyloid- increased uptake in fat-rich tissues relative to liver [10]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
