Expression and function of vascular endothelial growth inhibitor in aged porcine bladder detrusor muscle cells

• DOI: 10.1007/s10522-013-9460-5
• Publication Date: 2013-09-12T14:56:46Z
• Authors: Mingqing Wang; Ning Zhang; Wei Wang; Biao Wang; Zhiqing Xu; Yong Yang
• Keywords: Tumor Necrosis Factor Ligand Superfamily Member 15; 0303 health sciences; Base Sequence; Swine; Urinary Bladder; Age Factors; Fluorescent Antibody Technique; Muscle, Smooth; Real-Time Polymerase Chain Reaction; 03 medical and health sciences; Animals; Female; Cells, Cultured; DNA Primers

Aging of the bladder detrusor muscle plays an important role in lower urinary tract symptoms in elderly people. Our previous work demonstrated that elderly patients have increased levels of vascular endothelial growth inhibitor (VEGI) in bladder tissue. Therefore, we hypothesized that VEGI may play a role in aging of the bladder detrusor muscle cells. This study aims to develop and characterize primary cultures of aged porcine bladder detrusor muscle cells in order to explore the expression and function of VEGI. Bladder samples from female pigs were divided into two groups: the aged group (Model) and the young group (Control). We confirmed β-galactosidase expression, a marker for senescence, in aged muscle cells (identified by α-smooth muscle actin (α-SMA) staining), but not in the young group. mRNA levels of VEGI-251 and death receptor 3 (DR3) were up-regulated (P < 0.05) and total cell protein levels of VEGI-251, DR3 and nuclear factor-kappa B [NF-κB (p65)], membrane protein levels of DR3, and nuclear protein levels of NF-κB (p65) were significantly higher (P < 0.01) in the Model cells compared to Control cells. In conclusion, we have established a method to culture aged detrusor muscle cells derived from porcine bladder. Higher levels of VEGI-251, DR3 and NF-κB (p65) were observed in the aged cells. VEGI-251 may function by increasing DR3 on cellular membranes and promoting the transfer of NF-κB into the nucleus. This suggests that VEGI may be a target for reversing the aging process of bladder detrusor muscle cells.