open access

https://hdl.handle.net/2115/82141

Activation of Invariant Natural Killer T Cells by alpha-Galactosylceramide Attenuates the Development of Angiotensin II-Mediated Abdominal Aortic Aneurysm in Obese ob/ob Mice

英語

alpha-galactosylceramide

2021-05-10

Frontiers Media

Frontiers in Cardiovascular Medicine

8

659418

The infiltration and activation of macrophages as well as lymphocytes within the aorta contribute to the pathogenesis of abdominal aortic aneurysm (AAA). Invariant natural killer T (iNKT) cells are unique subset of T lymphocytes and have a crucial role in atherogenesis. However, it remains unclear whether iNKT cells also impact on the development of AAA. Ob/ob mice were administered angiotensin II (AngII, 1,000 ng/kg/min) or phosphate-buffered saline (PBS) by osmotic minipumps for 4 weeks and further divided into 2 groups; alpha-galactosylceramide (alpha GC; PBS-alpha GC; n = 5 and AngII-alpha GC; n = 12), which specifically activates iNKT cells, and PBS (PBS-PBS; n = 10, and AngII-PBS; n = 6). Maximal abdominal aortic diameter was comparable between PBS-PBS and PBS-alpha GC, and was significantly greater in AngII-PBS than in PBS-PBS. This increase was significantly attenuated in AngII-alpha GC without affecting blood pressure. alpha GC significantly enhanced iNKT cell infiltration compared to PBS-PBS. The ratio of F4/80-positive macrophages or CD3-positive T lymphocytes area to the lesion area was significantly higher in AngII-PBS than in PBS-PBS, and was significantly decreased in AngII-alpha GC. Gene expression of M2-macrophage specific markers, arginase-1 and resistin-like molecule alpha, was significantly greater in aortic tissues from AngII-alpha GC compared to AngII-PBS 1 week after AngII administration, and this increase was diminished at 4 weeks. Activation of iNKT cells by alpha GC can attenuate AngII-mediated AAA in ob/ob mice via inducing anti-inflammatory M2 polarized state. Activation of iNKT cells by the bioactive lipid alpha GC may be a novel therapeutic target against the development of AAA.

学術雑誌論文

Version of Record

2297-055X