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result(s) for
"Pugovics, Osvalds"
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Plasma acylcarnitine concentrations reflect the acylcarnitine profile in cardiac tissues
by
Vilks, Karlis
,
Makrecka-Kuka, Marina
,
Kuka, Janis
in
101/58
,
631/443/319/2723
,
631/45/287/1183
2017
Increased plasma concentrations of acylcarnitines (ACs) are suggested as a marker of metabolism disorders. The aim of the present study was to clarify which tissues are responsible for changes in the AC pool in plasma. The concentrations of medium- and long-chain ACs were changing during the fed-fast cycle in rat heart, muscles and liver. After 60 min running exercise, AC content was increased in fasted mice muscles, but not in plasma or heart. After glucose bolus administration in fasted rats, the AC concentrations in plasma decreased after 30 min but then began to increase, while in the muscles and liver, the contents of medium- and long-chain ACs were unchanged or even increased. Only the heart showed a decrease in medium- and long-chain AC contents that was similar to that observed in plasma. In isolated rat heart, but not isolated-contracting mice muscles, the significant efflux of medium- and long-chain ACs was observed. The efflux was reduced by 40% after the addition of glucose and insulin to the perfusion solution. Overall, these results indicate that during fed-fast cycle shifting the heart determines the medium- and long-chain AC profile in plasma, due to a rapid response to the availability of circulating energy substrates.
Journal Article
Purchasing “Nootropics” Online: Identification and Quantification of Ingredients in Phenibut-Containing Products
by
Kazoka, Helena
,
Kisis, Vadims
,
Upmanis, Toms
in
Agonists
,
Chemical properties
,
Chromatography
2024
Background and Objectives: Phenibut is a central nervous system drug that is registered and used in clinical practice as a prescription medication. In recent decades, the drug has become popular as a “nootropic and cognition enhancer” because of its active marketing as a dietary or food supplement sold online. This has resulted in a growing number of case reports on acute toxicity and withdrawal symptoms and has raised concerns about the quality of phenibut-containing products. Materials and Methods: We used high-performance liquid chromatography with diode-array detection and ultra-performance liquid chromatography–mass spectrometry to investigate the quality of six phenibut-containing samples purchased from three internet suppliers. Results: Substantially lower levels of the active pharmaceutical ingredient than claimed on the packaging were found for three of the supplements tested. A considerably higher level of phenibut was present in one product. All online-purchased phenibut-containing capsules included declared and undeclared ingredients found in various dietary supplements claiming to have metabolic, neurotropic, antioxidant, anti-inflammatory, and neuroprotective properties. Conclusions: The online-purchased phenibut products contained undeclared ingredients and the content of phenibut differed from the declared. The combinations of these additional ingredients with phenibut have not been tested for activity or safety and their use warrants further attention to avoid potential health problems.
Journal Article
Phenolic Content and Anti-Inflammatory Activity of Cultivated and Wild-Type Galium odoratum Extracts in Murine Bone Marrow-Derived Macrophages
2024
Galium odoratum, commonly known as sweet woodruff, is a perennial herbaceous plant that contains coumarin and is recognized for its medicinal properties. In this study, the influence of sunlight exposure on the phytochemical composition and anti-inflammatory potential of G. odoratum extracts is assessed. The extracts from cultivated and wild-grown plants were analyzed via chromatographic and mass spectrometric methods. In addition, the total phenolic content, antioxidant activity, and effects on macrophage polarization were assessed. The results revealed that while coumarin levels remain stable regardless of environmental conditions, phenolic content and antioxidant activity increase significantly under sun-grown conditions, with chlorogenic acid and rutin identified as major contributing compounds. Additionally, the extracts exhibited anti-inflammatory activity, effectively reducing the M1 macrophage population involved in inflammatory responses. These findings suggest that controlled sunlight exposure can enhance the bioactive profile of G. odoratum. This research highlights the critical role of environmental management in optimizing the medicinal properties of G. odoratum, providing a foundation for its future use in natural therapeutic applications.
Journal Article
The Cultivation of Chelidonium majus L. Increased the Total Alkaloid Content and Cytotoxic Activity Compared with Those of Wild-Grown Plants
by
Sile, Inga
,
Krizhanovska, Valerija
,
Grinberga, Solveiga
in
Alkaloids
,
Biological activity
,
Cancer
2021
The effect of cultivation practises on both the phytochemical profile and biological activity of aqueous ethanol extracts of Chelidonium majus L. was studied. Extracts were prepared from aerial parts of the same plant population collected in the wild and grown under organic farming conditions. Both qualitative and quantitative analyses of alkaloids and flavonoid derivatives were performed by LC/MS methods, and the cytotoxicity of lyophilised extracts was studied in B16-F10, HepG2, and CaCo-2 cells. Coptisine was the dominant alkaloid of extracts prepared from wild-grown plants, whereas after cultivation, chelidonine was the most abundant alkaloid. The total alkaloid content was significantly increased by cultivation. Ten flavonol glycoconjugates were identified in C. majus extracts, and quantitative analysis did not reveal significant differences between extracts prepared from wild-grown and cultivated specimens. Treatment with C. majus extracts resulted in a dose-dependent increase in cytotoxicity in all three cell lines. The extracts prepared from cultivated specimens showed higher cytotoxicity than the extracts prepared from wild-grown plants. The strongest cytotoxic effect of cultivated C. majus was observed in B16-F10 cells (IC50 = 174.98 ± 1.12 µg/mL). Cultivation-induced differences in the phytochemical composition of C. majus extracts resulted in significant increases in the cytotoxic activities of the preparations.
