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Geranylgeranylacetone ameliorates inflammatory response to lipopolysaccharide (LPS) in murine macrophages: inhibition of LPS binding to the cell surface.

Mochida S, Matsura T, Yamashita A, Horie S, Ohata S, Kusumoto C, Nishida T, Minami Y, Inagaki Y, Ishibe Y, Nakada J, Ohta Y, Yamada K - J Clin Biochem Nutr (2007)

Bottom Line: GGA (80 microM) treatment 2 h before LPS addition significantly suppressed TNF-alpha and NO productions at 12 h and 24 h after LPS, respectively, indicating that GGA inhibits activation of macrophages.When it was examined whether GGA interacts with LPS and/or affects expression of Toll-like receptor 4 (TLR4) and CD14 on the cell surface, GGA inhibited the binding of LPS to the cell surface, while GGA did not affect TLR4 and CD14 expressions.These results indicate that GGA suppresses the binding of LPS to the cell surface of macrophages, resulting in inhibiting signal transduction downstream of TLR4.

View Article: PubMed Central - PubMed

Affiliation: Division of Medical Biochemistry, Department of Pathophysiological and Therapeutic Science, Tottori University Faculty of Medicine, 86 Nishi-cho, Yonago 683-8503, Japan.

ABSTRACT
We investigated whether pretreatment with geranylgeranylacetone (GGA), a potent heat shock protein (HSP) inducer, could inhibit proinflammatory cytokine liberation and nitric oxide (NO) production in lipopolysaccharide (LPS)-treated murine macrophages. The levels of NO and tumor necrosis factor-alpha (TNF-alpha) released from murine macrophage RAW 264 cells were increased dose- and time-dependently following treatment with LPS (1 microg/ml). GGA (80 microM) treatment 2 h before LPS addition significantly suppressed TNF-alpha and NO productions at 12 h and 24 h after LPS, respectively, indicating that GGA inhibits activation of macrophages. However, replacement by fresh culture medium before LPS treatment abolished the inhibitory effect of GGA on NO production in LPS-treated cells. Furthermore, GGA inhibited both HSP70 and inducible NO synthase expressions induced by LPS treatment despite an HSP inducer. When it was examined whether GGA interacts with LPS and/or affects expression of Toll-like receptor 4 (TLR4) and CD14 on the cell surface, GGA inhibited the binding of LPS to the cell surface, while GGA did not affect TLR4 and CD14 expressions. These results indicate that GGA suppresses the binding of LPS to the cell surface of macrophages, resulting in inhibiting signal transduction downstream of TLR4.

No MeSH data available.


Related in: MedlinePlus

Time-dependent production of NO (A) and TNF-α (B) in RAW 264 cells by LPS treatment. Cells were incubated with LPS (1 µg/ml) for 4, 8, 12 or 24 h at 37°C under a 5% CO2 and 95% air atmosphere. The levels of NO and TNF-α were measured as described in Materials and Methods. Data points represent the means ± SE (n = 3). ap<0.01 vs 0 h, bp<0.01 vs 12 h.
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Figure 2: Time-dependent production of NO (A) and TNF-α (B) in RAW 264 cells by LPS treatment. Cells were incubated with LPS (1 µg/ml) for 4, 8, 12 or 24 h at 37°C under a 5% CO2 and 95% air atmosphere. The levels of NO and TNF-α were measured as described in Materials and Methods. Data points represent the means ± SE (n = 3). ap<0.01 vs 0 h, bp<0.01 vs 12 h.

Mentions: To determine the concentration of LPS required for inducing production of NO and TNF-α in RAW 264 cells, we treated the cells with LPS at concentrations ranging from 10 to 1000 ng/ml for 24 and 12 h, respectively (Fig. 1). LPS induced NO production in a dose-dependent manner (Fig. 1A). TNF-α concentration in medium also increased in a dose-dependent manner (Fig. 1B). We next examined the time course of changes in release of NO and TNF-α from RAW 264 cells following treatment with LPS (1 µg/ml) (Fig. 2). NO concentration in medium increased with time up to 24 h (Fig. 2A). TNF-α level in medium also increased time-dependently, reached a maximum at 12 h and decreased at 24 h after LPS addition (Fig. 2B). These results were consistent with those in the previous study that LPS treatment of murine macrophages resulted in the early expression of TNF-α and the subsequent synthesis of iNOS [23].


