Study on the Protective Effects of Compound Blood-activating Soup on Bone Marrow Hematopoietic Cells in Acute Radiation Injured Mice

After irradiation with 8 Gy 60Coγ-ray,mice were immediaterly given intraperitoneal injection of 200 mg 100 % compound blood-activating soup twice a day. On the 3rd and 7th day, the P53 gene expression of bone marrow hematopoietic cells in Chinese drug group was found to be higher than that in normal group, and it was also significantly higher than that in control group. The expression level of GADD153 gene which was not expressed in normal group was much lower in Chinese drug group than that in control group. On the 7th day after irradiation, the P53 and GADD153 gene expression levels of splenic mononuclear cells were consistent with those of bone marrow hematopoietic cells both in Chinese drug group and control group. On the 3rd and 7th day, the bone marrow hematopoietic tissue volume in Chinese drug group was higher than that in control group, with no difference found between the two groups. While on the 14th day, the difference became significant (P＜0. 01). The results showed that commonly used blood-activating and stasis-eliminating drugs may strengthen .the viability of hematopoietic cells and promote the rehabilitation of hematopoiesis by inducing wt-P53 expression to block the bone marrow hematopoietic cells in G1 phase, during which DNA could be repaired.

Long non-coding RNA NONMMUG014387 promotes Schwann cell proliferation after peripheral nerve injury

Schwann cells play a critical role in peripheral nerve regeneration through dedifferentiation and proliferation. In a previous study, we performed microarray analysis of the sciatic nerve after injury. Accordingly, we predicted that long non-coding RNA NONMMUG014387 may promote Schwann cell proliferation after peripheral nerve injury, as bioinformatic analysis revealed that the target gene of NONMMUG014387 was collagen triple helix repeat containing 1（Cthrc1）. Cthrc1 may promote cell proliferation in a variety of cells by activating Wnt/PCP signaling. Nonetheless, bioinformatic analysis still needs to be verified by biological experiment. In this study, the candidate long non-coding RNA, NONMMUG014387, was overexpressed in mouse Schwann cells by recombinant adenovirus transfection. Plasmid p HBAd-MCMV-GFP-NONMMUG014387 and p HBAd-MCMV-GFP were transfected into Schwann cells. Schwann cells were divided into three groups： control（Schwann cells without intervention）, Ad-GFP（Schwann cells with GFP overexpression）, and Ad-NONMMUGO148387（Schwann cells with GFP and NONMMUGO148387 overexpression）. Cell Counting Kit-8 assay was used to evaluate proliferative capability of mouse Schwann cells after NONMMUG014387 overexpression. Polymerase chain reaction and western blot assay were performed to investigate target genes and downstream pathways of NONMMUG014387. Cell proliferation was significantly increased in Schwann cells overexpressing lnc RNA NONMMUG014387 compared with the other two groups. Further, compared with the control group, m RNA and protein levels of Cthrc1, Wnt5 a, ROR2, Rho A, Rac1, JNK, and ROCK were visibly up-regulated in the Ad-NONMMUGO148387 group. Our findings confirm that long non-coding RNA NONMMUG014387 can promote proliferation of Schwann cells surrounding the injury site through targeting Cthrc1 and activating the Wnt/PCP pathway.

Increased levels of miR-3099 induced by peripheral nerve injury promote Schwann cell proliferation and migration

MicroRNAs(miRNAs) can regulate the modulation of the phenotype of Schwann cells. Numerous novel miRNAs have been discovered and identified in rat sciatic nerve segments, including miR-3099. In the current study, miR-3099 expression levels following peripheral nerve injury were measured in the proximal stumps of rat sciatic nerves after surgical crush. Real-time reverse transcription-polymerase chain reaction was used to determine miR-3099 expression in the crushed nerve segment at 0, 1, 4, 7, and 14 days post sciatic nerve injury, which was consistent with Solexa sequencing outcomes. Expression of miR-3099 was up-regulated following peripheral nerve injury. EdU and transwell chamber assays were used to observe the effect of miR-3099 on Schwann cell proliferation and migration. The results showed that increased miR-3099 expression promoted the proliferation and migration of Schwann cells. However, reduced miR-3099 expression suppressed the proliferation and migration of Schwann cells. The potential target genes of miR-3099 were also investigated by bioinformatic tools and high-throughput outcomes. miR-3099 targets genes Aqp4, St8 sia2, Tnfsf15, and Zbtb16 and affects the proliferation and migration of Schwann cells. This study examined the levels of miR-3099 at different time points following peripheral nerve injury. Our results confirmed that increased miR-3099 level induced by peripheral nerve injury can promote the proliferation and migration of Schwann cells.

