1. |
|
|
2. |
|
|
3. |
|
|
4. |
|
|
5. |
|
|
6. |
|
|
7. |
|
|
8. |
|
|
9. |
|
|
10. |
|
|
11. |
|
|
12. |
|
|
13. |
|
|
14. |
- Galman, C, et al.
(författare)
-
Age-induced hypercholesterolemia in the rat relates to reduced elimination but not increased intestinal absorption of cholesterol
- 2007
-
Ingår i: American journal of physiology. Endocrinology and metabolism. - : American Physiological Society. - 0193-1849 .- 1522-1555. ; 293:3, s. E737-E742
-
Tidskriftsartikel (refereegranskat)abstract
- Plasma cholesterol increases in normal aging in both rodents and humans. This is associated with reduced elimination of cholesterol as bile acids (BAs) and decreased receptor-mediated clearance of plasma LDL, changes that can be reversed by treatment with growth hormone (GH). The level of intestinal absorption of cholesterol may also contribute to the development of hypercholesterolemia. In this study, we investigated whether cholesterol absorption increases with age and whether any such age-related change could be influenced by treatment with GH or ezetimibe (EZE). Male rats aged 6 and 18 mo were studied with and without GH or EZE treatment. BA synthesis was reduced and plasma cholesterol was increased in the old animals, whereas cholesterol absorption was unaltered. Cholesterol absorption was not altered by GH treatment but was reduced by EZE in both groups of animals. Hepatic LDL receptors (LDLRs), scavenger receptor class B type 1, and proprotein convertase subtilisin/kexin type 9 serine protease (PCSK9) transcripts were unchanged in old animals. GH treatment induced LDLRs, PCSK9 transcripts, and BA synthesis. We conclude that the age-induced hypercholesterolemia in the rat and its reversal by GH treatment relates to altered degradation of cholesterol in the liver and is not due to changes in cholesterol absorption.
|
|
15. |
|
|
16. |
|
|
17. |
|
|
18. |
|
|
19. |
|
|
20. |
|
|
21. |
|
|
22. |
|
|
23. |
- Klingenberg, Roland, et al.
(författare)
-
Depletion of FOXP3(+) regulatory T cells promotes hypercholesterolemia and atherosclerosis
- 2013
-
Ingår i: Journal of Clinical Investigation. - 0021-9738 .- 1558-8238. ; 123:3, s. 1323-1334
-
Tidskriftsartikel (refereegranskat)abstract
- Atherosclerosis is a chronic inflammatory disease promoted by hyperlipidemia. Several studies support FOXP3-positive regulatory T cells (Tregs) as inhibitors of atherosclerosis; however, the mechanism underlying this protection remains elusive. To define the role of FOXP3-expressing Tregs in atherosclerosis, we used the DEREG mouse, which expresses the diphtheria toxin (DT) receptor under control of the Treg-specific Foxp3 promoter, allowing for specific ablation of FOXP3(+) Tregs. Lethally irradiated, atherosclerosis-prone, low-density lipoprotein receptor-deficient (Ldlr(-/-)) mice received DEREG bone marrow and were injected with DT to eliminate FOXP3(+) Tregs. Depletion of Tregs caused a 2.1-fold increase in atherosclerosis without a concomitant increase in vascular inflammation. These mice also exhibited a 1.7-fold increase in plasma cholesterol and an atherogenic lipoprotein profile with increased levels of VLDL. Clearance of VLDL and chylomicron remnants was hampered, leading to accumulation of cholesterol-rich particles in the circulation. Functional and protein analyses complemented by gene expression array identified reduced protein expression of sortilin-1 in liver and increased plasma enzyme activity of lipoprotein lipase, hepatic lipase, and phospholipid transfer protein as mediators of the altered lipid phenotype. These results demonstrate that FOXP3(+) Tregs inhibit atherosclerosis by modulating lipoprotein metabolism.
|
|
24. |
|
|
25. |
|
|