BACKGROUND: Bone morphogenetic protein in combination with hol ow porous titanium al oy can improve the affinity with surrounding bone tissues. OBJECTIVE: To observe the effects of bone morphogenetic protein 2 on growth and osteogenic differentiation of bone marrow mesenchymal stem cel s cuftured on a hol ow porous metal prosthesis scaffold. METHODS: Passage 3 Sprague-Dawley rat bone marrow mesenchymal stem cel s were directly inoculated onto a hol ow porous metal prosthesis, and then the scaffold was cultured in DMEM medium containing 0, 0.001, 0.01, 0.06 and 0.1 g/L bone morphogenetic protein 2, respectively. At 6, 12, 24 and 48 hours after inoculation, cel adhesion was detected by MTT assay. Cel osteogenic differentiation was detected by alizarin red staining at 18 days. Besides, Transwel culture was put on the scaffold, and 5x108/L bone marrow mesenchymal stem cel s were added into the upper chamber, and DMEM medium containing 0, 0.001, 0.01, 0.06 and 0.1 g/L bone morphogenetic protein 2 were added into the lower chamber to observe cel migration capability after 0, 6, 12, 24 and 48 hours culture. RESULTS AND CONCLUSION: After 6-48 hours of inoculation, different mass concentrations of bone morphogenetic protein 2 promoted adhesion of bone marrow mesenchymal stem cells in a time-dependent manner. After 18 days of inoculation, bone marrow mesenchymal stem cells induced by different mass concentrations of bone morphogenetic protein 2 changed from fusiform to polygon, and arranged in a multilayer and overlapped form. Numerous calcified nodules could be found, which were stained red by alizarin red. Additionally, within 6-48 hours of culture, bone morphogenetic protein 2 could promote the migration of bone marrow mesenchymal stem cells in a concentration-and time-dependent manner. In conclusion, bone morphogenetic protein 2 can enhance the adhesion, osteogenic differentiation and migration of bone marrow mesenchymal stem cells cultured on the hollow porous metal prosthesis.

Objective To observe the effect of JLP on transdifferentiation of human renal proximal tubular epithelial cells (HK-2),and to investigate the role of p38 MAPK signaling pathway in this process.Methods The knock-down plasmids of JLP were constructed.HK-2 cells were randomly divided into four groups:negative control cells (Ctrl-shRNA group),knock-down jlp cells (jlpshRNA group),negative control cells with FGF-2 treatment (FGF-2 group) and knock-down jlp cells with FGF-2 treatment(jlp-shRNA +FGF-2 group).The expressions of JLP,E-cadherin,TGF-β1,α-SMA,p-p38 MAPK protein were detected by Western blotting.After the induction of FGF-2 for 24 hours,the expressions of α-SMA,COL-Ⅰ,FN were detected by immunocytochemistry.Results Compared with Ctrl-shRNA group,the expression of JLP protein was significantly down-regulated in FGF-2 group.Compared with FGF-2 group,the expressions of TGF-β1,α-SMA,p-p38 MAPK protein were significantly up-regulated,while E-cadherin protein was significantly down-regulated (P ＜ 0.05).Compared with FGF-2 group,the expressions of α-SMA,COL-Ⅰ,FN immunostaining increased markedly in jlp-shRNA+FGF-2 group.Conclusion Scaffolding protein JLP is critical in preventing EMT in the course of fibrosis through the inhibition of p-p38 activation in HK-2 cells.

Objective To observe the effect of JLP deficiency on the progression of renal interstitial fibrosis in mice model of unilateral ureteral obstruction (UUO),and to investigate the role and underlying mechanism of JLP in the development of renal fibrosis in obstructive nephropathy.Methods jlp Wild type (jlp+/+) and jlp deficient (jlp-/-) mice were divided into four groups:jlp+/+-and jlp-/--sham-operated groups(jlp-/--sham group and jlp+/+-sham group),jlp+/+-and jlp-/--unilateral ureteral obstruction (UUO)-operated groups (jlp/--UUO group and jlp+/+-UUO group).Mice were sacrificed at 7 days and 14 days after the operation respectively to evaluate the fibrosis by Masson staining.The expression of JLP in jlp +/+ renal tissue was assayed by immunohistochemistry staining,immunofluorescence and Western blotting.Immunohistochemical staining was used to detect the expression of α-smooth muscle actin (α-SMA),collagen Ⅰ (COL-Ⅰ),collagen Ⅲ (COL-Ⅲ) and transforming growth factor-β1 (TGF-β1) in sham and UUO groups.Besides,the α-SMA,COL-Ⅰ,COL-Ⅲ,TGF-β1,p-Smad2 and p-Smad3 protein levels were also analyzed by Western blotting in four groups.Results The expression of JLP was mainly demonstrated in the renal tubules of mice.A large amount of collagen deposition was observed in the renal interstitial area in jlp-/--UUO group compared to jlp+/+-UUO group.Similarly,the expression of α-SMA,COL-Ⅰ,COL-Ⅲ and TGF-β1 was significantly increased in the kidney cortices in jlp-/--UUO-operated groups.Meanwhile,Western blotting showed that the expression of α-SMA,COL-Ⅰ,COL-Ⅲ,and TGF-β1 protein was obviously higher in jlp-/--UUO group.Moreover,the expression of p-Smad2 and p-Smad3 protein was markedly higher in jlp-/--UUO group.Conclusion Scaffolding protein JLP is critical in preventing renal fibrosis through the inhibition of TGF-β1 expression and myo-fibroblast production.

