Search

Ethnopharmacological Relevance: Quan-du-zhong capsule (QDZ), derived from the whole plant extract of Eucommiaulmoides Oliv., is a traditional Chinese herbal medicine used in treating vascular-related diseases, including hypertension and osteoporosis. Despite its established uses, its pro-angiogenic effects and underlying mechanisms require further investigation., Aim of This Study: This study aims to investigate the pro-angiogenic effects of QDZ and explore the underlying mechanisms., Materials and Methods: The chemical compositions of QDZ, including its absorbed prototypes in rats, were analyzed using UHPLC-Q Exactive-Orbitrap-MS. The pro-angiogenic activities of QDZ were evaluated in human umbilical vein endothelial cells (HUVECs) through various assays, including CCK-8, migration, scratch, tubule formation, and 3D sprouting assays. Additionally, the pro-angiogenic effects of QDZ were further assessed invivo through the matrigel plug assay and a hindlimb ischemia-reperfusion model, with three-dimensional blood flow visualized via micro-CT. A comprehensive approach involving network pharmacology, molecular docking, transcriptomics, and proteomics was utilized to explore the pro-angiogenic mechanism of QDZ, with validation by Western blot analysis., Results: QDZ significantly promoted the proliferation, migration, and tubule formation of HUVECs. The matrigel plug assay further confirmed its pro-angiogenic potential. Invivo, QDZ-treated mice displayed enhanced vascular distribution and faster blood flow recovery post-ischemia-reperfusion. Chemical analysis identified 49 compounds in QDZ, with 16 absorbed prototypes detected in rat plasma. Mechanistic investigations through network pharmacology, transcriptomics, and proteomics suggested that QDZ's pro-angiogenic effects were mediated through the VEGFA/PI3K-Akt signaling pathway, with increased phosphorylation of angiogenesis-related proteins such as PI3K, Akt, FAK, and Src., Conclusions: This study demonstrates that QDZ promotes angiogenesis via activating the VEGFA and its downstream PI3K-Akt signaling pathway, shedding light on the mechanisms that underpin its traditional medicinal use in vascular health., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Icariin (ICA) serves as the primary biologically active compound in traditional Chinese medicine Epimedium, while Icariside II (ICSII) represents one of its gastrointestinal metabolites. Although ICA and ICSII have demonstrated osteogenic differentiation- promoting effects on BMSCs, there is limited literature comparing their effects and underlying mechanisms. This study aimed to compare the osteogenic effects of Icariin and Icariside II, along with their respective osteogenic mechanisms. In this study, we initially determined the optimal concentrations of Icariin (10 -5 mol/L) and Icariside II (10 -6 mol/L) for inducing rBMSCs osteogenic differentiation using CCK8, ALP activity assay, and flow apoptosis assay. Subsequently, we compared the vascularization and osteogenic capacity of the two groups through alizarin red staining assay, Western Blot, and RT-PCR. Subsequently, we assessed the phosphorylated and non-phosphorylated expression of JNK, ERK1/2, P38, and AKT at different time intervals. We observed their phosphorylated expression and the expression of angiogenic/osteogenic markers after blocking with their corresponding inhibitors. It was observed that both the Icariin and Icariside II groups promoted the expression of osteogenic/angiogenic markers RUNX2, OCN, OPN, VEGF, and ANG1. While there was no significant difference in their osteogenic abilities, ICSII exhibited a stronger promotion of angiogenic differentiation markers, VEGF, compared to ICA. Additionally, it was observed that both ICA and ICSII could activate ERK1/2 phosphorylation, thereby further promoting the osteogenic/angiogenic differentiation of rBMSCs through the activation of the MAPK/ERK1/2 signaling pathway., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Diabetes mellitus can cause impaired and delayed wound healing, leading to lower extremity amputations; however, the mechanisms underlying the regulation of vascular endothelial growth factor-dependent (VEGF-dependent) angiogenesis remain unclear. In our study, the molecular underpinnings of endothelial dysfunction in diabetes are investigated, focusing on the roles of disabled-2 (Dab2) and Forkhead box M1 (FOXM1) in VEGF receptor 2 (VEGFR2) signaling and endothelial cell function. Bulk RNA-sequencing analysis identified significant downregulation of Dab2 in high-glucose-treated primary mouse skin endothelial cells. In diabetic mice with endothelial deficiency of Dab2, in vivo and in vitro angiogenesis and wound healing were reduced when compared with wild-type diabetic mice. Restoration of Dab2 expression by injected mRNA-containing, LyP-1-conjugated lipid nanoparticles rescued impaired angiogenesis and wound healing in diabetic mice. Furthermore, FOXM1 was downregulated in skin endothelial cells under high-glucose conditions as determined by RNA-sequencing analysis. FOXM1 was found to bind to the Dab2 promoter, regulating its expression and influencing VEGFR2 signaling. The FOXM1 inhibitor FDI-6 reduced Dab2 expression and phosphorylation of VEGFR2. Our study provides evidence of the crucial roles of Dab2 and FOXM1 in diabetic endothelial dysfunction and establishes targeted delivery as a promising treatment for diabetic vascular complications.

The management of diabetic wounds faces significant challenges due to the excessive activation of reactive oxygen species (ROS), dysregulation of the inflammatory response, and impaired angiogenesis. A substantial body of evidence suggests that the aforementioned diverse factors contributing to the delayed healing of diabetic wounds may be associated with impaired autophagy. Impaired autophagy leads to endothelial and fibroblast dysfunction and impedes macrophage phenotypic transformation. This disruption hinders angiogenesis and extracellular matrix deposition, ultimately culminating in delayed wound healing. Therefore, biomaterials possessing autophagy regulatory functions hold significant potential for clinical applications in enhancing the healing of diabetic wounds. A hybrid multifunctional hydrogel (GelMa@SIS-Qu) has been developed, comprising methacrylamide gelatin (GelMa), a small intestine submucosal acellular matrix (SIS), and quercetin nanoparticles, which demonstrates the capability to promote autophagy. The promotion of autophagy not only reduces ROS levels in endothelial cells and enhances their antioxidant activity but also mitigates ROS-induced endothelial cell dysfunction and apoptosis, thereby promoting angiogenesis. Furthermore, the promotion of autophagy facilitates the phenotypic transformation of macrophages from the M1 phenotype to the M2 phenotype. This study investigates the distinctive mechanisms of the GelMa@SIS-Qu hydrogel and proposes a promising therapeutic strategy for treating diabetes-related wounds.

Vascularization is a critical component of tissue engineering research and is essential for enhancing the success rate of tissue construction and function. Over the past decade, researchers have explored various methods to construct in vitro vascular networks, including 3D printing, cell sphere technology, and microfluidics. Microfluidic technology has garnered significant attention due to its notable advantages in precision, controllability, flexibility, and applicability. It can be primarily classified into two modes: (i) the pre-designed mode, which involves creating vascular networks by pre-designing vascular channels and seeding endothelial cells, encompassing microfluidic chips and microfluidic spinning technologies; and (ii) the self-assembly mode, where cell spheres are fabricated using microfluidic technology and subsequently self-assemble into vascular networks. In this review, we first provide a brief overview of the normal physiological and pathological characteristics of vascular networks, followed by a discussion of the factors to be considered in designing in vitro vascular networks, and conclude with an examination of the classification of technologies for the preparation of microfluidic vascular networks and recent advancements. It is anticipated that in vitro vascular network models will soon be successfully applied in regenerative medicine and drug development.

In Brief: Formation and function of the corpus luteum strongly rely on active angiogenesis. This study demonstrates the role of the hypoxia-inducible factor (HIF) in luteinization with no effect on fertility., Abstract: HIFs are transcription factors responsible for sensing low oxygen levels and, in response, inducing the transcription of numerous genes. One of the main processes stimulated by HIFs is the formation of new vessels to increase oxygen supply to the tissue. Formation of the corpus luteum strongly depends on the vasculature, and active angiogenesis occurs during luteinization. In this study, we aimed to analyze the role of HIF in the early formation of corpus luteum and its function, and in female fertility. To this aim, we superovulated mice using equine chorionic gonadotropin and human chorionic gonadotropin (hCG) and administered the HIF inhibitor acriflavine (ACF) to the mice 3 h before hCG. We found a decrease in ovarian HIF1A and VEGFA and in the vascular area in the animals treated with ACF. Moreover, we observed an increase in aberrant structures in the ovaries and in luteal cell apoptosis. Serum progesterone levels were decreased together with ovarian STAR expression. However, the animals treated with ACF during the early formation of the corpus luteum were completely fertile and no alterations were observed when the treated females were mated with fertile males. These results collectively suggest that HIF regulates gonadotropin-induced corpus luteum formation by acting on luteal blood vessel formation, luteal cell survival and progesterone synthesis. However, adequate HIF activity may not be essential to achieve and maintain pregnancy. These findings are significant to better understand the complex mechanisms of corpus luteum formation and identify potential abnormalities to allow better knowledge of ovarian physiology and pathologies in which this factor could be involved.

