Angiopoietins as Predictor Indexes in COVID-19 Patients in Delta and Omicron Waves.

This study aimed to explore the correlation between Angiopoietin-1 (Ang-1) and Angiopoietin-2 (Ang-2) concentrations and the Angiopoietin-2/Angiopoietin-1 ratio (Ang-2/Ang-1) with clinical outcomes, potentially serving as disease severity and survival biomarkers. A study at AHEPA University Hospital involved 90 Coronavirus Disease 2019 (COVID-19) adult patients, 30 hospitalized intensive care units (ICU), 30 inward units (non-ICU), and 30 asymptomatic non-hospitalized individuals as controls. Estimated endothelial dysfunction markers related to angiogenesis were measured. There was a statistically significant difference only between outpatient and hospitalized patients (non-ICU-ICU groups) for the Ang-1 and Ang-2 indices. The Ang-2/Ang-1 ratio has differed significantly among the individual patient groups. An ROC analysis was conducted to find an optimal threshold for distinguishing between (outpatients-non-ICU) and (non-ICU-ICU) groups. It was based on Youden's index of 0.1122 and 0.3825, respectively. The Ang-1, Ang-2 levels, and Ang-2/Ang-1 ratio were analyzed as severity indicators in COVID-19 patients. The Ang-2/Ang-1 ratio demonstrated better prognostic and diagnostic utility than individual biomarker levels. Monitoring the Ang-2/Ang-1 ratio can identify COVID-19 patients at risk and assist clinicians in tailoring treatment strategies to improve outcomes.

Angiopoietin 1 Relieves Osteolysis by Promoting Macrophage Mitophagy Through the TBK1-SQSTM1 Pathway to Inhibit AIM2 Inflammasome-Mediated Pyroptosis.

Osteolysis resulting from wear particles and subsequent aseptic loosening is a leading cause of revision surgery of artificial joints. The underlying pathogenesis of particle-induced osteolysis (PPO) has remained largely uncertain. Addressing how to mitigate osteolysis caused by wear particles presents a significant challenge for orthopedic surgeons. This study aimed to explore the molecular mechanism by which Angiopoietin (Ang-1) inhibits osteoclast activation to alleviate osteolysis. RAW264.7 mouse macrophages were stimulated with LPS or RANKL to induce osteoclast formation. Additionally, titanium (Ti) particles (50 mg) were subperiosteally implanted around the cranial suture of mice to establish a calvarial osteolysis model. Ang-1, a member of the pro-angiogenic factor protein family and an important inflammatory regulator molecule, was utilized in this model. TRAP staining was utilized to detect osteoclast activation, while a western blot was conducted to identify key proteins associated with mitophagy and pyroptosis. Scanning electron microscopy was employed to observe the morphology and dimensions of Ti particles. Additionally, a combination of micro-CT, H&E, Masson's trichrome, and immunohistochemical staining techniques were applied to analyze the calvarial samples. Results indicated that Ang-1 could inhibit LPS- or RANKL-induced osteoclastogenesis and alleviate Ti particle-induced calvarial osteolysis in mice. TBK-1, a key signaling molecule involved in initiating mitophagy, was found to be mechanistically enhanced by Ang-1 through promoting TBK-1 phosphorylation in macrophages. This process inhibited AIM2 inflammasome-mediated pyroptosis and impeded osteoclastogenesis. Overall, this research uncovers a novel mechanism by which Ang-1 can attenuate inflammatory osteolysis, potentially offering a new therapeutic approach for PPO.

Cold atmospheric plasma induces the curing mechanism of diabetic wounds by regulating the oxidative stress mediators iNOS and NO, the pyroptotic mediators NLRP-3, Caspase-1 and IL-1ß and the angiogenesis mediators VEGF and Ang-1.

It has been demonstrated that cold atmospheric plasma (CAP) accelerates the wound healing process, however the underlying molecular pathways behind this effect remain unclear. Thus, the goal of the proposed investigation is to elucidate the therapeutic advantages of CAP on angiogenesis, pyroptotic, oxidative stress, and inflammatory mediators during the wound-healing mechanisms associated with diabetes. Intraperitoneal administration of streptozotocin (STZ, 60 mg/Kg) of body weight was used to induce type-1 diabetes. Seventy-five male mice were randomized into 3 groups: the control non-diabetic group, the diabetic group that was not treated, and the diabetic group that was treated with CAP. The key mediators of pyroptosis and its impact on the slow healing process of diabetic wounds were examined using histological investigations employing H&E staining, immunohistochemistry, ELISA, and Western blotting analysis. Angiogenesis proteins (VEGF, Ang-1, and HO-1) showed a significant decline in expression concentrations in the diabetic wounds, indicating that diabetic animals' wounds were less likely to heal. Furthermore, compared to the controls, the major mediators of pyroptosis (NLRP-3, IL-1ß, and caspase-1), oxidative stress (iNOS and NO), and inflammation (TNF-α and IL-6) have higher expression levels in the diabetic wounds. These factors substantially impede the healing mechanism of diabetic wounds. Interestingly, our results disclosed the therapeutic impacts of CAP treatment in the healing process of diabetic wounds via significantly regulating the expression levels of angiogenesis, pyroptosis, oxidative stress and pro-inflammatory mediators. Our findings demonstrated the curative likelihood of CAP and the underlying mechanisms for enhancing the healing process of diabetic wounds.

