Increased Serum Level of Growth Differentiation Factor 15 (GDF-15) is Associated with Coronary Artery Disease

Role of GDF-15 in diabetic nephropathy: mechanisms, diagnosis, and therapeutic potential

PURPOSE

Growth differentiation factor 15 (GDF-15) is a cytokine involved in regulating homeostasis, and its expression is up-regulated in response to injury, stress, and inflammation. This study explored the role of GDF-15 in diabetic nephropathy (DN), a severe complication of diabetes mellitus, and its potential as a biomarker for disease progression.

METHODS

As a member of the transforming growth factor-β superfamily, GDF-15 exhibits its renal protective functions primarily through its anti-inflammatory effects and the up-regulation of other renal protective factors. This study evaluated the association between circulating GDF-15 levels and DN progression, examining the underlying mechanisms.

RESULTS

Circulating GDF-15 levels are closely linked to the development and progression of DN. While existing research has yielded some consistent conclusions, a comprehensive understanding of the role of GDF-15 in DN pathogenesis is needed to identify new therapeutic targets and strategies.

CONCLUSION

GDF-15 has the potential to be a prognostic and diagnostic biomarker for DN. It is crucial to establish appropriate reference ranges and explore their clinical utility in routine practice for validating the role of GDF-15 in DN management. Further interventional studies are required to confirm its clinical value in diagnosing and predicting the progression of DN.

Serum Growth Differentiation Factor 15 Levels Predict the Incidence of Frailty among Patients with Cardiometabolic Diseases

INTRODUCTION

Frailty is a crucial health issue among older adults. Growth differentiation factor 15 (GDF15) is associated with inflammation, oxidative stress, insulin resistance, and mitochondrial dysfunction, which are possible pathogeneses of frailty. However, few longitudinal studies have investigated the association between GDF15 and the incidence of frailty. Therefore, we investigated whether high serum GDF15 levels are associated with the incidence of frailty.

METHODS

A total of 175 older adults (mean age: 77 ± 6 years; 63% women) with cardiometabolic diseases and no frailty out of the two criteria at baseline participated. Individuals with severe renal impairment or severe cognitive impairment were excluded. Serum GDF15 levels were measured at baseline. Patients were asked to assess frailty status at baseline and annually during follow-up using the modified version of the Cardiovascular Health Study (mCHS) and the Kihon Checklist (KCL). We examined the association between GDF15 tertiles and each frailty measure during follow-up (median 38-39 months). In the multivariate Cox regression analysis, with the GDF15 tertile groups as the explanatory variables, hazard ratios (HRs) and 95% confidence intervals (CIs) for incident frailty were calculated after adjusting for covariates and using the lowest tertile group as the reference.

RESULTS

During the follow-up period, 25.6% and 34.0% of patients developed frailty, as defined by the mCHS and KCL, respectively. The highest GDF15 tertile group had a significantly higher incidence of mCHS- or KCL-defined frailty than the lowest GDF15 tertile group. Multivariate Cox regression analysis revealed that the adjusted HRs for incident mCHS- and KCL-defined frailty in the highest GDF15 tertile group were 3.9 (95% CI: 1.3-12.0) and 2.7 (95% CI: 1.1-6.9), respectively.

CONCLUSION

High serum GDF15 levels predicted the incidence of frailty among older adults with cardiometabolic diseases and could be an effective marker of the risk for frailty in interventions aimed at preventing frailty, such as exercise and nutrition.

The association between growth differentiation factor 15 and presence and severity of coronary atherosclerosis

PURPOSE

Growth differentiation factor 15 (GDF-15) is a member of the transforming growth factor beta superfamily and is faintly expressed under healthy conditions. GDF-15 is markedly elevated in a variety of diseases, including coronary artery disease (CAD), atrial fibrillation and heart failure. Here, we aimed to investigate the association of GDF-15 with the extent and severity of CAD in patients with stable CAD.

METHODS

We enrolled 129 patients undergoing coronary angiography for the evaluation of stable CAD in the study. SYNTAX and SYNTAX II PCI/CABG scores were calculated. The CAD (+) study group was also stratified into two groups (high and low GDF-15) with respect to the mean GDF-15 value. Correlation and regression analyses were performed for further evaluation.

