Circulating Omentin-1 Levels Research Articles

Association between Circulating Omentin-1 Levels and Aortic Valve Sclerosis.

Aortic valve sclerosis (AVS) is characterized by thickening of the valve leaflets accompanied by increased echogenicity and calcification without significant limitations in valve movements. Omentin-1 is a glycoprotein of the adiponectin family released from visceral adipose tissue, and it can be used as a biomarker of atherosclerosis, obesity, and metabolic syndrome. No studies have demonstrated any relationship between AVS and omentin-1 in the literature. We aimed to explore the association of serum omentin-1 levels with AVS. Eighty-six patients with AVS and 92 age- and sex-matched controls were enrolled into the study. The baseline clinical characteristics of the patients were recorded. Conventional 2-dimensional echocardiography was performed. Omentin-1 levels were measured. The mean omentin-1 level was significantly lower in the AVS (+) group compared to the control group (78.16 ± 44.95 vs. 163.57 ± 59.84 ng/mL, p < 0.001). Omentin-1 [odds ratio (OR) = 3.45, 95% confidence interval (CI) = 1.88-5.39, p < 0.001,] and LDL-C (OR = 1.82, 95% CI = 1.33-2.16, p = 0.015) were found to be independent predictors of AVS in multivariate logistic regression analysis. An omentin-1 level of < 92.45 ng/mL had 90.5% sensitivity and 71.4% specificity for the prediction of AVS (area under curve: 0.697, p < 0.001). Our results indicated that a lower omentin-1 level was associated with an increased risk of AVS. We suggest that omentin-1 could be used as a treatment target as well as to predict AVS.

MO732: Circulating Omentin-1 and Subclinical Atherosclerosis in Chronic Haemodialysis Patients: A Pilot Study

Abstract BACKGROUND AND AIMS Chronic haemodialysis (HD) patients are notoriously at high risk for cardiovascular mortality and morbidity. Omentin-1 (OME-1) is an adipocytokine produced by adipose tissue, whose levels are altered in various dysmetabolic conditions, such as obesity and type 2 diabetes mellitus. Beyond this, nowadays there is evidence indicating that this cytokine plays a crucial role in the genesis and progression of systemic atherosclerosis since it may inhibit plaque formation. With this background in mind, we run a pilot investigation to evaluate the possible correlation between circulating OME-1 levels and mean intimal thickness (IMT) in a small, homogeneous cohort of patients treated by HD (‘HD patients’). METHOD From a source cohort of 45 HD patients, we selected 27 individuals suitable to be enrolled. These patients had a dialysis vintage &amp;gt; 6 mo., were on a regular 4 h/3 times week HD regimen and had stable clinical conditions. OME-1 levels were measured in their blood by the ELISA together with common laboratory and clinical parameters before starting a mid-week HD session. All the patients then underwent carotid Doppler ultrasound for IMT measurement. A total of 18 healthy subjects were the controls. RESULTS In the whole cohort, mean IMT values were 0.75 ± 0.12 mm. However, 8/27 patients (29.6%) presented a pathological IMT (&amp;gt;1 mm). Circulating OME-1 levels in the whole HD cohort were increased as compared with controls [763 (367–1423) versus 371 (228–868) ng/mL; P = 0.03]. However, HD patients with pathological IMT presented, on average, lower OME-1 levels as compared with others [483.25 (168.7–1743) versus 1155 (286–2324); P = 0.05]. In ROC analyses, OME-1 values ≤ 840 ng/mL held an 83.3 sensitivity and 66.7 specificity (AUC 0.716, 95% confidence interval 0.506–0.946) in identifying HD patients with pathological carotid thickening. CONCLUSION OME-1 may play a direct role in the atherosclerosis process also in HD patients. Further studies on larger and more heterogeneous HD cohorts are needed to confirm the usefulness of OME-1 plasma levels as potential biomarkers for diagnosing subclinical atherosclerosis and for stratifying the risk of atherosclerosis progression in high-CV risk in HD patients.

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...

Circulating Omentin-1 levels and altered iron balance in chronic haemodialysis patients.

