Effects of linoleic and gamma-linolenic acids (efamol evening primrose oil) on fatty acid-binding proteins of rat liver

Plant-Derived Nutraceuticals and Immune System Modulation: An Evidence-Based Overview

Immunomodulators are agents able to affect the immune system, by boosting the immune defences to improve the body reaction against infectious or exogenous injuries, or suppressing the abnormal immune response occurring in immune disorders. Moreover, immunoadjuvants can support immune system acting on nonimmune targets, thus improving the immune response. The modulation of inflammatory pathways and microbiome can also contribute to control the immune function. Some plant-based nutraceuticals have been studied as possible immunomodulating agents due to their multiple and pleiotropic effects. Being usually more tolerable than pharmacological treatments, their adjuvant contribution is approached as a desirable nutraceutical strategy. In the present review, the up to date knowledge about the immunomodulating properties of polysaccharides, fatty acids and labdane diterpenes have been analyzed, in order to give scientific basic and clinical evidence to support their practical use. Since promising evidence in preclinical studies, limited and sometimes confusing results have been highlighted in clinical trials, likely due to low methodological quality and lacking standardization. More investigations of high quality and specificity are required to describe in depth the usefulness of these plant-derived nutraceuticals in the immune system modulation, for health promoting and disease preventing purposes.

Purification and characterization of fatty acid-binding proteins from brown adipose tissue of the rat

Fatty acid-binding proteins (FABPs) have been identified and purified from interscapular brown adipose tissue of the rat. The proteins were characterized and their properties compared with the FABP present in white adipose tissue. FABP was purified to electrophoretic homogeneity from brown adipose tissue by a procedure involving precipitation with 70% ammonium sulphate, followed sequentially by ion-exchange chromatography and gel filtration chromatography. The purified fraction migrated as a single band on SDS-PAGE with an apparent molecular mass of 14,200. Scatchard analysis of [14C]oleate-binding to purified FABP gave a Kd value of approx. 0.80 +/- 0.02 microM and a maximal binding of 0.65 +/- 0.03 mol per mol of protein; these values were similar to that found with the FABP purified from white fat. The FABP concentration in brown adipose tissue was almost twice that of FABP in white adipose tissue. Fatty acid analysis of FABP from brown adipose tissue revealed that the intrinsic arachidonic acid content was proportionately higher than that present in FABP of white adipose tissue. Isoelectric focusing of delipidated FABP indicated that it existed with two charge isoforms (pI 6.85 and 7.35). The purified FABP additionally emerged in two peaks (FABP-I and FABP-II) from a reverse phase HPLC column. Amino acid analysis showed that Gly, Thr, and Ser residues in FABP-I were almost twice as high as in FABP-II. The N-terminals of both FABP-I and -II were not blocked. These components have been partially sequenced and showed a sequence homology only between 25-31 residues from the N-terminal. Further studies are required to elucidate the precise function of the two different isoforms of FABP in brown adipose tissue.