Protective effects of beta glucan in brain tissues of post-menopausal rats: a histochemical and ultra-structural study

Abstract

Decline of estrogen during menopause has been associated with numerous significant changes that have been linked to many pathophysiological complications. In addition, ovarian hormone deficiency increases the production of reactive oxygen radicals which could result in oxidative stress and cell damage. While estrogen therapy is often considered to overcome the behavioral and physiological shortcomings, antioxidants are gaining popularity for their beneficial property. For this purpose, in the present study, utilizing the antioxidant properties of beta glucan has been examined in treatment of menopause induced oxidative stress in cerebral neurons. Four groups of female Wistar rats were used: control, ovariectomy, ovariectomy + estrogen treated and ovariectomy + beta glucan treated. We observed a significant increase in neural degeneration in ovariectomized rats as compared to controls. Moreover, increased oxidative stress in the brains of the ovariectomized rats has been detected by performing immunohistochemical analysis. A large number of immuno-positive cerebral neurons have been observed in ovariectomy group rat brains. Interestingly, providing beta glucan treatment to ovariectomized rats reduced the number of degenerated neurons. Our study is the first to examine light and electron microscopic examination and immunohistochemical and stereological analysis of estrogen depletion in rats and to test protective role of beta glucan in the experimental study.

Chinese abstract

绝经期雌激素水平的降低与许多病理生理方面显著变化的并发症相关。此外，卵巢激素的缺乏会使活性氧自由基的生成增加，从而导致氧化应激和细胞损伤。所以雌激素治疗常常被认为能够克服这些行为和生理缺陷，抗氧化剂因其益处也在逐渐普及。出于这个目的，在目前的研究中，测定了β葡聚糖的抗氧化特性在人工绝经大鼠大脑神经元氧化应激方面的作用。雌性Wistar大鼠分四组：对照组，切除卵巢组，切除卵巢组+雌激素治疗组以及切除卵巢组+β葡聚糖治疗组。我们观察到，切除卵巢组的大鼠与对照组的大鼠相比，神经的退化明显增加。此外，在免疫组织化学分析发现，切除卵巢组大鼠脑的氧化应激增加了。在切除卵巢组的大鼠脑中发现了大量的免疫阳性脑神经元细胞。有趣的是，给予β葡聚糖治疗的切除卵巢的大鼠，它们的神经退化减少了。我们的研究是在对雌激素缺乏大鼠β葡聚糖的保护作用的实验性研究中第一次使用光电子显微镜和免疫组织化学检测以及形态计量分析的研究。

• Beta glucan
• brain
• menopause
• rat

Declaration of interest

There is no conflict of interest for all authors. Appropriate Institutional Review Board approval was obtained and procedures were used concerning animal subjects.