Geranylgeranylacetone ameliorates inflammatory response to lipopolysaccharide (LPS) in murine macrophages: inhibition of LPS binding to the cell surface.

Mochida S, Matsura T, Yamashita A, Horie S, Ohata S, Kusumoto C, Nishida T, Minami Y, Inagaki Y, Ishibe Y, Nakada J, Ohta Y, Yamada K - J Clin Biochem Nutr (2007)

Time-dependent production of NO (A) and TNF-α (B) in RAW 264 cells by LPS treatment. Cells were incubated with LPS (1 µg/ml) for 4, 8, 12 or 24 h at 37°C under a 5% CO2 and 95% air atmosphere. The levels of NO and TNF-α were measured as described in Materials and Methods. Data points represent the means ± SE (n = 3). ap<0.01 vs 0 h, bp<0.01 vs 12 h.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2170953&req=5

Figure 2: Time-dependent production of NO (A) and TNF-α (B) in RAW 264 cells by LPS treatment. Cells were incubated with LPS (1 µg/ml) for 4, 8, 12 or 24 h at 37°C under a 5% CO2 and 95% air atmosphere. The levels of NO and TNF-α were measured as described in Materials and Methods. Data points represent the means ± SE (n = 3). ap<0.01 vs 0 h, bp<0.01 vs 12 h.
Mentions: To determine the concentration of LPS required for inducing production of NO and TNF-α in RAW 264 cells, we treated the cells with LPS at concentrations ranging from 10 to 1000 ng/ml for 24 and 12 h, respectively (Fig. 1). LPS induced NO production in a dose-dependent manner (Fig. 1A). TNF-α concentration in medium also increased in a dose-dependent manner (Fig. 1B). We next examined the time course of changes in release of NO and TNF-α from RAW 264 cells following treatment with LPS (1 µg/ml) (Fig. 2). NO concentration in medium increased with time up to 24 h (Fig. 2A). TNF-α level in medium also increased time-dependently, reached a maximum at 12 h and decreased at 24 h after LPS addition (Fig. 2B). These results were consistent with those in the previous study that LPS treatment of murine macrophages resulted in the early expression of TNF-α and the subsequent synthesis of iNOS [23].

Bottom Line: GGA (80 microM) treatment 2 h before LPS addition significantly suppressed TNF-alpha and NO productions at 12 h and 24 h after LPS, respectively, indicating that GGA inhibits activation of macrophages.When it was examined whether GGA interacts with LPS and/or affects expression of Toll-like receptor 4 (TLR4) and CD14 on the cell surface, GGA inhibited the binding of LPS to the cell surface, while GGA did not affect TLR4 and CD14 expressions.These results indicate that GGA suppresses the binding of LPS to the cell surface of macrophages, resulting in inhibiting signal transduction downstream of TLR4.

View Article: PubMed Central - PubMed

Affiliation: Division of Medical Biochemistry, Department of Pathophysiological and Therapeutic Science, Tottori University Faculty of Medicine, 86 Nishi-cho, Yonago 683-8503, Japan.

ABSTRACT
We investigated whether pretreatment with geranylgeranylacetone (GGA), a potent heat shock protein (HSP) inducer, could inhibit proinflammatory cytokine liberation and nitric oxide (NO) production in lipopolysaccharide (LPS)-treated murine macrophages. The levels of NO and tumor necrosis factor-alpha (TNF-alpha) released from murine macrophage RAW 264 cells were increased dose- and time-dependently following treatment with LPS (1 microg/ml). GGA (80 microM) treatment 2 h before LPS addition significantly suppressed TNF-alpha and NO productions at 12 h and 24 h after LPS, respectively, indicating that GGA inhibits activation of macrophages. However, replacement by fresh culture medium before LPS treatment abolished the inhibitory effect of GGA on NO production in LPS-treated cells. Furthermore, GGA inhibited both HSP70 and inducible NO synthase expressions induced by LPS treatment despite an HSP inducer. When it was examined whether GGA interacts with LPS and/or affects expression of Toll-like receptor 4 (TLR4) and CD14 on the cell surface, GGA inhibited the binding of LPS to the cell surface, while GGA did not affect TLR4 and CD14 expressions. These results indicate that GGA suppresses the binding of LPS to the cell surface of macrophages, resulting in inhibiting signal transduction downstream of TLR4.

No MeSH data available.


Related in: MedlinePlus