The aim of this study was to develop multifunctional magnetic poly(ε-caprolactone) (PCL) mats with antibacterial properties for bone tissue engineering and osteosarcoma prevention. To provide good dispersion of magnetic iron oxide nanoparticles (IONs), they were first grafted with PCL using a novel three-step approach. Then, a series of PCL-based mats containing a fixed amount of ION@PCL particles and an increasing content of ascorbic acid (AA) was prepared by electrospinning. AA is known for increasing osteoblast activity and suppressing osteosarcoma cells. Composites were characterized in terms of morphology, mechanical properties, hydrolytic stability, antibacterial performance, and biocompatibility. AA affected both the fiber diameter and the mechanical properties of the nanocomposites. All produced mats were nontoxic to rat bone marrow-derived mesenchymal cells; however, a composite with 5 wt.% of AA suppressed the initial proliferation of SAOS-2 osteoblast-like cells. Moreover, AA improved antibacterial properties against Staphylococcus aureus and Escherichia coli compared to PCL. Overall, these magnetic composites, reported for the very first time, can be used as scaffolds for both tissue regeneration and osteosarcoma prevention.
- MeSH
- antibakteriální látky chemie farmakologie MeSH
- Escherichia coli účinky léků MeSH
- kosti a kostní tkáň MeSH
- krysa rodu rattus MeSH
- kyselina askorbová * chemie farmakologie MeSH
- lidé MeSH
- magnetické nanočástice chemie MeSH
- nádorové buněčné linie MeSH
- nanokompozity chemie MeSH
- osteoblasty metabolismus cytologie MeSH
- osteosarkom patologie MeSH
- polyestery * chemie MeSH
- Staphylococcus aureus * účinky léků růst a vývoj MeSH
- testování materiálů MeSH
- tkáňové inženýrství * MeSH
- tkáňové podpůrné struktury chemie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Hepatic fibrosis progresses concomitantly with a variety of biomechanical alternations, especially increased liver stiffness. These biomechanical alterations have long been considered as pathological consequences. Recently, growing evidence proposes that these alternations result in the fibrotic biomechanical microenvironment, which drives the activation of hepatic stellate cells (HSCs). Here, an inorganic ascorbic acid-oxidase (AAO) mimicking nanozyme loaded with liquiritigenin (LQ) is developed to trigger remodeling of the fibrotic biomechanical microenvironment. The AAO mimicking nanozyme is able to consume intracellular ascorbic acid, thereby impeding collagen I deposition by reducing its availability. Simultaneously, LQ inhibits the transcription of lysyl oxidase like 2 (LOXL2), thus impeding collagen I crosslinking. Through its synergistic activities, the prepared nanosystem efficiently restores the fibrotic biomechanical microenvironment to a near-normal physiological condition, promoting the quiescence of HSCs and regression of fibrosis. This strategy of remodeling the fibrotic biomechanical microenvironment, akin to "pulling the rug out from under", effectively treats hepatic fibrosis in mice, thereby highlighting the importance of tissue biomechanics and providing a potential approach to improve hepatic fibrosis treatment.
- MeSH
- biomechanika MeSH
- buněčné mikroprostředí účinky léků MeSH
- flavanony farmakologie chemie MeSH
- jaterní cirhóza * farmakoterapie metabolismus patologie MeSH
- jaterní hvězdicovité buňky * metabolismus cytologie účinky léků MeSH
- kolagen typu I metabolismus MeSH
- kyselina askorbová * farmakologie metabolismus chemie MeSH
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Crops, such as white cabbage (Brassica oleracea L. var. capitata (L.) f. alba), are often infested by herbivorous insects that consume the leaves directly or lay eggs with subsequent injury by caterpillars. The plants can produce various defensive metabolites or free radicals that repel the insects to avert further damage. To study the production and effects of these compounds, large white cabbage butterflies, Pieris brassicae and flea beetles, Phyllotreta nemorum, were captured in a cabbage field and applied to plants cultivated in the lab. After insect infestation, leaves were collected and UV/Vis spectrophotometry and HPLC used to determine the content of stress molecules (superoxide), primary metabolites (amino acids), and secondary metabolites (phenolic acids and flavonoids). The highest level of superoxide was measured in plants exposed to fifty flea beetles. These plants also manifested a higher content of phenylalanine, a substrate for the synthesis of phenolic compounds, and in activation of total phenolics and flavonoid production. The levels of specific phenolic acids and flavonoids had higher variability when the dominant increase was in the flavonoid, quercetin. The leaves after flea beetle attack also showed an increase in ascorbic acid which is an important nutrient of cabbage.
