Marta Kepinska

Microarray analysis of metallothioneins in human diseases—A review

Metallothioneins (MTs), low molecular mass cysteine-rich proteins, which are able to bind up to 20 monovalent and up to 7 divalent heavy metal ions are widely studied due to their functions in detoxification of metals, scavenging free radicals and cells protection against the oxidative stress. It was found that the loss of the protective effects of MT leads to an escalation of pathogenic processes and carcinogenesis. The most extensive area is MTs expression for oncological applications, where the information about gene patterns is helpful for the identification biological function, resistance to drugs and creating the correct chemotherapy. In other medical applications the effect of oxidative stress to cell lines exposed to heavy metals and hydrogen peroxide is studied as well as influence of drugs and cytokines on MTs expression and MTs expression in the adipose tissue. The precise detection of low metallothionein concentrations and its isoforms is necessary to understand the connection between quantity and isoforms of MTs to size, localization and type of cancer. This information is necessary for well-timed therapy and increase the chance to survival. Microarray chips appear as good possibility for finding all information about expression of MTs genes and isoforms not only in cancer, but also in other diseases, especially diabetes, obesity, cardiovascular diseases, ageing, osteoporosis, psychiatric disorders and as the effects of toxic drugs and pollutants, which is discussed in this review.

The influence of oxidative stress induced by iron on telomere length.

Oxidative stress can be induced by increased concentrations of iron in the body and consequently can cause shortening of telomeres. Telomeres, called mitotic clocks, are non-coding fragments at the end of chromosomes. During the replication of genetic material they are shortened, playing the role of ageing biomarkers in eukaryotes. In human endothelial cells, oxidative stress causes a decrease in telomerase activity. Shortening of chromosomes in telomeric parts was found in patients with primary hemochromatosis and in patients taking supplements containing iron. Increased level of transferrin saturation is associated with the presence of shorter telomeres in the chromosomes of leukocytes. The relationship between iron status and telomere length is still not fully understood.

A Summary of New Findings on the Biological Effects of Selenium in Selected Animal Species—A Critical Review

Selenium is an essential trace element important for many physiological processes, especially for the functions of immune and reproductive systems, metabolism of thyroid hormones, as well as antioxidant defense. Selenium deficiency is usually manifested by an increased incidence of retention of placenta, metritis, mastitis, aborts, lowering fertility and increased susceptibility to infections. In calves, lambs and kids, the selenium deficiency demonstrates by WMD (white muscle disease), in foals and donkey foals, it is associated with incidence of WMD and yellow fat disease, and in pigs it causes VESD (vitamin E/selenium deficiency) syndrome. The prevention of these health disorders can be achieved by an adequate selenium supplementation to the diet. The review summarizes the survey of knowledge on selenium, its biological significance in the organism, the impact of its deficiency in mammalian livestock (comparison of ruminants vs. non-ruminants, herbivore vs. omnivore) and possibilities of its peroral administration. The databases employed were as follows: Web of Science, PubMed, MEDLINE and Google Scholar.

An insight into the complex roles of metallothioneins in malignant diseases with emphasis on (sub)isoforms/isoforms and epigenetics phenomena

ABSTRACT Metallothioneins (MTs) belong to a group of small cysteine‐rich proteins that are ubiquitous throughout all kingdoms. The main function of MTs is scavenging of free radicals and detoxification and homeostating of heavy metals. In humans, 16 genes localized on chromosome 16 have been identified to encode four MT isoforms labelled by numbers (MT‐1–MT‐4). MT‐2, MT‐3 and MT‐4 proteins are encoded by a single gene. MT‐1 comprises many (sub)isoforms. The known active MT‐1 genes are MT‐1A, ‐1B, ‐1E, ‐1F, ‐1G, ‐1H, ‐1M and ‐1X. The rest of the MT‐1 genes (MT‐1C, ‐1D, ‐1I, ‐1J and ‐1L) are pseudogenes. The expression and localization of individual MT (sub)isoforms and pseudogenes vary at intra‐cellular level and in individual tissues. Changes in MT expression are associated with the process of carcinogenesis of various types of human malignancies, or with a more aggressive phenotype and therapeutic resistance. Hence, MT (sub)isoform profiling status could be utilized for diagnostics and therapy of tumour diseases. This review aims on a comprehensive summary of methods for analysis of MTs at (sub)isoforms levels, their expression in single tumour diseases and strategies how this knowledge can be utilized in anticancer therapy.

Zinc-modified nanotransporter of doxorubicin for targeted prostate cancer delivery.

This work investigated the preparation of chitosan nanoparticles used as carriers for doxorubicin for targeted cancer delivery. Prepared nanocarriers were stabilized and functionalized via zinc ions incorporated into the chitosan nanoparticle backbone. We took the advantage of high expression of sarcosine in the prostate cancer cells. The prostate cancer targeting was mediated by the AntiSar antibodies decorated surface of the nanocage. Formation of the chitosan nanoparticles was determined using a ninhydrin assay and differential pulse voltammetry. Obtained results showed the strong effect of tripolyphosphine on the nanoparticle formation. The zinc ions affected strong chitosan backbone coiling both in inner and outer chitosan nanoparticle structure. Zinc electrochemical signal depended on the level of the complex formation and the potential shift from −960 to −950 mV. Formed complex is suitable for doxorubicin delivery. It was observed the 20% entrapment efficiency of doxorubicin and strong dependence of drug release after 120 min in the blood environment. The functionality of the designed nanotransporter was proven. The purposed determination showed linear dependence in the concentration range of Anti-sarcosine IgG labeled gold nanoparticles from 0 to 1000 µg/mL and the regression equation was found to be y = 3.8x − 66.7 and R2 = 0.99. Performed ELISA confirmed the ability of Anti-sarcosine IgG labeled chitosan nanoparticles with loaded doxorubicin to bind to the sarcosine molecule. Observed hemolytic activity of the nanotransporter was 40%. Inhibition activity of our proposed nanotransporter was evaluated to be 0% on the experimental model of S. cerevisiae. Anti-sarcosine IgG labeled chitosan nanoparticles, with loaded doxorubicin stabilized by Zn ions, are a perspective type of nanocarrier for targeted drug therapy managed by specific interaction with sarcosine and metallothionein for prostate cancer.

