key: cord-0910683-lb4hpjfw
authors: Gyebi, Gideon A.; Ogunyemi, Oludare M.; Ibrahim, Ibrahim M.; Afolabi, Saheed O.; Adebayo, Joseph O.
title: Dual targeting of cytokine storm and viral replication in COVID-19 by plant-derived steroidal pregnanes: An in silico perspective
date: 2021-04-18
journal: Comput Biol Med
DOI: 10.1016/j.compbiomed.2021.104406
sha: ff1ef46b9300e419d31200bd8c083265dd952403
doc_id: 910683
cord_uid: lb4hpjfw

The high morbidity and mortality rate of Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2) infection arises majorly from the Acute Respiratory Distress Syndrome and “cytokine storm” syndrome, which is sustained by an aberrant systemic inflammatory response and elevated pro-inflammatory cytokines. Thus, phytocompounds with broad-spectrum anti-inflammatory activity that target multiple SARS-CoV-2 proteins will enhance the development of effective drugs against the disease. In this study, an in-house library of 117 steroidal plant-derived pregnanes (PDPs) was docked in the active regions of human glucocorticoid receptors (hGRs) in a comparative molecular docking analysis. Based on the minimal binding energy and a comparative dexamethasone binding mode analysis, a list of top twenty ranked PDPs docked in the agonist conformation of hGR, with binding energies ranging between −9.8 and −11.2 kcal/mol, was obtained and analyzed for possible interactions with the human Janus kinases 1 and Interleukins-6 and SARS-CoV-2 3-chymotrypsin-like protease, Papain-like protease and RNA-dependent RNA polymerase. For each target protein, the top three ranked PDPs were selected. Eight PDPs (bregenin, hirundigenin, anhydroholantogenin, atratogenin A, atratogenin B, glaucogenin A, glaucogenin C and glaucogenin D) with high binding tendencies to the catalytic residues of multiple targets were identified. A high degree of structural stability was observed from the 100 ns molecular dynamics simulation analyses of glaucogenin C and hirundigenin complexes of hGR. The selected top-eight ranked PDPs demonstrated high druggable potentials and favourable in silico ADMET properties. Thus, the therapeutic potentials of glaucogenin C and hirundigenin can be explored for further in vitro and in vivo studies.

Corona Virus 2 (SARS-CoV-2) [1] . The clinical presentation of SARS-CoV-2 infections ranges from asymptomatic condition or mild symptoms (such as fever, cough, and generalized malaise) in the majority of the cases to severe respiratory failure. The early stage of infection, progresses to interstitial pneumonia and acute respiratory distress syndrome (ARDS) in nearly 10-20% of the cases, especially in the elderlies and people with co-morbidities [2] . The pathophysiology of SARS-CoV-2 infection is a complex mechanism that is known to mobilize several biomolecules of the immune and hematologic systems [3] .

Cytokines are a group of polypeptide signaling molecules responsible for regulating a large number of biological processes via cell surface receptors [4] . The term "cytokine storm", a condition characterized by an exaggerated activation of the immune system was first associated with onset of the graft-versus-host disease [5] and later known to be involved in several viral infections [6] . The exaggerated cytokine release in response to viral infection, has emerged as one of the mechanisms leading to acute respiratory distress syndrome and multiple-organ failure in COVID-19 [7] . In this regard, recent studies have shown that patients with COVID- 19 have higher levels of inflammatory cytokines, such as interleukin (IL)-1β, IL-2, IL-6 IL-7, IL-8, IL-9, IL-10, IL-18, tumor necrosis factor (TNF)-α, granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor, fibroblast growth factor, macrophage inflammatory protein 1, compared to healthy individuals [8] ; circulating levels of IL-6, IL-10, and TNF-α also correlated with illness severity as they were significantly higher in intensive care unit (ICU) patients compared to mild/moderate cases. At this point, antiviral treatment alone is not enough and should be combined with appropriate anti-inflammatory treatment. Antirheumatic drugs, which are tried for managing cytokine storm of SARS-CoV-2 infection include:

corticosteroids, JAK inhibitors, IL-6 inhibitors, IL-1 inhibitors, anti-TNF-α agents, hydroxychloroquine, intravenous immunoglobulin (IVIG), and colchicines [9] .

