ABSTRACT
Objective To investigate the effect of Spry1 on adipocyte differentiation from ST2 cells by using siRNA. Methods Synthesized siRNA targeting Spry1 was used as experimental group, and control siRNA was used as control group. Spry1 siRNA and control siRNA were transfected into ST2 cells, then treating with adipogenic medium to induce adipocyte differentiation. The mRNA expression levels of Spry1 and adipocyte differentiation-specific genes PPARγ(peroxisome proliferator-activated receptor gamma), C/EBP α (CCAAT enhancer binding protein α), FABP4 (adipocyte marker gene fatty acid binding protein 4) and adipsin were examined by quantitative real-time PCR. The mature adipocytes were stained with oil red O, the staining adipocytes were observed by microscope, then understanding the effect of Spry 1 siRNA on adipocyte differentiation. In addition, oil red O of the staining adipocytes was extracted with isopropanol, optical density (OD) values of oil red O were measured at a wavelength of 520 nm. Results Spry1 siRNA was transfected into ST2 cells. Compared with control group, the mRNA expression level of Spry1 was significantly reduced. The number of differentiated adipocytes from ST2 cells was decreased after staining with oil red O. And the OD value was lower than that of control group. The mRNA expression levels of adipocyte differentiation-specific genes PPARγ, C/EBP α, FABP4 and adipsin were significantly reduced compared with those of control group (P<0.05). Conclusion Spry1 siRNA can effectively suppresse adipogenic differentiation from progenitor cells.
ABSTRACT
For human beings and animals, the observer encounters the so-called optic flow during locomotion, the image motion pattern of the environment on the retina, which includes three basic modes of motion: rotation, expansion/contraction and translation. The analysis of optic flow information is vital for determining the direction and velocity of locomotion and has been a hotspot of the studies on visual information processing in recent years. In this article, some progresses in psychophysics and electrophysiology studies on optic flow are introduced and the neural mechanism of optic flow processing in mammalian brain is discussed.
