Nascent MetS Research Articles

An Increasing Triglyceride-Glucose Index Is Associated with a Pro-Inflammatory and Pro-Oxidant Phenotype.

Background/Objectives: Insulin resistance is crucial in the pathogenesis of Metabolic Syndrome (MetS), type 2 diabetes mellitus (T2DM) and premature atherosclerotic cardiovascular disease (ASCVD). The triglyceride-glucose index (TyG index), a validated measure of insulin resistance, also predicts MetS, T2DM, the severity of albuminuria and ASCVD. There are scant data providing mechanistic insights into these sequalae. Accordingly, we investigated the relationship between the TyG index and biomarkers of inflammation, oxidative stress, free fatty acid (FFA) levels and adipokine dysregulation in a cohort comprising both controls and patients with nascent MetS. Methods: Participants (n = 102) included 59 patients with MetS and 43 controls. People with diabetes, ASCVD, smoking and macro-inflammation were excluded. Fasting blood was obtained for both plasma and monocyte isolation. Results: Receiver Operating Characteristic (ROC) curve analysis revealed that the TyG index was an excellent predictor of MetS with an area under the curve of 0.87, and it correlated with both hepatic and adipose tissue insulin resistance. Both serum RBP-4 levels and non-HDL cholesterol increased significantly over tertiles of the TyG index. Based on the TyG index tertiles and/or correlations, oxidized LDL, nitrotyrosine, C-reactive protein, endotoxin, chemerin, interleukin-6 levels and monocyte toll-like receptor (TLR)-4 and TLR-2 and their cellular signaling were significantly associated with the TyG index. Conclusions: Increased non-HDL-C and, most importantly, a pro-inflammatory and pro-oxidant state could be advanced as potential mechanisms explaining the increased risk for T2DM and ASCVD with an increasing TyG index.

Increased Adipocyte Hypertrophy in Patients with Nascent Metabolic Syndrome.

Background and Aims: Metabolic Syndrome (MetS), a global problem, predisposes to an increased risk for type 2 diabetes and premature cardiovascular disease. While MetS is associated with central obesity, there is scanty data on adipocyte hypertrophy, increased fat cell size (FCS), in MetS. The aim of this study was to investigate FCS status in adipose tissue (AT) biopsy of patients with nascent MetS without the confounding of diabetes, cardiovascular disease, smoking, or lipid therapy. Methods and Results: Fasting blood and subcutaneous gluteal AT biopsies were obtained in MetS (n = 20) and controls (n = 19). Cardio-metabolic features, FFA levels, hsCRP, and HOMA-IR were significantly increased in patients with MetS. Waist-circumference (WC) adjusted-FCS was significantly increased in patients with MetS and increased with increasing severity of MetS. Furthermore, there were significant correlations between FCS with glucose, HDL-C, and the ratio of TG: HDL-C. There were significant correlations between FCS and FFA, as well as endotoxin and monocyte TLR4 abundance. Additionally, FCS correlated with readouts of NLRP3 Inflammasome activity. Most importantly, FCS correlated with markers of fibrosis and angiogenesis. Conclusions: In conclusion, in patients with nascent MetS, we demonstrate WC-adjusted increase in FCS from gluteal adipose tissue which correlated with cellular inflammation, fibrosis, and angiogenesis. While these preliminary observations were in gluteal fat, future studies are warranted to confirm these findings in visceral and other fat depots.

Correlates of Insulin Resistance in Nascent Metabolic Syndrome.

