Angiopoietin-like Protein 2 Levels Research Articles

ANGPTL3 diminishes the resistance of ovarian cancer to paclitaxel by blocking the PI3K-AKT-mTOR signaling pathway

Angiopoietin-like protein 3 (ANGPTL3) is key in ovarian cancer (OC) cell growth and metastasis, notably by enhancing natural killer cells' capacity for inducing cell toxicity and apoptosis. However, its role in influencing chemotherapy resistance in OC remains ambiguous. In this study, we discovered a correlation between reduced ANGPTL3 levels and a less favorable outcome in OC patients using the Kaplan-Meier Plotter database. Lower levels of ANGPTL3 were detected in paclitaxel (PTX)-resistant OC tissues and cell lines via western blotting and immunohistochemistry. To investigate ANGPTL3's effects, we established SKOV3/PTX and 2780/PTX as PTX-resistant OC cell lines by incrementally increasing PTX exposure and then transfecting them with overexpress ANGPTL3 (OE-ANGPTL3) lentivirus. We conducted various assays such as CCK-8, colony formation, Edu staining, flow cytometry, and transwell to investigate the impact of ANGPTL3 on PTX resistance. Additionally, this effect was examined in a mouse subcutaneous xenograft model. Both in vitro and in vivo experiments demonstrated that ANGPTL3 overexpression mitigated PTX resistance in OC cells by inactivating the PI3K-AKT-mTOR pathway. In summary, our research reveals that ANGPTL3 enhances PTX sensitivity in OC by downregulating the PI3K-AKT-mTOR pathway. The study of this study suggest that ANGPTL3 could serve as a valuable therapeutic target for OC, signifying its clinical relevance in OC management.

T266M variants of ANGPTL4 improve lipid metabolism by modifying their binding affinity to acetyl-CoA carboxylase in obstructive sleep apnea

Background Angiopoietin-like protein 4 (ANGPTL4) is recognized as a crucial regulator in lipid metabolism. Acetyl-CoA carboxylases (ACACAs) play a role in the β-oxidation of fatty acids. Yet, the functions of ANGPTL4 and ACACA in dyslipidemia of obstructive sleep apnea (OSA) remain unclear. Methods This study included 125 male OSA subjects from the Shanghai Sleep Health Study (SSHS) who were matched for age, body mass index (BMI), and lipid profile. Serum ANGPTL4 levels were measured via ELISA. The ANGPTL4 T266M variants of 4455 subjects along with their anthropometric, fasting biochemical, and standard polysomnographic parameters were collected. Linear regression was used to analyze the associations between quantitative traits and ANGPTL4 T266M. Molecular docking and molecular dynamic simulation were employed to compare the effects of the wild-type ANGPTL4 and its T266M mutation on ACACA. Results Serum ANGPTL4 levels significantly decreased with increasing OSA severity (non-OSA: 59.6 ± 17.4 ng/mL, mild OSA: 50.0 ± 17.5 ng/mL, moderate OSA: 46.3 ± 15.5 ng/mL, severe OSA: 19.9 ± 14.3 ng/mL, respectively, p = 6.02 × 10−16). No associations were found between T266M and clinical characteristics. Molecular docking indicated that mutant ANGTPL4 T266M had stronger binding affinity for the ACACA protein, compared with wild-type ANGPTL4. In terms of protein secondary structure, mutant ANGTPL4 T266M demonstrated greater stability than wild-type ANGPTL4. Conclusions Serum ANGTPL4 levels were significantly decreased in OSA patients, particularly among individuals with severe OSA. Although functional ANGTPL4 T266M variants were not associated with lipid levels in OSA, ANGTPL4 T266M could enhance binding affinity for the ACACA protein, potentially regulating lipid metabolism.

The Effect of Canagliflozin on High-Density Lipoprotein Cholesterol and Angiopoietin-Like Protein 3 in Type 2 Diabetes Mellitus.