Glycation of fibronectin impairs angiopoietin-1/Tie-2 signaling through uncoupling Tie-2-α5ß1 integrin crosstalk.

The dysfunction of angiopoietin-1 (Ang-1)/Tie-2 signaling pathways has been implicated in diabetic complications. However, the underlying molecular mechanisms remain unclear. Fibronectin (FN) is thought to have an important role in regulating Ang-1/Tie-2 signaling activation. But no previous study has investigated the effects of FN glycation on Ang-1/Tie-2 signaling. In the present study, FN was glycated by methylglyoxal (MGO) to investigate whether the glycation of FN contributes to diabetes-induced Ang-1/Tie-2 signaling impairment and to understand the molecular mechanisms involved. The results demonstrated that MGO-glycated FN significantly impaired Ang-1-evoked phosphorylation of Tie-2 and Akt, Ang-1-induced endothelial cell migration and tube formation and Ang-1-mediated cell survival. The glycation of FN also inhibited the binding of α5ß1 integrin to Tie-2. Moreover, FN was remarkably modified by AGEs in aortae derived from db/db mice, indicating the glycation of FN in vivo. Ang-1-induced aortic ring vessel outgrowth and Ang-1-mediated cell survival were also both significantly inhibited in aortae from db/db mice compared to that from the wild type littermates. Moreover, FN, rather than glycated FN partly restored aortic ring angiogenesis in db/db mice, indicating that the angiogenesis defect in the db/db mice are due to FN glycation. Collectively, the results in the present study suggest that the glycation of FN impairs Ang-1/Tie-2 signaling pathway by uncoupling Tie-2-α5ß1 integrin crosstalk. This may provide a mechanism for Ang-1/Tie-2 signaling dysfunction and angiogenesis failure in diabetic ischaemic diseases.

Angiopoietin-2 binds to multiple interactive sites within von Willebrand factor.

Background: Biosynthesis of von Willebrand factor (VWF) in endothelial cells drives the formation of storage-organelles known as Weibel-Palade bodies (WPBs). WPBs also contain several other proteins, including angiopoietin-2 (Ang-2). Objectives: At present, the molecular basis of the VWF-Ang-2 interaction is poorly understood. Here, we used immunosorbent-binding assays and specific recombinant VWF fragments to analyze VWF-Ang-2 interactions. Results: We found that VWF bound to immobilized Ang-2 most efficiently (half-maximal binding at 0.5 ± 0.1 µg/mL) under conditions of high CaCl2 (10 mM) and slightly acidic pH (6.4-7.0). Interestingly, several isolated recombinant VWF domains (A1/Fc, A2/Fc, D4/Fc, and D'D3-HPC4) displayed dose-dependent binding to immobilized Ang-2. Binding appeared specific, as antibodies against D'D3, A1, and A2 significantly reduced the binding of these domains to Ang-2. Complexes between VWF and Ang-2 in plasma could be detected by immunoprecipitation- and immunosorbent assays. Unexpectedly, control experiments also revealed complexes between VWF and angiopoietin-1 (Ang-1), a protein structurally homologous to Ang-2. Furthermore, direct binding studies showed dose-dependent binding of VWF to immobilized Ang-1 (half-maximal binding at 1.8 ± 1.0 µg/mL). Interestingly, rather than competing for Ang-1 binding, Ang-2 enhanced the binding of VWF to Ang-1 about 3-fold. Competition experiments further revealed that binding to VWF does not prevent Ang-1 and Ang-2 from binding to Tie-2. Conclusion: Our data show that both Ang-1 and Ang-2 bind to VWF, seemingly using different interactive sites. Ang-2 modulates the binding of VWF to Ang-1, the (patho)-physiological consequences of which remain to be investigated.

Heating of the neck or elbows alleviates Raynaud's phenomenon but has different effects on different types of patients with systemic sclerosis.