Contemporary therapies following heart failure center on regenerative approaches to account for the loss of cardiomyocytes and limited regenerative capacity of the adult heart. While the delivery of cardiac progenitor cells has been shown to improve cardiac function and repair following injury, recent evidence has suggested that their paracrine effects (or secretome) provides a significant contribution towards modulating regeneration, rather than the progenitor cells intrinsically. The direct delivery of secretory biomolecules, however, remains a challenge due to their lack of stability and tissue retention, limiting their prolonged therapeutic efficacy. We hypothesized that polyurethane-based nanoparticles with heteropolar-hydrophobic-ionic chemistry (DPHI-NPs) could enable the delivery of a subset of pro-regenerative cardiac progenitor cell proteins [bone morphogenetic protein-4 (BMP-4) and angiotensin 1-7 (Ang1-7)] to promote biological pathways conducive to repair processes such as antisenescence (through the quantification of β-galactosidase and interleukin-6) and vasculogenesis (through the formation of endothelial tubes), demonstrated in vitro with human cardiac fibroblasts (hCFs) and human microvascular endothelial cells (hMECs), respectively. DPHI-NPs with a diameter of 190 ± 2 nm (polydispersity index < 0.2) and a zeta potential of -40 ± 1 mV were generated using an emulsion inversion technique and loaded with both therapeutic proteins (BMP-4 and Ang1-7) by optimizing surface charge, loading solution concentration, coating duration, and coating efficiency. Senescence-induced hCFs treated with functionalized DPHI-NPs were found to exhibit a significant reduction in expressed β-galactosidase and IL-6 ( p < 0.05). Additionally, hMECs treated with NP BMP-4 were found to display enhanced vasculogenesis compared to control culture conditions alone ( p < 0.05). The development of a DPHI-NP vector for the delivery of pro-regenerative secretome biomolecules may present an effective translatable strategy to improve their therapeutic efficacy with respect to cell function.

Therapeutic angiogenesis has garnered significant attention as a potential treatment strategy for lower limb ischemic diseases. Although hepatocyte growth factor (HGF) has been identified as a key promoter of therapeutic angiogenesis, its clinical application is limited due to its short half-life. In this study, we successfully developed and characterized platelet membrane-coated HGF-poly(lactic- co -glycolic acid) (PLGA) nanoparticles (NPs). These nanoparticles demonstrated enhanced capabilities to promote endothelial cell (EC) proliferation, migration, and tube formation in vitro. Additionally, their efficacy in improving tissue perfusion and promoting angiogenesis was confirmed in a hindlimb ischemia rat model. Our findings suggest that platelet membrane-coated HGF-PLGA-NPs could serve as a promising therapeutic approach for enhancing angiogenesis and restoring tissue perfusion in ischemic conditions.

Background: Chronic Limb-Threatening Ischemia (CLTI) represents the most advanced stage of Peripheral Artery Disease (PAD) and is associated with dire prognosis, characterized by a substantial risk of limb amputation and diminished life expectancy. Despite significant advancements in therapeutic interventions, the underlying mechanisms precipitating the progression of PAD to CLTI remain elusive., Methods: Considering diabetes is one of the main risk factors contributing to PAD exacerbation into CLTI, we compared hind limb ischemia recovery in HFD STZ vs. non-HFD STZ mice to identify new mechanisms responsible for the exacerbation of PAD., Results: We used three different mouse models of diabetes and found that blood flow recovery in HFD STZ mice is altered only from day 14 post-surgery. Consistent with this kinetics, we found that angiogenesis and myogenesis which typically occur between day five and day 14 post-surgery are not impaired in mice in which diabetes was induced by a high fat diet and streptozotocin injections (HFD STZ mice). On the contrary, we found that capillary functionality e.i. acquisition of functional intercellular junctions and immune quiescence is impaired in HFD + STZ mice. Notably, 28 days after hind limb ischemia surgery, HFD + STZ mice display significantly increased capillary permeability to IgG and significantly increased levels of ICAM1. This was associated with an increased macrophage infiltration and an impaired myocyte differentiation. Importantly, we used ICAM1-blocking antibodies to demonstrate that increased ICAM1 expression in HFD + STZ mice decreases white blood cell circulation velocity within the microcirculation, which impairs its perfusion. Notably anti-ICAM1 therapy did diminish macrophage infiltration and oxidative stress but not myopathy suggesting that myopathy characterized by small myocytes expressing higher level of MYH2 could be responsible for microangiopathy., Conclusion: ICAM1 expression by the microvasculature impairs ischemic muscle reperfusion in HFD + STZ mice. Importantly, the increase in blood flow between day 14 and day 90 post-HLI surgery is not associated with an increased capillary density but with an improved functionality of capillaries., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Background: Nonunion following a long bone fracture has gained a lot of attention due to the dreadful impact on the life quality of tremendous patients. Recent data have demonstrated the important involvement of angiogenesis in improving fracture healing. Tetramethylpyrazine (TMP) is an active component of Chinese herbal medicine with various biological activities including pro-angiogenesis property. However, the activity and mechanism of action of TMP in osteo-angiogenesis during bone fracture repair bone fracture healing remain unknown. In this study, TMP was tested for its specific activities in rat aortic endothelial cells (RAECs) and fractured rat model., Methods: The effect of TMP on angiogenesis and migration in RAECs was detected by conducting matrigel tubulogenesis assay and transwell assay. Histopathological changes were observed in the rats from each group using H&E staining. The levels of inflammation and coagulation markers in rats were evaluated by ELISA. The expression of osteogenesis-related genes in rats was assessed by RT-qPCR and western blotting., Results: TMP promoted angiogenesis processes and migratory ability in RAECs. TMP improved histopathological changes in fractured rat model. The concentration of inflammatory markers (IL-2, IL-6, IL-1beta) in the serum of fractured rats were suppressed by TMP treatment. TMP also had the potential to inhibit blood coagulation in rat tibia fracture model. In addition, the expression and protein levels of osteogenesis-related markers (ALP, Runx2, and OPN-1) were elevated by TMP in the tissues from the fractured rats. In mechanism, TMP significantly promoted the activation of VEGF/FLK1 pathway in vitro and in vivo., Conclusion: TMP accelerated the repair of bone fracture by promoting angiogenesis and osteogenesis., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Random skin flap transplantation is critical in wound repair, organ reconstruction and cosmetic surgery, yet skin flap necrosis remains a common and challenging issue. Quercetin, a flavonoid abundant in various plants, exhibits anti-inflammatory, antioxidant, and other beneficial pharmacological effects. Recent studies suggest quercetin can improve random skin flap survival by modulating inflammation, reducing oxidative stress, and promoting angiogenesis. This review evaluates quercetin's potential mechanisms and efficacy, proposing a foundation for its clinical use in preventing ischemic necrosis and enhancing flap viability., Competing Interests: Declarations. Ethical approval: Not required. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Affected by persistent hyperglycemia, diabetic neuropathy, and vasculopathy hinder the progression of wound healing by exacerbating susceptibility to recurrent bacterial infection and impairing vascularization. In order to cater to the requirements of diabetic chronic wound healing at various stages, we designed an antibacterial and pro-angiogenic wound dressing with localized glucose-lowering capacity. In this study, we constructed a copper-based metal-organic framework (MOF) nanozyme and loaded with glucose oxidase (GOX) to prepare Cu-MOF/GOX, which was subsequently integrated with CS-Arg (chitosan modified by L-Arginine) and Pluronic (F127) to fabricate multifunctional Cu-MOF/GOX-Gel thermosensitive hydrogel. The GOX generated H 2 O 2 (hydrogen peroxide) and gluconic acid by consuming high blood glucose at the wound site, thus initiating an efficient antibacterial self-cascade catalytic in the initial stages of wound healing. With the further catalysis of in situ generated H 2 O 2 , NO (nitric oxide) was gradually released from the hydrogel, facilitating angiogenesis and accumulation of collagen, thereby expediting subsequent phases of wound healing. Overall, the Cu-MOF/GOX-Gel exhibits a comprehensive ability to locally regulate blood glucose levels, while also synergistically promoting antibacterial activity and angiogenesis, that effectively chronic diabetic wounds healing., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Regeneration of functional bone tissue relies heavily on achieving adequate vascularization in engineered bone constructs following implantation. This process requires the close integration of osteogenesis and angiogenesis. Cell-free fat extract (CEFFE or FE), a recently emerging acellular fat extract containing abundant growth factors, holds significant potential for regulating osteo-angiogenic coupling and promoting regeneration of vascularized bone tissue. However, its specific role in modulating the coupling between angiogenesis and osteogenesis remains unclear. Our previous research demonstrated that FE-decorated electrospun fibers of polycaprolactone/gelatin (named FE-PDA@PCL/GT) exhibited pro-vasculogenic capabilities both in vitro and in vivo (D. Li, Q. Li, T. Xu, X. Guo, H. Tang, W. Wang, W. Zhang and Y. Zhang, Pro-vasculogenic fibers by PDA-mediated surface functionalization using cell-free fat extract (CEFFE), Biomacromolecules 2024, 25 , 1550-1562). Herein, we firstly demonstrated that the FE-PDA@PCL/GT fibers also significantly stimulated osteogenesis in a mouse calvaria osteoblast-like cell line MC3T3-E1 cells, as evidenced by the increased production of alkaline phosphatase (ALP), mineral deposits, and collagen I, as well as the upregulated expression of osteogenic marker genes in the osteoblasts. Using a transwell co-culture system, we further demonstrated that the release of FE from the FE-PDA@PCL/GT fibers not only promoted osteogenesis and angiogenesis but also markedly enhanced the paracrine functions and reciprocal communications between endothelial cells and osteoblasts. This dynamic interaction played a key role in the observed enhancement of osteo-angiogenic coupling. With the confirmed pro-osteogenic and pro-angiogenic properties of FE-PDA@PCL/GT, it is envisaged that these newly engineered bioactive fibers can be used to develop highly biomimicking bone constructs. These constructs are designed to promote native-like cell-scaffold and cell-cell interactions, which are essential for the effective regeneration of defected bone tissue with adequate vasculature.

