Heart-type Fatty Acid Binding Protein Concentrations Research Articles

Relationship between N-terminal pro-brain natriuretic peptide concentration and heart-type fatty acid-binding protein in postmortem urine

The clinical use of N-terminal pro-brain natriuretic peptide (NT-proBNP) and blood concentrations of heart-type fatty acid-binding protein (HFABP) is well-established in diagnosing heart conditions. However, their applicability in forensics is controversial due to postmortem changes. NT-proBNP and HFABP are excreted in the urine due to their small molecular weights and may be found in postmortem urine samples; however, their correlation has not been evaluated. In this study, we compared the concentrations of urinary NT-proBNP and HFABP in 386 forensic autopsy cases. The urinary NT-proBNP levels were significantly higher in acute myocardial infarction (AMI), congestive heart failure (CHF), sepsis, and hyperthermia cases, with the highest levels in CHF cases. Similarly, HFABP concentration was significantly higher in CHF, sepsis, and hyperthermia cases, with the highest level observed in hyperthermia cases. However, the difference in urinary HFABP levels between the AMI and control cases was not significant. Our analysis revealed a correlation between postmortem urine NT-proBNP and HFABP levels, and the NT-proBNP/HFABP ratio was high in patients with CHF and sepsis cases and low in those with hyperthermia. The difference between the ratios was possibly due to the combined release of ventricular myocardial cells in response to ventricular wall stress and myocardial injury for NT-proBNP, as well as myocardial and skeletal muscle injuries for HFABP. This study, for the first time, demonstrates the utility of postmortem measurements of urinary NT-proBNP and HFABP levels, offering valuable insights for improving the accuracy of postmortem diagnosis in forensic medicine.

TBICheck: a rapid test to rule-out CT scans in mild Traumatic Brain Injury patients

Introduction The TBICheck TM Rapid test is an immunochromatographic rapid test capable of assisting in the triage of patients with mild Traumatic Brain Injury (mTBI) suspected of brain lesions. It quantitatively determines heart-type Fatty Acid Binding Protein (H-FABP) levels in whole blood, serum, or plasma. The aim of the present study was to evaluate its technical performance and test it in two different cohorts of mTBI patients as a potential diagnostic tool for detecting brain lesions in patients with mTBI. Material and methods Description of the assay: Linearity and low limit of quantification (LLOQ) of TBICheck TM lateral flow assay were determined using serial dilution of standardized samples. Results were read using the TBICheck TM Reader, a mobile photometric immunoassay analyzer based on reflectance measurements to capture the optical density. Obtained results were compared to classical ELISA assays, Meso Scale Diagnostics (MSD). Patient cohorts: Two different cohorts of adult mTBI patients were included: a retrospective one including 82 patients and a prospective one including 65 patients. Values of H-FABP area under the curve (AUC), specificity (SP), sensitivity (SE) and negative predictive value (NPV) were calculated. Results The H-FABP dose response fitted a linear regression within the range of 0.5-25 ng/mL. LLOQ in blood was 0.5 ng/mL. High Spearman correlation was found (ρ=0.933, p<0.001) when MSD ELISA and TBICheck TM concentrations were compared. In the retrospective cohort, when the clinical sensitivity was set at 100%, a specificity value of 32.9% was obtained. In the prospective cohort, the SP value raised to 66.1% with 100% SE, meaning that 6 out of 10 patients might be discharged on the basis of their serum H-FABP concentration at hospital admission. Conclusions The quantification of H-FABP by using the TBICheck TM Rapid test on adult mTBI patients may allow to rule out the need of a CT-scan reducing the radiation exposure and avoiding the long waiting times in emergency units. It may lead to savings in hospital resources and assists medical doctors to provide the most appropriate treatment to the patients.

