Nebojša Mandić-Kovačević

Oxidative stress is a critical pathophysiological factor in sepsis. Ursodeoxycholic acid (UDCA), a bile acid with anti-inflammatory, antioxidant, and anti-apoptotic properties, may protect against lipopolysaccharide (LPS)-induced myocardial injury. In an experimental study, 32 male Wistar rats were randomly assigned to four groups: control, LPS, UDCA, and UDCA + LPS. UDCA was administered orally for 10 days prior to LPS-induced endotoxemia. Serum levels of high-sensitive troponin I (hsTnI), homocysteine, and oxidative stress markers were measured, and immunohistochemistry and immunofluorescence were used to assess inflammation (nuclear factor kappa B, NF-κB), apoptosis (caspase 3), and signaling pathways related to protein kinase B (Akt)/NF-κB and silent information regulator 1 (SIRT1)/nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1). UDCA pretreatment significantly reduced myocardial pathological changes, serum hsTnI, homocysteine, and total oxidative stress compared with LPS alone. It enhanced catalase (CAT) activity and glutathione (GSH) levels while lowering thiobarbituric acid reactive substances (TBARS) and nitrite concentrations in cardiac tissue. UDCA modulated cellular signaling by decreasing Akt phosphorylation and activating the SIRT1/Nrf2/HO-1 pathway. These results indicate that UDCA protects the heart from LPS-induced damage by reducing oxidative stress, inflammation, and apoptosis. UDCA modulates cellular signaling by decreasing pro-inflammatory pathways and activating anti-inflammatory pathways associated with SIRT1/Nrf2/HO-1 signaling, emphasizing its key role in myocardial protection during sepsis.

In obstetrics, diazepam is commonly used to treat anxiety, insomnia and as a second‐line treatment for seizures in preeclampsia and eclampsia. However, the effects of diazepam on the oxidative balance and vascular function of the umbilical circulation are still insufficiently studied. In this study, we investigated the effects of suprapharmacological concentrations of diazepam in an in vitro model of human umbilical artery (HUA) injury, induced by incubation with 1 mM homocysteine, representing experimental conditions that mimic hyperhomocysteinemia. HUAs were divided into four groups: control (C), diazepam (D) alone (100 μ mol/L), homocysteine (Hcy) alone (1 mM), and combined treatment (HcyD). For oxidative stress assays, data were obtained from 8–10 individual HUA samples per group, with lipid peroxidation, nitrite (NO ₂ ⁻ ) levels, and SOD, CAT, and GSH activities determined spectrophotometrically. Histological and TUNEL analyses were performed in triplicate ( n = 3 per group), whereas vascular reactivity experiments, using an organ bath system, included six individual vessel samples per group. Statistical analysis was performed using the paired Student′s t ‐test ( p < 0.05). Diazepam alone significantly reduced superoxide dismutase (SOD) activity, indicating an apparent impairment of antioxidant defenses. In contrast, concomitant treatment under hyperhomocysteinemia lowered the levels of thiobarbituric acid reactive substances (TBARSs) and NO ₂ ⁻ , suggesting partial protection against lipid peroxidation and nitrosative stress. Histologically, diazepam preserved arterial structure with minor subendothelial changes, whereas cotreatment reduced homocysteine‐induced endothelial disruption, smooth muscle disarray, and medial connective tissue loss. Apoptotic index was significantly reduced with cotreatment comparing to hyperhomocysteinemia, whereas diazepam alone showed values similar to control. Functionally, diazepam significantly reduced serotonin‐induced contraction of HUAs, but this vascular effect was attenuated under hyperhomocysteinemic conditions. Overall, concomitant treatment with diazepam partially attenuated oxidative and structural changes induced by hyperhomocysteinemia in our experimental setting, in a preclinical model mimicking selected pathophysiological aspects of preeclampsia.

