SDF-1α Levels Research Articles

Lecithin-based deferoxamine nanoparticles accelerated cutaneous wound healing in diabetic rats

Nanoparticles have higher frequency of being exposed to cells or tissue, and are thus more likely to gain access into cytoplasm or nuclei to modulate molecular events due to significantly larger surface area to volume ratio. As a result, they present amplified response or even different physiochemical and biomedical properties from bigger particles. Deferoxamine accelerates wound healing in diabetic rats by increased neovascularization, reduced inflammation and improved maturation of wound. We investigated the wound healing potential of deferoxamine-nanoparticles in diabetic rats. Lecithin based nanoparticles of deferoxamine were prepared and characterized. The diabetic rats were divided into five Groups, of which Group I was treated with pluronic-gel f-127 (25%), Group II with deferoxamine 0.1% and Group III, IV and V were treated with deferoxamine-nanoparticles incorporated in pluronic-gel f-127 25% at 0.03% (0.01% deferoxamine), 0.1% (0.03% deferoxamine) and 0.3% (0.1% deferoxamine) w/v respectively. The wound closure was significantly accelerated in group V as compared to control groups. HIF-1α, VEGF, SDF-1α, TGF-β1, and IL-10 protein levels were significantly higher in group V. The collagen deposition and neovascularization was greater in deferoxamine-nanoparticle treated rats. In contrast, TNF-α level was lowest in group V. In summary, the deferoxamine-nanoparticle formulation we developed, when applied topically on diabetic wounds results in faster wound healing as compared to simple deferoxamine formulation. This formulation may prove to be an effective therapy for treatment of diabetic wounds.

Stromal cell-derived factor-1α promotes recruitment and differentiation of nucleus pulposus-derived stem cells.

BACKGROUNDIntervertebral disc (IVD) degeneration is a condition characterized by a reduction in the water and extracellular matrix content of the nucleus pulposus (NP) and is considered as one of the dominating contributing factors to low back pain. Recent evidence suggests that stromal cell-derived factor 1α (SDF-1α) and its receptor C-X-C chemokine receptor type 4 (CXCR4) direct the migration of stem cells associated with injury repair in different musculoskeletal tissues.AIMTo investigate the effects of SDF-1α on recruitment and chondrogenic differentiation of nucleus pulposus-derived stem cells (NPSCs).METHODSWe performed real-time RT-PCR and enzyme-linked immunosorbent assay to examine the expression of SDF-1α in nucleus pulposus cells after treatment with pro-inflammatory cytokines in vitro. An animal model of IVD degeneration was established using annular fibrosus puncture in rat coccygeal discs. Tissue samples were collected from normal control and degeneration groups. Differences in the expression of SDF-1α between the normal and degenerative IVDs were analyzed by immunohistochemistry. The migration capacity of NPSCs induced by SDF-1α was evaluated using wound healing and transwell migration assays. To determine the effect of SDF-1α on chondrogenic differentiation of NPSCs, we conducted cell micromass culture and examined the expression levels of Sox-9, aggrecan, and collagen II. Moreover, the roles of SDF-1/CXCR4 axis in the migration and chondrogenesis differentiation of NPSCs were analyzed by immunofluorescence, immunoblotting, and real-time RT-PCR.RESULTSSDF-1α was significantly upregulated in the native IVD cells cultured in vitro with pro-inflammatory cytokines, such as interleukin-1β and tumor necrosis factor-α, mimicking the degenerative settings. Immunohistochemical staining showed that the level of SDF-1α was also significantly higher in the degenerative group than in the normal group. SDF-1α enhanced the migration capacity of NPSCs in a dose-dependent manner. In addition, SDF-1α induced chondrogenic differentiation of NPSCs, as evidenced by the increased expression of chondrogenic markers using histological and immunoblotting analyses. Real-time RT-PCR, immunoblotting, and immunofluorescence showed that SDF-1α not only increased CXCR4 expression but also stimulated translocation of CXCR4 from the cytoplasm to membrane, accompanied by cytoskeletal rearrangement. Furthermore, blocking CXCR4 with AMD3100 effectively suppressed the SDF-1α-induced migration and differentiation capacities of NPSCs.CONCLUSIONThese findings demonstrate that SDF-1α has the potential to enhance recruitment and chondrogenic differentiation of NPSCs via SDF-1/CXCR4 chemotaxis signals that contribute to IVD regeneration.