Ascorbic acid-mediated organic photoelectrochemical transistor sensing strategy for highly sensitive detection of heart-type fatty acid binding protein

Heart-type fatty acid binding protein (H-FABP) has been regarded as a promising biomarker for early diagnosis of acute myocardial infarction (AMI). Developing fast and reliable method for H-FABP detection is still highly desirable but challenging. Herein, an ascorbic acid (AA)-mediated organic photoelectrochemical transistor (OPECT) sensing strategy was reported for the detection of H-FABP in phosphate buffer saline (PBS) solution and human serum. A primary antibody/H-FABP/secondary antibody-Au NPs-alkaline phosphatase (ALP) sandwich immunorecognition structure was constructed. The modified ALP could catalytically convert ascorbic acid-2-phosphate to AA, which was then analyzed by OPECT. As a result, the AA-mediated OPECT sensing strategy realized highly sensitive detection of H-FABP with a detection limit of 3.23 × 10−14 g/mL which is two orders of magnitude lower than that of PEC method. Under optimal experimental conditions, H-FABP concentration could be obtained in ∼90 min. Importantly, the analysis of H-FABP was resistant to the interference from immunoglobulin G, bovine serum albumin, cysteine, AA and human serum. The proposed AA-mediated OPECT sensing strategy provides a simple, fast, and accurate way for H-FABP detection in AMI suspected patients.

Determination of 97.5th and 99th percentile upper reference limits for heart-type fatty acid-binding protein (H-FABP) in a US population

BackgroundHeart-type fatty acid binding protein (H-FABP), a low molecular weight protein found primarily in myocardial tissue, has been identified as a potential biomarker in the detection of acute coronary syndrome and acute kidney injury. To further investigate clinical utility, we sought to establish an upper reference limit (URL) of H-FABP within a healthy U.S. population. MethodsSerum samples of healthy donors were acquired from the AACC Universal Sample Bank. We analyzed 355 samples for H-FABP concentration using the Randox Laboratories immunoturbidimetric assay on the Roche Cobas 8000 series analyzer. ResultsThe final sample population consisted of individuals aged 18–74 y, with 170 males and 185 females. The distribution of the population exhibited a strong positive skew, affecting outlier analysis and URL determination. The 97.5th-percentile URL was found to be 7.4 ng/ml (95% CI: 6.3–9.2), while the 99th-percentile URL was 12.1 ng/ml (8.6–14.9). ConclusionAs the URL for H-FABP is highly affected by population distribution and outlier removal, final determination for an assay cutoff should be made in the context of clinical utility, either as a standalone assay or in conjunction with other biomarkers, and the desired clinical sensitivity and specificity.

Heart-type fatty acid binding protein is related to severity and established cardiac biomarkers of heart failure.

To determine concentrations of heart-type fatty acid-binding protein (HFABP) in patients with heart failure with reduced ejection fraction (HFrEF) and its potential value for prognostic assessment. Circulating levels of HFABP were measured with an automated chemiluminescent immunoassay in 25 healthy volunteers and 60 HFrEF patients. Concentrations of HFABP were significantly increased in heart failure patients in comparison to healthy volunteers. HFABP levels were significantly correlated to New York Heart Association classes and to established biomarkers of cardiac dysfunction and remodeling (amino-terminal pro-B-type natriuretic peptide [NT-proBNP], fibroblast growth factor 23, and galectin-3). HFABP concentrations were also predictive of cardiovascular (CV) death and combination with NT-proBNP might be synergistic for risk assessment. HFABP levels are increased in HFrEF patients, related to adverse CV outcomes, and might assist physicians for patient's management.

