Effect of bone marrow stromal cells on lower urinary tract function of rats with complete spinal cord injury / 中华器官移植杂志

ABSTRACT

Objective To determine whether intravenously transplanted bone marrow stromal cells (BMSCs) could promote recovery of lower urinary tract function in rats with spinal cord transaction.Method The BMSCs were harvested from rats and labeled with 5-bromo-2'-deoxyuridine (BrdU) (30 g/mL) in vitro for 3 days for intravenous transplantation.The BMSCs of 5th passage were characterized by flow cytometry of CD45 and CD90.Twenty-four male Sprague-Dawley rats were divided randomly into three goups.Sixteen rats received a spinal cord transection and a transplantation of cell culture medium (OP-controls,n =8) or BMSCs (n =8).Eight rats were justly given T8-T9 laminectomy (CNS-intact group,n =8).Urodynamic tests,HE staining and immunohistochemistry of the spinal cord with anti-BrdU at 28th day after transplantation were performed.Result The cultured BMSCs of 5th passage expressed 5.94％ of CD45 and 99.4％ of CD90 on flow cytometry.BMSC rats showed significant decrease in residual urine volume (0.85 ± 0.16 mL vs.1.54 ± 0.66 mL,P＜ 0.05),leak point pressure (33.85 ± 3.73 mmHg vs.40.83 ± 3.85 mmHg,P＜0.01),episodes of non-inhibitory contraction (NVC) (2.17 ± 1.12 vs.9.71 ± 3.84,P＜0.01) and increase in voiding efficiency (26.37 ± 6.97％ vs.2.68 ± 1.47,P＜0.01) compared to OP-control rats.In OP-control rats,only tonic EUS activity was remained and busting EUS activity was abolished during bladder filling.While,the tonic EUS activity and busting EUS activity were remained in BMSCs rats.Otherwise,the silent period between EUS bursts was shorter in BMSCs rats (68.86 ± 13.78 ms,P＜ 0.05) and OP-control rats (33.4 ms) than CNS-intact rats (132.79 ± 17.11 ms).Cells derived from BMSCs,identified by 5-BrdU immunoreactivity,survived and were distributed at the damaged tissue (T10),lumbar and sacral spinal cord.Conclusion Intravenously transplanted BMSCs survived in the injured spinal cord,lumbar and sacral cord for rebuilding new voiding reflex and inhibiting afferent sprouting leading to baldder dysfunction.So they had beneficial effects on the recovery of lower urinary tract function in rats with spinal cord transection.