Apelin Levels Research Articles

Quercetin prevents rats from type 1 diabetic liver damage by inhibiting TGF-ꞵ/apelin gene expression

BackgroundHyperglycemia-induced oxidative stress is a significant contributor to diabetic complications, including hepatopathy. The current survey aimed to evaluate the ameliorative effect of quercetin (Q) on liver functional disorders and tissue damage developed by diabetes mellitus in rats. MethodsGrouping of 35 male Wistar rats was performed as follows: sham; sham + quercetin (sham + Q: quercetin, 50 mg/kg/day in 1 ml 1% DMSO for 6 weeks, by gavage); diabetic control (Diabetes: streptozotocin (STZ), 65 mg/kg, i.p.); diabetic + quercetin 1 (D + Q1: quercetin, 25 mg/kg/day in 1 ml 1% DMSO for 6 weeks, by gavage after STZ injection); and diabetic + quercetin 2 (D + Q2: quercetin, 50 mg/kg/day in 1 ml 1% DMSO for 6 weeks, by gavage after STZ injection). Body weight, food intake, and water intake were measured. Ultimately, the samples of plasma and urine, as well as tissue samples of the liver and pancreas were gathered for later assays. ResultsSTZ injection ended in elevated plasma blood glucose levels, decreased plasma insulin levels, liver dysfunction (increased activity levels of AST, ALT, and ALP, increased plasma levels of total bilirubin, cholesterol, LDL, triglyceride, decreased plasma levels of total protein, albumin and HDL), enhanced levels of malondialdehyde, diminished activities of antioxidant enzymes (superoxide dismutase, and catalase), reduced level of glutathione (GSH) increased gene expression levels of apelin and TGF-ꞵ, plus liver histological destruction. All these changes were diminished by quercetin. However, the measure of improvement in the D + Q2 group was higher than that of the D + Q1 group. ConclusionsQuercetin improved liver function after diabetes mellitus type 1, possibly due to reduced lipid peroxidation, increased antioxidant systems, and inhibiting the apelin/TGF-ꞵ signaling pathway.

Gingival crevicular fluid levels of apelin correlates with clinical periodontal diagnosis.

Limitations of clinical periodontal measurements have led to the search for reliable biomarkers that can be used in diagnosis and monitoring of periodontal diseases. Considering the relationship of adipokines with periodontal disease, diabetes, and obesity, apelin may be a biomarker for periodontal diseases due to its modulating effects on inflammation. The present study was conducted to determine gingival crevicular fluid (GCF) apelin levels in systemically healthy individuals and to evaluate the potential of apelin as a biomarker for periodontal diagnosis. Ten individuals with clinically healthy periodontal tissues, 10 patients diagnosed with gingivitis, and 10 patients with periodontitis were included in the present study. Whole mouth clinical periodontal measurements were recorded and GCF samples were obtained from the buccal approximal regions of single-rooted teeth with features that would represent clinical periodontal diagnosis. Apelin level in the samples was determined by ELISA. Clinical and biochemical findings were statistically analyzed. Possible relationship between the variables was evaluated with Pearson correlation analysis. Apelin level in the gingivitis group was higher than that in the clinically healthy group (p = 0.000) and lower than that in the periodontitis group (p = 0.000). A positive correlation was found between GCF apelin concentration and plaque score, bleeding on probing, and probing depth (p = 0.000). Within the limits of this study, it can be suggested that GCF apelin concentration may be a biomarker that can distinguish between healthy periodontal tissues, gingivitis, and periodontitis patients. Apelin concentration in the gingival crevicular fluid may aid in the diagnosis of periodontal disease.

Apelin as a potential marker in Iraqi children with Type 1 Diabetes Mellitus

Objective: This study aims to evaluate apelin levels and their correlation with key metabolic parameters in pre-pubertal and pubertalindividuals with type 1 diabetes in Iraq, providing insights into apelin's role in diabetes pathogenesis and its potential as an early diagnostic marker for cardiovascular disease. Methods: Ninety children, divided into pre-pubertal T1DM, pubertal T1DM, and healthy subjects, underwent measurements of variousbiochemical parameters, including apelin, fasting blood glucose, lipid profile, and thyroid hormones. Results: Positive correlations (P < 0.01) were found between apelin levels and FSB, TG, BMI, HbA1c, TC, TSH, and a negative correlation with HDL-C in pubertal and pre-pubertal groups, revealing potential links between apelin, glucose, and insulin sensitivity. Conclusion: The study suggests apelin's involvement in diabetes pathogenesis, highlighting its rise in adulthood as an indicator of diabetes complications and its potential use as a diagnostic marker for early detection of cardiovascular disease in individuals with T1DM.

