The effect of long-term food restriction on te expression of glucocorticoid receptor in the rat forebrain during aging

Dugotrajna restrikcija hrane produžava životni vek i odlaže pojavu mnogih bolesti koje se javljaju sa starenjem. Brojni literaturni podaci ukazuju da kod životinja kojima je unos hrane smanjen izostaje karakterističan starosno-zavistan pad u kognitivnim funkcijama, međutim, mehanizam ovakvog neuroprotektivnog dejstva restrikcije hrane nije u potpunosti razjašnjen. U isto vreme, kod životinja na dugotrajnoj restrikciji hrane se povećava nivo kortikosterona u plazmi što ukazuje da ovaj tretman deluje kao blagi stresor. Do sada nije ispitivano do kakvih promena u signalnom putu glukokortikoida dovodi smanjeni unos hrane tokom starenja u mozgu. Centralno polje istraživanja procesa starenja neizbežno podrazumeva ispitivanje promena do kojih dolazi u korteksu i hipokampusu, strukturama mozga koje su ključne za kognitivne funkcije. Sa druge strane, iste strukture učestvuju u regulaciji HHA ose kao važni regioni delovanja negativne povratne sprege. Cilj doktorske disertacije je da se ispita uloga signalnog puta glukokortikoida u korteksu i hipokampusu pacova tokom starenja i pod uticajem dugotrajne restrikcije hrane. Eksperimentalne životinje (mužjaci pacova soja Wistar) starosti 6 meseci su podeljene u dve grupe. Prva grupa, označena kao ad libitum (AL), je imala neograničen pristup hrani, dok je druga grupa (označena kao DR) podvrgnuta režimu redukovane ishrane koji je podrazumevao dobijanje 100% dnevnog unosa hrane AL životinja svakog drugog dana. Životinje su analizirane kada su dostigle starost od 18 i 24 meseca. Životinje stare 6 meseci su predstavljale kontrolnu grupu. Glukokortikoidna signalizacija u ispitivanim strukturama je praćena na prereceptorskom nivou, kao i na nivou ekspresije i aktivacije glukokortikoidnog receptora primenom imunoesej, imunoblot i PCR metoda, kao i imunohistohemijske analize. Rezultati doktorske disertacije pokazuju da tokom starenja dolazi do povećanja koncentracije kortikosterona u korteksu pacova, dok dugotrajna restrikcija hrane povećava nivo kortikosterona u obe ispitivane strukture. Utvrđeno je da nivo ključnog enzima koji u moždanom tkivu reguliše dostupnost kortikosterona za receptore, 11β-HSD1, raste u hipokampusu pacova koji imaju neograničen pristup hrani. Tretman dugotrajnom restrikcijom hrane dovodi do povećanja nivoa 11β-HSD1 u korteksu, dok u hipokampusu izostaje efekat na nivo ovog enzima...Moderate restriction in food intake (dietary restriction, DR) extends the life-span and delays the onset of many age-related diseases. In addition, food-restricted animals exhibit attenuated cognitive deficits during aging as they perform better in learning and memory tasks than their ad libitum fed counterparts. At the same time, the animals on chronic food restriction have elevated levels of plasma corticosterone, which implies that this treatment could be considered as a mild stressor. So far, there are no literature data regarding the effects of food restriction on glucocorticoid signaling in the brain during aging and the mechanisms by which DR exhibits its neuroprotective effects are poorly understood. Two brain regions of interest are cortex and hippocampus, regions particularly prone to age-related changes. The same regions are also involved in cognition and regulation of the hypothalamic–pituitary–adrenal (HPA) axis activity. The aim of the present study was to evaluate the effect of long-term food restriction on glucocorticoid signaling pathway in the cortex and hippocampus of rats during aging. Experimental animals (male Wistar rats, 6 months old) were divided into two groups. The AL group was fed ad libitum, whereas the food restricted group (DR) received 100% of the mean daily intake of the AL animals every other day. The animals were examined at the age of 18 and 24 months. Six-month-old animals were used as a control. Glucocorticoid signaling in specific brain regions was examined at the pre-receptor level, as well as regarding the level of expression and glucocorticoid receptor activity by using immunoassays, Western blot, PCR and immunohistochemistry. The results of this study demonstrate an age-related increase in cortical corticosterone concentration. The increase in the hormone level was further detected in DR animals, in both brain regions examined. However, 11β-HSD1, a key enzyme in brain tissue that regulates the availability of corticosterone to its receptors, was increased only in the hippocampi of AL rats and in the cortex of rats subjected to the long-term food restriction. The most pronounced changes in the level of glucocorticoid receptor during aging were observed in the hippocampi of AL animals..

