The continuous search for new molecules with therapeutic abilities has led to the synthesis and characterization of a large number of metal complexes, proven to exhibit potential as pharmacological agents through their antibacterial, antiviral, antifungal and antineoplastic properties. As serum albumins play a key role in drug pharmacokinetics and pharmacodynamics, the study of coordination compounds affinity towards this class of proteins, as well as understanding the mechanism through which they interact is crucial. The aim of this review is to focus on the structure and biological functions of bovine serum albumin, the design of metal complexes that are able to bind to the biomolecule, as well as the experimental techniques employed in the study and evaluation of these interactions. Keywords: drug-protein interaction, coordination complex, fluorescence spectroscopy, UV-Vis absorption spectroscopy.

Four complexes of essential metal ions, Cu(II) and Ni(II), with the new sulfonamide ligand N-(pyridin-2-ylmethyl)quinoline-8-sulfonamide (HQSMP) were synthesized and physicochemically and structurally characterized. Complex [Cu(QSMP)Cl]_n (2) consists of a polymeric chain formed by distorted square pyramidal units. In 2, the sulfonamide ligand acts as a bridge coordinating to one Cu(II) through its three N atoms and to another metal ion via one O atom in the sulfonamido group, while the pentacoordinate complex [Cu(QSMP)(C₆H₅COO)] (3) presents a highly distorted square pyramidal geometry. Complex [Ni(QSMP)(C₆H₅COO)(CH₃OH)][Ni(QSMP)(CH₃COO)(CH₃OH)] (4) consists of two mononuclear entities containing different anion coligands, either a benzoate or an acetate group. Both units exhibit a distorted octahedral geometry. The interaction of the complexes with CT-DNA was studied by means of UV-Vis and fluorescence spectroscopy, interestingly revealing that the Ni(II) complex presents the highest affinity towards the nucleic acid. Complexes 1 and 2 are able to cleave DNA. Both compounds show promising nuclease activity at relatively low concentrations by mediating the production of a reactive oxygen species (ROS). The interaction of the four complexes with bovine serum albumin (BSA) was also investigated, showing that the compounds can bind to serum proteins. The antitumor potential of complexes 1 and 2 was evaluated against the A549 lung adenocarcinoma cell line, revealing cytotoxic properties that were both dose- and time-dependent.

The current study began with the following question: Is smoking a balanced factor between human body systems? One of the particular features of the oral cavity is its localization at the gateway of respiratory and digestive. Morphologically, the oral cavity encompasses a complex association of soft tissues, hard tissues, salivary glands, and taste receptors. The main purpose of this study was to analyze the tobacco residues (TAR) deposited on dental materials and the alterations of artificial saliva that comes into contact with tobacco smoke, by obtaining a solution of cigarette smoke extracts (CSE) after 5, 10, 15, and 20 tobacco cigarettes. According to LC-MS analysis and FT-IR spectra, carbonyl compounds, phenols, and carboxylic acids are present in CSE, which could explain the pH decrease and acid characteristic. Moreover, the CSE solution was added to the culture medium of Mesenchymal Stem Cells (MSCs) to evaluate the cytotoxicity. The MTT study revealed decreased MSC viability; morphological changes and cell death were more intense at higher doses of CSE added to the culture medium. Scanning Electron Microscopy (SEM) indicated cellular ruffling and irregular cell surface under higher concentrations of CSE-15 and CSE-20 in culture media, which is a characteristic feature demonstrating the membrane stress. In conclusion, the present study, with its limitations, showed the negative cellular effects of tobacco cigarette smoking and the impact of this habit on the oral cavity homeostasis.

In the field of drug design and the continuous search for new targeted and safe therapeutic options, metal complexes remain one of the most intensely studied classes of compounds, especially as potential antitumor and antibacterial agents