Comparative Evaluation of Adipokine Metrics for the Diagnosis of Gestational Diabetes Mellitus.

Gestational diabetes mellitus (GDM) is one of the most common medical disorders in pregnancy. Adipokines, predominantly secreted by adipose tissue, are involved in numerous metabolic processes. The exact role of adipokines in the pathogenesis of GDM is still not well known, and numerous adipokines have been analysed throughout pregnancy and proposed as biomarkers of GDM. This study aimed to evaluate serum adiponectin, chemerin, lipocalin and apelin levels in GDM and non-GDM women, to assess them as clinically useful biomarkers of the occurrence of GDM and to demonstrate the correlation between the levels of the above adipokines in the blood serum and the increased risk of the development of GDM. The role of these adipokines in the pathogenesis of GDM was also analysed. The statistically significant differences between the levels of adiponectin (7234.6 vs. 9837.5 ng/mL, p < 0.0001), chemerin (264.0 vs. 206.7 ng/mL, p < 0.0001) and lipocalin (39.5 vs. 19.4 ng/mL, p < 0.0001) were observed between pregnant women with GDM and healthy ones. The diagnostic usefulness of the tested adipokines in detecting GDM was also assessed. The research results confirm the hypothesis on the significance of adiponectin, chemerin, lipocalin and apelin in the pathophysiological mechanisms of GDM. We speculate that these adipokines could potentially be established as novel biomarkers for the prediction and early diagnosis of GDM.

Circulating apelin, IL22RA2 and VEGF in pre-capillary pulmonary hypertension.

Cytokines can modulate vascular remodelling and the adaptation of the right ventricle in pre-capillary pulmonary hypertension (PH). However, detailed data on the circulating levels of cytokines in patients are limited. We measured blood cytokine concentration in 39 treatment-naïve patients (pulmonary arterial hypertension: N = 16, chronic thromboembolic PH: N = 15, PH due to lung disease: N = 8) and 12 control subjects using enzyme-linked immunoassays. Apelin concentration >1,261 ng/mL identified patients with PH (66% sensitivity and 82% specificity), and in patients it was related to systolic pulmonary arterial pressure (PAP) (r = 0.33, P = 0.04), right atrial pressure (r = 0.38, P = 0.02), cardiac index (r=-0.34, P = 0.04), and right ventricular stroke work index (r = -0.47, P = 0.003). IL22RA2 concentration correlated with mean PAP (r = -0.32, P = 0.04) and serum N-terminal pro B-type natriuretic peptide level (r = -0.42, P = 0.01). VEGF concentration increased in patients upon clinical improvement (N = 16, P = 0.02). Circulating apelin is a novel biomarker of pre-capillary PH. Apelin and IL22RA2 levels are related to right ventricular function upon diagnosis of PH.

Apelin and the gut microbiome: Potential interaction in human MASLD

BackgroundMetabolic dysfunction-associated steatotic liver disease (MASLD) is a leading cause of chronic liver disease with increasing numbers worldwide. Adipokines like apelin (APLN) can act as key players in the complex pathophysiology of MASLD. AimsInvestigating the role of APLN in MASLD. MethodsFecal and blood samples were collected in a MASLD cohort and healthy controls (HC). MASLD patients with liver fibrosis and MASLD-associated hepatocellular carcinoma (HCC) were included into the study. Systemic concentration of Apelin, Apelin receptor (APLNR) and circulating cytokines were measured in serum samples. ResultsApelin concentration correlated with the Fib-4 score and was elevated in MASLD patients (mild fibrosis, mF (Fib-4 <3.25) and severe fibrosis, sF (Fib-4 >3.25)) as well as in MASLD-associated HCC patients compared to HC. In accordance APLNR and circulating cytokines were also elevated in mF and sF. In contrast apelin levels were negatively associated with liver survival at three and five years. Changes in taxa composition at phylum level showed an increase of Enterobactericae, Prevotellaceae and Lactobacillaceae in patients with sF compared to mF. We could also observe an association between apelin concentrations and bacterial lineages (phyla). ConclusionsCirculating apelin is associated with liver fibrosis and HCC. In addition, there might exist an interaction between systemic apelin and the gut microbiome.

