Bisphenol A in combination with insulin can accelerate the conversion of 3T3-L1 fibroblasts to adipocytes

• Published in: Journal of lipid research 2002-05, Vol.43 (5), p.676-684
• Main Authors: Masuno, Hiroshi, Kidani, Teruki, Sekiya, Keizo, Sakayama, Kenshi, Shiosaka, Takahiko, Yamamoto, Haruyasu, Honda, Katsuhisa
• Format: Article
• Language: English
• Subjects: 3T3 Cells; 3T3-L1 adipocytes; Adipocytes - cytology; Adipocytes - drug effects; Adipocytes - physiology; Animals; Benzhydryl Compounds; Cell Differentiation - drug effects; DNA - biosynthesis; environmental endocrine disrupting chemical; Estrogens, Non-Steroidal - pharmacology; Fibroblasts - cytology; Fibroblasts - drug effects; Fibroblasts - physiology; glycerol-3-phosphate dehydrogenase; Glycerolphosphate Dehydrogenase - metabolism; Insulin - pharmacology; lipoprotein lipase; Lipoprotein Lipase - metabolism; Mice; Phenols - pharmacology; Proliferating Cell Nuclear Antigen - analysis; Thymidine - metabolism; triacylglycerol accumulation; Triglycerides - metabolism
• ISSN: 0022-2275
• DOI: 10.1016/S0022-2275(20)30108-5

The confluent cultures of 3T3-L1 fibroblasts were treated with or without bisphenol A (BPA) for 2 days and subsequently treated with insulin (INS) alone for 9 days. When BPA was absent during the first 2-day treatment period, the cultures contained 1.6 microg/microg DNA of triacylglycerol (TG), 202 mU/mg DNA of lipoprotein lipase (LPL) activity, and 462 nmol/min/mg DNA of glycerol-3-phosphate dehydrogenase (GPDH) activity. The presence of BPA during the same period caused a 150% increase in the TG content, a 60% increase in the LPL activity, and a 500% increase in the GPDH activity. Thus, BPA by itself can trigger 3T3-L1 fibroblasts to differentiate into adipocytes. Next, the confluent cultures were treated with BPA for 2 days and subsequently treated with a combination of INS and BPA for 9 days. The simultaneous presence of BPA with INS caused a 370% increase in the TG content, a 200% increase in the LPL activity, and a 225% increase in the GPDH activity compared with the cultures treated with INS alone. The amount of [(3)H]thymidine incorporated into DNA was lower in the cultures treated with INS in the presence of BPA than in those treated with INS alone, indicating that BPA has an anti-proliferative activity on 3T3-L1 cells. Taken together, our results indicate that BPA in combination with INS can accelerate the adipocyte conversion.