Cardiorenal outcomes by indices of liver steatosis and fibrosis in individuals with type 2 diabetes and atherosclerotic cardiovascular disease: Analyses from VERTIS CV,a randomized trial of the sodium-glucose cotransporter-2 inhibitor ertugliflozin

Aim

To conduct a post hoc analysis to explore indices of hepatic steatosis/fibrosis and cardiorenal outcomes in the VERTIS CV study.

Materials and Methods

Patients with type 2 diabetes and atherosclerotic cardiovascular (CV) disease were randomized to ertugliflozin or placebo. Liver steatosis and fibrosis were assessed post hoc using the hepatic steatosis index (HSI) and fibrosis-4 (FIB-4) index to explore associations with cardiorenal outcomes (ertugliflozin and placebo data pooled, intention-to-treat analysis set). Cardiorenal outcomes (major adverse CV events [MACE]; hospitalization for heart failure [HHF]/CV death; CV death; HHF; and a composite kidney outcome) were stratified by baseline HSI and FIB-4 quartiles (Q1-Q4). Change in liver indices and enzymes over time were assessed (for ertugliflozin vs. placebo).

Results

Amongst 8246 participants, the mean age was 64.4 years, body mass index 32.0 kg/m², HSI 44.0 and FIB-4 score 1.34. The hazard ratios (HRs) for MACE, HHF/CV death, CV death, and HHF by FIB-4 score quartile (Q4 vs. Q1) were 1.48 (95% confidence interval [CI] 1.25, 1.76), 2.0 (95% CI 1.63, 2.51), 1.85 (95% CI 1.45, 2.36), and 2.94 (95% CI 1.98, 4.37), respectively (P < 0.0001 for all). With HSI, the incidence of HHF was higher in Q4 versus Q1 (HR 1.52 [95% CI 1.07, 2.17]; P < 0.05). The kidney composite outcome did not differ across FIB-4 or HSI quartiles. Liver enzymes and HSI decreased over time with ertugliflozin.

Conclusion

In VERTIS CV, higher FIB-4 score was associated with CV events. HSI correlated with HHF. Neither measure was associated with the composite kidney outcome. Ertugliflozin was associated with a reduction in liver enzymes and HSI.     

Long-term hepatic safety of lomitapide in homozygous familial hypercholesterolaemia

Introduction

Lomitapide is a microsomal triglyceride transfer protein inhibitor for patients with homozygous familial hypercholesterolaemia. Due to its mechanism of action, potential hepatic effects of lomitapide are of clinical interest. This study aimed to determine the long-term hepatic safety of lomitapide.

Methods

Data were aggregated from the pivotal phase 3 and extension phase clinical trial with lomitapide (median 5.1 years; serum total bilirubin, transaminases, cytokeratin-18 [CK-18] and enhanced liver fibrosis [ELF] score, fat-soluble vitamins and essential fatty acids), 8-year data from the Lomitapide Observational Worldwide Evaluation Registry (LOWER) and real-world evidence from a cohort of patients treated with lomitapide in Italy (hepatic elastography, and FIB-4 score for hepatic fibrosis).

Results

In the phase 3 trial and the LOWER registry, any asymptomatic excursions in liver transaminase levels were not associated with elevations in bilirubin, and no Hy's law cases were detected in up to 8 years follow-up. There were no clinically relevant increases among hepatic biomarkers CK-18, CK-18 fragments or ELF score and fat-soluble vitamins and essential fatty acids remained above normal levels. In 34 patients treated in Italy with lomita pide for more than 9 years, elevations in hepatic fat were mild-to-moderate; hepatic stiffness remained normal, and the mean FIB-4 score remained below the fibrosis threshold value of 2.67.

Conclusions

These data indicate that the hepatic safety of lomitapide remains favourable with no clinically significant elevations in hepatic biomarkers and hepatic stiffness remained normal for more than 9 years follow-up.

Phase 3 trial

NCT00730236; extension phase: NCT00943306; LOWER: NCT02135705.     

Validation of the association between a branched chain amino acid metabolite profile and extremes of coronary artery disease in patients referred for cardiac catheterization

Objective

To validate independent associations between branched-chain amino acids (BCAA) and other metabolites with coronary artery disease (CAD).