Evaluation of some heart enzymes and Iron levels in β-thalassemia patients in Thi-Qar City, Iraq

Beta thalassemia is one of the most common hereditary diseases in the world caused by a deficiency of globin chains. Heart disease is one of the main complications of this disease as a result of excess iron deposition in the cardiac tissues. Total of 100 patients of 2-18 years diagnosed with ß-TM were employed in the current study and admitted to Thi-Qar Center of Hereditary Blood Diseases in Thi-Qar city, Iraq, and 80 healthy participants, matched by age, and geographical area were adopted as control group. The current study included evaluating of serum Troponin I (c.TnI), Creatine kinase-MB isoenzyme (CK-MB), Apelin, aspartate aminotransferase (AST), and Lactate Dehydrogenase enzyme (LDH) of studied groups. The finding revealed a significant increase (p&lt;0.01) of c.TnI, CK-MB, AST, and LDH levels as well as a significant decrease (p&lt;0.01) in apelin level in all patients with ß-TM compared to the control group. Pearson's correlation coefficient (r) was also found between the biochemical parameters studied for ß-TM patients with ferritin level, were found a significant correlation (p&lt;0.01) between ferritin level with CK-MB, LDH, and AST levels while there was no significant correlation (P&gt;0.01) through apelin and c.TnI levels. The finding showed a clinical predictor to damage cardiac tissues in the near term, which portends the use of more efficient treatment protocols to remove excess iron from ß-TM patients.

Astaxanthin Supplementation Augments the Benefits of CrossFit Workouts on Semaphorin 3C and Other Adipokines in Males with Obesity.

Regular physical activity and the use of nutritional supplements, including antioxidants, are recognized as efficacious approaches for the prevention and mitigation of obesity-related complications. This study investigated the effects of 12 weeks of CrossFit training combined with astaxanthin (ASX) supplementation on some plasma adipokines in males with obesity. Sixty-eight males with obesity (BMI: 33.6 ± 1.4 kg·m-2) were randomly assigned into four groups: the control group (CG; n = 11), ASX supplementation group (SG; n = 11), CrossFit group (TG; n = 11), and training plus supplement group (TSG; n = 11). Participants underwent 12 weeks of supplementation with ASX or placebo (20 mg/day capsule daily), CrossFit training, or a combination of both interventions. Plasma levels of semaphorin 3C (SEMA3C), apelin, chemerin, omentin1, visfatin, resistin, adiponectin, leptin, vaspin, and RBP4 were measured 72 h before the first training session and after the last training session. The plasma levels of all measured adipokines were significantly altered in SG, TG, and TSG groups (p < 0.05). The reduction of resistin was significantly higher in TSG than in SG (p < 0.05). The plasma levels of omentin1 were significantly higher in both training groups of TG and TSG than SG (p < 0.05), although such a meaningful difference was not observed between both training groups (p > 0.05). Significant differences were found in the reductions of plasma levels of vaspin, visfatin, apelin, RBP4, chemerin, and SEMA3C between the SG and TSG groups (p < 0.05). The study found that a 12-week intervention using ASX supplementation and CrossFit exercises resulted in significant improvements in several adipokines among male individuals with obesity. Notably, the combined approach of supplementation and training had the most pronounced results. The findings presented in this study indicate that the supplementation of ASX and participation in CrossFit exercise have the potential to be effective therapies in mitigating complications associated with obesity and enhancing metabolic health.

