Angiopoietin-like Protein Research Articles

Precision medicine in diabetes prediction: Exploring a subgroup-specific biomarker strategy for risk stratification.

The early detection of high-risk individuals is crucial to delay and reduce the incidence of type 2 diabetes. In this study, we aimed to explore the performance of a novel subgroup-specific biomarker strategy in the prediction of incident diabetes. In the Taiwan Lifestyle Cohort Study, adult subjects without diabetes were included and followed for the incidence of diabetes in 2006-2019. The biomarkers measured included blood secretogranin III (SCG3), vascular adhesion protein-1 (VAP-1), fibrinogen-like protein 1 (FGL1), angiopoietin-like protein 6 (ANGPTL6), and angiopoietin-like protein 4 (ANGPTL4). Among the 1,287 subjects, 12.2% developed diabetes during a 6 year follow-up. Blood VAP-1 was significantly associated with incident diabetes in the overall population (HR = 0.724, P < 0.05), participants under 65 years old (HR = 0.685, P < 0.05), those with a BMI of ≥24 kg/m2 (HR = 0.673, P < 0.05), and females (HR = 0.635, P < 0.05). Blood ANGPTL6 was significantly correlated with incident diabetes in participants aged 65 and older (HR = 0.314, P < 0.05), and blood SCG3 was associated with incident diabetes in those with a BMI of <24 kg/m2 (HR = 1.296, P < 0.05). Two subgroup-specific biomarker strategies were developed. The gender and BMI-specific biomarker strategy, using traditional risk factors and blood SCG3 or VAP-1 in different subgroups, could improve prediction performance, especially the specificity and positive prediction value, compared with the whole-population strategy using only traditional risk factors or traditional risk factors plus blood VAP-1. Gender- and BMI-specific biomarker strategy can improve the prediction of incident diabetes. A subgroup-specific biomarker strategy is a novel approach in the prediction of incident diabetes.

Adipokine/hepatokines profiling of fatty liver in adolescents and young adults: cross-sectional and prospective analyses of the BCAMS study.

The underlying connections between obesity and non-alcoholic fatty liver disease (NAFLD) are not fully understood. One potential link might be the imbalanced adipokines and hepatokines. We aimed to explore the associations between specific adipokines/hepatokines and NAFLD in Chinese youth and to determine how these biomarkers mediate the obesity-NAFLD relationship. We analyzed data from the 10-year follow-up visit of the Beijing Children and Adolescents Metabolic Syndrome (BCAMS) study (n = 509; mean age = 20.2years) for a comprehensive metabolic risk assessment, including liver ultrasound and plasma measurements of adiponectin, leptin, fibroblast growth factor 21 (FGF21), retinol-binding protein 4 (RBP4), and angiopoietin-like protein 8 (ANGPTL8). Longitudinal analysis was performed on a subgroup (n = 307), with complete baseline (mean age = 12.2years) and follow-up data. Mediation models assessed how obesity at baseline and follow-up influence NAFLD through these biomarkers. Participants with NAFLD exhibited a high prevalence of central obesity (90.9%). Both cross-sectional and prospective analyses identified increased RBP4, FGF21, leptin, and decreased adiponectin levels as significant predictors of NAFLD. More adipokine/hepatokine abnormalities were linked to higher NAFLD risk. Furthermore, ratios reflecting adipokine/hepatokine imbalances, including leptin/adiponectin, FGF21/adiponectin, and RBP4/adiponectin, demonstrated stepwise changes correlating with NAFLD severity (all p < 0.05). Mediation analysis indicated that these four adipokines/hepatokines accounted for approximately 72.4% of the central obesity-NAFLD relationship and 80.1% in the subgroup analysis using baseline childhood data. Dysregulated adipokines/hepatokines may explain the onset or progression of obesity-related NAFLD in youths. Higher RBP4, FGF21 and leptin, alongside lower adiponectin, could serve as early biomarkers for NAFLD.

ASGR1 Deficiency Inhibits Atherosclerosis in Western Diet-Fed ApoE-/- Mice by Regulating Lipoprotein Metabolism and Promoting Cholesterol Efflux.

