ANGPTL8: An Important Regulator in Metabolic Disorders

Angiopoietin-2 and Angiopoietin-like Proteins with a Prospective Role in Predicting Diabetic Nephropathy

Angiopoietins are crucial growth factors for maintaining a healthy, functional endothelium. Patients with type 2 diabetes (T2D) exhibit significant levels of angiogenic markers, particularly Angiopoietin-2, which compromises endothelial integrity and is connected to symptoms of endothelial injury and failure. This report examines the levels of circulating angiopoietins in people with T2D and diabetic nephropathy (DN) and explores its link with ANGPTL proteins. We quantified circulating ANGPTL3, ANGPTL4, ANGPTL8, Ang1, and Ang2 in the fasting plasma of 117 Kuwaiti participants, of which 50 had T2D and 67 participants had DN. The Ang2 levels increased with DN (4.34 ± 0.32 ng/mL) compared with T2D (3.42 ± 0.29 ng/mL). This increase correlated with clinical parameters including the albumin-to-creatinine ratio (ACR) (r = 0.244, p = 0.047), eGFR (r = -0.282, p = 0.021), and SBP (r = -0.28, p = 0.024). Furthermore, Ang2 correlated positively to both ANGPTL4 (r = 0.541, p < 0.001) and ANGPTL8 (r = 0.41, p = 0.001). Multiple regression analysis presented elevated ANGPTL8 and ACRs as predictors for Ang2's increase in people with DN. In people with T2D, ANGPTL4 positively predicted an Ang2 increase. The area under the curve (AUC) in receiver operating characteristic (ROC) analysis of the combination of Ang2 and ANGPTL8 was 0.77 with 80.7% specificity. In conclusion, significantly elevated Ang2 in people with DN correlated with clinical markers such as the ACR, eGFR, and SBP, ANGPTL4, and ANGPTL8 levels. Collectively, this study highlights a close association between Ang2 and ANGPTL8 in a population with DN, suggesting them as DN risk predictors.

Association Between rs2278426 Polymorphism of the ANGPTL8 Gene and Polycystic Ovary Syndrome

Purpose

To study the relationship between the single nucleotide polymorphism (SNP) rs2278426 in the angiopoietin-like protein 8 gene (ANGPTL8) and polycystic ovary syndrome (PCOS).

Patients and methods

A total of 122 patients with PCOS and 108 controls were recruited for comparison of glucose, lipid, insulin, sex hormone, and ANGPTL8 levels. Polymerase chain reaction (PCR) and gene sequencing were performed for comparison of the frequency of the CC, CT, and TT rs2278426 genotypes and the rs2278426 allele distributions between the PCOS and control groups and between the obese and non-obese subgroups of the PCOS and control groups.

Results

The frequency of the T allele was significantly higher in the PCOS group than that in the controls (P = 0.037). In the dominant genetic model, the proportion of the CT+TT genotype in the PCOS group was significantly higher than that in the controls (P = 0.047). Subgroup analysis demonstrated that the T allele proportion was significantly higher in obese PCOS group than obese control group (P = 0.027). PCOS with the CT+TT genotype had significantly higher body mass index (BMI; P = 0.001), triglyceride (TG; P = 0.005), homeostasis model assessment of insulin resistance (HOMA-IR; P = 0.035), testosterone (P = 0.041), and ANGPTL8 (P = 0.037) levels and significantly lower high-density lipoprotein (HDL) levels (P = 0.025) than PCOS with the CC genotype. Obese PCOS group with the CT+TT genotype had significantly higher TG (P = 0.015), luteinizing hormone (LH; P = 0.030), fasting insulin (FINS; P = 0.039), HOMA-IR (P = 0.018), and ANGPTL8 (P = 0.049) levels than obese PCOS group with the CC genotype.

Conclusion

Polymorphisms of rs2278426 may induce glycolipid metabolic disorders by affecting ANGPTL8 levels and functions in Han Chinese females with obesity from the Shandong region, increasing the risk of PCOS in this population.

Role of the angiopoietin-like protein family in the progression of NAFLD

Non-alcoholic fatty liver disease (NAFLD) is the most frequent cause of chronic liver disease, with a range of conditions including non-alcoholic fatty liver, non-alcoholic steatohepatitis, cirrhosis, and hepatocellular carcinoma (HCC). Currently recognized as the liver component of the metabolic syndrome, NAFLD is intimately linked to metabolic diseases. Angiopoietin-like proteins (ANGPTLs) comprise a class of proteins that resemble angiopoietins structurally. It is closely related to obesity, insulin resistance and lipid metabolism, and may be the critical factor of metabolic syndrome. In recent years, many studies have found that there is a certain correlation between ANGPTLs and the occurrence and progression of NAFLD disease spectrum. This article reviews the possible mechanisms and roles of ANGPTL protein in the pathogenesis and progression of NAFLD.

Silencing ANGPTL8 reduces mouse preadipocyte differentiation and insulin signaling

ANGPTL8, expressed mainly in the liver and adipose tissue, regulates the activity of lipoprotein lipase (LPL) present in the extracellular space and triglyceride (TG) metabolism through its interaction with ANGPTL3 and ANGPTL4. Whether intracellular ANGPTL8 can also exert effects in tissues where it is expressed is uncertain. ANGPTL8 expression was low in preadipocytes and much increased during differentiation. To better understand the role of intracellular ANGPTL8 in adipocytes and assess whether it may play a role in adipocyte differentiation, we knocked down its expression in normal mouse subcutaneous preadipocytes. ANGPTL8 knockdown reduced adipocyte differentiation, cellular TG accumulation and also isoproterenol-stimulated lipolysis at day 7 of differentiation. RNA-Seq analysis of ANGPTL8 siRNA or control siRNA transfected SC preadipocytes on days 0, 2, 4 and 7 of differentiation showed that ANGPTL8 knockdown impeded the early (day 2) expression of adipogenic and insulin signaling genes, PPARγ, as well as genes related to extracellular matrix and NF-κB signaling. Insulin mediated Akt phosphorylation was reduced at an early stage during adipocyte differentiation. This study based on normal primary cells shows that ANGPTL8 has intracellular actions in addition to effects in the extracellular space, like modulating LPL activity. Preadipocyte ANGPTL8 expression modulates their differentiation possibly via changes in insulin signaling gene expression.

Predictive value of angiopoietin-like protein 8 in metabolic dysfunction-associated fatty liver disease and its progression: A case-control study

BACKGROUND

The prevalence of metabolic dysfunction-associated fatty liver disease (MAFLD) is rapidly increasing, currently affecting approximately 25% of the global population. Liver fibrosis represents a crucial stage in the development of MAFLD, with advanced liver fibrosis elevating the risks of cirrhosis and hepatocellular carcinoma. Simple serum markers are less effective in diagnosing liver fibrosis compared to more complex markers. However, imaging techniques like transient elastography face limitations in clinical application due to equipment and technical constraints. Consequently, it is imperative to identify a straightforward yet effective method for assessing MAFLD-associated liver fibrosis.

AIM

To investigate the predictive value of angiopoietin-like protein 8 (ANGPTL8) in MAFLD and its progression.

METHODS

We analyzed 160 patients who underwent abdominal ultrasonography in the Endocrinology Department, Xiaogan Central Hospital affiliated to Wuhan University of Science and Technology, during September 2021-July 2022. Using abdominal ultrasonography and MAFLD diagnostic criteria, among the 160 patients, 80 patients (50%) were diagnosed with MAFLD. The MAFLD group was divided into the liver fibrosis group (n = 23) and non-liver fibrosis group (n = 57) by using a cut-off fibrosis-4 index ≥ 1.45. Logistical regression was used to analyze the risk of MAFLD and the risk factors for its progression. Receiver operating characteristic curves were used to evaluate the predictive value of serum ANGPTL8 in MAFLD and its progression.

RESULTS

Compared with non-MAFLD patients, MAFLD patients had higher serum ANGPTL8 and triglyceride-glucose (TyG) index (both P < 0.05). Serum ANGPTL8 (r = 0.576, P < 0.001) and TyG index (r = 0.473, P < 0.001) were positively correlated with MAFLD. Serum ANGPTL8 was a risk factor for MAFLD [odds ratio (OR): 1.123, 95% confidence interval (CI): 1.066-1.184, P < 0.001). Serum ANGPTL8 and ANGPTL8 + TyG index predicted MAFLD [area under the curve (AUC): 0.832 and 0.886, respectively; both P < 0.05]. Compared with MAFLD patients without fibrosis, those with fibrosis had higher serum ANGPTL8 and TyG index (both P < 0.05), and both parameters were positively correlated with MAFLD-associated fibrosis. Elevated serum ANGPTL8 (OR: 1.093, 95%CI: 1.044-1.144, P < 0.001) and TyG index (OR: 2.383, 95%CI: 1.199-4.736, P < 0.013) were risk factors for MAFLD-associated fibrosis. Serum ANGPTL8 and ANGPTL8 + TyG index predicted MAFLD-associated fibrosis (AUC: 0.812 and 0.835, respectively; both P < 0.05).

CONCLUSION

The serum levels of ANGPTL8 are elevated and positively correlated with MAFLD. They can serve as predictors for the risk of MAFLD and liver fibrosis, with the ANGPTL8 + TyG index potentially exhibiting even higher predictive value.

Positive correlation of ANGPTL8 expression in human visceral adipose tissue with body mass index

BACKGROUND

Angiopoietin-like protein 8 (ANGPTL8) is an important regulator of lipid metabolism. We aimed to investigate the difference of ANGPTL8 expression in different depots of adipose tissues between individuals with and without obesity, and its correlation with various metabolic parameters.