Content of adipokines and myokines in the blood of children and adolescents with obesity with polymorphism of the gene of liver triacylglycerol lipase rs2070895

BACKGROUND: A special role in the development of obesity is given to the genetic polymorphism of lipid metabolism enzymes, which include triacylglycerol lipase. However, there is still no information about the relationship between the single nucleotide polymorphism (snp) of the triacylglycerol lipase (LIPC) gene and the state of the endocrine function of mesenchymal tissues in childhood and adolescence obesity.AIM: The aim of the work was to study the relationship between snp LIPC for rs2070895 and changes in the content of adipokines, myokines, and the values of blood lipid metabolism in obese children and adolescents with different sexes.MATERIALS AND METHODS: In 96 healthy children and adolescents of different sexes and 98 obese peers, a study was conducted to assess the snp of the LIPC by rs2070895. In the blood serum of the examined, the content of total cholesterol, HDL cholesterol, LDL cholesterol, VLDL cholesterol, triacylglycerols, glucose, activity of alanine aminotransferase and aspartate aminotransferase, as well as the level of leptin, adiponectin, resistin, apelin, irisin, adipsin, myostatin, FGF21, osteocrine, oncostatin M , insulin and asprosin.RESULTS AND DISCUSSION: It has been established that obesity in boys is accompanied by hyperleptinemia, the occurrence of insulin resistance and disorders of blood lipid metabolism. In carriers of the heterozygous allele -250G/A, dyslipidemia and atherogenesis decrease in obesity, but alteration of internal organs increases. In girls with different LIPC genotypes for rs2070895, with obesity, there is an increase in the level of leptin and apelin, as well as irisin and insulin in the blood. In girls with the homozygous allele -250G/G, in addition to that, the content of resistin, asprosin and prolactin decreases in the blood, which is not are typical for girls with the heterozygous allele -250G/A. In obese girls with the heterozygous allele, the levels of adipsin, FGF-21, oncostatin M, and osteocrine increase, which are not typical for obese girls with the homozygous allele. Against the background of changes in the content of adipokines and myokines in girls homozygous for LIPC, obesity occurs dyslipemia, which is not typical for girls with the heterozygous allele -250G/A.CONCLUSION: The snp of LIPC at rs2070895 has sex-dependent effects on the levels of adipokines, myokines, and parameters lipid metabolism in the blood.

Abstract 13047: The Modulatory Effects of Perivascular Adipose Tissue on the Renal Arterial Vasorelaxation and Its Relationship With Kidney Function in Metabolic Syndrome

Metabolic syndrome (MetS) is a cluster condition that increases the risk of cardiovascular diseases and type 2 diabetes. Perivascular adipose tissue (PVAT) regulates the arterial tone. We have demonstrated that the renal arterial PVAT enhances the vasorelaxation response in MetS model strains, SHRSP.Z- Lepr fa /IzmDmcr rats (SPZF) and SHR/NDmcr-cp rats (CP). Furthermore, we have found that overactivation of angiotensin II type 1 receptor (AT1R) signaling and a decrease in apelin levels in PVAT leads to a decline in compensatory PVAT effects. MetS is associated with chronic kidney disease, and the dysfunction of the PVAT favoring the vasorelaxation response could be a reason for kidney disease development. Therefore, we investigated the relationship between PVAT function and kidney function using MetS model rats.Renal arteries were isolated from the male and female SPZF and CP at 23 weeks of age. Vasorelaxation and mRNA transcript levels in PVAT were examined using organ bath methods and quantitative real-time polymerase chain reaction, respectively. Systolic blood pressure (sBP) was measured using a tail-cuff method. Insulin, glucose, and creatinine in the serum and protein in the urine were measured using commercial kits and eGFR, and the HOMA-IR were calculated.sBP was higher in SPZF than CP, but lower in females than males. HOMA-IR and urine protein levels were the lowest, while eGFR and enhancing effects of PVAT on acetylcholine-induced relaxations were the highest in female CP among the groups. eGFR was negatively correlated with sBP, HOMA-IR, and urinary protein levels. The enhancements of relaxations by PVAT were negatively correlated with sBP, HOMA-IR, and AT1R activity in PVAT.This study suggests that the insulin resistance and high blood pressure are associated with PVAT dysfunction, resulting from AT1 activation in PVAT, while it does not support the hypothesis that the disappearance of the effects of PVAT directly leads to kidney dysfunction.