Atherosclerosis is the most common cause of cardiovascular diseases. Clinical studies indicate that loss-of-function ASGR1 (asialoglycoprotein receptor 1) is significantly associated with lower plasma cholesterol levels and reduces cardiovascular disease risk. However, the effect of ASGR1 on atherosclerosis remains incompletely understood; whether inhibition of ASGR1 causes liver injury remains controversial. Here, we comprehensively investigated the effects and the underlying molecular mechanisms of ASGR1 deficiency and overexpression on atherosclerosis and liver injury in mice. We engineered Asgr1 knockout mice (Asgr1-/-), Asgr1 and ApoE double-knockout mice (Asgr1-/-ApoE-/-), and ASGR1-overexpressing mice on an ApoE-/- background and then fed them different diets to assess the role of ASGR1 in atherosclerosis and liver injury. After being fed a Western diet for 12 weeks, Asgr1-/-ApoE-/- mice exhibited significantly decreased atherosclerotic lesion areas in the aorta and aortic root sections, reduced plasma VLDL (very-low-density lipoprotein) cholesterol and LDL (low-density lipoprotein) cholesterol levels, decreased VLDL production, and increased fecal cholesterol contents. Conversely, ASGR1 overexpression in ApoE-/- mice increased atherosclerotic lesions in the aorta and aortic root sections, augmented plasma VLDL cholesterol and LDL cholesterol levels and VLDL production, and decreased fecal cholesterol contents. Mechanistically, ASGR1 deficiency reduced VLDL production by inhibiting the expression of MTTP (microsomal triglyceride transfer protein) and ANGPTL3 (angiopoietin-like protein 3)/ANGPTL8 (angiopoietin-like protein 8) but increasing LPL (lipoprotein lipase) activity, increased LDL uptake by increasing LDLR (LDL receptor) expression, and promoted cholesterol efflux through increasing expression of LXRα (liver X receptor-α), ABCA1 (ATP-binding cassette subfamily A member 1), ABCG5 (ATP-binding cassette subfamily G member 5), and CYP7A1 (cytochrome P450 family 7 subfamily A member 1). These underlying alterations were confirmed in ASGR1-overexpressing ApoE-/- mice. In addition, ASGR1 deficiency exacerbated liver injury in Western diet-induced Asgr1-/-ApoE-/- mice and high-fat diet-induced but not normal laboratory diet-induced and high-fat and high-cholesterol diet-induced Asgr1-/- mice, while its overexpression mitigated liver injury in Western diet-induced ASGR1-overexpressing ApoE-/- mice. Inhibition of ASGR1 inhibits atherosclerosis in Western diet-fed ApoE-/- mice, suggesting that inhibiting ASGR1 may serve as a novel therapeutic strategy to treat atherosclerosis and cardiovascular diseases.

ANGPTL4 plays a paradoxical role in gastric cancer through the LGALS7 and Hedgehog pathways.

Gastric cancer (GC) is a malignant disease worldwide. Angiopoietin-like protein 4 (ANGPTL4) plays a role in pathophysiological processes, including metabolic reprogramming, angiogenesis, proliferation, and metastasis. Current evidence shows conflicting findings regarding the role of ANGPTL4 in the progression of GC. ANGPTL4 in GC was confirmed through bioinformatic analysis and immunofluorescence staining. The impact of ANGPTL4 was subsequently validated in GC cell lines using various assays, including 5-ethynyl-2-deoxyuridine (EdU), 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), Flow Cytometry (FCM), wound healing, transwell, tube formation, chorioallantoic membrane model, and nude mouse model assays. RNA-seq analysis, polymerase chain reaction (PCR), western blotting (WB), immunofluorescence (IF) and coimmunoprecipitation (co-IP) were conducted to determine the potential downstream mechanism of ANGPTL4. In SNU5 and MKN7 cells, ANGPTL4 was found to augment proliferation, migration, invasion, evasion of apoptosis, and angiogenesis. Conversely, in the AGS cell line, ANGPTL4 was observed to suppress these processes. Notably, the overexpression of ANGPTL4 in AGS cells led to the upregulation of LGALS7, which has emerged as a pivotal factor contributing to the manifestation of an anticancer phenotype induced by ANGPTL4. LGALS7, which is involved in the regulation of the hedgehog pathway and subsequent promotion of GC progression through various processes, such as proliferation, migration, apoptosis evasion, angiogenesis, and lymphangiogenesis, was found to contribute to the contradictory effects of ANGPTL4.

