Probiotic Administration Increases Mandibular Bone Mineral Density on Rats Exposed to Cigarette Smoke Inhalation

Abstract Smoking is one of the main risk factor for periodontal disease, increasing its prevalence and severity. Probiotics emerged as an alternative for the prevention and treatment of many diseases, since it can modulate the host immune response and modify the modify the microbiome. Therefore, the aim of the present study is to evaluate the effects of probiotic administration on the periodontal tissues in rats exposed to cigarette smoke inhalation (CSI). Forty rats were allocated into the following groups (n=10): group C (control, without CSI and probiotic); group PROB (control+probiotic); group CSI (CSI) and group CSI+PROB (CSI+probiotic). Groups PROB and CSI+PROB received 2g of an association of probiotic microorganisms incorporated into the feed during 6 months. Groups CSI and CSI+PROB were exposed to CSI for 60 min daily. After six months all the animals were euthanized and the hemi-mandibles were collected and processed for microcomputed tomography analyses. Regarding the body weight of the animals, feed consumption was similar among the groups, however, after the second month groups C and PROB showed higher body weight gain when compared to groups CSI and CSI+PROB (p<0.05). Group CSI presented reduced bone mineral density (BMD), whereas group PROB showed the highest values (p=0.01). It can be concluded that administration of probiotics promoted an increase in BMD and, consequently, a protective effect on the mandibular bone structures in rats exposed to inhalation of cigarette smoke.

摘要：吸烟是牙周疾病的主要危险因素之一，可升高其患病率并加重病情严重程度。益生菌可调节宿主免疫应答、调控微生物组，因此成为多种疾病防治的备选方案。本研究旨在探究益生菌干预对香烟烟雾暴露（cigarette smoke inhalation, CSI）大鼠牙周组织的影响。将40只大鼠随机分为4组（每组n=10）：C组（对照组，无香烟烟雾暴露及益生菌干预）、PROB组（对照组+益生菌干预）、CSI组（仅香烟烟雾暴露）以及CSI+PROB组（香烟烟雾暴露+益生菌干预）。PROB组与CSI+PROB组大鼠在6个月干预期间，每日饲喂添加2g复合益生菌制剂的饲料。CSI组与CSI+PROB组大鼠每日暴露于香烟烟雾环境60分钟，持续6个月。造模6个月后，对所有大鼠实施安乐死，采集半侧下颌骨标本并进行显微计算机断层扫描分析。各组大鼠的饲料摄入量无显著差异，但自造模第2个月起，C组与PROB组的体重增幅显著高于CSI组与CSI+PROB组（p<0.05）。CSI组大鼠的骨密度（bone mineral density, BMD）显著降低，而PROB组的骨密度值最高（p=0.01）。综上，益生菌干预可提升香烟烟雾暴露大鼠的骨密度，进而对其下颌骨结构起到保护作用。