ABSTRACT
The local microenvironment is essential to stem cell-based therapy for ischemic stroke, and spatiotemporal changes of the microenvironment in the pathological process provide vital clues for understanding the therapeutic mechanisms. However, relevant studies on microenvironmental changes were mainly confined in the acute phase of stroke, and long-term changes remain unclear. This study aimed to investigate the microenvironmental changes in the subacute and chronic phases of ischemic stroke after stem cell transplantation. Herein, induced pluripotent stem cells (iPSCs) and neural stem cells (NSCs) were transplanted into the ischemic brain established by middle cerebral artery occlusion surgery. Positron emission tomography imaging and neurological tests were applied to evaluate the metabolic and neurofunctional alterations of rats transplanted with stem cells. Quantitative proteomics was employed to investigate the protein expression profiles in iPSCs-transplanted brain in the subacute and chronic phases of stroke. Compared with NSCs-transplanted rats, significantly increased glucose metabolism and neurofunctional scores were observed in iPSCs-transplanted rats. Subsequent proteomic data of iPSCs-transplanted rats identified a total of 39 differentially expressed proteins in the subacute and chronic phases, which are involved in various ischemic stroke-related biological processes, including neuronal survival, axonal remodeling, antioxidative stress, and mitochondrial function restoration. Taken together, our study indicated that iPSCs have a positive therapeutic effect in ischemic stroke and emphasized the wide-ranging microenvironmental changes in the subacute and chronic phases.
Subject(s)
Animals , Rats , Cell Differentiation , Disease Models, Animal , Ischemic Stroke , Proteomics , Stem Cell Transplantation/methods , Stroke/therapyABSTRACT
ObjectiveTo study the effects of 6-hydroxydopamine (6-OHDA),and inhibitors for vesicular monoamine transporter (VMAT) on 5-hydroxytryptamine (5-HT),norepinephrine (NE) and dopamine (DA) and the expressions of tryptophan hydroxylase (TpH) mRNA,dopamine-beta-hydroxylase (DβH) mRNA and tyrosine hydroxylase (TH) mRNA in PC12 cells.Methods The cell viability was determined using MTT assay, the density of 5-HT, NE and DA was detected using enzyme-linked immunosorbent assay,and the expressions of TpHmRNA,DβHmRNA and THmRNA were detected using RT-PCR in PC12 cells at different time points (0,12,24,36,48 h )after exposure to different concentrations of 6-OHDA(25,50,100,200 μmol/L),and VMAT inhibitors,reserpine (50,100,400,1600 nmol/L),which combined with 6-OHDA( 100 μmol/L).Results (1)The cell viability declined with the increasing concentration of 6-OHDA which showed time dependence.The cell viability in PC12 cell which treated with reserpine decreased significantly in the responding group.The density of 5-HT in PC12 cell did not decrease with the increasing concentration of 6-OHDA,but the change had the time dependence,and the density of 5-HT was lowest at 36 h.The density of NE decreased with the increasing concentration of 6-OHDA which showed time dependence. The density of DA in PC12 cell decreased with the increasing concentration of 6-OHDA,but the change did not have the time dependence.The density of 5-HT,NE and DA in PC12 cell which treated with reserpine decreased significantly in the responding group. (2) The expressions of TpHmRNA, DβHmRNA and THmRNA in PC12 cell decreased with the increasing concentration of 6-OHDA which showed time dependence.The expressions of TpHmRNA(0.006 ± 0.001,0.003 ± 0.000,0.003 ± 0.000,0.002 ± 0.000) ; DβHmRNA (0.005 ± 0.002,0.003 ± 0.001,0.002 ±0.001,0.001 ± 0.000) and THm RNA (0.005 ± 0.002,0.003 ± 0.001,0.002 ± 0.001,0.001 ± 0.000) in PC12 cell which treated with reserpine decreased significantly in the responding group(F =13.336,9.000,9.393,all P =0.000).Conclusions6-OHDA can decrease the cell viability in PC12 cell,reduce the density of 5-HT,NE and DA and decrease the expressions of TpHmRNA,DβHmRNA and THmRNA,and the effects have dose and time dependence.Reserpine can aggravate this damage.