Ependymal cell proliferation and apoptosis following acute spinal cord injury in the adult rat

BACKGROUND： Studies have reported that spinal cord injury can induce the reactive proliferation of ependymal cells and secondarily cause the apoptosis of nerve cells. However, there is no generally accepted theory on the apoptotic characteristics of ependymal cells in the injured spinal cord. OBJECTIVE： To observe the reactive proliferation and apoptosis of ependymal cells in adult rats following acute spinal cord injury. DESIGN, TIME AND SETTING： A randomized control study based on neuropathology was performed in the Third Military Medical University of Chinese PLA between 2005 and 2007. MATERIALS： Forty healthy, adult, Wistar rats were included in the present study. METHODS： Moderate spinal cord injury was established in twenty rats using Feeney＇s method, while the remaining 20 rats served as controls and were only treated with laminectomy. All rats were injected intraperitoneally with 1.25 mL of BrdU solution （10 mg BrdU/mL saline） 3 times at 4 hours intervals during the 12 hours prior to sacrifice. MAIN OUTCOME MEASURES： Ependymal cell proliferation and apoptosis in the rat spinal cord were determined by BrdU and nestin immunofluorescence double-labeling, as well as the TUNEL method, at 1, 3, 7, and 14 days after operation. RESULTS： In the moderate spinal cord injury rats, nestin expression was observed in the cytoplasm of ependymal cells. One day immediately following surgery, ependymal cells were BrdU-labeled. The number of BrdU-positive cells increased at 3 days, reached a peak at 7 days, and gradually reduced thereafter. The ependyma developed from a constitutive monolayer cells to a multi-layer cell complex. Some BrdU/Nestin double-positive ependymal cells migrated out from the ependyma. TUNEL-positive cells were also detected in the ependyma in the central region, as well as ischemic regions of the injured spinal cord. In addition, TUNEL-positive cells were visible in the ependyma. No TUNEL-positive ependymal cells were observed in the normal spinal cord. CONCLUSION： Proliferating ependymal cells induced apoptosis in the central and surrounding region following spinal cord injury.

F1t3 RECEPTOR EXPRESSION ON THE SURFACE OF MALIGNANT HEMATOPOIETIC CELLS AND RESPONSES TO F1t3 LIGAND STIMULATION

Objective: To investigate the F1t3 receptor expression on the surface of malignant hematopoietic cells, the effect of TNFα and dexamethasone (DXM) on its expression and the responses of those cells to recombinant human F1t3 ligand (rhFL). Methods: Eighteen malignant hematopoietic cell lines were determined for the F1t3 receptor expression by flow cytometric analysis. The effect of rhFL on the proliferation of malignant hematopoietic cellsin vitro was measured using MTT assay. Results: The expressions of F1t3 receptor on the surface of Raji, Daudi, HL-60, 8266 and XG-6 cells were detected by flow cytometric analysis. Following incubation with 20 ng/ml TNFα for 24h, the number of F1t3 receptor positive cells decreased in Raji and 8266, increased in HL-60 and XG-6, and no difference in Daudi cells. After incubation with 10?6 mol/L DXM for 24h, the number of F1t3 receptor positive cells decreased in all the 5 F1t3 receptor positive cell lines. rhFL stimulated the proliferation of HL-60 and Raji cells. Conclusion: For most of the malignant hematopoietic cells, there was neither the expression of F1t3 receptor nor the response to rhFL. DXM may be useful to reduce the effect of FL on the proliferation of some F1t3 receptor positive malignant hematopoietic cells in vitro andin vivo.

Electroacupuncture and moxibustion promote regeneration of injured sciatic nerve through Schwann cell proliferation and nerve growth factor secretion

