Binding of Foeniculum vulgare essential oil and its major compounds to double-stranded DNA: In silico and in vitro studies

In vitro Genotoxicity and In silico Docking Analyses of the Essential Oils of Thuja orientalis

Two main objectives were pursued to assess the reliability of Thuja orientalis essential oils (TOEO). The first objective was to extract TOEO, analyze them by GC-MS, and determine their in vitro genotoxicity against selected plants using the RAPD-PCR method. The second objective was to evaluate the in-silico toxicity of TOEO. The binding sites and energies of each content was calculated against B-DNA. In-silico analyses were performed using a simulation program, AutoDock Vina, and Toxicity Estimation Software Tools. 3-carene, cedrol, and 2-pinene were identified as the predominant components. In vitro studies showed that the TOEO had a more significant impact on reducing genomic stability in wheat compared to the amaranth. The lowest stability was determined as 39.78 % in wheat and 53.58 % in amaranth. Cedrol (-5,7 kcal/mol) and selinene (-5,6 kcal/mol) exhibited the highest binding affinity. The toxicity test indicated that components other than cyclohexene may have toxic effects, none of them were predicted to be mutagenic, and LD50 (mol/kg) values could vary between 1.33 and 1.55.

Peptidic Compound as DNA Binding Agent: In Silico Fragment-based Design, Machine Learning, Molecular Modeling, Synthesis, and DNA Binding Evaluation

BACKGROUND

Cancer remains a global burden, with increasing mortality rates. Current cancer treatments involve controlling the transcription of malignant DNA genes, either directly or indirectly. DNA exhibits various structural forms, including the G-quadruplex (G4), a secondary structure in guanine-rich regions. G4 plays a crucial role in cellular processes by regulating gene expression and telomerase function. Researchers have recently identified G4-stabilizing binding agents as promising anti-cancer compounds. Additionally, peptides have emerged as effective anticancer pharmaceuticals due to their ability to form multiple hydrogen bonds, electrostatic interactions, and van der Waals forces. These properties enable peptides to bind to specific areas of DNA chains selectively. However, despite these advancements, designing G4-binding peptides remains challenging due to a lack of comprehensive information.

OBJECTIVE

In our present study, we employed an in silico fragment-based approach to design G4- binding peptides. This innovative method combines machine learning classification, molecular docking, and dynamics simulation.

METHODS

AutoDock Vina and Gromacs performed molecular docking and MD simulation, respectively. The machine learning algorithm was implemented by Scikit-learn. Peptide synthesis was performed using the SPPS method. The DNA binding affinity was measured by applying spectrophotometric titration.

RESULTS

As a result of this approach, we identified a high-scoring peptide (p10; sequence: YWRWR). The association constant (Ka) between p10 and the ctDNA double helix chain was 4.45 × 105 M-1. Molecular modeling studies revealed that p10 could form a stable complex with the G4 surface.

CONCLUSION

The obtained Ka value of 4.45 × 105 M-1 indicates favorable interactions. Our findings highlight the role of machine learning and molecular modeling approaches in designing new G4-binding peptides. Further research in this field could lead to targeted treatments that exploit the unique properties of G4 structures.

Ferulago bernardii as a New Source of α-Pinene Binds to ctDNA: In Silico and in Vitro Studies

Ferulago bernardii Tomk & M. Pimen belongs to Apiaceae family. Various species of the Ferulago genus have antioxidant, anticholinesterase, cytotoxic, and antiproliferative effects. In this study, the essential oil of F. bernardii was extracted using the Clevenger apparatus. The essential oil compounds were identified using GC-MS/FID. The interaction between the essential oil and DNA strands was evaluated through spectrophotometric titration. The molecular mechanism of the interaction between the main components of the essential oil and different DNA strands was assessed using molecular dynamics simulation. Based on the results, 92.03±1.20 % of the essential oil consisted of α-pinene. Therefore, the essential oil could serve as a suitable source of α-pinene. α-pinene is a monoterpene hydrocarbon that has various effects, including anti-inflammatory, antioxidant, antimicrobial, and antitumor properties. The binding constant of the essential oil to DNA strands (Ka ) was determined to be 5.40±0.47×10-3  M-1 . Molecular dynamics simulation demonstrated that α-pinene could interact with AT and CG rich DNA strands and indirectly stabilize G-Quadruplex. Given the different applications for α-pinene and its high percentage in the essential oil, it is suggested that researchers pay more attention to F. bernardii in the pharmaceutical, cosmetic, and food industries.

Design, synthesis, molecular modeling and DNA-binding studies of new barbituric acid derivatives

Cancer disease is developing all over the world mainly in developing countries. We should learn more about DNA–ligand interactions to design new drugs that target biological activities like transcription, replication and translation of particular genes. To understand the mechanism of action and design-specific DNA binders, the evaluation of DNA–ligand interactions is critical. Novel barbituric acid derivatives based on (benzyloxy)benzaldehydes were synthesized and evaluated as DNA-binding agents. Among products, molecular docking studies revealed that 4j and 4m have the best interactions with the ctDNA via the minor groove binding. These results were approved by the quantum mechanics calculations. The interaction profiles of the selected compound (4j and 4m) with DNA were evaluated by UV–Visible titration. UV–Visible titration data confirm this interaction. According to the molecular modeling results, the Structure–Activity relationships for all synthesized barbituric acid derivatives were proposed. It was observed that N,N-dimethyl barbituric acid/4-hydroxybenzaldehyde derivatives have better DNA interactions than barbituric acid/vanillin and barbituric acid/3-hydroxybenzaldehyde derivatives.