Metabolic Syndrome (MetS), a major global problem, is a cluster of cardio-metabolic risk factors that predisposes to both type 2 diabetes mellitus (T2DM) and premature atherosclerotic cardiovascular disease (ASCVD). Insulin resistance is a major underpinning of MetS. We investigated the relationship between insulin resistance and biomarkers of inflammation, oxidative stress, free fatty acids (FFA) levels and adipokine dysregulation in a cohort of nascent MetS. This was a cross-sectional study comparing patients with MetS with matched controls. Participants included 47 patients with MetS and 41 controls. Persons with diabetes, ASCVD, smoking and macro-inflammation were excluded. Fasting blood was obtained for both plasma and monocyte isolation. Homeostasis model assessment insulin resistance index (HOMA-IR) was calculated from fasting glucose and insulin levels. The patients were insulin resistant as determined by a valid measure, HOMA-IR. HOMA-IR increased with increasing severity of MetS and correlated with cardio-metabolic features, hsCRP, FFA levels, and adipose tissue insulin resistance. Insulin resistance also correlated with biomarkers of oxidative stress and both circulating and cellular biomarkers of inflammation. Receiver operating Characteristic (ROC) curve analysis revealed that HOMA-IR was an excellent predictor of MetS with an area under the curve of 0.80. In our patients with nascent MetS we show that they have significant insulin resistance. Based on our findings, elevated FFA levels, oxidative stress and inflammation could contribute to the insulin resistance.

Relationship between circulating serum omentin-1 levels and nascent metabolic syndrome in patients with hypertension

The prevalence of metabolic syndrome (MetS) is more common in patients with hypertension and is associated with an increased risk of target organ damage and/or cardiovascular disease (CVD). Omentin-1 is...

The Ratios of Triglycerides and C-reactive protein to High density-lipoprotein -cholesterol as valid biochemical markers of the Nascent Metabolic Syndrome

ABSTRACT Aims: Metabolic syndrome (MetS), a cardiometabolic cluster, is a major global problem. The ratio of triglycerides (TG) to high-density lipoprotein cholesterol (HDL-C) is a good biomarker of MetS in certain populations C-reactive protein (CRP) has also been also shown to be a biomarker of MetS. Since CRP captures inflammation, we compared the ratios of TG to HDL-C and CRP to HDL-C in patients with nascent MetS. Methods: Patients with MetS (n = 58) and matched controls (n = 44) were recruited. Fasting blood samples were obtained for routine laboratories, insulin, and adipokines. TG and CRP ratios to HDL-C were calculated. Data were analyzed statistically. Results: Both the TG to HDL-C and CRP to HDL-C ratios were significantly increased in MetS and both increased with increasing severity of MetS. Whilst both correlated with cardiometabolic features and insulin resistance, only the CRP to HDL-C ratio correlated significantly with adiponectin and leptin. Receiver operating characteristic curve analysis showed that both ratios showed excellent discrimination for MetS with no significant differences between ratios. Conclusions: Thus both the TG to HDL-C and CRP to HDL-C ratios are significantly increased in patients with nascent MetS and appear to be valid biomarkers of MetS. However, these preliminary findings with CRP: HDL-C need confirmation in large prospective studies and could have important implications for assessing cardiometabolic risk in African Americans, an under-served population.

Metabolites that activate the inflammasome in nascent metabolic syndrome.

Metabolic Syndrome (MetS) is a cardio-metabolic cluster that increases the risk of type 2 diabetes mellitus (T2DM) and atherosclerotic cardiovascular disease (ASCVD). Whilst it affects 35% of the American adult population, its pathogenesis remains to be elucidated. Both insulin resistance and increased inflammation appear to be pivotal mechanisms. The NOD-like receptor family pyrin domain containing protein 3 (NLRP3) inflammasome, an intracellular multi-protein complex, is crucial in the activation of Caspase 1, resulting in an increase in both IL-1and IL-18. In this preliminary report we examined the relationship between metabolites from our exploratory metabolomics studies with the NLRP3 inflammasome activity in the adipose tissue of patients with nascent MetS. This study comprised patients with nascent MetS matched with controls. All patients in this study had normal renal and hepatic function. Metabolites were analyzed from frozen early morning urine samples and correlated with adipose tissue Caspase 1, interleukin-1, and interleukin-18 density. Caspase 1, a marker of NLRP3 inflammasome activity, was significantly elevated in patients with nascent MetS compared to controls. Isoleucine, GABA, Carnitine and PC34: 2 were also significantly increased in patients with MetS. Caspase1 correlated positively with Isoleucine, GABA, Carnitine, and PC34:2. We make the novel observation that the NLRP3 inflammasome activity is correlated with certain metabolites (Isoleucine, GABA, Carnitine and PC34:2) and hypothesize that they could trigger increased NLRP3 Inflammasome activity in MetS. However, these preliminary ,hypothesis generating novel findings need confirmation in larger studies of the metabolome and inflammasome.

