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Content available remote Modulation of the human preadipocyte mitochondrial activity by beta-carotene
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EN
Increased ROS generation by the overload by metabolic substrates mitochondria paralleled by decrease of antioxidant activity are typical events found in metabolic syndrome and diabetes type 2. Metabolites of beta-carotene (BC) such as retinoic acid (RA), as well as low concentration of reactive oxygen species (ROS) modify the mitochondrial bioenergetic function. The aim of the study was to investigate the effect of beta-carotene on mitochondrial activity in human preadipocytes. BC used in concentrations, 10 or 30 µM, decreased mitochondrial membrane potential, inhibited mitochondrial respiration and decreased cellular ATP content. We conclude, that BC, the known antioxidant may decrease oxidative phosphorylation capacity of mitochondria.
EN
The effect of feeding ration, enriched in synthetic and natural ß-carotene on the selectedindicators of health condition of the cows and on reproduction parameters. The studies were conducted on 40 Simmental cows, classified into 4 groups, 10 animals in each group. The experiment was performed since the 4th week before calving until 12 week of lactation. In group I (control), standard nutrition, based on grass silage and maize silage was employed. In group II 400 mg of synthetic ß-carotene/cow/day to the ration was introduced. In group III, a part of maize silage was replaced by pumpkin silage in such ratio as to receive by 400 mg higher intake of natural ß-carotene/cow/day as compared to group I. The rations in group IV were not balanced in respect of the content of ß-carotene; there was only the replacement of 60% DM of maize silage by the pumpkin silage in this group. During the studies, blood samples were collected: to 5 hours after calving and on 4 and 12 week of lactation. Milk samples were collected on 4, 8 and 12 week of lactation and on 23 day after the first insemination. Morphological parameters of blood and concentration of ß-hydroxy-butyric acid in blood serum were analysed. In milk, somatic cell count and the level of progesterone on 23 day after insemination were determined. In group I during the following measurements were found the lowest levels of part of the morphological parameters of blood: after calving the lowest level of RBC (significant difference compared to group II), at 4th week of lactation the lowest level of HCT, and at 12 week of lactation RBC and HCT. The significant differences in somatic cell count in the milk, were recorded in the 8th week of lactation –significantly higher in group I as compared to group III. The significant differences between the groups in respect of BHM acid concentration was found only after calving. The highest BHM level occurred in the cows from group I and it was significantly higher in relation to group II and IV. In the cows from groups II, III and IV, the first heat occurred earlier; these animals had also shorter inter-gestation period. Also, the progesterone level, as determined on 23 day after insemination, was higher in the milk of cows from groups II, III and IV as compared to the animals from group I.
PL
Wpływ dawki pokarmowej wzbogaconej w syntetyczny lub naturalny β-karoten na wybrane wskaźniki stanu zdrowia krów oraz parametry rozrodu.Badania przeprowadzono na 40 krowach rasy simentale, podzielonych na 4 grupy po 10 osobników. Doświadczenie prowadzono od 4 tygodnia przed planowanym wycieleniem do 12 tygodnia laktacji. W grupie I (kontrolnej) stosowano standardowe żywienie oparte na kiszonce z traw i kiszonce z kukurydzy. W grupie II wprowadzono dodatek do dawki 400 mg syntetycznego ß-karotenu/krowę/dzień. W grupie III zastępowano część kiszonki z kukurydzy kiszonką z dyni, tak aby uzyskać w porównaniu do grupy I wyższe o 400 mg pobranie naturalnego ß-karotenu/krowę/dzień. Dawki w grupie IV nie bilansowano pod kątem zawartości β-karotenu, a przyjęto w niej zastąpienie 60% s.m. kiszonki z kukurydzy kiszonką z dyni. W trakcie badań od krów pobierano krew: do 5 godzin po wycieleniu w 4, 12 tygodniu laktacji. Próbki mleka pobierano w 4, 8 i 12 tygodniu laktacji oraz w 23 dniu po pierwszej inseminacji. Analizowano parametry morfologiczne krwi oraz w surowicy stężenie kwasu β-hydroksymasłowego. W mleku oznaczono liczbę komórek somatycznych oraz poziom progesteronu w 23 dniu po inseminacji. W grupie I podczas kolejnych pomiarów stwierdzono najniższe poziomy części parametrów morfologicznych krwi. Po wycieleniu najniższy poziom RBC (istotna różnica w stosunku do grupy II), w 4 tygodniu laktacji najniższy poziom HCT, a w 12 tygodniu laktacji RBC i HCT. Różnice między grupami w zawartości komórek somatycznych w mleku stwierdzono w 8 tygodniu laktacji - istotnie więcej w grupie I w porównaniu do III. Istotne różnice między grupami w stężeniu kwasu BHM w surowicy stwierdzono tylko po wycieleniu. Najwyższy poziom BHM występował u krów z grupy I i był istotnie wyższy w stosunku do grupy II i IV. U krów z grup II, III i IV w porównaniu do I wcześniej wystąpiła I ruja, a także miały one krótszy okres międzyciążowy. Również oznaczony w 23 dniu po inseminacji poziom progesteronu wyższy był w mleku krów z grup II, III i IV w porównaniu do krów z grupy I.