RESULTS

Of the 129 patients, 75 had CAD. GDF-15 values were higher in the CAD (+) group (p ​< ​0.001). The two groups were compared according to a cut-off value of 2451.77. SYNTAX and SYNTAX II PCI/CABG scores were significantly associated with the high GDF-15 group (p ​< ​0.001). Additionally, correlation analysis showed a strong positive correlation between GDF-15 and SYNTAX (r: 0.859, p ​< ​0.001), SYNTAX II PCI (r: 0.921, p ​< ​0.001) and SYNTAX II CABG (r: 0.874, p ​< ​0.001) scores. Multivariate analysis identified GDF-15 as an independent predictor of CAD.

CONCLUSION

GDF-15 is an independent predictor of CAD and is associated with CAD severity in terms of SYNTAX, SYNTAX II PCI and SYNTAX II CABG scores.

Evaluation of Arterial Stiffness Parameters and the Growth Differentiation Factor-15 Level in Patients with Premature Myocardial Infarction

BACKGROUND

Myocardial infarction (MI) is increasing at a younger age. Growth differentiation factor-15 (GDF-15) has been implicated in several key mechanisms of atherogenesis. Arterial stiffness parameters, including pulse wave velocity (PWV) and the augmentation index (AIx), can indicate the presence or progression of atherosclerosis. The aim of this study is to evaluate the GDF-15 level and arterial stiffness parameters in patients with premature MI.

METHOD

Thirty patients aged ≤45 years (mean age: 39 ± 5 years, 23 male) who recovered from a MI and 15 age and sex-matched subjects were consecutively included. The serum GDF-15 concentration levels and arterial stiffness parameters of the patients and controls were measured.

RESULTS

GDF-15 levels were significantly higher in patients with premature MI, while there were no significant differences in PWV and AIx between the groups. The GDF-15 level was correlated negatively with high-density lipoprotein (HDL) cholesterol and positively with uric acid levels. Both GDF-15 (p = 0.046, odds ratio: 1.092, 95% confidence interval: 1.003-1.196) and HDL cholesterol (p = 0.037, odds ratio: 0.925, 95% confidence interval: 0.859-0.995) were found as independent factors associated with premature MI.

CONCLUSIONS

GDF-15 could be a risk factor for premature MI. Further studies are needed to elucidate the central role of GDF-15 in the pathophysiology of early atherosclerosis and MI in the young population.

Novel Biomarkers for Atherosclerotic Disease: Advances in Cardiovascular Risk Assessment

Atherosclerosis is a significant health concern with a growing incidence worldwide. It is directly linked to an increased cardiovascular risk and to major adverse cardiovascular events, such as acute coronary syndromes. In this review, we try to assess the potential diagnostic role of biomarkers in the early identification of patients susceptible to the development of atherosclerosis and other adverse cardiovascular events. We have collected publications concerning already established parameters, such as low-density lipoprotein cholesterol (LDL-C), as well as newer markers, e.g., apolipoprotein B (apoB) and the ratio between apoB and apoA. Additionally, given the inflammatory nature of the development of atherosclerosis, high-sensitivity c-reactive protein (hs-CRP) or interleukin-6 (IL-6) are also discussed. Additionally, newer publications on other emerging components linked to atherosclerosis were considered in the context of patient evaluation. Apart from the already in-use markers (e.g., LDL-C), emerging research highlights the potential of newer molecules in optimizing the diagnosis of atherosclerotic disease in earlier stages. After further studies, they might be fully implemented in the screening protocols.

Serum growth differentiation factor-15 levels are associated with the severity of diabetic foot ulcer

AIMS

To assess serum growth differentiation factor-15 (GDF-15) levels in patients with diabetic foot ulcer and to reveal whether any association exists between GDF-15 and the severity of diabetic foot ulcer.

DESIGN

A cross-sectional study including three age- and sex-matched cohorts comprising 17 patients (7 F, mean age: 52 ± 7 years) with diabetic foot ulcer (DMf), 17 patients with type 2 diabetes (6 F, mean age: 51 ± 6 years) with no foot complication (DM), and 20 healthy controls (8 F, mean age: 50 ± 8 years) (C) was conducted.

