Evidence of a causal and modifiable relationship between kidney function and circulating trimethylamine N-oxide.

The host-microbiota co-metabolite trimethylamine N-oxide (TMAO) is linked to increased cardiovascular risk but how its circulating levels are regulated remains unclear. We applied "explainable" machine learning, univariate, multivariate and mediation analyses of fasting plasma TMAO concentration and a multitude of phenotypes in 1,741 adult Europeans of the MetaCardis study. Here we show that next to age, kidney function is the primary variable predicting circulating TMAO, with microbiota composition and diet playing minor, albeit significant, roles. Mediation analysis suggests a causal relationship between TMAO and kidney function that we corroborate in preclinical models where TMAO exposure increases kidney scarring. Consistent with our findings, patients receiving glucose-lowering drugs with reno-protective properties have significantly lower circulating TMAO when compared to propensity-score matched control individuals. Our analyses uncover a bidirectional relationship between kidney function and TMAO that can potentially be modified by reno-protective anti-diabetic drugs and suggest a clinically actionable intervention for decreasing TMAO-associated excess cardiovascular risk.

Exploring the endocrine heart: an in-depth interview with Jens Peter Gøtze.

Rosanna Zolna, Commissioning Editor for Biomarkers in Medicine, speaks to Jens Peter Gøtze.

Microbiome and metabolome features of the cardiometabolic disease spectrum.

Previous microbiome and metabolome analyses exploring non-communicable diseases have paid scant attention to major confounders of study outcomes, such as common, pre-morbid and co-morbid conditions, or polypharmacy. Here, in the context of ischemic heart disease (IHD), we used a study design that recapitulates disease initiation, escalation and response to treatment over time, mirroring a longitudinal study that would otherwise be difficult to perform given the protracted nature of IHD pathogenesis. We recruited 1,241 middle-aged Europeans, including healthy individuals, individuals with dysmetabolic morbidities (obesity and type 2 diabetes) but lacking overt IHD diagnosis and individuals with IHD at three distinct clinical stages-acute coronary syndrome, chronic IHD and IHD with heart failure-and characterized their phenome, gut metagenome and serum and urine metabolome. We found that about 75% of microbiome and metabolome features that distinguish individuals with IHD from healthy individuals after adjustment for effects of medication and lifestyle are present in individuals exhibiting dysmetabolism, suggesting that major alterations of the gut microbiome and metabolome might begin long before clinical onset of IHD. We further categorized microbiome and metabolome signatures related to prodromal dysmetabolism, specific to IHD in general or to each of its three subtypes or related to escalation or de-escalation of IHD. Discriminant analysis based on specific IHD microbiome and metabolome features could better differentiate individuals with IHD from healthy individuals or metabolically matched individuals as compared to the conventional risk markers, pointing to a pathophysiological relevance of these features.

Impairment of gut microbial biotin metabolism and host biotin status in severe obesity: effect of biotin and prebiotic supplementation on improved metabolism.

OBJECTIVES: Gut microbiota is a key component in obesity and type 2 diabetes, yet mechanisms and metabolites central to this interaction remain unclear. We examined the human gut microbiome's functional composition in healthy metabolic state and the most severe states of obesity and type 2 diabetes within the MetaCardis cohort. We focused on the role of B vitamins and B7/B8 biotin for regulation of host metabolic state, as these vitamins influence both microbial function and host metabolism and inflammation. DESIGN: We performed metagenomic analyses in 1545 subjects from the MetaCardis cohorts and different murine experiments, including germ-free and antibiotic treated animals, faecal microbiota transfer, bariatric surgery and supplementation with biotin and prebiotics in mice. RESULTS: Severe obesity is associated with an absolute deficiency in bacterial biotin producers and transporters, whose abundances correlate with host metabolic and inflammatory phenotypes. We found suboptimal circulating biotin levels in severe obesity and altered expression of biotin-associated genes in human adipose tissue. In mice, the absence or depletion of gut microbiota by antibiotics confirmed the microbial contribution to host biotin levels. Bariatric surgery, which improves metabolism and inflammation, associates with increased bacterial biotin producers and improved host systemic biotin in humans and mice. Finally, supplementing high-fat diet-fed mice with fructo-oligosaccharides and biotin improves not only the microbiome diversity, but also the potential of bacterial production of biotin and B vitamins, while limiting weight gain and glycaemic deterioration. CONCLUSION: Strategies combining biotin and prebiotic supplementation could help prevent the deterioration of metabolic states in severe obesity. TRIAL REGISTRATION NUMBER: NCT02059538.

