In vitro and in silico anti-leukemic activity of 2-amino-6-nitro-4-(4-oxo-2-thioxothiazolidin-5-yl)-4H-chromene-3-carbonitrile (ANC) through inhibition of anti-apoptotic Bcl-2 proteins.

An array of 4H-chromene derivatives have been reported for anticancer properties but their selectivity and mode of anticancer activity are unexplored. In this context, we have investigated a biologically active synthetically designed 4H-Chromene carbonitrile derivative, 2-amino-6-nitro-4-(4-oxo-2-thioxothiazolidin-5-yl)-4H-chromene-3-carbonitrile (ANC) that is strongly and selectively inhibited Bcl-2 over expressing human leukemic (HL-60 and K562) cells for its interaction and elucidated the mode of action. The interaction of ANC was investigated against the antiapoptotic proteins such as Bcl-2, Bax, Bcl-xL and Bcl-w that were overexpressed in leukemic cells using in silico and fluorescent spectroscopic studies. Fluorescent spectroscopic based interaction studies showed that the derivative had strong interaction with Bcl-xL followed by Bcl-2/Bax and least interaction with Bcl-w. Based on the results, the ANC had strong interactions with antiapoptotic Bcl-2 and Bax proteins than the Bcl-xL and Bcl-w proteins. The in vitro biological validation of ANC treated leukemic cells showed downregulation of Bcl-xL than Bcl-2 but least effect on Bcl-w proteins. Furthermore, the ANC had possible four isomers as RR, RS, SR and SS isomers. Among them, RS isomer of ANC had shown more active that correlated with biological interactions and gene expression studies of ACN with oncoproteins. These results confirmed the induction of apoptosis by RS-ACN isomer through inhibition of antiapoptotic machineries of leukemic cells confirming the antiapoptotic Bcl-2 inhibitory activities.Communicated by Ramaswamy H. Sarma.

Predictive medicinal metabolites from Momordica dioica against comorbidity related proteins of SARS-CoV-2 infections.

Momordica dioica have proven medicinal potential of antidiabetic, antiviral and immune stimulating properties. Flavonoids and triterpenoids from M. dioica were more extensively investigated for antiviral, antidiabetic and immunomodulatory activities. In this present study, we have predicted the reported bioactive flavonoids and triterpenoids of the plant against the SARS-CoV-2 main protease, RNA-dependent RNA polymerase (RdRp), spike protein, angiotensin converting enzyme (ACE-2) receptor and dipeptidyl peptidase (DPP4) receptor through molecular docking and in silico ADME predictions methods. According to the binding affinities, the two triterpenoids, hederagenin and oleanolic acid exhibited the best docking scores with these proteins than the catechin and quercetin with compared to standard remdesivir, favipiravir and hydroxychloroquine. The in vitro protein-drug studies have also showed significant interaction of catechin and quercetin compounds than standard drugs. The in silico binding studies correlated with the in silico binding studies. Further, M. dioica being used as antidiabetic and its metabolite had significant interaction with DDP4, a comorbidity protein involved in aiding the viral entry. Out of all the natural ligands, quercetin was reported relatively good and safe for humans with high gastrointestinal tract permeability and poor blood brain barrier crossing abilities. Hence, M. dioica phytocompounds reflects promising therapeutic properties against SARS-CoV-2 infections under comorbid conditions such as diabetes, cardiovascular disease and kidney disorders.Communicated by Ramaswamy H. Sarma.