Effects of transplanting autologous bone marrow mesenchymal stem cells via articular cavity on skeletal fluorosis rabbits

Abstract

Objective To observe the efficacy and feasibility of transplanting autologous bone marrow mesenchymal stem cells (BMSCs) via articular cavity on skeletal fluorosis rabbits. Methods A total of 30 rabbits, half male and half female, were divided into control group (n = 6) and experimental group (n = 24) by random number table method. The two groups of rabbits were given drinking water containing NaF 0 or 300 mg/L, respectively. After 90 days, 24 rabbits were divided into single treatment group, multiple treatment group, spontaneous recovery group and treatment solvent control group (6 rabbits in each group, half male and half female). After isolation, the BMSCs from skeletal fluorosis rabbits were cultured and identified, autologous BMSCs were transplanted into rabbit bodies via articular cavity at once or at three different other times, respectively. After 60 days, femur image was observed through X-ray. Femur bone mineral density was measured with quantitative CT (QCT). Serum alkaline phosphatase (ALP) and osteocalcin (BGP) were also measured using enzyme linked immunosorbent assay (ELISA). Bone fluoride content was determined via the fluorine ion-selective electrode method. Histopathology changes of femur were observed through HE staining and the trabecular area was calculated. Results In the multiple treatment group, patchy high-density images of femur were disappeared and abnormal bone texture was recovered compared with that of before transplantation. Bone density [(536.91 ± 25.51) g/cm3], ALP concentration [(20.06 ± 6.25) U/L], BGP concentration [(1 230.01 ± 119.50) μg/L], bone fluoride content [(1 442.40 ± 458.54) mg/kg] and trabecular area [(27.81 ± 2.90) Tb.Ar] of the multiple treatment group were lower than those of spontaneous recovery group [(635.11 ± 93.42) g/cm3, (43.08 ± 2.82) U/L, (3 207.73 ± 788.80) μg/L, (2 557.65 ± 173.90) mg/kg, (38.52 ± 2.81) Tb.Ar], and the differences were statistically significant (P < 0.05). HE staining in the multiple treatment group showed that bone marrow cavity was enlarged, and the number of trabeculae was decreased, accompanied by some new generated, neatly arranged normal trabeculae. But similar results were not observed in the single treatment group. Conclusion After multiple transplantation via articular cavity, autologous BMSCs from skeletal fluorosis rabbits could repair the damaged bone tissue and improve the pathological damage of skeletal fluorosis with osteosclerosis. Key words: Transplantation; Skeletal fluorosis; Rabbit; Bone marrow mesenchymal stem cells