Arabincoside B isolated from Caralluma arabica as a potential anti-pneumonitis in LPS mice model.

Acute lung injury (ALI) is a life-threatening condition usually associated with poor therapeutic outcomes and a high mortality rate. Since 2019, the situation has worsened due to the COVID-19 pandemic. ALI had approximately 40% of deaths before COVID-19, mainly due to the dysfunction of the blood-gas barrier that led to lung edema, failure of gas exchange, and dyspnea. Many strategies have been taken to mitigate the disease condition, such as diuretics, surfactants, antioxidants, glucocorticoids, heparin, and ventilators with concomitant sedatives. However, until now, there is no available effective therapy for ALI. Thus, we are presenting a new compound termed Arabincoside B (AR-B), recently isolated from Caralluma arabica, to be tested in such conditions. For that, the lipopolysaccharide (LPS) mice model was used to investigate the capability of the AR-B compound to control the ALI compared to standard dexamethasone. The results showed that AR-B had a significant effect on retrieving ALI. A further mechanistic study carried out in the serum, lung homogenate, histological, and immunohistochemistry sections revealed that the AR-B either in 50 mg/kg or 75 mg/kg dose inhibited pro-inflammatory cytokines such as IL-6, IL-13, NF-κB, TNFα, and NO and stimulated regulatory cytokines IL-10. Moreover, AR-B showed a considerable potential to protect the pulmonary tissue against oxidative stress by decreasing MDA and increasing catalase and Nrf2. Also, the AR-B exhibited an anti-apoptotic effect on the lung epithelium, confirmed by reducing COX and BAX expression and upregulating Bcl-2 expression. These results pave its clinical application for ALI.