Volume 6, Issue 1

It is documented that deficient fucosylation may play an important role in the pathogenesis of cancer. Since the supplementation of L-fucose could restore fucosylation in both in vitro and in vivo conditions, our intent was to examine the effect of intraperitoneal administration of L-fucose and L-rhamnose (a similar deoxysaccharide) on tumour growth, mitotic activity and metastatic setting of a solid form of Ehrlich carcinoma as well as on the survival rate of tumour bearing mice. Both L-fucose and L-rhamnose exerted a significant suppressive effect on tumour growth (P<0.05). After 10 days of therapy, the greatest inhibition of tumour growth expressed as a percentage of controls was observed in L-rhamnose at a dose of 3 g/kg/day (by 62%) and L-fucose at a dose of 5 g/kg/day (by 47%). Moreover, the mitotic index decreased with increasing doses of L-fucose and L-rhamnose. Prolonged survival of tumour bearing mice was observed after 14 consecutive days of daily administering L-rhamnose. Its optimal dose was estimated to be 3.64 g/kg/day. L-Fucose, however, displayed only a slight effect on the survival of the mice. Our results suggest that L-fucose and especially L-rhamnose have anticancer potential. This study is the first to demonstrate the tumour-inhibitory effect of L-rhamnose.

This study examined the presence and cellular localization of three types of opioid receptors (MOR, DOR and KOR) in five human cancer cell lines: MCF-7, MDA-MB-231, HT-29, MGH-U1 and SH-SY5Y. Expression levels of opioid receptors were measured quantitatively using real-time PCR, and the localizations of the receptors in the cells were determined by immunocytochemistry. All three types of opioid receptors were present in each of the five cell lines examined. However, three of the cell lines (MCF-7, HT-29 and SH-SY5Y) showed significantly higher levels of MOR mRNA and protein than the other two types of receptors (DOR and KOR). Immunocytochemistry revealed that MOR, DOR and KOR receptors were predominantly present on the surface of cell membranes, although these receptors were also occasionally present in the cell cytoplasm.

Tacrine, a well-known acetylcholinesterase inhibitor, applied in concentrations higher than 2×10−5 mol/l promoted Ca2+-independent relaxation of rat gastric smooth muscles in experiments in vitro. The relaxation was not cholinergic and was a result of influence of tacrine over intracellular signaling pathways regulating smooth muscle contraction/relaxation. The nature of this untypical muscle relaxation was studied by using smooth muscle strips isolated from rat stomach. Their bioelectrical and mechanical responses were recorded after treatment with tacrine and different activators or blockers of intracellular pathways involved in muscle contractility. Following the activation of adenylate cyclase with 1×10−6 mol/l forskolin and increase in the concentration of cyclic adenosine monophosphate (cAMP) after application of 4×10−5 mol/l SQ22536, a significant decrease in the muscle relaxation was observed. Theophylline (2×10−4 mol/l), a phosphodiesterase inhibitor, had no effect on the amplitude of tacrine-induced relaxation. The latter was also reduced by inhibition of protein kinase A (PKA) with 5×10−6 mol/l KT5720. These findings support the assumption that tacrine promoted smooth muscle relaxation through PKA-induced phosphorylation and inhibition of myosin light chain kinase activity. The reduction of spike-linked Ca2+ influx provoked by tacrine was probably a secondary contributing process, associated with an influence of increased cAMP level on Ca2+ channels.

Epidemiological studies show that the risk for cardiovascular diseases increases with increasing levels of free-copper in plasma. It is known that intact ceruloplasmin (CP), the major protein transporter of copper in human plasma, oxidizes low density lipoproteins (LDL) in vitro. Our aim was to study the interaction between LDL and CP in vitro and in vivo, in an animal model of diet-induced atherosclerosis. In order to visualize the pathway of LDL into the arterial wall, human native LDL was labeled with fluorescent DiI and injected into male, Golden Syrian hyperlipemic hamsters. In vitro results demonstrated that slightly degraded CP has a significant oxidation potential against LDL at neutral pH. In vivo, after 24 hours circulation, LDL-DiI was taken up by the enlarged intima and fatty streaks of the arterial wall. Immunohistochemical localization of oxidized LDL and CP revealed their presence in the same areas of the arteries that take up LDL-DiI. Co-localization of LDL and CP in the enlarged intima of pro-atherosclerotic areas might explain the possible copper-induced oxidation process that might occur after native LDL is taken-up from the blood, transcytosed through the endothelium and accumulated in focalized deposits.