Diabetes mellitus is often accompanied by dyslipidemia. Sodium-glucose cotransporter-2 (SGLT2) inhibitors, as a novel therapeutic agent for the treatment of type 2 diabetes mellitus (T2DM), have been reported to exert effects on lipid, while the results remain controversial. This study is aimed at exploring the effect of SGLT2 inhibitor canagliflozin on lipid profile. This study was a single-center, open-label, nonrandomized, prospective study. Metformin (500 mg three times per day) or canagliflozin (100 mg, once daily) was administered for 12 weeks. Fasting blood samples were collected before and 12 weeks after treatment. Serum lipid profile levels and angiopoietin-like protein 3 (ANGPTL3) were determined. In animal experiment, C57BL/6 J mice were divided into three groups including control, STZ + HFD, and STZ + HFD + canagliflozin. Lipid profile and plasma ANGPTL3 level were measured after 12 week's treatment. Moreover, the expression of ANGPTL3 was detected in the liver tissues. There was a decreased trend in low-density lipoprotein cholesterol (LDL-c) and triglycerides (TG) after canagliflozin treatment, while canagliflozin significantly increased high-density lipoprotein cholesterol (HDL-c) level and decreased plasma ANGPTL3 level. In addition, the expression of ANGPTL3 in liver tissues decreased obviously in diabetic mice with canagliflozin treatment. Canagliflozin increases HDL-c level and suppresses ANGPTL3 expression in patients with T2DM and diabetic mice. The reduction of ANGPTL3 may contribute to the increase of HDL-c. However, the specific mechanism needs further research. This trial is registered with ChiCTR1900021231.

High serum angiopoietin-like protein-4 levels are associated with gestational hypertension and preeclampsia: a case-control study

Abstract Objectives Investigation of angiopoietin-like protein-4 (ANGPTL-4) and vascular endothelial growth factor A (VEGF-A) levels as a biochemical marker in gestational hypertension (GH) and preeclampsia (PE), which are known to have important roles in the maintenance of angiogenesis and endothelial functions. Methods Total of 90 patients included in this case-control study. Group 1 (G1) (n=30)=patients with healthy pregnancy between 37 and 41 weeks, G2 (n=30)=patients diagnosed with gestational hypertension between 20 and 37 weeks, G3 (n=30)=patients diagnosed with preeclampsia between 20 and 37 weeks. The sera obtained from the patients were stored at −80 °C until they were studied. Demographic parameters, systolic, diastolic and mean arterial blood pressure were recorded. VEGF-A and ANGPTL-4 levels were studied with enzyme-linked immunosorbent assay (ELISA) kit. Results The mean age was similar in both groups. The number of primigravida pregnant was higher in G2 and G3 than in G1. Gestational week was more advanced in G1 compared to G2 and G3. While ANGPTL-4 and VEGF-A levels were similar between G2 and G3, they were significantly higher in both groups compared to G1. Conclusions We showed that ANGPTL-4 and VEGF-A levels were elevated in maternal serum in GH and PE cases. Increased maternal serum ANGPTL-4 levels may be a biomarker that can be used in the early diagnosis of PE.

Correlation between the serum FABP4, ANGPTL3, and ANGPTL4 levels and coronary artery disease.

Lipid metabolism related factors, such as angiopoietin-like protein 3 (ANGPTL3), angiopoietin-like 4 (ANGPTL4), fatty acid-binding protein 4 (FABP4) are newly discovered factors that can affect coronary artery disease (CAD). In this study, we aimed to investigate the relationship between CAD and these lipid metabolism factors. ANGPTL3, ANGPTL4, and FABP4 may provide a new method for the control of CAD risk factors and the prevention and treatment of CAD. We enrolled 284 consecutive inpatients with suspected CAD and divided them into CAD and non-CAD groups based on the coronary angiography results. Serum ANGPTL3, ANGPTL4, FABP4, and tumor necrosis factor-α (TNF-α) levels were estimated using the enzyme-linked immunosorbent assay. Multivariate logistic regression was used to assess the risk factors for CAD. The receiver operating characteristic curve was used to determine the cutoff and diagnostic values. The serum TNF-α, FABP4, ANGPTL3, and ANGPTL4 values showed a significant difference between the CAD and non-CAD groups (p < .05). After adjusting for confounding factors, the FABP4, ANGPTL3, and ANGPTL4 levels were independently associated with CAD (p < .05). The ANGPTL3 expression level was an independent risk factor for CAD in patients with hypertension, but not in those without hypertension. The ANGPTL3 > 67.53 ng/mL, ANGPTL4 > 29.95 ng/mL, and FABP4 > 1421.25 ng/L combination had the highest diagnostic value for CAD. ANGPTL3, ANGPTL4, and FABP4 were identified as independent risk factors for CAD and have valuable clinical implications for the diagnosis and treatment of CAD.

