Quantitative lung morphology in a regenerative lung model

Abstract

Einleitung: Several lung diseases are caused by the loss of alveolar septae or alveolar remodelling. But the ability of some mammals to regenerate the lungs provides an opportunity to study regenerative mechanisms. Understanding these mechanisms will provide us with a rationale for the therapeutic purpose. The aim of our study is to decipher lung regeneration at cellular and structural levels using a stereological approach in a murine calorie restriction model. Methoden: Calorie restriction murine model, stereological methods to study structural parameters such as alveolar number, alveolar volume, alveolar wall thickness, hyperplasia (cell number), hypertrophy, total lung volume. Molecular study using real time PCR, immunohistochemistry, semi quantitative PCR. Ergebnisse: We established a calorie restriction murine model with 50% reduction in food intake. We could show that with this food regime, mice lost approx. 30% body mass within 3 days which remained constant up to 10 days. We observed reduction in lung volume measured physically and with the Cavallieri method after 10 days of calorie restriction. We also observed the reduction in alveoli number during starvation. With refeeding, we observed restoration of body mass, lung volume and alveolar number comparable to control mice receiving normal food diet. The stereological measurements are ongoing. Diskussion: Calorie restriction and refeeding has impact on lung volume and has been reported to induce alveolar regression and regeneration, respectively. Our further studies will focus on the structural details, the cell types involved and their characterisation in the lung of starved and refed mice using stereological approaches.