Effect of Swimming Training on Cardiac Morphological Factors, Apelin and Insulin like Growth Factor-1 in Male Wistar Rats

Introduction: Different training methods have cardioprotective effects. The aim of this study was to examine the potential protective impact of continuous and interval swimming training with weights on cardiac morphological factors and serum levels of Apelin and Insulin-like Growth Factor-1 in male Wistar rats.&#x0D; Methods: In this experimental study, 27 male rats divided randomly into the control (n=6), sham (n=5), interval (n=8) and endurance (n=8) groups. The endurance group swam for 12 weeks/5 days while swimming time increased incrementally. During the 12-week/4-day period, the interval group engaged in swimming exercises while gradually increasing the load and reducing the duration of rest. Apelin and Insulin like Growth Factor-1 concentration, heart weight and left ventricle weight were measured. One-way ANOVA was utilized and Tuckey-HSD test was used to point out the place of significance (α ≤ 0.05).&#x0D; Results: Findings showed that total heart weight in interval and endurance training compared to the control (P= 0.02 and P= 0.02 respectively) and sham (P= 0.02 and P= 0.02, respectively) significantly increased. Furthermore, the weight of the left ventricle showed a significant increase following endurance training in comparison to both the control (P= 0.02) and the sham groups (P= 0.02). Additionally, it was found to be significantly higher than the sham group following interval training. (P= 0.01). Apelin significantly increased in interval and endurance training compared to the control (P= 0.00 and P= 002 respectively) and sham groups (P= 0.02 and P= 0.04, respectively). Moreover, insulin like growth factor-1 significantly increased in interval and endurance training compared to the control (P= 0.01 and P= 0.01, respectively).&#x0D; Conclusion: It appears that a 12-week swimming training program, particularly in an interval format, can induce physiological hypertrophy in cardiac tissue and provide cardiac protective benefits through the upregulation of Insulin-like Growth Factor-1 and Apelin.

The Association of Adipokines and Myokines in the Blood of Obese Children and Adolescents with Lipoprotein Lipase rs328 Gene Variants.

Obesity develops largely due to genetic factors, with the genetic polymorphism of lipid metabolism enzymes being of particular importance. However, it is still unclear how the genetic variants of one of the key enzymes in lipid transport, lipoprotein lipase (LPL), are associated with the endocrine function of mesenchymal tissues in obesity. The current study was aimed at the investigation of the LPL rs328 gene variant association with adipokines and myokines levels, as well as lipid metabolism indices in the blood of children and adolescents of both genders with obesity. We found that LPL polymorphism rs328 is not characterized by the differences in the levels of hormones, adipokines, and myokines and in the blood of healthy children and adolescents; however, it significantly affects these indices during obesity in gender-dependent manner. The shifts in hormones, adipokines, and myokines manifest mostly in the obese individuals with Ser447Ser genotype rather than with 447Ter genotype. Obese boys homozygous for Ser447Ser have more elevated leptin levels than girls. They also demonstrate lower adiponectin, apelin, prolactin, and osteocrine levels than those in obese girls with the same genotype. The gender-based differences are less pronounced in individuals with 447Ter genotype than in the homozygotes for 447Ser. Thus, we conclude that the polymorphism rs328 of the lipoprotein lipase gene is accompanied by the changes in hormones, adipokines, and myokines levels in the blood of children and adolescents with obesity in gender-dependent manner.

Effects of Apelin on the fibrosis of retinal tissues and Müller cells in diabetes retinopathy through the JAK2/STAT3 signalling pathway