Correlation between serum ANGPTL4 levels and white matter hyperintensity and cognitive impairment in patients with cerebral small vessel disease

AbstractObjectivesTo investigate the correlation between serum angiopoietin‐like protein 4 (ANGPTL4) levels, white matter hyperintensity (WMH), and cognitive impairment (CI) in patients with cerebral small vessel disease (CSVD).MethodsThis cross‐sectional study enrolled 171 patients with CSVD who attended the First Affiliated Hospital of Xinxiang Medical University from December 2021 to July 2022. All subjects underwent a 3.0T head magnetic resonance imaging, neuropsychology assessment, and blood sampling. Serum ANGPTL4 levels were detected by enzyme‐linked immunosorbent assay and the severity of WMH was assessed by the Fazekas scale. According to the Montreal Cognitive Assessment (MoCA) scale, subjects were divided into normal cognition group (NC, n = 80) and CI group (n = 91). According to the total Fazekas scores, subjects were divided into a mild WMH group (n = 84), a moderate WMH group (n = 70), and a severe WMH group (n = 17).ResultsSerum ANGPTL4 levels were significantly higher in the CI group than in the NC group (p &lt; .05) and were negatively correlated with mini–mental state examination scores and MoCA scores (r = −0.26, −0.341, p &lt; .05). Serum ANGPTL4 levels increased significantly in the mild to moderate WMH group but tended to decrease in the severe WMH group. Binary logistic regression analysis showed that ANGPTL4 was an independent influencing factor for CSVD‐CI (OR = 2.062, 95% CI (1.591–2.674), p &lt; .001). The area under curve of ANGPTL4 for CSVD‐CI was 0.847 (0.791–0.903).ConclusionANGPTL4 may be involved in the process of white matter damage and CI in CSVD patients and shows a diagnostic value for CSVD‐CI.

Downregulating ANGPTL3 by miR-144-3p promoted TGF-β1-induced renal interstitial fibrosis via activating PI3K/AKT signaling pathway

Despite observations of decreased ANGPTL3 (angiopoietin-like protein 3) levels in tubular atrophy and renal interstitial fibrosis (RIF), its functional implications and regulatory mechanisms in RIF remain unclear. This investigation employed unilateral ureteral obstruction (UUO) mice as in vivo model and human proximal kidney tubuloepithelial HK-2 cells under TGF-β1 treatment as in vitro model to explore RIF. The RIF extent was evaluated using H & E staining and Masson's trichrome staining. There was a significant decrease in ANGPTL3 levels and an increase in miR-144-3p, accompanied by heightened expressions of α-SMA, p-PI3K, p-AKT, Collagen I, and Fibronectin in the UUO mice and HK-2 cells treated with TGF-β1. Enhancing ANGPTL3 expression or suppressing miR-144-3p mitigated TGF-β1-induced cellular apoptosis, inflammation, and PI3K/AKT signaling pathway activation, as evidenced by altered levels of α-SMA, Collagen I, Fibronectin, and associated signaling markers. Using a bioinformatics approach, a miR-144-3p binding site was discovered on the ANGPTL3 mRNA, and this finding was subsequently confirmed through luciferase reporter assay. In HK-2 cells stimulated with TGF-β1, the suppression of ANGPTL3 negated the effects of inhibiting miR-144-3p. Under comparable conditions, the use of LY294002, an inhibitor of the PI3K/AKT pathway, nullified the effects caused by the knockdown of ANGPTL3. Collectively, these findings indicate that miR-144-3p exacerbates RIF through PI3K/AKT pathway activation by targeting ANGPTL3, highlighting a novel potential therapeutic target for RIF management.

Correlation of serum VEGF-C, ANGPTL4, and activin A levels with frailty

BackgroundSecretory factors linked to lymphogenesis, such as vascular endothelial growth factor C (VEGF-C), angiopoietin like protein 4 (ANGPTL4), and activin A (ACV-A), have been recognized as potential markers of chronic inflammatory status and age-related diseases. Furthermore, these factors may also be linked to frailty. The primary objective of this study was to examine the serum VEGF-C, ANGPTL4, and ACV-A levels in young individuals, healthy older individuals, and older individuals with pre-frailty and frailty, and to determine their association with pro-inflammatory factor levels. MethodsWe conducted an observational study, enrolling a total of 210 older individuals and 20 young healthy volunteers. Participants were divided into four groups based on the Freid frailty phenotype: healthy young group, older patients without frailty group, pre-frail older group, and frail older group. Plasma and peripheral blood mononuclear cells (PBMCs) were collected from all four groups. ELISA was used to measure the serum levels of VEGF-C, ANGPTL4, ACV-A, and pro-inflammatory cytokines, while RT-qPCR was used to measure the transcription level of VEGF-C, ANGPTL4 and ACV-A in PBMCs. ResultsIn comparison to healthy young individuals and older participants without frailty, older participants with frailty exhibited lower renal function, higher serum levels and transcription levels of VEGF-C, ANGPTL4, ACV-A, and elevated levels of pro-inflammatory cytokines (CRP, IL-1β, and TNF-α). Multiple linear regression analysis revealed that serum levels of VEGF-C, ANGPTL4, and ACV-A were positively correlated with the frailty index, independent of age, eGFR, and comorbidities. Furthermore, the receiver operating characteristic (ROC) curve analysis demonstrated that serum levels of VEGF-C, ANGPTL4, and ACV-A have great accuracy in predicting frailty. ConclusionElevated serum levels of VEGF-C, ANGPTL4, and ACV-A are associated with frailty status.