Accelerated infected wound healing by topical application of encapsulated Rosemary essential oil into nanostructured lipid carriers

The pathogenic bacteria delay wound healing due to their interaction in the wound area. This study is aimed to evaluate the efficiency of topical rosemary essential oil (REO) loaded into the nanostructured lipid carriers (NLCs) on in vitro antibacterial activity and in vivo infected wound healing process in the animal model. REO-NLCs morphology, size and in vitro antibacterial activity were done. Two circular full-thickness wound (each 6 mm) were made on the back of each mouse and each wound was infected with a solution containing 107 CFU Staphylococcus aureus and Pseudomonas aeruginosa. Animals were divided into four groups including control, Mupirocin® and two treated groups with a gel containing REO and REO-NLCs. For this purpose, tissue bacterial count, histological assessment, serum level of IL-3, IL-10, VEGF and SDF-1α were evaluated. REO-NLCs showed antibacterial activity against Staphylococcus epidermidis, Staphylococcus aureus, Listeria monocytogenes, Escherichia coli and Pseudomonas aeruginosa. Moreover, REO-NLCs could reduce the rate of tissue bacterial colonization and wound size, while they increased the vascularization, fibroblast infiltration, re-epithelialization, collagen production, IL-3, IL-10, VEGF and SDF-1α serum levels. Our finding revealed the REO-NLCs have antibacterial properties and accelerated infected wound healing, and so that confirming their potential clinical uses for the treatment of infected wounds.

Effect of negative-pressure wound therapy on the circulating number of peripheral endothelial progenitor cells in diabetic patients with mild to moderate degrees of ischaemic foot ulcer.

Objective To investigate the effect of negative-pressure wound therapy (NPWT) on the circulating number of endothelial progenitor cells (EPCs) in diabetic patients with mild to moderate degrees of ischemic foot ulcer. Methods We selected 84 diabetic patients who had a foot ulcer with a duration of at least four weeks and who had an ankle-brachial index of 0.5–0.9. Patients were assigned to one two groups according to 2:1 randomization: NPWT group ( n = 56) and non-NPWT (patients who did not receive NPWT) group ( n = 28). The control group (NC group) was composed of 18 patients who had normal glucose tolerance and lower extremity ulcer without arteriovenous disease. NPWT was performed on the ulcer after debridement for one week for patients in both the NPWT group and the NC group, and the patients in the non-NPWT group received conventional treatment process. The circulating number of EPCs was measured before and after various treatments, and the factors influencing their changes were analysed. Results After NPWT, the circulating number of EPCs significantly increased in both the NPWT group and the NC group ((85.3 ± 18.1) vs. (34.1 ± 12.5)/106 cells; (119.9 ± 14.4) vs. (66.1 ± 10.6)/106 cells, both P < 0.05). In contrast, the circulating number of EPCs had no significant change in the non-NPWT group ((45.2 ± 19.4) vs. (34.7 ± 16.8)/106 cells, P > 0.05). In addition, the circulating levels of vascular endothelial growth factor (VEGF) and the protein expressions of VEGF and stromal cell-derived factor-1α (SDF-1α) in the granulation tissue significantly increased after NPWT in both the NPWT and the NC group, but there was no significant change in the non-NPWT group. Compared with the non-NPWT group, the changes in VEGF and SDF-1α levels in the sera and granulation tissue were all significantly higher in both the NPWT and NC groups ( P < 0.05, P < 0.01, respectively). There was no significant difference in changes in the circulating number of EPCs in the peripheral blood and levels of VEGF and SDF-1α in the sera and granulation tissue between the NPWT and NC groups. Correlation analysis showed that the change in the circulating number of EPCs was correlated with the changes of VEGF and SDF-1α levels in the sera and granulation of the NPWT and NC groups ( P < 0.05). Conclusion NPWT may increase the circulating number of EPCs in diabetic patients with mild to moderate ischaemic foot ulcer as in non-diabetic controls, which may be attributed to the upregulation of systemic and local VEGF and SDF-1α levels.

High levels of stromal cell-derived factor-1α predict short-term progression of renal dysfunction in patients with coronary artery disease.

Stromal cell-derived factor-1α (SDF-1α) is an inflammatory chemokine that plays a critical role in cardiovascular disease. Although persistent inflammation causes renal dysfunction, it remains unclear whether SDF-1α is related to progression of chronic kidney disease. This study examined whether high levels of SDF-1α are associated with future declines in renal function in patients with coronary artery disease (CAD). Plasma levels of SDF-1α in the peripheral blood were measured by enzyme-linked immunosorbent assay in 344 patients with CAD. All patients were followed for 24 months or until the occurrence of renal dysfunction, defined as ≥ 25% decrease in estimated glomerular filtration rate (eGFR) from baseline. During the follow-up period, 36 patients developed renal dysfunction. Multivariate logistic regression analysis showed that high plasma levels of SDF-1α were significantly associated with progression of renal dysfunction (odds ratio 1.65; 95% confidence intervals 1.07-2.35, p = 0.03). In addition, high plasma levels of SDF-1α had a significant incremental effect on the predictive value of known risk factors for renal dysfunction in analyses using net reclassification improvement (NRI) and integrated discrimination improvement (IDI) (NRI 0.58 [0.07-1.02], p < 0.01; and IDI 0.030 [0.001-0.085], p = 0.02). High plasma levels of SDF-1α were associated with the short-term decline of eGFR in patients with CAD. Thus, SDF-1α may be useful for predicting the progression of renal dysfunction in patients with CAD.

Inhibitory effects of Chanling Gao on the proliferation and liver metastasis of transplanted colorectal cancer in nude mice.

