In the present study, a novel quinone-substituted piperazine compound (3) was synthesized and characterized using various spectroscopic techniques including FT-IR,1H NMR,13C NMR, UV-Vis, and MS analyses. The conformational preferences of compound (3) were investigated using the semi-empirical PM3 method, and the lowest-energy conformer was then optimized using the Density Functional Theory (DFT) at the wb97xd/6-311++G(d,p) level to determine its optimized structure. Molecular electrostatic potential (MEP) and frontier molecular orbitals (HOMO, LUMO) analyses were performed on the optimized structure using the same level of theory. Molecular docking studies revealed that compound (3) binds strongly to DNA and to Escherichia coli DNA gyrase B. Molecular dynamics (MD) simulations over 200 ns indicated that the (3)-DNA and (3)-6F86 complexes remained stable under the simulated conditions. These in silico results provide preliminary insights into the potential biological activities of compound (3), but experimental studies are needed to confirm these findings. The antibacterial and antifungal activities of (3) were evaluated using the disk diffusion method against various Gram-positive and Gram-negative bacterial strains, including Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, and Escherichia coli. The results showed that compound (3) exhibited greater antimicrobial activity than its precursor (1), particularly against Enterococcus faecalis and Micrococcus luteus. Additionally, (3) demonstrated significant antifungal activity against Aspergillus niger and Alternaria alternata.

Thymotrinan is an immunomodulating tripeptide containing the Arg-Lys-Asp sequence.In this study, the structural, vibrational, and electronic properties, as well as the bioactivity of thymotrinan, have been thoroughly examined.The conformational preferences of thymotrinan were evaluated through conformational analysis, and the lowest-energy conformer was then optimized using DFT/WB97XD/6–31 + + G(d, p) theory level.The vibrational wavenumbers of the optimized structure were calculated, and the molecular electrostatic potential (MEP) and frontier molecular orbital (HOMO, LUMO) analyses were performed. To analyze how thymotrinan interacts with the α7 nicotinic acetylcholine receptor chimera and to evaluate its potential to inhibit α-Bungarotoxin, a snake venom protein, molecular docking studies were performed between thymotrinan and target proteins, including the α7nAchR chimera in complex with α-BTx(PDB ID 4HQP), the α7nAchR chimera without the α-BTx protein(α-BTx-removed 4HQP), and α-BTx(PDB code: 1IK8).Afterwards, the thymotrinan-1IK8 complex was subjected to 200 ns of all-atom molecular dynamics (MD) simulations to demonstrate its stability.Based on the MD trajectory, the binding free energy of the complex was estimated to be -18.545 kcal/mol using the MM-PBSA method.In addition, in silico pharmacological predictions suggest that thymotrinan may exhibit anticancer activity against multiple cancer cell lines and antibacterial activity against a range of bacterial species. However, experimental validation of these findings remains required.

Thymocartin, also known as Thymopoietin II (32-35), is a tetrapeptide fragment (Arg-Lys-Asp-Val) of thymopoietin with immunomodulatory properties. In this study, thymocartin was thoroughly examined for its structural features and antibacterial, antiviral, and anticancer activities. Conformational analysis was performed to investigate its conformational preferences and better understand its biological activity. The most stable conformer identified was optimized using density functional theory (DFT) at the B3LYP/6-311++G(d,p) level. The vibrational wavenumbers of the optimized structure were calculated and compared with experimental data to evaluate the accuracy of the computational structure. The potential of thymocartin as an anticancer agent was explored through molecular docking simulations with E. coli DNA Gyrase B (PDB ID: 6F86) and the epidermal growth factor receptor (EGFR; PDB ID: 4HJO). Following molecular docking, 200 ns all-atom molecular dynamics (MD) simulations were conducted on the top-scoring ligand-receptor complexes involving 4HJO and 6F86, providing further insight into ligand-receptor interactions. Overall, thymocartin showed diverse biological activities, especially antibacterial and anticancer effects.

