Endothelial Cell Tube Formation Research Articles

Exosomes derived from minor salivary gland mesenchymal stem cells: a promising novel exosome exhibiting pro-angiogenic and wound healing effects similar to those of adipose-derived stem cell exosomes

BackgroundsMinor salivary gland mesenchymal stem cells (MSGMSCs) can be easily extracted and have a broad range of sources. Applying exosomes to wounds is a highly promising method for promoting wound healing. Exosomes derived from different stem cell types have been proven to enhance wound healing, with adipose-derived stem cell (ADSC)-derived exosomes being the most extensively researched. Considering that MSGMSCs have advantages such as easier extraction compared to ADSCs, MSGMSCs should also be a very promising type of stem cell in exosome therapy. However, whether MSGMSC-derived exosomes (MSGMSC-exos) can promote wound healing and how they compare to ADSC-derived exosomes (ADSC-exos) in the wound healing process remain unclear.MaterialsThe effects of MSGMSC-exos and ADSC-exos on angiogenesis in wound healing were investigated in vitro using CCK-8, scratch assays, and tube formation assays. Subsequently, the promotion of wound healing by MSGMSC-exos and ADSC-exos was evaluated in vivo using a full-thickness wound defect model in mice. Immunohistochemistry was used to verify the effects of MSGMSC-exos and ADSC-exos on promoting collagen deposition, angiogenesis, and cell proliferation in the wound. Immunofluorescence staining was performed to investigate the role of MSGMSC-exos and ADSC-exos in modulating the inflammatory response in the wound. Furthermore, proteomic sequencing was conducted to investigate the functional similarities and differences between the proteomes of MSGMSC-exos and ADSC-exos, with key protein contents verified by ELISA.ResultsMSGMSC-exos exhibited similar effects as ADSC-exos in promoting the migration, proliferation, and tube formation of human umbilical vein endothelial cells (HUVECs) in vitro, with a comparable dose-dependent effect. In vivo experiments confirmed that MSGMSC-exos have similar wound healing-promoting functions as ADSC-exos. MSGMSC-exos promoted the neovascularization and maturation of blood vessels in vivo at a level comparable to ADSC-exos. Despite MSGMSC-exos showing less collagen deposition than ADSC-exos, they exhibited stronger anti-scar formation and anti-inflammatory effects. Proteomic analysis revealed that the proteins promoting wound healing in both MSGMSC-exos and ADSC-exos were relatively conserved, with ITGB1 identified as a critical protein for angiogenesis. Further differential analysis revealed that the functions specifically enriched in MSGMSC-exos and ADSC-exos reflected the functions of their source tissue.ConclusionsOur study confirms that MSGMSC-exos exhibit highly similar wound healing and angiogenesis-promoting functions compared to ADSC-exos, and the proteins involved in promoting wound healing in both are relatively conserved. Moreover, MSGMSC-exos show stronger anti-scar formation and anti-inflammatory effects than ADSC-exos. This suggests that MSGMSCs are a promising stem cell source with broad applications in wound healing treatment.

Adipsin improves diabetic hindlimb ischemia through SERPINE1 dependent angiogenesis

BackgroundAdipsin (complement factor D, CFD), as the first described adipokine, is well-known for its regulatory effects in diabetic cardiovascular complications. However, its role in diabetic hind-limb ischemia was not clarified. This study aimed to evaluate the possible therapeutic effect of Adipsin in hind-limb ischemia in type 2 diabetic mice and to elucidate the molecular mechanisms involved.MethodsA high-fat diet and streptozotocin (HFD/STZ)-induced diabetic mouse model, and a transgenic mouse model with adipose tissue-specific overexpression of Adipsin (Adipsin-Tg) were employed. Hindlimb ischemia was established by femoral artery ligation, and blood flow recovery was monitored using Laser Doppler perfusion imaging. Molecular mechanisms underlying Adipsin-potentiated angiogenesis were examined using RNA sequencing and co-immunoprecipitation/mass spectrometry (Co-IP/MS) analyses.ResultsAdipsin expression was upregulated in non-diabetic mice following HLI, while suppressed in diabetic mice, indicating its potential role in ischemic recovery which is impaired in diabetes. Adipsin-Tg mice exhibited significantly improved blood flow recovery, increased capillary density, and enhanced muscle regeneration in comparison with non-transgenic (NTg) diabetic mice. Adipsin facilitated proliferation, migration, and tube formation of human umbilical vein endothelial cells (HUVECs) under hyperglycemic and hypoxic conditions. Additionally, it enhanced phosphorylation of AKT, ERK, and eNOS pathways both in vivo and in vitro. RNA sequencing and co-immunoprecipitation/mass spectrometry (Co-IP/MS) analyses identified that Adipsin promoted angiogenesis by interacting with SERBP1, which disrupted the binding of SERBP1 to SERPINE1 mRNA, resulting in reduced SERPINE1 expression and the subsequent activation of the VEGFR2 signaling cascade.ConclusionsAdipsin promotes angiogenesis and facilitates blood perfusion recovery in diabetic mice with HLI by downregulating SERPINE1 through interaction with SERBP1. These findings elucidate a novel therapeutic potential for Adipsin in the management of PAD in diabetic patients, highlighting its role in enhancing angiogenesis and tissue repair.