This study aimed to explore the efficacy and mechanism of Chanling Gao (CLG), a compound Chinese medicine, on colorectal cancer (CRC). A model of transplanted CRC was established in nude mice. The mice were treated 7 days after CRC transplantation with either Capecitabine or CLG for 3 weeks. On the 28th day after the operation, CRC growth and liver metastasis were assessed by morphology, the changes in the expression of HIF-1α (hypoxia inducible factor-1α), stromal cell–derived factor-1 alpha (SDF-1α), CXCR4 (C-X-C chemokine receptor type 4), PI3K, and Akt in the transplanted tumor and SDF-1α and CXCR4 in the liver were detected by Western blot and immunohistochemistry. The protein contents of vascular endothelial growth factor (VEGF), matrix metalloproteinase (MMP)-2, and collagen IV in the serum and transplanted tumor and SDF-1α and CXCR4 in liver tissues were detected by enzyme-linked immunosorbent assay. In the Capecitabine and high dose CLG groups, the growth and liver metastasis of CRC were significantly inhibited, the protein levels of HIF-1α, SDF-1α, CXCR4, MMP-2, VEGF, PI3K, Akt, P-PI3K and P-Akt in the transplanted tumor were lower, while the content of collagen IV in the transplanted tumor was higher, than in Model group. A high dose of CLG inhibited the growth of transplanted tumor and liver metastasis of CRC in nude mice, probably by inhibiting the HIF-1α/SDF-1α-CXCR4/PI3K-Akt signaling pathway reducing the synthesis and release of VEGF and degradation of collagen IV.

The stromal cell-derived factor-1 α (SDF-1α)/cysteine-X-cysteine chemokine receptor 4 (CXCR4) axis: a possible prognostic indicator of acute ischemic stroke.

ObjectiveThe stromal cell-derived factor-1α/cysteine-X-cysteine chemokine receptor 4 (SDF-1α/CXCR4) axis promotes neuroprotection and angiogenesis in animal studies. Few studies have investigated the potential clinical implications of the SDF-1α/CXCR4 axis in patients with acute ischemic stroke (AIS). We evaluated the prognostic values of the SDF-1α/CXCR4 axis in patients with proximal middle cerebral artery occlusion.MethodsFifty-five patients and 18 age- and sex-matched volunteers were enrolled. Baseline clinical characteristics and risk factors of stroke were recorded. Peripheral whole blood cells were double stained with anti-CD34 and anti-CXCR4 (CD184). CD34+CXCR4+ cells were analyzed by flow cytometry. Plasma SDF-1α levels were measured by enzyme-linked immunosorbent assay.ResultsIn the AIS group, plasma SDF-1α levels and the number of circulating CD34+CXCR4+ cells were significantly higher than those in controls. Day 1 SDF-1α levels were negatively correlated with infarct volume (r = −0.521) and the initial National Institutes of Health Stroke Scale score (r = −0.489). SDF-1α levels (day 1: r = −0.514; day 3: r = −0.275; day 7: r = −0.375) and circulating CD34+CXCR4+ cells (day 7: r = −0.282) were inversely associated with the 90-day modified Rankin Scale score.ConclusionThe SDF-1α/CXCR4 axis has potential applications for predicting the clinical outcome of AIS.

Spherical silica nanoparticles promote malignant transformation of BEAS-2B cells by stromal cell-derived factor-1α (SDF-1α).

ObjectiveThis study aimed to examine the role of spherical silica nanoparticles (SiNPs) on human bronchial epithelial (BEAS-2B) cells through inflammation.MethodsHuman mononuclear (THP-1) cells and BEAS-2B cells were co-cultured in transwell chambers and treated with 800 mmol/L benzo[a]pyrene-7, 8-dihydrodiol-9, 10-epoxide (BPDE) and 12.5 µg/mL SiNPs for 24 hours. For controls, cells were treated with BPDE alone. Subcutaneous tumorigenicity and epithelial-mesenchymal transition (EMT) of BEAS-2B cells were measured. The cells were blocked with a stromal cell-derived factor-1α (SDF-1α)-specific antibody. EMT was analyzed in cells treated with 800 mmol/L BPDE and 12.5 µg/mL SiNPs relative to matched control cells and xenografts in vivo. Serum SDF-1α levels were measured in 23 patients with lung adenocarcinoma in Xuanwei, in 25 with lung adenocarcinoma outside Xuanwei, and in 22 with benign pulmonary lesions in Xuanwei.ResultsSiNPs significantly promoted tumorigenesis and EMT, induced the release of SDF-1α, and activated AKT (ser473) in BEAS-2B cells. EMT and phosphorylated AKT (ser473) and glycogen synthase kinase-3β levels were decreased when blocked by SDF-1α antibody in BEAS-2B cells. SDF-1α was mainly secreted by THP-1 cells.ConclusionSiNPs combined with BPDE promote EMT of BEAS-2B cells via the AKT pathway by inducing release of SDF-1α from THP-1 cells.

11,12 and 14,15 epoxyeicosatrienoic acid rescue deteriorated wound healing in ischemia.

