OBJECTIVE: To determine the increase of apoptosis and the decrease of smooth muscle cells (SMCs) density in human abdominal aortic aneurysms (AAA). METHODS: In situ terminal transferase-mediated dUTP nick end labeling (TUNEL) was employed to detect apoptosis of SMCs in patients with AAA (n = 25) and normal abdominal aortae (n = 10). Positive cells were identified by specific cell marker in combination with immunohistochemistry. Meanwhile SMC counting was performed by anti-alpha-actin immunohistostaining to compare the SMC density. RESULTS: TUNEL staining revealed that there was significantly increased apoptosis in AAAs (average 8.6%) compared with normal abdominal aortae (average 0.95%, P < 0.01). Double staining showed that most of these cells were SMCs. Counting of alpha-actin positive SMCs revealed that medial SMC density of AAAs (37.5 +/- 7.6 SMCs/HPF) was reduced by 79.1% in comparison with that of normal abdominal aortae (179.2 +/- 16.1 SMCs/HPF, P < 0.01). CONCLUSIONS: Significantly increased SMCs of AAA bear apoptotic markers initiating cell death. Elevated apoptosis may result in a decreased density of SMCs in AAA, which may profoundly influence the development of AAA.
OBJECTIVE: To determine the increase of apoptosis and the decrease of smooth muscle cells (SMCs) density in humanabdominal aortic aneurysms (AAA). METHODS: In situ terminal transferase-mediated dUTP nick end labeling (TUNEL) was employed to detect apoptosis of SMCs in patients with AAA (n = 25) and normal abdominal aortae (n = 10). Positive cells were identified by specific cell marker in combination with immunohistochemistry. Meanwhile SMC counting was performed by anti-alpha-actin immunohistostaining to compare the SMC density. RESULTS: TUNEL staining revealed that there was significantly increased apoptosis in AAAs (average 8.6%) compared with normal abdominal aortae (average 0.95%, P < 0.01). Double staining showed that most of these cells were SMCs. Counting of alpha-actin positive SMCs revealed that medial SMC density of AAAs (37.5 +/- 7.6 SMCs/HPF) was reduced by 79.1% in comparison with that of normal abdominal aortae (179.2 +/- 16.1 SMCs/HPF, P < 0.01). CONCLUSIONS: Significantly increased SMCs of AAA bear apoptotic markers initiating cell death. Elevated apoptosis may result in a decreased density of SMCs in AAA, which may profoundly influence the development of AAA.
Authors: Karlijn B Rombouts; Tara A R van Merrienboer; Johannes C F Ket; Natalija Bogunovic; Jolanda van der Velden; Kak Khee Yeung Journal: Eur J Clin Invest Date: 2021-11-21 Impact factor: 5.722