Early myocardial damage (EMD) and valvular insufficiency result in impaired cardiac function after multiple trauma in pigs

One third of multiple trauma patients present abnormal echocardiographic (ECHO) findings. Therefore, ECHO diagnostic after trauma is indicated in case of hemodynamic instability, shock, after chest trauma and after cardiac arrest. 20 male pigs underwent multiple trauma. Blood samples were collected 4 and 6 h after trauma and concentrations of heart-type fatty acid binding protein (HFABP) as a biomarker for EMD were measured. Myocardial damage was evaluated by scoring Hematoxylin–Eosin stained sections. At baseline, 3 and 6 h after trauma, transesophageal ECHO (TOE) was performed, invasive arterial and left ventricular blood pressure were measured to evaluate the cardiac function after multiple trauma. Systemic HFABP concentrations were elevated, furthermore heart injury score in multiple trauma animals was increased determining EMD. A significant decrease of blood pressure in combination with a consecutive rise of heart frequency was observed. Ongoing depression of mean arterial pressure and diastolic blood pressure were accompanied by changes in ECHO-parameters indicating diastolic and systolic dysfunction. Furthermore, a valvular dysfunction was detected. In this study complex myocardial and valvular impairment after multiple trauma in pigs has been observed. Therefore, detection of EMD and progressive valvular dysfunction might be crucial and therapeutically relevant.

Changes of Certain Metabolic and Cardiovascular Markers Fructosamine, H-FABP and Lipoprotein (a) in Patients with Hypothyroidism

Background:Disorders of thyroid gland are common in general population, and it’s the most common affecting the endocrine system after diabetes mellitus. Thyroid function regulates a wide range of metabolic parameters, as well as affects some cardiovascular disease risk factors. Fructosamine is produced by a reaction between albumin (protein) and glucose; it is used to monitor patients with diabetes for short-term glycemic changes. H-FABP is present in the cytoplasm of cardiac myocytes, and delivers fatty acids into these cells. It has been shown to increase in myocardial injury. Lipoprotein LP(a) is consist of a special apolipoprotein called apoprotein (a), and it’s recognized as a cardiovascular disease independent risk factor.Objective:To study whether certain metabolic and cardiovascular markers (fructosamine, H-FABP and lipoprotein (a) are changed in hypothyroid patients.Methods:The current study included 280 overt hypothyroid, 272 with subclinical hypothyroidism compared with 270 healthy individuals of matched age and gender. For all subjects serum (TSH, T4, T3, FBS, HbA1c, fructosamine, triglycerides, cholesterol, lipoprotein (a), and Heart-type Fatty Acid-Binding Protein (H-FABP)) was measured.Results:Serum fructosamine level significantly elevated (p value <0.05) in patient with hypothyroidism when compared with control group, and no significant change between subclinical and control groups. There is no significant change in serum H-FABP between study subjects. There is significant increase in lipoprotein (a) in patient with hypothyroidism and those with subclinical group when compared with control group.Conclusion:Serum fructosamine and level is significantly changed in patients with overt hypothyroidism when compared with euthyroid subjects. Also, we conclude that hypothyroidism increase risk of cardiovascular diseases by changing non-traditional marker such as lipoprotein (a), and no effect on H-FABP concentration.

The role of human heart-type Fatty Acid Binding Protein in the early detection of myocardial injury in Acute Coronary Syndrome

Objectives: To evaluate the use of H-FABP as a novel marker in early detection of cardiac damage (MI) in patients presenting with symptoms of acute coronary syndrome (ACS). Methods: This cross-sectional study included 250 subjects; 125 patients of ACS presenting within four hours of the onset of chest pain and/dyspnea and 125 age and sex-matched healthy controls. An initial blood sample was taken from patients at presentation. Blood samples of healthy control subjects were also taken. The blood samples of both groups were centrifuged and stored at -200 C for H-FABP analysis. All the patients and control subjects were thoroughly examined and detailed history was taken. The diagnostic test was troponin-T.H-FABP concentrations of all samples were measured by ELISA-kit. The results were analyzed statistically. A p-value≤0.05 was considered statistically significant. Results: In 125 patients of ACS, H-FABP showed a sensitivity of 85% and specificity of 83.3% for acute MI diagnosis at a cut-off level of 16 ng/ml. Positive predictive values and negative predictive values were 96.8% and 48.4% respectively. The accuracy was 84.4%and the area under the ROC curve was 0.842. Conclusion: Evaluation of heart-type fatty acid-binding Protein (H-FABP) within four hours of onset ACS symptoms may be a valuable tool in the diagnosis of AMI. Keywords: Heart-type fatty acid-binding protein, Acute coronary syndrome, Myocardial infarction.