Nutritional value and disease-preventive effects of cabbage are well-known. Levels of the antioxidant compounds ascorbic acid (AA) and glucosinolates (GSL) in new Czech cabbage cultivars were determined in the context of different production systems. The contents of AA and GSLs in cabbage biomass were determined by HPLC. Individual GSLs were identified according to their exact masses with sinigrin used as the external standard. Artificial infection with A. brassicicola generally raised the AA levels. The major GSLs (≥10 mg kg-1) were glucobrassicin, sinigrin, and glucoiberin. Indole and aliphatic GSLs were present, but no aromatic ones were detected. Ecological growth conditions and the artificial fungal infection increased the total content of GSLs and, also, of the methoxylated indole GSLs. Sulforaphane, iberin, indole-3-carbinol, and ascorbigen resulting from the hydrolysis of GSLs were found in both cultivars. The amounts and profiles of GSLs present in the two Czech cultivars demonstrated their good nutritional value. The decomposition products sulforaphane, iberin, indole-3-carbinol, and ascorbigen detected improve its health-promoting qualities and represent a suitable component of the human diet.
- MeSH
- antioxidancia chemie metabolismus MeSH
- Brassica chemie mikrobiologie MeSH
- glukosinoláty chemie metabolismus MeSH
- houby fyziologie MeSH
- kyselina askorbová chemie metabolismus MeSH
- lidé MeSH
- rostlinné extrakty chemie metabolismus MeSH
- životní prostředí MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
Maghemite (gamma-Fe2O3) nanoparticles, 12 nm in size, were prepared by co-precipitation of Fe(II) and Fe(III) chlorides with ammonium hydroxide and oxidation with hydrogen peroxide. To achieve stability and biocompatibility, obtained particles were coated with silica, to which glucose and ascorbic acid were bound by different mechanisms. The composite particles were thoroughly characterized by transmission electron microscopy, dynamic light scattering, elemental analysis, and FT-Raman and fluorescence spectroscopy to determine composition, morphology, size and its distribution, zeta-potential, and scavenging of peroxyl and hydroxyl radicals. As the particles showed promising antioxidative properties, they may have a possible application as a stable magnetically controlled scavenger of reactive oxygen species.
Berries, especially members of several families, such as Rosaceae (strawberry, raspberry, blackberry), and Ericaceae (blueberry, cranberry), belong to the best dietary sources of bioactive compounds (BAC). They have delicious taste and flavor, have economic importance, and because of the antioxidant properties of BAC, they are of great interest also for nutritionists and food technologists due to the opportunity to use BAC as functional foods ingredients. The bioactive compounds in berries contain mainly phenolic compounds (phenolic acids, flavonoids, such as anthocyanins and flavonols, and tannins) and ascorbic acid. These compounds, either individually or combined, are responsible for various health benefits of berries, such as prevention of inflammation disorders, cardiovascular diseases, or protective effects to lower the risk of various cancers. In this review bioactive compounds of commonly consumed berries are described, as well as the factors influencing their antioxidant capacity and their health benefits.
- MeSH
- anthokyaniny chemie MeSH
- antioxidancia chemie MeSH
- brusnice s jedlými plody chemie MeSH
- Ericaceae chemie MeSH
- fenoly chemie MeSH
- flavonoidy chemie MeSH
- jahodník chemie MeSH
- kyselina askorbová chemie MeSH
- ovoce MeSH
- Rosaceae chemie MeSH
- Rubus chemie MeSH
- Vaccinium macrocarpon chemie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
Mitochondrial oxidative damage contributes to a wide range of pathologies. One therapeutic strategy to treat these disorders is targeting antioxidants to mitochondria by conjugation to the lipophilic triphenylphosphonium (TPP) cation. To date only hydrophobic antioxidants have been targeted to mitochondria; however, extending this approach to hydrophilic antioxidants offers new therapeutic and research opportunities. Here we report the development and characterization of MitoC, a mitochondria-targeted version of the hydrophilic antioxidant ascorbate. We show that MitoC can be taken up by mitochondria, despite the polarity and acidity of ascorbate, by using a sufficiently hydrophobic link to the TPP moiety. MitoC reacts with a range of reactive species, and within mitochondria is rapidly recycled back to the active ascorbate moiety by the glutathione and thioredoxin systems. Because of this accumulation and recycling MitoC is an effective antioxidant against mitochondrial lipid peroxidation and also decreases aconitase inactivation by superoxide. These findings show that the incorporation of TPP function can be used to target polar and acidic compounds to mitochondria, opening up the delivery of a wide range of bioactive compounds. Furthermore, MitoC has therapeutic potential as a new mitochondria-targeted antioxidant, and is a useful tool to explore the role(s) of ascorbate within mitochondria.
- MeSH
- antioxidancia chemie farmakologie MeSH
- jaterní mitochondrie účinky léků metabolismus MeSH
- krysa rodu rattus MeSH
- kyselina askorbová chemie farmakologie MeSH
- oxidace-redukce MeSH
- oxidační stres účinky léků MeSH
- potkani Wistar MeSH
- systémy cílené aplikace léků metody MeSH
- vysokoúčinná kapalinová chromatografie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The aim of the study was the comparison of photo-activity of three types of titanium dioxide (TiO2) micro-dispersions intended for use as UV filters for cosmetic sunscreen products. The dispersions were also investigated with regard to their influence on the stability of photo-protective systems in cosmetic emulsions, their skin penetration/absorption and their photo-toxicity for humans and skin bacterial flora. All the tested micro-dispersions of rutile TiO2 type (agglomerates with diameter 120-150 nm), with primary particle size lower than 100 nm, demonstrated no phototoxic effect and insignificant antimicrobial behaviour. On the other hand, TiO2 with insufficient deactivation of photo-activity had significant negative impact on the stability of other organic UV filters and therefore on the stability of declared UV protective factors (SPF, UVA-PF). The study demonstrated that the level of deactivation of TiO2 is one of the highly important factors for evaluation of UV filters used as sunscreens.