Methods

We conducted mass-spectrometry-based profiling of 63 metabolites in fasting plasma from 1983 sequential patients undergoing cardiac catheterization. Significant CAD was defined as CADindex ≥ 32 (at least one vessel with ≥95% stenosis; N = 995) and no CAD as CADindex ≤ 23 and no previous cardiac events (N = 610). Individuals (N = 378) with CAD severity between these extremes were excluded. Principal components analysis (PCA) reduced large numbers of correlated metabolites into uncorrelated factors. Association between metabolite factors and significant CAD vs. no CAD was tested using logistic regression; and between metabolite factors and severity of CAD was tested using linear regression.

Results

Of twelve PCA-derived metabolite factors, two were associated with CAD in multivariable models: factor 10, composed of BCAA (adjusted odds ratio, OR, 1.20; 95% CI 1.05–1.35, p = 0.005) and factor 7, composed of short-chain acylcarnitines, which include byproducts of BCAA metabolism (adjusted OR 1.30; 95% CI 1.14–1.48, p = 0.001). After adjustment for glycated albumin (marker of insulin resistance [IR]) both factors 7 (p = 0.0001) and 10 (p = 0.004) remained associated with CAD. Severity of CAD as a continuous variable (including patients with non-obstructive disease) was associated with metabolite factors 2, 3, 6, 7, 8 and 9; only factors 7 and 10 were associated in multivariable models.

Conclusions

We validated the independent association of metabolites involved in BCAA metabolism with CAD extremes. These metabolites may be reporting on novel mechanisms of CAD pathogenesis that are independent of IR and diabetes.     

Dissociation between APOC3 variants, hepatic triglyceride content and insulin resistance

Nonalcoholic fatty liver disease (NAFLD) is an escalating health problem that is frequently associated with obesity and insulin resistance. The mechanistic relationship between NAFLD, obesity, and insulin resistance is not well understood. A nonsynonymous variant in patatin-like phospholipase domain containing 3 (rs738409, I148M) has been reproducibly associated with increased hepatic triglyceride content (HTGC) but has not been associated with either the body mass index (BMI) or indices of insulin resistance. Conversely, two sequence variants in apolipoprotein C3 (APOC3) that have been linked to hypertriglyceridemia (rs2854117 C > T and rs2854116 T > C) have recently been reported to be associated with both hepatic fat content and insulin resistance. Here we genotyped two APOC3 variants in 1228 African Americans, 843 European Americans and 426 Hispanics from a multiethnic population based study, the Dallas Heart Study and test for association with HTGC and homeostatic model of insulin resistance (HOMA-IR). We also examined the relationship between these two variants and HOMA-IR in the Atherosclerosis Risk in Communities (ARIC) study. No significant difference in hepatic fat content was found between carriers and noncarriers in the Dallas Heart Study. Neither APOC3 variant was associated with HOMA-IR in the Dallas Heart Study; this lack of association was confirmed in the ARIC study, even after the analysis was restricted to lean (BMI < 25 kg/m(2) ) individuals (n = 4399). CONCLUSION: Our data do not support a causal relationship between these two variants in APOC3 and either HTGC or insulin resistance in middle-aged men and women.     

Identification of serum metabolites associated with obesity and traditional risk factors for metabolic disease in Chinese adults

Background and aims

Obesity is a major worldwide health problem and is often associated with many metabolic diseases. Levels of several serum-specific metabolites may be altered in patients with these metabolic diseases. We aimed to investigate the associations of serum metabolite levels with obesity and traditional risk factors for metabolic disease in Chinese individuals.

Non-invasive prediction of hepatocellular carcinoma development using serum fibrosis marker in chronic hepatitis C patients

Background

The FIB-4 index is a simple formula to predict liver fibrosis. This study aimed to evaluate the utility of the FIB-4 index and associated time-course changes as a predictor of hepatocellular carcinoma (HCC) development.

Methods

A total of 171 chronic hepatitis C patients who underwent paired liver biopsies and 875 patients who underwent a single liver biopsy (validation group) were investigated during mean follow-up periods of 6.4 and 5.9 years, respectively. All patients had received interferon therapy and had not achieved a sustained virological response. Factors associated with HCC development were analyzed in these patients.