EN
The paper presents the results of experiments to determine the influence of selected physico-chemical factors – oxygen, visible light and temperature – on the decomposition of (1) chlorophylls a, b and c, chlorophyll a derivatives and β-carotene in acetone solution, and (2) chlorophyll a and β-carotene in axenic cultures of the blue-green algae Anabaena variabilis. The results indicate that both in acetone extracts and in blue-green algae cultures these pigments were most sensitive to light and oxygen; temperatures of up to 25◦C had no marked influence on these compounds. Under anoxia in acetone solution, the stability towards light decreased in the order chlorophyll a, chlorophyll b, chlorophylls c. Chlorophyll a, moreover, was less stable than its derivatives – phaeophorbides, phaeophytins, pyrophaeophytins and steryl chlorins – but more stable than β-carotene, in the last case also in the blue-green algae cultures. Decomposition of all the pigments proceeded mainly via the breakdown of the porphyrin macrocycle, since the decomposition products were not detected in the VIS range. On the basis of these experiments one can state that while light and oxygen may have a decisive direct influence on the distribution of chlorophylls and β-carotene in sediments, in the natural environment, temperatures of up to 25◦ C may have very little immediate effect.
EN
Rats were exposed to a total dose of 0.75 Gy of γ radiation from a 60Co source, receiving three doses of 0.25 Gy at weekly intervals. During two days before each irradiation, the animals received daily intragastric doses of 26 mg pantothenol or 15 mg β-carotene per kg body mass. The animals were killed after the third irradiation session, and their blood and livers were analyzed. As found previously (Slyshenkov, V.S., Omelyanchik, S.N., Moiseenok, A.G., Trebukhina, R.V. & Wojtczak, L. (1998) Free Radical Biol. Med. 24, 894-899), in livers of animals not supplied with either pantothenol or β-carotene and killed one hour after the irradiation, a large accumulation of lipid peroxidation products, as conjugated dienes, ketotrienes and thiobarbituric acid-reactive substances, could be observed. The contents of CoA, pantothenic acid, total phospholipids, total glutathione and GSH/GSSG ratio were considerably decreased, whereas the NAD/NADH ratio was increased. All these effects were alleviated in animals supplied with β-carotene and were completely abolished in animals supplied with pantothenol. In the present paper, we extended our observations of irradiation effects over a period of up to 7 days after the last irradiation session. We found that most of these changes, with the exception of GSH/GSSG ratio, disappeared spontaneously, whereas supplementation with β-carotene shortened the time required for the normalization of biochemical parameters. In addition, we found that the activities of glutathione reductase, glutathione peroxidase, catalase and NADP-dependent malate (decarboxylating) dehydrogenase ('malic enzyme') in liver were also significantly decreased one hour after irradiation but returned to the normal level within 7 days. Little or no decrease in these activities, already 1 h after the irradiation, could be seen in animals supplemented with either β-carotene or pantothenol. It is concluded that pantothenol is an excellent radioprotective agent against low-dose γ radiation.
EN
The aim of this study has been to determine the effect of a diet containing β-carotene and omega-3 fatty acids on the biochemical and nonspecific humoral immunity indicators and on the results of rearing calves to day 60 of life. The study was conducted in 2011-2012, on a herd of Polish Holstein-Friesian cows. 54 calves from the herd were divided into 3 groups, 18 animals in each: CTR, TRT1 and TRT2. During the colostral period lasting for 5 days after birth, calves were drinking the mother’s colostrum. From 6 to 60 days, calves were watered milk replacer formulation. The control group (CTR) consisted of calves after the colostral period given milk replacer formulation without any supplementation. In the two other groups, calves received milk replacers with the supplementation of b-carotene (TRT1 group) in the amount of 25 mg/calf/day or a suspension of liver omega-3 oil (TRT2 group) in the amount of 5g/calf/day. All calves received solid feed ad libitum. The research showed that the parameters of the metabolic profile of calves (ALT, ASP, CHOL, GLU, UREA, ALP, TG, CRE) were within the normal range, indicating good health of the calves. Moreover, the supplementation had a positive impact on the chosen immunological parameters, including a higher IgG concentration, especially at the end of the milk drinking period. The result of B-carotene in a diet was the highest daily gain in the period from 30 to 60 days of life among the analysed groups of calves. No such effect was achieved in the TRT2 group of calves, as their body weight was the lowest. However, noteworthy is the beneficial impact of beta-carotene and omega-3 oil on the non-specific humoral immunity parameters, which was manifested by fewer cases of clinical diarrhoea and upper respiratory tract diseases.