Acetylcholinesterase (AChE) inhibitors constitute a large and chemically diverse group of compounds that inhibit the enzyme AChE. Some of these compounds that are used to treat Alzheimer’s disease have been reported to have favourable cardiovascular effects, i.e., a 35% reduction of the risk for cardiovascular disease. There has been a growing interest in AchE inhibitors as a potential therapeutic approach for cardiovascular diseases, especially heart failure (HF), since they correct the autonomic imbalance, a key component in the development of heart failure. In the present study, HF was induced in male Wistar albino rats using an isoprenaline model (85 mg/kg/day s.c. for 2 days, followed by 3 weeks of HF development) of heart failure with preserved ejection fraction. Afterwards, rats were treated with pyridostigmine (20 mg/kg/day in tap water for 14 days), while the controls received no treatment. Electrocardiographic and echosonographic measurements were obtained, and samples were taken for antioxidative status measurement and histopathological analysis. Administration of pyridostigmine resulted in preservation of cardiac contractile function (↑ EF), coupled with a decrease in chamber wall thinning (↑ PWDd, ↑ PWDs) and dilatation progression (↓ LVIDd, ↓ LVIDs). Additionally, histopathological findings showed significantly reduced tissue damage score and attenuation of cardiac fibrosis development, indicating the cardioprotective potential of pyridostigmine when used as treatment for the early stages of heart failure; however, further investigations are needed to fully investigate the interplay between the several proposed mechanisms through which AChE inhibitors express their protective effects.

Acute mesenteric ischemia (AMI) is a life-threatening condition characterised by oxidative stress, inflammation, apoptosis, and necrosis of intestinal epithelial cells. Different drugs with vasoactive, antioxidant, and anti-inflammatory properties have been used to treat AMI. Levosimendan is a drug with proven anti-ischemic effects used in the management of acute congestive heart failure. This study evaluated the protective effects of levosimendan pretreatment on intestinal, as well as lung, heart, and kidney tissue in a rat model of mesenteric artery ischemia/reperfusion (I/R) injury. Male Wistar rats (N = 24) were divided into four groups: control, I/R, levosimendan (LS) 1 mg/kg i.p, and LS + I/R (1 mg/kg i.p. 30 min before injury). I/R by itself caused elevation of oxidative markers (thyobarbituric acid reactive species (TBARS), hydrogen peroxide (H₂O₂), super oxide anjon radical (O₂⁻), and nitrogen dioxide (NO₂⁻)), induced inflammation (macrophage infiltration and Interleukin-6 (IL-6) production), and apoptosis (nuclear factor kappa light-chain enhancer of activated B cells (NF-κB), cleaved caspase-3 (CC3), and terminal deoxy-nucleotidyl transferase (TdT)-mediated dUTP nick end labelling (TUNEL)). Levosimendan pretreatment significantly reduced oxidative stress markers and enhanced antioxidant defences (catalase (CAT), reduced glutathione (GSH), and superoxide dismutase (SOD)). Histological analysis revealed reduced mucosal damage and preserved goblet cells in intestinal tissue. Similar protective effects of levosimendan were observed in other organs such as lung, heart, and kidney. Immunohistochemistry showed reduced epithelial apoptosis and upregulation of antioxidant and anti-inflammatory proteins. These findings highlight levosimendan’s ability to protect mesenteric I/R tissue injury and multi-organ damage by suppressing oxidative stress, inflammation, and apoptosis, emphasising its therapeutic potential in clinical settings.

