Iustina-Mirabela Cristea

Dr. Iustina-Mirabela Cristea


Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

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

Representative Publications

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Journal Article
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Pricop Maria AlexandraPricop Maria Alexandra
Pricop Maria Alexandra
ANAdina Negrea
Adina Negrea
PBPascu Bogdan
Pascu Bogdan
NNNicoleta Sorina Nemeş
Nicoleta Sorina Nemeş
Mihaela CiopecMihaela Ciopec
Mihaela Ciopec
ICIustina-Mirabela Cristea
Iustina-Mirabela Cristea
Copper nanoparticles (CuNPs) have attracted attention due to their low cost and high specific surface area. In this work, a simple and inexpensive two-step synthesis method was proposed to prepare highly stable and well-dispersed spherical CuNPs in solution with a particle size of approximately 37 nm. Synthesis of CuNPs was carried on in the presence of complexing agent trisodium citrate (TSC), while for the chemical reduction step, sodium borohydride (NaBH4) was used. Taking into account the potential of this type of nanoparticles, their synthesis and characterization represent a current and relevant topic in the field. The ability to control the size, shape and properties of CuNPs by adjusting the synthesis parameters (pH, precursor:stabilizer:reductant ratio, homogenization time, temperature) offers extraordinary flexibility in the development of these materials. The combination of characterization techniques such as SEM, EDX, UV–Vis, Raman, FT-IR and AFM provides a thorough understanding of the structure and properties of CuNPs, allowing the modulation of the properties of the obtained nanoparticles in the desired direction. Based on the studies, the copper reduction mechanism was proposed. For the theoretical verification of the size of the experimentally obtained spherical CuNPs, Mie theory was applied. A stability study of the synthesized CuNPs in optimal conditions was performed using UV–Vis analysis at specific time intervals (1, 3, 30 and 60 days), the sample being kept in the dark, inside a drawer at 25 °C. The CuNPs obtained after setting the optimal synthesis parameters (Cu(II):TSC:BH4+ = 1:1:0.2, pH = 5, homogenization time 60 min and temperature 25 °C) were then tested to highlight their antibacterial effect on some reference bacterial strains. The obtained CuNPs demonstrated very good antimicrobial efficacy compared to traditional antimicrobials, for both Gram-negative and Gram-positive bacteria. This may reduce the development of antimicrobial resistance, an urgent medical issue. After evaluating the cytotoxic effects of CuNPs on the SKBR3 cancer cell line, a significant decrease in cell proliferation was observed at the 0.5 mg/mL concentration, with a reduction of 89% after 60 h of cultivation. Higher concentrations of CuNPs induced a more rapid cytotoxic effect, leading to an accelerated decline in cell viability.

5 December 2024 in Molecules
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IAIvan Alexandra
Ivan Alexandra
ALAlexandra T Lukinich-Gruia
Alexandra T Lukinich-Gruia
ICIustina-Mirabela Cristea
Iustina-Mirabela Cristea
MPMaria-Alexandra Pricop
Maria-Alexandra Pricop
CCCRENGUTA LIVIA CALMA
CRENGUTA LIVIA CALMA
VPVirgil Păunescu
Virgil Păunescu
Quercetin is a natural flavonoid renowned for its potent antioxidant, anti-inflammatory, anti-diabetic, and antibacterial properties, making it a highly promising candidate for the treatment of various medical conditions. Our current study investigates the influence of quercetin on energy metabolism, fatty acid composition, oxidative stress gene expression, and sirtuin expression in early- and late-stage passages of stem cells derived from human exfoliated deciduous teeth (SHEDs). Mitochondrial respiration was analyzed by measuring oxygen consumption following a 24 h quercetin treatment, while fatty acid profiles were examined using gas chromatography–mass spectrometry (GC-MS). Additionally, quantitative PCR (qPCR) was used to assess the expression of oxidative stress genes and sirtuins. In younger SHEDs, quercetin enhances metabolic activity and mitochondrial respiration, although higher doses may decrease mitochondrial activity. Conversely, in older, senescent SHEDs, quercetin supports mitochondrial function at lower concentrations but appears to inhibit respiration at higher doses. These results suggest that quercetin may hold therapeutic potential for maintaining SHED viability and function, especially at lower doses in older cells. Further research is essential to fully elucidate a dose-dependent effect of quercetin and optimize its applications in regenerative medicine.

25 October 2024 in Plants
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MPMaria-Alexandra Pricop
Maria-Alexandra Pricop
ALAlexandra T Lukinich-Gruia
Alexandra T Lukinich-Gruia
ICIustina-Mirabela Cristea
Iustina-Mirabela Cristea
VPVirgil Păunescu
Virgil Păunescu
CTCalin Adrian Tatu
Calin Adrian Tatu
Aristolochia sp. plants are used in traditional medicine because of their immunostimulatory and anticarcinogenic properties, despite their content of aristolochic acids (AAs), carcinogenic and nephrotoxic agents. Therefore, ethanolic extracts of Aristolochia clematitis leaves, a specie growing in Western Romania, were obtained to study antioxidant and cytotoxic effects. The antioxidant capacity of the extract was evaluated by five in vitro chemical-based assays, proving that ABTS assay was a better method for this type of evaluation showing an IC50 of 160.89 ± 0.21 µg/mL. Furthermore, the cytotoxic effects of the extract were established by an IC50 of 216 µg/mL for 24 h by MTT assay, followed by a cell-based assay on Caco-2 cells by the ABTS method. The antioxidant effects of the A. clematitis extract demonstrate potential therapeutic applications in complementary medicine.