The interaction of glucocorticoids receptors (GR) and its ligands, glucocorticoids (GCs), have been explored for the modulation of cytokines in acute and chronic inflammatory diseases [10] . Glucocorticoids modulate cytokine expression by several genomic mechanisms. The activated GR complex: (i) binds to the promotor responsive elements, thereby inactivating key pro-inflammatory transcription factors (e.g. AP-1, NF kappa B);

(ii) upregulates the expression of cytokine inhibitory proteins, e.g. I kappa B, which inactivates the transcription factor NF kappa B, thereby suppressing the secondary expression of a series of cytokines; and lastly, (iii) J o u r n a l P r e -p r o o f reduces the half-lives and utility of cytokine mRNAs [11] . Unfortunately, the use of GCs is limited by unwanted severe side effects, such as osteoporosis, disorders of glucose and lipid metabolism, and hypertension [12] .

Therefore, there is an urgent need for the development of natural compounds with higher anti-inflammatory activity compared to standard GCs, alongside antiviral potential and with accompanied no or low toxicity [13, 14] . Janus kinases (JAKs) mediate the signaling of numerous cytokines and growth factors involved in the regulation of inflammation, immunity and hematopoiesis [15] . Among the JAK family members, the JAK1 has the broadest cytokine signaling profile,being the only isoform that pairs with the other three JAKs. The pairing of JAK1with JAK3 regulates the signaling of the gamma common (γc) cytokines. The pairing of JAK1with JAK2 regulates the signaling of type I interferons (IFNα, IFNβ), type II interferon (IFNγ) and the IL-10 family of cytokines [16] . Inhibitors of the JAK-STAT pathway, such as baricitinib and Ruxolitnib, are used for suppressing proinflammatory cytokine production and systemic inflammation. Interleukin-6 (IL-6) is a pleiotropic cytokine. In general, IL-6 inhibitors prevent human IL-6 from binding to IL-6 receptors, thus impeding the formation of immune signaling complexes on cell surfaces [17] .

Along with structural proteins, the SARS viral genomes encode non-structural proteins, including 3chymotrypsin-like protease (3CL pro ), papain-like protease (PLpro), helicase and RNA-dependent RNA polymerase (RdRp) which are important target for the development of therapeutics [18] . The proteolytic processing of the polyproteins is performed by the viral cysteine proteases to yield 16 non-structural proteins; 3CL pro cleaves and modifies the viral polyproteins at 11 sites while PL pro cleaves the first three sites at the Nterminus [4, 19] . The RNA-dependent RNA polymerase (RdRp), is a central component of coronaviral replication/transcription machinery that catalysis RNA-template dependent formation of phosphodiester bonds between ribonucleotides In our recent work, we have demonstrated the potential of some natural compounds as inhibitors of these proteins [20] [21] [22] .

Recently, dexamethasone, a potent synthetic anti-inflammatory glucocorticoid was declared as the world's first treatment proven effective in reducing the risks of death through cytokine storm among severely ill COVID-19 patients based on clinical trial results [23, 24] . Through computational and biological comparison, few plant- [25] , guggulsterone [26] , boswellic acid [27] , withaferin A [28] and diosgenin [29] have a common cyclopentanoperhydrophenanthrene steroid ring structure. Pregnanes are naturally occurring C 21 steroidal J o u r n a l P r e -p r o o f compounds that have been documented with wide range of bioactivities including anti-inflammatory activity [22, [30] [31] [32] . Due to the present COVID-19 pandemic, there is urgent need for such plant-derived steroids that may possess dual interference with cytokine storm and viral replicase/transcriptase complex but with fewer side effects. Thus, the aim of this study was to screen an in-house library of plant-derived steroidal pregnanes for hGR agonist using a comparative molecular docking approach.

Materials and methods

The three-dimensional (3D) structure of human glucocorticoid receptors in the agonist conformation (hGRag) (PDB ID: 4UDC), human glucocorticoid receptors in the antagonist conformation (hGRagt) (PDB ID: 1NHZ), human Interleukin-6 (hIL-6) (PDB ID: 1ALU), human Janus kinase 1(hJAK1) (PDB ID: 6BBU), SARS-CoV-2 3chymotrypsin-like protease (s3CL pro ) (PDB ID: 6Y84), SARS-CoV-2 papain-like protease (sPL pro ) (PDB ID:

6W9C) and SARS-CoV-2 RNA-dependent RNA polymerase (sRdRp) (PDB ID: 6M71) were retrieved from the Protein Databank (http://www.rcsb.org).

