Ho D Y, Saydam T C, Fink S L, Lawrence M S, Sapolsky R M
Department of Biological Sciences, Stanford University, CA 94305-5120, USA.
J Neurochem. 1995 Aug;65(2):842-50. doi: 10.1046/j.1471-4159.1995.65020842.x.
Because neurons are postmitotic, they are irreplaceable once they succumb to necrotic insults such as hypoglycemia, ischemia, and seizure. A paucity of energy can exacerbate the toxicities of these insults; thus, a plausible route to protect neurons from necrotic injury would be to enhance their glucose uptake capability. We have demonstrated previously that defective herpes simplex virus (HSV) vectors overexpressing the rat brain glucose transporter (GT) gene (gt) can enhance glucose uptake in adult rat hippocampus and in hippocampal cultures. Furthermore, we have observed that such vectors can maintain neuronal metabolism during hypoglycemia and reduce kainic acid-induced seizure damage. In this study, we have developed bicistronic vectors that coexpressed gt and Escherichia coli lacZ as a reporter gene, which allows us to identify directly neurons that are infected with the vectors. Overexpression of GT from these vectors protected cultured hippocampal, spinal cord, and septal neurons against various necrotic insults, including hypoglycemia, glutamate, and 3-nitropropionic acid. Our observations demonstrate the feasibility of using HSV vectors to protect neurons from necrotic insults. Although this study has concentrated on the delivery of gt, other genes with therapeutic or protective capability might also be used.
由于神经元处于有丝分裂后阶段,一旦它们因诸如低血糖、缺血和癫痫发作等坏死性损伤而死亡,就无法被替代。能量匮乏会加剧这些损伤的毒性;因此,保护神经元免受坏死性损伤的一个合理途径是增强它们的葡萄糖摄取能力。我们之前已经证明,过表达大鼠脑葡萄糖转运体(GT)基因(gt)的缺陷型单纯疱疹病毒(HSV)载体能够增强成年大鼠海马体以及海马体培养物中的葡萄糖摄取。此外,我们观察到此类载体能够在低血糖期间维持神经元代谢,并减少海藻酸诱导的癫痫损伤。在本研究中,我们构建了共表达gt和大肠杆菌lacZ作为报告基因的双顺反子载体,这使我们能够直接鉴定出被该载体感染的神经元。这些载体中GT的过表达保护了培养的海马体、脊髓和隔区神经元免受包括低血糖、谷氨酸和3-硝基丙酸在内的各种坏死性损伤。我们的观察结果证明了使用HSV载体保护神经元免受坏死性损伤的可行性。尽管本研究集中于gt的递送,但其他具有治疗或保护能力的基因或许也可被利用。