Associations of Inflammation, Oxidative Stress and Prognosis with IL-37 Expression in Sepsis Rats with Lung Injury

Abstract

This study aimed to investigate the role of interleukin-37 (IL-37) expression in lung tissues of sepsis-induced acute lung injury (ALI) rats and its impact on ALI, along with the underlying mechanisms. Sprague-Dawley (SD) rats were categorized into three groups: Control, sepsis-induced ALI (via cecal ligation and puncture, CLP), and sepsis-induced ALI with antibiotics (CLP+An). ALI models were established, and lung tissue injuries were assessed through hematoxylineosin staining. mRNA levels of IL-1α, IL-1β, IL-37, and tumor necrosis factor-α (TNF-α) were measured via RT-PCR, while IL-37 protein levels in lung tissues were determined using Western blotting. Additionally, bronchoalveolar lavage fluid (BALF) and blood samples were collected to assess inflammatory factors through ELISA. In the CLP group, there was an increase in pro-inflammatory factors (IL-1α, IL-1β, and TNF-α) in lung tissues and serum. However, in the CLP+An group, these factors decreased, IL-37 expression increased, and oxidative stress levels decreased. IL-37 demonstrated an inhibitory effect on the release of pro-inflammatory factors (IL-1α, IL-1β, and TNF-α) in sepsis rats, leading to a reduction in lung tissue inflammation. Furthermore, IL-37 exhibited a protective role by reducing oxidative stress in sepsis-induced lung tissues. These findings highlight IL-37 as a potential therapeutic target for mitigating ALI in sepsis.