Biomedical application of electroporation: electrochemotherapy and electrogene therapy

Electroporation refers to exposure of cells to external electric field thatresults in transiently or permanently increased permeability of cell membranes. Cancer treatment, where local application of electroporation to tumor nodules is combined with chemotherapeutic drugs bleomycin or cisplatin is called electrochemotherapy. The antitumor effectiveness of electrochemotherapy is primarily based on direct killing of tumor cells due to the increased chemotherapeutic drug uptake, but other mechanisms, such as vascular disrupting action was also demonstrated. Our group is involved in elucidating the underlying mechanism of vascular disrupting action by studying the changes in cytoskeletal proteins after electrochemotherapy in endothelial cells by immunocytochemistry. In addition, metastatic potential and global changes in gene expression of melanoma cells that survived electrochemotherapy were also studied, demonstrating that metastatic potential of cells is not changed and that a very low percentage of genes are down or up regulated after electrochemotherapy, which further supports its safe use in the clinical setting. Another application of electroporation is delivery of plasmid DNA into the cells for gene therapy. Our group is involved in preparation of plasmid DNA with tissue specific promoters and without genes for antibiotic resistance, thus enabling safe use of gene therapy in line with USA Food and Drug Administration (FDA) and European medicines Agency (EMA) recommendations

Supplementary material for the article: Stefanović, V.; Trifković, J.; Djurdjić, S.; Vukojević, V.; Tešić, Ž.; Mutić, J. Study of Silver, Selenium and Arsenic Concentration in Wild Edible Mushroom Macrolepiota Procera, Health Benefit and Risk. Environmental Science and Pollution Research 2016, 23 (21), 22084–22098. https://doi.org/10.1007/s11356-016-7450-2

Supplementary material for: [https://doi.org/10.1007/s11356-016-7450-2]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2348

Supplementary data for article: Đurđić, S. Z.; Sredojević, M.; Trifković, J.; Vukojević, V.; Natić, M.; Tešić, Ž. L.; Mutić, J. Elemental Composition as a Tool for the Assessment of Type, Seasonal Variability, and Geographical Origin of Wine and Its Contribution to Daily Elemental Intake. RSC Advances 2017, 7 (4), 2151–2162. https://doi.org/10.1039/c6ra25105f

Supplementary material for: [https://doi.org/10.1039/c6ra25105f]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2397

Elemental composition as a tool for the assessment of type, seasonal variability, and geographical origin of wine and its contribution to daily elemental intake

The elemental profiles of 63 red and white wine samples from four different regions in Serbia were investigated. Twenty-one elements were analysed (Ca, Mg, Na, K, Fe, Mn, Cu, Zn, Co, Se, Cr, V, Ni, Cd, As, Al, Sb, Pb, Ba, Rb, and Be) by inductively coupled plasma quadrupole mass spectrometry (ICP-Q-MS) and inductively coupled plasma with optical emission spectrometry (ICP-OES). A pattern recognition method was applied in order to classify and differentiate type, seasonal variability, and geographical origin of the wine. Dietary mineral intake for elements was calculated in order to assess their contribution to daily intake. The most important descriptors for discrimination among red and white wine samples were Be, Al, Rb, Mg, K, Cu, Mn, and Na, in descending order. The variables Cd, Pb, As, Sb, V, Na, K, and Zn have the highest influence on vintage-to-vintage classification of red wines. Furthermore, the model revealed the existence of three groups of descriptors for different regions of production. All obtained statistical models confirmed that data from the elemental content of wine samples could be used for accurate prediction of wine type, seasonal variability, and regional origin.Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/2979

