Silva Maísa, Silva Marcelo E, de Paula Heberth, Carneiro Cláudia Martins, Pedrosa Maria Lucia
Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, 35400-000 Ouro Preto, MG, Brazil.
Nutr Res. 2008 Jun;28(6):391-8. doi: 10.1016/j.nutres.2008.02.009.
The objective of this study was to investigate the effect of iron overload with a hyperlipidemic diet on the histologic feature of hepatic tissue, the lipid and glycemic serum profiles, and the markers of oxidative damage and stress in a rat model. Twenty-four male Fischer rats, purchased from Experimental Nutrition Laboratory, Federal University of Ouro Preto, were assigned to 4 equal groups, 2 were fed a standard cholesterol-free diet (group C or control and CI or control with iron) containing 8.0% soybean oil and 2 were fed a hyperlipidemic diet (group H or hyperlipidemic and HI or hyperlipidemic with iron) containing 1.0% cholesterol and 25.0% soybean oil. A total of 50 mg of iron was administered to rats in groups CI and HI in 5 equal doses (1 every 3 weeks for a 16-week period) by intraperitoneal injections of 0.1 mL of iron dextran solution (100 g Fe(2+)/L; Sigma, St Louis, Mo). The other rats in groups C and H were treated in a similar manner but with sterile saline (0.1 mL). Irrespective of the diet, iron excess enhanced serum triacylglycerols (P < .05) and reduced serum glucose and glycated hemoglobin levels (P < .05) but did not affect serum cholesterol concentration. Histologic analysis showed steatosis in groups H and to a lesser extent in HI. No significant differences (P > .05) were observed in paraoxonase activities or in serum levels of free or total sulfhydryl radicals, malondialdehyde, or total antioxidants. The findings suggest that iron excess in the rat probably modifies lipid metabolism and, as a consequence, alters glucose homeostasis and increases the level of serum triacylglycerols but not of cholesterol.
本研究的目的是在大鼠模型中，研究高脂饮食引起的铁过载对肝组织组织学特征、血脂和血糖血清谱以及氧化损伤和应激标志物的影响。从乌罗普雷托联邦大学实验营养实验室购买的24只雄性Fischer大鼠被分为4组，每组6只。2组喂食标准无胆固醇饮食（C组或对照组和CI组或铁补充对照组），该饮食含有8.0%的大豆油；另外2组喂食高脂饮食（H组或高脂组和HI组或铁补充高脂组），该饮食含有1.0%的胆固醇和25.0%的大豆油。CI组和HI组的大鼠通过腹腔注射0.1 mL右旋糖酐铁溶液（100 g Fe(2+)/L；Sigma，圣路易斯，密苏里州），以5个相等剂量（每3周1次，共16周）给予总共50 mg铁。C组和H组的其他大鼠以类似方式用无菌生理盐水（0.1 mL）处理。无论饮食如何，铁过量均会提高血清三酰甘油水平（P < 0.05），降低血清葡萄糖和糖化血红蛋白水平（P < 0.05），但不影响血清胆固醇浓度。组织学分析显示，H组和HI组有脂肪变性，HI组程度较轻。对氧磷酶活性、血清游离或总巯基自由基、丙二醛或总抗氧化剂水平未观察到显著差异（P > 0.05）。研究结果表明，大鼠体内铁过量可能会改变脂质代谢，进而改变葡萄糖稳态，增加血清三酰甘油水平，但不会增加胆固醇水平。
