Isolation of putative progenitor endothelial cells for angiogenesis

Effect of BMSCs overexpressing intelectin-1 on angiogenesis in rats with cerebral infarction

Background

Cerebral infarction (CI) is a common and frequently occurring acute neurological disease in clinical practice, posing a severe threat to human health. CI results from various causes leading to local cerebral tissue ischemia and hypoxia due to vascular occlusion and impaired blood supply, which in turn leads to tissue necrosis and corresponding clinical manifestations of neurological deficits. However, to date, treatment options for cerebral infarction remain limited. Therefore, it is crucial to rapidly establish collateral circulation to compensate for the occluded vessels and restore blood flow perfusion.

Objective

To assess the effect of bone marrow mesenchymal cells transfected with intelectin-1 (Itln-1) gene on the angiogenesis and apoptosis of CI.

Method

Lentiviral-mediated transfection of the Itln-1 gene into bone marrow mesenchymal stem cells (BMSCs) was performed, followed by intravenous injection into rats with CI through the tail vein. The volume of the CI, capillary density, and apoptotic cells were detected.

Results

With the increase of AKT and eNOS phosphorylation levels, BMSCs with overexpression Itln-1 gene could significantly promote angiogenesis and reduce the infarct volume in the ischemic penumbra. Meanwhile, the ratio of Bcl-2/Bax increased, and apoptotic cells decreased.

Conclusion

The overexpression of Itln-1 can effectively promote CI angiogenesis and inhibit cell apoptosis than transplantation of Itln-1 gene or MSCS alone.

Circulating CD34-positive cells are associated with prolonged time to fracture in people with Duchenne muscular dystrophy on chronic glucocorticoids

Glucocorticoids decrease preosteoclast (POC) platelet-derived-growth-factor-type-BB (PDGF-BB), reducing migration of endothelial and osteo-progenitor cells, impairing skeletal angiogenesis and osteogenesis in mice. To explore human translation, we conducted a case-control study on Duchenne muscular dystrophy (DMD) youth treated with chronic glucocorticoids (n=24) relative to healthy controls (n=13) to explore the association of PDGF-BB, VEGF, angiogenin concentration and peripheral blood mononuclear cell (PBMC) subpopulations as surrogates of POCs (CD14+/Stro-1-/CD105-), skeletal progenitor cells (SPCs: Stro-1+/CD105+/CD14-/CD45-), and endothelial/hematopoietic progenitor cells (CD34+/CD14-/Stro-1-/CD105-) and CE140b mean fluorescence intensity (MFI) to fracture. People with DMD (8-20 years), were stratified by prior and subsequent fractures relative to biospecimen collection. Healthy controls were age- and sex-matched. Differences between groups were assessed with one-way ANOVA with post-hoc Tukey's test, retrospective fractures by Kendall Tau correlation, and prospective fractures by bivariable and multivariable accelerated time failure models. Baseline characteristics between groups were similar, though people with DMD were shorter relative to healthy controls, and in the DMD groups, those with prior fractures had a longer duration of glucocorticoid therapy. We noted decreased PDGF-BB concentration and percentages of circulating POCs, SPCs, and CD34+ cells in people with DMD relative to healthy controls. Circulating CD34+ cell percentage positively correlated with PDGF-BB concentration, similar to murine models. Lower percentage of circulating SPCs and CD140b MFI was associated with increased number of retrospective fractures. After a mean follow-up of 2.23 yr, 79% of people with DMD sustained a subsequent fracture. Higher PDGF-BB concentration and percent of POC, SPCs, and CD34+ cells were associated with a longer time to next fracture. After controlling for covariates of fracture risk, increased percentage of CD34+ cells continued to be associated with prolonged time to fracture. Circulating CD34+ cells may thus be a potential biomarker to predict acute fracture risk in young people with DMD on chronic glucocorticoids.

Circulating Endothelial Progenitor Cells and Metabolic Factors in Childhood Cancer Survivors

BACKGROUND

Circulating endothelial progenitor cells (cEPCs) are known to have an active role in maintaining healthy vessel anatomy and function. The purpose of the present study was to quantify cEPCs in childhood cancer survivors after treatment completion and evaluate possible associations of their levels with metabolic disorders.

METHODS

Circulating EPCs isolated from peripheral blood samples from 383 children and adolescent cancer survivors diagnosed with acute lymphoblastic leukemia (ALL), lymphomas, or solid tumors (ST) were quantified 1, 3, and more than 3 years after treatment completion using flow cytometry. Their levels were compared to 200 healthy controls, and multivariate logistic regression analysis was applied to seek correlations with metabolic disorders, including hypertension, obesity, hyperglycemia, and dyslipidemia.

RESULTS

The levels of CD34+/CD133+/VEGFR+ and CD34+/VEGFR+ cEPCs were significantly higher in children treated for solid tumors and lymphomas compared to the ALL group. Compared to controls, both cEPCs populations were found to be increased in patients treated for ST (CD34+/CD133+/VEGFR+, p = 0.0049; CD34+/VEGFR+, p = 0.0001). Declining trends of CD34+/VEGFR+ and CD34+/CD133+/VEGFR+ levels were observed in patients treated for solid tumors and lymphomas during the first 3 years after treatment, while an increasing trend was observed in ALL patients (p = 0.01). Three years after treatment completion, all groups had cEPC levels comparable to the control group. By multivariate regression analysis, no significant differences were observed in children with metabolic disorders, including hypertension, obesity, hyperglycemia, and dyslipidemia.

CONCLUSION

Significant differences in cEPC levels were observed in childhood cancer survivors during the first year after treatment completion, which were comparable to healthy controls after 3 years post-treatment.

Fabricate heparin-mimic thin gel layers for vascular cell selective regulation using 5-hydroxydopamine cross-linked chitosan and sulfonated polymers

In this work, 5-hydroxydopamine was employed as a crosslinking agent to bind chitosan and sulfonated polymers to fabricate thin gel layers (TGLs) featuring heparin-mimic structures. By controlling the distribution of exposed chemical moieties (phenolic hydroxyl, amino, and sulfonic groups), the growth of the endothelial cell (EC) and smooth muscle cell (SMC) on the TGLs surfaces could be modulated. Such modulation effectively maintained the quantity and proportion of the two cell types within a reasonable range, thereby offering a potential avenue for promoting re-endothelialization. The prepared TGLs showed improved hydrophilicity as well as hemocompatibility. For cytocompatibility test, TGLs led to a notable promotion of the growth of human umbilical vein endothelial cells (HUVECs) and exerted substantial inhibitory effects on the proliferation of human umbilical artery smooth muscle cells (HUASMCs). The ratio of HUVECs to HUASMCs rose from 0.184 to 1.97. The enhanced hemocompatibility was attributed to the incorporation of exposed functional groups. Regarding the highly selective effects, these were ascribed to the synergistic influence of high sulfonation degree and the presence of amino groups and phenolic hydroxyl groups. The current work illustrated a simple method for synthesizing a multifunctional biomimetic polymer material that offers the promise of broader biomedical research applications.

Mobilization of endothelial progenitor cells after implantation of CD34 antibody-covered sirolimus-eluting COMBO® stent: assessment with EPC colony-forming assay

The COMBO® stent is a unique stent on which the CD34 antibody is mounted to capture CD34 + endothelial progenitor cells (EPCs) and from which sirolimus is eluted to suppress neointimal hyperplasia. The COMBO® stent aims to induce early re-endothelialization and vascular healing and to prevent restenosis. In the clinical setting, however, the effects of the COMBO® stent have not been validated in terms of EPC biology. In this study, we assessed the kinetics of circulating EPCs, not only quantitatively by flow cytometric analysis but also qualitatively by an EPC colony-forming assay, in 25 patients undergoing COMBO® stent implantation. Among all patients, flow cytometric analysis indicated that the number of circulating CD34 + /KDR + EPCs did not change after COMBO® stent implantation compared with baseline (before stent implantation). The EPC colony-forming assay demonstrated that the number of small-type EPC colonies increased on day 2 (3 [2, 9] to 6 [4, 9]/dish, P = 0.026) and that of large-type EPC colonies more prominently increased on day 2 (1 [0, 4] to 5 [1, 10]/dish, P < 0.001) and day 7 (to 2 [1, 7], P = 0.006) after COMBO® stent implantation. Based on the results of optical coherence tomography at 3 months after stent implantation, the patients were divided into two groups: well (uncovered strut ratio < 10%, n = 14) and poor (uncovered strut ratio ≥ 10%, n = 10) stent coverage. Compared with baseline values, the number of large-type EPC colonies increased on day 2 (2.9 ± 0.8 to 7.3 ± 2.0, P = 0.026) and tended to increase on day 7 (6.8 ± 2.0/dish, P = 0.062) after COMBO® stent implantation in the well coverage group, while it did not change in the poor coverage group. Thus, the COMBO® stent might induce mature EPCs in the circulation, which might be associated with subsequent healing processes in vessel sites with stent-induced injury.

Concentrated growth factors promote epithelization in the mastoid obliteration after canal wall down mastoidectomy

OBJECTIVE

This retrospective study aimed at comparing the extent of epithelialization in mastoid obliteration after Canal Wall Down (CWD) mastoidectomy using Hydroxyapatite (HA) alone or using HA in combination with Concentrated Growth Factor (CGF) extracted from autologous blood.