Lipopeptides are natural molecules with amphiphilic properties that exhibit various biological activities due to their lipid and peptide components. In this study, the structural, electronic, and vibrational properties of C16-Glu-Gln-Arg-Pro-Arg (C16-EQRPR), a newly synthesized lipopentapeptide formed by attaching palmitic acid to the N-terminus of the pentapeptide, were analyzed. Additionally, its antiviral and anticancer properties were evaluated through molecular docking studies. First, conformational analysis of C16-EQRPR was performed using the MMFF molecular mechanics method, and the lowest-energy conformer obtained was then optimized using DFT/wb97xd/6-31G(d,p) level of theory. The geometric parameters of the optimized structure were reported. Vibrational frequencies were calculated using the same level of theory and compared with experimental results. Complete vibrational assignments were made based on the potential energy distribution (PED) of the vibrational modes. Molecular electrostatic potential (MEP) analysis was performed for the optimized structure. The anticancer and antiviral effects of the lipopeptide were computationally assessed through molecular docking simulations of C16-EQRPR binding to the active sites of various targets, including B-DNA, ACE2, integrins (α5β3, αIIBβ3, and α5β1), human serum albumin, EGFR, FYN, and apo, as well as the holo forms of SARS-CoV-2 MPro and SARS-CoV-2 spike glycoprotein. Following molecular docking calculations, the interaction of lipopentapeptide with integrin α5β1(PDB ID: 4WK0) was analyzed in detail using molecular dynamics simulations. This study aims to characterize the molecular and biological features of the C16-EQRPR lipopeptide, highlighting its potential as both an anticancer and antiviral agent. However, experimental validation of these findings remains required.

Human serum albumin (HSA) is a key transport protein whose ability to bind multiple endogenous and exogenous ligands is governed by site heterogeneity and long-range conformational coupling; however, the mechanisms underlying ligand redistribution among binding sites, particularly in nanoparticulate HSA, remain poorly understood. To address this, we systematically examined the binding of ANS, DAUDA, palmitic acid (PA), and the anticancer lipopeptide PA-EQRPR to monomeric HSA (mHSA) and HSA nanoparticles (HSA-NPs) using steady-state and time-resolved fluorescence spectroscopy complemented by molecular modeling. In mHSA, three spectroscopically distinct binding species were resolved, with fluorescence lifetimes of ∼22.7, 14.5, and 1.6 ns and dissociation constants of 0.33, 9.0, and 3.3 μM, revealing multiple binding environments with distinct affinities and dynamics. Competitive binding experiments demonstrated cooperative PA binding and showed that PA-EQRPR not only displaces ANS or DAUDA but also promotes their redistribution to alternative, more hydrophobic sites, consistent with ligand-induced allosteric site-site communication. Lifetime-resolved analysis of DAUDA further revealed that PA stabilizes long-lived, high-affinity binding states, while PA-EQRPR shifts ligand populations toward deeper hydrophobic environments, enhancing fluorescence. HSA-NPs prepared using ethanol or acetone exhibited markedly different binding behaviors from mHSA, highlighting the impact of protein organization on ligand accessibility. Ethanol-induced HSA-NPs favored long-lifetime, hydrophobic binding species, whereas acetone-induced particles showed reduced site heterogeneity. Docking and molecular dynamics simulations revealed ligand-driven conformational rearrangements that reshape HSA's hydrophobicity landscape. Together, these findings introduce an allosteric population-shift framework that rationalizes multisite ligand binding and redistribution in both monomeric and nanoparticulate HSA.

The melanoma pathophysiology is considerably complex. Wnt signaling via the β-catenin/transcription factor 7-like 2 (TCF4)/Lymphoid enhancer-binding factor 1 (LEF1) complex, the microphthalmia-associated transcription factor (MITF), tyrosinase-related protein-2 (TRP-2), tyrosinase (Tyr) and cyclin-dependent kinase 2 (Cdk2) are reported to activate the transcriptional gene expression associated with pigmentation and the differentiation and proliferation of melanocytes and malignant melanoma cells. Cinobufagin is a leading active ingredient in Traditional Chinese Medicine, and has been approved in China as a chemotherapeutic agent for the treatment of liver and prostate cancer. The primary aim of the present study is to evaluate the effects of cinobufagin and paclitaxel on melanoma cells, both individually and in combination, in the G361 melanoma cell line. Within the scope of the study, IC50 doses were determined based on an MTT analysis, Caspase-3 measurements were analyzed using the ELISA method and mRNA expression levels were analyzed using the RT PCR method. Cinobufagin used in combination with paclitaxel was found to increase Caspase-3 levels more than when cinobufagin was used alone, and it was further determined that cinobufagin treatment decreased the expression levels of the β-catenin, C-myc and Cyclin D1 genes, while paclitaxel and cinobufagin used in combination were found to increase all mRNA expression levels (Bax, Caspase-3, Bcl2, β-catenin, C-myc, Wnt and Cyclin D1). Cinobufagin can be considered a promising natural pharmaceutical agent for the targeted treatment of cancers with high levels of LEF1.

