Online ISSN:
3042-1772

Volume 1 , Issue 1, (2024)

Published:
29.08.2024.

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Issue 1 - 2024

Published: 29.08.2024.

Authors in this issue:

Abdelhameed Mohamed, Abhipsita De, Adam Sikora, Adrianna Skoneczna, Agnes Tessier, Albrecht Stroh, Aleksandra Andreyeva, Aleksandra Drašković, Aleksandra Korać, Aleksandra Yu Andreyeva, Aleksandra Cvoro, Aleksandra Jankovic, Aleksandra Korac, Aleksandra Ristić Fira, Aleksandra Stanković, Alena Pecinová, Alessandra Pecorelli, Alex Lyakhovich, Ana Popović Bijelić, Ana Ružanović, Ana Vesković, Ana Djordjevic, Ana Kijanović, Ana Ledo, Ana Ninić, Ana Penezic, Ana Teofilovic, Anastasia A Tkachuk, Anastasia Ioanna Papantonaki, Anastasiya Volkova, Andrea Vallese, Andrea Pozzer, Andreas Daiber, Andreas Vitsos, Aneta Wiesyk, Anna Giorak, Anna Guiotto, Anna V Goropashnaya, Anne-Françoise Rousseau, Anthony L. Moore, Arijan Valar, Arvand Haschemi, Azra Guzonjić, Barbara Ostanek, Bárbara S. Rocha, Barry Halliwell, Bato Korac, Bengu Cetinkaya, Biljana Srdić Galić, Biljana Srdic-Galic, Blanca Romero-Llopis, Blandine Poulet, Bojan Labachevski, Branislav Milovanović, Branka R Gavrilović, Bruna Rafaela Pereira Resende, Can Tunçay, Cândida Dias, Carlo Cervellati, Carlo Viscomi, Caroline Le Goff, Cátia F. Lourenço, Cátia Lourenço, Cemile Uslu, Chiranjit Panja, Christina Barda, Christopher Kremslehner, Dalila Laoudj-Chevinesse, Daniel C Moreira, Daniela Ardalic, Daniela Caporossi, Danijela Vojnovic Milutinovic, Danilo Cetic, Darko Davitkov, David Nußbaum, Dejan Stevanovic, Diana Mikhailova, Dimitra Ieronymaki, Dimitrios Katsiris, Dimitrios Vlachodimitropoulos, Dirk Cleppien, Dominika Mihalikova, Dragana Jovanović, Dragana Robajac, Dragica Zendelovska, Eda Kapan, Ekaterina S. Kladchenko, Elina S Chelebieva, Elisabeth Ponweiser, Elizabeth Hood, Emilija Atanasovska, Ena Šimunić, Erdi Sozen, Erika Fernandez-Vizarra, Etienne Cavalier, Etna Abad, Evica Dincić, Federico V Pallardó, Filip Janjić, Florian Gruber, Francesca Marcato, Francesco Galli, Fulvio Ursini, Gaelle Gendronneau, Georgios Gkikas, Georgios Parthymos, Giada Petringa, Giuseppe Valacchi, Giuseppe Poli, Goran Miljus, Guilherme Horta, Guillermo Puertas-Frias, Hagar Fadda, Hamada Elwan, Hansjörg Habisch, Hemdan Mahmoud, Henning Ubbens, Homer Black, Igor Mindukshev, Igor Golic, Iñigo Yoldi Bergua, Ioannis Sfiniadakis, Ionela Mariana Nagelreiter, Irina Iskortseva, Isidora Protic, Iva I. Podgorski, Iva Perović-Blagojević, Ivan Spasojević, Ivan Petrović, Ivana Simić, Ivana Kuntić, Jacek Zielonka, Janja Marc, Jaroslaw Ciesla, Jean-Olivier Defraigne, Jean-Paul Cheramy-Bien, Jelena Kotur Stevuljević, Jelena Kotur-Stevuljević, Jelena Francuski Andrić, Jelena Jevtic, Jelena P Gavrić, Jiayin Zheng, Jiří Neužil, João Gonçalves, João Laranjinha, Joël Pincemai, Johanne Anastassopoulou, Jonathan Maury, Jos Lelieveld, Joussef Hayek, Jovana Stevanovic, Jovana Kuveljić, Juan Sastre, Kelly L Drew, Kristina Spariosu, Kristýna Čunátová, Ksenija Vujacic-Mirski, Larin Deeb, Lazar Karić, Lea Strohm, Leonardo Nardi, Ljupka Gligorovska, Lorena Baquero, Lucija Dončević, Lukáš Alán, Maja Ajduković, Maja Bosković, Maja Vukobratovic, Maja Živković, Marek Vrbacký, María José Saucedo-Rodríguez, Maria Giakoumaki, Maria Kyriazi, Maria S Podolskaya, Maria Teresa Bayo Jimenez, Marie Vanišová, Marie Sophie Narzt, Marija Vasić, Marija Aleksic, Marija D. Milošević, Marija Petrushevska, Marija Popova-Labachevska, Marija Takić, Marijana Popović Hadžija, Marin Kuntić, Marko D Prokić, Marko Mirč, Marta Kaloper, Marta Roldán-Lázaro, Marta Sipko, Martina Marchetti-Deschmann, Masanta Suchismita, Matea Juric, Matthias Kohl, Matthias Oelze, Micael Hardy, Michael Schmeißer, Michaela Sochorová, Michail Christou Rallis, Michelangelo Mancuso, Milena Dimitrijević, Milena Cvijanović, Milena Radaković, Milica Mandic, Milica Kovačević Filipović, Milica Mamić, Milos Sunderic, Miloš Đorđević, Miloš Mitrović, Milos Vrataric, Minja Derikonjić, Mirjana Udicki, Miron Sopić, Mladen Paradžik, Mohamed Mohany, Natalija Samardzić, Nataša Tomašević Kolarov, Natasa Velickovic, Natasa Z Djordjevic, Natzi Sakalihasan, Nejla H Zupic, Nesrin Kartal Ozer, Nevena Đukić, Niki Chondrogianni, Ninoslav Mitic, Ognjen Radojicic, Olga L Gostyukhina, Olgica Nedic, Omar Hahad, Ondrej Kuda, Otilija Keta, Pablo Cirrone, Panagoula Pavlou, Petr Pecina, Phaedra Winstanley-Zarach, Pilar González-Cabo, Radmila Ristić, Raffaele Cerutti, Raheema Hassan Khan, Ratko Tomašević, Rita Noverques, Robert Belužić, Roman Maslanka, Ron Kohen, Roza Kucharczyk, Salim S. Al-Rejaie, Samuele Zoratto, Sandra Sobočanec, Sanja Erceg, Sanja Kovacevic, Sanja Milenkovic, Sanja Stojanovic, Sara Stojanovic, Sebastian Steven, Shaaban S. Elnesr, Slavica Ranković, Snežana Kovačević, Sophie Christelbach, Steffen Daub, Stephan Sudowe, Stevo Najman, Strahinja Đurić, Strahinja Djuric, Sven Danckwardt, Svetlana G Despotović, Sylwia Pilch, Tamara G Petrović, Tamara Lapeña, Tamara Zakic, Tanja Vukov, Tarun Pant, Tatiana B Sigacheva, Tatjana Ivković Kapicl, Tawfeeq Shekh-Ahmad, Thomas Berkemeier, Thomas Münzel, Tihomir Balog, Tijana B Radovanović, Tijana Vučić, Tobias Madl, Tomáš Mráček, Tomáš Čajka, Tristan Junglas, Tugce Demirel-Yalciner, Tuguldur Enkhbaatar, Ufuk Ersoy, Vadim B Fedorov, Valeria Cordone, Valeria Balmaceda, Vanja Pekovic-Vaughan, Vesna Ćeriman Krstić, Vesna Mandic Markovic, Vladana Petković, Vsevolod Belousov, Willem H Koppenol, Yara Shqair, Zana C Dolicanin, Zeljko Mikovic, Zeynep Ülker, Zorana Dobrijevic, Zorana Milosavljević, Zorka Drvendžija,

29.08.2024.