METHODS

A total of 56 patients undergoing the CWD mastoidectomy were enrolled. One group was treated by HA, while the other group received HA and CGF for mastoid obliteration (CGF/HA). A review of the medical follow-up records of all patients was conducted, with a primary focus on the otoendoscopic imaging materials. Complete epithelialization was determined by the absence of granulation, discharge, and swelling. The requisite period for complete epithelialization of the mastoid cavity was thus calculated, scored, and analyzed between treatments.

RESULTS

Ear discharge, graft swelling, and poor blood supply were more frequently observed in the HA group. The proportion of patients group that achieved complete epithelialization within 60 days post operation was significantly higher in the CGF/HA group than the HA group. According to the scoring system for complete epithelialization, the median score of the CGF/HA group was 2, significantly higher than that of the HA treatment group (median score = 1, p = 0.032). Altogether, our results indicated that duration needed for complete epithelialization in the CGF/HA group was shorter than the control group.

CONCLUSION

The application of CGF to surgical cavity obliteration following a CWD mastoidectomy significantly promotes epithelialization, thereby achieving satisfactory results. Randomized controlled trials with a larger number of patients enrolled were worth launching in the future to better substantiate the value of CGF in obliteration of mastoid cavity.

LEVEL OF EVIDENCE

Level 2-Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence.

Advancements in Gene-Based Therapeutic Angiogenesis for Chronic Limb-Threatening Ischemia

The objective of this article is to summarize the research progress and discuss the current difficulties of gene-based therapeutic angiogenesis in lower limb ischemic diseases, so as to provide new research directions for the non-invasive treatment of lower limb ischemia. The basic and clinical trials of gene-based therapeutic angiogenesis in lower limb ischemia in recent years were read and reviewed. Growth factors such as vascular endothelial growth factor, hepatocyte growth factor, and fibroblast growth factor have been extensively studied for their application in lower limb ischemic diseases. However, clinical studies across various phases have shown inconsistent efficacy endpoints. The efficacy of gene therapy remains questionable. Before exploring efficient methods of delivering pro-angiogenic genes to ischemic tissues, clarification is needed regarding whether the goal of gene therapy is to simply promote collateral circulation or create a conducive tissue microenvironment for angiogenesis. In conclusion, pre-clinical and clinical studies have demonstrated the potential of therapeutic angiogenesis, but more systematic and comprehensive research is needed to explore safer, more effective, and cost-effective treatment methods.

Comparison of Vessel Responses Following Combined Sirolimus-Eluting and Endothelial Progenitor Cell Stent and Ultra-Thin Sirolimus-Eluting Stent Implantation by Serial Optical Coherence Tomography and Coronary Angioscopy: A Multicenter Observational Study

A dual-therapy sirolimus-eluting and CD34+ antibody-coated Combo Stent (DTS) has been developed to enhance endothelization and capture endothelial progenitor cells; however, vessel responses following DTS implantation remain unclear. Therefore, we evaluated early- and mid-term intravascular characteristics of DTS using intravascular imaging modalities. This multicenter, prospective, observational study enrolled 88 patients (95 lesions) who underwent DTS (43 patients, 48 lesions) or sirolimus-eluting Orsiro stent (SES, 45 patients, 47 lesions) implantation. Serial optical coherence tomography (OCT) and coronary angioscopy (CAS) findings were compared between the groups at 1 and 12 months.The OCT findings were similar between the DTS and SES groups at 1 month, including the covered strut rate (84.21 ± 9.50% versus 80.56 ± 17.68%, p = 0.27). CAS findings were also comparable despite a more severe yellow coloration observed in the DTS group (p = 0.006). At 12 months, OCT findings revealed that the covered and adequate strut coverage (≥40 μm) rates were significantly higher (99.27 ± 0.95% versus 95.46 ± 5.56%, p <0.001 and 88.90 ± 10.15% versus 72.96 ± 16.48%, p <0.001) and neointimal thickness was significantly thicker (152.16 ± 70.31 versus 84.39 ± 29.80 μm, p <0.001) in DTS than in SES. The malapposed strut rate was significantly higher in SES than in DTS (0.04 ± 0.18% versus 0.82 ± 1.87%, p = 0.018). CAS revealed that the yellow coloration (p = 0.049) and subclinical intrastent thrombus (p = 0.019) were less severe in DTS than in SES at 12 months. In conclusion, DTS provided better advantages regarding strut coverage and plaque stabilization compared to SES. However, given the observational nature of this study, further randomized controlled trials are needed to confirm these findings.

Endothelial colony-forming cells to study bleeding or vascular malformation disorders - opportunities and limitations

Hemostasis relies on a balance between procoagulant and anticoagulant factors involving interactions among the vascular endothelium, platelets, and multiple coagulation proteins. Disturbed hemostasis can result in clinical bleeding symptoms. Widely used diagnostic laboratory assays evaluate platelet count, platelet function, and various coagulation factors present in plasma, as typically studied in patients with bleeding, whereas endothelial cell function cannot be studied in this same manner. Measuring vascular endothelium function could indirectly be done using endothelial colony-forming cells (ECFCs), but this is not an assay readily used in diagnostic laboratories. ECFCs are true endothelial progenitor cells that can be isolated from peripheral blood. They exhibit great proliferative potential to form colonies in vitro and actively participate in angiogenesis; therefore, they are an excellent ex vivo model for studying several conditions where the vascular endothelium is involved. In this review, we provide a comprehensive overview of the use of ECFCs as a disease model to study various bleeding and vascular malformation disorders. Additionally, we discuss both advantages and (future) challenges associated with the use of ECFCs.

A rapamycin-loading platelet membrane hybrid liposome with anti-inflammation effect and long-lasting repair capability for acute kidney injury

Acute kidney injury (AKI) represents a rapid decline in kidney function, often associated with significant morbidity and mortality. Inefficient management of acute-phase inflammation and inadequate repair of established damage exacerbate AKI and facilitate its progression to chronic kidney disease (CKD). Platelet membrane (PM) has emerged as a promising targeting ligand in various studies. PM proteins can also facilitate the recruitment and differentiation of CD34+ cells (hematopoietic stem cells and endothelial progenitor cells) through both direct and indirect mechanisms, including enhancing adhesion of CD34+ cells to damaged tissues and elevating stromal cell-derived factor-1 (SDF-1) levels in ischemia-reperfusion injury (IRI) kidneys. In parallel, extensive research has demonstrated that rapamycin shows high potential as an anti-inflammatory therapy for AKI. Herein, we design a PM hybrid rapamycin liposome (Rapa@PM-Lipo), which not only improves the delivery efficiency of rapamycin, but also leverages the potential of PM to achieve long-lasting repair. Rapa@PM-Lipo significantly reduced Acute renal Tubular Necrosis (ATN) score in IRI kidneys following intravenous administration, both as a single and multiple doses. This study exploits the therapeutic potential of PM and explores its novel applications for facilitating tissue repair, presenting a promising strategy for the treatment of AKI and mitigating its progression to CKD.

Caffeine improves systemic lupus erythematosus endothelial dysfunction by promoting endothelial progenitor cells survival

OBJECTIVE

We studied the role of caffeine intake on endothelial function in SLE by assessing its effect on circulating endothelial progenitor cells (EPCs) both ex vivo in SLE patients and in vitro in healthy donors (HD) treated with SLE sera.

METHODS

We enrolled SLE patients without traditional cardiovascular risks factors. Caffeine intake was evaluated with a 7-day food frequency questionnaire. EPCs percentage was assessed by flow cytometry analysis and, subsequently, EPCs pooled from six HD were co-cultured with caffeine with and without SLE sera. After 7 days, we evaluated cells' morphology and ability to form colonies, the percentage of apoptotic cells by flow cytometry analysis and the levels of autophagy and apoptotic markers by western blot. Finally, we performed a western blot analysis to assess the A2AR/SIRT3/AMPK pathway.

RESULTS

We enrolled 31 SLE patients, and observed a positive correlation between caffeine intake and circulating EPCs percentage. HD EPCs treated with SLE sera and caffeine showed an improvement in morphology and in number of EPCs colony-forming units in comparison with those incubated without caffeine. Caffeine was able to restore autophagy and apoptotic markers in HD EPCs as before SLE sera treatment. Finally, caffeine treatment was able to significantly reduce A2AR levels, leading to an increase in protein levels of SIRT3 and subsequently AMPK phosphorylation.

CONCLUSIONS

Caffeine intake positively correlated with the percentage of circulating EPCs in SLE patients; moreover, caffeine in vitro treatment was able to improve EPC survival and vitality through the inhibition of apoptosis and the promotion of autophagy via A2AR/SIRT3/AMPK pathway.