OBJECTIVES: We previously reported that heating of the neck or elbows alleviated Raynaud's phenomenon in patients with systemic sclerosis and upregulated capillary extension factor angiopoietin-1 (Angpt-1) in the fingertips. Here, we investigated which cases responded better to the effect of heating of the neck or elbows. METHODS: The pre- to post-heating change in the visual analogue scale for Raynaud's phenomenon (ΔVAS) was examined for correlation with age, disease duration, autoantibodies, disease types, corticosteroid dose, capillaroscopic nailfold capillary damage, fingertip Angpt-1 concentrations at baseline, and increased rate of Angpt-1 concentration. RESULTS: The ΔVAS for elbow heating correlated positively with the baseline Angpt-1 concentration, whereas the opposite correlation was observed for neck heating. The other items were not significantly correlated with the ΔVAS; however, the ΔVAS for elbow heating tended to be larger in patients with advanced capillary damage, whereas the opposite trend was observed for neck heating. CONCLUSIONS: Elbow and neck heating alleviated Raynaud's phenomenon to a similar extent, but their mechanism was different. Heating the elbows had a greater effect on patients with advanced capillary damage and lower fingertip Angpt-1 concentrations.

Dual gene-activated dermal scaffolds regulate angiogenesis and wound healing by mediating the coexpression of VEGF and angiopoietin-1.

The vascularization of dermal substitutes is a key challenge in efforts to heal deep skin defects. In this study, dual gene-activated dermal scaffolds (DGADSs-1) were fabricated by loading nanocomposite particles of polyethylenimine (PEI)/multiple plasmid DNAs (pDNAs) encoding vascular endothelial growth factor and angiopoietin-1 at a ratio of 1:1. In a similar manner, DGADSs-2 were loaded with a chimeric plasmid encoding both VEGF and Ang-1. In vitro studies showed that both types of DGADSs released PEI/pDNA nanoparticles in a sustained manner; they demonstrated effective transfection ability, leading to upregulated expression of VEGF and Ang-1. Furthermore, both types of DGADSs promoted fibroblast proliferation and blood vessel formation, although DGADSs-1 showed a more obvious promotion effect. A rat full-thickness skin defect model showed that split-thickness skin transplanted using a one-step method could achieve full survival at the 12th day after surgery in both DGADSs-1 and DGADSs-2 groups, and the vascularization time of dermal substitutes was significantly shortened. Compared with the other three groups of scaffolds, the DGADSs-1 group had significantly greater cell infiltration, collagen deposition, neovascularization, and vascular maturation, all of which promoted wound healing. Thus, compared with single-gene-activated dermal scaffolds, DGADSs show greater potential for enhancing angiogenesis. DGADSs with different loading modes also exhibited differences in terms of angiogenesis; the effect of loading two genes (DGADSs-1) was better than the effect of loading a chimeric gene (DGADSs-2). In summary, DGADSs, which continuously upregulate VEGF and Ang-1 expression, offer a new functional tissue-engineered dermal substitute with the ability to activate vascularization.

Refractory kaposiform lymphangiomatosis relieved by splenectomy.

Introduction: Kaposiform lymphangiomatosis (KLA) is a rare and complex lymphatic anomaly with a poor prognosis. There is no standard treatment, and drug therapies are the most common therapeutic method. However, some patients' symptoms become gradually aggravated despite medical treatment. Splenectomy may be an alternative option when pharmacological therapies are ineffective. Materials and Methods: We reviewed and evaluated the cases of 3 patients with KLA who ultimately underwent splenectomy. Results: The lesions were diffusely distributed and involved the lungs and spleens of the 3 patients. Laboratory examinations revealed that all three patients had thrombocytopenia and reduced fibrinogen levels. All patients underwent symptomatic splenectomy after the medication failed. Surprisingly, their symptoms greatly improved. Histopathological investigation of the splenic lesions of the three patients confirmed the diagnosis of KLA. Immunohistochemical staining showed positivity for CD31, CD34, podoplanin, Prox-1 and angiopoietin 2 (Ang-2). Discussion: This study aimed to review the features of KLA patients treated by splenectomy and explore the underlying link between splenectomy and prognosis. The reason for the improvement after splenectomy may be related to increased Ang-2 levels and platelet activation in patients with KLA. Future research should seek to develop more targeted drugs based on molecular findings, which may give new hope for the treatment of KLA.