Reducing postprandial oxidative stress (OxS), decreasing postprandial blood triglyceride level (TG) and improving lipoprotein status is likely to have a preventive impact on the development of cardiovascular disease (CVD). Previously we have shown that the antioxidant probiotic Lactobacillus fermentum ME-3 (DSM14241) is characterized by antiatherogenic effects. This randomized double-blind placebo-controlled study evaluated the influence of kefir enriched with an antioxidative probiotic L. fermentum ME-3 (LfKef) on postprandial OxS, blood TG response and lipoprotein status. 100 clinically healthy subjects were recruited into the study. Blood parameters of postprandial OxS, TG and lipoprotein status were determined by oxidized LDL, baseline diene conjugation in LDL (BDC-LDL), oxidized LDL complex with beta-2 glycoprotein (Beta2-GPI-oxLDL), paraoxonase (PON) activity, LDL-Chol, HDL-Chol and TG. To evaluate general body postprandial OxS-load we measured 8-isoprostanes (8-EPI) in the urine. Consumption of LfKef significantly reduced the postprandial level of oxidized LDL, BDC-LDL, Beta2-GPI-oxLDL, urinary 8-isoprostanes and postprandial TG and caused a significant increase in HDL-Chol and PON activity. This is the first evidence that kefir enriched with an antioxidant probiotic may have a positive effect on both postprandial OxS and TG response as well as on lipoprotein status.

Administration of estradiol or calcium, or combined, represents the classical therapeutic approach in the treatment of some menopausal symptoms. We have studied the effects of estradiol dipropionate (EDP) and calcium glucoheptonate (Ca) on morphological and hormonal features of the adrenal gland in 14-month-old female Wistar rats. The animals were treated with EDP (0.625 mg/kg b.w.) or Ca (11.4 mg/kg b.w.) daily for two weeks, with control rats receiving vehicle alone by the same schedule. The cell volumes in the zona glomerulosa (ZG) and zona fasciculata (ZF) were 11.2% and 5.5% greater (P<0.05) and in the zona reticularis (ZR) 13.0% smaller (P<0.05) in the EDP group than in the control group. In the Ca group, cell volume in the ZG was increased by 5.6% (P<0.05), while cell volumes in the ZF and ZR were decreased by 26.0% and 14.7%, respectively (P<0.05), in comparison with control values. Serum aldosterone and corticosterone concentrations were higher in the EDP-treated (by 27.8% and 19.8%, respectively) and Ca-treated (by 80.0% and 24.1%, respectively) groups in comparison with the control group (P<0.05). These data suggest that EDP and Ca treatments have stimulatory effects on the ZG and ZF, but inhibitory effects on the ZR in middle-aged female rats.

ACE (I/D), ACTN3 (R/X), PPARGC1A (Gly482Ser) and PPARA (G/C) polymorphisms have been linked to the success in power-oriented sports through the intermediate phenotypes. The study involved 193 Lithuanian elite athletes and 250 controls. The measured phenotypic variables included short-term explosive muscle power (STEMP) and anaerobic alactic maximum power (AAMP). ACE DD genotype was more common among endurance athletes compared to the power athletes. The ACTN3 genotype frequencies of the elite athletes differed from those of non-elite athletes; however, there were no differences among the athletes and the control group across the PPARGC1A Gly482Ser genotypes. The frequency of PPARA CC genotype increased with the growing skill level of athletes (non-elite 2%, sub-elite 7.7%, elite 11.6%). The STEMP and AAMP were higher in the males than females and they were also higher in the power-oriented group compared to the endurance sports group. Success in power sports can be attributed to the ACE II, PPARGC1A SerSer, PPARA CC genotype in association with phenotypic characteristics such as AAMP and STEMP. ACTN3 XX genotype may not be critical but rather additive to endurance performance. The results show that high muscle power depends on both environmental and genetic factors.