IntroductionEpoxyeicosatrienoic acids (EETs) are able to enhance angiogenesis and regulate inflammation that is especially important in wound healing under ischemic conditions. Thus, we evaluated the effect of local EET application on ischemic wounds in mice.MethodsIschemia was induced by cautherization of two of the three supplying vessels to the mouse ear. Wounding was performed on the ear three days later. Wounds were treated either with 11,12 or 14,15 EET and compared to untreated control and normal wounds. Epithelialization was measured every second day. VEGF, TNF-α, TGF-β, matrix metalloproteinases (MMP), tissue inhibitors of metalloproteinases (TIMP), Ki67, and SDF-1α were evaluated immunohistochemically in wounds on day 3, 6, and 9.ResultsIschemia delayed wound closure (12.8 days ± 1.9 standard deviation (SD) for ischemia and 8.0 days ± 0.94 SD for control). 11,12 and14,15 EET application ameliorated deteriorated wound healing on ischemic ears (7.6 ± 1.3 SD for 11,12 EET and 9.2 ± 1.4 SD for 14,15 EET). Ischemia did not change VEGF, TNF-α, TGF-β, SDF-1α, TIMP, MMP7 or MMP9 level significantly compared to control. Local application of 11,12 as well as 14,15 EET induced a significant elevation of VEGF, TGF-β, and SDF-1α expression as well as proliferation during the whole phase of wound healing compared to control and ischemia alone.ConclusionIn summary, EET improve impaired wound healing caused by ischemia as they enhance neovascularization and alter inflammatory response in wounds. Thus elevating lipid mediator level as 11,12 and 14,15 EET in wounds might be a successful strategy for amelioration of deranged wound healing under ischemia.

Sitagliptin and shock wave-supported peripheral blood derived endothelial progenitor cell therapy effectively preserves residual renal function in chronic kidney disease in rat—role of dipeptidyl peptidase 4 inhibition

This study tested whether sitagliptin and shock wave (SW)-assisted circulatory-derived autologous endothelial progenitor cell (EPC) therapy would effectively preserve residual renal function in chronic kidney disease (CKD) induced by 5/6 left-nephrectomy/remove right kidney plus daily feeding high-protein diet (HPD) in rat. Adult-male SD rats (n = 40) were categorized into group 1 (sham-operated control with HPD), group 2 (HPD-CKD), group 3 [HPD-CKD + EPC (1.2 × 106 cell)/intra-vessel administration by day 14 after CKD-induction], group 4 [HPD-CKD + SW (0.12 mJ/mm2/180 shorts) at days 14/21/28 after CKD-induction by ultrasound-guided application] and group 5 [HPD-CKD + SW + EPC + sitagliptin (Sita; 600 mg/kg/day since day 14 after CKD induction)]. All animals were euthanized by day 60. By day 60, renal blood flow (RBF) was highest in group 1 and progressively increased from groups 2 to 5, whereas the levels of creatinine/BUN/proteinuria exhibited an opposite pattern of RBF among the five groups (all p < 0.001). The circulating levels of GLP-1/SDF-1α and protein levels of angiogenesis (VEGF/SDF-1α/CXCR4) and GLP-1R in kidney were progressively increased from groups 1 to 5, whereas circulating DPP4 activity exhibited an opposite pattern of SDF-1α among the groups (all p < 0.0001). The protein expressions of oxidative-stress (NOX-1/NOX-2/oxidized protein), apoptosis (Bax/caspase-3/PARP), fibrosis (Smad3/TGF-ß) and inflammation (TNF-α/NF-κB/MMP-2) and kidney injury score displayed an opposite pattern, whereas the protein expressions of TMP2, endothelial-cell markers (CD31/eNOS) and podocyte integrity biomarkers (podocin/ZO-1/synaptopodin) exhibited an identical pattern of RBF among the groups (all p < 0.001). In conclusion Sita associated SW-assisted EPC effectively protected residual renal function in CKD.

Evaluation the effect of testosterone on the number of endothelial progenitor cells and amount of SDF-1α, PDGF, bFGF, and NO.

Background:Recent therapeutic advances in cardiovascular disease, thanks to the discovery of endothelial progenitor cells (EPCs). Stromal cell-derived factor-1α (SDF-1α), platelet-derived growth factor (PDGF), basic fibroblast growth factor (bFGF), and nitric oxide (NO) play a role in migration, homing, and differentiation of EPCs into mature endothelial cells. The incidence of cardiovascular disease is higher in men than in women. This fact suggests the influence of sex hormones on incidence of cardiovascular disease.Methods:Twenty-four female wistar rats weighing 160–180 g were randomly divided into four groups (N = 6): 1. sham-treated by sesame oil, 2. ovariectomized (OVX)-treated by sesame oil, 3. OVX-treated by 10 μg/kg/day testosterone, and 4. OVX-treated by 100 μg/kg/day testosterone. After 21 days, the animals were euthanized and blood samples were saved for determination of EPC count and serum levels of SDF-1α, PDGF, bFGF, and NO production.Results:High-dose testosterone induced significant increase in EPC count in OVX rats (P < 0.05). Also 100 μg/kg/day testosterone increased serum level of SDF-1α more than OVX-treated by 10 μg/kg/day testosterone (P < 0.05). But 10 μg/kg/day testosterone increased significantly the serum level of PDGF >100 μg/kg/day testosterone-treated group (P < 0.05). The serum level of bFGF in sham-treated by sesame oil was equal with its concentration in OVX-treated by 100 μg/kg/day testosterone. And the serum concentration of NO production in testosterone-treated groups were significantly less than other groups (P < 0.05).Conclusions:This study suggests that testosterone might be effective on cardiovascular disease in females by increasing EPC count through SDF-1α and PDGF mechanisms which are some of the vascular healing factors.

