Effect of olive oil-based emulsion on human lymphocyte and neutrophil death.
BACKGROUND
The incorporation of lipid emulsions in parenteral diets is a requirement for energy and essential fatty acid supply to critically ill patients. The most frequently used IV lipid emulsions (LE) are composed with long-chain triacylglycerols rich in omega-6 polyunsaturated fatty acids (PUFA) from soybean oil, but these LE promote lymphocyte and neutrophil death. A new emulsion containing 20% soybean oil and 80% olive oil rich in omega-9 monounsaturated fatty acids (MUFA) has been hypothesized not to cause impairment of immune function. In this study, the toxicity of an olive oil-based emulsion (OOE) on lymphocytes and neutrophils from healthy volunteers was investigated.


METHODS
Twenty volunteers were recruited and blood was collected before a 6-hour infusion of an OOE, immediately after infusion, and again 18 hours postinfusion. Lymphocytes and neutrophils were isolated by gradient density. The cells were studied immediately after isolation and after 24 hours or 48 hours in culture. The following determinations were carried out: triacylglycerol levels and fatty acid composition and levels in plasma, lymphocyte proliferation, production of reactive oxygen species, and parameters of lymphocyte and neutrophil death (viability, DNA fragmentation, phosphatidylserine externalization, mitochondrial depolarization, and neutral lipid accumulation).


RESULTS
OOE decreased lymphocyte proliferation, provoked lymphocyte necrosis, and had no effect on the proportion of viable neutrophils. The mechanism of cell death induced by OOE involved neutral lipid accumulation but had no effect on mitochondrial membrane depolarization.


CONCLUSIONS
The OOE given as a single dose of 500 mL induced low toxicity to lymphocytes from healthy volunteers, probably by necrosis.
Cury-Boaventura
Maria Fernanda
MF
Post-Graduate Program in Human Movement Science, Biological Sciences and Health Center, Cruzeiro do Sul University, São Paulo, Brazil. mafecury@icb.usp.br
Gorjão
Renata
R
de Lima
Thaís Martins
TM
Fiamoncini
Jarlei
J
Torres
Rosângela Pavan
RP
Mancini-Filho
Jorge
J
Soriano
Francisco Garcia
FG
Curi
Rui
R
D000328:Adult; D017209:Apoptosis / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D053938:DNA Fragmentation; D005217:Fat Emulsions, Intravenous / Q000737:chemistry; D006801:Humans; D050356:Lipid Metabolism / Q000187:drug effects / Q000502:physiology; D008213:Lymphocyte Activation; D008214:Lymphocytes / Q000187:drug effects* / Q000502:physiology; D008297:Male; D008928:Mitochondria / Q000378:metabolism; D009504:Neutrophils / Q000187:drug effects* / Q000502:physiology; D000069463:Olive Oil; D010288:Parenteral Nutrition / Q000379:methods*; D010938:Plant Oils / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D013024:Soybean Oil / Q000494:pharmacology
D005217:Fat Emulsions, Intravenous; D000069463:Olive Oil; D010938:Plant Oils; D017382:Reactive Oxygen Species; D013024:Soybean Oil