Iron is the crucial element for living organisms and its deficiency is described as the most common nutritional disorder all over the world. Nowadays, more effective and safe iron supplementation ...strategies for both humans and animals become one of the most important challenges in the therapy of nutritional deficiencies. Our previous in vivo studies confirmed safety and biodegradability of in-house manufactured zinc oxide-based nanoparticles and their rapid distribution to majority of organs and tissues in the body. In vitro examinations performed on Caco-2 cell line, a model of epithelial cells of the gastrointestinal tract, revealed a low toxicity of studied nanomaterials. In the current study, we investigated biodegradable zinc oxide nanoparticles doped with Fe(III) as a perspective supplementation strategy for iron deficiency. Biodegradable ZnO:Fe nanoparticles were intra-gastrically administered to adult mice and following 24 h, animals were sacrificed with collection of internal organs for further analyses. The iron concentration measured with atomic absorption spectrometry and histological staining (Perl’s method) showed a rapid distribution of iron-doped nanoparticles to tissues specifically related with iron homeostasis. Accumulation of iron was also visible within hepatocytes and around blood vessels within the spleen, which might indicate the transfer of Fe-doped nanoparticles from the bloodstream into the tissue. Reassuming, preliminary results obtained in the current study suggest that biodegradable ZnO nanoparticles doped with Fe might be a good carriers of exogenous iron in the living body. Therefore, subsequent investigations focus on determination an exact mechanisms related with an iron deposition in the tissue and influence of nanoparticle carriers on iron metabolism are required.
Iron and oxygen (O2) are intimately associated in many well characterized patho-physiological processes. These include oxidation of the 4Fe-4S cluster of mitochondrial aconitase and inactivation of ...this Krebs cycle enzyme by the superoxide anion (O2⋅¯), a product of the one-electron of reduction O2. In contrast to the apparent toxicity of this reaction, the biological consequences of O2⋅¯-mediated inactivation of the cytosolic counterpart of mitochondrial aconitase, commonly known as iron regulatory protein 1 (IRP1), are not clear. Apart from its ability to convert citrate to iso-citrate, IRP1 in its apo-form binds to iron-responsive elements in the untranslated regions of mRNAs coding for proteins involved in iron metabolism, to regulate their synthesis and thus control the cellular homeostasis of this metal. Here, we show that in superoxide dismutase 1 (SOD1) knock-out mice, lacking Cu,Zn-SOD, an enzyme that acts to reduce the concentration of O2⋅¯ mainly in cytosol, not only is aconitase activity of IRP1 inhibited but the level of IRP1 is also strongly decreased. Despite such an evident alteration in IRP1 status, SOD1-deficient mice display a normal iron metabolism phenotype. Our findings clearly show that under conditions of O2⋅¯-mediated oxidative stress, IRP1 is not essential for the maintenance of iron metabolism in mammals.
The experiment was performed on ISA broilers at big farm conditions. One day old chickens were randomly assigned to two poultry-houses with the capacity of 10
600 birds each. Chromium was provided in ...the form of chromium enriched yeast (1.0
g
Cr/kg yeast) given in doses of 0.2
mg
Cr/kg diet. No significant differences in growth rate and only a slight decrease of feed conversion ratio was found in broilers receiving chromium-yeast supplement. However, these birds had a lower mortality rate comparied with the rate observed in the controls. Moreover, dietary chromium led also to an improvement of carcass composition. Organic chromium supplementation increased the weight of pectoral muscles and meat of these broilers contained less amounts of fat and cholesterol. These effects were accompanied by an insignificant increase of chromium concentration in the pectoral muscles of birds fed chromium supplemented diets, from 40 to 52
μg/kg wet tissue.
The pig is born with limited iron supplies. If not supplemented, piglets dramatically loose their body iron stores during the first few days of postnatal life. The aim of this study was to ...investigate the influence of hepatic iron content on susceptibility of blood cells to oxidative stress. Four 1-day-old and three 7-days-old animals were used in this study. The alkaline version of the comet assay was used to measure DNA damage. As expected, iron body stores of non-supplemented animals decrease significantly during the first 4 days of life. However, no difference in background DNA damage was found between untreated lymphocytes from these two groups of animals, despite the difference in their hepatic iron content. Interestingly, DNA damage induced by H
2O
2 and X-radiation in lymphocytes taken from 1-day-old piglets was significantly higher than in those taken from 7-days-old animals. In contrast, NaOCl or
tert-butyl-hydroxide also induced significant amounts of DNA damage, but no differences between the two groups of piglets were found. Our data show that decreased hepatic iron content corresponds with decreased susceptibility of blood lymphocytes to oxidative stressors.