Inhibition of lysophosphatidic acid receptor 2 attenuates neonatal chronic lung disease in mice by preserving vascular and alveolar development

AimBronchopulmonary dysplasia (BPD) is a common morbidity in extremely premature infants. Previous studies demonstrated the important role of lysophosphatidic acid (LPA) in inflammation in BPD. However, the role of LPA and its receptors in hyperoxia-induced vascular malformations in BPD remains to be elucidated. Methods and ResultsElevated plasma LPA levels were observed in mice with BPD compared to controls (792 vs. 607 ng/mL, p < 0.05). Inhibition of LPA signaling protected against hyperoxia-induced lung injury in neonatal mice, demonstrated by a 2.8-fold increase in pulmonary vascular density and a 14% reduction in alveolar enlargement. In vitro studies showed that LPA suppressed tube formation in human umbilical vein endothelial cells (HUVECs) by approximately 50%. LPA receptor 2 (LPA2) was identified as a functional LPA receptor in primary endothelial cells from the lungs of hyperoxic mice and in HUVECs under hyperoxic conditions. The LPA2 antagonist H2L5186303 enhanced the tube formation ability of HUVECs exposed to LPA, both under normoxia (4-fold) and hyperoxia (5-fold). Moreover, H2L5186303 significantly protected against hyperoxia-induced vascular malformation (2-fold) and improved alveolarization in neonatal mice (12% decrease in mean linear intercept, MLI). Early growth response 1 (EGR1) was characterized as a downstream target of LPA2, silencing EGR1 restored tube formation in HUVECs exposed to LPA and hyperoxia. ConclusionsOur in vitro and in vivo findings demonstrate that the inhibition of LPA/LPA2 signaling mitigates hyperoxia-induced pulmonary vascular malformations, suggesting the LPA/LPA2-dependent signaling pathway has therapeutic potential for extremely premature infants with BPD.

A multi-purpose dressing based on resveratrol-loaded ionic liquids/gelatin methacryloyl hydrogel for enhancing diabetic wound healing

Diabetic wound (DW) is a multifaceted challenge, characterized by persistent bacterial infections and compromised angiogenesis. To address these issues and enhance DW healing, we developed a novel strategy using a photo-crosslinked hydrogel system composed of ionic liquids (ILs) and gelatin methacryloyl (GelMA) loaded with resveratrol (Res). The ILs/GelMA hydrogel was fabricated via a simple photo-crosslinking process, resulting in desirable mechanical properties, biocompatibility, and controlled release kinetics. Res was incorporated into the hydrogel matrix (ILs/GelMA@Res) to ensure sustained release, facilitating angiogenesis and accelerating wound healing. In vitro studies demonstrated that the ILs/GelMA@Res hydrogel exhibited potent antibacterial activity against Staphylococcus aureus and Escherichia coli, inhibiting bacterial growth and biofilm formation. Furthermore, the sustained release of Res from the hydrogel promoted angiogenesis by activating the PI3K/AKT signaling pathways associated with VEGF and FGF, enhancing endothelial cell proliferation, migration, and tube formation. In a DW mice model, the ILs/GelMA@Res hydrogel demonstrated accelerated wound closure, reduced inflammation, and robust neovascularization. This multifunctional hydrogel-based delivery system holds considerable potential for clinical translation, offering a safe and effective treatment modality for diabetic patients with chronic wounds.

Collagen Hydrogel Loaded With 9-cisRA-Lip Is an Option for Treatment of Secondary Lymphedema after Surgery.

Background: Secondary upper limb lymphedema is easy to occur after breast cancer surgery, for which treatment is limited. 9-cis-retinoic acid (9-cisRA) has been demonstrated to increase lymphangiogenesis without enhancing tumor metastasis but has the disadvantages of poor water solubility, easy decomposition in light, unstable to heat, and short half-life. Methods: Based on this, 9-cisRA-Lip with a particle size of roughly 143 nm and high dispersibility was prepared by thin-film dispersion method and verified by Malvern Laser Particle Size Analyzer and electron microscopy. Results: In vitro, 9-cisRA-Lip demonstrated good biosafety and tumor safety, promoting the proliferation of L929 cells while having no effect on 4T1 and Human Umbilical Vein Endothelial (HUVEC) cells. Compared with 9-cisRA, 9-cisRA-Lip was more effective at encouraging mouse lymphatic endothelial cell (SVEC4-10) migration, proliferation, and tube formation. In vivo, 9-cisRA-Lip-Gel showed good slow-release effect, mice treated with 9-cisRA-Lip-Gel one-time local injection had considerably less tail edema than the control group from day 9 to day 39 postsurgery (p < 0.05). This may be attributed to the greater capacity of 9-cisRA-Lip to enhance the phosphorylation of FGFR3 (Fibroblast Growth Factor Receptor 3) at Tyr 724. Conclusions: 9-cisRA-Lip-Gel presents a potential treatment option for lymphedema following surgery.