Examining the expression and correlation of trip13 and angpt1 in small cell lung cancer: a professional exploration with an analogy to football players

This professional exploration delves into the intricate realm of thyroid hormone receptor interactor 13 (TRIP13) and angiopoietin-1 (ANGPT1) within the context of small cell lung cancer (SCLC). Drawing parallels to the precision and teamwork exemplified by football players on the field, we meticulously investigate the expression patterns and correlations of these molecular players in the complex landscape of SCLC. Our study encompassed a cohort of 78 SCLC patients treated at our institution between January 2015 and April 2017. Through rigorous immunohistochemical staining, we scrutinized the expression profiles of TRIP13 and ANGPT1 within tumor tissues, seeking to unravel their associations with clinicopathological characteristics and progression-free survival. Noteworthy findings emerged from our analysis. We observed significantly elevated positive expression rates of TRIP13 in SCLC tissues with lower differentiation levels and liver metastases, highlighting the analogy to football players' precise maneuvers. Similarly, ANGPT1 exhibited markedly increased positive expression rates in cases with larger tumor diameters, lower differentiation, and liver metastases, akin to a coordinated football team's collective effort. Our professional exploration uncovered a compelling positive correlation between the expression levels of TRIP13 and ANGPT1 in SCLC, akin to the synergy seen among football players on the field. This molecular partnership shed light on an intriguing aspect of SCLC's pathophysiology. The impact on progression-free survival time further emphasized the clinical relevance of TRIP13 and ANGPT1 in SCLC. Patients expressing both TRIP13 and ANGPT1 or either molecule alone experienced significantly shorter mean progression-free survival times, akin to the swift tactics and strategies employed by football players in a high-stakes game. (AU)

Early therapeutic effects of an Angiopoietin-1 mimetic peptide in middle-aged rats with vascular dementia.

Background: Vascular Dementia (VaD) refers to dementia caused by cerebrovascular disease and/or reduced blood flow to the brain and is the second most common form of dementia after Alzheimer's disease. We previously found that in middle-aged rats subjected to a multiple microinfarction (MMI) model of VaD, treatment with AV-001, a Tie2 receptor agonist, significantly improves short-term memory, long-term memory, as well as improves preference for social novelty compared to control MMI rats. In this study, we tested the early therapeutic effects of AV-001 on inflammation and glymphatic function in rats subjected to VaD. Methods: Male, middle-aged Wistar rats (10-12 m), subjected to MMI, were randomly assigned to MMI and MMI + AV-001 treatment groups. A sham group was included as reference group. MMI was induced by injecting 800 ± 200, 70-100 µm sized, cholesterol crystals into the internal carotid artery. Animals were treated with AV-001 (1 µg/Kg, i.p.) once daily starting at 24 h after MMI. At 14 days after MMI, inflammatory factor expression was evaluated in cerebrospinal fluid (CSF) and brain. Immunostaining was used to evaluate white matter integrity, perivascular space (PVS) and perivascular Aquaporin-4 (AQP4) expression in the brain. An additional set of rats were prepared to test glymphatic function. At 14 days after MMI, 50 µL of 1% Tetramethylrhodamine (3 kD) and FITC conjugated dextran (500 kD) at 1:1 ratio were injected into the CSF. Rats (4-6/group/time point) were sacrificed at 30 min, 3 h, and 6 h from the start of tracer infusion, and brain coronal sections were imaged using a Laser scanning confocal microscope to evaluate tracer intensities in the brain. Result: Treatment of MMI with AV-001 significantly improves white matter integrity in the corpus callosum at 14 days after MMI. MMI induces significant dilation of the PVS, reduces AQP4 expression and impairs glymphatic function compared to Sham rats. AV-001 treatment significantly reduces PVS, increases perivascular AQP4 expression and improves glymphatic function compared to MMI rats. MMI significantly increases, while AV-001 significantly decreases the expression of inflammatory factors (tumor necrosis factor-α (TNF-α), chemokine ligand 9) and anti-angiogenic factors (endostatin, plasminogen activator inhibitor-1, P-selectin) in CSF. MMI significantly increases, while AV-001 significantly reduces brain tissue expression of endostatin, thrombin, TNF-α, PAI-1, CXCL9, and interleukin-6 (IL-6). Conclusion: AV-001 treatment of MMI significantly reduces PVS dilation and increases perivascular AQP4 expression which may contribute to improved glymphatic function compared to MMI rats. AV-001 treatment significantly reduces inflammatory factor expression in the CSF and brain which may contribute to AV-001 treatment induced improvement in white matter integrity and cognitive function.

The Angiopoietin-2/Angiopoietin-1 ratio increases early in burn patients and predicts mortality.