Professional paper

TUMOR SIZE AS THE BEST PREDICTOR FOR THE PRESENCE OF BREAST CANCER METASTASES IN AXILLARY LYMPH NODES

The metastasis of breast cancer to the axillary lymph nodes represents a crucial aspect of disease progression and prognostic evaluation. The presence of metastases in the axillary lymph nodes is a key indicator that breast cancer is in an advanced stage, which can influence the therapeutic approach and the patient's prognosis. For this reason, we conducted a study aimed at examining the factors that contribute to the presence of metastases in lymph nodes in our female population. This research represents a prospective study conducted at the Institute of Oncology of Vojvodina in Sremska Kamenica. The study included 72 female participants diagnosed with breast cancer who underwent surgery at the Institute of Oncology of Vojvodina and had not received preoperative chemotherapy or radiation therapy. Initially, anamnestic data were collected from the participants, followed by a pathohistological analysis of the tumor tissue samples, including immunohistochemical analysis. We examined the influence of age, tumor size, activity of estrogen, progesterone, and HER2 receptors (human epidermal growth factor receptor-2)  in tumors, as well as the occurrence of menarche and breastfeeding duration, on the presence of metastases in axillary lymph nodes. The results of binary logistic regression showed that the only significant predictor for the presence of metastases in axillary lymph nodes was tumor size (p=0.01, Wald=6.57, and Exp(B)=1.11), while the other examined predictors were not statistically significant (p>0.05). In our study population, the size of the breast cancer was crucial for the presence of metastases in the axillary lymph nodes.

This research was supported by the Science Fund of the Republic of Serbia, #7750238, Exploring new avenues in breast cancer research: Redox and metabolic reprogramming of cancer and associated adipose tissue - REFRAME.

Zorka Drvendžija, Mirjana Udicki, Tamara Zakić, Aleksandra Janković, Biljana Srdić Galić, Aleksandra Korać, Bato Korać

29.08.2024.

Professional paper

MITIGATION OF PM2.5-INDUCED CARDIOVASCULAR DAMAGE BY STATINS AND ACE INHIBITORS

Particulate matter (PM) is well recognized as the major contributor to the air pollution disease burden. Presently, the data pointing to the direct effects of PM on the cardiovascular health are numerous, but the mitigation strategies are still at the level of reduction of exposure. In the present study, we used a mouse model of real-life PM2.5 exposure treated with either a statin (atorvastatin) or an ACE inhibitor (captopril) in order to observe the potentially protective effects of cardiovascular drug treatment on the underlying mechanisms of detrimental, PM2.5-induced, cardiovascular effects. Captopril treatment mitigated the PM2.5-induced blood pressure while both drugs reduced selected markers of oxidative stress in the vasculature and heart. Both drugs were successful in mitigating the vascular oxidative stress by reducing the activation of the NADPH oxidase enzyme. In addition, both drugs were able to reverse the PM2.5-induced increase in vascular endothelin-1. The treatment also reduced the level of 3-NT positive proteins in the lung and mitigated the effects on dysregulated eNOS expression. Drugs did not mitigate the inflammatory response in the lung and in circulation with only captopril reducing the pulmonary IL-6, but not CD68 expression. In summary, ACE inhibitors can potentially mitigate the effects of PM2.5 on the vascular function and oxidative stress by lowering blood pressure and statins have a known antioxidant effect, e.g. via inhibition of NADPH oxidase. Our present data provide novel insights into possible mitigation strategies for PM2.5-induced cardiovascular disease. Since statins and ACE inhibitors represent first-line therapies for cardiovascular disease, CVD patients, e.g. with coronary artery disease, ischemic heart disease, and hypertension representing highly vulnerable groups for air pollution health effects, may benefit from pre-established therapies with these drugs to prevent additive cardiovascular damage by PM2.5 exposure.

Marin Kuntic, Tristan Junglas, Ivana Kuntic, Matthias Oelze, Lea Strohm, Henning Ubbens, Jiayin Zheng, Arijan Valar, Maria Teresa Bayo Jimenez, Omar Hahad, Thomas Münzel, Andreas Daiber

29.08.2024.

Professional paper

EFFECTS OF ARTIFICIAL LIGHT ON OXIDATIVE STRESS PARAMETERS IN AMPHIBIANS: A CASE STUDY OF HYLA ARBOREA

Human activity and rapid urbanization created disturbance factors that drastically changed natural habitats. The introduction of artificial light at night changed natural light-dark regimes affecting a range of biological processes. Disruption of circadian rhythm is linked with changes in endocrine and neurobiological systems that control hormonal regulation, food intake, metabolism, reproduction, and behavior of animals. Oxidative stress was suggested as a possible mechanism through which artificial light could affect an organism’s physiology and health. We examined the oxidative status of tree frog (Hyla arborea) under two artificial night light intensities 20 lux and 90 lux. Artificial light affects the antioxidant system of both larval and juvenile stages. Larvae had higher activity for glutathione peroxidase only for 90 lux, while greater lipid damage was observed in individuals under both light regimes compared to control. Juvenile individuals showed boosted antioxidant response seen through higher activities of superoxide dismutase, catalase, and glutathione peroxidase. Finally, development under artificial light led to higher levels of protein damage in juveniles. Artificial light at night acts primarily through direct effects and can persist across life stages. Overall results point out that exposure to artificial light alters physiological traits in amphibians, such as oxidative status that could have various consequences on individuals in natural populations.

Tamara G Petrović, Jelena P Gavrić, Svetlana G Despotović, Branka R Gavrilović, Tijana B Radovanović, Ana Kijanović, Marko Mirč, Tanja Vukov, Nevena Đukić, Nataša Tomašević Kolarov, Marko D Prokić

29.08.2024.