The platelet to high density lipoprotein -cholesterol ratio is a valid biomarker of nascent metabolic syndrome.

The metabolic syndrome (MetS) is a major global problem, and inflammation and insulin resistance appear to be key underpinnings in this cardio-metabolic cluster. MetS predisposes to an increased risk of diabetes and atherosclerotic cardiovascular disease (ASCVD). It has a procoagulant diathesis which included increased platelet activity and impaired fibrinolysis. High density lipoprotein (HDL) appears to be anti-thrombotic. Accordingly, we examined the ratios between platelets to HDL-cholesterol(C) and adiponectin (Adipo) in patients with nascent MetS without the confounding of diabetes, ASCVD and smoking to determine their validity as biomarkers of MetS. Patients with nascent MetS (n = 58) and matched controls (n = 44) were recruited. Fasting blood samples were obtained for complete blood counts, basic metabolic panel, lipids, insulin, and Adipo. Ratios of platelets to HDL-C and Adipo were calculated. Following adjustment for adiposity, only the platelet: HDL ratio was significantly increased in MetS and increased with severity of MetS. Receiver operating characteristic curve analysis showed that the platelet: HDL-C area under the curve (AUC) significantly added to both platelets and platelet lymphocyte ratio AUCs. Also the platelet: HDL-C ratio correlated with all cardio-metabolic features of MetS, high sensitivity C-reactive protein, insulin resistance chemerin, and leptin. The ratio of platelets: HDL-C is significantly increased in patients with nascent MetS and appear to be a valid biomarker of MetS. It could also emerge as a biomarker for athero-thrombotic risk. However, these preliminary findings need confirmation in large prospective studies.

Chemerin Ratios to HDL-cholesterol and Adiponectin as Biomarkers of Metabolic Syndrome

ABSTRACT Aims Metabolic Syndrome (MetS) a global problem, which comprises a cardio-metabolic cluster of risk factors, increases the risk for type-2 diabetes (T2DM) and atherosclerotic cardiovascular diseases (ASCVD). To date, the best laboratory-based biomarker for MetS appears to be high-sensitivity C-reactive protein (hsCRP). Chemerin, a novel adipokine is increased in MetS and appears to contribute to both insulin resistance and inflammation. In this pilot study, we tested if the chemerin:HDL-C or chemerin:adiponectin ratios are better biomarkers for predicting MetS than hsCRP. Patients and Methods We enrolled patients and controls with nascent MetS, uncomplicated by diabetes, ASCVD, macro-inflammation, and smoking using rigorous criteria. Fasting blood samples were obtained in order to calculate insulin resistance in the liver (HOMA-IR) and adipose tissue (ADIPO-IR) and for measurement of chemerin and adiponectin levels. Statistical analyses including receiver operating characteristic (ROC) curves were used to evaluate data. Results We observed the chemerin:HDL-C ratio is significantly increased in MetS and increases with severity of MetS (p < .001). The chemerin: adiponectin ratio was not significantly increased following adjustment for age and waist circumference. The chemerin:HDL-C ratio correlated with BMI, WC, triglycerides, plasma glucose, HDL-C, and both HOMA-IR and ADIPO-IR. ROC curve analysis showed that the chemerin:HDL-C ratio area under the curve (AUC) was greater than the AUC for hsCRP. Conclusion In this preliminary report, we demonstrate that the ratio of chemerin to HDL-C is a valid biomarker of MetS and appears to be a better predictor than hsCRP. These findings need to be confirmed in larger studies.

Increased inflammasome activity in subcutaneous adipose tissue of patients with metabolic syndrome.