Using electroacupuncture and moxibustion to treat peripheral nerve injury is highly efficient with low side effects. However, the electroacupuncture-and moxibustion-based mechanisms underlying nerve repair are still unclear. Here, in vivo and in vitro experiments uncovered one mechanism through which electroacupuncture and moxibustion affect regeneration after peripheral nerve injury. We first established rat models of sciatic nerve injury using neurotomy. Rats were treated with electroacupuncture or moxibustion at acupoints Huantiao （GB30） and Zusanli （ST36）. Each treatment lasted 15 minutes, and treatments were given six times a week for 4 consecutive weeks. Behavioral testing was used to determine the sciatic functional index. We used electrophysiological detection to measure sciatic nerve conduction velocity and performed hematoxylin-eosin staining to determine any changes in the gastrocnemius muscle. We used immunohistochemistry to observe changes in the expression of S100—a specific marker for Schwann cells—and an enzyme-linked immunosorbent assay to detect serum level of nerve growth factor. Results showed that compared with the model-only group, sciatic functional index, recovery rate of conduction velocity, diameter recovery of the gastrocnemius muscle fibers, number of S100-immunoreactive cells,and level of nerve growth factor were greater in the electroacupuncture and moxibustion groups. The efficacy did not differ between treatment groups. The serum from treated rats was collected and used to stimulate Schwann cells cultured in vitro. Results showed that the viability of Schwann cells was much higher in the treatment groups than in the model group at 3 and 5 days after treatment. These findings indicate that electroacupuncture and moxibustion promoted nerve regeneration and functional recovery; its mechanism might be associated with the enhancement of Schwann cell proliferation and upregulation of nerve growth factor.

Hyperbaric oxygen treatment promotes neural stem cell proliferation in the subventricular zone of neonatal rats with hypoxic-ischemic brain damage

Hyperbaric oxygen therapy for the treatment of neonatal hypoxic-ischemic brain damage has been used clinically for many years, but its effectiveness remains controversial. In addition, the mechanism of this potential neuroprotective effect remains unclear. This study aimed to investigate the influence of hyperbaric oxygen on the proliferation of neural stem cells in the subventricular zone of neonatal Sprague-Dawley rats （7 days old） subjected to hypoxic-ischemic brain damage. Six hours after modeling, rats were treated with hyperbaric oxygen once daily for 7 days. Immunohistochemistry revealed that the number of 5-bromo-2＇-deoxyuridine positive and nestin positive cells in the subventricular zone of neonatal rats increased at day 3 after hypoxic-ischemic brain damage and peaked at day 5. After hyperbaric oxygen treatment, the number of 5-bromo-2＇- deoxyuddine positive and nestin positive cells began to increase at day 1, and was significantly higher than that in normal rats and model rats until day 21. Hematoxylin-eosin staining showed that hyperbaric oxygen treatment could attenuate pathological changes to brain tissue in neonatal rats, and reduce the number of degenerating and necrotic nerve cells. Our experimental findings indicate that hyperbaric oxygen treatment enhances the proliferation of neural stem cells in the subventricular zone of neonatal rats with hypoxic-ischemic brain damage, and has therapeutic potential for promoting neurological recovery following brain injury.

Novel miRNA, miR-sc14, promotes Schwann cell proliferation and migration

MicroRNAs refer to a class of endogenous,short non-coding RNAs that mediate numerous biological functions.MicroRNAs regulate various physiological and pathological activities of peripheral nerves,including peripheral nerve repair and regeneration.Previously,using a rat sciatic nerve injury model,we identified many functionally annotated novel microRNAs,including miR-sc14.Here,we used real-time reverse transcription-polymerase chain reaction to examine miR-sc14 expression in rat sciatic nerve stumps.Our results show that miRsc14 is noticeably altered following sciatic nerve injury,being up-regulated at 1 day and diminished at 7 days.EdU and transwell chamber assay results showed that miR-sc14 mimic promoted proliferation and migration of Schwann cells,while miR-sc14 inhiThe study was approved by the Jiangsu Provincial Laboratory Animal Management Committee,China on March 4,2015(approval No.20150304-004).bitor suppressed their proliferation and migration.Additionally,bioinformatic analysis examined potential target genes of miR-sc14,and found that fibroblast growth factor receptor 2 might be a potential target gene.Specifically,our results show changes of miR-sc14 expression in the sciatic nerve of rats at different time points after nerve injury.Appropriately,up-regulation of miR-sc14 promoted proliferation and migration of Schwann cells.Consequently,miR-sc14 may be an intervention target to promote repair of peripheral nerve injury.The study was approved by the Jiangsu Provincial Laboratory Animal Management Committee,China on March 4,2015(approval No.20150304-004).