BACKGROUND: Angiopoietin-2 (Angpt-2) is involved in the pathogenesis of the capillary leak syndrome in sepsis and has been shown to be associated with worse outcomes in diverse critical illnesses. It is however unclear whether Angpt-2 plays a similar role in severely burned patients during the early phase characterized by massive capillary leakage. Our aim was to analyze the Angiopoietin-2/Angiopoietin-1 ratio (Angpt-2/Angpt-1 ratio) over the first two days in critically ill burn patients and examine its association with survival and further clinical parameters. METHODS: Adult burn patients with a total burn surface area (TBSA) ≥ 20% treated in the burn intensive care unit (ICU) of the University Hospital of Zurich, Switzerland, were included. Serum samples were collected prospectively and serum Angpt-1 and Angpt-2 were measured by enzyme-linked immunosorbent assay (ELISA) over the first two days after burn insult and stratified according to survival status, TBSA and the abbreviated burn severity index (ABSI). Due to hemodilution in the initial resuscitation phase, the Angpt-2/Angpt-1 ratio was normalized to albumin. RESULTS: Fifty-six patients were included with a median age of 51.5 years. Overall mortality was 14.3% (8/56 patients). The total amount of infused crystalloids was 12́902 ml (IQR 9́362-16́770 ml) at 24 h and 18́461 ml (IQR 13́024-23́766 ml) at 48 h. The amount of substituted albumin was 20 g (IQR 10-50 g) at 24 h and 50 g (IQR 20-60 g) at 48 h. The albumin-corrected Angpt-2/Angpt-1 ratios increased over the first 48 h after the burn insult (d0: 0.5 pg*l/ml*g [IQR 0.24 - 0.80 pg*l/ml*g]; d1: 0.83 pg*l/ml*g [IQR 0.29 - 1.98 pg*l/ml*g]; d2: 1.76 pg*l/ml*g [IQR 0.70 - 3.23 pg*l/ml*g]; p < 0.001) and were significantly higher in eventual ICU non-survivors (p = 0.005), in patients with a higher TBSA (p = 0.001) and in patients with a higher ABSI (p = 0.001). CONCLUSIONS: In analogy to the pathological host response in sepsis, the Angpt-2/Angpt-1 ratio steadily increases in the first two days in critically ill burn patients, suggesting a putative involvement in the pathogenesis of capillary leakage in burns. A higher Angpt-2/Angpt-1 ratio is associated with mortality, total burn surface area and burn scores.

Targeted long-term noninvasive treatment of choroidal neovascularization by biodegradable nanoparticles.

Choroidal neovascularization (CNV) is the main cause of vision loss in patients with wet age-related macular degeneration (AMD). Currently, treatment of these conditions requires repeated intravitreal injections, which may lead to complications such as infection and hemorrhage. So, we have developed a noninvasive method for treating CNV with nanoparticles, namely, Angiopoietin1-anti CD105-PLGA nanoparticles (AAP NPs), which targets the CNV to enhance drug accumulation at the site. These nanoparticles, with PLGA as a carrier, can slowly release encapsulated Angiopoietin 1 (Ang 1) and target the choroidal neovascularization marker CD105 to enhance drug accumulation, increases vascular endothelial cadherin (VE-cadherin) expression between vascular endothelial cells, effectively reduce neovascularization leakage and inhibit Angiopoietin 2(Ang 2) secretion by endothelial cells. In a rat model of laser-induced CNV, intravenous injection of AAP NPs exerted a good therapeutic effect in reducing CNV leakage and area. In short, these synthetic AAP NPs provide an effective alternative treatment for AMD and meet the urgent need for noninvasive treatment in neovascular ophthalmopathy. STATEMENT OF SIGNIFICANCE: This work describes the synthesis, injection-mediated delivery, in vitro and in vivo efficacy of targeted nanoparticles with encapsulated Ang1; via these nanoparticles, the drug can be targeted to choroidal neovascularization lesions for continuous treatment. The release of Ang1 can effectively reduce neovascularization leakage, maintain vascular stability, and inhibit Ang2 secretion and inflammation. This study provides a new approach for the treatment of wet age-related macular degeneration.

Angiopoietin-1 promotes triple-negative breast cancer cell proliferation by upregulating carboxypeptidase A4.

Angiopoietin-1 (ANG1) is a pro-angiogenic regulator that contributes to the progression of solid tumors by stimulating the proliferation, migration and tube formation of vascular endothelial cells, as well as the renewal and stability of blood vessels. However, the functions and mechanisms of ANG1 in triple-negative breast cancer (TNBC) are unclear. The clinical sample database shows that a higher level of ANG1 in TNBC is associated with poor prognosis compared to non-TNBC. In addition, knockdown of ANG1 inhibits TNBC cell proliferation and induces cell cycle G1 phase arrest and apoptosis. Overexpression of ANG1 promotes tumor growth in nude mice. Mechanistically, ANG1 promotes TNBC by upregulating carboxypeptidase A4 (CPA4) expression. Overall, the ANG1-CPA4 axis can be a therapeutic target for TNBC.

