Besides lowering cholesterol, statins exert multiple effects, such as anti-inflammatory activity and improvement of endothelial cell function. We examined whether simvastatin (SS) protects against the development of elastase-induced pulmonary emphysema in mice by using mean linear intercepts of alveoli (Lm) as a morphometric parameter of emphysema. After injection of intratracheal elastase on day 0, C57BL/6 mice were treated daily with SS (SS+ group) or PBS (SS− group) for 2 wk. A 21% decrease in Lm on day 7 was observed in the SS+ group vs. the SS− group. Anti-inflammatory effects of SS were observed as a decrease in percentage of neutrophils up to day 3, and in hydroxyproline concentration on day 3, in bronchoalveolar lavage fluid (BALF). SS also increased the number of proliferating cell nuclear antigen (PCNA)-positive alveolar epithelial cells between days 3 and 14. To confirm the role of statins in promoting proliferation of alveolar cells, mice were treated with SS (SS+) vs. PBS (SS−) for 12 days, starting 3 wk after elastase administration. After SS treatment, Lm decreased by 52% and PCNA-positive alveolar epithelial cells increased compared with the SS− group. Concentrations of vascular endothelial growth factor in BALF and endothelial nitric oxide synthase protein expression in pulmonary vessels tended to be higher in the SS+ group vs. the SS− group in this protocol. In conclusion, SS inhibited the development of elastase-induced pulmonary emphysema in mice. This therapeutic effect was due not only to anti-inflammation but also to the promotion of alveolar epithelial cell regeneration, partly mediated by restoring endothelial cell functions.

The whole gene deletion CYP2A6*4, the defect of the main nicotine oxidase, contributes to limiting lifelong and daily cigarette consumption. However, the effects on smoking habits of CYP2A6*7 and *9, two major functional polymorphisms common in Asian populations, have not been reported.The present study examined the relationship between polymorphisms *4, *7 and *9 with the smoking habits of 200 Japanese smokers who visited the Keio University Hospital (Tokyo, Japan).The allele frequencies of *1 (wild type), *4, *7 and *9 were 52, 17, 11 and 20%, respectively. When the three polymorphisms were considered simultaneously, the percentages of homozygous wild type, heterozygote, and homozygous mutants and compound heterozygotes were 26.0, 52.5 and 21.5%, respectively. Homozygous mutants and compound heterozygotes (n543) smoked fewer cigarettes daily than heterozygotes (n5105) and homozygous wild-type individuals (n552).

Novel functional polymorphisms were identified in the cathepsin S gene, which has a possible association with pulmonary emphysema in the Japanese population.