Perivascular adipose tissue contributes to large elastic artery stiffness with aging and is associated with greater superoxide bioavailability

Abstract

We tested the hypothesis that perivascular adipose tissue (PVAT) contributes to age‐related large elastic artery stiffening and is associated with greater superoxide production. PVAT from young (Y, 6 mo, n=5) and old (O, 27 mo, n=5) donor C57BL6/N mice was transplanted directly onto the abdominal aorta of Y recipient (6 mo) mice for 8 weeks. Y recipient mice transplanted with PVAT from O compared with Y donors had greater arterial stiffness as assessed by aortic pulse wave velocity (409 ± 7 vs. 342 ± 8 cm/s, P < 0.05) and ex vivo intrinsic mechanical stiffness (3197 ± 647 vs. 1889 ± 520 kPa, P < 0.05). Systolic (109 ± 5 vs. 111 ± 2 mmHg), diastolic (75 ± 5 vs. 82 ± 2 mmHg) and mean (86 ± 5 vs. 91 ± 2 mmHg) blood pressure did not differ between groups (n=3–4). Additional aortic segments from Y and O mice with (+) or without (−) PVAT (n=5–6) were cultured for 72 hours followed by intrinsic mechanical testing. Aortic segments from O+PVAT (3947 ± 276 kPa, P <0.05) had greater stiffness compared with Y+PVAT, Y−PVAT and O‐PVAT (2437 ± 226, 1768 ± 132 and 2668 ± 404 kPa, respectively); O‐PVAT had greater mechanical stiffening than Y−PVAT (P < 0.05). PVAT superoxide production was greater in O vs. Y (13835 ± 2322 vs. 6657 ± 1720 AU, P < 0.05, n=5–6). Collectively, these data demonstrate PVAT contributes to large artery stiffening with aging and is associated with increased superoxide bioavailability.