Cer D18 Research Articles

A Novel Two-Lipid Signature Is a Strong and Independent Prognostic Factor in Ovarian Cancer.

Simple SummaryMost ovarian cancer patients initially show a response to primary treatments, but the development of refractory disease is a major problem. Currently, there are no blood-based prognostic biomarkers, and the prognosis of a patient is determined by the International Federation of Gynecology and Obstetrics (FIGO) stage and residual disease after cytoreductive surgery. In this study, we developed and validated a novel test based on the ratio of two circulatory lipids that enables the prognostic stratification of ovarian cancer patients at the time of diagnosis, prior to any oncological treatments. The translational relevance of this test is to find those patients with poor prognosis early on, and to identify patients that are at high risk of recurrence despite complete cytoreduction. Thus, the test enables the early direction of novel targeted therapies to those ovarian cancer patients at greatest risk of recurrence and death.Epithelial ovarian cancer (EOC) generally responds well to oncological treatments, but the eventual development of a refractory disease is a major clinical problem. Presently, there are no prognostic blood-based biomarkers for the stratification of EOC patients at the time of diagnosis. We set out to assess and validate the prognostic utility of a novel two-lipid signature, as the lipidome is known to be markedly aberrant in EOC patients. The study consisted of 499 women with histologically confirmed EOC that were prospectively recruited at the university hospitals in Turku (Finland) and Charité (Berlin, Germany). Lipidomic screening by tandem liquid chromatography–mass spectrometry (LC-MS/MS) was performed for all baseline serum samples of these patients, and additionally for 20 patients of the Turku cohort at various timepoints. A two-lipid signature, based on the ratio of the ceramide Cer(d18:1/18:0) and phosphatidylcholine PC(O-38:4), showed consistent prognostic performance in all investigated study cohorts. In the Turku cohort, the unadjusted hazard ratios (HRs) per standard deviation (SD) (95% confidence interval) were 1.79 (1.40, 2.29) for overall and 1.40 (1.14, 1.71) for progression-free survival. In a Charité cohort incorporating only stage III completely resected patients, the corresponding HRs were 1.59 (1.08, 2.35) and 1.53 (1.02, 2.30). In linear-mixed models predicting progression of the disease, the two-lipid signature showed higher performance (beta per SD increase 1.99 (1.38, 2.97)) than cancer antigen 125 (CA-125, 1.78 (1.13, 2.87)). The two-lipid signature was able to identify EOC patients with an especially poor prognosis at the time of diagnosis, and also showed promise for the detection of disease relapse.

CIRCULATING CERAMIDE AS A POTENTIAL BIOMARKER FOR ISOLATED NOCTURNAL HYPERTENSION

Objective: Isolated nocturnal hypertension (INH) is a subtype of hypertension characterized as an elevated blood pressure (BP) at nighttime only. To identify potential new biomarkers related with INH, we compared serum metabolite profiles between INH and normotensive controls. Design and method: Twenty-four-hour ambulatory BP monitoring was performed with Mobil-O-graph (IEM, Germany) monitors in untreated outpatients. INH was defined as a nocturnal BP greater or equal to 120/70 mmHg and daytime BP less than 135/85 mmHg at both two visits within a month. Age-sex matched normotensives (NT) were included as controls. We applied untargeted liquid chromatography tandem mass spectrometry (LC-MS) to detect serum metabolites. Multiple algorithms were first run in a training set (40 INH and 40 NT) and then in a test set (22 INH and 19 NT) to select and verify potential biomarkers. We computed student's P-values corrected by multiple comparison and VIP (Variable Importance in the Projection) score. Based on the results of untargeted LC-MS, we quantified 8 circulating sphingolipids, including sphingomyelin (SM) (d18:1/16:0), SM (d18:1/18:0), SM (d18:1/24:1), ceramide (Cer) (d18:1/16:0), Cer (d18:1/18:0), Cer (d18:1/24:1), sphingosine and sphingosine-1-phosphate in the test set by a targeted LC-MS method. Results: Orthogonal partial least squares-discriminant analysis (OPLS-DA) demonstrated a clear separation of metabolite profiles of INH patients from NT controls (R2 = 0.747, Q2 = 0.672). Cer (d18:1/16:0) had significant association with INH (odds ratio (OR) = 0.290 per SD, 95% confidence interval (CI), 0.125–0.715, P trend = 0.0027). The ceramide score, calculated as a sum of concentrations of the three ceramides, was associated with a lower risk of INH across extreme quartiles (OR = 0.592, 95% CI, 0.400–0.875, P trend = 0.0085). Moreover, Cer (18:1/16:0) significantly improved the diagnostic prediction of INH (P = 0.04). Conclusions: Our study illustrated a novel association between plasma ceramide concentration and INH. More research on ceramides in hypertensive pathobiology might be warranted.

