The Role of Repeat Administration of Adventitial Delivery of Lentivirus-shRNA-Vegf-A in Arteriovenous Fistula to Prevent Venous Stenosis Formation

Abstract

Purpose Previous study has demonstrated that adventitial delivery of lentivirus mediated Vegf-A shRNA (LV-shRNA-Vegf-A, small hairpin RNA that inhibits Vegf-A gene expression) at the time of arteriovenous fistula (AVF) creation increases the lumen vessel area (LVA) of the outflow vein and reduces venous neointimal hyperplasia (VNH). However, the effect of decreasing Vegf-A and improving LVA decreases by 2-weeks as stenosis develops. The aim of the present study was to determine if a second dose of LV-shRNA-Vegf-A could improve LVA and decrease VNH. Methods Chronic kidney disease was created in C57BL/6 mice and 28 days later, a AVF was created by connecting right carotid artery to ipsilateral jugular vein. 5×106 plaque forming units of LV-shRNA-Vegf-A or control shRNA was administered to the adventitia of the outflow vein immediately after AVF creation and a second dose of the same treatment fourteen days later. Animals were sacrificed at 21, 28, and 42 days after AVF creation for reverse transcription polymerase chain reaction (RT-PCR) and histomorphometric analyses. Results By day 21, there was a 25% increase in the average LVA (day 21: P=0.11), with a decrease in cell proliferation (day 21: P=0.0079, day 28: P=0.28; day 42: P=0.5), decrease in α-smooth muscle cell actin staining (day 21: P<0.0001, day 28: P<0.05; day 42: P=0.59), and decrease in hypoxic stress (day 21: P<0.001, day 28: P=0.28; day 42: P=0.46) in LV versus control shRNA vessels, respectively. Conclusion A second dose of LV-shRNA-Vegf-A administration results in a moderate improvement in LVA at day 21.

The Role of MicroRNA-21 in Venous Neointimal Hyperplasia: Implications for Targeting miR-21 for VNH Treatment

“…Mice were anesthetized with a ketamine (100 mg/kg body weight) and xylazine (10 mg/kg body weight) mixture prior to surgery, and nephrectomy was performed to create CKD as described. 10 , 17 , 22 , 23 , 24 The mice undergoing this procedure have been shown to have elevated BUN and creatinine by 3–4 weeks after nephrectomy. 10 , 17 , 22 , 23 , 24 After 28 days of CKD creation, the left carotid artery was connected to the left jugular vein to create an AVF as described.…”

“… 10 , 17 , 22 , 23 , 24 The mice undergoing this procedure have been shown to have elevated BUN and creatinine by 3–4 weeks after nephrectomy. 10 , 17 , 22 , 23 , 24 After 28 days of CKD creation, the left carotid artery was connected to the left jugular vein to create an AVF as described. 22 The outflow vein of the fistula, also referred to as the GV, and the contralateral jugular vein (CV) of the same mouse as the control vein were excised for PCR at days 3 and 7 of fistula creation.…”

“… 10 , 17 , 22 , 23 , 24 After 28 days of CKD creation, the left carotid artery was connected to the left jugular vein to create an AVF as described. 22 The outflow vein of the fistula, also referred to as the GV, and the contralateral jugular vein (CV) of the same mouse as the control vein were excised for PCR at days 3 and 7 of fistula creation. The comparison of change in gene expression in CV and GV at each time point would not only be due to AVF creation but also to avoid the contribution of uremia.…”

“…Vessel lumen area, vessel wall thickness, and intensity of chromogen stain were assessed by Zen-Pro software (Zeiss) as described. 22…”

Notch Signaling in Endothelial Cells: Is It the Therapeutic Target for Vascular Neointimal Hyperplasia?

“…In addition, bone marrow-derived mesenchymal stem cells treated with VEGF differentiate into endothelial-like cells and significantly attenuate neointimal thickness [ 84 ]. However, lentivirus-mediated VEGF-A inhibition can decrease the venous neointimal hyperplasia of AVFs [ 85 ]. This evidence suggested that the effect of VEGF on neointimal formation is complicated.…”