METHODS

Subcutaneous (SAT) and visceral adipose tissue (VAT) samples were collected from patients who underwent bariatric or intra-abdominal surgery. Expression levels of ANGPTL8, monoglyceride lipase (MGL), monocyte chemoattractant protein-1 (MCP-1), leptin and adiponectin (APM1) were determined using real-time quantitative polymerase chain reaction. The correlation of ANGPTL8 expression with various metabolic parameters and other gene expression levels was analyzed using Person's correlation analysis. Logistic regression was used to establish a prediction model of obesity.

RESULTS

Totally 330 subjects (obese: 281, non-obese: 49) were recruited. ANGPTL8 expression in VAT was significantly higher in the obesity group than in the non-obesity group (P = 0.0096). ANGPTL8 expression in VAT was positively correlated with body mass index (BMI) (r = 0.1169, P < 0.05) and was independently associated with obesity (O.R., 1.246; 95 % C.I. 1.013-21.533, P = 0.038). We also found the gene expression of ANGPTL8 in SAT and VAT was negatively correlated with APM1 expression in respective SAT and VAT.

CONCLUSIONS

ANGPTL8 expression levels in VAT were higher in subjects with obesity, and positively correlated with BMI. This suggests a role of ANGPTL8 in the pathophysiology of obesity and may pave the way for novel treatment target of obesity.

Association of Genotypes of ANGPTL3 with Vitamin D and Calcium Concentration in Cardiovascular Disease

One of the leading causes of mortality worldwide is cardiovascular disease, which is influenced by some variables, including calcium and vitamin D. This study aimed to assess the relationship between Angiopoietin-Like 3 (ANGPTL3) gene polymorphisms with vitamin D and calcium levels in cardiovascular disease (CVD) patients. In this research, 1002 people participated. Participants' anthropometric parameters, and FBG, calcium, and vitamin D were assessed. Blood samples were used to extract DNA. Taqman®-based polymerase chain reaction (PCR) was used to conduct genetic analysis for the rs10789117 and rs17458195. Statistical analysis was applied to determine differences across subgroups and the relationship between polymorphisms and disease. Age, body mass index (BMI), fasting Blood Sugar (FBG), phenylalanine ammonia-lyase (PAL), and smoking history were significantly correlated with CVD. Vitamin D was statistically associated with rs10789117 and rs17458195 in non-CVD individuals. In the moderate group, individuals with the C allele in rs10789117 showed a tenfold increase in vitamin D deficiency compared to those with the A allele. However, in rs11207997, individuals with the T allele had 5 to 6 times higher vitamin D deficiency than those with the C allele in all groups. This research demonstrates the relationship between some ANGPTL3 gene polymorphisms and complement levels in CVD patients. It may be concluded that individuals carrying these variants would likely benefit from using vitamin D and calcium supplements to avoid CVD.

Urolithin C reveals anti-NAFLD potential via AMPK-ferroptosis axis and modulating gut microbiota

The pharmacology of urolithin C (UroC) on non-alcoholic fatty liver disease (NAFLD) is largely undetermined. We sought to investigate the potential for NAFLD improvement by administration of UroC and the underlying mechanisms. We verified the therapeutic effect of UroC on choline-deficient amino acid-defined high fat diet (CDAHFD) induced NAFLD mice via evaluating NAFLD activity score (NAS), AST, ALT, hepatic phosphorylated AMPK, and 4-hydroxynonenal. Oleic acid-induced AML12 cell was appraised by oil red staining and western blotting to explore the effect and mechanism of UroC in vitro. Transcriptional regulation of UroC was explored by liver RNA sequencing, gut microbiota composition was explored by 16SrRNA sequencing, and colorectal tight junctional proteins were detected by western blotting and immunohistochemistry. The detrimental effects of CDAHFD included the increased liver index, AST, ALT, hepatic 4-hydroxynonenal, impaired intestinal mucosal barrier, and most importantly, pathological damage in liver. Oral administration of UroC largely protected against these harmful alterations. Remarkably, both RNA sequencing and western blotting results indicated an activation in hepatic AMPK signaling pathway which was thought to inhibit ferroptosis response to UroC in vivo, while no change were found in AMPK-ferroptosis axis response to UroC in oleic acid-induced AML12 cells, hinted an indispensable linkage between UroC and hepatic AMPK, presumably the gut-liver axis. Furthermore, UroC could neither alleviate lipid deposition nor inhibit ferroptosis in vitro. The 16SrRNA showed UroC partially counteracted the dysbiosis induced by CDAHFD. Specifically, UroC reversed the elevated proportion of Firmicutes/Bacteroidota and enhanced the level of Parabacteroides goldsteinii and Lactobacillus vaginalis, which played a beneficial role in metabolic disorders. Oral administration of Urolithin C protected against the detrimental impact of CDAHFD via regulating AMPK-ferroptosis axis, maintaining intestinal mucosal barrier and counteracting gut dysbiosis.

Excessive Pregestational Weight and Maternal Obstetric Complications: The Role of Adipokines

There is a high frequency of overweight and obesity in women of reproductive age. Women who start pregnancy with overweight or obesity have an increased risk of developing maternal obstetric complications such as gestational hypertension, pre-eclampsia, gestational diabetes mellitus, postpartum hemorrhage, and requiring C-section to resolve the pregnancy with a higher risk of C-section surgical site infection. Excessive weight in pregnancy is characterized by dysregulation of adipokines, the functions of which partly explain the predisposition of pregnant women with overweight or obesity to these maternal obstetric complications. This review compiles, organizes, and analyzes the most recent studies on adipokines in pregnant women with excess weight and the potential pathophysiological mechanisms favoring the development of maternal pregnancy complications.

Targeted Metabolomics Analysis of Individuals Carrying the ANGPTL8 R59W Variant

ANGPTL8 is recognized as a regulator of lipid metabolism through its role in inhibiting lipoprotein lipase activity. ANGPTL8 gene variants, particularly rs2278426 leading to the R59W variant in the protein, have been associated with lipid traits in various ethnicities. We aimed to use metabolomics to understand the impact of the ANGPTL8 R59W variant on metabolites in humans. We used the Biocrates-p400 kit to quantify 408 plasma metabolites in 60 adult male Arab individuals from Kuwait and identify differences in metabolite levels between individuals carrying reference genotypes and those with carrier genotypes at ANGPTL8 rs2278426. Individuals with carrier genotypes (CT+TT) compared to those carrying the reference genotype (CC) showed statistically significant differences in the following metabolites: acylcarnitine (perturbs metabolic pathways), phosphatidylcholine (supports liver function and cholesterol levels), cholesteryl ester (brings chronic inflammatory response to lipoprotein depositions in arteries), α-aminoadipic acid (modulates glucose homeostasis), histamine (regulates glucose/lipid metabolism), sarcosine (links amino acid and lipid metabolism), diacylglycerol 42:1 (regulates homeostasis of cellular lipid stores), and lysophosphatidylcholine (regulates oxidative stress and inflammatory response). Functional aspects attributed to these metabolites indicate that the ANGPTL8 R59W variant influences the concentrations of lipid- and inflammation-related metabolites. This observation further highlights the role of ANGPTL8 in lipid metabolism.

Discordance between lipoprotein (a) and LDL-cholesterol levels in cardiovascular risk assessment in apparently healthy subjects

BACKGROUND AND AIMS

Lipoprotein(a) is a recognized independent cardiovascular risk factor and apolipoprotein B (apoB) level better reflects the risk than LDL-cholesterol. Despite this cardiovascular prediction mostly relies on traditional risk factors. We evaluated the association between Lp(a) and lipid biomarkers of cardiovascular risk in relation to age and sex in apparently healthy individuals.

METHODS AND RESULTS

422 presumably healthy subjects aged 19-84 were included. Lipid profile, Lp(a), apoB and small dense low-density lipoprotein cholesterol (sdLDL-C) were assayed. Subjects were divided at desirable cut-points of apoB and LDL-C. A group with elevated apoB (≥100 mg/dL) at low LDL-C (≤115 mg/dL) was appointed as high-risk and a group with low apoB but elevated LDL-C as low-risk. Significantly elevated triglycerides, TG/HDL-C and sdLDL-C were found in high risk group, but Lp(a) levels were comparable. TG/HDL-C was the best predictor of high risk with a very good diagnostic accuracy (AUC = 0.85), whereas Lp(a) had no discriminatory power. Women aged ≤40 with low LDL-C ≤ 100 mg/dL and elevated Lp(a) ≥ 40 mg/dL had higher levels of apoB and sdLDL-C (p = 0.002; p = 0.07) than those with Lp(a) < 40 mg/dL, which was not observed in men. In young females increase of LDL-C and apoB significantly raised the risk of elevated Lp(a).

CONCLUSIONS

Women younger than 40 with low LDL-C may be at increased cardiovascular risk associated with elevated Lp(a) and apolipoprotein B levels. Inclusion of Lp(a) and apoB in the routine lipid testing providing information on an individual level may improve the prediction of cardiovascular risk in primary prevention.

