加藤 尚也

BACKGROUND AND AIM: Werner syndrome (WS) is an autosomal recessive, adult-onset, progeroid syndrome caused by WRN mutations. As refractory skin ulcers significantly affect the quality of life of patients with WS, this study identified ulcer risk factors and assessed prevention methods. METHODS: We analyzed the data of 51 patients with WS enrolled in the Japanese Werner Syndrome Registry between 2016 and 2022. A cross-sectional analysis was performed to determine the association with skin ulcers at baseline. Statistical analyses were conducted, including Welch's and Pearson's chi-square tests. Age was adjusted using a logistic regression model. RESULTS: The mean patient age was 48.8±7.6 years, and 66.7% of patients presented with skin ulcers. Univariate analysis showed that patients with skin ulcers were older than those without ulcers. Systolic blood pressure (SBP) was higher in patients with skin ulcers. Patients without skin ulcers received metformin and pioglitazone treatment significantly more often than those with ulcers. Logistic regression analysis adjusted for age showed that higher SBP remained a significant risk factor for skin ulcers. Patients administered pioglitazone had lower ulcer morbidity. CONCLUSIONS: Age and SBP are risk factors for skin ulcers in patients with WS. Moreover, pioglitazone treatment may prevent skin ulcers.

The underlying mechanisms of atherosclerosis, the second leading cause of death among Werner syndrome (WS) patients, are not fully understood. Here, we establish an in vitro co-culture system using macrophages (iMφs), vascular endothelial cells (iVECs), and vascular smooth muscle cells (iVSMCs) derived from induced pluripotent stem cells. In co-culture, WS-iMφs induces endothelial dysfunction in WS-iVECs and characteristics of the synthetic phenotype in WS-iVSMCs. Transcriptomics and open chromatin analysis reveal accelerated activation of type I interferon signaling and reduced chromatin accessibility of several transcriptional binding sites required for cellular homeostasis in WS-iMφs. Furthermore, the H3K9me3 levels show an inverse correlation with retrotransposable elements, and retrotransposable element-derived double-stranded RNA activates the DExH-box helicase 58 (DHX58)-dependent cytoplasmic RNA sensing pathway in WS-iMφs. Conversely, silencing type I interferon signaling in WS-iMφs rescues cell proliferation and suppresses cellular senescence and inflammation. These findings suggest that Mφ-specific inhibition of type I interferon signaling could be targeted to treat atherosclerosis in WS patients.