Professional paper

COMBINED EFFECTS OF GLYPHOSATE-BASED PESTICIDES AND ELEVATED TEMPERATURE ON OXIDATIVE STRESS PARAMETERS AND ACETYLCHOLINESTERASE ACTIVITY OF BALKAN CRESTED NEWT (TRITURUS IVANBURESCHI) LARVAE

Amphibians are the most threatened vertebrate class. Exposure to pesticides and climate change are considered pivotal factors in the global decline of their populations. Glyphosate-based formulations are the most widely used herbicides, but increasing evidence of their harmful effects, including oxidative stress in exposed organisms, has sparked a heated debate. Current climate prediction models assume a global temperature rise of 3 °C to 5 °C in the coming decades. In poikilotherms, any changes in ambient temperature are directly translated into changes in physiological and biochemical processes. Furthermore, elevated temperatures could intensify the toxic effects of pesticides present in the environment. The aim of this study was to examine the effects of low, environmentally realistic concentrations of glyphosate-based herbicides (30 µg/L active ingredient) and elevated temperature (optimal t1=19°C and increased t2=23°C) on glutathione content (GSH), antioxidant enzyme activities (SOD, CAT, GSH-Px, GR and GST), activity of acetylcholinesterase (AChE) and levels of oxidative damage (TBARS - lipid peroxidation and PC - protein carbonylation) in larvae of the Balkan crested newt (T. ivanbureschi). Our findings revealed that glyphosate had a significant effect on the activity of all antioxidative enzymes, with the exception of SOD. Herbicide and elevated temperature led to a significant increase in the activities of CAT, GSH-Px, GST, and GR, as well as GSH concentration. This response of the antioxidative defense system prevented oxidative damage to lipids and proteins. Glyphosate exhibited a neurotoxic effect by inhibiting AChE only at elevated temperatures, while no significant change occurred at the optimal temperature. The findings suggest the importance of examining the potentially harmful effects of glyphosate in different ecological contexts, such as an increase in average temperatures by several degrees predicted by future climate scenarios.

Svetlana G Despotović, Branka R Gavrilović, Tijana B Radovanović, Marko D Prokić, Tamara G Petrović, Maja Ajduković, Milena Cvijanović, Tijana Vučić, Zorana Milosavljević, Jelena P Gavrić

29.08.2024.

Professional paper

FATTY ACID PROFILES DIFFER BETWEEN HEALTHY AND MULTIPLE SCLEROSIS-DIAGNOSED ADULTS

Multiple sclerosis (MS) is a chronic, immune-mediated inflammatory disease of the central nervous system (CNS). Relapsing-remitting multiple sclerosis (RRMS) is the most common clinical subtype of MS. MS is characterized by demyelination and myelin is mainly composed of lipids. Lipids play many roles in the CNS including signaling, structural support, mediating inflammation, and membrane biogenesis. Omega-3 polyunsaturated fatty acids (PUFA) are central to maintaining health and they are present in a wide array of tissues with broad functions including the active component of phospholipid cell membranes and substrate for molecular signaling pathways. This study aimed to evaluate fatty acids (FA) profiles of patients with RRMS (n=30) compared to healthy people (n=20). Analysis of total lipids was performed from erythrocyte samples. The total lipid extracts from erythrocytes were prepared by adding chloroform/methanol (2:1, v/v) mixture containing butylated hydroxytoluene (0.05% BHT weight/volume). FA methyl esters were prepared by transmethylation with 3N HCl in methanol. FA profiles were determined by gas chromatography (GC). The content of individual FA was expressed as a percentage of the total FA. Results of this study revealed that total saturated fatty acids (SFA) are significantly higher in MS patients compared to controls. While total PUFAs, total n-3 PUFAs, and omega-3 index are statistically lower in MS patients. The n-6/n-3 ratio is significantly higher in MS patients compared to controls. Also, the AA/EPA ratio is significantly lower in the control group compared to MS patients. Conversely, the EPA/AA index is significantly reduced in MS patients. Omega-3 lipids, which have a protective role by preserving the blood-brain barrier, are significantly reduced in the erythrocytes of patients with MS. Increased n-3 PUFA and decreased SFA intake could counteract inflammation, energy storage and utilization imbalance and, overall state in patients with MS.

Slavica Ranković, Marija Takić, Jovana Kuveljić, Maja Bosković, Evica Dincić, Aleksandra Stanković, Maja Živković

29.08.2024.

Professional paper

PREDICTIVE VALUE OF TOTAL OXIDANT STATUS AND TOTAL ANTIOXIDANT STATUS IN NON-ALCOHOLIC FATTY LIVER DISEASE

According to global epidemiology, non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, affecting about a quarter of the adult population worldwide. NAFLD is characterised by the accumulation of triglycerides in hepatocytes (steatosis), which can progress to non-alcoholic steatohepatitis, a more severe form of NAFLD. Oxidative stress is closely linked to the disease progression due to the activation of inflammatory pathways. The aim of this study was to identify markers of redox status that could predict the risk of developing steatosis. The study included 179 participants who underwent ultrasound examination at University Medical Centers Zemun and Zvezdara. Participants were divided into two groups: 119 patients with steatosis and 60 apparently healthy controls (control group, CG). Biochemical markers as well as markers of redox status: total oxidant status (TOS) and total antioxidant status (TAS) were determined in serum spectrophotometrically on biochemical analysers. Univariate and multivariate binary logistic regression analyses were used to test the predictions of TOS and TAS for NAFLD. Patients had higher body mass index (P<0.001), glucose (P<0.001), uric acid (P<0.001), TOS (P=0.007), and TAS (P<0.001) levels compared to CG. Univariate binary regression analysis revealed significant predictive capability of TOS and TAS for NAFLD demonstrated by the following ORs: 1.104 (1.020-1.195) (P=0.014) and 1.003 (1.001-1.004) (P<0.001), respectively. After applying multivariate binary logistic regression analyses (adjustments were made for sex and BMI), TOS and TAS kept independent significant predictive capability for NAFLD, as demonstrated by the following ORs: 1.098 (1.009-1.195) (P=0.030) and 1.002 (1.000-1.003) (P=0.026), respectively. TOS and TAS are positively associated with the risk of developing NAFLD, independent of sex and BMI. Both markers are elevated, probably because increased oxidative activity requires a stronger antioxidant defence response, which should be confirmed by a follow-up study including more participants.

Sanja Erceg, Jelena Kotur-Stevuljević, Ratko Tomašević, Miloš Mitrović, Milica Mamić, Ana Ninić

29.08.2024.

Professional paper

ARTIFICIAL LIGHT DISRUPTS NATURAL DAY/NIGHT VARIATION IN ANTIOXIDANT SYSTEM OF TREE FROG (HYLA ARBOREA)

One of the adaptive features that organisms developed throughout their long natural history is the ability to change the activity of cells, tissues, and organs on a daily, 24-hour, basis. These cyclical changes are synchronized to the external environment through a light-dark regime and internal circadian clock. Daily recurring environmental changes are followed by variations in animal behavior and physiology, which include oscillations in neuroendocrine, metabolic, cardiovascular, and immune functions. By transforming the circadian periodicity of day, artificial light from anthropogenic sources might interfere with organisms leading to a disturbance in hormone levels and physiological stress. In this study, we investigated daily natural variations in the antioxidant system and the effects of artificial light on the redox balance in larvae of tree frogs. We compared antioxidant parameters in tadpoles from the natural day/night cycle (control) with ones exposed to artificial light at night (treatment). The antioxidant response was measured at four time points during 24h (morning, day, evening, and night). Our results showed that only GR activity did not display day/night changes nor was affected by night illumination. For GSH-Px and GST we reported changes in activity at different times of day that were in the same manner for both treatment and control. The highest values were in the morning compared to the other time points. Variation during 24h was also observed for SOD, CAT and GSH. However, exposure to night light affected the pattern and intensity of these parameters compared to the control group. Overall our study suggests that daily differences in metabolic activity can result in variations in the antioxidant system and that the presence of artificial light affects these changes. The disrupted natural rhythm of the antioxidant response may further reflect on other physiological processes and lead to a state of oxidative stress.

