Hyaluronic acid in tobacco-exposed rats. Inflammatory reaction, and duration of effect

Abstract Purpose: To evaluate the hyaluronic acid (HA) inflammatory reaction, fibroblasts, fibrosis and duration of effect in the dorsal region of tobacco-exposed rats. Methods: Ten Wistar rats were divided into two groups: tobacco-exposed-group (TEG;n=5) and air-control-group (CG;n=5). The TEG animals were tobacco-exposed twice a day, 30-minutes/session, during 60 days. After this period, all animals received 0.1 mL HA subcutaneous injection in the dorsal area. The volume of HA was measured immediately after HA injection and weekly using a hand-caliper in nine weeks. After this period, all the animals were euthanized, and a specimen of was collected to evaluate inflammatory cells, fibroblasts, and fibrosis by HE. Results: This study showed a higher inflammatory reaction in TEG than CG: inflammatory cell-count (CG: 1.07±0.9; TEG: 8.61±0.36, p<0.001); fibroblast count (CG: 2.92±0.17; TEG: 19.14±0.62, p<0.001), and fibrosis quantification (CG: 2.0; TEG: 3.75, p<0.001). The analysis of the HA volume in nine weeks in the dorsal region did not show a difference between groups (p=0.39). Conclusions: This study suggested that the HA injection in the TEG caused an increase in inflammatory cell count, fibroblast, and fibrosis quantification when compared to the CG. There was no difference in the duration of effect of HA between the groups.

摘要
研究目的：评估烟草暴露大鼠背部区域的透明质酸（hyaluronic acid, HA）炎症反应、成纤维细胞状态、纤维化程度及作用持续时长。
研究方法：将10只Wistar大鼠分为两组，烟草暴露组（TEG；n=5）与空气对照组（CG；n=5）。烟草暴露组大鼠每日暴露于烟草环境2次，每次30分钟，持续60天。造模结束后，所有大鼠均于背部区域皮下注射0.1 mL透明质酸。分别于注射后即刻及后续9周内每周采用手持游标卡尺测量注射部位的HA体积。实验末期全部大鼠实施安乐死，采集组织标本，通过HE染色法检测炎症细胞、成纤维细胞及纤维化水平。
研究结果：本研究显示，烟草暴露组的炎症反应程度显著高于空气对照组：炎症细胞计数（对照组：1.07±0.9；烟草暴露组：8.61±0.36，p<0.001）、成纤维细胞计数（对照组：2.92±0.17；烟草暴露组：19.14±0.62，p<0.001）及纤维化量化评分（对照组：2.0；烟草暴露组：3.75，p<0.001）均显著升高。对大鼠背部区域9周内的HA体积分析显示，两组间无统计学差异（p=0.39）。
结论：本研究表明，与空气对照组相比，烟草暴露组大鼠接受透明质酸注射后，其炎症细胞计数、成纤维细胞数量及纤维化量化评分均显著升高；且两组间透明质酸的作用持续时长无显著差异。