Best available descriptions of malaria incidence and mortality dynamics are important to improve and evaluate the implementation of programs to monitor (e.g., remote sensing) and control disease, especially in endemic zones. High-frequency (e.g., semi-annual and seasonal) cycles in malaria incidence have been observed in various countries and they coincide with cycles in the natural environment (e.g., temperature, heliogeophysical activity, etc.). However, neither trend nor cyclical oscillations beyond a 6-month (0.5-year) period for this vector-borne disease were reported in a recent analysis on monthly notifications in Burundi for the years 1997–2003. Since the examination of graphical plots indicated an eventual existence of trans-year (multiannual) variations, we further analyzed the same data in more detail. Here we explore whether low-frequency cycles (beyond seasonality) might exist (e.g., trans-year cycles with periods of 13–24 months or longer). Monthly incidence rate per 100 inhabitants from the Province of Karuzi, Burundi, over the years 1997–2003 was analysed. The exploration of underlying chronomes (time structures) was done by linear and non-linear parametric regression models, autocorrelation, spectral analysis (e.g., fast Fourier transforms), periodogram regression analysis (PRA) and wavelet transform (WT). By using a periodogram regression analysis, we describe a multicomponent cyclic chronome with periods T>12 months (19 and 86 months, all at P<0.05). Notably, the strongest cyclic pattern in the periodogram of the detrended malaria rates (whereas the peak was suppressed and beyond the semi-annual cycle of 6 months) was ≈1.5–1.6 years (T=19.0 months, R=0.32). A dynamic pattern of “shortening” of the length (period) of the cycles was observed during the pre-epidemic interval (from 8–9 to 5–6 months and from 20–22 to 16–18 months in years 1997–2000) that can be used to anticipate a forthcoming incidence increase and epidemic levels of malaria at a regional level. Indeed, these cycles in malaria incidence correspond to cyclic components of heliogeophysical activity (HGA) such as the sunspot cycle impulses of 0.5–2.0 years as well as the quasi-biennial solar magnetic cycle of 1.5–2.5 years and further, detailed analyses are warranted to investigate such relationships. A multicomponent dynamic cyclical pattern of malaria incidence variations in Burundi (1997–2003) exists thus allowing further, more specific analyses and modelling as well as correlations with similar environmental cycles to be explored. These results might also contribute to better estimates for forecasting, prevention and understanding of malaria dynamics and aetiology.

The objective of this study was to evaluate the effect of the light emitting diode (LED) spectra on the antioxidant properties of sprouted wheat (Triticum aestivum L.), radish (Raphanus sativus L.), and lentil (Lens esculenta Moenh.) seeds. Lighting experiments were performed under controlled conditions (PPFD - 100 μmol m−2 s−1; 12 h photoperiod; 27°C). The LED conditions used were: L1 - 638 nm; L2 - 455 nm, 638 nm, 669 nm, 731 nm (basal components); L3 - basal + 385 nm; L4 - basal + 510 nm and L5 - basal + 595 nm. Wheat and lentil sprouts were shown to accumulate less phenolic compounds and were more sensitive to light spectral differences when compared to radish sprouts. The antioxidant properties and contents of antioxidant compounds in seeds germinated in the dark were significantly lower than LED treated seeds. The higher content of total phenols and significant increase in alpha-tocopherol and vitamin C concentration resulted in altered DPPH free-radical scavenging capacity. Therefore we conclude that the LED spectra, based on basal components supplemented with green (510 nm) light can improve the antioxidant properties of sprouted seeds of lentil and wheat. The highest antioxidant properties of radish seeds were caused by radiation with supplemental amber (595 nm) light.

The effect of the natural compound S-methylmethionine (SMM) on the functioning of the photosynthetic apparatus, the efficiency of photosynthesis and the synthesis of stress-induced phenoloids and anthocyanins involved in defence was investigated in young maize plants exposed to moderate and severe chilling stress. Damage to PSII was observed as a reduction in the value of variable fluorescence (Fv/Fm) which could be detected even after few hours of mild chilling stress. At temperatures below 10°C, the reduction in Fv/Fm was more pronounced. Changes in the value of net photosynthesis exhibited a similar tendency. SMM has a moderating effect on this reduction and its protective effect was more pronounced under long-lasting chilling stress and at the lowest temperatures. Monitoring of fluorescence intensities and ratios correlated with the levels of stress defence compounds. The fluorescence intensities were found to increase over the course of chilling stress in response to SMM, with the highest values being recorded in plants exposed to the longest period of stress. A similar tendency was observed for the quantity of anthocyanins. The results confirm the complex role of SMM, which is manifested both in preserving the ability of the photosynthetic apparatus to function and in stimulating the synthesis of metabolites involved in stress defence.

