Unbound Free Fatty Acids and Heart-Type Fatty Acid–Binding Protein: Diagnostic Assays and Clinical Applications

Novel Biomarkers in Early Detection of Heart Failure: A Narrative Review

Heart failure (HF) represents a significant global health challenge, characterized by a variety of symptoms resulting from cardiac dysfunction. This dysfunction often leads to systemic and pulmonary congestion. The pathophysiology of HF is complex, involving stimulation of the sympathetic nervous system, which is insufficiently balanced by the release of natriuretic peptide. This imbalance leads to progressive hypertrophy and dilatation of the heart's chambers, impairing its pumping efficiency and increasing the risk of arrhythmias and conduction disorders. The prevalence of HF is exceptionally high in industrialized nations and is expected to increase owing to an aging population and advancements in diagnostic methods. This study emphasizes the critical role of early diagnosis in reducing morbidity and mortality associated with HF, focusing specifically on the evolving importance of biomarkers in managing this condition. Biomarkers have played a key role in transforming the diagnosis and treatment of HF. Traditional biomarkers such as b-type natriuretic peptide and N-terminal pro-b-type natriuretic peptide have been widely adopted for their cost-effectiveness and ease of access. However, the rise of novel biomarkers such as growth differentiation factor 15 and adrenomedullin has shown promising results, offering superior sensitivity and specificity. These new biomarkers enhance diagnostic accuracy, risk stratification, and prognostic evaluation in HF patients. Despite these advancements, challenges remain, such as limited availability, high costs, and the need for further validation in diverse patient populations. Through a comprehensive literature review across databases such as PubMed, Google Scholar, and the Cochrane Library, this study compiles and analyzes data from 18 relevant studies, offering a detailed understanding of the current state of HF biomarkers. The study examines both traditional and emerging biomarkers such as galectin-3 and soluble suppression of tumorigenicity 2 in HF, exploring their clinical roles and impact on patient outcomes.

The impact of the administration of red ginseng (Panax ginseng) on lipid metabolism and free fatty acid profiles in healthy horses using a molecular networking approach

This study investigated the potential benefits of the administration of red ginseng (RG) on lipid metabolism and the profiles of individual free fatty acids (FFAs) in healthy horses. Eight healthy horses, raised under similar conditions, were randomly divided into two groups, each comprising four horses. The experimental group received powdered RG (600 mg/kg/day) mixed with a carrier, and the control group received only the carrier. The parameters associated with lipid metabolism and probable adverse effects were evaluated in both groups after 3 weeks. The computational molecular networking (MN) approach was applied to analyze the FFA profiles. The results indicated that RG administration significantly reduced blood triglyceride levels in the experimental group. Analysis of the FFAs using MN revealed significant decreases in specific types of FFAs (C12:0, dodecanoic acid; C14:0, myristric acid; C18:1, oleic acid; C18:2, linoleic acid). RG consumption did not produce significant adverse effects on the renal, hepatic, and immune functions. Thus, RG was found to effectively modulate lipid metabolism and the levels of individual FFAs. The application of the MN for the analysis of FFAs represents a novel approach and can be considered for future research.

Evaluation of novel biomarkers for early diagnosis of bisphenol A-induced coronary artery disease

Introduction

Bisphenol A (BPA), a ubiquitous synthetic monomer primarily used in the manufacture of polycarbonate plastic and epoxy resins and as a non-polymer additive to other plastics, can leach into the food and water supply and has been linked to cardiovascular disease (CVD). This study aimed to analyze BPA levels in patients with varying numbers of coronary artery stenosis and evaluate the prognostic value of new biomarkers cluster of differentiation 36 (CD36) and heart-type fatty acid-binding protein (H-FABP), compared to troponin I and creatine kinase (CK) MB, for detecting myocardial injury.

Method

Eighty nine patients undergoing angiography at Urmia Hospital from March 2019 to 2020 were included. Serum levels of BPA, CD36, H-FABP, troponin I, and CK-M were measured.

Results

When comparing CD36 and H-FABP with troponin I and CK-MB across coronary occlusion classes, receiver operating characteristic curves indicated CD36 and H-FABP had higher accuracy than troponin I and CK-MB for detecting stenosis stages. In patients with occlusion, significant alterations were detected in age, sex, BMI, hypertension, diabetes, dyslipidemia, and smoking. BPA serum concentration significantly increased compared to normal subjects.

Conclusions

Our study revealed that serum biomarkers were valuable for prognosticating myocardial injury. Among these, CD36 and H-FABP were more accurate. BPA concentration correlated with myocardial necrosis, underlying disease, and occlusion stage, suggesting BPA's harmful effects.

Birth size, growth trajectory and later cardio-metabolic risk

There is increasing evidence of a strong association between intrauterine growth and subsequent development of chronic disease in adult life. Birth size and growth trajectory have been demonstrated to have an impact on cardio-metabolic health, both in childhood and adult life. Hence, careful observation of the children's growth pattern, starting from the intrauterine period and the first years of life, should be emphasized to detect the possible onset of cardio-metabolic sequelae. This allows to intervene on them as soon as they are detected, first of all through lifestyle interventions, whose efficacy seems to be higher when they are started early. Recent papers suggest that prematurity may constitute an independent risk factor for the development of cardiovascular disease and metabolic syndrome, regardless of birth weight. The purpose of the present review is to examine and summarize the available knowledge about the dynamic association between intrauterine and postnatal growth and cardio-metabolic risk, from childhood to adulthood.

Admission free-fatty acid level is a predictor of the mid-term worsening renal function in patients with ST-segment elevation myocardial infarction

Whether free fatty acids (FFAs), which are generators of reactive oxygen species and substrates of cytotoxic lipid peroxidation products in proximal tubules of the kidney, can be a predictor of worsening renal function (WRF) is not fully elucidated. A total of 110 patients with ST-segment elevation myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention within 24 h after symptom onset were included. The exclusion criteria were out-of-hospital cardiac arrest, vasospastic angina, hemodialysis, and/or lack of data. FFAs and serum cystatin C were measured on admission, and urinary liver-type fatty acid-binding protein (L-FABP) was measured 3 h after admission. WRF, defined as an increase in serum creatinine by ≥ 0.3 mg/dL for 2-year follow-up, was observed in 16 patients (15%). A multivariate logistic regression analysis (a stepwise algorithm) revealed that the FFA level was an independent predictor of WRF (P = 0.024). The FFA level was associated with WRF adjusted after serum cystatin C (odds ratio [OR]: 1.378 per 1 mEq/L, P = 0.017), L-FABP (OR: 1.370 per 1 mEq/L, P = 0.016), or the Mehran contrast-induced nephropathy (CIN) risk score (OR: 1.362 per 1 mEq/L, P = 0.021). The FFA level was inversely associated with the change in estimated glomerular filtration rate level for 2 years (R² = 0.051, P = 0.018). The FFA level on admission was associated with the mid-term WRF in patients with STEMI.

The relationships between serum heart-type fatty acid-binding protein and right ventricular echocardiographic indices in chronic obstructive pulmonary disease

BACKGROUND

Heart-type Fatty Acid-Binding Protein (H-FABP) has been used in the diagnosis of myocardial damage. In this study, we assessed the relationships between serum H-FABP as a marker of cardiac injury and right ventricle (RV) echocardiographic indices in patients with stable COPD.

