Protective effects of glutamine in a rat model of endotoxemia

The aim of this study was to characterize the protective effects of glutamine (Gln) on brain cells undergoing experimental endotoxemia induced by lipopolysaccharide (LPS) injection. Young rats were injected with LPS or control, and a subset of LPS-injected rats were pretreated with Gln. Electron microscopy and immunohistochemistry were used to visualize apoptosis and to determine distribution and expression of nuclear factor-κB (NF-κB), heat shock protein 70 (HSP70), platelet-derived growth factor-B (PDGF-B) and PDGF receptor-β (PDGFR-β). The levels of HSP70, PDGF-B and PDGFR-β in the rat brain were comparatively analyzed by western blotting. In a rat brain model of endotoxemia, Gln decreases the magnitude of apoptosis, upregulates the expression of HSP70 and inhibits the translocation of NF-κB from the cytoplasm to the nucleus. Gln upregulates PDGF-B and PDGFR-β expression in early and advanced sepsis. PDGF-B and PDGFR-β upregulation in the cerebral cortex are likely neuroprotective effects of Gln. We found that Gln is capable of regulating the immunological defense of local brain tissue, which provides a theoretical basis for using Gln to prevent and treat encephalopathy.