Results

HCC developed in 30 patients in the paired biopsy group and 89 patients in the validation group. Univariate analysis demonstrated that the FIB-4 index >3.25 and change in the FIB-4 index per year (ΔFIB-4/year) ≥0.3 were predictive factors for HCC development in both groups. Multivariate analysis in the combined population revealed that these two factors were independent. The hazard ratio (HR) for the FIB-4 index >3.25 was 2.7 (p < 0.001) and ΔFIB-4/year ≥0.3 was 1.8 (p = 0.003). Patients with a FIB-4 index >3.25 and a ΔFIB-4/year ≥0.3 were defined as high risk, and those with a FIB-4 index ≤3.25 and a ΔFIB-4/year <0.3 were defined as low risk. The HR of HCC development in patients at high risk was 7.3 (95 % confidence interval 4.3–12.5, p < 0.001).

Conclusions

It was possible to define a group at high risk of developing HCC by intermittently measuring the FIB-4 index and considering time-course changes in this index.     

Associations of cord blood metabolites with perinatal characteristics,newborn anthropometry,and cord blood hormones in project viva

ContextMetabolomics has emerged as a powerful tool to characterize biomarkers and elucidate physiological processes underlying adverse health outcomes. Little is known of these relationships during gestation and infancy, which are critical period for development of metabolic disease risk.ObjectivesTo identify cord blood metabolite patterns associated with birth size; and to investigate relations of the birth size-associated metabolite patterns, and a branched chain amino acid (BCAA) metabolite pattern with a range of newborn and perinatal characteristics.MethodsUsing untargeted mass-spectrometry, we quantified metabolites in cord blood of 126 mother-child pairs. After excluding 103 xenobiotics, we used principal components analysis (PCA) to consolidate the remaining 606 metabolites into principal components (“factors”). Next, we identified factors associated with gestational age-and sex-standardized birthweight z-score (BW/GA) and examined associations of the BW/GA-associated pattern(s) and the BCAA pattern with cord blood insulin, leptin, adiponectin, insulin-like growth factor (IGF)-1, IGF-2, and IGF binding protein 3 (IGFBP-3) using multivariable linear regression. Finally, we examined associations of maternal/perinatal characteristics with the cord blood metabolite patterns.ResultsMean BW/GA z-score was 0.27 ± 0.98 units. About half of the infants were male (52.4%) and white (57.1%). Of the 6 factors identified from PCA, one was associated with higher BW/GA: Factor 5, which comprised metabolites involved in energy production (malate, succinate, fumarate) and nucleotide turnover (inosine 5-monophosphate, adenosine 5-monophosphate, cytidine 5-monophosphate) pathways. In multivariable analysis, Factor 5 was related to higher cord blood leptin (1.64 [95% CI: 0.42, 2.87] ng/mL) and IGF-1 even after adjusting for IGFBP-3 (3.35 [0.25, 6.44] ng/mL). The BCAA pattern was associated with higher BW/GA (0.20 [0.03, 0.36] z-scores) and IGFBP-3 (106.5 [44.7, 168.2] ng/mL). No maternal characteristics were associated with either metabolite pattern; however, infants born via Cesarean delivery exhibited a higher score for Factor 5, and gestation length was inversely associated with the BCAA pattern.ConclusionsMetabolites in energy production and DNA/RNA turnover pathways in cord blood are associated with larger size at birth, and higher leptin and IGF-1. Similarly, the BCAA pattern was associated with larger birth size and IGFBP-3.     

High FIB-4 index as an independent risk factor of prevalent chronic kidney disease in patients with nonalcoholic fatty liver disease

Background

Growing evidence suggests that non-alcoholic fatty liver disease (NAFLD) is linked to an increased risk for chronic kidney disease (CKD); liver fibrosis with biopsy-proven NAFLD has also been shown to associate with an increased risk of CKD. This study compares the diagnostic performance of simple noninvasive tests in identifying prevalent CKD among individuals with ultrasonography-diagnosed NAFLD.