PL
Praca zawiera wyniki analizy chemicznej gotowych produktów sojowych badanych na zawartość wybranych witamin. Oznaczanie witaminy C, Β-karotenoidów, Β-cis-karotenu i likopenu przeprowadzono metodą wysokociśnieniowej chromatografii cieczowej (HPLC). Analiza wykazała dość wysoką zawartość witaminy C oraz Β-karotenoidów w produktach sojowych. Uzyskane wyniki oznaczeń zawierają się w górnych przedziałach zawartości witamin w produktach sojowych.
EN
This paper describes the determination of basic forms of vitamins: Β-karotenoids, Β-cis-karoten, likopen and C in soyben products using of HPLC with UV-VIS detection. Special attention was paid on influence of sample preparation on appointed content of substance - optimization of saponification conditions. Also statistical data analysis, based on soyben products analysis and relative standard deviation (RSD) for both vitamins was performed.
PL
Celem pracy było zbadanie wpływu ß-karotenu na poziom α- i δ-tokoferoli w próbach, przy użyciu triacylogliceroli smalcu jako substratu. Dodatkowo zbadano skuteczność przeciwutleniającą tych związków. Stwierdzono, że rozkład tokoferoli w przechowywanym smalcu zależał nie tylko od ilości nadtlenków, ale był szybszy przy ich niższych stężeniach w substracie i większym dodatku ß-karotenu.
EN
The aim of the work was to examine ß-carotene as a synergist added in two doses to α and δ-tocopherol. As well as determine its antioxidant activity. The experiment was performed using pork lard as a triaciloglicerol substrate. It was found that tocopherol disintegration in lard depends on quantity of peroxide and it is faster as its concentration in substrate is lower and higher amount of ß-carotene is added.
EN
DNA methylation is a potent regulator of gene expression. The influence of beta-carotene (BC) and arachidonic acid (AA) on angiogenesis - a new blood vessel formation, was reported. The tyrosine kinase VEGFR-2 receptor (KDR) activation by vascular endothelial growth factor is one of the main angiogenic mechanisms. This study was aimed to investigate a possible role of CpG island methylation on regulation of the pro-angiogenic KDR gene expression after incubation of human endothelial cells with BC and/or AA. Methods: Human umbilical vein endothelial cells (HUVEC) were incubated with BC (1-10 µM) and/or 3 µM AA for 24 hours. The CpG island methylation was quantified using the COBRA method and restriction enzymes' digestion (NewEngland BioLabs). Intracellular protein concentrations were determined by Western blot analysis using the specific antibodies (Santa Cruz). Results: Incubation with BC and AA, decreased methylation of the KDR promoter region. These results well-correlated with the detected, by qRT-PCR, up-regulation of KDR gene expression by BC (p=0.035) as well as by AA. Incubation with BC (p=0.02) and AA (p=0.0014) increased the KDR protein levels in HUVECs. Conclusion: The changes in CpG island methylation of the KDR the pro-angiogenic gene promoter, represents one of the mechanisms involved in regulation of angiogenic response by BC and AA.
EN
The influence of UVA and VIS radiation on the β-carotene biosynthesis by yeast Rhodotorula mucilaginosa was studied. The impact of radiation characteristic on biomass growth, substrate consumption and β-carotene production in submerged batch culture in bioreactor was studied. Three different types of light sources were used in the experiment: VIS – 15 W, wavelength range from 400 to 800 nm, the largest emission at 420 nm; UVA – 18 W, blue light, wavelength range of 350 to 430 nm, the largest emission at 370 nm; UVA – 20 W, wavelength range from 350 to 575 nm, the largest emission at 350 nm. In cultures conducted with UVA – 18 W radiation the highest β-carotene and carotenoids cellular concentration were achieved, respectively 63.20 μg/gd.w. and 0.97 mg/gd.w.. In cultures subject to VIS radiation a lower β-carotene concentration at 43.60 μg/gd.w. and the total carotenoids concentration at 0.83 mg/gd.w. was obtained. The ultraviolet radiation with the emission peak of radiation at 370 nm promoted the β-carotene and carotenoids production in yeast Rhodotorula mucilaginosa.