Two new anthraquinone derivatives: 1-(4-ethylpiperazin-1-yl)-5-chloroanthracene-9,10-dione and 1-(4-methylpiperidine-1-yl)-5-chloroanhtrecene-9,10-dione were synthesized in the laboratory and their structures were confirmed by Fourier transform-infrared and nuclear magnetic resonance techniques. The optimal molecular geometry was determined using a 6-311+G(d,p) basis set and the Density Functional Theory, B3LYP approach. The presence of charge transfer within the molecule was demonstrated by the energy gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO). These new anthraquinone derivatives exhibited antibacterial activity against both Gram-positive and Gram-negative bacteria. The highest antimicrobial effect was observed against Gram-positive bacteria, especially Bacillus cereus and Staphylococcus aureus. The antibacterial properties of these new anthraquinone derivatives were also demonstrated by molecular docking simulations using Escherichia coli DNA gyrase B (PDB ID: 6F86). Moreover, molecular dynamics (MD) simulations conducted over a 100 ns period verified that the 1-(4-ethylpiperazin-1-yl)-5-chloroanthracene-9,10-dione-6F86 and 1-(4-methylpiperidine-1-yl)-5-chloroanhtrecene-9,10-dione-6F86 complexes were stable. According to a combination of experimental, computational, and biological research, compounds are promising antibacterial agents that might be developed further.

In this study, the conformational behavior of two dietary dipeptides, H-Trp-Arg-OH (WR) and H‑Trp-Glu-OH (WE), which are agonists of peroxisome proliferator-activated receptor alpha (PPAR-α), was examined using molecular mechanics and molecular dynamics methods. Subsequently, the most stable conformer of each dipeptide, WR and WE, was docked into the PPAR-α ligand-binding domain (PDB ID: 6KB0), DNA (PDB ID: 1BNA), and Human Serum Albumin (HSA; PDB ID: 1AO6) to explore their interaction mechanisms, metabolic roles, and biological activities. The conformational behavior of these dipeptides and the dynamics of their side chains were studied with molecular mechanics, which identified a set of energetically favored conformers. Molecular dynamics studies on the conformational stability of the dipeptides revealed a limited number of stable conformers that tend to adopt unfolded structures. The molecular electrostatic potential (MEP) surface and dipole moment values of the most stable zwitterionic conformation of both dipeptides were calculated at the DFT/B3LYP/6-31++G(d,p) level of theory. Docking studies of WR and WE with DNA (1BNA) showed binding energies of –8.27 and –7.60 kcal/mol, respectively; docking with HSA revealed binding energies of –7.37 and –8.10 kcal/mol, respectively; and docking with 6KB0 showed binding energies of –5.98 and –6.20 kcal/mol, respectively. These docking results clarified the interaction mechanisms between each dipeptide and receptor. Furthermore, the top-scoring WR-6KB0 complex from the docking studies was subjected to 100 ns of all-atom molecular dynamics (MD) simulations to examine the stability of the complex and ligand-receptor interactions in greater detail.