MATERIALS AND METHODS

In this case-control study, 84 participants were investigated (50 COPD patients and 34 healthy subjects). After obtaining consent, 3 mL of fasting whole blood sample was collected from each of the participants to test their serum H-FABP. Echocardiography was performed on all participants by cardiologists.

RESULTS

Serum H-FABP was found to be significantly correlated with smoking history (P < 0.01), Systolic Pulmonary Artery Pressure (S-PAP), RV Wall Thickness (RV-WT), and Tricuspid annulus posts systolic excursion (TAPSE) (P < 0.01 for all). RV Basal Diameter (RV-BD), RV Mid Diameter (RV-MD), and Fractional area change percentage (FAC%) were not observed to have any correlation with serum H-FABP. Also, the comparative analysis showed statistically significant differences between mean RV-MD (P < 0.001), RV-BD, FAC%, S-PAP, RV-WT (P < 0.001), and TAPSE (P < 0.05) of patients at different GOLD stages. There was a significant correlation between the adjusted serum level of H-FABP and the airflow limitation based on FEV1 (P < 0.001).

CONCLUSION

The correlation between serum H-FABP and RV echocardiographic indices such as S-PAP, RV-WT, and TAPSE, can be related to RV function in COPD patients. Moreover, RV echocardiographic indices are significantly correlated with the severity of COPD as classified in various GOLD stages.

Prognostic value of prealbumin, N-terminal pro-B-type natriuretic peptide, heart type fatty acid binding protein, and cardiac troponin I in elderly patients for heart failure and poor outcomes

Objectives

This study aimed to investigate the prognostic value of serum prealbumin, N-terminal pro-B-type natriuretic peptide (NT-proBNP), heart type fatty acid binding protein (hFABP), and cardiac troponin I (cTnI) for heart failure and cardiac death in elderly patients.

Methods

We studied 426 consecutive patients with New York Heart Association classes I to IV who were recruited between February 2014 and 2018. Cardiac mortality was the primary end point. Receiver operator characteristic curves were created to analyze predictive values.

Results

When prealbumin, NT-proBNP, hFABP, and cTnI were combined, the areas under the receiver operator characteristic curve reached 0.930 and 0.903 for heart failure and cardiac death, respectively. Prealbumin, NT-proBNP, hFABP, and cTnI levels changed differently during therapy in patients in different prognosis groups. These parameters improved in patients who did not develop major adverse cardiovascular events (MACEs), but were unchanged or deteriorated in patients with MACEs. Multivariate Cox regression analysis showed that these parameters were significant independent risk factors for MACEs and cardiac death.

Conclusions

Our study shows that serum prealbumin, NT-proBNP, hFABP, and cTnI levels are significant prognostic factors for elderly patients with poor cardiac function. These parameters are more accurate for prognosis when used together.

Simultaneous detection of diethylstilbestrol and estradiol residues with a single immunochromatographic assay strip

An immunochromatographic assay (ICA) based on competitive format was developed and validated for simultaneously rapid and sensitive detection of diethylstilbestrol (DES) and estradiol (E2) in milk and tissue samples. For this purpose, two monoclonal antibodies raised against those two estrogens were conjugated to gold nanoparticles and were applied to the conjugate pads of the test strip. The competitors of the DES-BSA/E2-BSA conjugates were immobilized onto a nitrocellulose membrane at two detection zones to form T1 and T2, respectively. The immunochromatographic assay had a visual detection limit of DES at 30 ng/g in milk powder, 25 ng/g in liquid milk, and 25 ng/g in shrimp tissue, respectively, and the results can be judged within 7-10 min. The visual detection limit of E2 was 75 ng/g in milk powder, 65 ng/g in liquid milk, and 60 ng/g in shrimp tissue, respectively, and the results can be judged within 3-4 min. It had advantages in easy operation without requiring sophisticated equipment and specialized skills. By testing thirty milk and shrimp tissue samples from the local market, the method was compared with the HPLC-MS / MS method, and there was no statistical difference between the two methods. Furthermore, the immunochromatographic assay had good specificity, simple procedure, and low cost. This protocol was well suited for the food safety monitoring and early warning.

SERS-based magnetic immunoassay for simultaneous detection of cTnI and H-FABP using core-shell nanotags

Acute myocardial infarction (AMI) is the single leading cause of worldwide mortality and morbidity. Heart-type fatty acid-binding protein (H-FABP) and cardiac troponin I (cTnI), as biomarkers emerging at different stages of AMI, have complementary advantages in terms of specificity and sensitivity. Therefore, we developed a magnetic immunoassay method based on surface-enhanced Raman scattering (SERS) to detect H-FABP and cTnI simultaneously. Herein, two mutually independent Raman reporter molecules were embedded between a gold core and silver shell and then combined with a tracer antibody to form a SERS immunoprobe. During detection, the SERS immunoprobe, target antigen and capture probe undergo an immune reaction to form a sandwich structure, and then the immune complex was enriched by a specific reaction of streptavidin on the surface of magnetic beads with biotin. Finally, the concentration of biomarkers was quantified by detecting the characteristic Raman peak intensities of the two Raman reporter molecules. Under the optimized conditions, the minimum detection limits of H-FABP and cTnI were 0.6396 and 0.0044 ng mL^-1, respectively. Besides, the target antigen does not cross-react with non-specific proteins, showing good specificity. Therefore, our proposed SERS-based magnetic immunoassay method has the advantages of accuracy, rapidity and good selectivity, and has great potential for early diagnosis of acute myocardial infarction disease.

Determination of carcinoembryonic antigen as a tumor marker using a novel graphene-based label-free electrochemical immunosensor

In this work, a simple label-free electrochemical immunosensor for the detection of carcinoembryonic antigen (CEA) was developed. At first, the GC electrode was coated with partially reduced graphene oxide (rGO) to form a platform to bind the antibody. After activating the carboxyl groups of rGO through the EDC/NHS linker, the electrode surface was covered with the antibody. Then, the electrochemical behavior of the antibody-modified electrode and the parameters of the interactions of antibody-antigen immune complexes were investigated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). This immune-complex layer was found to attenuate the electrochemical current which can be used as a good signal to determine the antigen concentration. The proposed immunosensor exhibited a good amperometric response to CEA within a concentration range of 0.1-5 ng mL^-1 with a detection limit of 0.05 ng ml^-1. Furthermore, the developed method was evaluated for the detection of CEA in the real sample (human blood serum), and the results were comparable with the reference values obtained by the standard enzyme-linked immunosorbent assay (ELISA). Our findings suggest the present immunosensor as a good candidate for application in clinical screening.

H-FABP: A beacon of hope for prediabetic heart disease

Background:

Prediabetes is increasingly being studied in the context of its association with cardiovascular disease (CVD). Besides raised HbA1c and sugar levels, the major underlying defect seems to be insulin resistance (IR). Subclinical atherosclerosis, measured by high sensitivity C reactive protein (hsCRP) and carotid artery intima media thickness (CIMT) underlies the pathogenesis of CVD in prediabetes. Heart-type fatty acid binding protein (H-FABP), a novel cardiac biomarker also might have a role in predictin prediabetic heart disease.

