Leon Zagrean

Prof. Dr. Leon Zagrean

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Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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20 August 2020 in Biomolecules
Verified
Journal Article
Open access
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DCDiana Maria Chitimus
Diana Maria Chitimus
Mihaela PopescuMihaela Popescu
Mihaela Popescu
SVSuzana Elena Voiculescu
Suzana Elena Voiculescu
Ana-Maria ZagreanAna-Maria Zagrean
Ana-Maria Zagrean
BPBogdan Pavel
Bogdan Pavel
Ana-Maria ZagreanAna-Maria Zagrean
Ana-Maria Zagrean
There is a growing consensus that the antioxidant and anti-inflammatory properties of melatonin are of great importance in preserving the body functions and homeostasis, with great impact in the peripartum period and adult life. Melatonin promotes adaptation through allostasis and stands out as an endogenous, dietary, and therapeutic molecule with important health benefits. The anti-inflammatory and antioxidant effects of melatonin are intertwined and are exerted throughout pregnancy and later during development and aging. Melatonin supplementation during pregnancy can reduce ischemia-induced oxidative damage in the fetal brain, increase offspring survival in inflammatory states, and reduce blood pressure in the adult offspring. In adulthood, disturbances in melatonin production negatively impact the progression of cardiovascular risk factors and promote cardiovascular and neurodegenerative diseases. The most studied cardiovascular effects of melatonin are linked to hypertension and myocardial ischemia/reperfusion injury, while the most promising ones are linked to regaining control of metabolic syndrome components. In addition, there might be an emerging role for melatonin as an adjuvant in treating coronavirus disease 2019 (COVID 19). The present review summarizes and comments on important data regarding the roles exerted by melatonin in homeostasis and oxidative stress and inflammation related pathologies.

9 September 2020 in Brain Sciences
Verified
Journal Article
Open access
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Ioana GeorgescuIoana Georgescu
Ioana Georgescu
DPDaniela Popa
Daniela Popa
LZLeon Zagrean
Leon Zagrean
The mediodorsal nucleus (MD) represents just one piece of a complex relay structure situated within the brain, called the thalamus. MD is characterized by its robust interconnections with other brain areas, especially with limbic-related structures. Given the close anatomo-functional relationship between the MD and the limbic system, this particular thalamic nucleus can directly influence various affective behaviors and participate in cognition. In this work, we review data collected from multiple anatomical studies conducted in rodent, human, and non-human primates, highlighting the complexity of this structure and of the neural networks in which it takes part. We provide proof that the MD is involved in the unification of several anatomical structures, being able to process the information and influence the activity in numerous cortical and subcortical neural circuits. Moreover, we uncover intrinsic and extrinsic mechanisms that offer MD the possibility to execute and control specific high functions of the nervous system. The collected data indicate the great importance of the MD in the limbic system and offer relevant insight into the organization of thalamic circuits that support MD functions.

4 January 2021 in Journal of Clinical Medicine
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Journal Article
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ARAdrian Eugen Rosca
Adrian Eugen Rosca
Ana-Maria VlădăreanuAna-Maria Vlădăreanu
Ana-Maria Vlădăreanu
AMAlina Mititelu
Alina Mititelu
BPBogdan Ovidiu Popescu
Bogdan Ovidiu Popescu
CBCorin Badiu
Corin Badiu
LZLeon Zagrean
Leon Zagrean
Anabolic androgenic steroids (AAS), simply called “androgens”, represent the most widespread drugs used to enhance performance and appearance in a sporting environment. High-dosage and/or long-term AAS administration has been associated frequently with significant alterations in the cardiovascular system, some of these with severe endpoints. The induction of a prothrombotic state is probably the most life-threatening consequence, suggested by numerous case reports in AAS-abusing athletes, and by a considerable number of human and animal studies assessing the influence of exogenous androgens on hemostasis. Despite over fifty years of research, data regarding the thrombogenic potential of exogenous androgens are still scarce. The main reason is the limited possibility of conducting human prospective studies. However, human observational studies conducted in athletes or patients, in vitro human studies, and animal experiments have pointed out that androgens in supraphysiological doses induce enhanced platelet activity and thrombopoiesis, leading to increased platelet aggregation. If this tendency overlaps previously existing coagulation and/or fibrinolysis dysfunctions, it may lead to a thrombotic diathesis, which could explain the multitude of thromboembolic events reported in the AAS-abusing population. The influence of androgen excess on the platelet activity and fluid–coagulant balance remains a subject of debate, urging for supplementary studies in order to clarify the effects on hemostasis, and to provide new compelling evidence for their claimed thrombogenic potential.

