Department of Nutritional Sciences, The Pennsylvania State University, University Park, PA, USA.
J Nutr. 2013 Mar;143(3):253-9. doi: 10.3945/jn.112.169797. Epub 2013 Jan 16.
The accumulation of hepatic TG and development of hepatic steatosis (HS) is a serious complication of the use of parenteral nutrition (PN) formulas containing a high percentage of dextrose. But whether fat emulsions or other nutrients can ameliorate the induction of HS by high-carbohydrate diets is still uncertain. We hypothesized that administration of a lipid emulsion (LE; Intralipid) and/or the vitamin A metabolite retinal (RAL) will reduce hepatic TG accumulation and attenuate indicators of inflammation. C57BL/6 male mice were fed PN formula as their only source of hydration and nutrition for 4-5 wk. In Expt. 1, mice were fed PN only or PN plus treatment with RAL (1 μg/g orally), LE (200 μL i.v.), or both LE and RAL. In Expt. 2, LE was orally administered at 4 and 13.5% of energy to PN-fed mice. All PN mice developed HS compared with mice fed normal chow (NC) and HS was reduced by LE. The liver TG mass was lower in the PN+LE and PN+RAL+LE groups compared with the PN and PN+RAL groups (P < 0.01) and in the 4% and 13.5% PN+LE groups compared with PN alone. Hepatic total retinol was higher in the RAL-fed mice (P < 0.0001), but RAL did not alter TG mass. mRNA transcripts for fatty acid synthase (Fasn) and sterol regulatory element-binding protein-1c (Srebpf1) were higher in the PN compared with the NC mice, but FAS protein and Srebpf1 mRNA were lower in the PN+LE groups compared with PN alone. The inflammation marker serum amyloid P component was also reduced. In summary, LE given either i.v. or orally may be sufficient to reduce the steatotic potential of orally fed high-dextrose formulas and may suppress the early development of HS during PN therapy.
肝脏甘油三酯(TG)的积累和肝脂肪变性(HS)的发展是使用含有高比例葡萄糖的肠外营养(PN)配方的严重并发症。但是,脂肪乳剂或其他营养素是否可以改善高碳水化合物饮食引起的 HS 尚不确定。我们假设给予脂肪乳剂(LE;Intralipid)和/或维生素 A 代谢产物视黄醛(RAL)将减少肝 TG 积累并减轻炎症指标。C57BL/6 雄性小鼠仅接受 PN 配方作为其水合和营养的唯一来源,持续 4-5 周。在实验 1 中,小鼠接受 PN 配方治疗或 PN 配方联合 RAL(1μg/g 口服)、LE(200μL 静脉内)或 LE 和 RAL 联合治疗。在实验 2 中,将 LE 以 4%和 13.5%的能量口服给予接受 PN 喂养的小鼠。与接受正常饮食(NC)的小鼠相比,所有接受 PN 的小鼠均发生 HS,而 LE 可减轻 HS。与 PN 组和 PN+RAL 组相比,PN+LE 组和 PN+RAL+LE 组的肝 TG 质量更低(P<0.01),与单独接受 PN 的组相比,4%和 13.5%PN+LE 组的肝 TG 质量更低(P<0.01)。接受 RAL 喂养的小鼠肝总视黄醇较高(P<0.0001),但 RAL 并未改变 TG 质量。与 NC 组相比,PN 组的脂肪酸合酶(Fasn)和固醇调节元件结合蛋白-1c(Srebpf1)的 mRNA 转录物更高,但与单独接受 PN 的组相比,PN+LE 组的 FAS 蛋白和 Srebpf1 mRNA 较低。炎症标志物血清淀粉样蛋白 P 成分也减少。总之,静脉内或口服给予 LE 可能足以降低口服高葡萄糖配方的脂肪变性潜力,并可能在 PN 治疗期间抑制 HS 的早期发展。