ABSTRACT Herpes simplex virus Type 1 (HSV‐1) is a prevalent infectious agent globally, often causing oral infections like gingivostomatitis. The ICP0 protein of HSV‐1 exacerbates infection severity by inhibiting antiviral responses. Our study explored how combinations of CAPE (caffeic acid phenethyl ester) and acyclovir influenced immune responses in gingival cells treated with ICP0 We applied ICP0 protein, CAPE, acyclovir, and their combinations to HGF‐1 cells for 24 h. IC50 dose amounts were determined using the MTT cell viability test, gene expressions were assessed by RT‐PCR, and protein levels were gauged by the ELISA method. No statistically significant changes were noted between the ICP0 applied groups and the control groups (p > 0.05). However, significant increases were observed in the IFN‐β (p < 0.0001), IFN‐γ (p < 0.0001), IRF3 (p < 0.0001), β‐catenin (p < 0.0001), WNT‐1 (p < 0.0001). protein levels of the ICP0 + CAPE applied groups. The increases in all groups administered ICP0 + acyclovir surpassed those administered ICP0 + CAPE (p < 0.0001). The combination of CAPE and acyclovir could potentially reduce both the adverse effects caused by the ICP0 protein and the undesirable side effects that may be caused by the acyclovir used in the treatment. This combination could serve as a potential therapy in the treatment of HSV‐1.

In this study, we present detailed results on the molecular structure, vibrational frequencies, and bioactivity of the neutral L-Glu-L-Gln-L-Arg-L-Pro-L-Arg (EQRPR) pentapeptide, derived from rice bran, which exhibits anti-cancer, anti-Alzheimer's, and anti-obesity properties. Theoretical conformational analysis was performed to evaluate the conformational preferences of the pentapeptide. The most stable conformer was then optimized at the DFT/b3lyp/6-31G(d,p), DFT/b3lyp/6-31 + G(d,p), and DFT/wb97xd/6-31++G(d,p) levels of theory. The experimental FTIR and Raman spectra were compared with the theoretically predicted vibrational spectra at these levels. As the DFT/wb97xd/6-31++G(d,p) results showed the closest agreement with the experimental data, all subsequent calculations were performed using this level of theory. The molecular electrostatic potential (MEP) and frontier molecular orbitals were calculated using the optimized pentapeptide structure to evaluate its chemical reactivity. To investigate its potential biological activity as an anticancer and antiviral agent, molecular docking studies were performed against 1BNA, 4HJO, 1JV2, 3ZDX, 4WK0, 6 M03, 6 LU7, and 6VXX targets. Among these, the EQRPR pentapeptide exhibited the strongest binding affinity toward alpha 5 beta 1 integrin (4WK0; triangle G = -9.3 kcal/mol). Furthermore, following the docking calculations, the best conformation of the EQRPR-alpha 5 beta 1 integrin complex was subjected to 200 ns of all-atom molecular dynamics simulations. The MD results indicate the stability of the EQRPR-4WK0 complex, and the binding free energy was determined from the simulation results using the Molecular Mechanics/Poisson-Boltzmann Surface Area (MM-PBSA) method as -72.9895 kcal/mol. Overall, these results suggest that the neutral EQRPR pentapeptide possesses broad therapeutic potential and may serve as a promising candidate for the development of antiviral and anticancer agents.

Cancer is still a deadly disease today. The currently employed conventional methods and therapies for cancer treatment are followed by side effects. However, anticancer peptides that can inhibit tumor cell proliferation and migration, or suppress the formation of tumor blood vessels, are less likely to cause drug resistance and have fewer side effects. In this study, the interactions of Glu-Glu-Arg (EER), Glu-Pro-Arg (EPR), and Pro-Arg-Pro (PRP) tripeptides, which have anticancer properties, with human serum albumin (HSA) were evaluated by molecular docking simulations. It was shown that EER, EPR, and PRP tripeptides bind to HSA with favorable binding energies. The PRP tripeptide was the most stable in the HSA receptor among the others, with a binding energy of −8.06 kcal/mol. It was followed by the EPR tripeptide with a binding energy of −7.126 kcal/mol and the EER tripeptide with a binding energy of −6.549 kcal/mol. Human serum albumin is found to be a viable option for the delivery of these tripeptides to cancer cells.