Serum Angiopoietin-like Protein 3 Levels Are Associated with Endothelial Function in Patients with Maintenance Hemodialysis.

Angiopoietin-like protein 3 (ANGPTL3) plays an important role in lipid and lipoprotein trafficking and metabolism and is positively correlated with cardiovascular disease. Our objective was to evaluate the association between serum ANGPTL3 levels and endothelial function in patients on maintenance hemodialysis (MHD). We enrolled 116 patients on MHD and obtained their blood test results from their medical records. Using a noninvasive digital thermal monitor, we determined the vascular reactivity index (VRI) as a measure of endothelial function. Serum ANGPTL3 concentration was measured by a commercial-enzyme-linked immunosorbent assay. Vascular reactivity was classified as poor in 17 (14.7%) patients, intermediate (1.0 ≤ VRI < 2.0) in 50 (43.1%) patients, and high (VRI ≥ 2.0) in 49 (42.2%) patients. Serum levels of ANGPTL3 (p < 0.001) and alkaline phosphatase (ALP, p = 0.025) increased significantly as the VRI decreased. The log-transformed serum ALP (log-ALP, r = -0.187, p = 0.045) and log-ANGPTL3 (r = -0.319, p < 0.001) showed a negative correlation with the VRI on univariate linear regression analysis. A significant negative correlation was found between log-ANGPTL3 and VRI (p < 0.001) on multivariate stepwise linear regression analysis. The findings of our investigation showed that, in patients with MHD, the ANGPTL3 concentration had a negative correlation with the VRI.

Emerging insights into the roles of ANGPTL8 beyond glucose and lipid metabolism.

Angiopoietin-like protein 8 (ANGPTL8) is a secreted protein predominantly expressed in liver and adipose tissue. ANGPTL8 modulates the clearance of triglycerides (TGs) by suppressing the activity of lipoprotein lipase (LPL) within the plasma. Previous studies found that circulating ANGPTL8 levels were significantly increased in metabolic disorder-related diseases, such as type 2 diabetes mellitus (T2DM), obesity, metabolic syndrome and nonalcoholic fatty liver disease (NAFLD). Whether ANGPTL8 has a direct pathogenic role in these diseases remains to be determined. In this review, we summarize the emerging roles of ANGPTL8 in the regulation of inflammation, tumours, circulatory system-related diseases, and ectopic lipid deposition, which may provide new insights into the diverse functions of ANGPTL8 in various diseases beyond its well-established functions in glucose and lipid metabolism.

THU068 Evaluation Of Nonalcoholic Fatty Liver Disease, Liver Fibrosis And Serum Angiopoietin-like Protein Levels In Patients With Acromegaly

