DPYSL2 is a novel regulator for neural stem cell differentiation in rats: revealed by Panax notoginseng saponin administration.

BACKGROUND: The limited neuronal differentiation of the endogenous or grafted neural stem cells (NSCs) after brain injury hampers the clinic usage of NSCs. Panax notoginseng saponins (PNS) were extensively used for their clinical value, such as in controlling blood pressure, blood glucose, and inhibiting neuronal apoptosis and enhancing neuronal protection, but whether or not it exerts an effect in promoting neuronal differentiation of the endogenous NSCs is completely unclear and the potential underlying mechanism requires further exploration. METHODS: Firstly, we determined whether PNS could successfully induce NSCs to differentiate to neurons under the serum condition. Mass spectrometry and quantitative polymerase chain reaction (Q-PCR) were then performed to screen the differentially expressed proteins (genes) between the PNS + serum and serum control group, upon which dihydropyrimidinase-like 2 (DPYSL2), a possible candidate, was then selected for the subsequent research. To further investigate the actual role of DPYSL2 in the NSC differentiation, DPYSL2-expressing lentivirus was employed to obtain DPYSL2 overexpression in NSCs. DPYSL2-knockout rats were constructed to study its effects on hippocampal neural stem cells. Immunofluorescent staining was performed to identify the differentiation direction of NSCs after 7 days from DPYSL2 transfection, as well as those from DPYSL2-knockout rats. RESULTS: Seven differentially expressed protein spots were detected by PD Quest, and DPYSL2 was found as one of the key factors of NSC differentiation in a PNS-treated condition. The results of immunostaining further showed that mainly Tuj1 and GFAP-positive cells increased in the DPYSL2-overexpressed group, while both were depressed in the hippocampal NSCs in the DPYSL2-knockout rat. CONCLUSIONS: The present study revealed that the differentiation direction of NSCs could be enhanced through PNS administration, and the DPYSL2 is a key regulator in promoting NSC differentiation. These results not only emphasized the effect of PNS but also indicated DPYSL2 could be a novel target to enhance the NSC differentiation in future clinical trials.

Role of Bone Marrow Mesenchymal Stromal Cells in Attenuating Inflammatory Reaction in Lipopolysaccaride-induced Acute Kidney Injury of Rats Associated with TLR4-NF-κB Signaling Pathway Inhibition.

Bone marrow mesenchymal stromal cells (BMSCs) have positive therapeutic effects on inflammation associated diseases. However, the underlying mechanism is largely unknown. This study was conducted to investigate whether BMSCs could alleviate the inflammation reaction in lipopolysaccaride (LPS)-induced acute kidney injury (septic-AKI) of rats via inhibition of toll-like receptors (TLR4)-nuclear factor-kappa B (NF-κB) signaling pathway. The septic-AKI rat model was established by injecting the 1ml/mg LPS through the femoral vein. Based on this model, rats were subjected to BMSC transplantation, PDTC (a kind of NF-κB inhibitor) administration alone, and combined treatment of the first two together. Results showed that LPS treatment caused the increases of the concentration of blood urea nitrogen (BUN) and serum creatinine (SCr), accompanied by tissue injury and the up-regulation of TLR4 and NF-κB, that was its key downstream signaling molecule, in both mRNA and protein level. Notably, it has been found that BMSCs transplantation significantly reversed the already upregulated concentration of BUN and SCr, dramatically attenuated the event of the tissue injury, and prominently reduced mortality after AKI. These were paralleled by down-regulation of the level of TLR4 and NF-κB. These effects of BMSCs transplantation were similar to those of PDTC treatment. Importantly, the effects in the combination therapy of BMSCs transplantation and PDTC group were much stronger than those of either BMSCs or PDTC used alone. These findings suggest that BMSCs transplantation contributes to therapeutic effects in LPS-induced AKI rat model, and that the most obvious effects occurred in the combined treatment group, with BMSCs and PDTC together, which was tightly associated with inhibition of the TLR4-NF-κB signaling pathway.