Serum Apelin Research Articles

Serum Apelin 13 Levels in Patients With Pulmonary Embolism.

Expression and peptide immunoreactivity of apelin messenger RNA have been described in a variety of tissues, including gastrointestinal tract, adipose tissue, brain, kidney, liver, cardiovascular system, and lungs. This study aimed to investigate the possible involvement of the endogenous apelin in the pathophysiological events that occur in patients with pulmonary embolism (PE). In total, 53 patients with PE and 35 healthy volunteers were included the study. This cross-sectional study was conducted at a tertiary care university hospital and among patients diagnosed as having PE. The control group consisted of healthy volunteers who applied to hospital for a routine checkup examination. Serum apelin 13 levels were measured in both the groups and their results were compared. The median ages were 57 and 53 years, and female-male ratios were 30/23 and 20/15, in the PE and control groups, respectively. The mean serum apelin 13 levels were found to be significantly higher in the PE group (76.94 ± 10.70 ng/mL) than in the control group (50.01 ± 7.13 ng/mL; P < .001). This study demonstrated that apelin 13 levels are elevated in patients with PE. These results suggest that apelin may be a novel biomarker and a potential therapeutic target in patients with acute PE in the future.

Assessment of Apelin Serum Levels in Persistent Atrial Fibrillation and Coronary Artery Disease

BackgroundApelin, the endogenous ligand of orphan receptor APJ (gene symbol APLNR), is an adipokine that was suggested to have a direct correlation with obesity. This peptide might play a role in obesity-related disorders, especially in the cardiovascular system. Currently, few data are available on levels and potential metabolic functions of apelin in different cardiac diseases including atrial fibrillation (AF) and coronary artery disease (CAD), which have common underlying pathophysiological mechanisms. This study aimed to investigate apelin levels in patients with AF and CAD that were overweight or obese, as well as its relationship with anthropometry and metabolic profile. MethodsThis preliminary investigation was compromised of 41 patients with AF and 39 with CAD aged > 50 years and body mass index (BMI) > 25kg/m2. Serum levels of apelin, fasting plasma glucose, insulin, homeostatic model assessment, triglyceride, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and very-low-density lipoprotein were measured. ResultsThe apelin serum levels were not statistically different between patients with AF and CAD. A negative correlation was observed between apelin with weight (r = −0.257, P = 0.023) and BMI (r = −0.258, P = 0.023). Moreover, apelin showed an inverse correlation with insulin (r =−0.227, P = 0.045) and marginally with homeostatic model assessment (r = −0.21, P = 0.066). There was a negative association between apelin and triglyceride (r = −0.238, P = 0.036) and very-low-density lipoprotein (r = −0.25, P = 0.027). ConclusionsApelin serum levels were not significantly different among patients with AF and CAD. The unexpected inverse correlation of apelin with weight and BMI might indicate the dominant effects of pathophysiological conditions such as AF and CAD on serum levels of apelin compared with BMI and adipose tissue. Understanding the precise role of apelin in modulating obesity-induced disorders including AF and CAD requires further studies.

Serum apelin is associated with affective disorders in peritoneal dialysis patients

Objective: Depression and anxiety are prevalent affective disorders in peritoneal dialysis (PD) patients. Recent research has proposed a potential role of apelinergic system in pathogenesis of depression. The present study aimed to evaluate the frequency of depression and anxiety and their potential relation with serum apelin levels among PD patients.Methods: A total of 40 PD patients were enrolled into the study. Depressive symptoms and anxiety were assessed with the Beck’s Depression Inventory and the Beck’s Anxiety Inventory. Serum apelin-12 levels were measured by immunoenzymatic assays using commercially available ELISA kit for standard human apelin.Results: Of the patients, 16 (40%) had depression, 20 (50%) had anxiety. The patients with depression and anxiety had a significantly longer time on dialysis (p < 0.001 for both), significantly higher serum apelin (p < 0.001 for both) and C-reactive protein levels (p < 0.001 for both) than those without depression and anxiety. In multivariate analysis, serum apelin was the only parameter associated independently with depression and anxiety scores.Conclusions: A substantial number of PD patients had depression and anxiety. Increased levels of serum apelin may constitute a significant independent predictor of development of depression and anxiety in PD patients.