Methods

A total of 755 with ultrasonography-diagnosed NAFLD were included. Estimated glomerular filtration rate and noninvasive markers for hepatic fibrosis: aspartate transaminase to alanine transaminase ratio (AAR), aspartate transaminase to platelet ratio index (APRI), FIB-4 score, NAFLD fibrosis score (NFS) and BARD score were assessed.

Results

Binary logistic regression to generate a propensity score and receiver operating characteristic curves were developed for each of the noninvasive markers for predicting CKD, and the area under the receiver operating characteristic curve was greatest for FIB-4 score (0.750), followed by NFS (0.710), AAR (0.594), APRI (0.587), and BARD score (0.561). A cut-off value of 1.100 for FIB-4 score gave a sensitivity of 68.85 % and a specificity of 71.07 % for predicting CKD. The positive predictive value and negative predictive value were 37.50 and 90.05 %, respectively. In multiple logistic regression analysis, only FIB-4 score ≧1.100 (OR 2.660, 95 % CI 1.201–5.889; p = .016), older age, higher diastolic blood pressure and higher uric acid were independent predictors of CKD.

Conclusions

High noninvasive fibrosis score is associated with an increased risk of prevalent CKD; the FIB-4 is the better predictor. With a cut-off value of 1.100 for FIB-4, it is useful in excluding the presence of CKD in patients with NAFLD.

     

Magnitude of contrast-enhanced ultrasonography as a noninvasive predictor for hepatic fibrosis: comparison with liver stiffness measurement and serum-based models

Purpose

To elucidate the efficiency of contrast-enhanced ultrasonography alone and in combination with other noninvasive models for grading hepatic fibrosis.

Methods

This prospective study included 74 patients with four grades (F1–F4) of chronic liver disease (17, 20, 18, and 19 patients, respectively). Diagnostic performances of the contrast parameter (time to the maximum intensity ratio between the right portal vein and liver parenchyma from the onset of contrast enhancement in the right portal vein) assessed by ultrasonography, liver stiffness measurement (LSM), FIB-4 test, and type IV collagen 7s were compared with histological findings.

Results

Greatest areas under the receiver operating characteristics curve (Az) with the single model were 0.83 (95 % confidence interval 0.71–0.91) for marked fibrosis (≥F2) by FIB-4 test; 0.85 (0.73–0.92) for advanced fibrosis (≥F3) by LSM, and 0.92 (0.83–0.96) by type IV collagen 7s for cirrhosis (F4). When combined, Az for marked fibrosis was ≥0.82; the best Az value was 0.87 (0.74–0.94) for the combination of contrast parameter with FIB-4. Similarly, the Az for advanced fibrosis was ≥0.82, and the best Az value was 0.89 (0.78–0.94) for the combination of contrast parameter with LSM. The Az for cirrhosis was ≥0.95, and the best Az was 0.99 (0.97–1.00) for the combination of contrast parameter with LSM.

Conclusions

The contrast parameter is a promising predictor for grading hepatic fibrosis when combined with LSM or FIB-4.     

Lipids,Lipoproteins, and Metabolites and Risk of Myocardial Infarction and Stroke

Background

Blood lipids are established risk factors for myocardial infarction (MI), but uncertainty persists about the relevance of lipids, lipoprotein particles, and circulating metabolites for MI and stroke subtypes.

Investigating the role of lipid genes in liver disease using fatty liver models of alcohol and high fat in zebrafish (Danio rerio)

Background

Accumulation of lipid in the liver is the first hallmark of both alcohol-related liver disease (ALD) and non-alcohol-related fatty liver disease (NAFLD). Recent studies indicate that specific mutations in lipid genes confer risk and might influence disease progression to irreversible liver cirrhosis. This study aimed to understand the function/s of lipid risk genes driving disease development in zebrafish genetic models of alcohol-related and non-alcohol-related fatty liver.

Methods

We used zebrafish larvae to investigate the effect of alcohol and high fat to model fatty liver and tested the utility of this model to study lipid risk gene functions. CRISPR/Cas9 gene editing was used to create knockdowns in 5 days post-fertilisation zebrafish larvae for the available orthologs of human cirrhosis risk genes (pnpla3, faf2, tm6sf2). To establish fatty liver models, larvae were exposed to ethanol and a high-fat diet (HFD) consisting of chicken egg yolk. Changes in morphology (imaging), survival, liver injury (biochemical tests, histopathology), gene expression (qPCR) and lipid accumulation (dye-specific live imaging) were analysed across treatment groups to test the functions of these genes.