An Integrated Computational Analysis of High-Risk SNPs in Angiopoietin-like Proteins (ANGPTL3 and ANGPTL8) Reveals Perturbed Protein Dynamics Associated with Cancer

Angiopoietin-like proteins (ANGPTL) constitute a family of eight proteins (1-8) which play a pivotal role in the regulation of various pathophysiological processes. The current study sought to identify high-risk, "non-synonymous, single-nucleotide polymorphisms" (nsSNPs) in both ANGPTL3 and ANGPTL8 to evaluate the role that these nsSNPs play in various types of cancer. We retrieved a total of 301 nsSNPs from various databases; 79 of these candidates constitute high-risk nsSNPs. Moreover, we identified eleven high-risk nsSNPs that cause various types of cancer: seven candidates for ANGPTL3 (L57H, F295L, L309F, K329M, R332L, S348C, and G409R) and four candidates for ANGPTL8 (P23L, R85W, R138S, and E148D). Protein-protein interaction analysis revealed a strong association of ANGPTL proteins with several tumor-suppressor proteins such as ITGB3, ITGAV, and RASSF5. 'Gene-expression profiling interactive analysis' (GEPIA) showed that expression of ANGPTL3 is significantly downregulated in five cancers: sarcoma (SARC); cholangio carcinoma (CHOL); kidney chromophobe carcinoma (KICH); kidney renal clear cell carcinoma (KIRC); and kidney renal papillary cell carcinoma (KIRP). GEPIA also showed that expression of ANGPTL8 remains downregulated in three cancers: CHOL; glioblastoma (GBM); and breast invasive carcinoma (BRCA). Survival rate analysis indicated that both upregulation and downregulation of ANGPTL3 and ANGPTL8 leads to low survival rates in various types of cancer. Overall, the current study revealed that both ANGPTL3 and ANGPTL8 constitute potential prognostic biomarkers for cancer; moreover, nsSNPs in these proteins might lead to the progression of cancer. However, further in vivo investigation will be helpful to validate the role of these proteins in the biology of cancer.

Dual role of ANGPTL8 in promoting tumor cell proliferation and immune escape during hepatocarcinogenesis

The interplay between hepatocellular carcinoma (HCC) cells and the tumor microenvironment is essential for hepatocarcinogenesis, but their contributions to HCC development are incompletely understood. We assessed the role of ANGPTL8, a protein secreted by HCC cells, in hepatocarcinogenesis and the mechanisms through which ANGPTL8 mediates crosstalk between HCC cells and tumor-associated macrophages. Immunohistochemical, Western blotting, RNA-Seq, and flow cytometry analyses of ANGPTL8 were performed. A series of in vitro and in vivo experiments were conducted to reveal the role of ANGPTL8 in the progression of HCC. ANGPTL8 expression was positively correlated with tumor malignancy in HCC, and high ANGPTL8 expression was associated with poor overall survival (OS) and disease-free survival (DFS). ANGPTL8 promoted HCC cell proliferation in vitro and in vivo, and ANGPTL8 KO inhibited the development of HCC in both DEN-induced and DEN-plus-CCL4-induced mouse HCC tumors. Mechanistically, the ANGPTL8-LILRB2/PIRB interaction promoted polarization of macrophages to the immunosuppressive M2 phenotype in macrophages and recruited immunosuppressive T cells. In hepatocytes, ANGPTL8-mediated stimulation of LILRB2/PIRB regulated the ROS/ERK pathway and upregulated autophagy, leading to the proliferation of HCC cells. Our data support the notion that ANGPTL8 has a dual role in promoting tumor cell proliferation and immune escape during hepatocarcinogenesis.

Circulating ANGPTL8 as a Potential Protector of Metabolic Complications in Patients with Psoriasis

Angiopoietin-like protein 8 (ANGPTL8) exerts pleiotropic effects, taking part in lipid and carbohydrate metabolism, inflammation, hematopoiesis and oncogenesis. So far, the exact molecular targets of ANGPTL8 remain poorly defined. We aimed to evaluate the serum concentration of ANGPTL8 in individuals with psoriasis and examine how systemic therapy affects the concentration of ANGPTL8. The study enrolled 35 patients with plaque-type psoriasis that were followed for 3 months of treatment with methotrexate or acitretin, and 18 healthy volunteers without psoriasis as controls. Serum ANGPTL8 concentrations were analyzed by ELISA and differences between groups were determined using Student’s t-test or the Mann–Whitney test, while correlations were assessed using Spearman’s rank test. The average concentration of ANGPTL8 differed significantly between the psoriasis group (before and after therapy) and the control group (p < 0.05). Significant negative correlations between ANGPTL8 and total cholesterol and LDL levels were noted (both p < 0.05). A significant increase in ANGPTL8 concentration was observed after acitretin (p < 0.05), whereas in patients treated with methotrexate the ANGPTL8 did not change significantly (p > 0.05). Additionally, a negative, statistically significant correlation with PASI was found after treatment (p < 0.05). Based on our study, it appears that elevated levels of ANGPTL8 may reduce the likelihood of atherogenic dyslipidemia in individuals with psoriasis, and treatment for psoriasis may impact the protective effects of ANGPTL8.

Genetic diversity and signatures of selection in BoHuai goat revealed by whole-genome sequencing

BACKGROUND

Cross breeding is an important way to improve livestock performance. As an important livestock and poultry resource in Henan Province of China, Bohuai goat was formed by crossing Boer goat and Huai goat. After more than 20 years of breeding, BoHuai goats showed many advantages, such as fast growth, good reproductive performance, and high meat yield. In order to better develop and protect Bohuai goats, we sequenced the whole genomes of 30 BoHuai goats and 5 Huai goats to analyze the genetic diversity, population structure and genomic regions under selection of BoHuai goat. Furthermore, we used 126 published genomes of world-wide goat to characterize the genomic variation of BoHuai goat.

RESULTS

The results showed that the nucleotide diversity of BoHuai goats was lower and the degree of linkage imbalance was higher than that of other breeds. The analysis of population structure showed that BoHuai goats have obvious differences from other goat breeds. In addition, the BoHuai goat is more closely related to the Boer goat than the Huai goat and is highly similar to the Boer goat. Group by selection signal in the BoHuai goat study, we found that one region on chromosome 7 shows a very strong selection signal, which suggests that it could well be the segment region under the intense artificial selection results. Through selective sweeps, we detected some genes related to important traits such as lipid metabolism (LDLR, STAR, ANGPTL8), fertility (STAR), and disease resistance (CD274, DHPS, PDCD1LG2).

CONCLUSION

In this paper, we elucidated the genomic variation, ancestry composition, and selective signals related to important economic traits in BoHuai goats. Our studies on the genome of BoHuai goats will not only help to understand the characteristics of the crossbred but also provide a basis for the improvement of cross-breeding programs.

Human CYP2B6 produces oxylipins from polyunsaturated fatty acids and reduces diet-induced obesity

Multiple factors in addition to over consumption lead to obesity and non-alcoholic fatty liver disease (NAFLD) in the United States and worldwide. CYP2B6 is the only human detoxification CYP whose loss is associated with obesity, and Cyp2b-null mice show greater diet-induced obesity with increased steatosis than wildtype mice. However, a putative mechanism has not been determined. LC-MS/MS revealed that CYP2B6 metabolizes PUFAs, with a preference for metabolism of ALA to 9-HOTrE and to a lesser extent 13-HOTrE with a preference for metabolism of PUFAs at the 9- and 13-positions. To further study the role of CYP2B6 in vivo, humanized-CYP2B6-transgenic (hCYP2B6-Tg) and Cyp2b-null mice were fed a 60% high-fat diet for 16 weeks. Compared to Cyp2b-null mice, hCYP2B6-Tg mice showed reduced weight gain and metabolic disease as measured by glucose tolerance tests, however hCYP2B6-Tg male mice showed increased liver triglycerides. Serum and liver oxylipin metabolite concentrations increased in male hCYP2B6-Tg mice, while only serum oxylipins increased in female hCYP2B6-Tg mice with the greatest increases in LA oxylipins metabolized at the 9 and 13-positions. Several of these oxylipins, specifically 9-HODE, 9-HOTrE, and 13-oxoODE, are PPAR agonists. RNA-seq data also demonstrated sexually dimorphic changes in gene expression related to nuclear receptor signaling, especially CAR > PPAR with qPCR suggesting PPARγ signaling is more likely than PPARα signaling in male mice. Overall, our data indicates that CYP2B6 is an anti-obesity enzyme, but probably to a lesser extent than murine Cyp2b's. Therefore, the inhibition of CYP2B6 by xenobiotics or dietary fats can exacerbate obesity and metabolic disease potentially through disrupted PUFA metabolism and the production of key lipid metabolites.

The Effect of Four Weeks of Long-Term Endurance Training with and Without Propolis Supplementation on Serum Levels of Betatrophin/ANGPTL8 in Male Athletes

Background: Betatrophin/angiopoietin-like protein (ANGPTL8) is defined as an adipokine that regulates blood glucose and triglyceride levels. Objectives: This study aimed to evaluate the effect of propolis supplementation for the first time on serum levels of the hormone betatrophin, as a drug target in the treatment of dyslipidemia, in male endurance athletes for four weeks. Methods: 44 male athletes with an average age of 22 ± 3 years, a height of 177.5 ± 6.5 cm, and a weight of 76 ± 6 kg were selected in Qazvin. They were randomly divided into four groups: Supplementation, placebo, physical activity, and control. The supplementation and placebo groups received two 500 mg tablets of propolis and cellulose (in terms of shape and color, are similar to the original supplement and have no properties, flavor, and aroma) once after lunch and once after dinner, respectively. The drug treatment lasted for four weeks. The athletes' weight and serum levels of betatrophin were measured at the beginning and the end of 4 weeks of treatment. The ELISA method was used to assess the serum concentration of betatrophin. Analyzes were performed by the ANCOVA method. Results: The results showed that the long-term endurance training plus propolis supplementation would result in significant changes in the betatrophin serum levels and weight in participants (P = 0.001), but in the athletes without supplementation, these changes were not significant (P > 0.05). Conclusions: The results indicated that betatrophin serum levels in endurance athletes are increased by propolis supplementation, and their weight is decreased.