Host ANGPTL2 establishes an immunosuppressive tumor microenvironment and resistance to immune checkpoint therapy.

Use of immune checkpoint inhibitors (ICIs) as cancer immunotherapy has advanced rapidly in the clinic; however, mechanisms underlying resistance to ICI therapy, including impaired T cell infiltration, low immunogenicity, and tumor "immunophenotypes" governed by the host, remain unclear. We previously reported that in some cancer contexts, tumor cell-derived angiopoietin-like protein 2 (ANGPTL2) has tumor-promoting functions. Here, we asked whether ANGPTL2 deficiency could enhance antitumor ICI activity in two inflammatory contexts: a murine syngeneic model of colorectal cancer and a mouse model of high-fat diet (HFD)-induced obesity. Systemic ANGPTL2 deficiency potentiated ICI efficacy in the syngeneic model, supporting an immunosuppressive role for host ANGPTL2. Relevant to the mechanism, we found that ANGPTL2 induces pro-inflammatory cytokine production in adipose tissues, driving generation of myeloid-derived suppressor cells (MDSCs) in bone marrow and contributing to an immunosuppressive tumor microenvironment and resistance to ICI therapy. Moreover, HFD-induced obese mice showed impaired responsiveness to ICI treatment, suggesting that obesity-induced chronic inflammation facilitated by high ANGPTL2 expression blocks ICI antitumor effects. Our findings overall provide novel insight into protumor ANGPTL2 functions and illustrate the essential role of the host system in ICI responsiveness.

NCK-associated protein 1 (NCKAP1) And Angiopoietin-like protein 1 (ANGPTL1): A novel prognostic markers and promising therapeutic target for colorectal carcinoma patients

NCK-associated protein 1 (NCKAP1) And Angiopoietin-like protein 1 (ANGPTL1): A novel prognostic markers and promising therapeutic target for colorectal carcinoma patients

Exploring the Association of VEGF-A and ANGPTL2 with the Prognosis of Non-proliferative and Proliferative Diabetic Retinopathy.

Introduction Diabetic retinopathy (DR) is a microvascular ailment that can arise from the long-term effects of diabetes mellitus. It can potentially cause retinal damage that could endanger vision and cause blindness. The worsening of DR is mainly linked to poor glycemic control, uncontrolled hypertension, and dyslipidemia. There is a need for alternative and clinically significant novel molecules involved in the pathogenesis of DR because the diagnostic and prognostic markers have reached a limit. Materials and method This study included sex and age-matched diabetic patients with proliferative stage (N = 70), non-proliferative stage (N = 80), and control (N = 80, without the sign of DR). These patients were recruited from outpatients in the Department of Ophthalmology, Sri Ramachandra Institute of Higher Education and Research, Chennai, India. A random blood sample was collected from each study participant, and the serum was separated after centrifugation and stored at -80 °C for batch analysis. The biomarkers vascular endothelial growth factor (VEGF-A) and angiopoietin-like protein-2 (ANGPTL2) were measured using a sandwich enzyme-linked immunosorbent assay (ELISA) technique, and the laboratory parameters such as fasting blood sugar (FBS), lipid profile, blood urea nitrogen (BUN), creatine, and glycated hemoglobin (HbA1C) were also assessed. Results We observed statistically significant differences in theduration of diabetes, FBS, total cholesterol (TC), triglyceride level (TGL), BUN, and creatine (p<0.05), and the mean age of study participants was 52.95±8.20 years in the control group, 53.85±10.20 years in the proliferative diabetic retinopathy (PDR) group, and 55.02±7.65 in the non-proliferative diabetic retinopathy (NPDR) group. Furthermore, ANGPTL2 levels were statistically significant according to the severity of the disease (p<0.001*), and they were also linked (p<0.05) with established markers such as VEGF-A. Conclusion Thus, our research implies that the up-regulated markers might be linked to the disease's advancement and could serve as a prognostic indicator or therapeutic target for DR.