RESULTS

DMf had higher GDF-15 levels, followed by DM and C (GDF-15, median ± IQR (pg/mL), DMf: 1039 (884-1566), DM: 649 (375-1148), and C: 296 (212-534), p < 0.001). The severity of diabetic foot disease was positively associated with serum GDF-15 (GDF-15, median ± IQR (pg/mL), Wagner grade 1: 893 (698-1039), Wagner grade 3: 1705 (1348-2197), and Wagner grade 4: 3075 (1974-4176), p for trend = 0.006). In multivariate regression model, only Wagner grade (β = 0.55, 95% CI (87-753), p = 0.02) was found to be an independent factor affecting serum GDF-15 concentration.

CONCLUSIONS

Serum GDF-15 levels are high in patients with diabetic foot ulcer. The level is higher in more advanced lesions. GDF-15 measurement can have clinical utility in the management of diabetic foot ulcers.

Association of GDF-15, hs-cTnT and NT-proBNP with coronary artery disease in patients undergoing elective angiography

Aim: This study investigated the association between plasma levels of GDF-15, hs-cTnT and NT-proBNP and the presence of coronary artery disease (CAD) in stable patients referred for elective coronary angiography. Methods: The outcome of CAD was defined as an ordinal variable with 3 levels. The association between each biomarker and the outcome was tested using the Winell and Lindbäck method. Results: In unadjusted analysis of 252 patients, GDF-15 and hs-cTnT were associated with the presence and extent of CAD. In multivariate regression analysis including traditional risk factors, this association was no longer significant. Conclusion: NT-proBNP, GDF-15 and hs-cTnT plasma levels do not seem to improve the predictive ability of traditional risk factors for CAD in stable patients referred for coronary angiography.

GDF-15, a future therapeutic target of glucolipid metabolic disorders and cardiovascular disease

Growth and differentiation factor 15 (GDF-15) was discovered as a member of the transforming growth factor β (TGF-β) superfamily and the serum level of GDF-15 was significantly correlated with glucolipid metabolic disorders (GLMD) and cardiovascular diseases. In 2017, a novel identified receptor of GDF-15-glial-derived neurotrophic factor receptor alpha-like (GFRAL) was found to regulate energy homeostasis (such as obesity, diabetes and non-alcoholic fatty liver disease (NAFLD)). The function of GDF-15/GFRAL in suppressing appetite, enhancing glucose/lipid metabolism and vascular remodeling has been gradually revealed. These effects make it a potential therapeutic target for GLMD and vascular diseases. In this narrative review, we included and reviewed 121 articles by screening 524 articles from literature database. We primarily focused on the function of GDF-15 and its role in GLMD/cardiovascular diseases and discuss its potential clinical application.

GDF-15 Suppresses Atherosclerosis by Inhibiting oxLDL-Induced Lipid Accumulation and Inflammation in Macrophages

The growth differentiation factor-15 (GDF-15) may be involved in atherosclerosis. However, the role of GDF-15 in atherosclerosis remains unclear. The main goal of this study was to verify the role and mechanism of GDF-15 in atherogenesis. We first compared the serum GDF-15 level between patients with coronary atherosclerosis and healthy people. And then one ApoE^-/- mouse model of atherosclerosis was used to explore the effects of GDF-15 on oxidized low-density lipoprotein (oxLDL) accumulation, atherosclerosis-related gene expression, and lipid accumulation-related protein expression in mouse macrophages. As a result, the level of serum GDF-15 in patients with coronary atherosclerosis was significantly higher than that in healthy people. In the mouse model, GDF-15 expression was elevated in the core of plaque, and it was secreted mainly by the macrophages. In addition, GDF-15 decreased oxLDL-induced lipid accumulation and inflammation activation in macrophages. GDF-15 decreased the mRNA expressions of CD36, LOX1, and TLR4 that are associated with lipoprotein accumulation in macrophages. Further study showed that GDF-15 might suppress oxLDL-induced lipoprotein accumulation via inhibiting CD36 and LOX1 and decrease inflammation in macrophages by inhibiting TLR4. Thus, GDF-15 may suppress atherosclerosis and plaque formation by inhibiting lipoprotein accumulation and inflammation activation.