ABSTRACTBackgroundIron deficiency is highly prevalent among patients undergoing chronic haemodialysis (HD) but its correct identification is often problematic as common biomarkers of iron status, such as transferrin saturation (TSAT) and ferritin, can be altered by inflammation or malnutrition.MethodsIn this pilot multicentre study, we aimed at evaluating circulating levels of Omentin-1, a novel fat depot-specific adipokine that is also involved in iron regulation, in a cohort of 85 chronic HD patients with relation to their iron status.ResultsOmentin-1 levels in HD were statistically higher than in healthy controls (P = 0.03) and there was a significant, growing trend in all iron parameters across Omentin-1 tertiles (P < 0.001). Compared with patients with optimal iron status, Omentin-1 levels were lower in subjects categorized according to TSAT ≤20% or serum ferritin ≤200 μg/L (both P < 0.001) and even more reduced in 19 patients (22%) simultaneously displaying low levels of both markers (P < 0.001). In this latter group, Omentin-1 levels increased in parallel to all other iron markers after iron correction by i.v. supplementation. At multivariate regression analyses, ferritin (β = 0.71; P < 0.001) and TSAT (β = 0.32; P = 0.03) remained the sole independent predictors of Omentin-1 levels. This biomarker also showed a remarkable diagnostic capacity at receiver operating characteristic analyses in identifying iron-depleted HD patients according to a criterion of TSAT ≤20% [area under the curve (AUC) 0.827], ferritin ≤200 μg/L (AUC 0.863) or low levels of both parameters (AUC 0.907).ConclusionsFindings obtained indicate that Omentin-1 is somewhat involved in iron balance regulation and might be a candidate biomarker for diagnosing and managing altered iron conditions in HD patients.

Association of Circulating Omentin-1 with Osteoporosis in a Chinese Type 2 Diabetic Population.

Aims Omentin-1, a newly identified adipokine, has been demonstrated to be associated with bone metabolism, but the results have been inconsistent. Moreover, the potential relationship of circulating omentin-1 with diabetic osteoporosis has never been reported. This study is intended for studying the association between circulating omentin-1, bone mineral density (BMD), prior fragility fractures, and other bone metabolic-related parameters. Methods Circulating omentin-1 levels were measured in 172 patients with type 2 diabetes mellitus (T2DM), and participants were divided into the normal BMD group (n = 52), the osteopenia group (n = 66), and the osteoporosis group (n = 54). The relationship between circulating omentin-1 and diabetic osteoporosis and other parameters was analyzed. Results Circulating omentin-1 was significantly higher in the osteoporosis group than in the normal group and in the osteopenia group (both P < 0.05). Circulating omentin-1 levels were correlated significantly and positively with sex; high-density lipoprotein cholesterol; apolipoprotein A; and prevalence of prior fragility fractures, diabetic nephropathy, and retinopathy; they were correlated negatively with diastolic blood pressure, triglyceride, hemoglobin, atherogenic index of plasma, osteoporosis self-assessment tool for Asians, BMD at different skeletal sites, and corresponding T scores, irrespective of age, sex, and body mass index (P < 0.01 or P < 0.05). Moreover, circulating omentin-1 was an independent decisive factor for the presence of osteoporosis only in women after multivariate adjustment (odds ratio: 1.069; 95% confidence interval: 1.003-1.139; P < 0.05). Lastly, the analysis of receiver operating characteristic curves revealed that the best cutoff value for circulating omentin-1 to predict diabetic osteoporosis was 15.37 ng/mL (sensitivity: 71.7%; specificity: 58.5%) in female subjects. Conclusions High levels of circulating omentin-1 may be associated with the development of osteoporosis in female diabetic subjects and may be a potential biomarker for diabetic osteoporosis in women.

Serum omentin-1 levels in hypertensive patients.

