Loss of endothelial glucocorticoid receptor promotes angiogenesis via upregulation of Wnt/β-catenin pathway

Exploring the role of dermal sheath cells in wound healing and fibrosis

Wound healing is a complex, dynamic process involving the coordinated interaction of diverse cell types, growth factors, cytokines, and extracellular matrix components. Despite emerging evidence highlighting their importance, dermal sheath cells remain a largely overlooked aspect of wound healing research. This review explores the multifunctional roles of dermal sheath cells in various phases of wound healing, including modulating inflammation, aiding in proliferation, and contributing to extracellular matrix remodelling. Special attention is devoted to the paracrine effects of dermal sheath cells and their role in fibrosis, highlighting their potential in improving healing outcomes, especially in differentiating between hairy and non-hairy skin sites. By drawing connections between dermal sheath cells activity and wound healing outcomes, this work proposes new insights into the mechanisms of tissue regeneration and repair, marking a step forward in our understanding of wound healing processes.

Context is key: glucocorticoid receptor and corticosteroid therapeutics in outcomes after traumatic brain injury

Traumatic brain injury (TBI) is a global health burden, and survivors suffer functional and psychiatric consequences that can persist long after injury. TBI induces a physiological stress response by activating the hypothalamic-pituitary-adrenal (HPA) axis, but the effects of injury on the stress response become more complex in the long term. Clinical and experimental evidence suggests long lasting dysfunction of the stress response after TBI. Additionally, pre- and post-injury stress both have negative impacts on outcome following TBI. This bidirectional relationship between stress and injury impedes recovery and exacerbates TBI-induced psychiatric and cognitive dysfunction. Previous clinical and experimental studies have explored the use of synthetic glucocorticoids as a therapeutic for stress-related TBI outcomes, but these have yielded mixed results. Furthermore, long-term steroid treatment is associated with multiple negative side effects. There is a pressing need for alternative approaches that improve stress functionality after TBI. Glucocorticoid receptor (GR) has been identified as a fundamental link between stress and immune responses, and preclinical evidence suggests GR plays an important role in microglia-mediated outcomes after TBI and other neuroinflammatory conditions. In this review, we will summarize GR-mediated stress dysfunction after TBI, highlighting the role of microglia. We will discuss recent studies which target microglial GR in the context of stress and injury, and we suggest that cell-specific GR interventions may be a promising strategy for long-term TBI pathophysiology.

CD73-positive pediatric urethral mesenchymal stem-like cell-derived small extracellular vesicles stimulate angiogenesis

Introduction

Angiogenesis plays an important role in the repair of urethral injury, and stem cells and their secretomes can promote angiogenesis. We obtained pediatric urethral mesenchymal stem-like cells (PU-MSLCs) in an earlier study. This project studied the pro-angiogenic effect of PU-MSLC-derived small extracellular vesicles (PUMSLC-sEVs) and the underlying mechanisms.

Materials and methods

PUMSLCs and PUMSLC-sEVs were cultivated and identified. Then, biological methods such as the ethynyl deoxyuridine (EdU) incorporation assay, Cell Counting Kit-8 (CCK-8) assay, scratch wound assay, Transwell assay, and tube formation assay were used to study the effect of PUMSLC-sEVs on the proliferation, migration, and tube formation of human umbilical vein endothelial cells (HUVECs). We explored whether the proangiogenic effect of PUMSLC-sEVs is related to CD73 and whether adenosine (ADO, a CD73 metabolite) promoted angiogenesis. GraphPad Prism 8 software was used for data analysis.

Results

We observed that PUMSLC-sEVs significantly promoted the proliferation, migration, and tube-forming abilities of HUVECs. PUMSLC-sEVs delivered CD73 molecules to HUVECs to promote angiogenesis. The angiogenic ability of HUVECs was enhanced after treatment with extracellular ADO produced by CD73, and PUMSLC-sEVs further promoted angiogenesis by activating Adenosine Receptor A2A (A2AR).

Conclusions

These observations suggest that PUMSLC-sEVs promote angiogenesis, possibly through activation of the CD73/ADO/A2AR signaling axis.