Revealing serum lipidomic characteristics and potential lipid biomarkers in patients with POEMS syndrome.

POEMS syndrome is a rare plasma cell dyscrasia with distinct lipid metabolism abnormalities at disease onset. However, the serum lipidomic characteristics in patients with POEMS syndrome were not investigated. The study performed an untargeted lipidome screening by liquid chromatography‐tandem mass spectrometry (LS‐MS/MS) in the pre‐ and post‐treatment serum of 24 patients with POEMS syndrome, together with the serum of 24 paired healthy controls. Patients with POEMS syndrome had a distinct serum lipid composition compared with healthy controls, and a 3‐lipid model had a predictive accuracy of 93.5% in distinguishing patients and healthy controls consisting of fatty acyl 17‐oxo‐20Z‐hexacosenoic acid, phosphatidylcholine(16:0/18:1(9Z)) and sterol lipid 5b‐pregnanediol. Four lipids including 17‐oxo‐20Z‐hexacosenoic acid (r = 0.423, P = .040) were correlated with risk stratification, and 2 lipids including Cer(d18:0/13:0) were inversely related to serum vascular endothelial growth factor level (r=−0.465, P = .022). Eleven lipids were related to disease activity, including arachidonic acid which was inversely related and lysoPC(20:4) which was positively related. The study indicated a distinct lipid characteristic profile of patients with POEMS syndrome different from healthy controls and identified several lipids that may serve as potential diagnostic markers and monitors of therapeutic efficacy, as well as indicating potential metabolism pathways involved in the pathological process.

Lipid profiling of mouse intestinal organoids for studying APC mutations.

Inactivating mutations including both germline and somatic mutations in the adenomatous polyposis coli (APC) gene drives most familial and sporadic colorectal cancers. Understanding the metabolic implications of this mutation will aid to establish its wider impact on cellular behaviour and potentially inform clinical decisions. However, to date, alterations in lipid metabolism induced by APC mutations remain unclear. Intestinal organoids have gained widespread popularity in studying colorectal cancer and chemotherapies, because their 3D structure more accurately mimics an in vivo environment. Here, we aimed to investigate intra-cellular lipid disturbances induced by APC gene mutations in intestinal organoids using a reversed-phase ultra-high-performance liquid chromatography mass spectrometry (RP-UHPLC-MS)-based lipid profiling method. Lipids of the organoids grown from either wild-type (WT) or mice with APC mutations (Lgr5–EGFP-IRES-CreERT2 Apcfl/fl) were extracted and analysed using RP-UHPLC-MS. Levels of phospholipids (e.g. PC(16:0/16:0), PC(18:1/20:0), PC(38:0), PC(18:1/22:1)), ceramides (e.g. Cer(d18:0/22:0), Cer(d42:0), Cer(d18:1/24:1)) and hexosylceramides (e.g. HexCer(d18:1/16:0), HexCer(d18:1/22:0)) were higher in Apcfl/fl organoids, whereas levels of sphingomyelins (e.g. SM(d18:1/14:0), SM(d18:1/16:0)) were lower compared with WT. These observations indicate that cellular metabolism of sphingomyelin was up-regulated, resulting in the cellular accumulation of ceramides and production of HexCer due to the absence of Apcfl/fl in the organoids. Our observations demonstrated lipid profiling of organoids and provided an enhanced insight into the effects of the APC mutations on lipid metabolism, making for a valuable addition to screening options of the organoid lipidome.

Plasma ceramides are associated with outcomes in acute ischemic stroke patients

Sphingolipids are major constituents of eukaryotic cell membranes and play key roles in cellular regulatory processes. Our recent results in an experimental stroke animal model demonstrated changes in sphingolipids in response to acute ischemic brain injury. This study aimed to investigate the plasma levels of sphingosine-1-phosphate (S1P) and ceramides in acute ischemic stroke (AIS) patients and their associations with functional outcomes. Plasma samples were collected from patients with AIS at <48 and 48-72h post stroke and from nonstroke controls. The levels of S1P and ceramides with different fatty acyl chain lengths were measured by the ultra-high-pressure liquid chromatography-electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS). A poor functional outcome was defined as a modified Rankin Scale (mRS) score ≥2 at 3 months after AIS. The results showed that S1P and very-long-chain ceramides were significantly decreased in AIS patients (n=87; poor outcome, 56.3%) compared to nonstroke controls (n=30). In contrast, long-chain ceramides were significantly increased in AIS patients. More importantly, higher levels of Cer(d18:1/18:0), Cer(d18:1/20:0), and Cer(d18:1/22:0) at 48-72h were significantly associated with poor functional outcomes after adjusting for potential clinical confounders, including age, sex, hypertension, and National Institutes of Health Stroke Scale score at admission. Our study supported the dynamic metabolism of sphingolipids after the occurrence of AIS. Ceramides could be potential prognostic markers for patients with AIS.

