Baicalin protected mice against radiation-induced lethality: A mechanistic study employing in silico and wet lab techniques

Baicalin is a main active ingredient of the dried root of Scutellaria and has been extensively employed in Traditional Chinese Medicine for the treatment of asthma, fever, and psoriasis. Based on the reports of antioxidant, anti-inflammatory, anti-infection, and anti-tumor activities of baicalin, we have explored its radioprotective efficacy using in vitro and in vivo experimental model systems. In the present study, we have investigated the radioprotective, immunomodulatory, and anti-inflammatory properties of baicalin using wet lab and in silico approaches. It was observed that pre-treatment of murine splenic lymphocytes with baicalin protected cells against radiation-induced cell death possibly by decreasing the cellular reactive oxygen species levels. Prophylactic oral administration of baicalin offered significant increase in endogenous spleen colony counts and an enhancement in the survival of mice. We have also observed that baicalin suppressed mitogen-induced splenic lymphocyte proliferation and IL-2 production. It also inhibited the production of nitric oxide in RAW 264.7 cells in response to elicitation of lipopolysaccharide. Further, in silico study was performed to evaluate the possible mechanism of radioprotection and immunomodulation by selecting different pro-inflammatory mediators such as COX2, Lck, NIK, and IKK-β which have a significant role in radioprotection, lymphocyte activation, and inflammation. Our molecular docking and molecular dynamics study show that baicalin has a significant predicted binding affinity with COX2, Lck, NIK, and IKK-β. These in silico results can explain the experimentally observed radioprotective, immunosuppressive, and anti-inflammatory properties of baicalin. Thus, radioprotection offered by baicalin may be because of its antioxidant, anti-inflammatory, and immunomodulatory properties.