Preliminary Study on Human Adipose Stem Cells Promoting Skin Wound Healing Through Notch1 Signaling Pathway

Background: Mesenchymal stem cells (MSCs) have been documented as possible candidates for wound healing treatment because their use could reinforce the regenerative capacity of many tissues. Human adipose stem cells (hADSCs) have the advantages of easy access, large quantity and easy operation. They can be fully applied in the treatment of skin wounds. In this study, we aim to explore the roles and potential mechanisms of hADSCs in cutaneous wound healing.Methods: hADSCs were obtained from human subcutaneous fat. Adipocytes and osteocytes differentiated from hADSCs were determined by staining with Oil Red O and alkaline phosphatase (ALP), respectively. We assessed the effects of hADSCs and hADSC conditional medium (CM) on wound healing in an injury model of mice. Than, we investigated the biological effects of hADSCs on human keratinocytes HaCAT cells in vitro.Results: The results showed that hADSCs could be successfully differentiated into osteogenic and lipogenic cells. hADSCs and hADSCs-CM significantly promote skin wound healing in vivo. hADSCs significantly promoted HaCAT cells proliferation and migration through activating Notch1 signaling pathway, and activated the AKT signaling pathway by Rps6kb1 kinase in HaCAT cells. In addition, we found that hADSCs-mediated activation of Rps6kb1/AKT signaling was dependent on the Notch1 signaling pathway.Conclusion: We demonstrated that hADSCs can promote skin cell-HaCAT cells proliferation and migration via Notch1 pathway, suggesting that hADSCs may provide an alternative therapeutic approach for the treatment of skin injury.

Cyclophosphamide inhibits Pax5 methylation to regulate the growth of retinoblastoma via the Notch1 pathway

Retinoblastoma (Rb) is the most common intraocular malignant tumor in infants. Here, we investigated the function and mechanism of cyclophosphamide (CTX) in the development of Rb. Real-time quantitative polymerase chain reaction (RT-qPCR) results showed that paired box protein 5 (Pax5) expression was down-regulated in Rb tissues and cell lines. Methylation-specific PCR (MSP) results showed that the methylation level of Pax5 was up-regulated in Rb. After treatment with CTX, the Pax5 expression in Rb cell lines was increased significantly. The methylation of Pax5 and the expression of DNA methyltransferases (DNMTs) were down-regulated in the CTX group. Cyclophosphamide inhibited cell proliferation, migration, and invasion, promoted cell apoptosis via the Notch1 pathway. DNA methyltransferase inhibitor SGI-1027 had synergistic effects with CTX. Paired box protein 5 siRNA was transfected into Y79 cells treated with CTX. The expression of DNMTs, Pax5, the Notch1 pathway and apoptosis marker protein was detected by Western blotting, and changes in cell behavior were detected, respectively. Results showed that knockdown of Pax5 reversed the effects of CTX. Moreover, the Notch1 activator Valproic acid (VPA) abolished the inhibitory effects of CTX on Rb development. Moreover, CTX inhibited tumor growth in nude mice. These findings demonstrated that CTX up-regulated Pax5 expression by down-regulating DNMTs expression, and then inhibited the Notch1 signaling pathway activation and Rb growth.

Based on Dll4/Notch1 Signaling Pathway to Elucidate the Therapeutic Effect and Mechanism of L-borneolum on Cerebral Ischemic Stroke Rats

Background: The current research progress suggests that a single therapy may not be ideal means for complex cerebral ischemic stoke (CIS). l-Borneolum is the crystallization of fresh leaves of Blumea balsamifera (L.) DC, we have found that l-borneolum plays a best anti-cerebral ischemic effect than d-borneolum or synthetic borneolum. However, the mechanism is needed to be explored in depth. Therefore, based on comprehensive approach that combines molecular docking technology and molecular biology, this stiudy aimed to investigate the potential mechanism of l-borneolum on CIS rats and provide scientific evidence for the treatment of l-borneolum in CIS.Methods: Cerebral ischemic stroke (CIS) rats with permanent middle cerebral artery occlusion (pMCAO) were applied to this study. The modified neurological severity scores (mNSS) and Longa neurological function scoring methods were used to assess the neurobehavioral scores. 2,3,5-Triphenyltetrazolium chloride (TTC) staining and hematoxylin-eosin (HE) staining were used to evaluate pathological changes of cerebral tissue. Ultrastructure of cortical capillary and blood-brain barrier (BBB) in rats were observed by transmission electron microscopy. In addition, the protein expression of Notch1, Dll4, Hey1, Hes1, Hes5, VEGFA and p65 in the cortex of rats were determined by Western blotting (WB). The protein contents of Caspase 3 in the cortex of rats were determined by immunohistochemical method (IHC). Results: l-Borneolum could prolong the resuscitation time, reduce the abnormal increased rectal temperature, improve neurological function in a dose-dependently. Additionally, l-borneolum could significantly alleviate brainstem edema and inflammation, as well as improve the ultrastructure of capillary and BBB in cortex. Moreover, 0.2 g/kg l-borneolum could substantially decrease the protein expressions of Dll4, Notch1, Hes1, Hes5, and VEGFA in the cortex while it decreased the level of Caspase-3 in the cortex of rats. Conclusions: l-Borneolum could repair neurological function by regulating Dll4/Notch1 signaling pathway, l-borneolum might be a good complementary agent for CIS.

Oncogene APOL1 promotes proliferation and inhibits apoptosis via activating NOTCH1 signaling pathway in pancreatic cancer

APOL1 encodes a secreted high-density lipoprotein, which has been considered as an aberrantly expressed gene in multiple cancers. Nevertheless, the role of APOL1 in the regulatory mechanisms of pancreatic cancer remains unknown and should be explored. We identified APOL1 was abnormally elevated in human pancreatic cancer tissues compared with that in adjacent tissues and was associated with poor prognosis. The effects of APOL1 in PC cell proliferation, cell cycle, and apoptosis was verified via functional in vitro and in vivo experiments. The results showed that knockdown of APOL1 significantly inhibited the proliferation and promoted apoptosis of pancreatic cancer. In addition, we identified APOL1 could be a regulator of NOTCH1 signaling pathway using bioinformatics tools, qRT-PCR, dual-luciferase reporter assay, and western blotting. In summary, APOL1 could function as an oncogene to promote proliferation and inhibit apoptosis through activating NOTCH1 signaling pathway expression in pancreatic cancer; therefore, it may act as a novel therapeutic target for pancreatic cancer.