Differences in Adipose Gene Expression Profiles between Male and Female Even Reindeer (Rangifer tarandus) in Sakha (Yakutia)

Reindeer are native to harsh northern Eurasian environments which are characterized by long and cold winters, short summers, and limited pasture vegetation. Adipose tissues play a significant role in these animals by modulating energy metabolism, immunity, and reproduction. Here, we have investigated the transcriptome profiles of metacarpal, perirenal, and prescapular adipose tissues in Even reindeer and searched for genes that were differentially expressed in male and female individuals. A total of 15,551 genes were expressed, where the transcriptome profile of metacarpal adipose tissue was found to be distinct from that of perirenal and prescapular adipose tissues. Interestingly, 10 genes, including PRDM9, which is known to have an important role in adaptation and speciation in reindeer, were always upregulated in all three tissues of male reindeer.

Serum ANGPTL8 and ANGPTL3 as Predictors of Triglyceride Elevation in Adult Women

Angiopoietin-like proteins ANGPTL3 and ANGPTL8 have been shown to inhibit lipoprotein lipase, and thus regulate triglyceride level in the circulation. Whether the regulation of lipid metabolism by ANGPTLs is affected by the menopausal status remains unclear. We aimed to assess the relationships between serum ANGPTL3 and ANGPTL8 and atherogenic biomarkers in presumably healthy women during ageing. The study group included 94 women of whom 31 were premenopausal (PRE ≤ 40 years) and 37 were postmenopausal (POST ≥ 52 years). Atherogenic lipid and non-lipid biomarkers and ANGPTLs (ANGPTL3, ANGPTL8) were assayed in serum samples. TG/HDL-C index, non-HDL-cholesterol, remnant cholesterol concentrations, and BMI were calculated. Median levels of ANGPTL3 and concentrations of lipid biomarkers were significantly higher in POST comparing to PRE but ANGPTL8 levels were not different. In PRE, ANGPTL8 levels correlated significantly with TG and TG/HDL-C index while there were no correlations between ANGPTL3 and these biomarkers. In POST both ANGPTLs correlated with TG, sdLDL-C, and TG/HDL-C. ANGPTL8 and sd-LDL-C were the most significant predictors of early triglyceride elevation > 100 mg/dL (1.13 mmol/L) in the whole group and POST whereas the prediction power of ANGPTL3 was negligible in the whole group and non-significant in the subgroups. We demonstrated a significant positive correlation of ANGPTL3 with age category which predisposes to postmenopause. Despite the increase in ANGPTL3 level with ageing the ANGPTL3/ANGPL8 ratio was maintained. In conclusion, ANGPTL8 predicts the early triglyceride elevation better than ANGPTL3, especially in postmenopausal women. The association of ANGPTL3 with triglyceride levels is weaker than ANGPTL8 and depends on menopausal status. We suggest that the choice for the best efficient treatment of dyslipidemia with new inhibitors of angiopoietin-like proteins may depend on the menopausal status.

New Insights into Adipokines in Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is the most common metabolic disorder of pregnancy and has considerable short- and long-term consequences for the health of both the mother and the newborn. Within its pathophysiology, genetic, nutritional, epigenetic, immunological, and hormonal components have been described. Within the last two items, it is known that different hormones and cytokines secreted by adipose tissue, known collectively as adipokines, are involved in the metabolic alterations underlying GDM. Although the maternal circulating profile of adipokines in GDM has been extensively studied, and there are excellent reviews on the subject, it is in recent years that more progress has been made in the study of their expression in visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), placenta, and their concentrations in the umbilical circulation. Thus, this review compiles and organizes the most recent findings on the maternal and umbilical circulating profile and the levels of expression of adipokines in VAT, SAT, and placenta in GDM.

RNA-Seq Analysis of Protection against Chronic Alcohol Liver Injury by Rosa roxburghii Fruit Juice (Cili) in Mice

Rosa roxburghii Tratt. fruit juice (Cili) is used as a medicinal and edible resource in China due to its antioxidant and hypolipidemic potentials. The efficacy of Cili in protecting alcohol-induced liver injury and its underlying mechanism was investigated. C57BL/6J mice received a Lieber-DeCarli liquid diet containing alcohol to produce liver injury. After the mice were adapted gradually to 5% alcohol, Cili (4 mL and 8 mL/kg/day for 4 weeks) were gavaged for treatment. The serum enzyme activities, triglyceride levels, histopathology and Oil-red O staining were examined. The RNA-Seq and qPCR analyses were performed to determine the protection mechanisms. Cili decreased serum and liver triglyceride levels in mice receiving alcohol. Hepatocyte degeneration and steatosis were improved by Cili. The RNA-Seq analyses showed Cili brought the alcohol-induced aberrant gene pattern towards normal. The qPCR analysis verified that over-activation of CAR and PXR (Cyp2a4, Cyp2b10 and Abcc4) was attenuated by Cili. Cili alleviated overexpression of oxidative stress responsive genes (Hmox1, Gsta1, Gstm3, Nqo1, Gclc, Vldlr, and Cdkn1a), and rescued alcohol-downregulated metabolism genes (Angptl8, Slc10a2, Ces3b, Serpina12, C6, and Selenbp2). Overall, Cili was effective against chronic alcohol liver injury, and the mechanisms were associated with decreased oxidative stress, improved lipid metabolism through modulating nuclear receptor CAR-, PXR-and Nrf2-mediated pathways.

Lessons learned from the evinacumab trials in the treatment of homozygous familial hypercholesterolemia

Homozygous familial hypercholesterolemia (HoFH) is a life-threatening disease characterized by extremely elevated LDL cholesterol (LDL-C) levels which result in premature atherosclerotic cardiovascular disease. As conventional lipid-lowering therapies, which mainly depend on LDL receptors for LDL particle clearance, remain insufficient for reaching the recommended LDL-C levels in HoFH, agents acting independently of LDL receptors, such as ANGPTL3 inhibitors, constitute a promising target. Evinacumab, a monoclonal antibody directed against ANGPTL3, was approved in the USA in 2021 for treating patients with HoFH. Evinacumab has shown an adequate safety profile with strong LDL-lowering efficacy. This review highlights the development path of evinacumab and provides insight on the lessons learned from trials as well as the hurdles facing accessibility.

Insulin action and resistance are dependent on a GSK3β-FBXW7-ERRα transcriptional axis

Insulin resistance, a harbinger of the metabolic syndrome, is a state of compromised hormonal response resulting from the dysregulation of a wide range of insulin-controlled cellular processes. However, how insulin affects cellular energy metabolism via long-term transcriptional regulation and whether boosting mitochondrial function alleviates insulin resistance remains to be elucidated. Herein we reveal that insulin directly enhances the activity of the nuclear receptor ERRα via a GSK3β/FBXW7 signaling axis. Liver-specific deletion of GSK3β or FBXW7 and mice harboring mutations of ERRα phosphosites (ERRα3SA) co-targeted by GSK3β/FBXW7 result in accumulated ERRα proteins that no longer respond to fluctuating insulin levels. ERRα3SA mice display reprogrammed liver and muscle transcriptomes, resulting in compromised energy homeostasis and reduced insulin sensitivity despite improved mitochondrial function. This crossroad of insulin signaling and transcriptional control by a nuclear receptor offers a framework to better understand the complex cellular processes contributing to the development of insulin resistance.

Correlation between betatrophin/angiogenin-likeprotein3/lipoprotein lipase pathway and severity of coronary artery disease in Kazakh patients with coronary heart disease

BACKGROUND

The results of previous animal experiments and clinical studies have shown that there is a correlation between expression of betatrophin and blood lipid levels. However, there are still differences studies on the correlation and interaction mechanism between betatrophin, angiogenin-likeprotein3 (ANGPTL3) and lipoprotein lipase (LPL). In our previous studies, we found an increase in serum ANGPTL3 Levels in Chinese patients with coronary heart disease (CHD). Therefore, we retrospectively studied Kazakh CHD patients.

AIM

To explore the correlation between the betatrophin/ANGPTL3/LPL pathway and severity of coronary artery disease (CAD) in patients with CHD.

METHODS

Nondiabetic patients diagnosed with CHD were selected as the case group; 79 were of Kazakh descent and 72 were of Han descent. The control groups comprised of 61 Kazakh and 65 Han individuals. The serum levels of betatrophin and LPL were detected by enzyme-linked immunosorbent assay (ELISA), and the double antibody sandwich ELISA was used to detect serum level of ANGPTL3. The levels of triglycerides, total cholesterol, and fasting blood glucose in each group were determined by an automatic biochemical analyzer. At the same time, the clinical baseline data of patients in each group were included.

RESULTS

Betatrophin, ANGPTL3 and LPL levels of Kazakh patients were significantly higher than those of Han patients (P = 0.031, 0.038, 0.021 respectively). There was a positive correlation between the Gensini score and total cholesterol (TC), triglycerides (TG), low- density lipoprotein cholesterol (LDL-C), betatrophin, and LPL in Kazakh patients (r = 0.204, 0.453, 0.352, 0.471, and 0.382 respectively), (P = 0.043, 0.009, 0.048, 0.001, and P < 0.001 respectively). A positive correlation was found between the Gensini score and body mass index (BMI), TC, TG, LDL-C, LPL, betatrophin in Han patients (r = 0.438, 0.195, 0.296, 0.357, 0.328, and 0.446 respectively), (P = 0.044, 0.026, 0.003, 0.20, 0.004, and P < 0.001). TG and betatrophin were the risk factors of coronary artery disease in Kazakh patients, while BMI and betatrophin were the risk factors in Han patients.

CONCLUSION

There was a correlation between the betatrophin/ANGPTL3/LPL pathway and severity of CAD in patients with CHD.

