Hydrogel contained valproic acid accelerates bone-defect repair via activating Notch signaling pathway in ovariectomized rats

The purpose was to observe whether valproic acid (VPA) has a positive effect on bone-defect repair via activating the Notch signaling pathway in an OVX rat model. The MC3T3-E1 cells were cocultured with VPA and induced to osteogenesis, and the osteogenic activity was observed by alkaline phosphatase (ALP) staining, Alizarin Red (RES) staining and Western blotting (WB). Then the hydrogel-containing VPA was implanted into the femoral epiphysis bone-defect model of ovariectomized (OVX) rats for 12 weeks. Micro-CT, biomechanical testing, histology, immunofluorescence, RT-qPCR, and WB analysis were used to observe the therapeutic effect and explore the possible mechanism. ALP and ARS staining and WB results show that the cell mineralization, osteogenic activity, and protein expression of ALP, OPN, RUNX-2, OC, Notch 1, HES1, HEY1, and JAG1 of VPA group is significantly higher than the control group. Micro-CT, biomechanical testing, histology, immunofluorescence, and RT-qPCR evaluation show that group VPA presented the stronger effect on bone strength, bone regeneration, bone mineralization, higher expression of VEGFA, BMP-2, ALP, OPN, RUNX-2, OC, Notch 1, HES1, HEY1, and JAG1 of VPA when compared with OVX group. Our current study demonstrated that local treatment with VPA could stimulate repair of femoral condyle defects, and these effects may be achieved by activating Notch signaling pathway and acceleration of blood vessel and bone formation.

Allicin Improves Hepatic Fibrosis by Regulating Notch 1 Pathway

Aim: To discuss effects and mechanisms of allicin in hepatic fibrosis by vivo study. Materials and methods: Dividing 45 rats into 5 groups. Evaluating pathology and fibrosis by HE and Masson staining, measuring α-SMA, Collage III, Notch 1, p-AKT and p-mTOR protein expression by IHC assay and WB assay; LC 3B protein expression were evaluated by Immunofluorescence. Liver function were measured by Elisa assay. Results: With Allicin supplement, rats’ liver function, pathological and Collagen volume fraction were significantly improved with doses-dependent in liver tissues (P < 0.05, respectively); α-SMA, Collage III, Notch 1, p-AKT and p-mTOR protein expression were significantly suppressed with doses-dependent (P < 0.05, respectively); LC 3B protein expression was significantly increased with doses-dependent (P < 0.05, respectively). Conclusion: Allicin improved hepatic fibrosis by authophagy up regulation via regulation Notrch1/AKT/mTOR pathway by vivo study.

Imaging characteristics of young age breast cancer (YABC) focusing on pathologic correlation and disease recurrence

The purpose of this study is to investigate imaging characteristics of young age breast cancer (YABC) focusing on correlation with pathologic factors and association with disease recurrence. From January 2017 to December 2019, patients under 40 years old who were diagnosed as breast cancer were enrolled in this study. Morphologic analysis of tumor and multiple quantitative parameters were obtained from pre-treatment dynamic contrast enhanced breast magnetic resonance imaging (DCE-MRI). Tumor-stroma ratio (TSR), microvessel density (MVD) and endothelial Notch 1 (EC Notch 1) were investigated for correlation with imaging parameters. In addition, recurrence associated factors were assessed using both clinico-pathologic factors and imaging parameters. A total of 53 patients were enrolled. Several imaging parameters derived from apparent diffusion coefficient (ADC) histogram showed negative correlation with TSR; and there was negative correlation between MVD and Ve in perfusion analysis. There were nine cases of recurrences with median interval of 16 months. Triple negative subtype and low CD34 MVD positivity in Notch 1 hotspots showed significant association with tumor recurrence. Texture parameters reflecting tumor sphericity and homogeneity were also associated with disease recurrence. In conclusion, several quantitative MRI parameters can be used as imaging biomarkers for tumor microenvironment and can predict disease recurrence in YABC.

The fate of notch-1 transcript is linked to cell cycle dynamics by activity of a natural antisense transcript

A core imprint of metazoan life is that perturbations of cell cycle are offset by compensatory changes in successive cellular generations. This trait enhances robustness of multicellular growth and requires transmission of signaling cues within a cell lineage. Notably, the identity and mode of activity of transgenerational signals remain largely unknown. Here we report the discovery of a natural antisense transcript encoded in exon 25 of notch-1 locus (nAS25) by which mother cells control the fate of notch-1 transcript in daughter cells to buffer against perturbations of cell cycle. The antisense transcript is transcribed at G1 phase of cell cycle from a bi-directional E2F1-dependent promoter in the mother cell where the titer of nAS25 is calibrated to the length of G1. Transmission of the antisense transcript from mother to daughter cells stabilizes notch-1 sense transcript in G0 phase of daughter cells by masking it from RNA editing and resultant nonsense-mediated degradation. In consequence, nAS25-mediated amplification of notch-1 signaling reprograms G1 phase in daughter cells to compensate for the altered dynamics of the mother cell. The function of nAS25/notch-1 in integrating G1 phase history of the mother cell into that of daughter cells is compatible with the predicted activity of a molecular oscillator, slower than cyclins, that coordinates cell cycle within cell lineage.

Intracranially injectable multi-siRNA nanomedicine for the inhibition of Glioma Stem Cells

Background Nanoparticle siRNA-conjugates are promising clinical therapeutics as indicated by recent US-FDA approval. In glioma stem cells (GSC), multiple stemness associated genes were found aberrant. We report intracranially injectable, multi-gene targeted siRNA nanoparticle-gel (NPG) for the combinatorial silencing of three aberrant genes, thus inhibiting the tumorogenic potential of GSCs. Methods NPG loaded with siRNAs targeted against FAK, NOTCH-1, SOX-2 were prepared by the self-assembly of siRNAs with protamine–hyaluronic acid combination. Electron microscopy, DLS and agarose gel electrophoresis were used for the physicochemical characterisation. Cell transfection and gene-silencing efficiency were studied using human mesenchymal stem cells and rat C6 glioma derived GSCs. Neurosphere inhibition was tested in vitro using GSCs derived from C6 cell line and glioma patient samples. Patient-Derived-Xenograft model and orthotopic rat glioma model were used to test the effect of NPG on in vivo tumorigenicity. Results The siRNA nanoparticles with an average size ~ 250nm and ~ 95% loading efficiency showed cellular uptake in ~95.5% GSCs. Simultaneous gene-silencing of FAK, NOTCH-1, and SOX-2 led to the inhibition of neurosphere formation by GSCs, whereas normal stem cells remained unaffected and retained neuronal differentiation capability. GBM PDX models manifested significant impairment in the tumorigenic potential of NPG treated GSCs. Intracranial injection of NPG inhibited tumour growth in orthotopic rat brain tumour model. Conclusion Intracranially injectable n-siRNA nanoparticle-gel targeted to multiple stem-cell signalling impair glioma initiation capabilities of GSCs and inhibited tumour growth in vivo.