Hypertension (HT) is a disease that can cause death due to multiple target organ damage and eventually related vascular system damage. High blood pressure is known increased inflammatory activity and to cause endothelial dysfunction has been showed in HT patients. Omentin-1 is a glucoprotein of the adiponectin family released from visceral adipose tissue, endothelial cells, and visceral fat stromal-vascular cells. It has anti-inflammatory effect and circulating omentin-1 concentration correlates negatively with waist circumference, insulin resistance, and body-mass index. Serum omentin-1 is used as a biomarker of coronary artery disease, obesity, cancer, metabolic syndrome, inflammatorydisease, atherosclerosis, and diabetes mellitus. The aim of our study is to investigate circulating omentin-1 levels in HT patients compared to healthy normotensive controls. Patients diagnosed with new essential HT (n = 61) and healthy normotensive individuals (n = 60) were enrolled in this study. The HT group was separated into two subgroups. There were 30 patients in stage 2 HT group and 31 patients in stage 1 HT group. Omentin-1 levels were significantly lower both in stage 1 and 2 HT subgroup as compared with the normotensive controls (72.19 ± 54.33 ng/ml for stage 1 HT subgroup; 62.45 ± 47.01 ng/ml for stage 2 HT subgroup; and, 147.84 ± 58.55 ng/ml for healthy normotensive controls; overall P < 0.001). The present study demonstrated that serum Omentin-1 levels decreased in patients with HT compared with normotensive controls. These lower concentrations may be attributed to a combined outcome of endothelial dysfunction, renal injury, and inflammation in the setting of hypertension.

Association between Omentin-1 and Coronary Artery Disease: Pathogenesis and Clinical Research.

Like other adipokines, omentin-1 is secreted from visceral adipose tissue and plays a vital role in the development of chronic inflammatory diseases, including cardiovascular events. Recent studies have shown that circulating omentin-1 levels are associated with various metabolic risk factors, such as high blood pressure, increased waist circumference, dyslipidemia, and glucose intolerance. The decrease in serum omentin level is an independent predictor of Coronary Artery Disease (CAD) and is associated with the severity of this disease. Since there is no relevant review in the literature, we aimed to summarize the studies on the relationship between omentin-1 and CAD.

Circulating omentin-1 levels and inflammation in polycystic ovary syndrome.

The aim of the study was to analyze interrelation between plasma omentin-1 levels and nutritional status and inflammation in PCOS. A cross-sectional study involving 86 PCOS (47 obese) and 72 Non-PCOS women (41 obese) determined anthropometric parameters and body composition. Serum glucose, insulin and omentin-1, TNF-α, sTNFRs, IL-6 and sR-IL6 were measured in the fasting state. Plasma omentin-1 levels were significantly lower in the PCOS than in the Non-PCOS group and both corresponding normal weight and obese subgroups. In three analyzed least-angle regression (LARS) models the lower plasma omentin- 1 levels was associated with PCOS occurrence, higher circulating TNF-α and lower IL-6 levels. Suppressed omentin-1 levels in PCOS are characteristic for this disturbance and proinflammatory cytokines are factors modifying secretion of this adipokine.

MON-691 Association of Serum Level of Omentin-1, Hs-CRP and Atherosclerosis in Patients with Type 2 Diabetes

Omentin-1 has been identified as an interesting novel adipokine that may modulate the action of insulin. Serum omentin-1 levels were associated with endothelial dysfunction and cardiovascular diseases, which highly contribute to morbidity and mortality of patients with diabetes, however its exact biological function is still unclear. The aim of this study was to assess the level of circulating plasma Omentin-1 level in patients with type 2 diabetes compared to control subjects, and to investigate the relationship of circulating Omentin-1levels with HOMA, BMI, lipid profile, epicardial fat, visceral fat and subcutaneous fat in early stages of atherosclerosis measured by carotid intima media thickness (CIMT). This is a cross-sectional observational study which included 45 patients with type 2 DM (not previously diagnosed as ACVD patients) and 30 (age and sex)-matched healthy control subjects. Patients with a history of recent acute infection, malignancy, metabolic or endocrinal diseases, cardiac failure, renal and hepatic impairment were excluded. Participants were subjected to measurement of FPG, HbA1c, lipid profile, calculation of HOMA2, hs CRP, serum omentin-1, CIMT, estimation of visceral, epicardial and subcutaneous fat through CAT scanning. There was no statistically significant difference between both groups in the mean circulating omentin-1 level, a mean of (793.86 ± 195.81) ng/ml in type 2 diabetes Vs (804.93 ± 205.76) ng/ml in the control group,(p=0.654). However, there was a highly statistically significant difference in hs-CRP between both groups, mean hs CRP is (4.29 ± 4.87 mg/l) vs (0.92 ± 0.53 mg/l) respectively. There was a statistically significant negative correlation between omentin-1 and hs CRP (r= -0.278, p= 0.016).There were no statistically significant correlations between omentin-1 with BMI, HbA1c, HOMA, lipid profile or adiposity. These findings may denote the anti-inflammatory effects of omentin-1 which maybe unrelated to insulin resistance and dyslipidemia. Further studies are required to confirm the cardioprotective role of omentin-1 in patients with type 2 diabetes, focusing on its local anti-inflammatory role.Nothing to disclose: MA, NA, NKNo Sources of Research Support

