Cardiovascular and Metabolic Disorders Program, Duke-National University of Singapore Medical School, Singapore.
Cardiovascular and Metabolic Disorders Program, Duke-National University of Singapore Medical School, Singapore; National Heart Research Institute Singapore, National Heart Centre Singapore, Singapore.
Gastroenterology. 2019 Sep;157(3):777-792.e14. doi: 10.1053/j.gastro.2019.05.002. Epub 2019 May 9.
BACKGROUND & AIMS: We studied the role of interleukin 11 (IL11) signaling in the pathogenesis of nonalcoholic steatohepatitis (NASH) using hepatic stellate cells (HSCs), hepatocytes, and mouse models of NASH.
We stimulated mouse and human fibroblasts, HSCs, or hepatocytes with IL11 and other cytokines and analyzed them by imaging, immunoblot, and functional assays and enzyme-linked immunosorbent assays. Mice were given injections of IL11. Mice with disruption of the interleukin 11 receptor subunit alpha1 gene (Il11ra1) mice and Il11ra1 mice were fed a high-fat methionine- and choline-deficient diet (HFMCD) or a Western diet with liquid fructose (WDF) to induce steatohepatitis; control mice were fed normal chow. db/db mice were fed with methionine- and choline-deficient diet for 12 weeks and C57BL/6 NTac were fed with HFMCD for 10 weeks or WDF for 16 weeks. Some mice were given intraperitoneal injections of anti-IL11 (X203), anti-IL11RA (X209), or a control antibody at different timepoints on the diets. Livers and blood were collected; blood samples were analyzed by biochemistry and liver tissues were analyzed by histology, RNA sequencing, immunoblots, immunohistochemistry, hydroxyproline, and mass cytometry time of flight assays.
HSCs incubated with cytokines produced IL11, resulting in activation (phosphorylation) of ERK and expression of markers of fibrosis. Livers of mice given injections of IL11 became damaged, with increased markers of fibrosis, hepatocyte cell death and inflammation. Following the HFMCD or WDF, livers from Il11ra1 mice had reduced steatosis, fibrosis, expression of markers of inflammation and steatohepatitis, compared to and Il11ra1 mice on the same diets. Depending on the time of administration of anti-IL11 or anti-IL11RA antibodies to wild-type mice on the HFMCD or WDF, or to db/db mice on the methionine and choline-deficient diet, the antibodies prevented, stopped, or reversed development of fibrosis and steatosis. Blood samples from Il11ra1 mice fed the WDF and given injections of anti-IL11 or anti-IL11RA, as well as from Il11ra1 mice fed WDF, had lower serum levels of lipids and glucose than mice not injected with antibody or with disruption of Il11ra1.
Neutralizing antibodies that block IL11 signaling reduce fibrosis, steatosis, hepatocyte death, inflammation and hyperglycemia in mice with diet-induced steatohepatitis. These antibodies also improve the cardiometabolic profile of mice and might be developed for the treatment of NASH.
我们通过肝星状细胞（HSCs）、肝细胞和非酒精性脂肪性肝炎（NASH）的小鼠模型研究了白细胞介素 11（IL11）信号在 NASH 发病机制中的作用。
我们用 IL11 和其他细胞因子刺激小鼠和人成纤维细胞、HSCs 或肝细胞，通过成像、免疫印迹和功能测定以及酶联免疫吸附测定进行分析。给小鼠注射 IL11。用白细胞介素 11 受体亚单位 alpha1 基因（Il11ra1）敲除小鼠和 Il11ra1 小鼠给予高脂肪蛋氨酸和胆碱缺乏饮食（HFMCD）或含液体果糖的西方饮食（WDF），以诱导脂肪性肝炎；对照小鼠给予普通饲料。db/db 小鼠给予蛋氨酸和胆碱缺乏饮食 12 周，C57BL/6 NTac 给予 HFMCD 10 周或 WDF 16 周。一些小鼠在不同时间点给予腹腔注射抗 IL11（X203）、抗 IL11RA（X209）或对照抗体。收集肝脏和血液；血液样本通过生化分析，肝脏组织通过组织学、RNA 测序、免疫印迹、免疫组化、羟脯氨酸和质谱时间飞行分析进行分析。
用细胞因子孵育的 HSCs 产生 IL11，导致 ERK 激活（磷酸化）和纤维化标志物的表达。给予 IL11 注射的小鼠肝脏受损，纤维化标志物、肝细胞死亡和炎症增加。在用 HFMCD 或 WDF 处理后，与同饮食的 Il11ra1 小鼠相比，Il11ra1 小鼠的肝脏脂肪变性、纤维化、炎症和脂肪性肝炎标志物表达减少。根据在 HFMCD 或 WDF 上给予野生型小鼠或 db/db 小鼠抗 IL11 或抗 IL11RA 抗体的时间，或在蛋氨酸和胆碱缺乏饮食上给予 Il11ra1 小鼠，抗体可预防、阻止或逆转纤维化和脂肪变性的发展。用 WDF 喂养的 Il11ra1 小鼠的血液样本和给予抗 IL11 或抗 IL11RA 注射的 Il11ra1 小鼠以及用 WDF 喂养的 Il11ra1 小鼠的血液样本，其血清脂质和葡萄糖水平低于未注射抗体或 Il11ra1 缺失的小鼠。
中和阻断 IL11 信号的抗体可减少饮食诱导的脂肪性肝炎小鼠的纤维化、脂肪变性、肝细胞死亡、炎症和高血糖。这些抗体还改善了小鼠的心脏代谢特征，可能被开发用于治疗 NASH。
