Glutamate reduces experimental intestinal hyperpermeability and facilitates glutamine support of gut integrity

AIM:To assess whether glutamate plays a similar role to glutamine in preserving gut wall integrity.METHODS:The effects of glutamine and glutamate on induced hyperpermeability in intestinal cell lines were studied.Paracellular hyperpermeability was induced in Caco2.BBE and HT-29CL.19A cell lines by adding phorbol-12,13-dibutyrate(PDB) apically,after which the effects of glutamine and glutamate on horseradish peroxidase(HRP) diffusion were studied.An inhibitor of glutamate transport(L-trans-pyrrolidine-2,4-dicarboxylic acid:trans-PDC) and an irreversible blocker(acivicin) of the extracellular glutamine to glutamate converting enzyme,γ-glutamyltransferase,were used.RESULTS:Apical to basolateral HRP flux increased significantly compared to controls not exposed to PDB (n=30,P<0.001).Glutamine application reduced hyperpermeability by 19%and 39%in the respective cell lines.Glutamate application reduced hyperpermeability by 30%and 20%,respectively.Incubation of HT29CL.19A cells with acivicin and subsequent PDB and glutamine addition increased permeability levels.Incubation of Caco2.BBE cells with trans-PDC followed by PDB and glutamate addition also resulted in high permeability levels.CONCLUSION:Apical glutamate-similar to glutaminecan decrease induced paracellular hyperpermeability.Extracellular conversion of glutamine to glutamate and subsequent uptake of glutamate could be a pivotal step in the mechanism underlying the protective effect of glutamine.

现代民用建筑设计中的节能设计技术

把节能设计引入到现代民用建筑设计中具有重要的意义。不仅让资源得到有效的利用,同时还有效的控制了施工的成本、让工程的效益最大限度的提升。在今后对民用建筑设计的时候,为了让建筑节能技术更好的使用,就需要根据项目的实际情况,采取相应的措施,做好节能设计工作。笔者在本文中对现代建筑设计中的节能设计技术进行了深入的分析以便于提高房屋节能施工的效果。