A study of apelin level in children with chronic kidney disease

Objective The aim of this study was to evaluate serum apelin levels in Egyptian pediatric patients with chronic kidney disease (CKD) and its relation with markers of endothelial dysfunction, cardiac functions, and nutritional status. Patients and methods Our study comprised 66 clinically stable CKD patients and 20 normal healthy volunteers. We performed enzyme-linked immunosorbent assay technique to assess serum levels of apelin and; vascular cell adhesion molecule-1 (VCAM-1). Cardiac functions were assessed by means of echocardiogram. Nutritional analysis was achieved with the 24 h dietary recall method. Results VCAM-1 levels were significantly elevated in children with CKD as compared with controls. No difference in apelin mean levels was found between patients and controls. VCAM-1 levels positively correlated with interventricular septum thickness, and inversely correlated with both vitamin B1 and magnesium intake determined by means of food analysis. Conclusion Children with CKD had endothelial dysfunction that was detected by means of elevated levels of serum VCAM-1, which showed a relation to height and weight of the patients, as well as a relation to interventricular septum thickness and with magnesium and vitamin B1 intake. However, there was no difference in serum apelin levels between the patients and controls and no relation was found with VCAM-1.

Effect of 6 Weeks of High-Intensity Interval Training with Cinnamon Supplementation on Serum Apelin Concentration and Insulin Resistance in Overweight Boys

Effect of 6 Weeks of High-Intensity Interval Training with Cinnamon Supplementation on Serum Apelin Concentration and Insulin Resistance in Overweight Boys

Serum apelin and ADMA levels in type 2 diabetics with and without vascular complications

AimsType 2 diabetes mellitus (T2DM) is a metabolic and chronic disease which is characterized by hyperglycemia, and that is the major causes of various micro and macrovascular complications. Asymmetrical dimethylarginine (ADMA), formed by the hydrolysis of proteins containing methylated arginine residues, is an endogenous inhibitor of nitric oxide synthase (NOS), which oxidize l-arginine to citruline and nitric oxide (NO), related to hyperinsulinaemia and hyperlipidaemia. Apelin is a recently discovered peptide, present in a number of tissues and play role in insulin sensitivity improvement. In this study, our aim was to determine the levels of apelin and ADMA with glycated haemoglobin (HbA1c) in type 2 diabetic patients with or without vascular complications. MethodsThis study included (a total of) 59 diabetic patients. Of the patients, 30 were diabetic with complications, and 29 without complications. In serum samples obtained from the patients, serum ADMA and apelin levels were measured with Enzyme Linked Immunosorbent Assay (ELISA) method. ResultsOur study totally enrolled 59 patients in two groups. No significant differences were found in sex, age, HbA1c and glucose levels among groups. Apelin and ADMA levels of group with complications were lower than those of group without complications, but no statistically significant difference of apelin and ADMA levels (p>0.05). ConclusionThe results of this study have been showed no statistically significant relationship present between ADMA–apelin levels and complications of T2DM. Further studies involving larger patients populations and healthy controls should be done to clarify the pathogenetic significance of apelin and ADMA in diabetic vascular complications.

Clinical Implications of the Serum Apelin Level on Portal Hypertension and Prognosis of Liver Cirrhosis.