Marko D Prokić, Jelena P Gavrić, Svetlana G Despotović, Branka R Gavrilović, Tijana B Radovanović, Ana Kijanović, Marko Mirč, Tanja Vukov, Nevena Đukić, Nataša Tomašević Kolarov, Tamara G Petrović

29.08.2024.

Professional paper

PROGNOSTIC POTENTIAL OF LEUKOCYTE TELOMERE LENGTH AND PARAOXONASE 1 ACTIVITY IN SMALL CELL LUNG CANCER

Small cell lung cancer (SCLC) is the leading cause of cancer-related deaths worldwide and is characterized by rapid growth, early metastasis, and high mortality rates. This study investigated the prognostic potential of leukocyte telomere length (LTL) and paraoxonase 1 (PON1) activity in 60 SCLC patients treated with a cisplatin/etoposide (PE) regimen. Patients were observed at baseline, after 2 cycles, and after 4 cycles of chemotherapy. The primary objective was to evaluate the prognostic potential of these biomarkers for patient survival. LTL was measured from isolated genomic DNA using real-time quantitative polymerase chain reaction (RTq-PCR), while PON1 activity was determined using a spectrophotometric method. A Kaplan-Meier survival analysis was performed with cut-off values below the 25th percentile for LTL and PON1 activity to determine their prognostic power for overall survival. The analysis revealed that both LTL and PON1 are significant predictors of patient survival, suggesting that patients with levels below the 25th percentile have a higher risk of death (Log Rank = 3.956, p = 0.047; Log Rank = 3.834, p = 0.050, respectively). Telomeres, the protective caps at the ends of chromosomes, shorten with each cell division and reflect cell aging and genomic stability. Shorter telomere lengths in leukocytes have been associated with a poorer prognosis and lower survival rates in SCLC patients. Similarly, reduced PON1 activity is associated with increased oxidative stress, which contributes to cancer progression and poorer clinical outcomes. Monitoring PON1 activity could help in assessing patient prognosis and adjusting treatment strategies. These findings suggest that LTL and PON1 activity have significant prognostic value in SCLC and serve as useful indicators for identifying high-risk patients and guiding treatment decisions to improve outcomes.

Azra Guzonjić, Dragana Jovanović, Ivana Simić, Vesna Ćeriman Krstić, Natalija Samardzić, Barbara Ostanek, Janja Marc, Miron Sopić, Jelena Kotur Stevuljević

29.08.2024.

Professional paper

DIFFERENT DEGREES OF OXIDATION CAUSE DIFFERENT CELL TRANSFORMATIONS AND FORMATION OF MICROPARTICLES

Oxidative stress (OS) has a significant impact on the lifespan and physical fitness of living organisms. It is commonly associated with ageing and can lead to changes in the functionality of red blood cells (RBCs). The precise mechanisms underlying these changes are not fully understood. Unlike mammals, avian RBCs have a nucleus and functional mitochondria that regulate the cellular response to oxidative stress. In this study, we examined the effects of OS on red blood cells from adult female quail (Coturnix japonica, n=12). We used flow cytometry to analyze the formation of OS-induced microparticles and RBC transformation. We also evaluated band 3 clustering and phosphatidylserine externalization at the cell surface using eosin-5-maleimide and Annexin-V fluorescent probes, respectively. In addition, we analyzed band 3 clustering using confocal microscopy. We used a laser diffraction-based method to analyze cell deformability, and we characterized hemoglobin species spectrophotometrically. We found that OS caused band 3 clustering, microparticle formation, and phosphatidylserine release onto the cell membrane. The microparticles formed under the influence of oxidants differed from those formed under the influence of A23187 (calcium ionophore). The rate of microparticle formation and the onset of osmotic rigidity depended on the oxidant concentration. Erythrocyte-derived microparticles contained hemoglobin oxidized to hemichrome (HbChr). Overall, these findings demonstrate that avian erythrocytes undergo different processes during oxidative stress, depending on the level of oxidation. These differences are due to variations in cellular transformations and the formation of different types of microparticles. This research was supported by the Russian Fund for Basic Researches (grant no. 23-15-00142)

Anastasiya Volkova, Irina Iskortseva, Diana Mikhailova, Aleksandra Andreyeva, Igor Mindukshev

29.08.2024.

Professional paper

RELATIONSHIP BETWEEN PLASMA/ERYTHROCYTES GLUTATHIONE RATIO AND HEALTH STATUS

Considering the crucial antioxidant role of glutathione (GSH) in cells, its assessment is useful for both healthy populations and in different diseases. It is usually measured either in erythrocytes or in plasma, while it is unknown whether the distribution of GSH between these compartments depends on a presence of a disease, thus affecting the results. Therefore, our aim was to investigate the relationship between GSH in plasma and erythrocytes of healthy and diseased subjects. The study included 60 participants, 25 healthy subjects, and 35 patients with different diseases (cancer, heart failure, kidney diseases, chronic fatigue, sarcoidosis, Lyme disease). GSH levels were determined in plasma and erythrocytes using spectrophotometric method with Ellman’s reagent. GSH plasma/erythrocytes ratio between two groups was compared by Mann-Whitney U test and the results are presented as median (interquartile range). The median value of plasma/erythrocytes ratio for healthy subjects was 3.79 (3.32-5.71), and for patients, it was 27.54 (1.53-54.76). This ratio was significantly higher in the group of patients compared to healthy participants (P=0.018). Our results indicate a redistribution of GSH from erythrocytes to plasma in the presence of different diseases. The fact that this preliminary study points out an association of health status with plasma/erythrocytes GSH ratio, regardless of the heterogeneity of a patient group, encourages further research in this direction.

Ana Ružanović, Minja Derikonjić, Radmila Ristić, Marija Vasić, Aleksandra Drašković, Branislav Milovanović, Iva Perović-Blagojević, Strahinja Đurić, Jelena Kotur-Stevuljević

29.08.2024.