Combinatorial, additive and dose-dependent drug-microbiome associations.

During the transition from a healthy state to cardiometabolic disease, patients become heavily medicated, which leads to an increasingly aberrant gut microbiome and serum metabolome, and complicates biomarker discovery1-5. Here, through integrated multi-omics analyses of 2,173 European residents from the MetaCardis cohort, we show that the explanatory power of drugs for the variability in both host and gut microbiome features exceeds that of disease. We quantify inferred effects of single medications, their combinations as well as additive effects, and show that the latter shift the metabolome and microbiome towards a healthier state, exemplified in synergistic reduction in serum atherogenic lipoproteins by statins combined with aspirin, or enrichment of intestinal Roseburia by diuretic agents combined with beta-blockers. Several antibiotics exhibit a quantitative relationship between the number of courses prescribed and progression towards a microbiome state that is associated with the severity of cardiometabolic disease. We also report a relationship between cardiometabolic drug dosage, improvement in clinical markers and microbiome composition, supporting direct drug effects. Taken together, our computational framework and resulting resources enable the disentanglement of the effects of drugs and disease on host and microbiome features in multimedicated individuals. Furthermore, the robust signatures identified using our framework provide new hypotheses for drug-host-microbiome interactions in cardiometabolic disease.

Commentary on: Peptidylglycine α-amidating Monooxygenase is Required for Atrial Secretory Granule Formation.

The electron-dense spherical granules found in the perinuclear region of atrial myocytes store and release both proatrial and probrain natriuretic peptides (proANP and proBNP, respectively). Mature ANP and BNP produce vasodilation and natriuresis and inhibit the renin-angiotensin and sympathetic nervous systems. Although neither ANP nor BNP is a-amidated, Peptidylglycine a-Amidating Monooxygenase (PAM), an integral membrane enzyme known to catalyze the a-amidation of peptidylglycine precursors, is the major atrial granule membrane protein. Selective deletion of PAM from cardiomyocytes impairs their ability to store proANP, resulting in an increase in proANP secretion. Exogenous expression of active or inactive PAM protein restores the ability of atrial myocytes to store proANP, leading to the suggestion that PAM functions as a cargo receptor for newly synthesized proANP.

Plasma Somatostatin in Advanced Heart Failure: Association with Cardiac Filling Pressures and Outcome.

BACKGROUND: Somatostatin inhibits intestinal motility and hormonal secretion and is a potent arterial vasoconstrictor of the splanchnic blood flow. It is unknown if somatostatin concentrations are associated with central hemodynamic measurements in patients with advanced heart failure (HF). METHODS: A prospective study of HF patients with a left ventricular ejection fraction (LVEF) <45% referred to right heart catheterization (RHC) for evaluation for heart transplantation (HTX) or left ventricular assist device (LVAD). RESULTS: Fifty-three patients were included with mean LVEF 18 ± 8% and majority in NYHA-class III-IV (79%). Median plasma somatostatin concentration was 18 pmol/L. In univariable regression analysis, log(somatostatin) was associated with increased central venous pressure (CVP; r2 = 0.14, p = 0.003) and a reduced cardiac index (CI; r2 = 0.15, p = 0.004). When adjusted for selected clinical variables (age, gender, LVEF, eGFR and BMI), log(somatostatin) remained a significant predictor of CVP (p = 0.044). Increased somatostatin concentrations predicted mortality in multivariable models (hazard ratio: 5.2 [1.2-22.2], p = 0.026) but not the combined endpoint of death, LVAD implantation or HTX. CONCLUSIONS: Somatostatin concentrations were associated with CVP and CI in patients with HF. The pathophysiological mechanism may be related to congestion and/or hypoperfusion of the intestine. Somatostatin was an independent predictor of mortality in advanced HF.

Fibrogenesis and inflammation contribute to the pathogenesis of cirrhotic cardiomyopathy.