The metabolic syndrome (MetS) is an inflammatory disorder associated with an increased risk for diabetes and atherosclerotic cardiovascular disease (ASCVD). Studies in patients and animal models of obesity and diabetes have shown increased NOD-like receptor family pyrin domain containing 3 (NLPR3) inflammasome activity. However, there is scanty data on the activity of the NLRP3 inflammasome in patients with nascent MetS. The aim of this study was to determine the status of the inflammasome in subcutaneous adipose tissue (SAT) of patients with nascent MetS without concomitant diabetes, ASCVD and smoking. Patients with nascent MetS and controls were recruited from Sacramento County. Fasting blood samples were collected for biomediators of inflammation and SAT was obtained by biopsy for immunohistochemical (IHC) staining for caspase 1, IL-1β and IL-18. Caspase1, a marker of inflammasome activity and its downstream mediators IL-1β and IL-18 were significantly increased in SAT of patients with MetS compared to controls. Significant positive correlations of caspase 1 were obtained with certain cardio-metabolic features, biomediators of inflammation and markers of angiogenesis and fibrosis in SAT. Both mast cell and eosinophil abundance but not macrophage density correlated with caspase1. We make the novel observation that the SAT of patients with nascent MetS displays increased NLRP3 inflammasome activity manifest by increased caspase 1 in SAT and this may contribute to increased insulin resistance, inflammation and SAT fibrosis in these patients.

SAT-656 Both Neutrophil and Monocyte Ratios to High Density Lipoprotein Cholesterol Are Superior Biomarkers of Metabolic Syndrome

Metabolic Syndrome (MetS) continues to be a significant problem globally, affecting nearly 35% of adults in the USA. Whilst there is no ideal biomarker that captures this disorder high sensitivity C-reactive protein (hsCRP) is the most widely accepted measure.We examined the ratios between the phagocytes, neutrophils(PMN)and monocytes, to high density lipoprotein (HDL) and adiponectin, two anti-inflammatory proteins, in patients with nascent MetS without the confounding of T2DM, ASCVD, smoking or lipid therapy to determine if they were valid biomarkers of MetS. Patients with nascent MetS(n=58) and matched controls(n=44) were recruited from Sacramento County. Patients with diabetes, cardiovascular diseases, inflammation (hsCRP >10mg/L or leukocytosis), smoking, anti-inflammatory and hypolipidemic drug therapies were excluded. Fasting blood samples were obtained for complete blood counts, basic metabolic panel, lipid profile, insulin adiponectin, leptin and chemerin. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated from glucose and insulin levels. Ratios of PMN and monocytes to HDL-C and Adiponectin were calculated and compared statistically. PMN: HDL-C and Monocyte: HDL-C, increased in patients with MetS compared to controls (p<0.0001 and p=0.001 respectively).Also the PMN: Adiponectin and monocyte: Adiponectin ratios were significantly increased in MetS (p=0.006 and 0.02 respectively). All ratios increased with increasing severity of MetS (p=0.01). Receiver Operating Characteristic (ROC) curve analysis showed that both the PMN/HDL-C and monocyte: HDL-C area under the curve(AUC)(0.85 and 0.84 respectively) significantly added to the CRP AUC(0.75), p=0.01 for both. Neither leukocyte: Adiponectin AUC was significant compared to hsCRP. Also both ratios to HDL-C correlated with cardio-metabolic features of MetS, hsCRP and insulin resistance(HOMA-IR) (p<0.05). Whilst the PMN:HDL-C ratio correlated with leptin, and chemerin the monocyte: HDL-C ratio correlated significantly with chemerin only (p<0.05) Our cross-sectional study indicates that ratios of neutrophils and monocytes to HDL-C are significantly increased in patients with nascent MetS, increase with severity of MetS, correlate positively with inflammation and insulin resistance and both ratios appear to be better predictors of MetS than hsCRP. In conclusion, they provide a cost-effective measure of Metabolic Syndrome and should be confirmed in larger data bases and prospective studies.

