Concentrations of very long-chain fatty acid in whole blood are associated with cardiovascular risk factors in children

Fatty acid analysis in serum of patients with elevated lipoprotein(a) and cardiovascular disease undergoing lipoprotein apheresis

BACKGROUND

Lipoprotein apheresis (LA) is an extracorporeal treatment that transiently reduces lipoprotein (a) [Lp(a)] by 60% and leads to an 80-92% reduction in major adverse cardiovascular events. LA has a significant impact on lipid profile in serum of patients with atherosclerotic cardiovascular disease.

OBJECTIVE

To investigate the effects of LA on the composition of serum fatty acids (FAs), focusing on those which could have an impact on cardiovascular disease (CVD).

METHODS

This is a prospective study in the First Department of Cardiology of the Medical University of Gdansk, Poland. Serum samples were collected from 28 patients before LA, just after the procedure, and 7 days after LA. Additionally, in a smaller group of patients, the samples were collected after a second tour of LA (2 weeks later), as well as after 1 year from the first procedure. The serum FA profile was analyzed using gas chromatography-mass spectrometry.

RESULTS

After the LA procedure, a substantial change in serum FA composition along with low-density lipoprotein cholesterol (LDL-C) and Lp(a) decrease were observed 7 days after procedure, but these parameters returned to the values similar to those before procedure after 14 days. Very long-chain FAs (VLCFAs) and very long-chain monounsaturated FAs (VLC-MUFAs) were eluted at 57% and remained low even 7 days after LA (p=0.027 and p < 0.001, respectively). We also observed an increase in the percentage of total branched-chain FAs (BCFAs) (p=0.004) and anteiso BCFAs (p=0.012) after LA. After 1 year of regular LA, a substantial decrease in serum VLC-MUFAs and n3 polyunsaturated LA (PUFAs) were noted.

CONCLUSIONS

Decreased VLCFAs and VLC-MUFAs involved in CVD development remained low even 7 days after LA. An acute increase in the levels of anti-inflammatory BCFAs was observed. In turn long-term regular administration of LA substantially decreased VLC-MUFA and n3 PUFA.

Hyper-Elongation in Colorectal Cancer Tissue - Cerotic Acid is a Potential Novel Serum Metabolic Marker of Colorectal Malignancies

BACKGROUNDS/AIMS

Colorectal cancer (CRC) cells show some alterations of lipid metabolism. Elongation of fatty acids (FA) has not been studied in CRC tissues thus far. The aim of this study was to verify if CRC specimens and normal colon mucosa differ in terms of their levels of very long-chain FAs, a product of FA elongation. Moreover, the expression of elongase genes has been studied in normal tissue and CRC. Finally, we searched for some specific products of FA elongation in serum of CRC patients.

METHODS

The specimens of normal colon mucosa and CRC were obtained from nineteen CRC patients differ in terms of FA elongation. We also searched for some specific products of FA elongation in serum of CRC patients and from healthy volunteers. Tissue and serum FA profiles were determined by means of gas chromatography-mass spectrometry (GC/MS), and the tissue expression of elongases (ELOVLs) was analyzed with real-time PCR.

RESULTS

Compared to normal colon tissue, CRC specimens showed significantly higher levels of 22-, 24- and 26-carbon FAs, stronger expressions of ELOVL1 and ELOVL6 (4- and 9-fold elevated respectively), and higher values of 18: 0/16: 0 elongation index. We also demonstrated presence of cerotic acid (26: 0) in serum of all CRC patients but in none of the healthy controls.

CONCLUSIONS

CRC tissue seems to be characterized by enhanced FA elongation (hyper-elongation). Presence of cerotic acid in CRC patients sera and absence of this FA in healthy subjects points to this compound as a strong candidate for specific metabolic marker of colorectal malignancies.