Tanja Grahovac

Ms. Tanja Grahovac

orcid

Research Focus & Metrics

Academic Career Length

3Years (2024-Present)

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

Representative Publications

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TUTeodora Vidonja Uzelac
Teodora Vidonja Uzelac
NTNikola Tatalović
Nikola Tatalović
MMMilica Mijović
Milica Mijović
MMMarko Miler
Marko Miler
TGTanja Grahovac
Tanja Grahovac
DBDuško Blagojević
Duško Blagojević
Ibogaine is an organic indole alkaloid that is used in alternative medicine to combat addiction. Numerous cases of life-threatening complications and sudden deaths associated with ibogaine use have been reported, and it has been hypothesized that the adverse effects are related to ibogaine’s tendency to induce cardiac arrhythmias. Considering that the bioavailability of ibogaine and its primary metabolite noribogaine is two to three times higher in female rats than in male rats, we here investigated the effect of a single oral dose (1 or 20 mg/kg) of ibogaine on cardiac histopathology and oxidative/antioxidant balance. Our results show that ibogaine induced dose-dependent cardiotoxic necrosis 6 and 24 h after treatment and that this necrosis was not a consequence of inflammation. In addition, no consistent dose- and time-dependent changes in antioxidant defense or indicators of oxidative damage were observed. The results of this study may contribute to a better understanding of ibogaine-induced cardiotoxicity, which is one of the main side effects of ibogaine use in humans and is often fatal. Nevertheless, based on this experiment, it is not possible to draw a definitive conclusion regarding the role of redox processes or oxidative stress in the occurrence of cardiotoxic necrosis after ibogaine administration.

22 July 2025 in Life
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NDNemanja Dimic
Nemanja Dimic
GMGorica Maric
Gorica Maric
ZDZorana Slobodan Orescanin Dusic
Zorana Slobodan Orescanin Dusic
TGTanja Grahovac
Tanja Grahovac
TUTeodora Vidonja Uzelac
Teodora Vidonja Uzelac
MSMarina Stojanovic
Marina Stojanovic
This study evaluates the influence of general anesthesia (GA) and spinal anesthesia (SA) on physiological and oxidative stress in parturients undergoing elective cesarean section, one of the most frequently performed surgical procedures worldwide. A total of 101 pregnant women were included, categorized into GA (n = 51) and SA (n = 50) groups. Blood samples were collected at three time points: one hour before surgery (Measurement 1), at umbilical cord clamping (Measurement 2), and two hours post-surgery (Measurement 3). Biomarkers of oxidative stress, complete blood count, and levels of biochemical parameters were measured. In second and/or third measurement, biochemical blood analysis showed increased prolactin and cortisol levels, followed by spike of glucose and insulin in the GA group. However, levels of tri-iodothyronine were reduced in both groups in the third measurement. Glutathione S-transferase (GST) activity was increased in both groups in third measurement. The results showed increased concentrations of total SH groups and decreased concentrations of non-protein SH groups in the GA group during Measurement 2. Lymphocyte count was found to be predictor of GST levels. The results indicate more a pronounced endocrine response in GA group and speak in favor of spinal anesthesia. Both kinds of anesthesia are equally safe in terms of the oxidative status of the tissue.

28 October 2025 in Life
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TGTanja Grahovac
Tanja Grahovac
TUTeodora Vidonja Uzelac
Teodora Vidonja Uzelac
ZDZorana Slobodan Orescanin Dusic
Zorana Slobodan Orescanin Dusic
Dusan M. SpasicDusan M. Spasic
Dusan M. Spasic
MMMilica Mijović
Milica Mijović
DBDuško Blagojević
Duško Blagojević
Atypical antipsychotics (AAP), including clozapine (Clo), aripiprazole (Ari), and risperidone (Ris), are widely used in psychiatry but can lead to kidney damage due to oxidative stress. This study investigated whether dietary supplementation with selected antioxidants—ellagic acid, vitamin C, zinc, and seleno-methionine (SeMet) in fish oil, formulated as the composite product “ProCloSupp” (PCS)—can mitigate the oxidative damage induced by subchronic administration of AAP. Rats were treated with each antipsychotic for 28 days, with PCS added in the last 14 days. The kidney tissue was examined histologically and by determining the activities of antioxidant enzymes (copper, zinc and manganese superoxide dismutase—CuZn SOD and Mn SOD, catalase—CAT, glutathione peroxidase—GPx, glutathione reductase—GR, glutathione S-transferase—GST). All AAPs caused discrete to moderate renal damage and significant changes in enzyme profiles, which were most pronounced with Ari. Clo and Ari significantly decreased CuZn SOD and Mn SOD activity, while Ris only affected Mn SOD. Clo additionally increased CAT activity, while Ari increased GPx activity. Antioxidant-related protein levels increased only in the Ris group. PCS supplementation increased CuZn SOD and GPx activities and was associated with less pronounced histopathological changes than antipsychotic treatment alone. In conclusion, subchronic Clo, Ari, and Ris exposure induces oxidative renal damage in rats, while PCS supplementation enhances antioxidant defences and attenuates tissue damage. These results support PCS as a potential nephroprotective strategy in antipsychotic therapy.