Journal Article
Wild-Grown and Cultivated Glechoma hederacea L.: Chemical Composition and Potential for Cultivation in Organic Farming Conditions
by
Sile, Inga
,
Kalane, Laura
,
Vecvanags, Alekss
in
Acids
,
Anti-inflammatory agents
,
Anticancer properties
2022
Glechoma hederacea L. is a medicinal plant that is known in traditional medicine for its anti-inflammatory, antibacterial, antiviral, and anticancer properties. This study evaluated the potential for commercial production of G. hederacea and compared the chemical composition and activity of 70% ethanol extracts and steam-distilled essential oils from wild-grown and cultivated G. hederacea collected in different harvesting periods. The main compounds identified in the 70% ethanol extracts were phenolic acids (chlorogenic and rosmarinic acids) and flavonoid O-glycosides. The essential oil varied in the three accessions in the range of 0.32–2.98 mL/kg−1 of dry weight. The extracts possessed potent antioxidant and anti-inflammatory properties in LPS-treated bone-marrow-derived macrophages. The results of flow cytometry show that extracts from different vegetation periods reduced the conversion of macrophages to the proinflammatory phenotype M1. The chemical composition varied the most with the different harvesting periods, and the most suitable periods were the flowering and vegetative phases for the polyphenolic compounds and essential oils, respectively. G. hederacea can be successfully grown under organic farming conditions, and cultivation does not significantly affect the chemical composition and biological activity compared to wild-grown plants.
Journal Article
Long-chain acylcarnitine content determines the pattern of energy metabolism in cardiac mitochondria
2014
In the heart, a nutritional state (fed or fasted) is characterized by a unique energy metabolism pattern determined by the availability of substrates. Increased availability of acylcarnitines has been associated with decreased glucose utilization; however, the effects of long-chain acylcarnitines on glucose metabolism have not been previously studied. We tested how changes in long-chain acylcarnitine content regulate the metabolism of glucose and long-chain fatty acids in cardiac mitochondria in fed and fasted states. We examined the concentrations of metabolic intermediates in plasma and cardiac tissues under fed and fasted states. The effects of substrate availability and their competition for energy production at the mitochondrial level were studied in isolated rat cardiac mitochondria. The availability of long-chain acylcarnitines in plasma reflected their content in cardiac tissue in the fed and fasted states, and acylcarnitine content in the heart was fivefold higher in fasted state compared to the fed state. In substrate competition experiments, pyruvate and fatty acid metabolites effectively competed for the energy production pathway; however, only the physiological content of acylcarnitine significantly reduced pyruvate and lactate oxidation in mitochondria. The increased availability of long-chain acylcarnitine significantly reduced glucose utilization in isolated rat heart model and in vivo. Our results demonstrate that changes in long-chain acylcarnitine contents could orchestrate the interplay between the metabolism of pyruvate–lactate and long-chain fatty acids, and thus determine the pattern of energy metabolism in cardiac mitochondria.
Journal Article
Peptide/β-Peptoid Hybrids with Ultrashort PEG-Like Moieties: Effects on Hydrophobicity, Antibacterial Activity and Hemolytic Properties
by
Frederiksen, Nicki
,
Louka, Stavroula
,
Tomczak, Magdalena
in
Amino acids
,
Antibiotics
,
Antimicrobial agents
2021
PEGylation of antimicrobial peptides as a shielding tool that increases stability toward proteolytic degradation typically leads to concomitant loss of activity, whereas incorporation of ultrashort PEG-like amino acids (sPEGs) remains essentially unexplored. Here, modification of a peptide/β-peptoid hybrid with sPEGs was examined with respect to influence on hydrophobicity, antibacterial activity and effect on viability of mammalian cells for a set of 18 oligomers. Intriguingly, the degree of sPEG modification did not significantly affect hydrophobicity as measured by retention in reverse-phase HPLC. Antibacterial activity against both wild-type and drug-resistant strains of Escherichia coli and Acinetobacter baumannii (both Gram-negative pathogens) was retained or slightly improved (MICs in the range 2–16 µg/mL equal to 0.7–5.2 µM). All compounds in the series exhibited less than 10% hemolysis at 400 µg/mL. While the number of sPEG moieties appeared not to be clearly correlated with hemolytic activity, a trend toward slightly increased hemolytic activity was observed for analogues displaying the longest sPEGs. In contrast, within a subseries the viability of HepG2 liver cells was least affected by analogues displaying the longer sPEGs (with IC50 values of ~1280 µg/mL) as compared to most other analogues and the parent peptidomimetic (IC50 values in the range 330–800 µg/mL).