The crystal structures of the of proteins were processed by removing existing ligands and water molecules while missing hydrogen atoms were added according to the amino acid protonation state at pH 7.0 utilizing Autodock version 4.2 program (Scripps Research Institute, La Jolla, CA). Thereafter, non-polar hydrogens were merged while polar hydrogens were added to each protein. The process was repeated for each protein and subsequently saved into a dockable pdbqt format for molecular docking.

PDPs (117) and dexamethasone as negative control) was further conducted. Both hGRagand hGRagtwere co-crystallized with dexamethasone and mifepristone (the positive controls) respectively. The PDPs, reference compounds and the hGR proteins were loaded into PyRx (Python prescription) 0.8 [35] with the incorporation of Autodock vina [36] . For each of the docking steps, the ligands were imported via the OpenBabel [37] , a plug-in tool in PyRx 0.8. The Universal Force Field (UFF) was used as the energy minimization parameter and conjugate gradient descent as the optimization algorithm. The binding site coordinates of the active site regions of the hGRag as defined by the grid boxes were used for docking analysis (table 1a) . All the other parameters were kept as default. After the completion of the docking process, the binding affinities of the protein for the compounds for the selected clusters were recorded. The compounds were then ranked by their binding energies.

Using the same protocol above, the top twenty PDPs with the lowest binding energies to the hGRag in the agonist conformation and the reference inhibitors were docked to the active region of five proteins: human interleukin-6, human janus kinases, SARS-CoV-2 3-chymotrypsin-like protease, SARS-CoV-2 papain-like protease and SARS-CoV-2 RNA-dependent RNA polymerase as defined by the grid boxes ( J o u r n a l P r e -p r o o f

Molecular Dynamics Simulation (MDS) was performed on the hGR in the agonist conformation (apo protein),

Dex and top-two PDPs complexed with hGRag protein using NAMD software version 2.13 [38] . Necessary files for MDS were generated using CHARMM-GUI webserver [39, 40] . For each complex or apo protein, the system was minimized for 10000 steps in constant number of atoms, constant volume and constant temperature (NVT) ensemble then a production run for 100 ns in NVT ensemble was performed. Temperature was set to be 

Molecular Mechanincs -Generalized Born Surface Area (MM-GBSA) implemented in Ambertools 17 is utilized to calculate the binding free energy in Dex and the top two-ranked pregnanes complexed with hGRag [42, 43] . All frames (1000 frame) were used and igb parameter was set to 5, the default value. Saltcon parameter was set to 0.154 M while keeping the rest of the parameters as default. Binding affinity decomposition was used to know the contribution of each amino acid in the binding affinity.

TTClust version 4.7.2 was used to cluster the trajectory automatically according to the elbow method, a representative structure for each cluster was produce [44] . These representative conformations were analyzed using Protein Ligand Interaction Profiler (PLIP) for pregnane atom-amino acid residue interactive analysis [45] . 

The binding affinities from the docking analysis of the proteins for the PDPs (117) and the reference compounds are shown in Table S1 (supplementary material). Based on the minimum binding energies and interactions with catalytic residues, the top twenty PDPs with binding energies ranging from -9.8 to -11.2 Kcal/mol for hGRag was compared to the binding energies of the controls (positive control -dexamethasone = -12.2 Kcal/mol and negative control -mifepristone = -6.0 Kcal/mol; Figure 1 ). Using competitive docking approach,these results were compared with the results obtained from the docking analysis of the top twenty PDPs with the antagonist conformation of the same protein (hGRagt). The binding energies of the positive control (mifepristone: -11. 5

Kcal/mol), negative control (dexamethasone: -8.7 Kcal/mol)and the top twenty PDPs (between -7.7 and -8.8

Kcal/mol) are presented in Table S1 (supplementary material) and Figure 1 . It was also observed that the binding affinities of hGRag for glaucogenin C, hirundigenin and bregenin (-11.2, -10.8 and -10.6 Kcal/mol respectively), the top three PDPs, were higher compared to those of hGRagt for them (-8.8, -8.7 and -8.7

Kcal/mol respectively).

