Mitochondrial DNA copy number associates with insulin sensitivity and aerobic capacity, and differs between sedentary, overweight middle-aged males with and without type 2 diabetes.

Background/objectives: Increased risk of type 2 diabetes mellitus (T2DM) is linked to impaired muscle mitochondrial function and reduced mitochondrial DNA copy number (mtDNA). However, studies have failed to control for habitual physical activity levels, which directly influences both mtDNA copy number and insulin sensitivity. We, therefore, examined whether physical conditioning status (maximal oxygen uptake, V̇O) was associated with skeletal muscle mitochondrial volume and mtDNA, and was predictive of T2DM in overweight, middle-aged men.

Fatty acid- and cholesterol transporter protein expression along the human intestinal tract.

Background: Protein distribution profiles along the human intestinal tract of transporters involved in the absorption of cholesterol and long-chain fatty acids (LCFA) have been scarcely evaluated.

Methodology/principal Findings: In post-mortem samples from 11 subjects, intestinal transporter distribution profiles were determined via Western Blot. Differences in transporter protein levels were statistically tested using ANOVA and Tukey's Post Hoc comparisons.

Cardiac dysfunction and cell damage across clinical stages of severity in growth-restricted fetuses.

Objective: The purpose of this study was to assess cardiac function and cell damage in intrauterine growth-restricted (IUGR) fetuses across clinical Doppler stages of deterioration.

Study Design: One hundred twenty appropriate-for-gestational-age and 81 IUGR fetuses were classified in stages 1/2/3 according umbilical artery present/absent/reversed end-diastolic blood flow, respectively. Cardiac function was assessed by modified-myocardial performance index, early-to-late diastolic filling ratios, cardiac output, and cord blood B-type natriuretic peptide; myocardial cell damage was assessed by heart fatty acid-binding protein, troponin-I, and high-sensitivity C-reactive protein.

Fatty acid-binding protein as marker for renal injury.

The assessment of biomarkers to detect renal injury has been studied before, but the sensitivity and specificity of urinary and serum profiles of these markers still need to be improved. One of the promising new markers for detection of renal injury is the family of 15 kDa cytoplasmic fatty acid-binding proteins (FABPs). Remarkably, however, the application of FABP as marker for renal injury due to ischaemia, toxic heavy metals or in end-stage renal failure has only recently been investigated.

The role of membrane fatty-acid transporters in regulating skeletal muscle substrate use during exercise.

While endogenous carbohydrates form the main substrate source during high-intensity exercise, long-chain fatty acids (LCFA) represent the main substrate source during more prolonged low- to moderate-intensity exercise. Adipose tissue lipolysis is responsible for the supply of LCFA to the contracting muscle. Once taken up by skeletal muscle tissue, LCFA can either serve as a substrate for oxidative phosphorylation or can be directed towards esterification into triacylglycerol.

Identification of protein kinase D as a novel contraction-activated kinase linked to GLUT4-mediated glucose uptake, independent of AMPK.

Contraction-induced glucose uptake is only partly mediated by AMPK activation. We examined whether the diacylglycerol-sensitive protein kinase D (PKD; also known as novel PKC isoform mu) is also involved in the regulation of glucose uptake in the contracting heart. As an experimental model, we used suspensions of cardiac myocytes, which were electrically stimulated to contract or treated with the contraction-mimicking agent oligomycin.

FABP3 and FABP10 in Atlantic salmon (Salmo salar L.)--general effects of dietary fatty acid composition and life cycle variations.

The increased use of dietary plant oil supplementation combined with high dietary lipid loads challenges the lipid transport systems of cultivated fish species. Fatty acid binding proteins (FABPs) have been thoroughly studied as intracellular fatty acid transporters in vertebrates, but no data have been reported in Atlantic salmon. In the present study, comparative characterizations were performed, and dietary influence of plant oil supplementation on FABP3 and FABP10 expression was studied for several tissues in two separate dietary trials.

Plasma heart-type fatty acid binding protein is superior to troponin and myoglobin for rapid risk stratification in acute pulmonary embolism.

Background: Irreversible right ventricular (RV) failure with myocardial damage may precipitate fatal outcome in acute pulmonary embolism (APE). Cytoplasmic heart-type fatty acid binding protein (H-FABP) is a sensitive and specific biomarker of myocardial damage. We assessed which biomarker of myocardial damage or RV stretching is the most useful for short-term risk stratification in APE.

Purification, immunochemical quantification and localization in rat heart of putative fatty acid translocase (FAT/CD36).