The study of miR-130a expression and its mechanism of action in peripheral blood endothelial progenitor cells (EPCs) in type 2 diabetes mellitus (T2DM)

TGF-β1 has been reported to suppress miR-130a expression, while being elevated in patients with type 2 diabetes mellitus (T2DM). And IL-18, a potential target of miR-130a, is also up-regulated in T2DM patients. In this study, we aim to investigate the potential involvement of the TGFβ1/miR-130a/IL-18 axis underlying the dysfunction of endothelial progenitor cells (EPCs) in T2DM patients. We performed luciferase assays to confirm the molecular binding between miR-130a, TGF-β1 and IL-18, and real-time PCR and ELISA were performed to observe the changes of TGF-β1, miR-130a, IL-18 and IFN-γ in different cell groups. Tube formation assay, cell adhesion assay and Transwell assay were performed to evaluate effect of TGF-β1/miR-130a/IL-18 axis on the EPCs functions. Accordingly, in EPCs treated with TGF-β1, we found that the levels of miR-130a were reduced, and its expressions were also negatively correlated with the expressions of IL-18 in the EPC groups. Luciferase assays validated IL-18 as a target gene of miR-130a. The over-expression of IL-18, as well as the knockdown of miR-130a, not only increased the expressions of TGF-β1 in EPCs, but also promoted the tube formation, adhesion and migration of EPCs. By contrast, the knockdown of IL-18, as well as the over-regulation of miR-130a, exhibited suppressive effect on the levels of TGF-β1, while inhibiting the tube formation, adhesion and migration of EPCs. In this study, we elucidated the impact of the TGFβ1/miR-130a/IL-18 signaling pathway on the function of EPCs, thus providing theoretical basis for the development of miRNA-targeted therapeutic strategies for patients withT2DM and associated complications.

Blood-brain barrier disruption: a pervasive driver and mechanistic link between traumatic brain injury and Alzheimer's disease

Traumatic brain injury (TBI) has emerged as a significant risk factor for Alzheimer's disease (AD), a complex and devastating neurodegenerative disorder characterized by progressive cognitive decline and memory loss. Both conditions share a common feature: blood‒brain barrier (BBB) dysfunction, which is believed to play a pivotal role in linking TBI to the development of AD. This review delves into the intricate relationship between TBI and AD, with a focus on BBB dysfunction and its critical role in disease mechanisms and therapeutic development. We first present recent evidence from epidemiological studies highlighting the increased incidence of AD among individuals with a history of TBI, as well as pathological and animal model studies that demonstrate how TBI can accelerate AD-like pathology. Next, we explore the mechanisms by which BBB dysfunction may mediate TBI-induced AD pathology. Finally, we investigate the shared molecular pathways associated with BBB dysfunction in both TBI and AD conditions and discuss the latest findings on how targeting these pathways and employing regenerative approaches, such as stem cell therapy and pharmacological interventions, can enhance BBB function and mitigate neurodegeneration.

Kinetics of Circulating Progenitor Cells and Chemotactic Factors in Full-Term Neonates with Encephalopathy: Indications of Participation in the Endogenous Regenerative Process

Preclinical studies have shown that progenitor cells (PCs) are mobilized toward injured tissues to ameliorate damage and contribute to regeneration. The exogenous therapeutic administration of PCs in children affected by neonatal encephalopathy (NE) is a promising, yet underreported, topic. In this prospective study, we investigated whether endogenous circulating progenitor cells (CPCs) are involved in intrinsic regeneration mechanisms following neonatal brain injury. Thirteen full-term infants with moderate/severe NE, eleven with perinatal stress, and twelve controls were enrolled. Blood samples were collected on days 1, 3, 9, 18, and 45, as well as at 8 and 24 months of life, and were analyzed with a focus on Endothelial Progenitor Cells, Haematopoietic Stem Cells, and Very Small Embryonic-Like Stem Cells, in addition to chemotactic factors (erythropoietin, IGF-1, and SDF-1). Correlations between CPCs, chemotactic factors, and brain injury were assessed using serum levels of brain injury biomarkers (S100B and neuron-specific enolase), brain MRIs, and Bayley III developmental scores. Increased brain injury biomarkers were followed by the upregulation of SDF-1 receptor and erythropoietin and, finally, by elevated CPCs. These findings suggest a potential endogenous regenerative effort, primarily observed in the moderate encephalopathy group, but this is suppressed in cases of severe brain injury. Mimicking and enhancing endogenous regeneration pathways in cases of failure-regarding cell type and timeframe-could provide a novel therapeutic model.

Circulating CD34+ Cells: A New Biomarker of Residual Pulmonary Vascular Obstruction after Pulmonary Embolism

Pulmonary embolism (PE) is a life-threatening condition with long-term complications, including residual pulmonary vascular obstruction (RPVO). RPVO is associated with an increased risk of venous thromboembolism recurrence, chronic symptoms, and reduced quality of life. We hypothesize that an endothelial activation and vascular injury play a central role in the pathophysiology of RPVO. This prospective monocentric study investigates the potential of circulating biomarkers, including CD34⁺ cells, circulating endothelial cells (CECs), and platelet-derived growth factor BB (PDGF-BB), as indicators of vascular sequelae and predictors of RPVO. We included 56 patients with a first episode of PE. Biomarker levels were measured at PE diagnosis and six months later, coinciding with RPVO assessment using ventilation-perfusion lung scans. This defined groups of patients with (RPVO ≥ 10%) and without (RPVO < 10%) perfusion defects. Associations between biomarker levels, presence of perfusion defects, and clinical parameters were analyzed. At PE diagnosis, CEC and PDGF-BB levels were significantly elevated in patients compared to healthy controls, while CD34⁺ levels showed no difference. At the six-month follow-up, patients with perfusion defects exhibited significantly lower CD34⁺ cell levels compared to those without (median 1440 cells/mL vs. 2960 cells/mL). No significant differences in CEC or PDGF-BB levels were observed at follow-up. In conclusion, low CD34⁺ cell levels at RPVO assessment suggest a decreased regenerative potential contributing to thrombus persistence. CD34⁺ cells may serve as biomarkers for perfusion defects and warrant further study for their potential role in guiding clinical management of PE complications.

Pathogenic Mechanisms of Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD)-Associated Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the sixth most common cancer and the third leading cause of cancer deaths worldwide. The etiology of HCC has now dramatically changed from viral hepatitis to metabolic dysfunction-associated steatotic liver disease (MASLD). The main pathogenesis of MASLD-related HCC is the hepatic lipid accumulation of hepatocytes, which causes chronic inflammation and the subsequent progression of hepatic fibrosis. Chronic hepatic inflammation generates oxidative stress and DNA damage in hepatocytes, which contribute to genomic instability, resulting in the development of HCC. Several metabolic and molecular pathways are also linked to chronic inflammation and HCC in MASLD. In particular, the MAPK and PI3K-Akt-mTOR pathways are upregulated in MASLD, promoting the survival and proliferation of HCC cells. In addition, MASLD has been reported to enhance the development of HCC in patients with chronic viral hepatitis infection. Although there is no approved medication for MASLD besides resmetirom in the USA, there are some preventive strategies for the onset and progression of HCC. Sodium-glucose cotransporter-2 (SGLT2) inhibitor, a class of medications, has been reported to exert anti-tumor effects on HCC by regulating metabolic reprogramming. Moreover, CD34-positive cell transplantation improves hepatic fibrosis by promoting intrahepatic angiogenesis and supplying various growth factors. Furthermore, exercise improves MASLD through an increase in energy consumption as well as changes in chemokines and myokines. In this review, we summarize the recent progress made in the pathogenic mechanisms of MASLD-associated HCC. Furthermore, we introduced new therapeutic strategies for preventing the development of HCC based on the pathogenesis of MASLD.

Polyethylene Glycol Loxenatide Accelerates Diabetic Wound Healing by Downregulating Systemic Inflammation and Improving Endothelial Progenitor Cell Functions

Diabetes wound healing presents several significant challenges, which can complicate recovery and lead to severe consequences. Polyethylene glycol loxenatide (PEG-loxe), a long-acting glucagon-like peptide-1 receptor agonist (GLP-1RA), shows cardiovascular benefits, yet its role in diabetic wound healing remains unclear. Diabetic mice received PEG-loxe (0.03 mg/kg/week, i.p.) for three months. Glucose metabolism was evaluated using the insulin tolerance test (ITT) and oral glucose tolerance test (OGTT). Wound closure rates and angiogenesis-related proteins were analyzed. Serum proteomics was performed using the Olink assay to evaluate systemic inflammation. In vitro, human endothelial progenitor cells (EPCs) were exposed to high glucose and palmitic acid, with or without PEG-loxe treatment. EPC tube formation and migratory capacity were evaluated using the tube formation assay and migration assay, respectively. Levels of nitric oxide (NO) and phosphorylated endothelial nitric oxide synthase (p-eNOS) were quantified. Mitochondrial reactive oxygen species (ROS) production and mitochondrial membrane potential were assessed using MitoSOX and JC-1 staining. Cellular respiratory function was analyzed via the Seahorse XF assay. Autophagy was evaluated by examining the expression of autophagy-related proteins and the colocalization of mitochondria with lysosomes. PEG-loxe improved glucose tolerance, accelerated wound closure, and upregulated the hypoxia-inducible factor-1α/vascular endothelial growth factor/stromal cell-derived factor-1 axis (HIF-1α/VEGF/SDF-1) in diabetic mice. Serum proteomics revealed reduced pro-inflammatory markers and elevated anti-inflammatory IL-5. In vitro, PEG-loxe restored EPC function by enhancing NO production, reducing mitochondrial ROS, improving cellular respiratory function, and restoring autophagic flux. These findings suggest that PEG-loxe offers therapeutic benefits for diabetic wound healing by downregulating systemic inflammation, enhancing angiogenesis, and improving mitochondrial quality control in EPCs, highlighting GLP-1RAs as potential therapies for diabetic vascular complications.

