2024 年第 9 期 第 0 卷

CD+4T淋巴细胞穿孔素基因启动子低甲基化水平在戒烟大鼠肺气肿进展中的作用及S-腺苷甲硫氨酸的干预效果

The role of low methylation levels of the CD+4T lymphocyte perforin gene promoter in the progression of emphysema in smoking cessation rats and the intervention effect of S-adenosylmethionine

作者：卢江桃1张艳梅2程贵容2张程1,3

英文作者：Lu Jiangtao1 Zhang Yanmei2 Cheng Guirong2 Zhang Cheng13

单位：1贵州医科大学临床医学院，贵阳550004；2遵义医科大学研究生院，遵义563000；3贵州省人民医院呼吸与危重症医学科国家卫生健康委员会肺脏免疫性疾病诊治重点实验室，贵阳550002

英文单位：1Clinical Medical College Guizhou Medical University Guiyang 550004 China; 2Graduate School Zunyi Medical University Zunyi 563000 China; 3Department of Respiratory and Critical Care Medicine Guizhou Provincial People′s Hospital Key Laboratory of Diagnosis and Treatment of Pulmonary Immune Disease of National Health Commission Guiyang 550002 China

关键词：肺气肿；戒烟大鼠；CD+4T淋巴细胞穿孔素基因启动子甲基化水平

英文关键词：Emphysema;Smokingcessationrats;CD+4Tlymphocyteperforingenepromotermethylationlevels

• 摘要：

• 目的 探讨CD+4T淋巴细胞穿孔素基因启动子甲基化水平与戒烟后大鼠肺气肿持续进展的关系及S-腺苷甲硫氨酸（SAM）的干预效果。方法 将20只SD大鼠随机分为4组：正常对照组、模型组、戒烟4周组、戒烟后SAM干预4周组，各5只，后3组香烟烟雾暴露法建立大鼠肺气肿模型并采取相应措施。各组取右下肺组织行苏木精-伊红（HE）染色观察病理学改变，测量平均内衬间隔（MLI）和平均肺泡数（MAN）。用免疫磁珠法从各组大鼠的脾脏中分选出CD+4T淋巴细胞，提取其DNA，检测CD+4T淋巴细胞穿孔素基因启动子区域的甲基化水平。结果 模型组、戒烟4周组、戒烟后SAM干预4周组MLI均较正常对照组增加（均P＜0.05），其中戒烟4周组较模型组、戒烟后SAM干预4周组增加（均P＜0.05）。模型组、戒烟4周组、戒烟后SAM干预4周组MAN均较正常对照组减小（均P＜0.05），其中戒烟4周组较模型组减小（P＜0.05）。模型组和戒烟4周组CD+4T淋巴细胞穿孔素基因启动子甲基化水平均低于正常对照组和戒烟后SAM干预4周组［（93.9±3.1）%、（93.1±1.8）%比（97.1±1.1）%、（96.4±1.5）%］（均P＜0.05）。结论 CD+4T淋巴细胞穿孔素基因启动子低甲基化水平在大鼠戒烟后仍持续存在，可能是戒烟后大鼠肺气肿不断恶化的原因之一；而给予SAM干预后，戒烟大鼠的肺气肿恶化可好转。

• Objective To investigate the relationship between the methylation levels of the CD+4 T lymphocyte perforin gene promoter and the continuous progression of pulmonary emphysema in rats after smoking cessation, as well as the intervention effect of S-adenosylmethionine (SAM). Methods Twenty SD rats were randomly divided into 4 groups: normal control group, model group, 4-week smoking cessation group, and 4-week smoking cessation with SAM intervention group, each comprising 5 rats, the last three groups rat emphysema model was established using cigarette smoke exposure method and taked corresponding measures. Right lower lung tissues were collected from each group for histopathological observation after staining with hematoxylin-eosin (HE), and mean linear intercept (MLI) and mean alveolar number (MAN) were measured. CD+4 T lymphocytes were isolated from the spleens of rats in each group using immunomagnetic bead method, DNA was extracted, and the methylation level of the CD+4 T lymphocyte perforin gene promoter region was detected. Results The model group, the 4-week smoking cessation group, and the 4-week smoking cessation with SAM intervention group all showed significant increases in MLI compared to the normal control group (all P＜0.05). Specifically, the 4-week smoking cessation group showed greater increases compared to the model group and the 4-week smoking cessation with SAM intervention group (both P＜0.05). Moreover, the model group, the 4-week smoking cessation group, and the 4-week smoking cessation with SAM intervention group demonstrated decrease in MAN compared to the normal control group (all P＜0.05), with the 4-week smoking cessation group showing a greater decrease compared to the model group (P＜0.05). Additionally, the methylation levels of CD+4 T lymphocyte perforin gene promoter in the model group and the 4-week smoking cessation group were lower than those in the normal control group and the 4-week smoking cessation with SAM intervention group ［(93.9±3.1)% and (93.1±1.8)% vs (97.1±1.1)% and (96.4±1.5)%］ (all P＜0.05). Conclusions The persistent low methylation levels observed in the perforin gene promoter of CD+4 T lymphocytes in rats following smoking cessation may contribute to the ongoing deterioration of emphysema in this population. However, following intervention with SAM, the deterioration of pulmonary emphysema in smoking cessation rats could be reversed.