Aims:

The aim of the study is to compare serum levels of H-FABP in prediabetics and controls and correlate them with the atherosclerotic markers, hsCRP and CIMT.

Setting and Design:

50 prediabetic patients and 50 age, sex and BMI matched controls were employed in the case control study. Serum F & PPBS, (HbA1c), fasting insulin levels were measured in cases and controls. Serum H-FABP was measured in both cases and controls. All cases and controls were subjected to bilateral CIMT measurements and Serum hsCRP levels. The values were compared between both the groups and subjected to appropriate statistical analysis.

Statistical Analysis Used:

Categorical variables were presented in number and percentage (%) and continuous variables were presented as mean ± SD and median. Normality of data was tested by Kolmogorov-Smirnov test. If the normality was rejected then non parametric test was used. Quantitative variables were compared using Independent t test/Mann-Whitney Test (when the data sets were not normally distributed) between the two groups. Qualitative variables were correlated using Chi-Square test/Fisher's Exact test. Spearman rank correlation coefficient was used to find out the correlation of various parameters with each other. Univariate linear regression was used to find out the cause and effect relationship between various parameters. A p <0.05 was considered statistically significant. The data analysis was done using Statistical Package for Social Sciences (SPSS) version 21.0.

Results:

The mean serum levels of H-FABP among cases and controls were 6.38± 2.76ng/ml and 3.24 ± 2.47 ng/ml respectively (p <0.0001). Mean CIMT was found to be higher in prediabetics (0.59 ± 0.11 mm ) compared to controls (0.45 ± 0.07mm) (p<0.0001). Serum hsCRP levels were also statistically higher in prediabetics (5.75± 4.16 mg/l) then that of controls (1.86± 1.67 mg/l) (p <0.0001). The correlations of the two variables, hsCRP and CIMT with H-FABP were both strongly positive (r = 0.687) & (r = 0.779) respectively [both cases (p < 0.0001)].

Conclusion:

The novel cardiac biomarker H-FAPB might be a good predictor of cardiovascular risks in prediabetics.

Evaluation of the cardioprotective effects of crystalloid del Nido cardioplegia solution via a rapid and accurate cardiac marker: heart-type fatty acid-binding protein

Background/aim

Our aim in this study was to compare the efficacy and safety of crystalloid del Nido solution and cold blood cardioplegia solution on clinical and laboratory parameters.

Materials and methods

Sixty patients who underwent elective coronary bypass operation between July 2019 and January 2020 were included in our study. Patients were divided into 2 groups of 30 patients using del Nido solution (DNS) and cold blood cardioplegia solution (CBCS), which were given for cardiac arrest. Demographic data, preoperative, postoperative 0th h, 6th h and 4th day creatine kinase myocardial band (CK-MB) and troponin I values were compared with a specific cardiac enzyme heart-type fatty acid-binding protein (H-FABP).

Results

We found that aortic cross clamp duration and cardiopulmonary bypass (CPB) time were shorter in patients using del Nido solution than cold blood cardioplegia solution (57.30 ± 23.57 min, 76.07 ± 27.18 min, P = 0.006) (95.07 ± 23.06 min, 114.13 ± 33.93, P = 0.014). Total cardioplegia solution volume was higher in the cold blood cardioplegia solution group (1426.67 ± 416.00 vs. 1200 ± 310.73 P = 0.02). Preoperative and postoperative levels of cardiac enzymes including CK-MB, troponin I and H-FABP were comparable in del Nido solution and cold blood cardioplegia solution groups.

Conclusion

According to these results, when we compare both demographic data and CK-MB, troponin I and H-FABP levels, both cardioplegia solutions were comparable regarding safety and efficacy in terms of myocardial protection.

Biomarkers in diagnosing and treatment of acute heart failure

Acute heart failure (AHF) is a complex disorder involving different pathophysiological pathways. In recent years, there is an increased focus on biomarkers that help with diagnosis, risk stratification and disease monitoring of AHF. Finding a reliable set of biomarkers not only improves morbidity and mortality but it can also potentially reveal the new targets of therapy. In this paper, we have reviewed the biomarkers found useful for the diagnosis as well as for risk stratification and prognostication in patients with AHF. We have discussed the established biomarkers for AHF including cardiac troponins and natriuretic peptides and emerging biomarkers including adiponectin, mi-RNA, sST2, Gal-3, MR-proADM, OPG, CT-proAVP and H-FABP for the purposes of making diagnosis, their use as a guide of therapy or for determination of prognosis.

Chemiluminescence Immunoassays for Simultaneous Detection of Three Heart Disease Biomarkers Using Magnetic Carbon Composites and Three-Dimensional Microfluidic Paper-Based Device

Chemiluminescence (CL) immunoassays for simultaneous detection of early acute myocardial infarction (AMI) biomarkers, including copeptin, heart-type fatty acid binding protein (h-FABP), and cardiac troponin I (cTnI), were developed by using Co²⁺/N-(aminobutyl)-N-(ethylisoluminol) (ABEI) functionalized magnetic carbon composite (Co²⁺-ABEI-Fe₃O₄@void@C) as an interface and a three-dimensional microfluidic paper-based device (3D μPAD) as a detection system. For CL immunoassays, Co²⁺-ABEI-Fe₃O₄@void@C was assembled with chitosan (CS) and gold nanoparticle-conjugated antibody (Au-Ab) sequentially to form the sensing platform (Co²⁺-ABEI-Fe₃O₄@void@C-CS/Au-Ab). In the presence of antigen (Ag), Ag was captured by the sensing interface to form an immunocomplex, leading to an increase in CL intensity due to the catalysis of -COO^- existing in Ag. A 3D μPAD with three detection zones for simultaneous detection of copeptin, h-FABP, and cTnI was designed and fabricated to obtain time-resolved CL signals. Three kinds of immunocomplexes formed with copeptin, h-FABP, and cTnI were added to three detection zones of 3D μPAD, respectively. After injecting H₂O₂, three time-resolved CL signals were generated in one CL detection run by virtue of time-delayed transport of H₂O₂ to different detection zones. The three time-resolved CL signals were used for the simultaneous determination of copeptin, h-FABP, and cTnI. The detection limit of copeptin, h-FABP, and cTnI was 0.40 pg/mL, 0.32 pg/mL, and 0.50 pg/mL, respectively, which is at least 1 order of magnitude lower than most of the reported immunoassays. The immunoassays could be directly used for the detection of copeptin, h-FABP, and cTnI in human serum samples. The proposed immunoassays are simple, fast, sensitive, and selective, and are of great application potential in early diagnosis and treatment of AMI.