Anti‑angiogenic effect of Bryopsis plumosa‑derived peptide via aquaporin 3 in non‑small cell lung cancer.

Developing novel anti‑angiogenic agents with minimal toxicity is notably challenging for cancer therapeutics. The discovery and development of peptides, whether derived from natural sources or synthesized, has potential for developing anti‑angiogenic agents characterized by their ability to penetrate cancer cells, high specificity and low toxicity. The present study identified a Bryopsis plumose‑derived anticancer and anti‑angiogenesis marine‑derived peptide 06 (MP06). A 22‑amino acid peptide was synthesized and conjugated with fluorescein isothiocyanate (FITC‑MP06) for intracellular localization in H1299 non‑small cell lung cancer cells. Regulatory effects of this peptide on the viability, migration and self‑renewal of lung cancer cells was assessed. Furthermore, anti‑angiogenic effect of MP06 was investigated by monitoring vascular tube formation in human umbilical vein endothelial cells and a zebrafish model. Aquaporin (AQP)3, a membrane channel in various tissues, is involved in regulating stemness, epithelial‑mesenchymal transition (EMT) and angiogenesis. MP06 downregulated AQP3 expression. Consistently, AQP3 knockdown by RNA silencing downregulated its gene expression, leading to a decrease in stemness, EMT and angiogenesis properties in H1299 cells. MP06 could thus serve as a novel therapeutic target with anticancer and angiogenesis properties for non‑small cell lung cancer.

Serum small extracellular vesicles-derived BST2 as a biomarker for papillary thyroid microcarcinoma promotes lymph node metastasis.

Papillary thyroid microcarcinoma (PTMC), although frequently indolent, could be aggressive in a few patients, leading to lymph node metastasis (LNM) and worsened prognosis. To explore the role of protein profiling of small extracellular vesicles (sEVs) in the auxiliary diagnosis and risk stratification of PTMC, proteins in serum sEVs isolated from PTMC patients with (N = 10) and without (N = 10) LNM and benign thyroid nodule (BN) patients (N = 9) were profiled via a bioinformatics-integrated data-independent acquisition proteomic technique. The performance of candidate proteins as diagnostic and prognostic biomarkers in PTMC was assessed via receiver operating characteristic analysis. We found that serum sEVs from PTMC patients promoted the proliferation and migration of human papillary thyroid cancer (PTC) cells and tube formation in human lymphatic endothelial cells (HLECs). SEV proteins from PTMC patients with and without LNM have differential expression profiles, with bone marrow stromal cell antigen 2 (BST2) being best associated with PTMC progression. Through knockdown and overexpression, we proved that the high expression of sEV-derived BST2 was bound up with higher proliferation and migration ability of PTC cells as well as stronger lymphangiogenesis in HLECs. This study brought insight into the differential sEV-protein profile with or without LNM in PTMC. The serum sEV-BST2 may contribute to PTMC progression and LNM and may have diagnostic, prognostic, and therapeutic implications.

Chitosan microcarriers loaded with functional drug for stimulating osteogenesis and angiogenesis in vitro

Angiogenesis-osteogenesis coupling plays important roles in bone regeneration; therefore, biomaterials capable of stimulating both osteogenesis and angiogenesis show significant influence in bone repair. Herein, chitosan (CS) microcarriers loaded with functional drug dimethyloxalylglycine (DMOG) were prepared using the emulsion phase separation and impregnation method for stimulating osteogenesis and angiogenesis. FTIR and zeta potential analyses confirmed successful DMOG loading into CS microcarriers, primarily through physical adsorption, particularly hydrogen-bond interaction. As the impregnation concentration of DMOG increased, the amounts of DMOG loaded into the microcarriers increased, while the drug encapsulation efficiency decreased. All microcarriers, ranging in size from 200 to 400 μm, revealed quasi-spherical shapes and an interconnected porous structure with pore sizes mainly between 15 and 30 μm, suitable for cell attachment and proliferation. The introduction of DMOG increased the residues of the microcarriers during thermogravimetric analysis. CS/DMOG microcarriers exhibited sustained drug release (for >19 days) and good degradation ability. Furthermore, CS/DMOG microcarriers supported stem cell adhesion and proliferation. They also enhanced stem cell osteogenesis verified by strengthening alkaline phosphatase expression and mineralization. Moreover, they promoted angiogenesis, as evidenced by stimulating endothelial cell migration and tube formation. These results suggest that CS/DMOG microcarriers have the potential to be used for bone tissue regeneration.