Immune-privileged cord blood-derived endothelial colony-forming cells: advancing immunomodulation and vascular regeneration

Cord blood-derived endothelial colony-forming cells (CB-ECFCs) hold significant promise for regenerative medicine due to their unique vasculogenic and immunomodulatory properties. These cells exhibit a superior proliferative capacity, robust ability to form vascular networks, and lower immunogenicity compared to adult and embryonic stem cell-derived counterparts. The immune-privileged characteristics of CB-ECFCs, including reduced expression of pro-inflammatory mediators and tolerance-inducing molecules such as HLA-G, further enhance their therapeutic potential. Their low immunogenicity minimizes the risk of immune rejection, making them suitable for allogenic cell therapies. Their application extends to complex tissue engineering and organ revascularization, where their ability to integrate into three-dimensional scaffolds and support vascular tree formation represents a significant advancement. Moreover, CB-ECFCs' capability to adapt to inflammatory stimuli and retain immunological memory highlights their functional versatility in dynamic microenvironments. This review highlights the remarkable ontogeny of ECFCs while unveiling the unparalleled potential of CB-ECFCs in revolutionizing regenerative medicine. From pre-vascularizing engineered tissues and organoids to pioneering cell-based therapies for cardiovascular, dermatological, and degenerative diseases, CB-ECFCs stand at the forefront of cutting-edge biomedical advancements, offering unprecedented opportunities for therapeutic innovation. By leveraging their vasculogenic, immune-regulatory, and regenerative capacities, CB-ECFCs offer a robust alternative for addressing the challenges of vascular repair and organ engineering. Future research should focus on unraveling their transcriptomic and functional profiles to optimize clinical applications and advance the field of regenerative medicine.

Advancements in utilizing CD34+ stem cells for repairing diabetic vascular damage

Diabetes-related vascular damage is a frequent complication of diabetes that results in structural and functional impairment of blood vessels. This damage significantly heightens the risk of cardiovascular events. CD34+ stem cells have shown great potential in the treatment of diabetes-related vascular damage due to their differentiation and vascular repair capabilities. This article provides a review of the research hotspots on the role and mechanisms of CD34+ stem cells in the repair of diabetes-related vascular damage, including changes in cell quantity and function during diabetes, as well as the latest research on activating, protecting, or repairing these cells to prevent or treat vascular damage. The article also summarizes the impact of diabetes on the mobilization and function of CD34+ stem cells, emphasizing how diabetes negatively affects their ability to promote angiogenesis. These deficits can result in various complications, including issues with small blood vessels, coronary heart disease, foot problems, and retinal complications. On the clinical side, the article highlights the positive effects of CD34+ stem cell therapy in improving vascular function and tissue repair in diabetic patients, while also mentioning the inconsistencies in results between diabetes models and clinical studies, which necessitate further research to optimize treatment strategies. It emphasizes the importance of enhancing the mobilization, homing, and repair capabilities of CD34+ stem cells, as well as combining them with other treatment methods, to develop more effective strategies for treating diabetes-related vascular damage.

Platelet concentrates in diabetic foot ulcers: A comparative review of PRP, PRF, and CGF with case insights

Diabetic foot ulcers (DFUs) are severe complications of diabetes, often leading to chronic wounds, amputations, and increased mortality risk. Platelet concentrates (PCs)-natural biomaterials utilized in regenerative medicine-have garnered attention for their capacity to enhance tissue repair and wound healing. This study reviews the preparation methods, biological mechanisms, and clinical efficacy of three generations of PCs: platelet-rich plasma (PRP), platelet-rich fibrin (PRF), and concentrated growth factors (CGF). Comparative analysis reveals that PRP, the first generation, provides abundant growth factors but relies on anticoagulants, which may hinder fibrin formation and tissue adhesion. PRF, as the second generation, eliminates anticoagulants, forming a fibrin matrix that sustains growth factor release and enhances cell migration. CGF, the latest advancement, employs refined centrifugation to achieve higher growth factor concentrations and a denser fibrin matrix, accelerating tissue regeneration. Case series results demonstrated superior wound healing outcomes with CGF, including faster epithelialization and reduced healing time compared to PRP and PRF. These findings underscore CGF's potential as the most effective PC for managing DFUs, supporting its broader clinical adoption in advanced wound care.

Remote Continuous Microinjury-Triggered Cytokines Facilitate Severe Diabetic Foot Ulcer Healing via the Ras/Raf/MEK/ERK Pathway

PURPOSE

Microinjury can trigger in situ tissue repair. Bone transport consists of continuous microinjuries/microfracture and induces bone formation and angiogenesis. Tibial cortex transverse transport (TTT) was found to promote angiogenesis at the foot and the healing of diabetic foot ulcers (DFUs). However, the underlying mechanism remains largely unknown.

METHODS

We divided 72 Sprague-Dawley rats with DFUs into the control, sham, and TTT groups. Wound measurement and histology were performed to evaluate the wound healing processes. Enzyme-linked immunosorbent assay, flow cytometry, immunohistochemistry, and Western Blot were used to assess angiogenesis and the activity of endothelial progenitor cells (EPCs) and the Ras/Raf/MEK/ERK signaling pathway.

RESULTS

We found accelerated wound healing, improved epidermal continuity, and increased dermal thickness in the TTT group than the control and the sham groups. Higher levels of serum TGF-β1, PDGF-BB, and VEGF were detected in the TTT group. These changes were in parallel with the expression of TGF-β1, PDGF-BB, and VEGF in the foot wounds and the frequency of EPCs in both bone marrow and peripheral circulation, which implied that the secreted TGF-β1, PDGF-BB, and VEGF promote proliferation and migration of EPCs to the foot wounds. The expression of CD31+ cells, SMA-α+ cells, and the Ras/Raf/MEK/ERK pathway was higher in the TTT group than in the control and sham groups.

CONCLUSION

The findings showed that TTT enhanced the production of growth factors that in turn activated EPC proliferation and migration through the Ras/Raf/MEK/ERK pathway, ultimately contributing to angiogenesis and DFU healing. Based on these findings, we proposed a theory that remote continuous microinjuries can trigger the repair of target tissues (ie, microinjury-induced remote repair, MIRR). Future studies are needed to validate this theory.

Endothelial Colony-Forming Cells (ECFCs) in cerebrovascular aging: Focus on the pathogenesis of Vascular Cognitive Impairment and Dementia (VCID), and treatment prospects

Endothelial colony-forming cells (ECFCs), a unique endothelial progenitor subset, are essential for vascular integrity and repair, providing significant regenerative potential. Recent studies highlight their role in cerebrovascular aging, particularly in the pathogenesis of vascular cognitive impairment and dementia (VCID). Aging disrupts ECFC functionality through mechanisms such as oxidative stress, chronic inflammation, and cellular senescence, leading to compromised vascular repair and reduced neurovascular resilience. ECFCs influence key cerebrovascular processes, including neurovascular coupling (NVC), blood-brain barrier (BBB) integrity, and vascular regeneration, which are critical for cognitive health. Age-related decline in ECFC quantity and functionality contributes to vascular rarefaction, diminished cerebral blood flow (CBF), and BBB permeability-processes that collectively exacerbate cognitive decline. This review delves into the multifaceted role of ECFCs in cerebrovascular aging and underscores their potential as therapeutic targets in addressing age-related vascular dysfunctions, presenting new directions for mitigating the effects of aging on brain health.

Comparative Evaluation of Endothelial Colony-Forming Cells from Cord and Adult Blood vs. Human Embryonic Stem Cell-Derived Endothelial Cells: Insights into Therapeutic Angiogenesis Potential

The discovery of endothelial progenitor cells has revolutionized our understanding of postnatal blood vessel formation, with endothelial colony-forming cells (ECFCs) emerging as key players in vasculogenesis. Among various ECFC sources, cord blood-derived ECFCs (CB-ECFCs) are of particular interest due to their superior proliferative and clonogenic potential and their ability to promote vascular network formation. Human embryonic stem cell-derived endothelial cells (hESC-ECs) have also shown potential in regenerative medicine, though their vasculogenic efficacy remains unclear compared to CB- and adult blood-derived ECFCs (AB-ECFCs). This study aimed to directly compare the angiogenic and vasculogenic capabilities of CB-ECFCs, AB-ECFCs, and hESC-ECs in vitro and in vivo. Our results demonstrated that CB-ECFCs had a significantly higher proliferation rate than both AB-ECFCs and hESC-ECs (p < 0.01). In tube formation assays, CB-ECFCs exhibited superior ability to form capillary-like structures compared to hESC-ECs (p < 0.0001) and AB-ECFCs (p < 0.01). In vivo, CB-ECFCs significantly improved blood flow recovery in ischemic tissue (p < 0.01), outperforming both AB-ECFCs and hESC-ECs, with no significant recovery observed in the latter two groups. These findings suggest that CB-ECFCs represent a more effective cell source for therapeutic angiogenesis, while further optimization is needed to enhance the efficacy of hESC-ECs for clinical applications. Future research should explore the molecular mechanisms underlying the superior regenerative potential of CB-ECFCs and focus on improving the stability and functionality of stem cell-derived ECs for therapeutic use.

Extracellular Vesicles-in-Hydrogel (EViH) targeting pathophysiology for tissue repair

Regenerative medicine endeavors to restore damaged tissues and organs utilizing biological approaches. Utilizing biomaterials to target and regulate the pathophysiological processes of injured tissues stands as a crucial method in propelling this field forward. The Extracellular Vesicles-in-Hydrogel (EViH) system amalgamates the advantages of extracellular vesicles (EVs) and hydrogels, rendering it a prominent biomaterial in regenerative medicine with substantial potential for clinical translation. This review elucidates the development and benefits of the EViH system in tissue regeneration, emphasizing the interaction and impact of EVs and hydrogels. Furthermore, it succinctly outlines the pathophysiological characteristics of various types of tissue injuries such as wounds, bone and cartilage injuries, cardiovascular diseases, nerve injuries, as well as liver and kidney injuries, underscoring how EViH systems target these processes to address related tissue damage. Lastly, it explores the challenges and prospects in further advancing EViH-based tissue regeneration, aiming to impart a comprehensive understanding of EViH. The objective is to furnish a thorough overview of EViH in enhancing regenerative medicine applications and to inspire researchers to devise innovative tissue engineering materials for regenerative medicine.

