Logo
User Name

Safija Herenda

University of Sarajevo

Društvene mreže:

Jovana S. Dragojević, Žiko B. Milanović, Kristina Milisavljević, Milena Milutinović, S. Herenda, E. Hasković, N. Vanis, V. Divac, Marina D. Kostić

The search for new anticancer agents with improved efficacy and reduced toxicity has intensified interest in metal-based compounds. In this study, two novel palladium(II) complexes, synthesized from Schiff base ligands derived from 5-chloro-salicylaldehyde and p-hydroxybenzylamine or tyramine, were chemically characterized and biologically evaluated. Both complexes exhibited significant cytotoxic activity against the MCF-7 breast cancer cell line in a dose- and time-dependent manner, with Pd2 showing slightly higher potency. Morphological analysis of treated cells indicated that apoptosis is the predominant mechanism of cell death. To gain deeper insight into the potential mechanisms underlying the observed anticancer activity, several biologically relevant targets were investigated. Enzyme kinetics revealed that the complexes act as uncompetitive inhibitors of liver catalase, suggesting a possible role in the induction of oxidative stress. Fluorescence studies demonstrated that Pd2 interacts with CT-DNA through combined intercalative and minor groove binding modes and exhibits significant binding affinity toward human serum albumin, predominantly at Sudlow’s site I. Molecular docking analysis further supported favorable interactions with catalase, estrogen receptor α, and B-form DNA, providing structural insight into the experimentally observed biological effects. Overall, the study explores multiple potential mechanisms of anticancer action, underscoring the promising therapeutic potential of these palladium(II) complexes, while antitumor activity has been initially assessed using a MCF-7 cell line as a preliminary model.

Renato Tomaš, O. Politeo, M. Vraneš, M. Guettari, S. Herenda, Martina Požar

Solvent structure-making is an important feature of molecular organization in liquids as it shapes thermodynamic, dynamic and reactive properties. In this paper, we combine experimental and computational approaches to elucidate the structure-making behaviour of trans-4-hydroxy-3-methoxycinnamic acid (ferulic acid, FA) in a series of solvents: the protic alcohols methanol, ethanol, and 2-propanol, and the aprotic solvents tetrahydrofuran (THF) and dimethyl sulfoxide (DMSO). Precise viscometric measurements over 11 temperatures in the molality range from ∼0.01 to ∼0.5 mol kg-1 reveal that FA acts as a structure-maker across all solutions. Molecular dynamics simulations complement these findings, revealing marked cross-species correlations and mixed clusters in protic solvents. Hydrogen-bond analysis highlights the long lifetimes of cross-species hydrogen bonds, underscoring the dual donor-acceptor capacity of FA. The insights from experiments and simulations provide a molecular foundation for understanding how solute-induced structure-making by ferulic acid influences solvent organization, and ultimately, properties such as viscosity and antioxidant performance.

Jelena Ostojic, S. Herenda, Sabina Gojak-Salimović, Sanja Pržulj, Semira Galijasevic, Mladen Miloš

S. Herenda, Emir Osmic, Muamer Dizdar, Sabina Prevljak, E. Hasković

Benzodiazepines are used for their anxiolytic, antiepileptic, muscle relaxant and hypnotic effects. In vitro, diazepam is predominantly metabolized to temazepam and nordiazepam (N-desmethyldiazepam). Since acetylcholinesterase is involved in the metabolism of diazepam, inhibition of the enzyme activity may have a significant effect on the therapeutic effect of the drug. To determine the inhibitory effect of 2,2,4-trimethyl-2,3-dihydro-1H-benzo[b][1,4]diazepine on acetylcholinesterase enzyme activity by conducting a comprehensive analysis that includes: measuring the enzyme activity in the presence of various concentrations of the inhibitor, determining the type of inhibition through kinetic studies, and assessing the potential therapeutic applications of the inhibitor in conditions associated with acetylcholinesterase dysfunction. In this study, the inhibitory properties of 2,2,4-trimethyl-2,3-dihydro-1-Hbenzo[ b][1,4]diazepine on the activity of the enzyme acetylcholinesterase were tested spectrophotometrically at three different temperatures of 25℃, 30℃, and 37℃. The substance was synthesized by a condensation reaction between o-phenyldiamine and acetone in the presence of phosphorus oxychloride on solid support (MgO). The solid product was obtained by crystallization from n-hexane. Each tested sample contained an appropriate concentration of the substrate acetylcholine iodide (AChI) in the range from 1.00 to 4.00 mmol·L-1; 5,5-dithiobis(2-nitrobenzoic acid) (DTNB) concentration 3 mmolL-1, phosphate buffer (KH2PO4/K2HPO4) pH value 8, tested substance concentration (17.70, 35.40, 53.10 mmol·L-1), and acetylcholinesterase solution (AChE) activity 0.54 UmL-1. Using the spectrophotometric method, it was concluded that the examined diazepine shows a competitive type of inhibition on the enzyme acetylcholinesterase. 30°C was determined to be the optimal assay temperature. The highest inhibition was observed at 25°C using 53.10 mmol·L⁻¹ of the inhibitor. As the temperature increases, the inhibition decreases. Based on the Lineweaver-Burk diagram, we gain insight into the type of inhibition exhibited by the synthesized compound. The intercept on the ordinate remains unchanged; the slope of the line increases, and the intercept on the abscissa decreases, indicating that it is a competitive inhibition. Considering the results obtained by spectrophotometric analysis, it was concluded that the enzyme acetylcholinesterase follows the Michaelis-Menten model. It has been proven that the synthesized compound exhibits inhibitory properties on the activity of acetylcholinesterase.