Retinal fibrosis was a key characteristic of diabetes retinopathy (DR). Apelin was found to be a candidate for tissue fibrosis. Nevertheless, the role of Apelin in the Müller cells in DR remains unclear. This study identified the function and mechanism of Apelin in Müller cells and the fibrosis of retinal tissue. Western blot was carried out to detect the Apelin, GFAP, Collagen I, α-SMA, JAK2 and STAT3 protein levels. Masson staining was performed to display the histopathological changes in retinal tissue of diabetic mellitus (DM) rats. The immunofluorescence staining was conducted to evaluate the Apelin levels in the retinal tissue. The levels of GFAP, Collagen I and α-SMA in the retinal tissue of DM rats was visualised by the immunohistochemistry staining. The results showed that Apelin, GFAP, Collagen I andα-SMA expression was prominently elevated in the retinal tissue of DM rats and high glucose (HG)-exposed Müller cells. The results of Masson staining showed that the epiretinal fibrotic membrane was observed in DM rats. Apelin knockdown declined the GFAP, Collagen I andα-SMA levels. Besides, the protein levels of p-JAK2 and p-STAT3 were elevated in the HG-treated Müller cells, while Apelin knockdown declined them. FLLL32 treatment neutralised the role of Apelin. In conclusion, Apelin facilitated the fibrogenic activity of Müller cells through activating the JAK2/STAT3 signalling pathway, and thus inducing the retinal fibrosis in DR.

Apelin/APJ system protects placental trophoblasts from hypoxia-induced oxidative stress through activating PI3K/Akt signaling pathway in preeclampsia

BackgroundPreeclampsia is a placentally induced syndrome with diverse clinical presentation that currently has no cure. Oxidative stress is a potent inducer of placental dysfunction. The apelin receptor (APJ) system is a pleiotropic pathway with a potential for therapeutic targeting in preeclampsia. This study examines the alteration of circulating apelin levels and placental APJ expression in preeclampsia and investigates whether apelin/APJ system can protect placental trophoblast from hypoxia-induced oxidative stress injury through PI3K/AKT signaling pathway. ResultsOur results confirmed that maternal apelin concentration was increased in women with preeclampsia, but APJ expression was reduced in the preeclamptic placentas. Apelin-13 treatment not only specifically attenuated CoCl2-induced superoxide production, but also prevented CoCl2-induced reduction of SOD activity and SOD1 expression. In addition, apelin-13 suppressed CoCl2-induced apoptosis by increasing the expression of bcl-2/bax ratio and by decreasing the expression of active caspase-3 in placental trophoblasts. Furthermore, we found that apelin-13 binding APJ activated the PI3K and AKT kinases and inhibition of PI3K kinase significantly blocked the anti-oxidative effects of apelin-13 in placental trophoblasts. ConclusionsDecrease of placental APJ expression is associated with oxidative stress-induced placental dysfunction in preeclampsia, and increased circulating apelin could be a moderately successful marker to differentiate subjects with preeclampsia from healthy pregnant women. Inhibition of superoxide production and caspase-3 cleavage, together with upregulation of SOD activity/expression and bcl-2/bax ratio, could be the potential molecular mechanisms by which apelin-13/APJ protects placental trophoblasts from oxidative stress injury.

Parental History of Hypertension: A Risk for Autonomic Dysfunction and Metabolic and Vascular Derangement in Normotensive Male Offspring.

Children of hypertensive parents have an increased propensity of developing hypertension, at an age very much prior to their parents. Understanding the pathophysiology of hypertension in such young individuals, especially baroreflex sensitivity (BRS), is necessary. Reduced heart rate variability (HRV), insulin resistance (IR), dyslipidemia, and decreased vasodilatory adipokines, namely, apelin and relaxin, in normotensives may predispose to the onset of hypertension. Thus, this study compared autonomic functions, vascular markers, and metabolic profiles between normotensive male offspring with and without parental hypertension. This analytical cross-sectional study comprised 40 male normotensive offspring of hypertensive parents, aged 18-35 years, recruited as the study group and 40 age- and body mass index (BMI)-matched normotensive male offspring with non-hypertensive parents enrolled as controls. Cardiovascular autonomic functions, including BRS, HRV, diastolic blood pressure response to isometric handgrip test (ΔDBPIHG), Valsalva ratio, and metabolic and vascular markers, were assessed. The study group exhibited reduced BRS, HRV, and Valsalva ratio and higher ΔDBPIHG compared to controls, indicating impaired autonomic functions. The study group had higher IR and triglyceride levels and reduced apelin and relaxin levels. BRS showed significant correlations with HRV, Valsalva ratio, ΔDBPIHG, and metabolic and vascular markers. Normotensive male offspring of hypertensive parents exhibit impaired autonomic functions, as evidenced by reduced BRS, HRV, and Valsalva ratio. Additionally, they have higher IR, dyslipidemia, and decreased levels of vasodilatory adipokines, indicating an increased risk for future hypertension development. These findings signify that early identification of hypertensive potential in this high-risk population is warranted, which would enable taking necessary preventive measures.