Abstract Biodegradable zinc oxide nanoparticles (ZnO NPs) are considered promising materials for future biomedical applications. To fulfil this potential, biodistribution and elimination patterns of ...ZnO NPs in the living organism need to be resolved. In order to investigate gastrointestinal absorption of ZnO NPs and their intra-organism distribution, water suspension of ZnO or fluorescent ZnO:Eu (Europium-doped zinc oxide) NPs (10 mg/ml; 0.3 ml/mouse) was alimentary-administered (IG: intra-gastric) to adult mice. Internal organs collected at key time-points after IG were evaluated by AAS for Zn concentration and analysed by cytometric techniques. We found that Zn-based NPs were readily absorbed and distributed (3 h post IG) in the nanoparticle form throughout the organism. Results suggest, that liver and kidneys were key organs responsible for NPs elimination, while accumulation was observed in the spleen and adipose tissues. We also showed that ZnO/ZnO:Eu NPs were able to cross majority of biological barriers in the organism (including blood–brain-barrier).
Summary
Thiamine deficiency resulted in inhibition of two main pathways supplying energy to the tissues: glycolysis and β‐oxidation. Glycolysis was found to be inhibited to 40% of initial value ...calculated on the basis of RBC trans‐membrane transport of glucose. Prolongation of experiment cause lowering of uptake of this sugar. In rats, energy production from fatty acids (FA) seems to be less sensitive to thiamine deficiency than glycolysis. After 30 days of feeding, utilization of FA in rats was depressed to the 61% of initial value. Thiamine deficiency suppressed insulin secretion, and the changes were statistically significant. Feeding of rats with thiamine restricted diet for 1 month caused the reduction of serum insulin by 14%. In the same animals, trans‐membrane glucose transport was reduced over two‐times, what might suggest a decreased efficiency of insulin action in such conditions. The kind and concentration of non‐digestible fructo‐oligosaccharides (FOS) did not affect significantly serum insulin concentration in animals fed thiamine restricted diet. Substitution of a part of wheat starch with FOS has only insignificant compensatory effect on the uptake of glucose. A partial amelioration of the β‐oxidation inhibition caused by feeding rats with thiamine deficient diet was observed in animals supplemented with FOS. However, this effect was statistically significant only in rats receiving diet containing 10% of inulin. The effect of supplemented FOS and their concentration on trans‐membrane glucose transport in RBC was statistically significant, when pulled supplementation groups were used for statistical evaluation.
Population genomics of Bronze Age Eurasia Allentoft, Morten E; Sikora, Martin; Sjögren, Karl-Göran ...
Nature (London),
06/2015, Letnik:
522, Številka:
7555
Journal Article
Recenzirano
Odprti dostop
The Bronze Age of Eurasia (around 3000-1000 BC) was a period of major cultural changes. However, there is debate about whether these changes resulted from the circulation of ideas or from human ...migrations, potentially also facilitating the spread of languages and certain phenotypic traits. We investigated this by using new, improved methods to sequence low-coverage genomes from 101 ancient humans from across Eurasia. We show that the Bronze Age was a highly dynamic period involving large-scale population migrations and replacements, responsible for shaping major parts of present-day demographic structure in both Europe and Asia. Our findings are consistent with the hypothesized spread of Indo-European languages during the Early Bronze Age. We also demonstrate that light skin pigmentation in Europeans was already present at high frequency in the Bronze Age, but not lactose tolerance, indicating a more recent onset of positive selection on lactose tolerance than previously thought.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Hereby the possible applications of oxide nanoparticles in the cancer diagnostics and therapy are presented. Cancer diseases are nowadays one of the most common causes of death in the ...highly-developed countries. Discussed will be the current clinical cancer detection methods with their shortcomings. The role of nanomedicine in cancer medicine and the potential applications of nanoparticles debated in the literature will be critically evaluated. In the second part, the most common methods for the nanoparticle synthesis will be discussed. Finally, the system for cancer detection based on the enhanced permeation-retention of multimodal high-k oxide nanoparticles doped with lanthanides will be proposed for both for themagnetic resonance imaging (non-gadolinium contrast agents) and for fluorescence guided biopsy and surgery.
PDF
