Cheng Jia, Tong Jingdi, Li Can, Wang Ziyan, Li Hao, Ren Meiyi, Song Jinshang, Song Deyuan, Xie Qinna, Liu Mingchao
Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Hebei Agricultural University, Baoding 071001, China.
Vet Sci. 2025 Apr 1;12(4):323. doi: 10.3390/vetsci12040323.
is a major cause of bovine mastitis worldwide, making it difficult to control due to its resistance to multiple drugs. has been explored as a promising new approach to fighting bovine mastitis. In this study, the probiotic potential and safety of SDN1.2, as well as its ex vivo and in vivo anti-inflammatory effects against -induced mastitis, were comprehensively investigated using bioinformatics analyses and experimental validation methods. The results revealed that SDN1.2 exhibits non-hemolytic activity, is not cytotoxic, lacks virulence genes (e.g., adhesion factors, toxins, and invasion factors) and antibiotic resistance genes (e.g., beta-lactamases and tetracycline resistance genes), as supported by whole-genome sequencing, and significantly inhibits the growth of , as evaluated by antimicrobial tests. Following further validation in vitro, SDN1.2 demonstrated the capability to inhibit the adhesion and invasion of to bMECs. In a mouse model of -induced mastitis, SDN1.2 reduced the extent of neutrophil infiltration and inflammatory lesions. Furthermore, SDN1.2 pretreatment significantly reduced myeloperoxidase (MPO) activity and the expression of inflammatory cytokines (, , and ) in mouse mammary gland tissue. In -infected bMECs, SDN1.2 significantly lowered lactate dehydrogenase (LDH) levels and expression of inflammatory cytokines such as , , and . The results demonstrated that the newly isolated SDN1.2 from bovine sources exhibits promising characteristics as a safe probiotic for the alleviation of bovine mastitis due to its safety profile and anti-inflammatory and antibacterial properties.
是全球范围内牛乳腺炎的主要病因，因其对多种药物具有抗性，难以控制。作为一种对抗牛乳腺炎有前景的新方法已被探索。在本研究中，使用生物信息学分析和实验验证方法，全面研究了SDN1.2的益生菌潜力和安全性，以及其对诱导的乳腺炎的体外和体内抗炎作用。结果表明，全基因组测序支持SDN1.2表现出非溶血活性，无细胞毒性，缺乏毒力基因（如粘附因子、毒素和侵袭因子）和抗生素抗性基因（如β-内酰胺酶和四环素抗性基因），并且抗菌试验评估显示其显著抑制的生长。在体外进一步验证后，SDN1.2证明了抑制对牛乳腺上皮细胞（bMECs）的粘附和侵袭的能力。在诱导的乳腺炎小鼠模型中，SDN1.2减少了中性粒细胞浸润和炎症损伤的程度。此外，SDN1.2预处理显著降低了小鼠乳腺组织中髓过氧化物酶（MPO）活性和炎症细胞因子（、和）的表达。在感染的bMECs中，SDN1.2显著降低了乳酸脱氢酶（LDH）水平以及、和等炎症细胞因子的表达。结果表明，从牛源新分离的SDN1.2因其安全性概况以及抗炎和抗菌特性，作为一种缓解牛乳腺炎的安全益生菌展现出有前景的特性。