Harnessing synergistic effects of MMP-2 Inhibition and bFGF to simultaneously preserve and vascularize cardiac extracellular matrix after myocardial infarction

Myocardial infarction (MI) leads to cardiac extracellular matrix (ECM) degradation and fibrosis, reducing heart function. Consequently, simultaneously addressing ECM degradation and inhibiting cardiac fibrosis is essential for preserving heart function and mitigating adverse remodeling. However, the preserved ECM becomes unstable if not vascularized, as its structure and composition undergo changes over time. ECM vascularization is crucial to improve cardiac function. Presently, there is no clinically approved therapy that can simultaneously preserve and vascularize the ECM, and inhibit cardiac fibrosis. Our study develops a drug delivery system aiming to achieve these goals. It includes the peptide CTTHWGFTLC (CTT), a specific MMP-2 inhibitor, and basic fibroblast growth factor (bFGF), a potent factor with pro-angiogenic and anti-fibrotic properties. An injectable hydrogel serves as the carrier, featuring a rapid gelation that allows for the substantial retention of drugs. Additionally, the hydrogel has the capability to scavenge upregulated reactive oxygen species (ROS), thereby reducing tissue inflammation. Our findings indicate that CTT and bFGF synergistically enhance endothelial cell migration and tube formation while inhibiting the differentiation of fibroblasts into myofibroblasts. Upon delivery into hearts, the system significantly decreases MMP-2 level, promotes angiogenesis, attenuates cardiac fibrosis, and alleviates inflammation, resulting in a noteworthy cardiac function improvement. Statement of significance1) This work addresses key challenges in cardiac repair after myocardial infarction (MI), including extracellular matrix (ECM) degradation, vascularization, and fibrosis. 2) We combined an MMP-2/9 inhibitor (CTT) with bFGF to prevent ECM degradation, enhance vascularization, and inhibit fibrosis, providing a comprehensive strategy to improve cardiac function. 3) An injectable hydrogel was developed with rapid gelation and mechanical properties similar to heart tissue, ensuring efficient drug retention and reducing tissue stress. 4) The hydrogel enabled controlled, spatiotemporal release of CTT to dynamically reduce MMP-2/9 activity, and gradually released bFGF to promote angiogenesis and inhibit fibrosis.

Histone Deacetylase 7-Derived 7-Amino Acid Peptide Increases Skin Wound Healing via Regulating Epidermal Fibroblast Proliferation and Migration.

Due to the complexity of wound healing, how to achieve successful healing is a significant clinical challenge. In this study, we found that the histone deacetylase-7-derived 7-amino acid peptide (7A, MHSPGAD), especially its phosphorylated version 7Ap (MH[pSer]PGAD), increased dermal fibroblast cell HDFα proliferation and migration via elevated delta-catenin (CTNND1) serine phosphorylation-mediated beta-catenin (CTNNB) nuclear translocation and subsequent upregulation of c-Myc and cyclin D1 expression. 7Ap physically interacted with platelet-derived growth factor receptor (PDGFR) and increased PDGFR interaction with cyclin-dependent kinase 6 (CDK6). The PDGFR siRNA or CDK6 siRNA knockdown ablated 7AP-induced CTNND1 phosphorylation and subsequent c-Myc/cyclin D1 expression, indicating a novel 7Ap-PDGFR-CDK6-CTNND1/CTNNB signal pathway in regulating fibroblast proliferation and migration. Furthermore, 7Ap increased human umbilic vein endothelial cell proliferation and tube formation, suggesting an angiogenic effect. In a full-thickness excision wound rat model, the local administration of 50 ng/mL of 7Ap in hydrogel exerted a similar effect as 1 μg/mL vascular endothelial growth factor on accelerating wound healing, featured by enhanced fibroblast proliferation and migration, collagen deposition, and increased new vessel formation during the early phase of wound healing. Taken together, this study not only elicited a novel signal pathway in fibroblast proliferation but also paved an avenue to develop 7Ap as a treatment option for skin wound healing.

The angiogenic role of the alpha 9-nicotinic acetylcholine receptor in triple-negative breast cancers.

Nicotine acts as an angiogenic factor by stimulating endogenous cholinergic pathways. Several subtypes of nicotinic acetylcholine receptors (nAChRs) have been demonstrated to be closely correlated to the formation and progression of different types of cancers. Recently, several studies have found that nicotinic acetylcholine receptors α9 (α9-nAChRs) are highly expressed in breast tumors, especially in tumors derived from patients diagnosed at advanced stages. In vitro studies have demonstrated that activation of α9-nAChRs is associated with increased proliferation and migration of breast cancer. To study the tumor-promoting role of α9-nAChRs in breast cancers, we generated a novel anti-α9-nAChR and methoxy-polyethylene glycol (mPEG) bispecific antibody (α9 BsAb) for dissecting the molecular mechanism on α9-nAChR-mediated tumor progression. Unexpectedly, we discovered the angiogenic role of α9-nAChR in nicotine-induced neovascularization of tumors. It revealed α9 BsAbs reduced nicotine-induced endothelial cell tube formation, blood vessel development in Matrigel plug assay and angiogenesis in microtube array membrane murine model (MTAMs). To unbraid the molecular mechanism of α9-nAChR in nicotine-mediated angiogenesis, the α9 BsAbs were applied and revealed the inhibitory roles in nicotine-induced production of hypoxia-inducible factor-2 alpha (HIF-2α), vascular endothelial growth factor A (VEGF-A), phosphorylated vascular endothelial growth factor receptor 2 (p-VEGFR2), vascular endothelial growth factor receptor 2 (VEGFR2) and matrix metalloproteinase-9 (MMP9) from triple-negative breast cancer cells (MDA-MB-231), suggesting α9-nAChRs played an important role in nicotine-induced angiogenesis. To confirm our results, the shRNA targeting α9-nAChRs was designed and used to silence α9-nAChR expression and then evaluated the angiogenic role of α9-nAChRs. The results showed α9 shRNA also played an inhibitory effect in blocking the nicotine-induced angiogenic signaling. Taken together, α9-nAChR played a critical role in nicotine-induced angiogenesis and this bispecific antibody (α9 BsAb) may serve as a potential therapeutic candidate for treatments of the α9 positive cancers.