Professional paper

THE ASSOCIATION OF TUMOR SIZE AND THE PRESENCE OF LYMPH NODE METASTASES IN BREAST CANCER PATIENTS

Breast cancer is one of the most common malignant diseases in women worldwide. Since the involvement of axillary lymph node metastases is related to the poor prognosis of these patients, the objective of our study was to investigate the association between breast tumor size and the presence of axillary lymph node metastases. Our research was performed at the Institute of Oncology of Vojvodina in Sremska Kamenica. The study consisted of 72 women diagnosed with breast cancer aged between 29 and 84 years (average age: 59.04±10.87 years) whose breast tumor was surgically removed at the Institute of Oncology of Vojvodina. Patients who received preoperative chemo- or radiotherapy were excluded from the study. The data concerning breast tumor size and the presence of axillary lymph nodes in these women was obtained from the reports of Department of Pathoanatomical Diagnostics of the Institute of Oncology of Vojvodina. The results of our study indicated to positive, statistically significant moderate correlation between the size of breast tumor and the presence of axillary lymph node metastases (r=0.32, p=0.01). Receiver operating curve (ROC) analysis notified that cut-off value of breast tumor size for the presence of axillary lymph node metastasis was 22.5 mm (AUC=0.70, p=0.01). In our investigation, women with breast tumor size of 22.5 mm or larger were predisposed to the presence of axillary lymph node metastases.

This research was supported by the Science Fund of the Republic of Serbia, #7750238, Exploring new avenues in breast cancer research: Redox and metabolic reprogramming of cancer and associated adipose tissue - REFRAME.

Mirjana Udicki, Zorka Drvendžija, Biljana Srdić Galić, Tamara Zakić, Aleksandra Janković, Aleksandra Korać, Bato Korać

29.08.2024.

Professional paper

IMPACT OF SULFUR AMINO ACIDS SUPPLEMENTATION ON PERFORMANCE, OXIDATIVE STRESS, AND LIVER HISTOLOGY IN FEED-RESTRICTED INSHAS COCKERELS

A 60-day experiment was conducted to investigate the impact of dietary sulfur amino acids (AA) on altered haemato-biochemical and redox parameters of Inshas cockerel chicks raised under restricted feeding. Male Inshas strain chickens were divided into five groups, each with five replicates of eight birds. The control group received the full National Research Council (NRC) requirements (100%). The other groups received diets meeting 90% of NRC requirements: 90% NRC; 90% NRC+Methionine; 90% NRC+Cysteine; and 90% NRC+both Methionine and Cysteine (AA-mix). AA supplementation improved growth performance compared to the control group. The birds that were given a combination of AA supplementation exhibited the highest body weight and carcass weight compared to other groups. AA supplementation improves blood physiological characteristics by reducing damage caused by feed restriction conditions. Serum parameters, including aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, alkaline phosphatase, gamma-glutamyl transpeptidase, and total protein concentration, showed decreased levels. Treatment with mixed AA maintained urea and uric acid concentrations at a level similar to the control group. Remarkably, a combination of AA treatments reduced the negative effects of feed restriction on young male chickens by enhancing the overall antioxidant capacity and activity of antioxidant enzymes in liver tissue (glutathione S-transferase, total superoxide dismutase, glutathione peroxidase, and amount of total glutathione), and decreased the malondialdehyde concentration. Feed restriction impacted liver histological structure, where hepatocytes were susceptible to feed restriction and included numerous cytoplasmic vacuoles, congested blood vesicles, lymphocytic infiltration, and pyknotic nuclei in treated cockerels. AA therapy restored most hepatic histological abnormalities. The findings suggest that AA supplementation significantly mitigated the adverse effects of feed restriction by improving haemato-biochemical parameters and hepatic redox status.

Acknowledgement: The authors extend their appreciation to the Department of Animal and Poultry Production, Faculty of Agriculture, Minia University, Egypt.

Hamada Elwan, Hemdan Mahmoud, Abdelhameed Mohamed, Marija D. Milošević, Mohamed Mohany, Salim S. Al-Rejaie, Shaaban S. Elnesr

29.08.2024.

Professional paper

EFFECT OF SUCCINATE DEHYDROGENASE DEFICIENCY ON MITOCHONDRIAL FUNCTION

Succinate dehydrogenase (SDH) connects the tricarboxylic acid (TCA) cycle and the respiratory chain. Mutations in SDH subunits have been associated with tumorigenesis and mitochondrial disease. In this project, we focused on subunit A of SDH (SDHA), primarily associated with inherited mitochondrial disease, and investigated the consequences of its loss or re-expression of mutant variants in HEK cells (SDHA KO). Lack of SDHA led to a downregulation of all SDH subunits and a secondary downregulation of the majority of mitochondrial complex I and IV subunits. Cellular respiratory capacity was severely decreased in the model, SDH-dependent respiration completely abolished and complex I-dependent respiration attenuated, reflecting the downregulation of respiratory chain complexes in general. Finally, the NAD+/NADH ratio was increased in SDHA KO, indicating complex rearrangement of the TCA. It resulted in higher glycolytic activity and lipid accumulation.

Supported by Czech Science Foundation (21-18993S), Grant Agency of Charles University (283423) and Czech Health Research Council (NU22-01-00499).

Maria Jose Saucedo-Rodriguez, Petr Pecina, Kristýna Čunátová, Marek Vrbacký, Tomáš Čajka, Ondrej Kuda, Tomáš Mráček, Alena Pecinová

29.08.2024.

Professional paper

MEDITERRANEAN MUSSELS (MYTILUS GALLOPROVINCIALIS) UNDER SALINITY STRESS: EFFECTS ON ANTIOXIDANT CAPACITY

Estuarine and intertidal bivalve mollusks frequently experience salinity fluctuations that may drive oxidative stress (OS) in the organism. Here we investigated OS markers and histopathological changes in gills and hemolymph of Mediterranean mussels Mytilus galloprovincialis acclimated to a wide range of salinities (6, 10, 14, 24, and 30 ‰). Mussels were captured at the shellfish farm with the salinity of 18% and then acclimated to hypo- and hypersaline conditions in the laboratory at the speed of 1.5±0.5‰ per day. Indicators of redox balance in hemocytes (intracellular reactive oxygen species (ROS) levels, DNA damage) and gills (thiobarbituric acid reactive substances (TBARS), protein carbonyls (PC), activity of catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) were measured. The results revealed induction of OS in tissues and cells of mussels for both experimental increase and decrease salinity modeling. Hemocytes showed higher sensitivity to oxidative damage from salinity stress compared to gills, as DNA damage and elevated ROS levels were observed in all experimental groups except 14‰. A decrease in environmental salinity to 10 ‰ was likely within the physiological norm for mussels, as minor oxidative damage was noted. At a salinity of 6 ‰, the most significant signs of redox imbalance, including DNA damage, increased ROS production levels in hemocytes, and suppressed activity of SOD in gills were observed, along with elevated PC levels. An increase in environmental salinity up to 30 ‰ led to the enhancement of the activity of antioxidant enzymes in the gills, which may be attributed to the high capacity of the antioxidant system in this organ. The study provides new insights into the effects of salinity stress on the tissue and cellular redox balance of bivalves, which is crucial for better understanding the potential consequences of the global transformation of coastal ecosystems.

Aleksandra Yu Andreyeva, Olga L Gostyukhina, Tatiana B Sigacheva, Anastasia A Tkachuk, Maria S Podolskaya, Elina S Chelebieva, Ekaterina S. Kladchenko

29.08.2024.