Regular Dietary Intake of Palmitate Causes Vascular and Valvular Calcification in a Rabbit Model

Aims: Palmitic acid (PA) and oleic acid (OA) are two main dietary fatty acids. Dietary intake of PA has been associated with cardiovascular disease risk, and the effect of OA remains uncertain. Our study aimed to assess the effect of a short-term intake of lard, as source of PA and OA, on aorta and aortic valve.

Methods and Results: Rabbits were fed with two lard-enriched diets, containing either elevated levels of PA or of both PA and OA as compared to chow diet. After 16 weeks of each diet, calcification was observed in the aortic intima and in the aortic valve. The extent of calcification did not differ between the two diets. In contrast, rabbits fed chow diet did not develop any calcification. In blood, PA enrichment resulted in decreased lymphocyte and monocyte counts and increased levels of hemoglobin and haematocrit. Levels of the calcification inhibitor fetuin-A were also diminished, whereas creatinine levels were raised. Of note, none of the diets changed cholesterol levels in LDL or HDL. Comprehensive quantitative lipidomics analysis identified diet-related changes in plasma lipids. Dietary PA enrichment led to a drop of polyunsaturated fatty acids (PUFA), in particular of linoleic acid in cholesteryl esters, triglycerides and diacylglycerols (DAG). Ratios of PA to 18-carbon PUFA in DAG were positively correlated with the extent of aortic valve calcification, and inversely with monocyte counts. PA content in blood correlated with aorta calcification.

Conclusions: Regular dietary PA intake induces vascular and valvular calcification independently of traditional risk factors. Our findings raise awareness about PA-rich food consumption and its potential deleterious effect on cardiovascular health.

Prognostic Value of GDF-15 in Predicting Prolonged Intensive Care Stay following Cardiac Surgery: A Pilot Study

INTRODUCTION

Predicting intensive care unit length of stay and outcome following cardiac surgery is currently based on clinical parameters. Novel biomarkers could be employed to improve the prediction models.

MATERIALS AND METHODS

We performed a qualitative cytokine screening array to identify highly expressed biomarkers in preoperative blood samples of cardiac surgery patients. After identification of one highly expressed biomarker, growth differentiation factor 15 (GDF-15), a quantitative ELISA was undertaken. Preoperative levels of GDF-15 were compared in regard to duration of intensive care stay, cardiopulmonary bypass time, and indicators of organ dysfunction.

RESULTS

Preoperatively, GDF-15 was highly expressed in addition to several less highly expressed other biomarkers. After qualitative analysis, we could show that preoperatively raised levels of GDF-15 were positively associated with prolonged ICU stay exceeding 48 h (median 713 versus 1041 pg/ml, p = 0.003). It was also associated with prolonged mechanical ventilation and rates of severe sepsis but not with dialysis rates or cardiopulmonary bypass time. In univariate regression, raised GDF-15 levels were predictive of a prolonged ICU stay (OR 1.01, 95% confidence interval 1-1.02, and p = 0.029). On ROC curves, GDF-15 was found to predict prolonged ICU stay (AUC = 0.86, 95% confidence interval 0.71-0.99, and p = 0.003).

CONCLUSION

GDF-15 showed potential as predictor of prolonged intensive care stay following cardiac surgery, which might be valuable for risk stratification models.

Evaluation of Growth Differentiation Factor-15 in Patients with or without Coronary Artery Disease

Background:

Growth-differentiation factor-15 (GDF-15) is a distant member of the transforming growth factor-beta cytokine superfamily expressed in human atherosclerotic plaque macrophages. In this study, we sought to compare GDF-15 between patients with coronary artery disease and control group.

Methods:

In this cross-sectional study, 176 subjects were enrolled, consisted of 88 coronary artery disease patients (CAD group) and 88 non-CAD participants (control group. Clinical and demographic data, comprising of family history of CAD, history, and lifestyle factors, hypertension, diabetes, and some blood parameters (e.g. glucose, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C)), triglyceride, high-sensitivity C-reactive protein (hs-CRP)).

Results:

Mean age of the patients was 55.5±11.1 years (age range: 28–80 years). Of all the participants, 91 (51.7%) were male and 85 (48.3%) female. Hs-CRP, LDL-C, and GDF-15 levels were significantly higher in the CAD patients (P=0.091, P=0.008, and P<0.001, respectively). Total cholesterol, hematocrit, and hemoglobin were significantly higher in the controls (P=0.002, P=0.011, and P=0.055, respectively). The area under the receiver operating characteristic curve yielded the satisfactory result of 0.9 (95% CI, 0.8-0.9; P<0.001). The optimum cut-off value of GDF-15 was 1233 ng/L with 71% specificity and 71% sensitivity for CAD diagnosis.

