Investigation of trace element concentration in diabetic rat's tissues

Diabetes is one of the most frequent diseases in developing countries and thus there is a significant interest in diabetes related studies. It was found that vanadium compounds have glucose-lowering properties in diabetes and therefore it is very important to estimate the vanadium dose in diabetes treatment. On the other hand, the proper estimation of vanadium concentration is important due to side effects that occur in vanadium supplementation. In this study the influence of V(IV) and V(V) compounds with different ligands on the concentration of K, Ca, Mn, Fe, Cu, and Zn in selected rat’s tissues was investigated by means of proton induced X-ray emission technique. As a result of the measurements it was found that the concentration of vanadium depends on the organ. The highest value was determined in spleen while the lowest in pancreas. It was also found that the concentration of other elements depends on the presence of vanadium and its concentration. The most meaningful influence of vanadium presence was on iron concentration in spleen, on copper and zinc in kidney, and on manganese in pancreas

Biological applications of synchrotron radiation infrared spectromicroscopy.

Extremely brilliant infrared (IR) beams provided by synchrotron radiation sources are now routinely used in many facilities with available commercial spectrometers coupled to IR microscopes. Using these intense non-thermal sources, a brilliance two or three order of magnitude higher than a conventional source is achievable through small pinholes (<10 mu m) with a high signal to-noise ratio. IR spectroscopy is a powerful technique to investigate biological systems and offers many new imaging opportunities. The field of infrared biological imaging covers a wide range of fundamental issues and applied researches such as cell imaging or tissue imaging. Molecular maps with a spatial resolution down to the diffraction limit may be now obtained with a synchrotron radiation IR source also on thick samples. Moreover, changes of the protein structure are detectable in an IR spectrum and cellular molecular markers can be identified and used to recognize a pathological status of a tissue. Molecular structure and functions are strongly correlated and this aspect is particularly relevant for imaging. We will show that the brilliance of synchrotron radiation IR sources may enhance the sensitivity of a molecular signal obtained from small biosamples, e.g., a single cell, containing extremely small amounts of organic matter. We will also show that SR IR sources allow to study chemical composition and to identify the distribution of organic molecules in cells at submicron resolution is possible with a high signal-to-noise ratio. Moreover, the recent availability of two-dimensional IR detectors promises to push forward imaging capabilities in the time domain. Indeed, with a high current synchrotron radiation facility and a Focal Plane Array the chemical imaging of individual cells can be obtained in a few minutes. Within this framework important results are expected in the next years using synchrotron radiation and Free Electron Laser (FEL) sources for spectro-microscopy and spectral-imaging, alone or in combination with Scanning Near-field Optical Microscopy methods to study the molecular composition and dynamic changes in samples of biomedical interest at micrometric and submicrometric scales, respectively. (c) 2012 Elsevier Inc. All rights reserved

X‐Ray Spectroscopy on Biological Systems

In the field of biological studies, next to the standard methods, new tools are offered by contemporary physics. X‐ray spectroscopic techniques enable probing electronic structure of occupied and unoccupied states of studied atom and distinguish the oxidation state, local geometry, and ligand type of elements that occur in biological material. Direct analysis using X‐ray spectroscopy avoids many chemical preparation steps that might modify biological samples. The information obtained gives us insight into important biochemical processes all under physiological conditions. In this chapter we focus our attention to the application of X‐ray spectroscopy to the study of biological samples, with special emphasis on mechanisms revealing interaction between DNA and different cytotoxic agents and in the determination of changes in oxidation state of different elements in pathologically altered human cells and tissue

Effects of vanadium complexes supplementation on V, Cu, Mn, K, Fe, Zn, and Ca concentration in STZ diabetic rats pancreas

The objective of the study was to assess the effects of Na[V V O(O 2 ) 2 (2,2í-bpy)] ◊ 8 H 2 O (complex 1), Na[V V O(O 2 ) 2 (1,10í-phen)] ◊ 5 H 2 O (complex 2 ), Na[V V O(O 2 ) 2 (4,4í-Me-2,2í-bpy)] ◊ 8 H 2 O (complex 3 ), [ V IV O(SO 4 )(1,10í-phen)] ◊ 2 H 2 O, (complex 4 ), [ V IV O(SO 4 )(2,2í-bpy)] ◊ H 2 O (complex 5 ), where: 2,2í-bpy = 2,2í-bipyridine, 1,10í-phen = 1,10í-phenanthroline, 4,4í-Me-2,2í-bpy = 4,4í-dimethyl-2,2í-bipyridine and a small insulin injection on V, Cu, Mn, K, Fe, Zn, and Ca concentration in the STZ (streptozotocin) diabetic rats pancreas during a 5-week treatment with the tested complexes. In all groups of animals metal concentration in the pancreas was investigated by means of Proton Induced X-ray Emission (PIXE) method. Maximum con- centration of vanadium was observed in the pancreas for complex 5 (1.69 ± 0.09 mg/kg dry weight), lower for complex 3 (1.51 ± 0.10 mg/kg dry weight), and the lowest for complex 1 (1.21 ± 0.27 mg/kg dry weight) sup- plementation. The influence of vanadium administration on other metalsí concentration in the ratsí pancreas was also investigated. All vanadium-tested complexes showed an increase of zinc concentration in the exam- ined pancreas in comparison to the diabetic animals not treated with vanadium. The results were the highest for complex 1 and the lowest for complex 5. The concentration of Fe, Cu, Mn, K and Ca in the pancreas is not evi- dently influenced by administration of the vanadium complexe