Serum heart-type fatty acid-binding protein as a predictor for the development of sepsis-associated acute kidney injury

ABSTRACTBackground: We analyzed the correlation between heart-type fatty acid-binding protein (HFABP) and the development of acute kidney injury (AKI) in patients with sepsis and estimated the predictive capacity of HFABP for sepsis-associated acute kidney injury (SAKI).Methods: In this retrospective observational study, we screened 2,452 patients who received the HFABP test in the emergency department. 442 admitted patients with sepsis were finally enrolled. Based on the diagnostic criteria for AKI in Kidney Disease: Improving Global Outcomes (KDIGO) guidelines, patients were divided into the no-AKI group (n = 317) and AKI group (n = 125). We analyzed the correlation between HFABP and SAKI occurrence by logistic regression analysis and evaluated the predictive ability of HFABP to SAKI using c-index, net reclassification improvement index (NRI) and integrated discrimination improvement index (IDI).Results: Patients in the AKI group with significantly higher the level of HFABP and in-hospital mortality. HFABP concentration is an independent risk factor for SAKI (OR: 11.398; 95% CI: 6.218–20.891, P < 0.001), but not for in-hospital mortality (OR: 1.189, 95%CI: 0.954–2.607, P = 0.076). The addition of HFABP to the prediction model significantly improved the ROC area (0.867 vs 0.755, P < 0.001), NRI 25.03% (95% CI 9.72–38.51%) and IDI 14.33 (95% CI 11.04–17.62).Conclusion: Serum HFABP is correlated with SAKI development and could become a potential predictive biomarker.

Acute Responses of Novel Cardiac Biomarkers to a 24-h Ultra-Marathon.

The aim of the present study was to examine the acute effect of an ultra-endurance performance on N-terminal pro-brain natriuretic peptide (NT-proBNP), cardiac specific troponin T (cTnT), creatinine kinase-myocardial band (CK-MB), high sensitive C-reactive protein (hsCRP), ischemia modified albumin (IMA), heart-type fatty acid binding protein (H-FABP) and cardiovascular function. Cardiac biomarkers were evaluated in 14 male ultra-marathoners (age 40 ± 12 years) during a 24 h ultra-marathon at five points (i.e., Pre-race; Marathon, 12-h run, 24-h run, and 48-h post-race). All subjects underwent baseline echocardiography assessment at least 10 days prior to the ultra-marathon and 48 h post-race. The average distance covered during the race was 149.4 ± 33.0 km. Running the ultra-marathon led to a progressive increase in hsCRP and H-FABP concentrations (p < 0.001). CK-MB and cTnT levels were higher after a 24-h run compared to pre-race (p < 0.05). Diastolic function was altered post-race characterized by a reduction in peak early to late diastolic filling (p < 0.01). Running an ultra-marathon significantly stimulates specific cardiac biomarkers; however, the dynamic of secretion of biomarkers linked to myocardium ischemia were differentially regulated during the ultra-marathon race. It is suggested that both exercise duration and intensity play a crucial role in cardiovascular adaptive mechanisms and cause risk of cardiac stress in ultra-marathoners.

Influences of Ivabradine treatment on serum levels of cardiac biomarkers sST2, GDF-15, suPAR and H-FABP in patients with chronic heart failure

