Acid sphingomyelinase (ASM) is one enzyme responsible for the production of ceramide via the hydrolysis of sphingomyelin.Recent findings have revealed the important role of ASM in the initiation of ceramide-induced cell apoptosis,as well as in the pathophysiology of many common diseases (e.g.cardiovascular diseases,diabetes,pulmonary diseases,and neurological diseases).Other studies have also shown that ASM activation may occur through the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS),as well as by inflammatory mechanisms that may be induced by environmental and occupational stresses.ASM activation,in turn,may create excess or abnormally distributed ceramides,which could lead to tissue and organ injuries,including to the pulmonary,liver,kidney,and nervous systems.This review will discuss the basic biology of ASM and focus on the role and regulation of ASM in environmental stress responses.We propose that ASM activation is an important factor in environmental health,and that ASM-based therapeutics may have a key role in preventing environmental-induced tissue injury.

Pulmonary fibrosis is a group of chronic lung diseases caused by various factors and characterized by chronic inflammations,lung tissue structure damage,increase of pulmonary interstitial collagen and massive deposition of extracellular matrix (ECM). Because of its complicated etiology, there is no effective treatment currently. Recent studies showed that the activation of sphingolipids signaling and pulmonary fibrosis were closely related. This paper describes the composition and function of sphingolipids signaling pathway and its effect on fibrosis in order to provide new ideas about further study of the pathogenesis of pulmonary fibrosis and methods of prevention.

Pulmonary fibrosis is a group of chronic lung diseases induced by various causes. Because of its complex etiology and pathogenesis,most of the pulmonary fibrosis diseases have no effective treatment currently and the quality of life and prognosis of patients are poor. Recent studies on biomarkers of susceptibility and effect associated with pulmonary fibrosis have made great progress, which is of great significance for screening and early diagnosis of the disease,and even for the evaluation of therapeutic efficacy and prognosis. This paper reviews some potential biomarkers of pulmonary fibrosis diseases,including the mucin 5B promoter variant and matrix metalloprotease-7 associated with idiopathic pulmonary fibrosis,heme oxygenase-1 and serum Se related to silicosis,Krebs von den Lungen-6,surfactant proteins-D and sphingolipids signaling associated with various pulmonary fibrosis, in order to provide new ideas for further research on the prevention and treatment of pulmonary fibrosis diseases.