From the interaction of the top twenty ranked PDPs with hGRag, hIL-6, hJAK1,s3CL pro , sPL pro and sRdRp, top three PDPs with the lowest binding energies for each of the proteins were obtained, yielding a combined list of eight pregnanes: bregenin, hirundigenin, anhydroholantogenin, atratogenin A, atratogenin B, glaucogenin A, glaucogenin C and glaucogenin D. From this list, glaucogenin C, hirundigenin, glaucogenin A and glaucogenin D were part of the top three ranked PDPs with least binding energies for at least two proteins, while glaucogenin C, with the least binding energy for hGRag, was listed among the top three ranked PDPs for hIL-6, hJAK1, sPL pro and sRdRp, thereby exhibiting multiplicity of binding properties. It was also observed that apart from GR and JAK, the three top pregnanes for each protein had binding energies for other proteins that were lower than those of the reference compounds.

The amino acid interactions of hGR in the agonist conformation, hIL-6, hJAK,s3CL pro , sPL pro and sRdRp with 

The stability, structural/conformational fluctuations that occurred in the hGRag (apo protein), PDPs-hGRag and Dex-hGRag systems were monitored in a simulated dynamic environment. The apo form and two complexes of hGRag with glaucogenin C and hirundigenin were used in a MDS study for 100 ns in NVT ensemble. The results were analyzed using VMD Tk console scripts to calculate RMSD, RMSF RoG, SASA, and H-bond.

The RMSD is a plausible measure of protein stability.The RMSD plots indicate how much each frame is Table 4 shows the results of the number of clusters that were generated and the interactions at different clusters, using a J o u r n a l P r e -p r o o f

From the docking analysis, eight plant pregnanes (bregenin, hirundigenin, anhydroholantogenin, atratogenin A, atratogenin B, glaucogenin A, glaucogenin C and glaucogenin D) with high binding tendencies to hGRag with corresponding high binding tendencies to hIL-6, hJAK1, s3CL pro , sPL pro , and sRdRp were subjected to the predictive drug-likeness and ADMET (Absorption, Distribution, Metabolism, Excretion, and Toxicity) filtering analyses. The results for the predictive filtering analyses are presented in Table 5 .

Parallel advances in protein crystallography and various virtual-screening software for the modeling of ligandreceptor interactions have enhanced computer-aided drug design [49] . In this study a structure based virtual- [50, 51] . The polar residues on the LBP interacted with the dexamethasone and the top ranked PDPs via several hydrogen bonds [51] . The binding of the amino acid residues on helix 12 and the loop preceding helix 12 have been earlier hypnotized to stabilize the helix in the active conformation that could serve as the molecular basis for the ligand-dependent activation of GR [52] . Among the several amino acids involved in the interactions, Cys-736 has been implicated in the interactions with heat shock proteins [52] , Tyr-735, has been shown to be important for transactivation [53] , while Gln-642 have been reported to play a unique role in steroid recognition [52] . In addition to the steroid structures of glucocorticoids, the 3´-carbonyl oxygen, 2´-carbonyl oxygen, double bonds between C4 and C5, 17ʹ hydroxyl group and 21ʹ hydroxyl group, are critical for anti-inflammatory potency and glucocorticoid receptor affinity [54] . [11] . IL-6 is a major causative factor of inflammatory disease and it is a promising target, as well as its signaling pathways; however, orally available small-molecule drugs specific for IL-6 have not been developed [55] . From the PDPs with high binding tendencies to hGRag, three PDPs (atratogeninA, glaucogenin C and anhydroholantogenin) exhibited the lowest binding energy poses for hIL-6 in the same binding site as observed for the co-crystallized ligands (tartaric acid) of hIL-6. In a similar study, furosemide exhibiting the same binding mode as tartaric acid was further found to inhibit hIL-6 activity in vitro. [56] . From the X-ray crystal diffraction of hIL-6 structure, it was shown to contain four alpha helices (helices A, B, C, and D), which were linked with loops. The receptor-binding domain is located at the C-terminus (residues 175-181) [57] , in which ARG 179 is known to be the key residue [57] .

in receptor binding and signal transduction [58] . Compounds that interact strongly with residue ARG 179 may interfere with the binding of the receptor to its ligands [59] , thus these PDPs may proffer anti-inflammatory activity via hIL-6 inhibition. The Janus kinases (JAK) family of proteins function as critical mediators of cytokine signaling from membrane receptors to various signal transducers and activators of transcription (STAT) family of proteins [60] . Activation of STATs by the JAK kinases promotes the transcriptional activation of target genes controlling cell proliferation and survival, angiogenesis, and immune function [61] . Some JAK family inhibitors such as tofacitinib [62] and ruxolitinib [63] have progressed into clinical trials, and FDA approvals. In comparison with the reference inhibitor, ruxolitnib, the top-three ranked PDPs (atratogenin B, hirundigenin, glaucogenin C) with the best binding modes, for which hJAK1 had the highest affinities, 