Recent advances in surface functionalization of cardiovascular stents

Cardiovascular diseases (CVD) are the leading global threat to human health. The clinical application of vascular stents improved the survival rates and quality of life for patients with cardiovascular diseases. However, despite the benefits stents bring to patients, there are still notable complications such as thrombosis and in-stent restenosis (ISR). Surface modification techniques represent an effective strategy to enhance the clinical efficacy of vascular stents and reduce complications. This paper reviews the development strategies of vascular stents based on surface functional coating technologies aimed at addressing the limitations in clinical application, including the inhibition of intimal hyperplasia, promotion of re-endothelialization. These strategies have improved endothelial repair and inhibited vascular remodeling, thereby promoting vascular healing post-stent implantation. However, the pathological microenvironment of target vessels and the lipid plaques are key pathological factors in the development of atherosclerosis (AS) and impaired vascular repair after percutaneous coronary intervention (PCI). Therefore, restoring normal physiological environment and removing the plaques are also treatment focuses after PCI for promoting vascular repair. Unfortunately, research in this area is limited. This paper reviews the advancements in vascular stents based on surface engineering technologies over the past decade, providing guidance for the development of stents.

Differentiation of lung tissue-resident c-Kit+ cells into microvascular endothelial cells alleviates pulmonary vascular remodeling

Pulmonary vascular remodeling (PVR), encompassing microvascular loss and muscularization, contributes to multiple respiratory diseases. c-Kit+ cells exhibit differentiation potential into both endothelial cells (ECs) and smooth muscle cells. The potential role of lung c-Kit+ cell differentiation in PVR, however, remains unclear. Lung c-Kit+ cells increase in pulmonary hypertension patients and in the SU5416/hypoxia (SuHx)-induced PVR mouse model. Employing genetic lineage tracing and single-cell RNA sequencing (scRNA-seq), we elucidate that lung-resident c-Kit+ cells display an aerocyte and venular endothelial differentiation in the SuHx model. Ablation of tissue-resident c-Kit+ cells exacerbates PVR. We identify an Nr2f2-expressing c-Kit+ cell subgroup, which exhibitsvenous EC differentiation and increases during PVR. Notably, the elevation of Nr2f2 in c-Kit+ cells via AAV enhances differentiation and mitigates PVR. These findings underscore the protective role of lung tissue-resident c-Kit+ cells in PVR, achieved by differentiating into mature ECs. Targeting NR2F2 expression in c-Kit+ cells emerges as a promising strategy for reversing PVR.

Adjuvant Treatment with Empagliflozin or Semaglutide Increases Endothelial Progenitor Cells in Subjects with Well-Controlled Type 1 Diabetes Mellitus

Circulating endothelial cells (CECs) and endothelial progenitor cells (EPCs) are promising markers of vascular damage and endothelial regeneration potential. We focused on the detection of CECs and EPCs using flow cytometry with regard to analytical challenges and its suitability for routine testing. As part of a clinical validation, CECs and EPCs were measured in blood samples from 83 subjects with type 1 diabetes (T1DM), evaluating an adjuvant intervention with two different antidiabetic drugs, empagliflozin (N = 28) and semaglutide (N = 29). Both groups receiving adjuvant therapy were compared with the insulin-only group (N = 26) at two time points: before the start of therapy and after 12 weeks of adjuvant therapy. All three groups were comparable regarding demographic characteristics and concomitant risk factors. Absolute and relative endothelial cell count at baseline were low and comparable to those of healthy individuals. In the group receiving empagliflozin or semaglutide, a significant increase in EPC was observed after 12 weeks of treatment. We demonstrated that EPCs have the potential to serve as markers for monitoring the efficacy of adjuvant therapy in T1DM patients. However, before their implementation in clinical practice, the flow cytometry protocol for CEC and EPC identification and quantification must be standardized.

Cellular therapy for the peripheral arterial disease treatment: Protocol for a systematic review and meta-analysis

Cellular therapy is a promising treatment option for Peripheral Arterial Disease (PAD). Different cell types can be used to regenerate and repair tissues affected by PAD. Many studies have proposed the use of stem cells, such as mesenchymal stem cells, or even mononuclear cells isolated from peripheral blood or bone marrow, to treat PAD. This paper reports a protocol of systematic review and meta-analysis that aims to identify the effects of stem cell treatment in patients with peripheral arterial disease. The search will be conducted in the following database: PubMed/MEDLINE, Clinicaltrial.gov, Scopus, Embase, Epistemonikos, Web of Science and Cochrane Library. Studies will be selected independently by two reviewers and will include all published randomized and non-randomized clinical trials. The data extraction will include studies population characteristics, type of treatment and main outcomes. We will assess the methodological quality of the studies using the Cochrane Risk of Bias 2.0 and Risk of Bias in Non-randomized Studies of Interventions. The certainty of the evidence will be rate using the Grading of Recommendations, Assessment, Development, and Evaluations. The findings will be presented in narrative summary tables and in a meta-analysis.

Impact of Periodontitis and Oral Dysbiosis Metabolites in the Modulation of Accelerating Ageing and Human Senescence

Periodontitis, a chronic multifactorial inflammatory condition of the periodontium, is originated by a dysbiotic oral microbiota and is negatively correlated with several systemic diseases. The low-chronic burden of gingival inflammation not only exacerbates periodontitis but also predisposes individuals to a spectrum of age-related conditions, including cardiovascular diseases, neurodegenerative disorders, and metabolic dysfunction, especially related to ageing. In this regard, over the local periodontal treatment, lifestyle modifications and adjunctive therapies may offer synergistic benefits in ameliorating both oral and systemic health in ageing populations. Elucidating the intricate connections between periodontitis and senescence is important for understanding oral health's systemic implications for ageing and age-related diseases. Effective management strategies targeting the oral microbiota and senescent pathways may offer novel avenues for promoting healthy ageing and preventing age-related morbidities. This review will analyze the current literature about the intricate interplay between periodontitis, oral dysbiosis, and the processes of senescence, shedding light on their collective impact on the modulation and accelerated ageing and age-related diseases. Lastly, therapeutic strategies targeting periodontitis and oral dysbiosis to mitigate senescence and its associated morbidities will be discussed.

In Vitro models of leukemia development: the role of very small leukemic stem-like cells in the cellular transformation cascade

Recent experimental findings indicate that cancer stem cells originate from transformed very small embryonic-like stem cells. This finding represents an essential advancement in uncovering the processes that drive the onset and progression of cancer. In continuously growing cell lines, for the first time, our team's follow-up research on leukemia, lung cancer, and healthy embryonic kidney cells revealed stages that resembles very small precursor stem cells. This review explores the origin of leukemic stem-like cells from very small leukemic stem-like cells establish from transformed very small embryonic-like stem cells. We explore theoretical model of acute myeloid leukemia initiation and progresses through various stages, as well basing the HL60 cell line, present its hierarchical stage development in vitro, highlighting the role of these very small precursor primitive stages. We also discuss the potential implications of further research into these unique cellular stages for advancing leukemia and cancer treatment and prevention.

Isolation, Purification, Generation, and Culture of Osteocytes

Osteocytes reside within the bone matrix and produce both paracrine and endocrine factors that influence the skeleton and other tissues. Despite their abundance and physiological importance, osteocytes have been challenging to study in vitro because they are difficult to extract and purify and do not retain their phenotype in standard culture conditions. New techniques for this purpose are emerging. This chapter will describe two methods and adaptations we use to study osteocytes: (1) isolating and purifying primary osteocytes from murine bone, with and without hematopoietic lineage depletion and (2) differentiating cultured osteoblasts or osteoblast-lineage cell lines (including cell lines termed "osteocytic") until they reach a stage of osteocytic gene expression. We will also discuss the limitations of these methods and possible directions for future improvements.

Endothelial and circulating progenitor cells as prognostic biomarkers of stroke: A systematic review and meta-analysis

PURPOSE

Endothelial progenitor cells (EPCs) are biomarkers of neurovascular repair in cerebral vascular disease (CVD). Low quantification of EPCs and/or their dysfunction has been associated with stroke severity and post-stroke functionality. This systematic review (SR) and meta-analysis aimed to analyze whether EPC quantification contributes to stroke severity and functional prognosis.

METHODS

Articles were selected from the PubMed, ScienceDirect, and Ovid MEDLINE databases, according to the guidelines of the PRISMA 2020 [1] statement. Detailed observational studies of samples from subjects with a clinical diagnosis of CVD (ischemic stroke-IS, hemorrhagic stroke-HS, or transient ischemic attack-TIA) aged >45 years during 2003-2023 were included. Evaluation of study quality was based on the Critical Appraisal Skills Programme checklist(Santamaría, 2017 [2]).