Chronic heart failure (CHF) represents a major cause of hospitalization and death. Recent evidence shows that novel biomarkers such as soluble suppression of tumorigenicity (sST2), growth-differentiation factor-15 (GDF-15), soluble urokinase plasminogen activator receptor (suPAR) and heart-type fatty acid binding protein (H-FABP) are correlated with inflammatory and ischemic responses in CHF patients. In this study we examined the effects of Ivabradine that inhibited the hyperpolarization-activated cyclic nucleotide-gated channel (HCN channel, also called funny current If), thereby leading to selective heart rate reduction and improved myocardial oxygen supply on the cardiac biomarkers sST2, GDF-15, suPAR and H-FABP in 50 CHF patients at the University Hospital of Jena. Patients were divided into three groups based on the etiology of CHF: dilated cardiomyopathy (DCM, n=20), ischemic cardiomyopathy (ICM, n=20) and hypertensive cardiomyopathy (HCM, n=10). The patients were administered Ivabradine (5 mg, bid for 3 months, and 7.5 mg bid for further 3 months). Analyses of cardiovascular biomarkers were performed at baseline as well as at 3- and 6-month follow-ups. At 6-month follow-up, GDF-15 levels were significantly reduced compared to baseline levels (P=0.0215), indicating a reduction in the progress of cardiac remodeling. H-FABP concentration was significantly lower in DCM patients compared to ICM (1.89 vs 3.24 μg/mL) and HCM patients (1.89 vs 3.80 μg/mL), and decreased over the 6-month follow-up (P=0.0151). suPAR median levels remained elevated, implying major ongoing inflammatory processes. As shown by significant decreases in GDF-15 and H-FABP levels, a reduction in ventricular remodeling and sub-clinical ischemia could be assumed. However, markers of hemodynamic stress (sST2) and inflammation (suPAR) showed no change or progression after 6 months of Ivabradine treatment in CHF patients. Further studies are necessary to validate the clinical applicability of these novel cardiovascular biomarkers.

A Microfluidic Fluorescence Immunoassay Test Card for Rapid Detection of Heart-type Fatty Acid Binding Protein

Abstract A kind of easily assembly self-driving test card was developed for the rapid detection and quantification of heart-type fatty acid binding protein (H-FABP) utilizing time-resolved fluorescence microspheres as signal probes. It was easy to make microfluidic channel structures with double-sided adhesive and cut out of test card substrate and cover based on polymethyl methacrylate (PMMA) material by the laser cutting technique. The membrane of polystyrene containing maleic anhydride functional groups was coated on PMMA plate surface by dip-coating method. Furthermore, the capture antibody was immobilized effectively on PMMA surface by covalent binding with maleic anhydride groups. The cover was treated with plasma treatment to improve the hydrophilic ability, so that the liquid could flow smoothly in the microchannel. The whole analysis process could be completed within 10 min. There was a very good linear correlation between response and H-FABP concentration in the range of 0.5−100 ng mL−1 (R2 = 0.9966), and the detection limit was 0.1 ng mL−1 (S/N = 3). The intra-assay precision was less than 10% and the inter-assay precision was less than 15%. This detection method has the advantages such as high sensitivity, fast detection and good accuracy.

Heart-Type Fatty Acid-Binding Protein, in Early Detection of Acute Myocardial Infarction: Comparison with CK-MB, Troponin I and Myoglobin.

The study aimed to investigate whether heart-type fatty acid binding protein (H-FABP) measurement provides additional diagnostic value to that of conventional cardiac markers in acute myocardial infarction (AMI) within first 6h after the onset of symptoms. The study included 120 subjects: 60 AMI cases and 60 age and sex matched controls. The cases and controls were further divided into 2 subgroups depending on the time since onset of chest pain as (1) subjects within 3h and (2) between 3 and 6h of onset of chest pain. In all the cases and controls, serum H-FABP concentration was measured by Immunoturbidimetric method, serum Troponin I and myoglobin concentrations by Chemiluminescence immunoassay and serum CK-MB concentration by Immuno-inhibition method. The sensitivity, specificity, positive and negative predictive values of H-FABP were significantly greater than CK-MB and myoglobin but were lesser than Troponin I in patients with suspected AMI in both within 3h and 3-6h groups. Receiver operating characteristic curves demonstrated greatest diagnostic ability for Troponin I (AUC=0.99, p<0.001) followed by H-FABP (AUC=0.906, p<0.001) within 3h and 3-6h after the onset of chest pain. In conclusion, the diagnostic value of H-FABP is greater than CK-MB and myoglobin but slightly lesser than troponin I for the early diagnosis of AMI within first 6h of chest pain. H-FABP can be used as an additional diagnostic tool for the early diagnosis of AMI along with troponin I.