Ischemia-reperfusion injury: molecular mechanisms and therapeutic targets

Ischemia-reperfusion (I/R) injury paradoxically occurs during reperfusion following ischemia, exacerbating the initial tissue damage. The limited understanding of the intricate mechanisms underlying I/R injury hinders the development of effective therapeutic interventions. The Wnt signaling pathway exhibits extensive crosstalk with various other pathways, forming a network system of signaling pathways involved in I/R injury. This review article elucidates the underlying mechanisms involved in Wnt signaling, as well as the complex interplay between Wnt and other pathways, including Notch, phosphatidylinositol 3-kinase/protein kinase B, transforming growth factor-β, nuclear factor kappa, bone morphogenetic protein, N-methyl-D-aspartic acid receptor-Ca2+-Activin A, Hippo-Yes-associated protein, toll-like receptor 4/toll-interleukine-1 receptor domain-containing adapter-inducing interferon-β, and hepatocyte growth factor/mesenchymal-epithelial transition factor. In particular, we delve into their respective contributions to key pathological processes, including apoptosis, the inflammatory response, oxidative stress, extracellular matrix remodeling, angiogenesis, cell hypertrophy, fibrosis, ferroptosis, neurogenesis, and blood-brain barrier damage during I/R injury. Our comprehensive analysis of the mechanisms involved in Wnt signaling during I/R reveals that activation of the canonical Wnt pathway promotes organ recovery, while activation of the non-canonical Wnt pathways exacerbates injury. Moreover, we explore novel therapeutic approaches based on these mechanistic findings, incorporating evidence from animal experiments, current standards, and clinical trials. The objective of this review is to provide deeper insights into the roles of Wnt and its crosstalk signaling pathways in I/R-mediated processes and organ dysfunction, to facilitate the development of innovative therapeutic agents for I/R injury.

miR-29c-3p represses the angiogenesis of esophageal squamous cell carcinoma by targeting SERPINH1 to regulate the Wnt signaling pathway

PURPOSE

Esophageal squamous cell carcinoma (ESCC) is characterized by early metastasis and late diagnosis. miR-29c-3p is confirmed to repress angiogenesis in multiple tumor types. Yet, the functions of miR-29c-3p in the mechanism of ESCC angiogenesis, which were not sufficiently explored previously, were exactly what we investigated here at the molecular level.

METHODS

The mRNA level of miR-29c-3p and Serpin peptidase inhibitor clade H member 1 (SERPINH1) in ESCC tissues were assessed via bioinformatics analysis. Thereafter, miR-29c-3p and SERPINH1 (HSP47) mRNA level in ESCC cell lines was evaluated via quantitative real-time polymerase chain reaction. The effects of abnormal miR-29c-3p and SERPINH1 expression on ESCC cell viability, proliferation, migration, invasion, and HUVEC angiogenesis were examined via CCK8, colony formation, transwell, and angiogenesis assays, respectively. The protein levels of SERPINH1, vascular endothelial growth factor-A (VEGFA), Wnt-1, ?-catenin, and p-?-catenin were evaluated via Western blot. Expression of VEGFA secreted by ESCC cells was measured via enzyme-linked immunosorbent assay. Treatment with the Wnt activator BML-284 further revealed the way miR-29c-3p mediated the Wnt signaling pathway and its effects on angiogenesis.

RESULTS

Herein, we revealed a decrease of miR-29c-3p expression in ESCC tissues and cells, while the overexpressed miR-29c-3p could remarkably suppress ESCC cell progression, as well as HUVEC angiogenesis. Meanwhile, overexpressed miR-29c-3p notably downregulated VEGFA and repressed the Wnt signaling pathway. Treatment with the Wnt activator BML-284 could reverse the inhibition of HUVEC angiogenesis caused by miR-29c-3p. SERPINH1 was a downstream target of miR-29c-3p. SERPINH1 knockdown suppressed the malignant phenotypes of ESCC cells and impeded the Wnt signaling activation, while such suppression was reversed through miR-29c-3p inhibitor.

CONCLUSIONS

We confirmed the mechanism that miR-29c-3p targeted SERPINH1, thus regulating angiogenesis in ESCC through the Wnt signaling pathway. It improves the understanding of angiogenesis in ESCC and offers new ideas for the research of ESCC treatment strategies in the future.