The profile of adipokines associated with fibrosis and impaired microcirculation in systemic sclerosis

PurposeAdipokines belong to a group of molecules mostly produced by adipose tissue. Abnormalities in the secretion of several adipokines have already implicated to play a pathogenic role in systemic sclerosis (SSc). However, the possible role of numerous molecules still needs to be clarified. The aim of the study was to determine whether the altered level of selected circulating adipokines might correlate with the intensity of fibrosis and vasculopathy in the course of SSc. Materials and methodsSerum concentrations of chemerin, adipsin, retinol-binding protein 4, apelin, visfatin, omentin-1, and vaspin were determined with ELISA in the sera of patients with SSc (n ​= ​55) and healthy controls (n ​= ​25). ResultsThe serum concentration of adipsin (p ​= ​0.03) and visfatin (p ​= ​0.04) was significantly increased and the level of retinol-binding protein 4 (p ​= ​0.03) was decreased in diffuse compared to limited cutaneous SSc. Moreover, serum adipsin level correlated positively with the intensity of skin fibrosis measured with the modified Rodnan skin score (r ​= ​0.31, p ​= ​0.02) and was significantly higher in patients with pulmonary arterial hypertension than in those without the condition (p ​= ​0.03). The concentrations of adipsin (p ​= ​0.01) and visfatin (p ​= ​0.04) were significantly increased and the level of apelin (p ​= ​0.02) was decreased in patients with active digital ulcerations compared to individuals without this complication. ConclusionAdipsin may be considered a pivotal protein in the development of both fibrosis and impaired microcirculation. Its abnormal concentration reflects the intensity of skin thickening and the presence of pulmonary arterial hypertension. Adipsin, visfatin, and apelin are adipose tissue-derived molecules associated with digital vasculopathy.

Assessment of Serum Apelin Level in Iraqi Type 2 Diabetic Nephropathy Patients

The present study is investigated the relationship between Apelin concentration and various biochemical parameters in patients with type2 diabetic nephropathy. A total of 30 patients diagnosed with Diabetic Nephropathy at Al-Yarmouk and Al-Karama teaching hospitals were included in the study and compared to 40 healthy individuals forming the control group. The study was identified a significant increase in Apelin concentration among patients with type 2 diabetic nephropathy, compared to the control group. Additionally, various biochemical parameters were analyzed, and a strong correlation was found between their concentrations and Apelin levels. Considerable elevation of serum nitrogen compounds like urea and creatinine, as well as fasting blood glucose and glycated hemoglobin (HbA1c) were observed in the type 2 diabetic nephropathy patients. A positive correlation between Apelin and both creatinine and glycated hemoglobin levels was observed. Conversely, a negative correlation was observed between Apelin and the glomerular filtration rate (GFR), indicating potential implications for kidney function in these patients. These findings emphasize the significance of monitoring Apelin concentration along with other biochemical variables as essential indicators for the management and understanding of type 2 diabetic nephropathy. Further research in type 2 diabetic nephropathy could offer valuable insights into potential interventions and treatment strategies for improving patient outcomes.

Quercetin Attenuates Atherosclerosis via Modulating Apelin Signaling Pathway Based on Plasma Metabolomics.