Involvement of stromal cell-derived factor-1α (SDF-1α), stem cell factor (SCF), fractalkine (FKN) and VEGF in TSG protection against intimal hyperplasia in rat balloon injury

BackgroundIntimal hyperplasia is the major therapeutic concern after percutaneous coronary intervention. The aim of this study is to investigate effects of 2,3,4′,5-tetrahydroxystilbene-2-O-β-D glucoside (TSG) on intimal hyperplasia and the underling mechanisms through attenuating the expressions of stromal cell-derived factor-1α (SDF-1α)/CXCR4, stem cell factor (SCF)/c-kit and fractalkine (FKN)/CX3CR1, and through promoting re-endothelialization with vascular endothelial growth factor (VEGF). MethodRats were operated with carotid artery balloon injury. The treatment groups were gavaged with 50 and 100 mg/kg/d of TSG. After 10 days of treatment, carotid artery pathological changes were evaluated by histology. Serum levels of SDF-1α, SCF, FKN and VEGF were detected by enzyme linked immunosorbent assay. The protein expressions of the receptors c-kit, CXCR4, CX3CR1, as well as CD34 and proliferating cell nuclear antigen (PCNA) were detected by immunochemistry. ResultsTSG dose-dependently inhibited balloon injury-induced intimal hyperplasia, as evidenced by reducing neointima area (NIA), neointima area/media area (NIA/MA), neointima area/internal elastic area (NIA/IELA), and by decreasing the protein expression of PCNA. TSG reduced serum levels of SDF-1α, SCF and FKN, and it also decreased the expressions of the corresponding receptors c-kit, CXCR4, CX3CR1 in neointima. Importantly, the level of VEGF in peripheral blood and the expression of CD34 in vascular walls were increased to promote re-endothelialization. ConclusionsThis study clearly demonstrated that TSG was effective in inhibiting intimal hyperplasia, and this effect was mediated, at least in part, through the SCF/c-kit, SDF-1α/CXCR4 and FKN/CX3CR1 axes. Importantly, TSG could increase VEGF and CD34 to promote endothelial repair.

Correlation between expressions of stromal cell-derived factor 1α and osteoprotegerin and bone disease in multiple myeloma

Objective To understand the correlation of expression levels of serum stromal cell-derived factor 1α (SDF-1α), osteoprotegerin (OPG) and β2 microglobulin (β2-MG) in patients with multiple myeloma (MM) with or without myeloma bone disease (MBD). Methods Eighty patients with MM who were admitted to the Affiliated Hospital of Inner Mongolia Medical University from January 2014 to June 2017 were selected; all of the patients met the international diagnostic criteria for MM. According to the symptoms such as bone pain, the patients were divided into group with MBD (45 cases) and group without MBD (35 cases). Enzyme-linked immunosorbent assay (ELISA) was used to detect the serum levels of SDF-1α and OPG, and radioimmunoassay was used to detect the expression of MM major prognostic indicator β2-MG. The MBD score was evaluated in 45 patients selected by random number table after sacroiliac joint X-ray and three-dimensional bone reconstruction. The χ 2 test was used to compare the categorical variables; the two independent sample t-test was used to compare the continuous variables that conformed to the normal distribution between two groups, and the Pearson method was used for the correlation analysis. Results The expression level of serum SDF-1α in the group with MBD was significantly higher than that in the group without MBD [0.31±0.17) pg/ml vs. (0.18±0.06) pg/ml], and the difference was statistically significant (t=-4.21, P < 0.001). The expression level of serum OPG in the group with MBD was significantly lower than that in the group without MBD [(0.73±0.50) pg/ml vs. (1.08±0.31) pg/ml], and the difference was statistically significant (t= 3.62, P < 0.001). Pearson analysis showed that β2-MG level in the group was positively correlated with SDF-1α level (r= 0.84, P < 0.001), and negatively correlated with OPG level (r=-0.48, P < 0.001). The β2-MG level in the group without MBD did not show a correlation with the SDF-1α and OPG levels. Conclusions In the serum of patients with MBD, the expression levels of β2-MG and SDF-1α are increased, and the expression level of OPG is decreased. SDF-1α and OPG may be new clinical biochemical indicators for diagnosis, treatment and prognosis assessment in MBD. Key words: Multiple myeloma; Myeloma bone disease; Stromal cell-derived factor; Osteoprotegerin; β2 microglobulin