Paeoniflorin suppresses the apoptosis and inflammation of human coronary artery endothelial cells induced by oxidized low-density lipoprotein by regulating the Wnt/β-catenin pathway

CONTEXT

Paeoniflorin (PF) contributes to improving coronary artery disease (CAD).

OBJECTIVE

This study clarified the efficiency of PF in CAD and the molecular mechanism.

MATERIALS AND METHODS

Human coronary artery endothelial cells (HCAECs) were treated with oxidized low-density lipoprotein (ox-LDL; 20, 40, 80 and 160 μg/mL) and PF (0.05, 0.1 0.2 and 0.4 mM). To study cell phenotypes, HCAECs were treated with 80 μg/mL ox-LDL with or without 0.1 mM PF for 24 h, and cell viability and apoptosis were evaluated using the methyl thiazolyl tetrazolium (MTT) assay and flow cytometry, respectively. In addition, inflammatory cytokines levels were measured by enzyme-linked immunosorbent assay (ELISA). Western blot evaluated the Wnt/β-catenin pathway-related factors.

RESULTS

ox-LDL and PF (0.2 and 0.4 mM) suppressed cell viability in a dose-dependent manner. The IC50 value of PF was 722.9 nM. PF facilitated cell viability (115.76%), inhibited apoptosis (46.28%), reduced IL-6 (63.43%) and IL-8 (66.70%) levels and increased IL-10 levels (181.15%) of ox-LDL-treated HCAECs. Additionally, PF inactivated the Wnt/β-catenin pathway, and XAV939 treatment further promoted cell viability (120.54%), suppressed apoptosis (56.92%), reduced the levels of IL-6 (76.16%) and IL-8 (86.82%) and increased the IL-10 levels (120.22%) of ox-LDL-induced HCAECs after PF treatment. Moreover, PF alleviated plaque lesions of the aorta and aorta root and serum lipid of ApoE-/- mice with a high-fat diet.

DISCUSSION AND CONCLUSIONS

This study first revealed that PF inhibited ox-LDL-induced HCAECs apoptosis and inflammation via the Wnt/β-catenin pathway and alleviated CAD, suggesting the potential of PF as a drug for CAD treatment.

PHGDH promotes esophageal squamous cell carcinoma progression via Wnt/β-catenin pathway

PURPOSE

Esophageal squamous carcinoma (ESCC) with a high incidence in China, lacks effective therapeutic targets. Phosphoglycerate dehydrogenase (PHGDH) is a key enzyme in serine biosynthesis. However, the biological role of PHGDH in ESCC has not been revealed.

METHODS

The expression of PHGDH in ESCC was investigated by UALCAN. The relationship between PHGDH expression and its prognostic value was analyzed by Kaplan-Meier and univariate Cox regression. Further, the potential functions of PHGDH involved in ESCC were explored through DAVID database and GSEA software. In addition, the expression of PHGDH was verified in ESCC. Then, the effects of PHGDH knockdown on ESCC were evaluated in vitro and in vivo by cell proliferation, clone formation, cell cycle, apoptosis, tube formation assays and ESCC cells derived xenograft model. In addition, western blotting and immunohistochemistry were used to detect the expression of Wnt/β-catenin pathway which was associated with PHGDH.

RESULTS

Bioinformatics analysis found that PHGDH was highly expressed in ESCC, and meaningfully, patients with high PHGDH expression had a poor prognosis. Moreover, the overexpression of PHGDH was verified in ESCC. Afterwards, PHGDH knockdown inhibited the cell proliferation, induced cell cycle arrest and apoptosis in ESCC cells, and inhibited the angiogenesis of HUVECs induced by ESCC conditioned medium, as well as inhibited the growth of xenograft tumor. Mechanistically, PHGDH knockdown inhibited Wnt/β-catenin signaling pathway in ESCC.

CONCLUSION

High expression of PHGDH predicts a poor prognosis for ESCC. PHGDH knockdown inhibits ESCC progression by suppressing Wnt/β-catenin signaling pathway, indicating that PHGDH might be a potential target for ESCC therapy.