RESEARCH ON CONCENTRATION CHANGE OF H-FABP IN EARLY DIAGNOSIS OF ACUTE MYOCARDIAL INFARCTION

Objective: To evaluate the change of H-FABP in patients with Acute Myocardial Infarction at the time of 6 hours previously and 24 hours afterwards. To identify the sensitivity, specificity, positive predictive and negative predictive values, H-FABP cutoff point in comparison with hs troponin T. Methods: prospective study on 84 patients with Acute Myocardial Infarction and 28 healthy volunteers at Da Nang Hospital. The study period lasts from March 2014 to June 2015. Results: The average age of the diseased group is 62.57 ± 12.91 and the control group is 55.43 ± 12.33; a higher percentage of men than women 3 times in the disease group, 2 times compared with women in the control group. Regarding change of H-FABP concentrations in Acute Myocardial Infarction: H-FABP increased within 30 minutes after the onset, increased rapidly in the duration from 0-6 hours, peaked after 6-12 hours with the average concentration of 245.13 ± 452.63 ng/ml and returned to normal state after 36 hours. Meanwhile, hs troponin T appeared slower in blood after 3-6 hours, peaked after 12-24 hours at a concentration of 4.52 ± 3.38 average ng/ml. H-FABP and hs troponin T concentrations had significant difference statistically between the intervals with p &lt;0,05. According to the results of our study: cutoff point of H-FABP was 6.6 ng/ml, sensitivity 88.1%, specificity 82.1%; compared with hs troponin T, the cutoff point was 0.014 ng/ml, sensitivity 82.1%, specificity 96.4%. If combining H-FABP with hs troponin T, the sensitivity will increase to 92.6% and specificity of 82.1%. The sensitivity, specificity, positive predictive and negative predictive values of H-FABP and hs of troponin T in the duration of 0-3 hours, were 89.3%, 82.1%, 93.7%, 69.7% and 53.3 %, 89.3%, 84.3%, 64.1% respectively; in the duration of 3-6 hours were 91.7%, 83.3%, 83.3%, 88.5% and 83.3%, 91.7%, 90.6%, 84.6% respectively; so in the duration of 0-6 hours, the H-FABP sensitivity was higher than that of hs troponin T; If combining H-FABP and hs troponin T, the sensitivity would increase at all time, Specifically, within 0-3 hours, 3-6 hours, 3-12 hours, 12-24 hours, and &gt; 36 hours the sensitive was 92.9%, 95.8%, 94.7%, 96.2%, 90.6%, 85.7% respectively. The area under the ROC curve point of H-FABP 0-3 hours is 0.921 and the hs troponin T was 0.918. Conclusion: The study asserted that H-FABP is a superior biomarker in terms of sensitivity, more superior to hs troponin T in diagnosing myocardial necrosis in the early phase of 0-6 hours, the golden hours of acute MI; which helps make important decisions on treatment methods, risk stratification and prognosis. Keywords: marker, H-FABP (Heart type Fatty Acid Binding Protein), hs troponin T (high sensitive troponin T), acute myocardial infarction.

Rapidly rule out acute myocardial infarction by combining copeptin and heart-type fatty acid-binding protein with cardiac troponin.