The RMSD plots showed that the binding of glaucogenin C and hirundigenin in the same manners as Dex to the active region of hGRag still preserved the structural integrity of the protein [78] . The

The RMSF plots indicates the flexibility of different regions of a protein and the amino acid residue along the trajectory, which can be related to crystallographic B factors [78] . Despite the various efforts to improve current glucocorticoids and anti-inflammatory drugs, they still pose significant side effects [83] , Hence the top-docked PDPs to various proteins were subjected to in silico physiochemical and ADMET analysis. The eight top-ranked PDPs fulfilled the all the requirements for the five physicochemical filtering analysis as reported by Lipinski [84] Ghose [85] , Veber [86] , Egan [87] and Muegge [88] thereby suggesting favourable physicochemical/druggable properties. The top-eight ranked PDPs expressed J o u r n a l P r e -p r o o f positive and high probability of human intestinal absorption and non-substrate but inhibitor of the permeabilityglycoprotein (P-gp). These PDPs are predicted to be well absorbed into the blood stream subverting the capability of P-gp to pump them back into the intestinal lumen, bile ducts, urine-conducting ducts and capillaries respectively [89] . The blood brain barrier (BBB) penetration descriptor, predicts the ability of the PDPs to penetrate the blood brain barrier. The top-eight PDPs displayed the properties that suggested their ability to cross the BBB. SARS-CoV-2 has been reported to infect the brain, thus indicating its ability to cross the BBB [90] , these PDPs may cross the BBB for to exert an overall viral clearance.

The top-eight PDPs displayed a probability of at least 65 % ability to be bond to the plasma protein, suggesting their ability to be transported by these proteins. The estimated half-life time (less than 2 hours) and clearance ratefall within the moderate range. The three phytochemicals presented a tolerable LD 50 between (51~500 mg/kg). The hERG channel plays a vital role in the repolarization and termination stages of action potential in cardiac cells [91] . Compounds that block the hERG channel may cause cardiotoxicity [92] . The top-eight PDPs exhibit low probability of being a potential hERG channel blockers, suggesting that they may not cause hERG channel-related cardiotoxicity [92] . Using the mutagenicity and skin sensitization descriptors, the top-eight PDPs did not display the properties to be mutagenic in silico, thereby suggesting that they may not cause genetic mutations, which do initiate the pathophysiology of other diseases. The impact of the PDPs on the liver phase I drug metabolism was also analysed using the various cytochrome P450 descriptors. The top-eight PDPs demonstrated no inhibitory potential for the various cytochrome P450, thus may not adversely affect phase I drug metabolism in the liver. ADME/tox analysis indicated high aqueous solubility, ability to pass the high human intestinal absorption, low acute oral toxicity with a good bioavailability score. Therefore this natural plant pregnane may be considered to be non toxic with druggable potential.

In this study we employed a competitive docking approach to screen 117 plant derived pregnanes (PDPs) for Human glucocorticoid receptors in the agonist conformation (hGRag), human glucocorticoid receptors in the antagonist conformation (hGRagt), human Interleukin-6 (hIL-6) human Janus kinase 1(hJAK1), SARS-CoV-2 3chymotrypsin-like protease (s3CL pro ), SARS-CoV-2 papain-like protease (sPL pro ) and SARS-CoV-2 RNAdependent RNA polymerase (sRdRp). hGRag -Dexamethasone No.