Blood Biomarkers for Traumatic Brain Injury: A Quantitative Assessment of Diagnostic and Prognostic Accuracy

Blood biomarkers have been explored for their potential to provide objective measures in the assessment of traumatic brain injury (TBI). However, it is not clear which biomarkers are best for diagnosis and prognosis in different severities of TBI. Here, we compare existing studies on the discriminative abilities of serum biomarkers for four commonly studied clinical situations: detecting concussion, predicting intracranial damage after mild TBI (mTBI), predicting delayed recovery after mTBI, and predicting adverse outcome after severe TBI (sTBI). We conducted a literature search of publications on biomarkers in TBI published up until July 2018. Operating characteristics were pooled for each biomarker for comparison. For detecting concussion, 4 biomarker panels and creatine kinase B type had excellent discriminative ability. For detecting intracranial injury and the need for a head CT scan after mTBI, 2 biomarker panels, and hyperphosphorylated tau had excellent operating characteristics. For predicting delayed recovery after mTBI, top candidates included calpain-derived αII-spectrin N-terminal fragment, tau A, neurofilament light, and ghrelin. For predicting adverse outcome following sTBI, no biomarker had excellent performance, but several had good performance, including markers of coagulation and inflammation, structural proteins in the brain, and proteins involved in homeostasis. The highest-performing biomarkers in each of these categories may provide insight into the pathophysiologies underlying mild and severe TBI. With further study, these biomarkers have the potential to be used alongside clinical and radiological data to improve TBI diagnostics, prognostics, and evidence-based medical management.

The sequence of prenatal growth restraint and postnatal catch-up growth: normal heart but thicker intima-media and more pre-peritoneal fat in late infancy

BACKGROUND

The sequence of prenatal growth restraint and postnatal catch-up growth leads to a thicker intima-media and more pre-peritoneal fat by age 3-6 years.

OBJECTIVES

To study whether carotid intima-media thickness (cIMT) and pre-peritoneal fat differ already between catch-up small-for-gestational-age (SGA) infants and appropriate-for-gestational-age (AGA) controls in late infancy (ages 1 and 2 years) and whether such differences - if any - are accompanied by differences in cardiac morphology and function.

METHODS

Longitudinal assessments included body height and weight; fasting glucose, insulin, Insulin-like growth factor (IGF-I), high-molecular-weight adiponectin; body composition (by absorptiometry); cIMT, aortic IMT, pre-peritoneal fat partitioning (by ultrasound); cardiac morphometry and function (by echocardiography) in AGA and SGA infants at birth, at age 1 year (N = 87), and again at age 2 years (N = 68).

RESULTS

Catch-up SGA infants had already a thicker cIMT than AGA controls at ages 1 and 2 years, and more pre-peritoneal fat by age 2 years (all p values between <0.01 and <0.0001); all cardiac and endocrine-metabolic results were similar in AGA and SGA infants at ages 1 and 2 years.

CONCLUSIONS

From late infancy onwards, catch-up SGA infants have a thicker cIMT and more pre-peritoneal fat than AGA controls, but their cardiac morphology and function remain reassuringly similar.

Worsening renal failure in patients with acute heart failure: the importance of cardiac biomarkers

Aims

The importance of true worsening renal failure (WRF), which is associated with a poor prognosis, had been suggested in patients with acute heart failure (AHF). The aim of the present study was to establish the biomarker strategy for the prediction of true WRF in AHF.

Methods and results

Two hundred eighty‐one patients with AHF were analysed. Their biomarkers were measured within 30 min of admission. Patients were assigned to the non‐WRF (n = 168), pseudo‐WRF (n = 56), or true‐WRF (n = 57) groups using the criteria of both acute kidney injury on admission and increasing serum creatinine value during the first 7 days. A Kaplan–Meier curve showed that the survival and heart failure event rate of the true‐WRF group within 1000 days was significantly lower than that of the non‐WRF and pseudo‐WRF groups (P ≤ 0.001). The multivariate Cox regression model also indicated that true WRF was an independent predictor of 1000 day mortality and heart failure events [hazard ratio: 4.315, 95% confidence interval (CI): 2.466–7.550, P ≤ 0.001, and hazard ratio: 2.834, 95% CI: 1.893–4.243, P ≤ 0.001, respectively]. The serum heart‐type fatty acid‐binding protein (s‐HFABP) levels were significantly higher in the true‐WRF group than in the non‐WRF and pseudo‐WRF groups (P ≤ 0.001). The multivariate logistic regression model indicated that the predictive biomarker for the true‐WRF group was the s‐HFABP level (odds ratio: 5.472, 95% CI: 2.729–10.972, P ≤ 0.001). The sensitivity and specificity for indicating the presence of true WRF were 73.7% and 76.8% (area under the curve = 0.831) for s‐HFABP in whole patients, respectively, and 94.7% and 72.7% (area under the curve = 0.904) in non‐chronic kidney disease (CKD) patients, respectively.

Conclusions

Cardiac biomarkers, especially the s‐HFABP, might predict the development of true WRF in AHF patients. Furthermore, the predictive value was higher in AHF patients without CKD than in those with CKD.

Comparison between creatine kinase MB, heart-type fatty acid-binding protein, and cardiac troponin T for detecting myocardial ischemic injury after cardiac surgery

BACKGROUND

Heart-type fatty acid-binding protein (H-FABP) is a cytoplasmic protein and is released form necrotic cardiac myocytes, as well as ischemic cardiac myocytes. In this study, we compared creatine kinase MB (CK-MB), H-FABP, and cardiac troponin T (cTnT) after coronary artery bypass grafting (CABG), heart valve surgery, or septal defect surgery to evaluate the difference in detecting myocardial injury between three markers.

METHODS

A total of 69 patients (CABG, 32; valve surgery, 27; and septal defect surgery, 10) were prospectively enrolled. Blood samples were taken at specific intervals.

RESULTS

Mean amount (AUC_0-72h) of CK-MB and cTnT released for 72 h in the patients with valve surgery were 2446 h·ng/ml and 93.2 h·ng/ml, which were significantly larger than those in the patients with CABG or septal defect surgery (p < .05). Mean amount (AUC_0-72h) of H-FABP released for 72 h in the patients with CABG was 1939 h·ng/ml, which was significantly larger than that in the patients with septal defect surgery (700.1 h·ng/ml) (p < .05).

CONCLUSION

H-FABP would be a more useful marker for detecting myocardial ischemic injury than CK-MB and cTnT. CK-MB and cTnT would be more sensitive to myocardial injury with surgical trauma than with ischemic injury in the patients with cardiac surgery.

Heart-Type Fatty Acid Binding Protein Level as a Tool in Identification of Early Cardiac Effects of Diabetic Ketoacidosis

OBJECTIVE

This study aimed to measure the serum levels of heart-type fatty acid binding protein (H-FABP) in patients presenting with diabetic ketoacidosis (DKA) and diabetic ketosis (DK) and to determine its role in identifying early-period cardiac ischemia.

METHODS

This prospective study included 35 patients diagnosed with DKA, 20 patients diagnosed with DK, and 20 control subjects. H-FABP, creatine kinase-MB (CK-MB), and troponin I levels were investigated at presentation in patients with DKA and DK and in the control group. H-FABP values were measured again after acidosis correction in the DKA patients.

RESULTS

No statistically significant differences were found with respect to troponin I and CK-MB within the groups. The H-FABP values of DKA patients at presentation were found to be significantly higher than those of DK patients and the control group (p=0.015). The H-FABP value of the DKA group was also found to be significantly higher than the value at hour 36 after acidosis correction (p=0.0001).

CONCLUSION

We would like to propose H-FABP as a potential marker for indicating myocardial ischemia.

