Increase of circulating stromal cell-derived factor-1 in heart failure patients

Association of serum stromal cell-derived factor 1 levels with EZSCAN score and its derived indicators in patients with type 2 diabetes

BACKGROUND

The aim of the study was to explore whether plasma stromal cell-derived factor 1 (SDF-1) levels are associated with the EZSCAN score and its derived indicators in patients with type 2 diabetes (T2D).

METHODS

From July 2020 to December 2020, a total of 253 patients with T2D were consecutively recruited. Serum SDF-1 levels were measured by sandwich ELISA. EZSCAN test was applied to evaluate the sudomotor function of each patient, and based on the results, EZSCAN score, cardiac autonomic neuropathy risk score (CANRS) and cardiovascular risk score (CVDRS) were calculated by particular algorithms. In addition, other relevant clinical data were also collected.

RESULTS

With increasing tertiles of serum SDF-1 levels, the CANRS and CVDRS significantly increased (both Pfor trend <0.001), while the EZSCAN score significantly decreased (Pfor trend <0.001). Moreover, serum SDF-1 levels were significantly and positively correlated with the CANRS and CVDRS (r = 0.496 and 0.510, respectively, both P < 0.001), and negatively correlated with the EZSCAN score (r = -0.391, P < 0.001). Furthermore, multivariate linear regression analyses were constructed, and after adjusting for other clinical covariates, serum SDF-1 levels were independently responsible for EZSCAN score (β = -0.273, t = -3.679, P < 0.001), CANRS (β = 0.334, t = 5.110, P < 0.001) and CVDRS (β = 0.191, t = 4.983, P = 0.003).

CONCLUSIONS

SDF-1 levels in serum were independently associated with the EZSCAN score and its derived indicators, such as CANRS and CVDRS in patients with T2D.

Hair follicle stem cells promote cutaneous wound healing through the SDF-1α/CXCR4 axis: an animal model

OBJECTIVE

An appropriate source of adult stem cells for therapeutic use is stem cells deriving from the hair follicle bulge. Following injury, ischaemic tissues produce a variety of cytokines and growth factors that are essential for tissue repair. This study sought to investigate the temporal effects of hair follicle bulge stem cells (HFSCs) on cutaneous wound healing in rats using the SDF-1α/CXCR4 axis.

METHOD

HFSCs obtained from rat vibrissa, labeled with DiI and then special markers, were detected using flow cytometry. The animals were divided into five groups: control (non-treated, n=18), sham (PBS, n=18), AMD (treated with AMD3100, n=18), HFSC + AMD (treated with HFSCs + AMD3100, n=18) and HFSC (treated with HFSCs, n=18). A full-thickness excisional wound model was created and DiI-labeled HFSCs were injected around the wound bed. Wound healing was recorded with digital photographs. The animals were sacrificed 3, 7 and 14 days after the surgery and were used for histological (H&E, Masson's trichrome staining) and molecular (ELISA and q-PCR) assays.

RESULTS

The flow cytometry results demonstrated that HFSCs were CD34-positive, nestin-positive, but Kr15-negative. The morphological analysis of the HFSC-treated wounds showed accelerated wound closure. The histological analysis of the photomicrographs exhibited more re-epithelialisation and dermal structural regeneration in the HFSC-treated wounds compared with the control group. In the HFSC + AMD group, the histological parameters improved on the same days, but showed a significant decrease compared with the HFSC group in all the days assayed. In the AMD group, there was a significant reduction in the noted parameters. qRT-PCR and ELISA showed a high expression level of SDF-1α, CXCR4 and VEGFR-2 in the HFSC-treated wounded skin tissue, but the expression of CXCR4 and VEGFR-2 showed a significant reduction in the HFSC + AMD group compared with the HFSC group.

CONCLUSIONS

Based on the findings of this study, HFSC transplantation affects wound closure parameters and the expression of SDF-1α and CXCR4. As the SDF-1α expression level increases in the injured area, the HFSCs contribute to wound repair through the SDF-1α/CXCR4 axis. This result is extremely valuable because it raises the possibility of wounds healed by isolating autologous HFSCs from the patient.

