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Objective: Diabetes mellitus is one of the most crippling diseases that man has seen and its prevalence has risen dramatically over the past two decades. Currently there are over the 150 million diabetics worldwide and this number is likely to increase to 300 million or more by the year 2025. Diabetes mellitus increases the risk of many disorders including cardiovascular diseases. Understanding the molecular properties of diabetic progression is a big challenge in systems-biology era. Methods: The 3-aminobenzanthrone derivative ABM, developed at the Daugavpils University, Latvia, has been previously shown as a potential biomarker for determination of the immune state of patients with different pathologies. The aim of this study was to determine the several aspects of membrane alterations in the group of Chernobyl clean-up workers with diabetes mellitus in relation with its common group without diabetes mellitus and humans having no professional contact with radioactivity. The following parameters were examined: (1) the spectral characteristics of ABM in cell suspension (e.g. anisotropy index); (2) quantitative parameters of protein/lipid interaction in liposomes prepared from phosphatidylcholine and its mixtures with cardiolipin and cholesterol. Results: Screening of the individuals with diabetes mellitus 25-26 years after the work in Chernobyl revealed two groups of patients differing in structural and functional membrane properties, first of all on the lipid/protein interrelations and conformations of membrane proteins. The revealed structural modifications of membranes are dependent on radiation-induced factors. Concomitant diseases (diabetes mellitus, cardiovascular diseases) reinforce radiation induced effects. Conclusion: ABM is a sensitive probe of membrane architecture alterations, and can be used to elucidate the changes in membrane systems. Significant differences in membrane dynamics exist between control (donors), and diabetics and non-diabetics groups of Chernobyl clean-up workers [J Exp Integr Med 2012; 2(4): 357-363

Plants as sessile organisms are exposed to persistently changing stress factors. Heat stress adversely affects plant growth and development and induces oxidative stress in plants. To understand the effect of high-temperature stress on plant growth and development, it is necessary to study the physiology and morphology of whole plants and their organs. The oxidative stress level was assessed by increased production of lipid peroxidation (LP) products, such as malondialdehyde (MDA) and conjugated dienes (CD), and cellular membrane permeability, as evaluated by electrolyte leakage (EL) in different wheat (Triticum aestivum cv. Harmonija) organs after 24-hour high-temperature (42 °C) treatment. Measurements of relative water content (RWC) in leaf tissues were used to assess water deficits in plants. High-temperature treatment had no effects on RWC in the root, but reduced RWC in the coleoptile at all investigated stages of seedling development and in the first leaf (p ≤ 0.01) at the late stages of development. A 24-h hightemperature exposure completely inhibited the growth of the first leaf and root (p ≤ 0.001). LP significantly increased in the coleoptiles of wheat seedlings due to high temperature, but in contrast LP in the root was similar to control at all investigated stages of development. A significant increase of LP products (p ≤ 0.01) was observed in the first leaf at the late stages of wheat seedling development. Such elevated level of LP led to increase of cellular membrane permeability. 24-h high temperature results in the desiccation of the first leaf and coleoptile. Obviously the root of wheat seedlings is less sensitive to heat stress than the first leaf and coleoptiles. The study revealed that specific effects of high temperature on the root result in increase of electrolyte leakage, but high temperature hardly affects lipid peroxidation processes.

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Flooding occurs in many wheat-growing regions around the world. During flooding, the gas exchange between soil and air decreases and root hypoxia or anoxia is the major cause of plant growth reduction under this stress. The hypoxia stress triggers stimulate the formation of reactive oxygen species (ROS) and induce oxidative stress in plants. The wheat is one of the most important crops in Latvia and in the world. Although wheat is one of the most intolerant crops to soil flooding. To elucidate the mechanisms involved in soil flooding and the tolerance of three Latvian commercial winter wheat (Triticum aestivum L.) cultivars: ‘Fredis’, ‘Reinis’, ‘Brencis’ and the flooding induced changes in electrolyte leakage, MDA production, and carotenoid production evaluated. The results indicate, that content of MDA, which reflect the level of membrane lipid peroxidation, differ, but no significant decrease of MDA concentration in cultivar ‘Brencis’ caused by increased activity of the antioxidant system. The differences in total carotenoids content in investigated wheat cultivars under simulating natural flooding founded. The most active accumulation of total carotenoids observed in the cultivar ‘Reinis’. The results demonstrate increased electrolyte leakage in cell membranes of the first leaves in all investigated wheat cultivars compared to control. Under flooding, the first leaf of wheat influenced by lower water temperature compared to the first leaf of the control group and that decrease the membrane fluidity, which possibly leads to decreased of membrane permeability. This preliminary data shows that one-week flooding influences to the cell membranes of some Latvian winter wheat cultivars, this influence differs, but cultivar ‘Brencis’ was more tolerant of the flooding.