Determination of tyrosinase-cyanidin-3-O-glucoside and (-/+)-catechin binding modes reveal mechanistic differences in tyrosinase inhibition

Prognostic role of TEAD4 in TNBC: in-silico inhibition of the TEAD4-YAP interaction by flufenamic acid analogs

Triple-negative breast cancer (TNBC) poses a significant global health challenge due to its highly aggressive nature and invasive characteristics. Dysregulation of the Hippo pathway, a key regulator of various biological processes, is observed in TNBC, and its inhibition holds promise for impeding cancer growth. This in-silico analysis investigates the role of Transcriptional Enhanced Associate Domain 4 (TEAD4) in TNBC and its interaction with Yes Associated Protein (YAP) in cancer progression. Our results demonstrate that TEAD4 upregulation is linked to poor prognosis in TNBC, emphasizing its critical role in the disease. Moreover, we identify CID44521006, an analog of Flufenamic acid, as a potential therapeutic compound capable of disrupting the TEAD4-YAP interaction by binding to the YAP-binding domain of TEAD4. These findings underscore the significance of TEAD4 in TNBC and propose CID44521006 as a promising candidate for therapeutic intervention. The study contributes valuable insights to advance treatment options for TNBC, offering a potential avenue for the development of targeted therapies against this aggressive form of breast cancer.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s40203-024-00239-8.

Targeting neuroblastoma by small-molecule inhibitors of human ALYREF protein: mechanistic insights using molecular dynamics simulations

Neuroblastoma is a tumour of the sympathetic nervous system mainly prevalent in children. Many strategies have been employed to target several drug-targetable proteins for the clinical management of neuroblastoma. However, the heterogeneous nature of neuroblastoma presents serious challenges in drug development for its treatment. Albeit numerous medications have been developed to target various signalling pathways in neuroblastoma, the redundant nature of the tumour pathways makes its suppression unsuccessful. Recently, the quest for neuroblastoma therapy resulted in the identification of human ALYREF, a nuclear protein that plays an essential role in tumour growth and progression. Therefore, this study used the structure-based drug discovery method to identify the putative inhibitors targeting ALYREF for the Neuroblastoma treatment. Herein, a library of 119 blood-brain barrier crossing small molecules from the ChEMBL database was downloaded and docked against the predicted binding pocket of the human ALYREF protein. Based on docking scores, the top four compounds were considered for intermolecular interactions and molecular dynamics simulation analysis, which revealed CHEMBL3752986 and CHEMBL3753744 with substantial affinity and stability with the ALYREF. These results were further supported by binding free energies and essential dynamics analysis of the respective complexes. Hence, this study advocates the sorted compounds targeting ALYREF for further in vitro and in vivo assessment to develop a drug against neuroblastoma.Communicated by Ramaswamy H. Sarma.

Active site determination of novel plant versatile peroxidase extracted from Citrus sinensis and bioconversion of β-naphthol

A ligninolytic peroxidase called versatile peroxidase, VP, (EC 1.11.1.16) is an iron-containing metalloenzyme. The most distinctive feature of this enzyme is its composite molecular framework, which combines lignin peroxidase's capacity to oxidize compounds with high-redox potential with manganese peroxidase's capacity to oxidize Mn2+ to Mn3+. In this study, we have extracted amino acid sequences from the Citrus sinensis source and subjected them to various computation tools to visualize the insight secondary and 3D structure, physicochemical properties, and validation of the structure which have not been studied so far to further investigate the catalytic efficiency and effectiveness of VP. The binding energies of HEME and HEME C (HEC) ligands with produced PDB (6rqf.1. A) have been also assessed, analyzed, and confirmed utilizing AutoDock. Binding energies were calculated using the AutoDock and validated by MD simulation using SCHRODINGER DESMOND. Most stable confirmation was achieved through a protein-ligand interaction study. Bio-technological use of VP in the biotransformation of β-naphthol has also been studied. The findings in the current study will have a substantial impact on proteomics, biochemistry, biotechnology, and possible uses of versatile peroxidase in the bio-remediation of different toxic organic compounds.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-023-03758-x.

Natural Melanogenesis Inhibitor, Antioxidant, and Collagen Biosynthesis Stimulator of Phytochemicals in Rice Bran and Husk Extracts from Purple Glutinous Rice (Oryza sativa L. cv. Pieisu 1 CMU) for Cosmetic Application

Oryza sativa L. cv. Pieisu 1 CMU (PES1CMU) has a high anthocyanin content in the colored bran and high phenolic content in the husk. Biologically active compounds in plants are available as dietary supplements and cosmetics. To expand the utilization of natural resources, PES1CMU will be a natural remedy for skin hyperpigmentation and aging. Cell-free tyrosinase inhibition and scavenging assays were used to screen all extracts, including PES1CMU-rice bran oil (RBO), PES1CMU-defatted rice bran (DFRB), and PES1CMU-husk (H). PES1CMU extracts were first examined in IBMX-stimulated B16 cells and H₂O₂-induced fibroblasts. The results exhibited that PES1CMU-DFRB was the most effective inhibitor of mushroom tyrosinase, intracellular melanin production (fold change of 1.11 ± 0.01), and tyrosinase activity (fold change of 1.22 ± 0.10) in IBMX-stimulated B16 cells. Particularly, PES1CMU-DFRB showed a comparable whitening effect to the standard arbutin with no significant difference (p > 0.05). Moreover, PES1CMU-DFRB and PES1CMU-H demonstrated strong scavenging activities. After accelerated cell aging caused by H₂O₂ exposure in fibroblasts, the levels of malondialdehyde production in all PES1CMU-treated fibroblasts were comparable with those of standard l-ascorbic acid (p > 0.05). Besides, PES1CMU-DFRB and PES1CMU-H treatment significantly inhibited collagen degradation against MMP-2 compared to l-ascorbic acid-treated cells (p > 0.05). PES1CMU rice-processing wastes (DFRB and H) could become potential natural sources for dermatocosmetic constituents in skin anti-aging and whitening products.