The Pancreatic β-Cell: A Bioenergetic Perspective

The pancreatic β-cell secretes insulin in response to elevated plasma glucose. This review applies an external bioenergetic critique to the central processes of glucose-stimulated insulin secretion, including glycolytic and mitochondrial metabolism, the cytosolic adenine nucleotide pool, and its interaction with plasma membrane ion channels. The control mechanisms responsible for the unique responsiveness of the cell to glucose availability are discussed from bioenergetic and metabolic control standpoints. The concept of coupling factor facilitation of secretion is critiqued, and an attempt is made to unravel the bioenergetic basis of the oscillatory mechanisms controlling secretion. The need to consider the physiological constraints operating in the intact cell is emphasized throughout. The aim is to provide a coherent pathway through an extensive, complex, and sometimes bewildering literature, particularly for those unfamiliar with the field.

The use of biomarkers in detecting subclinical cardiotoxicity in doxorubicin-based treatment for paediatric patients with acute lymphoblastic leukaemia

The international standard protocol for acute lymphoblastic leukaemia (ALL), the most common haemato-oncological pathology at paediatric age, uses anthracyclines as antitumor agents, potentially associated with early or late onset cardiac damage. Currently, echocardiography is the gold standard in the diagnosis of cardiotoxicity, but several biomarkers are evaluated as a possible replacement, pending more extensive clinical studies. We started a prospective study in order to determine the role of two biomarkers, troponin and heart-type fatty acid binding protein, in the evaluation of cardiotoxicity in children over one year of age, diagnosed with ALL. Between February 2015 and April 2016, 20 patients were enrolled and monitored at diagnosis, during chemotherapy and four months after the end of reinduction, through cardiac evaluation and dosing of those two markers in five different points of the treatment protocol. During the first year of follow-up, the patients did not develop clinical signs of cardiac damage, but the study showed a slight increase in troponin levels during chemotherapy, with the return to baseline value after treatment cessation, and also a correlation with the total dose of anthracyclines given to the patient. On the other hand, the second biomarker, heart-type fatty acid binding protein, did not seem to be useful in detecting subclinical cardiac damage in these patients.

Key Questions for Translation of FFA Receptors: From Pharmacology to Medicines

The identification of fatty acids as ligands for the G-protein coupled free fatty acid (FFA) receptor family over 10 years ago led to intensive chemistry efforts to find small-molecule ligands for this class of receptors. Identification of potent, selective modulators of the FFA receptors and their utility in medicine has proven challenging, in part due to their complex pharmacology. Nevertheless, ligands have been identified that are sufficient for exploring the therapeutic potential of this class of receptors in rodents and, in the case of FFA1, FFA2, FFA4, and GPR84, also in humans. Expression profiling, the phenotyping of FFA receptor knockout mice, and the results of studies exploring the effects of these ligands in rodents have uncovered a number of indications where engagement of one or a combination of FFA receptors might provide some clinical benefit in areas including diabetes, inflammatory bowel syndrome, Alzheimer's, pain, and cancer. In this chapter, we will review the clinical potential of modulating FFA receptors based on preclinical and in some cases clinical studies with synthetic ligands. In particular, key aspects and challenges associated with small-molecule ligand identification and FFA receptor pharmacology will be addressed with a view of the hurdles that need to be overcome to fully understand the potential of the receptors as therapeutic targets.

Evidence for Acute Myocardial and Skeletal Muscle Injury after Serial Transthoracic Shocks in Healthy Swine

Background

Previous serological studies have shown controversial results whether defibrillation or cardioversion can cause myocardial injury. Cardiovascular Magnetic Resonance (CMR) can be used to detect myocardial edema, hyperemia and capillary leak as features of acute myocardial injury. The aim of this study was to assess for myocardial and skeletal muscle injury in swine following transthoracic shocks.

Methods

Seventeen anaesthetized swine were examined, with 11 undergoing five synchronized transthoracic shocks (200J). Myocardial and skeletal muscle injury were assessed at baseline and up to 5h post-shock employing T1 mapping, T2 mapping, early and late gadolinium enhancement. Serologic markers (cFABP, TnI, CK, and CK-MB) and myocardial tissue were assessed by standard histology methods.

Results

In myocardial regions within the shock path, T1 and T2 were significantly increased compared to remote myocardium in the same animals. The early gadolinium enhancement ratio between the left-ventricular myocardium and the right pectoral muscle was also increased compared to control animals. After the shocks cFABP and CK were significantly elevated. After shock application, the regions identified as abnormal by CMR showed significantly increased interstitial and myocardial cell areas in histological analysis. This increased cell area suggests significant cellular and interstitial edema.

Conclusion

Our pilot study data indicate that serial defibrillator shocks lead to acute skeletal muscle and myocardial injury. CMR is a useful tool to detect and localize myocardial and skeletal muscle injury early after transthoracic shocks in vivo. In the future the technique could potentially be used as an additional tool for quality control such as verifying insufficient local shock application in non-responders after cardioversion or to develop safer shock forms.

LysoPCs induce Hck- and PKCδ-mediated activation of PKCγ causing p47phox phosphorylation and membrane translocation in neutrophils

Lysophosphatidylcholines (lysoPCs) are effective polymorphonuclear neutrophil (PMN) priming agents implicated in transfusion-related acute lung injury (TRALI). LysoPCs cause ligation of the G2A receptor, cytosolic Ca²⁺ flux, and activation of Hck. We hypothesize that lysoPCs induce Hck-dependent activation of protein kinase C (PKC), resulting in phosphorylation and membrane translocation of 47 kDa phagocyte oxidase protein (p47^phox). PMNs, human or murine, were primed with lysoPCs and were smeared onto slides and examined by digital microscopy or separated into subcellular fractions or whole-cell lysates. Proteins were immunoprecipitated or separated by polyacrylamide gel electrophoresis and immunoblotted for proteins of interest. Wild-type (WT) and PKCγ knockout (KO) mice were used in a 2-event model of TRALI. LysoPCs induced Hck coprecipitation with PKCδ and PKCγ and the PKCδ:PKCγ complex also had a fluorescence resonance energy transfer (FRET)⁺ interaction with lipid rafts and Wiskott-Aldrich syndrome protein family verprolin-homologous protein 2 (WAVE2). PKCγ then coprecipitated with p47^phox Immunoblotting, immunoprecipitation (IP), specific inhibitors, intracellular depletion of PKC isoforms, and PMNs from PKCγ KO mice demonstrated that Hck elicited activation/Tyr phosphorylation (Tyr311 and Tyr525) of PKCδ, which became Thr phosphorylated (Thr507). Activated PKCδ then caused activation of PKCγ, both by Tyr phosphorylation (Τyr514) and Ser phosphorylation, which induced phosphorylation and membrane translocation of p47^phox In PKCγ KO PMNs, lysoPCs induced Hck translocation but did not evidence a FRET⁺ interaction between PKCδ and PKCγ nor prime PMNs. In WT mice, lysoPCs served as the second event in a 2-event in vivo model of TRALI but did not induce TRALI in PKCγ KO mice. We conclude that lysoPCs prime PMNs through Hck-dependent activation of PKCδ, which stimulates PKCγ, resulting in translocation of phosphorylated p47^phox.

Ischemic biomarker heart-type fatty acid binding protein (hFABP) in acute heart failure - diagnostic and prognostic insights compared to NT-proBNP and troponin I

Background

To evaluate diagnostic and long-term prognostic values of hFABP compared to NT-proBNP and troponin I (TnI) in patients presenting to the emergency department (ED) suspected of acute heart failure (AHF).