Flaps are widely used in surgical wound repair, yet distal necrosis poses a significant postoperative challenge, stemming from potential factors such as inadequate blood perfusion, inflammation, ischemia/reperfusion (I/R) injury, mitochondrial impairment, and subsequent ferroptosis. Empagliflozin (EMPA), a sodium-glucose cotransporter 2 inhibitor, has pharmacological activities that promote angiogenesis, mitophagy, and inhibit inflammation, I/R injury, and ferroptosis. However, it is unclear whether EMPA can enhance flap survival. Here, we established a modified McFarlane flap model and applied EMPA to demonstrate its mechanism of action. 24 rats were evenly divided into four groups: the control, low-dose EMPA (10 mg/kg), high-dose EMPA (30 mg/kg), and inhibitor groups. Molecular biology experiments demonstrated that EMPA promoted the expression of angiogenesis-related factors vascular endothelial growth factor (VEGF) and CD34. Additionally, it also increased superoxide dismutase (SOD) activity and reduced malondialdehyde (MDA) levels, thus suppressing oxidative stress. EMPA further alleviated inflammation by downregulating the expression of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). In vitro experiments showed that EMPA promoted the proliferation of human umbilical vein endothelial cells (HUVECs) and reduce their reactive oxygen species (ROS) production. Further investigation demonstrated that EMPA improves flap prognosis by inducing the expression of the adenosine monophosphate-activated protein kinase (AMPK) signaling pathway, further promoting mitophagy and inhibiting ferroptosis. These effects collectively contributed to the survival of the skin flap. Overall, our research elucidates the protective effects of EMPA on flap survival and its specific mechanisms, offering new insights into solving post-transplant flap necrosis., Competing Interests: Declaration of competing interest All authors declare no potential conflicts of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Full-thickness skin grafts often face challenges related to inefficient vascularization in clinical settings. Senescent cells, known for secreting various growth factors, have demonstrated excellent effects on angiogenesis. In this study, we induced senescence in a subset of fibroblasts in the donor dermis by co-administering trametinib and palbociclib before harvesting the skin grafts for transplantation. Grafts containing these senescent fibroblasts showed significant promotion of vascularization when surgically transplanted into recipient animals. This approach resulted in a 100% survival rate of the transplanted skin. Additionally, the senescent fibroblasts optimized wound healing and matrix remodeling, subsequently reducing inflammation and scar hyperplasia. Importantly, these senescent fibroblasts disappeared 14 days post-grafting, preventing excessive accumulation of senescent cells. Overall, our study indicates that inducing senescence in the donor dermis prior to transplantation is an effective strategy to enhance vascularization and increase the success rate of skin grafting., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Effective vascularization is crucial for the success of tissue engineering and is influenced by numerous factors. The present work focuses on investigating the effect of a substance, cyanobacteria-loaded oxygen-releasing hydrogel, on vascularization and verifying the effect of photosynthetic-oxygen-releasing biomaterials containing a cyanobacteria hydrogel on angiogenesis, using the chick chorioallantoic membrane (CAM) as a model system. On the eighth day of embryonic development, cyanobacterial microspheres were placed on the CAM and maintained in a light incubator under appropriate growth and photosynthesis conditions. The effect of cyanobacterial microspheres on vascularization was evaluated from the eighth day of embryonic development. The carrier material used to prepare the microspheres was a calcium alginate hydrogel, which is biocompatible for maintaining embryonic vitality. The article studied the preparation method, the optimal process, and the specific effects of in vivo co-culture on CAM vascularization and development. The data indicate that our prepared photosynthetic oxygen-releasing blue-green algal microspheres have the potential for symbiosis with tissues by supplying oxygen to tissues and inducing vascular growth through photosynthetic oxygen release. This research opens new avenues for applying cyanobacterial microspheres, a novel biological oxygen-releasing material, in regenerative medicine.

The cranial mesenchyme, originating from both neural crest and mesoderm, imparts remarkable regional specificity and complexity to postnatal calvarial tissue. While the distinct embryonic origins of the superior and dura periosteum of the cranial parietal bone have been described, the extent of their respective contributions to bone and vessel formation during adult bone defect repair remains superficially explored. Utilizing transgenic mouse models in conjunction with high-resolution multiphoton laser scanning microscopy (MPLSM), we have separately evaluated bone and vessel formation in the superior and dura periosteum before and after injury, as well as following intermittent treatment of recombinant peptide of human parathyroid hormone (rhPTH), Teriparatide. Our results show that new bone formation along the dura surface is three times greater than that along the superior periosteal surface following injury, regardless of Teriparatide treatment. Targeted deletion of PTH receptor PTH1R via SMA-CreER and Col 1a (2.3)-CreER results in selective reduction of bone formation, suggesting different progenitor cell pools in the adult superior and dura periosteum. Consistently, analyses of microvasculature show higher vessel density and better organized arterial-venous vessel network associated with a 10-fold more osteoblast clusters at dura periosteum as compared to superior periosteum. Intermittent rhPTH treatment further enhances the arterial vessel ratio at dura periosteum and type H vessel formation in cortical bone marrow space. Taken together, our study demonstrates a site-dependent coordinated osteogenic and angiogenic response, which is determined by regional osteogenic progenitor pool as well as the coupling blood vessel network at the site of cranial defect repair., Competing Interests: Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Chronic diabetic wounds seriously threaten the health and life of human beings, however, it is challenging to develop pluripotent dressings that comprehensively remodel inflammation microenvironment, neovascularization and reepithelization to achieve high performance healing in diabetic wounds. Herein we construct a bioinspired polysaccharide coordinated hydrogel composed of bisphosphate-modified β-glucan (BG) with bioactive metal ions of Zn 2+ and Mg 2+ , in which multiple chelation enables fast gelation, self-healing, and dynamically sealing wounds. In vitro Mg 2+ release from BGM or BGMZ could promote intracellular uptake of Zn 2+ through upregulating Zn 2+ -related transporter protein ZIP6 while intracellular Mg 2+ remained relatively stable via downregulating the Mg 2+ transporter protein of MagT1. The screened lead hydrogel BGMZ could substantially polarize proinflammatory M1 to prohealing M2 phenotypes by the main BG-downregulating NF-kB signaling pathway, and both Mg 2+ and Zn 2+ release from BGMZ synergistically promoted proliferation and angiogenesis by upregulating PI3K/Akt signaling pathway, facilitating the reepithelization and tissue remodeling. Remarkably, single BGMZ treatment performed full-thickness wound closure, fast granulation and dermis regeneration, optimal neovascularization and reepithelization, high levels of overall collagen and fibrous collagen-I, and dense hair follicles, thus achieving high performance prohealing in diabetic wounds. Consequently, this study opens a new avenue to design pluripotent polysaccharide hydrogel dressing for structures and functions remodeling of chronic and diabetic wounds., Competing Interests: Declaration of competing interest These authors declare no competing financial interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Despite their recognized potential for ischemic tissue repair, the clinical use of human mesenchymal stromal cells (hMSC) is limited by the poor viability of cells after injection and the variability of their paracrine function. In this study, we show how the choice of biomaterial scaffolds and the addition of cell preconditioning treatment can address these limitations and establish a proof-of-concept for cryopreservable hMSC-loaded microbeads. Injectable microbeads in chitosan, chitosan-gelatin, and alginate were produced using stirred emulsification to obtain a similar volume moment mean diameter (D[4,3] ∼ 500 µm). Cell viability was determined through live/dead assays, and vascular endothelial growth factor (VEGF) release was measured by ELISA. Proangiogenic function was studied by measuring the wound closure velocity of human umbilical vein endothelial cells (HUVEC) co-cultured with MSC-loaded microbeads. The effect of freeze-thawing on microbeads morphology, porosity, injectability and encapsulated MSC was also studied. hMSC-loaded chitosan-based microbeads were found to release 11-fold more VEGF than alginate microbeads ( p < 0.0001) and chitosan-gelatin was chosen for further studies because it presented the best cell viability. Preconditioning with celastrol significantly enhanced the viability (1.12-fold) and VEGF release (1.40-fold) of MSC-loaded in chitosan-gelatin microbeads, as well as their proangiogenic paracrine function (1.2-fold; p < 0.05). In addition, preconditioning significantly enhanced the viability of hMSC after 1 and 3 d in low-serum medium after cryopreservation ( p < 0.05). Cryopreserved hMSC-loaded microbeads maintained their mechanical properties, were easily injectable through a 23G needle, and kept their paracrine function, enhancing the proliferation and migration of scratched HUVEC. This study shows the advantage of chitosan as a scaffold material and concludes that chitosan-gelatin microbeads with celastrol-preconditioned cells form a promising off-the-shelf, cryopreservable allogenic MSC product. In vivo testing is required to confirm their potential in treating ischemic diseases or other clinical applications., (Creative Commons Attribution license.)