Acetaldehyde dehydrogenase 2 deficiency exacerbates cardiac fibrosis by promoting mobilization and homing of bone marrow fibroblast progenitor cells

Cardiac fibrosis is a common feature of various cardiovascular diseases. Previous studies showed that acetaldehyde dehydrogenase 2 (ALDH2) deficiency exacerbated pressure overload-induced heart failure. However, the role and mechanisms of cardiac fibrosis in this process remain largely unknown. This study aimed to investigate the effect of ALDH2 deficiency on cardiac fibrosis in transverse aortic constriction (TAC) induced pressure overload model in mice. Echocardiography and histological analysis revealed cardiac dysfunction and enhanced cardiac fibrosis in TAC-operated animals; ALDH2 deficiency further aggravated these changes. ALDH2 chimeric mice were generated by bone marrow (BM) transplantation of WT mice into the lethally irradiated ALDH2KO mice. The proportion of circulating fibroblast progenitor cells (FPCs) and ROS level in BM after TAC were significantly higher in ALDH2KO mice than in ALDH2 chimeric mice. Furthermore, FPCs were isolated and cultured for in vitro mechanistic studies. The results showed that the stem cell-derived factor 1 (SDF-1)/C-X-C chemokine receptor 4 (CXCR4) axis played a major role in the recruitment of FPCs. In conclusion, our research reveals that increased bone marrow FPCs mobilization and myocardial homing contribute to the enhanced cardiac fibrosis and dysfunction induced by TAC in ALDH2 KO mice via exacerbating accumulation of ROS in BM and myocardial SDF-1 expression.

Preliminary Study of Bone Marrow-Derived Mesenchymal Stem Cells Pretreatment With Erythropoietin in Preventing Acute Rejection After Rat Renal Transplantation

Renal transplantation is currently the most effective treatment for end-stage kidney diseases, and acute allograft rejection is well treated with high dose prednisolone and immunosuppressive agents, but long-term use of immunosuppressants will be detrimental to the long-term survival of the transplanted kidney and will have many side effects on the human body. Thus, a local and alloantigen-specific immunological tolerance may be a promising approach to improving kidney transplantation. The aim of this study is to examine the therapeutic potential of transforming bone marrow-derived mesenchymal stem cells (BMSCs) pretreated with erythropoietin (EPO) in inducing immunosuppression in renal grafts after transplantation. The immunity suppression effects were tested, focusing on the decrease of serum creatinine and the cells' ability to regulate the expression of the cytokines associated with acute rejection. Our findings demonstrate that a transfusion of BMSCs pretreated with EPO (EPO-BMSCs) can produce an immunosuppressive effect and reduce the occurrence of acute rejection. Their reciprocal effects on the induction and function of regulatory T cells (Tregs) resulted in the balance of IFN-γ/IL-4 and improved immunosuppressive effects in local kidney grafts. Our data also suggest that the acute rejection microenvironment had a directional chemotactic effect on BMSCs, which is related to the upregulation of CXCR4, and could be further enhanced by EPO treatment. Thus, transfusion of EPO-BMSCs can induce a greater local immunosuppressive effect in renal grafts after transplantation compared with untreated BMSCs. Therefore, transplantation with EPO-BMSCs can be a novel and effective approach to lower the acute rejection ratio following transplantation.

A novel recombinant antibody specific to full-length stromal derived factor-1 for potential application in biomarker studies

Background

Stromal derived factor-1α (SDF-1α/CXCL12) is a chemokine that is up-regulated in diseases characterised by tissue hypoxia, including myocardial infarction, ischaemic cardiomyopathy and remote ischaemic conditioning (RIC), a technique of cyclical, non-injurious ischaemia applied remote from the heart that protects the heat from lethal ischaemia-reperfusion injury. Accordingly, there is considerable interest in SDF-1α as a potential biomarker of such conditions. However, SDF-1α is rapidly degraded and inactivated by dipeptidyl peptidase 4 and other peptidases, and the kinetics of intact SDF-1α remain unknown.

Methods & results

To facilitate investigation of full-length SDF-1α we established an ELISA using a novel recombinant human antibody we developed called HCI.SDF1. HCI.SDF1 is specific to the N-terminal sequence of all isoforms of SDF-1 and has a comparable K_D to commercially available antibodies. Together with a detection antibody specific to the α-isoform, HCI.SDF1 was used to specifically quantify full-length SDF-1α in blood for the first time. Using RIC applied to the hind limb of Sprague-Dawley rats or the arms of healthy human volunteers, we demonstrate an increase in SDF-1α using a commercially available antibody, as previously reported, but an unexpected decrease in full-length SDF-1α after RIC in both species.

Conclusions

We report for the first time the development of a novel recombinant antibody specific to full-length SDF-1. Applied to RIC, we demonstrate a significant decrease in SDF-1α that is at odds with the literature and suggests a need to investigate the kinetics of full-length SDF-1α in conditions characterised by tissue hypoxia.