S. Herenda, Selma Fetahović, Nataša G. Đorđević, Tamara Klisara, E. Hasković, Sabina Prevljak

Enzymes are catalysts of biological origin, and according to their chemical composition, they are simple or complex proteins. There are several theories about the enzyme's mechanism of action. Today, the Michaelis-Menten theory is generally accepted. According to this theory, during enzymatic reactions, an intermediate compound is created between the enzyme and the substrate. After the formation of this complex, the enzyme catalyzes a chemical reaction that changes the substrate into another molecule, which we call the product. The product is then separated and released from the active site of the enzyme, which is then ready to bind the next substrate molecule. Enzyme activity can be affected by different molecules. The purpose of this study is to use the spectrophotometric approach to determine whether sodium benzoate and ascorbic acid (vitamin C) serve as activators or inhibitors of enzymatic reactions. The obtained results show that both additives bind to the enzyme-substrate complex, causing non-competitive inhibition.

S. Herenda, Merima Begovic, E. Hasković, V. Asanović

<p style="text-align: justify;">Shape memory alloys are of great commercial importance from biomedical applications to smart materials. The electrochemical behavior of Cu-Al-Zn alloy in phosphate buffer without and in the presence of amino acid was investigated. Electrochemical researches were performed in a traditional three-electrode system by means of the Tafel extrapolation method. The results showed that the presence of amino acid leads to a decrease in the corrosion rate and the density (values) of the corrosion current, which indicates that the tested inhibitor is efficient.</p>

S. Herenda, Ivana Carev, Denis Hasković, Sabina Prevljak, S. Causevic, E. Hasković

In this study, the impact of glucocorticoid, betamethasone dipropionate on enzyme activity in vitro and its effects on hematological parameters in vivo was investigated. The immobilized catalase, crucial for cell oxidative stress response via hydrogen peroxide reduction, exhibited a robust electrocatalytic response, maintaining its biological activity. The in vitro inhibition kinetics of catalase, as determined by electrocatalytic methods and expressed using Lineweaver-Burke diagrams, revealed an uncompetitive type of inhibition with altered Imax and Km in the presence of a range of betamethasone dipropionate concentrations. The in vivo experiments conducted on Rattus norvegicus demonstrated significant alterations in hematological parameters following betamethasone dipropionate administration. These changes included a decrease in erythrocyte count, an increase in hemoglobin, a reduction in mean corpuscular volume (MCV), and an elevation in mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC). Notably, the leukocyte counts substantially increased. The observed hematological shifts suggest an impact of betamethasone dipropionate on the hematopoietic system, reinforcing the need for cautious corticosteroid administration. The findings underline the necessity for judicious corticosteroid treatment, acknowledging both enzymatic and systemic repercussions.

S. Herenda, V. Asanović, E. Hasković, Dragan Radonjić, J. Šćepanović

Abstract The amperometric biosensor was created using a flat sheet of the Cu-Zn-Al shape memory alloy, with a shiny surface and uniform thickness below 1 mm. The high biocompatibility and a large specific surface area for enzyme loading are evaluated. In vitro biomedical corrosion testing of samples revealed successful immobilization of catalase, which has undergone quasi-reversible electron transfer from the surface and saline solution. A catalase that had been immobilized retained its basic structure and bioactivity and demonstrated a remarkable electrocatalytic response to hydrogen peroxide reduction. The reduction of hydrogen peroxide on the catalase-modified Cu-25.38Zn-3.3Al alloy was investigated using hydrodynamic amperometry in both the absence and presence of l-cysteine and K2[B3O3F4OH] inhibitors. Catalytic reduction currents have increased as a result of the gradual increase in hydrogen peroxide concentration. The study on enzyme activity inhibition has shown a lower corrosion rate of catalase-modified bioalloy than the initial sample because inhibitor ions occupy all sites of the immobilized enzyme.

E. Hasković, S. Herenda, Amina Herenda, Denis Hasković, Ena Hasković, A. Selimović

Glucocorticoids prevent or suppress the full inflammatory response to the infectious, immunological or physical agents by inhibiting early inflammatory events such as edema or cell exudation. The main effect of glucocorticoids on the inflammatory process is the inhibition or recruitment of neutrophils and monocytes. In this study, the effect of the glucocorticoid betamethasone on the hematological parameters of rats of the species Rattus norvegicus Berkenhout 1769 was examined in vivo. Betamethasone has been shown to affect the values of hematological parameters four hours after application and leads to a significant decrease in the prevalence of lymphocytes and monocytes, but also leads to a statistically significant increase in erythrocyte count, hemoglobin concentration and hematocrit values.

...
...
...

Pretplatite se na novosti o BH Akademskom Imeniku

Ova stranica koristi kolačiće da bi vam pružila najbolje iskustvo

Saznaj više