Circulating adipokines are associated with Kawasaki disease

BackgroundThe pathogenesis of Kawasaki disease are still not well understood. It was designed to investigate the relationship between adipokines including chemerin, omentin-1, adiponectin and acute Kawasaki disease.MethodsEnzyme-linked immunosorbent (ELISA) was used to detect serum levels of chemerin, omentin-1, adiponectin, and inflammatory cytokines IL-1β and TNF-α in 80 cases of patients diagnosed with Kawasaki disease (KD). In addition, 20 cases of children with fever and 20 cases of healthy children were selected as febrile and normal controls.Results(1) Serum levels of chemerin in KD group (87.736 ± 56.310) are higher than that of both the healthy (41.746 ± 10.824) and the febrile controls (59.683 ± 18.282) (P < 0.01). (2) Circulating omentin-1 levels in Kawasaki disease group (389.773 ± 238.611) are significantly lower than that of febrile control (542.075 ± 177.995) (P < 0.01), also serum adiponectin levels in Kawasaki disease group (16.400 ± 12.243) reduced obviously compared with the febrile control group (35.074 ± 12.486). (3)Serum cytokine levels of IL-1β in Kawasaki disease group (13.656 ± 31.151) are higher than those of normal controls (2.415 ± 6.313) (P < 0.05). (4) Correlation analysis indicates that serum levels of chemerin are positively correlated with omentin-1 (r = 0.224, 95% CI 0.06–0.529, P < 0.05). Further, serum omentin-1 levels and total cholesterol (TC) are positively correlated (r = 0.358, 95% CI 0.169–0.518, P < 0.01).ConclusionsCirculating chemerin increased significantly in the acute stage of Kawasaki disease, while omentin-1 and adiponectin levels are decreased. These adipokines are closely associated with the early inflammation and lipid metabolism disorders of acute Kawasaki disease.

Serum levels of omentin-1 are increased after weight loss andareparticularly associated with increases in obese children withmetabolicsyndrome.

There have been very few paediatric studies on omentin-1, an anti-inflammatory adipokine that provides a link between adiposity, insulin resistance and metabolic syndrome. This Chinese study evaluated the association between omentin-1 and metabolic syndrome and analysed the effect of a six-month lifestyle intervention on the levels in obese children. We recruited 119 obese outpatients (75% boys) aged 7-18years from the Second Affiliated Hospital of Xi'an Jiaotong University, who underwent a six- month lifestyle intervention. Our controls were 55 matched children with normal weight. Anthropometric parameters, biochemical data and circulating omentin-1 levels were measured at baseline and after six months. Of the 119 obese children, 32 (27%) had metabolic syndrome. The obese children, particularly those with metabolic syndrome, had significantly lower serum omentin-1 levels at baseline than the controls. We also found that the omentin-1 levels were negatively associated with their body mass index, waist circumference and homoeostasis model assessment of insulin resistance. After the six-month lifestyle intervention, the obese children showed significant weight loss and their omentin-1 levels increased. Serum omentin-1 was regulated by weight and seemed to be associated with children's metabolic disorders. A six-month lifestyle intervention significantly increased serum omentin-1 levels.

Adipose Tissue-Derived Omentin-1 Function and Regulation.