Effects of bone marrow mesenchymal stem cell transplantation on the expression of stromal cell-derived factor-1α and vascular endothelial growth factor in rats with acute hepatic failure

Objective: To investigate the curative effect of bone marrow mesenchymal stem cells (BMSCs) transplantation on the expression of stromal cell-derived growth factor (SDF-1 α) and vascular endothelial growth factor (VEGF) in rats with acute hepatic failure, and to compare the effects of two transplantation pathways. Methods: Eighty-four rats with acute liver failure (ALF) induced by D-galactosamine combined with lipopolysaccharide were randomly divided into control group, tail vein and portal vein transplantation group. The latter two groups were injected allogenic BMSCs into the tail vein and portal vein. Blood samples and liver tissue samples were collected at 24, 72, 120, and 168h after transplantation to detect serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST). The improvement of liver function before and after BMSCs transplantation was compared. The expression of VEGF and SDF-1a in liver tissue was detected by immunofluorescence and Western blot. Data measurement between two groups was performed by analysis of variance and the correlation analysis was performed by Spearman's rank correlation coefficient. Results: Serum ALT and AST levels in the tail vein and portal vein transplantation group peaked at 24 h after transplantation, which were (134.60 ± 58.08 IU/L), (179.20 ± 86.68 IU/L), and (131.00 ± 54.47 IU/L), (173.50 ± 93.10 IU/L). In addition, 168h after transplantation it decreased to (46.10 ± 8.40 IU/L), (95.67 ± 13.80 IU/L) and (19.30 ± 1.30 IU/L), (54.30 ± 6.00 IU/L). After 120 and 168 hours of BMSCs transplantation, the levels of serum ALT and AST in tail vein and portal vein transplantation group were significantly higher than control group (F ≥ 12.51, P < 0.01). The results of western blot and immunofluorescence showed that the expression levels of SDF-1α and VEGF protein in the two BMSCs transplantation groups increased with the improvement of liver function, and the difference was statistically significant at 120 and 168 hours after transplantation (F ≥ 9.069, P < 0.05). There was no significant difference in the expression of SDF-1a and VEGF between the tail vein and portal vein transplantation groups (P > 0.05). Correlation analysis showed that the expression levels of SDF-1α and VEGF in liver tissues were positively correlated (r = 0.923, P < 0.05). Conclusion: BMSCs transplantation can promote the secretion of VEGF for recovery of liver function to reduce the degree of inflammation and necrosis in rats with ALF.

Dental pulp stem cells overexpressing stromal-derived factor-1α and vascular endothelial growth factor in dental pulp regeneration.

The current study aimed to investigate the effects of vascular endothelial growth factor (VEGF) and stromal cell-derived factor-1α (SDF-1α) overexpressing dental pulp stem cells (DPSCs) in vascularized dental pulp regeneration in vivo. Human DPSCs were transfected with VEGF or SDF-1α using premade lentiviral particles. Overexpression was verified by quantitative polymerase chain reaction (q-PCR), enzyme-linked immunosorbent assay (ELISA), and western blot analysis. Effects of SDF-1α and VEGF overexpressing DPSCs on their proliferation (CCK-8 and MTT assays) and endothelial vascular-tube formation (Matrigel assay) were investigated in vitro. Human tooth roots sectioned into 6-mm segments were injected with gene-modified DPSCs encapsulated in PuraMatrix hydrogel and implanted in the dorsum of severe-combined-immunodeficient (SCID) mice. Implants were retrieved after 4weeks and examined for regenerated pulp-like tissue and vascularization using histology and immunohistochemistry. p < 0.05 was considered statistically significant. Gene-modified DPSCs expressed significantly high levels (p < 0.05) of SDF-1α and VEGF mRNA and proteins, respectively. Transfected DPSCs showed a significantly higher cell proliferation compared to that of wild-type DPSCs. Furthermore, they enhanced endothelial cell migration and vascular-tube formation on Matrigel in vitro. When injected into tooth root canals and implanted in vivo, DPSCs/SDF-1α + DPSCs/VEGF-mixed group resulted in significantly increased length of regenerated pulp-like tissue within the root canals compared to that of wild-type DPSCs/VEGF and DPSCs/SDF-1α groups. Vessel area density was significantly higher in DPSCs/SDF-1α and mixed DPSCs/SDF-1α + DPSCs/VEGF groups than in DPSCs-VEGF alone or wild-type DPSCs groups. A combination of VEGF-overexpressing and SDF-1α-overexpressing DPSCs could enhance the area of vascularized dental pulp regeneration in vivo. Enhancing vascularization in pulp regeneration is crucial to overcome the clinical limitation of the limited blood supply to the root canals via a small apical foramen enclosed by hard dentin.

