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Swamy, K. V.

Publications and source records attributed to Swamy, K. V..

2 recordsLinked to original sources
bioRxiv2020

An intracellular tripeptide Arg-His-Trp of serum origin detected in MCF-7 cells is a possible agonist to β2 adrenoceptor

BackgroundThe need of agonists and antagonists of {beta}2 adrenoceptor ({beta}2AR) is warranted in various human disease conditions including cancer, cardiovascular and other metabolic disorders. However, the sources of agonists of {beta}2AR are diverse in nature. Interestingly, there is a complete gap in the exploration of agonists of {beta}2AR from serum that is a well-known component of culture media which supports growth and proliferation of normal and cancer cells in vitro. MethodsIn this paper, we employed a novel vertical tube gel electrophoresis (VTGE)-assisted purification of intracellular metabolites of MCF-7 cells grown in vitro in complete media with fetal bovine serum (FBS). Intracellular metabolites of MCF-7 cells were then analyzed by LC-HRMS. Identified intracellular tripeptides of FBS origin were evaluated for their molecular interactions with various extracellular and intracellular receptors including {beta}2AR (PDB ID: 2RH1) by employing molecular docking and molecular dynamics simulations (MDS). A known agonist of {beta}2AR, isoproterenol was used as a positive control in molecular docking and MDS analyses ResultsWe report here identification of a few novel intracellular tripeptides, namely Arg-His-Trp, (PubChem CID-145453842), Pro-Ile-Glu, (PubChem CID-145457492), Cys-Gln-Gln, (PubChem CID-71471965), Glu-Glu-Lys, (PubChem CID-11441068) and Gly-Cys-Leu (PubChem CID145455600) of FBS origin in MCF-7 cells. Molecular docking and MDS analyses revealed that among these molecules, the tripeptide Arg-His-Trp shows a favorable binding affinity with {beta}2AR (-9.8 Kcal/mol). Furthermore, agonistic effect of this tripeptide, Arg-His-Trp is significant and comparable with that of a known agonist of {beta}2AR, isoproterenol. ConclusionIn conclusion, we identified a unique Arg-His-Trp tripeptide of FBS origin in MCF-7 cells by employing a novel approach. This unique tripeptide Arg-His-Trp is suggested to be a potential agonist of {beta}2AR and it may have applications in the context of various human diseases like bronchial asthma and chronic obstructive pulmonary disease (COPD). NOVELTY & IMPACT STATEMENTSO_LIThis paper reports on a novel vertical tube gel electrophoresis (VTGE) system that assisted in the purification and identification of a few intracellular tripeptides in the in vitro grown breast cancer cells, MCF-7ls. C_LIO_LIMolecular docking and molecular dynamics simulation analyses strongly suggest that the tripeptide Arg-His-Trp among others forms the most stable ligand-protein complex with {beta}2 adrenoceptor ({beta}2AR). Its binding affinity and the nature of molecular interactions are comparable or even better than the known agonists of {beta}2AR. C_LIO_LIThis tripeptide Arg-His-Trp is predicted to show manyfold less cytotoxicity, mutagenicity, cardiotoxicity, drug-drug interactions, microsomal stability, and drug-induced liver injury over the other known agonists of {beta}2AR. C_LIO_LIThe tripeptide Arg-His-Trp is therefore suggested as an effective agonist of {beta}2AR and this may be validated in future, in preclinical and clinical models. C_LI

cell biology↗
bioRxiv2020

Novel antiproliferative tripeptides block AP-1 transcriptional complex by in silico approach

BACKGROUNDThe complexity and heterogeneity at genetic, epigenetic and microenvironment levels are key attributes of tumors. Genetic heterogeneity encompasses one of key factors at transcriptional gene regulation that promote abnormal proliferation, invasiveness and metastasis. Among various key pro-tumor transcriptional complexes, activating protein-1 (AP-1) transcriptional complex controls the transcriptional expression of key oncogenes in cancer cells. Therefore, an avenue to search for a chemical inhibition approach of the AP-1 transcriptional complex is warranted in cancer therapeutics. METHODSTo achieve chemical inhibition of AP-1 transcriptional complex, we report novel tripeptides identified from the goat urine DMSO fraction as potential agents that bind to AP-1 responsive TPA element and heterodimer c-Jun:c-Fos. Novel tripeptides enriched GUDF were tested against DNA substrates to assess DNA metabolizing activity. Further, Novel tripeptides enriched GUDF were treated upon HCT-116 cells to estimate the nature of tripeptides entered into the intracellular compartment of HCT-116 cells. Here, we report on a novel methodology that employ VTGE assisted intracellular metabolite purification and is analyzed with the help of LC-HRMS technique. Post purification of intracellular metabolites that included tripeptides of GUDF, these tripeptides from DMSO and GUDF treated HCT-116 cells were subjected to molecular docking and ligand-DNA:AP-1 (PDB ID: 1FOS) interaction study by using bioinformatics tools AutoDock Vina and PyMol. RESULTSGUDF enriched with tripeptides and other metabolites show appreciable instability of DNA substrates plasmid and genomic DNA to an extent of 90%. Interestingly, LC-HRMS analysis of intracellular metabolite profiling of GUDF treated HCT-116 cells reveal the appreciable abundance of tripeptides Glu-Glu-Arg, Gly-Arg-Pro, Gln-Lys-Arg, Glu-Glu-Lys, Trp-Trp-Val. On the other hand, DMSO treated HCT-116 cells show the presence of Ser-Trp-Lys, Glu-Glu-Gln, Glu-Glu-Lys, Ser-Leu-Ser. Interestingly, GUDF treated HCT-116 cells show inhibition of proliferation by more than 70%. Among the identified intracellular tripeptides, Glu-Glu-Arg (9.1 Kcal/Mol), Gly-Arg-Pro (8.8 Kcal/Mol), and Gln-Lys-Arg (6.8) show a precise and strong binding to heptameric TPA response element 5 TGAGTCA 3 and key amino acid residue within the AP-1 transcriptional complex. CONCLUSIONIn summary, this study suggests the potential of novel tripeptides, those are reported from GUDF intracellularly in HCT-116 cells to destabilize the AP-1 transcriptional complex. Data indicate that cellular arrest in HCT-116 cells treated by GUDF is well supported by the molecular docking observations that destabilization of AP-1 complex is linked to reduced growth and proliferation.

cancer biology↗