SOST,an LNGFR target,inhibits the osteogenic differentiation of rat ectomesenchymal stem cells

Objectives

The aim of this study was to investigate whether sclerostin (SOST) regulates the osteogenic differentiation of rat ectomesenchymal stem cells (EMSCs) and whether SOST and low‐affinity nerve growth factor receptor (LNGFR) regulate the osteogenic differentiation of EMSCs.

Materials and methods

EMSCs were isolated from embryonic facial processes from an embryonic 12.5‐day (E12.5d) pregnant Sprague‐Dawley rat. LNGFR⁺ EMSCs and LNGFR^? EMSCs were obtained by fluorescence‐activated cell sorting and were subsequently induced to undergo osteogenic differentiation in vitro. SOST/LNGFR small‐interfering RNAs and SOST/LNGFR overexpression plasmids were used to transfect EMSCs.

Results

LNGFR⁺ EMSCs displayed a higher osteogenic capacity and lower SOST levels compared with LNGFR^? EMSCs. SOST silencing enhanced the osteogenic differentiation of LNGFR^? EMSCs, while SOST overexpression attenuated the osteogenic differentiation of LNGFR⁺ EMSCs. Moreover, LNGFR was present upstream of SOST and strengthened the osteogenic differentiation of EMSCs by decreasing SOST.

Conclusions

SOST alleviated the osteogenic differentiation of EMSCs, and LNGFR enhanced the osteogenic differentiation of EMSCs by decreasing SOST, suggesting that the LNGFR/SOST pathway may be a novel target for promoting dental tissue regeneration and engineering.

     

The Impact of Device Polarity on the Performance of Polymer–Fullerene Solar Cells

Diketopyrrolopyrrole (DPP)‐conjugated polymers are a versatile class of semiconductors for application in organic solar cells because of their tunable optoelectronic properties. A record power conversion efficiency (PCE) of 9.4% was recently achieved for DPP polymers, but further improvements are required to reach true efficiency limits. Using five DPP polymers with different chemical structures and molecular weights, the device performance of polymer:fullerene solar cells is systematically optimized by considering device polarity, morphology, and light absorption. The polymer solubility is found to have a significant effect on the optimal device polarity. Soluble polymers show a 10–25% increase in PCE in inverted device configurations, while the device performance is independent of device polarity for less soluble DPP derivatives. The difference seems related to the polymer to fullerene weight ratio at the ZnO interface in inverted devices, which is higher for more soluble DPP polymers. Optimization of the nature of the cosolvent to narrow the fibril width of polymers in the blends toward the exciton diffusion length enhances charge generation. Additionally, the use of a retroreflective foil increases absorption of light. Combined, the effects afford a PCE of 9.6%, among the highest for DPP‐based polymer solar cells.     

LncRNA-135528 inhibits tumor progression by up-regulating CXCL10 through the JAK/STAT pathway

Spontaneous tumor regression can be observed in many tumors, however, studies related to the altered expression of lncRNA in spontaneous glioma regression are limited, and the potential contributions of lncRNAs to spontaneous glioma regression remain unknown. To investigate the biological roles of lncRNA-135528 in spontaneous glioma regression. The cDNA fragment of lncRNA-135528 was obtained by rapid-amplification of cDNA ends (RACE) technology and cloned into the plvx-mcmv-zsgreen-puro vector. Additionally, we stably silenced or overexpressed lncRNA-135528 in G422 cells by transfecting with siRNA against lncRNA-135528 or lncRNA-135528 overexpression plasmid. Then, we examined lncRNA-135528 overexpressing and lncRNA-135528 silencing on glioma cells and its effects on CXCL10 and JAK/STAT pathways. The main findings indicated that lncRNA-135528 promoted glioma cell apoptosis, inhibited cell proliferation and arrested cell cycle progression; the up-regulation of lncRNA135528 led to significantly increased CXCL10 levels and the differential expression of mRNA associated with JAK/STAT pathway in glioma cells. lncRNA-135528 can inhibit tumor progression by up-regulating CXCL10 through the JAK/STAT pathway.     

Effect of Cys,GSH, and pH on Mercury Release from Tibetan Medicine Zuotai, β-HgS,and α-HgS in Artificial Gastrointestinal Juices

Biological Trace Element Research - Zuotai, also named as “gTso thal”, a known Tibetan medicinal mixture containing insoluble cubic crystal mercuric sulfide (β-HgS), has been used...     