Results

Exposure of 5-day post-fertilisation (dpf) WT larvae to 2% ethanol or HFD for 48 h developed measurable hepatic steatosis. CRISPR-Cas9 genome editing depleted pnpla3, faf2 and tm6sf2 gene expression in these CRISPR knockdown larvae (crispants). Depletion significantly increased the effects of ethanol and HFD toxicity by increasing hepatic steatosis and hepatic neutrophil recruitment ≥2-fold in all three crispants. Furthermore, ethanol or HFD exposure significantly altered the expression of genes associated with ethanol metabolism (cyp2y3) and lipid metabolism-related gene expression, including atgl (triglyceride hydrolysis), axox1, echs1 (fatty acid β-oxidation), fabp10a (transport), hmgcra (metabolism), notch1 (signalling) and srebp1 (lipid synthesis), in all three pnpla3, faf2 and tm6sf2 crispants. Nile Red staining in all three crispants revealed significantly increased lipid droplet size and triglyceride accumulation in the livers following exposure to ethanol or HFD.

Conclusions

We identified roles for pnpla3, faf2 and tm6sf2 genes in triglyceride accumulation and fatty acid oxidation pathways in a zebrafish larvae model of fatty liver.     

Noninvasive scoring systems in patients with nonalcoholic fatty liver disease with normal alanine aminotransferase levels

Background

The severity of liver fibrosis must be estimated to determine the prognosis, for surveillance, and for optimal treatment of nonalcoholic fatty liver disease (NAFLD). However, the severity of hepatic fibrosis tends to be underestimated in patients with normal ALT.

Methods

We investigated histological data and scoring systems (FIB-4 index, NAFLD fibrosis score, BARD score, and AST/ALT ratio) of 1,102 liver-biopsy-confirmed NAFLD patients.

Results

A total of 235 NAFLD patients with normal ALT were estimated to exist. The ratio of advanced fibrosis (stage 3–4) was seen in 16.1 % of subjects with normal ALT. Scoring systems, especially the FIB-4 index and NAFLD fibrosis score, were clinically very useful (AUROC >0.8), even in patients with normal ALT. Furthermore, with resetting of the cutoff values, the FIB-4 index (>1.659) and NAFLD fibrosis score (>0.735) were found to have a higher sensitivity and higher specificity for the prediction of advanced fibrosis, and all of these scoring systems (FIB-4 index, NAFLD fibrosis score, BARD score, and AST/ALT ratio) had higher negative predictive values (>90.3 %). By using the resetting cutoff value, liver biopsy could have been avoided in 60.4 % (FIB-4), 66.4 % (NAFLD fibrosis score), 51.9 % (BARD score), and 62.1 % (AST/ALT ratio).

Conclusions

We reset the cutoff values of numerous non-invasive scoring systems to improve their clinical usefulness in the prediction of liver fibrosis in NAFLD patients with normal ALT, and these non-invasive scoring systems with the reset cutoff values could be of substantial benefit to reduce the number of liver biopsies performed.     

Genetic evidence of a causal effect of insulin resistance on branched-chain amino acid levels

Aims/hypothesis

Fasting plasma levels of branched-chain amino acids (BCAAs) are associated with insulin resistance, but it remains unclear whether there is a causal relation between the two. We aimed to disentangle the causal relations by performing a Mendelian randomisation study using genetic variants associated with circulating BCAA levels and insulin resistance as instrumental variables.

Methods

We measured circulating BCAA levels in blood plasma by NMR spectroscopy in 1,321 individuals from the ADDITION-PRO cohort. We complemented our analyses by using previously published genome-wide association study (GWAS) results from the Meta-Analyses of Glucose and Insulin-related traits Consortium (MAGIC) (n?=?46,186) and from a GWAS of serum BCAA levels (n?=?24,925). We used a genetic risk score (GRS), calculated using ten established fasting serum insulin associated variants, as an instrumental variable for insulin resistance. A GRS of three variants increasing circulating BCAA levels was used as an instrumental variable for circulating BCAA levels.