Methods

401 patients with acute dyspnea or peripheral edema, 122 suffering from AHF, were prospectively enrolled and followed up to 5 years. hFABP combined with NT-proBNP versus NT-proBNP alone was tested for AHF diagnosis. Prognostic value of hFABP versus TnI was evaluated in models predicting all-cause mortality (ACM) and AHF related rehospitalization (AHF-RH) at 1 and 5 years, including 11 conventional risk factors plus NT-proBNP.

Results

Additional hFABP measurements improved diagnostic specificity and positive predictive value (PPV) of sole NT-proBNP testing at the cutoff <300 ng/l to “rule out” AHF. Highest hFABP levels (4th quartile) were associated with increased ACM (hazard ratios (HR): 2.1–2.5; p = 0.04) and AHF-RH risk at 5 years (HR 2.8–8.3, p = 0.001). ACM was better characterized in prognostic models including TnI, whereas AHF-RH was better characterized in prognostic models including hFABP. Cox analyses revealed a 2 % increase of ACM risk and 3–7 % increase of AHF-RH risk at 5 years by each unit increase of hFABP of 10 ng/ml.

Conclusions

Combining hFABP plus NT-proBNP (<300 ng/l) only improves diagnostic specificity and PPV to rule out AHF. hFABP may improve prognosis for long-term AHF-RH, whereas TnI may improve prognosis for ACM.

Trial registration

ClinicalTrials.gov identifier: NCT00143793.

Inosine and hypoxanthine as novel biomarkers for cardiac ischemia: from bench to point-of-care

Cardiac ischemia associated with acute coronary syndrome and myocardial infarction is a leading cause of mortality and morbidity in the world. A rapid detection of the ischemic events is critically important for achieving timely diagnosis, treatment and improving the patient's survival and functional recovery. This minireview provides an overview on the current biomarker research for detection of acute cardiac ischemia. We primarily focus on inosine and hypoxanthine, two by-products of ATP catabolism. Based on our published findings of elevated plasma concentrations of inosine/hypoxanthine in animal laboratory and clinical settings, since 2006 we have originally proposed that these two purine molecules can be used as rapid and sensitive biomarkers for acute cardiac ischemia at its very early onset (within 15 min), hours prior to the release of heart tissue necrosis biomarkers such as cardiac troponins. We further developed a chemiluminescence technology, one of the most affordable and sensitive analytical techniques, and we were able to reproducibly quantify and differentiate total hypoxanthine concentrations in the plasma samples from healthy individuals versus patients suffering from ischemic heart disease. Additional rigorous clinical studies are needed to validate the plasma inosine/hypoxanthine concentrations, in conjunction with other current cardiac biomarkers, for a better revelation of their diagnostic potentials for early detection of acute cardiac ischemia.

Utility of Heart-type Fatty Acid Binding Protein as a New Biochemical Marker for the Early Diagnosis of Acute Coronary Syndrome

INTRODUCTION

Acute coronary syndrome (ACS) refers to a constellation of clinical symptoms caused by acute myocardial ischemia. Cardiovascular diseases (CVDs) are major and growing contributors to mortality and disability in India.

AIMS AND OBJECTIVES

Especially patients with non-ACS-related troponin elevations have an adverse outcome and require careful patient management. So, we look forward for another marker Heart-type Fatty Acid Binding Protein (H-FABP) that reliably detects myocardial ischemia in the absence of necrosis and would be useful for initial identification and for differentiating patients with chest pain of aetiology other than coronary ischemia.

MATERIALS AND METHODS

The study was done on 88 subjects of whom 34 subjects were with ischemic chest pain, 29 were with non-ischemic chest pain and 25 were normal subjects.

RESULTS

Receiver operating characteristic (ROC) curve analysis was done which showed that area under the curve (AUC) for H-FABP was 0.885(0.79-0.94) and that of high-sensitive Troponin T (hs-TnT) in initial six hours was 0.805(0.70-0.88). The specificity of H-FABP was higher compare to hs-TnT while sensitivity was comparable during 0-6 h of presentation of chest pain.

CONCLUSION

H-FABP can be used as an additional marker to hs-TnT in diagnosis of myocardial infarction (MI) and for exclusion of non-AMI (acute myocardial infarction) patients.

Serum biomarkers for the detection of cardiac toxicity after chemotherapy and radiation therapy in breast cancer patients

Multi-modality cancer treatments that include chemotherapy, radiation therapy, and targeted agents are highly effective therapies. Their use, especially in combination, is limited by the risk of significant cardiac toxicity. The current paradigm for minimizing cardiac morbidity, based on serial cardiac function monitoring, is suboptimal. An alternative approach based on biomarker testing, has emerged as a promising adjunct and a potential substitute to routine echocardiography. Biomarkers, most prominently cardiac troponins and natriuretic peptides, have been evaluated for their ability to describe the risk of potential cardiac dysfunction in clinically asymptomatic patients. Early rises in cardiac troponin concentrations have consistently predicted the risk and severity of significant cardiac events in patients treated with anthracycline-based chemotherapy. Biomarkers represent a novel, efficient, and robust clinical decision tool for the management of cancer therapy-induced cardiotoxicity. This article aims to review the clinical evidence that supports the use of established biomarkers such as cardiac troponins and natriuretic peptides, as well as emerging data on proposed biomarkers.

Preoperative serum h-FABP concentration is associated with postoperative incidence of acute kidney injury in patients undergoing cardiac surgery

Background

Fatty acid binding protein (FABP) is an intracellular transport protein associated with myocardial damage size in patients undergoing cardiac surgery. Furthermore, elevated FABP serum concentrations are related to a number of common comorbidities, such as heart failure, chronic kidney disease, diabetes mellitus, and metabolic syndrome, which represent important risk factors for postoperative acute kidney injury (AKI). Data are lacking on the association between preoperative FABP serum level and postoperative incidence of AKI.

Methods

This prospective cohort study investigated the association between preoperative h-FABP serum concentrations and postoperative incidence of AKI, hospitalization time and length of ICU treatment. Blood samples were collected according to a predefined schedule. The AKI Network definition of AKI was used as primary endpoint. All associations were analysed using descriptive and univariate analyses.

Results

Between 05/2009 and 09/2009, 70 patients undergoing cardiac surgery were investigated. AKI was observed in 45 patients (64%). Preoperative median (IQR) h-FABP differed between the AKI group (2.9 [1.7–4.1] ng/ml) and patients without AKI (1.7 [1.1–3.3] ng/ml; p = 0.04), respectively. Patients with AKI were significantly older. No statistically significant differences were found for gender, type of surgery, operation duration, CPB-, or X-Clamp time, preoperative cardiac enzymes, HbA1c, or CRP between the two groups. Preoperative h-FABP was also correlated with the length of ICU stay (r_s = 0.32, p = 0.007).

Conclusions

We found a correlation between preoperative serum h-FABP and the postoperative incidence of AKI. Our results suggest a potential role for h-FABP as a biomarker for AKI in cardiac surgery.