Acetyl-11-keto-β-boswellic acid extracted from Boswellia serrata promotes Schwann cell proliferation and sciatic nerve function recovery

Frankincense can promote blood circulation. Acetyl-11-keto-β-boswellic acid （AKBA） is a small molecule with anti-inflammatory properties that is derived from Boswellia serrata. Here, we hypothesized that it may promote regeneration of injured sciatic nerve. To address this hypothesis, we established a rat model of sciatic nerve injury using a nerve clamping method. Rats were administered AKBA once every 2 days at doses of 1.5, 3, and 6 mg/kg by intraperitoneal injection for 30 days from the 1st day after injury. Sciatic nerve function was evaluated using the sciatic functional index. Degree of muscle atrophy was measured using the triceps surae muscle Cuadros index.Neuropathological changes were observed by hematoxylin-eosin staining. Western blot analysis was used to detect expression of phospho-extracellular signal-regulated kinase 1 and 2 （p-ERK1/2） in injured nerve. S100 immunoreactivity in injured nerve was detected by immunohistochemistry. In vivo experiments showed that 3 and 6 mg/kg AKBA significantly increased sciatic nerve index, Cuadros index of triceps muscle, p-ERK1/2 expression, and S100 immunoreactivity in injured sciatic nerve of sciatic nerve injury model rats. Furthermore,for in vitro experiments, Schwann cells were treated with AKBA at 0–20 μg/mL. Proliferation of Schwann cells was detected by Cell Counting Kit-8 colorimetry assay. The results showed that 2 μg/mL AKBA is the optimal therapeutic concentration. In addition, ERK phosphorylation levels increased following 2 μg/mL AKBA treatment. In the presence of the ERK1/2 inhibitor, PD98059 （2.5 μL/mL）, the AKBA-induced increase in p-ERK1/2 protein expression was partially abrogated. In conclusion, our study shows that AKBA promotes peripheral nerve regeneration with ERK protein phosphorylation playing a key role in this process.

Ischemic accumulation of succinate induces Cdc42 succinylation and inhibits neural stem cell proliferation after cerebral ischemia/reperfusion

Ischemic accumulation of succinate causes cerebral damage by excess production of reactive oxygen species. However, it is unknown whether ischemic accumulation of succinate affects neural stem cell proliferation. In this study, we established a rat model of cerebral ischemia/reperfusion injury by occlusion of the middle cerebral artery. We found that succinate levels increased in serum and brain tissue(cortex and hippocampus) after ischemia/reperfusion injury. Oxygen-glucose deprivation and reoxygenation stimulated primary neural stem cells to produce abundant succinate. Succinate can be converted into diethyl succinate in cells. Exogenous diethyl succinate inhibited the proliferation of mouse-derived C17.2 neural stem cells and increased the infarct volume in the rat model of cerebral ischemia/reperfusion injury. Exogenous diethyl succinate also increased the succinylation of the Rho family GTPase Cdc42 but repressed Cdc42 GTPase activity in C17.2 cells. Increasing Cdc42 succinylation by knockdown of the desuccinylase Sirt5 also inhibited Cdc42 GTPase activity in C17.2 cells. Our findings suggest that ischemic accumulation of succinate decreases Cdc42 GTPase activity by induction of Cdc42 succinylation, which inhibits the proliferation of neural stem cells and aggravates cerebral ischemia/reperfusion injury.

Impact of conditioning regimen on peripheral blood hematopoietic cell transplant

AIM To investigate infused hematopoietic cell doses and their interaction with conditioning regimen intensity +/-total body irradiation(TBI) on outcomes after peripheral blood hematopoietic cell transplant(PBHCT).METHODS Our retrospective cohort included 247 patients receiving a first, T-replete, human leukocyte antigen-matched allogeneic PBHCT and treated between 2001 and2012. Correlations were calculated using the Pearson product-moment correlation coefficient. Overall survival and progression free survival curves were generated using the Kaplan-Meier method and compared using the log-rank test.RESULTS Neutrophil engraftment was significantly faster after reduced intensity TBI based conditioning [reduced intensity conditioning(RIC) + TBI] and > 4 × 10~6 CD34+cells/kg infused. A higher total nucleated cell dose led to a higher incidence of grade II-IV acute graft-versus-host disease in the myeloablative + TBI regimen group(P = 0.03), but no significant difference in grade III-IV graft-versus-host disease. A higher total nucleated cell dose was also associated with increased incidence of moderate/severe chronic graft-versus-host disease, regardless ofconditioning regimen. Overall and progression-free survival were significantly better in patients with a RIC + TBI regimen and total nucleated cell dose > 8 ×10~8/kg(3 years, overall survival: 70% vs 38%, P = 0.02, 3 years, progression free survival: 64% vs 38%, P = 0.02).CONCLUSION TBI and conditioning intensity may alter the relationship between infused cell doses and outcomes after PBHCT. Immune cell subsets may predict improved survival after unmanipulated PBHCT.