Results

Fasting plasma BCAA levels were associated with higher HOMA-IR in ADDITION-PRO (β 0.137 [95% CI 0.08, 0.19] p?=?6?×?10^?7). However, the GRS for circulating BCAA levels was not associated with fasting insulin levels or HOMA-IR in ADDITION-PRO (β ?0.011 [95% CI ?0.053, 0.032] p?=?0.6 and β ?0.011 [95% CI ?0.054, 0.031] p?=?0.6, respectively) or in GWAS results for HOMA-IR from MAGIC (β for valine-increasing GRS ?0.012 [95% CI ?0.069, 0.045] p?=?0.7). By contrast, the insulin-resistance-increasing GRS was significantly associated with increased BCAA levels in ADDITION-PRO (β 0.027 [95% CI 0.005, 0.048] p?=?0.01) and in GWAS results for serum BCAA levels (β 1.22 [95% CI 0.71, 1.73] p?=?4?×?10^?6, β 0.96 [95% CI 0.45, 1.47] p?=?3?×?10^?4, and β 0.67 [95% CI 0.16, 1.18] p?=?0.01 for isoleucine, leucine and valine levels, respectively) and instrumental variable analyses in ADDITION-PRO indicated that HOMA-IR is causally related to higher circulating fasting BCAA levels (β 0.73 [95% CI 0.26, 1.19] p?=?0.002).

Conclusions/interpretation

Our results suggest that higher BCAA levels do not have a causal effect on insulin resistance while increased insulin resistance drives higher circulating fasting BCAA levels.

     

Plasma branched chain/aromatic amino acids,enriched Mediterranean diet and risk of type 2 diabetes: case-cohort study within the PREDIMED Trial

Aims/hypothesis

Branched-chain amino acids (BCAAs) and aromatic amino acids (AAAs) are associated with type 2 diabetes. However, repeated measurements of BCAA/AAA and their interactions with dietary interventions have not been evaluated. We investigated the associations between baseline and changes at 1 year in BCAA/AAA with type 2 diabetes in the context of a Mediterranean diet (MedDiet) trial.

Methods

We included 251 participants with incident type 2 diabetes and a random sample of 694 participants (641 participants without type 2 diabetes and 53 overlapping cases) in a case-cohort study nested within the PREvención con DIeta MEDiterránea (PREDIMED) trial. Participants were randomised to a MedDiet+extra-virgin olive oil (n?=?273), a MedDiet+nuts (n?=?324) or a control diet (n?=?295). We used LC-MS/MS to measure plasma levels of amino acids. Type 2 diabetes was a pre-specified secondary outcome of the PREDIMED trial.

Results

Elevated plasma levels of individual BCAAs/AAAs were associated with higher type 2 diabetes risk after a median follow-up of 3.8 years: multivariable HR for the highest vs lowest quartile ranged from 1.32 for phenylalanine ([95% CI 0.90, 1.92], p for trend?=?0.015) to 3.29 for leucine ([95% CI 2.03, 5.34], p for trend<0.001). Increases in BCAA score at 1 year were associated with higher type 2 diabetes risk in the control group with HR per SD?=?1.61 (95% CI 1.02, 2.54), but not in the MedDiet groups (p for interaction <0.001). The MedDiet+extra-virgin olive oil significantly reduced BCAA levels after 1 year of intervention (p?= 0.005 vs the control group).

Conclusions/interpretation

Our results support that higher baseline BCAAs and their increases at 1 year were associated with higher type 2 diabetes risk. A Mediterranean diet rich in extra-virgin olive oil significantly reduced the levels of BCAA and attenuated the positive association between plasma BCAA levels and type 2 diabetes incidence.Clinical trial number: SRCTN35739639 (www.controlled-trials.com)

     

Combining a nontargeted and targeted metabolomics approach to identify metabolic pathways significantly altered in polycystic ovary syndrome

