Nitric oxide detection in cell culture exposed to LPS after Er:YAG laser irradiation

Author(s)

Rocha, R. A. S. S. ^[1] ; Silva, R. A. B. ^[1] ; Assed, S. ^[1] ; Medeiros, A. I. ^[2] ; Faccioli, L. H. ^[2] ; Pecora, J. D. ^[3] ; Nelson-Filho, P. ^[1]

Affiliation

^[1] Univ Sao Paulo, Dent Sch Ribeirao Preto, Dept Paediat Prevent & Community Dent, BR-14040904 Ribeirao Preto, SP - Brazil

^[2] Univ Sao Paulo, Dept Clin Toxicol & Bromatol Anal, Sch Pharmaceut Sci Ribeirao Preto, BR-14040904 Ribeirao Preto, SP - Brazil

^[3] Univ Sao Paulo, Dept Restorat Dent, Dent Sch Ribeirao Preto, BR-14040904 Ribeirao Preto, SP - Brazil

• Document type: Journal article
• Source: International Endodontic Journal; v. 42, n. 11, p. 992-996, NOV 2009.
• Web of Science Citations: 6

Abstract

P>Aim To evaluate in vitro the effect of calcium hydroxide {[}Ca(OH)(2)] and Er:YAG laser on bacterial endotoxin {[}also known as lipopolysaccharide (LPS)] as determined by nitric oxide (NO) detection in J774 murine macrophage cell line culture. Methodology Samples of LPS solution (50 mu gmL-1), Ca(OH)(2) suspension (25 mg mL-1) and LPS suspension with Ca(OH)(2) were prepared. The studied groups were: I - LPS (control); II - LPS + Ca(OH)(2); III - LPS + Er:YAG laser (15 Hz 140 mJ); IV - LPS + Er:YAG laser (15 Hz 200 mJ); V - LPS + Er:YAG laser (15 Hz 250 mJ), VI - Pyrogen-free water; VII - Ca(OH)(2). Murine macrophage J774 cells were plated and 10 mu L of the samples were added to each well. The supernatants were collected for NO detection by the Griess reaction. Data were analysed statistically by one-way anova and Tukey's test at 5% significance level. Results The mean and SE (in mu mol L-1) values of NO release were: I - 10.48 +/- 0.58, II - 6.41 +/- 0.90, III - 10.2 +/- 0.60, IV - 8.35 +/- 0.40, V - 10.40 +/- 0.53, VI - 3.75 +/- 0.70, VII - 6.44 +/- 0.60; and the values for the same experiment repeated after 1 week were: I - 21.20 +/- 1.50, II - 9.10 +/- 0.60, III - 19.50 +/- 1.00, IV - 18.50 +/- 0.60, V - 21.30 +/- 0.90, VI - 2.00 +/- 0.20, VII - 6.80 +/- 1.70. There was no significant difference (P > 0.05) between the control and the laser-treated groups (III, IV and V), or comparing groups II, VI and VII to each other (P > 0.05). Group I had significantly higher NO release than group II (P < 0.05). Groups II and VI had similar NO release (P > 0.05). Conclusions Calcium hydroxide inactivated the bacterial endotoxin (LPS) whereas none of the Er:YAG laser parameter settings had the same effectiveness. (AU)

• FAPESP's process: 02/12856-2 - Modulation of innate and acquired immune responses by leukotrienes and prostaglandins
• Grantee: Lúcia Helena Faccioli
• Support Opportunities: Research Projects - Thematic Grants