First approach to studies of sulphur electron DOS in prostate cancer cell lines and tissues studied by XANES

Abstract Urological cancers comprise approximately one-third of all cancers diagnosed in men worldwide and out of these, prostate cancer is the most common one ( WHO World Cancer Report, 2008 ). Several risk factors such as age, hormone levels, environmental conditions and family history are suspected to play a role in the onset of this disease of otherwise obscure aetiology. It is therefore the medical need that drives multidisciplinary research in this field, carried out by means of various experimental and theoretical techniques. Out of many relevant factors, it is believed that sulphur can take an important part in cancer transformations. We have investigated the prostate cancer cell lines and tissues, along with selected organic and inorganic compounds used as references, by the X-ray absorption fine structure spectroscopy near the sulphur edge energy region. Particularly, the comparison of the experimental results collected during XANES measurements and theoretical calculations of electron density of states with use of the FEFF8 code and LAPW (linearised augmented plane-wave) method has been performed and in this work the first results of our studies are presented

Surface study of selected biomaterials using vibrational spectroscopy

Vibrational spectroscopy has been extensively used for in vitro and in vivo investigations of degradation mechanism and kinetics of different biomedical materials as well as it has been used to characterize the crystalline and amorphous domains in bio-mineralization process. Infrared and Raman spectroscopy methods are valuable tools in the biomaterials engineering allowing to study processes occurring during their preparation. In vitro tests, where the materials are immersed in simulated body fluids and/or artificial saliva, were used to evaluate the biocompatibility of biomaterials. This kind of tests are a wide range of repeatable and reproducible methods, which are regulated by international standards for commercial use and scientific development of new materials and products. The aim of this work was to examine phase composition of materials applied in dentistry. The bioactivity of such biomaterials was studied by immersing the samples in synthetic body fluid and artificial saliva. The changes were determined by the Fourier transform infrared and Raman microspectroscopy as well as scanning electron microscopy. It was found that results obtained by vibrational spectroscopy show the differences between the studied samples. Chemical reactions occurring during incubation of cements in artificial saliva as well as in synthetic body fluid result in formation of phosphates which deposit on the cement surface

Influence of vanadium-organic ligands treatment on selected metal levels in kidneys of STZ rats

The objective of the study was to investigate the effects of five organic vanadium complexes supplement and a small dose of insulin injection on V, Fe, Cu, Zn, Mn, Ca, and K level in the streptozotocin diabetic rat’s kidney during a 5-week treatment with the tested complexes. In all groups of animals, metal level in the lyophilized kidney organs was investigated by means of the proton induced X-ray emission method. Tissue vanadium level was naturally higher in vanadium-treated rats. The maximum level of vanadium was observed in the kidney (x(mean) = 16.6 μg/g). The influence of vanadium administration on other metal level in rat’s tissue was also investigated. Spectacular influence of vanadium action was observed on copper and zinc level in examined tissue

Stearoyl-CoA desaturase 1 activity determines the maintenance of DNMT1-mediated DNA methylation patterns in pancreatic β\beta-Cells

Metabolic stress, such as lipotoxicity, affects the DNA methylation profile in pancreatic &beta;-cells and thus contributes to &beta;-cell failure and the progression of type 2 diabetes (T2D). Stearoyl-CoA desaturase 1 (SCD1) is a rate-limiting enzyme that is involved in monounsaturated fatty acid synthesis, which protects pancreatic &beta;-cells against lipotoxicity. The present study found that SCD1 is also required for the establishment and maintenance of DNA methylation patterns in &beta;-cells. We showed that SCD1 inhibition/deficiency caused DNA hypomethylation and changed the methyl group distribution within chromosomes in &beta;-cells. Lower levels of DNA methylation in SCD1-deficient &beta;-cells were followed by lower levels of DNA methyltransferase 1 (DNMT1). We also found that the downregulation of SCD1 in pancreatic &beta;-cells led to the activation of adenosine monophosphate-activated protein kinase (AMPK) and an increase in the activity of the NAD-dependent deacetylase sirtuin-1 (SIRT1). Furthermore, the physical association between DNMT1 and SIRT1 stimulated the deacetylation of DNMT1 under conditions of SCD1 inhibition/downregulation, suggesting a mechanism by which SCD1 exerts control over DNMT1. We also found that SCD1-deficient &beta;-cells that were treated with compound c, an inhibitor of AMPK, were characterized by higher levels of both global DNA methylation and DNMT1 protein expression compared with untreated cells. Therefore, we found that activation of the AMPK/SIRT1 signaling pathway mediates the effect of SCD1 inhibition/deficiency on DNA methylation status in pancreatic &beta;-cells. Altogether, these findings suggest that SCD1 is a gatekeeper that protects &beta;-cells against the lipid-derived loss of DNA methylation and provide mechanistic insights into the mechanism by which SCD1 regulates DNA methylation patterns in &beta;-cells and T2D-relevant tissues