Decreased homoserine levels in metabolic syndrome

Background and aimsThe pathogenesis Metabolic Syndrome (MetS), a common global problem, remains to be elucidated. As part of our exploratory metabolomics research we determined if homoserine levels are an early biomarker of nascent MetS. MethodsAn exploratory study involving 28 patients with nascent MetS and 20 matched controls. Metabolites were studied from early morning urine samples and assayed by the NIH Western Metabolomics Center using gas chromatography time-of-flight mass spectrometry and were standardized to urine creatinine. All of the patients enrolled in the study had normal renal and hepatic function. ResultsPatients with MetS had statistically significant increases in overall waist circumference, blood pressure, glucose, HOMA-IR, HbA1C in comparison to the control group. Additionally, increases in IL-1b, IL-6, TLR-4, endotoxin, and leptin were also seen in the MetS group subjects compared to the control group. The concentrations of homoserine were significantly decreased 3-fold in patients with MetS in comparison to the matched controls, p = 0.0027. Furthermore, levels of homoserine were inversely correlated to multiple biomarkers of inflammation and cardio-metabolic risk factors such as HbA1C, blood pressure, TLR-4, leptin, endotoxin, and SAT secreted fetuin A. In addition, homoserine was positively correlated with lysine and NAT. ConclusionsIn conclusion, low levels of homoserine could potentially contribute to the proinflammatory state in MetS.

Neutrophil and monocyte ratios to high-density lipoprotein-cholesterol and adiponectin as biomarkers of nascent metabolic syndrome.

Background Metabolic syndrome (MetS) continues to be a significant problem globally, affecting nearly 35% of adults in the USA. Whilst there is no ideal biomarker that captures this disorder, high sensitivity C-reactive protein (hsCRP) appears to be most widely accepted. We examined the ratios between neutrophils (PMNs) and monocytes to high-density lipoprotein (HDL)-cholesterol and adiponectin, two anti-inflammatory proteins, in patients with nascent MetS without the confounding of diabetes, atherosclerotic cardiovascular diseases (ASCVD), smoking or lipid therapy to determine if they were also valid biomarkers of MetS. Materials and methods Patients with nascent MetS (n = 58) and matched controls (n = 44) were recruited from Sacramento County. Fasting blood samples were obtained for complete blood counts, basic metabolic panel, lipid profile, insulin and adiponectin. Ratios of PMNs and monocytes to HDL-C and adiponectin were calculated and compared statistically. Results The PMN:HDL-C, monocyte:HDL-C, PMN:adiponectin and monocyte:adiponectin ratios were significantly increased in patients with MetS and increased with increasing severity of MetS. Receiver operating characteristic (ROC) curve analysis showed that both the PMN:HDL-C and monocyte:HDL-C areas under the curve (AUCs) significantly added to the CRP AUC. Also both the ratios correlated with cardio-metabolic features of MetS, hsCRP and insulin resistance. Conclusions Our data indicates that ratios of neutrophils and monocytes to HDL-C are significantly increased in patients with nascent MetS and both ratios appear to be better predictors of MetS than hsCRP alone. These important preliminary findings need to be confirmed in large prospective databases.

The relationship between tyramine levels and inflammation in metabolic syndrome.

Background Metabolic syndrome (MetS) is an important contributor to both type 2 diabetes mellitus (T2DM) and atherosclerotic cardiovascular disease (ASCVD). Although MetS affects one third of American adults, its pathogenesis remains to be elucidated. Tyramine, a derivative of tyrosine, has been shown to act as a catecholamine releasing agent in the human body. The aim of this study is to investigate the role of tyramine as an early biomarker for nascent MetS without the confounding of T2DM, ASCVD or smoking. Patients and methods This was an exploratory study of 28 patients with nascent MetS and 20 matched controls carried out in 2018. Metabolites were evaluated from patient's frozen early morning urine samples and were correlated with biomarkers of inflammation and adipokines. They were assayed by the National Institutes of Health (NIH) Western Metabolomics Center using liquid chromatography/mass spectrometry (LC/MS) and standardized to urinary creatinine. All patients had normal hepatic and renal function. Results Tyramine concentrations were significantly reduced in patients with MetS compared to controls, p = 0.0009. In addition, tyramine was significantly inversely correlated with multiple biomarkers of inflammation and cardiometabolic risk factors such as RBP4, monocyte TLR-4 abundance and P38MAPKinase activity, body mass index (BMI) and blood pressure (BP) (both systolic and diastolic). Conclusion In conclusion, low levels of tyramine could contribute to the proinflammatorty state of MetS.