Journal Article
L-Carnitine Supplementation Increases Trimethylamine-N-Oxide but not Markers of Atherosclerosis in Healthy Aged Women
by
Grinberga, Solveiga
,
Pugovics, Osvalds
,
Sawicka, Angelika K.
in
Adhesion
,
Aged
,
Arteriosclerosis
2019
Background: L-carnitine can be metabolized to trimethylamine N-oxide (TMAO), a molecule that promotes atherogenesis through its interaction with macrophages and lipid metabolism. Objective: The aim of the present study was to assess whether L-carnitine supplementation may promote changes in selected serum biomarkers of atherosclerosis. Methods: Before the start, in the mid-point and after completing the 24-weeks supplementation protocol, fasting blood samples were taken from the antecubital vein. Plasma free L-carnitine and TMAO were determined by the UPLC/MS/MS method. Serum proteins were determined by the enzyme immunoassay method using commercially available kits. Total cholesterol, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol, and triglycerides have been determined using standard automatic analyzer. Results: L-carnitine supplementation elevated fasting plasma carnitine in the mid-point of our study and it remained increased until the end of supplementation period. Moreover, it induced tenfold increase in plasma TMAO concentration but did not affect serum C-reactive protein, interleukin-6, tumour necrosis factor-α, L-selectin, P-selectin, vascular cell adhesion molecule-1, intercellular adhesion molecule-1 or lipid profile markers. Conclusion: We demonstrated that although oral L-carnitine supplementation significantly increased plasma TMAO concentration, no lipid profile changes or other markers of adverse cardiovascular events were detected in healthy aged women over the period of 24 weeks.
Journal Article
Increased Trimethylamine N-Oxide Is Not Associated with Oxidative Stress Markers in Healthy Aged Women
by
Samulak, Joanna Jolanta
,
Olek, Robert Antoni
,
Grinberga, Solveiga
in
Aged
,
Atherosclerosis
,
Biomarkers
2019
Increased plasma trimethylamine N-oxide (TMAO) levels have been associated with cardiovascular diseases (CVD). L-carnitine induces TMAO elevation in human blood, and thus, it has been suggested as developing atherosclerosis. The aim of this study was to determine the relation between selected markers of oxidative stress and plasma TMAO concentration induced by L-carnitine supplementation for 24 weeks in healthy aged women. Twenty aged women were supplemented during 24 weeks with either 1500 mg L-carnitine-L-tartrate (n=11) or isonitrogenous placebo (n=9) per day. Fasting blood samples were taken from antecubital vein. L-carnitine supplementation induced an increase in TMAO, but not in γ-butyrobetaine (GBB). Moreover, there were no significant changes in serum ox-LDL, myeloperoxidase, protein carbonyls, homocysteine, and uric acid concentrations due to supplementation. Significant reduction in white blood cell counts has been observed following 24-week supplementation, but not attributable to L-carnitine. Our results in healthy aged women indicated no relation between TMAO and any determined marker of oxidative stress over the period of 24 weeks. At the same time, plasma GBB levels were not affected by L-carnitine supplementation. Further clinical studies of plasma GBB level as a prognostic marker are needed.
Journal Article
Efficacy of Proanthocyanidins from Pelargonium sidoides Root Extract in Reducing P. gingivalis Viability While Preserving Oral Commensal S. salivarius
by
Basevičiene, Nomeda
,
Savickiene, Nijole
,
Pugovics, Osvalds
in
Antibiotics
,
Antioxidants
,
Biofilms
2018
Bacterial resistance to antibiotics and the disruption of beneficial microbiota are key problems in contemporary medicine and make the search for new, more efficient infection treatment strategies among the most important tasks in medicine. Multicomponent plant-derived preparations with mild antibacterial activity created by many simultaneous mechanisms together with anti-inflammatory, innate immune and regenerative capacity-stimulating properties are good candidates for this therapy, and proanthocyanidins are among the most promising compounds of this sort. In this study, we have isolated proanthocyanidins from Pelargonium sidoides DC root extract and characterized and compared the composition, antioxidant properties and antibacterial activity of the proanthocyanidin fraction with those of the whole extract. The results revealed that proanthocyanidins had significantly stronger antioxidant capacity compared to the root extract and exhibited a unique antibacterial action profile that selectively targets Gram-negative keystone periodontal and peri-implant pathogenic strains, such as Porphyromonas gingivalis, while preserving the viability of beneficial oral commensal Streptococcus salivarius. The finding suggests that proanthocyanidins from Pelargonium sidoides root extract are good candidates for the prolonged and harmless treatment of infectious diseases.
Journal Article