Small Molecular Probe For Preadipocytes Browning

Adipose tissue hypertrophy is one of the obvious symptoms of obesity. Generally, adipose tissues are classified into white adipose tissue (WAT), brown adipose tissue (BAT) and beige adipose tissue (Beige AT).It is known that overweight and obesity are accompanied by reduction in BAT. In recent years,enhancing the function of BAT or the browning of preadipocytes through regulation by microRNAs (miRNAs) was regarded as a potential method to treat obesity. In the muscle tissue, miR-133, has been found to be involved in the regulation of adipocytes differentiation. In this thesis, based on our previous report that a potential bio-active molecular framework was found to inhibit miR-133,we developed small molecular probes through chemical modification and used these probes to investigate their activities in the preadipocyte browning and related detailed mechanisms.In the first part of this thesis, after obtaining the single pure molecule from a pair of diastereoisomers synthesized by photo reaction, we developed them into small molecular probes bearing alkyne moiety for following click reaction and diazirine moiety for photo-crosslinking. We found that c9-endo and c10-endo could significantly inhibit the expression level of miR-133 in C2C12 cells.In the second part of this thesis, we investigated the biological function of c9-endo and c10-endo. We found that they could promote the browning of preadipocytes and increase the mRNA level of PRDM16 and beige-selective genes including Tmem26, CD 137, Tbxl. In the third part of this thesis, to explore their intracellar targets with these small molecular probes, we optimized click reaction conditions, including optimizing the ratio of two substrates, the ratio of copper catalyst and ligands or pH of reaction buffer. We finally found an ideal condition for further biotinylation of small molecular probes through click reaction. Target identification with these probes are still inderway in our group.