Effects of different concentrations of nicotinamide on hematopoietic stem cells cultured in vitro

BACKGROUND In vitro expansion to increase numbers of hematopoietic stem cells(HSCs)in cord blood could improve clinical efficacy of this vital resource.Nicotinamide(NAM)can promote HSC expansion ex vivo,but its effect on hematopoietic stem and progenitor cells(HSPCs,CD34^(+)CD38)and functional subtypes of HSCs-shortterm repopulating HSCs(ST-HSCs,CD34^(+)CD38CD45RACD49f^(+))and long-term repopulating HSCs(LT-HSCs,CD34^(+)CD38CD45RACD49f^(+)CD90^(+))is not yet known.As a sirtuin 1(SIRT1)inhibitor,NAM participates in regulating cell adhesion,polarity,migration,proliferation,and differentiation.However,SIRT1 exhibits dual effects by promoting or inhibiting differentiation in different tissues or cells.We propose that the concentration of NAM may influence proliferation,differentiation,and SIRT1 signaling of HSCs.AIM To evaluate the effects and underlying mechanisms of action of different concentrations of NAM on HSC proliferation and differentiation.METHODS CD34^(+)cells were purified from umbilical cord blood using MacsCD34 beads,and cultured for 10-12 d in a serum-free medium supplemented with cytokines,with different concentrations of NAM added according to experimental requirements.Flow cytometry was used to detect phenotype,cell cycle distribution,and apoptosis of the cultured cells.Real-time polymerase chain reaction was used to detect the transcription levels of target genes encoding stemness-related factors,che mokines,components of hypoxia pathways,and antioxidant enzymes.Dichloro-dihydro-fluorescein diacetate probes were used to evaluate intracellular production of reactive oxygen species(ROS).Determination of the effect of different culture conditions on the balance of cytokine by cytometric bead array.RESULTS Compared with the control group,the proportion and expansion folds of HSPCs(CD34^(+)CD38)incubated with 5 mmol/L or 10 mmol/L NAM were significantly increased(all P<0.05).The ST-HSCs ratio and fold expansion of the 5 mmol/L NAM group were significantly higher than those of the control and 10 mmol/L NAM groups(all P<0.001),whereas the LT-HSCs ratio and fold expansion of the 10 mmol/L NAM group were significantly higher than those of the other two groups(all P<0.05).When the NAM concentration was>10 mmol/L,cell viability significantly decreased.In addition,compared with the 5 mmol/L NAM group,the proportion of apoptotic cells in the 10 mmol/L NAM group increased and the proportion of cells in S and G2 phase decreased.Compared with the 5 mmol/L NAM group,the HSCs incubated with 10 mmol/L NAM exhibited significantly inhibited SIRT1 expression,increased intracellular ROS content,and downregulated expression of genes encoding antioxidant enzymes(superoxide dismutase 1,peroxiredoxin 1).CONCLUSION Low concentrations(5 mmol/L)of NAM can better regulate the balance between proliferation and differentiation,thereby promoting expansion of HSCs.These findings allow adjustment of NAM concentrations according to expansion needs.

Effectiveness of repeated transplantations of hematopoietic stem cells in spinal cord injury

AIM: To evaluate the short and long-term effects of the complex cell therapy of 202 cases of spinal cord injury(SCI).METHODS: The main arm included 202 cases of SCI and the control arm included 20 SCI cases. For the therapy the hematopoietic stem cells(HSCs) and progenitor cells(PCs) were mobilized to peripheral blood by 8 subcutaneous injections of granulocyte colonystimulating factor(G-CSF) for 4 d and are harvested at day 5. The cells were administered to the main arm intrathecally every 3 mo for a long term(3-5 years) according to the internal research protocol international medical institute of tissue engineering. Magnetic resonance imaging of the site of injury and urodyna-mic tests were performed every 6 mo. Motor evoked potentials(MEP), somatosensory evoked potentials(SSEP) were evaluated every 3 mo. The patients were evaluated with american spianl injury association(ASIA) index, functional independence measure index, the Medical Research Council Scale, the International Standards for Neurological Classification of Spinal Cord Injury(ISCSCI-92) and specifically developed scales. The function of bladder was evaluated by a specifically developed clinical scale. The long-term clinical outcomes were assessed for the SCI patients who received no less than 20 intrathecal transplantations of HSCs and hematopoietic precursors(HPs).RESULTS: The restoration of neurologic deficit after HSCs and HPs transplantations was proved stable and evident in 57.4% of the cases. In 42.6% cases no neurologic improvement has been observed. In 50% of the cases the motor restoration began after the first transplantation, which is confirmed in average by 9.9 points improvement in neurologic impairment as compared to the baseline(P < 0.05). Repair of the urinary system was observed in 47.7% of the cases. The sensitivity improved from baseline 124.3 points to 138.4 after the first and to 153.5 points after the second transplantations of HSCs and HPs(P < 0.05, between the stages of research). The evaluation with ASIA index demonstrated regress of neurologic symptoms in 23 cases. Motor progress was also assessed with the ISCISCI-92 motor and sensory scores, and the data coincided with those received with the specifically developed scale. The number of the patients with the signs of locomotive repair was 56.9%. No life threatening complications or adverse effects have been observed.CONCLUSION: The method is safe, effective and considerably improves the life quality of SCI patients. The therapy is approved for clinical use as the treatment of choice.

