[Mechanism of glutamine downregulates the cytokine expression in lipopolysaccharide-stimulated human peripheral blood mononuclear cells].
OBJECTIVE
To investigate the mechanism that glutamine (Gln) downregulates the cytokine expression in lipopolysaccharide (LPS)-stimulated human peripheral blood mononuclear cells (PMBCs).


METHODS
PMBCs were extracted from healthy volunteer by density gradient centrifugation, the cells were divided into two parts. The first part of PMBCs was pretreated with Gln of the concentration of 0, 8, 15 mmol/L for 0.5 h and 2.0 h respectively, then stimulated by LPS for 4.0 h. Cells and supernatants were collected. The second part of PBMCs was divided into group A, B and C. Group A and B were pretreated with HSP70 blocker (Quercetin) for 1.0 h, then were stimulated by LPS for 4.0 h. Cells and supernatants were also collected. The release of TNF-alpha and IL-10 was analyzed via enzyme-linked immunosorbent assay (ELISA) and HSP70 via Western Blot. In this experiment, the effect of Quercetin on TNF-alpha, IL-10 and HSP70 expression in human PBMCs was assessed.


RESULTS
Gln led to an increase in HSP70 expression, and decreased TNF-alpha, IL-10 release at 4.0 h after LPS stimulation when 8 mmol/L glutamine pretreated for 0.5 h and 2.0 h, 15 mmol/L glutamine pretreated for 0.5 h (P < 0.05). The expression level of HSP70 was significantly decreased, however, the expression of TNF-alpha and IL-10 was enhanced in Quercetin group (P < 0.05).


CONCLUSIONS
The effect of glutamine attenuating cytokine release in PBMCs is related to the enhancement of HSP70 expression.
Wang
Li-ming
LM
Research Institute of General Surgery, Nanjing General Hospital of Nanjing Military Command, Nanjing 210002, China.
Pan
Li-ya
LY
Zhang
Feng
F
Wang
Xin-ying
XY
Li
Jie-shou
JS
D002478:Cells, Cultured; D016207:Cytokines / Q000378:metabolism*; D005973:Glutamine / Q000494:pharmacology*; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism; D006801:Humans; D016753:Interleukin-10 / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D016207:Cytokines; D018840:HSP70 Heat-Shock Proteins; D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha; D005973:Glutamine; D016753:Interleukin-10