Introduction: FTY720 bioactive lipid has proliferative, osteoinductive, chemo attractive, and angiogenic properties, being thus a potential exogenous administered agent for promotion of bone regeneration. Herein we developed FTY720-loaded liposomes as a potential delivery system that could retain and prolong the bioactivity of the bioactive lipid and at the same time reduce its cytotoxicity (at high doses)., Methods: FTY720 liposomes were prepared by thin-lipid hydration and microfluidic flow focusing, and evaluated for their ability to induce proliferation, osteoinduction, and chemoattraction in three cell types: MC3T3-E1 pre-osteoblast cells, L929 fibroblast cells, and ATDC5 chondrogenic cells. The angiogenic activity of free and liposomal FTY720 was investigated using a chick chorioallantoic membrane assay. NBD-FTY720 cellular uptake was quantitated using flow cytometry and morphologically assessed by confocal microscopy. Implicated cellular signaling mechanisms were investigated by quantifying phosphorylated MAPK and CREB proteins., Results: FTY720 liposomes (~80-110 nm) with low polydispersity and ~100% loading were prepared using both methods. FTY720 demonstrated the ability to increase cell proliferation at 10-300nM doses but was cytotoxic at doses>400nM while the corresponding liposomal-FTY720 doses were non-cytotoxic, proving its reduced toxicity. In several cases (cells and doses), FTY720 liposomes demonstrated increased osteogenic differentiation of cells, proliferation, and migration compared to free FTY720, whereas both FTY720 forms demonstrated substantial angiogenic activity. Liposomal FTY720 cellular uptake was substantially higher than that of free FTY720 in some cases, a fact that may be connected to its higher bioactivity. Increased phosphorylated MAPK and CREB protein concentrations provided information about the potential cellular signaling mechanisms involved in FTY720-induced osteogenesis., Discussion: The current results confirm the high potential of FTY720 bioactive lipid, especially in its liposomal form, that demonstrated substantial reduction of cytotoxicity and prolonged preservation of the lipids bioactivity (compared to the free lipid), for accelerated treatment of bone defects. Interestingly, the current studies prove the potential of FTY720, especially in its liposomal form, to promote reprogramming of L929 fibroblasts into osteoblasts, a novel finding deserving future exploitation., Competing Interests: The authors report no conflicts of interest in this work., (© 2025 Mouzoura et al.)

Myocardial infarction (MI) remains a leading cause of mortality worldwide, posing a significant challenge to healthcare systems. The limited regenerative capacity of cardiac tissue following MI results in chronic cardiac dysfunction, highlighting the urgent need for innovative therapeutic strategies. In this study, we explored the application of a multidimensional nanofibrous hydrogel for myocardial regeneration. We developed a composite hydrogel system by integrating fibrin, polycaprolactone (PCL), and alginate. In this system, fibrin supported cell proliferation and significantly enhanced angiogenesis when combined with human umbilical vein endothelial cells (HUVECs). PCL contributed to the alignment of encapsulated cells, improving their organization within the scaffold. Adipose-derived stem cells (ADSCs) were encapsulated within the hydrogel for their versatile regenerative potential, while C2C12 cells were incorporated for their ability to form muscle tissue. Additionally, the inclusion of alginate not only enhanced the mechanical properties of the hydrogel to better match the biomechanical demands of cardiac tissue but also played a critical role in reducing the immune response, thereby improving the system's biocompatibility. This study presents an advanced platform for myocardial regeneration using a nanofibrous hydrogel system designed to meet the dual requirements of mechanical robustness and cellular compatibility essential for cardiac tissue engineering. The triculture system, consisting of ADSCs, C2C12 cells, and HUVECs, harnesses the regenerative capabilities of each cell type, promoting both angiogenesis and tissue regeneration. This comprehensive approach addresses the immediate needs for cellular survival and integration while effectively overcoming long-term mechanical and immunological challenges., (© 2025 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)

Angiogenesis describes the sprouting of blood vessels from existing vasculatures and it plays a pivotal role in disease progress such as diabetes, age-related macular degeneration and cancer. However, the most widely used anti-angiogenic agents targeting vascular endothelial growth factor (VEGF) pathway still lacked of specificity and therapeutic efficacy. To establish a method suitable for high-throughput drug screening and faithfully recapitulate the feature of in vivo angiogenesis, we generated a PECAM1-mRuby3-secNluc; ACTA2-EGFP dual reporter human pluripotent stem cell (hPSC) line and utilizing the cell line to establish a visualized and quantifiable in vitro angiogenesis model with stem cell-derived vascular organoid. Using this method, we evaluated the anti-angiogenic effect of VEGFR inhibitor and efficiently identified several potential candidates of pro- and anti-angiogenic therapy via bioluminescence-based quantification. Overall, our study provides a valuable platform for in vitro drug screenings., Competing Interests: Declarations. Competing interests: The authors declare no competing interests. Supplementary Information: The online version contains supplementary material available., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Chondroitin sulfate (CS), a class of glycosaminoglycans covalently attached to proteins to form proteoglycans, is widely distributed in the extracellular matrix and cell surface of animal tissues. In our previous study, CS was used as a template for the synthesis of seleno-chondroitin sulfate (SeCS) through the redox reaction of ascorbic acid (Vc) and sodium selenite (Na 2 SeO 3 ) and we found that SeCS could inhibit tumor cell proliferation and invasion. However, its effect on angiogenesis and its underlying mechanism are unknown. In this study, we analyzed the effect of SeCS on tube formation in vitro, based on the inhibition of tube formation and migration of human umbilical vein endothelial cells (HUVECs), and evaluated the in vivo angiogenic effect of SeCS using the chick embryo chorioallantoic membrane (CAM) assay. The results showed that SeCS significantly inhibited the angiogenesis of chicken embryo urothelium. Further mechanism analysis showed that SeCS had a strong inhibitory effect on VEGFR2 expression and its downstream PI3K/Akt signaling pathway, which contributed to its anti-angiogenic effects. In summary, SeCS showed good anti-angiogenic effects in an HUVEC cell model and a CAM model, suggesting that it may be a potential angiogenesis inhibitor.

Ovarian function declines significantly as females enter middle-age, but the mechanisms underlying this decline remain unclear. Here, we utilize whole-organ imaging to observe a notable decrease in ovarian blood vessel (oBV) density and angiogenesis intensity of middle-aged mice. This leads to a diminished blood supply to the ovaries, resulting in inadequate development and maturation of ovarian follicles. Utilizing genetic-modified mouse models, we demonstrate that granulosa cell secreted VEGFA governs ovarian angiogenesis, but the physiological decline in oBV is not attributed to VEGFA insufficiency. Instead, through single-cell sequencing, we identify the aging of the ovarian vascular endothelium as the primary factor contributing to oBV decline. Consequently, the administration of salidroside, a natural compound that is functional to reverse oBV aging and promote ovarian angiogenesis, significantly enhances ovarian blood supply and improve fertility in older females. Our findings highlight that enhancing oBV function is a promising strategy to boost fertility in females., Competing Interests: Competing interests: The author declares no competing interests., (© 2024. The Author(s).)

In this study, a new hybrid nanoparticle composed of magnesium hydroxide and copper oxide (Mg(OH) 2 /CuO) with an optimized ratio of magnesium (Mg) to copper (Cu) was designed and incorporated into a 3D-printed scaffold made of polycaprolactone (PCL) and gelatin. These hybrid nanostructures (MCNs) were prepared using a green, solvent-free method. Their topography, surface morphology, and structural properties were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The fabricated 3D-printed PCL/Gelatin/MCN scaffolds were investigated in vitro and in vivo. Cell viability tests on murine calvarial preosteoblasts (MC3T3-E1) and human umbilical vein endothelial cells (HUVECs) demonstrated that the scaffolds could induce proper cell proliferation. Additionally, the angiogenic and osteogenic properties of the constructs were evaluated using alkaline phosphatase (ALP) activity, osteogenesis-related, and angiogenesis-related gene expression tests. The in vivo study was conducted using a rat calvarial defect model, which confirmed the superior angiogenic and osteogenic properties of the PCL/gelatin/MCN scaffolds compared to PCL/Gelatin and PCL/Gelatin/Mg(OH) 2 scaffolds. Overall, the PCL/Gelatin/MCN scaffolds showed promising potential for bone regeneration, particularly for critical-sized defects where proper angiogenesis is essential for tissue reconstruction., (© 2025 Wiley Periodicals LLC.)