Omentin-1, also known as intelectin-1, is a recently identified novel adipocytokine of 313 amino acids, which is expressed in visceral (omental and epicardial) fat as well as mesothelial cells, vascular cells, airway goblet cells, small intestine, colon, ovary, and plasma. The level of omentin-1 expression in (pre)adipocytes is decreased by glucose/insulin and stimulated by fibroblast growth factor-21 and dexamethasone. Several lines of experimental evidence have shown that omentin-1 plays crucial roles in the maintenance of body metabolism and insulin sensitivity, and has anti-inflammatory, anti-atherosclerotic, and cardiovascular protective effects via AMP-activated protein kinase/Akt/nuclear factor-κB/mitogen-activated protein kinase (ERK, JNK, and p38) signaling. Clinical studies have indicated the usage of circulating omentin-1 as a biomarker of obesity, metabolic disorders including insulin resistance, diabetes, and metabolic syndrome, and atherosclerotic cardiovascular diseases. It is also possible to use circulating omentin-1 as a biomarker of bone metabolism, inflammatory diseases, cancers, sleep apnea syndrome, preeclampsia, and polycystic ovary syndrome. Decreased omentin-1 levels are generally associated with these diseases. However, omentin-1 increases to counteract the acute phase after onset of these diseases. These findings indicate that omentin-1 may be a negative risk factor for these diseases, and also act as an acute-phase reactant by its anti-inflammatory and atheroprotective effects. Therapeutic strategies to restore omentin-1 levels may be valuable for the prevention or treatment of these diseases. Weight loss, olive oil-rich diet, aerobic training, and treatment with atorvastatin and antidiabetic drugs (metformin, pioglitazone, and exenatide) are effective means of increasing circulating omentin-1 levels. This review provides insights into the potential use of omentin-1 as a biomarker and therapeutic target for these diseases. © 2017 American Physiological Society. Compr Physiol 7:765-781, 2017.

Circulating omentin-1 levels in women with polycystic ovary syndrome: a meta-analysis

To investigate the association between circulating omentin-1 levels and polycystic ovary syndrome (PCOS) in women, a meta-analysis was performed. A systematic literature search using PubMed, Embase and Web of Science was carried out. Ten articles with 13 studies were included in this meta-analysis, which included a total of 1264 subjects (733 patients with PCOS and 531 controls). The pooled standard mean difference (SMD) and 95% confidence interval (CI) were used to estimate the association between omentin-1 levels and PCOS. Circulating omentin-1 levels were lower in PCOS with an SMD (95% CI) of −0.67 (−0.91, −0.43) and p = 0.000 (random-effects). However, significant heterogeneity was detected across studies (I2=73.6% and p = 0.000). The subgroup analysis suggested that omentin-1 levels in PCOS patients were associated with HOMA-IR ratio. Meta-regression analysis indicated region was the main source of heterogeneity (p = 0.048). The results of this meta-analysis suggested that circulating omentin-1 levels are significantly lower in women with PCOS compared with controls, which indicated that omentin-1 may play a role in the pathologic processes of PCOS.

Circulating omentin-1 levels and its association with insulin resistance in newly diagnosed impaired glucose tolerant subjects

Circulating omentin-1 levels and its association with insulin resistance in newly diagnosed impaired glucose tolerant subjects

Circulating levels of adipocytokine omentin-1 in patients with renal cell cancer

Renal cell carcinoma (RCC) is the fifth most common cancer worldwide, and becomes one of the leading causes of genitourinary cancer-related death in both males and females. Genetic alternations, alcohol consumption, occupationally harmful exposure and even obesity are well-established risk factors of RCC. Omentin-1 is a plasma adipokine synthesized in visceral adipose tissue, and its circulating serum concentration alters not only in conditions associated with insulin resistance such as Polycystic Ovary Syndrome (PCOS), but also in colorectal cancer and prostate cancer. To our best knowledge, the relationship between omentin-1 and RCC has not been clarified previously. Thus, we evaluated serum omentin-1 levels in RCC patients in the current matched case-control study. Forty-one patients newly diagnosed with RCC and forty-two healthy controls confirmed by the comprehensive medical examination were assessed. The omentin-1 concentrations were determined via utilizing enzyme-linked immunosorbent assays (ELISA) in the paired groups, in which the patients and healthy controls had no statistically significant differences in gender, age, systolic blood pressure (SBP), diastolic blood pressure (DBP), waist-hip ratio (WHR), estimate glomerular filtration rate (eGFR), body-mass index (BMI) and biochemical parameters. The omentin-1 levels in healthy people were 9.86±1.44ng/mL and the circulating omentin-1 levels were dramatically decreased to 3.62±0.76ng/mL in RCC patients (p<0.001). Besides, we revealed a negative correlation between omentin-1 with WHR (r=−0.261, p=0.017) and BMI (r=−0.310, p=0.004), further indicating BMI was the main influential factor on omentin-1 levels (p=0.0091). Follow-up studies would be conducted to establish the concrete mechanisms underlying the altered circulating levels of omentin-1 and elucidate the interaction between “RCC complex system” and adipose tissues, which may together provide promising and novel pharmacological insights for RCC theragnosis in the near future.

