Ann Sumin, Choi Yukyung, Yoon Yohan
Department of Food and Nutrition, Sookmyung Women's University, Seoul 04310, Republic of Korea.
Risk Analysis Research Center, Sookmyung Women's University, Seoul 04310, Republic of Korea.
Microorganisms. 2023 Feb 21;11(3):547. doi: 10.3390/microorganisms11030547.
The objective of this study was to evaluate the anti-inflammatory effect of SMFM2017-NK1 (LS1), SMFM2017-NK3 (LS2), and SMFM2017-NK2 (LF) on colitis using an animal model. DSS (dextran sulfate sodium salt) was orally injected into C57BL/6N mice to induce inflammation in the colon for seven days. Colitis mice models were treated with LS1, LS2, and LF, respectively, and GG (LGG) was used as a positive control. During oral administration of lactic acid bacteria, the weights of the mice were measured, and the disease activity index (DAI) score was determined by judging the degree of diarrhea and bloody stool. When comparing the differences between the minimum weight after DSS administration and the maximum weight after lactic acid bacteriaadministration were compared, the LF-treated group showed the highest weight gain at 8.91%. The DAI scores of the LF, LS2, and LGG groups were lower than that of the control group. After sacrifice, mRNA expression levels for proinflammatory cytokines (TNF-α, IL-1β, IL-6, and IFN-γ) and mediators (iNOS and COX-2) in the colon were measured. LF was selected as a superior strain for anti-inflammation in the colon. It was further analyzed to determine its biochemical characteristics, cytotoxicity, and thermal stability. Catalase and oxidase activities for LF were negative. In cytotoxicity and heat stability tests, the LF group had higher cell viability than the LGG group. The genome of LF was obtained, and 5682 CDS, 114 tRNA, 2 RNA, and 5 repeat regions were predicted. Especially, LF could be distinguished from the other three strains based on taxonomic profiling, specific orthologous genes of the strain, and genomic variants. The results of this study suggest that SMFM2017-NK2 is a novel strain with an anti-inflammatory effect on colitis.
本研究的目的是使用动物模型评估SMFM2017-NK1（LS1）、SMFM2017-NK3（LS2）和SMFM2017-NK2（LF）对结肠炎的抗炎作用。将硫酸葡聚糖钠盐（DSS）经口注射到C57BL/6N小鼠体内，诱导结肠炎症持续7天。分别用LS1、LS2和LF处理结肠炎小鼠模型，并将鼠李糖乳杆菌（GG，即LGG）用作阳性对照。在口服乳酸菌期间，测量小鼠体重，并通过判断腹泻和便血程度来确定疾病活动指数（DAI）评分。比较DSS给药后最低体重与乳酸菌给药后最高体重之间的差异时，LF处理组的体重增加最高，为8.91%。LF、LS2和LGG组的DAI评分低于对照组。处死小鼠后，测量结肠中促炎细胞因子（TNF-α、IL-1β、IL-6和IFN-γ）和介质（iNOS和COX-2）的mRNA表达水平。LF被选为结肠抗炎的优势菌株。进一步分析以确定其生化特性、细胞毒性和热稳定性。LF的过氧化氢酶和氧化酶活性均为阴性。在细胞毒性和热稳定性试验中，LF组的细胞活力高于LGG组。获得了LF的基因组，并预测了5682个编码序列（CDS）、114个转运RNA（tRNA）、2个RNA和5个重复区域。特别是，基于分类分析、该菌株的特定直系同源基因和基因组变异，LF可与其他三株菌株区分开来。本研究结果表明，SMFM2017-NK2是一种对结肠炎具有抗炎作用的新型菌株。