Conclusion:

These data suggest that serum GDF-15 might be useful in prediction of CAD. (www.actabiomedica)

Growth differentiation factor-15 and its role in diabetes and cardiovascular disease

Growth differentiation factor-15 (GDF-15) is cytokine involved in the regulation of multiple systems. Because it has regularly been shown to be increased in cardiovascular disease (CVD) and diabetes, it has been suggested that GDF-15 could be used as a biomarker for these diseases and their severity. However, several studies have demonstrated that GDF-15 has a protective role in regulation of inflammation, endothelial cell function, insulin sensitivity, weight gain, and is cardioprotective in myocardial infarction (MI). While GDF-15 has been implicated in the pathophysiology of many conditions including cancer, this review focuses on the potential functions of GDF-15 and signaling pathways implicated in its role regulating metabolism, insulin sensitivity, and the cardiovascular system.

Alterations of Specific Lymphocytic Subsets with Aging and Age-Related Metabolic and Cardiovascular Diseases

To investigate the association of immunosenescence with aged-related morbidity in the elderly, a clinical study was conducted to analyze and compare the alterations in peripheral blood (PB) T-cell subsets among young healthy (YH) controls, elderly healthy (EH) controls, and age-matched elderly patients with metabolic diseases (E-MDs), with cardiovascular diseases (E-CVDs) or with both (E-MDs/E-CVDs). The frequencies of CD3T, CD8T and invariant natural killer T (iNKT) cells were decreased in the EH, E-MD and E-CVD cohorts, indicating a decline in defense function. Although CD4T and regulatory T (Treg) cell frequencies tended to increase with aging, they were lower in patients with E-MDs and E-CVDs. Subset analyses of T-cells consistently showed the accumulation of senescent T-cell in aging and in patients with E-MDs and E-CVDs, compared with YH volunteers. These accumulated senescent T-cells were undergoing apoptosis upon stimulation due to the replicative senescence stage of T-cells. In addition, serum levels of cytokines, including interferon (IF)-γ, transforming growth factor (TGF)-β and growth differentiation factor (GDF)-15, consistently reflected alterations in T-cell subsets. This study demonstrated that T-cell subset changes with paralleled alterations in cytokines were associated with aging and age-related pathogenesis. These altered T-cell subsets and/or cytokines can potentially serve as biomarkers for the prevention, diagnosis and treatment of age-related morbidities.

The Biomarkers for Acute Myocardial Infarction and Heart Failure

The use of a large number of cardiovascular biomarkers, meant to complement the use of the electrocardiogram, echocardiography cardiac imaging, and clinical symptom assessment, has become a routine in clinical diagnosis, differential diagnosis, risk stratification, and prognosis and guides the management of patients with suspected cardiovascular diseases. There is a broad consensus that cardiac troponin and natriuretic peptides are the preferred biomarkers in clinical practice for the diagnosis of the acute coronary syndrome and heart failure, respectively, while the roles and possible clinical applications of several other potential biomarkers are still under study. This review mainly focuses on the recent studies of the roles and clinical applications of troponin and natriuretic peptides, which seem to be the best-validated markers in distinguishing and predicting the future cardiac events of patients with suspected cardiovascular diseases. Additionally, the review briefly discusses some of the large number of potential markers that may play a more prominent role in the future.

Relationship of growth differentiation factor-15 with aortic stiffness in essential hypertension

Aim:

We aimed to assess the relationship between echocardiographic parameters of aortic elasticity, namely aortic strain, aortic distensibility and aortic β-index, and serum growth differentiation factor (GDF)-15 in patients with newly diagnosed essential hypertension (HT).

Methods:

Grade-1 HT patients (n = 50), grade-2 HT (n = 70) patients and 35 healthy controls were included.