Mycotoxins and Mycotoxin Producing Fungi in Pollen: Review

Due to its divergent chemical composition and good nutritional properties, pollen is not only important as a potential food supplement but also as a good substrate for the development of different microorganisms. Among such microorganisms, toxigenic fungi are extremely dangerous as they can synthesize mycotoxins as a part of their metabolic pathways. Furthermore, favorable conditions that enable the synthesis of mycotoxins (adequate temperature, relative humidity, pH, and a(w) values) are found frequently during pollen collection and/or production process. Internationally, several different mycotoxins have been identified in pollen samples, with a noted predominance of aflatoxins, ochratoxins, fumonisins, zearalenone, deoxynivalenol, and T-2 toxin. Mycotoxins are, generally speaking, extremely harmful for humans and other mammals. Current EU legislation contains guidelines on the permissible content of this group of compounds, but without information pertaining to the content of mycotoxins in pollen. Currently only aflatoxins have been researched and discussed in the literature in regard to proposed limits. Therefore, the aim of this review is to give information about the presence of different mycotoxins in pollen samples collected all around the world, to propose possible aflatoxin contamination pathways, and to emphasize the importance of a regular mycotoxicological analysis of pollen. Furthermore, a suggestion is made regarding the legal regulation of pollen as a food supplement and the proposed tolerable limits for other mycotoxins

Neonatal Propofol Anesthesia Changes Expression of Synaptic Plasticity Proteins and Increases Stereotypic and Anxyolitic Behavior in Adult Rats

Propofol is a general anesthetic commonly used in pediatric clinical practices. Experimental findings demonstrate that anesthetics induce widespread apoptosis and cognitive decline in a developing brain. Although anesthesia-mediated neurotoxicity is the most prominent during intense period of synaptogenesis, the effects of an early anesthesia exposure on the synapses are not well understood. The aim of this study was to examine the effects of neonatal propofol anesthesia on the expression of key proteins that participate in synaptogenesis and synaptic plasticity and to evaluate long-term neurobehavioral abnormalities in the mature adult brain. Propofol-injected 7-day-old rats were maintained under 2-, 4-, and 6-h-long anesthesia and sacrificed 0, 4, 16, and 24 h after the termination of each exposure. We showed that propofol anesthesia strongly influenced spatiotemporal expression and/or proteolytic processing of crucial presynaptic (GAP-43, synaptophysin, α-synuclein), trans-synaptic (N-cadherin), and postsynaptic (drebrin, MAP-2) proteins in the cortex and thalamus. An overall decrease of synaptophysin, α-synuclein, N-cadherin, and drebrin indicated impaired function and structure of the synaptic contacts immediately after anesthesia cessation. GAP-43 and MAP-2 adult and juvenile isoforms are upregulated following anesthesia, suggesting compensatory mechanism in the maintaining of the structural integrity and stabilization of developing axons and dendritic arbors. Neonatal propofol exposure significantly altered spontaneous motor activity (increased stereotypic/repetitive movements) and changed emotional behavior (reduced anxiety-like response) in the adulthood, 6 months later. These findings suggest that propofol anesthesia is synaptotoxic in the developing brain, disturbing synaptic dynamics and producing neuroplastic changes permanently incorporated into existing networks with long-lasting functional consequences

Supplementary data for article: Vasić, V.; Đurđić, S.; Tosti, T.; Radoičić, A.; Lušić, D.; Milojković-Opsenica, D.; Tešić, Ž.; Trifković, J. Two Aspects of Honeydew Honey Authenticity: Application of Advance Analytical Methods and Chemometrics. Food Chem. 2020, 305. https://doi.org/10.1016/j.foodchem.2019.125457

Supplementary material for: [https://doi.org/10.1016/j.foodchem.2019.125457]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/3462

Supplementary data for article: Vasić, V.; Gašić, U.; Stanković, D.; Lušić, D.; Vukić-Lušić, D.; Milojković-Opsenica, D.; Tešić, Ž.; Trifković, J. Towards Better Quality Criteria of European Honeydew Honey: Phenolic Profile and Antioxidant Capacity. Food Chemistry 2019, 274, 629–641. https://doi.org/10.1016/j.foodchem.2018.09.045

Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/2917]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2235]Supplementary material for: [https://www.sciencedirect.com/science/article/pii/S0308814618316169?via%3Dihub

Supplementary material for the article: Stefanović, V.; Trifković, J.; Djurdjić, S.; Vukojević, V.; Tešić, Ž.; Mutić, J. Study of Silver, Selenium and Arsenic Concentration in Wild Edible Mushroom Macrolepiota Procera, Health Benefit and Risk. Environmental Science and Pollution Research 2016, 23 (21), 22084–22098. https://doi.org/10.1007/s11356-016-7450-2

Supplementary material for: [https://doi.org/10.1007/s11356-016-7450-2]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2348