Spinal cord injury (SCI) is a common nerve injury caused by external force, resulting in sensory and motor impairments. Previous studies demonstrated that inhibiting the neuroinflammation promoted SCI repair. However, these approaches are low efficient, and lack targeting specificity, and even require repeated and high doses of systemic administration. To address such issues, in the present study, chitosan-modified hydrogel microspheres encapsulating with zinc-doped bioactive glasses (CS-MG@Zn/BGs) is constructed for targeted repair of SCI. In vitro, the CS-MG@Zn/BGs effectively inhibited the acute inflammatory response initiated by microglia and promoted angiogenic activities. In vivo, CS-MG@Zn/BGs targeted the injured site, and attenuated neuroinflammation by inhibiting microglia infiltration and modulating microglia polarization toward M2 type. Furthermore, it facilitated vascular reconstruction, neuronal differentiation, axonal regeneration and remyelination at the injured site, and thereby promoted motor function recovery of SCI mice. The in vitro and in vivo results implied that CS-MG@Zn/BGs may be a promising alternative for the rehabilitation of SCI., (© 2024 Wiley‐VCH GmbH.)

Aging impairs bone marrow mesenchymal stem cell (BMSC) functions as well as associated angiogenesis which is critical for bone regeneration and repair. Hence, repairing bone defects in elderly patients poses a formidable challenge in regenerative medicine. Here, the engineered dental pulp stem cell-derived exosomes loaded with the natural derivative of adenosine Cordycepin (CY@D-exos) are fabricated by means of the intermittent ultrasonic shock, which dually rejuvenates both senescent BMSCs and endothelial cells and significantly improve bone regeneration and repair in aged animals. CY@D-exos can efficiently overcome the senescence of aged BMSCs and enhance their osteogenic differentiation by activating NRF2 signaling and maintaining heterochromatin stability. Importantly, CY@D-exos also potently overcomes the senescence of vascular endothelial cells and promotes angiogenesis. In vivo injectable gelatin methacryloyl (GelMA) hydrogels with sustained release of CY@D-exos can accelerate bone injury repair and promote new blood vessel formation in aged animals. Taken together, these results thus demonstrate that cordycepin-loaded dental pulp stem cell-derived exosomes display considerable potential to be developed as a next-generation therapeutic agent for promoting aged bone regeneration and repair., (© 2024 Wiley‐VCH GmbH.)

Background: Angiogenesis of brain microvascular endothelial cells (BMECs) after cerebral ischemia was conducive to improving the blood supply of ischemia tissues, which was upregulated by glycolysis. Hydroxysafflor Yellow A (HSYA) mends damaged tissues through increasing angiogenesis., Methods: HSYA treated proliferation, migration and angiogenesis of BMECs in vitro in vitro during OGD/R. HSYA regulated the key enzymes of glycolysis, such as hexokinase 2 (HK2) and 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3), glucose uptake and products (pyruvate, ATP and lactate) were detected by western blot and kits, respectively. Scratch wound assay, transwell, tube formation and spheroid sprouting were used to explore the pathway that HSYA recovered migration and angiogenesis of BMECs. We evaluated the potential target of HSYA promoting glycolysis via molecular docking, drug affinity responsive target stability (DARTS) and cellular thermal shift assay (CETSA)., Results: HSYA promoted the proliferation, migration, tube formation and spheroid sprouting of BMECs during OGD/R, and stimulated the expression of tip phenotype marker protein (CD34), and the receptor (Notch-1) that regulated the differentiation of endothelial cells into tip/stalk phenotype. In glycolysis, PFKFB3 expression was upregulated by HSYA; HSYA also improved ATP and pyruvate levels, as well as lactate release after OGD/R. Finally, upregulating VEGFA and p-VEGFR2 of HSYA was weakened because of suppressing glycolysis; the HSYA's improvement of BMECs migration and angiogenesis was attenuated under the inhibition of glycolysis, which confirmed that HSYA were upregulating angiogenesis and expression of VEGFA/VEGFR2 by glycolysis pathway. The result about molecular docking, DARTS and CETSA suggested that PFKFB3 was the possible target of HSYA., Conclusion: HSYA promotes angiogenesis of BMECs in vitro through the glycolysis mediated VEGFA/VEGFR2 pathway, and PFKFB3 is the potential target of HSYA to heighten glycolysis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Dynamic growth factor presentation influences how individual endothelial cells assemble into complex vascular networks. Here, programmable bioinks are developed that facilitate dynamic vascular endothelial growth factor (VEGF) presentation to guide vascular morphogenesis within 3D-bioprinted constructs. Aptamer's high affinity is leveraged for rapid VEGF sequestration in spatially confined regions and utilized aptamer-complementary sequence (CS) hybridization to tune VEGF release kinetics temporally, days after bioprinting. It is shown that spatial resolution of programmable bioink, combined with CS-triggered VEGF release, significantly influences the alignment, organization, and morphogenesis of microvascular networks in bioprinted constructs. The presence of aptamer-tethered VEGF and the generation of instantaneous VEGF gradients upon CS-triggering restricted hierarchical network formation to the printed aptamer regions at all spatial resolutions. Network properties improved as the spatial resolution decreased, with low-resolution designs yielding the highest network properties. Specifically, CS-treated low-resolution designs exhibited significant vascular network remodeling, with an increase in vessel density(1.35-fold), branching density(1.54-fold), and average vessel length(2.19-fold) compared to non-treated samples. The results suggest that CS acts as an external trigger capable of inducing time-controlled changes in network organization and alignment on-demand within spatially localized regions of a bioprinted construct. It is envisioned that these programmable bioinks will open new opportunities for bioengineering functional, hierarchically self-organized vascular networks within engineered tissues., (© 2024 The Author(s). Advanced Healthcare Materials published by Wiley‐VCH GmbH.)

Inhibiting bacterial growth and promoting angiogenesis are essential for enhancing wound healing in diabetic patients. Excessive oxidative stress at the wound site can also lead to an accumulation of reactive oxygen species. To address these challenges, a smart thermosensitive hydrogel loaded with therapeutic agents was developed. This formulation features self-assembled nanoparticles named CIZ, consisting of chlorogenic acid (CA), indocyanine green (ICG), and zinc ions (Zn 2+ ). These nanoparticles are loaded into a chitosan-β-glycerophosphate hydrogel, named CIZ@G, which enables rapid gel formation under photothermal effects. The hydrogel demonstrates good biocompatibility and effectively releases drugs into diabetic foot ulcers (DFU) wound. Benefiting from the dual actions of CA and zinc ions, the hydrogel exhibits potent antioxidative and anti-inflammatory effects, enhances the expression of vascular endothelial growth factor (VEGF) and Platelet endothelial cell adhesion molecule-1 (CD31), and promotes angiogenesis. Both in vitro and in vivo experiments confirm that CIZ@G can effectively inhibit the growth of Staphylococcus aureus post-laser irradiation and accelerate wound remodeling within 14 days. This approach offers a new strategy for the treatment of diabetic foot ulcers (DFU), potentially transforming patient care in this challenging clinical area., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

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 SIGNIFICANCE: 1) 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., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

One of the foremost targets in the advancement of biomaterials to engineer vascularized tissues is not only to replicate the composition of the intended tissue but also to create thicker structures incorporating a vascular network for adequate nutrients and oxygen supply. For the first time, to the best of current knowledge, a clinically relevant biomaterial is developed, demonstrating that hydrogels made from the human decellularized extracellular matrix can exhibit robust mechanical properties (in the kPa range) and angiogenic capabilities simultaneously. These properties enable the culture and organization of human umbilical vein endothelial cells into tubular structures, maintaining their integrity for 14 days in vitro without the need for additional polymers or angiogenesis-related factors. This is achieved by repurposing the placenta chorionic membrane (CM), a medical waste with an exceptional biochemical composition, into a valuable resource for bioengineering purposes. After decellularization, the CM underwent chemical modification with methacryloyl groups, giving rise to methacrylated CM (CMMA). CMMA preserved key proteins, as well as glycosaminoglycans. The resulting hydrogels rapidly photopolymerize and have enhanced strength and customizable mechanical properties. Furthermore, they demonstrate angio-vasculogenic competence in vitro and in vivo, holding significant promise as a humanized platform for the engineering of vascularized tissues., (© 2024 Wiley‐VCH GmbH.)

