Article

Lipogenesis in arterial wall and vascular smooth muscle cells of Psammomys obesus: its regulation and abnormalities in diabetes.

ERI22-EA4173, faculté Rockefeller, UCB Lyon 1, 8, avenue Rockfeller, 69008 Lyon, France.
Diabetes & Metabolism (impact factor: 2.41). 03/2010; 36(3):221-8. DOI:10.1016/j.diabet.2010.01.003
Source: PubMed

ABSTRACT Lipogenesis is expressed in vascular smooth muscle cells (VSMCs), and such in situ lipogenesis could be providing the fatty acids for triglyceride synthesis and cholesterol esterification, and contributing to lipid accumulation in the arterial wall. This study investigated both the expression and regulation of lipogenesis in VSMCs to determine if they are modified in Psammomys obesus gerbils fed a high-fat diet as a model of insulin resistance and diabetes.
Aortas were collected from diabetic and non-diabetic P. obesus for histological examination, measurement of lipogenic gene expression and VSMC culture.
The aortas of diabetic animals exhibited lipid deposits and foam cells as well as disorganization of elastic fibres. However, lipogenic gene expression was not modified. VSMCs in vitro from the aortas of diabetic animals had, compared with cells from non-diabetic animals, lower mRNA levels of SREBP-1c and ChREBP. An adipogenic medium stimulated moderate FAS and ACC1 expression in cells from both diabetic and non-diabetic animals, but glucose and insulin on their own had no such stimulatory action. Also, triiodothyronine (T3) had a clear stimulatory action, while angiotensin II had a moderate effect, in cells from non-diabetic P. obesus, but not from diabetic animals, whereas LXR agonists stimulated lipogenesis in cells from both animal groups.
Lipogenesis is expressed in the arterial walls and VSMCs of P. obesus. However, its expression was not increased in diabetes, and did not respond to either T3 or angiotensin II. Therefore, lipogenesis in situ is unlikely to contribute to the accumulation of lipids in the arterial walls of diabetic P. obesus gerbils.

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Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

ACC1 expression
 
arterial wall
 
cholesterol esterification
 
clear stimulatory action
 
diabetic animals
 
diabetic animals exhibited lipid deposits
 
fatty acids
 
high-fat diet
 
histological examination
 
lipid accumulation
 
lipogenic gene expression
 
LXR agonists
 
moderate effect
 
non-diabetic animals
 
non-diabetic P. obesus
 
P. obesus
 
Psammomys obesus gerbils
 
situ lipogenesis
 
stimulatory action
 
VSMC culture