Effects of SIRT1/Akt pathway on chronic inflammatory response and lung function in patients with asthma

Asthma is the most common chronic airway inflammatory disease. Sirtuin 1 (SIRT1) exerts a crucial effect on regulating chronic inflammatory responses. Therefore, this study aims to explore the effect of SIRT1 on the pathogenesis of asthma.

Serum level of SIRT1 in asthma patients and healthy controls was detected by Western blot. Correlation between SIRT1 level and pulmonary function in asthma patients was analyzed. Subsequently, asthma model in mouse was established. Primary airway epithelial cells were extracted from asthma mice and control mice to detect SIRT1 level. Furthermore, relative levels of Akt and interleukin 6 (IL-6) were detected in 16HBE cells. Regulatory effects of Akt on SIRT1 in 16HBE cells were determined as well.

SIRT1 was highly expressed in serum of asthma patients, which was negatively correlated with FEV1/FVC (r=-0.27, **p<0.01). Both mRNA and protein levels of SIRT1 were downregulated in primary airway epithelial cells extracted from asthma mice compared with those from controls. SIRT1 knockdown in 16HBE cells upregulated IL-6 expression, which was reversed by Akt inhibitors.

SIRT1 regulates IL-6 level via Akt pathway, thereafter affecting pulmonary function in asthma patients.