Novel therapeutic evaluation biomarkers of lipid metabolism targets in uncomplicated pulmonary tuberculosis patients

Currently, the management of pulmonary tuberculosis (TB) lacks potent medications and accurate efficacy evaluation biomarkers. In view of the fact that the host lipids are the important energy source of Mycobacterium tuberculosis (Mtb), UPLC-MS/MS based on lipid metabolism was used to monitor the plasma lipid spectrum of TB patients from the initial diagnosis to cured. The analysis showed that TB patients presented aberrant metabolism of phospholipids, glycerides, and sphingolipids. Upon the treatment, the abnormal expression of Cer (d18:1/24:0), CerP (d18:1/20:3), LPE (0:0/22:0), LPA (0:0/16:0), and LPA (0:0/18:0) in TB patients were gradually normalized, indicating that the intervention of lipid metabolism could block energy metabolism and inhibit the cell wall synthesis of Mtb. Furthermore, the increase in ceramide (Cer) levels could promote autophagosome–lysosome fusion. LPA (0:0/16:0) and LPA (0:0/18:0) had a great potential in the early diagnosis (both sensitivity and specificity were 100%) and efficacy evaluation (both sensitivity and specificity were 100%) of TB, indicating that the above lipid metabolites could be used as potential biomarkers for TB.

Serum ceramides and type 2 diabetes are mutually independent predictors of cardiovascular events in patients with peripheral artery disease

Abstract Introduction: Ceramides are enriched in atherosclerotic plaques, and a set of circulating ceramides including Cer(d18:1/16:0), Cer(d18:1/18:0), Cer(d18:1/24:1), and Cer(d18:1/24:0) has recently emerged as predictors of cardiovascular outcomes in coronary artery disease patients. Hypothesis: We hypothesize that they have the power to predict cardiovascular events in patients with peripheral artery disease (PAD). Methods: We measured the serum concentrations of the above mentioned ceramides in a cohort of 380 patients with sonographically proven PAD, of whom 107 had type 2 diabetes (T2DM). Prospectively, we recorded 221 cardiovascular events over a mean follow-up time of 6.3±2.3 years. Results: Cardiovascular event risk was higher in T2DM patients than in those who did not have diabetes (69 vs. 52%, p=0.001). The ceramides Cer(18:1/16:0) and Cer(18:1/24:1) and the respective ratios Cer(18:1/16:0) / Cer(18:1/24:0) and Cer(18:1/24:1) / Cer(18:1/24:0) were significant predictors of cardiovascular events both univariately and after multivariate adjustment including the presence of T2DM (figure). Conversely, T2DM predicted cardiovascular events independently from the investigated ceramides (adjusted HR 1.76 [1.31-2.35], p<0.001). Conclusions: We conclude that the investigated ceramides and T2DM are mutually independent predictors of cardiovascular events in PAD patients.

Ceramide ratios are affected by cigarette smoke but not heat-not-burn or e-vapor aerosols across four independent mouse studies

AimsSmoking is an important risk factor for the development of chronic obstructive pulmonary disease and cardiovascular diseases. This study aimed to further elucidate the role of ceramides, as a key lipid class dysregulated in disease states. Main methodsIn this article we developed and validated LC–MS/MS method for ceramides (Cer(d18:1/16:0), Cer(d18:1/18:0), Cer(d18:1/24:0) and Cer(d18:1/24:1(15Z)) for the absolute quantification. We deployed it together with proteomics and transcriptomic analysis to assess the effects of cigarette smoke (CS) from the reference cigarette as well as aerosols from heat-not-burn (HnB) tobacco and e-vapor products in apolipoprotein E-deficient (ApoE−/−) mice over several time points. Key findingsIn the lungs, CS exposure substantially elevated the ratios of Cer(d18:1/24:0) and Cer(d18:1/24:1) to Cer(d18:1/18:0) in two independent ApoE−/− mouse inhalation studies. Data from previous studies, in both ApoE−/− and wild-type mice, further confirmed the reproducibility of this finding. Elevation of these ceramide ratios was also observed in plasma/serum, the liver, and—for the Cer(d18:1/24:1(15Z)) to Cer(d18:1/18:0) ratio—the abdominal aorta. Also, the levels of acid ceramidase (Asah1) and glucocerebrosidase (Gba)—lysosomal enzymes involved in the hydrolysis of glucosylceramides—were consistently elevated in the lungs after CS exposure. In contrast, exposure to HnB tobacco product and e-vapor aerosols did not induce significant changes in the ceramide profiles or associated enzymes. SignificanceOur work in mice contributes to the accumulating evidence on the importance of ceramide ratios as biologically relevant markers for respiratory disorders, adding to their already demonstrated role in cardiovascular disease risk assessment in humans.