Objective:To prepare PEG-SH modified GNPs/miR-29 nanoparticles and to investigate the proliferation and differentiation of neural stem cells induced by PEG-SH modified GNPs/miR-29 nanoparticles.Methods:PEG-SH modified GNPs/miR-29 nanoparticles were developed by oxidation-reduction method and were tested for UV absorption spectrum, particle size distribution and zeta potential of nanoparticles. A total of 15 adult male Sprague Dawley (SD) rats were used to establish spinal cord injury model by modified Allen method. The artificial miR-29 and PEG-SH modified GNPs/miR-29 nanoparticles were implanted into the injury site of spinal cord respectively. The stability of miR-29 expression was analyzed by gel electrophoresis. The neural stem cells were isolated and cultured from 10 SPF grade neonatal rats. It was identified by Nestin, GFAP and NSE antibodies. The activity and proliferation of neural stem cells in synthetic miR-29, PEG-SH GNPs and PEG-SH GNPs/miR-29 nanoparticles group was detected by CCK-8 assay. Neural stem cells were cultured with synthetic miR-29, PEG-SH GNPs and PEG-SH GNPs/miR-29 nanoparticles for 1 week. The density, length and number of neuritis were investigated.Results:The solution of PEG-SH modified GNPs showed a brownish red appearance. The spheres were in uniform distribution under transmission electron microscope. The results of UV absorption spectrum showed a single peak wave. The peak value of UV absorption was near 523 nm. The zeta potential increased gradually with the increased content of PEG-SH. The peak value of zeta potential was 22.5±5.2 mV. With the increase of content of PEG, the particle size of PEG-SH modified GNPs rapidly reached peak value at the early stage and then decreased rapidly to a relatively stable level. The synthetic miR-29 and PEG-SH modified GNPs/miR-29 nanoparticles were implanted into the injury site of spinal cord. At 0-6 h, clear band was observed in the synthetic miR-29 group. However, the band was disappeared rapidly at 12-24 h. In PEG-SH GNPs/miR-29 group, clear band were always observed. The OD values of miR-29 group were 0.34±0.17, 0.78±0.31, 1.28±0.68, 1.64±0.38 at 1, 3, 5 and 7 d after inoculation respectively. There was no significant difference in OD values compared with DMEM group. There was no significant difference in OD values among GNPs, PEG-SH GNPs, PEG-SH GNPs/miR-29 and DMEM group. The density (56.38±3.65 μm 2), length (78.25±3.72 μm) and the number [(356±34.52) /1,000×high power field] of neurites in PEG-SH GNPs/miR-29 group were higher than those in miR-29 group, PEG-SH modified GNPs group and saline group. However, there was no significant difference in the density, length and number of neurite between PEG-SH GNPs/miR-29 and serum group. Conclusion:PEG-SH modified GNPs/miR-29 nanoparticless have good biological properties. It can induce the proliferation and differentiation of neural stem cells with protective effects on miR-29.

Immunoscenescence plays a key role in the initiation and development of tumors. Furthermore, immunoscenescence also impacts drug delivery and cancer therapeutic efficacy. To reduce the impact of immunosenescence on anti-tumor therapy, this experimental plan aimed to use neutrophils with tumor tropism properties to deliver sialic acid (SA)-modified liposomes into the tumor, kill tumor cells via SA-mediated photochemotherapy, enhance infiltration of neutrophils into the tumor, induce immunogenic death of tumor cells with chemotherapy, enhance infiltration of CD8⁺ T cells into the tumor-draining lymph nodes and tumors of immunosenescent mice, and achieve SA-mediated photochemotherapy. We found that CD8⁺ T cell and neutrophil levels in 16-month-old mice were significantly lower than those in 2- and 8-month-old mice; 16-month-old mice exhibited immunosenescence. The anti-tumor efficacy of SA-mediated non-photochemotherapy declined in 16-month-old mice, and tumors recurred after scabbing. SA-mediated photochemotherapy enhanced tumor infiltration by CD8⁺ T cells and neutrophils, induced crusting and regression of tumors in 8-month-old mice, inhibited metastasis and recurrence of tumors and eliminated the immunosenescence-induced decline in antitumor therapeutic efficacy in 16-month-old mice via the light-heat-chemical-immunity conversion.