Department of Bioscience and Oral Diagnosis, Institute of Science and Technology of São José dos Campos (São Paulo State University-Unesp), São José dos Campos, São Paulo, Brazil.
Private Practice, São José dos Campos, São Paulo, Brazil.
PLoS One. 2024 May 31;19(5):e0304358. doi: 10.1371/journal.pone.0304358. eCollection 2024.
Osteoporosis is an important health problem that occurs due to an imbalance between bone formation and resorption. Hormonal deficiency post-menopause is a significant risk factor. The probiotic Limosilactobacillus reuteri has been reported to prevent ovariectomy (Ovx)-induced bone loss in mice and reduce bone loss in postmenopausal women. Despite the numerous health benefits of probiotics, as they are live bacteria, the administration is not risk-free for certain groups (e.g., neonates and immunosuppressed patients). We evaluated the effects of L. reuteri (ATCC PTA 6475) and its heat-killed (postbiotic) form on Ovx-induced bone loss. Adult female mice (BALB/c) were randomly divided into four groups: group C-control (sham); group OVX-C-Ovx; group OVX-POS-Ovx + heat-killed probiotic; group OVX-PRO-Ovx + probiotic. L. reuteri or the postbiotic was administered to the groups (1.3x109 CFU/day) by gavage. Bacterial morphology after heat treatment was accessed by scanning electron microscopy (SEM). The treatment started one week after Ovx and lasted 28 days (4 weeks). The animals were euthanized at the end of the treatment period. Bone microarchitecture and ileum Occludin and pro-inflammatory cytokines gene expression were evaluated by computed microtomography and qPCR techniques, respectively. The Ovx groups had lower percentage of bone volume (BV/TV) and number of bone trabeculae as well as greater total porosity compared to the control group. Treatment with live and heat-killed L. reuteri resulted in higher BV/TV and trabecular thickness than the Ovx group. The heat treatment caused some cell surface disruptions, but its structure resembled that of the live probiotic in SEM analysis. There were no statistical differences in Occludin, Il-6 and Tnf-α gene expression. Both viable and heat-killed L. reuteri prevented bone loss on ovariectomized mice, independently of gut Occludin and intestinal Il-6 and Tnf-α gene expression.
骨质疏松症是一种由于骨形成和吸收之间失衡而引起的重要健康问题。绝经后激素缺乏是一个重要的危险因素。已报道益生菌罗伊氏乳杆菌可预防去卵巢（Ovx）诱导的小鼠骨丢失，并减少绝经后妇女的骨丢失。尽管益生菌具有许多健康益处，但由于它们是活菌，因此对于某些人群（例如新生儿和免疫抑制患者），使用并非没有风险。我们评估了罗伊氏乳杆菌（ATCC PTA 6475）及其热灭活（后生元）形式对 Ovx 诱导的骨丢失的影响。成年雌性小鼠（BALB/c）随机分为四组：C 组-对照（假手术）；OVX-C-Ovx 组；OVX-POS-Ovx + 热灭活益生菌组；OVX-PRO-Ovx + 益生菌组。通过灌胃向各组（1.3x109CFU/天）给予罗伊氏乳杆菌或后生元。细菌经热处理后的形态通过扫描电子显微镜（SEM）进行评估。Ovx 后一周开始治疗，持续 28 天（4 周）。治疗结束时处死动物。通过计算微断层扫描和 qPCR 技术分别评估骨微结构和回肠 Occludin 和促炎细胞因子基因表达。与对照组相比，Ovx 组的骨体积百分比（BV/TV）和骨小梁数量较低，总孔隙率较高。与 Ovx 组相比，活的和热灭活的 L. reuteri 治疗导致更高的 BV/TV 和小梁厚度。热处理导致一些细胞表面破裂，但在 SEM 分析中，其结构类似于活益生菌。Occludin、Il-6 和 Tnf-α基因表达无统计学差异。活的和热灭活的 L. reuteri 均可预防去卵巢小鼠的骨丢失，与肠道 Occludin 以及肠内 Il-6 和 Tnf-α基因表达无关。