Autonomic imbalance is one of the major pathological disturbances in chronic heart failure (CHF). Additionally, enhanced oxidative stress and inflammation are considered to be the main contributors to the disease progression. A growing body of evidence suggests cholinergic stimulation as a potential therapeutic approach in CHF, since it corrects the autonomic imbalance and alters the inflammatory response via the cholinergic anti-inflammatory pathway. Although previous research has provided some insights into the potential mechanisms behind these effects, there is a gap in knowledge regarding different cholinergic stimulation methods and their specific mechanisms of action. In the present study, an isoprenaline model (5 mg/kg/day s.c. for 7 days, followed by 4 weeks of CHF development) was used. Afterwards, rats received pyridostigmine (22 mg/kg/day in tap water for 14 days) or no treatment. Pyridostigmine treatment prevented the progression of CHF, decreasing chamber wall thinning (↑ PWDd, ↑ PWDs) and left ventricle dilatation (↓ LVIDd, ↓ LVIDs), thus improving cardiac contractile function (↑ EF). Additionally, pyridostigmine improved antioxidative status (↓ TBARS, ↓ NO₂⁻; ↑ CAT, ↑ GSH) and significantly reduced cardiac fibrosis development, confirmed by pathohistological findings and biochemical marker reduction (↓ MMP2, ↓ MMP9). However, further investigations are needed to fully understand the exact cellular mechanisms involved in the CHF attenuation via pyridostigmine.

The pharmacological potential of Lamiaceae plants is primarily linked to their high content of phenolic acids and flavonoids, known for strong antioxidant properties. This study investigated the antioxidant activity of ten widely used Lamiaceae herbs—oregano, lavender, basil, savory, garden thyme, wild thyme, sage, rosemary, lemon balm, and mint—prepared as traditional infusions and microwave-assisted extracts. The antioxidant capacity was evaluated using spectrophotometric assays, and total phenolics and flavonoids were quantified via spectrophotometry and HPLC. Chemometric analysis (PCA) was applied to explore correlations among antioxidant parameters. The results demonstrated excellent antioxidant activity across all samples. The IC50 for DPPH radicals was in the range from 3.73(0.13) to 8.03(0.17) μg/mL and that for ABTS radicals was from 2.89(0.12) to 8.55(0.34). The CUPRAC antioxidant assay delivered values in the range from 351.93(11.85) to 1129.68(44.46) μg TE/mg DE. The FRAP method produced values from 1.27(0.03) to 6.60(0.26) μmol Fe/mg DE. The presence of gallic acid was detected in all examined samples, with lemon balm and lavender exhibiting the highest concentrations across both applied extraction methods. Notably, lavender showed especially high levels of p-hydroxybenzoic acid and chlorogenic acid. Microwave-assisted extraction generally yielded higher levels of bioactive compounds compared to infusion. These findings highlight the potential of Lamiaceae herbal extracts, particularly those obtained through microwave-assisted extraction, as valuable sources of dietary antioxidants for everyday use.

Background: Myocardial injury (MI) is characterized by an increased level of at least one cardiac troponin. Experimental MI can be induced by isoprenaline, a β-adrenergic agonist, and it can lead to heart failure (HF). Liraglutide is glucagon-like 1 peptide receptor agonist used in diabetes management, but it has anti-inflammatory and antioxidative effects, which can be beneficial in treatment of HF. The aim of this study was to investigate the effects of liraglutide on isoprenaline-induced MI and prevention of HF. Methods: Male Wistar albino rats were divided into four groups: Con—received saline the first 2 days + saline the next 7 days; Iso—isoprenaline the first 2 days + saline the next 7 days; Lir—saline the first 2 days + liraglutide the next 7 days; Iso + Lir—isoprenaline the first 2 days + liraglutide the next 7 days. On day 10, blood samples were taken for biochemical analysis and oxidative stress marker evaluation, and hearts were isolated for pathohistological analysis. Cardiac function was assessed by electrocardiography (ECG) and echocardiography (ECHO). Results: Liraglutide treatment significantly attenuated oxidative stress, repaired ECG and ECHO parameters, and mitigated myocardial morphological changes induced by isoprenaline. Conclusions: Liraglutide restores cardiac function in isoprenaline-induced HF.