Background: Tacrolimus is a cornerstone of immunosuppression in solid organ transplants, but its use is linked with the development of endothelial dysfunction. Pregnant solid organ transplant recipients are four to six times more likely to develop preeclampsia, which is also associated with endothelial dysfunction. Therefore, this in vitro study investigated the acute effects of tacrolimus on the expression of common angiogenic factors related to preeclampsia, and effects on angiogeneis in primary human tissues., Methods: Primary human umbilical vein endothelial cells (HUVECs) were exposed to tacrolimus (0, 5, 20, 50 ng/mL) for 24h alone, or in combination with tumour necrosis factor (TNF, 10 ng/mL) and high dose glucose (25 mM). Cell culture concentrations of sFlt-1, PlGF and activin A were measured. In addition, the effect of tacrolimus on markers of endothelial dysfunction and permeability were assessed, as were the effect of tacrolimus on tube formation. Angiogenic factors and mRNA markers of oxidative stress and inflammation were also assessed in primary placental tissue after an acute 24 h exposure to tacrolimus., Results: Tacrolimus exposure significantly reduced HUVEC secretion of PlGF, increased production of activin A, andreduced tubular structure formation without impacting cell permeability or viability. There was no change in ICAM1 or VCAM1 expression in HUVECs treated with tacrolimus treatment alone, however co-culture with TNF significantly increased expression of ICAM1 and VCAM1. In placental explants tacrolimus did not change angiogenic factor production or markers of inflammation or oxidative stress., Conclusion: An acute tacrolimus exposure reduced PlGF secretion and impaired angiogenesis in primary endothelial cells, without affecting. These findings provide a potential mechanistic basis for tacrolimus to contribute to the endothelial dysfunction contributing to preeclampsia., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Concentration gradients of soluble signaling molecules-morphogens-determine the cellular organization in tissue development. Morphogen-releasing microgels have shown potential to recapitulate this principle in engineered tissue constructs, however, with limited control over the molecular cues in space and time. Inspired by the functionality of sulfated glycosaminoglycans (sGAGs) in morphogen signaling in vivo, a library of sGAG-based microgels is developed and designated as µGel Units to Instruct Development (µGUIDEs). Adjustment of the microgel's sGAG sulfation patterns and concentration enabled the programming of electrostatic affinities that control the release of morphogens. Based on computational analyses of molecular transport processes, µGUIDEs provided unprecedented precision in the spatiotemporal modulation of vascular endothelial growth factor (VEGF) gradients in a microgel-in-gel vasculogenesis model and kidney organoid cultures. The versatile approach offers new options for creating morphogen signaling centers to advance the understanding of tissue and organ development., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)

Background: Promoting the coupling of osteogenesis and angiogenesis is a crucial strategy for the treatment of postmenopausal osteoporosis (PMOP). Estrogen deficiency induces ferroptosis, which is closely associated with the pathophysiology of PMOP. Sarsasapogenin (SAR) is a natural sapogenin with anti-oxidative effects. However, it is unclear whether SAR has a protective role against the impaired osteogenesis and angiogenesis coupling in PMOP. In this study, we evaluated the efficacy of SAR in estrogen deficiency-induced osteoporosis and explored the underlying mechanisms., Methods: Bone marrow mesenchymal stem cells (BMSCs) and human umbilical vein endothelial cells (HUVECs) were utilized to assess the in vitro effects of SAR on the coupling of osteogenesis and angiogenesis. In vivo experiments involved bilateral ovariectomy (OVX)-induced osteoporosis in mice and glutathione peroxidase 4 (GPX4)-knockout (KO) mice. Mice were orally administered SAR (5 or 10 mg/kg/d) for a duration of 12 weeks. The direct target of SAR was investigated through molecular docking, a cellular thermal shift assay, and surface plasmon resonance. Additionally, RNA sequencing was employed to elucidate the underlying mechanisms., Results: SAR treatment improved cell viability and osteogenic differentiation while inhibiting ferroptosis in iron dextran-induced BMSCs. Furthermore, SAR enhanced the production of slit guidance ligand 3 (SLIT3) in these cells, which stimulated angiogenesis by activating its receptor, roundabout human homolog 1 (ROBO1), in HUVECs. An in vitro model of ferroptosis induced by erastin demonstrated that SAR promoted the coupling of osteogenesis and angiogenesis by upregulating the BMSCs-SLIT3/HUVECs-ROBO1 axis. Activation of GPX4 was identified as a contributing factor to the effects of SAR on this coupling. Transfection of GPX4 small interfering RNA (siRNA) in BMSCs negated the impact of SAR on the BMSCs-SLIT3/HUVECs-ROBO1 axis. Additionally, SAR was found to directly interact with GPX4, enhancing protein stability, with an equilibrium dissociation constant of 44.6 μM. Notably, SAR did not increase SLIT3, ROBO1, or indicators of osteogenesis or angiogenesis in GPX4-KO mice., Conclusions: These findings underscore the significance of restoring the GPX4/SLIT3/ROBO1 axis in promoting the coupling of angiogenesis and osteogenesis. SAR mitigates PMOP, in part, by activating the BMSCs-SLIT3/HUVECs-ROBO1 axis, with GPX4 serving as an upstream signaling modulator responsible for SLIT3 production. Our observations provide experimental evidence supporting the clinical application of SAR in the treatment of PMOP., Competing Interests: Declaration of competing interest There are no conflicts of interest., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

Potential therapies for wound management remain one of the most challenging affairs to date. Biopolymer hydrogels possess inherent properties that facilitate the healing of damaged tissue by creating a supportive and hydrated environment. Chitosan/fibroin hydrogels were formulated with poly (vinyl pyrrolidone) and cross-linked using 3-aminopropyl (diethoxy) methylsilane (APDEMS) for the aforementioned function. The hydrogels were characterized through Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy, and their swelling response was observed using a variety of solvents. Additionally, hydrogels were investigated for biomedical applications. As the amount of fibroin added to the hydrogels increased, the swelling ratio decreased. The analysis of chorioallantoic membrane (CAM) assay revealed that higher concentrations of fibroin in the hydrogel were directly correlated with increased angiogenesis. The intragroup comparison showed that the vascular number in the CPF5 group was significantly increased (p ≤ 0.05) compared to other hydrogel groups. The wound healing efficiency of the prepared hydrogels showed that the rate of wound reduction (99.06%) was remarkably (p ≤ 0.05) high in the hydrogel group with a greater fibroin content against control (67.03%). Histological findings of wounded tissues corroborate the abovementioned results, showing dense fibrous connective tissues in the fibroin group compared to the control. The results of this work provide thorough preclinical evidence that chitosan-fibroin biopolymers are involved in enhanced angiogenesis in growing chicks and speed up wound healing in mice without any obvious toxicity., (© 2024 Wiley Periodicals LLC.)

Microporous hydrogels have been widely used for delivering therapeutic cells. However, several critical issues, such as the lack of control over the harsh environment they are subjected to under pathological conditions and rapid egression of cells from the hydrogels, have produced limited therapeutic outcomes. To address these critical challenges, cell-tethering and hypoxic conditioning colloidal hydrogels containing mesenchymal stem cells (MSCs) are introduced to increase the productivity of paracrine factors locally and in a long-term manner. Cell-tethering colloidal hydrogels that are composed of tyramine-conjugated gelatin prevent cells from egressing through on-cell oxidative phenolic crosslinks while providing mechanical stimulation and interconnected microporous networks to allow for host-implant interactions. Oxygenating microparticles encapsulated in tyramine-conjugated colloidal microgels continuously generated oxygen for 2 weeks with rapid diffusion, resulting in maintaining a mild hypoxic condition while MSCs consumed oxygen under severe hypoxia. Synergistically, local retention of MSCs within the mild hypoxic-conditioned and mechanically robust colloidal hydrogels significantly increased the secretion of various angiogenic cytokines and chemokines. The oxygenating colloidal hydrogels induced anti-inflammatory responses, reduced cellular apoptosis, and promoted numerous large blood vessels in vivo. Finally, mice injected with the MSC-tethered oxygenating colloidal hydrogels significantly improved blood flow restoration and muscle regeneration in a hindlimb ischemia (HLI) model., (© 2024 Wiley‐VCH GmbH.)

