LCWE诱导的小鼠川崎病模型中sEPCR、vWF、α-SMA、SM22α的表达与冠状动脉病变的观察

Observation of sEPCR, vWF, α-SMA, and SM22α Expression with Coronary Artery Lesions in the LCWE-Induced Mouse Model of Kawasaki Disease

摘要: 目的：观察LCWE诱导川崎病模型小鼠血浆中可溶性内皮细胞蛋白C受体(Soluble endothelial cell protein C receptor, sEPCR)、血管性血友病因子(von Willebrand factor, vWF)、α-平滑肌肌动蛋白(α-smooth muscle actin, α-SMA)、平滑肌22α (smooth muscle 22α, SM22α)的表达水平及与炎症反应和冠状动脉病变的关系。方法：4~6周龄C57BL/6雄性小鼠16只，分为模型组和对照组。模型组分为大、中、小三个剂量组，三组分别单次腹腔注射三种浓度(0.25 mg/ml, 0.5 mg/ml, 1.0 mg/ml)的干酪乳杆菌细胞壁提取物(Lactobacillus casei cell wall extract, LCWE) 1 ml来制备川崎病模型小鼠，对照组注射等容量PBS缓冲液。注射14 d后，采用ELISA方法检测4组小鼠血浆sEPCR、vWF、α-SMA、SM22α表达水平。采用苏木精–伊红染色法(HE染色法)检查冠状动脉及周围心肌组织、腹主动脉的病理变化。结果：与对照组相比，模型组小鼠冠状动脉及周围心肌组织、腹主动脉组织出现病理改变，且随着LCWE注射剂量的增加，浸润冠状动脉及周围心肌组织、腹主动脉组织的炎性细胞数量明显增加；炎症评分随着LCWE注射剂量的升高而升高；模型组小鼠血浆中sEPCR、vWF含量较对照组升高(P < 0.05)，LCWE注射剂量越大则升高越明显；α-SMA、SM22α含量较对照组明显降低(P < 0.05) LCWE注射剂量越大则降低越明显。将四组小鼠的炎症评分与血浆中四种生物标志物含量进行相关性分析发现：炎症评分与血浆中sEPCR、vWF的含量呈正相关，与α-SMA、SM22α的含量呈负相关。结论：LCWE可以诱发小鼠腹主动脉和心肌损伤，并可能诱发小鼠动脉平滑肌细胞由收缩型向合成型转换，小鼠血浆中sEPCR、vWF、α-SMA、SM22α的表达水平与LCWE注射剂量存在相关性。

Abstract: Objective: To observe the expression levels of soluble endothelial cell protein C receptor (sEPCR), von Willebrand factor (vWF), α-smooth muscle actin (α-SMA), and smooth muscle 22α (SM22α) in the plasma of a Kawasaki disease (KD) mouse model induced by Lactobacillus casei cell wall extract (LCWE), and to explore their relationship with inflammatory response and coronary artery lesions. Methods: Sixteen 4~6-week-old male C57BL/6 mice were divided into a model group and a control group. The model group was further subdivided into three subgroups based on LCWE dosage: low-dose (0.25 mg/mL), medium-dose (0.5 mg/mL), and high-dose (1.0 mg/mL). Each subgroup received a single intraperitoneal injection of 1 mL of LCWE at the corresponding concentration to establish the KD mouse model, while the control group was injected with an equal volume of PBS buffer. Fourteen days after injection, ELISA was used to measure plasma levels of sEPCR, vWF, α-SMA, and SM22α in all groups. Pathological changes in the coronary arteries, surrounding myocardial tissue, and abdominal aorta were examined using hematoxylin-eosin (HE) staining. Results: Compared with the control group, the model group exhibited pathological alterations in the coronary arteries, surrounding myocardial tissue, and abdominal aorta. As the LCWE dosage increased, the number of inflammatory cells infiltrating these tissues significantly rose, and the inflammation score increased accordingly. Plasma levels of sEPCR and vWF were elevated in the model group (P < 0.05), with higher LCWE doses leading to greater increases, while α-SMA and SM22α levels were significantly reduced (P < 0.05), with larger LCWE doses resulting in more pronounced decreases. Correlation analysis between inflammation scores and plasma biomarker levels revealed that inflammation scores positively correlated with sEPCR and vWF levels but negatively correlated with α-SMA and SM22α levels. Conclusion: LCWE can induce abdominal aortic and myocardial injury in mice and may promote the transition of arterial smooth muscle cells from a contractile to a synthetic phenotype. The expression levels of sEPCR, vWF, α-SMA, and SM22α in mouse plasma are dose-dependent on LCWE injection.