Endothelial lipase and its endogenous inhibitor angiopoietin-like protein 3 regulate the transport of both low- and high- density lipoproteins by aortic endothelial cells

Endothelial lipase and its endogenous inhibitor angiopoietin-like protein 3 regulate the transport of both low- and high- density lipoproteins by aortic endothelial cells

Inhibition of ANGPTL8 protects against diabetes-associated cognitive dysfunction by reducing synaptic loss via the PirB signaling pathway

BackgroundType 2 diabetes mellitus (T2D) is associated with an increased risk of cognitive dysfunction. Angiopoietin-like protein 8 (ANGPTL8) is an important regulator in T2D, but the role of ANGPTL8 in diabetes-associated cognitive dysfunction remains unknown. Here, we explored the role of ANGPTL8 in diabetes-associated cognitive dysfunction through its interaction with paired immunoglobulin-like receptor B (PirB) in the central nervous system.MethodsThe levels of ANGPTL8 in type 2 diabetic patients with cognitive dysfunction and control individuals were measured. Mouse models of diabetes-associated cognitive dysfunction were constructed to investigate the role of ANGPTL8 in cognitive function. The cognitive function of the mice was assessed by the Barnes Maze test and the novel object recognition test, and levels of ANGPTL8, synaptic and axonal markers, and pro-inflammatory cytokines were measured. Primary neurons and microglia were treated with recombinant ANGPTL8 protein (rA8), and subsequent changes were examined. In addition, the changes induced by ANGPTL8 were validated after blocking PirB and its downstream pathways. Finally, mice with central nervous system-specific knockout of Angptl8 and PirB−/− mice were generated, and relevant in vivo experiments were performed.ResultsHere, we demonstrated that in the diabetic brain, ANGPTL8 was secreted by neurons into the hippocampus, resulting in neuroinflammation and impairment of synaptic plasticity. Moreover, neuron-specific Angptl8 knockout prevented diabetes-associated cognitive dysfunction and neuroinflammation. Mechanistically, ANGPTL8 acted in parallel to neurons and microglia via its receptor PirB, manifesting as downregulation of synaptic and axonal markers in neurons and upregulation of proinflammatory cytokine expression in microglia. In vivo, PirB−/− mice exhibited resistance to ANGPTL8-induced neuroinflammation and synaptic damage.ConclusionTaken together, our findings reveal the role of ANGPTL8 in the pathogenesis of diabetes-associated cognitive dysfunction and identify the ANGPTL8-PirB signaling pathway as a potential target for the management of this condition.

Abstract Tu015: Angiopoietin-like 4 Stabilizes Atherosclerotic Plaques by Modulating the Phenotypic Transition of Endothelial Cells and Vascular Smooth Muscle Cells

Atherosclerosis, the leading cause of death, is a vascular disease of chronic inflammation. We recently showed that angiopoietin-like 4 (ANGPTL4) promotes cardiac repair by suppressing pathological inflammation. Given the fundamental contribution of inflammation to atherosclerosis, we assessed the role of ANGPTL4 in the development of atherosclerosis and determined whether ANGPTL4 regulates atherosclerotic plaque stability. We injected ANGPTL4 protein twice a week into atherosclerotic Apoe-/- mice and analyzed the atherosclerotic lesion size, endothelial dysfunction, inflammation, and plaque stability. In atherosclerotic mice, ANGPTL4 reduced the atherosclerotic plaque size, endothelial dysfunction, and vascular inflammation. Furthermore, ANGPTL4 was associated with maintenance of vascular integrity and attenuated endothelial-to-mesenchymal transition (EndMT) in both HUVEC and atherosclerotic plaque of Apoe-/- mice. In the atherosclerotic lesions and fibrous caps, the number of α-SMA(+), SM22α(+), and SM-MHC(+) cells was higher, while the number of CD68(+) and Mac2(+) cells was lower in the ANGPTL4 group. Most importantly, the fibrous cap was significantly thicker in the ANGPTL4 group than in the PBS group. Smooth muscle cells (SMCs) isolated from atherosclerotic aortas showed significantly increased expression of CD68 and Krüppel-like factor 4 (KLF4), a modulator of the vascular SMC phenotype, along with downregulation of α-SMA, and these changes were attenuated by ANGPTL4 treatment. Furthermore, ANGPTL4 reduced TNFa-induced NADPH oxidase 1 (NOX1), a major source of reactive oxygen species, resulting in attenuation of KLF4-mediated SMC phenotypic changes. Our results reveal that ANGPTL4 treatment inhibits atherogenesis and suggest that targeting vascular stability and inflammation may serve as a novel therapeutic strategy to prevent and treat atherosclerosis. Even more importantly, ANGPTL4 treatment inhibited the phenotypic changes of SMCs into macrophage-like cells by downregulating NOX1 activation of KLF4, leading to the formation of more stable plaques.