Ceramide analog [18F]F-HPA-12 detects sphingolipid disbalance in the brain of Alzheimer\u2019s disease transgenic mice by functioning as a metabolic probe

The metabolism of ceramides is deregulated in the brain of Alzheimer’s disease (AD) patients and is associated with apolipoprotein (APO) APOE4 and amyloid-β pathology. However, how the ceramide metabolism changes over time in AD, in vivo, remains unknown. Distribution and metabolism of [18F]F-HPA-12, a radio-fluorinated version of the ceramide analog N-(3-hydroxy-1-hydroxymethyl-3-phenylpropyl) dodecanamide, was investigated in the brain of AD transgenic mouse models (FAD) on an APOE4 or APOE3 genetic background, by positron emission tomography and by gamma counter. We found that FAD mice displayed a higher uptake of [18F]F-HPA-12 in the brain, independently from the APOE4 or APOE3 genetic background. FAD mice could be distinguished from littermate control animals with a sensitivity of 85.7% and a specificity of 87.5%, by gamma counter measurements. Metabolic analysis of [18F]F-HPA-12 in the brain suggested that the tracer is degraded less efficiently in the FAD mice. Furthermore, the radioactive signal registered in the hippocampus correlated with an increase of Cer d18:1/20:2 levels measured in the same brain region by mass spectrometry. Our data gives additional proof that ceramide metabolism is different in FAD mice compared to controls. Ceramide analogs like HPA-12 may function as metabolic probes to study ceramide disbalance in the brain.

Investigation of lipid profile in Acetobacter pasteurianus Ab3 against acetic acid stress during vinegar production.

Elucidation of the acetic acid resistance (AAR) mechanisms of Acetobacter pasteurianus is significant for vinegar production. In this study, cell membrane lipid profile of A. pasteurianus Ab3 was investigated by gas chromatography-mass spectrometer (GC-MS) and high performance liquid chromatography-electrospray ionization (HPLC-ESI) combined with high resolution accurate mass/mass spectrometry (HRAM/MS). We observed that cell remodeled the membrane physical state by decreasing the ratio of saturated fatty acids (SFAs)/unsaturated fatty acids (UFAs), and increasing the chain length of fatty acids (FAs) and the content of cyclopropane FAs in response to extreme acid stress. Noticeably, the content of octadecadienoic acid (C18:2) elevated remarkably. Moreover, a continuous reduction in cell membrane fluidity and a "V-type" variance in permeability were discovered. The content of glycerophospholipid and ceramide increased significantly in cells harvested from culture with acidity of 75g/L and 95g/L compared to that with acidity of 30g/L. Among the identified lipid species, the content of phosphatidylcholine (e.g. PC 19:0/18:2 and 19:1/18:0), ceramide (e.g. Cer d18:0/16:1 and d18:0/16:1 + O), and dimethylphosphatidylethanolamine (e.g. dMePE 19:1/16:1) increased notably with increasing acidity. Collectively, these findings refresh our current understanding of the AAR mechanisms in A. pasteurianus Ab3, and should direct future strain breeding and vinegar fermentation.

Consistent alteration of chain length-specific ceramides in human and mouse fibrotic kidneys

BackgroundSeveral studies revealed alterations of single sphingolipid species, such as chain length-specific ceramides, in plasma and serum of patients with kidney diseases. Here, we investigated whether such alterations occur in kidney tissue from patients and mice suffering from renal fibrosis, the common endpoint of chronic kidney diseases. MethodsHuman fibrotic kidney samples were collected from nephrectomy specimens with hydronephrosis and/or pyelonephritis. Healthy parts from tumor nephrectomies served as nonfibrotic controls. Mouse fibrotic kidney samples were collected from male C57BL/6J mice treated with an adenine-rich diet for 14 days or were subjected to 7 days of unilateral ureteral obstruction (UUO). Kidneys of untreated mice and contralateral kidneys (UUO) served as respective controls. Sphingolipid levels were detected by LC-MS/MS. Fibrotic markers were analyzed by TaqMan® analysis and immunohistology. ResultsVery long-chain ceramides Cer d18:1/24:0 and Cer d18:1/24:1 were significantly downregulated in both fibrotic human kidney cortex and fibrotic murine kidney compared to respective control samples. These effects correlate with upregulation of COL1α1, COL3α1 and αSMA expression in fibrotic human kidney cortex and fibrotic mouse kidney. ConclusionWe have shown that very long-chain ceramides Cer d18:1/24:0 and Cer d18:1/24:1 are consistently downregulated in fibrotic kidney samples from human and mouse. Our findings support the use of in vivo murine models as appropriate translational means to understand the involvement of ceramides in human kidney diseases. In addition, our study raises interesting questions about the possible manipulation of ceramide metabolism to prevent progression of fibrosis and the use of ceramides as potential biomarkers of chronic kidney disease.