Plasma Omentin-1 Levels are Related to Exercise Performance in Obese Women and Increase Upon Aerobic Endurance Training

Omentin-1 is an adipokine that is primarily released from visceral adipose tissue stromal cells. The effects of exercise on omentin-1 regulation are not clear so far. Therefore, the effect of endurance training on circulating omentin-1 levels and its relation to exercise performance was assessed in obese women. 13 obese women (age: 44.8±3.3 years; BMI: 37.8±1.3 kg·m(-2)) participated in a 6-week endurance training program. Omentin-1, metabolic traits (glucose, insulin, HOMA-IR, lipids profile), and exercise performance (cardiopulmonary exercise test (V̇O2,peak, Wpeak), 6 min walking test, 6MWT) were assessed before and after the training. After the training program circulating omentin-1 were 10.4% higher than before the program (690±50 ng·ml(-1) vs. 618±42; p=0.04), while body weight remained unchanged (p=0.9). Before training, omentin-1 levels were significantly correlated with Wpeak (given in absolute and relative values) as well as with 6MWT (all r≥0.603; all p≤0.029) and the correlations with absolute as well as relativeV̇O2,peak approached significance (both r≥0.534; both p≤0.060). After training, respective correlations were generally weaker and did not reach significance any longer (all r≤0.465; all p≥0.109). Neither before nor after the training program were significant correlations found between omentin-1 levels and the other measured metabolic blood markers (all p≥0.157). Data show a rather strong relationship between exercise performance and circulating omentin-1 levels as well as an increase of the adipokine in response to 6-week of endurance training in obese women. Our findings may hint to a skeletal muscle-adipose tissue crosstalk in regard of omentin-1 regulation.

Omentin-1 levels are reduced by pharmacologic doses of leptin, but remain unaffected by energy deprivation and display no day-night variation.

ObjectiveTo study the day-night variation of omentin-1 levels and assess whether leptin, and/or short-and long-term energy deprivation alter circulating omentin-1 levels via cytokines.Design and MethodsOmentin-1 levels were measured hourly in serum samples from six healthy men to evaluate for day-night variation. To study effects of acute energy deprivation and of leptin administration, eight healthy subjects were studied in the fasting state for 72 hours with administration of either placebo or metreleptin in physiological replacement doses. We evaluated the effect of leptin in pharmacological doses on serum omentin-1 and cytokine levels, as well as on omentin-1 levels in ex vivo omental adipose tissue, in fifteen healthy volunteers. To study the effect of chronic energy deprivation and weight loss on omentin-1 levels we followed eighteen obese subjects for 12 months who underwent bariatric surgery.ResultsThere is no day-night variation in omentin-1 levels. Short-term and chronic energy deprivation as well as ex vivo leptin administration and physiological replacement doses of leptin do not alter omentin-1 levels, whereas pharmacologic doses of metreleptin reduce omentin-1 levels whereas levels of TNF-α receptor II and IL-6 tend to increase.ConclusionsOmentin-1 levels are reduced by pharmacological doses of metreleptin independent of effects on cytokine levels.

Evaluation of the relationship between circulating omentin-1 concentrations and components of the metabolic syndrome in adults without type 2 diabetes or cardiovascular disease