Failure of orthopedic implants due to localized bacterial infections, inflammation and insufficient blood supply is always problematic. In this study, strontium-doped titanium dioxide nanotubes (STN) were firstly prepared on titanium surface, and then lactoferrin (LF) was loaded into strontium-doped nanotubes (STN) by the phase transition method, eventually the LF/TCEP-STN composite coating was successfully prepared. With the innate antimicrobial properties of LF, LF/TCEP-STN was effected against E. coli and S. aureus. Cellular assays showed that RAW264.7 (immune), HUVEC (angiogenic) and MC3T3-E1 (osteogenic) exhibited good adhesion and proliferative activity on the surface of LF/TCEP-STN. At the molecular level, LF/TCEP-STN modulated RAW264.7 polarization toward M2-type while promoting MC3T3-E1 differentiation toward osteogenesis. Meanwhile LF/TCEP-STN coating effectively promoted angiogenesis. The results of the bone defect model with or without infection demonstrated that the LF/TCEP-STN material had good anti-inflammatory, antibacterial, and vascularization-promoting osteogenesis. In addition, LF/TCEP-STN offered excellent blood compatibility and biosafety. As a multifunctional coating on implant surfaces, the study's results highlighted the viability of LF/TCEP-STN and offered fresh concepts for the clinical design of next-generation artificial bone implants with antibacterial, anti-inflammatory, and osteogenic properties., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Pulpitis is inflammation of the dental pulp, often caused by bacterial infection from untreated cavities, leading to pain. The main challenge in treatment is eliminating infection while preserving tooth vitality. This study aims to address this challenge by developing a hydrogel for convenient insertion into the root canal system, securely attaching to dentin walls. An injectable hydrogel system is developed by chemically cross-linking natural polysaccharide pectin with gelatin (GPG) through reversible Schiff base reaction. The GPG system was then used to encapsulate and release drugs, such as ciprofloxacin (CIP) for infection prevention and deferoxamine (DFO) for promoting blood vessel proliferation and reducing inflammatory reactions. The GPGs absorbed significant amounts of CIP and DFO, enabling sustained release over a nearly ten-day period. When subcutaneously implanted, the GPGs formed stable gel depots, with only 50 % of the gels degrading after 3 weeks, indicating a sustained biodegradation pattern. Additionally, the GPG system demonstrated excellent antibacterial activity against both gram-negative and gram-positive bacteria. Results from in vitro scratch healing tests and in ovo chorioallantoic membrane chick model tests showed promising biocompatibility and promotion of vascular proliferation by the GPG. This study heralds a novel frontier in endodontic therapeutics, poised to potentially enable dental pulp regeneration., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Local implantation or supplementation of magnesium gluconate (MgG) is being investigated as an effective approach to bone repair. Although studies have highlighted the possible mechanisms in Mg ion-stimulated new bone formation, the role of MgG in healing bone defects and the signaling mechanisms are not yet completely understood. In this study, we explored how supplemental MgG has bone-specific beneficial effects by delivering MgG locally and orally in animal models. We fabricated MgG-incorporated (CMC-M) and -free chitosan (CMC) scaffolds with good microstructures and biocompatible properties. Implantation with CMC-M enhanced bone healing in rat model of mandible defects, compared with CMC, by activating Wnt signals and Wnt-related osteogenic and angiogenic molecules. Oral supplementation with MgG also stimulated bone healing in mouse model of femoral defects along with the increases in Wnt3a and angiogenic and osteogenic factors. Supplemental MgG did not alter nature bone accrual and bone marrow (BM) microenvironment in adult mouse model, but enhanced the functioning of BM stromal cells (BMSCs). Furthermore, MgG directly stimulated the induction of Wnt signaling-, angiogenesis-, and osteogenesis-related molecules in cultures of BMSCs, as well as triggered the migration of endothelial cells. These results suggest that supplemental MgG improves bone repair in a way that is synergistically enhanced by Wnt signal-associated angiogenic and osteogenic molecules. Overall, this study indicates that supplemental MgG might ameliorate oxidative damage in the BM, improve the functionality of BM stem cells, and maintain BM-microenvironmental homeostasis., (© 2024 Wiley Periodicals LLC.)

Early healing of bone defects is still a clinical challenge. Many bone-filling materials have been studied, among which photocrosslinked alginate has received significant attention due to its good biocompatibility and morphological plasticity. Although it has been confirmed that photocrosslinked alginate can be used as an extracellular matrix for 3D cell culture, it lacks osteogenesis-related biological functions. This study constructed a copper ions-photo dual-crosslinked alginate hydrogel scaffold by controlling the copper ion concentration. The scaffolds were shaped by photocrosslinking and then endowed with biological functions by copper ions crosslinking. According to in vitro research, the dual-crosslinked hydrogel increased the compressive strength and favored copper dose-dependent osteoblast differentiation and cell surface adherence of rat bone marrow mesenchymal stem cells and the expression of type I collagen (Col1), runt-related transcription factor 2 (Runx2), osteocalcin (OCN), vascular endothelial growth factor (VEGF). In addition, hydrogel scaffolds were implanted into rat skull defects, and more angiogenesis and osteogenesis could be observed in in vivo studies. The above results show that the copper-photo-crosslinked hydrogel scaffold has excellent osseointegration properties and can potentially promote angiogenesis and early healing of bone defects, providing a reference solution for bone tissue engineering materials., (© 2024 Wiley Periodicals LLC.)

Adequate blood supply and thorough innervation are essential to the survival of tissue-engineered bones. Though great progress has been created in the application of bone tissue engineering technology to bone defect repair, many challenges remain, such as insufficient vascularisation and deficient innervation in newly regenerated bone. In the present study, we addressed these challenges by manipulating the bone regeneration microenvironment in terms of vascularisation and innervation. We used a novel injectable thermosensitive liposome-hydrogel composite scaffold as a sustained-release carrier for basic fibroblast growth factor (bFGF, which promotes angiogenesis and neurogenic differentiation) and dexamethasone (Dex, which promotes osteogenic differentiation). In vitro biological assessment demonstrated that the composite scaffold had sufficient cell compatibility; it enhanced the capacity for angiogenesis in human umbilical vein endothelial cells, and the capacity for neurogenic/osteogenic differentiation in human bone marrow mesenchymal stem cells. Moreover, the introduction of bFGF/Dex liposome-hydrogel composite scaffold to bone defect sites significantly improved vascularisation and innervated bone regeneration properties in a rabbit cranial defect model. Based on our findings, the regeneration of sufficiently vascularised and innervated bone tissue through a sustained-release scaffold with excellent injectability and body temperature sensitivity represents a promising tactic towards bone defect repair., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Bothrops asper venom (Bav) contains metalloproteinases that disrupt the microvascular system, impairing muscle tissue regeneration after injury. This study investigated the impact of the cyclooxygenase-2 (COX-2) pathway on vascular injury and revascularization in muscle injuries induced by Bav. Mice were injected with Bav into the gastrocnemius muscle and treated with lumiracoxib, a selective COX-2 inhibitor, 30 min, 2 days, and 6 days post-Bav injection. Muscle tissue was analyzed at 24 h, 7 days, and 21 days post-injection. A decrease in COX-2 expression at 24 h post-Bav injection indicated significant necrosis and tissue loss. Both Bav injection and lumiracoxib treatment influenced the decrease of prostaglandin (PG)D 2 and PGE 2 production. Seven and 21 days post-Bav injections, COX-2 expression increased, along with PGDs levels unaffected by lumiracoxib, indicating that the other isoform COX-1 pathway could contribute to the release of PGs. Bav/lumiracoxib treated animals presented exacerbated limb ischemia, implying that COX-2-derived prostaglandins preserve vessel integrity. CD31, an angiogenesis marker, initially (24 h) decreased post-Bav injection but increased at 7 and 21 days in Bav/lumiracoxib mice, suggesting a down-modulatory role for COX-2-derived prostaglandins in early angiogenesis and tissue regeneration. Vascular endothelial growth factor (VEGF) production rose 7 days post-Bav injection, supporting its role in angiogenesis. Previous treatment with lumiracoxib promoted release of VEGF levels 21 days post-Bav injury showing that the inhibition of COX-2 pathway in the early stage of revascularization stimulates the neovascularization regulated by elevated release of VEGF. Similarly, metalloproteinases (MMPs), such as MMP-9, MMP-10, and MMP-13, crucial for vascular remodeling, were elevated 21 days after Bav/lumiracoxib treatment. In conclusion, the COX-2 pathway is essential to decrease the high grade of ischemia caused by acute injury induced by Bav. However, the decrease of activity in the COX-2 pathway in the first stages of revascularization contributes to the elevated production of key pro-angiogenic mediators that up-regulate the restoration of microvasculature and blood flow in muscle tissue injured by botropic venoms., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Critical-sized orbital bone defects can lead to significant maxillofacial deformities and even eye movement disorders. The challenges associated with these defects, including their complicated structure, inadequate blood supply, and limited availability of progenitor cells that hinder successful repair. To overcome these issues, we developed a novel approach using computer numerical control (CNC) material reduction manufacturing technology to produce a customized polyetheretherketone (PEEK) scaffold that conforms to the specific shape of orbital bone defects. Deferoxamine (DFO) was in situ encapsulated into polydopamine-hybridized zeolitic imidazolate framework-8 (pZIF8-DFO) nanoparticles, which was subsequently adhered to the sulfonated PEEK (sPEEK) scaffold through polydopamine modification. This functionalization enhanced drug loading efficiency and imparted anti-inflammatory properties to the nanoparticle system. Our in vitro findings demonstrated that the sustained release of DFO from the sPEEK/pZIF8-DFO scaffolds extended over 14 days and significantly promoted angiogenesis and progenitor cell recruitment, as evidenced by increased expression of HIF-1α, VEGF, and SDF-1α expression in human umbilical vein endothelial cells (HUVECs). Moreover, sPEEK/pZIF8-DFO scaffolds exhibited superior immunomodulation and osteogenic differentiation capabilities on Raw 264.7 cells and rabbit bone marrow mesenchymal stem cells (rBMSCs), respectively. Most notably, our in vivo rabbit orbital bone defects revealed that sPEEK/pZIF8-DFO scaffolds resulted in a greater volume of new bone formation than on sPEEK and sPEEK/pZIF8 scaffolds, with partial bone connection to the sPEEK/pZIF8-DFO scaffolds. In summary, we develop a novel PEEK scaffold that combines enhanced angiogenesis, stem cell recruitment, immunomodulation, and osteogenic differentiation, showcasing its promising potential for orbital bone reconstruction., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Infected skin wounds represent a class of significant clinical challenges due to their complexity and the risk of delayed healing. Developing an effective wound dressing capable of promoting tissue regeneration while addressing infections is crucial. In this study, we designed a dual peptide-coordinated dynamic hydrogel with both antibacterial and proangiogenic properties, specifically tailored for treating infected skin wounds. The dynamic hydrogel was constructed using gelatin, a natural biomacromolecule with high biocompatibility, as the base material. Two functional peptides, the antibacterial melittin and angiogenic peptide, were incorporated to enhance both infection control and tissue repair. Hydrogelation was achieved through coordination interactions between gold (Au) ions and sulfhydryl groups, endowing the hydrogel with dynamic properties. The excellent biocompatibility, antibacterial efficacy and angiogenic capability of hydrogel allow it to provide structural support for wound healing while promoting cell proliferation and migration. By eradicating bacteria and stimulating new blood vessel formation, it accelerates the healing of infected wounds. Additionally, its injectability and self-healing properties make it suitable for treating irregularly shaped and deep wounds. This dual-functional hydrogel may offer a promising and minimally invasive treatment option for infected skin wounds, combining high biological safety with simplified surgical procedures., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The authors declare no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In the context of severe burn injuries, the presence of excessive reactive oxygen species (ROS), prolonged microbial infection, and compromised angiogenesis can contribute to the metabolic reprogramming of macrophages, resulting in a dysregulated inflammatory response that hinders the healing process. In this study, cerium oxide nanoparticles (CeNPs) are encapsulated within a silk fibroin-poly(e-caprolactone) polymer to create an electrospun PSF/CeNPs nanofiber membrane (PSF/membrane). This membrane is further modified through the addition of an angiopoietin-1 mimetic peptide, QHREDGS, resulting in the formation of QPSF/CeNPs (QHREDGS modified PSF/CeNPs membrane). In vitro assessments revealed that the QPSF/CeNPs displayed the intended ability to regulate ROS levels, favorable biocompatibility with cells, promoted endothelial cell attachment and growth, exhibited anti-inflammatory properties through the modulation of macrophage phenotypes from M1 to M2, as well as pro-angiogenetic and antibacterial effects. In vivo, the membrane dressing demonstrated an acceleration of burn wound healing, promotion of angiogenesis, downregulation of inflammatory factors, and enhancement of collagen deposition. This bioactive membrane dressing shows potential as a clinical therapy for promoting the regeneration of both acute and chronically damaged skin tissue., (© 2024 Wiley‐VCH GmbH.)