Histological evaluation of the effects of bone morphogenetic protein 9 and angiopoietin 1 on bone healing.

Objectives: Bone healing remains a critical clinical orthopedic problem. Bone, which is a greatly vascularized tissue, depends on the tight temporal and spatial link between blood vessels and bone cells. Thus, angiogenesis is crucial for skeletal growth and bone fracture healing. The purpose of this study was to evaluate the efficacy of the local application of osteogenic and angiogenic factors such as bone morphogenetic protein 9 (BMP9) and angiopoietin 1 (Ang1), respectively, and their combination as an osteoinducer in the process of bone healing. Methods: Forty-eight male albino rats, weighing 300-400 g and aged 6-8 months, were utilized in this study. The animals underwent surgery on the medial side of the tibia bone. In the control group, an absorbable hemostatic sponge was locally applied to the bone defect, while experimental groups were separated into three groups. In Group I, 1 mg BMP9 was locally applied, Group II was treated with 1 mg Ang1, and Group III was treated with local application of a combination (0.5 mg BMP9 and 0.5 mg Ang1). All experimental groups were fixed with an absorbable hemostatic sponge. The rats were sacrificed on days 14 and 28 after surgery. Results: Local application of BMP9 alone, Ang1 alone, and their combination to a tibia defect caused osteoid tissue formation and significantly increased the number of bone cells. A gradual decrease in the number of trabecular bone, an increase in trabecular area, and no significant difference in the bone marrow area were noted. Conclusion: The combination of BMP9 and Ang1 has therapeutic potential in promoting the healing process of bone defects. Osteogenesis and angiogenesis are regulated by BMP9 and Ang1. These factors act together to accelerate bone regeneration more efficiently than either factor alone.

Reduced Angiopoietin Factor 2 Levels Are Correlated with Better Cardiac Function and Prognosis in Valvular Heart Disease

ABSTRACT Introduction: There are few circulating biomarkers for valvular heart disease. Angiopoietin (Ang) 1, Ang2, and vascular endothelial growth factor are important inflammation-associated cytokines. The aim of this study was to investigate the clinical significance and association of Ang1, Ang2, and vascular endothelial growth factor in valvular heart disease. Methods: This is a retrospective study; a total of 62 individuals (valvular heart disease patients [n=42] and healthy controls [n=20]) were included. Plasma levels of Ang1, Ang2, and vascular endothelial growth factor were detected by enzyme-linked immunosorbent assays. We retrospectively collected the baseline characteristics and short-term outcomes; logistic regression was performed to identify predictor for short-term mortality. Results: Ang2 was significantly decreased in the valvular heart disease group compared with the healthy control group (P=0.023), while no significant difference was observed in the Ang1 and vascular endothelial growth factor levels. The Ang2 level of New York Heart Association (NYHA) I/II patients — but not NYHA III/IV patients — was significantly decreased compared with that of healthy control individuals (NYHA I/II: P=0.017; NYHA III/IV: P=0.485). Univariable logistic regression analysis indicated that Ang2 was a significant independent predictor for short-term mortality (odds ratio 18.75, P=0.033, 95% confidence interval 8.08-102.33). Ang1 was negatively correlated with Ang2 (P=0.032, Pearson's correlation coefficient =-0.317) and was positively correlated with vascular endothelial growth factor (P=0.019, Pearson's correlation coefficient = 0.359). Conclusion: Ang2 might serve as a therapeutic and prognostic target for valvular heart disease.

Ang-1 Inhibited Endoplasmic Reticulum Stress and Apoptosis of VECs in Rats with aSAH-induced CVS Through the Regulated PI3K/Akt Pathway.