Improving the Angiogenic Potential of EPCs via Engineering with Synthetic Modified mRNAs

The application of endothelial progenitor cells (EPCs) for the revascularization of ischemic tissues, such as after myocardial infarction, stroke, and acute limb ischemia, has a huge clinical potential. However, the low retention and engraftment of EPCs as well as the poor survival of migrated stem cells in ischemic tissues still hamper the successful clinical application. Thus, in this study, we engineered, for the first time, murine EPCs with synthetic mRNAs to transiently produce proangiogenic factors vascular endothelial growth factor-A (VEGF-A), stromal cell-derived factor-1α (SDF-1α), and angiopoietin-1 (ANG-1). After the transfection of cells with synthetic mRNAs, significantly increased VEGF-A, SDF-1α, and ANG-1 protein levels were detected compared to untreated EPCs. Thereby, mRNA-engineered EPCs showed significantly increased chemotactic activity versus untreated EPCs and resulted in significantly improved attraction of EPCs. Furthermore, ANG-1 mRNA-transfected EPCs displayed a strong wound-healing capacity. Already after 12 hr, 94% of the created wound area in the scratch assay was closed compared to approximately 45% by untreated EPCs. Moreover, the transfection of EPCs with ANG-1 or SDF-1α mRNA also significantly improved the in vitro tube formation capacity; however, the strongest effect could be detected with EPCs simultaneously transfected with VEGF-A, SDF-1α, and ANG-1 mRNA. In the in vivo chicken chorioallantoic membrane (CAM) assay, EPCs transfected with ANG-1 mRNA revealed the strongest angiogenetic potential with significantly elevated vessel density and total vessel network length. In conclusion, this study demonstrated that EPCs can be successfully engineered with synthetic mRNAs encoding proangiogenic factors to improve their therapeutic angiogenetic potential in patients experiencing chronic or acute ischemic disease.

Circulating Progenitor Cells and Racial Differences.

Blacks compared with whites have a greater risk of adverse cardiovascular outcomes. Impaired regenerative capacity, measured as lower levels of circulating progenitor cells (CPCs), is a novel determinant of adverse outcomes; however, little is known about racial differences in CPCs. To investigate the number of CPCs, PC-mobilizing factors, PC mobilization during acute myocardial infarction and the predictive value of CPC counts in blacks compared with whites. CPCs were enumerated by flow cytometry as CD45med+ blood mononuclear cells expressing CD34+, CD133+, VEGF2R+, and CXCR4+ epitopes in 1747 subjects, mean age 58.4±13, 55% male, and 26% self-reported black. Patients presenting with acute myocardial infarction (n=91) were analyzed separately. Models were adjusted for relevant clinical variables. SDF-1α (stromal cell-derived factor-1α), VEGF (vascular endothelial growth factor), and MMP-9 (matrix metallopeptidase-9) levels were measured (n=561), and 623 patients were followed for median of 2.2 years for survival analysis. Blacks were younger, more often female, with a higher burden of cardiovascular risk, and lower CPC counts. Blacks had fewer CD34+ cells (-17.6%; [95% confidence interval (CI), -23.5% to -11.3%]; P<0.001), CD34+/CD133+ cells (-15.5%; [95% CI, -22.4% to -8.1%]; P<0.001), CD34+/CXCR4+ cells (-17.3%; [95% CI, -23.9% to -10.2%]; P<0.001), and CD34+/VEGF2R+ cells (-27.9%; [95% CI, -46.9% to -2.0%]; P=0.04) compared with whites. The association between lower CPC counts and black race was not affected by risk factors or cardiovascular disease. Results were validated in a separate cohort of 411 patients. Blacks with acute myocardial infarction had significantly fewer CPCs compared with whites ( P=0.02). Blacks had significantly lower plasma MMP-9 levels ( P<0.001) which attenuated the association between low CD34+ and black race by 19% (95% CI, 13%-33%). However, VEGF and SDF-1α levels were not significantly different between the races. Lower CD34+ counts were similarly predictive of mortality in blacks (hazard ratio, 2.83; [95% CI, 1.12-7.20]; P=0.03) and whites (hazard ratio, 1.79; [95% CI, 1.09-2.94]; P=0.02) without significant interaction. Black subjects have lower levels of CPCs compared with whites which is partially dependent on lower circulating MMP-9 levels. Impaired regenerative capacity is predictive of adverse outcomes in blacks and may partly account for their increased risk of cardiovascular events.

Immunological effects of a low-dose cytarabine, aclarubicin and granulocyte-colony stimulating factor priming regimen on a mouse leukemia model.

The low-dose cytarabine, aclarubicin and granulocyte-colony stimulating factor (G-CSF) (CAG) priming regimen is an effective treatment for patients with relapsed or refractory acute myeloid leukemia (AML) and advanced myelodysplastic syndrome (MDS). G-CSF influences the bone marrow microenvironment (BMM) by mobilizing regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs), as well as by reducing the expression of stromal cell-derived factor-1α (SDF-1α). In the present study, a WEHI-3-grafted BALB/c mouse AML model (AML-M4) was employed to determine how the BMM was altered by different treatment regimens. It was evident that CAG regimen decreased and increased the proportion of Tregs and MDSCs in the bone marrow and spleen, respectively. Furthermore, the CAG regimen downregulated SDF-1α levels in the bone marrow and peripheral blood. However, hematoxylin and eosin staining of the main organs revealed that leukemic cells infiltrated the liver following treatment with the CAG regimen. The present study indicates that the CAG regimen has a positive effect on the immunosuppressive microenvironment in AML and relieves AML-associated BMM immune suppression by decreasing Tregs and MDSCs in the bone marrow and downregulating the SDF-1α/CXCR4 axis in the bone marrow and peripheral blood.