Background/AimsLevels of serum apelin (s-apelin), an endogenous ligand for angiotensin-like receptor 1, have been shown to be related to hepatic fibrosis and hemodynamic abnormalities in preclinical studies. We investigated the clinical implications of s-apelin as a noninvasive prognostic biomarker for chronic liver disease (CLD).MethodsFrom January 2009 to December 2012, 215 CLD patients were enrolled and underwent clinical data collection, hepatic venous pressure gradient (HVPG) measurement, and liver biopsy. s-apelin was detected with a human total apelin enzyme-linked immunosorbent assay kit. All patients were prospectively observed during the median follow-up period of 23.0±12.9 months for decompensation and mortality.ResultsA total of 42 patients (19.5%) died during the follow-up period. s-apelin was significantly correlated with measurements of liver stiffness (R2=0.263, p<0.001) and collagen proportional area (R2=0.213, p<0.001) measured from liver biopsy tissue and HVPG (R2=0.356, p<0.001). In a multivariate analysis using a Cox regression hazard model, s-apelin was a weakly significant predictor of decompensation (hazard ratio [HR], 1.002; p<0.001) and mortality (HR, 1.003; p<0.001).Conclusionss-apelin showed a significant relationship with CLD severity. However, its significance as a noninvasive biomarker for disease severity and prognosis was weak.

The effects of prolonged fasting on the levels of adiponectin, leptin, apelin, and omentin in pregnant women

The aim of the present study was to evaluate serum adiponectin, leptin, apelin and omentin levels to explore metabolic changes occurring during fasting in the month of Ramadan. The study was designed as a prospective study. The patients were divided into two groups, each comprising 20 patients: Group I, fasting pregnant women, and Group II, non-fasting pregnant women. The patients’ age, parity, gestational week and body mass index were recorded. Adiponectin and omentin levels were significantly lower in fasting pregnant women (p < 0.001). When the two groups were compared in terms of serum leptin and apelin levels, both were found to be significantly higher in Group I than in Group II. The findings of the present study suggest that pregnant women who are willing to fast during 24–38 weeks’ gestation should be informed about insulin resistance.

Evaluation of Serum Apelin in Acute Coronary Syndrome Patients

Background: Acute coronary syndrome refers to any group of clinical symptoms compatible with acute myocardial ischemia including unstable angina (UA), Non-ST-segment elevation myocardial infarction (NSTEMI) &amp; ST-segment elevation myocardial infarction (STEMI).Apelin is a novel endogenous peptide with inotropic and vasodilatory properties, it was recently reported that serum measurements of apelin were similar to its immunohistochemical data in vessels and heart tissues.Objectives: This study aims to evaluate serum levels of apelin in patients with Acute Coronary Syndrome related to severity of presentation.Patients and Methods: The present study was conducted during the period from September 2014 until March 2015. Fifty-nine patients with ACS were included as (30 UA, 15 NSTEMI, &amp; 14 STEMI) patients. Also the study included (28) apparently healthy persons served as control. Blood samples were obtained for measurements of Apelin by ELISA method.Results: Serum apelin levels were significantly decreased in whole group of patients with ACS (1846.1±320.9) ng/ml compared to control (2719.4±272.5) ng/ml (p&lt; 0.05). Regarding patients’ subgroups; serum apelin was lowest in STEMI (1729.0±480.0) ng/ml, NSTEMI (1816.0±289.0) ng/ml, &amp; UA (1916.0±224.4) ng/ml when compared with control; respectively.Conclusion: Data obtained revealed a reduction in serum apelin levels in all patients groups especially STEMI, so it could be considered as a biochemical marker for evaluation of ACS.

The role of serum apelin in diabetic patients with retinopathy

Objective The aim of this work is to study serum apelin in patients with diabetic retinopathy and its possible pathophysiological role in such patients. Background Diabetic retinopathy is the most common microvascular complication of diabetes, and it remains a leading cause of blindness and visual impairment in the working-age population in the developed world. Apelin is a peptide isolated from bovine stomach extracts that acts as an endogenous ligand for the previously orphaned G protein-coupled receptors (angiotensin 1-related putative receptors). Apelin has been recognized as a factor promoting angiogenesis, but its role in the development of proliferative diabetic retinopathy (PDR) has not been fully examined. Materials and methods Sixty patients were included in the study and classified into three groups. Group 1, the control group, included individuals without diabetes mellitus (10 patients), group 2 included patients with diabetes mellitus but without retinopathy (20 patients), and group 3 included patients classified into two subgroups: group 3a, which included patients with nonproliferative diabetic retinopathy (NPDR) (15 patients), and group 3b, which included patients with PDR (15 patients). Results Apelin was significantly higher among patients with diabetes without retinopathy, NPDR, and PDR than the control group (P Conclusion Serum apelin was significantly higher in patients with PDR compared with those without nonproliferative retinopathy and in those with diabetes without retinopathy, and apelin plays a role in the development of PDR. Ischemic retinopathy could be trated with Inhibition of the apelinergic system. Serum apelin correlated significantly with serum creatinine in patients with retinopathy, which may indicate the role of apelin in diabetic nephropathy.

