Ligand substituent effect on the cytotoxicity activity of two new copper(ii) complexes bearing 8-hydroxyquinoline derivatives: validated by MTT assay and apoptosis in MCF-7 cancer cell line (human breast cancer)

CogniFiber: Harnessing Biocompatible and Biodegradable 1D Collagen Nanofibers for Sustainable Nonvolatile Memory and Synaptic Learning Applications

Here, resistive switching (RS) devices are fabricated using naturally abundant, nontoxic, biocompatible, and biodegradable biomaterials. For this purpose, 1D chitosan nanofibers (NFs), collagen NFs, and chitosan-collagen NFs are synthesized by using an electrospinning technique. Among different NFs, the collagen-NFs-based device shows promising RS characteristics. In particular, the optimized Ag/collagen NFs/fluorine-doped tin oxide RS device shows a voltage-tunable analog memory behavior and good nonvolatile memory properties. Moreover, it can also mimic various biological synaptic learning properties and can be used for pattern classification applications with the help of the spiking neural network. The time series analysis technique is employed to model and predict the switching variations of the RS device. Moreover, the collagen NFs have shown good cytotoxicity and anticancer properties, suggesting excellent biocompatibility as a switching layer. The biocompatibility of collagen NFs is explored with the help of NRK-52E (Normal Rat Kidney cell line) and MCF-7 (Michigan Cancer Foundation-7 cancer cell line). Additionally, the biodegradability of the device is evaluated through a physical transient test. This work provides a vital step toward developing a biocompatible and biodegradable switching material for sustainable nonvolatile memory and neuromorphic computing applications.

Suppression of human lysozyme aggregation by a novel copper-based complex of 3,4-dimethoxycinnamic acid

In this work, a new Cu(II)-based complex as a chemotherapeutic drug agent, formulated as[Cu(DCA)4(H2O)2]⋅4H2O⋅4MeOH, (DCA = 3,4-dimethoxycinnamic acid), namely 1 was successfully synthesized utilizing DCA as a ligand to arrest fibrillation in Human lysozyme. The 1 was thoroughly characterized by single crystal X-ray diffraction (SC-XRD), spectroscopic (UV-Vis and FTIR) techniques, PXRD, and TGA analysis. Its crystal structure reveals a paddle wheel network around central copper metal ions. The Cu(II) metal ions exhibit a distorted square pyramidal configuration. The fluorescence titration studies showed moderate binding interaction of 1 with HuL with Ka of 6.3x105 M-1 at pH-2, 25 °C due to its interaction withAsp53, Tyr63, Val110, and Ala111 as shown by docking and simulation studies. 1suppresses the HuL fibrillation in a concentration-dependent manner, as demonstrated by ThT assay. At 200 µM concentration, it leads to the formation of smaller species of the protein in comparison to the control sample, as suggested by Light Scattering studies. The species formed are less hydrophobic and retain their native α-helix structure compared to the control samples, which are hydrophobic and form β-sheet rich amyloids as shown by ANS hydrophobicity assay and CD spectroscopy, respectively. Furthermore, morphological analysis of the species by AFM has demonstrated that, unlike mature amyloid fibrils in the control sample, HuL forms small-size aggregates in the presence of 1 under similar fibrillation conditions. It can be concluded that 1 effectively suppresses HuL fibrillation due to moderate binding to the protein.Communicated by Ramaswamy H. Sarma.

Synthesis, Structure-Activity Relationship, and Mechanism of a Series of Diarylhydrazide Compounds as Potential Antifungal Agents

A series of simple diarylhydrazide derivatives (45 examples) were well-designed, prepared, and screened for their antifungal activities both in vitro and in vivo. Bioassay results suggested that all designed compounds had significant activity against Alternaria brassicae (EC₅₀ = 0.30-8.35 μg/mL). Among of them, 2c, as the highest activity compound, could effectively inhibit the growth of plant pathogens Pyricularia oryza, Fusarium solani, Alternaria solani, Alternaria brassicae, and Alternaria alternate and was more potent than carbendazim and thiabendazole. 2c showed almost 100% protection at 200 μg/mL in vivo activity against A. solani in tomato. Moreover, 2c did not affect the germination of cowpea seed and the growth of normal human hepatocytes. The preliminary mechanistic exploration documented that 2c could result in the abnormal morphology and irregular structure of the cell membrane, destroy the function of mitochondria, increase the reactive oxygen species, and inhibit the proliferation of hypha cell. The above results manifested that target compound 2c could be a potential fungicidal candidate against phytopathogenic diseases for its excellent fungicidal activities.

