Mouse mammary epithelium produces a soluble heat-sensitive macromolecule that inhibits differentiation of 3T3-L1 preadipocytes.
Coculture of normal mouse mammary gland (NMMG) epithelial cells with 3T3-L1 preadipocytes resulted in inhibition of triglyceride accumulation. This inhibition was also observed when the NMMG cells were grown in inserts and placed within a 100-mm dish containing confluent 3T3-L1 cells. As the number of NMMG-containing inserts was increased, there was a progressive decline in triglyceride content of the 3T3-L1 cells. Conditioned medium from NMMG cells also resulted in a dose-dependent inhibition of adipocyte formation, and when concentrated 10-fold by passage through a filter with a cutoff of 30 kDa, all of the inhibitory activity was recovered. Heating the concentrated conditioned medium at 98 degrees C for 30 min resulted in complete loss of activity. Of several peptides tested, transforming growth factor-beta, platelet-derived growth factor, tumor necrosis factor, interleukin 6, and basic fibroblast growth factor showed inhibitory activity, whereas epidermal growth factor, insulin-like growth factor I, and transforming growth factor-alpha did not.
Calvo
J C
JC
Laboratory of Theoretical and Physical Biology, National Institutes of Health, National Institute of Child Health and Human Development, Bethesda, Maryland 20892.
Chernick
S
S
Rodbard
D
D
D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000273:Adipose Tissue / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects*; D002460:Cell Line; D003470:Culture Media; D003907:Dexamethasone / Q000494:pharmacology; D004848:Epithelium / Q000378:metabolism; D005260:Female; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D007328:Insulin / Q000494:pharmacology; D015850:Interleukin-6 / Q000494:pharmacology; D008321:Mammary Glands, Animal / Q000378:metabolism*; D051379:Mice; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology; D014176:Protein Biosynthesis; D011506:Proteins / Q000494:pharmacology*; D014280:Triglycerides / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D003470:Culture Media; D007328:Insulin; D015850:Interleukin-6; D010982:Platelet-Derived Growth Factor; D011506:Proteins; D014280:Triglycerides; D014409:Tumor Necrosis Factor-alpha; D016222:Fibroblast Growth Factor 2; D003907:Dexamethasone; D015056:1-Methyl-3-isobutylxanthine