BackgroundDysregulation of omentin-1, a beneficial adipokine, is thought to play a role in the development of type 2 diabetes and cardiovascular disease. The objective of this study was to evaluate the relationship between circulating omentin-1 concentrations and components of the metabolic syndrome in adults without type 2 diabetes or cardiovascular disease, and to determine if sex differences influenced the observed relationships.MethodsFasting blood samples were obtained from 93 adults, ages 30–60 years, without type 2 diabetes and/or cardiovascular disease. Participants were classified as having the metabolic syndrome according to American Heart Association/National Heart, Lung and Blood Institute criteria. Plasma omentin-1 concentrations were measured using a commercially-available enzyme-linked immunosorbent assay, and relationships between plasma omentin-1 and components of the metabolic syndrome were assessed in the entire study cohort, by metabolic syndrome status, and by sex.ResultsOn average, participants were 48 ± 8 years of age, 50.5% were women, 54.8% were Caucasian, and 70% had the metabolic syndrome. Plasma omentin-1 concentrations did not differ significantly between individuals with versus without the metabolic syndrome (145.7 ± 70 versus 157.4 ± 79.3 ng/ml, p = 0.50). However, men with the metabolic syndrome had significantly lower omentin-1 levels than men without the metabolic syndrome (129.9 ± 66 versus 186.3 ± 84.3 ng/ml, p = 0.03). Plasma omentin-1 concentrations were significantly correlated with HDL cholesterol in the entire study cohort (r = 0.26; p = 0.01), which was primarily driven by a correlation in men (r = 0.451, p = 0.002) and participants with the metabolic syndrome (r = 0.36; p = 0.003). Plasma omentin-1 concentrations did not differ significantly between men and women; however men with the metabolic syndrome had 20% lower plasma omentin-1 levels than women with the metabolic syndrome (p = 0.06).ConclusionThese data demonstrate that circulating omentin-1 levels are associated with HDL cholesterol, primarily in men and in the presence of the metabolic syndrome. In addition, sex appears to influence the relationship between plasma omentin-1 concentrations and components of the metabolic syndrome. Additional studies are needed to explore sexual dimorphism in circulating omentin-1 levels, and the role of omentin-1 in the metabolic syndrome.

Cardioprotective Properties of Omentin-1 in Type 2 Diabetes: Evidence from Clinical and In Vitro Studies

ContextAdipokines are linked to the development of cardiovascular dysfunction in type 2 diabetes (DM2). In DM2-patients, circulating levels of omentin-1, an adipokine preferentially expressed in epicardial adipose tissue, are decreased. This study investigated whether omentin-1 has a cardioprotective function.MethodsOmentin-1 levels in plasma and cardiac fat depots were determined in DM2-patients versus controls. Moreover, the relation between omentin-1 levels and cardiac function was examined in men with uncomplicated DM2. Finally, we determined whether omentin-1 could reverse the induction of cardiomyocyte dysfunction by conditioned media derived from epicardial adipose tissue from patients with DM2.ResultsOmentin-1 was highly expressed and secreted by epicardial adipose tissue, and reduced in DM2. Circulating omentin-1 levels were lower in DM2 versus controls, and positively correlated with the diastolic parameters early peak filling rate, early deceleration peak and early deceleration mean (all P<0.05). The improved diastolic function following pioglitazone treatment associated with increases in omentin-1 levels (P<0.05). In vitro, exposure of cardiomyocytes to conditioned media derived from epicardial adipose tissue from patients with DM2 induced contractile dysfunction and insulin resistance, which was prevented by the addition of recombinant omentin.ConclusionThese data identify omentin-1 as a cardioprotective adipokine, and indicate that decreases in omentin-1 levels could contribute to the induction of cardiovascular dysfunction in DM2.

Implication of circulating omentin-1 level on the arterial stiffening in type 2 diabetes mellitus

Omentin-1 is an adipokine implicated in diabetes, inflammation, and cardiovascular disease. However, no prospective studies have examined the impact of circulating omentin-1 levels on arterial stiffening in patients with type 2 diabetes mellitus. For the purpose of this study, we recruited 120 patients with type 2 diabetes mellitus and measured serum omentin-1, adiponectin, and high-sensitivity C-reactive protein levels as well as other cardiovascular risk factors. Arterial stiffness was assessed by brachial ankle pulse wave velocity (baPWV). An increase in the level of circulating omentin-1 over a period of 1 year was positively correlated with changes in levels of HbA1c and serum adiponectin as well as baPWV. Subjects with higher baseline serum omentin-1 levels tended to have a reduced arterial stiffness after 1 year (P for linear trend = 0.03). In the group with increased baPWV after 1 year, the magnitude of increase of circulating omentin-1 levels was significantly higher than in the group with a lower baPWV after 1 year (134.3 [16.6, 277.1] ng/mL vs. 15.9 [-67.6, 145.7] ng/mL, P < 0.01). Multiple stepwise logistic regression analysis revealed that an increase in systolic blood pressure and an increase in serum omentin-1 level were independently correlated with arterial stiffening, even after adjusting for other cardiovascular risk factors and medication history. Baseline serum omentin-1 levels can predict arterial stiffness changes occurring within a year. Furthermore, changes in serum omentin-1 levels after a year can function as independent markers of arterial stiffening in patients with type 2 diabetes mellitus.