Overexpression of FoxM1 Enhanced the Protective Effect of Bone Marrow-Derived Mesenchymal Stem Cells on Lipopolysaccharide-Induced Acute Lung Injury through the Activation of Wnt/β-Catenin Signaling

Background

Mesenchymal stem cell- (MSC-) based cell and gene therapies have made remarkable progress in alleviating acute lung injury/acute respiratory distress syndrome (ALI/ARDS). However, the benefits of Forkhead box protein M1 (FoxM1) gene-modified MSCs in the treatment of ALI have not been studied.

Methods

We evaluated the therapeutic effects of FoxM1-modified MSCs in ALI mice induced by lipopolysaccharide (LPS) by quantifying the survival rate, lung weight ratio (wet/dry), and contents of bronchoalveolar lavage fluid. In addition, microcomputed tomography, histopathology, Evans Blue assay, and quantification of apoptosis were performed. We also explored the underlying mechanism by assessing Wnt/β-catenin signaling following the treatment of mice with FoxM1-modified MSCs utilizing the Wnt/β-catenin inhibitor XAV-939.

Results

Compared with unmodified MSCs, transplantation of FoxM1-modified MSCs improved survival and vascular permeability; reduced total cell counts, leukocyte counts, total protein concentrations, and inflammatory cytokines in BALF; attenuated lung pathological impairments and fibrosis; and inhibited apoptosis in LPS-induced ALI/ARDS mice. Furthermore, FoxM1-modified MSCs maintained vascular integrity during ALI/ARDS by upregulating Wnt/β-catenin signaling, which was partly reversed via a pathway inhibitor.

Conclusion

Overexpression of FoxM1 optimizes the treatment action of MSCs on ALI/ARDS by inhibiting inflammation and apoptosis and restoring vascular integrity partially through Wnt/β-catenin signaling pathway stimulation.

T-2 toxin inhibits osteoblastic differentiation and mineralization involving mutual regulation between Wnt signaling pathway and autophagy

Mycotoxins are most frequent contaminants in environment and agricultural production globally. The T-2 toxin of Fusarium species is the most toxic type of A trichothecene mycotoxins. T-2 toxin can accumulate in bone and cause bone development disorders. Osteoblast is the functional cell responsible for bone formation. Whereas, the mechanism of T-2 toxin toxicity on osteoblast remains unknown. In present study, MC3T3-E1 cells were treated with 0, 2, 4, and 8 nM T-2 toxin for 24h to explore the effect of T-2 toxin on the differentiation and mineralization of osteoblasts. Subsequently, autophagy and Wnt intervention agents were used to explore the roles of autophagy and Wnt signaling pathway in T-2 toxin-induced osteoblastic differentiation and mineralization disorders, respectively. The results showed that 2 nM of T-2 toxin had no significant effect on cell vitality, but 4 and 8 nM of T-2 significantly inhibited cell viability. All doses of T-2 toxin inhibited both osteoblastic differentiation and mineralization, as assessed by alkaline phosphatase staining, Alizarin red S staining, and protein expressions of osteogenic proteins. In addition, the activation of Wnt signaling pathway mitigated T-2 toxin-induced osteoblast impairment, while the inhibition of autophagy exacerbated it. Our results also indicated that there was a positive feedback loop between the Wnt signaling pathway and autophagy.

Restoration of Mitochondrial Function Is Essential in the Endothelium-Dependent Vasodilation Induced by Acacetin in Hypertensive Rats

