Publications

Abstract <jats:p>Pollution of soils by heavy metals (HM) is a concerning result of anthropogenic activities. Iron (Fe) and silver (Ag) are HM-deemed essential and non-essential for plants and can induce toxicity when in excess. Metallothioneins (MTs) are small Cys-rich proteins involved in HM binding and oxidative stress mitigation. This study focused on Arabidopsis thaliana MTs types I, II, and III involvement in response to increasing concentrations of Fe and Ag in an organ-specific way - shoots and roots - through RT-qPCR analysis 21 days after germination, as well as biometric and biochemical assessments. The in vivo heterologous expression of AtMT2b in Nicotiana tabacum leaves was performed. Both HM reduced plant growth, with Fe accumulating dose-dependently in both shoots and roots, while Ag mainly accumulated in roots, albeit only at the highest concentration in shoots. Fe exposure caused little change in MT expression, whereas Ag strongly induced it in shoots and, to a lesser extent, in roots (particularly AtMT1a and AtMT1c). Biochemical analyses revealed distinct stress responses: Fe increased lipid peroxidation (MDA) and antioxidant compounds (GSH, thiols) mainly in shoots, while Ag triggered oxidative metabolism predominantly in shoots, with elevated HO, MDA, GSH, thiols, and proline levels. Both HM reduced photosynthetic pigments, notably -carotenes with Fe, and chlorophylls, lutein, and -carotenes with Ag. In vivo localisation showed AtMT2b to be cytosolic. Overall, Fe and Ag induced stress in A. thaliana with organ-specific responses, and MTs played a minor role in Fe tolerance but were strongly activated by Ag, especially in shoots.</jats:p>

Abstract Assisted reproductive technologies (ART) use has increased over the past decades. However, reports concerning ART's low efficiency continue to emerge, citing causes related to lower embryo quality and pregnancy rates compared to their in vivo counterparts. One of the setbacks of ART is oxidative stress, which can impair embryo developmental rates. Mitochondrial redox and energetic homeostasis determine both cell survival and death, so mitochondria are a key target for therapeutic intervention strategies. In the present work, our objective was to improve the quality of viable embryos by adding new mitochondria-targeted antioxidants in the embryo culture media to reduce oxidative stress. Two naturally derived antioxidants synthesized by our team, AntiOxBEN2 and AntiOxCIN4, based on hydroxybenzoic and hydroxycinnamic scaffolds, respectively, were studied in two different experimental protocols (here called experiments). The first experiment investigated the effects of the antioxidants on embryo development to determine their optimal concentrations. The first assay of the first experiment focused on the effects of AntiOxCIN4 at concentrations of 1, 2.5, and 10 mu M, while the second assay focused on the effects of AntiOxBEN2 at the same concentrations. A control group without supplementation was run simultaneously. The second experiment aimed to compare the best concentrations of these antioxidant molecules in the embryo culture media and their effect on embryos' resistance to vitrification/warming. In each experiment, the embryos were morphologically evaluated, and the total and viable cell numbers were examined. Reactive oxygen species (ROS) and mitochondrial polarization were also evaluated using specific fluorescent dyes. In experiment 1, an increased embryo quality was identified by using 2.5 mu M AntiOxCIN4 (p = 0.03) and 2.5 mu M AntiOxBEN2 (p = 0.001). Moreover, blastocysts supplemented with 2.5 mu M AntiOxCIN4 had higher viability (p = 0.008), while those supplemented with 2.5 mu M AntiOxBEN2 presented a greater total cell number (p = 0.01). An improvement in embryo cryosurvival following the supplementation during the culture process with either antioxidant was identified in experiment 2, with superior expansion scores after vitrification/warming and culture (2.5 mu M AntiOxCIN4, p = 0.056 and 2.5 mu M AntiOxBEN2, p = 0.059). In conclusion, both AntiOxCIN4 and AntiOxBEN2 had a beneficial effect on embryo development and cryosurvival, suggesting a potential intervention to reduce oxidative stress in assisted reproductive technologies.

