Life Sciences Commons^™

Role Of C-Kit Receptor Tyrosine Kinase On Ins-1 Cell Vegf-A Expression In Vitro, Alexei Popell

Electronic Thesis and Dissertation Repository

Interactions between Stem Cell Factor (SCF) and c-Kit are critical in maintaining β-cell survival and function. VEGF-A, essential in facilitating islet vasculature formation, is secreted by β-cells. This work investigates the mechanisms by which c-Kit regulates VEGF-A production in β-cells, using a rat insulinoma (INS-1) cell line as an in vitro model. Cells were treated with recombinant hSCF or cultured with c-Kit (r) siRNA for 72 h. VEGF-A accumulation in the culture medium was measured by ELISA, while qRT-PCR, western blot, and immunofluorescence analyses were also performed. SCF augmented VEGF-A production in a time-dependent (p < 0.05 vs. control at 6 h and 24 h), and dose-dependent manner (p < 0.01 vs. control at 30-100 ng/mL). SCF stimulation increased phosphorylation of proteins along the PI3K/Akt/mTOR pathway (p < 0.05 vs. control groups), and decreased phosphorylation following siRNA treatment. Our results indicate that c-Kit exerts a regulatory effect on VEGF-A production in β-cells.

The Role Of C-Kit Receptor Tyrosine Kinase In Beta-Cell Proliferation, Function And Survival, Zhi Chao Feng

Electronic Thesis and Dissertation Repository

c-Kit, a receptor tyrosine kinase, interacts with Stem Cell Factor (SCF), mediating cell differentiation, function, and survival. c-Kit is critical for the development and maintenance of beta-cell function in both rodents and humans. The mutation of c-Kit at W locus (c-Kit^Wv/+) in mice results in an early onset of diabetes. However, the underlying mechanisms by which c-Kit deficiency leads to beta-cell failure are unknown. Therefore, studying SCF/c-Kit downstream signaling pathways is essential to understanding the precise mechanism by which c-Kit regulates beta-cell survival and function in vivo.

We identified that dysregulated Akt/Glycogen synthase kinase 3β (Gsk3β)/cyclin …