Professional paper

UNCOUPLING PROTEIN 1 EXPRESSION IN LIPOMA TISSUE AND LIPOMA-DERIVED STEM CELLS

Mechanisms and factors that lead to the formation of lipomas, benign tumors of adipose tissue, are still insufficiently elucidated. Mesenchymal stem cells (MSCs) isolated from lipomas have some similar characteristics to MSCs isolated from white adipose tissue but differ at the molecular level and in their differentiation potential. Considering histological appearance of lipomas, it is not clear to what extent lipomas share common characteristics with other adipose tissue type, brown adipose tissue. Therefore, the aim of this study was to examine the level of uncoupling protein 1 (UCP1), a marker of brown adipose tissue, expression in lipoma tissue as well as in MSCs isolated from lipomas, i.e. lipoma-derived mesenchymal stem cells (LDSCs). LDSCs were grown in standard cell culture conditions and subjected to adipogenic differentiation. UCP1 expression was examined at the RNA level, using Real-Time PCR, and at the protein level, using immunohistochemistry and immunogold staining. Expression of UCP1 in lipoma tissue and LDSCs was compared with the expression of UCP1 in subcutaneous white adipose tissue (scWAT) and adipose-derived mesenchymal stem cells (ADSCs) grown and differentiated in the same cell culture conditions. Differences were observed in UCP1 expression at both RNA and protein levels in lipomas compared to scWAT directing the future research towards the potential of browning mechanisms of adipose tissue involved in lipoma tissue formation.

This research was financially supported by the Science Fund of the Republic of Serbia, PROMIS, #6066747, WARMED and the Ministry of Science, Technological Development and Innovations of the Republic of Serbia, Contract No. 451-03-65/2024-03/200113.

Sanja Stojanovic, Aleksandra Korac, Stevo Najman, Aleksandra Jankovic

29.08.2024.

Professional paper

APPLICATION OF FREE RADICAL SCAVENGERS IN HUMAN LUNG CANCER CELLS IRRADIATED WITH PHOTONS AND CARBON IONS

Ionising radiation damages DNA directly, or indirectly, causing water radiolysis and formation of free radicals. Indirect irradiation effects could be diminished in the presence of free radical scavengers, such as dimethyl sulfoxide (DMSO). Such conditions would allow the evaluation of direct radiation effects and provide a better understanding of cellular response to irradiation-induced damages. The goal of this study was to investigate the effects of low (γ-rays) and high linear energy transfer (LET) radiation (carbon ions) in non-small lung cancer cells HTB177. Cells were pre-treated with DMSO and irradiated with 60Co γ-rays and 62 MeV/u carbon ions, with doses ranging from 1-5 Gy. Results obtained by clonogenic survival and γ-H2AX foci assay showed that DMSO increased cell survival and decreased number of DNA damages, which points to radioprotective effect of DMSO. The contribution of direct and indirect radiation effects was estimated by the degree of protection (DP) in presence of DMSO. The values of DP rose in a concentration-dependent manner in all irradiated samples. In cells irradiated with γ-rays, 35% of damages were caused directly, while 65% of lesions could be attributed to indirect radiation actions. In presence of carbon ions, contribution of direct effects was 49%, while 51% of damage resulted from indirect radiation effects, showing that free radicals attain an important role in both low and high LET irradiations. The obtained results showed that DMSO can be used as a free radical scavenger to examine the direct and indirect effects on human cancer cells. The numerical Monte Carlo simulations allow modelling of direct and indirect irradiation actions in cancer cells with photons and hadrons. Therefore, this data will be used for validation and further improvement of numerical simulations in comparison to the data collected on different cell lines and irradiation energies, with the goal to improve therapeutic protocols.

Vladana Petković, Otilija Keta, Miloš Đorđević, Giada Petringa, Pablo Cirrone, Ivan Petrović, Aleksandra Ristić Fira

29.08.2024.

Professional paper

REDOX METABOLIC CHANGES IN TUMOR AND ASSOCIATED ADIPOSE TISSUE OF COLON CANCER PATIENTS

Colorectal cancer presents a significant global health challenge, with a high mortality rate. It is the third most commonly diagnosed cancer and is therefore a major cause for concern. The development of colorectal cancer is multifaceted, involving a combination of genetic predispositions and lifestyle factors. The redox and metabolic states may influence the intricate process of colon cancer development. To gain a deeper understanding of the redox-metabolic profiles associated with colon cancer, a human study was conducted. In biopsies from patients with colon cancer, the antioxidant status: copper, zinc superoxide dismutase (CuZnSOD), manganese superoxide dismutase (MnSOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutamate-cysteine ligase (GCL), thioredoxin (Trx) and lactate metabolism were examined in tumor and unaffected colon tissue (remote 15-20 cm) as well as in adipose tissue: proximal (near the tumour tissue), distal (remote 6 cm) and unaffected (remote over 6 cm). The protein levels of CuZnSOD, MnSOD, GSH-Px, and Trx are increased in the tumor tissue compared to the unaffected colon tissue. In addition, the expression of the lactate dehydrogenase (LDH) A isoform, the total activity of LDH and the lactate concentration are higher in transformed tumor tissue than in normal colon tissue. On the other hand, lactate concentration increases and several AD components (CuZnSOD, MnSOD, CAT, GSH-Px, GCL and Trx) decrease in adipose tissue with tumor proximity. Shifts in redox and lactate metabolism in tumor tissue associated with spatial changes in lactate and antioxidant enzymes gradients in adjacent adipose tissue clearly indicate a local redox metabolic interaction between tumor and tumor-associated adipose tissue in shaping the malignant phenotype in human colorectal cancer.

Jelena Jevtic, Tamara Zakic, Aleksandra Korac, Sanja Milenkovic, Dejan Stevanovic, Aleksandra Jankovic, Bato Korac

29.08.2024.

Professional paper

IMPACT OF HYPOTHYROIDISM ON CuZnSOD AND MnSOD DURING SPERMATOGENESIS IN RATS

Thyroid hormones play an important role in both testis development and spermatogenesis. While hypothyroidism has been known to generally induce metabolic suppression, lower respiration rate, and reduce free radical formation, recent studies reported an increased production of reactive oxygen species (ROS). First line of antioxidant defense in testes is comprised of two isoforms of superoxide dismutase (SOD), CuZnSOD and MnSOD differently localised in cell. This study aimed to investigate the effects of hypothyroidism on the expression, localisation, and activity of these two SOD isoforms during spermatogenesis. Hypothyroidism was induced in two-month-old male Wistar rats by 0.04% methimazole in drinking water for 7, 15, and 21 days, while euthyroid control group drank tap water. CuZnSOD protein expression was decreased after 15 and 21 days while its activity was decreased by 40% in all examined time points of methimazole treatment in comparison to euthyroid control. At the same time, neither MnSOD protein expression nor its activity was changed by treatment. However, cell and stage-specific CuZnSOD and MnSOD immunoexpression in the rat testes were changed in hypothyroidism and may contribute to the altered spermatic characteristics. Our results suggest that changes in CuZnSOD and MnSOD expression play role in redox disbalance leading to hypothyroidism-induced maturation arrest of spermatogenesis.

Isidora Protic, Marija Aleksic, Igor Golic, Aleksandra Jankovic, Bato Korac, Aleksandra Korac

29.08.2024.