The cardioprotective effect of an aqueous extract of fermented rooibos (Aspalathus linearis) on cultured cardiomyocytes derived from diabetic rats

Diabetic cardiomyopathy (DCM) is a disorder of the heart muscle that contributes to cardiovascular deaths in the diabetic population. Excessive generation of free radicals has been directly implicated in the pathogenesis of DCM. The use of antioxidants, through dietary supplementation, to combat increased cellular oxidative stress has gained popularity worldwide. Aspalathus linearis (rooibos) is a popular herbal tea that contains a novel antioxidant, aspalathin. Literature has reported on the antidiabetic, anti-inflammatory and free radical scavenging effects of rooibos. However, its protective effect against DCM has not been established. Therefore, this study investigated whether chronic exposure to an aqueous extract of fermented rooibos (FRE) has an ex vivo cardioprotective effect on hearts obtained from streptozotocin (STZ) induced diabetic rats. Adult Wistar rats were injected with 40 mg/kg of STZ. Two weeks after STZ injection, cardiomyocytes were isolated and cultured. Cultured cardiomyocytes were treated with FRE (1 and 10 μg/ml), vitamin E (50 μg/ml), and n-acetyl cysteine (1mM) for 6h, before exposure to either hydrogen peroxide (H2O2) or an ischemic solution. Cardiomyocytes exposed to H2O2 or an ischemic solution showed a decrease in metabolic activity and glutathione content with a concomitant increase in apoptosis and intracellular reactive oxygen species. Pretreatment with FRE was able to combat these effects and the observed amelioration was better than the known antioxidant vitamin E. This study provides evidence that an aqueous extract of fermented rooibos protects cardiomyocytes, derived from diabetic rats, against experimentally induced oxidative stress and ischemia.

Diagnosis of Non-ST-Elevation Acute Coronary Syndrome by the Measurement of Heart-Type Fatty Acid Binding Protein in Serum: A Prospective Case Control Study

A prospective case control study was undertaken to evaluate the diagnostic performance of serum heart-type fatty acid binding protein (HFABP) in comparison to cardiac TnT and TnI in 33 patients admitted with chest pain, diagnosed as NSTE-ACS (non ST elevation acute coronary syndrome) and 22 healthy controls. Area under the receiver operating curve (AUC) was highest for H-FABP (AUC 0.79; 95% CI 0.66-0.89) versus cTnI (AUC 0.73; 95% CI 0.59-0.84) and cTnT (AUC 0.71; 95% CI 0.57-0.83). The H-FABP level above 6.5 ng/mL showed 56.7% (CI 37.4-74.5) sensitivity, 0.5 (95% CI 0.3-0.7) negative likelihood ratio (-LR), 100% (CI 84.6-100.0) specificity, and 100% (CI 79.4-100.0) positive predictive value (PPV), 62.9% (CI 44.9-78.5) negative predictive value (NPV). cTnI level above 0.009 μg/L had 40% (CI 22.7-59.4) sensitivity, 0.6 (95% CI 0.4-0.8) -LR, 100% (CI 84.6-100.0) specificity, 100% (CI 73.5-100.0) PPV, and 55% (CI 38.5-70.7) NPV. cTnT showed 46.7% (CI 28.3-65.7) sensitivity, 0.5 (95% CI 0.4-0.7) -LR, 100% (CI 84.6-100.0) specificity, 100% (CI 76.8-100.0) PPV, and 57.9% (CI 40.8-73.7) NPV at level above 9 μg/L. +LR were 12.5 (95% CI 1.8-86.8), 1.7 (95% CI 1.0-3.0), and 1.2 (95% CI 0.8-1.9) for H-FABP, cTnI, and cTnT respectively. In conclusion measurement of H-FABP is a valuable tool in the early diagnosis of patients with chest pain (6-8 hrs) and seems to be a preferred biomarker in the differential diagnosis of NSTE-ACS. More studies are needed to determine whether serum H-FABP further improves diagnostic performance.

Plasma free Fatty Acid concentrations as a marker for acute myocardial infarction

BACKGROUND

Acute myocardial infarction carries a high mortality among cardiac patients.The discovery of the fact that certain enzymes like CPK, LDH liberated into circulation following necrosis of the myocardial cells came as boon for physicians and patients. There has been a constant search of different parameters for the diagnosis and management of CoronaryArtery Diseases (CAD).

AIM

The present study was undertaken to investigate a possible relation between the changes in plasma free fatty acid (FFA) concentration and acute myocardial infarction.

MATERIAL AND METHODS

Fifty cases (25 males and 25 females) of acute myocardial infarction were selected for the present study. All the patients were in the age group of 40-70 years. For the control group fifty (25 male and 25 female) subjects of same age group were selected from patient's relatives and friends. Plasma free fatty acid concentration was estimated by Titrametric method of Trout et al., (1960), a modified version of Dole (1956).

STATISTICAL ANALYSIS

The statistical analysis of the data of the present study was done by using SPSS, version 14.0.1 was used.

RESULTS

Our study showed a significant increase in plasma FFA in the first 24 hours of acute myocardial infarction with subsequent normalisation on the 7th day.The difference between the first and the seventh day was statistically significant.

CONCLUSION

The FFA were found raised in cases of acute myocardial infarction.On the basis of present study, it is worth to say that estimation of serum free fatty acid should be done routinely at the earliest opportunity in all cases of acute myocardial infarction.

High peripheral levels of h-FABP are associated with poor prognosis in end-stage heart failure patients with mechanical circulatory support

Aim: To associate the time-course of h-FABP and N-terminal pro B-type natriuretic peptide (NT-proBNP)after left ventricular assist device (LVAD) implantation to outcome in end-stage heart failure patients. Materials & methods: Patients (n = 14, NYHA class III/IV; left ventricular ejection fraction <25% were enrolled; ten survived up to 1 month after LVAD (survivors) and four died of multiorgan failure within 2 weeks (nonsurvivors). Blood samples were obtained at admission; at 4, 24 and 72 h; and at 1 and 4 weeks after LVAD. Results: h-FABP significantly increases after surgery, decreasing since 72 h in all patients. At 72 h all survivor patients present h-FABP lower than the median value. N-terminal pro B-type natriuretic peptide is not associated with patient outcome at any time. Conclusion: High h-FABP levels, indicating the presence of more severe myocardial damage, are associated with a poor prognosis in patients with LVAD, suggesting that an early cardiac injury marker could improve the prediction of clinical outcome.

A proteomic view of isoproterenol induced cardiac hypertrophy: prohibitin identified as a potential biomarker in rats

Background

The present study aimed at using a proteomics based approach to: a) analyze and contrast the proteome of the healthy and isoproterenol induced hypertrophied hearts and b) identify potential biomarkers for diagnosis of cardiac hypertrophy.

Methods

Male Sprague Dawley (SD) rats were administered isoproterenol (ISO, 5 mg/kg, sc, once daily) for 14 days to induce cardiac hypertrophy. There was a significant (p<0.05) increase (~ 55%) in the heart weight to tail length ratio after 14 days of treatment and cardiac hypertrophy was evidenced by significant increase of β-MHC and ANP, two indicative markers of cardiac hypertrophy, in the treated heart compared to that of control. Following confirmation of hypertrophy, 2DE of the tissue samples was done followed by MS/MS analysis of the protein spots to obtain a proteomic view for identification of novel biomarkers.