BACKGROUND: Fibrogenesis and inflammation contribute to the progression of cirrhosis. However, it is unknown if these processes also contribute to the development of cirrhotic cardiomyopathy (CCM). Novel magnetic resonance imaging with quantification of the extracellular volume (ECV) provides an estimate of the fibrotic remodelling in the liver and heart. AIM: To investigate the relationship between liver and cardiac ECV in cirrhosis and their association with collagen turnover and inflammation. METHODS: A prospective study of 52 patients with cirrhosis and 14 healthy controls. All patients underwent contrast-enhanced MRI with T1-mapping and quantification of myocardial and liver ECV, biochemical assessments of collagen turnover (PRO-C3, PRO-C5, PRO-C6, collagen type IV degradation fragment, collagen type V degradation fragment, LG1M) and inflammation (TNFα, IL-1ß, IL-6, IL-8, IL-18, SDF1α, sCD163, sMR, soluble macrophage mannose receptor). RESULTS: Myocardial and liver ECV were increased in patients compared with healthy controls (myocardial ECV 31.2 ± 5.5% vs 27.4 ± 2.9%, P = 0.037; liver ECV 44.1 ± 9.6% vs 33.7 ± 6.7%, P < 0.001). Myocardial ECV correlated strongly with liver ECV (r = 0.48, P = 0.001) and biomarkers of collagen formation and inflammation (P < 0.005). Similarly, liver ECV correlated with biomarkers of collagen formation and inflammation (P < 0.003). In a multivariate analysis, liver ECV was predicted by biomarkers of collagen formation (PRO-C3 and PRO-C6), whereas myocardial ECV was predicted by biomarkers of collagen formation (PRO-C6) and inflammation (IL-6 and sMR). CONCLUSION: Structural myocardial changes seem closely related to liver fibrosis in patients with cirrhosis. The strong associations with biomarkers of collagen formation and inflammation provide new insight into the role of inflammation and fibrogenesis in the development of structural cardiac abnormalities, potentially leading to CCM.

Cardiovascular prognostic value of echocardiography and N terminal pro B-type natriuretic peptide in type 1 diabetes: the Thousand & 1 Study.

AIMS: Patients with type 1 diabetes have a high risk of cardiovascular disease. Yet, the importance of routine assessment of myocardial function in patients with type 1 diabetes is not known. Thus, we examined the prognostic importance of NT-proBNP and E/e', an echocardiographic measure of diastolic function, in type 1 diabetes patients with preserved left ventricular ejection fraction (LVEF) and without known heart disease. METHODS AND RESULTS: Type 1 diabetes patients without known heart disease and LVEF ≥45% enrolled in the Thousand and 1 study were included and followed through nationwide registries. The risk of major cardiovascular events (MACE) and death associated with levels of NT-proBNP and E/e' was examined. Of 960 patients, median follow-up of 6.3 years (Q1-Q3: 5.7-7.0), 121 (12%) experienced MACE and 51 (5%) died. Increased levels of both NT-proBNP and E/e' were associated with worse outcomes (adjusted hazard ratios for MACE = 1.56 (1.23-1.98) and 4.29 (2.25-8.16) per Loge increase for NT-proBNP and E/e', respectively). NT-proBNP and E/e' combined significantly improved the discrimination power of the Steno T1D risk engine (MACE, C-index: 0.813 (0.779-0.847) vs 0.779 (0.742-0.816); P = 0.0001; All-cause mortality, C-index 0.855 (0.806-0.903) vs 0.828 (0.776-0.880); P = 0.03). CONCLUSION: In patients with type 1 diabetes, preserved ejection fraction, and no known heart disease, NT-proBNP and E/e' were associated with increased risk of MACE and all-cause mortality. The risks associated with NT-proBNP and E/e' combined identified patients at remarkably high risk.

Biomarkers in patients with Takotsubo cardiomyopathy compared to patients with acute anterior ST-elevation myocardial infarction.

