Reduction of mucin-1 gene expression associated with increased Escherichia coli adherence in the canine uterus in the early stage of dioestrus

• Published in: The veterinary journal (1997) Vol. 173; no. 2; pp. 325 - 332
• Main Authors: Ishiguro, K., Baba, E., Torii, R., Tamada, H., Kawate, N., Hatoya, S., Wijewardana, V., Kumagai, D., Sugiura, K., Sawada, T., Inaba, T.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.03.2007
• Subjects: Animals; bacterial adhesion; Bacterial Adhesion - physiology; bioassays; diestrus; Dog; dog diseases; dogs; Dogs - genetics; Dogs - microbiology; Dogs - physiology; epithelial cells; Escherichia coli; Escherichia coli - physiology; Escherichia infections; Estrus - metabolism; Female; gene expression; Gene Expression Regulation; genes; in vitro studies; microbial genetics; Muc1; mucin-1 gene; Mucins - genetics; Mucins - metabolism; pathogenicity; Pyometra; Uterine Diseases - metabolism; Uterine Diseases - microbiology; Uterine Diseases - veterinary; Uterus; Uterus - metabolism; Uterus - microbiology; Muc1; Uterus; Pyometra; Dog; Escherichia coli
• ISSN: 1090-0233; 1532-2971
• DOI: 10.1016/j.tvjl.2005.11.009

The relation between adherence of Escherichia coli and expression of mucin-1 (Muc1: an integral membrane mucin) mRNA in the endometrium was studied in beagle bitches at different stages of the oestrous cycle and in those with cystic endometrial hyperplasia/pyometra complex (pyometra). The number of E. coli adhering to the endometrium was low at pro-oestrus and oestrus and increased at the early stage (day 10) of dioestrus, corresponding to the implantation period; it declined thereafter. Adhesion of the organisms to endometrial epithelial cells collected at day 10 of dioestrus was inhibited by the addition of d-mannose. When endometrial epithelial cells collected at pro-oestrus were treated with hyaluronidase, an enzyme that digests mucins, the numbers of E. coli adhering to the cells tended to increase. With polymerase chain reaction analysis it was possible to detect Muc1 gene transcripts in the endometrium at all stages of the oestrous cycle, although the level of Muc1 mRNA decreased by day 10 of dioestrus. The levels of Muc1 mRNA in bitches with a clinical stage of pyometra were low and comparable to those at day 10 of dioestrus. The number of E. coli adhering to the endometrium and Muc1 mRNA levels in the endometrium were inversely correlated ( r = −0.77, P < 0.01). Immunohistochemical analysis showed little staining for Muc1 in the endometrial epithelia at day 10 of dioestrus and in bitches with pyometra. These results suggest that reduction of Muc1 expression is associated with increased E. coli adherence in the canine uterus at the early stage of dioestrus, possibly facilitating the development of pyometra.