Effect of Recombinant Netrin-1 Protein Combined with Peripheral Blood Mesenchymal Stem Cells on Angiogenesis in Rats with Arteriosclerosis Obliterans

Abstract

This work was aimed to explore the effect of recombinant netrin-1 protein and peripheral blood mesenchymal stem cells (MSCs) on the angiogenesis ability of atherosclerosis. 28 Sprague Dawley (SD) rats were taken as research models. The arterial occlusion models were created by surgery and then divided into the saline control group ( $n$  =7), netrin-1 treatment group ( $n$  =7), MSCs treatment group ( $n$  =7), and netrin-1 + MSCs combined treatment group ( $n$  =7). The peripheral blood MSCs were extracted from the peritoneal cavity of diseased SD rats and cultured alone or in combination with netrin-1. The individually cultured MSCs and netrin-1 were locally injected into the ischemic tissues of SD rats. The Tarlov scoring was performed at the first, second, and third week of treatment, respectively. The expression of vascular endothelial growth factor (VEGF) was also measured by quantitative real-time polymerase chain reaction (qRT-PCR), and the capillary density was measured by immunofluorescence staining. The mean maximum contractility of the gastrocnemius muscle in each group was determined in the third week after treatment. The Tarlov score of the netrin-1 + MSCs group was significantly higher than that of the control group ( $P<0.05$ ) at the second week. To the 4th week of treatment, the Tarlov score of the netrin-1 + MSCs group was highly increased compared to the netrin-1 group and the MSCs group ( $P<0.05$ ). The expression of VEGF in the treatment groups was greatly increased each week compared to the control group ( $P<0.05$ ). Compared with the netrin-1 and the MSCs groups, the VEGF was also notably increased in the netrin-1 + MSCs group (P <0.05). The capillary densities of the treatment groups were observably greater than that of the control group in the second and third weeks (P <0.05), while the capillary density in the netrin-1 + MSCs group was also significantly increased than those in the netrin-1 group and the MSCs group ( $P<0.05$ ). The mean maximum contractility of the netrin-1 + MSCs group was remarkably higher than that of the other groups ( $P<0.05$ ). The netrin-1 + MSCs group achieved the higher Tarlov score, higher VEGF expression, higher capillary density, and better muscle recovery than netrin-1 and MSCs treatments.