Exploratory metabolomics of nascent metabolic syndrome

IntroductionMetabolic syndrome (MetS) is a disorder defined by having three of five features: increased waist circumference (WC), hypertriglyceridemia, decreased high-density lipoprotein-cholesterol, hypertension and an elevated blood glucose (BG). Metabolic Syndrome ( MetS) affects 35% of American adults and significantly increases risk for Atherosclerotic cardiovascular disease (ASCVD) and type-2 diabetes (T2DM). An understanding of the metabolome will help elucidate the pathogenesis of MetS and lead to better management. We hypothesize that the metabolites, gamma-aminobutyric acid (GABA), d-pyroglutamic acid (PGA) and N-acetyl-d-tryptophan (NAT) will be altered in nascent MetS patients without the confounding of ASCVD or T2DM. We also correlated these metabolites with biomarkers of inflammation. Patients and methodsThis was an exploratory study of 30 patients with nascent MetS and 20 matched controls undertaken in 2018.Metabolites were evaluated from patient's frozen early morning urine samples and were correlated with biomarkers of inflammation and adipokines. They were assayed by the NIH Western Metabolomics Center using liquid chromatography/mass spectrometry and standardized to urinary creatinine. All patients had normal hepatic and renal function. ResultsGABA and PGA levels were significantly increased in MetS patients compared to controls: 2.8-fold and 2.9-fold median increases respectively with p < 0.0001 and p = 0.004, possibly deriving from glutamate. NAT was significantly decreased by 90% in MetS patients compared to controls, p < 0.001. GABA correlates significantly with cardio-metabolic (CM) features including WC, blood pressure systolic (BP-S) while NAT correlated inversely with WC, BP-S, blood glucose (BG) and triglycerides (TG). GABA correlated positively with chemerin, leptin, Fetuin A and endotoxin. NAT correlated inversely with WC, BP-S, BG, TG, high sensitivity C - reactive protein (hsCRP), toll-like receptor-4 (TLR-4), lipopolysaccharide binding protein (LBP), chemerin and retinol binding protein-4 (RBP-4). ConclusionsWe make the novel observation of increased GABA and PGA with decreased NAT in patients with MetS. While GABA and PGA correlates positively with CM features and biomediators of inflammation, the metabolite NAT correlated inversely. Thus, GABA and PGA could contribute to the pro-inflammatory state of MetS while NAT could mitigate this pro-inflammatory response.

Exploratory lipidomics in patients with nascent Metabolic Syndrome

BackgroundMetabolic Syndrome (MetS) is a cardio-metabolic cluster that confers an increased risk of developing both diabetes and atherosclerotic cardiovascular disease (ASCVD). The mechanisms governing the increased ASCVD risk remains to be elucidated. Moreover, lipidomics poses as an exciting new tool that has potential to shed more light on the pathogenesis of MetS. ObjectiveThe aim of this study was to explore the lipidome in an unbiased fashion in patients with nascent MetS uncomplicated by diabetes and CVD. MethodsPatients with nascent MetS (n = 30) without diabetes or ASCVD and controls (n = 20) who participated in the study had normal hepatic and renal function. Early morning urine samples from patients were collected and frozen at −70° until analysis. Lipidomic analyses were undertaken at the National Institute of Health Western Metabolomics Center. ResultsPhosphatidylcholine 34:2, PC (34:2) was significantly increased in patients with MetS compared to controls. PC (34:2) had a significant positive correlation with waist circumference, plasma glucose, free fatty acid, and triglyceride levels. It had a significant positive correlation with pro-inflammatory markers such as plasma hs CRP, IL-1b, and IL-8. Additionally, PC (34:2) significantly correlated positively with Leptin and inversely with adiponectin. Levels of various acyl carnitines and PC34:1 were not significantly altered. ConclusionWe propose that PC (34:2) could emerge as a novel biomarker in MetS that promotes a pro-inflammatory state.