Hypoxia elicits a multitude of tissue responses depending on the severity and duration of the exposure. While chronic hypoxia is shown to impact development, regeneration, and cancer, the understanding of the threats of acute (i.e., short-term) hypoxia is limited mainly due to its transient nature. Here, a novel gelatin-dextran (Gel-Dex) hydrogel is established that decouples hydrogel formation and oxygen consumption and thus facilitates 3D sprouting from endothelial spheroids and, subsequently, induces hypoxia "on-demand." The Gel-Dex platform rapidly achieves acute moderate hypoxic conditions without compromising its mechanical properties. Acute exposure to hypoxia leads to increased endothelial cell migration and proliferation, promoting the total length and number of vascular sprouts. This work finds that the enhanced angiogenic response is mediated by reactive oxygen species, independently of hypoxia-inducible factors. Reactive oxygen species-dependent matrix metalloproteinases activity mediated angiogenic sprouting is observed following acute hypoxia. Overall, the Gel-Dex hydrogel offers a novel platform to study how "on-demand" acute moderate hypoxia impacts angiogenesis, with broad applicability to the development of novel sensing technologies., (© 2024 The Author(s). Advanced Healthcare Materials published by Wiley‐VCH GmbH.)

Nowadays, the use of monoclonal antibodies to target angiogenic signalling pathways is common, but, unfortunately, the clinical activity of these agents is limited. Thus, the development of approaches targeting multiple pathways for anti-angiogenic effect will lead to increase the clinical benefit. For this purpose, oleuropein, hesperidin, piperine, proanthocyanidins and retinoic acid, which have previously been proven to be bioactive components, anti-angiogenic performances were experimentally tested in retinal pigment epithelial cells. Bioactive ingredients were applied to retinal pigment epithelial cells at varying doses for 48 h, and then IC 50 doses were calculated by MTT analysis. VEGFA and VEGFR1 protein levels were measured by ELISA analysis. Using the RT-PCR technique, the mRNA expression levels of EGF, EGFR, PDGF, PDGFR-β and HIF1A were analysed. Among all bioactive compounds, the bevacizumab group showed the best anti-VEGF activity, followed by the proanthocyanidins and piperine groups. Piperine group showed EGF, PDGF and HIF1A expressions; proanthocyanidins, on the other hand, reduced EGFR, PDGF and HIF1A expressions. Retinoic acid showed an angiogenic effect by increasing VEGFA protein levels and EGF and PDGFR-β expressions. Although hesperidin increased VEGFA protein levels, it decreased EGF, PDGF, PFGFR-β and HIF1A expression levels. Among the bioactive components stated in previous studies to have anti-angiogenic properties, only proanthocyanidins and piperin had anti-VEGF properties. Considering that angiogenesis does not proceed only through VEGF, this study investigated and reported for the first time the effects of relevant bioactive components on angiogenesis through different mechanisms in retinal pigment epithelial cells., (© 2025 The Author(s). Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Background: Hair follicles play a crucial role in hair growth, wound healing, thermoregulation, and sebum production. Hair loss affects millions of people worldwide, yet therapeutic options for managing hair loss and pattern baldness are limited. Isoquercitrin (IQ), a natural small molecule from drinkable Chinese tea, is famous for anti-aging properties., Purpose: This study aimed to explore the potential of IQ in treating and preventing hair loss, along with its underlying mechanisms., Methods: The adult male and female, as well as middle-aged female sprague dawley (SD) rats were used to conduct hair growth experiments in vivo. Signaling pathways and target protein identification were analyzed through western blotting, drug affinity responsive target stability (DARTS), cellular thermal shift assay (CETSA) and surface plasmon resonance (SPR) analyses. Further, the targets were confirmed through in vivo inhibition experiments., Results: IQ is reported here to stimulate anagen phase initiation and hair regrowth by directly interacting with adenosine 5'-monophosphate-activated protein kinase (AMPK) and insulin-like growth factor 1 receptor (IGF-1R). This process involves the AMPK/mammalian target of rapamycin (mTOR)/ unc-51-like autophagy-activating kinase 1 (ULK1) signalling pathway to trigger autophagy and the IGF-1R/phosphatidylinositol 3-kinase (PI3 K)/protein Kinase B (AKT), vascular endothelial growth factor (VEGF)/ vascular endothelial growth factor receptor (VEGFR)/ angiotensin (ANG) pathways to promote angiogenesis in female rats. Furthermore, the hair regrowth efficacy of IQ in adult male rats and middle-aged female rats was verified and shown. Similarly, our findings indicate that IQ promotes hair regrowth in middle-aged rats through autophagy and angiogenesis, akin to its effects in adult rats., Conclusion: AMPK and IGF-1R proteins are identified as the target proteins of IQ and the AMPK/mTOR/ULK1, IGF-1R/PI3K/AKT and VEGF/VEGFR/ANG signalling pathways take important roles in hair growth effect of IQ. Thus, these signaling pathways are crucial for developing future treatments and clinical strategies for hair regeneration., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier GmbH.)

Immunomodulation is essential for implants to regulate tissue regeneration, while bioelectricity plays a fundamental role in regulating immune activities. Under natural preferences, the bone matrix electrical microenvironment is heterogeneous in the nanoscale, which provides fundamental electrical cues to regulate bone immunity and regenerative repair. However, remodeling bone nanoscale heterogeneous electrical microenvironment remains a challenge, and the underlying immune modulation mechanism remains to be explored. In this research, in situ discretely distributed nano-heterojunctions are constructed on titanium oxide nanofibers to mimic the heterogeneous electrical microenvironment exhibited by bone collagen fibers. The material is identified to directly regulate calcium ion channeling for anti-inflammatory polarization of macrophages. Surprisingly, the highly biomimetic heterogeneous electrical microenvironment can induce a pro-angiogenic phenotypic transformation of macrophages, leading to enhanced neo-vascularization at the early stage of osteogenesis. Mechanistic exploration identifies that PI3K signaling pathway-mediated FGF2 secretion may partially explain for strengthened coupling of immunomodulation and angiogenesis, which optimizes subsequent bone regeneration. These findings highlight the significance of biomimetic heterogeneous electrical cues on immune-modulation and provide a design principle for future electroactive implant materials., (© 2024 Wiley‐VCH GmbH.)