Therapeutic Gene Editing in Dyslipidemias.

Dyslipidemia, characterized by abnormal lipid levels in the blood, significantly escalates the risk of atherosclerotic cardiovascular disease and requires effective treatment strategies. While existing therapies can be effective, long-term adherence is often challenging. There has been an interest in developing enduring and more efficient solutions. In this context, gene editing, particularly clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) technology, emerges as a groundbreaking approach, offering potential long-term control of dyslipidemia by directly modifying gene expression. This review delves into the mechanistic insights of various gene-editing tools. We comprehensively analyze various pre-clinical and clinical studies, evaluating the safety, efficacy, and therapeutic implications of gene editing in dyslipidemia management. Key genetic targets, such as low-density lipoprotein receptor (LDLR), proprotein convertase subtilisin/kexin type 9 (PCSK9), angiopoietin-like protein 3 (ANGPTL3), apolipoprotein C3 (APOC3), and lipoprotein (a) (Lp(a)), known for their pivotal roles in lipid metabolism, are scrutinized. The paper highlights the promising outcomes of gene editing in achieving sustained lipid homeostasis, discusses the challenges and ethical considerations in genome editing, and envisions the future of gene therapy in revolutionizing dyslipidemia treatment and cardiovascular risk reduction.

Periodontitis promotes hepatocellular carcinoma in Stelic Animal model (STAM) mice

Periodontitis is a prevalent oral inflammatory disease that leads to alveolar bone loss and may exert an adverse impact on systemic health. Periodontal disease may be associated with hepatocellular carcinoma (HCC); however, the mechanism of such an association is unknown. In this study, Stelic Animal model (STAM) mice, a model of nonalcoholic steatohepatitis (NASH)-HCC, were induced to develop periodontitis and subjected to histopathological and immunological analyses. HCC progression was greater in STAM mice with experimental periodontitis compared with that in STAM mice without experimental periodontitis. Tumor necrosis factor-α (TNFα), matrix metalloproteinase-9 (MMP9), collagen 1, and angiopoietin-like protein 2 (ANGPTL2) gene expression was significantly increased in the liver of the periodontitis group. ANGPTL2 was previously reported to be involved in the pathogenesis of periodontitis, and HCC and ANGPTL2 protein tended to be more abundant in the pocket epithelium of STAM mice with experimental periodontitis than in control STAM mice. ANGPTL2 levels in the serum of STAM mice with experimental periodontitis tended to be higher than in control STAM mice. Our results indicate that ANGPTL2 is produced in chronically inflamed periodontal tissue and then travels to the liver via the bloodstream where it accumulates to promote the progression of hepatocellular carcinoma.

Peculiarities of laboratory parameters dynamics during helicobacter pylori eradication in patients with rheumatoid arthritis

