Zornoff Leonardo A M, Matsubara Luiz S, Matsubara Beatriz B, Okoshi Marina P, Okoshi Katashi, Dal Pai-Silva Maeli, Carvalho Robson F, Cicogna Antonio C, Padovani Carlos R, Novelli Ethel L, Novo Rosangela, Campana Alvaro O, Paiva Sergio A R
Departamento de Clínica Médica, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista (UNESP), Botucatu, Brazil.
Toxicol Sci. 2006 Mar;90(1):259-66. doi: 10.1093/toxsci/kfj080. Epub 2005 Dec 30.
The objectives were to analyze the cardiac effects of exposure to tobacco smoke (ETS), for a period of 30 days, alone and in combination with beta-carotene supplementation (BC).
Rats were allocated into: Air (control, n = 13); Air + BC (n = 11); ETS (n = 11); and BC + ETS (n = 9). In Air + BC and BC + ETS, 500 mg of BC were added to the diet. After three months of randomization, cardiac structure and function were assessed by echocardiogram. After that, animals were euthanized and morphological data were analyzed post-mortem. One-way and two-way ANOVA were used to assess the effects of ETS, BC and the interaction between ETS and BC on the variables.
ETS presented smaller cardiac output (0.087 +/- 0.001 vs. 0.105 +/- 0.004 l/min; p = 0.007), higher left ventricular diastolic diameter (19.6 +/- 0.5 vs. 18.0 +/- 0.5 mm/kg; p = 0.024), higher left ventricular (2.02 +/- 0.05 vs. 1.70 +/- 0.03 g/kg; p < 0.001) and atrium (0.24 +/- 0.01 vs. 0.19 +/- 0.01 g/kg; p = 0.003) weight, adjusted to body weight of animals, and higher values of hepatic lipid hydroperoxide (5.32 +/- 0.1 vs. 4.84 +/- 0.1 nmol/g tissue; p = 0.031) than Air. However, considering those variables, there were no differences between Air and BC + ETS (0.099 +/- 0.004 l/min; 19.0 +/- 0.5 mm/kg; 1.83 +/- 0.04 g/kg; 0.19 +/- 0.01 g/kg; 4.88 +/- 0.1 nmol/g tissue, respectively; p > 0.05). Ultrastructural alterations were found in ETS: disorganization or loss of myofilaments, plasmatic membrane infolding, sarcoplasm reticulum dilatation, polymorphic mitochondria with swelling and decreased cristae. In BC + ETS, most fibers showed normal morphological aspects.
One-month tobacco-smoke exposure induces functional and morphological cardiac alterations and BC supplementation attenuates this ventricular remodeling process.
本研究旨在分析接触烟草烟雾（ETS）30天单独及联合补充β-胡萝卜素（BC）对心脏的影响。
将大鼠分为：空气组（对照组，n = 13）；空气+BC组（n = 11）；ETS组（n = 11）；BC + ETS组（n = 9）。在空气+BC组和BC + ETS组中，在饮食中添加500毫克BC。随机分组三个月后，通过超声心动图评估心脏结构和功能。之后，对动物实施安乐死并在死后分析形态学数据。采用单因素和双因素方差分析评估ETS、BC以及ETS与BC之间的相互作用对各变量的影响。
与空气组相比，ETS组的心输出量较小（0.087±0.001对0.105±0.004升/分钟；p = 0.007），左心室舒张直径较大（19.6±0.5对18.0±0.5毫米/千克；p = 0.024），左心室（2.02±0.05对1.70±0.03克/千克；p < 0.001）和心房（0.24±0.01对0.19±0.01克/千克；p = 0.003）重量（按动物体重调整）较高，肝脂质过氧化氢值也较高（5.32±0.1对4.84±0.1纳摩尔/克组织；p = 0.031）。然而，就这些变量而言，空气组与BC + ETS组之间无差异（分别为0.099±0.004升/分钟；19.0±0.5毫米/千克；1.83±0.04克/千克；0.19±0.01克/千克；4.88±0.1纳摩尔/克组织；p > 0.05）。在ETS组中发现超微结构改变：肌丝紊乱或缺失、质膜内陷、肌浆网扩张、线粒体多形性伴肿胀和嵴减少。在BC + ETS组中，大多数纤维显示正常形态学特征。
暴露于烟草烟雾一个月可引起心脏功能和形态学改变，补充BC可减轻这种心室重塑过程。
