Toxicity of a soybean oil emulsion on human lymphocytes and neutrophils.
BACKGROUND
The incorporation of lipid emulsions in parenteral diets is a requirement for energy and essential fatty acid supply to critically ill patients. In this study, the toxicity of a lipid emulsion rich (60%) in triacylglycerol of omega-6 polyunsaturated fatty acids on leukocytes from healthy volunteers was investigated.


METHODS
Eleven volunteers were recruited, and blood samples were collected before infusion of a soybean oil emulsion, immediately afterwards, and 18 hours later. The cells were studied immediately after isolation and again after 24 hours or 48 hours in culture. The following determinations were made: composition and concentration of fatty acids in plasma, lymphocytes and neutrophils, lymphocyte proliferation, levels of cell viability, DNA fragmentation, phosphatidylserine externalization, mitochondrial depolarization, reactive oxygen species production, and neutral lipid accumulation.


RESULTS
Soybean oil emulsion decreased lymphocyte proliferation and provoked neutrophil and lymphocyte apoptosis and necrosis. Evidence is presented herein that soybean oil emulsion is less toxic to neutrophils than to lymphocytes. The mechanism of cell death induced by this oil emulsion was characterized by mitochondrial membrane depolarization and neutral lipid accumulation but did not alter reactive oxygen species production.


CONCLUSIONS
Soybean oil emulsion given as a single dose of 500 mL promotes lymphocyte and neutrophil death that may enhance the susceptibility of the patients to infections.
Cury-Boaventura
Maria Fernanda
MF
Department of Physiology and Biophysics, Institute of Biomedical Sciences, and the Division of Clinical Emergency, Faculty of Medicine, University of São Paulo, Av. Prof. Lineu Prestes 1524, CEP 05508-900 São Paulo, Brazil. mafecury@icb.usp.br
Gorjão
Renata
R
de Lima
Thaís Martins
TM
Piva
Tatiane Maria
TM
Peres
Carmem Maldonado
CM
Soriano
Francisco Garcia
FG
Curi
Rui
R
D000328:Adult; D017209:Apoptosis / Q000187:drug effects*; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D053938:DNA Fragmentation; D004594:Electrophysiology; D004655:Emulsions / Q000008:administration & dosage / Q000633:toxicity*; D005217:Fat Emulsions, Intravenous / Q000633:toxicity; D005227:Fatty Acids / Q000097:blood; D006801:Humans; D050356:Lipid Metabolism; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000187:drug effects* / Q000502:physiology / Q000648:ultrastructure; D008297:Male; D008928:Mitochondria / Q000502:physiology; D009504:Neutrophils / Q000187:drug effects* / Q000502:physiology / Q000648:ultrastructure; D010718:Phosphatidylserines / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D013024:Soybean Oil / Q000008:administration & dosage / Q000633:toxicity*
D004655:Emulsions; D005217:Fat Emulsions, Intravenous; D005227:Fatty Acids; D010718:Phosphatidylserines; D017382:Reactive Oxygen Species; D013024:Soybean Oil