Observational Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jul 7, 2017; 23(25): 4604-4614
Published online Jul 7, 2017. doi: 10.3748/wjg.v23.i25.4604
Functional lipidomics in patients on home parenteral nutrition: Effect of lipid emulsions
Loris Pironi, Mariacristina Guidetti, Ornella Verrastro, Claudia Iacona, Federica Agostini, Caterina Pazzeschi, Anna Simona Sasdelli, Michele Melchiorre, Carla Ferreri
Loris Pironi, Mariacristina Guidetti, Ornella Verrastro, Claudia Iacona, Federica Agostini, Caterina Pazzeschi, Anna Simona Sasdelli, Chronic Intestinal Failure Center, Digestive Disease Department, St Orsola-Malpighi Hospital, 40138 Bologna, Italy
Michele Melchiorre, Lipinutragen Srl-Lipidomics Laboratory, 40100 Bologna, Italy
Carla Ferreri, ISOF, National Council of Research, 40100 Bologna, Italy
Author contributions: Pironi L was the guarantor and designed the study; Pironi L, Guidetti M and Ferreri C contributed equally to the work; Pironi L, Verrastro O, Iacona C, Agostini F, Pazzeschi C and Sasdelli AS performed the research; Melchiorre M contributed to the utilization of analytic tools and to data collection; Pironi L, Guidetti M and Ferreri C carried out the statistical analysis of the data and wrote the paper; all authors contributed to this manuscript.
Institutional review board statement: The study was reviewed and approved by the Ethics Committee of St Orsola-Malpighi University Hospital, Bologna, Italy.
Informed consent statement: All study participants, or their legal guardian representatives, provided informed written consent prior to study enrollment.
Conflict-of-interest statement: Prof. Loris Pironi has been a consultant for Baxter SpA, Shire SpA and BBraun SpA; Prof. Carla Ferreri is a co- founder of Lipinutragen srl, originating as a spin-off company officially recognised by the National Council of Research, Italy. Lipinutragen srl is concerned with the applications of membrane lipidomics regarding molecular diagnostics and health care, and participated in the study by paying the salary of one employee involved in the analyses and data collection (Michele Melchiorre). This does not alter the authors’ adherence to all policies of the World Journal of Gastroenterology as to sharing data and materials, which are unrestricted. No other competing interests of any nature (financial, non-financial, professional or personal) exist. Lipinutragen srl provided support in the form of a salary for Michele Mechiorre who was involved in GC-analysis of the FAs profile of IVLEs and of the RBC membrane, and in data collection, but did not have any additional role in the study design, decision to publish, or writing of the manuscript.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Loris Pironi, MD, PhD, Professor, Director, Chronic Intestinal Failure Center, Digestive Disease Department, St Orsola-Malpighi Hospital, Via Massarenti 9, 40138 Bologna, Italy. loris.pironi@unibo.it
Telephone: +39-51-6363073 Fax: +39-51-6363073
Received: December 16, 2016
Peer-review started: December 19, 2016
First decision: February 10, 2017
Revised: April 7, 2017
Accepted: June 1, 2017
Article in press: June 1, 2017
Published online: July 7, 2017
Abstract
AIM

To investigate the fatty acid-based functional lipidomics of patients on long-term home parenteral nutrition receiving different intravenous lipid emulsions.

METHODS

A cross-sectional comparative study was carried out on 3 groups of adults on home parenteral nutrition (HPN), receiving an HPN admixture containing an olive-soybean oil-based intravenous lipid emulsion (IVLE) (OO-IVLE; n = 15), a soybean- medium-chain triacylglycerol-olive-fish oil-based IVLE (SMOF-IVLE; n = 8) or HPN without IVLE (No-IVLE; n = 8) and 42 healthy controls (HCs). The inclusion criteria were: duration of HPN ≥ 3 mo, current HPN admixtures ≥ 2 mo and HPN infusions ≥ 2/wk. Blood samples were drawn 4-6 h after the discontinuation of the overnight HPN infusion. The functional lipidomics panel included: the red blood cell (RBC) fatty acid (FA) profile, molecular biomarkers [membrane fluidity: saturated/monounsaturated FA ratio = saturated fatty acid (SFA)/monounsaturated fatty acid (MUFA) index; inflammatory risk: n-6/n-3 polyunsaturated fatty acid (PUFA) ratio = n-6/n-3 index; cardiovascular risk: sum of n-3 eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) = n-3 index; free radical stress: sum of FA trans isomers = %trans index] and FA pathway enzyme activity estimate (delta-9-desaturase = D9D; delta-6-desaturase = D6D; delta-5-desaturase = D5D; elongase = ELO). Statistics were carried out using nonparametric tests. The amount of each FA was calculated as a percentage of the total FA content (relative%).

RESULTS

In the OO-IVLE group, the percentage of oleic acid in the RBCs was positively correlated with the weekly load of OO-IVLE (r = 0.540, P = 0.043). In the SMOF-IVLE cohort, the RBC membrane EPA and DHA were positively correlated with the daily amount of SMOF-IVLE (r = 0.751, P = 0.044) and the number of HPN infusions per week (r = 0.753; P = 0.046), respectively. The SMOF-IVLE group showed the highest EPA and DHA and the lowest arachidonic acid percentages (P < 0.001). The RBC membrane linoleic acid content was lower, and oleic and vaccenic acids were higher in all the HPN groups in comparison to the HCs. Vaccenic acid was positively correlated with the weekly HPN load of glucose in both the OO-IVLE (r = 0.716; P = 0.007) and the SMOF-IVLE (r = 0.732; P = 0.053) groups. The estimated activity of D9D was higher in all the HPN groups than in the HCs (P < 0.001). The estimated activity of D5D was lower in the SMOF-IVLE group than in the HCs (P = 0.013). The SFA/MUFA ratio was lower in all the HPN groups than in the HCs (P < 0.001). The n-6/n-3 index was lower and the n-3 index was higher in the SMOF-IVLE group in comparison to the HCs and to the other HPN groups (P < 0.001). The %trans index did not differ among the four groups.

CONCLUSION

The FA profile of IVLEs significantly influenced the cell membrane functional lipidomics. The amount of glucose in the HPN may play a relevant role, mediated by the insulin regulation of the FA pathway enzyme activities.

Keywords: Chronic intestinal failure, Home parenteral nutrition, Intravenous lipid emulsion, Cell membrane fatty acid profile, Cell membrane lipidome, Functional lipidomics

Core tip: Fatty acid-based “functional lipidomics” investigates the structural and functional roles played by lipids and their in vivo changes, and provides the rationalisation of these changes in connection with their biological significance. In this study, the effects of two intravenous lipid emulsions with different fatty acids profiles on the red blood cell membrane lipidome in patients on long-term home parenteral nutrition for chronic intestinal failure were investigated. The results were analysed in terms of functional lipidomics. The membrane lipidome was significantly modified by the fatty acid profile of the intravenous lipid emulsions. Functional lipidomics indicated that both the lipid emulsion fatty acid profile and the glucose amount of the parenteral nutrition admixture play a role in regulating the activity of the enzymes of the fatty acid metabolism pathways.