LncRNAp21 promotes osteogenic differentiation of mesenchymal stem cells in the rat model of osteoporosis by the Wnt/ß-catenin signaling pathway.

OBJECTIVE: The aim of this study was to explore the promoting effect of long non-coding ribonucleic acid p21 (lncRNAp21) on the osteogenic differentiation of mesenchymal stem cells in the rat model of osteoporosis (OP) through the Wnt/ß-catenin signaling pathway. MATERIALS AND METHODS: A total of 30 healthy female rats were selected and randomly divided into three groups, including the lncRNAp21 group, OP model group (model group) and normal group. Rats in the lncRNAp21 group were given a certain quantity of lncRNAp21 inhibitors for gavage. Rats in the model group were regularly given 0.9% NaCl for gavage every day after the removal of bilateral ovaries. Meanwhile, rats in the normal group were fed normally without any changes. Bone mineral density (BMD) was measured after 12 weeks of modeling. The levels of procollagen type I N-terminal propeptide (PINP), serum estradiol (E2), osteocalcin (OC), bone alkaline phosphatase (BALP), C-terminal cross-linking telopeptide of type I collagen (CTX) and tartrate-resistant acid phosphatase 5b (TRACP-5b) in the bone and serum of rats were measured by enzyme-linked immunosorbent assay (ELISA). Besides, quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blotting were adopted to detect the mRNA and protein expressions of Wnt1 and ß-catenin in bone tissues, respectively. RESULTS: Compared with the normal group and lncRNAp21 group, the serum level of E2 in the model group decreased significantly (p<0.05). BMD and phosphorus (P) content in the model group were both markedly lower than those of the normal group and lncRNAp21 group. However, calcium (Ca) content was remarkably higher than that of the normal group and lncRNAp21 group (p<0.05). The serum levels of bone resorption markers (including TRACP-5b and CTX) in the model group were prominently higher than those of the normal group (p<0.05). However, the levels of the two markers in the lncRNAp21 group were significantly lower than the model group (p<0.05). Additionally, bone formation markers (including OC, PINP and BALP) in the serum of rats in the model group were notably higher than those in the normal group and lncRNAp21 group (p<0.05). QRT-PCR and Western blotting results revealed that the mRNA and protein expressions of Wnt1 and ß-catenin in bone tissues of the model group were markedly lower than those of the normal group. However, the mRNA and protein expressions of Wnt1 and ß-catenin in the lncRNAp21 group were remarkably higher than the model group (p<0.05). CONCLUSIONS: Low expression of lncRNAp21 activates the Wnt/ß-catenin signaling pathway by increasing E2 secretion, eventually stimulating bone formation and increasing osteogenic differentiation of mesenchymal stem cells in OP model rats.

Therapeutic effect of transforaminal endoscopic spine system in the treatment of prolapse of lumbar intervertebral disc.

OBJECTIVE: To investigate the clinical efficacy and safety of transforaminal endoscopic spine system (TESSYS) in treating the prolapse of lumbar intervertebral disc. PATIENTS AND METHODS: 462 patients with prolapse of lumbar intervertebral disc who were treated in our hospital from June 2012 to May 2016 were enrolled. All patients were randomly divided into 2 groups: the study group (n=231) and the control group (n=231). Patients in the study group received TESSYS, while those in the control group received conventional surgical treatment with posterior approach. Venous blood was collected before the surgery and 6 h, 12 h, 24 h, and 48 h after surgery. C reactive protein (CRP), interleukin-6 (IL-6), creatine phosphokinase (CPK) and white blood cell (WBC) in each patient were measured. The operation time, intraoperative blood loss, length of stay, postoperative ambulation time and complications were compared between the two groups. Clinical efficacy before and after surgery (1st day, 1st month, 3rd month, and 6th month after surgery) was evaluated according to visual analogue scale (VAS), Oswestry disability index (ODI) and modified MacNab criteria. RESULTS: The operation time, intraoperative blood loss, length of stay, postoperative ambulation time and complications of patients in the study group were less than those of the control group (p<0.05). There were no significant differences in VAS score and ODI score on the 1st day before surgery, 1st day, 1st, 3rd, and 6th month after surgery (p>0.05). According to the improved MacNab standard, the excellent and good rate was 87.88% in the study group and 84.85% in the control group, the difference was not statistically significant (p>0.05). There were no significant differences in CRP, IL-6, CPK and WBC between the two groups before surgery (p>0.05). Postoperative levels of CRP, IL-6, CPK, and WBC in study group were better than those in control group, the differences were statistically significant (p<0.05). CONCLUSIONS: TESSYS has the advantages of less bleeding, less traumatic reactions, fewer complications, rapid postoperative recovery, and exact short-term effect in treatment for prolapse of lumbar intervertebral disc.