To interpret the pharmacology of quercetin in treatment of atherosclerosis (AS). Fourteen apolipoprotein E-deficient (ApoE-/-) mice were divided into 2 groups by a random number table: an AS model (ApoE-/-) group and a quercetin treatment group (7 in each). Seven age-matched C57 mice were used as controls (n=7). Quercetin [20 mg/(kg·d)] was administered to the quercetin group intragastrically for 8 weeks for pharmacodynamic evaluation. Besides morphological observation, the distribution of CD11b, F4/80, sirtuin 1 (Sirt1) and P21 was assayed by immunohistochemistry and immunofluorescence to evaluate macrophage infiltration and tissue senescence. Ultra-performance liquid chromatography/tandem mass spectrometry (UPLC-MSC/MS) was performed to study the pharmacology of quercetin against AS. Then, simultaneous administration of an apelin receptor antagonist (ML221) with quercetin was conducted to verify the possible targets of quercetin. Key proteins in apelin signaling pathway, such as angiotensin domain type 1 receptor-associated proteins (APJ), AMP-activated protein kinase (AMPK), peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), tissue plasminogen activator (TPA), uncoupling protein 1 (UCP1) and angiotensin II receptor 1 (AT1R), were assayed by Western blot. Quercetin administration decreased lipid deposition in arterial lumen and improved the morphology of ApoE-/- aortas in vivo. Quercetin decreased the densities of CD11b, F4/80 and P21 in the aorta and increased the level of serum apelin and the densities of APJ and Sirt1 in the aorta in ApoE-/- mice (all P<0.05). Plasma metabolite profiling identified 118 differential metabolites and showed that quercetin affected mainly glycerophospholipids and fatty acyls. Bioinformatics analysis suggested that the apelin signaling pathway was one of the main pathways. Quercetin treatment increased the protein expressions of APJ, AMPK, PGC-1α, TPA and UCP1, while decreased the AT1R level (all P<0.05). After the apelin pathway was blocked by ML221, the effect of quercetin was abated significantly, confirming that quercetin attenuated AS by modulating the apelin signaling pathway (all P<0.05). Quercetin alleviated AS lesions by up-regulation the apelin signaling pathway.

Expression of Apelin in Rotator Cuff Tears and Examination of Its Regulatory Mechanism: A Translational Study.

Inflammatory mediators play important roles in the pain associated with rotator cuff tears (RCTs), but their underlying mechanisms are unclear. Apelin, a neuropeptide, is upregulated under inflammatory conditions and possibly contributes to pain induced by rotator cuff tears. This translational study aimed to examine apelin expression and regulation by tumor necrosis factor alpha (TNF-α) in patients with RCT and in rat RCT models. Synovial tissues were harvested from the glenohumeral joints of the shoulders in 46 patients who underwent arthroscopic Bankart repair for recurrent shoulder dislocations (RSDs) or arthroscopic rotator cuff repair for RCTs. The harvested tissues were extracted and processed by reverse transcriptase-polymerase chain reaction (RT-PCR). Rats underwent sham or RCT surgery; the rotator cuff tissues were extracted 1, 7, 14, 28, and 56 days after surgery and analyzed for mRNA expression levels of the TNF-α and apelin using RT-PCR. The cultured rotator cuff cells (RCCs) were stimulated with TNF-α to examine their role in the regulation of apelin expression. Apelin expression was higher in the RCT group than in the RSD group and significantly correlated with pain intensity. In rats, the expression was also higher in RCT. Apelin expression significantly increased during the acute and chronic phases in rats. In cultured RCCs, apelin mRNA levels significantly increased after TNF-α stimulation. Apelin levels were regulated by TNF-α and were highly expressed in patients with RCT and rats in RCT models. Thus, apelin may be a new pain management target for RCTs.

Assessment of Serum Apelin Levels and Its Relation to Insulin Resistance in Acne Vulgaris Patients

Abstract Introduction Apelin is one of the adipokines. Acne vulgaris is a very common dermatological disease with a multifactorial background and hyperinsulinemia and insulin resistance are considered to play a pivotal role in its development and severity. Aim To evaluate serum apelin levels in acne vulgaris patients and to reveal the possible relation between its serum levels and the insulin resistance state in acne vulgaris patients. Material and methods Thirty-two acne vulgaris patients and thirty-two healthy controls were enrolled into the study. The blood levels of apelin, insulin and glucose were measured in patients and controls. Homeostasis model assessment index (HOMA-IR) was calculated to evaluate the insulin resistance state. Results Acne vulgaris patients experienced significant higher levels of fasting insulin, serum apelin, and HOMA-IR compared to controls. Conclusions These results suggest that serum apelin and insulin resistance may have a role in the pathogenesis of acne.