Results

Several important proteins were identified by proteomics analysis. They belong to the major functional categories such as cholesterol and protein metabolism, muscle contraction and development, transport, TCAcycle, ATP-biosynthesis, chaperone, signal transduction, DNA synthesis and ubiquitinisation. Careful examination of these protein spots by image analysis led to the successful identification of 7 differentially expressed proteins in the diseased sample. Further extension of this work for validation of differential expression of these proteins was also achieved by RTPCR and western blotting.

Conclusions

Our results demonstrate characteristic protein expression profile in control and hypertrophy condition in SD rats and also expand the existing knowledge on differentially expressed proteins in hypertrophy. The study signifies the importance of reduced expression of a novel protein such as Prohibitin (PHB) which may be associated with the cardiomyocytes growth and cardiac hypertrophy. However, further work is necessary to confirm the role of PHB in human heart and its potential role in diagnostic and therapeutic intervention in the clinic.

Perioperative heart-type fatty acid binding protein levels in atrial fibrillation after cardiac surgery

BACKGROUND

Postoperative atrial fibrillation (POAF) is common and associated with poor outcomes. Perioperative ischemia can alter arrhythmic substrate.

OBJECTIVE

To demonstrate an association between perioperative measurements of heart-type fatty acid binding protein (HT-FABP), a sensitive marker of ischemic myocardial injury.

METHODS

Blood samples from 63 inpatients undergoing coronary artery bypass surgery, valve surgery, or both were obtained before and up to 4 days after surgery. Continuous telemetry monitoring was used to detect POAF. Fifty-nine patients had at least 3 HT-FABP measurements. The relationship of enzyme-linked immunosorbent assay-measured HT-FABP with POAF was assessed by using joint logistic regression adjusted for age and surgery type.

RESULTS

Thirty-five patients (55%) developed POAF; these were, on average, older (69.3±10 years vs 60±11 years; P = .0019), with a higher prevalence of heart failure (43% vs 17%; P = .034), chronic obstructive lung disease (26% vs 4%; P = .017), preoperative calcium channel blocker use (29% vs 7%; P = .031), and more likely to undergo combined surgery (21% vs 11%, P = .049). The joint age- and coronary artery bypass surgery-adjusted model revealed that postoperative but not preoperative HT-FABP levels predicted POAF (coefficient 1.9±0.87; P = .03). Longer bypass time, prior infarction, and worse renal function were all associated with higher postoperative HT-FABP.

CONCLUSIONS

A greater rise of HT-FABP is associated with atrial fibrillation after cardiac surgery, suggesting that ischemic myocardial damage is a contributing underlying mechanism. Interventions that decrease perioperative ischemic injury may also decrease the occurrence of POAF.

Heart type fatty acid binding protein response and subsequent development of atherosclerosis in insulin resistant polycystic ovary syndrome patients

Background

Women with polycystic ovary syndrome (PCOS) have higher risk for cardiovascular disease (CVD). Heart type fatty acid binding protein (HFABP) has been found to be predictive for myocardial ischemia.Wet ested whether HFABP is the predictor for CVD in PCOS patients, who have an increased risk of cardiovascular disease.

Methods

This was a prospective, cross sectional controlled study conducted in a training and research hospital.The study population consisted of 46 reproductive-age PCOS women and 28 control subjects. We evaluated anthropometric and metabolic parameters, carotid intima media thickness and HFABP levels in both PCOS patients and control group.

Results

Mean fasting insulin, homeostasis model assessment insulin resistance index (HOMA-IR), triglyceride, total cholesterol, low density lipoprotein cholesterol, free testosterone, total testosterone, carotid intima media thickness (CIMT) levels were significantly higher in PCOS patients. Although HFABP levels were higher in PCOS patients, the difference did not reach statistically significant in early age groups. After adjustment for age and body mass index, HFABP level was positive correlated with hsCRP, free testosterone levels, CIMT and HOMA-IR.

Conclusions

Heart type free fatty acid binding protein appeared to have an important role in metabolic response and subsequent development of atherosclerosis in insulin resistant, hyperandrogenemic PCOS patients.

Heart-type fatty acid-binding protein as a prognostic factor in patients with severe sepsis and septic shock

OBJECTIVE

This study was performed to evaluate whether heart-type fatty acid-binding protein (H-FABP) could predict 28-day mortality in patients with severe sepsis and septic shock.

METHODS

We performed a prospective observational study and included consecutive patients with severe sepsis and septic shock. Patients' demographic data, Acute Physiology and Chronic Health Evaluation (APACHE) II score, and the blood test results including H-FABP concentrations were compared between the 28-day survivors and nonsurvivors. The association between the concentration of H-FABP and survival was analyzed with multivariate logistic regression and Cox proportional hazards regression analyses. The prognostic performance of H-FABP was compared with those of the APACHE II score and albumin using the area under the receiver operating characteristic curve.

RESULTS

Of the 99 patients, 38 (38%) died. The mortality rate increased with increasing H-FABP concentration. In multivariate logistic regression analyses, H-FABP greater than 40 ng/mL was an independent predictor of mortality compared with H-FABP less than 7 ng/mL (odds ratios, 9.23; 95% confidence interval, 1.29-65.86). By Cox proportional hazards analysis, H-FABP greater than 40 ng/mL was associated with a 5.57-fold increased risk for death during the 28-day follow-up period (hazard ratio, 5.57; 95% confidence interval, 1.20-25.80). The area under the receiver operating characteristic curve of H-FABP was 0.739 (95% confidence interval, 0.640-0.839), which was comparable with those of the APACHE II score and albumin.

CONCLUSION

The H-FABP was an independent prognostic factor and could be a useful biomarker for 28-day mortality in patients with severe sepsis and septic shock.

Heart type fatty acid binding protein in relation to pharmacologic scintigraphy in coronary artery disease

BACKGROUND

Heart-type fatty acid-binding protein (H-FABP) is a marker of myocardial necrosis, but whether it increases during myocardial ischemia is not known. This study investigated whether serum levels of H-FABP change during adenosine stress testing and nuclear imaging in patients with stable coronary artery disease.

METHODS

Thirty stable patients with established coronary artery disease on their medications were studied. Sampling was performed before the stress test, at the end of adenosine infusion, as well as 1, 2 and 3 h after the completion of the infusion.

RESULTS

No difference in H-FABP serum levels were found at the five pre-specified time points in the overall group (p=0.99); furthermore, there was no significant difference regardless of the test result--positive (p=1) or negative (p=0.98).

CONCLUSIONS

It is concluded that H-FABP does not change significantly during pharmacologic stress testing in patients with known coronary artery disease and there is no difference whether there is inducible ischemia or not.

Gender-specific differences in biomarkers responses to acute coronary syndromes and revascularization procedures

A growing body of gender-related research in coronary artery disease is beginning to gradually elucidate differences between women and men. In patients presenting with acute coronary syndromes (ACS), these sex differences include varying risk factor profiles, accuracy of diagnostic testing, clinical presentations, treatment practices and outcomes. There is also a differential expression of cardiac biomarkers by sex, which remains unexplained. This paper reviews all the available information on the effect of gender on cardiac biomarkers by search of MEDLINE using the terms gender differences, biomarkers, ACS and revascularization procedures. A better understanding of the sex disparities in biomarkers along with all other clinical information is essential to optimal management and patient care in the future.