AIMS: To explore angiopoietin-1 (Ang-1) involved in cerebral vasospasm (CVS) after aneurysmal subarachnoid hemorrhage (aSAH) through its effect on endoplasmic reticulum stress (ERS) and apoptosis of vascular endothelial cells (VECs). BACKGROUND: CVS accounts for high morbidity and mortality of aSAH. Abnormal cellular physiological processes of VECs play a critical role in aSAH-induced CVS. In addition, Ang-1 is involved in regulating vascular structure and function. OBJECTIVE: To study the role of Ang-1 played in CVS and the underlying mechanism. METHODS: Blood samples of 130 aSAH patients were collected from 2016 to 2020 at West China Hospital of Sichuan University. A two-hemorrhage rodent model was employed to structure an aSAH-induced CVS rat model. Moreover, oxyHb was used to treat VECs to construct a CVS cell model in vitro. ELISA was used to measure the level of Ang-1 and HE staining to assess the rat's basilar arteries. Subsequently, CCK-8 was used to detect cell viability ability, and flow cytometry was used to test the cell apoptosis rate. Western blotting was used to determine the expression level of ERS marker and apoptosis-related proteins. RESULTS: There was an abnormally low expression of Ang-1 in CVS patients and CVS rats; besides, oxyHb treatment decreased Ang-1 in VECs in a concentration-dependent manner. Ang-1 treatment led to the thinner basilar artery wall and lumen circumference in CVS rats; moreover, in oxyHbtreated VECs, Ang-1 treatment inhibited ERS and apoptosis. In addition, the expression of p-PI3K and p-Akt in the CVS group decreased, while the expression of p53 in the CVS group increased. The expression of p-PI3K and p-Akt in 8 CVS rats negatively correlates with the expression of Ang- 1, but the correlation between p53 and Ang-1 was positive. Furthermore, the results suggested that Ang-1 suppressed ERS and apoptosis of VECs through the regulated PI3K/Akt/p53 pathway. CONCLUSION: Elevated Ang-1 inhibited p53-mediated ERS and apoptosis of VECs through the activated PI3K/Akt pathway; Ang-1 might be an attractive treatment strategy for CVS.

Reduced Angiopoietin Factor 2 Levels Are Correlated with Better Cardiac Function and Prognosis in Valvular Heart Disease.

INTRODUCTION: There are few circulating biomarkers for valvular heart disease. Angiopoietin (Ang) 1, Ang2, and vascular endothelial growth factor are important inflammation-associated cytokines. The aim of this study was to investigate the clinical significance and association of Ang1, Ang2, and vascular endothelial growth factor in valvular heart disease. METHODS: This is a retrospective study; a total of 62 individuals (valvular heart disease patients [n=42] and healthy controls [n=20]) were included. Plasma levels of Ang1, Ang2, and vascular endothelial growth factor were detected by enzyme-linked immunosorbent assays. We retrospectively collected the baseline characteristics and short-term outcomes; logistic regression was performed to identify predictor for short-term mortality. RESULTS: Ang2 was significantly decreased in the valvular heart disease group compared with the healthy control group (P=0.023), while no significant difference was observed in the Ang1 and vascular endothelial growth factor levels. The Ang2 level of New York Heart Association (NYHA) I/II patients - but not NYHA III/IV patients - was significantly decreased compared with that of healthy control individuals (NYHA I/II: P=0.017; NYHA III/IV: P=0.485). Univariable logistic regression analysis indicated that Ang2 was a significant independent predictor for short-term mortality (odds ratio 18.75, P=0.033, 95% confidence interval 8.08-102.33). Ang1 was negatively correlated with Ang2 (P=0.032, Pearson's correlation coefficient =-0.317) and was positively correlated with vascular endothelial growth factor (P=0.019, Pearson's correlation coefficient = 0.359). CONCLUSION: Ang2 might serve as a therapeutic and prognostic target for valvular heart disease.

Serum Ang-1/Ang-2 ratio may be a promising biomarker for evaluating severity of diabetic retinopathy.

PURPOSE: To investigate the predictive role of serum angiopoietin-1 and angiopoietin-2 (Ang-1/Ang-2) in evaluating the severity of diabetic retinopathy (DR). METHODS: A total of 101 outpatients with type 2 diabetes mellitus (T2DM) were recruited and were further divided into the following five groups: T2DM without DR (non-DR), mild non-proliferative DR (NPDR), moderate NPDR, severe NPDR and proliferative DR (PDR) in accordance with the International Clinical Diabetic Retinopathy Guidelines. Furthermore, 101 serum samples were included in the further analysis using enzyme-linked immunosorbent assays. A receiver operating characteristic (ROC) curve was plotted to evaluate the diagnostic value of each index. RESULTS: The expression of Ang-1 in the PDR group was significantly lower than that in the non-DR group, while Ang-2 showed an opposite upward trend (p < 0.05). The Ang-1/Ang-2 ratio of the non-DR group was significantly lower than that of the moderate NPDR, severe NPDR and PDR (p < 0.05, p < 0.01 and p < 0.01, respectively). Differences in the Ang-1/Ang-2 ratio were observed earlier than those in the individual Ang-1 and Ang-2 measurements. The maximal Youden index was 0.512 with a calculated area under the curve (AUC) value of 0.734 (p < 0.01). CONCLUSIONS: The Ang-1/Ang-2 ratio was helpful in assessing the severity of DR and may provide potential clinical benefits as a biomarker and early warning signs for DR diagnosis.