The Effect of Gliptins to Improve Functional Outcome after Stroke in Mice Is Mediated by the CXCR4/SDF-1α Pathway

Dipeptidyl peptidase-4 (DPP-4) inhibitors (gliptins) decrease hyperglycemia by inhibiting glucagon-like peptide-1 (GLP-1) cleavage. Gliptins can also improve stroke outcome in rodents independently of GLP-1R. However, the underlying mechanisms are unknown. Stromal cell-derived factor-1α (SDF-1α) is a DPP-4 substrate and CXCR4 agonist that promotes beneficial effects in injured brains. However, SDF-1α involvement in gliptin-mediated neuroprotection is unproven. We aimed to determine whether gliptins improve stroke outcome via SDF-1α/CXCR4 and identify additional targets behind the efficacy. Adult, male C57bl6/j mice (n=101) underwent transient focal cerebral ischemia. Linagliptin was administered for 3 days or 3 weeks. The CXCR4-antagonist AMD3100 was administered starting a day before ischemia. Stroke outcome was assessed by measuring upper-limb function and brain tissue damage. Levels of active GLP-1, gastric inhibitory polypeptide (GIP) and SDF-1α were quantified by ELISA in serum and brain. Mass spectrometry was used to identify additional gliptin-mediated effectors in brain tissue samples. Sustained, post-ischemic treatment with linagliptin reduced motor impairment (p003C0.01) and tissue damage (p003C0.05). Linagliptin increased serum levels of GLP-1 (p003C0.0001), GIP (p003C0.05) and SDF-1α (p003C0.05). However, only SDF-1α levels were increased in the brain (p003C0.001). Linagliptin also decreased the presence of neurogranin-derived peptides and peptides from an isoform of myelin basic protein (MBG, p003C0.05). The inhibition of SDF-1α/CXCR4 pathway diminished the positive effects of linagliptin on stroke outcome (not different from vehicle). We propose a gliptin-mediated neuroprotective mechanism via SDF-1α, which could affect Ca2+ homeostasis, altering neurogranin and MBG processing and potentially decreasing calpain activity. These results provide new insights into restorative gliptin-mediated effects against stroke. Disclosure F. Chiazza: Other Relationship; Self; Boehringer Ingelheim GmbH. H. Tammen: Consultant; Self; Boehringer Ingelheim GmbH. H. Pintana: Other Relationship; Self; Boehringer Ingelheim GmbH. G. Lietzau: Other Relationship; Self; Boehringer Ingelheim GmbH. M. Collino: None. T. Nystrom: Research Support; Self; AstraZeneca. Advisory Panel; Self; Eli Lilly and Company, Novo Nordisk A/S. Speaker's Bureau; Self; Boehringer Ingelheim GmbH. T. Klein: Employee; Self; Boehringer Ingelheim GmbH. V. Darsalia: Other Relationship; Self; Boehringer Ingelheim GmbH. C. Patrone: Other Relationship; Self; Boehringer Ingelheim GmbH.

Intraperitoneal infusion of mesenchymal stem cell attenuates severity of collagen antibody induced arthritis.

It is unclear how systemic administration of mesenchymal stem cells (MSCs) controls local inflammation. The aim of this study was to evaluate the therapeutic effects of human MSCs on inflammatory arthritis and to identify the underlying mechanisms. Mice with collagen antibody-induced arthritis (CAIA) received two intraperitoneal injections of human bone marrow-derived MSCs. The clinical and histological features of injected CAIA were then compared with those of non-injected mice. The effect of MSCs on induction of regulatory T cells was examined both in vitro and in vivo. We also examined multiple cytokines secreted by peritoneal mononuclear cells, along with migration of MSCs in the presence of stromal cell-derived factor-1 alpha (SDF-1α) and/or regulated on activation, normal T cell expressed and secreted (RANTES). Sections of CAIA mouse joints and spleen were stained for human anti-nuclear antibodies (ANAs) to confirm migration of injected human MSCs. The results showed that MSCs alleviated the clinical and histological signs of synovitis in CAIA mice. Peritoneal lavage cells from mice treated with MSCs expressed higher levels of SDF-1α and RANTES than those from mice not treated with MSCs. MSC migration was more prevalent in the presence of SDF-1α and/or RANTES. MSCs induced CD4+ T cells to differentiate into regulatory T cells in vitro, and expression of FOXP3 mRNA was upregulated in the forepaws of MSC-treated CAIA mice. Synovial and splenic tissues from CAIA mice receiving human MSCs were positive for human ANA, suggesting recruitment of MSCs. Taken together, these results suggest that MSCs migrate into inflamed tissues and directly induce the differentiation of CD4+ T cells into regulatory T cells, which then suppress inflammation. Thus, systemic administration of MSCs may be a therapeutic option for rheumatoid arthritis.