Mitochondrial dysfunction in the endothelium contributes to the progression of hypertension and plays an obligatory role in modulating vascular tone. Acacetin is a natural flavonoid compound that has been shown to possess multiple beneficial effects, including vasodilatation. However, whether acacetin could improve endothelial function in hypertension by protecting against mitochondria-dependent apoptosis remains to be determined. The mean arterial pressure (MAP) in Wistar Kyoto (WKY) rats, spontaneously hypertensive rats (SHR) administered with acacetin intraperitoneally for 2 h or intragastrically for six weeks were examined. The endothelial injury was evaluated by immunofluorescent staining and a transmission electron microscope (TEM). Vascular tension measurement was performed to assess the protective effect of acacetin on mesenteric arteries. Endothelial injury in the pathogenesis of SHR was modeled in HUVECs treated with Angiotensin II (Ang II). Mitochondria-dependent apoptosis, the opening of Mitochondrial Permeability Transition Pore (mPTP) and mitochondrial dynamics proteins were determined by fluorescence activated cell sorting (FACS), immunofluorescence staining and western blot. Acacetin administered intraperitoneally greatly reduced MAP in SHR by mediating a more pronounced endothelium-dependent dilatation in mesenteric arteries, and the vascular dilatation was reduced remarkably by NG-nitro-L-arginine methyl ester (L-NAME), an inhibitor of NO synthesis. While acacetin administered intragastrically for six weeks had no apparent effect on MAP, it improved the endothelium-dependent dilatation in SHR by activating the AKT/eNOS pathway and protecting against the abnormalities of endothelium and mitochondria. Furthermore, acacetin remarkably inhibited Ang II induced apoptosis by inhibiting the increased expression of Cyclophilin D (CypD), promoted the opening of mPTP, ROS generation, ATP loss and disturbance of dynamin-related protein 1 (DRP1)/optic atrophy1 (OPA1) dynamics in HUVECs. This study suggests that acacetin protected against endothelial dysfunction in hypertension by activating the AKT/eNOS pathway and modulating mitochondrial function by targeting mPTP and DRP1/OPA1-dependent dynamics.

CAV1 alleviated CaOx stones formation via suppressing autophagy-dependent ferroptosis

Background

Calcium oxalate (CaOx) is the most common type of kidney stone, but the mechanism of CaOx stones formation remains unclear. The injury of renal cells such as ferroptosis and autophagy has been considered a basis for stones formation.

Methods

We conducted transmission electron microscope (TEM), reactive oxygen species (ROS), malondialdehyde (MDA), glutathione (GSH), and C11-BODIPY analysis to explore whether CaOx could induce autophagy-dependent ferroptosis in vivo and in vitro. To explore the possible mechanism, we conducted bioinformatic analysis of patients with or without CaOx stones, Western blot and qPCR were used to identify the different genes we found in bioinformatic analysis.

Results

In our study, we found that CaOx could induce autophagy-dependent ferroptosis no matter in vivo or in vitro, which might finally lead to urolithiasis. Bioinformatic analysis of the GSE73680 dataset indicated that the expression of caveolin-1 (CAV1) was higher in control patients than CaOx stone patients, the STRING database indicated that CAV1 might interact with low density lipoprotein receptro-related protein 6 (LRP6), Gene Set Enrichment Analysis (GSEA) showed that the WNT pathway positively associated with the control group while negatively related to the stone group, and LRP6 was the core gene of the WNT pathway. Western blot found that CAV1, LRP6, and Wnt/β-Catenin were decreased in Human Kidney2 (HK2) cells stimulated with CaOx. Furthermore, the WNT pathway was considered to be involved in autophagy and ferroptosis.

Conclusions

We presumed that CAV1 could ameliorate autophagy-dependent ferroptosis through the LRP6/Wnt/β-Catenin axis, and finally alleviate CaOx stone formation.

Biomechanical regulation of planar cell polarity in endothelial cells

Cell polarity refers to the uneven distribution of certain cytoplasmic components in a cell with a spatial order. The planar cell polarity (PCP), the cell aligns perpendicular to the polar plane, in endothelial cells (ECs) has become a research hot spot. The planar polarity of ECs has a positive significance on the regulation of cardiovascular dysfunction, pathological angiogenesis, and ischemic stroke. The endothelial polarity is stimulated and regulated by biomechanical force. Mechanical stimuli promote endothelial polarization and make ECs produce PCP to maintain the normal physiological and biochemical functions. Here, we overview recent advances in understanding the interplay and mechanism between PCP and ECs function involved in mechanical forces, with a focus on PCP signaling pathways and organelles in regulating the polarity of ECs. And then showed the related diseases caused by ECs polarity dysfunction. This study provides new ideas and therapeutic targets for the treatment of endothelial PCP-related diseases.

Caspase-4/11 is critical for angiogenesis by repressing Notch1 signaling via inhibiting γ-secretase activity

BACKGROUND AND PURPOSE

Notch1 activation mediated by γ-secretase is critical for angiogenesis. GeneCards database predicted that Caspase-4 (CASP4, with murine ortholog CASP11) interacts with presenilin-1, the catalytic core of γ-secretase. Therefore, we investigated the role of CASP4/11 in angiogenesis.