Circulating Ceramide: A New Cardiometabolic Biomarker in Patients With Comorbid Acute Coronary Syndrome and Type 2 Diabetes Mellitus.

AimsThis study investigated the association of circulating ceramides in patients with comorbid acute coronary syndrome and type 2 diabetes mellitus (ACS-DM).MethodsA total of 761 patients with coronary heart disease who were admitted to the Department of Cardiology at the Chinese PLA General Hospital from March to August 2018 were enrolled in this study. Of these 761 patients, 282 were diagnosed with acute coronary syndrome (ACS). We selected 65 patients with ACS-DM (ACS-DM group; mean age 64.88 years; 38 men) and 65 patients with ACS but without any comorbidities (ACS group; mean age 64.68 years; 38 men); the two groups were matched by age and sex. We determined four circulating ceramides in 130 plasma samples: Cer(d18:1/16:0), Cer(d18:1/18:0), Cer(d18:1/24:1), and Cer(d18:1/24:0). The ceramides in plasma samples from patients with ACS and those from patients with ACS-DM were compared. Pearson correlation coefficients between individual ceramides and traditional cardiovascular risk factors for the whole study population were calculated. Multiple logistic regression models were used to evaluate the relativity between the ceramide and ACS-DM.ResultsCompared with the ACS group, the levels of Cer(d18:1/16:0), Cer(d18:1/18:0), and Cer(d18:1/24:1) and their ratios to Cer(d18:1/24:0) were higher in the ACS-DM group and Cer(d18:1/24:0) was lower in the ACS-DM group (P < 0.05). Correlation analysis demonstrated mild-to-moderate correlations of ceramide and traditional cardiovascular risk factors. There were relatively strong correlations of Cer(d18:1/18:0) and Cer(d18:1/24:1) with C-reactive protein, blood lipids, fasting blood glucose, and glycated hemoglobin A1c. In multiple logistic regression models, Cer(d18:1/18:0) [odds ratio (OR) 2.396; 95% confidence interval (CI) 1.103–5.205; P = 0.027], Cer(d18:1/24:1) (OR 2.826; 95% CI 1.158–6.896; P = 0.023), Cer(d18:1/18:0)/Cer(d18:1/24:0) (OR 2.242; 95% CI 1.103–4.555; P = 0.026), and Cer(d18:1/24:1)/Cer(d18:1/24:0) (OR 2.673; 95% CI 1.225–5.836; P = 0.014) were positively correlated with ACS-DM, and Cer(d18:1/24:0) (OR 0.200; 95% CI 0.051–0.778; P = 0.020) was negatively correlated with ACS-DM.ConclusionCirculating ceramides are positively correlated with the risk of ACS-DM comorbidity. These results give a new insight into the pathogenesis of ACS-DM comorbidity and could provide new options for risk estimation.

Insights into the prognosis of lipidomic dysregulation for death risk in patients with coronary artery disease.

BackgroundDyslipidaemia contributes to the progression of coronary artery disease (CAD) toward adverse outcomes. Plasma lipidomic measure may improve the prognostic performances of clinical endpoints of CAD. Our research is designed to identify the correlations between plasma lipid species and the risks of death, major adverse cardiovascular event (MACE) and left ventricular (LV) remodeling in patients with CAD.MethodsA total of 1569 Chinese patients with CAD, 1011 single‐centre patients as internal training cohort, and 558 multicentre patients as external validation cohort, were enrolled. The concentration of plasma lipids in both cohorts was determined through widely targeted lipidomic profiling. Least absolute shrinkage and selection operator Cox and multivariate Cox regressions were used to develop prognostic models for death and MACE, respectively.ResultsTen (Cer(d18:1/20:1), Cer(d18:1/24:1), PE(30:2), PE(32:0), PE(32:2), PC(O‐38:2), PC(O‐36:4), PC(16:1/22:2), LPC(18:2/0:0) and LPE(0:0/24:6)) and two (Cer(d18:1/20:1) and LPC(20:0/0:0)) lipid species were independently related to death and MACE, respectively. Cer(d18:1/20:1) and Cer(d18:1/24:1) were correlated with LV remodeling (P < .05). The lipidic panel incorporating 10 lipid species and two traditional biomarkers for predicting 5‐year death risk represented a remarkable higher discrimination than traditional model with increased area under the curve from 76.56 to 83.65%, continuous NRI of 0.634 and IDI of 0.131. Furthermore, the panel was successfully used in differentiating multicentre patients with low, middle, or high risks (P < .0001). Further analysis indicated that the number of double bonds of phosphatidyl choline and the content of carbon atoms of phosphatidyl ethanolamines were negatively associated with death risk.ConclusionsImprovement in the prediction of death confirms the effectiveness of plasma lipids as predictors to risk classification in patients with CAD. The association between the structural characteristics of long‐chain polyunsaturated fatty acids and death risk highlights the need for mechanistic research that characterizes the role of individual lipid species in disease pathogenesis.