Transferrin Sialylation in Smoking and Non-Smoking Pregnant Women with Intrauterine Growth Restriction

Transferrin (Tf) is a glycosylated protein responsible for transporting iron. Various sialylation levels of Tf are observed during physiological and pathological processes. We studied if the changes in iron stores as well as tobacco smoke may have an impact on foetal development and in consequence lead to intrauterine growth restriction (IUGR). In the third trimester of pregnancy, lower levels of 4-sialoTf isoform and higher levels of 5-sialoTf were observed in the serum of non-smoking women with IUGR in comparison to the control group. On the day of labour, level of 2-sialoTf was significantly lower and level of 3-sialo was Tf higher in the serum of non-smoking women. Level of 4-sialo was found lower in the serum of smoking women with IUGR than in the control group. The observed changes may suggest a connection between iron stores, transport of iron to the foetus and foetal development.

Nano-selenium and its nanomedicine applications: a critical review

Traditional supplements of selenium generally have a low degree of absorption and increased toxicity. Therefore, it is imperative to develop innovative systems as transporters of selenium compounds, which would raise the bioavailability of this element and allow its controlled release in the organism. Nanoscale selenium has attracted a great interest as a food additive especially in individuals with selenium deficiency, but also as a therapeutic agent without significant side effects in medicine. This review is focused on the incorporation of nanotechnological applications, in particular exploring the possibilities of a more effective way of administration, especially in selenium-deficient organisms. In addition, this review summarizes the survey of knowledge on selenium nanoparticles, their biological effects in the organism, advantages, absorption mechanisms, and nanotechnological applications for peroral administration.

The Influence of Tobacco Smoke on Protein and Metal Levels in the Serum of Women during Pregnancy

Background Tobacco smoking by pregnant women has a negative effect on fetal development and increases pregnancy risk by changing the oxidative balance and microelements level. Smoking affects the concentration, structure and function of proteins, potentially leading to various negative effects on pregnancy outcomes. Methodology/Principal Findings The influence of tobacco smoke on key protein fractions in smoking and non-smoking healthy pregnant women was determined by capillary electrophoresis (CE). Concentrations of the proteins α1-antitrypsin, α1-acid glycoprotein, α2-macroglobulin and transferrin were determined by ELISA tests. Total protein concentration was measured by the Biuret method. Smoking status was established by cotinine levels. Cadmium (Cd) and Zinc (Zn) concentrations were determined by flame atomic absorption spectrometry and the Zn/Cd ratio was calculated based on these numbers. Smoking women had a 3.7 times higher level of Cd than non-smoking women. Zn levels decreased during pregnancy for all women. The Zn/Cd ratio was three times lower in smoking women. The differences between the changes in the protein profile for smoking and non-smoking women were noted. Regarding proteins, α1-antitrypsin and α2-macroglobulin levels were lower in the non-smoking group than in the smoking group and correlated with Cd levels (r = -0.968, p = 0.032 for non-smokers; r = −0.835, p = 0.019 for smokers). Zn/Cd ratios correlated negatively with α1-, α2- and β-globulins. Conclusions/Significance Exposure to tobacco smoke increases the concentration of Cd in the blood of pregnant women and may lead to an elevated risk of pregnancy disorders. During pregnancy alter concentrations of some proteins. The correlation of Cd with proteins suggests that it is one of the causes of protein aberrations.

Influence of tobacco smoking on transferrin sialylation during pregnancy in smoking and non-smoking women with iron deficiency.

OBJECTIVES Tobacco smoking influence on proteins is leading to despaired foetal nourishment. Transferrin, is an essential metal-binding protein responsible for iron transport and proper foetal development. This study examines influence of tobacco smoking on transferrin sialic acid residues and its connection to foetal nourishment at women with iron deficiency. METHODS The study involved 190 samples from pregnant women in 1st, 2nd and 3rd trimester. Women were divided in terms of tobacco smoking and iron deficiency. RESULTS During pregnancy, the levels of 2-, 5- and 6-sialo transferrin were increasing while 3- and 4-sialo transferrin were decreasing in all groups. Transferrin isoforms showed positive correlation with lowered iron stores in the blood of non-smoking women. CONCLUSION Tobacco smoking has an influence on number of sialic acids residues in the transferrin and seems to change conversion of Tf isoforms, and this may disturb iron transport and in consequence influence on foetal development and nourishment.

Inhibition of copper-zinc superoxide dismutase activity by selected environmental xenobiotics

The function of Cu,Zn-SOD is to dismutate superoxide into hydrogen peroxide and oxygen. This task is fulfilled due to structural nuances of the enzyme. Many environmental xenobiotics have been proved to inhibit Cu,Zn-SOD. Those compounds could be found not only in industrial sewage, cigarettes and various chemical agents - some of them are used as drugs, drug production substrates or are the product of drug biotransformation. Cu,Zn-SOD exposition to these compounds leads to inhibition due to: copper ion chelation, unfolding the structure of the enzyme, affecting residues vital for activity maintenance. This review covers a selection of Cu,Zn-SOD inhibitors, referring to in vivo and in vitro study.