Endotoxin and cytokine released during parenteral nutrition.
BACKGROUND
Apart from its benefits, parenteral nutrition (PN)-related complications have been reported. Studies have shown that PN could alter cytochrome P450 (CYP) activity. One of the possible mechanisms is through cytokine and nitrite release, which is triggered by endotoxin. The purpose of this study is to investigate the potential release of endotoxin, cytokines, and nitrite during PN.


METHODS
Rats were randomly assigned into either (a) the PN group, which received continuous PN infusion only; or (b) the control group, which received normal chow with saline infusion. The infusions were administered continuously for 7 days, and then blood was collected and microsomes were prepared from the excised livers.


RESULTS
Endotoxin levels in the PN group were significantly higher in portal vein but not in inferior vena cava when compared with those of the controls. TNF-alpha and IL-6 levels were significantly higher in the PN group (p < .05). However, IL-1 beta levels were not significantly different in the 2 groups (p > .05). The nitrite levels, the end product of nitric oxide formation, were found to be almost 2 times higher after PN (p < .05).


CONCLUSIONS
It is confirmed that a 7-day infusion treatment of PN in rat may be linked to bacterial translocation, which leads to increased levels of endotoxin. This increase could trigger cytokine release, which could down regulate CYP activities.
Zheng
Yi J
YJ
Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta, Canada.
Tam
Yun K
YK
Coutts
Ronald T
RT
D000818:Animals; D018988:Bacterial Translocation; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D016207:Cytokines / Q000378:metabolism*; D004731:Endotoxins / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic; D007375:Interleukin-1 / Q000096:biosynthesis; D015850:Interleukin-6 / Q000096:biosynthesis; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism* / Q000473:pathology; D009573:Nitrites / Q000378:metabolism; D010288:Parenteral Nutrition / Q000009:adverse effects*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
D016207:Cytokines; D004731:Endotoxins; D007375:Interleukin-1; D015850:Interleukin-6; D009573:Nitrites; D014409:Tumor Necrosis Factor-alpha; D003577:Cytochrome P-450 Enzyme System