Cholesterol crystals as the main trigger of interleukin-6 production through innate inflammation in human spontaneously ruptured aortic plaques

• Published in: European heart journal Vol. 44; no. Supplement_2
• Main Authors: Komatsu, S, Yutani, C, Takahashi, S, Takewa, M, Iwa, N, Noda, H, Ohara, T, Kodama, K
• Format: Journal Article
• Language: English
• Published: 09.11.2023
• ISSN: 0195-668X; 1522-9645
• DOI: 10.1093/eurheartj/ehad655.3241

Abstract Aim Cholesterol crystals (CCs) may provoke innate inflammation in experimental and animal model, however, whether CCs are bystanders or play central role for plaque rupture is unknown. This study aimed to clarify whether CCs was the main trigger of innate inflammation in human spontaneously ruptured aortic plaques (SRAPs). Methods This study included 260 SRAPs collected during non-obstructive general angioscopy (NOGA) from 126 patients with having or suspected CAD. Interleukin (IL)-6 levels in SRAPs were measured. IL-6 level at the Valsalva sinus, and femoral or brachial arteries were measured. IL-6 ratios, IL-6 level in SRAPs and arteries divided by IL-6 level at the Valsalva sinus at the beginning of aorta, were calculated. The number of CCs were counted in sampled blood. The correlation between the count of CCs and IL-6 levels in SRAPs and that between the counts of CCs and IL-6 ratios in SRAPs were analyzed. Results IL-6 ratios of the brachial and femoral arteries were 1.06 (95% CI, 0.99–1.20) and 1.11 (95% CI, 1.04–1.20), respectively. IL-6 ratio in SRAPs was 1.10 [1.00, 1.26]. (median [IQR]). CCs were detected in 94 of 260 SRAPs (36%). The count of CCs was 11,590 (95% CI: 2,386–30,113] per 10 mL in CCs positive samples. There was a moderate correlation between the counts of CCs and IL-6 ratios in SRAPs (r=0.496, r<0.0001)(Fig. 1), whereas there was no correlation between the count of CCs and IL-6 levels in SRAPs.(Fig. 2) Conclusions By the in-situ study, CC might be the main trigger of IL-6 through innate inflammation in human SRAPs.Fig 1Fig 2