This study determined the IC0 and IC50 doses of boric acid in the MCF-7 cell line, the extent to which boric acid inhibits proliferation at low doses, and the extent to which it affects gene expression in apoptosis. Total antioxidant and oxidant status, the effect on DNA damage, and genotoxicity were determined. The mRNA expression levels of Bcl-2, p53, TRAIL2, and Bax genes related to apoptosis and proliferation, were analysed by RT-PCR. Estrogen receptor alpha positive (ER alpha+) and Caspase 3+ cells were analysed by immunocytochemical methods. The obtained data showed that the IC0 and IC50 doses of boric acid increased oxidative stress, with statistical significance (p < 0.05). The IC50 dose also had genotoxic effects. It was determined that the IC0 dose suppressed Bcl-2, p53, and TRAIL2, and the IC50 dose suppressed Bax. It was found that the ER alpha+ and Caspase 3+ cell numbers in all groups were higher than in the control. This shows that all applied doses increased the activation of Caspase 3, an apoptotic marker. It can be said that boric acid is also anticarcinogenic at high doses.

Melanoma is an aggressive malignancy characterized by high metastatic potential and resistance to conventional therapies. Emerging evidence suggests that purinergic P2X receptors, particularly P2X7, play critical roles in regulating tumor cell proliferation, apoptosis, and invasion. However, the transcriptional regulation of P2X receptor subtypes in response to therapeutic compounds remains incompletely characterized. This study aimed to investigate the transcriptional modulation of all seven P2X receptor subtypes (P2XR1–7) in G361 melanoma cells following exposure to selected phenolic compounds and chemotherapeutic agents. Cell viability was evaluated by MTT assay, and half-maximal inhibitory concentrations (IC₅₀) were determined using non-linear regression analysis in GraphPad Prism software. Chemotherapeutic agents, including paclitaxel and sunitinib, exhibited strong cytotoxic effects under the experimental conditions employed, whereas phenolic compounds (quercetin, retinoic acid, and resveratrol) demonstrated moderate anti-proliferative activity. Quantitative real-time PCR analyses revealed compound-specific transcriptional response patterns. Quercetin induced upregulation across multiple P2X receptor subtypes, retinoic acid exhibited a partially suppressive profile, and resveratrol showed selective downregulation. In contrast, chemotherapeutic agents generally induced mRNA upregulation, particularly in P2XR4, P2XR5, and P2XR7 subtypes. These findings demonstrate that P2X receptor genes are differentially modulated at the transcriptional level by natural and synthetic compounds. The present work provides a transcriptional framework identifying subtype-specific response patterns and nominates candidate P2X receptors for future protein-level and functional validation studies in melanoma.

Objective: The antineoplastic agent Pazopanib is effective for treating renal cell cancer and soft tissue sarcoma. The aim of this study was to elucidate the anticancer mechanism of Pazopanib by exploring its molecular interactions with vascular endothelial growth factor receptors (VEGFRs). For this purpose, the most stable structure was determined, and molecular docking and molecular dynamics calculations of Pazopanib with VEGFR1 and VEGFR2 receptors were performed. Materials and Methods: Conformational analysis of Pazopanib was performed using VegaZZ software. Pazopanib was docked to the active sites of the VEGFR1 and VEGR2 receptors (PDB IDs: 3HNG; 3VHE) using Autodock Vina software. The molecular dynamics (MD) simulations were carried out using the YASARA v22.9.24 program with the AMBER14 force field. The anticancer, antibacterial, antifungal, and antiviral activities of the compounds were predicted using PaccMann, AntiBac-Pred, AntiFun-Pred, and AntiVir-Pred. Results: The molecular docking analysis of the Pazopanib molecule with the VEGFR1 and VEGFR2 receptors revealed a strong binding affinity of the investigated molecule towards the targets. The MD simulations, performed for Pazopanib-VEGFR1 and Pazopanib-VEGFR2 complexes showed that each docking complex and intermolecular interactions were stable throughout the simulations. Conclusion: Molecular docking simulations revealed a strong binding affinity of Pazopanib towards VEGFR1 (-8.6 kcal/mol) and VEGFR2 (-9.9 kcal/mol), indicating its efficacy in cancer treatment. During the 40-ns MD simulation of the Pazopanib-3hng and Pazopanib-3vhe complexes, we validated the stability of Pazopanib in the active sites of the receptors. The predicted anticancer, antibacterial, antifungal, and antiviral activities of Pazopanib revealed its versatile bioactivity.

