Abstract 5104: Direct Observation of Adipose Tissue-induced Leukocyte Recruitment to the Artery Wall: A Direct Link Between Obesity and Atherosclerosis
Background: Though inflammation within adipose tissues play a role in pathogenesis of metabolic syndrome, a causative connection between adipose tissue and atherosclerosis is not fully understood. The present study aimed to examine the direct effect of adipose tissue on macrovascular inflammation by intravital microscopic analysis of the femoral artery of mice after perivascular adipose tissue transplantation.
Methods and Results Subcutaneous (SQ) or visceral (VIS) adipose tissue harvested from C57/BL6 mice was transplanted to the perivascular area of the femoral artery of recipient C57/BL6 mice. A quantitative intravital microscopic analysis was performed on the artery. The number of adherent leukocyte was increased after adipose tissue transplantation in a time-dependent manner (1day to 7days). VIS transplantation induced significantly more leukocyte accumulation than SQ at 7 days after transplantation. Simultaneous flow cytometry showed the expression of CD11b was significantly increased on peripheral neutrophils and monocytes. Interestingly, the amount of oxidative stress was not changed after transplantation. We found significant increase of MCP-1, MIP-1β, and IL-6 in the recipient serum after transplantation. Further, the expression level of MCP-1 was significantly increased in the donor adipose tissues.
Conclusion These data indicate that adipose tissue directly stimulates athero-prone vascular inflammation. The underlying mechanisms seem to involve induction of MCP-1 from adipose tissues.