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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

Inhibitory effect of GGA on lipid A-mediated NO production in RAW 264 cells. Cells were incubated in the presence or absence of Lipid A (LA) (100 ng/ml) for 24 h at 37°C under a 5% CO2 and 95% air atmosphere. GGA (80 µM) was added 2 h before the addition of LA. NO level was measured as described in Materials and Methods. Data points represent the means ± SE (n = 3). ap<0.01 vs LA alone-treated cells.
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Figure 8: Inhibitory effect of GGA on lipid A-mediated NO production in RAW 264 cells. Cells were incubated in the presence or absence of Lipid A (LA) (100 ng/ml) for 24 h at 37°C under a 5% CO2 and 95% air atmosphere. GGA (80 µM) was added 2 h before the addition of LA. NO level was measured as described in Materials and Methods. Data points represent the means ± SE (n = 3). ap<0.01 vs LA alone-treated cells.

Mentions: To determine whether the inhibitory effect of GGA on LPS-mediated macrophage activation is due to its action on lipid A, we examined the effect of GGA on NO production in lipid A-treated RAW 264 cells (Fig. 8). NO contents in the medium increased dose-dependently 24 h after treatment of RAW 264 cells with lipid A at doses of 0.01–100 ng/ml (data not shown). Pretreatment of the cells with 80 µM GGA significantly decreased NO concentration by 35% at 24 h after lipid A (100 ng/ml) challenge in comparison with lipid A alone, completely consistent with inhibitory effect of GGA on LPS-mediated NO production (Fig. 8, compare with Fig. 3A).


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)

Inhibitory effect of GGA on lipid A-mediated NO production in RAW 264 cells. Cells were incubated in the presence or absence of Lipid A (LA) (100 ng/ml) for 24 h at 37°C under a 5% CO2 and 95% air atmosphere. GGA (80 µM) was added 2 h before the addition of LA. NO level was measured as described in Materials and Methods. Data points represent the means ± SE (n = 3). ap<0.01 vs LA alone-treated cells.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

Figure 8: Inhibitory effect of GGA on lipid A-mediated NO production in RAW 264 cells. Cells were incubated in the presence or absence of Lipid A (LA) (100 ng/ml) for 24 h at 37°C under a 5% CO2 and 95% air atmosphere. GGA (80 µM) was added 2 h before the addition of LA. NO level was measured as described in Materials and Methods. Data points represent the means ± SE (n = 3). ap<0.01 vs LA alone-treated cells.
Mentions: To determine whether the inhibitory effect of GGA on LPS-mediated macrophage activation is due to its action on lipid A, we examined the effect of GGA on NO production in lipid A-treated RAW 264 cells (Fig. 8). NO contents in the medium increased dose-dependently 24 h after treatment of RAW 264 cells with lipid A at doses of 0.01–100 ng/ml (data not shown). Pretreatment of the cells with 80 µM GGA significantly decreased NO concentration by 35% at 24 h after lipid A (100 ng/ml) challenge in comparison with lipid A alone, completely consistent with inhibitory effect of GGA on LPS-mediated NO production (Fig. 8, compare with Fig. 3A).

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