Department of Comparative Medicine, Oregon Health and Science University, Portland, OR 97239, USA.
Lab Anim. 2010 Jul;44(3):238-46. doi: 10.1258/la.2009.009031. Epub 2010 Feb 10.
Oestrogen administration can alter experimental stroke outcomes. Soy as a source of phytoestrogens may therefore modulate responses in 'oestrogen-sensitive' stroke models, thus potentially confounding results. We evaluated the effects of dietary soy on acute infarct volumes in a pilot study using a rat focal stroke model. We hypothesized that ovariectomized (OVX) rats fed a soy-rich diet would have smaller acute infarct volumes than rats fed a soy-free diet. OVX rats were randomly assigned to a soy-free (n = 6) or a soy-rich (n = 6) diet for four weeks and weighed weekly. Following the dietary trial, rats underwent 2 h of middle cerebral artery occlusion (MCAO). Mean arterial blood pressure, rectal and temporalis muscle temperatures, arterial blood gases and blood glucose were recorded peri-ischaemia. Rats were euthanized 22 h following 2 h of MCAO. Brains were stained with 2,3,5-triphenyl tetrazolium chloride for acute infarct volume analysis. Uterine weight and histology were also evaluated as additional internal oestrogen-sensitive controls. Rats on the soy-free diet had greater gains in body weight (259 +/- 6% baseline body weight) than rats on the soy-rich diet (238 +/- 4% baseline body weight). No differences were seen in uterine weight and histology, peri-ischaemic physiological parameters and infarct volumes between the treatment groups. The results of this pilot study suggest that the dietary soy level tested may not alter acute infarct volumes in ischaemic female rat brain. More studies addressing the potential confounding effects of dietary soy in 'oestrogen-sensitive' stroke models are needed if investigators are to make informed choices regarding diets used in experimental stroke research.
雌激素的给予可以改变实验性中风的结果。因此，大豆作为植物雌激素的来源可能会调节“雌激素敏感”中风模型中的反应，从而潜在地干扰结果。我们使用大鼠局灶性中风模型评估了饮食大豆对急性梗死体积的影响。我们假设，给予富含大豆的饮食的去卵巢（OVX）大鼠的急性梗死体积将小于给予无大豆饮食的大鼠。OVX 大鼠被随机分配到无大豆（n = 6）或富含大豆（n = 6）饮食中，每周称重一次。在饮食试验后，大鼠进行 2 小时大脑中动脉闭塞（MCAO）。记录缺血期间的平均动脉血压、直肠和颞肌温度、动脉血气和血糖。MCAO 后 2 小时，大鼠被安乐死。用 2,3,5-三苯基氯化四氮唑对大脑进行染色，以分析急性梗死体积。还评估了子宫重量和组织学作为额外的内部雌激素敏感对照。给予无大豆饮食的大鼠体重增加（基线体重的 259 +/- 6%）大于给予富含大豆饮食的大鼠（基线体重的 238 +/- 4%）。治疗组之间在子宫重量和组织学、缺血期间的生理参数和梗死体积方面没有差异。这项初步研究的结果表明，所测试的饮食大豆水平可能不会改变缺血雌性大鼠大脑中的急性梗死体积。如果研究人员要对实验性中风研究中使用的饮食做出明智的选择，那么需要进行更多的研究来解决饮食大豆对“雌激素敏感”中风模型的潜在混杂影响。