EXPERIMENTAL APPROACH

In vivo, we studied the role of Casp11 in several angiogenesis mouse models using Casp11 wild-type and knockout mice. In vitro, we detected the effects of CASP4 on endothelial functions and Notch signaling by depleting or overexpressing CASP4 in human umbilical vein endothelial cells (HUVECs). The functional domain responsible for the binding of CASP4 and presenilin-1 was detected by mutagenesis and co-immunoprecipitation.

KEY RESULTS

Casp11 deficiency remarkably impaired adult angiogenesis in ischemic hindlimbs, melanoma xenografts and Matrigel plugs, but not the developmental angiogenesis of retina. Bone marrow transplantation revealed that the pro-angiogenic effect depended on CASP11 derived from non-hematopoietic cells. CASP4 expression was induced by inflammatory factors and CASP4 knockdown decreased cell viability, proliferation, migration and tube formation in HUVECs. Mechanistically, CASP4/11 deficiency increased Notch1 activation in vivo and in vitro, while CASP4 overexpression repressed Notch1 signaling in HUVECs. Moreover, CASP4 knockdown increased γ-secretase activity. γ-Secretase inhibitor DAPT restored the effects of CASP4 siRNA on Notch1 activation and angiogenesis in HUVECs. Notably, the catalytic activity of CASP4/11 was dispensable. Instead, CASP4 directly interacted with presenilin-1 through the caspase recruitment domain (CARD).

CONCLUSIONS AND IMPLICATIONS

These findings reveal a critical role of CASP4/11 in adult angiogenesis and make this molecule a promising therapeutic target for angiogenesis-related diseases in the future.

Autophagy in muscle regeneration: potential therapies for myopathies

Autophagy classically functions as a physiological process to degrade cytoplasmic components, protein aggregates, and/or organelles, as a mechanism for nutrient breakdown, and as a regulator of cellular architecture. Its biological functions include metabolic stress adaptation, stem cell differentiation, immunomodulation and diseases regulation, and so on. Current researches have proved that autophagy dysfunction may contribute to the pathogenesis of some myopathies through impairment of myofibres regeneration. Studies of autophagy inhibition also indicate the importance of autophagy in muscle regeneration, while activation of autophagy can restore muscle function in some myopathies. In this review, we aim to report the mechanisms of action of autophagy on muscle regeneration to provide relevant references for the treatment of regenerating defective myopathies by regulating autophagy. Results have shown that one key mechanism of autophagy regulating the muscle regeneration is to affect the differentiation fate of muscle stem cells (MuSCs), including quiescence maintenance, activation and differentiation. The roles of autophagy (organelle/protein degradation, energy facilitation, and/or other) vary at different myogenic stages of the repair process. When the muscle is in homeostasis, basal autophagy can maintain the quiescence state and stemness of MuSCs by renewing organelle and protein. After injury, the increased autophagy flux contributes to meet biological energy demand of MuSCs during activation and proliferation. By mitochondrial remodelling, autophagy during differentiation can promote the metabolic transformation and balance mitochondrial-mediated apoptosis signals in myoblasts. Autophagy in mature myofibres is also essential for the degradation of necrotic myofibres, and may affect the dynamics of MuSCs by affecting the secretion spectrum of myofibres or the recruitment of supporting cells. Except for myogenic cells, autophagy also plays an important role in regulating the function of non-myogenic cells in the muscle microenvironment, which is also essential for successful muscle recovery. Autophagy can regulate the immune microenvironment during muscle regeneration through the recruitment and polarization of macrophages, while autophagy in endothelial cells can regulate muscle regeneration in an angiogenic or angiogenesis-independent manner. Drug or nutrition targeted autophagy has been preliminarily proved to restore muscle function in myopathies by promoting muscle regeneration, and further understanding the role and mechanism of autophagy in various cell types during muscle regeneration will enable more effective combinatorial therapeutic strategies.