Design, synthesis, cytotoxic activities, and molecular docking of chalcone hybrids bearing 8-hydroxyquinoline moiety with dual tubulin/EGFR kinase inhibition

The present study established thirteen novel 8-hydroxyquinoline/chalcone hybrids3a-mof hopeful anticancer activity. According to NCI screening and MTT assay results, compounds3d-3f, 3i,3k,and3ldisplayed potent growth inhibition on HCT116 and MCF7 cells compared to Staurosporine. Among these compounds,3eand3fshowed outstanding superior activity against HCT116 and MCF7 cells and better safety toward normal WI-38 cells than Staurosporine. The enzymatic assay revealed that3e,3d, and3ihad goodtubulin polymerization inhibition (IC₅₀ = 5.3, 8.6, and 8.05 µM, respectively) compared to the reference Combretastatin A4 (IC₅₀ = 2.15 µM). Moreover,3e,3l, and3fexhibited EGFR inhibition (IC₅₀ = 0.097, 0.154, and 0.334 µM, respectively) compared to Erlotinib (IC₅₀ = 0.056 µM). Compounds3eand3fwere investigated for their effects on the cell cycle, apoptosis induction, andwnt1/β-cateningene suppression. The apoptosis markers Bax, Bcl2, Casp3, Casp9, PARP1, and β-actin were detected by Western blot. In-silico molecular docking, physicochemical, and pharmacokinetic studies were implemented for the validation of dual mechanisms and other bioavailability standards. Hence, Compounds3eand3fare promising antiproliferative leads with tubulin polymerization and EGFR kinase inhibition.

Structural, Theoretical Investigations, Hirshfeld Surface Analysis, and Cytotoxicity Profile of a Neocuproine-Co(II)-Based Discrete Homodinuclear Complex

In this work, we aimed to synthesize a new cobalt(II) complex, namely [Co₂(μ-HIPA)(NC)₂(H₂O)₃(NO₃)]·(NO₃)(C₂H₅OH)(1) (where H₃IPA = 5-hydroxy isophthalic acid and NC = 2,9-dimethyl-1,10-phenanthroline or neocuproine), as a promising chemotherapeutic agent. The diffraction (single crystal-XRD and powder-XRD), spectroscopic (FTIR and UV-visible), molar conductance, and thermal techniques were used to characterize complex 1. Single-crystal X-ray diffraction analysis reveals that Co(II) exists in an octahedral geometry, with the ligation of four oxygen atoms, and two nitrogen atoms. Topological analysis of complex 1 reveals 2,6C6 topological type as an underlying net. The plausible intermolecular interactions within complex 1 that control the crystal packing were analyzed by Hirshfeld surface analysis. In vitro cytotoxicity of complex 1 was evaluated against acute myeloid leukemia (THP-1), colorectal (SW480), and prostate (PC-3) cancer cell lines by utilizing an MTT assay. The result shows that complex 1 can inhibit the growth of cancer cells (THP-1, SW480, and PC-3) at lower inhibitory concentration (IC₅₀) values of > 100, 43.6, and 95.1 µM respectively. The morphological changes induced by complex 1 on THP-1 and SW480 cancer cell lines were carried out with acridine orange/ethidium bromide staining methods. Additionally, comprehensive molecular docking studies were performed to understand the potential binding interactions of complex 1 with different bio-macromolecules.

Promising anticancer agents based on 8-hydroxyquinoline hydrazone copper(II) complexes

We report the synthesis and characterization of a group of benzoylhydrazones (Lⁿ) derived from 2-carbaldehyde-8-hydroxyquinoline and benzylhydrazides containing distinct para substituents (R = H, Cl, F, CH₃, OCH₃, OH and NH₂, for L^1-7, respectively; in L⁸ isonicotinohydrazide was used instead of benzylhydrazide). Cu(II) complexes were prepared by reaction of each benzoylhydrazone with Cu(II) acetate. All compounds were characterized by elemental analysis and mass spectrometry as well as by FTIR, UV-visible absorption, NMR or electron paramagnetic resonance spectroscopies. Complexes isolated in the solid state (1-8) are either formulated as [Cu(HL)acetate] (with L¹ and L⁴) or as [Cu(Lⁿ)]₃ (n = 2, 3, 5, 6, 7 and 8). Single crystal X-ray diffraction studies were done for L⁵ and [Cu(L⁵)]₃, confirming the trinuclear formulation of several complexes. Proton dissociation constants, lipophilicity and solubility were determined for all free ligands by UV-Vis spectrophotometry in 30% (v/v) DMSO/H₂O. Formation constants were determined for [Cu(LH)], [Cu(L)] and [Cu(LH_-1)] for L = L¹, L⁵ and L⁶, and also [Cu(LH_-2)] for L = L⁶, and binding modes are proposed, [Cu(L)] predominating at physiological pH. The redox properties of complexes formed with L¹, L⁵ and L⁶ are investigated by cyclic voltammetry; the formal redox potentials fall in the range of +377 to +395 mV vs. NHE. The binding of the Cu(II)-complexes to bovine serum albumin was evaluated by fluorescence spectroscopy, showing moderate-to-strong interaction and suggesting formation of a ground state complex. The interaction of L¹, L³, L⁵ and L⁷, and of the corresponding complexes with calf thymus DNA was evaluated by thermal denaturation. The antiproliferative activity of all compounds was evaluated in malignant melanoma (A-375) and lung (A-549) cancer cells. The complexes show higher activity than the corresponding free ligand, and most complexes are more active than cisplatin. Compounds 1, 3, 5, and 8 were selected for additional studies: while these complexes induce reactive oxygen species and double-strand breaks in both cancer cells, their ability to induce cell-death by apoptosis varies. Within the set of compounds tested, 8 emerges as the most promising one, presenting low IC₅₀ values, and high induction of oxidative stress and DNA damage, which eventually lead to high rates of apoptosis.