Changes to trimethylamine-N-oxide and its precursors in nascent metabolic syndrome.

Background Metabolic syndrome (MetS), a cardio-metabolic cluster afflicting 35% of American adults, increases cardiovascular disease (CVD) and type-2 diabetes (T2DM) risk. Increased levels of trimethylamine N-oxide (TMAO), a metabolite derived from choline and L-carnitine, correlates with CVD and T2DM. However, the precise role of TMAO and its precursors in MetS remains unclear. We tested the hypothesis that choline, L-carnitine and TMAO in MetS patients without CVD or T2DM would be altered and correlate with inflammatory markers. Materials and methods This was an exploratory study of 30 patients with nascent MetS (without CVD or T2DM) and 20 matched controls. MetS was defined by the Adult Treatment Panel III criteria. TMAO and its precursors were evaluated from each patient's frozen early morning urine samples and quantified using liquid chromatography/mass spectrometry (LC-MS). These amines were correlated with a detailed repertoire of biomarkers of inflammation and adipokines. Results L-carnitine was significantly increased (p = 0.0002) compared to controls. There was a trend for a significant increase in TMAO levels (p = 0.08). Choline was not significantly altered in MetS. L-carnitine correlated significantly with soluble tumor necrosis factor 1 (sTNFR1) and leptin, and inversely to adiponectin. TMAO correlated with IL-6, endotoxin and chemerin. Neither choline, nor L-carnitine significantly correlated with TMAO. Conclusion L-carnitine is directly correlated with markers of inflammation in nascent MetS. Cellular L-carnitine could be a biomediator or marker of inflammation in the pathogenesis of MetS, and the sequelae of CVD and T2DM.

Amino acid levels in nascent metabolic syndrome: A contributor to the pro-inflammatory burden

AimsMetabolic Syndrome (MetS) is a cluster of cardio-metabolic risk factors characterized by low-grade inflammation which confers an increased risk for type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD). Prior studies have linked elevated branched chain amino acids (BCAA) and aromatic amino acids (AAA) with T2DM and CVD. Due to the paucity of data in MetS, the aim of this study was to investigate the status of amino acids as early biomarkers of nascent MetS patients without T2DM and CVD or smoking. Research design and methodsHealthy controls (n = 20) and MetS (n = 29) patients were recruited for the study. MetS was defined by criteria of National Cholesterol Education Program Adult Treatment Panel III of having at least 3 risk factors. Urinary amino acids were quantified by gas chromatography time-of-flight mass spectrometry at the Western NIH Metabolomics Center as expressed to urinary creatinine. ResultsTyrosine and Isoleucine levels were significantly elevated in MetS patients. Isoleucine positively correlated with salient cardio-metabolic features and inflammatory biomarkers. Lysine and Methionine levels were decreased in MetS patients. Lysine correlated negatively with cardio-metabolic features and inflammatory bimarkers. Methionine also correlated negatively with blood pressure and certain inflammatory biomarkers. ConclusionOur novel results suggest that with regards to the cardio-metabolic risk factors and pro-inflammatory features of MetS, isoleucine (BCAA) demonstrated a positive correlation while lysine demonstrated a negative correlation. Thus, increased levels of isoleucine and decreased levels of lysine could be potential early biomarkers of MetS.