The rapid exclusion of acute myocardial infarction in patients with chest pain can reduce the length of hospital admission, prevent unnecessary diagnostic work-up and reduce the burden on our health-care systems. The combined use of biomarkers that are associated with different pathophysiological aspects of acute myocardial infarction could improve the early diagnostic assessment of patients presenting with chest pain. We measured cardiac troponin I, copeptin and heart-type fatty acid-binding protein concentrations in 584 patients who presented to the emergency department with acute chest pain. The diagnostic performances for the diagnosis of acute myocardial infarction and NSTEMI were calculated for the individual markers and their combinations. Separate calculations were made for patients presenting to the emergency department <3 h, 3-6 h and 6-12 h after chest pain onset. For ruling out acute myocardial infarction, the net predictive values (95% CI) of cardiac troponin I, copeptin and heart-type fatty acid-binding protein were 90.4% (87.3-92.9), 84% (79.8-87.6) and 87% (83.5-90), respectively. Combining the three biomarkers resulted in a net predictive value of 95.8% (92.8-97.8). The improvement was most pronounced in the early presenters (<3 h) where the combined net predictive value was 92.9% (87.3-96.5) compared to 84.6% (79.4-88.9) for cardiac troponin I alone. The area under the receiver operating characteristic for the triple biomarker combination increased significantly (P < 0.05) compared to that of cardiac troponin I alone (0.880 [0.833-0.928] vs. 0.840 [0.781-0.898], respectively). Combining copeptin, heart-type fatty acid-binding protein and cardiac troponin I measurements improves the diagnostic performance in patients presenting with chest pain. Importantly, in patients who present early (<3 h) after chest pain onset, the combination improves the diagnostic performance compared to the standard cardiac troponin I measurement alone.

Effects of different fatty acid chain lengths on fatty acid oxidation-related protein expression levels in rat skeletal muscles.

Skeletal muscles can adapt to dietary interventions that affect energy metabolism. Dietary intake of medium-chain fatty acids (MCFAs) enhances mitochondrial oxidation of fatty acids (FAO) in type IIa skeletal muscle fibers. However, the effect of MCFAs diet on mitochondrial or cytoplasmic FAO-related protein expression levels in different types of muscle fibers remains unclear. This study aims to examine the effects of a high-fat diet, containing MCFAs, on mitochondrial enzyme activities and heart-type fatty acid-binding protein (H-FABP) levels in different types of skeletal muscle fibers. Five-week-old male Wistar rats were assigned to one of the following three dietary conditions: standard chow (SC, 12% of calories from fat), high-fat MCFA, or high-fat long-chain fatty acids (LCFAs) diet (60% of calories from fat for both). The animals were provided food and water ad libitum for 4 weeks, following which citrate synthase (CS) activity and H-FABP concentration were analyzed. The epididymal fat pads (EFP) were significantly smaller in the MCFA group than in the LCFA group (p < 0.05). MCFA-fed group displayed an increase in CS activity compared with that observed in SC-fed controls in all types of skeletal muscle fibers (triceps, surface portion of gastrocnemius (gasS), deep portion of gastrocnemius (gasD), and soleus; p < 0.05,). H-FABP concentration was significantly higher in the LCFA group than in both the SC-fed and MCFA-fed groups (triceps, gasS, gasD, and soleus; p < 0.05,). However, no significant difference was observed in the H-FABP concentrations between the SC-fed and MCFA-fed groups. The results of this study showed that the MCFA diet can increase the expression of the mitochondrial enzyme CS, but not that of H-FABP, in both fast- and slow-twitch muscle fibers, suggesting that H-FABP expression is dependent on the chain length of fatty acids in the cytoplasm of skeletal muscles cells.

Heart-Type Fatty Acid Binding Protein: A Better Cardiac Biomarker than CK-MB and Myoglobin in the Early Diagnosis of Acute Myocardial Infarction.