Investigations on Anticancer Potentials by DNA Binding and Cytotoxicity Studies for Newly Synthesized and Characterized Imidazolidine and Thiazolidine-Based Isatin Derivatives

Imidazolidine and thiazolidine-based isatin derivatives (IST-01-04) were synthesized, characterized, and tested for their interactions with ds-DNA. Theoretical and experimental findings showed good compatibility and indicated compound-DNA binding by mixed mode of interactions. The evaluated binding parameters, i.e., binding constant (Kb), free energy change (ΔG), and binding site sizes (n), inferred comparatively greater and more spontaneous binding interactions of IST-02 and then IST-04 with the DNA, among all compounds tested under physiological pH and temperature (7.4, 37 °C). The cytotoxic activity of all compounds was assessed against HeLa (cervical carcinoma), MCF-7 (breast carcinoma), and HuH-7 (liver carcinoma), as well as normal HEK-293 (human embryonic kidney) cell lines. Among all compounds, IST-02 and 04 were found to be cytotoxic against HuH-7 cell lines with percentage cell toxicity of 75% and 66%, respectively, at 500 ng/µL dosage. Moreover, HEK-293 cells exhibit tolerance to the increasing drug concentration, suggesting these two compounds are less cytotoxic against normal cell lines compared to cancer cell lines. Hence, both DNA binding and cytotoxicity studies proved imidazolidine (IST-02) and thiazolidine (IST-04)-based isatin derivatives as potent anticancer drug candidates among which imidazolidine (IST-02) is comparatively the more promising.

In silico studies of interactions of peptide-conjugated cholesterol metabolites and betulinic acid with EGFR, LDR, and N-terminal fragment of CCKA receptors

In this work, we designed three new ligands by conjugating cholesterol metabolites 3-hydroxy-5-cholestenoic acid (3-HC) and 3-oxo-4-cholestenoic acid (3-OC) and the natural tri-terpenoid betulinic acid with the tumor-targeting peptide YHWYGYTPQNVI. Molecular interactions with the unconjugated peptide and the conjugates were examined with three receptors that are commonly overexpressed in pancreatic adenocarcinoma cells using ligand docking and molecular dynamics. This study demonstrated the utility of the designed conjugates as a valuable scaffold for potentially targeting EGFR and LDLR receptors. Our results indicate that the conjugates showed strong binding affinities and formation of stable complexes with EGFR, while the unconjugated peptide, BT-peptide conjugate, an 3-HC-peptide conjugate showed the formation of fairly stable complexes with LDLR receptor. For EGFR, two receptor kinase domains were explored. Interactions with the N-terminal domain of CCKA-R were relatively weaker. For LDLR, binding occurred in the beta-propeller region. For the N-terminal fragment of CCKA-R, the conjugates induced significant conformational changes in the receptor. The molecular dynamic simulations for 100 ns demonstrate that BT-peptide conjugates and the unconjugated peptide had the highest binding and formed the most stable complexes with EGFR. RMSD and trajectory analyses indicate that these molecules transit to a dynamically stable configuration in most cases within 60 ns. NMA analysis indicated that amongst the conjugates that showed relatively higher interactions with the respective receptors, the highest potential for deformability was seen for the N-terminal-47 amino acid region of the CCKA-R receptor with and the lowest for the LDLR-receptor. Thus, the newly designed compounds may be evaluated in the future toward developing drug delivery materials for targeting tumor cells overexpressing LDLR or EGFR.