Bone marrow angiotensin AT2 receptor deficiency aggravates atherosclerosis development by eliminating macrophage liver X receptor-mediated anti-atherogenic actions.

Background: Bone marrow (BM) Angiotensin II (Ang II) type 1 (AT1) receptor plays a crucial role in atherosclerosis development; however, the effect of BM Ang II type 2 (AT2) receptor on atherogenesis remains undefined.

Methods And Results: We generated BM chimera apoE-deficient (apoE(-/-)) mice whose BM cells were repopulated with AT2-deficient (Agtr2(-/-)) or wild-type (Agtr2(+/+)) cells. After 2 months of a high-cholesterol diet, the atherosclerotic lesion area was significantly increased in the apoE(-/-)/BM-Agtr2(-/-) mice compared with the apoE(-/-)/BM-Agtr2(+/+) mice (51%, P < 0.

Transplantation of periaortic adipose tissue from angiotensin receptor blocker-treated mice markedly ameliorates atherosclerosis development in apoE-/- mice.

Background: Perivascular adipose tissue is implicated in vasoreactivity; however, its effect on atherosclerosis remains undefined.

Methods And Results: We examined the effect of a high-cholesterol diet (HCD) on phenotypic alterations of the thoracic periaortic adipose tissue (tPAT) in apoE-deficient (apoE(-/-)) mice. Gene expression of the components of the renin angiotensin system and that of macrophage markers were significantly higher in apoE(-/-) mice fed an HCD than in those fed a chow diet (CD).

Periaortic adipose tissue-specific activation of the renin-angiotensin system contributes to atherosclerosis development in uninephrectomized apoE-/- mice.

Chronic kidney disease (CKD) is an independent risk factor for the development of cardiovascular disease. The perivascular adipose tissue is closely implicated in the development of atherosclerosis; however, the contribution to CKD-associated atherogenesis remains undefined. Eight-week-old apoE-deficient mice were uninephrectomized and fed a high-cholesterol diet starting at 12 wk of age.

Vascular angiotensin II type 2 receptor attenuates atherosclerosis via a kinin/NO-dependent mechanism.

Introduction: The angiotensin II (Ang II) type 1 receptor exerts pro-atherogenic action by augmenting oxidative stress, whereas the Ang II type 2 receptor (AT2)-mediated effect on atherosclerosis remains controversial.

Materials And Methods: AT2 transgenic (AT2-Tg) mice, which overexpress AT2 in their vascular smooth muscle cells, were crossed with apoE-deficient (apoE(-/-)) mice to generate AT2 transgenic apoE(-/-) mice (AT2-Tg/apoE(-/-)).

Results: A subpressor dose of Ang II infusion exaggerated atherosclerosis development in apoE(-/-) mice, which was markedly suppressed in AT2-Tg/apoE(-/-) mice.

Bone marrow AT1 augments neointima formation by promoting mobilization of smooth muscle progenitors via platelet-derived SDF-1{alpha}.

Objective: Bone marrow (BM)-derived endothelial progenitor cells (EPCs) and vascular smooth muscle progenitor cells (VPCs) contribute to neointima formation, whereas the angiotensin II (Ang II) type 1 receptor (AT(1))-mediated action on BM-derived progenitors remains undefined.

Methods And Results: A wire-induced vascular injury was performed in the femoral artery of BM-chimeric mice whose BM was repopulated with AT(1)-deficient (BM-Agtr1(-/-)) or wild-type (BM-Agtr1(+/+)) cells. Neointima formation was profoundly reduced by 38% in BM-Agtr1(-/-) mice.

Bone marrow angiotensin AT1 receptor regulates differentiation of monocyte lineage progenitors from hematopoietic stem cells.

Background: The angiotensin II (Ang II) type 1 (AT(1)) receptor is expressed in bone marrow (BM) cells, whereas it remains poorly defined how Ang II regulates differentiation/proliferation of monocyte-lineage cells to exert proatherogenic actions.

Methods And Results: We generated BM chimeric apoE(-/-) mice repopulated with AT(1)-deficient (Agtr1(-/-)) or wild-type (Agtr1(+/+)) BM cells. The atherosclerotic development was significantly reduced in apoE(-/-)/BM-Agtr1(-/-) mice compared with apoE(-/-)/BM-Agtr1(+/+) mice, accompanied by decreased numbers of BM granulocyte/macrophage progenitors (GMP:c-Kit(+)Sca-1(-)Lin(-)CD34(+)CD16/32(+)) and peripheral blood monocytes.