Plasma ceramides are associated with coronary atherosclerotic burden in patients with ST-segment elevation myocardial infarction

BackgroundPlasma ceramides (Cer), a subset of bioactive lipids, have mechanistic links to atherosclerotic coronary artery disease (CAD) pathogenesis and are related to major adverse cardiovascular events (MACEs). ObjectivesThis study aimed to explore the associations between plasma Cer and atherosclerotic burden evaluated by Synergy Between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery (SYNTAX) score. Methods and resultsA retrospective series of 248 ST-segment elevation myocardial infarction (STEMI) patients undergoing interventional procedures and plasma ceramides measurement were enrolled. Rapid resolution liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (RRLC-Q-TOF/MS) was used to evaluate plasma Cer concentrations. SYNTAX score was automatically calculated on the SYNTAX website (http://www.syntaxscore.com/). Patients with STEMI had higher plasma MACEs-related ceramide levels than normal donors (p < .001). Pearson correlation analysis showed positive correlations between SYNTAX score and Cer(d18:1/16:0) (r = 0.176, p = .006), Cer(d18:1/18:0) (r = 0.290, p < .001), Cer(d18:1/24:1) (r = 0.209, p = .001) and Cer(d18:1/24:0) (r = 0.134, p = .036). Adjustments for all traditional risks, higher Cer(d18:1/16:0) level (per SD increase, β (95%CI) =10.681 (1.912–19.923), p = .032), Cer(d18:1/18:0) level (per SD increase, β (95%CI) =38.830 (15.444–62.126), p = .001), Cer(d18:1/24:1) level (per SD increase, β (95%CI) =6.122 (1.640–10.605), p = .008) (except for and Cer(d18:1/24:0) level (per SD increase, β (95%CI) =0.999 (−0.508–2.506), p = .193)) were independently associated with higher levels of SYNTAX score. ConclusionsElevated plasma levels of Cer (d18:1/16:0), Cer(d18:1/18:0) and Cer(d18:1/24:1)) are independent predictors for a high atherosclerotic burden in patients with STEMI. Our findings provide evidence supporting proatherogenic roles of Cer.

Joint Synovial Fluid Metabolomics Method to Decipher the Metabolic Mechanisms of Adjuvant Arthritis and Geniposide Intervention.

Rheumatoid arthritis (RA), a chronic systemic autoimmune disease, is mainly characterized by joint lesions and permanent loss of joint function. To discover the metabolic characteristics of RA and the underlying mechanisms in treatment with geniposide (GE), untargeted metabolomic analysis based on hydrophilic interaction liquid chromatography coupled to high-resolution mass spectrometry (HILIC-HRMS) was performed using the joint synovial fluid samples from adjuvant arthritis (AA) rats. Microdialysis (MD) was utilized to collect the dialysate samples precisely from the articular cavity of AA rats. Multivariate statistical analysis was then conducted to discover the metabolite changes induced by AA and to differentiate GE-related biomarkers. The mass spectrometry data are available on the Chorus website (https://chorusproject.org/pages/index.html) with the data set identifier 1680. The results showed that 20 metabolites differed significantly between AA rats and normal rats. GE treatment recovered the altered levels of the 13 metabolites mentioned above, such as palmitoylethanolamide (PEA), Cer (d18:0/22:0), and PC (18:1(11Z)/16:1(9Z)), and normalized glycerophospholipid metabolism. As evidenced by western blotting, the changes in PEA levels adjusted by GE were associated with the down-regulated expression of N-acylethanolamine-hydrolyzing acid amidase (NAAA) in synovial tissues. Taken together, the elucidation of metabolic changes of joint synovial fluid and how this is influenced by GE will promote future therapeutic interventions of RA.

Gut Microbiome and Metabolome Were Altered and Strongly Associated With Platelet Count in Adult Patients With Primary Immune Thrombocytopenia.