تقييم الابيلين في مصل الدم لدى مرضى المتلازمة التاجية الحادة

تقييم الابيلين في مصل الدم لدى مرضى المتلازمة التاجية الحادة

Serum apelin as a novel non-invasive marker for subclinical cardiopulmonary complications in children and adolescents with sickle cell disease

BackgroundCardiovascular involvement represents a leading cause of mortality and morbidity in sickle cell disease (SCD). Apelin is a peptide involved in the regulation of cardiovascular function. AimTo determine serum apelin among 40 children and adolescents with SCD compared with 40 healthy controls and assess its relation to markers of hemolysis, iron overload as well as cardiopulmonary complications. MethodsSCD patients, in steady state and asymptomatic for heart disease, were studied stressing on hydroxyurea/chelation therapy, hematological profile, serum ferritin and apelin levels. Full echocardiographic study including assessment of biventricular systolic function and pulmonary artery pressure was done. ResultsApelin levels were significantly lower in SCD patients compared with controls (P<0.001). Cardiopulmonary complications were encountered in 30% of patients. Apelin was significantly decreased among patients with cardiopulmonary disease (P=0.006) whether those at risk of pulmonary hypertension (P=0.018) or patients with heart disease (P=0.043). Hydroxyurea-treated patients had higher apelin levels than untreated ones (P=0.001). Apelin was negatively correlated to lactate dehydrogenase, indirect bilirubin, serum ferritin, end systolic diameter, tricuspid regurgitant jet velocity, right ventricle systolic pressure, pulmonary vascular resistance and tissue Doppler imaging S wave. Apelin cutoff value of 1650ng/L could significantly detect the presence of cardiopulmonary complications in SCD with 90.9% sensitivity and 72.4% specificity. ConclusionApelin is a promising marker for screening of SCD patients at risk of cardiopulmonary disease because it is altered during the early subclinical stage of cardiac affection. A combination of apelin and echocardiography provides a reliable method to assess cardiopulmonary affection in young SCD patients.

Evaluation of adipokines in children with cystic fibrosis.

Patients with CF present numerous pathological conditions such as malnutrition, depletion of fat-free mass, metabolic disturbances (abnormal glucose metabolism, increased insulin resistance, chronic energy deficit, local and chronic inflammation), which could affect or be associated with altered adipokines concentration Material and Methods: We aimed in this study to investigate the levels of selected adipokines such as resistin, apelin, adiponectin to demonstrate their application as possible markers of inflammation. Serum level of resistin was higher (p < 0.001) and adiponectin - lower (p=0.02) in CF children than in healthy children. There was no difference in serum apelin level between two examined groups. However, values of adiponectin/BMI and apelin/BMI ratios in CF did not differ significantly from controls. Higher values of resistin/BMI ratio in CF in comparison to controls were observed Serum resistin/adiponectin ratio was significantly higher in CF patients than in controls (p < 0.0001). Resistin/BMI ratio correlated negatively with FEV1 (R:-48,p < 0.043). Serum resistin/adiponectin ratio correlated negatively with FEV1/FVC (R:-49, p=0.04), Adipokines showed no correlation with BMI and BMI-SDS, glucose, total cholesterol, and LDL-, HDL-cholesterol, triglyceride serum levels. Spirometric parameters FEV1, FVC, VC correlated negatively with serum glucose levels (R: -0.55, p < 0.018; R: -0.65 p < 0.0025; R:-0.76, p < 0.0008 respectively). FEV1 and FVC correlated positively with BMI-SDS (R:0.58, p < 0.01; R:0.5, p < 0.036, respectively). A significant increase in resistin concentration expressed also as resistin/BMI, and resistin/adiponectin ratios, observed in children with CF may suggests that this adipokine is involved in the inflammatory process underlying the disease and is related to worse spirometric parameters describing airways obstruction.