Endothelial cell-derived angiopoietin-like protein 2 supports hematopoietic stem cell activities in bone marrow niches

Endothelial cell-derived ANGPTL2 is important for the maintenance of HSC activities in bone marrow niches.

ANGPTL2-mediated signaling pathways enhance PPARδ expression to transactivate G0s2 to sustain HSC activities.

Bone marrow niche cells have been reported to fine-tune hematopoietic stem cell (HSC) stemness via direct interaction or secreted components. Nevertheless, how niche cells control HSC activities remains largely unknown. We previously showed that angiopoietin-like protein 2 (ANGPTL2) can support the ex vivo expansion of HSCs by binding to human leukocyte immunoglobulin-like receptor B2. However, how ANGPTL2 from specific niche cell types regulates HSC activities under physiological conditions is still not clear. Herein, we generated an Angptl2-flox/flox transgenic mouse line and conditionally deleted Angptl2 expression in several niche cells, including Cdh5⁺ or Tie2⁺ endothelial cells, Prx1⁺ mesenchymal stem cells, and Pf4⁺ megakaryocytes, to evaluate its role in the regulation of HSC fate. Interestingly, we demonstrated that only endothelial cell-derived ANGPTL2 and not ANGPTL2 from other niche cell types plays important roles in supporting repopulation capacity, quiescent status, and niche localization. Mechanistically, ANGPTL2 enhances peroxisome-proliferator-activated receptor D (PPARD) expression to transactivate G0s2 to sustain the perinuclear localization of nucleolin to prevent HSCs from entering the cell cycle. These findings reveal that endothelial cell-derived ANGPTL2 serves as a critical niche component to maintain HSC stemness, which may benefit the understanding of stem cell biology in bone marrow niches and the development of a unique strategy for the ex vivo expansion of HSCs.

Hepatokines and Non-Alcoholic Fatty Liver Disease: Linking Liver Pathophysiology to Metabolism

The liver plays a key role in maintaining energy homeostasis by sensing and responding to changes in nutrient status under various metabolic conditions. Recently highlighted as a major endocrine organ, the contribution of the liver to systemic glucose and lipid metabolism is primarily attributed to signaling crosstalk between multiple organs via hepatic hormones, cytokines, and hepatokines. Hepatokines are hormone-like proteins secreted by hepatocytes, and a number of these have been associated with extra-hepatic metabolic regulation. Mounting evidence has revealed that the secretory profiles of hepatokines are significantly altered in non-alcoholic fatty liver disease (NAFLD), the most common hepatic manifestation, which frequently precedes other metabolic disorders, including insulin resistance and type 2 diabetes. Therefore, deciphering the mechanism of hepatokine-mediated inter-organ communication is essential for understanding the complex metabolic network between tissues, as well as for the identification of novel diagnostic and/or therapeutic targets in metabolic disease. In this review, we describe the hepatokine-driven inter-organ crosstalk in the context of liver pathophysiology, with a particular focus on NAFLD progression. Moreover, we summarize key hepatokines and their molecular mechanisms of metabolic control in non-hepatic tissues, discussing their potential as novel biomarkers and therapeutic targets in the treatment of metabolic diseases.

Metabolism of Triglyceride-Rich Lipoproteins

Triglycerides are critical lipids as they provide an energy source that is both compact and efficient. Due to its hydrophobic nature triglyceride molecules can pack together densely and so be stored in adipose tissue. To be transported in the aqueous medium of plasma, triglycerides have to be incorporated into lipoprotein particles along with other components such as cholesterol, phospholipid and associated structural and regulatory apolipoproteins. Here we discuss the physiology of normal triglyceride metabolism, and how impaired metabolism induces hypertriglyceridemia and its pathogenic consequences including atherosclerosis. We also discuss established and novel therapies to reduce triglyceride-rich lipoproteins.

Adipose gene expression profiles reveal insights into the adaptation of northern Eurasian semi-domestic reindeer (Rangifer tarandus)

Reindeer (Rangifer tarandus) are semi-domesticated animals adapted to the challenging conditions of northern Eurasia. Adipose tissues play a crucial role in northern animals by altering gene expression in their tissues to regulate energy homoeostasis and thermogenic activity. Here, we perform transcriptome profiling by RNA sequencing of adipose tissues from three different anatomical depots: metacarpal (bone marrow), perirenal, and prescapular fat in Finnish and Even reindeer (in Sakha) during spring and winter. A total of 16,212 genes are expressed in our data. Gene expression profiles in metacarpal tissue are distinct from perirenal and prescapular adipose tissues. Notably, metacarpal adipose tissue appears to have a significant role in the regulation of the energy metabolism of reindeer in spring when their nutritional condition is poor after winter. During spring, genes associated with the immune system are upregulated in the perirenal and prescapular adipose tissue. Blood and tissue parameters reflecting general physiological and metabolic status show less seasonal variation in Even reindeer than in Finnish reindeer. This study identifies candidate genes potentially involved in immune response, fat deposition, and energy metabolism and provides new information on the mechanisms by which reindeer adapt to harsh arctic conditions.

Association of Circulating ANGPTL8 Levels With Renal Dysfunction: A Case-Control Study

Background: Chronic kidney disease (CKD) is recognized as a major public health problem with high morbidity and mortality worldwide. Recently, angiopoietin-like protein 8 (ANGPTL8) was found to regulate lipid metabolism. Previous studies suggested that serum ANGPTL8 levels increased in patients with diabetes, especially in diabetic patients with albuminuria. This study aimed to investigate the association between circulating levels of ANGPTL8 and kidney function in the general population. Methods: The subjects were patients with renal dysfunction [estimated glomerular filtration rate (eGFR) <60/min/1.73 m²] from Risk Evaluation of cAncers in Chinese diabeTic Individuals: a lONgitudinal study (the REACTION study). Each case was matched by age, sex, and body mass index (BMI) with one control whose eGFR was ≥ 90 ml/min/1.73 m². The case and control groups were compared using a paired t-test. Binary logistic regression analysis was used to calculate the odds ratio (OR) of renal dysfunction (RD). Results: Among 135 case-control pairs, circulating ANGPTL8 levels were elevated in patients with RD compared to control subjects [799.96 (410.12-1086.44) vs. 609.58 (365.13-740.06) pg/ml, p < 0.05]. Partial correlations showed that ANGPTL8 levels were negatively correlated with eGFR (r = -0.26, p < 0.05). Multivariable-adjusted binary logistic regression analysis showed that elevated ANGPTL8 levels were associated with an increased risk of RD (OR in quartile 4 vs. 1, 3.80; 95% CI, 1.71-8.41). Interestingly, the association between ANGPTL8 levels and RD was consistent with the overall findings in both nondiabetic individuals (OR, 1.44; 95% CI, 1.09 to 1.91) and diabetic patients (OR, 2.71; 95% CI, 1.13-6.49) in the subgroup analyses. Furthermore, the estimates for this association were also significant in females (OR, 2.12; 95% CI, 1.33-3.37), individuals aged > 60 years (OR, 1.55; 95% CI, 1.16-2.07), individuals with a BMI <24 (OR, 1.66; 95% CI, 1.16-2.39), and individuals without hyperlipidaemia (OR, 1.61; 95% CI, 1.16-2.23) (all p-values <0.05). Conclusion: Elevated circulating ANGPTL8 levels were associated with increased risk of RD in the general population, especially among females, individuals aged > 60 years, individuals with a BMI < 24, individuals without diabetes mellitus, individuals with diabetes mellitus (DM), and individuals without hyperlipidaemia. This finding implies that ANGPTL8 may play a role in the pathological process of RD.

Association of ANGPTL8 and Resistin With Diabetic Nephropathy in Type 2 Diabetes Mellitus

Background

Previous studies showed altered angiopoietin-like protein-8 (ANGPTL-8) and resistin circulating levels in type 2 diabetes mellitus (T2DM). Whether or not the alteration in ANGPTL-8 and resistin level can be a predictive maker for increased diabetic nephropathy risk remains unclear.

Aim

To Investigate the possible association of ANGPTL-8 and resistin with DN, and whether this association is affected by NAFLD status.

Methods

A total of 278 T2DM patients were enrolled. Serum levels of ANGPTL8, resistin, BMI, blood pressure, duration of diabetes, glycosylated hemoglobin (HbA1c), fasting blood glucose (FPG), hypersensitive C-reactive protein (hs-CRP), lipid profile, liver, and kidney function tests were assessed. The relationship between DN with ANGPTL8 and resistin was analyzed in the unadjusted and multiple-adjusted regression models.

Results

Serum levels of ANGPTL8 and resistin were significantly higher in DN compared with T2DM subjects without DN (respectively; P <0.001), especially in non-NAFLD populations. ANGPTL8 and resistin showed positive correlation with hs-CRP (respectively; P<0.01), and negative correlation with estimated GFR (eGFR) (respectively; P=<0.001) but no significant correlation to HOMA-IR(respectively; P>0.05). Analysis showed ANGPTL8 levels were positively associated with resistin but only in T2DM patients with DN(r=0.1867; P<0.05), and this significant correlation disappeared in T2DM patients without DN. After adjusting for confounding factors, both ANGPTL8(OR=2.095, 95%CI 1.253-3.502 P=0.005) and resistin (OR=2.499, 95%CI 1.484-4.208 P=0.001) were risk factors for DN. Data in non-NAFLD population increased the relationship between ANGPTL8 (OR=2.713, 95% CI 1.494-4.926 P=0.001), resistin (OR=4.248, 95% CI 2.260-7.987 P<0.001)and DN. The area under the curve (AUC) on receiver operating characteristic (ROC) analysis of the combination of ANGPTL8 and resistin was 0.703, and the specificity was 70.4%. These data were also increased in non-NAFLD population, as the AUC (95%CI) was 0.756, and the specificity was 91.2%.