Helicobacter pylori (H. pylori) is able to participate in the pathogenesis of a number of autoimmune diseases, actively maintains chronic inflammation and stimulates the systemic immune response. The virulence factor of H. pylori is cytotoxin-associated gene A (CagA) is associated with more severe inflammatory reactions, increased risk of poor clinical outcomes and is able to influence the efficacy of infection eradication in patients with rheumatoid arthritis (RA).Purpose of the study. To evaluate laboratory parameters of H. pylori eradication efficacy in RA patients with chronic infection with the strain encoding cytotoxin-associated gene A.Materials and methods. Forty women with RA and confirmed chronic H. pylori infection were included in the study (mean age 55.5±8.7 years; mean disease duration 13.9±9.1 years; DAS-28–3.96±0.56). CagA-IgG associated H. pylori infection was diagnosed in 22 (group I, CagA+) and not diagnosed in 18 (group II, CagA-) patients. All RA patients underwent a course of H. pylori eradication therapy.Results. The process of H. pylori eradication had the most significant effect on laboratory parameters of CagA-negative RA patients (group II). In this group the levels of rheumatoid factor (p=0,028), C-reactive protein (CRP, p=0.001), interleukin-6 (IL-6, p=0.002), tumor necrosis factor alpha (p=0,023), angiopoietinlike protein type 3 (p=0.026) and antibodies to cyclic citrullinated peptide (ACCP, p=0,016) decreased significantly. In patients from group I (CagA+) most parameters remained practically unchanged (p&gt;0.05), except for CRP (p=0.01) and IL-6 (p=0.011). In the short term, the success of eradication in CagA+ patients was significantly lower than in CagA- patients (p=0.033). Moreover, confirmation of successful eradication of H. pylori within the established period of time was extremely rare (p=0.009) in the combination of CagA+ and high titers of ACCP and antibodies to modified citrullinated vimentin.Conclusions. The effectiveness of H. pylori eradication in RA patients depends on the presence of chronic infection with the strain encoding the cytotoxin-associated gene A and the level of antibodies to citrullinated proteins, which should be taken into account when choosing the therapeutic effect on H. pylori in this group.

ASO Visual Abstract: Angiopoietin-Like Protein 2 Expression in Tumor Cells Supports Tumor-Associated Macrophage-Induced Tumor Progression in Esophageal Cancer.

ASO Visual Abstract: Angiopoietin-Like Protein 2 Expression in Tumor Cells Supports Tumor-Associated Macrophage-Induced Tumor Progression in Esophageal Cancer.

Angiopoietin-Like Protein 2 Expression in Tumor Cells Supports Tumor-Associated Macrophage-Induced Tumor Progression in Esophageal Cancer.

Tumor-associated macrophages(TAM),a major component of the tumor microenvironment, play key roles in tumor formation and progression; however, mechanisms underlying TAM-induced tumor progression are complex and not well known. We previously reported that tumor cell-derived angiopoietin-like protein 2 (ANGPTL2) functions as a tumor promoter in some cancer contexts. We examined ANGPTL2 expression in paraffin-embedded tumor samples from resected specimens of 221 patients with esophageal cancer. Patients were subdivided into four groups based on immunohistochemistry scores described above: ANGPTL2-low/TAM-low, ANGPTL2-low/TAM-high, ANGPTL2-high/TAM-low, and ANGPTL2-high/TAM-high groups. Gene expression datasets of esophageal cancer cell lines were obtained from the cancer cell line encyclopedia public database. In this study, we demonstrate that TAM infiltration is associated with poor prognosis in patients with esophageal cancer whose tumor cells show relatively higher ANGPTL2 expression levels; however, TAM infiltration did not affect prognosis in patients with ANGPTL2-low-expressing esophageal cancer, suggesting that ANGPTL2 expression in esophageal cancer cells is required for TAM-induced tumor progression. Our analysis of public datasets indicates a potential positive correlation of ANGPTL2 expression levels with that of transforming growth factor (TGF)-β, a TAM-activating factor, in esophageal cancer cell lines. We conclude that ANGPTL2 signaling in tumor cells supports TAM-induced tumor progression and contributes to poor prognosis in patients with esophageal cancer. These findings overall provide novel insight into pro-tumor ANGPTL2 functions and illustrate the essential role of cancer cell/TAM crosstalk in cancer progression.

Leptin-mediated suppression of lipoprotein lipase cleavage enhances lipid uptake and facilitates lymph node metastasis in gastric cancer.