Molecular docking is one of the most widely used techniques for simulating molecular interactions between molecules and forecasting the mode of binding and affinities between them. Due to the presence of structure-function relationship, in this study firstly, the molecular structures of the cellulose I(alpha) and I(beta) molecules were optimized and their most stable structures were determined by density functional theory (DFT) using B3LYP method with 6-31G(d,p) basis set. The vibrational wavenumbers of 1-ring, 2-ring, 3-ring, and 4-ring structures of cellulose I(alpha) and I(beta) were calculated using the same level of theory. Reliable vibrational assignments were made based on potential energy distribution (PED %) of the vibrational modes. The energy gap (Eg = ELUMO-EHOMO) of the cellulose I alpha and cellulose Ip was found to be 8.286 eV and 7.965 eV, respectively. To identify the molecular interactions between cellulose I alpha and Ip ligands and the cellulase enzymes, molecular docking studies were performed. The molecular docking results revealed the strong interaction of the cellulose I alpha and Ip with Endoglucanase enzyme (-6.4 and-6.3 kcal/mol, respectively), enzyme beta-glucosidase (-5.3 and-5.2 kcal/mol, respectively), and Exoglucanase enzyme (-6.1 and-6.2 kcal/mol, respectively).

Bleomycin (BLM) is the first-line clinical antibiotic used in the treatment of cancer. It inhibits DNA metabolism and is used in conjunction with other anticancer medications to treat various kinds of malignant tumors. This work focuses on examining more fully the bioactivity of BLM as both anticancer and antibacterial agents. Due to the structure-function relationship, the conformational study of the molecule was carried out first, and its potential conformations were identified. Afterwards, using the energy minimization feature of the YASARA structure program, the obtained lowest energy conformation of the molecule and the receptor taken from the protein databank (ligand-free) were optimized. BLM was subjected to molecular docking tests with two antibiotic-binding proteins (PDB IDs: 1ewj and 2zw7) to determine its action mechanism as a TN5 transposon inhibitor. Moreover, its binding affinities towards thymidylate kinase (TMK) (PDB ID: 4qgg) Escherichia coli DNA gyrase B (PDB ID: 6f86) were also evaluated to reveal its antibacterial potential. Additionally, ligand-receptor interactions were assessed via molecular dynamics (MD) process to confirm the stability of BLM docked into antibiotic binding protein (1ewj), TMK (4qgg) and E. coli DNA gyrase B (6f86) within 500 ns (for 1ewj and 6f86) or 200 ns of time (for 4qgg). Molecular mechanics/Poisson-Boltzmann Surface Area methods (MM/PBSA) were used to compute the binding energies through MD simulations. Dynamics cross correlation matrices (DCCM) analysis and principal component analysis (PCA) on the MD data were performed. Results have cleared the mechanism of action of BLM having anticancer and antibacterial properties.

To gain deeper insights into the biological activity of thymopentin, its structural, anticancer, antiviral and antimicrobial properties were systematically investigated. Conformational preferences of thymopentin were investigated through conformational analysis and the lowest energy conformation was optimized using density functional theory (DFT) method, Becke three Lee-Yang-Parr (B3LYP) functional and 6-31G(d,p) basis set. Vibrational wavenumbers of the optimized structure were computed and compared with the experimental results. To elucidate the potential of thymopentin as anti-COVID-19 and anticancer agents, molecular docking simulations were performed. Thymopentin was docked into DNA (PDB ID: 1BNA), SARS-CoV-2 main protease (PDB ID: 6M03) and EGFR receptor complex (PDB ID: 4HJO). Additionally, following molecular docking analyses, top-scoring ligand-receptor complexes of thymopentin with SARS-CoV-2 enzyme (6M03) and EGFR (4HJO) were subjected to 50 ns all-atom molecular dynamics (MD) simulations to examine the ligand-receptor interactions in greater detail. Moreover, the antimicrobial potency of thymopentin against the most prevailing human pathogenic microorganisms was also investigated. The strongest antibacterial activity was observed against "Listeria monocytogenes", a pathogenic bacterium capable of causing listeriosis, a serious infection that can potentially lead to death. This study revealed the anticancer, anti-Covid 19 and antimicrobial activities of the thymopentin molecule, demonstrating its multifunctional bioactivity.