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RMRadmil Marić
Radmil Marić
BĆBranislava Ćurčić
Branislava Ćurčić
TUTeodora Vidonja Uzelac
Teodora Vidonja Uzelac
TGTanja Grahovac
Tanja Grahovac
ZDZorana Slobodan Orescanin Dusic
Zorana Slobodan Orescanin Dusic
Dragana DrakulDragana Drakul
Dragana Drakul
Atherosclerosis is a progressive vascular disease characterized by lipid-rich plaque accumulation, oxidative stress, and chronic inflammation, contributing to coronary heart disease, stroke, and peripheral arterial disease. This study investigated the impact of inflammation, vascular calcification, and statin therapy on redox balance in blood and carotid artery plaques, aiming to identify potential biomarkers for disease assessment. Thirty-two patients undergoing carotid endarterectomy provided 34 plaque samples. Enzyme activities in plaque/erythrocytes and –SH group concentration in plasma/plaque were measured. Pathological analysis was performed to determine inflammation/calcification grade, the presence of mast cells and plaque composition. The results showed that mast cells were associated with reduced non-protein –SH groups, indicating selective thiol consumption and serving as a qualitative marker of oxidative burden. Reduced catalase activity in erythrocytes was associated with advanced calcification, pointing to long-standing systemic oxidative stress. Statin therapy enhanced systemic superoxide-dismutase 1 activity, increased –SH groups, and modulated plaque-specific glutathione reductase activity, attenuating sex-related differences in redox regulation. These findings highlight the complex interplay between systemic and local oxidative processes in atherosclerosis through alterations in redox-related biomarkers such as plasma –SH group concentrations and catalase activity.

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Marija VukcevicMarija Vukcevic
Marija Vukcevic
Dusan M. SpasicDusan M. Spasic
Dusan M. Spasic
VKVladimir Kešelj
Vladimir Kešelj
LALena Platanić Arizanović
Lena Platanić Arizanović
TGTanja Grahovac
Tanja Grahovac
MNMilan R. Nikolić
Milan R. Nikolić
This study examined alterations in serum redox biomarkers before and one month after administration of the coronavirus disease 2019 (COVID-19) booster (third) doses across four vaccine regimens. A longitudinal cohort of 410 adults was analyzed following homologous Pfizer-BioNTech, Sinopharm [Vero Cell]-Inactivated, Sputnik V, or heterologous Sinopharm/Pfizer vaccination. Serum total proteins, albumin, total thiols, nitrites, ferric-reducing antioxidant power (FRAP), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity were measured, with DPPH interpreted as an ex vivo surrogate of serum radical-scavenging capacity. Additional analyses included stratification by prior severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, multivariable regression, correlation analysis, effect-size estimation, and sensitivity testing. Booster vaccination was associated with modest but consistent decreases in DPPH activity, albumin, and total proteins, whereas FRAP, nitrite, and total thiol levels remained stable. This pattern supports a transient shift in antioxidant buffering capacity but, by itself, does not exclude oxidative stress, as direct oxidative damage markers were not assessed. The most pronounced changes were observed in Sinopharm-based regimens, particularly in the heterologous Sinopharm/Pfizer group. Prior SARS-CoV-2 infection did not materially alter the qualitative response pattern, whereas older age and comorbidities were associated with greater declines in DPPH activity and albumin. Overall, the findings indicate a modest, transient redox-associated response following booster-induced immune activation and suggest that host-related factors, such as age and comorbidity burden, may accentuate short-term changes in antioxidant buffering capacity.

Verified
Journal Article
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TGTanja Grahovac
Tanja Grahovac
ZDZorana Slobodan Orescanin Dusic
Zorana Slobodan Orescanin Dusic
Aleksandra Nikolić-KokićAleksandra Nikolić-Kokić
Aleksandra Nikolić-Kokić
DBDuško Blagojević
Duško Blagojević
TUTeodora Vidonja Uzelac
Teodora Vidonja Uzelac
Redox homeostasis is driven by the ratio of the concentrations of cellular redox couples. The aim of this study was to reduce 2GSH/GSSG turnover in an ex vivo ileum by the irreversible inhibition of glutathione reductase (GR) activity (by BCNU) and evaluate its effects on contractility, antioxidant enzyme activity, and thiol levels. Increasing concentrations of BCNU as well as a single EC50 BCNU dose significantly reduced both contraction amplitude and GR activity. The addition of cumulative doses of both GSH and GSSG after EC50 BCNU caused further dose-dependent amplitude reduction, but turned GR activity to control levels and reduced CuZn-superoxide dismutase activity; cumulative doses of GSH also decreased catalase activity. Both GSH and GSSG cumulative doses decreased the contractility of non-treated control ileum in a dose-dependent manner, while GSH also increased glutathione peroxidase (GPx) activity. The correlation analysis showed a negative relationship between contractility and non-protein thiols, and positive correlations between catalase and GPx activities in BCNU treated ileum, as well as between GPx and non-protein thiols in solvent controls. The results present a framework for how glutathione turnover and ileum contractility are linked.