title: Baicalin inhibits Staphylococcus aureus-induced apoptosis by regulating TLR2 and TLR2-related apoptotic factors in the mouse mammary glands.
abstract: Baicalin, the major active constituent of the isolated root of Scutellaria baicalensis, is widely used in China and Southeast Asian countries. Evidence has indicated that baicalin has multiple biological activities, including anti-apoptotic properties. Mastitis is a severe problem in humans and other animals and is characterized by mammary gland cell apoptosis. Staphylococcus aureus (S. aureus) is the major pathogen that causes mastitis. This study was designed to evaluate the protective effects of baicalin on the mammary glands during S. aureus-induced mastitis. In the present study, a mouse model was infected with S. aureus to induce mammary gland injury. Baicalin treatment was administered between 6 and 24h after infection. Toll-like receptor 2, p53, BAX, BCL-2 and caspase-3 expression were analyzed using qPCR and Western blotting. The results indicated that baicalin significantly attenuated pathological damage and cell death in the mammary glands. Further studies revealed that baicalin down-regulated the expression of Toll-like receptor 2 (TLR2) and the phosphorylation of p53 in the mammary glands after S. aureus-induced mastitis. Baicalin also promoted the expression of BCL-2 at the mRNA and protein levels but inhibited BAX and caspase-3 (CASP-3) cleavage. Baicalin inhibited apoptosis and had protective effects on mammary gland tissues during S. aureus-induced mastitis. These effects were displayed by reductions in TLR2 expression and p53 phosphorylation and the regulation of apoptosis-related factors (BCL-2, BAX and CASP-3) in mammary gland tissues.
authors.affiliation: Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin Province 130062, People's Republic of China.
authors.forename: Mengyao
authors.initials: M
authors.lastname: Guo
authors.affiliation: Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin Province 130062, People's Republic of China.
authors.forename: Yongguo
authors.initials: Y
authors.lastname: Cao
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.affiliation: Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin Province 130062, People's Republic of China.
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Song
authors.affiliation: Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin Province 130062, People's Republic of China.
authors.forename: Zhicheng
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin Province 130062, People's Republic of China.
authors.forename: Ershun
authors.initials: E
authors.lastname: Zhou
authors.affiliation: Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin Province 130062, People's Republic of China.
authors.forename: Xuming
authors.initials: X
authors.lastname: Deng
authors.affiliation: Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin Province 130062, People's Republic of China. Electronic address: zhangns@jlu.edu.cn.
authors.forename: Naisheng
authors.initials: N
authors.lastname: Zhang
authors.affiliation: Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Jilin University, Changchun, Jilin Province 130062, People's Republic of China. Electronic address: yangzhengtao01@sina.com.
authors.forename: Zhengtao
authors.initials: Z
authors.lastname: Yang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D053148:Caspase 3 / Q000378:metabolism; D005260:Female; D005419:Flavonoids / Q000494:pharmacology* / Q000627:therapeutic use; D008321:Mammary Glands, Animal / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology / Q000648:ultrastructure; D008413:Mastitis / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D013203:Staphylococcal Infections / Q000150:complications; D013211:Staphylococcus aureus; D051195:Toll-Like Receptor 2 / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000235:genetics / Q000378:metabolism
chemical_list: C494827:Bax protein, mouse; D005419:Flavonoids; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D051195:Toll-Like Receptor 2; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein; C038044:baicalin; D053148:Caspase 3
keywords: Apoptosis; Baicalin; Mastitis; Staphylococcus aureus; Toll-like Receptor 2