Lymph node metastasis (LNM) is the primary mode of metastasis in gastric cancer (GC). However, the precise mechanisms underlying this process remain elusive. Tumor cells necessitate lipid metabolic reprogramming to facilitate metastasis, yet the role of lipoprotein lipase (LPL), a pivotal enzyme involved in exogenous lipid uptake, remains uncertain in tumor metastasis. Therefore, the aim of this study was to investigate the presence of lipid metabolic reprogramming during LNM of GC as well as the role of LPL in this process. Intracellular lipid levels were quantified using oil red O staining, BODIPY 493/503 staining, and flow cytometry. Lipidomics analysis was employed to identify alterations in intracellular lipid composition following LPL knockdown. Protein expression levels were assessed through immunohistochemistry, Western blotting, and enzyme-linked immunosorbent assays. The mouse popliteal LNM model was utilized to investigate differences in LNM. Immunoprecipitation and mass spectrometry were employed to examine protein associations. In vitro phosphorylation assays and Phos-tag sodium dodecyl-sulfate polyacrylamide gel electrophoresis assays were conducted to detect angiopoietin-like protein 4 (ANGPTL4) phosphorylation. We identified that an elevated intracellular lipid level represents a crucial characteristic of node-positive (N+) GC and further demonstrated that a high-fat diet can expedite LNM. LPL was found to be significantly overexpressed in N+ GC tissues and shown to facilitate LNM by mediating dietary lipid uptake within GC cells. Leptin, an obesity-related hormone, intercepted the effect exerted by ANGPTL4/Furin on LPL cleavage. Circulating leptin binding to the leptin receptor could induce the activation of inositol-requiring enzyme-1 (IRE1) kinase, leading to the phosphorylation of ANGPTL4 at the serine 30 residue and subsequently reducing its binding affinity with LPL. Moreover, our research revealed that LPL disrupted lipid homeostasis by elevating intracellular levels of arachidonic acid, which then triggered the cyclooxygenase-2/prostaglandin E2 (PGE2) pathway, thereby promoting tumor lymphangiogenesis. Leptin-induced phosphorylation of ANGPTL4 facilitates LPL-mediated lipid uptake and consequently stimulates the production of PGE2, ultimately facilitating LNM in GC.

PM2.5 induces lung inflammation through ANGPTL4

Fine particulate matter (PM2.5) is a common major air pollutant and is associated with decreased lung function, induced allergic airway inflammation and is closely correlated with chronic lung diseases. Angiopoietin-like protein 4 (ANGPTL4) is a cytokine with multiple functions, participating in processes such as inflammation, angiogenesis, and metastasis. Curcumin is an active compound found in turmeric plants and possesses various pharmacological effects, including antioxidant, anti-inflammatory, anticancer, and immunomodulatory properties. The aim of this study was twofold: firstly, to investigate the involvement of ANGPTL4 in lung inflammation and carcinogenesis under PM2.5 exposure, and secondly, to explore the impact of curcumin on ANGPTL4 expression and its potential in lung cancer chemoprevention. We used protein array to detect severe proinflammatory cytokines and then used qPCR to confirm by increasing the concentration of PM2.5 to enhance the expressions of CXCL1, CXCL5; IL-1α, IL-1β, MIP-3α and inflammatory or fibrosis associated proteins. Curcumin inhibits PM2.5 induced ANGPTL4 and the IκB-α (inhibitor of NFκB) dependent inflammatory pathway. Silencing of ANGPTL4 by shRNA will restore IκB-α and MIP-3α expression. In conclusion, the increased expression of ANGPTL4 after treatment with PM2.5 in lung cells may be one of the mechanisms by which PM2.5 exposure contributes to lung inflammation progression and our results provide evidence that curcumin in anti-inflammation therapeutics could be a beneficial chemopreventive agent.

Angiopoietin-like protein 2 inhibits thrombus formation.

Acute myocardial infarction is mainly caused by a lack of blood flood in the coronary artery. Angiopoietin-like protein 2 (ANGPTL2) induces platelet activation and thrombus formation in vitro through binding with immunoglobulin-like receptor B, an immunoglobulin superfamily receptor. However, the mechanism by which it regulates platelet function in vivo remains unclear. In this study, we investigated the role of ANGPTL2 during thrombosis in relationship with ST-segment elevation myocardial infarction (STEMI) with spontaneous recanalization (SR). In a cohort of 276 male and female patients, we measured plasma ANGPTL2 protein levels. Using male Angptl2-knockout and wild-type mice, we examined the inhibitory effect of Angptl2 on thrombosis and platelet activation both in vivo and ex vivo. We found that plasma and platelet ANGPTL2 levels were elevated in patients with STEMI with SR compared to those in non-SR (NSR) patients, and was an independent predictor of SR. Angptl2 deficiency accelerated mesenteric artery thrombosis induced by FeCl3 in Angptl2-/- compared to WT animals, promoted platelet granule secretion and aggregation induced by thrombin and collogen while purified ANGPTL2 protein supplementation reversed collagen-induced platelet aggregation. Angptl2 deficiency also increased platelet spreading on immobilized fibrinogen and clot contraction. In collagen-stimulated Angptl2-/- platelets, Src homology region 2 domain-containing phosphatase (Shp)1-Y564 and Shp2-Y580 phosphorylation were attenuated while Src, Syk, and Phospholipase Cγ2 (PLCγ2) phosphorylation increased. Our results demonstrate that ANGPTL2 negatively regulated thrombus formation by activating ITIM which can suppress ITAM signaling pathway. This new knowledge provides a new perspective for designing future antiplatelet aggregation therapies.