Satellite cell proliferation and myofiber cross-section area increase after electrical stimulation following sciatic nerve crush injury in rats

Background:Electrical stimulation has been recommended as an effective therapy to prevent muscle atrophy after nerve injury.However,the effect of electrical stimulation on the proliferation of satellite cells in denervated muscles has not yet been fully elucidated.This study was aimed to evaluate the changes in satellite cell proliferation after electrical stimulation in nerve injury and to determine whether these changes are related to the restoration of myofiber cross-section area(CSA).Methods:Sciatic nerve crush injury was performed in 48 male Sprague-Dawley rats.In half(24/48)of the rats,the gastrocnemius was electrically stimulated transcutaneously on a daily basis after injury,while the other half were not stimulated.Another group of 24 male Sprague-Dawley rats were used as sham operation controls without injury or stimulation.The rats were euthanized 2,4,and 6 weeks later.After 5-bromo-2’-deoxyuridine(BrdU)labeling,the gastrocnemia were harvested for the detection of paired box protein 7(Pax7),BrdU,myofiber CSA,and myonuclei number per fiber.All data were analyzed using two-way analysis of variance and Bonferroni post-hoc test.Results:The percentages of Pax7-positive nuclei(10.81±0.56%)and BrdU-positive nuclei(34.29±3.87%)in stimulated muscles were significantly higher compared to those in non-stimulated muscles(2.58±0.33%and 1.30±0.09%,respectively,Bonferroni t=15.91 and 18.14,P<0.05).The numbers of myonuclei per fiber(2.19±0.24)and myofiber CSA(1906.86±116.51 mm2)were also increased in the stimulated muscles(Bonferroni t=3.57 and 2.73,P<0.05),and both were positively correlated with the Pax7-positive satellite cell content(R2=0.52 and 0.60,P<0.01).There was no significant difference in the ratio of myofiber CSA/myonuclei number per fiber among the three groups.Conclusions:Our results indicate that satellite cell proliferation is promoted by electrical stimulation after nerve injury,which may be correlated with an increase in myonuclei number and myofiber CSA.

Neuron-specific enolase expression in a rat model of radiation-induced brain injury following vascular endothelial growth factor-modified neural stem cell transplantation

BACKGROUND： Previous studies have shown that transplantation of vascular endothelial growth factor （VEGF）-modified neural stem cells （NSC） provides better outcomes, compared with neural stem cells, in the treatment of brain damage. OBJECTIVE： To compare the effects of VEGF-modified NSC transplantation and NSC transplantation on radiation-induced brain injury, and to determine neuron-specific enolase （NSE） expression in the brain. DESIGN, TIME, AND SETTING： The randomized, controlled study was performed at the Linbaixin Experimental Center, Second Affiliated Hospital, Sun Yat-sen University, China from November 2007 to October 2008. MATERIALS： VEGF-modified C17.2 NSCs were supplied by Harvard Medical School, USA. Streptavidin-biotin-peroxidase-complex kit （Boster, China） and 5, 6-carboxyfluorescein diacetate succinimidyl ester （Fluka, USA） were used in this study. METHODS： A total of 84 Sprague Dawley rats were randomly assigned to a blank control group （n = 20）, model group （n = 20）, NSC group （n = 20）, and a VEGF-modified NSC group （n = 24）. Rat models of radiation-induced brain injury were established in the model, NSC, and VEGF-modified NSC groups. At 1 week following model induction, 10 pL （5 ×10^4 cells/μL） VEGF-modified NSCs or NSCs were respectively infused into the striatum and cerebral cortex of rats from the VEGF-modified NSC and NSC groups. A total of 10μL saline was injected into rats from the blank control and model groups. MAIN OUTCOME MEASURES： NSE expression in the brain was detected by immunohistochemistry following VEGF-modified NSC transplantation. RESULTS： NSE expression was significantly decreased in the brains of radiation-induced brain injury rats （P 〈 0.05）. The number of NSE-positive neurons significantly increased in the NSC and VEGF-modified NSC groups, compared with the model group （P 〈 0.05）. NSE expression significantly increased in the VEGF-modified NSC group, compared with the NSC group, at 6 weeks following transplantation （P 〈 0.05）. CONCLUSION： VEGF-modified NSC transplantation increased NSE expression in rats with radiation-induced brain injury, and the outcomes were superior to NSC transplantation.