Targeting the histone methyltransferase SETD7 rescues diabetes-induced impairment of angiogenic response by transcriptional repression of semaphorin 3G

Abstract Background Peripheral artery disease (PAD) is highly prevalent in patients with diabetes (DM) and associates with a high rate of limb amputation and poor prognosis. Surgical and catheter-based revascularization have failed to improve outcome in DM patients with PAD. Hence, a need exists to develop new treatment strategies able to promote blood vessel growth in this setting. Mono-methylation of histone 3 at lysine 4 (H3K4me1) - a specific epigenetic signature induced by the histone methyltransferase SETD7 - favours an open chromatin thus enabling gene transcription. Purpose To investigate whether SETD7-dependent epigenetic changes modulate angiogenic response in diabetes. Methodology Primary human aortic endothelial cells (HAECs) were exposed to normal glucose (NG, 5 mM) or high glucose (HG, 25 mM) concentrations for 48 hours. Unbiased gene expression profiling was performed by RNA sequencing (RNA-seq) followed by Ingenuity Pathway Analysis (IPA). In vitro assays, namely cell migration and tube formation were employed to study angiogenic properties in HAECs. SETD7 and H3K4me1 levels were investigated by Western blot and Chromatin immunoprecipitation (ChIP). Pharmacological blockade of SETD7 was achieved by using the highly selective inhibitor (R)-PFI-2. Mice with streptozotocin-induced diabetes were orally treated with (R)-PFI-2 or vehicle and underwent hindlimb ischemia by femoral artery ligation for 14 days. Blood flow recovery was analysed at 30 minutes, 7 and 14 days by laser Doppler imaging. Our experimental findings were also translated in gastrocnemius muscle samples from patients with and without diabetes. Results RNA-seq in HG-treated HAECs revealed a profound upregulation of the methyltransferase SETD7, an enzyme involved in mono-methylation of lysine 4 at histone 3 (H3K4me1). SETD7 upregulation in HG-treated HAECs was associated with increased H3K4me1 levels as well as with impaired endothelial cell migration and tube formation. Both SETD7 gene silencing and pharmacological inhibition by (R)PFI-2 rescued hyperglycemia-induced impairment of HAECs migration and tube formation, while SETD7 overexpression blunted the angiogenic response. RNA-seq and ChIP assays showed that SETD7-dependent H3K4me1 regulates the transcription of the angiogenesis inhibitor semaphorin-3G (SEMA-3G). Moreover, SEMA-3G overexpression blunted migration and tube formation in SETD7-depleted HAECs. In diabetic mice with hindlimb ischemia, treatment with (R)-PFI-2 improved limb vascularization and perfusion as compared to vehicle. Finally, SETD7/SEMA3G axis was upregulated in muscle specimens from T2D patients as compared to controls. Conclusion Targeting SETD7 represents a novel epigenetic-based therapy to boost neovascularization in diabetic patients with PAD.

Extracellular vesicle-incorporated long noncoding RNA PUNISHER is increased in coronary artery disease and regulates endothelial cell function

