The role of syndecan-4 and underlying mechanisms in dorsal root ganglion mechanotransduction using controlled polydimethylsiloxane substrate stiffness

• Main Authors: Tzu-Jou Lin, 林子柔
• Other Authors: Chien-Yun Hsiang
• Format: Others
• Language: en_US
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/ru6gm5

碩士 === 中國醫藥大學 === 基礎醫學研究所碩士班 === 101 === Mechanotransduction, the mechanical stimuli are transformed into a biological response, organize the physiological processes, such as senses of touch, hearing, makes an essential contribution to homeostasis. In mammals, the detection of mechanical forces is transduced by trigeminal ganglia (TG) or dorsal root ganglia (DRG) neurons. The syndecans (SDCs) are one of the adhesion receptor families that modulate the adhesion and as organizers of the extracellular matrix (ECM), there are four types of the syndecans family in mammals, and the syndecan-4 (SDC-4) can signal to cause focal-adhesion formation and migration by increasing protein kinase Cα (PKCα) activation. In previous study, PKCα and focal adhesion kinase (FAK) are regulated by syndecan-4, but the mechanism and role of SDC-4 in DRG neurons remain obscure. Thus, we harvested the DRG neurons from mice, and culturing DRGs on controlled polydimethylsiloxane (PDMS) substrates (PDMS ratio of base to curing agent of 35:1) coating with poly-L-lysine (poly) or FN to investigate the mechanisms of mechanotransduction using DRG neurons. Our results determine the signal pathways were through pPKCα- pFAK- pERK activation. In this study, we use western blot (WB) and immunofluorescent staining (IF) to observe the SDC-4 protein express in DRG neurons, and had no significance between soma and fiber. We then seeded the DRGs on the different substrates coated with poly-L-lysine or FN, and use the IF to observed neuron morphology, this data suggested that FN may participate in DRGs density, neurite length and branch. Finally, we use WB to compare the DRGs proteins expression after stretch PDMS membrane to investigate the mechanisms of mechanotransduction. In previous study indicated that FAK had high relation with neurite outgrowth, thus, our data showed that pPKCα、FAK p Tyr397 and pERK1/2 proteins level significant increase in the each stretch group may through SDC-4.