105 - Oxidative Stress Blunts the Vasodilator Effects of Sodium Nitrite Mediated by Xanthine Oxidoreductase in 2K1C Hypertension

Chronic kidney diseases lead to severe cardiovascular consequences such as hypertension and cardiac failure. Apelin, along with its receptor APJ have been shown to involve in cardiovascular functions including blood pressure (BP) lowering effect and also a positive inotropic effect on failing hearts. Therefore we investigated the effect of apelin on BP and cardiac contractility in chronic two-kidney–one-clip (2K1C) hypertension, a kidney disease hypertension model. The changes in the level of apelin and some other hemodynamically effective hormones in serum and apelin receptor gene expression in nonischemic and ischemic kidneys were also assessed.2K1C was produced by placing a Plexiglas clip around the left renal artery. 16 weeks later, BP and cardiac indices of contractility were measured by power lab system. The mRNA and protein level of APJ were determined by RT-PCR and Western blot methods respectively.2K1C increased BP from 115/75 mm Hg in sham to 180/120 mm Hg in test group. Hypertensive rats had about ten times higher basal left ventricular end-diastolic pressure (LVEDP) (P < 0.001) and higher basal LV systolic pressure (LVSP) (P < 0.01). Apelin-13 (20 μg/kg, iv) significantly decreased LVEDP and LVSP (P < 0.001). Furthermore, apelin in 20 μg/kg dose significantly decreased systolic (SBP) and diastolic (DBP) blood pressures in hypertensive rats. This reduction was persistent and prominent in 40 μg/kg dose. 20 μg/kg apelin increased + LVdp/dt max and − LV dp/dt max. However in the dose of 40 μg/kg SBP, DBP, + LVdp/dt max and − LV dp/dt max greatly decreased. All of these effects were completely blocked by apelin antagonist F13A. 2K1C decreased serum apelin (P < 0.05), did not change ang II and arginine-vasopressin levels, and slightly increased serum aldosterone. Apelin receptor mRNA and protein expression significantly decreased in both ischemic and non-ischemic kidneys.Overall, chronic 2K1C rats showed hypertension and signs of cardiac failure. Apelin in medium doses induced antihypertensive and positive myocardial inotropic effects. Reduction of serum apelin and down regulation of apelin receptors in kidneys of hypertensive rats may play a role in pathophysiology of cardiovascular complications.

Serum apelin is associated with left ventricular hypertrophy in untreated hypertension patients.

BackgroundApelin is an endogenous ligand for the G protein-coupled receptor APJ. The association between apelin and cardiac modeling has been reported. However, if serum apelin affect the left ventricular hypertrophy (LVH) prevalence in hypertensive patients remains unknown.MethodsWe enrolled 344 untreated hypertensive patients. The presence of LVH was determined by echocardiography. The blood was drawn from these patients and serum apelin level was detected. To study the direct effect of apelin on cardiac hypertrophy, cardiomyocytes were cultured and were transfected with apelin gene. Morphometric analysis and measurement of protein contain per cell were then performed.ResultsWe observed a significantly lower serum apelin level in hypertensive patients with LVH compared with those without LVH. Receiver operating characteristic analyses shows that serum apelin level is robust in discriminating patients with LVH from those without. Our in vitro study showed that cellular protein content and cellular size was increased by Ang II treatment, which can be markedly inhibited by the apelin over-expression in cultured cardiomyocytes.ConclusionOur clinical date established a link between apelin and LVH, suggesting serum apelin may be used as a predicator for LVH prevalence in hypertensive patients. The direct evidence in vitro suggest apelin pathway is involved in the cardiomyocyte adaption to hypertrophic stimuli.