Evidence is accumulating that the heavily glycosylated integral membrane protein fatty acid translocase (FAT/CD36) is involved in the transport of long-chain fatty acids across the sarcolemma of heart muscle cells. The aim of this study was to analyse the distribution between FAT/CD36 present in cardiac myocytes and endothelial cells. We therefore developed a method to purify FAT/CD36 from total rat heart and isolated cardiomyocytes, and used the proteins as standards in an immunochemical assay.

Unbound free fatty acids and heart-type fatty acid-binding protein: diagnostic assays and clinical applications.

Background: A biomarker that reliably detects myocardial ischemia in the absence of necrosis would be useful for initial identification of unstable angina patients and for differentiating patients with chest pain of an etiology other than coronary ischemia, and could provide clinical utility complementary to that of cardiac troponins, the established markers of necrosis. Unbound free fatty acids (FFA(u)) and their intracellular binding protein, heart-type fatty acid-binding protein (H-FABP), have been suggested to have clinical utility as indicators of cardiac ischemia and necrosis, respectively.

Methods: We examined results of clinical assessments of FFA(u) and H-FABP as biomarkers of cardiac ischemia and necrosis.

Detection of brain injury by fatty acid-binding proteins.

The rapid detection of brain injury (neuronal damage in general) is an important parameter in the management of cerebrovascular accidents, especially in hemorrhagic and/or ischemic events. Two types of 15-kDa cytoplasmic fatty acid-binding proteins (FABPs), brain-type FABP and heart-type FABP, have recently been postulated as novel markers for brain injury detection. Here we review the possible roles of these FABPs as rapid diagnostic markers for the detection of brain injury due to cerebrovascular accident, trauma or neurodegenerative diseases.

Rapid analysis of fatty acid-binding proteins with immunosensors and immunotests for early monitoring of tissue injury.

Fatty acid-binding protein (FABP) holds promise for early detection of tissue injury. This small protein (15kD) appears earlier in the blood than large proteins after cell damage. Combined its characteristics of high concentration tissue contents and low normal plasma values provide the possibility of a rapid rise above the respective reference values, and thus an early indication of the appearance of tissue injury.

Release of brain-type and heart-type fatty acid-binding proteins in serum after acute ischaemic stroke.

This study aimed at an analysis of the release of Braintype and Heart-type Fatty Acid- Binding Proteins (B-FABP and HFABP) in acute ischaemic stroke and their potential value as neurobiochemical markers of brain damage. We investigated 42 consecutive patients admitted within 6 hours after ischaemic stroke. Serial venous blood samples were taken hourly between 1 to 6 hours, and at 12, 18, 24, 48, 72, 96, and 120 hours after stroke onset.

Brain- and heart-type fatty acid-binding proteins in the brain: tissue distribution and clinical utility.

Background: Detection of brain injury by serum markers is not a standard procedure in clinical practice, although several proteins, such as S100B, neuron-specific enolase (NSE), myelin basic protein, and glial fibrillary acidic protein, show promising results. We investigated the tissue distribution of brain- and heart-type fatty acid-binding proteins (B-FABP and H-FABP) in segments of the human brain and the potential of either protein to serve as plasma marker for diagnosis of brain injury.

Methods: B-FABP and H-FABP were measured immunochemically in autopsy samples of the brain (n = 6) and in serum samples from (a) patients with mild traumatic brain injury (MTBI; n = 130) and (b) depressed patients undergoing bilateral electroconvulsive therapy (ECT; n = 14).

Intestinal-type and liver-type fatty acid-binding protein in the intestine. Tissue distribution and clinical utility.

Objectives: Intestinal-type fatty acid-binding protein (I-FABP) has been proposed as plasma marker for the detection of acute intestinal injury. However, intestinal mucosa also expresses liver-type FABP (L-FABP). We have investigated the tissue distribution of I-FABP and L-FABP in segments of the human intestine along the duodenal to colonal axis and the potential of both proteins to serve as plasma marker for the diagnosis of intestinal injury.

Comparison of perfusate activities of glutathione S-transferase, alanine aminopeptidase and fatty acid binding protein in the assessment of non-heart-beating donor kidneys.

Background: With a universal shortage of donor organs, screening and selection of marginal kidneys from non-heart-beating donors (NHBDs) provides a valuable source for transplantation. Pre-transplant viability assessment is based on a combination of flow characteristics and assessment of ischaemic tissue injury during NHBD kidney machine perfusion by measurement of total glutathione S-transferase (GST) activity. Successful viability screening has facilitated 69 renal transplants from 60 NHBDs within our transplant centre since 1998, with a first-year graft survival of 90.