Abstract Metabolic dysfunction-associated steatotic liver disease (MASLD) affects approximately 30 % of the global population. Its progression is commonly linked to excessive hepatic fat accumulation, elevated oxidative stress, and impaired mitochondrial function. Given the central role of mitochondria in cellular energy metabolism and redox balance, mitochondria-targeted bioactive molecules have emerged as a promising strategy for the prevention and treatment of MASLD. To this end, we develop AntiOxBEN<inf>2</inf>, a mitochondria-targeted compound generated by conjugating the antioxidant moiety of gallic acid with the lipophilic triphenylphosphonium cation . This design enables selective accumulation of AntiOxBEN<inf>2</inf> in the mitochondrial matrix, taking advantage of the organelle’s negative membrane potential. In multiple in vitro disease model s , AntiOxBEN<inf>2</inf> has demonstrated remarkable antioxidant properties, effectively mitigating oxidative stress and preserving mitochondrial function. However, effects on cellular and mitochondrial energy metabolism in vivo remain unexplored. In the present study, we tested whether chronic peripheral administration of AntiOxBEN<inf>2</inf> (0.5 or 2.5 mg/kg, 3x/week) could prevent MASLD development in male and female C57BL/6 J mice fed with a 30 % high-fat, 30 % high-sucrose (Western Diet, WD) diet for 16 weeks. Our results demonstrate that AntiOxBEN<inf>2</inf> treatment significantly reduced hepatic lipid accumulation in both sexes without affecting body weight. This reduction was accompanied by improvements in mitochondrial function, including enhanced fatty acid oxidation (FAO) and increased activities of mitochondrial electron transport chain (ETC) complexes. Moreover, AntiOxBEN<inf>2</inf> administration lowered circulating levels of hepatic damage markers (ALT and AST), as well as insulin and leptin. Notably, a clear sexual dimorphism was observed, with female mice displaying a more pronounced improvement in mitochondrial parameters. Collectively, these findings highlight the therapeutic potential of AntiOxBEN<inf>2</inf> for the prevention and/or treatment of MASLD. © © 2026. Published by Elsevier Masson SAS.

Abstract Pseudomonas aeruginosa biofilm-associated infections present higher recalcitrance to antimicrobial treatments, contributing to persistent and difficult-to-treat infections. Quorum sensing (QS) regulates various cellular processes that are important for the establishment and survival of microbial communities on the host. However, QS inhibitors for the treatment of P. aeruginosa biofilms remain under-researched, partly due to the complexity of QS signalling pathways and the challenge of developing non-toxic inhibitors. Herein, the bioactivity of 2-{(2E)-2-[1-(pyridin-2-yl)ethylidene]hydrazinyl}-1,3-thiazole-4-carboxylic acid (TTNF37), a novel pyridine-based thiazolyl-hydrazone (PTH), was investigated. The compound antimicrobial activity was evaluated against a broad spectrum of microorganisms, its antioxidant potential was assessed using different assays, and its QS-inhibitory effect on P. aeruginosa was studied using bioreporter strains. The effect on P. aeruginosa biofilm formation was analysed in terms of biomass, culturability, and metabolic activity, structure, and cell membrane integrity, while virulence factors were evaluated through absorbance measurements. In addition, molecular docking studies were performed to predict the drug's interactions with essential QS proteins and biological targets. TTNF37 exhibited potent antimicrobial activity with low to moderate minimum inhibitory concentrations against clinically relevant Gram-negative and Gram-positive bacteria, as well as fungi and yeasts. It also showed antioxidant activity, with variable effectiveness across different radicals and systems. TTNF37 inhibited the 3-oxo-C12-HSL-dependent QS system of P. aeruginosa in a dose-dependent manner, with reductions ranging from 26% to 98%. It also impaired the production and detection of 3-oxo-C12-HSL, resulting in a 56% and 65% decrease in bioluminescence, respectively. Molecular docking studies revealed strong binding interactions with LasI and LasR proteins, with affinity values exceeding those of furvina, a known potent QS inhibitor. Molecular dynamics simulations validated stable TTNF37 binding to LasR and LasI. Both experimental and docking data indicate a significant interaction with human serum albumin (HSA). TTNF37 also significantly reduced pyocyanin production and prevented biofilm set-up with a reduction of 50% in biomass with pronounced alterations in biofilm structure. These results indicate the potential of TTNF37 and related PTHs for treating biofilm-associated infections.

Abstract The high costs of equipment and maintenance for Chemistry laboratories are a barrier to quality education in this science. However, the emergence of user-friendly and low-cost technological tools helps to mitigate this problem. This paper presents a STEM proposal for exploring distillation collaboratively in a remote laboratory with live data transmission and sharing online. The approach was analyzed by four teachers from Mozambique who, in that context, highlighted the positive potential for knowledge exchange between schools and cultures and the negative lack of technological means in schools for its implementation. They recognize great potential for implementation in higher education, as institutions have better resources. Thus, richer learning experiences can be promoted for all participants.

Abstract Student-centred learning requires a variety of approaches, such as inquiry-based learning and the tackling of authentic and problem-based learning activities, to make the teaching and learning process more meaningful and to encourage students to participate more actively in class. The inquiry approach enables students to investigate solutions to real problems, awakening their need to ask questions, design and conduct research, collect and analyse data, interpret results and present them in a structured way. This study investigates the influence of an inquiry-based science education (IBSE) module on the development of oral and written communication skills among 10th grade students. The study is set in a secondary school context and focuses on a problem-based learning approach centred around gases and dispersions. A total of 111 students participated in this one-group post-assessment qualitative study, where evaluation rubrics were applied to assess students' written and oral communication, focusing on correctness, clarity and mastery of scientific language. The results showed that the majority of students performed well in both written and oral tasks, demonstrating improved scientific communication skills. This suggests that IBSE, particularly in the context of secondary education, can be an effective approach to fostering students' abilities to communicate scientific concepts. The study has implications for enhancing pedagogical practices and encourages further research on the long-term effects of IBSE on student learning.

