ORMDL3 Promotes Angiogenesis in Chronic Asthma Through the ERK1/2/VEGF/MMP-9 Pathway

Orai1/STIMs modulators in pulmonary vascular diseases

Calcium (Ca2+) is a secondary messenger that regulates various cellular processes. However, Ca2+ mishandling could lead to pathological conditions. Orai1 is a Ca2+channel contributing to the store-operated calcium entry (SOCE) and plays a critical role in Ca2+ homeostasis in several cell types. Dysregulation of Orai1 contributed to severe combined immune deficiency syndrome, some cancers, pulmonary arterial hypertension (PAH), and other cardiorespiratory diseases. During its activation process, Orai1 is mainly regulated by stromal interacting molecule (STIM) proteins, especially STIM1; however, many other regulatory partners have also been recently described. Increasing knowledge about these regulatory partners provides a better view of the downstream signalling pathways of SOCE and offers an excellent opportunity to decipher Orai1 dysregulation in these diseases. These proteins participate in other cellular functions, making them attractive therapeutic targets. This review mainly focuses on Orai1 regulatory partners in the physiological and pathological conditions of the pulmonary circulation and inflammation.

ORMDL3‑mediated bronchial epithelial pyroptosis leads to lung inflammation in obese mice with asthma

Asthma associated with obesity is a chronic disease that poses a threat to health in children and results in severe wheezing, earlier airway remodeling and increased insensitivity to hormone therapy compared with those who only have asthma. Despite its clinical importance, knowledge on the underlying mechanisms of this disease is limited. The present study aimed to elucidate the pathogenesis of asthma associated with obesity using a murine model. A total of 30 female BALB/c mice were divided into three groups: Normal, mice with asthma and obese mice with asthma. Obese mice with asthma were fed a high‑fat diet to induce obesity. Mice with asthma were sensitized and challenged with ovalbumin (OVA). Obese mice were subjected to OVA sensitization and challenge to develop asthma associated with obesity. Airway remodeling was observed in obese mice with asthma through HE and Masson staining. Proteomic and bioinformatics analyses were conducted on lung tissue from obese mice with asthma and normal mice. A total of 200 proteins were differentially expressed in obese mice with asthma compared with normal mice; of these, 53 and 47% were up‑ and downregulated, respectively. Pathway analysis revealed that asthma associated with obesity primarily affected the 'lysosome', 'phagosome', and 'sphingolipid metabolism' pathways. Gene Set Enrichment Analysis demonstrated the presence of pyroptosis in obese asthmatic mice, along with significant increases in pyroptosis‑-associated factors such as GSDMD and Caspase. High protein expression of orosomucoid‑like 3 (ORMDL3), NOD‑like receptor thermal protein domain associated protein 3 (NLRP3) and Gasdermin‑D (GSDMD) was observed in obese mice with asthma. In vitro experiments using HBE cells infected with ORMDL3‑overexpressing lentivirus demonstrated that the overexpression of ORMDL3 led to increased expression of NLRP3, GSDMD and cathepsin D (CTSD). These findings suggested that ORMDL3 may regulate pyroptosis and subsequent airway remodeling in asthma associated with obesity via the CTSD/NLRP3/GSDMD pathway.

Improvements of lung volumes and respiratory symptoms after weight loss through laparoscopic sleeve gastrectomy

PURPOSE

This study evaluated the improvement of respiratory function and airway volumes using spirometry and computed tomography (CT) in severely obese Japanese patients undergoing laparoscopic sleeve gastrectomy (LSG). We also evaluated the quality of life (QOL) of enrolled patients using questionnaires.

METHODS

A total of 71 patients who underwent LSG at Iwate Medical University Hospital between October 2013 and September 2020 were enrolled. The changes and relationships between respiratory parameters including CT volumetry and weight-loss effects were evaluated. Improvements to QOL and bronchial asthma (BA) were also assessed before LSG and 1 year after LSG.

RESULTS

The mean excess weight loss percentage (%EWL) and total weight loss percentage (%TWL) were measured at 55.1% and 26.1%, respectively. The attack frequency of BA significantly decreased (6.1/month vs. 1.5/month; P < 0.001), and the disease severity decreased according to severity classification (P = 0.032). Almost spirometric parameters, lung volume (LV) (4905.0 mL vs. 5490.3 mL; P < 0.001), and airway volume (AV) (108.6 mL vs. 119.3 mL; P = 0.022) significantly improved. The change of functional residual capacity (FRC) was correlated with both %EWL (ρ = 0.69, P < 0.001) and %TWL (ρ = 0.62, P < 0.001). The increase of LV (ρ = 0.79, P < 0.001) and AV (ρ = 0.69, P < 0.001) were correlated with the increase of FRC. Scores of QOL questionnaires dramatically became better owing to improvements in dyspnea.

CONCLUSION

Weight loss effects and the reduction of body fat mass correlated significantly with increase in LV and AV. Improvements of respiratory functions after LSG contributes to QOL and BA symptoms.