Overexpression of PTPN2 in Visceral Adipose Tissue Ameliorated Atherosclerosis via T Cells Polarization Shift in Diabetic Apoe-/- Mice.

BACKGROUND/AIMS: Dysregulated inflammation in adipose tissue, marked by increased pro-inflammatory T-cell accumulation and reduced regulatory T cells (Treg), contributes to diabetes-associated insulin resistance and atherosclerosis. However, the molecular mechanisms underlying T-cell-mediated inflammation in adipose tissue remain largely unknown.

METHODS

Sixty apolipoprotein E (ApoE-/-) mice were randomly divided into chow and diabetes groups. Diabetes was induced by a high-fat and high-sugar diet combined with low-dose streptozotocin. Then we transferred a recombinant adenovirus carrying the protein tyrosine phosphatase non-receptor type 2 (PTPN2) gene into epididymal white adipose tissue (EWAT) of ApoE-/- mice. After transfection, all mice were euthanized to evaluate the effects of PTPN2 on T cells polarization and atherosclerosis.

RESULTS

PTPN2 was downregulated in EWAT of diabetic ApoE-/- mice. PTPN2 overexpression in EWAT reversed the high Th1/Treg and Th17/Treg ratios in EWAT of diabetic mice. In addition, PTPN2 overexpression in EWAT could significantly reduce macrophages infiltration, the ratio of M1/M2 macrophages and the expression of pro-inflammatory cytokines in EWAT, improving insulin resistance. In aortic root lesions, the vulnerability index were significantly decreased by overexpression of PTPN2 in EWAT.

CONCLUSION

These data suggested that PTPN2 overexpression in EWAT would inhibit systemic inflammation and increase the plaque stability via T cells polarization shift in diabetic mice.