Bone morphogenetic protein 7 mediates stem cells migration and angiogenesis:therapeutic potential for endogenous pulp regeneration

Pulp loss is accompanied by the functional impairment of defense,sensory,and nutrition supply.The approach based on endogenous stem cells is a potential strategy for pulp regeneration.However,endogenous stem cell sources,exogenous regenerative signals,and neovascularization are major difficulties for pulp regeneration based on endogenous stem cells.Therefore,the purpose of our research is to seek an effective cytokines delivery strategy and bioactive materials to reestablish an ideal regenerative microenvironment for pulp regeneration.In in vitro study,we investigated the effects of Wnt3a,transforming growth factor-beta 1,and bone morphogenetic protein 7(BMP7)on human dental pulp stem cells(h-DPSCs)and human umbilical vein endothelial cells.2D and 3D culture systems based on collagen gel,matrigel,and gelatin methacryloyl were fabricated to evaluate the morphology and viability of h-DPSCs.In in vivo study,an ectopic nude mouse model and an in situ beagle dog model were established to investigate the possibility of pulp regeneration by implanting collagen gel loading BMP7.We concluded that BMP7promoted the migration and odontogenic differentiation of h-DPSCs and vessel formation.Collagen gel maintained the cell adhesion,cell spreading,and cell viability of h-DPSCs in 2D or 3D culture.The transplantation of collagen gel loading BMP7 induced vascularized pulp-like tissue regeneration in vivo.The injectable approach based on collagen gel loading BMP7 might exert promising therapeutic application in endogenous pulp regeneration.

Transfusion of CXCR4-priming endothelial progenitor cells reduces cerebral ischemic damage and promotes angiogenesis and neurogenesis in db/db diabetic mice

Previous studies suggest that reduction and dysfunction of circulating endothelial progenitor cells(EPCs),and dysregulation in stromal cell derived factor-1/CXC-chemokine receptor 4(SDF-1/ CXCR4) axis in diabetes could be therapeutic targets for diabetic ischemic stroke.This study investigated the efficacy of CXCR4-priming EPCs on cerebral repair following ischemic stroke in db/db diabetic mice.Bone marrow derived EPCs from db/+ control mice were transfected with adenovirus(1×10~7 IU) carrying CXCR4(Ad-CXCR4-EPCs)or null(Ad- null-EPCs).The db/db mice were divided into three groups for EPCs injection(2×10~5 cells/100μl): Ad-CXCR4-EPCs,Ad-null-EPCs or saline(vehicle), via tail vein 2 hrs after middle cerebral artery occlusion (MCAO) surgery.Cerebral blood flow(CBF) was measured with laser Doppler flowmeter.Mice were sacrificed at 2 or 7 days thereafter.Level of circulating EPCs was measured by flow cytometry. Ischemic damage,cerebral microvascular density (MVD),angiogenesis and neurogenesis were determined by histological staining with Fluoro-J,CD31, CD31 +BrdU,NeuN +BrdU,GFAP+BrdU,respectively. Results(table) showed:1) Levels of CXCR4 expression were reduced in the brain and EPCs of db/db mice as measured by real-time RT-PCR and western blot analyses(data not shown);2) The level of circulating EPCs was more in the mice treated with Ad-CXCR4-EPCs;3)EPC transfusion improved CBF,increased MVD,angiogenesis and neurogenesis in peri-infarct area,and decreased ischemic damage.The efficacies were better in Ad-CXCR4 -EPCs group.Data suggest that transfusion of Ad-CXCR4-EPCs could be a therapeutic avenue for ischemia stroke in diabetes.

Host immune cellular reactions in corneal neovascularization

Corneal neovascularization（CNV） is a global important cause of visual impairment. The immune mechanisms leading to corneal heme- and lymphangiogenesis have been extensively studied over the past years as more attempts were made to develop better prophylactic and therapeutic measures. This article aims to discuss immune cells of particular relevance to CNV, with a focus on macrophages, Th17 cells, dendritic cells and the underlying immunology of common pathologies involving neovascularization of the cornea. Hopefully, a thorough understanding of these topics would propel the efforts to halt the detrimental effects of CNV.

Magnetic resonance imaging and cell-based neurorestorative therapy after brain injury

Restorative cell-based therapies for experimental brain injury, such as stroke and traumatic brain injury,substantially improve functional outcome. We discuss and review state of the art magnetic resonance imaging methodologies and their applications related to cell-based treatment after brain injury. We focus on the potential of magnetic resonance imaging technique and its associated challenges to obtain useful new information related to cell migration, distribution, and quantitation, as well as vascular and neuronal remodeling in response to cell-based therapy after brain injury. The noninvasive nature of imaging might more readily help with translation of cell-based therapy from the laboratory to the clinic.

Neamine Inhibits Growth of Pancreatic Cancer Cells In Vitro and In Vivo

Neamine, a non-toxic derivative of neomycin, has recently been shown to have antitumor activities in various types of cancers. However, its effect on pancreatic cancer is still unknown. The study aimed to investigate its antitumor activity on pancreatic cancer and the underlying mechanisms. MTT assay was used to observe the effect of neamine on angiogenin（ANG）-induced As PC-1 cell proliferation. Tissue microassay and immunofluorescence staining were used to detect the expression of ANG and its nuclear translocation, respectively. Tumor xenografts were established by subcutaneous inoculation of As PC-1 pancreatic cancer cells into the right flanks of nude mice, and neamine was injected subcutaneously. Immunohistochemistry was done to observe the expression of ANG, CD31 and Ki-67 in tumor xenografts. It was found that neamine blocked the nuclear translocation of ANG effectively and inhibited ANG-induced As PC-1 cell proliferation in a dose-dependent manner. Neamine had anti-tumor effects on As PC-1 xenograft models. Consistently, neamine reduced the expression levels of ANG, Ki-67 and CD31 in tumor xenografts. It was concluded that neamine may be a promising agent for treatment of pancreatic cancer.

Hypoxia Downregulates the Angiogenesis in Human Placenta via Notch1 Signaling Pathway

Placentation, which is critical for maternal-fetal exchange of nutrients and gases, is a complicated process comprising stepwise vasculogenesis and angiogenesis. Hypoxia caused by impaired trophoblast invasion may cause various angiogenic abnormalities in human placenta. The Notch1 signaling pathway plays an important role in the regulation of angiogenesis. The angiogenesis of human umbilical vein endothelial cells（HUVECs） under normal/hypoxic conditions and the m RNA/protein level of Notch1/Dell4/Jagged1 were investigated in this study. The effects of DAPT/JAG-1 on the migration of HUVECs were also assessed by cell wound healing assay, so as to discover the possible role of notch1 signaling pathway in the angiogenesis of human placenta. The results showed that angiogenic ability of HUVECs was seriously reduced under hypoxic conditions. The m RNA and protein levels of Notch1/Dell4/Jagged1 were decreased in the hypoxic group compared to the control one. In addition, the migration capability of HUVECs was significantly obstructed when treated with DAPT and under hopoxic condition, but promoted when treated with JAG-1. The above results demonstrate that hypoxia downregulates the angiogenesis in human placenta via Notch1 signaling pathway.