Gut microbiota has been implicated in the pathogenesis of many autoimmune diseases. This is still an area of active research given that the role of gut microbiota on the primary immune thrombocytopenia (ITP) remains unclear. In this study, fecal samples of 30 untreated adult primary ITP patients and 29 healthy controls (HCs) were used to investigate the gut microbial community and metabolite profiles. Our results show that fecal bacteria such as Blautia, Streptococcus, and Lactobacillus are enriched, whereas bacteria such as Bacteroides are depleted in ITP patients. Notably, fecal metabolites such as fatty acyls and glycerophospholipids are enriched and strongly correlate with discrepant gut microbiota. Furthermore, combinations of Weissella and Streptococcus anginosus, or Cer (t18:0/16:0), Cer (d18:1/17:0), and 13-hydroxyoctadecanoic acid could provide good diagnostic markers for ITP. Moreover, a strong negative correlation was found between platelet count and altered gut microbiota such as S. anginosus and gut metabolites such as Cer (t18:0/16:0) in ITP. In conclusion, dysbiosis of both gut microbiota and metabolome develops in ITP patients compared to HCs. Several ITP-altered gut bacteria and metabolites can be diagnostic biomarkers for ITP, and are highly correlated with platelet count, suggesting that they may also play a role in ITP pathogenesis.

Relation between plasma ceramides and cardiovascular death in chronic heart failure: A subset analysis of the GISSI-HF trial.

AimsCeramides exert several biological activities that may contribute to the pathophysiology of cardiovascular disease and heart failure (HF). The association between plasma levels of distinct ceramides (that have been previously associated with increased cardiovascular risk) and cardiovascular mortality in patients with chronic HF has received little attention.Methods and resultsIn a post hoc ancillary analysis of the Gruppo Italiano per lo Studio della Sopravvivenza nella Insufficienza Cardiaca‐Heart Failure (GISSI‐HF; NCT00336336) trial, we randomly selected a sample of 200 ambulatory patients with chronic HF who died due to cardiovascular causes and 200 patients who were alive at the end of the trial (after a median follow‐up period of 3.9 years). We measured baseline plasma concentrations of six previously identified high‐risk ceramide species [Cer(d18:1/16:0), Cer(d18:1/18:0), Cer(d18:1/20:0), Cer(d18:1/22:0), Cer(d18:1/24:0), and Cer(d18:1/24:1) and their individual plasma ratios with Cer(d18:1/24:0)]. Patients who died due to cardiovascular causes had significantly (P < 0.05 or less) higher levels of plasma Cer(d18:1/16:0) and Cer(d18:1/24:1), but lower levels of plasma Cer(d18:1/22:0) and Cer(d18:1/24:0) than had those who did not. All plasma ratios of each ceramide with Cer(d18:1/24:0) were significantly higher in patients who died due to cardiovascular causes. In Cox regression analyses, all five plasma ratios of each ceramide with Cer(d18:1/24:0) were significantly associated with a greater risk of cardiovascular mortality (with unadjusted hazard ratios ranging from 1.23 to 1.59; P < 0.001 or less). These significant associations were attenuated after adjustment for multiple established risk factors, New York Heart Association functional class, left ventricular ejection fraction, use of medications, plasma pentraxin‐3 levels, and, especially, plasma N‐terminal pro‐brain natriuretic peptide (NT‐proBNP) levels. When we applied a Bonferroni correction for multiple comparisons (using a P‐threshold 0.05/5 ceramide ratios = 0.01), none of the five plasma ratios of each ceramide with Cer(d18:1/24:0) remained statistically associated with the risk of cardiovascular mortality (with adjusted hazard ratios ranging from 1.10 to 1.23).ConclusionsHigher levels of specific plasma ceramides [especially when used in ratios with Cer(d18:1/24:0)] are associated with increased cardiovascular mortality in ambulatory patients with chronic HF. However, these associations are weakened after adjustment for established cardiovascular risk factors, medication use, and plasma NT‐proBNP concentrations.

Alterations in plasma triglycerides and ceramides: links with cardiac function in humans with type 2 diabetes

Cardiac dysfunction in T2D is associated with excessive FA uptake, oxidation, and generation of toxic lipid species by the heart. It is not known whether decreasing lipid delivery to the heart can effect improvement in cardiac function in humans with T2D. Thus, our objective was to test the hypothesis that lowering lipid delivery to the heart would result in evidence of decreased "lipotoxicity," improved cardiac function, and salutary effects on plasma biomarkers of cardiovascular risk. Thus, we performed a double-blind randomized placebo-controlled parallel design study of the effects of 12 weeks of fenofibrate-induced lipid lowering on cardiac function, inflammation, and oxidation biomarkers, and on the ratio of two plasma ceramides, Cer d18:1 (4E) (1OH, 3OH)/24:0 and Cer d18:1 (4E) (1OH, 3OH)/16:0 (i.e., "C24:0/C16:0"), which is associated with decreased risk of cardiac dysfunction and heart failure. Fenofibrate lowered plasma TG and cholesterol but did not improve heart systolic or diastolic function. Fenofibrate treatment lowered the plasma C24:0/C16:0 ceramide ratio and minimally altered oxidative stress markers but did not alter measures of inflammation. Overall, plasma TG lowering correlated with improvement of cardiac relaxation (diastolic function) as measured by tissue Doppler-derived parameter e'. Moreover, lowering the plasma C24:0/C16:0 ceramide ratio was correlated with worse diastolic function. These findings indicate that fenofibrate treatment per se is not sufficient to effect changes in cardiac function; however, decreases in plasma TG may be linked to improved diastolic function. In contrast, decreases in plasma C24:0/C16:0 are linked with worsening cardiac function.

