Inhibition of preadipocyte differentiation by myostatin treatment in 3T3-L1 cultures.
Myostatin, a new TGF-beta family member, is known as a muscle growth inhibitor, but its role in adipocyte development has not been studied. To test the role of Myostatin in 3T3-L1 preadipocyte differentiation, we treated cultured 3T3-L1 preadipocytes with Myostatin dissolved in 0.1% trifluoroacetic acid (TFA) during differentiation after they had become confluent. Myostatin treatment significantly decreased glycerol-3-phosphate dehydrogenase (GPDH) activity and oil Red-O staining compared to controls that did not receive Myostatin. Western blot analysis showed that the expression levels of CCAAT/enhancer binding protein alpha (C/EBP alpha) and peroxisome proliferator-activated receptor gamma (PPAR gamma) were significantly decreased by Myostatin treatment (P < 0.05). However, the expression of C/EBP beta was not significantly changed by the treatment (P > 0.05). From RT-PCR result, the relative level of leptin mRNA in Myostatin-treated cells was not significantly different (P > 0.1) from the level in cells without Myostatin treatment. Our data show that Myostatin, a secreted protein from muscle, inhibits preadipocyte differentiation in 3T3-L1 cells, which is mediated, in part, by altered regulation of C/EBP alpha and PPAR gamma.
Kim
H S
HS
Department of Animal and Dairy Science, University of Georgia, Athens, Georgia 30602, USA.
Liang
L
L
Dean
R G
RG
Hausman
D B
DB
Hartzell
D L
DL
Baile
C A
CA
D016475:3T3 Cells; D017667:Adipocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D022763:CCAAT-Enhancer-Binding Protein-alpha / Q000235:genetics / Q000378:metabolism; D022782:CCAAT-Enhancer-Binding Protein-beta / Q000235:genetics / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects*; D005786:Gene Expression Regulation / Q000187:drug effects; D005993:Glycerolphosphate Dehydrogenase / Q000187:drug effects / Q000378:metabolism; D020738:Leptin / Q000235:genetics; D051379:Mice; D055435:Myostatin; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014157:Transcription Factors / Q000235:genetics; D016212:Transforming Growth Factor beta / Q000494:pharmacology*
D022763:CCAAT-Enhancer-Binding Protein-alpha; D022782:CCAAT-Enhancer-Binding Protein-beta; D020738:Leptin; C525912:Mstn protein, mouse; D055435:Myostatin; D012333:RNA, Messenger; D018160:Receptors, Cytoplasmic and Nuclear; D014157:Transcription Factors; D016212:Transforming Growth Factor beta; D005993:Glycerolphosphate Dehydrogenase