Combination of Chemopreventive Agents (All- Trans Retinoic Acid and Tamoxifen) as Potential Treatment for the Lung Complication of COVID-19

Summary

Combination of Chemopreventive agents (All- Trans Retinoic Acid and Tamoxifen) as potential treatment for the Lung Complication of COVID-19 Abstract Angiotensin-converting enzyme (ACE2) protein found on the cell membranes is the target of SARS-CoV-2 for entering into the host cells. Viral spike protein-binding with ACE2 down-regulates it. As ACE2 is known to protect the lung from injuries, SARS-CoV-2-induced ACE2 deficiency may expose patients to lung damage. In this Review, we use established and emerging evidence based on the findings of previous studies and researches to propose a testable hypothesis that Combination of chemopreventive agents (All Trans Retinoic acid and Tamoxifen) can be tested to prevent inflammatory complication in severe acute respiratory syndrome coronavirus 2 infection via two mechanisms by inhibiting bradykinin B1,B2 receptors expression and upregulating the depleted ACE2 in COVID-19 . Bradykinin B1 receptors are not expressed under physiological conditions but are induced under inflammatory conditions. Here we hypothesize that permanent attack and invasion of COVID-19 to lung epithelial cells via binding to ACE2 leads to tissue injury and inflammation and that increases BK levels and BK-B2-receptor (B2R) stimulation A study reported that tissue injury and inflammation increases BK levels and BK-B2-receptor (B2R) stimulation. We suggest that Bradykinin mediates and induces lung injury, proinflammatory cytokines and inflammation likely precipitates life threatening respiratory complications in COVID-19. Further experiments showed that BK treatment stimulated IL-6 production On the other hand a study reported that cells treated with Retinoic acid and Tamoxifen for 48 h significantly decreased the BK-B2 receptor protein levels (70.3 ± 0.6% vs. 100% of control, P \< 0.05). Retinoids inhibit bradykinin B1 receptor-sensitized responses and this action could participate in their anti-inflammatory and immunomodulatory effects. In addition retinoic acid, is known to possess in vivo anti-inflammatory, anti-platelet and fibrinolytic activities. A study investigated the in vitro thrombin and platelet aggregation inhibitory activities of retinoic acid and retinaldehyde.Retinoic acid, retinaldehyde and retinol exhibited potent inhibition of thrombin, with IC50 values of 67μg/ml, 74μg/ml and 152μg/ml, respectively for the inhibition of thrombin (Sigma); and 49μg/ml, 74μg/ml and 178μg/ml, respectively for the inhibition of thrombin (plasma). Amongst vitamin A and its derivatives, retinoic acid showed the highest inhibition of both the forms of thrombin. Beside the effectiveness of TAM on cancer cells, it also has other effects on numerous microbes including parasite, fungi, bacteria, and some viruses such as Ebola virus and human immunodeficiency virus (HIV).Furthermore Tamoxifen can block the action of interleukin 6 and inhibit neutrophils. A study demonstrated that tamoxifen has side effects associated with neutropenia. Since tamoxifen can cause neutropenia and subsequently influence the neutrophil-to-lymphocyte ratio (NLR) value In addition it has anti malarial effect similar to chloroquine In conclusion Keywords: COVID 2019 , Retinoic acid, Endosomal toll-like receptor 3,T Cells, IFN type1, AT1, ACE2,TMPRSS2

Timeline

Start

2020-11

Primary completion

2020-12

Completion

2020-12

Drugs

Indications