Histochemical localization of heart-type fatty-acid binding protein in human and murine tissues

Abstract

A b s tra c t C ellular fatty acid-binding proteins (FABP) are a highly conserved fam ily of proteins consisting o f several subtypes» am ong them the m am m ary-derived growth inhibitor (M D G I) w hich is quite hom ologous to or even identical with the heart-type FABP (H-FABP). The FABPs and M D G I have been suggested to be in volved in intracellular fatty acid m etabolism and traffick ing. Recently, evidence for grow th and differentiation regulating properties of M D G I and H -FA B P was provid ed. U sing four affinity-purified polyclonal antibodies against bovine and hum an antigen preparations, the cel lular localization of M D G I/H -FA B P in hum an and mouse tissues and organs was studied. T he antibodies were weakly cross-reactive w ith adipose tissue extracts known to lack H-FABP, but failed to react by W estern blot analysis with liver-type FABP (L-FABP) and intesti nal-type FA B P (I-FABP). M D G I/H -FA B P protein was mainly detected in m yocardium , skeletal and sm ooth m uscle fibres, lipid and/or steroid synthesising cells (ad renals, Leydig cells, sebaceous glands, lactating m am mary gland) and term inally differentiated epithelia of the respiratory, intestinal and urogenital tracts. The results provide evidence that expression o f H -FA B P is associat ed with an irreversibly postm itotic and term inally differ entiated status of cells. Since all the antisera em ployed show ed spatially identical and qualitatively equal im m unostaining, it is suggested that hum an, bovine and m ouse M D G I/H -FA B P proteins share highly hom ologous epi topes.

Cell-type-specific regulation of genes involved in testicular lipid metabolism: fatty acid-binding proteins, diacylglycerol acyltransferases, and perilipin 2

“…The developmental profile of Fabp3 expression was consistent with this protein mostly localizing in Leydig cells (Heuckeroth et al 1987, Watanabe et al 1991, Zschiesche et al 1995 and with the fact that intratesticular testosterone concentrations (O'Shaughnessy et al 2002), as did Fabp3 (present results), showed a decline between P10 and P20, followed by an increase at P25. We confirmed that FABP3 protein was interstitially located and that it displayed low signal level at P6, decreased at P18, and was plentiful in adult testis (see Fig.…”

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

“…H-FABP was first shown to be released from injured myocardium in 1988, after which several studies investigated its application as a biochemical marker of myocardial injury. The H-FABP isoform is produced not only in cardiomyocytes but also, to a lesser extent, in skeletal muscle (23 ), distal tubular cells of the kidney (24 ), specific parts of the brain (25 ), lactating mammary glands, and placenta (23 ). Human H-FABP contains 132 amino acid residues and is an acidic protein (pI 5) (26 ).…”

“…In patients treated with standard thrombolytic therapy after AMI, plasma concentrations of H-FABP and myoglobin peaked at ϳ4 h after first symptoms, whereas creatine kinase (creatine phosphokinase or CK-MB) and lactate dehydrogenase peaked at ϳ12 and 20 h, respectively (52 ). Because H-FABP and myoglobin rapidly return to their respective URLs (within 24 h after AMI) as a result of renal clearance (23,52 ), both proteins can be used to assess a recurrent infarction within 10 h after first AMI (58 ), which might be missed by CK-MB, cTnT, and cTnI because plasma concentrations of these markers return much more slowly to reference (62 ). These differences in release kinetics do not impact the measurement of cardiac proteins in plasma, however (32,58,62 ).…”

Omega-3 Fatty Acids and a Novel Mammary Derived Growth Inhibitor Fatty Acid Binding Protein MRG in Suppression of Mammary Tumor

“…Furthermore, blocking antibody for MRG/B-FABP can block glial cell differentiation (31). MDGI/H-FABP protein has been detected mainly in myocardium, skeletal and smooth muscle fibers, lipid and steroidsynthesizing cells of adrenals, lactating mammary gland, and terminally differentiated epithelia of the respiratory, intestinal, and urogenital tracts (6). The results provide evidence that expression of MDGI is associated with an irreversibly postmitotic and terminally differentiated status of cells.…”