Abstract Disclosure: I. Eroglu: None. B. Gonul Iremli: None. I. Idilman: None. D. Yuce: None. I. Lay: None. D. Akata: None. T. Erbas: None. Background: Due to their impaired glucose and lipid metabolism, acromegaly patients are potentially at risk for NAFLD. However, limited data exist about acromegaly and NAFLD relation. In this study (cross-sectional, case-controlled), we evaluated the risk of NAFLD and hepatic fibrosis in acromegalic patients and its association with noninvasive hepatosteatosis scores (NS) and angiopoietin-like protein-8 (ANGPTL-8) level for the first time in the literature. Methods: Thirty-two (15F/17M - median age=50.15 yrs) acromegalic patients (n=15 active acromegaly - AA and n=17 controlled acromegaly - CA) compared to 19 healthy controls (C) in terms of liver fat ratio (LFR), liver stiffness measurement (LSM), and ANGPTL-8 levels. Subjects had MRI-PDFF to determine LFR and MR elastography to quantify LSM. NAFLD was confirmed in those with LFR of ≥5%, and increased LSM in those with LSM of ≥2.5 kPa. VAI (visceral adipocity index), FLI (fatty liver index), HSI (hepatic steatosis index), and TyG (Triglyceride-glucose index) were calculated as NS. Results: Age, gender and BMI were similiar across groups. The GH and IGF-1 levels in AA group was greater than in CA, and C (p&amp;lt; 0.001). The CA had greater frequency of NAFLD than AA (p&amp;lt;0.001). Increased LSM was detected in three (21.4%) of AA, four (23.5%) of CA, and two (10.5%) of C.The median LFR was 1.75% in the AA group, 6.5% in the CA group, and 3.5% in the control group. LFR was lower in the AA group than in the CA (p=0.026). According to MRI-PDFF results, none of the patients in the AA group were diagnosed with NAFLD, while 58.8% (n=10) in the CA group and 26.3% (n=5) in the control group were diagnosed with NAFLD. The prevalence of NAFLD was found to be higher in the CA group than in the AA group (p&amp;lt;0.001). In acromegaly patients, LFR was positively correlated with TyG (r=0.675, p&amp;lt;0.001), VAI (r=0.508, p=0.004), and FLI (r=0.482, p=0.006). However, no correlation was seen between LFR and traditional risk factors for NAFLD (including BMI, waist circumference, Hba1c, HOMA-IR, and CRP) in acromegalics.ANGPTL-8 was lower in CA group (0.61 ng/mL) than in AA group (0.89 ng/mL) (p=0.006). When all acromegaly patients were evaluated independently, those with NAFLD had lower ANGPTL-8 levels than those without NAFLD (p=0.036). Conclusion: In conclusion, high GH levels seem to be protective against fatty liver in patients with active acromegaly, even if the metabolic profileis impaired. There was no relation observed between LFR and conventional risk factors in acromegaly patients. The strongest connection was found between LFR and TyG index among the noninvasive hepatosteatosis scores. ANGPTL-8 levels were lower in acromegaly patients with NAFLD, suggesting that high levels represent a reaction to insulin resistance rather than a cause of NAFLD. Treatment planning at a level that does not cause GH deficiency while maintaining disease control may be helpful to prevent NAFLD in acromegaly. Presentation: Thursday, June 15, 2023

Serum ANGPTL4 and SIRT1 factor levels and the Carotid Atherosclerotic plaque stability relationship analysis.

This study was to investigate the relationship between the levels of Angiopoietin-Like Protein 4 (ANGPTL4) and Silent Mating-type Information Regulation 2 Homolog 1 (SIRT1) and the stability of carotid atherosclerotic plaque. For this purpose, 108 patients with coronary heart disease in our hospital from Jan 2021 to May 2022 were selected as the coronary heart disease (CHD) group and 80 patients with the healthy examination as the control group. Patients' serum levels of ANGPTL4 and SIRT1 were collected, and their stability of carotid atherosclerotic plaque was determined by carotid ultrasound. According to their stability results, patients were divided into three subgroups: No plaque, Stable plaque, and Unstable plaque. The serum ANGPTL4 and SIRT1 levels were analyzed in different groups, and the correlation between their serum levels and the stability of carotid atherosclerotic plaque was analyzed by rank correlation. Results showed that the CHD group's serum ANGPTL4 and SIRT1 levels were lower, with statistical significance (P<0.05); A statistically significant difference in serum ANGPTL4 and SIRT1 levels were observed among patients with No plaques, Stable plaques, and Unstable plaques (P<0.05); A negative correlation was observed between serum levels of ANGPTL4 and SIRT1 and the stability of carotid atherosclerotic plaque (r=-0.438, -0.717, P<0.001); Serum ANGPTL4 and SIRT1 can be used as the evaluation method of carotid atherosclerotic plaque stability. When ANGPTL4 ≤ 30.17mg/L and SIRT1 ≤ 6.91μg/L, patients were more likely to develop unstable plaques; When ANGPTL4 ≤ 30.40mg/L and SIRT1 ≤ 6.87μg/L, patients were more likely to develop plaques (instability and/or stability). In conclusion, the serum levels of ANGPTL4 and SIRT1 in patients with CHD decreased. ANGPTL4 and SIRT1 will participate in the formation and development of carotid plaque, which can be used as a serological evaluation index to evaluate the occurrence and carotid atherosclerotic plaque's stability.

Nonalcoholic Fatty Liver Disease, Liver Fibrosis, and Utility of Noninvasive Scores in Patients With Acromegaly.