RESULTS

We included 22 articles in our SR. Patients with IS and good functional outcomes had higher EPC levels during the first week of admission than those with worse functional outcomes. Higher EPC levels were associated with reduced infarct growth, improved NIHSS scores at 48 h (OR 0.8; 95 % CI: 0.72-0.90; p < 0.0002) 7 (r = -0.607; p < 0.0001), and 90 days (r = -0.570; p < 0.0001), with a negative correlation between EPC levels and NIHSS score (overall pooled r = -0,32, 95 % CI: -0.39-0.24), and good functional outcomes with better mRS scores at 24 h, 3, 6, and 12 months (overall pooled SMD 4.51, CI 95 %: 0.70-0.83). Lower EPC quantification and worse functional outcomes during admission were predictors of IS recurrence. Higher EPC levels were associated with better functional outcomes and lower bleeding volumes in patients with HS and were protective markers for the progression high-risk TIA.

CONCLUSION

EPCs seems to be predictive biomarkers of better clinical outcomes in patients with CVD, exhibiting lower severity (NIHSS) and better functional prognosis (mRS).

Stent strategies: Endothelial progenitor cell coated stents vs sirolimus eluting stents in a pairwise meta-analysis

BACKGROUND

Endothelial progenitor cells (EPCs) capturing stents were developed to enhance endothelial repair and reduce the risk of stent thrombosis, addressing limitations of Sirolimus-Eluting Stents (SES). This study aims to compare the safety and efficacy of EPC stents versus SES in patients undergoing percutaneous coronary intervention (PCI).

METHODS

We performed a meta-analysis following PRISMA guidelines in patients undergoing PCI treated with Sirolimus eluting stent (SES) vs the use of EPC stents and recognized 8 clinical trials with patients undergoing PCI and reporting outcomes such as Target Lesion Failure (TLF), stent thrombosis, and revascularisation. Relative risks were calculated using a random effects model and heterogeneity was assessed with I^2 statistics.

RESULTS

The EPC group showed higher incidence of TLF (RR ​= ​1.28), MI(RR ​= ​1.10), and cardiac death (RR ​= ​1.19) compared to SES, though these differences were not statistically significant. Revascularisation rates were significantly higher in EPC group with TVR (RR ​= ​1.60) and TLR(RR ​= ​2.20) while stent thrombosis was lower (RR ​= ​0.93).

CONCLUSION

The results of this EPC study reveals that while EPC stents show promise in revascularisation and lowering stent thrombosis, they are also associated with higher incidence of adverse events. The utility of EPC, especially vast reendothelialization, may have niche applications but their full potential can be realized with more rigorous trials as a clear advantage over SES remains lacking.

Purified CD34+ Cells Transplantation in Patients with Angiitis-Induced Chronic Limb-Threatening Ischemia: A Single-Center Retrospective Study over a 10-Year Period

BACKGROUND

Angiitis-induced chronic limb-threatening ischemia (AICLTI) is defined as chronic limb-threatening ischemia caused by thromboangiitis obliterans or other arteritis-related autoimmunological diseases. In the current study, we aimed to report the 10-year outcomes of AICLTI patients who underwent purified cluster of differentiation 34 positive (CD34+) cells (PCCs) transplantation.

METHODS

AICLTI patients who underwent PCCs transplantation at our center from May 2009 to September 2011 were retrospectively enrolled. The main outcome was major amputation-free survival (MAFS); other outcomes included Rutherford classification, intolerable pain-free walking time, Wong-Baker Faces Pain Rating Scale, recurrence, new lesions, quality of life and patients' posttransplantation work conditions.

RESULTS

Twenty-four patients were enrolled with a mean age of 41.5 ± 7.8 years. Three underwent major amputation during the follow-up, and the 10-year MAFS was 87.5%. Eight were observed to have recurrence, and 2 had new lesions; the 10-year recurrence-free rate was 66.1%. All patients were unable to work at admission, 17 (70.8%) patients were reemployed after transplantation.

CONCLUSIONS

The current study further demonstrated satisfactory long-term efficacy of PCCs transplantation, with a 10-year MAFS of 87.5%. However, the 10-year recurrence-free rate of 66.1% suggested that strict and regular long-term follow-up is necessary.

Prognostic Factors After Bone Marrow-Derived Mononuclear Cell Implantation in No-Option Chronic Limb-Threatening Ischemia Patients with Atherosclerotic Lower Extremity Artery Disease

Previous studies have reported the efficacy and safety of therapeutic angiogenesis through bone marrow-derived mononuclear cell (BM-MNC) implantation in patients with no-option chronic limb-threatening ischemia (CLTI) from atherosclerotic lower extremity artery disease (LEAD). However, uncertain clinical prognostic factors impact treatment outcomes. This study aimed to elucidate the long-term outcomes of patients with atherosclerotic LEAD-derived no-option CLTI after BM-MNC implantation and to identify prognostic factors.In this retrospective, single-center, observational study, the primary endpoints included the long-term prognosis of BM-MNC implantation and factors influencing 1-year outcomes. A total of 92 limbs in 84 patients were analyzed in the final cohort (mean age: 67 years; male, 65%). The 5- and 10-year overall survival rates were 50.0% and 31.0%, respectively, while the 5- and 10-year amputation-free survival rates were 37.6% and 23.3%, respectively. Multivariate logistic analysis linked all-cause mortality to age ≥ 70 years, hemodialysis, smoking, and a controlling nutrition status score ≥ 5. Major amputation or mortality was associated with male sex, hemodialysis, and C-reactive protein levels ≥ 3.0 mg/dL. No adverse events were associated with therapeutic angiogenesis.These findings endorse the feasibility and safety of BM-MNC implantation for patients with no-option CLTI due to atherosclerotic LEAD. Moreover, the study highlights the significance of several prognostic factors, including advanced age, hemodialysis, smoking, and inflammatory markers, in influencing the long-term outcomes of this treatment.

Endothelial heterogeneity in bone marrow: insights across development, adult life and leukemia

The central role of the endothelial microenvironment in orchestrating bone marrow (BM) homeostasis and hematopoietic support has been confirmed at various developmental stages and in adult life. The BM vasculature is crucial in mediating communication between BM parenchyma and circulating blood, displaying remarkable heterogeneity in structure and function. While vascular cell diversity in other tissues has long been recognized, the molecular basis of this phenomenon in BM is just now emerging. Over the past decade, single-cell approaches and microscopic observations have expanded our understanding of BM vasculature. While solely characterized for their paracrine properties in the past, recent advances have revolutionized our perception of endothelial function, revealing distinct anatomical locations associated with diverse endothelial cell states. The identification of phenotypic differences between normal and pathological conditions has therefore deepened our understanding of vascular dynamics and their impact on hematopoiesis in health and disease. In this review, we highlight key milestones and recent advances in understanding vascular heterogeneity within BM microenvironment during development, adulthood and aging. We also explore how leukemia affects this heterogeneity and how we can take this knowledge forward to improve clinical practices. By synthesizing existing literature, we aim to address unresolved questions and outline future research directions.

The role of vascularity and the fibrovascular interface in interstitial lung diseases

Interstitial lung disease (ILD) is a clinical term that refers to a diverse group of non-neoplastic lung diseases. This group includes idiopathic and secondary pulmonary entities that are often associated with progressive pulmonary fibrosis. Currently, therapeutic approaches based on specific structural targeting of pulmonary fibrosis are limited to nintedanib and pirfenidone, which can only slow down disease progression leading to a lower mortality rate. Lung transplantation is currently the only available curative treatment, but it is associated with high perioperative mortality. The pulmonary vasculature plays a central role in physiological lung function, and vascular remodelling is considered a hallmark of the initiation and progression of pulmonary fibrosis. Different patterns of pulmonary fibrosis commonly exhibit detectable pathological features such as morphomolecular changes, including intussusceptive and sprouting angiogenesis, vascular morphometry, broncho-systemic anastomoses, and aberrant angiogenesis-related gene expression patterns. Dynamic cellular interactions within the fibrovascular interface, such as endothelial activation and endothelial-mesenchymal transition, are also observed. This review aims to summarise the current clinical, radiological and pathological diagnostic algorithm for different ILDs, including usual interstitial pneumonia/idiopathic pulmonary fibrosis, non-specific interstitial pneumonia, alveolar fibroelastosis/pleuroparenchymal fibroelastosis, hypersensitivity pneumonitis, systemic sclerosis-related ILD and coronavirus disease 2019 injury. It emphasises an interdisciplinary clinicopathological perspective. Additionally, the review covers current therapeutic strategies and knowledge about associated vascular abnormalities.

Ticagrelor Induces Angiogenesis in Progenitor and Mature Endothelial Cells In Vitro: Investigation of the Possible Role of Adenosine

Ticagrelor, a reversible platelet P2Y12 receptor antagonist, exerts various pleiotropic actions, some of which are at least partially mediated through adenosine. We studied the ticagrelor and adenosine effect on the angiogenic properties of progenitor CD34+-derived endothelial colony-forming cells (ECFCs). Angiogenesis studies were performed in vitro using capillary-like tube formation and spheroid-based angiogenesis assays. The effects of adenosine receptor antagonists, including DPCPX (A1 antagonist), SCH58621 (A2A antagonist), MRS1706 (A2B inverse agonist and antagonist), MRS1220 (A3 antagonist) and adenosine deaminase (ADA), were also investigated. Ticagrelor, adenosine, and their combination increased capillary-like tube formation and spheroid sprout formation by ECFCs in a dose-dependent manner. This effect was significantly reduced by SCH58621, MRS1706, and their combination, as well as by ADA. By contrast, DPCPX and MRS1220 did not exhibit any inhibitory effects. Similar results were obtained when mature human umbilical vein endothelial cells (HUVECs) were studied. These results show that ticagrelor stimulates angiogenesis by progenitor and mature endothelial cells in an adenosine-dependent pathway in which the adenosine receptors A2A and A2B play major roles. The significance of these results at the clinical level in patients with atherothrombotic events and treated with ticagrelor needs to be investigated.