Abstract Aims Long noncoding RNAs (lncRNAs) have emerged as biomarkers and regulators of cardiovascular disease. Circulating lncRNAs can be incorporated into extracellular vesicles (EVs). Our aim was to study the expression pattern of circulating EV-incorporated lncRNAs in patients with and without coronary artery disease (CAD). The regulation of the lncRNA PUNISHER was further assessed as an intercellular messenger in endothelial cell (EC) biology. Methods and results Circulating EVs were isolated from the plasma of patients using ultracentrifugation. Electron microscopy, western blot, and NTA were used to determine the size and origin of the EVs. PCR-based human lncRNA array analysis revealed that certain EV-lncRNAs are significantly different in patients with CAD compared to patients without CAD. To validate the lncRNA array results, 60 patients with (n=30) or without (n=30) CAD were prospectively studied. Four atherosclerosis-related lncRNAs (PUNISHER, GAS5, MALAT1, and H19) were quantified in the circulating EVs by using real-time quantitative PCR (RT-qPCR). Among these, PUNISHER (p=0.002) and GAS5 (0.02) were significantly increased in patients with CAD, compared to non-CAD patients. Analysis of RNA degradation revealed that circulating PUNISHER is mainly incorporated within EVs. In vitro, atherosclerotic stimuli consisting of oxLDL or TNF-a treatment caused an upregulation of PUNISHER levels in human coronary artery endothelial cells (HCAEC) and in the corresponding EVs. Labeling of EVs followed by RT-qPCR demonstrated that functional PUNISHER was transported into the recipient ECs, which accelerated cell migration, proliferation, and tube formation. Mechanistically, the RNA-binding protein hnRNPK was identified by an RNA immunoprecipitation (RIP) assay as an interaction partner of PUNISHER, regulating its loading into small EVs. Knockdown of PUNISHER abrogated the EV-mediated effects on EC migration, proliferation, and tube formation. PCR-based gene profiling showed that the expression of VEGF RNA was significantly increased in ECs by treatment with EVs. Protein stability and RNA-immunoprecipitation followed by RT-qPCR analysis indicated that the PUNISHER-hnRNPK axis regulates the stability and binding of VEGFA mRNA to hnRNPK. Knockdown of PUNISHER in EVs abrogated the EV-mediated promotion of VEGFA gene- and protein expression. Conclusion The circulating lncRNA PUNISHER is increased in CAD patients. Intercellular transfer of EV-incorporated PUNISHER promotes a pro-angiogenic phenotype via a VEGFA-dependent mechanism.

Colorectal Cancer Cell-Derived Extracellular Vesicles Promote Angiogenesis Through JAK/STAT3/VEGFA Signaling.

Angiogenesis plays a crucial role in the growth of colorectal cancer (CRC). Recent studies have identified extracellular vesicles (EVs) in the tumor microenvironment as important mediators of cell-to-cell communication. However, the specific role and mechanisms of CRC-derived EVs in regulating tumor angiogenesis remain to be further investigated. EVs were isolated from the conditioned medium of the CRC cells using ultracentrifugation. We investigated the effects of HT-29-derived EVs on tumor growth and angiogenesis in a subcutaneous HT-29 CRC tumor model in mice. Additionally, we evaluated the impact of HT-29-derived EVs on the proliferation, migration, and tube formation of human umbilical vein endothelial cells (HUVECs). Subsequently, bioinformatics analysis was performed to identify relevant signaling pathways, and pathway inhibitors were used to block the activation of these pathways, aiming to elucidate their roles in angiogenesis. We found that HT-29-derived EVs can promote tumor growth and angiogenesis in vivo, as well as significantly enhance the proliferation, migration, and tube formation of HUVECs. Bioinformatics analysis revealed that HT-29-derived EVs may regulate angiogenesis through the JAK/STAT3 signaling pathway. Specifically, we observed that CRC-derived EVs promoted the phosphorylation of STAT3 (p-STAT3) and the expression of VEGFA in the nucleus of HUVECs. Treatment with the STAT3 inhibitor Stattic reduced the nuclear expression of p-STAT3, which impaired its function as a transcription factor, thereby inhibiting VEGFA expression and the pro-angiogenic effects of CRC-derived EVs. EVs derived from CRC cells promote CRC tumor angiogenesis by regulating VEGFA through the JAK/STAT3 pathway in endothelial cells.

CD90's role in vascularization and healing of rib fractures: insights from Dll4/notch regulation.

Vascularization after rib fracture is a crucial physiological process that is essential for the repair and healing of the rib. Studies have shown that CD90 plays a critical role in regulating rib fracture healing, but the underlying mechanism of its role has not been fully elucidated. CD90 adenovirus knockout mice were used to construct a rib injury model. The bone healing was observed by micro-CT. CD31/EMCN immunofluorescence staining was performed on bone tissue to observe the density of H-shaped and L-shaped blood vessels at the site of bone injury. CD31 and EMCN dual-stained single cells from the rib fracture sites were detected by flow cytometry. The periosteal stem cells transfected with CD90 or Notch1 overexpression and silencing vector were co-cultured with osteoblast MC3T3-E1 in osteogenic induction medium. Moreover, bone microvascular endothelial cells were extracted from the rib injury and co-cultured with the periosteal stem cells transfected with CD90. CCK-8 was used to detect cell viability, RT-qPCR and Western blot were used to detect Notch1, Notch2, Notch3, Notch4, CD31, HIF-1α, CD90, RUNX2, OCN and OPN expression. Alkaline phosphatase (ALP) staining and alizarin red staining were used to observe mineralized nodules. Immunofluorescence staining was used to detect the expression of Dll4, Notch, and CD90 in each group of cells. The angiogenesis experiment was conducted to observe cellular vascular formation. Compared with the Adsh-NC group, the bone healing in the Adsh-CD90 group was significantly impaired, with a marked reduction in the number and volume of blood vessels at the rib fracture site, as evidenced by CD31/EMCN immunofluorescence staining, which showed a reduction in the number of H type vessels at the site of bone injury. It was found that CD90 depletion can inhibit the signaling of Dll4/Notch in the rib fracture site. Furthermore, we found that overexpression of Notch1 reverses the impairment of tubule formation in bone microvascular endothelial cells caused by CD90 suppression.r.Dll4 protein reverses the inhibitory effect of CD90 deletion on periosteal stem cells and MC3T3-E1 cell viability and osteogenesis. In the end, we found that overexpression of Notch1 and CD90 can promote angiogenesis of bone microvascular endothelial cells and Notch pathway activation. CD90 can affect vascular formation in mouse rib fractures, and CD90 may be regulated by Dll4/Notch.

