Early postprandial low-grade inflammation after high-fat meal in healthy rats: possible involvement of visceral adipose tissue.
In the postprandial period, low-grade inflammation may contribute to vascular endothelial dysfunction, a hallmark of atherogenesis. Little is known about the involvement of the adipose tissue in the initiation of the postprandial inflammatory response such as obtained after a high-saturated fat meal (HFM). In the present study, we first studied the time course of appearance of systemic inflammation after a HFM in healthy rats, and then we investigated whether a HFM activates the inflammatory signaling in the visceral adipose tissue, with a focus on the key component, nuclear factor-kappaB (NF-kappaB). Two hours after the HFM, plasma IL-6 and PAI-1, but not plasma C-reactive protein and soluble intracellular adhesion molecule-1, showed a marked, transient increase. These changes were specific to the postprandial state as not observed after a control water load. Neutrophils count and activation markers CD11B and CD62L, assessed by flow cytometry, also rose significantly 2 h after the HFM, while remaining steady after the control. At the same time, the HFM decreased significantly B-cell count and expression of the activation marker CD62L. Interestingly, at the same early time after the HFM, in the visceral adipose tissue, there was a 2.2-fold increase in the activation of NF-kappaB (p65) in nuclear extract and an increase in IL-6 mRNA. As far as we know, this is the first study evidencing an acute, postprandial activation of inflammation in visceral adipose tissue. This early activation of NF-kappaB pathway after a HFM may play a triggering role in the initiation of the complex postprandial proatherogenic phenotype.
UMR914 Nutrition Physiology and Ingestive Behavior, INRA, CRNH-IdF, F-75005 Paris, France.
Joëlle
J
Magné
François
F
Mariotti
Romy
R
Fischer
Véronique
V
Mathé
Daniel
D
Tomé
Jean François
JF
Huneau
D000273:Adipose Tissue; D000818:Animals; D050197:Atherosclerosis; D039481:CD11b Antigen / Q000096:biosynthesis; D002467:Cell Nucleus / Q000378:metabolism; D004041:Dietary Fats; D004195:Disease Models, Animal; D007249:Inflammation; D015850:Interleukin-6 / Q000378:metabolism; D050152:Intra-Abdominal Fat / Q000378:metabolism*; D019041:L-Selectin / Q000096:biosynthesis; D008297:Male; D016328:NF-kappa B / Q000378:metabolism; D010641:Phenotype; D019518:Postprandial Period; D051381:Rats; D011921:Rats, Inbred WKY
D039481:CD11b Antigen; D004041:Dietary Fats; D015850:Interleukin-6; D016328:NF-kappa B; D019041:L-Selectin