Results:

GDF-15 was greater in grade-2 HT group compared with the other groups. All aortic elasticity parameters were worse in grade-2 HT group compared with the other groups. GDF-15 correlated positively with E/E′ ratio (the ratio of transmitral E velocity to mean diastolic mitral annular velocity) and β-index; and aortic strain and aortic distensibility correlated negatively with serum GDF-15. β-index, aortic diastolic diameter and diastolic blood pressure were independently associated with GDF-15.

Conclusion:

GDF-15 may be utilized in the prediction of increased aortic stiffness.

Hypertension is a leading cause of morbidity and mortality worldwide, and is closely associated with impaired arterial and aortic elasticity. Growth differentiation factor (GDF)-15 is a novel marker of cardiovascular diseases, and appeals more and more to the researchers. In the present study, we evaluated the relationship of GDF-15 with echocardiographic parameters regarding aortic stiffness, namely aortic β-index, aortic distensibility and aortic strain in 120 newly diagnosed hypertensive patients. We found that serum GDF-15 was correlated with impaired aortic elasticity; moreover, it turned out to be a potent predictor of an increased aortic β-index in hypertension.

Growth differentiation factor 15 (GDF15): A survival protein with therapeutic potential in metabolic diseases

Growth Differentiation Factor 15 (GDF15), also known as NSAID activated gene-1 (NAG-1), is associated with a large number of biological processes and diseases, including cancer and obesity. GDF15 is synthesized as pro-GDF15, is dimerized, and is cleaved and secreted into the circulation as a mature dimer GDF15. Both the intracellular GDF15 and the circulating mature GDF15 are implicated in biological processes, such as energy homeostasis and body weight regulation. Although there have been many studies on GDF15, GFRAL, a member of the glial-derived neurotropic factor receptor α family, has only been recently identified as a receptor for mature GDF15. In this review, we focused on cancer and energy homeostasis along with obesity and body weight, and the effect of the identification of the GDF15 receptor in these investigations. In addition, the therapeutic potential of GDF15 as a pharmacological agent in obesity and other metabolic diseases was discussed.

Association between Growth Differentiation Factor 15 and Non-Dipping Circadian Pattern in Patients with Newly Diagnosed Essential Hypertension

OBJECTIVE

Non-dipper hypertension (HT) confers greater risk compared with dipper HT. Growth differentiation factor 15 (GDF-15) recently emerged as a novel and independent marker of cardiovascular disease, both in diagnostic and prognostic scopes. Our aim was to evaluate the relationship of circadian blood pressure (BP) pattern with serum GDF-15 level in newly diagnosed HT patients without left ventricular hypertrophy.

SUBJECTS AND METHODS

Newly diagnosed non-dipper (n = 66) and dipper (n = 60) HT patients were selected according to 24-h ambulatory BP monitoring (ABPM). The controls comprised healthy normotensive subjects (n = 31). Data was collected through physical examination, laboratory analysis, ABPM, and echocardiography. GDF-15 was measured using ELISA.

RESULTS

Greater GDF-15 level was found in the non-dippers compared with the dippers and the controls (557.53 ± 91.7, 513.79 ± 62.86, and 494.44 ± 79.30 ng/L, respectively, p < 0.001). In bivariate linear correlation analysis, GDF-15 correlated positively with glomerular filtration rate (r = 0.180, p =0.030), total cholesterol (r = 0.170, p = 0.038), septal E/E' ratio (r = 0.344, p = 0.001), lateral E/E' ratio (r = 0.366, p < 0.001), nighttime systolic BP (r = 0.166, p = 0.046), and nighttime diastolic BP (r = 0.188, p = 0.024); however, it correlated negatively with septal and lateral E' velocities (r = 0.268, p = 0.005 and r = 0.236, p = 0.013, respectively). Furthermore, GDF-15 level and nighttime diastolic BP remained independently associated with non-dipper HT. In ROC analysis, optimal cutoff value for GDF-15 was 524.6 ng/L with 56.7% sensitivity and 72.4% specificity (AUC: 0.676, 95% CI: 0.580-0.772, p < 0.05).

CONCLUSION

Our results showed GDF-15 upregulation in the non-dipper HT group. GDF-15 and nighttime diastolic BP were independently associated with the non-dipping pattern. This study may suggest possible utilization of GDF-15 in the prediction of non-dipper HT.