Genetically Engineered Filamentous Bacteriophages Displaying TGF-β1 Promote Angiogenesis in 3D Microenvironments.

Combined 3D cell culture in vitro assays with microenvironment-mimicking systems are effective for cell-based screening tests of drug and chemical toxicity. Filamentous bacteriophages have diverse applications in material science, drug delivery, tissue engineering, energy, and biosensor development. Specifically, genetically modified bacteriophages have the potential to deliver therapeutic molecules or genes to targeted tumor tissues. The engineered bacteriophages in this study significantly enhanced endothelial cell migration and tube formation within the extracellular matrix (ECM). Compared to TGF-β1 alone and non-modified phages, the presence of TGF-β1 on the bacteriophages demonstrated superior performance as a continuous stimulant in the microenvironment, effectively promoting these angiogenic processes. Assays, including RT-qPCR, ELISA, and fluorescence microscopy, confirmed the expression of angiogenic markers such as CD31, validating the formation of 3D angiogenic structures. Our findings indicate that the TGF-β1 displayed by bacteriophages likely acted as a chemotactic factor, promoting the migration, proliferation, and tube formation of endothelial cells (ECs) within the ECM. Although direct contact between ECs and bacteriophages was not explicitly confirmed, the observed effects strongly suggest that TGF-β1-RGD bacteriophages contributed to the stimulation of angiogenic processes. The formation of angiogenic structures by ECs in the ECM was confirmed as three-dimensional and regulated by the surface treatment of microfluidic channels. These results suggest that biocompatible TGF-β1-displaying bacteriophages could continuously stimulate the microenvironment in vitro for angiogenesis models. Furthermore, we demonstrated that these functionalized bacteriophages have the potential to be utilized as versatile biomaterials in the field of biomedical engineering. Similar strategies could be applied to develop angiogenic matrices for tissue engineering in in vitro assays.

Multifunctional carboxymethyl chitosan/oxidized carboxymethyl cellulose hydrogel loaded with ginsenoside Rg1 and polydopamine nanoparticles for infected diabetic wound healing

Besides bacterial infection, diabetic wounds are often accompanied by local inflammatory response, oxidative stress imbalances, and vascular formation disorders, which are the main reasons for long-term non-healing of diabetic wounds. In order to solve this problem, Ch-OCMC-PDA NPs-Rg1 self-healing hydrogel was constructed by Schiff base reaction. With the addition of PDA NPs and Rg1, Ch-OCMC-PDA NPs-Rg1 hydrogel showed excellent physical properties, like compressive strength of 142 kPa, swelling ratio of 148.91 %, and Rg1 carried in the hydrogel could achieve a slow release of 90.59 % within 48 h. What's more, PDA NPs endowed it with highly efficient photothermal antibacterial properties. In addition to excellent biocompatibility, Ch-OCMC-PDA NPs-Rg1 hydrogel could effectively clear intracellular reactive oxygen species, promote macrophages M2 transformation, and facilitate human umbilical vein endothelial cells migration and tube formation. In vivo experiments exhibited that Ch-OCMC-PDA NPs-Rg1 hydrogel could reduce wound inflammation, stimulate early angiogenesis, promote collagen deposition, and shorten the healing process of diabetic infected wounds, and the wound healing rate was significantly increased compared with other groups, reaching 98.41 ± 0.31 %. In summary, the multi-functional dynamic Ch-OCMC-PDA NPs-Rg1 hydrogel provides a new possibility for the treatment of diabetic infection wounds.

Differential Effects of Four Canonical Notch-Activating Ligands on c-Kit+ Cardiac Progenitor Cells.

Notch signaling, an important signaling pathway in cardiac development, has been shown to mediate the reparative functions of c-kit+ progenitor cells (CPCs). However, it is unclear how each of the four canonical Notch-activating ligands affects intracellular processes in c-kit+ cells when used as an external stimulus. Neonatal c-kit+ CPCs were stimulated using four different chimeric Notch-activating ligands tethered to Dynabeads, and the resulting changes were assessed using TaqMan gene expression arrays, with subsequent analysis by principal component analysis (PCA). Additionally, functional outcomes were measured using an endothelial cell tube formation assay and MSC migration assay to assess the paracrine capacity to stimulate new vessel formation and recruit other reparative cell types to the site of injury. Gene expression data showed that stimulation with Jagged-1 is associated with the greatest pro-angiogenic gene response, including the expression of VEGF and basement membrane proteins, while the other canonical ligands, Jagged-2, Dll-1, and Dll-4, are more associated with regulatory and epigenetic changes. The functional assay showed differential responses to the four ligands in terms of angiogenesis, while none of the ligands produced a robust change in migration. These data demonstrate how the four Notch-activating ligands differentially regulate CPC gene expression and function.

