{"paper_id":"7522287e-a2b8-47e1-9e17-258c7f414ab3","body_text":"Inflammation is the body’s defense response mediated by innate immune system in the terms of cellular homeostasis against foreign pathogenic agents that damage cellular homeostasis. The biological mechanism underlying inflammation consists of three stages, namely initiation, regulation, and resolution. These three mechanisms are strictly regulated in order to maintain cellular and physiological homeostasis. Macrophages as cells located at the infection site will recognize infection and secrete proinflammatory cytokine to attract immune cells, among others, leukocytes and lymphocytes, thus triggering inflammation ( 1 - 4 ). The master regulator from innate immune system is a NF-kB system signal used as immunity defense ( 5 ).\nEndometriosis is a disease characterized by the growth of endometrial tissue (endometrial and stromal gland cells) outside the uterine cavity. The development of this disease is influenced by estrogen hormone. The estrogen hormone can trigger an inflammatory reaction that may adversely affect the woman’s life ( 6 ). Endometriosis may occur in all women from adolescent, reproductive age, even menopause, but approximately 20-30% frequently occurs at reproductive age. It is found that one of ten women of reproductive age of 15-49 years may suffer from endometriosis. Endometriosis becomes a scourge for reproductive age women because it is estimated that approximately 50-70% of women may have complaints of chronic pelvic pain and approximately 38% are diagnosed with infertility ( 7 ).\nEndometriotic lesions locally produce estradiol E2 through aromatase activation for the survival of ectopic endometriosis and stimulation of proinflammatory cytokines ( 8 ). Proinflammatory cytokines secreted by macrophages in the peritoneum and ectopic endometrial cells are potentially angiogenic for the development of endometriosis ( 9 ). Proinflammatory cytokines (TNF-α) released by peritoneal macrophages activate transcription factors such as NF-kB through IkB peptide p50/p65. Active transcription factors may enter the cell nucleus to induce gene transcription and encode the products ( 10 ,  11 ).\nScurrula atropurpurea  plants or known by Javanese as tea parasite are parasitic plants for tea ( Thea sinensis ). This plant from generation to generation has been used by the Javanese people as a cancer drug ( 12 ,  13 ).  Scurrula atropurpurea  inhibits cervical cancer cell growth through a mechanism of intrinsic pathway apoptosis ( 14 ).  Scurrula atropurpurea  also acts as an antioxidant. Some of active components of this plant are antioxidants of quercetin, quercitrin, and kaempferol ( 15 - 19 ). On the one hand, antioxidant compounds can suppress oxidative stress. On the other hand, moderate oxidative stress activates the inflammatory pathway. Thus, antioxidants of this plant also can potentially inhibit inflammation ( 20 ). Until now, the potential of  Scurrula atropurpurea  for endometriosis treatment has not been revealed. If  Scurrula atropurpurea  is an anti-inflammatory, it can potentially inhibit the inflammatory pathways involved in endometriosis.\n\nTherefore, the purpose of this study was to analyze the anti-inflammatory effects from plant active compounds of  Scurrula atropurpurea  through molecular docking between active compounds and the NFkB-IkB complex with IKK.\n\nThe National Center for Biotechnology Information (NCBI) Database, United States National Library of Medicine (NLM), National Institute of Health (NIH) (http://www.ncbi.nlm.nih.gov) represent a source of amino acid sequences making up protein of NF-kB (GI: 1018443262), IkB kinase-b (IKK-beta) (GI: 4185275), and IkB kinase-a (IKK-alpha) (GI: 4185273). PubChem Open Chemistry Database is a source of 3D structures for components of  Scurrula atropurpurea  active compounds, including Aviculin (CID 10391477), Caffeine (CID 2519), Catechin (CID: 9064), Epicatechin (CID: 72276), Kaempferol (CID 5280863), Quercetin (CID 5280343), quercitrin (CID 5280459), rutin (CID 5280805), and theobromine (CID 5429). The 3D structures of the  Scurrula atropurpurea  active compound were obtained in the form of *.sdf file format. This format was converted to a *.pdb file using OpenBabel software ( 21 ).\nThe 3D structure of the target protein was predicted using the SWISS-MODEL web server with the homology modeling method. The 3D protein structures were then validated using Ramachandran plot ( 22 ,  23 ).