Association between ceramides and coronary artery stenosis in patients with coronary artery disease

BackgroundCoronary artery stenosis induces heart diseases including acute coronary syndrome (ACS). Some studies reported the ceramide species are associated with the ACS and major adverse cardia and cerebrovascular events (MACE). However, few studies investigated the association between plasma ceramide levels and the severity of stenosis, together with the onset of diseases. This aim of the present study was to investigate the association betweencertain ceramide species, coronary artery stenosis and acute coronary syndrome.MethodsFive hundred fifty-three patients with definite or suspected CAD were recruited and received angiography. Subjects were assigned into 4 groups according to the severity of coronary artery stenosis. The measurements of 4 plasma ceramide species, namely, Cer (d18:1/16:0), Cer (d18:1/18:0), Cer (d18:1/24:1), Cer (d18:1/24:0) were carried out by Liquid chromatography-tandem mass spectrometry (LC-MS/MS) and the ratio of Cer (d18:1/16:0), Cer (d18:1/18:0) and Cer (d18:1/24:1) to Cer (18:1/24:0), respectively, were calculated as index to evaluate the association between plasma ceramides levels and coronary artery stenosis. Multiple logistic regression analysis was used to establish the prognostic model for the prediction of ACS risk.ResultsAfter the adjustment by multiple clinical risk factors including age, gender, pre-existing myocardial/cerebral infarction, hemoglobin A1c% (HbA1c%), smoking and the diagnosis during index hospitalization, multiple logistic regression analysis showed that the high ratio of Cer (d18:1/24:1) to Cer (d18:1/24:0), female gender, HbA1c%, unstable angina (UAP) and acute myocardial infarction (AMI) diagnosis (compared with atherosclerosis) during index hospitalization were associated with more severe coronary artery stenosis. Furthermore, the prognostic model was established after adjustment of risk factors and the area under curve (AUC) of receiver operating characteristics (ROC) for the prognostic model was 0.732 and 95% CI was 0.642–0.822.ConclusionThe severity of coronary artery stenosis is associated with high ratio of Cer (d18:1/24:1) to Cer (d18:1/24:0), female gender, HbA1c% and AMI. Although the reported prognostic model showed a good discrimination, further investigation on long term MACE is needed to evaluate the role of ceramide for the prediction of MACE risk.

Clinical significance of circulating tumor cells and metabolic signatures in lung cancer after surgical removal

BackgroundLung cancer (LC) remains the deadliest form of cancer globally. While surgery remains the optimal treatment strategy for individuals with early-stage LC, what the metabolic consequences are of such surgical intervention remains uncertain.MethodsNegative enrichment-fluorescence in situ hybridization (NE-FISH) was used in an effort to detect circulating tumor cells (CTCs) in pre- and post-surgery peripheral blood samples from 51 LC patients. In addition, targeted metabolomics analyses, multivariate statistical analyses, and pathway analyses were used to explore surgery-associated metabolic changes.ResultsLC patients had significantly higher CTC counts relative to healthy controls with 66.67% of LC patients having at least 1 detected CTC before surgery. CTC counts were associated with clinical outcomes following surgery. In a targeted metabolomics analysis, we detected 34 amino acids, 147 lipids, and 24 fatty acids. When comparing LC patients before and after surgery to control patients, metabolic shifts were detected via PLS-DA and pathway analysis. Further surgery-associated metabolic changes were identified when comparing LA (LC patients after surgery) and LB (LC patients before surgery) groups. We identified SM 42:4, Ser, Sar, Gln, and LPC 18:0 for inclusion in a biomarker panel for early-stage LC detection based upon an AUC of 0.965 (95% CI 0.900–1.000). This analysis revealed that SM 42:2, SM 35:1, PC (16:0/14:0), PC (14:0/16:1), Cer (d18:1/24:1), and SM 38:3 may offer diagnostic and prognostic benefits in LC.ConclusionsThese findings suggest that CTC detection and plasma metabolite profiling may be an effective means of diagnosing early-stage LC and identifying patients at risk for disease recurrence.