Inhaled ozone induces distinct alterations in pulmonary function in models of acute and episodic exposure in female mice

Area of Science:

• Environmental toxicology
• Pulmonary medicine
• Respiratory system research

Background:

• Ozone is a harmful urban air pollutant.
• Ozone inhalation causes lung injury and functional changes.
• Acute and episodic ozone exposure models reveal distinct lung responses.

Purpose of the Study:

• To investigate the functional consequences of acute and episodic ozone inhalation.
• To correlate structural lung changes with pulmonary function alterations.
• To analyze changes in lung surfactant composition following ozone exposure.

Main Methods:

• Established models of acute (0.8 ppm, 3 h) and episodic (1.5 ppm, 2 h, 2x/wk, 6 wk) ozone inhalation.
• Small animal ventilator used for lung function assessment (impedance, resistance, elastance).
• Analysis of pressure-volume (PV)-loops and bronchoalveolar lavage fluid (surfactant protein D, phospholipids).

Main Results:

• Episodic ozone reduced lung elastance and increased airway hyperresponsiveness (methacholine challenge).
• Acute ozone decreased lung volume (PV-loops), while episodic ozone increased it.
• Acute exposure increased lung phospholipids and surfactant protein D; episodic exposure increased only total surfactant protein D.

Conclusions:

• Acute and episodic ozone exposure induce different pulmonary functional and compositional changes.
• Acute ozone effects linked to surfactant alterations and inflammation; episodic ozone effects to structural remodeling and hyperresponsiveness.
• Distinct exposure patterns of ozone lead to divergent lung injury mechanisms and functional outcomes.