title: Staphylococcus aureus induces apoptosis in primary bovine mammary epithelial cells through Fas-FADD death receptor-linked caspase-8 signaling.
abstract: Infections with Staphylococcus aureus, a common inducer of mastitis, often result in mammary gland damage and death of various cell types. Although S. aureus was suggested to induce apoptosis in a bovine mammary epithelial cell (BMEC) line, MAC-T, it is unknown whether primary BMECs (pBMECs) apoptosis is triggered by S. aureus and the associated underlying molecular mechanisms have not been determined. Here, we demonstrated that S. aureus induced apoptosis in pBMECs in a time- and dose-dependent manner. Further, S. aureus-induced apoptosis in pBMECs was associated with activation of caspase-3 and caspase-8, but caspase-9 was not. In addition, pBMECs apoptosis was mitigated by caspase-3 and caspase-8 inhibitors, suggesting that apoptosis is initiated via caspase-8 activation. Moreover, S. aureus infection significantly increased expressions of Fas and Fas-associated death domain (FADD) of pBMECs. Taken together, our results demonstrated that S. aureus induced apoptosis in pBMECs via the Fas-FADD death receptor and subsequently triggered the caspase-8-dependent signaling.
authors.affiliation: College of Life Sciences, Inner Mongolia University , Hohhot, People's Republic of China .
authors.forename: Qingliang
authors.initials: Q
authors.lastname: Hu
authors.forename: Xinjie
authors.initials: X
authors.lastname: Cui
authors.forename: Lin
authors.initials: L
authors.lastname: Tao
authors.forename: Lei
authors.initials: L
authors.lastname: Xiu
authors.forename: Ting
authors.initials: T
authors.lastname: Wang
authors.forename: Xiao
authors.initials: X
authors.lastname: Wang
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D053148:Caspase 3; D053181:Caspase 8 / Q000378:metabolism*; D061945:Caspase Inhibitors / Q000494:pharmacology; D002417:Cattle; D002460:Cell Line; D004847:Epithelial Cells / Q000378:metabolism*; D053200:Fas-Associated Death Domain Protein / Q000378:metabolism; D005260:Female; D008321:Mammary Glands, Animal / Q000473:pathology*; D008414:Mastitis, Bovine / Q000473:pathology*; D015398:Signal Transduction; D013203:Staphylococcal Infections / Q000473:pathology / Q000662:veterinary*; D013211:Staphylococcus aureus; D019014:fas Receptor / Q000378:metabolism
chemical_list: D061945:Caspase Inhibitors; D053200:Fas-Associated Death Domain Protein; D019014:fas Receptor; D053148:Caspase 3; D053181:Caspase 8