Astilbin exerts anti-hypersensitivity by regulating metabolic demand and neuronal activity in rodent model of neuropathic pain

OBJECTIVE

Astilbe chinensis, is a traditional Chinese medicine commonly employed for pain management. However, its primary active ingredient remains a subject of debate.

METHODS

Spinal nerve ligation (SNL) and formalin-induced pain models were employed. Network pharmacology and bioinformatics were utilized to identify targets. Verification was performed through spinal cord double immunofluorescence staining, quantitative PCR and whole-cell recording techniques.

RESULTS

In experiments conducted on neuropathic rats, both systemic and intrathecal administration of astilbin, an essential constituent, exhibited a noteworthy and dose-dependently decrease in chronic and acute pain behaviours. The ED50 value, which represents the dose at which 50% effectiveness is achieved, was measure at 7.59 μg, while the Emax value, indicating the maximum attainable effect, was found to be 60% of the maximal possible effect (% MPE). Forty-two shared targets were identified, enriching the metabolic and synaptic pathways in the network pharmacology analysis, as confirmed by transcriptomic analysis. Weighted gene co-expression network analysis (WGCNA) revealed a strong correlation between the anti-nociceptive effects of astilbin and neuronal metabolic processes. Spinal functional ultrasound (FUS) analysis indicated increased spinal blood flow intensity and changes in metabolism-related enzyme activity, including stearoyl-CoA desaturase (Scd), 17beta-hydroxysteroid dehydrogenase (Hsd17b7) and sterol 14alpha-demethylase (Cyp51) in neuropathic rats, pretreatment with astilbin decreased formalin-induced blood flow in acute pain. Bath application of astilbin dose-dependently inhibited neuronal activity by reducing the frequency and amplitude of miniature excitatory postsynaptic currents (mEPSCs) without affecting miniature inhibitory postsynaptic currents (mIPSCs).

CONCLUSIONS

In summary, this study provides evidence that astilbin alleviates pain by modulating neuronal metabolic processes and synaptic homeostasis.

DLK1 promoted ischemic angiogenesis through notch1 signaling in endothelial progenitor cells

Delta like non-canonical Notch ligand 1 (DLK1), as a member of epidermal growth factor-like family, plays a critical role in somatic growth, tissue development and possibly tissue renewal. Though previous studies had indicated that DLK1 contributed to adipogenesis and myogenesis, it's still controversial whether DLK1 affects angiogenesis and how it interacts with Notch signaling with numerous conflicting reports from different models. Based on our preliminary finding that DLK1 expression was up-regulated in mice ischemic gastrocnemius and in the border zone of infarcted myocardium, we administered either recombinant DLK1 (rDLK1) or PBS in C57BL/6 mice after establishment of hindlimb ischemia (HLI) and myocardial infarction (MI), respectively. Exogenous rDLK1 administration significantly improved both blood perfusion of mice ischemic hindlimbs and muscle motor function on the 3rd, 7th day after HLI, by promoting neovascularization. Similar effect on neovascularization was verified in mice on the 28th day after MI as well as improvement of cardiac failure. Correspondingly, the number of CD34+KDR+ cells, indicated as endothelial progenitor cells (EPCs), was significantly in mice ischemic gastrocnemius by rDLK1 administration, which was abrogated by DAPT as the specific inhibitor of Notch intracellular domain (NICD). Furthermore, bone marrow mononuclear cells were obtained from C57BL/6 mice and differentiated to EPCs ex vivo. Incubation with rDLK1 triggered Notch1 mRNA and NICD protein expressions in EPCs as exposed to hypoxia and serum deprivation, promoting EPCs proliferation, migration, anti-apoptosis and tube formation. Otherwise, rDLK1 incubation significantly decreased intracellular and mitochondrial reactive oxygen species, increased ATP content and mitochondrial membrane potential, downregulated short isoform of OPA-1 expression whereas upregulated mitofusin (-1, -2) expression in EPCs by Notch1 signaling, which were all abrogated by DAPT. In summary, the present study unveils the pro-angiogenesis and its mechanism of rDLK1 through activation of Notch1 signaling in endothelial progenitor cells.

Targeting pericyte retention in Diabetic Retinopathy: a review

Diabetic retinopathy is a common yet severe complication of diabetes mellitus and is the leading cause of blindness in middle-aged adults. After years of poorly managed hyperglycemia, complications begin as non-proliferative diabetic retinopathy but can then progress into the proliferative stage marked by neovascularization of the retina. Multiple pathologic mechanisms caused by chronic hyperglycemia damage the retinal vasculature leading to pericyte drop out and the progression of the disease. This review outlines the major pathways of pathogenesis in diabetic retinopathy, highlighting the protective role pericytes play in preserving the blood-retinal barrier. Given the loss of this cell line is a defining feature of the disease, ways in which to prevent pericyte dropout within retinal vasculature is discussed, targeting various pathogenesis pathways of diabetic retinopathy.

Hepatic arterial infusion of autologous CD34+ cells for hepatitis C virus-related decompensated cirrhosis: A multicenter, open-label, exploratory randomized controlled trial

INTRODUCTION

In this multicenter clinical study, we aimed to investigate the efficacy and safety of the transhepatic arterial administration of granulocyte-colony stimulating factor (G-CSF)-mobilized autologous peripheral blood (PB)-CD34+ cells compared with standard therapy in patients with decompensated cirrhosis type C.

METHODS

Patients were randomly assigned (2:1) to the CD34+ cell transplant (CD34+ cell) or standard-of-care (SOC) group and followed up for 52 weeks. The primary endpoints were the non-progression rate of Child-Pugh (CP) scores at 24 weeks post-enrollment and the safety of the protocol treatment.

RESULTS

Fourteen patients (CD34+ cell group: 10; SOC group: 4) were enrolled. CP scores at 24 weeks had a non-progression rate of 90% in the CD34+ cell group and 100% in the SOC group, with no significant difference between groups. Importantly, 4 out of 10 patients in the CD34+ cell group exhibited an improvement from decompensated to compensated cirrhosis, whereas all patients in the SOC group remained in decompensated cirrhosis. With regard to secondary endpoints, a trend toward increased serum albumin levels in the CD34+ cell group was noted. Serious adverse events (SAEs) occurred in three patients in the CD34+ cell group and in one patient in the SOC group. No causal relationship was observed between all SAEs and G-CSF, leukapheresis, or cell transplantation in the CD34+ cell group. No patients died and no hepatocellular carcinoma occurred within the study period.

CONCLUSIONS

PB-CD34+ cell infusion therapy may have the potential to circumvent the decompensated stage of cirrhosis, thus avoiding the need for liver transplantation.

CXCL13 promote angiogenesis by recruiting M2 macrophages and endothelial progenitor cells in beige adipose grafts

Fat grafting is an emerging clinical technique to address soft tissue deficiencies. This study investigates whether the secretory function of beige adipose tissue(BeigeAT) grafts is involved in promoting soft tissue regeneration in fat grafting. In this study, mice were randomly divided into white adipose tissue (WAT) and BeigeAT groups. Each type of adipose tissue (0.3 mL) was transplanted into the respective groups, and samples were harvested at 2, 4, and 12 week. Subsequently, mice were further divided into three groups, BeigeAT group, BeigeAT with CXCL13 treatment group, and BeigeAT with TAK-779 treatment group, to investigate the role of CXCL13 in BeigeAT transplants. Graft retention rate, vascularization, and fibrosis levels were compared among the groups. Compared to WAT transplants, BeigeAT transplants exhibited moderate inflammation, enhanced revascularization, reduced fibrosis, and increased infiltration of M2 macrophages and endothelial progenitor cells in the early stages following fat grafting. CXCL13 expression was significantly higher in BeigeAT transplants at 2, 4, and 12 week post-grafting. Additionally, modulation of CXCL13 expression affected the infiltration of M2 macrophages and endothelial progenitor cells. However, BeigeAT transplants exhibited superior retention rates compared to BeigeAT CXCL13 groups and BeigeAT TAK-779 groups after 12 weeks of fat grafting. BeigeAT transplants achieve improved retention rates through CXCL13-induced infiltration of M2 macrophages and endothelial progenitor cells.

Senolysis potentiates endothelial progenitor cell adhesion to and integration into the brain vasculature

BACKGROUND

One of the most severe consequences of ageing is cognitive decline, which is associated with dysfunction of the brain microvasculature. Thus, repairing the brain vasculature could result in healthier brain function.

METHODS

To better understand the potential beneficial effect of endothelial progenitor cells (EPCs) in vascular repair, we studied the adhesion and integration of EPCs using the early embryonic mouse aorta-gonad-mesonephros - MAgEC 10.5 endothelial cell line. The EPC interaction with brain microvasculature was monitored ex vivo and in vivo using epifluorescence, laser confocal and two-photon microscopy in healthy young and old animals. The effects of senolysis, EPC activation and ischaemia (two-vessel occlusion model) were analysed in BALB/c and FVB/Ant: TgCAG-yfp_sb #27 mice.

