摘要: Objectives The cellular therapy using adipose-derived mesenchymal stem cells (ASCs) aims to improve tendon healing, considering that repaired tendons often result in a less resistant tissue. Our objective was to evaluate the effects of the ASCs combination with a low-level laser (LLL), an effective photobiostimulation for the healing processes. Materials and methods Rats calcaneal tendons were divided into five groups: normal (NT), transected (T), transected and ASCs (SC) or LLL (L), or with ASCs and LLL (SCL). Results All treated groups presented higher expression of Dcn and greater organization of collagen fibres. In comparison with T, LLL also up-regulated Gdf5 gene expression, ASCs up-regulated the expression of Tnmd, and the association of LLL and ASCs down-regulated the expression of Scx. No differences were observed for the expression of Il1b, Timp2, Tgfb1, Lox, Mmp2, Mmp8 and Mmp9, neither in the quantification of hydroxyproline, TNF-alpha, PCNA and in the protein level of Tnmd. A higher amount of IL-10 was detected in SC, L and SCL compared to T, and higher amount of collagen I and III was observed in SC compared to SCL. Conclusions Transplanted ASCs migrated to the transected region, and all treatments altered the remodelling genes expression. The LLL was the most effective in the collagen reorganization, followed by its combination with ASCs. Further investigations are needed to elucidate the molecular mechanisms involved in the LLL and ASCs combination during initial phases of tendon repair.

摘要: Objectives The odontoblastic differentiation of dental pulp stem cells (DPSCs) contributes to tertiary dentin formation. Our previous study indicated that epiregulin (EREG) enhanced odontogenesis potential of dental pulp. Here, we explored the effects of EREG during DPSC odontoblastic differentiation. Methods The changes in EREG were detected during tertiary dentin formation. DPSCs were treated with recombinant human EREG (rhEREG), EREG receptor inhibitor gefitinib and short hairpin RNAs. The odontoblastic differentiation was assessed with ALP staining, ALP activity assay, alizarin red S staining and real-time RT-PCR of DSPP, OCN, RUNX2 and OSX. Western blot was conducted to examine the levels of p38 mitogen-activated protein kinase (p38 MAPK), c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase 1/2 (Erk1/2). The expression of EREG and odontoblastic differentiation-related markers was investigated in human dental pulp from teeth with deep caries and healthy teeth. Results Epiregulin was upregulated during tertiary dentin formation. rhEREG enhanced the odontoblastic differentiation of DPSCs following upregulated p38 MAPK and Erk1/2 phosphorylation, but not JNK, whereas depletion of EREG suppressed DPSC differentiation. Gefitinib decreased odontoblastic differentiation with decreased phosphorylation of p38 MAPK and Erk1/2. And suppression of p38 MAPK and Erk1/2 pathways attenuated DPSC differentiation. In human dental pulp tissue, EREG upregulation in deep caries correlates with odontoblastic differentiation enhancement. Conclusion Epiregulin is released during tertiary dentin formation. And EREG enhanced DPSC odontoblastic differentiation via MAPK pathways.

摘要: Objectives Topographic cues can modulate morphology and differentiation of mesenchymal stem cells. This study aimed to determine how topographic cues of a novel bilayered poly (lactic-co-glycolic acid) (PLGA) scaffold affect osteogenic/odontogenic differentiation of dental pulp stem cells (DPSCs). Methods The surface morphology of the scaffolds was visualized by scanning electron microscope, and the surface roughness was measured by profilometry. DPSCs were cultured on each side of the scaffolds. Cell morphology, expression of Yes-associated protein (YAP) and osteogenic/odontogenic differentiation were analysed by immunohistochemistry, real-time polymerase chain reaction, and Alizarin Red S staining. In addition, cytochalasin D (CytoD), an F-actin disruptor, was used to examine the effects of F-actin on intracellular YAP localisation. Verteporfin, a YAP transcriptional inhibitor, was used to explore the effects of YAP signalling on osteogenic/odontogenic differentiation of DPSCs. Results The closed side of our scaffold showed smaller pores and less roughness than the open side. On the closed side, DPSCs exhibited enhanced F-actin stress fibre alignment, larger spreading area, more elongated appearance, predominant nuclear YAP localization and spontaneous osteogenic differentiation. Inhibition of F-actin alignments was correlated with nuclear YAP exclusion of DPSCs. Verteporfin restricted YAP localisation to the cytoplasm, down-regulated expression of early osteogenic/odontogenic markers and inhibited mineralization of DPSCs cultures. Conclusions The surface topographic cues changed F-actin alignment and morphology of DPSCs, which in turn regulated YAP signalling to control osteogenic/odontogenic differentiation.

摘要: L-type voltage-gated calcium ion channels (L-VGCCs) have been demonstrated to be the mediator of several significant intracellular activities in excitable cells, such as neurons, chromaffin cells and myocytes. Recently, an increasing number of studies have investigated the function of L-VGCCs in non-excitable cells, particularly stem cells. However, there appear to be no systematic reviews of the relationship between L-VGCCs and stem cells, and filling this gap is prescient considering the contribution of L-VGCCs to the proliferation and differentiation of several types of stem cells. This review will discuss the possible involvement of L-VGCCs in stem cells, mainly focusing on osteogenesis mediated by mesenchymal stem cells (MSCs) from different tissues and neurogenesis mediated by neural stem/progenitor cells (NSCs). Additionally, advanced applications that use these channels as the target for tissue engineering, which may offer the hope of tissue regeneration in the future, will also be explored.

摘要: Objectives The aim of this study was to elucidate the antimitotic mechanism of zerumbone and to investigate its effect on the HeLa cells in combination with other mitotic blockers. Materials and methods HeLa cells and fluorescence microscopy were used to analyse the effect of zerumbone on cancer cell lines. Cellular internalization of zerumbone was investigated using FITC-labelled zerumbone. The interaction of zerumbone with tubulin was characterized using fluorescence spectroscopy. The Chou and Talalay equation was used to calculate the combination index. Results Zerumbone selectively inhibited the proliferation of HeLa cells with an IC50 of 14.2 +/- 0.5 mu mol/L through enhanced cellular uptake compared to the normal cell line L929. It induced a strong mitotic block with cells exhibiting bipolar spindles at the IC50 and monopolar spindles at 30 mu mol/L. Docking analysis indicated that tubulin is the principal target of zerumbone. In vitro studies indicated that it bound to goat brain tubulin with a Kd of 4 mu mol/L and disrupted the assembly of tubulin into microtubules. Zerumbone and colchicine had partially overlapping binding site on tubulin. Zerumbone synergistically enhanced the anti-proliferative activity of vinblastine and paclitaxel through augmented mitotic block. Conclusion Our data suggest that disruption of microtubule assembly dynamics is one of the mechanisms of the anti-cancer activity of zerumbone and it can be used in combination therapy targeting cell division.