27 January 2022 in Journal of Clinical Medicine
Verified
Journal Article
Open access
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ARAdrian Eugen Rosca
Adrian Eugen Rosca
Ana-Maria VlădăreanuAna-Maria Vlădăreanu
Ana-Maria Vlădăreanu
RMRadu Mirica
Radu Mirica
CACristina-Mihaela Anghel-Timaru
Cristina-Mihaela Anghel-Timaru
AMAlina Mititelu
Alina Mititelu
LZLeon Zagrean
Leon Zagrean
Taurine is a semi-essential, the most abundant free amino acid in the human body, with a six times higher concentration in platelets than any other amino acid. It is highly beneficial for the organism, has many therapeutic actions, and is currently approved for heart failure treatment in Japan. Taurine has been repeatedly reported to elicit an inhibitory action on platelet activation and aggregation, sustained by in vivo, ex vivo, and in vitro animal and human studies. Taurine showed effectiveness in several pathologies involving thrombotic diathesis, such as diabetes, traumatic brain injury, acute ischemic stroke, and others. As human prospective studies on thrombosis outcome are very difficult to carry out, there is an obvious need to validate existing findings, and bring new compelling data about the mechanisms underlying taurine and derivatives antiplatelet action and their antithrombotic potential. Chloramine derivatives of taurine proved a higher stability and pronounced selectivity for platelet receptors, raising the assumption that they could represent future potential antithrombotic agents. Considering that taurine and its analogues display permissible side effects, along with the need of finding new, alternative antithrombotic drugs with minimal side effects and long-term action, the potential clinical relevance of this fascinating nutrient and its derivatives requires further consideration.

16 December 2020 in Neonatology
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Journal Article
Closed access
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Isac SebastianIsac Sebastian
Isac Sebastian
APAnca Maria Panaitescu
Anca Maria Panaitescu
MIMara-Ioana Ionescu
Mara-Ioana Ionescu
VZVlad Zeca
Vlad Zeca
NCNatalia Cucu
Natalia Cucu
Ana-Maria ZagreanAna-Maria Zagrean
Ana-Maria Zagrean
Background: Citicoline represents a dietary source of choline, an essential nutrient, and precursor of cell membrane components, highly required during development and post-injury recovery. Objectives: We previously showed that perinatal asphyxia (PA) induces hippocampal neuroinflammation and injury that are subject to epigenetic change by maternal diet. The present study investigates maternal citicoline-supplemented diet (CSD) impact on offspring hippocampal response to PA. Methods: Six-day-old Wistar rats from mothers with standard-diet or CSD were exposed to PA. The hippocampal inflammation and injury were assessed by interleukin-1 beta (IL-1b), tumor necrosis factor-alpha (TNFα), and S-100B protein (S-100B), 24–48 h post-asphyxia. The microRNAs species miR124, miR132, miR134, miR146, and miR15a were measured from the hippocampus 24 h post-asphyxia, to investigate its epigenetic response to PA and maternal diet. At maturity, the offspring’s behavior was analyzed using open field (OFT), T-maze (TMT), and forced swimming (FST) tests. Results: Our data show that the maternal CSD decreased IL-1b (p = 0.02), TNFα (p = 0.007), and S100B (p = 0.01) at 24 h postexposure, upregulated miR124 (p = 0.03), downregulated miR132 (p = 0.002) and miR134 (p = 0.001), shortened the immobility period in FST (p = 0.01), and increased the percentage of passed trials in TMT (p = 0.01) compared to standard-diet. Conclusions: Maternal CSD reduces hippocampal inflammation and S100B level, triggers epigenetic changes related to homeostatic synaptic plasticity, memory formation, and neuronal tolerance to asphyxia, decreases the depressive-like behavior, and improves the lucrative memory in offspring subjected to PA. Thus, citicoline could be valuable as a maternal dietary strategy in improving the brain response to PA.

1 November 2019 in Brain Sciences
Verified
Journal Article
Open access
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BPBogdan Pavel
Bogdan Pavel
FMFabien Menardy
Fabien Menardy
DRDiana Rotaru
Diana Rotaru
APAlexandru Cătălin Pâslaru
Alexandru Cătălin Pâslaru
CACamelia Acatrinei
Camelia Acatrinei
Ana-Maria ZagreanAna-Maria Zagrean
Ana-Maria Zagrean
The role of the claustrum in consciousness and vigilance states was proposed more than two decades ago; however, its role in anesthesia is not yet understood, and this requires more investigation. The aim of our study was to assess the impact of claustrum electrical stimulation during isoflurane anesthesia in adult rats. The claustrum in the left hemisphere was electrically stimulated using a bipolar tungsten electrode inserted stereotaxically. In order to monitor the anesthetic depth, the electrocorticogram (ECoG) was recorded before, during, and after claustrum stimulation using frontal and parietal epidural electrodes placed over the left hemisphere. After reaching stabilized slow-wave isoflurane anesthesia, twenty stimuli, each of one second duration with ten seconds interstimulus duration, were applied. ECoG analysis has shown that, after a delay from the beginning of stimulation, the slow-wave ECoG signal changed to a transient burst suppression (BS) pattern. Our results show that electrical stimulation of the claustrum area during slow-wave isoflurane anesthesia induces a transitory increase in anesthetic depth, documented by the appearance of a BS ECoG pattern, and suggests a potential role of claustrum in anesthesia.