Effect-Directed, Chemical and Taxonomic Profiling of Peppermint Proprietary Varieties and Corresponding Leaf Extracts

During the development of novel, standardized peppermint extracts targeting functional applications, it is critical to adequately characterize raw material plant sources to assure quality and consistency of the end-product. This study aimed to characterize existing and proprietary, newly bred varieties of peppermint and their corresponding aqueous extract products. Taxonomy was confirmed through genetic authenticity assessment. Non-target effect-directed profiling was developed using high-performance thin-layer chromatography-multi-imaging-effect-directed assays (HPTLC-UV/Vis/FLD-EDA). Results demonstrated substantial differences in compounds associated with functional attributes, notably antioxidant potential, between the peppermint samples. Further chemical analysis by high-performance liquid chromatography-photodiode array/mass spectrometry detection (HPLC-PDA/MS) and headspace solid-phase microextraction-gas chromatography-flame ionization/MS detection (headspace SPME-GC-FID/MS) confirmed compositional differences. A broad variability in the contents of flavonoids and volatiles was observed. The peppermint samples were further screened for their antioxidant potential using the Caenorhabditis elegans model, and the results indicated concordance with observed content differences of the identified functional compounds. These results documented variability among raw materials of peppermint leaves, which can yield highly variable extract products that may result in differing effects on functional targets in vivo. Hence, product standardization via effect-directed profiles is proposed as an appropriate tool.

Quercetin 3-O-Galactoside Isolated from Limonium tetragonum Inhibits Melanogenesis by Regulating PKA/MITF Signaling and ERK Activation

Quercetin 3-O-galactoside (Q3G) is a common dietary flavanol that has been shown to possess several bioactivities, including anti-melanogenesis. However, how Q3G exerts its anti-melanogenic effect has not been studied. The current study, therefore aimed to investigate the anti-melanogenesis potential of Q3G and elucidate the underlying action mechanism in α-melanocyte-stimulating hormone (α-MSH)-induced hyperpigmentation model of B16F10 murine melanoma cells. Results showed that α-MSH stimulation significantly increased tyrosinase (TYR) and melanin production, which were significantly downregulated by Q3G treatment. The treatment with Q3G suppressed the transcriptional and protein expressions of melanogenesis-related enzymes TYR, tyrosinase related protein-1 (TRP-1), and TRP-2, along with the melanogenic transcription factor microphthalmia-associated transcription factor (MITF) in B16F10 cells. It was shown that Q3G downregulated MITF expression and suppressed its transcriptional activity by inhibiting the cAMP-dependent protein kinase A (PKA)-mediated activation of CREB and GSK3β. In addition, MAPK-regulated MITF activation signaling was also involved in the inhibition of melanin production by Q3G. The results suggest that the anti-melanogenic properties of Q3G rationalize further studies in vivo to confirm its action mechanism and consequent utilization as a cosmetic ingredient against hyperpigmentation.

Anti-Inflammatory, Antioxidative, and Nitric Oxide-Scavenging Activities of a Quercetin Nanosuspension with Polyethylene Glycol in LPS-Induced RAW 264.7 Macrophages

Quercetin (Qu) is a dietary antioxidant and a member of flavonoids in the plant polyphenol family. Qu has a high ability to scavenge reactive oxygen species (ROS) and reactive nitrogen species (RNS) molecules; hence, exhibiting beneficial effects in preventing obesity, diabetes, cancer, cardiovascular diseases, and inflammation. However, quercetin has low bioavailability due to poor water solubility, low absorption, and rapid excretion from the body. To address these issues, the usage of Qu nanosuspensions can improve physical stability, solubility, and pharmacokinetics. Therefore, we developed a Qu and polyethylene glycol nanosuspension (Qu-PEG NS) and confirmed its interaction by Fourier transform infrared analysis. Qu-PEG NS did not show cytotoxicity to HaCaT and RAW 264.7 cells. Furthermore, Qu-PEG NS effectively reduced the nitrogen oxide (NO) production in lipopolysaccharide (LPS)-induced inflammatory RAW 264.7 cells. Additionally, Qu-PEG NS effectively lowered the levels of COX-2, NF-κB p65, and IL-1β in the LPS-induced inflammatory RAW 264.7 cells. Specifically, Qu-PEG NS exhibited anti-inflammatory properties by scavenging the ROS and RNS and mediated the inhibition of NF-κB signaling pathways. In addition, Qu-PEG NS had a high antioxidant effect and antibacterial activity against Escherichia coli and Bacillus cereus. Therefore, the developed novel nanosuspension showed comparable antioxidant, anti-inflammatory, and antibacterial functions and may also improve solubility and physical stability compared to raw quercetin.