Exendin-4 attenuates atherosclerosis progression via controlling hematopoietic stem/progenitor cell proliferation

Beyond glycemic control, applications of glucagon-like peptide-1 receptor (GLP-1r) agonists (GLP-1 RAs) inhibit inflammationand plaque development in murine atherosclerotic models. However, whether they modulate hematopoietic stem/progenitor cells(HSPCs)to prohibit skewed myelopoiesis in hypercholesteremia remains unknown. In this study, GLP-1r expression in fluorescenceactivated cell sorting (FACS)-sorted wild-type HSPCs was determined by capillary western blotting. Bone marrow cells (BMCs)of wild-type or GLP-1r−/− mice were transplanted into lethally irradiated low-density lipoprotein receptor deficient (LDLr−/−)recipients followed by high-fat diet (HFD) for chimerism analysis by FACS. In parallel, LDLr−/− mice were placed on HFD for 6weeks and then treated with saline or Exendin-4 (Ex-4) for another 6 weeks. HSPC frequency and cell cycle were analyzed byFACS, and intracellular metabolite levels were assessed by targeted metabolomics. The results demonstrated that HSPCs expressedGLP-1r and transplantation of GLP-1r−/− BMCs resulted in skewed myelopoiesis in hypercholesterolemic LDLr−/− recipients.In vitro, Ex-4 treatment of FACS-purified HSPCs suppressed cell expansion and granulocyte production induced by LDL. In vivo, Ex-4treatment inhibited plaque progression, suppressed HSPC proliferation, and modified glycolytic and lipid metabolism in HSPCs ofhypercholesteremic LDLr−/− mice. In conclusion, Ex-4 could directly inhibit HSPC proliferation induced by hypercholesteremia.

Screening for urinary markers predicting hematopoietic stem cell injury induced by busulfan using genetically diverse mice

Background:Busulfan(BU)is an alkylating agent used as a conditioning agent prior to hematopoietic stem cell(HSC)transplantation as it is known to be cytotoxic to host hematopoietic stem and progenitor cells.The susceptibility of HSCs to BU injury plays an important role in the myeloablative efficacy of BU.Different susceptibilities were demonstrated in genetically diverse(GD)mice in our preliminary research.Methods:Three strains of GD mice with different susceptibilities to BU-i nduced HSC injury were used for screening biological markers of HSC injury susceptibility in urine.The urine proteins were analyzed using liquid chromatography coupled with tandem mass spectrometry to screen for differentially expressed proteins.Screening for possible biomarkers based on differences in protein expression abundance was validated using enzyme-l inked immunoassay(ELISA).Results:Functional analysis showed that the differential proteins were all involved in a series of biological pathways related to cellular senescence,apoptosis,and angiogenesis;whereas the differential proteins of the high-susceptible strain were enriched for the regulation of bone marrow microenvironment pathways,those of low-susceptible strain were enriched for the proapoptotic effect of GTPase pathways.Based on protein abundance differences,several urinary proteins that may be indicative of susceptibility were screened,and ELISA validation results showed that angiotensin-converting enzyme may be a potential biomarker predicting HSC susceptibility for BU conditioning.Conclusions:This study indicates that urinary protein levels can reflect differences in susceptibility to BU-i nduced HSC injury.Using GD mice to construct genetic difference models will provide preclinical data for screening BU-related biological markers.

Mesenchymal stem cell therapy for acute radiation syndrome: Innovative medical approaches in military medicine

After a radiological or nuclear event, acute radiation syndrome(ARS) will present complex medical challenges that could involve the treatment of hundreds to thousands of patients. Current medical doctrine is based on limited clinical data and remains inadequate. Efforts to develop medical innovations that address ARS complications are unlikely to be generated by the industry because of market uncertainties specific to this type of injury. A prospective strategy could be the integration of cellular therapy to meet the medical demands of ARS. The most clinically advanced cellular therapy to date is the administration of mesenchymal stem cells(MSCs). Results of currently published investigations describing MSC safety and efficacy in a variety of injury and disease models demonstrate the unique qualities of this reparative cell population in adapting to the specific requirements of the damaged tissue in which the cells integrate. This report puts forward a rationale for the further evaluation of MSC therapy to address the current unmet medical needs of ARS. We propose that the exploration of this novel therapy for the treatment of the multivariate complications of ARS could be of invaluable benefit to military medicine.