Role of Endothelial Glucocorticoid Receptor in the Pathogenesis of Kidney Diseases

Glucocorticoids, as multifunctional hormones, are widely used in the treatment of various diseases including nephrological disorders. They are known to affect immunological cells, effectively treating many autoimmune and inflammatory processes. Furthermore, there is a growing body of evidence demonstrating the potent role of glucocorticoids in non-immune cells such as podocytes. Moreover, novel data show additional pathways and processes affected by glucocorticoids, such as the Wnt pathway or autophagy. The endothelium is currently considered as a key organ in the regulation of numerous kidney functions such as glomerular filtration, vascular tone and the regulation of inflammation and coagulation. In this review, we analyse the literature concerning the effects of endothelial glucocorticoid receptor signalling on kidney function in health and disease, with special focus on hypertension, diabetic kidney disease, glomerulopathies and chronic kidney disease. Recent studies demonstrate the potential role of endothelial GR in the prevention of fibrosis of kidney tissue and cell metabolism through Wnt pathways, which could have a protective effect against disease progression. Another important aspect covered in this review is blood pressure regulation though GR and eNOS. We also briefly cover potential therapies that might affect the endothelial glucocorticoid receptor and its possible clinical implications, with special interest in selective or local GR stimulation and potential mitigation of GC treatment side effects.

Icariin activates autophagy to trigger TGFβ1 upregulation and promote angiogenesis in EA.hy926 human vascular endothelial cells

Angiogenesis plays an important role in tissue development and repair, and how to regulate angiogenesis effectively is a widely studied problem in the biomedical field. In recent years, the role of autophagy in vascular endothelial cells has attracted extensive attention. Icariin (ICA) is a traditional Chinese medicine that has been proven to have outstanding protective effects on the vascular system and to regulate cellular autophagy effectively. However, at present, it has not been reported whether ICA can affect the angiogenic ability of endothelial cells by affecting autophagy. In this study, we aimed to investigate whether ICA affects the angiogenesis capacity of EA.hy926 human vascular endothelial cells through autophagy and explain the underlying potential mechanisms. First, we determined that ICA at appropriate concentrations has the ability to promote cell migration and angiogenesis using wound healing assays and tube formation assays. Then, at the molecular level, we observed the upregulation of VEGFA, VEGFR2, ANGI, ANGII, and Tie2 mRNA and detected the upregulation of TGFβ1 protein by Western blotting. We also demonstrated that angiogenic concentrations of ICA can effectively activate autophagy. The autophagy inhibitor 3-MA significantly suppressed TGFβ1 expression and tube formation in EA.hy926 cells. Overall, we hope that our studies might help to further understand the effect of ICA on vascular endothelial cells and provide a theoretical basis for future angiogenic applications of ICA

Blockade of Autophagy Prevents the Development and Progression of Peritoneal Fibrosis

Peritoneal fibrosis (PF) is a major cause of ultrafiltration failure in long-term peritoneal dialysis (PD) patients. Nevertheless, limited measures have been shown to be effective for the prevention and treatment of PF. Some views reveal that activation of autophagy ameliorates PF but others demonstrate that autophagy promotes PF. It is obvious that the role of autophagy in PF is controversial and further studies are needed. Here, we investigated the role of autophagy in rat models of PF and damaged cultured human peritoneal mesothelial cells (HPMCs). Autophagy was highly activated in fibrotic peritoneum from two PF rat models induced by 4.25% peritoneal dialysate fluid (PDF) and 0.1% chlorhexidine gluconate (CG). Blockade of autophagy with 3-MA effectively prevented PF in both models and reversed epithelial to mesenchymal transition (EMT) by down-regulating TGF-β/Smad3 signaling pathway and downstream nuclear transcription factors Slug and Snail. Treatment with 3-MA also inhibited activation of EGFR/ERK1/2 signaling pathway during PF. Moreover, 3-MA prominently decreased STAT3/NF-κB-mediated inflammatory response and macrophage infiltration, and prevented peritoneal angiogenesis through downregulation of β-catenin signal. In addition, TGF-β1 stimulation up-regulated autophagic activity as evidenced by the increased autophagosome in vitro. Exposure of HPMCs to TGF-β1 resulted in the induction of EMT and activation of TGF-β/Smad3, EGFR/ERK1/2 signaling pathways. Treatment with 3-MA blocked all these responses. In addition, delayed administration of 3-MA was effective in reducing EMT induced by TGF-β1. Taken together, our study indicated that autophagy might promote PF and 3-MA had anti-fibrosis effect in vivo and in vitro. These results suggest that autophagy could be a potential target on PF therapy for clinical patients with long-term PD.