RESULTS

MAgEC 10.5 cells rapidly adhered to brain microvasculature and some differentiated into mature endothelial cells (ECs). MAgEC 10.5-derived endothelial cells integrated into microvessels, established tight junctions and co-formed vessel lumens with pre-existing ECs within five days. Adhesion and integration were much weaker in aged mice, but were increased by depleting senescent cells using abt-263 or dasatinib plus quercetin. Furthermore, MAgEC 10.5 cell adhesion to and integration into brain vessels were increased by ischaemia and by pre-activating EPCs with TNFα.

CONCLUSIONS

Combining progenitor cell therapy with senolytic therapy and the prior activation of EPCs are promising for improving EPC adhesion to and integration into the cerebral vasculature and could help rejuvenate the ageing brain.

Emerging insights into epigenetics and hematopoietic stem cell trafficking in age-related hematological malignancies

BACKGROUND

Hematopoiesis within the bone marrow (BM) is a complex and tightly regulated process predominantly influenced by immune factors. Aging, diabetes, and obesity are significant contributors to BM niche damage, which can alter hematopoiesis and lead to the development of clonal hematopoiesis of intermediate potential (CHIP). Genetic/epigenetic alterations during aging could influence BM niche reorganization for hematopoiesis or clonal hematopoiesis. CHIP is driven by mutations in genes such as Tet2, Dnmt3a, Asxl1, and Jak2, which are associated with age-related hematological malignancies.

OBJECTIVE

This literature review aims to provide an updated exploration of the functional aspects of BM niche cells within the hematopoietic microenvironment in the context of age-related hematological malignancies. The review specifically focuses on how immunological stressors modulate different signaling pathways that impact hematopoiesis.

METHODS

An extensive review of recent studies was conducted, examining the roles of various BM niche cells in hematopoietic stem cell (HSC) trafficking and the development of age-related hematological malignancies. Emphasis was placed on understanding the influence of immunological stressors on these processes.

RESULTS

Recent findings reveal a significant microheterogeneity and temporal stochasticity of niche cells across the BM during hematopoiesis. These studies demonstrate that niche cells, including mesenchymal stem cells, osteoblasts, and endothelial cells, exhibit dynamic interactions with HSCs, significantly influenced by the BM microenvironment as the age increases. Immunosurveillance plays a crucial role in maintaining hematopoietic homeostasis, with alterations in immune signaling pathways contributing to the onset of hematological malignancies. Novel insights into the interaction between niche cells and HSCs under stress/aging conditions highlight the importance of niche plasticity and adaptability.

CONCLUSION

The involvement of age-induced genetic/epigenetic alterations in BM niche cells and immunological stressors in hematopoiesis is crucial for understanding the development of age-related hematological malignancies. This comprehensive review provides new insights into the complex interplay between niche cells and HSCs, emphasizing the potential for novel therapeutic approaches that target niche cell functionality and resilience to improve hematopoietic outcomes in the context of aging and metabolic disorders.

NOVELTY STATEMENT

This review introduces novel concepts regarding the plasticity and adaptability of BM niche cells in response to immunological stressors and epigenetics. It proposes that targeted therapeutic strategies aimed at enhancing niche cell resilience could mitigate the adverse effects of aging, diabetes, and obesity on hematopoiesis and clonal hematopoiesis. Additionally, the review suggests that understanding the precise temporal and spatial dynamics of niche-HSC interactions and epigenetics influence may lead to innovative treatments for age-related hematological malignancies.

Intravenous Regeneration-associated Cell Transplantation Enhances Tissue Recovery in Mice with Acute Ischemic Stroke

Previously, we reported that transplantation of regeneration-associated cells (RACs) via the ipsilateral external carotid artery reduced stroke volume in mice with permanent occlusion of the middle cerebral artery (MCA). However, intracarotid arterial transplantation is invasive and requires skill, and severe complications may occur, such as thromboembolism, infection, and decreased cerebral blood flow. This study aimed to investigate the efficacy of intravenous injection of RACs in reducing stroke volume and increasing anti-inflammatory and angiogenic factors in mice with focal cerebral ischemia. Mice with occluded MCAs received intravenous injections of phosphate-buffered saline (PBS) (control), low-dose RACs, or high-dose RACs. The proximal part of the left MCA was occluded to induce permanent focal ischemia. After 3 days, we administered PBS or low-dose (1 × 104 /50 µL) or high-dose RACs (1 × 105 /50 µL) through the tail vein and assessed the infarct volume on day 7. High-dose RACs significantly decreased infarct volume compared to PBS, whereas low-dose RACs showed no effect. The number of interleukin-10 (IL-10)-positive and vascular endothelial growth factor (VEGF)-positive cells in the peri-infarct area on day 7 was significantly higher in mice treated with low-dose and high-dose RACs than in the PBS control group. Intravenous injection of RACs can reduce ischemic stroke volume; however, a higher dose of RACs is required than the dose used in intraarterial transplantation. By assessing IL-10 and VEGF expression, the study sheds light on the underlying mechanisms of RAC therapy, revealing its potential anti-inflammatory and angiogenic properties in the treatment of cerebral ischemia.

Sevoflurane Postconditioning Protects From an Early Neurological Deficit After Subarachnoid Hemorrhage: Results of a Randomized Laboratory Study in Rats

BACKGROUND

Subarachnoid hemorrhage (SAH) is associated with neurocognitive impairment. Recent data suggest that sevoflurane attenuates edema formation after SAH in rats. However, so far, no information is available about the long-term repair phase, nor if sevoflurane impacts functionality by increasing vascularity. This study tested whether sevoflurane postconditioning would improve long-term neurologic deficit through increased formation of new vessels close to the hemorrhage area.

METHODS

Fifty-three animals were subjected to SAH or sham surgery with or without a 2-hour sevoflurane postconditioning (versus propofol anesthesia). Animal survival, including dropout animals due to death or reaching termination criteria, as well as neurologic deficit, defined by the Garcia score, were assessed 2 hours after recovery until postoperative day 14. On day 14, blood samples and brain tissue were harvested. Vessel density was determined by the number of cluster of differentiation 31 (CD31)-positive vessels, and activated glial cells by glial fibrillary acidic protein (GFAP)-positive astrocytes per field of view.

RESULTS

The survival rate for sham animals was 100%, 69% in the SAH-propofol and 92% in the SAH-sevoflurane groups. According to the log-rank Mantel-Cox test, survival curves were significantly different ( P = .024). The short-term neurologic deficit was higher in SAH-propofol versus SAH-sevoflurane animals 2 hours after recovery and on postoperative day 1 (propofol versus sevoflurane: 14. 6 ± 3.4 vs 15. 9 ± 2.7 points, P = .034, and 16. 2 ± 3.5 vs 17. 8 ± 0.9 points, P = .015). Overall complete recovery from neurologic deficit was observed on day 7 in both SAH groups (18. 0 ± 0.0 vs 18. 0 ± 0.0 points, P = 1.000). Cortical vascular density increased to 80. 6 ± 15.0 vessels per field of view in SAH-propofol animals (vs 71. 4 ± 10.1 in SAH-sevoflurane, P < .001). Activation of glial cells, an indicator of neuroinflammation, was assessed by GFAP-positive astrocytes GFAP per field of view. Hippocampal GFAP-positive cells were 201 ± 68 vs 179 ± 84 cells per field of view in SAH-propofol versus SAH-sevoflurane animals ( P < .001).

CONCLUSIONS

Sevoflurane postconditioning improves survival by 23% (SAH-sevoflurane versus SAH-propofol). The sevoflurane intervention could attenuate the early neurologic deficit, while the long-term outcome was similar across the groups. A higher vascular density close to the SAH area in the propofol group was not associated with improved outcomes.

Comorbidities and Angiogenic Regulators Affect Endothelial Progenitor Cell Subtype Numbers in a Healthy Volunteer Control Group

Endothelial progenitor cells (EPCs) are stem cells that can repair injured blood vessels through neovascularisation. This is achieved through secretion of growth factors and endothelial maturation. EPC numbers and function have been studied to determine their diagnostic, prognostic and therapeutic potential in many ischaemic diseases such as stroke. However their activation homing and migration is not definitively understood in stroke patients. In this study, we profiled the non-stroke control group recruited into the Dunhill Medical Trust Endothelial Progenitor Cell Study. Demographic, clinical and plasma levels of angiogenic regulators of participants were analysed to determine if there was any correlation with EPC numbers, subtypes and function. Participants with diabetes had significantly supressed EPC numbers (CD45-CD34 + CD133 + KDR+) and CD34 + KDR + and KDR + EPC subtypes. Male participants had significantly lower EPC numbers compared to female participants and the proliferative capacity of endothelial colony forming cells significantly decreased with increasing participant age. Pro-angiogenic proteins such as granulocyte colony-stimulating factor and stromal cell-derived factor were positively correlated with both undifferentiated and endothelial-committed EPC subtype numbers (CD133+, KDR+, CD34 + CD133+, CD34 + KDR+), whereas anti-angiogenic proteins such as thrombospondin-1 showed a negative correlation with undifferentiated EPC subtypes (CD133+, CD34 + CD133+) but a positive correlation with endothelial-committed EPC subtype numbers (KDR+, CD34 + KDR+). These results show that EPC numbers and subtypes are affected by many factors and larger studies which can analyse and deconvolute the interactions between comorbidities, plasma biomarker levels and EPC are needed.