ObjectivePolycystic ovary syndrome (PCOS) is a condition of androgen excess and chronic anovulation frequently associated with insulin resistance. We combined a nontargeted and targeted metabolomics approach to identify pathways and metabolites that distinguished PCOS from metabolic syndrome (MetS).MethodsTwenty obese women with PCOS were compared with 18 obese women without PCOS. Both groups met criteria for MetS but could not have diabetes mellitus or take medications that treat PCOS or affect lipids or insulin sensitivity. Insulin sensitivity was derived from the frequently sampled intravenous glucose tolerance test. A nontargeted metabolomics approach was performed on fasting plasma samples to identify differentially expressed metabolites, which were further evaluated by principal component and pathway enrichment analysis. Quantitative targeted metabolomics was then applied on candidate metabolites. Measured metabolites were tested for associations with PCOS and clinical variables by logistic and linear regression analyses.ResultsThis multiethnic, obese sample was matched by age (PCOS, 37 ± 6; MetS, 40 ± 6 years) and body mass index (BMI) (PCOS, 34.6 ± 5.1; MetS, 33.7 ± 5.2 kg/m²). Principal component analysis of the nontargeted metabolomics data showed distinct group separation of PCOS from MetS controls. From the subset of 385 differentially expressed metabolites, 22% were identified by accurate mass, resulting in 19 canonical pathways significantly altered in PCOS, including amino acid, lipid, steroid, carbohydrate, and vitamin D metabolism. Targeted metabolomics identified many essential amino acids, including branched-chain amino acids (BCAA) that were elevated in PCOS compared with MetS. PCOS was most associated with BCAA (P = .02), essential amino acids (P = .03), the essential amino acid lysine (P = .02), and the lysine metabolite α-aminoadipic acid (P = .02) in models adjusted for surrogate variables representing technical variation in metabolites. No significant differences between groups were observed in concentrations of free fatty acids or vitamin D metabolites. Evaluation of the relationship of metabolites with clinical characteristics showed 1) negative associations of essential and BCAA with insulin sensitivity and sex hormone-binding globulin and 2) positive associations with homeostasis model of insulin resistance and free testosterone; metabolites were not associated with BMI or percent body fat.ConclusionsPCOS was associated with significant metabolic alterations not attributed exclusively to androgen-related pathways, obesity, or MetS. Concentrations of essential amino acids and BCAA are increased in PCOS, which might result from or contribute to their insulin resistance.     

Associations of maternal BMI and insulin resistance with the maternal metabolome and newborn outcomes

Aims/hypothesis

Maternal obesity increases the risk for large-for-gestational-age birth and excess newborn adiposity, which are associated with adverse long-term metabolic outcomes in offspring, probably due to effects mediated through the intrauterine environment. We aimed to characterise the maternal metabolic milieu associated with maternal BMI and its relationship to newborn birthweight and adiposity.

Methods

Fasting and 1 h serum samples were collected from 400 European-ancestry mothers in the Hyperglycaemia and Adverse Pregnancy Outcome Study who underwent an OGTT at ～28 weeks gestation and whose offspring had anthropometric measurements at birth. Metabolomics assays were performed using biochemical analyses of conventional clinical metabolites, targeted MS-based measurement of amino acids and acylcarnitines and non-targeted GC/MS.

Results

Per-metabolite analyses demonstrated broad associations with maternal BMI at fasting and 1 h for lipids, amino acids and their metabolites together with carbohydrates and organic acids. Similar metabolite classes were associated with insulin resistance with unique associations including branched-chain amino acids. Pathway analyses indicated overlapping and unique associations with maternal BMI and insulin resistance. Network analyses demonstrated collective associations of maternal metabolite subnetworks with maternal BMI and newborn size and adiposity, including communities of acylcarnitines, lipids and related metabolites, and carbohydrates and organic acids. Random forest analyses demonstrated contribution of lipids and lipid-related metabolites to the association of maternal BMI with newborn outcomes.

Conclusions/interpretation

Higher maternal BMI and insulin resistance are associated with broad-based changes in maternal metabolites, with lipids and lipid-related metabolites accounting, in part, for the association of maternal BMI with newborn size at birth.

     

Effects of home‐based exercise and branched‐chain amino acid supplementation on aerobic capacity and glycemic control in patients with cirrhosis

Aim

The aim of the current study is to examine whether home‐based step exercise at anaerobic threshold (AT) and branched‐chain amino acid (BCAA) supplementation improve aerobic capacity, ectopic fat in liver and muscle, and glycemic control in patients with liver cirrhosis.