PL
Badano wpływ promieniowania UVA i VIS na biosyntezę β-karotenu przez drożdże Rhodotorula mucilaginosa. Określano wpływ promieniowania charakterystycznego na wzrost biomasy, zużycie substratu i produkcję β-karotenu we wgłębnej hodowli okresowej prowadzonej w bioreaktorze. Zastosowano trzy różne rodzaje źródeł światła: VIS – 15 W, zakres długości fali od 400 do 800 nm, największa emisja przy 420 nm; UVA1 – 18 W, zakres długości fali od 350 do 430 nm, największa emisja przy 370 nm; UVA2 – 20 W, zakres długości fali od 350 do 575 nm, największa emisja przy 350 nm. W kulturach prowadzonych za pomocą promieniowania UVA otrzymano najwyższe stężenie β-karotenu i karotenoidów, odpowiednio 63,20 μg/gs.m. i 0,97 mg/gs.m. W hodowlach napromieniowanych lampą VIS uzyskano niższe stężenie β-karotenu (43,60 μg/gs.m) i karotenoidów (0,83 mg/gs.m). Promieniowanie ultrafioletowe ze szczytem emisji promieniowania przy 370 nm promowało produkcję β-karotenu i karotenoidów w komórkach drożdży Rhodotorula mucilaginosa.
PL
W pracy otrzymano etylopochodną δ-tokoferolu metodą chloroalkilacji celem ustalenia jej skuteczności w stosunku do ß-karotenu. Praca jest kontynuacją badań nad oceną właściwości przeciwutleniających etylowej pochodnej δ-tokoferolu - przebadano zmiany liczby nadtlenkowej prób smalcu z dodatkiem tokoferoli i pochodnej δ-tokoferolu, a także określono rozpad antyoksydantów podczas przechowywania prób smalcu.
EN
The aim of this work was to develop new antioxidants. Synthesis of δ-tocopherol was carried out which yielded ethyl-δ-tocopherol. The effect of addition of the antioxidant on β-carotene was tested by a modified Bickoff test. It was found that the antioxidant activity of the new δ-tocopherol toward β-carotene was lower than that of δ- and y-tocopherols.
EN
 When we investigated the genotoxicity of β-carotene cleavage products (CPs) in primary rat hepatocytes stimulated to proliferate, we observed dose-dependent increases of chromosomal aberrations, sister chromatid exchanges and micronuclei. In contrast to other genotoxic substances, however, this increased genotoxicity was not accompanied by increased cytotoxicity. As a consequence we observed metaphases showing massive chromosomal damage, indicating inhibition of apoptosis by CPs enabling these cells to proceed in the cell cycle. Since proliferative stimulation by growth factors may support this effect, the in vitro toxicological effects of CPs were studied on proliferatively quiescent primary rat hepatocytes. A significant increase of both apoptosis and necrosis was found. Supplementation with antioxidants did not significantly lower the level of apoptosis, while the level of necrosis was significantly reduced by Trolox and N-acetylcysteine at all concentrations tested as well as ascorbic acid (50 μM) and a combination of Trolox (50 μM) and ascorbic acid (50 μM). These observations indicate that a) the cytotoxic potential in combination with the genotoxic potential of CPs may promote the initiation of cells due to compensatory cell division in exposed tissues and may aggravate inflammatory processes under chronic exposure, and b) the applied antioxidants may protect from cytotoxicity primarily via the detoxification of aldehydic β-carotene cleavage products.
EN
This study was aimed at comparing the stability of carotenes (α- and β-carotene) in oil solutions with their stability when spray-dried encapsulation is applied. The carotenes were isolated from carrot. A storage test was subsequently performed. The stability of carotenes in oil solutions was determined with the HPLC method. The color of the samples was also analyzed. The oil solutions of carotenes were microencapsulated with the spray-drying method. A mixture of gum Arabic and maltodextrin was used as a matrix. Degradation of carotenes during storage of the oil solutions followed first-order kinetics. The energies of activation were 58.7 and 33.6 kJ/mol for α- and β-carotene, respectively. Among the studied factors (time, daylight, temperature), it was the time and the temperature that infl uenced carotenes degradation the most. Spray-drying encapsulation caused a signifi cant decrease in the content of carotenes. However, retention of pigments stored in microspheres was longer than retention of pigments stored as oil solutions.
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