Conclusion

This study highlights a close association between ANGPTL8, resistin and DN, especially in non-NAFLD populations. These results suggest that ANGPTL-8 and resistin may be risk predictors of DN.

Angiopoietin-like 8 (ANGPTL8) as a potential predictor of NAFLD in paediatric patients with Prader-Willi Syndrome

PURPOSE

Angiopoietin-like 8 (ANGPTL8) is a liver- and adipose tissue-produced protein that predicts non-alcoholic fatty liver disease (NAFLD) and altered metabolic homeostasis in the general population as well as in persons with common and genetic obesity, including the Prader-Willi syndrome (PWS). However, its metabolic correlate in paediatric patients with respect to PWS is unknown.

METHODS

This cross-sectional study investigated circulating ANGPTL8 and adipocytokines levels in 28 PWS and 28 age-, sex- and BMI-matched children and adolescents (age, 7.0-17.8y) in relation to NAFLD and metabolic homeostasis assessed by OGTT, paediatric metabolic index (PMI) and fatty liver index (FLI), liver ultrasonography (US), as well as dual-energy X-ray absorptiometry (DEXA) for analysis of fat (FM) and fat-free mass (FFM).

RESULTS

At the set level of significance, PWS children showed lower values of FFM (p < 0.01) but healthier insulin profiles (p < 0.01) and PMI values (p < 0.05) than matched controls. By US, the prevalence of NAFLD was similar between groups but less severe in PWS than controls. Analysis of ANGPTL8 levels showed no difference between groups, yet only in PWS ANGPTL8 levels were associated with ALT levels, FLI values and NAFLD. In stepwise multivariable regression analysis on merged data, ANGPTL8 levels were independently predicted by BMI SDS, leptin levels and NAFLD.

CONCLUSION

ANGPTL8 levels are similar in PWS and controls and, overall, they are directly associated with the presence and severity of NAFLD in patients with PWS.

Angiopoietin-like proteins in atherosclerosis

Atherosclerosis, as a chronic inflammatory disease within the arterial wall, is a leading cause of morbidity and mortality worldwide due to its role in myocardial infarction, stroke and peripheral artery disease. Additional evidence is emerging that the angiopoietin-like (ANGPTL) family of proteins participate in the pathology of this disease process via endothelial dysfunction, inflammation, dyslipidemia, calcification, foam cell formation and platelet activation. This review summarizes current knowledge on the ANGPTL family of proteins in atherosclerosis related pathological processes. Moreover, the potential value of ANGPTL family proteins as predictive biomarkers in atherosclerosis is discussed. Given the attractive role of ANGPTL3, ANGPTL4, ANGPTL8 in atherosclerotic dyslipidemia via regulation of lipoprotein lipase (LPL), antisense oligonucleotide or/and monoclonal antibody-based inactivation of these proteins represent potential atherosclerotic therapies.

New emerging roles of the novel hepatokine SERPINB1 in type 2 diabetes mellitus: Crosstalk with β-cell dysfunction and dyslipidemia

Diabetes mellitus (DM) is a devastating metabolic disease. Recently, the cross-talk between insulin-secreting-β-cells and various organs has sparked much interest. SerpinB1 emerged as a novel hepatokine inducing β-cell proliferation. However, its role in type-2-DM (T2DM) patients has not been adequately studied. This study was designed to investigate its circulating levels in subjects with/without T2DM, and to study its association with β-cell function, as well as various glycemic-control and lipid-profile parameters. Anthropometric data and biochemical markers including fasting plasma glucose (FPG), HbA_1C % and lipid profile parameters were measured in 55 T2DM patients, as well as 30 healthy nondiabetic subjects. Serum serpinB1, insulin and C-peptide levels were measured by ELISA. The homeostasis model assessment of both β-cell function (HOMA2-β%) and insulin resistance (HOMA-IR) were calculated. SerpinB1 levels were found to be significantly lower in T2DM patients 0.7 (0.2-12.4) ng/mL, compared to nondiabetic subjects 1.2 (0.94-24) ng/mL, P < 0.001, regardless of glycemic control, obesity, or insulin resistance. Additionally, serpinB1 levels were found to be positively associated with C-peptide, HOMA2-β% in all subjects; and BMI only in non-DM subjects; while negatively associated with FPG, HbA_1C% and lipid-profile parameters. Higher serum serpinB1 levels were found to be associated with lower susceptibility for T2DM. Conclusively, serpinB1 is associated with various aspects of β-cell dysfunction, glycemic-control, and dyslipidemia with a possible role in β-cell compensation in obese nondiabetic subjects. The results of the current study shed lights on potential novel roles of serpinB1 in T2DM besides its action as an inducer for β-cell proliferation.

ANGPTL8 roles in proliferation, metabolic diseases, hypothyroidism, polycystic ovary syndrome, and signaling pathways

A new and atypical member of the ANGPTL family is angiopoietin-like protein 8 (ANGPTL8). This newly discovered hormone is a drug target that can be used to treat diabetes and dyslipidemia. The protein, as a hepatocyte-derived circulating factor, can control the triglyceride level of plasma. ANGPTL8 is significantly associated with inflammation and metabolic syndrome consequences such as obesity, diabetes, hypothyroidism, and PCOS. ANGPTL8 gene has four exons encoding a 22/5 kDa weight of 198 amino acid polypeptides. A highly preserved ANGPTL8 gene among mammals exhibits the essential hormone functions of ANGPTL8. Nevertheless, the physiological function of this hormone in the body is poorly understood. Studies published in PubMed (2008-2020), Google Scholar (2004-2020), and Scopus (2004-2020) databases of clinical trials were reviewed. This analysis is aimed at collecting information on ANGPTL8. The emphasis of this review was on gathering information about the role of ANGPTL8 in the metabolism of glucose and lipids and cell proliferation. It addition to the different roles of ANGPTL8 in diabetes and lipid metabolism, this review emphasized on the protein role in signaling pathways. The study also proposes the signaling pathways that may be considered as a new target for treatment.

ANGPLT3 in cardio-metabolic disorders

Dyslipidemia is associated with numerous health problems that include the combination of insulin resistance, hypertension and obesity, which is always grouped together asmetabolic syndrome. Given that metabolic syndrome leads to a high mortality and poses serious risks to human health worldwide, it is vital to explore the mechanisms whereby dyslipidemia modulates the risk and the severity of cardio-metabolic disorders. Recently, a specific secretory protein family, named angiopoietin-like protein (ANGPTL), is considered as one of the significant biomarkers which facilitate the development of angiogenesis. Among the eight proteins of ANGPTL family, ANGPTL3 has been demonstrated as an essential modulator of lipid catabolism within circulation by inhibiting the activity of lipoprotein lipase (LPL) and endothelial lipase (EL). Consistent with these notions, mice with ANGPTL3 gene-deficiency presented reduced circulating levels of low density lipoprotein cholesterol (LDL-C) and lower risk of atherosclerosis. On the other hand, participants carrying homozygous loss-of function (LOF) mutation in ANGPTL3 gene also displayed lower circulating LDL-C levels and atherosclerotic risk. In the current review, we summarized the recent understanding of ANGPTL3 in controlling the risk and the development of dyslipidemia and its related cardio-metabolic disorders. Moreover, we also provided the perspectives which potentially suggested that ANGPTL3 could be considered as a promising target in treating metabolic syndrome.

Decreased serum betatrophin may correlate with the improvement of obstructive sleep apnea after Roux-en-Y Gastric Bypass surgery

Obesity is strongly correlated with obstructive sleep apnea (OSA), and bariatric surgery can effectively treat obesity and alleviate OSA. However, the contributing factors are still unclear. We aimed to explore the relationship between betatrophin and OSA in patients undergoing Roux-en-Y gastric bypass (RYGB) surgery. Our study consisted of thirty-seven individuals with OSA and type 2 diabetes (16 males, 21 females) undergoing RYGB surgery. The polysomnography test, anthropometric results, serum betatrophin, and abdominal magnetic resonance images were evaluated both before and 1 year after RYGB surgery. Factors that may correlate with the alleviation of OSA were investigated. In our study, RYGB surgery significantly decreased apnea hypopnea index (AHI) and serum betatrophin concentration (p < 0.001). The abdominal visceral fat area, subcutaneous fat area and HOMA-IR were also significantly decreased (p < 0.001). The preoperative AHI, postoperative AHI and the change in AHI were significantly correlated with the preoperative betatrophin, postoperative betatrophin and the change in betatrophin, respectively (p < 0.05). These correlations were still significant after adjustment for other risk factors. The change in betatrophin was also independently associated with the change in minimum oxygen saturation (p < 0.001). Our data might indicate that serum betatrophin was significantly independently correlated with the improvement of OSA after bariatric surgery.

Lipoprotein Lipase and Its Regulators: An Unfolding Story

Lipoprotein lipase (LPL) is one of the most important factors in systemic lipid partitioning and metabolism. It mediates intravascular hydrolysis of triglycerides packed in lipoproteins such as chylomicrons and very-low-density lipoprotein (VLDL). Since its initial discovery in the 1940s, its biology and pathophysiological significance have been well characterized. Nonetheless, several studies in the past decade, with recent delineation of LPL crystal structure and the discovery of several new regulators such as angiopoietin-like proteins (ANGPTLs), glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPIHBP1), lipase maturation factor 1 (LMF1) and Sel-1 suppressor of Lin-12-like 1 (SEL1L), have completely transformed our understanding of LPL biology.