Methods

Six female patients with compensated liver cirrhosis received oral BCAA and were instructed to undertake bench step exercises at an intensity that corresponded to AT, with a goal of performing 140 min of exercise per week at home for 12 months. Fat deposition in liver (liver to spleen ratio) and intramuscular adipose tissue content were assessed at baseline and after 6 and 12 months by computed tomography. Glycemic control indices (homeostasis model assessment of insulin resistance, hemoglobin A_1c [HbA_1c], glycated albumin [GA] and chronic liver disease [CLD]‐HbA_1c [average of HbA_1c and GA/3]) were also measured.

Results

Twelve months of moderate training significantly increased AT, which is an index of aerobic capacity, but no changes were observed in body weight, liver to spleen ratio, or intramuscular adipose tissue content. Glycated albumin significantly decreased (P < 0.05) and there tended to be a similar decrease in CLD‐HbA_1c (P < 0.1) after the exercise. The baseline serum triglyceride level correlated with changes in GA (P < 0.01) and CLD‐HbA_1c (P < 0.1).

Conclusion

The current results suggest that the combination of home‐based step exercise at AT and BCAA supplementation enhances aerobic capacity and potentially improves glycemic control in patients with cirrhosis without changes in body weight. The baseline serum serum triglyceride may partially explain the degree of improvement in glycemic control with exercise and BCAA intervention.

     

Predictive value of FIB-4 and APRI versus METAVIR on sustained virologic response in genotype 1 hepatitis C patients

Purpose

Advanced liver fibrosis is a negative predictor of virologic response in genotype 1 chronic hepatitis C (CHC) patients. Biopsy, however, is invasive, costly, and carries some risk of complications.

Methods

Using data from the prospective, international cohort study PROPHESYS, we assessed two alternative noninvasive measures of fibrosis, the FIB-4 and AST-to-platelet ratio index (APRI), to predict virologic response in CHC patients.

Results

CHC genotype 1, monoinfected, treatment-naive patients prescribed peginterferon alfa-2a (40 KD)/ribavirin in accordance with country-specific legal and regulatory requirements and who had baseline METAVIR, FIB-4, and APRI scores (N = 1,592) were included in this analysis. Patients were stratified according to the baseline METAVIR, FIB-4, or APRI score to assess virologic response [hepatitis C virus (HCV) RNA <50 IU/mL] by week 4 of treatment (rapid virologic response) and 24 weeks after untreated follow-up ]sustained virologic response (SVR)]. Baseline predictors of SVR were explored by multiple logistic regression, and the strength of the association between each fibrosis measure and SVR was evaluated. Both FIB-4 and APRI scores increased with increasing levels of biopsy-assessed fibrosis. The association between FIB-4 and SVR (p < 0.1 × 10^?30) was stronger than that between METAVIR (p = 3.86 × 10^?13) or APRI (p = 5.48 × 10^?6) and SVR. Baseline factors significantly associated with SVR included male gender, lower HCV RNA, lower FIB-4 score, no steatosis, and higher alanine aminotransferase ratio.

Conclusion

The FIB-4 index provides a valuable, noninvasive measure of fibrosis and can be used to predict virologic response in patients treated with peginterferon alfa-2a (40  KD)/ribavirin.     

An Overview of Metabolic Phenotyping in Blood Pressure Research

Purpose of the Review

This review presents the analytical techniques, processing and analytical steps used in metabolomics phenotyping studies, as well as the main results from epidemiological studies on the associations between metabolites and high blood pressure.

Recent Findings

A variety of metabolomic approaches have been applied to a range of epidemiological studies to uncover the pathophysiology of high blood pressure. Several pathways have been suggested in relation to blood pressure including the possible role of the gut microflora, inflammatory, oxidative stress, and lipid pathways. Metabolic changes have also been identified associated with blood pressure lowering effects of diets high in fruits and vegetables and low in meat intake. However, the current body of literature on metabolic profiling and blood pressure is still in its infancy, not fully consistent and requires careful interpretation.

Summary

Metabolic phenotyping is a promising approach to uncover metabolic pathways associated with high blood pressure and throw light into the complex pathophysiology of hypertension.