The effect of increasing tertiles of waist circumference on cardio-metabolic risk, adipokines and biomarkers of inflammation and oxidative stress in nascent metabolic syndrome

AimsThe effect of waist circumference (WC) on cardio-metabolic features and biomarkers of oxidative stress and inflammation and adipose tissue dysregulation is poorly defined in Metabolic Syndrome (MetS). Hence the aim of this study was to examine the effect of increasing tertiles of WC on the cardio metabolic risk profile, pro-oxidant state, pro-inflammatory state and adipose tissue dysregulation in nascent MetS patients (n = 59) without diabetes or CVD. Methods and resultsNone of the main cardio-metabolic features including blood pressure, blood glucose, HDL-cholesterol, triglycerides, HOMA-IR, and free fatty acids increased with increasing WC tertiles except for hsCRP. In addition, none of the biomarkers of oxidative stress increased with increasing WC. Other circulating and cellular bio-mediators of inflammation and adipokines did not show significant increase with increasing WC. Using the waist to height ratio (WHtR) also did not reveal any major findings with increasing tertiles. ConclusionIn conclusion, in a well-defined cohort of MetS we failed to show any superiority of either WC or WHtR compared to BMI in capturing the cardio-metabolic cluster, adipose tissue dysregulation and the increased burden of oxidative stress and inflammation in this pilot study. These observations need confirmation in larger studies.

The effect of increasing body mass index on cardio-metabolic risk and biomarkers of oxidative stress and inflammation in nascent metabolic syndrome

The effect of BMI defined obesity on cardio-metabolic features and biomarkers of oxidative stress and inflammation in patients with nascent metabolic Syndrome (MetS) is poorly defined. Hence the aim of this study was to examine the effect of increasing obesity on the cardio metabolic risk profile, pro-oxidant state and pro-inflammatory features in nascent MetS patients without Diabetes or CVD. MetS was diagnosed by ATPIII criteria using waist circumference (WC) as the measure of adiposity. Patients (n=58) were stratified into overweight, obese and extreme obesity groups using BMI cut offs of 25–29.9, 30–39.9kg/m2 and ≥40kg/m2 and cardio-metabolic features, circulating and cellular biomarkers of oxidative stress and inflammation were determined and correlated with BMI. None of the main cardio-metabolic features including blood pressure, blood glucose, HDL-cholesterol, triglycerides, HOMA-IR, free fatty acids were increased with increasing BMI. Also none of the biomarkers of oxidative stress (ox-LDL, nitrotyrosine and monocyte superoxide anion release) were increased with increasing BMI. However, significant increase in hsCRP, the soluble TNFR1 and sTNFR2 and leptin, were observed with increasing adiposity. Other inflammatory bio-mediators (IL-1β, IL-6, IL-8, MCP-1, Toll-like receptors 2–4), endotoxin, LBP, sCD14 and HMGB1, adiponectin, and chemerin did not show significant increases with increasing BMI. Leptin, hsCRP, sTNFR1, and sTNFR2 correlated significantly with BMI. In conclusion, capturing the cardio-metabolic cluster of MetS that predisposed to both increased risk of diabetes and CVD, using waist circumference, as one of the 5 diagnostic criteria is sufficient and BMI does not appear to afford any major incremental benefit on the cardio-metabolic risk factors, increased oxidative stress and the majority of both cellular and circulating biomarkers of inflammation.

Increased fibrosis and angiogenesis in subcutaneous gluteal adipose tissue in nascent metabolic syndrome

AimsMetabolic syndrome (MetS) is globally a common disorder that predisposes to both diabetes and cardiovascular disease (CVD). There is a paucity of data on fibrosis and angiogenesis in adipose tissue (AT) in patients with nascent MetS uncomplicated by diabetes or CVD. Hence, we assayed various indices of fibrosis and angiogenesis in subcutaneous AT (SAT). MethodsIn both patients with MetS and matched controls, we determined fibrosis and the densities of CD31, VEGF and Angiopoietin (Angio) 2 and 1 by immunohistochemistry in gluteal SAT. ResultsThe fibrosis score was significantly increased in SAT of Met S. Also, both CD31 and VEGF densities were significantly increased. Surprisingly, Angio-2 was not increased and the ratio of Angio2:1 was decreased. Both indices of fibrosis and angiogenesis correlated with biomediators of inflammation. ConclusionsIn conclusion, we report increased fibrosis and paradoxical increased angiogenesis in gluteal SAT and speculate that the increased angiogenesis is a protective mechanism in mitigating further adipose tissue dysregulation in this depot.