Beltramini Mariano, Zambenedetti Pamela, Raso Michelangelo, IbnlKayat Meryem Idrissi, Zatta Paolo
Department of Biology, University of Padova, and Pathology Division and the Brain Bank, General Hospital, Dolo-Venezia, Italy.
Brain Res. 2006 Sep 13;1109(1):207-18. doi: 10.1016/j.brainres.2006.06.108. Epub 2006 Aug 9.
Streptozotocin is a natural antibiotic produced by Streptomyces achromogenes able to induce diabetes in experimental animals. Among various toxic properties, streptozotocin is a potent source for reactive oxygen species. In this paper, we report the biological response of brain, upon treatment with streptozotocin in terms of metal ions dismetabolism and metallothionein expression. In addition, important information on the preventive effect of zinc in eliciting the pharmacological effect of the drug are reported, in relation to the effective role of the metal ions in inducing metallothionein synthesis. In the brain, streptozotocin treatment affects mostly the hippocampus and cerebellum as shown by a high GAFP and MT-I-II immunopositivity of glial cells. The Zn pre-treatment reduces significantly, as a general effect, the occurrence of hyperglycaemic status. At the brain level, the observed astrocytosis is strongly reduced. The high inducibility of MT represents a rapid and convenient response able to prevent the deleterious effects consequent to the oxidative stress. All together these results support the efficacy of the Zn treatment in order to prevent streptozotocin effects, including brain tissues.
链脲佐菌素是由产色链霉菌产生的一种天然抗生素，能够在实验动物中诱发糖尿病。在各种毒性特性中，链脲佐菌素是活性氧的一个重要来源。在本文中，我们报告了用链脲佐菌素处理后大脑在金属离子代谢紊乱和金属硫蛋白表达方面的生物学反应。此外，还报告了有关锌在引发药物药理作用方面的预防作用的重要信息，这与金属离子在诱导金属硫蛋白合成中的有效作用有关。在大脑中，链脲佐菌素处理主要影响海马体和小脑，这表现为神经胶质细胞的高谷胱甘肽还原酶相关蛋白（GAFP）和金属硫蛋白-I-II免疫阳性。锌预处理总体上显著降低了高血糖状态的发生。在大脑水平上，观察到的星形细胞增生明显减少。金属硫蛋白的高诱导性代表了一种快速且便捷的反应，能够预防氧化应激带来的有害影响。所有这些结果都支持锌处理在预防链脲佐菌素作用（包括对脑组织的作用）方面的有效性。