Nonalcoholic fatty liver disease (NAFLD) is a metabolical disorder and can lead to liver fibrosis. Because it is commonly seen, several noninvasive scores (NS) have been validated to identify high-risk patients. Patients with NAFLD have been shown to have higher serum angiopoietin-like protein-8 (ANGPTL-8) levels. The risk of NAFLD is known insufficiently in acromegaly. Moreover, the utility of the NS and the link between NAFLD and ANGPTL-8 in acromegaly is unknown. Thirty-two patients with acromegaly (n = 15, active [AA] and n = 17, controlled acromegaly [CA]) and 19 healthy controls were included. Magnetic resonance imaging (MRI)-proton density fat fraction (PDFF) was used to evaluate hepatic steatosis, and magnetic resonance elastography to evaluate liver stiffness measurement. ANGPTL-8 levels were measured with ELISA. Median liver MRI-PDFF and NAFLD prevalence in AA were lower than in CA (P = .026 and P < .001, respectively). Median magnetic resonance elastography-liver stiffness measurement were similar across groups. Of the NS, visceral adiposity index, fatty liver index, hepatic steatosis index, and triglyceride-glucose index (TyG) all showed positive correlation with the liver MRI-PDFF in the control group. However, only TyG significantly correlated with liver fat in the AA and CA groups. There was no correlation between traditional NAFLD risk factors (body mass index, waist circumference, C-reactive protein, homeostasis model assessment for insulin resistance, visceral adipose tissue) and liver MRI-PDFF in the AA and CA. Patients with acromegaly with NAFLD had lower GH, IGF-1, and ANGPTL-8 levels than in those without NAFLD (P = .025, P = .011, and P = .036, respectively). Active acromegaly may protect from NAFLD because of high GH. In patients with acromegaly, NAFLD risk cannot be explained with classical risk factors; hence, additional risk factors must be identified. TyG is the best score to evaluate NAFLD risk. Lower ANGPTL-8 in patients with acromegaly and NAFLD implies this hormone may be raised because of insulin resistance rather than being a cause for NAFLD.

Culprit lesion plaque characteristics and angiopoietin like 4 in acute coronary syndrome: A virtual histology-intravascular ultrasound analysis

BackgroundThin-cap fibroatheroma is a rupture-prone vulnerable plaque that leads to acute coronary syndrome (ACS). However, its underlying mechanisms are not fully understood. Several studies have investigated the clinical association between angiopoietin-like protein 4 (ANGPTL4) and coronary artery disease. Therefore, this study aimed to investigate the correlation of plasma ANGPTL4 in culprit lesion of ACS patients using intravascular ultrasound (IVUS) and virtual-histology IVUS (VH-IVUS). MethodsFifty patients newly diagnosed with ACS between March to September 2021 were selected. Blood samples for baseline laboratory tests, including ANGPTL4, were collected before percutaneous coronary intervention (PCI), and all pre- and post-PCI IVUS examinations were performed of the culprit lesions. ResultsLinear regression analysis between plasma ANGPTL4 and grayscale IVUS/VH-IVUS parameters revealed that plasma ANGPTL4 was strongly correlated with the necrotic core (NC) of the minimal lumen site (r = −0.666, p = 0.003) and largest NC site (r = −0.687, p < 0.001), and patients with lower plasma ANGPTL4 levels showed a significantly higher proportion of TFCA. ConclusionThe present study further demonstrated the protective role of ANGPTL4 in the spectrum of atherosclerotic development in patients with ACS by culprit lesion morphology analysis using IVUS and VH-IVUS.

ANGPTL8 Deletion Attenuates Abdominal Aortic Aneurysm Formation in ApoE-/- Mice.

Angiopoietin-like protein 8 (ANGPTL8) plays important roles in lipid metabolism, glucose metabolism, inflammation, and cell proliferation and migration. Clinical studies have indicated that circulating ANGPTL8 levels are increased in patients with thoracic aortic dissection (TAD). TAD shares several risk factors with abdominal aortic aneurysm (AAA). However, the role of ANGPTL8 in AAA pathogenesis has never been investigated. Here, we investigated the effect of ANGPTL8 knockout on abdominal aortic aneurysm (AAA) in ApoE-/- mice. ApoE-/-ANGPTL8-/- mice were generated by crossing ANGPTL8-/- and ApoE-/- mice. AAA was induced in ApoE-/- using perfusion of angiotensin II (AngII). ANGPTL8 was significantly upregulated in AAA tissues of human and experimental mice. Knockout of ANGPTL8 significantly reduced AngII-induced AAA formation, elastin breaks, aortic inflammatory cytokines, matrix metalloproteinase expression, and smooth muscle cell apoptosis in ApoE-/- mice. Similarly, ANGPTL8 sh-RNA significantly reduced AngII-induced AAA formation in ApoE-/- mice. ANGPTL8 deficiency inhibited AAA formation, and ANGPTL8 may therefore be a potential therapeutic target for AAA.

Plasma insulin is required for the increase in plasma angiopoietin-like protein 8 in response to nutrient ingestion.

