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Guranowski A.,University of Life Sciences in Poznan | Wojdyla A.M.,University of Life Sciences in Poznan | Zimny J.,University of Life Sciences in Poznan | Wypijewska A.,Institute of Experimental Physics | And 4 more authors.
FEBS Letters | Year: 2010

Histidine triad (HIT)-family proteins interact with different mono- and dinucleotides and catalyze their hydrolysis. During a study of the substrate specificity of seven HIT-family proteins, we have shown that each can act as a sulfohydrolase, catalyzing the liberation of AMP from adenosine 5′-phosphosulfate (APS or SO4-pA). However, in the presence of orthophosphate, Arabidopsis thaliana Hint4 and Caenorhabditis elegans DcpS also behaved as APS phosphorylases, forming ADP. Low pH promoted the phosphorolytic and high pH the hydrolytic activities. These proteins, and in particular Hint4, also catalyzed hydrolysis or phosphorolysis of some other adenylyl-derivatives but at lower rates than those for APS cleavage. A mechanism for these activities is proposed and the possible role of some HIT-proteins in APS metabolism is discussed. © 2009 Federation of European Biochemical Societies. Source

Gawinkowski S.,Polish Academy of Sciences | Walewski L.,The Interdisciplinary Center | Vdovin A.,University of Regensburg | Slenczka A.,University of Regensburg | And 5 more authors.
Physical Chemistry Chemical Physics | Year: 2012

Combined use of IR, Raman, neutron scattering and fluorescence measurements for porphycene isolated in helium nanodroplets, supersonic jet and cryogenic matrices, as well as for solid and liquid solutions, resulted in the assignments of almost all of 108 fundamental vibrations. The puzzling feature of porphycene is the apparent lack of the N-H stretching band in the IR spectrum, predicted to be the strongest of all bands by standard harmonic calculations. Theoretical modeling of the IR spectra, based on ab initio molecular dynamics simulations, reveals that the N-H stretching mode should appear as an extremely broad band in the 2250-3000 cm -1 region. Coupling of the N-H stretching vibration to other modes is discussed in the context of multidimensional character of intramolecular double hydrogen transfer in porphycene. The analysis can be generalized to other strongly hydrogen-bonded systems. © the Owner Societies 2012. Source

Boltze J.,Fraunhofer Institute for Cell Therapy and Immunology | Lukomska B.,Mossakowski Medical Research Center | Jolkkonen J.,University of Eastern Finland
Journal of Cerebral Blood Flow and Metabolism | Year: 2014

Experimental stroke treatment by mesenchymal stem cell (MSC) populations is an attractive paradigm in stroke research. There are many studies describing improved functional outcomes after MSC delivery in stroke, but the mechanisms through which the transferred cells exert these effects are less well understood. Moreover, commonly applied functional tests may not be suitable for discriminating real functional recovery from compensation, which is a frequently encountered phenomenon in rodents. This commentary highlights some of the potential risks for the translational process associated with these tests and proposes some alternative test arrays which may achieve more specific functional phenotyping. © 2014 ISCBFM. Source

Koronkiewicz M.,Polish National Medicines Institute | Chilmonczyk Z.,Polish National Medicines Institute | Kazimierczuk Z.,Mossakowski Medical Research Center
Medicinal Chemistry Research | Year: 2012

A series of new pentabromobenzylisothioureas [ZKK-1-ZKK-5; (ZKKs)] carrying additional substituents on nitrogen atoms has been synthesized. The ZKKs were found to induce apoptosis in HL-60 (human promyleocytic leukemia) and K-562 (human chronic erythromyeloblastoid leukemia) cell lines in a concentration-dependent manner at low micromolar concentrations. ZKK-3 [(N,N'- dimethyl-S-2,3,4,5,6-pentabromobenzyl)isothiouronium bromide] showed the highest proapoptotic activity in HL-60 cells, whereas ZKK-2 [N-methyl-S-(2,3,4,5,6- pentabromobenzyl)isothiouronium bromide] was most effective in this respect in K-562 cells. During the ZKKsinduced apoptosis, an 85 kDa fragment of cleaved PARP (caspase-3 and caspase-7 substrate) was detected in both cell lines tested. The studied compounds also decreased mitochondrial transmembrane potential in both these cell lines and caused the cells to accumulate in G 1 and at the G 1/S border of the cell cycle in a concentration-dependent manner. These results show promise for their study as new compounds in the treatment of leukemia, after an appropriate preclinical toxicity profile. © Springer Science+Business Media, LLC 2011. Source

Dobrzyn P.,Nencki Institute of Experimental Biology | Pyrkowska A.,Nencki Institute of Experimental Biology | Jazurek M.,Nencki Institute of Experimental Biology | Szymanski K.,Nencki Institute of Experimental Biology | And 2 more authors.
Journal of Applied Physiology | Year: 2010

Stearoyl-CoA desaturase (SCD), a rate-limiting enzyme in the biosynthesis of monounsat-urated fatty acids, has recently been shown to be a critical control point in regulation of liver and skeletal muscle metabolism. Herein, we demonstrate that endurance training significantly increases both SCD1 mRNA and protein levels in the soleus muscle, whereas it does not affect SCD1 expression in the EDL muscle and liver. Desaturation index (18:1Δ9/18:0 ratio), an indirect indicator of SCD1 activity, was also significantly higher (3.6-fold) in soleus of trained rats compared with untrained animals. Consistent with greater SCD1 expression/activity, the contents of free fatty acids, diacylglycerol, and triglyceride were elevated in soleus of trained rats. However, training did not affect lipid concentration in EDL and liver. Additionally, endurance training activated the AMP-activated protein kinase pathway as well as increased peroxisome proliferator-activated receptor (PPAR)-§ and PPARα gene expression and activity in soleus and liver. Increased lipid accumulation in soleus was coupled with elevated protein levels of fatty acid synthase, mRNA levels of diacylglycerol acyltransferase and glycerol-3-phosphate transferase, as well as increased levels of proteins involved in fatty acid transport (fatty acid translocase/CD36, fatty acid transport protein 1). Interestingly, sterol regulatory element-binding protein (SREBP)-1c expression and SREBP-1 protein levels were not affected by exercise training. Together, the obtained data suggest that SCD1 upregulation plays an important role in adaptation of oxidative muscle to endurance training. Copyright © 2010 the American Physiological Society. Source

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