Biology and life history of Dabry's sturgeon, Acipenser dabryanus, in the Yangtze River

Dabry's sturgeon, Acipenser dabryanus, is a relatively small (130 cm, 16 kg) and now rare sturgeon restricted to the Yangtze River Basin. It behaves as a resident freshwater fish, does not undertake long distance migrations (except for spawning), and lives in a variety of habitats. It historically spawned in the upper Yangtze River, but the spawning sites are unknown. Acipenser dabryanus reaches maturity earlier than do other Chinese sturgeons, which gives the species aquaculture potential, and artificial spawning has been carried out. However, the native population in the Yangtze has sharply declined in the last two decades due to overfishing, pollution and habitat alteration and destruction, especially since the construction of the Gezhouba Dam, which was built in 1981 across the Yangtze River at Yichang, Hubei Province. Since 1981, Dabry's sturgeon rarely occurs below the Gezhouba Dam because downstream movements are blocked. Clearly, conservation of Dabry's sturgeon must be emphasized. Conservation methods may include protecting habitats, controlling capture and stock replenishment.     

Serum levels of HSP70 and other DAMP proteins can aid in patient diagnosis after traumatic injury

Danger-associated molecular patterns (DAMPs) are activated by endogenous signals that originate from stressed, injured, or necrotic cells, signifying “danger” to the host. In this study, we evaluated the expression of the DAMP heat shock protein 70 (HSP70) in trauma patients with and without secondary infections. Levels of glucose (GLU), procalcitonin (PCT), total cholesterol (T-Chol), and white blood cell (WBC) counts were also evaluated at three time stages after trauma. Our analysis showed that the levels of serum HSP70 in patients with minor, moderate, and severe injuries were significantly higher than in healthy patients at each time point post-injury (P?<?0.01), and levels of serum HSP70 in the severe injury group were significantly higher than in the minor injury group at 1–6 h after trauma (P?=?0.047). HSP70 was correlated with GLU and was negatively correlated with T-Chol in the period 1–6 h after injury (P?=?0.008/0.032). WBC and GLU were elevated after trauma, with mutual positive correlation (P?<?0.001). PCT levels increased later than WBC counts and GLU levels; these levels were correlated at the two later time periods, 24–48 h and 60–90 h (P?=?0.008/0.041). PCT continued to rise in patients with secondary infection, but PCT dropped at the third time period in patients without secondary infection. In summary, our results suggest that danger and stress theory can be used to predict severity of trauma.     

JMJD5 (Jumonji Domain-containing 5) Associates with Spindle Microtubules and Is Required for Proper Mitosis

Precise mitotic spindle assembly is a guarantee of proper chromosome segregation during mitosis. Chromosome instability caused by disturbed mitosis is one of the major features of various types of cancer. JMJD5 has been reported to be involved in epigenetic regulation of gene expression in the nucleus, but little is known about its function in mitotic process. Here we report the unexpected localization and function of JMJD5 in mitotic progression. JMJD5 partially accumulates on mitotic spindles during mitosis, and depletion of JMJD5 results in significant mitotic arrest, spindle assembly defects, and sustained activation of the spindle assembly checkpoint (SAC). Inactivating SAC can efficiently reverse the mitotic arrest caused by JMJD5 depletion. Moreover, JMJD5 is found to interact with tubulin proteins and associate with microtubules during mitosis. JMJD5-depleted cells show a significant reduction of α-tubulin acetylation level on mitotic spindles and fail to generate enough interkinetochore tension to satisfy the SAC. Further, JMJD5 depletion also increases the susceptibility of HeLa cells to the antimicrotubule agent. Taken together, these results suggest that JMJD5 plays an important role in regulating mitotic progression, probably by modulating the stability of spindle microtubules.     

Combination of granulocyte colony-stimulating factor and CXCR4 antagonist AMD3100 for effective harvest of endothelial progenitor cells from peripheral blood and in vitro formation of primitive endothelial networks

Endothelial progenitor cells (EPC) derived from the circulation may be used to enhance neovascularization. Since the combination of granulocyte colony-stimulating factor (GCSF) and CXCR4 antagonist AMD3100 efficiently mobilizes hematopoietic stem cells into peripheral circulation, it may increase the pool of endogenously circulating EPC. We tested this hypothesis by administering GCSF and AMD3100 to adult rabbits and rats, isolating mononuclear cells from peripheral blood by Ficoll density gradient centrifugation, and characterizing the blood-derived EPC based on morphology, immunophenotyping, gene expression and other functional analyses. These EPC showed clonal growth similar to that of human umbilical vein endothelial cells when cultured in complete EGM-2 medium on collagen I-precoated culture plates. The EPC exhibited a typical cobblestone-like morphology and were relatively homogeneous by the third passage. The cells expressed the typical endothelial marker CD31 based on flow cytometry and fluorescence microscopy, formed capillary-like structures when cultured in Matrigel, internalized DiI-acetylated low-density lipoprotein, bound Ulex europaeus agglutinin-1, and expressed CD31 and several other endothelial markers (VEGFR2, VE-cadherin, Tie-2, eNOS, vWF) at significantly higher levels than bone marrow-derived mesenchymal stem cells. These results suggest that the combination of GCSF and AMD3100 can efficiently release stem cells into peripheral circulation and generate EPC that show the desired morphological, immunophenotypic and functional characteristics. This minimally invasive approach may be useful for autologous cell transplantation for postnatal neovasculogenesis and tissue repair.