Neural stem cell (NSC) transplantation has been proposed to promote functional recovery after spinal cord injury. However, a detailed understanding of the mechanisms of how NSCs exert their therapeutic plasticity is lacking. We transplanted mouse NSCs into the injured spinal cord seven days after SCI, and the Basso Mouse Scale (BMS) score was performed to assess locomotor function. The anti-inflammatory effects of NSC transplantation was analyzed by immunofluorescence staining of neutrophil and macrophages and the detection of mRNA levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) and interleukin-12 (IL-12). Furthermore, bone marrow-derived macrophages (BMDMs) were co-cultured with NSCs and followed by analyzing the mRNA levels of inducible nitric oxide synthase (iNOS), TNF-α, IL-1β, IL-6 and IL-10 with quantitative real-time PCR. The production of TNF-α and IL-1β by BMDMs was examined using the enzyme-linked immunosorbent assay (ELISA). Transplanted NSCs had significantly increased BMS scores (p < 0.05). Histological results showed that the grafted NSCs migrated from the injection site toward the injured area. NSCs transplantation significantly reduced the number of neutrophils and iNOS+/Mac-2+ cells at the epicenter of the injured area (p < 0.05). Meanwhile, mRNA levels of TNF-α, IL-1β, IL-6 and IL-12 in the NSCs transplantation group were significantly decreased compared to the control group. Furthermore, NSCs inhibited the iNOS expression of BMDMs and the release of inflammatory factors by macrophages in vitro (p < 0.05). These results suggest that NSC transplantation could modulate SCI-induced inflammatory responses and enhance neurological function after SCI via reducing M1 macrophage activation and infiltrating neutrophils. Thus, this study provides a new insight into the mechanisms responsible for the anti-inflammatory effect of NSC transplantation after SCI.

Aim: To investigate whether the aberrant expression of microRNA (miR)-196a and miR-196b can be used as potential prognostic markers of human osteosarcoma. Methods: Quantitative real-time reverse transcriptase-polymerase chain reaction (qRT-PCR) analysis was performed to detect the expression levels of miR-196a and miR-196b in osteosarcoma tissues and patients’ sera. Results: Expression levels of miR-196a and miR-196b in osteosarcoma tissues were both significantly higher than those in noncancerous bone tissues (both p < 0.001), in line with which, the serum levels of the two miRNAs were also markedly upregulated in patients with osteosarcomas compared with healthy controls (both p < 0.001). Then, the elevation of serum miR-196a and miR-196b levels both more frequently occurred in osteosarcoma patients with high tumor grade (p = 0.008 and 0.01, respectively), positive metastasis (p = 0.001 and 0.006, respectively) and recurrence (p = 0.001 and 0.006, respectively). Moreover, high serum miR-196a, high serum miR-196b and conjoined expression of miR-196a/miR-196b were all independent prognostic factors for OS (overall survival) and DFS (disease-free survival) of osteosarcoma patients. Conclusion: Our present data indicate the involvement of miR-196a and miR-196b upregulation in the pathogenesis of osteosarcoma. More importantly, the altered levels of circulating miR-196a and miR-196b might have great potential to serve as novel and non-invasive prognostic factors for this malignancy.