Plasma levels of angiopoietin-like protein 8 (ANGPTL8) are regulated by feeding and they increase following glucose ingestion. Because both plasma glucose and insulin increase following food ingestion, we aimed to determine whether the increase in plasma insulin and glucose or both are responsible for the increase in ANGPTL8 levels. ANGPTL8 levels were measured in 30 subjects, 14 with impaired fasting glucose (IFG), and 16 with normal fasting glucose (NFG); the subjectsreceived 75g glucose oral Glucose tolerance test (OGTT), multistep euglycaemic hyperinsulinemic clamp and hyperglycaemic clamp with pancreatic clamp. Subjects with IFG had significantly higher ANGPTL8 than NGT subjects during the fasting state (p<0.05). During the OGTT, plasma ANGPTL8 concentration increased by 62% above the fasting level (p<0.0001), and the increase above fasting in ANGPTL8 levels was similar in NFG and IFG individuals. During the multistep insulin clamp, there was a dose-dependent increase in plasma ANGPTL8 concentration. During the 2-step hyperglycaemic clamp, the rise in plasma glucose concentration failed to cause any change in the plasma ANGPTL8 concentration from baseline. In response to nutrient ingestion, ANGPTL8 level increased due to increased plasma insulin concentration, not to the rise in plasma glucose. The incremental increase above baseline in plasma ANGLPTL8 during OGTT was comparable between people with normal glucose tolerance and IFG.

Plasma ANGPTL8 Levels and Risk for Secondary Cardiovascular Events in Japanese Patients With Stable Coronary Artery Disease Receiving Statin Therapy.

The ability to predict secondary cardiovascular events could improve health of patients undergoing statin treatment. Circulating ANGPTL8 (angiopoietin-like protein 8) levels, which positively correlate with proatherosclerotic lipid profiles, activate the pivotal proatherosclerotic factor ANGPTL3. Here, we assessed potential association between circulating ANGPTL8 levels and risk of secondary cardiovascular events in statin-treated patients. We conducted a biomarker study with a case-cohort design, using samples from a 2018 randomized control trial known as randomized evaluation of high-dose (4 mg/day) or low-dose (1 mg/day) lipid-lowering therapy with pitavastatin in coronary artery disease (REAL-CAD [Randomized Evaluation of Aggressive or Moderate Lipid-Lowering Therapy With Pitavastatin in Coronary Artery Disease])." From that study's full analysis set (n=12 413), we selected 2250 patients with stable coronary artery disease (582 with the primary outcome, 1745 randomly chosen, and 77 overlapping subjects). A composite end point including cardiovascular-related death, nonfatal myocardial infarction, nonfatal ischemic stroke, or unstable angina requiring emergent admission was set as a primary end point. Circulating ANGPTL8 levels were measured at baseline and 6 months after randomization. Over a 6-month period, ANGPTL8 level changes significantly decreased in the high-dose pitavastatin group, which showed 19% risk reduction of secondary cardiovascular events compared with the low-dose group in the REAL-CAD [Randomized Evaluation of Aggressive or Moderate Lipid-Lowering Therapy With Pitavastatin in Coronary Artery Disease] study. In the highest quartiles, relative increases in ANGPTL8 levels were significantly associated with increased risk for secondary cardiovascular events, after adjustment for several cardiovascular disease risk factors and pitavastatin treatment (hazard ratio in Q4, 1.67 [95% CI, 1.17-2.39). Subgroup analyses showed relatively strong relationships between relative ANGPTL8 increases and secondary cardiovascular events in the high-dose pitavastatin group (hazard ratio in Q4, 2.07 [95% CI, 1.21-3.55]) and in the low ANGPTL8 group at baseline (166 <pmol/L, hazard ratio in Q4: 1.74, [95% CI, 1.04-2.93]). Monitoring ANGPTL8 levels over time might be useful to assess residual risk of cardiovascular secondary events in patients with cardiovascular disease undergoing statin therapy.

Novel Insights of ANGPTL-3 on Modulating Cholesterol Efflux Capacity Induced by HDL Particle