\nMolecular docking modeling between  Scurrula atropurpurea  active components and target proteins was carried out using HEX 8.0 software ( 24 ). The docking procedure consisted of three stages of visualization, namely rigid-body energy minimization, semi-flexible repair, and finishing refinement in explicit solvent. The docking results were then visualized with Chimera 1.6.2 and Discovery Studio 4.1 softwares.\nMolecular docking results were then visualized using Discovery Studio 4.1, LigPlot + and LigandScout 3.1 softwares ( 25 ,  26 ). Analysis of interactions between protein and ligand was made to see the number and type of chemical bonds formed.\n\nThe docking between nine active compounds of  Scurrula atropurpurea  has been carried out against NFkB-IkB complex. The compounds which are most easily to form a docking with NFkB-IkB complex in sequence are rutin (-314.35 kJ/mol), aviculin (-311.75 kJ/mol), quercetin (-247.11 kJ/mol), quercitrine (-288.36 kJ/mole), catechin (-239.13 kJ/mol), kaempferol (-238.11 kJ/mol), epicatechin (-232.58 kJ/mol), caffeine (-170.13 kJ/mol), and theobromine (-162.28 kJ/mol). The point of interaction, type of bond, and the amount of energy needed by each compound to interact with the NFkB-IkB complex in the interaction process can be seen in  Table 1 .\nTable 2  shows the energy of interaction between NFkB-IkB complex and IKK. The results of this study indicate the energy needed for IKK to interact with NFkB-IkB complex under normal condition (without S. atropurpurea active compound) is -211.95 kJ/mol. The results of  in silico  analysis showed that all active compounds can potentially support the interaction between NFkB-IkB and IKK where by the energy needed to interact is smaller when there is an active compound. The sequences of interactions are including kaempferol (-226.88 kJ/mol), aviculin (-223.17 kJ/mol), caffeine (-219.11 kJ/mol), catechin (-219.04 kJ/mol), epicatechin (-216.75 kJ/mol), quercetin (-220.20 kJ/mol), and quercitrine (-215.16 kJ/mol). For rutin (-185.88 kJ/mol) the bonding energy is greater than without the active compound so the interaction is slower than normal condition (-211.95 kJ/mol).\n\nSome previous studies have proven an involvement of inflammation in endometriosis, which is characterized by an increase in up-regulation of proinflammatory cytokines, TNF-a, IL-1, IL-11, and interferon-g ( 27 ). This increase occurs through activation of transcription factors such as NF-kB which enter the cell nucleus to induce gene transcription and encode the proinflammatory cytokine products ( 10 ,  11 ).\nIn this study, we analyze how the role of  Scurrula atropurpurea  active compounds on the classic NFkB signaling pathway, which involves the complex activity of IkB kinase (IKK) in phosphorylation of NFkB (IkB) inhibitor, so causing IkB to be degraded through the ubiquitination process. Furthermore, NFkB will translocate to nucleus and activate transcription from target genes. The results of this study revealed that various active ingredients of  Scurrula atropurpurea  can interact with NFkB-IkB complex. Of the nine active ingredients of  Scurrula atropurpurea , the ingredients which are most easily to make interaction (which is characterized by low bond energy) in sequence are rutin (-314.35 kJ/mol), Aviculin (-311.75 kJ/mol), quercetin (-247.11 kJ/mol), quercitrine (-288.36 kJ/mol), catechin (-239.13 kJ/mol), kaempferol (-238.11 kJ/mol), epicatechin (-232.58 kJ/mol), caffeine (-170.13 kJ/mol), and theobromine (-162.28 kJ/mol). This indicates that nine active ingredients of  Scurrula atropurpurea  can form the complexes with NFkB-IkB in the cytoplasm. Previous studies have proved the docking between piperine and NFkB, the interaction energy of (-24.685 kcal/mol) and have hydrophobic and hydrogen bonds, indicating NFkB inhibitors ( 28 ). Interestingly, almost all interactions between the active ingredients of  Scurrula atropurpurea  and NFkB-IkB complex will facilitate its interaction with the IKK. This indicates that the active ingredient cannot inhibit NFkB activation. For rutin, the energy interaction is greater than in normal condition, so it can be an NFkB activation inhibitor. This finding is consistent with previous studies, stating that rutin is capable to suppress phosphorylation and IkB degradation ( 29 ,  30 ). This finding is contrary to previous findings that catechin, theobromine, quercitrin, and caffeine have been proven capable to inhibit NFkB activation ( 31 - 34 ).\n\nThus it is concluded that one of the active ingredients of  Scurrula atropurpurea  which can potentially act as anti-inflammatory substance is rutin thereby it can be isolated and used as an alternative ingredient for inhibiting inflammation in endometriosis.","source_license":"CC0","license_restricted":false}