Background: Takotsubo cardiomyopathy (TTC) is a syndrome of acute non-coronary heart failure with similar symptoms and electrocardiograms to acute anterior ST-elevation myocardial infarction (STEMI). Little is known about the pathophysiology of TTC. We assessed admission plasma concentrations of biomarkers reflecting neuroendocrine response (copeptin, mid-regional-pro-adrenomedullin, pro-atrial-natriuretic-peptide, soluble thrombomodulin (sTM), syndecan-1) and inflammation (suppression-of-tumorigenicity 2 (ST2), high-sensitive C-reactive-protein) in TTC patients and compared to patients with acute anterior STEMI.Materials and methods: Twenty TTC patients were matched with 40 STEMI patients by age, gender and left ventricular ejection fraction. Blood was sampled upon hospital admission immediately before acute coronary angiography.Results: The groups had similar comorbidities. TTC patients had higher plasma concentrations of sTM: 7.94 (5.89;9.61) vs. 6.42 (5.50;7.82)ng/ml, p = 0.04 and ST2 (53 (32;157) vs. 45 (31;55)ng/ml, p = 0.008) and higher heart rate: 101 ([Formula: see text]33) vs. 76([Formula: see text]14)bpm, p = 0.0001, but lower concentrations of copeptin (10.4 (7.6;39) vs. 92.3 (13;197)pmol/l, p < 0.05) and troponin T (348 (98;759) vs. 1190 (261;4105)ng/l, p = 0.04).Conclusion: TTC patients had higher plasma concentrations of sTM and ST2, higher heart rate and lower copeptin and troponin T concentrations compared to acute anterior STEMI patients. This study contributes to the hypothesis that TTC patients have endothelial cell damage and are hemodynamically more stable than patients with acute anterior STEMI on admission.

Development of a severe mesenteric traction syndrome during major abdominal surgery is associated with increased postoperative morbidity: Secondary data analysis on prospective cohorts.

PURPOSE: MTS is elicited during open abdominal surgery and is characterized by facial flushing, hypotension, and tachycardia in response to the release of prostacyclin (PGI2) to plasma. MTS seems to affect postoperative morbidity, but data from larger cohorts are lacking. We aimed to determine the impact of severe mesenteric traction syndrome (MTS) on postoperative morbidity in patients undergoing open upper gastrointestinal surgery. METHODS: The study was a secondary analysis of data from three cohorts (n = 137). The patients were graded for severity of MTS intraoperatively, and hemodynamic variables and blood samples for plasma 6-keto-PGF1α, a stable metabolite of PGI2, were obtained at defined time points. Postoperative morbidity was evaluated by the comprehensive complication index (CCI) and the Dindo-Clavien classification (DC). RESULTS: Patients undergoing either esophagectomy (n = 70), gastrectomy (n = 22), liver- (n = 23), or pancreatic resection (n = 22) were included. Severe MTS was significantly associated with increased postoperative morbidity, i.e., CCI ≥ 26.2 (OR 3.06 [95% CI 1.1-6.6]; p = 0.03) and risk of severe complications, i.e., DC ≥3b (OR 3.1 [95% CI 1.2-8.2]; p = 0.023). Furthermore, patients with severe MTS had increased length of stay (OR 10.1 [95% CI 1.9-54.3]; p = 0.007) and were more likely to be admitted to the intensive care unit (OR = 7.3 [95% CI 1.3-41.9]; p = 0.027), but there was no difference in 1-year mortality. CONCLUSION: Occurrence of severe MTS during upper gastrointestinal surgery is associated with increased postoperative morbidity as indicated by an increased rate of severe complications, length of stay, and admission to the ICU. It remains to be determined whether inhibition of MTS enhances postoperative recovery.

[Diagnosing von Willebrand disease].

Von Willebrand disease (VWD) is an inherited bleeding disorder with abnormal primary haemostasis due to defects in, or decreased concentration of the glycoprotein von Willebrand factor. In Denmark, the estimated prevalence of VWD is 1% corresponding to approximately 50,000 patients, but only a few hundred have been diagnosed, mostly due to prolonged bleeding after a trauma or during surgery. Thus, VWD is underdiagnosed in the general population. Improved anamnestic screening for bleeding disorders such as VWD in certain high-risk groups can facilitate institution of prophylactic treatment.

Glucagon-like peptide-1: effect on pro-atrial natriuretic peptide in healthy males.