Apo protein Protein -Dexamethasone complex

Protein -Glaucogenin C complex Protein -Hirundigenin complex J o u r n a l P r e -p r o o f 

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Stick representations of ligands are coloured red while interacting amino acids are in grey colour (a) Ritonavir (reference inhibitor) (b)glaucogenin D (c) hirundigenin (c) anhydroholantogenin. Types of interactions are represented by green-dotted lines: H-bonds; light purple-dotted line: hydrophobic interactions (Pi-Alkyl, Alkyl & pi-stacking); purple-dotted line: Pi-Pi T Shaped; yellow-dotted lines: Pi-sulphur interactions, pi-stacking interactions

Amino acid interactions of pregnanes in binding cavity of RNA-dependent RNA polymerase of SARS-CoV-2. Stick representations of ligands are coloured yellow while interacting amino acids are in grey colour(a) remdesivir (reference inhibitor) (b) glaucogenin A (c) glaucogenin D (c) glaucogenin C. Types of interactions are represented by green-dotted lines: H-bonds; light purple-dotted line: hydrophobic interactions (Pi-Alkyl, Alkyl & pi-stacking); purple-dotted line: Pi-Pi T Shaped; yellow-dotted lines: Pi-sulphur interactions, pi-stacking interactions

The high morbidity and mortality rate of Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2) infection arises majorly from the Acute Respiratory Distress Syndrome (ARDS) and "cytokine storm" syndrome, which is sustained by an aberrant systemic inflammatory response and elevated pro-inflammatory cytokines. Thus, the identification of compounds which target multiple proteins in the virus and exhibit anti-inflammatory activity will enhance the development of effective drugs against the disease. In this study, we carried out an in silico evaluation of some plant-derived pregnanes for their activities against selected human pro-inflammatory and SARS-CoV-2 replication proteins targets. This was carried out by a virtual screening of an in-house library of steroidal plant-derived pregnanes (PDPs). One hundred and six (106) PDPs were docked into the active regions of human glucocorticoid receptors (hGRs) in the agonist (hGRag) and antagonist (hGRagt) conformation, in a competitive molecular docking approach. Based on the minimal binding energy and a comparative dexamethason binding mode analysis, a hit-list of the top twenty ranked PDPs that were docked in the agonist conformation of hGR, with binding energies ranging between -9.8 and -11.2 Kcal/mol, was defined. The top twenty ranked PDPS were further analyzed for interactions with the human Janus kinases 1 andInterleukins-6 (hJAK1 and hIL-6 respectively), and SARS-CoV-2 3-chymotrypsin-like protease, Papain-like protease and RNA-dependent RNA polymerase (3CLpro, PLpro and RdRP respectively). For each of the 6 targeted proteins (3 humans and 3 SARS CoV-2), the top three ranked PDPs were selected, to give a sum of eight PDPs (bregenin, hirundigenin, anhydroholantogenin, atratogenin A, atratogenin B, glaucogenin A, glaucogenin C and glaucogenin D) with multiplicity of high binding tendencies to the catalytic residues of different targets. From this eight PDPs, glaucogenin C and hirundigenin having the highest agonist tendencies to the hGR were further subjected to a 100 ns atomistic molecular dynamics simulation. A high degree of structural stability was observed from molecular dynamics simulation analyses of glaucogenin C and hirundigenin complexes of hGRag. A further clustering of the MDS trajectories of the complexes of glaucogenin C and hirundigenin with the hGRag shows that the interactions of these PDPS with the active site residues of hGRag were preserved in different representative structures of the clusters. The selected top-eight ranked PDPs demonstrated favourable druggable properties over the Lipinski, Veber, Ghose, Egan and Muegge predictive filters. In the same vein the 8 PDPs displayed favorable in silico ADMET properties over a wide range of predictive molecular descriptors, such as, ability to pass the blood brain barriers, high intestinal absorption, non-substrate to the permeability glycoprotein, non hERG blockers, non inhibitors of the cytochrome p450 etc. Thus, these promising hGRag agonists, especially glaucogenin C and hirundigenin, with potential antiinflammatory and SARS-CoV-2 replication inhibitory activity is recommended for lead optimization for drug candidate and further evaluation in an in vitro and in vivo experiment.

The high morbidity and mortality rate from Coronavirus disease 2019 (COVID-19) arises majorly from acute respiratory distress and "cytokine storm" syndrome.Using competitive docking approach, 103 plant derived pregnanes (PDPs) were screened for human glucocorticoid receptors agonist, with a dual inhibitory potential against SARS-CoV-2 replication target proteins and pro-inflammatory cytokines Eight PDPs with high agonist binding tendencies to the human glucocorticoid receptors displayed different levels of multiplicity of inhibitory potentials to two other pro-inflammatory targets and three SARS-CoV-2 therapeutic targets, From the 8 PDP, glaucogenin C and hirundigenin demonstrated high degree of structural stability in a simulated dynamics environment, alongside favourable druggable and in silico ADMET