Nell-1 promotes the neural-like differentiation of dental pulp cells.

Previous studies showed that Nel-like molecule-1 (Nell-1) can positively regulate odontoblastic differentiation and dentin formation. Intriguingly, our group found that Nell-1 is co-expressed with neural markers. The purpose of this study was to investigate whether Nell-1 protein plays a regulatory role in the differentiation of dental pulp cells into neural-like cells by in vivo and in vitro studies. The expression patterns of Nell-1 and dental pulp neural markers were observed by double immunofluorescence staining in normal dental pulp tissue sections of Wistar rat. Collagen sponge containing Nell-1 protein was added into the pulp cavity of rat molars in order to observe the expression patterns of neural markers in rat dental pulp repair and regeneration model by immunohistochemical staining. Moreover, human dental pulp stem cells (hDPSCs) were cultured, and different concentrations of Nell-1 protein were added for 12 h, 24 h, and 72h. The expression of neural markers was detected by using quantitative real-time polymerase chain reaction and Western blot. Nell-1 was co-expressed with neural markers including substance P (SP) and Nestin in rat dental pulp tissue. The expression of neural markers including SP, neuron-specific enolase (NSE), and Nestin was increased obviously in rat dental pulp tissues stimulated with Nell-1 protein. In cultured hDPSCs induced by Nell-1 protein, the expression of neural markers including glial fibrillary acidic protein (GFAP), Nestin, and ß-III tubulin was increased. Nell-1 plays a positive role in inducing the differentiation of DPSCs into neural-like cells.

Development and in functional study of a bi-specific sustained release drug-loaded nano-liposomes for hepatocellular carcinoma.

BACKGROUND: Lenvatinib (LEN) is a first-line therapy for patients with hepatocellular carcinoma (HCC), but has a larger adverse effect profile. In this study, we developed a liposome with drug-carrying function and magnetic resonance imaging (MRI) imaging function to investigate the targeted drug-carrying function and MRI tracing ability of liposome for HCC. METHODS: Magnetic nano-liposomes (MNL) with dual targeting function of epithelial cell adhesion molecule (EpCAM) and vimentin and capable of encapsulating LEN drugs were prepared. The characterization performance, drug loading efficiency and cytotoxicity of EpCAM/vimentin-LEN-MNL were tested, and the dual-targeting slow release drug loading function and MRI tracing ability were investigated in cellular and animal models. RESULTS: EpCAM/vimentin-LEN-MNL has a mean particle size of 218.37 ± 5.13 nm and a mean potential of 32.86 ± 4.62 mV, and is spherical in shape and can be uniformly dispersed in solution. The encapsulation rate was 92.66 ± 0.73% and the drug loading rate was 9.35 ± 0.16%. It has low cytotoxicity, can effectively inhibit HCC cell proliferation and promote HCC cell apoptosis, and has specific targeting function and MRI tracing ability for HCC cells. CONCLUSIONS: In this study, an HCC-specific dual-targeted sustained-release drug delivery liposome with dual-targeted recognition and sensitive MRI tracer was successfully prepared, which provides an important scientific basis for maximizing the multiple effects of nano-carriers in tumor diagnosis and treatment.

Novel Molecule Nell-1 Promotes the Angiogenic Differentiation of Dental Pulp Stem Cells.

INTRODUCTION: This work aimed to reveal the crucial role of Nell-1 in the angiogenic differentiation of human dental pulp stem cells (DPSCs) alone or co-cultured with human umbilical vein endothelial cell (HUVECs) in vitro and whether this molecule is involved in the pulp exposure model in vivo. METHODS: Immunofluorescence was conducted to ascertain the location of Nell-1 on DPSCs, HUVECs, and normal rat dental tissues. RT-PCR, Western blot, and ELISA were performed to observe the expression levels of angiogenic markers and determine the angiogenic differentiation of Nell-1 on DPSCs alone or co-cultured with HUVECs, as well as in vitro tube formation assay. Blood vessel number for all groups was observed and compared using immunohistochemistry by establishing a rat pulp exposure model. RESULTS: Nell-1 is highly expressed in the nucleus of DPSCs and HUVECs and is co-expressed with angiogenic markers in normal rat pulp tissues. Hence, Nell-1 can promote the angiogenic marker expression in DPSCs alone and co-cultured with other cells and can enhance angiogenesis in vitro as well as in the pulp exposure model. CONCLUSION: Nell-1 may play a positive role in the angiogenic differentiation of DPSCs.

Effects of Nel-like molecule-1 and bone morphogenetic protein 2 combination on rat pulp repair.

Nel-like molecule-1 (NELL-1) is a novel highly specific growth factor that can induce osteoblast differentiation and bone formation as well as odontoblast differentiation. Recent studies have suggested that NELL-1 can synergistically increase bone formation and regeneration with bone morphogenetic protein 2 (BMP2) and inhibit adverse effects induced by BMP2. This study aimed to evaluate the combined effects of NELL-1 and BMP2 on rat pulp repair. The experiment used healthy non-carious maxillary first molars from 60 Wistar rats. Exposed pulps were capped with NELL-1 plus BMP2, NELL-1 alone, and BMP2 alone, and each was absorbed onto a sterile collagen sponge. In the control samples, the collagen sponge alone and Dycal were used as capping agents. After l, 2 and 4 weeks, the rats were sacrificed. The formation of reparative dentin, as well the situation of pulp repair, was detected by hematoxylin-eosin (HE) staining; moreover, the expression of dentin specific protein-dentin sialophosphoprotein (DSPP) and the pro-inflammatory cytokines interleukin-6 (IL6) and interleukin-8 (IL8) was detected by immunohistochemical staining. Quantitative real-time PCR experiment was used to investigate the mRNA levels of IL6 and IL8. The results showed that pulp capping with NELL-1 plus BMP2 in rats had superior ability in inducing reparative dentin formation with dentin tubules and in reducing the inflammatory cell response compared with the other groups. These findings suggested that combined use of NELL-1 and BMP2 could positively regulate pulp repair.