The effects of low-dose splenic irradiation and radiotherapy on immune system of patients with locally advanced non-small cell lung cancer

Objective： The aim of the research was to study the effects of low-dose splenic irradiation and radiotherapy on immune system of patients with locally advanced non-small cell lung cancer （NSCLC）. Methods： Twelve cases of stage III NSCLC in Tumor Radiotherapy Center of our hospital （the Affiliated Hospital of Medical College Qingdao University, China） were collected from July 2011 to July 2012; all patients were under 75 years old with clear pathology, measurable lesions and good personal statement. They were randomly divided into combined treatment group （D1 ＋ D2） and control group （D1）. The control group （D1） only received radiotherapy to the chest; combined treatment group （D1 ＋ D2） received low-dose splenic irradiation plus conventional dose irradiation. Flow cytometry was used to detect the peripheral blood T lymphocyte immune indexes of patients before, during and after the treatment, classification by five blood cell analyzer was used to determine white blood cells, neutrophils, hemoglobin and platelet count. The radiation induced toxicity including esophagitis, pneumonia and gastrointestinal reaction was observed, as well as the dose when it happened. Results： There was no significant difference in the ratio between two groups in cells CD4＋, CD8＋ and CD4＋/CD8＋ after radiotherapy （P 〉 0.05）. There was no change in these indicators in combined treatment group after treatment （P 〉 0.05）, but it decreased in control group （P 〈 0.05）. There was no significant difference in the incidences of radiation esophagitis, pneumonia, gastrointestinal reactions and bone marrow suppression between two groups （P 〉 0.05）, but the patients in combined treatment group seemed to tolerate high dose well （P 〈 0.05）. Conclusion： Low-dose splenic irradiation combined with radiotherapy to the chest can alleviate the injury degree of acute radiation induced the toxicity of locally advanced NSCLC patients, through affect the patient＇s immune function.

Claudin-15 overexpression inhibits proliferation and promotes apoptosis of Schwann cells in vitro

Our previous experiments have discovered that Claudin-15 was up-regulated in Schwann cells of the distal nerve stumps of rat models of sciatic nerve injury.However,how Claudin-15 affects Schwann cell function is still unknown.This study aimed to identify the effects of Claudin-15 on proliferation and apoptosis of Schwann cells cultured in vitro and explore the underlying mechanisms.Primary Schwann cells were obtained from rats.Claudin-15 in Schwann cells was knocked down using siRNA(siRNA-1 group)compared with the negative control siRNA transfection group(negative control group).Claudin-15 in Schwann cells was overexpressed using pGV230-Claudin-15 plasmid(pGV230-Claudin-15 group).The pGV230 transfection group(pGV230 group)acted as the control of the pGV230-Claudin-15 group.Cell proliferation was analyzed with EdU assay.Cell apoptosis was analyzed with flow cytometric analysis.Cell migration was analyzed with Transwell inserts.The mRNA and protein expressions were analyzed with quantitative polymerase chain reaction assay and western blot assay.The results showed that compared with the negative control group,cell proliferation rate was up-regulated;p-AKT/AKT ratio,apoptotic rate,p-c-Jun/c-Jun ratio,mRNA expression of protein kinase C alpha,Bcl-2 and Bax were down-regulated;and mRNA expression of neurotrophins basic fibroblast growth factor and neurotrophin-3 were increased in the siRNA-1 group.No significant difference was found in cell migration between the negative control and siRNA-1 groups.Compared with the pGV230 group,the cell proliferation rate was down-regulated;apoptotic rate,p-c-Jun/c-Jun ratio and c-Fos protein expression increased;mRNA expression of protein kinase C alpha and Bax decreased;and mRNA expressions of neurotrophins basic fibroblast growth factor and neurotrophin-3 were up-regulated in the pGV230-Claudin-15 group.The above results demonstrated that overexpression of Claudin-15 inhibited Schwann cell proliferation and promoted Schwann cell apoptosis in vitro.Silencing of Claudin-15 had the reverse effect and provided neuroprotective effect.This study was approved by the Experimental Animal Ethics Committee of Jilin University of China(approval No.2016-nsfc001)on March 5,2016.