Angiopoietin-like protein 3 (ANGPTL-3) modulates lipid metabolism and the risk of coronary artery disease (CAD), especially stable angina (SA), via suppressing lipoprotein lipase (LPL). However, whether there are other mechanisms is not elucidated yet. The current research explored the modulatory roles of ANGPTL-3 on high-density lipoprotein (HDL), which further affects atherosclerotic development. A total of 200 individuals were enrolled in the present study. Serum ANGPTL-3 levels were detected via enzyme-linked immunosorbent assays (ELISA). Cholesterol efflux capacity induced by HDL particles was detected through H3-cholesterol loading THP-1 cell. The serum ANGPTL-3 levels presented no significant discordance between the SA group and the non-SA group, whereas the serum ANGPTL-3 levels in type 2 diabetes mellitus (T2DM) group were significantly elevated compared with those in the non-T2DM group [428.3 (306.2 to 736.8) ng/ml vs. 298.2 (156.8 to 555.6) ng/ml, P <0.05]. Additionally, the serum ANGPTL-3 levels were elevated in patients with low TG levels compared to those in patients with high TG levels [519.9 (377.6 to 809.0) ng/ml vs. 438.7 (329.2 to 681.0) ng/ml, P <0.05]. By comparison, the individuals in the SA group and T2DM group presented decreased cholesterol efflux induced by HDL particles [SA: (12.21±2.11)% vs. (15.51±2.76)%, P <0.05; T2DM: (11.24±2.13)% vs. (14.65±3.27)%, P <0.05]. In addition, the serum concentrations of ANGPTL-3 were inversely associated with the cholesterol efflux capacity of HDL particles (r=-0.184, P <0.05). Through regression analysis, the serum concentrations of ANGPTL-3 were found to be an independent modulator of the cholesterol efflux capacity of HDL particles (standardized β=-0.172, P <0.05). ANGPTL-3 exhibited a negative modulatory function on cholesterol efflux capacity induced by HDL particles.

Relationship between angiopoietin-like-protein-2 levels and anti-mullerian hormone levels in polycystic ovary syndrome of reproductive age

Introduction: Polycystic Ovary Syndrome (PCOS) is the most prevalent metabolic disease affecting reproductive-age women and is often present with insulin resistance. Angiopoietin-like-protein-2 (ANGPTL2) is an angiogenic factor influencing insulin resistance in PCOS, manifesting in the anti-mullerian hormone (AMH). There are no previous studies regarding the relationship between ANGPTL2 levels and AMH in PCOS. The study aims to analyse the relationship between ANGPTL2 and AMH levels in PCOS and to compare ANGPTL2 and AMH levels between PCOS phenotypes. Methods: This cross-sectional study on 43 women aged 18-40 diagnosed with PCOS according to the Rotterdam criteria. Subjects were recruited consecutively and categorized into four PCOS phenotypes. Serum levels of ANGPTL2 and AMH were measured and analysed by correlation and comparison test using SPSS 26. Results: A total of 43 PCOS samples were included in the study within 4 months. Based on the severity, phenotype A (anovulation, hyperandrogenic and polycystic ovaries) showed the highest levels of ANGPTL2 and AMH. There was no significant difference in ANGPTL2 levels between the PCOS phenotypes. There was a significant difference in AMH levels between phenotypes, where the highest value was between phenotypes A and B. There was a positive correlation between ANGPTL2 and AMH levels. Conclusion: There is a positive relationship between ANGPTL2 and AMH serum levels. The ANGPTL2 serum levels were not significantly different. In contrast, the AMH serum levels significantly differed across the four PCOS phenotypes, with the highest level found in phenotype A.

Angiopoietin-like protein 8 deficiency attenuates thoracic aortic aneurysm/dissection development in β-aminopropionitrile monofumarate-induced model mice

Thoracic aortic aneurysm/dissection (TAAD) is a life-threatening cardiovascular disorder. Endoplasmic reticulum stress (ERS) and vascular smooth muscle cell (VSMC) apoptosis are involved in TAAD progression. The Protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK) pathway is associated with VSMC apoptosis. Serum Angiopoietin-Like Protein 8 (ANGPTL8) levels are associated with aortic diameter and rupture rate of TAAD. However, a direct role of ANGPTL8 in TAAD has not been determined. β-Aminopropionitrile monofumarate (BAPN) was used to induce TAAD in C57BL/6 mice. ANGPTL8 knockout mice were used to detect the effects of ANGPTL8 on TAAD development. ANGPTL8knockdown in vitro was used to analyze the role of ANGPTL8 in VSMCs and ERS. In addition, over-expression of ANGPTL8 in VSMCs and a PERK inhibitor were used to assess the effect of ANGPTL8 on the PERK pathway. ANGPTL8 levels were increased in the aortic wall and VSMCs of BAPN-induced TAAD mice. Compared with BAPN-treated wild-type mice, ANGPTL8 knockout significantly reduced the rupture rate of TAAD to 0 %. In addition, the protein levels of proinflammatory cytokines and matrix metalloproteinase 9 (MMP9) and ERS proteins were decreased in the aorta wall. Angptl8 shRNA decreased MMP9 and ERS protein levels in VSMCs in vitro. Overexpression of ANGPTL8 significantly increased the levels of ERS proteins and MMPs, while a PERK inhibitor significantly decreased the effects of ANGPTL8 in VSMCs. ANGPTL8 contributed to TAAD development by inducing ERS activation and degradation of extracellular matrix in the aorta wall. Inhibition of ANGPTL8 may therefore represent a new strategy for TAAD therapy.