The Effect of Different Training Modes on Serum Apelin and Pain Threshold in Morphine-Dependent Rats

Background: Apelin has recently been identified as an analgesic agent and a novel neuropeptide. On the other hand, it has been shown that exercise can lead to reduced pain in morphine-dependent patients. Objectives: Therefore, the aim of this study was to evaluate apelin and pain threshold changes in healthy and morphine-dependent rats in response to two exercise paradigms. Materials and Methods: In this study, 30 healthy and 30 morphine-dependent rats were used. Morphine-dependent and healthy rats were divided into six groups: 1, a control (healthy) group; 2, a healthy endurance group; 3, a healthy strength-training group; 4, an addicted control group; 5, an addicted endurance group; 6, an addicted strength-training group. Then, the training groups performed aerobic and strength training for eight weeks. After the training program, the tail flick and formalin tests were used to assess pain. Apelin was also measured by ELISA. Results: Regardless of the type of exercise, exercise significantly increased the apelin serum levels in healthy rats. The apelin levels significantly increased in the morphine-dependent rats compared with the healthy control group. Endurance, unlike strength training, significantly increased apelin in the serum compared to the addicted control group. The training led to pain relief in the morphinedependent rats and returned it to the healthy control group level. The Pearson correlation showed a reverse significant correlation between the serum apelin level and the tail flick test in the morphine-dependent rats. Conclusions: The results showed that endurance training reduced pain by increasing apelin in morphine-dependent rats. Therefore, it is suggested that this type of training be considered for the morphine-dependent patients for pain relief.

The Effect of Fenugreek (Trigonella foenum-graecum) Seed and 17-β Estradiol on Serum Apelin, Glucose, Lipids, and Insulin in Ovariectomized Rats

Background: Menopause, a natural phenomenon, is defined by the fall of ovarian hormones mainly estrogens causing major problems such as insulin resistance. Fenugreek (Trigonella foenum-graecum) is known to have some useful properties such as insulin sensitizing effect. Apelin is an adipokine, which has several roles such as regulation of insulin secretion. Objectives: The objective of the present study was to evaluate the effect of fenugreek seed and 17-β estradiol on serum Apelin along with glucose, lipids and insulin in ovariectomized rats. Materials and Methods: Forty-nine adult female Wistar rats were randomly divided to seven groups: normal control, ovariectomized control, ovariectomized treated with ethanolic and hexanic extract of fenugreek seed (50 and 150 mg/kg/daily for each), and ovariectomized treated with 17-β estradiol (10 μg/kg/daily) for 42 days. Serum Apelin, glucose, lipids and insulin were measured. Results: Serum Apelin, glucose, lipids and insulin significantly increased in ovariectomized controls in comparison with normal controls (P < 0.05). Serum glucose, lipids and insulin in ovariectomized rats treated with fenugreek seed extract and 17-β estradiol were remarkably lower than ovariectomized controls (P < 0.05). Furthermore, 17-β estradiol caused a significant decrease (P < 0.05) in serum Apelin in ovariectomized rats. Conclusions: It appears that fenugreek seed might be effective against hyperglycemia, hyperlipidemia and insulin resistance in ovariectomized rats without impact on serum Apelin. Furthermore, 17-β estradiol could have similar effects along with possible inhibitory effects on serum Apelin. The complicated role of Apelin in menopause needs to be further explored. Keywords: Apelin-13; Trigonella Foenum-Graecum; 17 Beta-Estradiol; Ovariectomized; Insulin; Lipids

Human Urinary Kallidinogenase Improves Outcome of Stroke Patients by Shortening Mean Transit Time of Perfusion Magnetic Resonance Imaging