Angiopoietin-Like Protein 8/Leptin Crosstalk Influences Cardiac Mass in Youths With Cardiometabolic Risk: The BCAMS Study

OBJECTIVES

The link between excess adiposity and left ventricular hypertrophy is multifaceted with sparse data among youths. Given that adipokines/hepatokines may influence lipid metabolism in myocardium, we aimed to investigate the relation of the novel hepatokine angiopoietin-like protein 8 (ANGPTL8) and other adipokines with cardiac structure in a cohort of youths and explore to what extent these adipokines/hepatokines affect cardiac structure through lipids.

METHODS

A total of 551 participants (aged 15-28 years) from the Beijing Child and Adolescent Metabolic Syndrome Study (BCAMS) cohort underwent echocardiographic measurements plus a blood draw assayed for five adipokines/hepatokines including adiponectin, leptin, retinol binding protein 4, fibroblast growth protein 21 and ANGPTL8.

RESULTS

Both ANGPTL8 (β = -0.68 g/m^2.7 per z-score, P= 0.015) and leptin (β = -1.04 g/m^2.7 per z-score, P= 0.036) were significantly inversely associated with left ventricular mass index (LVMI) independent of classical risk factors. Total cholesterol and low-density lipoprotein cholesterol significantly mediated the ANGPTL8-LVMI association (proportion: 19.0% and 17.1%, respectively), while the mediation effect of triglyceride on the ANGPTL8-LVMI relationship was strongly moderated by leptin levels, significantly accounting for 20% of the total effect among participants with higher leptin levels. Other adipokines/hepatokines showed no significant association with LVMI after adjustment for body mass index.

CONCLUSIONS

Our findings suggest ANGPTL8, particularly interacting with leptin, might have a protective role in cardiac remodeling among youths with risk for metabolic syndrome. Our results offer insights into the pathogenesis of the cardiomyopathy and the potential importance of tissue-tissue crosstalk in these effects.

Increased Circulating Angiopoietin-Like Protein 8 Levels Are Associated with Thoracic Aortic Dissection and Higher Inflammatory Conditions

Purpose

Thoracic aortic dissection (TAD) is characterized by an inflammatory response. Angiopoietin-like protein 8 (ANGPTL8) is a hormone involved in the regulation of lipid metabolism and inflammation. However, the relationship between ANGPTL8 and TAD remains unknown.

Methods

This case-control study included 78 TAD patients and 72 controls. The aortic diameter was evaluated by computed tomography and used to assess TAD severity. Circulating ANGPTL8 levels were measured by enzyme-linked immunosorbent assay. Associations of ANGPTL8 with TAD were determined by multivariate logistic regression.

Results

Serum ANGPTL8 levels were significantly higher in TAD patients compared with controls (562.50 ± 20.84 vs. 419.70 ± 22.65 pg/mL, respectively; P < 0.001). After adjusting for confounding factors, circulating ANGPTL8 levels were an independent risk factor for TAD (odds ratio = 1.587/100 pg ANGPTL8, 95% confidence interval [CI] = 1.121–2.247, P < 0.001) and positively associated with diameter (β = 1.081/100 pg ANGPTL8, 95% CI = 0.075–2.086, P = 0.035) and high-sensitivity C-reactive protein (hs-CRP) (β = 0.845/100 pg ANGPTL8, 95% CI = 0.020–1.480, P = 0.009). The area under the curve (AUC) on receiver operating characteristic (ROC) analysis of the combination of ANGPTL8, hs-CRP, and D-dimer was 0.927, and the specificity and sensitivity were 98.46% and 79.49%, respectively. ANGPTL8 was significantly increased in TAD tissue compared with controls. In vitro, ANGPTL8 was increased in angiotensin II (AngII)-treated macrophages and vascular smooth muscle cells (VSMCs), while ANGPTL8 siRNA-mediated knockdown decreased inflammatory factors in AngII-treated macrophages and decreased apoptosis in AngII-treated VSMCs.

Conclusion

ANGPTL8 is associated with TAD occurrence and development, which may involve pro-inflammatory effects on macrophages. ANGPTL8 combined with D-dimer and hs-CRP might be a useful clinical predictor of TAD.

Trial Registration

ChiCTR-COC-17010792 http://www.chictr.org.cn/showproj.aspx?proj=18288

Electronic supplementary material

The online version of this article (10.1007/s10557-019-06924-7) contains supplementary material, which is available to authorized users.

Changes in serum levels of angiopoietin-like protein-8 and glycosylphosphatidylinositol-anchored high-density lipoprotein binding protein 1 after ezetimibe therapy in patients with dyslipidemia

Changes in serum levels of angiopoietin-like protein-8 (ANGPTL8) and glycosylphosphatidylinositol-anchored high-density lipoprotein binding protein 1 (GPIHBP1) in patients with dyslipidemia after ezetimibe therapy remain to be elucidated. Thirty-eight patients who initially received ezetimibe and were followed for 16 weeks were enrolled. Various parameters were investigated before and after 16 weeks of ezetimibe treatment in all patients. In addition, the patients were also divided into metabolic syndrome (MetS) (n = 22) and Non-MetS (n = 16) groups, and various parameters were compared between these groups. ANGPTL8 was significantly positively correlated with triglyceride (TG) and negatively correlated with high-density lipoprotein cholesterol (HDL-C) before treatment in all patients and in the MetS group. After treatment, TC and LDL-C were significantly decreased in all patients, and in both the MetS and Non-MetS groups, whereas there were no changes in TG or HDL-C. Serum levels of remnant-like particle cholesterol (RLP-C) significantly decreased in all patients and in the MetS group. The ANGPTL8 level before treatment was significantly positively associated with TG and negatively correlated with HDL-C in all patients and in the MetS group. ANGPTL8 and GPIHBP1were significantly decreased after treatment in all patients. GPIHBP1 was also significantly decreased after treatment in both groups. In conclusion, this is the first report to support the possibility of a new effect of ezetimibe therapy. Ezetimibe significantly decreased the serum level of LDL-C, but not TG or HDL-C, while reducing ANGPTL8 and GPIHBP1 in all patients with dyslipidemia. In addition, ezetimibe significantly decreased RLP-C levels in the MetS group.

Targeting Angiopoietin in Retinal Vascular Diseases: A Literature Review and Summary of Clinical Trials Involving Faricimab

This review summarizes the latest findings in the literature of Angiopoietin-2 (Ang-2), Tyrosine-protein kinase receptor (Tie-2) complex, and faricimab along with their involvement for the treatment of retinal vascular diseases in various clinical trials. In ischemic diseases, such as diabetic retinopathy, Ang-2 is upregulated, deactivating Tie-2, resulting in vascular leakage, pericyte loss, and inflammation. Recombinant Angiopeotin-1 (Ang-1), Ang-2-blocking molecules, and inhibitors of vascular endothelial protein tyrosine phosphatase (VE-PTP) decrease inflammation-associated vascular leakage, showing therapeutic effects in diabetes, atherosclerosis, and ocular neovascular diseases. In addition, novel studies show that angiopoietin-like proteins may play an important role in cellular metabolism leading to retinal vascular diseases. Current therapeutic focus combines Ang-Tie targeted drugs with other anti-angiogenic or immune therapies. Clinical studies have identified faricimab, a novel bispecific antibody designed for intravitreal use, to simultaneously bind and neutralize Ang-2 and VEGF-A for treatment of diabetic eye disease. By targeting both Ang-2 and vascular endothelial growth factor-A (VEGF-A), faricimab displays an improved and sustained efficacy over longer treatment intervals, delivering superior vision outcomes for patients with diabetic macular edema and reducing the treatment burden for patients with neovascular age-related macular degeneration and diabetic macular edema. Phase 2 results have produced promising outcomes with regard to efficacy and durability. Faricimab is currently being evaluated in global Phase 3 studies.

Angiopoietin-like protein 8 differentially regulates ANGPTL3 and ANGPTL4 during postprandial partitioning of fatty acids

Angiopoietin-like protein (ANGPTL)8 has been implicated in metabolic syndrome and reported to regulate adipose FA uptake through unknown mechanisms. Here, we studied how complex formation of ANGPTL8 with ANGPTL3 or ANGPTL4 varies with feeding to regulate LPL. In human serum, ANGPTL3/8 and ANGPTL4/8 complexes both increased postprandially, correlated negatively with HDL, and correlated positively with all other metabolic syndrome markers. ANGPTL3/8 also correlated positively with LDL-C and blocked LPL-facilitated hepatocyte VLDL-C uptake. LPL-inhibitory activity of ANGPTL3/8 was >100-fold more potent than that of ANGPTL3, and LPL-inhibitory activity of ANGPTL4/8 was >100-fold less potent than that of ANGPTL4. Quantitative analyses of inhibitory activities and competition experiments among the complexes suggested a model in which localized ANGPTL4/8 blocks the LPL-inhibitory activity of both circulating ANGPTL3/8 and localized ANGPTL4, allowing lipid sequestration into fat rather than muscle during the fed state. Supporting this model, insulin increased ANGPTL3/8 secretion from hepatocytes and ANGPTL4/8 secretion from adipocytes. These results suggest that low ANGPTL8 levels during fasting enable ANGPTL4-mediated LPL inhibition in fat tissue to minimize adipose FA uptake. During feeding, increased ANGPTL8 increases ANGPTL3 inhibition of LPL in muscle via circulating ANGPTL3/8, while decreasing ANGPTL4 inhibition of LPL in adipose tissue through localized ANGPTL4/8, thereby increasing FA uptake into adipose tissue. Excessive caloric intake may shift this system toward the latter conditions, possibly predisposing to metabolic syndrome.