The relationship between angiopoietin 1 and Smadhomolog 9 gene expression in cancer tissues and tumor metastasis, invasion behavior and prognosis in patients with lung adenocarcinoma / 中国医师进修杂志

Objective:To explore the relationship between the expression of angiopoietin 1 (ANGPT1) and Smadhomolog 9 (Smad9) genes in cancer tissues and tumor metastasis, invasion behavior and prognosis in patients with lung adenocarcinoma.Methods:Sixty patients with lung adenocarcinoma in Chengwu Hospital Affiliated to Shandong First Medical University from October 2018 to December 2019 were selected as the research objects. The expressions of ANGPT1 and Smad9 mRNA in cancer tissues and adjacent tissues were compared, as well as the expressions of ANGPT1 and Smad9 mRNA in cancer tissues of patients with different tumor metastasis and invasion behaviors. The relationship between ANGPT1 and Smad9 mRNA expression and tumor metastasis and invasion behavior of lung adenocarcinoma were analyzed, and the 1-year survival rate of patients with lung adenocarcinoma was calculated. The 1-year survival rate of patients with different ANGPT1 and SMAD9 mRNA expression levels were compared.Results:The relative expression of ANGPT1 mRNA and Smad9 mRNA in cancer tissues were lower than those in adjacent tissues: 2.45 ± 0.26 vs. 11.18 ± 0.93, 4.23 ± 0.31 vs. 7.58 ± 0.65, the differences were statistically significant ( P<0.05). There were significant differences in the relative gene expression of ANGPT1 and Smad9 mRNA in different clinical stages, tumor diameter, degree of differentiation, lymph node metastasis and pleural invasion ( P<0.05). Spearman correlation analysis showed that the expression of ANGPT1 and Smad9 mRNA were negatively correlated with clinical stage, tumor diameter, lymph node metastasis and pleural invasion ( r = - 0.517, - 0.539, - 0.606, - 0.679, P<0.05), and positively correlated with the degree of differentiation ( r = 0.628, P<0.05). The 1-year survival rate of 58 patients was 72.41%. Kaplan-Meier curve analysis showed that the 1-year survival rate of patients with low expression of ANGPT1 and Smad9 mRNA in cancer tissues were were lower than those in patients with high expression ( P<0.05). Conclusions:Down-regulation of ANGPT1 and Smad9 genes in cancer tissues will accelerate the metastasis and invasion behavior of lung adenocarcinoma. Up-regulating the expression of both genes can be a potential way to improve survival.

Irisin promotes fracture healing by improving osteogenesis and angiogenesis.

Background: Osteogenesis and angiogenesis are important for bone fracture healing. Irisin is a muscle-derived monokine that is associated with bone formation. Methods: To demonstrate the effect of irisin on bone fracture healing, closed mid-diaphyseal femur fractures were produced in 8-week-old C57BL/6 mice. Irisin was administrated intraperitoneally every other day after surgery, fracture healing was assessed by using X-rays. Bone morphometry of the fracture callus were assessed by using micro-computed tomography. Femurs of mice from each group were assessed by the three-point bending testing. Effect of irisin on osteogenic differentiation in mesenchymal stem cells in vitro was evaluated by quantitative real-time polymerase chain reaction (qRT-PCR), alkaline phosphatase staining and alizarin red staining. Angiogenesis of human umbilical vein endothelial cells (HUVECs) were evaluated by qRT-PCR, migration tests, and tube formation assays. Results: Increased callus formation, mineralization and tougher fracture healing were observed in the irisin-treated group than in the control group, indicating the better fracture callus healing due to Irisin treatment. The vessel surface and vessel volume fraction of the callus also increased in the irisin-treated group. The expression of BMP2, CD31, and VEGF in callus were enhanced in the irisin-treated group. In mouse bone mesenchymal stem cells, irisin promoted ALP expression and mineralization, and increased the expression of osteogenic genes, including OSX, Runx2, OPG, ALP, OCN and BMP2. Irisin also promoted HUVEC migration and tube formation. Expression of angiogenic genes, including ANGPT1, ANGPT2, VEGFb, CD31, FGF2, and PDGFRB in HUVECs were increased by irisin. Conclusion: All the results indicate irisin can promote fracture healing through osteogenesis and angiogenesis. These findings help in the understanding of muscle-bone interactions during fracture healing. The Translational Potential of this Article: Irisin was one of the most important monokine secreted by skeletal muscle. Studies have found that irisin have anabolic effect one bone remodeling through affecting osteocyte and osteoblast. Based on our study, irisin could promote bone fracture healing by increasing bone mass and vascularization, which provide a potential usage of irisin to promote fracture healing and improve clinical outcomes.