- MeSH
- antibakteriální látky * chemie farmakologie účinky záření MeSH
- azosloučeniny chemie MeSH
- barvicí látky chemie MeSH
- benzensulfonáty chemie MeSH
- buňky 3T3 MeSH
- chemie farmaceutická MeSH
- Escherichia coli účinky léků MeSH
- kožní absorpce MeSH
- kůže metabolismus MeSH
- kyselina askorbová chemie MeSH
- myristáty chemie MeSH
- myši MeSH
- nanočástice * chemie účinky záření MeSH
- prasata MeSH
- přípravky chránící proti slunci * chemie farmakologie účinky záření MeSH
- Staphylococcus epidermidis účinky léků MeSH
- techniky in vitro MeSH
- titan * chemie farmakologie účinky záření MeSH
- ultrafialové záření MeSH
- velikost částic MeSH
- voda chemie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Various nitric oxide modulators (NO donors--SNP, GSNO, DEA NONOate and scavengers--PTIO, cPTIO) were tested to highlight the role of NO under Cd excess in various ontogenetic stages of chamomile (Matricaria chamomilla). Surprisingly, compared to Cd alone, SNP and PTIO elevated Cd uptake (confirmed also by PhenGreen staining) but depleted glutathione (partially ascorbic acid) and phytochelatins PC2 and PC3 in both older plants (cultured hydroponically) and seedlings (cultured in deionised water). Despite these anomalous impacts, fluorescence staining of NO and ROS confirmed predictable assumptions and revealed reciprocal changes (decrease in NO but increase in ROS after PTIO addition and the opposite after SNP application). Subsequent tests using alternative modulators and seedlings confirmed changes to NO and ROS after application of GSNO and DEA NONOate as mentioned above for SNP while cPTIO altered only NO level (depletion). On the contrary to SNP and PTIO, GSNO, DEA NONOate and cPTIO did not elevate Cd content and phytochelatins (PC2, PC3) were rather elevated. These data provide evidence that various NO modulators are useful in terms of NO and ROS manipulation but interactions with intact plants affect metal uptake and must therefore be used with caution. In this view, cPTIO and DEA NONOate revealed the less pronounced side impacts and are recommended as suitable NO scavenger/donor in plant physiological studies under Cd excess.
- MeSH
- antioxidancia chemie MeSH
- cyklické N-oxidy chemie MeSH
- donory oxidu dusnatého chemie MeSH
- fluorescenční mikroskopie MeSH
- glutathion chemie MeSH
- heřmánek, heřmánkovec, rmen, rmenec účinky léků MeSH
- imidazoly chemie MeSH
- kadmium chemie MeSH
- konfokální mikroskopie MeSH
- kyselina askorbová chemie MeSH
- nitroprusid chemie MeSH
- oxid dusnatý chemie MeSH
- reaktivní formy kyslíku chemie MeSH
- S-nitrosoglutathion chemie MeSH
- semena rostlinná účinky léků MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
This work describes a comparison of three types of commercial high-performance liquid chromatography silica monolithic columns with different inner diameters and generations of monolithic sorbent: a "classic" monolithic column, the first generation (Onyx™ monolithic C(18), 100 mm × 4.6 mm, Phenomenex); a "narrow" monolithic column for fast separation at lower flow rates (Chromolith® Performance RP-18e, 100 mm × 3 mm, Merck); and a recently introduced "high-resolution" monolithic column, the next generation (Chromolith® HighResolution RP-18e, 100 mm × 4.6 mm, Merck). Separation efficiency (number of theoretical plates, height equivalent to a theoretical plate and van Deemter curves), working pressure, the symmetry factor and resolution were critical aspects of the comparison in the case of the separation of ascorbic acid, paracetamol and caffeine. The separations were performed under isocratic conditions with a mobile phase consisting of 10:90 (v/v) acetonitrile-phosphoric acid (pH 2.80). Detailed comparison of the newest-generation monolithic column (Chromolith® HighResolution) with the previously introduced monolithic sorbents was performed and proved the advantages of the Chromolith® HighResolution column.
- MeSH
- adsorpce MeSH
- kofein chemie izolace a purifikace MeSH
- kyselina askorbová chemie izolace a purifikace MeSH
- paracetamol chemie izolace a purifikace MeSH
- vysokoúčinná kapalinová chromatografie přístrojové vybavení metody MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
