title: Stevioside plays an anti-inflammatory role by regulating the NF-κB and MAPK pathways in S. aureus-infected mouse mammary glands.
abstract: Mastitis is an inflammatory disease caused by microbial infection. Staphylococcus aureus is one of the primary bacteria responsible for mastitis. Stevioside is isolated from Stevia rebaudiana and is known to have therapeutic functions. This study was designed to evaluate the effects of stevioside in a mouse model of S. aureus-induced mastitis. In this study, the mouse mammary gland was infected with S. aureus to induce the mastitis model. The stevioside was administered intraperitoneally after the S. aureus infection was established. Hematoxylin-eosin (HE) staining, ELISA, Western blot, and q-PCR methods were used. The results show that stevioside significantly reduced the inflammatory cell infiltration and the levels of TNF-α, IL-1β, and IL-6 and the respective expression of their messenger RNAs (mRNAs). Further studies revealed that stevioside downregulated the TLR2, NF-κB, and (mitogen-activated protein kinase) MAPK signaling pathways in the S. aureus-infected mouse mammary gland. Our results demonstrate that stevioside reduced the expression of TNF-α, IL-1β, and IL-6 by inhibiting the phosphorylation of proteins in the NF-κB and MAPK signaling pathways dose-dependently, but that their mRNA expression was not obviously changed.
authors.affiliation: Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin Province, 130062, People's Republic of China.
authors.forename: Tiancheng
authors.initials: T
authors.lastname: Wang
authors.forename: Mengyao
authors.initials: M
authors.lastname: Guo
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Song
authors.forename: Zecai
authors.initials: Z
authors.lastname: Zhang
authors.forename: Haichao
authors.initials: H
authors.lastname: Jiang
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Yunhe
authors.initials: Y
authors.lastname: Fu
authors.forename: Yongguo
authors.initials: Y
authors.lastname: Cao
authors.forename: Lianqin
authors.initials: L
authors.lastname: Zhu
authors.forename: Naisheng
authors.initials: N
authors.lastname: Zhang
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology / Q000627:therapeutic use; D045786:Diterpenes, Kaurane / Q000494:pharmacology / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005960:Glucosides / Q000494:pharmacology / Q000627:therapeutic use*; D020935:MAP Kinase Signaling System / Q000187:drug effects* / Q000502:physiology; D008321:Mammary Glands, Animal / Q000187:drug effects* / Q000378:metabolism / Q000382:microbiology; D008413:Mastitis / Q000188:drug therapy* / Q000378:metabolism / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D016328:NF-kappa B / Q000037:antagonists & inhibitors* / Q000378:metabolism; D013211:Staphylococcus aureus
chemical_list: D000893:Anti-Inflammatory Agents; D045786:Diterpenes, Kaurane; D005960:Glucosides; D016328:NF-kappa B; C012043:stevioside