The antihypertensive actions of glucagon-like peptide-1 (GLP1) receptor agonists have been linked to the release of atrial natriuretic peptide (ANP) in mice. Whether a GLP1-ANP axis exists in humans is unknown. In this study, we examined 12 healthy young males in a randomized, controlled, double-blinded, single-day, cross-over study to evaluate the effects of a 2-h native GLP1 infusion. Plasma proANP concentrations were measured by an automated mid-region-directed proANP immunoassay and N-terminal pro B-type natriuretic peptide (BNP) on Roche Modular E170. Urine was collected for measurements of sodium excretion. Although GLP1 infusion increased the urinary sodium excretion markedly, there were no significant changes in either proANP or proBNP concentrations. When GLP1 infusion was stopped, sodium excretion declined rapidly. As proANP concentration reflects ANP secretion, our data could not confirm the existence of a GLP1-ANP axis in humans. Especially, the natriuretic effects of GLP1 seem unlikely to be mediated exclusively via ANP.

Congenital thrombotic thrombocytopenic purpura caused by new compound heterozygous mutations of the ADAMTS13 gene.

Upshaw-Schulman syndrome (USS) is due to severe congenital deficiency of von Willebrand factor (VWF)-cleaving protease ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 domains, nr 13) activity resulting in the presence of unusually large forms of VWF in the circulation, causing intravascular platelet clumping and thrombotic microangiopathy. Our patient, a 26-year-old man, had attacks of thrombotic thrombocytopenic purpura (TTP) with thrombocytopenia and a urine dipstick positive for hemoglobin (4+), often as the only sign of hemolytic activity. He had ADAMTS13 activity of <1% of normal plasma without the presence of inhibitors of ADAMTS13. ADAMTS13 deficiency was caused by two new mutations of the ADAMTS13 gene: a deletion of a single nucleotide in exon17 (c. 2042 delA) leading to a frameshift (K681C fs X16), and a missense mutation in exon 25 (c.3368G>A) leading to p.R1123H. This case report confirms the importance of the analysis of the ADAMTS13 activity and its inhibitor in patients who have episodes of TTP, with a very low platelet count and sometimes without the classic biochemical signs of hemolysis.

Copeptin during rest and exercise in major depression.

BACKGROUND: High vasopressin levels and a correlation between vasopressin and cortisol has been observed in patients with depression. The aim was to assess copeptin, the c-terminal of provasopressin, and the association between cortisol, adrenocorticotropic hormone (ACTH) and copeptin in patients with depression. Secondly, to examine the copeptin response to acute exercise and aerobic training. METHODS: Copeptin, ACTH, and cortisol were measured in 111 patients with depression and 57 controls at rest. Copeptin was also measured during exercise. The depressed patients were subsequently randomized to an aerobic training intervention or an exercise control intervention. RESULTS: The plasma level of copeptin in depressed subjects was 5.14 pg/ml (IQR 3.4-8.4) and 4.82 pg/ml (IQR 2.8-7.5) in healthy controls (p=.66). The association between copeptin and cortisol was.02 (95% CI -.44 to.48; p=.93) and the association between copeptin and ACTH was -.06 (95% CI -.17 to.05; p=.27). All associations were independent of depression status (p=.15). Aerobic exercise training did not influence copeptin levels at rest (p=.09) or the response to acute exercise (p=.574). Copeptin decreased at rest in response to aerobic training in participants with high compliance to the exercise intervention (p=.04). LIMITATIONS: We did not measure plasma osmolality, which is a possible confounder in this study. CONCLUSIONS: Copeptin levels are not elevated or associated to ACTH or cortisol in depressed patients. Aerobic exercise training decreased copeptin levels in high attenders only. This study does not support a role of copeptin or vasopressin in depression.

Troponin T is a strong marker of mortality in hospitalized patients.

