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Using the one-lung method to link p38 to pro-inflammatory gene expression during overventilation in C57BL/6 and BALB/c mice.

Siegl S, Uhlig S - PLoS ONE (2012)

Bottom Line: This hypothesis was confirmed in experiments with the p38-kinase inhibitor SB203580.The one-lung method is useful for mechanistic studies in the lungs.Finally, the one-lung method allowed us to link p38 to gene expression during VILI.

View Article: PubMed Central - PubMed

Affiliation: Institute of Pharmacology and Toxicology, Medical Faculty, RWTH Aachen University, Aachen, Germany.

ABSTRACT

Introduction: The mechanisms of ventilator-induced lung injury (VILI), including the role of MAP kinases, are frequently studied in different mouse strains. A useful model for such studies is the isolated perfused mouse lung. As a further development we present the one-lung method that permits to continue perfusion and ventilation of the right lung after removal of the left lung. This method was used to compare the effect of high pressure ventilation (HPV) on pro-inflammatory signaling events in two widely used mouse strains (C57BL/6, BALB/c) and to further define the role of p38 in VILI.

Methods: Lungs were perfused and ventilated for 30 min under control conditions before they were randomized to low (8 cm H(2)O) or high (25 cm H(2)O) pressure ventilation (HPV) for 210 min, with the left lung being removed after 180 min. In the left lung we measured the phosphorylation of p38, JNK, ERK and Akt kinase, and in the right lung gene expression and protein concentrations of Il1b, Il6, Tnf, Cxcl1, Cxcl2, and Areg.

Results: Lung mechanics and kinase activation were similar in both mouse strains. HPV increased all genes (except Tnf in BALB/c) and all mediators in both strains. The gene expression of mRNA for Il1b, Il6, Cxcl1 and Cxcl2 was higher in BALB/c mice. Backward regression of the kinase data at t = 180 min with the gene and protein expression data at t = 240 min suggested that p38 controls HPV-induced gene expression, but not protein production. This hypothesis was confirmed in experiments with the p38-kinase inhibitor SB203580.

Conclusions: The one-lung method is useful for mechanistic studies in the lungs. While C57BL/6 show diminished pro-inflammatory responses during HPV, lung mechanics and mechanotransduction processes appear to be similar in both mouse strains. Finally, the one-lung method allowed us to link p38 to gene expression during VILI.

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Tidal volume of C57BL/6 and BALB/c mice during low and high pressure ventilation.Data are represented as mean + SEM with n = 6 per study group. The differences in tidal volume and compliance between LPV and HPV were significant (p<0.01; two way ANOVA). BALB/c and C57BL/6 mice did not differ in tidal volume. C57BL/6 =  triangles; BALB/c  =  circles; LPV  =  open symbols; HPV  =  closed symbols.
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pone-0041464-g002: Tidal volume of C57BL/6 and BALB/c mice during low and high pressure ventilation.Data are represented as mean + SEM with n = 6 per study group. The differences in tidal volume and compliance between LPV and HPV were significant (p<0.01; two way ANOVA). BALB/c and C57BL/6 mice did not differ in tidal volume. C57BL/6 =  triangles; BALB/c  =  circles; LPV  =  open symbols; HPV  =  closed symbols.

Mentions: Tidal volume remained stable over the entire ventilation period in the LPV group with no differences between the two strains (Fig. 2A). HPV increased the tidal volume, again with no difference between the two strains. As described before [27], [30], because we used pressure-control ventilation, tidal volumes decreased during overventilation. At the time of removal of the left lung, the tidal volumes had returned nearly back to baseline. After left lung removal, all of the remaining right lungs received similar tidal volumes of about 80 µL. Tidal volume and compliance did not differ in BALB/c mice when perfused with the p38 MAP kinase inhibitor SB203580 or the solvent DMSO (data not shown).


Using the one-lung method to link p38 to pro-inflammatory gene expression during overventilation in C57BL/6 and BALB/c mice.

Siegl S, Uhlig S - PLoS ONE (2012)

Tidal volume of C57BL/6 and BALB/c mice during low and high pressure ventilation.Data are represented as mean + SEM with n = 6 per study group. The differences in tidal volume and compliance between LPV and HPV were significant (p<0.01; two way ANOVA). BALB/c and C57BL/6 mice did not differ in tidal volume. C57BL/6 =  triangles; BALB/c  =  circles; LPV  =  open symbols; HPV  =  closed symbols.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3404097&req=5

pone-0041464-g002: Tidal volume of C57BL/6 and BALB/c mice during low and high pressure ventilation.Data are represented as mean + SEM with n = 6 per study group. The differences in tidal volume and compliance between LPV and HPV were significant (p<0.01; two way ANOVA). BALB/c and C57BL/6 mice did not differ in tidal volume. C57BL/6 =  triangles; BALB/c  =  circles; LPV  =  open symbols; HPV  =  closed symbols.
Mentions: Tidal volume remained stable over the entire ventilation period in the LPV group with no differences between the two strains (Fig. 2A). HPV increased the tidal volume, again with no difference between the two strains. As described before [27], [30], because we used pressure-control ventilation, tidal volumes decreased during overventilation. At the time of removal of the left lung, the tidal volumes had returned nearly back to baseline. After left lung removal, all of the remaining right lungs received similar tidal volumes of about 80 µL. Tidal volume and compliance did not differ in BALB/c mice when perfused with the p38 MAP kinase inhibitor SB203580 or the solvent DMSO (data not shown).

Bottom Line: This hypothesis was confirmed in experiments with the p38-kinase inhibitor SB203580.The one-lung method is useful for mechanistic studies in the lungs.Finally, the one-lung method allowed us to link p38 to gene expression during VILI.

View Article: PubMed Central - PubMed

Affiliation: Institute of Pharmacology and Toxicology, Medical Faculty, RWTH Aachen University, Aachen, Germany.

ABSTRACT

Introduction: The mechanisms of ventilator-induced lung injury (VILI), including the role of MAP kinases, are frequently studied in different mouse strains. A useful model for such studies is the isolated perfused mouse lung. As a further development we present the one-lung method that permits to continue perfusion and ventilation of the right lung after removal of the left lung. This method was used to compare the effect of high pressure ventilation (HPV) on pro-inflammatory signaling events in two widely used mouse strains (C57BL/6, BALB/c) and to further define the role of p38 in VILI.

Methods: Lungs were perfused and ventilated for 30 min under control conditions before they were randomized to low (8 cm H(2)O) or high (25 cm H(2)O) pressure ventilation (HPV) for 210 min, with the left lung being removed after 180 min. In the left lung we measured the phosphorylation of p38, JNK, ERK and Akt kinase, and in the right lung gene expression and protein concentrations of Il1b, Il6, Tnf, Cxcl1, Cxcl2, and Areg.

Results: Lung mechanics and kinase activation were similar in both mouse strains. HPV increased all genes (except Tnf in BALB/c) and all mediators in both strains. The gene expression of mRNA for Il1b, Il6, Cxcl1 and Cxcl2 was higher in BALB/c mice. Backward regression of the kinase data at t = 180 min with the gene and protein expression data at t = 240 min suggested that p38 controls HPV-induced gene expression, but not protein production. This hypothesis was confirmed in experiments with the p38-kinase inhibitor SB203580.

Conclusions: The one-lung method is useful for mechanistic studies in the lungs. While C57BL/6 show diminished pro-inflammatory responses during HPV, lung mechanics and mechanotransduction processes appear to be similar in both mouse strains. Finally, the one-lung method allowed us to link p38 to gene expression during VILI.

Show MeSH
Related in: MedlinePlus