J Korean Acad Periodontol.  2008 Sep;38(3):511-520.

The effect of high concentration of glucose on the production of proinflammatory cytokines and nitric oxide induced by lipopolysaccharides from periodontopathic bacteria

• Kim SJ

Abstract

PURPOSE
Diabetes mellitus is a clinically and genetically heterogeneous group of metabolic disorders manifested by abnormally high levels of glucose in the blood. Mounting evidence demonstrates that diabetes is a risk factor for gingivitis and periodontitis. The circulating mononuclear phagocytes in diabetic patients with hyperglycemia are chronically exposed to high level of serum glucose. Thus, this study attempted to determine the effect of pre-exposure of monocytes and macrophages to high concentration of glucose on lipopolysaccharide (LPS)-induced production of pro-inflammatory mediators. MATERIAL AND METHODS: For this purpose, cells were cultured in medium containing normal (5 mM) or high glucose (25 mM) for 4-5 weeks before treatment for 24 h with LPS. LPS was highly purified from Porphyromonas gingivalis or Prevotella intermedia by phenol extraction. RESULT: Results showed that prolonged pre-exposure of cells to high glucose markedly increased LPS-stimulated NO secretion when compared to normal glucose. In addition to NO, high glucose also augmented LPS-stimulated IL-6, IL-8, and TNF-alpha secretion after cells were exposed to high glucose for 4 weeks.
CONCLUSION
The present study demonstrates that pre-exposure of mononuclear phagocytes with high glucose augments LPS-stimulated production of pro-inflammatory mediators. These findings may explain why periodontal tissue destruction in diabetic patients is more severe than that in non-diabetic individuals.

Keyword

diabetes mellitus; hyperglycemia; pro-inflammatory mediators; mononuclear phagocytes; lipopolysaccharide

MeSH Terms

Bacteria
Cytokines
Diabetes Mellitus
Gingivitis
Glucose
Humans
Hyperglycemia
Interleukin-6
Interleukin-8
Lipopolysaccharides
Macrophages
Monocytes
Nitric Oxide
Periodontitis
Phagocytes
Phenol
Porphyromonas gingivalis
Prevotella intermedia
Risk Factors
Tumor Necrosis Factor-alpha
Cytokines
Glucose
Interleukin-6
Interleukin-8
Lipopolysaccharides
Nitric Oxide
Phenol
Tumor Necrosis Factor-alpha