Abstract
Visfatin was originally identified as a growth factor for immature B cells, and recently demonstrated to bind insulin receptor. Visfatin mRNA and protein were detected by RT-PCR and Western blot analysis in cloned bovine mammary epithelial cells, lactating bovine mammary gland and human breast cancer cell line, MCF-7. Immunocytochemical staining localized the visfatin protein in the cytosol and nucleus of both cells. Quantitative-RT-PCR analysis revealed that the expression of the visfatin mRNA was significantly elevated when treated with forskolin (500 microM), isopreterenol (1-10 microM) and dibutyric cyclic AMP (1 mM) for 24 h, and significantly reduced when treated with insulin (5-50 ng/ml) and dexsamethasone (0.5-250 nM) for 24 h. These results indicate that mammary epithelial cells express the visfatin protein and secrete them into the milk.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
5' Flanking Region / genetics
-
Activating Transcription Factor 2 / genetics
-
Amino Acid Sequence
-
Animals
-
Base Sequence
-
Cattle
-
Cyclic AMP / metabolism*
-
Cyclic AMP Response Element-Binding Protein / genetics
-
Cytokines / chemistry
-
Cytokines / genetics*
-
Cytokines / metabolism*
-
Cytosol / metabolism
-
Dexamethasone / pharmacology
-
Epithelial Cells / cytology*
-
Epithelial Cells / drug effects
-
Female
-
Humans
-
Insulin / pharmacology
-
Lactation / drug effects
-
Lactation / metabolism*
-
Mammary Glands, Animal / cytology*
-
Mammary Glands, Animal / drug effects
-
Milk / chemistry*
-
Molecular Sequence Data
-
Oxytocin / pharmacology
-
Protein Transport / drug effects
-
RNA, Messenger / genetics
-
RNA, Messenger / metabolism
-
Sequence Alignment
-
Up-Regulation / drug effects
Substances
-
Activating Transcription Factor 2
-
Cyclic AMP Response Element-Binding Protein
-
Cytokines
-
Insulin
-
RNA, Messenger
-
Oxytocin
-
Dexamethasone
-
Cyclic AMP