Experimental study on repairing rat abdominal wall defect with chitosan hydrogel/polypropylene mesh composite

To investigate the improvement effects and mechanisms of composite chitosan (CS) hydrogel on traditional polypropylene (PP) mesh for repairing abdominal wall defects. CS hydrogel was prepared via physical cross-linking and then combined with PP mesh to create a CS hydrogel/PP mesh composite. The internal structure and hydrophilicity of the composite were characterized using macroscopic observation, upright metallographic microscope, scanning electron microscopy, and water contact angle measurements. The performance of the composite (experimental group) in resisting cell adhesion and supporting cell infiltration was assessed through fibroblast (NIH-3T3) infiltration experiments and human umbilical vein endothelial cells (HUVECs) tube formation assays, and simple cells were used as control group. Finally, a bilateral abdominal wall defect model (1.5 cm×1.0 cm) was established in 18 Sprague Dawley rats aged 8-10 weeks, with the composite used on one side (experimental group) and PP mesh on the other side (control group). The effects on promoting wound healing, preventing adhesion, angiogenesis, and anti-inflammation were investigated through macroscopic observation, histological staining (HE and Masson staining), and immunohistochemical staining (CD31, CD68). The composite appeared as a pale yellow, transparent solid with a thickness of 2-3 mm, with the PP mesh securely encapsulated within the hydrogel. Scanning electron microscopy revealed that the hydrogel contained interconnected pores measuring 100-300 μm, forming a porous structure. Contact angle measurements indicated that CS hydrogel exhibited good hydrophilicity, while PP mesh was highly hydrophobic. In vitro cell culture experiments showed that DAPI staining indicated fewer positive cells in the experimental group after 1 day of culture, while the cells in control group covered the entire well plate. After 3 days of culture, the cells in experimental group were spherical and displayed uneven fluorescence, suggesting that the material could reduce cell adhesion while supporting cell infiltration. HUVECs tube formation experiments demonstrated an increase in cell numbers in experimental group with a trend towards tube formation, while cells in control group were sparsely distributed and showed no migration. In the rat abdominal wall defect repair experiment, results showed that after 1 week post-surgery, the experimental group had tissue and blood vessels infiltrating, and by 4 weeks, the integrity was well restored with significant regeneration of muscle and blood vessels, while the control group exhibited adhesions and incomplete healing. HE staining results indicated weaker cell infiltration in the experimental group, with cell density significantly higher than that of the control group at 2 and 4 weeks post-surgery ( P<0.05). Masson staining revealed that collagen fibers in the experimental group were arranged neatly, with significantly increased collagen content at 2 weeks post-surgery ( P<0.05), while collagen content was similar in both groups at 4 weeks ( P>0.05). Immunohistochemical staining showed that CD31-positive cells were evenly distributed between muscle layers in the experimental group, whereas the control group exhibited notable defects. At 2 weeks after operation, the CD31-positive cell ratio was significantly higher than that in the control group ( P<0.05); at 2 and 4 weeks after operation, the CD68-positive cell ratio in the experimental group was significantly lower than that in the control group ( P<0.05). CS hydrogel has a positive effect on preventing adhesions and promoting wound healing, exhibiting anti-inflammatory and pro-angiogenic properties during the healing process. This provides a promising strategy to address challenges related to abdominal adhesions and reconstruction.

Exosomes from hypoxic urine-derived stem cells facilitate healing of diabetic wound by targeting SERPINE1 through miR-486-5p

Vascular pathologies and injuries are important factors for the delayed wound healing in diabetes. Previous studies have demonstrated that hypoxic environments could induce formation of new blood vessels by regulating intercellular communication and cellular behaviors. In this study, we have enhanced the angiogenic potential of exosomes by subjecting urine-derived stem cells (USCs) to hypoxic preconditioning. To prolong the retention of exosomes at the wound site, we have also engineered a novel dECM hydrogel termed SISMA, which was modified from porcine small intestinal submucosa (SIS). For its rapid and controllable gelation kinetics, excellent biocompatibility, and exosome release capability, the SISMA hydrogel has proven to be a reliable delivery vehicle for exosomes. The hypoxia-induced exosomes-loaded hydrogel has promoted endothelial cell proliferation, migration, and tube formation. More importantly, as evidenced by significant in vivo vascular regeneration in the early stages post-injury, it has facilitated tissue repair. This may because miR-486–5p in H-exo inhibit SERPINE1 activity in endothelial cell. Additionally, miRNA sequencing analysis suggested that the underlying mechanism for enhanced angiogenesis may be associated with the activation of classical HIF-1α signaling pathway. In summary, our study has presented a novel non-invasive, cell-free therapeutic approach for accelerating diabetes wound healing and development of a practical and efficient exosomes delivery platform.