The goal of the current study was to gain an understanding of the molecular mechanisms underlying the herb Vernonia cinerea activity on hepatoprotective properties used in the Indian traditional medicines by using gene set enrichment analysis, network pharmacology, in-silico docking and simulation study. To understand the relationship between phytoconstituents and protein targets, network pharmacology is the latent approach to determine traditional medicines for the management of several diseases and disorders in which hepatotoxicity is also a major component. Based on the principle that "similar compounds target similar proteins", primarily we predicted the pathways and the proteins which are involved in Isoniazid induced Hepatotoxicity, firstly the proteins which are involved in causing Hepatotoxicity data were retrieved from the Gene card online server further the obtained proteins are queried into the Swiss target prediction to determine the regulated pathways for respective genes, after peer reviewing the pathways which are related to the hepatic disorder were selected and the network were build using the Cytoscape v3.6.1 and further the plant chemical compound was collected from the all available literature and the canonical smiles were retrieved from the PubChem online server and predicted for the positive DLS in which we found 26 phytocompound and their targets were predicted by using Swiss target prediction and Additionally, using the ADVERpred an online server in these server chemical compounds were examined for their potential to cause myocardial infarction, hepatotoxicity, cardiac toxicity, and other serious adverse medication responses and side effects, out of 26 phytocompounds 17 phytocompounds data were available in ADVERpred server in that one compound named Dendrocandin E showed the Pa of 0.61 that means this might cause toxicity, rest were Pa ≤ 0.5, and further the targets were carefully selected only based on probable molecular functions, processes, and pathways of higher significance(p ≤ 0.05). STRING database was used to determine the molecular functions, biological processes, and pathways regulated by the anticipated targets, the pathways were determined by the KEGG pathway which are regulated in the Hepatotoxicity were considered such as HIF-1 signaling pathway, PI3K-Akt signaling pathway, Hepatitis B, Insulin resistance, Hepatitis C, JAK-STAT signaling pathway, Insulin signaling pathway, MAPK signaling pathway, Hepatocellular carcinoma, VEGF signaling pathway, TNF signaling pathway, Non-alcoholic fatty liver disease, Sphingolipid signaling pathway, AMPK signaling pathway, PPAR signaling pathway, Regulation of lipolysis in adipocytes, p53 signaling pathway, NF-kappa B signaling pathway, IL-17 signaling pathway. The pathways mechanism involves, HIF-1 pathway acts different mechanisms in liver damage in ALD it inhibits the protection in intestinal integrity[34, 35], Reduce fatty acid synthesis [36] and promotes lipid accumulation [37], and increases portal pressure [38], through the Akt/HIF-1α pathway [39] and in NAFLD it Inhibit excessive accumulation of liver fat [40] and promotes liver fibrosis [41] Inhibit excessive accumulation of liver fat [40] and Promote liver fibrosis [42]. And AILI acts by Inhibiting Contribute to hemostasis [43], Reduce inflammatory reaction, Improve centrilobular necrosis [44]. And in Viral hepatitis acts Increase autotaxin protein expression [45] and Facilitate HIF-1α-mediated glycolytic adaptation [46], and in HCC acts Promote migration, invasion, metastasis and angiogenesis [47–49] and according to literature, PI3K is an intracellular phosphatidyl inositol kinase involved in a number of cellular processes, including cell division, proliferation, and death as well as glucose transport [50]. The second messenger PIP3 is synthesised in the plasma membrane by PI3K. PIP3 was interacting with the intracellular signal proteins PDK1 and Akt, which led to PDK1 activating Akt. A crucial PI3K downstream effector, Akt, demonstrated antiapoptotic properties by phosphorylating a variety of target proteins and downstream pathways [51]. In certainty, stimulation of the PI3K/Akt pathway increased the transcription activity of NF-κB [52]. In order to release NFB from the cytoplasm, carry out nuclear translocation, activate its target genes, and support cell viability, Akt activated IB kinase (IKK/IB), which led to the degradation of NF-B inhibitor I-B [53]. NF-κB is a crucial transcription factor in the nucleus that plays a role in immunity and inflammation as well as controlling the production of genes that lead to apoptosis.
In the all pathways there are 36 genes were having the similar genes which are responsible for modulating the pathways in which AKT1, PIK3CA, MAPK1, HRAS, and EGFR were found to have top five hub genes with higher edge count within the network and their relation between the Pathway and compound.
After gene ontology, enrichment, and network analysis, we continued the investigation through utilizing molecular docking and MD simulation studies to look at the intermolecular interactions between phytocompounds and anticipated protein targets. As a result, the top five genes i.e., AKT1, PIK3CA, MAPK1, HRAS, and EGFR as they earned the top-scoring node with the highest edge count of 19, 18, 17, 16, and 14 respectively. Thus, these hub genes were carriedforward for the molecular docking based on the highest edge count, and as well as on secondary literature analysis, they were found to be well documented as a therapeutic target for hepatotoxicity and HCC (identified to be involved in the MAPK, PI3-Akt, and Jak-STAT signaling pathways within the network). Information on phytocompounds that target protein targets and regulated pathways is provided in Table S9 (the edge count, or the number of compounds and pathways that connect to a given protein target, was noted). Further for molecular docking the proteins Crystal Structures of AKT1, PIK3CA, MAPK1, HRAS, and EGFR were obtained from PDB having the PDB id: 3O96, 7R9V, 4G6O, 4XVR, and 4I23 respectively and the missing residues were fixed by homology modeling. The molecular docking results of all proteins were shown in table, for EGFR protein discovered to interact with the eight phytochemicals, including Apocynin B, Asebotin, Dendrocandin E, Isoduartin, Kukoamine A, Renifolin, Squalene, and Torachrysone-8-O-beta-D-glucopyranoside were, Apocynin B was shown to have the lowest binding energy of -8.9 kcal/mol by creating six hydrophobic bonds with the residues Leu718, Val726, Ala743, Leu844 (2), and Asp855 as well as two hydrogen bonds with Lys745...=O and Gln791...O.. After obtaining the results Apocynin B were compared with Erlotinib which is known EGFR antagonist [54]. Surprisingly it showed less binding affinity with the EGFR protein having Binding energy of -6.7 kJ/mol via forming one hydrogen bond i.e., MET 793…NH and forming six hydrophobic bonds i.e., LEU 718, VAL726, LYS745, MET766, LEU788, LEU844 residues. Further for molecular dynamics the chemical compound Apocynin B and Erlotinib compound selected for the molecular dynamics study with the best protein molecule EGFR (based on a greater number of chemical compounds having lowest binding energy with the protein were selected) to determine protein structure stability on ligand binding. The Apocynin B_EGFR complex showed stable dynamics after an equilibrium period 40ns, the residues Thr725, Ile740, Ser921, Glu922 showed relatively fewer fluctuations as they participate in stable non-bonded interactions. Although the Ala750, Ser752; Leu1001, Met1002 showed relatively higher fluctuation (~ 5.3 Å; ~6.4 Å), Rg value reveals the stable complex after the 40ns till 100ns, in addition, the SASA exposed initially decrease from 180 nm2 to 170 nm2 denoting decrease in the SASA values complying that the ligand was getting fit into the pocket by forming 7 hydrogen bonds in which 3 were consistent, and in concern with energy contribution revealed 11 residues had significantly contributing for the complex stability. With respect to the Erlotinib_EGFR complex showed stable dynamic from 10ns – 70ns after that the fluctuation were seen till 100ns, when the Rg value, SASA, Hydrogen bonding, and energy contribution of residues compared with the Apocynin B_EGFR complex, Apocynin B_EGFR complex were shown significant results.