Proprotein Convertase Subtilisin/Kexin Type 9, Angiopoietin-Like Protein 8, Sortilin, and Cholesteryl Ester Transfer Protein-Friends of Foes for Psoriatic Patients at the Risk of Developing Cardiometabolic Syndrome?

Psoriasis is a systemic, immune-metabolic disease with strong genetic predispositions and autoimmune pathogenic traits. During psoriasis progression, a wide spectrum of comorbidities comes into play with the leading role of the cardio-metabolic syndrome (CMS) that occurs with the frequency of 30–50% amongst the psoriatic patients. Both conditions—psoriasis and CMS—have numerous common pathways, mainly related to proinflammatory pathways and cytokine profiles. Surprisingly, despite the years of research, the exact pathways linking the occurrence of CMS in the psoriasis population are still not fully understood. Recently published papers, both clinical and based on the basic science, shed new light into this relationship providing an insight into novel key-players proteins with plausible effects on above-mentioned interplay. Taking into account recent advances in this important medical matter, this review aims to discuss comprehensively the role of four proteins: proprotein convertase subtilisin/kexin type-9 (PSCK9), angiopoietin-like protein 8 (ANGPLT8), sortilin (SORT1), and cholesteryl ester transfer proteins (CEPT) as plausible links between psoriasis and CMS.

The Impact of Psoriasis and Metabolic Syndrome on the Systemic Inflammation and Oxidative Damage to Nucleic Acids

BACKGROUND

Psoriasis is a chronic systemic inflammatory disease associated with a wide range of comorbidities, including metabolic syndrome (MetS). Serum calprotectin, ANGPTL8, and oxidative damage to nucleic acids might be associated with both diseases. The presented study describes the influence of psoriasis and MetS on the serum levels of markers of systemic inflammation (calprotectin and ANGPTL8) and markers of oxidative damage to nucleic acids. The applicability of serum levels of calprotectin and ANGPTL8 for monitoring of the activity of psoriasis (diagnostic markers) is also evaluated.

METHODS

Clinical examination (PASI score, MetS), enzyme-linked immunosorbent assay (ELISA), and Enzyme Immunoassay (EIA). Serum calprotectin, ANGPTL8, 8-hydroxy-2'-deoxyguanosine, 8-hydroxyguanosine, and 8-hydroxyguanine. Results and Conclusions. The psoriasis significantly increased the serum level of calprotectin and the serum level of oxidative damage to nucleic acids, however not the serum level of ANGPTL8. The presence of MetS did not significantly affect the serum levels of calprotectin, ANGPTL8, and oxidative damage to nucleic acids in either psoriasis patients or controls. It seems that the serum level of calprotectin (but not the serum level of ANGPTL8) could be used as a biomarker for monitoring the activity of psoriasis.

Molecular mechanism of the effect of angiopoietin-like protein 8 on the proliferation, invasion and migration of placental trophoblasts in preeclampsia

Preeclampsia (PE) is a pregnancy-specific systemic disorder characterized by various manifestations of organ dysfunction. Inadequate trophoblastic invasion of the uterine wall is involved in the pathogenesis of PE. Angiopoietin-like protein 8 (ANGPTL8) serves an important role in cardiovascular disease development and may have a potential effect on cell proliferation. In the present study, downregulation of ANGPTL8 promoted cell proliferation, decreased p21 expression, and increased the expression levels of cyclin-dependent kinase 2 and proliferating cell nuclear antigen in HTR8/SVneo cells. Silencing of ANGPTL8 led to significant acceleration in cell migration and invasion, and markedly enhanced the matrix metalloproteinase (MMP)-2 and MMP-9 expression levels. In addition, the protein expression levels of tissue inhibitor of matrix metalloproteinase (TIMP)-1 and TIMP-2 were decreased in the group transfected with small interfering RNA (si)-ANGPTL8-1 as compared with those in the control and si-negative control groups. Taken together, these results indicated that ANGPTL8 downregulation promoted the proliferation, migration and invasion of trophoblast cells. Thus, ANGPTL8 suppresses the viability, proliferation, migration and invasion of trophoblast cells, and may be a potential therapeutic target for the clinical treatment of PE.

Evidences for Expression and Location of ANGPTL8 in Human Adipose Tissue

The metabolism of triglycerides (TGs) is regulated, among others, by the lipoprotein lipase (LPL) that hydrolyses the TGs on endothelial cells. In turn, LPL is inhibited by the ANGPTLs family of proteins, such as ANGPTL3, 4, and, 8; the latter is the least known. In this work, we have tried to establish the expression and localisation of the Angiopoietin-like 8 (ANGPTL8) protein in the visceral adipose tissue (VAT) of morbid-obese and non-obese patients. 109 subjects (66 women and 43 men) undergoing laparoscopic surgery participated in this study. A blood sample and a portion of the VAT were obtained, and the patients were classified according to their Body Mass Index (BMI) as non-obese (19.5–30 kg/m²) and morbid-obese (40–50 kg/m²). No significant changes in ANGPTL8 plasma levels were determined by EIA in obese patients. The immunocytochemistry and Western blotting showed the presence of increased ANGPTL8 in morbid-obese patients (p < 0.05). In-situ hybridisation and a real time polymerase chain reaction (RT-PCR) confirmed that the mRNA that encodes ANGPTL8 was present in adipocytes, without differences in their nutritional state (p = 0.89), and even in the endothelial cells. Our data suggests that ANGPT8 plasmatic levels do not change significantly in patients with morbid obesity, although there is a modest difference related to gender. Besides, we demonstrate that in visceral adipose tissue, ANGPTL8 is well defined in the cytoplasm of adipocytes coexisting with perilipin-1 and its mRNA, also is present in endothelial cells. These findings suggest the possibility that among other functions, ANGPTL8 could perform either a paracrine and/or an endocrine role in the adipose tissue.

Causes and Consequences of Hypertriglyceridemia

Elevations in plasma triglyceride are the result of overproduction and impaired clearance of triglyceride-rich lipoproteins-very low-density lipoproteins (VLDL) and chylomicrons. Hypertriglyceridemia is characterized by an accumulation in the circulation of large VLDL-VLDL₁-and its lipolytic products, and throughout the VLDL-LDL delipidation cascade perturbations occur that give rise to increased concentrations of remnant lipoproteins and small, dense low-density lipoprotein (LDL). The elevated risk of atherosclerotic cardiovascular disease in hypertriglyceridemia is believed to result from the exposure of the artery wall to these aberrant lipoprotein species. Key regulators of the metabolism of triglyceride-rich lipoproteins have been identified and a number of these are targets for pharmacological intervention. However, a clear picture is yet to emerge as to how to relate triglyceride lowering to reduced risk of atherosclerosis.

The potential role of angiopoietin-like protein-8 in type 2 diabetes mellitus: a possibility for predictive diagnosis and targeted preventive measures?

Background

Previous studies showed altered angiopoietin-like protein-8 (ANGPTL-8) circulating levels in type 2 diabetes mellitus (DM). Whether or not the alteration in ANGPTL-8 level can be a predictive maker for increased DM risk remains unclear.

Aim

Investigating possible role of ANGPTL-8 as a risk predictor of type2 DM, in addition to a set of factors likely to affect ANGPTL-8 level.

Methods

One hundred recently diagnosed persons with type 2 DM and 100 sex- and age-matched healthy controls were enrolled. Exclusion criteria included type 1 DM, acute infections, history of chronic kidney disease, malignancy, and blood loss or transfusion. Serum levels of ANGPTL-8, blood pressure, weight, height, glycosylated hemoglobin (HbA1c), fasting blood glucose, cystatin C, lipid profile, liver, and kidney function tests were assessed. The independent relationship between DM and ANGPTL-8 was tested in the unadjusted and multiple-adjusted regression models.

Results

Serum ANGPTL-8 levels showed significant elevation among persons with vs. without DM (p = 0.006), positive correlation with HbA1c (p < 0.001), and negative correlation with estimated GFR (eGFR) (p = 0.003) but no significant correlation to fasting glucose level. In the unadjusted model, patients in the third tertile of ANGPTL-8 had 4 times risk of DM (OR 4.03; 95% CI = 1.37-11.84). Data adjustment for cardiovascular diseases, smoking, body mass index, systolic blood pressure, alanine transaminase (ALT), and low-density lipoprotein (LDL) increased the direct relationship between ANGPTL-8 and DM (OR 6.26; 95% CI = 1.21-32.50). However, the risk significantly decreased after adjustment of Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) eGFR creatinine-cystatin (OR 2.17; 95% CI = 0.10-49.84).

Conclusion

This study highlights a possible predictive role of ANGPTL-8 in diabetic complications, particularly nephropathy. Larger prognostic studies are needed to validate the cause-effect relationship between ANGPTL-8 and deteriorated kidney functions.

Angptl8 mediates food-driven resetting of hepatic circadian clock in mice

Diurnal light-dark cycle resets the master clock, while timed food intake is another potent synchronizer of peripheral clocks in mammals. As the largest metabolic organ, the liver sensitively responds to the food signals and secretes hepatokines, leading to the robust regulation of metabolic and clock processes. However, it remains unknown which hepatokine mediates the food-driven resetting of the liver clock independent of the master clock. Here, we identify Angptl8 as a hepatokine that resets diurnal rhythms of hepatic clock and metabolic genes in mice. Mechanistically, the resetting function of Angptl8 is dependent on the signal relay of the membrane receptor PirB, phosphorylation of kinases and transcriptional factors, and consequently transient activation of the central clock gene Per1. Importantly, inhibition of Angptl8 signaling partially blocks food-entrained resetting of liver clock in mice. We have thus identified Angptl8 as a key regulator of the liver clock in response to food.