Improving cerebral perfusion remains a good option for ischemic stroke for restoring cerebral blood flow. Human urinary kallidinogenase has been shown promising in treating stroke patients. To investigate whether human urinary kallidinogenase's efficacy in treating stroke patients has relationship with improving cerebral perfusion and possible mechanism. Fifty-eight stroke patients in Nanjing Drum Tower Hospital were enrolled in this prospective study. Of them, 29 received human urinary kallidinogenase, while the other 29 were selected as control. National institute health stroke scale, modified Rankin Scale and activities of daily living score were used to determine patient outcome. Cerebral perfusion in patients was determined by perfusion magnetic resonance imaging. Serum apelin and vascular endothelial growth factor were measured by enzyme-linked immunosorbent assay. We confirmed that human urinary kallidinogenase improved stroke outcome in patients. Cerebral perfusion was elevated by human urinary kallidinogenase 12 days after therapy. Human urinary kallidinogenase enhanced vascular endothelial growth factor and APJ expression in stroke patients. The reduced mean transit time was related with favorable outcome analyzed by univariate logistic regression. Human urinary kallidinogenase facilitated stroke recovery and enhanced cerebral reperfusion through up-regulating vascular endothelial growth factor, apelin/APJ pathway.

Omentin and apelin concentrations in relation to obesity, diabetes mellitus type two, and cardiovascular diseases in Egyptian population

Dysregulation of omentin, a beneficial adipokine, and apelin, an inflammatory adipokine, is thought to play a role in the development of type 2 diabetes mellitus and cardiovascular disease. The objective of this study was to evaluate the relationship between circulating omentin and apelin concentrations and components of the metabolic syndrome in adults with and without type 2 diabetes mellitus or cardiovascular disease. A total of 240 adults, sex- and age-matched, were included in the current case–control study, including 80 healthy, non-obese controls, 80 obese patients with T2DM without cardiovascular disease, and 80 obese patients with T2DM with cardiovascular disease. A fasting blood sample was collected to determine biochemical indicators and insulin resistance index (HOMA-IR). Omentin, apelin, interleukin-1β (IL-1β), troponin-T, and oxidized LDL (Ox-LDL) plasma level was assessed by ELISA. Associations of adipokines with biochemical parameters of the patients were determined. Serum omentin levels were significantly lower and serum apelin and IL-1β concentrations were significantly higher in obese diabetic groups compared to non-obese controls. In correlation analyses, omentin negatively associated with the HOMA-IR index, apelin, and troponin-T, whereas apelin was positively associated with IL-1β, BMI, and troponin-T. Our study supports the hypothesis that abnormal production of omentin and apelin can contribute to the pathogenesis of obesity-related complications including T2DM and cardiovascular disease.

The correlational study between serum Apelin and blood lipid level in diabetic retinopathy

Objective To investigate the role of apelin, glycosylated hemoglobin (HbA1c), cholesterol (TC), triglyceride (TG), High density lipoprotein cholesterol (HDLC), low density lipoprotein cholesterol (LDLC) in the development and progress of diabetic retinopathy (DR). Methods The serum concentration of apelin, HbA1c, TC, TG, HDLC and LDLC were measured in 30 normal control subjects and 90 patients with type 2 diabetic mellitus, including 30 cases without DR (NDR), 30 with non-proliferative DR (NPDR), 30 with proliferative DR (PDR). These data were analyzed by SPSS for windows 13.0. Results The serum concentration of apelin, HbA1c, TC, HDLC, LDLC were significantly higher in NDR, NPDR, PDR group than those in control group (F=403.06, 5.45, 4.27, 201.56, 4.90; P 0.05). The serum concentration of apelin, HbA1c, TC, LDLC were significantly higher in NDR, NPDR, PDR group than those in control group (t=0.30, 0.58, 0.79; P<0.05), the serum concentration of HDLC were significantly lower than those in control group(t=0.79, P<0.01). There were significantly positive correlation between the progression of DR and the serum concentration of apelin, HbA1c, TC, LDLC(r=0.962, 0.562, 0.935; P<0.05). There were significantly negative correlation between the progression of DR and the serum concentration of HDLC(r=-0.753, P<0.01). There were correlation between apelin and HbA1c, LDLC and HDLC(r=0.956, 0.741, -0.691; P<0.01). Conclusion Our data demonstrated that serum apelin levels increased significantly in patients with diabetic retinopathy, and are closely related to blood sugar, blood lipid metabolic abnormalities. Key words: Diabetic retinopathy/etiology; Dyslipidemias/metabolism; Adipokines