Early diagnosis and therapeutic intervention can improve the outcome of acute myocardial infarction (AMI). However, there are no satisfactory cardiac biomarkers for the diagnosis of AMI within 6 hours of onset of symptoms. Among novel biochemical markers of AMI, heart-type fatty acid binding protein (H-FABP) is of particular interest. To compare the diagnostic value of H-FABP with that of CK-MB and myoglobin in suspected AMI patients within first 6 hours after the onset of symptoms. The study includes 40 AMI cases and 40 non-cardiac chest pain otherwise healthy controls. The cases and controls were further divided into 2 groups depending on the time since chest pain as those subjects within 3 hours and those between 3-6 hours of onset of chest pain. In all the cases and controls, serum H-FABP, CK-MB and myoglobin concentrations were measured by Immunoturbidimetric method, immuno-inhibition method and Chemiluminescence immunoassay respectively. Data is presented as mean ± SD values. Differences between means of two groups were assessed by Student t-test. Sensitivity, Specificity, Positive predictive value, Negative predictive values were calculated and ROC curve analysis was done to assess the diagnostic validity of each study parameter. The sensitivity, specificity, PPV, NPV of H-FABP were greater than CK-MB and myoglobin and ROC curve analysis demonstrated highest area under curve for H-FABP followed by myoglobin and CK-MB in patients with suspected AMI both within 3 hours and 3-6 hours after the onset of chest pain. The diagnostic efficiency of H-FABP is greater than CK-MB and myoglobin for the early diagnosis of AMI within first 6 hours of chest pain. H-FABP can be used as an additional diagnostic tool for the early diagnosis of AMI.

Increased H-FABP concentrations in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disorder which is reported as the hepatic manifestation of metabolic syndrome with an increased risk of cardiovascular events. Patients with NAFLD are also at risk of future cardiac events independently of metabolic syndrome. The aim of this study was to examine serum concentrations of heart type fatty acid binding protein (H-FABP) in NAFLD and to investigate its correlations with metabolic parameters and subclinical atherosclerosis. A total of 34patients with NAFLD and 35 healthy subjects were enrolled in the study. NAFLD patients had elevated liver enzymes and steatosis graded on ultrasonography. Healthy subjects had normal liver enzymes and no steatosis on ultrasonography. H-FABP levels were measured using an enzyme linked immunosorbent assay (ELISA) method and correlations with metabolic parameters and subclinical atherosclerosis were examined. Subclinical atherosclerosis was determined with carotid artery intima-media thickness (CIMT) which was measured by high resolution B mode ultrasonography. H-FABP levels were elevated in patients with NAFLD (16.3 ± 4.0ng/ml) when compared with healthy controls (13.8 ± 2.1ng/ml; p < 0.001). NAFLD patients had significantly higher CIMT than the controls had (0.64 ± 0.17mm vs. 0.43 ± 0.14mm, p = 0.009). The H-FABP concentrations were significantly positively correlated with body mass index (r = 0.255, p = 0.042), fasting blood glucose level (r = 0.300, p = 0.013), CIMT (r = 0.335, p = 0.043), and homeostasis model assessment-estimated insulin resistance (HOMA-IR; r = 0.156, p = 0.306). In multiple linear regression analysis, H-FABP levels were only independently associated with CIMT (p = 0.04) Serum H-FABP concentrations increase in patients with NAFLD. Our results may not only suggest that H-FABP is a marker of subclinical myocardial damage in patients with NAFLD but also of subclinical atherosclerosis, independent of metabolic syndrome and cardiac risk factors.

Plasma reference value of heart-type fatty acid-binding protein, the earliest available plasma biomarker of acute myocardial infarction

More rapid triaging of patients suspected for acute myocardial infarction (AMI) is needed to facilitate early initiation of appropriate therapy in patients with AMI and to exclude low-risk patients who can safely be sent home. Heart-type fatty acid-binding protein (H-FABP) is established to be the earliest available plasma marker for AMI diagnosis. There is a paucity of data on circulating levels of H-FABP in the general population. In this study we applied a H-FABP immunoassay with improved analytical performance to assess plasma H-FABP reference values in a relatively large group (n = 443) of healthy subjects aged 18-69 y. Mean (±SD) plasma H-FABP concentration was 1.7 ± 0.9 ng/mL, with somewhat higher values found in males than in females. Plasma H-FABP also increases with age, as previously reported. The 99th centile was obtained for subjects aged 41-69 years and amounted to 5.6 ng/mL.

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

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. 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. 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. 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.