BACKGROUND: Cardiac troponins are diagnostic markers in acute coronary syndrome and prognostic markers in stable coronary disease. Small increases are occasionally observed in patients with non-cardiac disease, but the prevalence and prognostic value of increased troponin in the general hospitalized population are unknown. METHODS: Consecutive patients aged >40 years admitted to a district hospital between 1 April 1998 and 31 March 1999 were included. A comprehensive medical interview and clinical examination were performed including echocardiography and measurement of natriuretic peptides and troponin T with a high-sensitivity assay (hs-TnT). RESULTS: Serum for analyses of hs-TnT was available from 1176 patients. Patients were 73.7 years old on average (interquartile range, 64.5-80.0 years), 59.2% were women and median follow-up was 11.4 years. The prevalence of elevated hs-TnT (> 99(th) percentile) was 57.1% of the entire cohort and 52.3% of patients with non-cardiac diagnoses. hs-TnT above the median (17 ng/L) was associated in univariate analysis with a 3-fold higher mortality in the entire population (multivariate hazard rate (HR) from 1.3 to 1.8 for 1 and 11 year mortality, respectively). In patients without past or present ischemic heart disease hs-TnT in the upper quartile (above 34.8 ng/L) was associated in univariate analysis with a 5-fold higher mortality risk (multivariable HR 1.8 to 2.2 for 1 and 11 year mortality, respectively). CONCLUSION: More than half of the hospitalized patients had hs-TnT levels above the 99(th) percentile. Elevated hs-TnT is a strong mortality risk marker in general hospitalized older patients.

Prevalence and prognosis of heart failure with preserved ejection fraction and elevated N-terminal pro brain natriuretic peptide: a 10-year analysis from the Copenhagen Hospital Heart Failure Study.

AIMS: The aim of this study was to assess the epidemiological features and prognosis of heart failure with preserved ejection fraction (HFPEF) and to compare these findings with those from patients with reduced ejection fraction. Furthermore the effects of N-terminal pro brain natriuretic peptide (NT-proBNP) requirement in the heart failure diagnosis were assessed by repeating the analyses in the subgroup of patients with elevated NT-proBNP. METHODS AND RESULTS: In 1844 patients admitted, a clinical diagnosis of heart failure was made in 433; amongst these 61% had HFPEF. An elevated NT-proBNP applied to the heart failure diagnosis reduced the number of heart failure patients to 191, and amongst these 29% had preserved ejection fraction. Use of NT-proBNP reduced clinical differences between heart failure patients with preserved and reduced ejection fraction. When not using NT-proBNP, patients with reduced ejection fraction had higher mortality [hazard ratio (HR) 1.24, 95% confidence interval (CI) 1.01-1.52; P = 0.04], even after adjustment for other significant predictors of mortality, except NT-proBNP (HR 1.29, 95% CI 1.04-1.59; P = 0.02). However, no difference in mortality was observed when NT-proBNP was adjusted for (HR 0.90, 95% CI 0.71-1.15; P = 0.4), or used for the heart failure diagnosis (HR 0.96; 95% CI 0.71-1.29; P = 0.8). CONCLUSION: Using a heart failure diagnosis requiring elevated NT-proBNP reduces the prevalence of HFPEF and results in a survival similar to that of heart failure with reduced ejection fraction. In contrast, when NT-proBNP is not used for the heart failure diagnosis or adjusted for, HFPEF is associated with a lower mortality in both univariate and multivariate analysis.

The influence of statin treatment on the inflammatory biomarkers YKL-40 and HsCRP in patients with stable coronary artery disease.

OBJECTIVE: The inflammatory biomarker YKL-40 is elevated and associated with mortality in patients with stable coronary artery disease (CAD). The aim was to investigate the influence of statin treatment and lipid status on serum YKL-40 and Hs-CRP in patients with stable CAD. DESIGN: Serum YKL-40, HsCRP, total cholesterol, HDL-c, LDL-c and triglycerides levels were measured in 404 statin treated and in 404 matched non-statin treated patients with stable CAD. RESULTS: YKL-40 was significantly higher in non-statin treated 110 µg/l (median) compared with 65 µg/l in statin treated (p < 0.001). HsCRP was 3.3 mg/l in non-statin treated compared with 2.1 mg/l in statin treated (p < 0.001). YKL-40 was not related to cholesterol levels for either statin or non-statin treated patients in the univariate analysis. In statin treated patients, HsCRP was related to a high level of total-cholesterol (p = 0.01) and a low level of HDL-c (p < 0.001). CONCLUSIONS: HsCRP, but not YKL-40, is associated with the cholesterol levels in statin treated patients. This indicates that YKL-40 could be a superior prognostic biomarker in patients with stable CAD, since it is independent of changes in cholesterol levels in both statin and non-statin treated patients.