Withania somnifera deploys immunomodulation and exerts anticancer effects on lung adenocarcinoma cells

Abstract

Immunomodulation using phytochemicals is the alternate therapeutic modality to treat cancer. Withania somnifera (L.) Dunal is known to possess several pharmacological activities such as anti-inflammatory, anti-arthritic, neuroprotective and antitumor activity . In this study, we have evaluated the immunomodulatory and anticancer effects of W. somnifera (L.) Dunal ethanolic extract on lung adenocarcinoma cells. Anti- inflammatory effect was assessed using albumin denaturation method. Cell viability of murine macrophage cells was evaluated using MTT assay and nitric oxide scavenging capacity was assessed using Griess method. Compatibility of the extract on RAW 267.4 and THP 1 cells was assessed using morphological assessment, AO-EB and Hoechst staining methods. Further, RAW 267.4 (macrophage) and THP 1 (monocyte) cells were treated with the extract to assess the arginase, phagocytic and pinocytic activity. W. somnifera (L.) Dunal extract was administered to lung adenocarcinoma cells and evaluated for the induction of ROS to indicate the apoptotic effects. Further, immunofluorescence and immunoblotting was performed using the cell lysates to study the effect of extract on the expression of CTLA 4, HIF-1 α , TNF- α , and PECAM-1. In this study we found that, W. somnifera (L.) Dunal extract showed a dose dependent inhibition of protein denaturation and the extract did not show any cytotoxicity on RAW 267.4 cells. Griess assay performed with the culture supernatants revealed that the extract exhibited a dose dependent inhibition of NO production. RAW 267.4 and THP 1 cells showed a significant inhibition of arginase activity with ⁎⁎⁎ p <0.0005. At higher concentration of treatment, both the immune cells displayed a significant increase in the phagocytic and pinocytic effect. W. somnifera (L.) Dunal treatment increased the ROS production in lung adenocarcinoma cells and downregulated the expressions of CTLA-4, HIF-1 α , TNF- α , and PECAM-1. This study confirmed that W. somnifera (L.) Dunal ethanol extract possesses immunomodulatory effect, to enhance the cell death in lung cancer cells via ROS generation. • Ashwagandha has the ability to enhance nitric oxide scavenging activity, along with decreased activity of arginase, which is responsible for the cancer cell invasion and metastasis. • Ashwagandha regulates the phagocytic and pinocytic property in macrophages and monocytes, indicating the cellular defense against abnormal cells. • ROS generation is responsible for the apoptosis of the cells, upon treatment of ashwagandha A549 lung adenocarcinoma cells showed apoptosis by increasing the expression of ROS. • Decreased expression of HIF-1 α & TNF- α promotes cancer cell death.