Aleksandar Bulog

Metallothioneins and heat shock proteins 70 in marine mussels as sensors of environmental pollution in Northern Adriatic Sea

In an attempt to assess the intensity of environmental pollution in industrial zones of Kvarnerian Bay in Northern Adriatic Sea and the reactivity of Mytilus galloprovincialis to these changes, in this study we estimated the concentration of heavy metals at four locations in both sea-sediment and in the mussels. Further we tried to correlate these changes with seasonal variations in environmental temperature, pH and salinity, as well as with the expression of metallothioneins (MTs) and heat shock proteins (HSPs) in the digestive tract of the mussels. Sampling in vivo was performed monthly, during the year 2008, while under the laboratory conditions the reactivity of acclimated mussels were tested to increasing concentrations of CdCl(2) and to thermal stress. The data have shown that the induction of MTs and HSP isoforms of the 70-kDa size class were highly affected by model agents treatment including contamination of sea-sediment by Pb, Hg and Cd, implying that these stress proteins might be power biomarkers of marine pollution.

Evaluation of Urinary Btex, Nicotine, and Cotinine as Biomarkers of Airborne Pollutants in Nonsmokers and Smokers.

Benzene, toluene, ethylbenzene, and isomeric xylenes (BTEX) are by-products of tobacco smoke and traffic emissions. The aim of this study was to determine the contribution of cigarette smoking to urinary levels of BTEX present in humans. Nicotine and cotinine, biomarkers of exposure to tobacco smoke, as well as BTEX, were measured in urine of smokers (n = 70) and nonsmokers (n = 65) using headspace solid-phase microextraction (HS-SPME) followed by gas chromatography–mass spectrometry (GC-MS). In smokers, a significant correlation was found between urinary BTEX levels and nicotine and cotinine. In addition, significant regression models with nicotine and cotinine as predictors showed that BTEX in smokers’ urine was predominantly derived from exposure to tobacco smoke. In nonsmokers a weak correlation between BTEX and nicotine and cotinine was found in urine. Further, there was a lack of significant contribution of BTEX to urinary nicotine and cotinine concentrations in nonsmokers. Thus, it was presumed that vehicle exhaust was the main source of exposure to BTEX in nonsmokers.

Crosstalk Between Enzyme Matrix Metalloproteinases 2 and 9 and Regulatory T Cell Immunity in the Global Burden of Atherosclerosis.

Changes in immune and inflammatory responses may play a crucial role in the development and progression of atherosclerosis, as an autoimmune, chronic and progressive inflammatory disease. Immunological activity and vascular inflammation during atherosclerosis can be modulated by autoimmune responses against self‐antigens, according to changeable risk factors (cholesterol, oxidized low‐density lipoprotein (ox‐LDL) in the vascular wall, fatty acids, etc.), and accompanied by accumulation of leucocytes and proinflammatory cytokines, which stimulate the transcription of matrix metalloproteinases (MMPs), whose concentration are increased in foam cell‐rich regions. Regulatory T cells (Tregs) represent a unique subpopulation of T cells specialized in the regulation of immune response and in the suppression of proatherogenic T cells. The aim of our study was to examine the interactions between the concentration of enzyme matrix metalloproteinases 2 and 9 (MMP‐2 and 9) in urine and the percentage of Tregs in peripheral blood of two groups of patients: with carotid artery stenosis (CAS), undergoing surgery and with mild atherosclerosis (A) from general practice. The method of enzyme immunoassay (ELISA) was used to determine enzyme MMP expression, and Tregs was examined by flow cytometric analysis. Our data have showed a large increase in the enzyme MMP‐2 and 9 in the urine of CAS and A patients in comparison with healthy controls and indicated this method as an easy marker for the monitoring of the development of atherosclerosis. Simultaneously, the diminished number of Tregs in the same patients pointed the importance of these regulatory mechanisms in the etiopathogenesis of atherosclerosis and possible Tregs‐mediated therapy.

70-kDa heat shock cognate protein expression as a putative biomarker of heavy-metal burden in Mytilus galloprovincialis

BackgroundHeavy metals naturally occur in the marine environment and ecosystems. Due to anthropogenic influence they became common waters and coastal regions pollutants in particular where their concentrations remain hazardously high. We therefore tested a protocol for combined analysis of 6 heavy metal (Pb, Cd, Cr, Zn, Fe and Hg) concentrations in mussels Mytilus galloprovincialis collected from a coastal industrial zone (shipyard locality) and mariculture facilities in combination with expression analysis of multi xenobiotic resistance related genes and stress-related gene (HSC-70).FindingsIn this paper we tested a protocol for heavy-metal levels assessment by use of a highly sensitive analytical method, ICP-OES, combined with expression analysis of multi xenobiotic resistance related genes, including the stress-related gene encoding 70-kDa heat shock cognate protein on mussels (Mytillus Galloprovincialis). Mussels from the shipyard locality had higher heavy metal concentrations, except Fe. Higher metal concentrations did not influence expression of multi xenobiotic resistance related genes with exception of stress-related gene (HSC-70) encoding 70-kDa heat shock cognate protein.ConclusionsOur results indicate that mussels sampled in the industrial area have increased metal concentrations in comparison with the aquaculture locality, that are accompanied by increased transcript levels of HSC-70.