Professional paper

CHARACTERIZING THE BRAIN-HEART-VESSEL AXIS IN AIRCRAFT NOISE-INDUCED NEUROPSYCHIATRIC AND CARDIOVASCULAR COMPLICATIONS

The World Health Organization (WHO) estimates that noise pollution leads to the loss of 1.6 million healthy life years annually in Western Europe alone, primarily due to night-time noise exposure which disrupts sleep and triggers stress responses. This study investigates the adverse health effects of aircraft noise on the brain-heart-vessel axis, combining cardiovascular and neuropsychiatric approaches. We aim to characterize the functional and biochemical consequences of both short-term and long-term noise exposure utilizing an established mouse model. Behavioural changes in exposed mice, including cognition, anxiety, depression, and social behaviour were assessed alongside cardiovascular parameters such as blood pressure, endothelial function tests, and analyses of oxidative stress and inflammation markers. Short-term noise exposure did not lead to any significant differences in the behaviour of the noise-exposed mice, whereas long-term noise-exposure leads to reduced social interaction and working memory as behavioural markers of depression. Functional cardiovascular parameters point to hypertension and impaired endothelial function in both short-term and long-term noise exposure, as well as oxidative stress and inflammation. These findings underscore previously reported cardiovascular impact of noise exposure while adding the suspected behavioural changes and metabolic markers of the affected brain-heart axis. The observed behavioural changes and cardiovascular impairments emphasize the complex interplay between environmental stressors and health, suggesting that long-term noise exposure can have profound effects on both mental and cardiovascular health. This study provides a comprehensive framework for future research aimed at reducing the adverse effects of noise pollution on the brain-heart-vessel axis.

Ivana Kuntić, Leonardo Nardi, Guilherme Horta, Marin Kuntić, Matthias Oelze, Arijan Valar, Jiayin Zheng, Dominika Mihalikova, Lea Strohm, Henning Ubbens, Michael Schmeißer, Andreas Daiber

29.08.2024.

Professional paper

ADJUVANT TREATMENT WITH POLYPHENOLS REDUCES OXIDATIVE STRESS PARAMETERS IN IMATINIB TREATED PATIENTS WITH CHRONIC MYELOID LEUKEMIA

Imatinib, a tyrosine kinase inhibitor (TKI) is used as a standard treatment in chronic myeloid leukemia (CML) patients. Increased levels of BCR-ABL1 expression in CML cells are associated with oxidative stress induction due to overproduction of reactive oxygen species (ROS) or by deficient antioxidant system, disease progression, and imatinib resistance. Current scientific research confirms that oxidative stress is involved in CML pathogenesis and response to TKI treatment. Moreover, recent findings suggest that the antioxidant properties of some natural compounds can provide benefits to patients with CML. To determine the effect of adjuvant treatment with polyphenols on the oxidative stress markers in imatinib-treated CML patients. 40 CML patients at the University Clinic of Hematology, Skopje, who received imatinib longer than 1 month were included in the study. 20 patients were additionally treated with Aronia melanocarpa extract and 20 patients received only imatinib (control group). Besides the regular clinical laboratory analysis for these patients, total antioxidant power (PAT) and plasma peroxides (d-ROMs) were measured at initial visit and after 21 and 42 days of treatment using FRAS5 analytical photometric system and the oxidative stress index (OSI) was automatically calculated. Oxidative stress parameters (d-ROM and OSI) were significantly higher at initial visit in both groups. In group of patients who received adjuvant polyphenols values for d-ROM and OSI were significantly lower after 21 and 42 days of treatment (p<0.05). Also, total antioxidant capacity (PAT) was significantly higher after 21 and 42 days of treatment initiation in comparison with the pretreatment values. In the control group, no significant differences were obtained between investigated parameters at any time of measurement. Adjuvant treatment with Aronia melanocarpa extract after 21 and 42 days led to significant reduction of oxidative stress parameters in patients with CML treated with imatinib. 

Dragica Zendelovska, Marija Petrushevska, Bojan Labachevski, Marija Popova-Labachevska, Emilija Atanasovska

29.08.2024.

Professional paper

THE ROLE OF MACROPHAGE MIGRATION INHIBITORY FACTOR IN LIVER INFLAMMATION, OXIDATIVE STRESS, AND APOPTOSIS IN MICE ON A FRUCTOSE DIET

Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine that plays an essential role in the inflammatory response and various other biological effects such as activation of apoptosis and oxidative stress. Fructose-enriched diets have previously been associated with the development of low-grade inflammation leading to metabolic stress. The aim of the present study was to investigate the combined effects of deletion of the Mif gene and a 9-week 20% fructose-enriched diet on metabolic inflammation, apoptosis, and oxidative stress in the liver of wild-type (WT) and Mif knockout (MIF−/−) male C57Bl/6J mice. We analyzed liver histology and expression of pro-inflammatory genes: Tumor necrosis factor (TNF), interleukin 1β (IL-1β), and IL-6. Antioxidant activity was estimated by the protein levels of antioxidant enzymes catalase (CAT), superoxide dismutase (SOD1), mitochondrial MnSOD (SOD2), glutathione reductase (GR) and glutathione peroxidase (GPX). The results showed that antioxidant protection was activated in the liver of MIF-deficient mice. Increased hepatic expression of the cytokines IL-6 and IL-1β was observed in the same animals. Histologic analysis confirmed the presence of apoptosis, inflammation, enlarged Kupffer cells, and regenerative changes, such as binucleated hepatocytes, anisonucleosis, and anisocytosis. In addition, confluent and focal necrosis was observed in the liver of MIF−/− mice, which was even more pronounced in the animals consuming fructose. In conclusion, MIF may play a protective role in metabolic stress, as inflammation, oxidative stress, apoptotic and necrotic changes occur in the liver in its absence.

Ljupka Gligorovska, Ana Teofilovic, Milos Vrataric, Natasa Velickovic, Danijela Vojnovic Milutinovic, Sanja Kovacevic, Ana Djordjevic

29.08.2024.

Professional paper

THE ROLE OF NRF2-DEPENDENT METABOLIC REPROGRAMMING OF BROWN ADIPOSE TISSUE IN ORTHOTOPIC BREAST CANCER MODEL

Breast cancer is characterized by specific metabolic changes that support tumorigenesis, highlighting the emerging appreciation of cancer as a metabolic disease. These metabolic changes are simultaneous with redox reprogramming with nuclear factor erythroid 2-related factor 2 (Nrf2) representing their master integrator. Given that interscapular brown adipose tissue (IBAT) influences whole-body metabolism, our goal was to investigate the redox-metabolic crosstalk between the tumor and the host at the systemic level by exploring Nrf2-driven metabolic changes that occur in IBAT in the orthotopic model of breast cancer in wild-type (WT) and mice lacking functional Nrf2 (Nrf2KO). We analyzed the protein expression of key enzymes involved in glucose and lipid metabolism in control groups and at different points during tumor growth (10 mg, 50 mg, 100 mg, 200 mg, and 400 mg). In both WT and Nrf2KO mice, the results indicated a transient induction of hexokinase 2 expression during the early phase of tumor growth (<100 mg). Accordingly, pyruvate dehydrogenase expression followed the same profile. In Nrf2KO mice, a general decline in glyceraldehyde 3-phosphate dehydrogenase, phosphofructokinase-1, and glucose-6-phosphate dehydrogenase expression was detected during the late phase of tumor growth (>100 mg). Since no changes in WT mice occurred, these findings are considered Nrf2-dependent. Concomitantly, a decrease in protein expression of fatty acid synthase and acetyl-CoA carboxylase in Nrf2KO mice was observed. These observations correspond to decreased levels of 5'-AMP-activated protein kinase and hypoxia-inducible factor 1 during the late-phase (>100 mg) of tumor growth in Nrf2KO mice which suggests their involvement in transcriptional regulation. Our results revealed that IBAT metabolism responds to tumor growth and underscored that this communication is Nrf2-dependent giving implications for further understanding of breast cancer in the light of systemic metabolic disease.

