Butyrylation Of Adipocyte Protein In Obesity

BackgroundIn recent years,the increased prevelance in obesity,and related metabolic diseases has become one of the main medical problems in the world.Many studies have shown that adipose tissue expansion is a result of increase in the number of adipocytes and increase in the volume of adipocytes.Post-translational modifications(PTMs)is a major mechanism in the regulation of protein function,which stands as one of the major goals of postgenomics biological research.PTMs affect the subcellular distribution,protein-protein interaction,and biological activity of proteins.Recently,butyrylation has been found as a new type of PTMs,which is a result of attachment of a butyric acid group to the lysine residue of a protein.The butyrylation has beed reported in cell differentiation such as sperm development,and cellular changes in some diseases.However,the role of butyrylation remains unknown in adipocyte differentiation and development of obesity.ObjectiveExplore the relationship of butyrylation an adipogenesis to understand its role in obesity.Methods1.Establishment of animal model: the 6-week-old C57BL/6 mice are divided into two groups,chow diet and high fat diet(HFD).Fat samples were collected and examined at 1,5 and 10 weeks on HFD.2.Body weight: mouse body weight was examined every week durng the HFD feeding.3.Western blot(WB): Butyrylation was examined in mouse epididymal adipose tissue and 3T3-L1 adipocytes with WB;4.Oil red O staining: Lipid droplets were determined in differentiated 3T3-L1 adipocytes with oil red O staining.Results1.The mouse body weight was increased on HFD with expansion of epididymal adipose tissue.2.The butyrylation signal was increased in the epididymal adipose tissue of mice on HFD,but there is no difference in acetylation.The butyrylation was not changed in mice on chow diet.3.Oil red O staining results showed that the lipid droplets were observed in 3T3-L1 Cells on day 6 of differentiation in the inducer II and the accumulation of lipid droplets was increased with the time thereafter.4.Western blot indicated that the expression of butyrylation and acetylation were gradually increased during the differentiation process of 3T3-L1 cells.5.In mature 3T3-L1 adipocytes,Forskolin treatment led to a reduction in the expression of butyrylation and acetylation.Conclusion Butyrylation may be required for adipocyte differentiation and adipose tissue expansion.