Triglyceride-rich lipoprotein, remnant cholesterol, and apolipoproteins CII, CIII, and E in patients with schizophrenia

Patients with schizophrenia show a disproportionally increased risk of cardiovascular disease. Hypertriglyceridemia is prevalent in this population; however, how this relates to levels of remnant cholesterol, triglyceride (TG)-rich lipoprotein (TRL) particle size and composition, TG turnover, and apolipoprotein (apo) and angiopoietin-like protein (ANGPTL) concentrations is unknown. Fasting levels of cholesterol (total [TC], LDL-C, HDL-C, non-HDL-C and remnant cholesterol) and TG were determined in 110 patients diagnosed with schizophrenia, and 46 healthy controls. TRL particle size, concentration and composition, and β-hydroxybutyrate (TG turnover marker) were assessed by NMR. Levels of apoCII, apoCIII, apoE, ANGPTL3, ANGPTL4, and ANGPTL8 were measured by ELISA, and apoCII, apoCIII and apoE were further evaluated in HDL and non-HDL fractions. Patients with schizophrenia had significantly elevated TG, TG:apoB ratio, non-HDL-C, remnant cholesterol, non-HDL-apoCII and non-HDL-apoCIII, and HDL-apoE (all P < 0.05), lower HDL-C and apoA-I (all P < 0.001), and comparable apoB, TC, TC:apoB ratio, LDL-C, β-hydroxybutyrate, ANGPTL3, ANGPTL4 and ANGPTL8 to healthy controls. Patients had a 12.0- and 2.5-fold increase in the concentration of large and medium TRL particles respectively, but similar cholesterol:TG ratio within each particle. Plasma TG, remnant cholesterol, and large and medium TRL particle concentrations correlated strongly with apoCII, apoCIII, and apoE in the non-HDL fraction, and with apoCIII and apoE in the HDL fraction in patients with schizophrenia. Differences in TG, HDL-C, TRL particle concentrations, apoCIII, and apoE persisted after adjustment for conventional risk factors. These results are consistent with impaired TRL lipolysis and clearance in patients with schizophrenia which may be responsive to targeting apoCIII.

Predicting Major Adverse Carotid Cerebrovascular Events in Patients with Carotid Stenosis: Integrating a Panel of Plasma Protein Biomarkers and Clinical Features-A Pilot Study.

Background: Carotid stenosis (CS) is an atherosclerotic disease of the carotid artery that can lead to devastating cardiovascular outcomes such as stroke, disability, and death. The currently available treatment for CS is medical management through risk reduction, including control of hypertension, diabetes, and/or hypercholesterolemia. Surgical interventions are currently suggested for patients with symptomatic disease with stenosis >50%, where patients have suffered from a carotid-related event such as a cerebrovascular accident, or asymptomatic disease with stenosis >60% if the long-term risk of death is <3%. There is a lack of current plasma protein biomarkers available to predict patients at risk of such adverse events. Methods: In this study, we investigated several growth factors and biomarkers of inflammation as potential biomarkers for adverse CS events such as stroke, need for surgical intervention, myocardial infarction, and cardiovascular-related death. In this pilot study, we use a support vector machine (SVM), random forest models, and the following four significantly elevated biomarkers: C-X-C Motif Chemokine Ligand 6 (CXCL6); Interleukin-2 (IL-2); Galectin-9; and angiopoietin-like protein (ANGPTL4). Results: Our SVM model best predicted carotid cerebrovascular events with an area under the curve (AUC) of >0.8 and an accuracy of 0.88, demonstrating strong prognostic capability. Conclusions: Our SVM model may be used for risk stratification of patients with CS to determine those who may benefit from surgical intervention.