linoleic-acid and Uremia

Protein-bound uremic toxins (PBUTs) and liver failure-related cholestatic solutes are associated with adverse outcomes in patients with chronic kidney disease (CKD) and liver failure, respectively, and are not easily removed by traditional dialysis therapies. We constructed linoleic acid-modified liposomes (LA-liposomes) as indirect adsorbent in the dialysate, and evaluated their effects on the clearance of the representative PBUTs and cholestatic solutes.. The LA-liposomes were prepared by the thin-film hydration method. The binding rates of liposomes and protein-bound solutes were detected by the ultrafiltration column. The in vitro dialysis experiments were performed using both non-current and current devices to assay the clearing efficiency of the dialysate supported by LA-liposomes.. The LA-liposomes exhibited good binding properties to the PBUTs, bilirubin and bile acids. The LA-liposome dialysate showed higher solute reduction rates of the representative PBUTs and cholestatic solutes than the traditional dialysate or dialysate supported by the unmodified plain liposomes. Also, albumin binding of the PBUTs was significantly inhibited by the addition of linoleic acid (LA), and the removal efficiency of PBUTs was greatly enhanced by the combination of indirect adsorbent LA-liposomes and LA as the competitive displacer.. LA-liposomes were efficient in the clearance of the representative PBUTs and liver failure-related solutes. Moreover, the combination of indirect adsorbent LA-liposomes and competitive displacer suggested a potential application for the extremely highly-bound solutes.

Topics: Dialysis Solutions; Humans; Linoleic Acid; Liposomes; Protein Binding; Renal Dialysis; Toxins, Biological; Uremia

An optimized method based on GC-MS with ethyl chloroformate derivatization has been developed for the comprehensive analysis of endogenous metabolites in serum. Twenty-two reference standards and serum samples were used to validate the proposed method. The correlation coefficient was higher than 0.9900 for each of the standards, and the LOD varied from 125 to 300 pg on-column. The analytical equipment exhibited good repeatability (RSD<10%) for all of the standards. Both the repeatability and the within-48-h stability of the analytical method were satisfactory (RSD<10%) for the 18 metabolites identified in the serum samples. Mean recovery was acceptable for the 18 metabolites, ranging from 70% to 120% with RSDs of less than 10%. Using the optimized protocol and a subsequent multivariate statistical technique, complete differentiation was achieved between the metabolic profile of uremic patients and that of age- and sex-matched normal subjects. Significantly decreased levels of valine, leucine, and isoleucine and increased levels of myristic acid and linoleic acid were observed in the patient group. This work demonstrated that this method is suitable for serum-based metabolic profiling studies.

Topics: Formic Acid Esters; Gas Chromatography-Mass Spectrometry; Humans; Isoleucine; Leucine; Linoleic Acid; Myristic Acid; Reference Standards; Reproducibility of Results; Uremia; Valine

Three groups of patients with chronic renal failure (CRF), 16 non-dialyzed, 16 undergoing haemodialysis (HD), 16 undergoing continuous ambulatory peritoneal dialysis (CAPD), and 48 controls were examined. We analyzed the fatty acid composition in membranes from erythrocytes and platelets and the platelet malondialdehyde (MDA) production as an index of thromboxane metabolism. Marked differences in erythrocytes fatty acid composition were observed between patients with CRF and controls and, particularly, among the three groups of patients with CRF. Patients on CAPD were characterized by an increase in oleic acid, while haemodialyzed had a marked increase in arachidonic acid. Platelet fatty acid composition showed similar differences, suggesting a 'systemic' membrane abnormality. Platelet MDA was increased in haemodialyzed and positively correlated with the platelet arachidonate content.

Topics: Adult; Aged; Aged, 80 and over; Arachidonic Acid; Blood Platelets; Cell Membrane; Erythrocyte Membrane; Fatty Acids; Fatty Acids, Monounsaturated; Fatty Acids, Unsaturated; Female; Humans; Linoleic Acid; Linoleic Acids; Male; Malondialdehyde; Middle Aged; Oleic Acid; Oleic Acids; Peritoneal Dialysis, Continuous Ambulatory; Renal Dialysis; Uremia