The aim of this study was to determine the antidotal potential of the chlorinated oxime K870 compared to obidoxime, as a monotherapy and in combination with atropine, in paraoxon (POX)-poisoned rats. The treatment doses of oximes were chosen as 20% of their LD₅₀ values. The protective ratio (PR) of oxime K870 with atropine was significantly higher than that of obidoxime with atropine (68.8 and 125.0, respectively). In the biochemical part of the experiment POX subcutaneously (s.c.) (0.75% LD₅₀) was administered and followed by oxime K870 or obidoxime i.m. 1 min later. Acetylcholinesterase (AChE) activity was determined spectrophotometrically in cerebrum, cerebellum, brainstem, diaphragm, and erythrocytes. Carboxylesterase activity was determined in plasma and liver. Both oximes successfully reactivated AChE in brain (cerebrum, cerebellum, and brainstem), diaphragm and erythrocytes, but the oxime K870 performed better than obidoxime. Both oximes reactivated carboxylesterase, obidoxime better in plasma and oxime K870 better in liver. In conclusion, the oxime K870, when co-administered with atropine, is a more effective antidote than the obidoxime-atropine combination in POX-poisoned rats.

Background/Objectives: The importance of fixed-dose combinations (FDCs) for the treatment of hypertension is well established. However, from a stability perspective, FDCs present a challenge since the degradation of one active pharmaceutical ingredient (API) can be affected by the presence of another API. The aim of this study was to compare the degradation behaviors and evaluate the degradation kinetics of three antihypertensive drugs, perindopril tert-butylamine (PER), amlodipine besylate (AML), and indapamide (IND). Methods: The degradation processes were studied using the previously developed reverse phase high-performance liquid chromatographic (RP-HPLC) method after exposing each drug individually, as well as the combinations of two/three drugs, to different stress factors, such as light, oxidation, acidic, basic, or neutral pH values at different temperatures. Results: The results show that PER is most unstable under basic conditions and that AML displays a negative, while IND displays a positive effect, on PER stability when combined. AML is most affected by basic conditions and oxidation, and its stability is affected by both drugs positively; IND undergoes extreme photolysis, which is positively affected by AML but negatively by PER. Conclusions: Great care must be taken when formulating FDCs with these three drugs, as well as solutions or oral suspensions adjusted for geriatric or pediatric populations, since the stability of all three drugs is greatly affected by pH conditions, as well as light or oxidation factors and their interactions.

Patients suffering from cholelithiasis have an increased risk of developing cardiovascular complications, particularly ischemic myocardial disease. Ursodeoxycholic acid (UDCA), already used in clinical practice for the treatment of cholelithiasis and related conditions, has proven antioxidative, anti-inflammatory, and cytoprotective effects. Therefore, the aim of this study was to investigate the cardioprotective effect of UDCA pre-treatment on isoprenaline-induced myocardial injury in rats. Male Wistar albino rats were randomized into four groups. Animals were pre-treated for 10 days with propylene glycol + saline on days 9 and 10 (control), 10 days with propylene glycol + isoprenaline on days 9 and 10 (I group), 10 days with UDCA + saline on days 9 and 10 (UDCA group), and 10 days with UDCA + isoprenaline on days 9 and 10 (UDCA + I group). UDCA pre-treatment significantly reduced values of high-sensitivity troponin I (hsTnI) and aspartate aminotransferase (AST) cardiac markers (p < 0.001 and p < 0.01, respectively). The value of thiobarbituric acid reactive substances (TBARS) was also decreased in the UDCA + I group compared to the I group (p < 0.001). UDCA also significantly increased glutathione (GSH) levels, while showing a tendency to increase levels of superoxide dismutase (SOD) and catalase (CAT). The level of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) expression, a key regulatory gene of inflammation, was diminished when UDCA was administered. A reduction of cardiac damage was also observed in the UDCA pre-treated group. In conclusion, UDCA pre-treatment showed a cardioprotective effect on isoprenaline-induced myocardial injury in rats, primarily by reducing oxidative stress and inflammation.