Verified
Journal Article
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IAIvan Alexandra
Ivan Alexandra
ICIustina-Mirabela Cristea
Iustina-Mirabela Cristea
ATAda Telea
Ada Telea
COCamelia Oprean
Camelia Oprean
Atena GaluscanAtena Galuscan
Atena Galuscan
VPVirgil Păunescu
Virgil Păunescu
The metabolic regulation of stemness is widely recognized as a crucial factor in determining the fate of stem cells. When transferred to a stimulating and nutrient-rich environment, mesenchymal stem cells (MSCs) undergo rapid proliferation, accompanied by a change in protein expression and a significant reconfiguration of central energy metabolism. This metabolic shift, from quiescence to metabolically active cells, can lead to an increase in the proportion of senescent cells and limit their regenerative potential. In this study, MSCs from human exfoliated deciduous teeth (SHEDs) were isolated and expanded in vitro for up to 10 passages. Immunophenotypic analysis, growth kinetics, in vitro plasticity, fatty acid content, and autophagic capacity were assessed throughout cultivation to evaluate the functional characteristics of SHEDs. Our findings revealed that SHEDs exhibit distinctive patterns of cell surface marker expression, possess high self-renewal capacity, and have a unique potential for neurogenic differentiation. Aged SHEDs exhibited lower proliferation rates, reduced potential for chondrogenic and osteogenic differentiation, an increasing capacity for adipogenic differentiation, and decreased autophagic potential. Prolonged cultivation of SHEDs resulted in changes in fatty acid composition, signaling a transition from anti-inflammatory to proinflammatory pathways. This underscores the intricate connection between metabolic regulation, stemness, and aging, crucial for optimizing therapeutic applications.

6 September 2024 in Applied Sciences
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ALAlexandra T Lukinich-Gruia
Alexandra T Lukinich-Gruia
CCCRENGUTA LIVIA CALMA
CRENGUTA LIVIA CALMA
FSFlavia Anne-Elise Szekely
Flavia Anne-Elise Szekely
ICIustina-Mirabela Cristea
Iustina-Mirabela Cristea
MPMaria-Alexandra Pricop
Maria-Alexandra Pricop
VPVirgil Păunescu
Virgil Păunescu
Aristolochic acids, compounds derived from Aristolochiaceae plant species, are associated with significant renal nephrotoxicity and carcinogenicity. Aristolochic acid I (AAI), the most predominant and potent of these compounds, is a primary etiological agent in acute and chronic kidney diseases such as Aristolochic Acid Nephropathy (AAN) and Balkan Endemic Nephropathy (BEN). Due to the kidneys’ critical role in xenobiotic excretion, they are the primary organs affected by AAI toxicity. Recent in vitro and in vivo studies have highlighted mitochondrial dysfunction as a crucial factor in the pathogenesis of these kidney diseases. This review provides an update on the recent advances in understanding the causes of acquired mitochondrial dysfunction within the context of AAN and BEN. Key findings include the identification of mitochondrial DNA depletion, loss of mitochondrial membrane potential, and decreased ATP production as significant contributors to kidney damage. Additionally, oxidative stress markers and inflammatory mediators have been implicated in disease progression. Potential therapeutic approaches, such as the use of antioxidants like vitamin C and catalpol, have shown promise in mitigating AAI-induced cytotoxicity. Furthermore, future predictive approaches like pharmacogenomics could pave the way for novel mitochondria-targeted treatments. A comprehensive characterization of mitochondrial function, its underlying molecular mechanisms, and specific biomarkers could offer valuable insights and potential therapeutic options, significantly impacting the current management of AAN and BEN.

Verified
Journal Article
Open access
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IAIvan Alexandra
Ivan Alexandra
Pricop Maria AlexandraPricop Maria Alexandra
Pricop Maria Alexandra
ALAlexandra T Lukinich-Gruia
Alexandra T Lukinich-Gruia
ICIustina-Mirabela Cristea
Iustina-Mirabela Cristea
ANAdina Negrea
Adina Negrea
CTCalin Adrian Tatu
Calin Adrian Tatu
The use of copper nanoparticles (CuNPs) seems to be an alternative therapeutic strategy for cancer therapy due to low-cost synthesis and anticancer activity. In this work, CuNPs’ effects were tested in various concentrations on two types of cells: mesenchymal stem cells (MSCs) and a breast cancer cell line, SKBR3. The concentrations (0.25 mM, 0.5 mM, 1 mM and 2 mM) were first tested on an impedance-based cytotoxicity assay and then used in further cellular metabolic assays. Next, several techniques were applied to test the chosen concentrations: assessment of apoptosis, intracellular reactive oxygen species (ROS) levels, oxidative stress-related gene expression, assessment of mitochondrial respiration and fatty acid methyl ester (FAME) profile evaluation. The higher CuNP concentrations tested on the SKBR3 cell line showed a dose-dependent decrease in the cell index. SKBR3 cells displayed increased CAT and SOD expression, revealed by strong dose-dependent fluorescence. Annexin/PI staining confirmed increased SKBR3 cell death induced by the higher doses of CuNPs. SKBR3 revealed higher baseline respiratory capacity compared to MSCs. Fatty acid methyl esters (FAMEs) are in higher abundance in MSCs compared to the SKBR3 cell line. The different metabolic response in the tested cells to the CuNPs’ presence could help establish a future personalized treatment for breast cancer patients.