Biomarkers in stable coronary artery disease

Coronary artery disease (CAD) remains a significant cause of morbidity and mortality around the world. Patients with stable CAD can have an unpredictable clinical trajectory; thus, additional tools to prognosticate risk in this cohort are warranted. In recent years, a wide range of biomarkers has been recognized for their diagnostic capabilities in patients with stable CAD, identifying those with obstructive disease who may require more intensive preventive therapies or even consideration of percutaneous coronary intervention in some circumstances. In addition, a multiple-biomarker approach may identify stable CAD patients at highest risk for future major adverse cardiac events. Thus, randomized controlled trials to assess biomarker-guided preventive therapy in this cohort appear warranted.

Expanded Haemodialysis Therapy of Chronic Haemodialysis Patients Prevents Calcification and Apoptosis of Vascular Smooth Muscle Cells in vitro

BACKGROUND

Vascular calcification is a common phenomenon in patients with chronic kidney disease and strongly associated with increased cardiovascular mortality. Vascular calcification is an active process mediated in part by inflammatory processes in vascular smooth muscle cells (VSMC). These could be modified by the insufficient removal of proinflammatory cytokines through conventional high-flux (HF) membranes. Recent trials demonstrated a reduction of inflammation in VSMC by use of dialysis membranes with a higher and steeper cut-off. These membranes caused significant albumin loss. Therefore, the effect of high retention Onset (HRO) dialysis membranes on vascular calcification and its implications in vitro was evaluated.

METHODS

In the PERCI II trial, 48 chronic dialysis patients were dialyzed using HF and HRO dialyzers and serum samples were collected. Calcifying VSMC were incubated with the serum samples. Calcification was determined using alizarin red staining (AZR) and determination of alkaline phosphatase (ALP) activity. Furthermore, apoptosis was evaluated, and release of matrix Gla protein (MGP), osteopontin (OPN) and growth differentiation factor 15 (GDF-15) were measured in cell supernatants.

RESULTS

Vascular calcification in vitro was significantly reduced by 24% (ALP) and 36% (AZR) after 4 weeks of HRO dialysis and by 33% (ALP) and 48% (AZR) after 12 weeks of dialysis using HRO membranes compared to HF dialysis. Apoptosis was significantly lower in the HRO group. The concentrations of MGP and OPN were significantly elevated after incubation with HF serum compared to HRO serum and healthy controls. Similarly, GDF-15 release in the supernatant was elevated after incubation with HF serum, an effect significantly ameliorated after treatment with HRO medium.

CONCLUSIONS

Expanded haemodialysis therapy reduces the pro-calcific potential of serum from dialysis patients in vitro. With a markedly reduced albumin filtration compared to high cut-off dialysis, use of the HRO dialyzers may possibly provide a treatment option for chronic dialysis patients to reduce the progression of vascular calcification.

Serum Growth Differentiation Factor 15 in Parkinson Disease

BACKGROUND

Growth differentiation factor 15 (GDF15) has been shown to be protective for dopaminergic neurons in animal and ex vivo experiments. However, little is known about its effect on the human body.

OBJECTIVE

This study investigated associations between serum GDF15 levels and clinical parameters in patients with Parkinson disease (PD).

METHODS

Idiopathic PD patients (n = 104) and age-matched controls (n = 88) were enrolled. Serum GDF15 levels were measured by human enzyme-linked immunosorbent assay. Univariate and multivariate analyses investigated correlations between GDF15 and clinical characteristics, including disease severity by the Unified PD Rating Scale (UPDRS)-III. The diagnostic value of GDF15 was evaluated by receiver-operating characteristic curve (ROC) analysis.

RESULTS

The serum GDF15 levels of the PD patients were significantly higher than those of the healthy controls. In PD patients, serum GDF15 levels in men were significantly higher than in women. GDF15 levels correlated with age, gender, disease duration, and UPDRS-III score. After adjusting for confounding factors, multiple linear regression analysis showed that the serum GDF15 level (β = 0.015, p = 0.001) was an independent risk factor for UPDRS-III score. In ROC analysis, GDF15 achieved an area under the curve of 0.86 for the identification of PD, with a sensitivity of 71.15% and a specificity of 87.50%.

CONCLUSION

GDF15 may be a potential biomarker for the diagnosis and monitoring of motor severity in PD.