The development and progression of osteoarthritis (OA) are believed to involve inflammation. This study aimed to investigate the effects of applying therapeutic ultrasound (US) to human osteoarthritic chondrocytes in continuous and pulsed modes on cell proliferation and proinflammatory cytokine levels. Human osteoarthritic chondrocytes (HC-OA 402OA-05a) were proliferated in appropriate media and then seeded into culture plates. The plates were grouped and exposed to underwater continuous, pulsed and control US at 0.1 W/cm2 and 1 MHz for 10 min daily for 10 days. Cell viability/proliferation was assessed using the MTT assay, total protein was measured by ELISA and cytokine levels per protein were determined. Cells were photographed using microscopic analysis. Both continuous and pulsed US groups showed a significant increase in viability compared to the control group. No significant difference was found between the continuous and pulsed US groups for IL-1β, TNF-α and IL-6 levels. Both groups showed significant cytokine reduction compared to the control group. For IL-17 and IL-32 levels, both US groups had reduced cytokine levels compared to the control group, but the results were not significant. Underwater US at 0.1 W/cm2 and 1 MHz stimulated cell proliferation and reduced proinflammatory cytokine levels in osteoarthritic chondrocyte cell cultures. This study extensively focused on proinflammatory IL levels, and the meaningful results may inspire future in vivo/in vitro studies. While adapting in vitro data to in vivo conditions poses challenges, our results could guide future in vivo studies and clinical applications.

Teething gels are used to treat various oral mucosal conditions and inflammation. The effect of teething gels on cytokines involved in the inflammatory process is unknown. This study aimed to assess the influence of teething gels on the levels of inflammatory cytokines in human gingival fibroblasts using an in vitro assay. In this study, MTT (3-[4,5-methylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) test was used to calculate the values that provide 50% survival of the cells with different teething gels applied to human gingival fibroblast cells. Using Enzyme-Linked Immunosorbent Assay kits, Interleukin-1β, Interleukin-6, Interleukin-8, Tumor necrosis factor-α, and Interleukin-10 cytokine levels were measured in the control group and in fibroblast cells treated with each teething gel. The statistical analysis of the data was done with SPSS program. All of the teething gels caused various levels of suppression of the cytokines governing the inflammatory process (p < 0.05). Interleukin-1β levels were significantly lower in the hyaluronic acid group than in the lidocaine group (p < 0.05). Interleukin-8 levels were significantly lower in all teething gel groups compared with the control group (p < 0.0001). In conclusion, all of the teething gels in this study were able to suppress the cytokines that regulate the inflammatory process. Considering the cytotoxic side effects of other teething gels, it is concluded that hyaluronic acid-based teething gels have a safe and tolerable profile in the suppression of cytokines that manage the inflammation process in symptom-directed treatments. Graphical abstract

SARS-CoV-2 initiates infection by binding its surface spike glycoprotein to the ACE2 receptor on the human cell surface, facilitating the entry of its genetic material into the human cell. Due to the pivotal role of the spike protein in this infection mechanism, in this study the versatility of the bioactivity of the doxylamine molecule was investigated, and by theoretical molecular modeling studies its potential of blocking the entry of the spike protein into human cells was revealed. In the initial phase of this investigation, conformational analysis of doxylamine was executed employing the PM3 method, yielding six stable conformations. Subsequently, the lowest energy conformation obtained was subjected to optimization at the DFT/B3LYP/6-31++G(d,p) level of theory. Vibrational wavenumbers, highest occupied and lowest unoccupied molecular orbitals, and molecular electrostatic potential for the most stable conformer of doxylamine were computed using the DFT/B3LYP/6-31++G(d,p) level of theory. For docking studies firstly, the optimization by energy minimization feature of the YASARA structure program was employed to both ligand and the ligand-free receptor obtained from the protein databank. Molecular docking simulations were adeptly employed to identify potential compounds with doxylamine anticipated to demonstrate inhibitory activity against the spike protein of SARS-CoV-2. Molecular docking study of doxylamine was conducted with spike receptor-binding domain (RBD) of SARS-CoV-2 (PDB ID: 6M0J). Furthermore, ligand-receptor interactions were scrutinized through a molecular dynamics (MD) simulation lasting 125 ns to verify the stability of doxylamine within the ACE2 binding site.