This research was supported by the Science Fund of the Republic of Serbia, #7750238, Exploring new avenues in breast cancer research: Redox and metabolic reprogramming of cancer and associated adipose tissue - REFRAME.

Maja Vukobratovic, Strahinja Djuric, Jelena Jevtic, Tamara Zakic, Aleksandra Korac, Aleksandra Jankovic, Bato Korac

29.08.2024.

Professional paper

EFFECTS OF CHRONIC COLD EXPOSURE ON ANTIOXIDANT DEFENSE IN BROWN ADIPOSE TISSUE AND LIVER OF AGED RATS

Aging is a natural process characterized by a decline in organic structure-function and an increase in mortality over time. While many exogenous and endogenous factors contribute to aging, the long-term effects of low environmental temperature have been poorly described. To address this, our study compared 24-month-old male Mill Hill hybrid hooded rats raised at a standard temperature of 22±1°C with age-matched rats that were kept in a cold room (4±1°C) from the age of 6 to 24 months. 3- and 6-month-old rats raised at 22±1°C were included as room temperature controls. We examined two metabolically active organs, interscapular brown adipose tissue (iBAT) and liver. It was found that 24-month-old rats chronically exposed to cold exhibit increased food consumption, which may be attributed to a higher metabolic demand. Chronic exposure of aged rats to low environmental temperature led to an increase in iBAT relative mass, total glutathione (GSH) content, and antioxidant defense (AD) enzyme activity: CuZn superoxide dismutase, Mn superoxide dismutase, catalase, glutathione peroxidase, and thioredoxin reductase. Respirometric analysis further demonstrated an increase in mitochondrial uncoupling in iBAT in 24-month-old rats kept at 4±1°C. Conversely, there was no change of the same parameters in the liver, which maintained consistent AD enzyme activity and GSH content across all experimental groups. Our study confirms that iBAT of aged rats remains responsive to stimulation by low environmental temperature, supporting thermogenic processes through uncoupling and a robust increase in the AD system. These results highlight tissue-specific effects of chronic cold exposure on aged rats underlying acclimation-driven physiological changes.

Strahinja Djuric, Tamara Zakic, Aleksandra Korac, Bato Korac, Aleksandra Jankovic

29.08.2024.

Professional paper

VITAMIN MISUSE DURING THE COVID-19 PANDEMIC – SINGLE CENTER EXPERIENCE

The global pandemic crisis affected almost every society and economy, challenged almost every health system worldwide. Above all, governments and non-governmental organizations had to fight the misinformation and conspiracy theories placed by the social and mass media. All of this had a profound impact on the public in terms of vaccine safety and the advantages of vitamin use in fighting the virus. This fear has opened doors to alternative medicines such as supplements (vitamins, minerals, herbal products, oils) that may have profound effects on the immune system. To determine the pattern of use of supplements during the pandemic in healthy individuals who tested negative for SARS-CoV-2. The 33 healthy individuals tested negative for SARS-CoV-2 in the pandemic period were included (Group 1). Total antioxidant power, iron-reducing (PAT), and plasma peroxides (d-ROMs) were measured using FRAS5 analytical photometric system and are reported in equivalents of ascorbic acid and H2O2, respectively. The oxidative stress index (OSI) was automatically calculated by the software. The obtained values were compared with 30 healthy individuals analyzed prior to the pandemic (Group 2). The mean values for oxidative stress parameters in Group 1 vs Group 2 were: d-ROMs 418 vs 266 U. Carr, PAT 3862 vs 2554 U. Carr, and OSI 111 vs 36. In all comparisons, a statistically significant difference was obtained (p<0.05, t-test). Individuals belonging to Group 1 had reported that they have consumed daily doses of Zinc (30 mg), Vitamin C (at least 1000 mg) and Vitamin D (at least 2000 IU) in a period of >1 month. Several of them have also used Isoprinosine, magnesium, and selenium. Uncontrolled intake of supplements can have a profound effect on the pro- and antioxidant balance resulting in interruption of the phycological balance and leading to increased oxidative stress index in otherwise healthy individuals. 

Marija Petrushevska, Dragica Zendelovska, Emilija Atanasovska

29.08.2024.

Professional paper

NEUROPEPTIDE Y DISRUPTS REDOX BALANCE IN HUMAN EXTRAVILLOUS TROPHOBLASTS

Human extravillous trophoblasts play a key role in implantation, placentation, and successful pregnancy outcomes due to their ability to migrate and invade through the uterine spiral arteries. Abnormalities in the trophoblasts' migratory and invasive abilities may result in insufficient remodeling of the uterine spiral arteries. This leads to the development of preeclampsia, a syndrome in pregnancy. Neuropeptide Y (NPY) is a sympathetic neurotransmitter that plays a significant role in the adaptive stress response as well as in the regulation of body energy balance. This study was designed with the aim of investigating whether preeclampsia is associated with NPY-induced disruption of trophoblast migration and redox balance. For this purpose, the concentration of NPY was determined in the plasma of 20 healthy and 20 preeclamptic pregnant women. The obtained results demonstrated that in preeclampsia, the concentration of NPY is significantly lower (190 pg/mL) than in a healthy pregnancy (260 pg/mL). After that, NPY in concentrations of 190 pg/mL and 260 pg/mL was used to treat the human extravillous trophoblast cell line HTR-8/SVneo for ten weeks. The effect of NPY on trophoblast proliferation was determined by counting cells during each passage. After the end of the treatment, the effect of NPY on migration and intracellular concentrations of superoxide anion radical (O2.-), hydrogen peroxide (H2O2), and nitric oxide (NO) were examined. The obtained results show that NPY induces changes in trophoblast proliferation and reduces their migration at both applied doses. In addition, both doses of NPY induce a decrease in intracellular concentrations of O2.-, H2O2, and NO. The NPY concentration of 190 pg/mL significantly decreased O2.- in trophoblasts in comparison to the concentration of 260 pg/mL. This study demonstrates that NPY affects the migration and redox balance regulation of trophoblasts. It also disrupts the trophoblast redox balance at a level characteristic of preeclamptic pregnancy.

Nejla H Zupic, Zana C Dolicanin, Natasa Z Djordjevic