Abstract An acid-base titrator connected to the Internet was developed for conducting remote investigative experiments. The experiment was broadcasted in a high school senior classroom, with the presence of a facilitating teacher. The activity required students to determine the indicator present in the solution. To carry out the activity, students added acid or base to sweep the pH range from 0 to 14 and noted the corresponding coloration to the pH through video analysis. The results obtained were very satisfactory, both in the identification of the indicator and in the acceptance and engagement of the students in the activity.

Abstract Educators cannot overlook the affect's potential for students’ educational success. In this study, affective analogies are proposed as a didactic resource to foster students’ affect for chemistry learning and positive attitudes towards the physics-chemistry subject. To examine the influence of the affective analogies on it, we grouped contents of this subject into three modules (Kinetic-molecular theory; Quantum model of the atom; Chemical elements and their isotopes) and developed analogies between chemistry and music for each (affective analogies), which were then compared to homologous undifferentiated analogies (familiar analogues without affective qualities in addition) and teaching strategies without analogies. An explanatory mixed-method design was used. Data were collected through questionnaires and interviews, with a convenience sample of 147 students attending the 7th grade of a middle school music course. The results show that the affective dimension of analogies promotes positive affect for learning at much higher levels than the familiar dimension. We proposed a mechanism through which this occurs. However, if analogies are familiar, it seems that their positive affective dimension is not as important for students’ learning levels. More than interesting, analogies should perhaps be non-aversive. As for attitudes towards physics-chemistry, teaching with affective analogies is the most beneficial strategy. This results from students’ perception that this teaching approach promoted positive affect for the study of physics-chemistry, compared to undifferentiated analogies and without analogies. Furthermore, it favoured learning and achievement in physics-chemistry, compared to the absence of analogies, because without analogies it is more difficult to understand abstract or difficult concepts. © 2025 Fırtına Akademi A.Ş. All rights reserved. This article published by TUSED is released under the CC BY-NC-ND license.

Abstract New psychoactive substances (NPS) are designed to evade legal regulation while mimicking the effects of classic illicit drugs such as 3,4-methylenedioxymethamphetamine (MDMA). This category includes phenethylamine derivatives, such as the psychedelic 2C and NBOMe drugs. Given the lack of data regarding the toxicological profile of these substances, the goal of this study was to evaluate the neurotoxicity of 2C-I and 25I-NBOMe and explore their neurotoxic pathways. Lower EC50 values, in both NR uptake and MTT reduction assays in differentiated SH-SY5Y cells and primary rat cortical cultures, revealed that 25I-NBOMe is significantly more cytotoxic than 2C-I, likely due to its higher lipophilicity. Both drugs triggered severe mitochondrial dysfunction, characterized by decreased intracellular ATP levels and mitochondrial membrane depolarization, although no significant changes in intracellular ROS/RNS levels were observed. Additionally, 25I-NBOMe increased the intracellular Ca2* levels. Apoptosis was an observed mechanism of cell death for both drugs, as demonstrated by a significant increase in the number of cells undergoing early apoptosis (AnV+/PI-) and late apoptosis/necrosis (AnV+/PI+). However, only 2C-I induced autophagy and strongly triggered caspase-3 activation. This suggests that 2C-I induces caspase-3-dependent apoptosis, whereas 25I-NBOMe may also induce apoptosis through a caspase-3-independent pathway, possibly involving increased intracellular Ca2* levels and direct mitochondrial damage. These findings underscore the complex interplay between mitochondrial dysfunction, calcium dysregulation, and cell death pathways, highlighting the central role of mitochondria in the cytotoxicity of 2C-I and 25INBOMe.

Abstract Edaravone is one of the treatment options for Amyotrophic Lateral Sclerosis, but its therapeutic efficacy is limited due to the incapacity to cross the blood-brain barrier, as well as its short life span and poor stability, which is ultimately caused by its tautomerism in physiological condions. This work presents an overview about the use of several nanoformulations based on polymeric, protein, lipidic, or hybrid structure as suitable and stable drug delivery systems for encapsulating edaravone. We also evaluated the functionalization of nanoparticles with pegylated chains using the polyethylene glycol or tocopherol polyethylene glycol succinate and the possibility of preparing polymeric nanoparticles at different pH (7.4, 9, and 11). Edaravone was sucessfully encapsulated in polymeric, lipid-polymer hybrid, and lipidic nanoparticles. The use of higher pH values in the synthesis of polymeric nanoparticles has led to a decrease in nanoparticle size and an increase in the percentage of encapsulation efficiency. However, the resulting nanoformulations are not stable. Only polymeric and hybrid nanoparticles showed good stability over 80 days of storage, mainly at 4 degrees C. Overall, the nanoformulations tested did not show cytotoxicity in the SH-SY5Y cell line except the nanostructured lipid carrier formulations that showed some cytotoxicity possibly due to lipidic peroxidation. In conclusion, this work shows that edaravone can be encapsulated in different nanocarriers that could act as an interesting alternative for the treatment of Amyotrophic Lateral Sclerosis.