The aim of this study is to investigate the toxic effect of PCZ, a triazole fungicide commonly present in surface and ground water, on the ROS defense system and Na+-K+-ATPase in gills of rainbow trout exposed to sublethal concentrations (0.2, 50 and 500 μg L−1) for 7, 20 and 30 days. After prolonged exposure of PCZ at higher test concentrations (50 and 500 μg L−1), oxidative stress was apparent as reflected by the significant higher ROS levels in fish gill, as well as the significant inhibition of SOD and CAT activities. In addition, Na+-K+-ATPase activities were significantly lower than those of the control with increasing PCZ concentration and prolonged exposure period. The results of this study indicate that chronic exposure to PCZ has altered multiple physiological indices in fish gill; however, before these parameters are used as unique biomarkers for monitoring residual pharmaceuticals in aquatic environments, more detailed laboratory experiments need to be performed.

The aim of this study was to compare the daily rhythm of reactive oxygen metabolites (hydroperoxides), and serum barrier to oxidation in five different mammal species. Five female Comisana sheep, five female Maltese goats, five female Bruna cows and five female Thoroughbred horses were housed separately in boxes equipped with an opening window and five female Blue Vienna rabbits were individually housed in metallic cages. All animals were kept under natural photoperiod and indoor environmental conditions. Blood samples were collected every 3 h over a 48 h period for the assessment of hydroperoxides, antioxidant barrier (Oxy-ads) and thiol-antioxidant barrier (SHp). A two-way for repeated measures ANOVA showed a significant effect of time of day and different species on all studied parameters. Daily rhythmicity of hydroperoxides, Oxy-ads and SHp were observed in all studied species. Nocturnal acrophases were observed in sheep, goats and rabbits, diurnal acrophases were observed in cattle and horse. We conclude that there is a synergism of the daily rhythms of hydroperoxides and anti-oxidant power in the different species studied, and that this synergism is typical of each species.

Climacostol is a resorcinol derivative that is produced by the ciliate Climacostomum virens. Exposure to purified climacostol results in lethal damage to the predatory ciliate Dileptus margaritifer and several other ciliates. To elucidate the mechanism of climacostol toxic action, we have investigated the effects of this compound on the swimming behavior of Tetrahymena thermophila and the respiratory system of isolated rat liver mitochondria. When added to living T. thermophila cells, climacostol markedly increased the turning frequency that was accompanied by a decrease in swimming velocity and subsequently by cell death. Observations by DIC and fluorescence microscopy showed morphological alterations in climacostol treated T. thermophila, indicating that climacostol might exert cytotoxic action on this organism. In the experiment with isolated rat liver mitochondria, climacostol was found to inhibit the NAD-linked respiration, but had no apparent effect on succinate-linked respiration. This finding indicates that climacostol specifically inhibits respiratory chain complex I in mitochondria. The combination of results suggest that the inhibition of mitochondrial respiration may be the cytotoxic mechanism of climacostol’s defenses against predatory protozoa.

The present work represents the first karyological and molecular characterisation of Sphaerium solidum, a rare European clam. Specimens of S. solidum were collected in Lithuania and Hungary. The modal diploid chromosome number found in both populations was 2n=30. Small, biarmed B chromosomes were found in 42.3% of cells studied in clams from Lithuania and in 11.8% of cells in clams from Hungary. Comparative analysis revealed no significant (P<0.05) interspecific differences in chromosome morphology of S. solidum and that of previously studied S. corneum. DNA sequence analyses of S. solidum showed no interpopulation differences in ITS1; moreover, only one site was different from ITS1 of S. corneum. However, differences in mitochondrial 16S sequence of S. solidum were revealed: two haplotypes in Lithuania and three in Hungary were identified. The genetic characteristics revealed in this study do not support ascription of S. solidum and S. corneum to different subgenus, Cyrenastrum and Sphaerium s. str., respectively. Comparative cytogenetic analysis disclosed that the chromosome morphology could be conserved in some sphaeriid species during speciation despite the fact that most other species in this family undergo radical karyotypic differentiation.

Ecological investigations of long-legged flies (Dolichopodidae) were carried out in wet meadow wetlands near České Budějovice, Czech Republic. Sampling was performed during the adult flies’ seasonal activity (March–October) in 2002, 2003 and 2004 using yellow pan traps, Malaise traps, emergence traps, and by sweeping. Altogether 5,697 specimens of 78 species of Dolichopodidae were collected, identified and analysed. The study examined community structure, species abundance, and diversity (Shannon-Weaver’s index - H’; Sheldon’s equitability index - E). Chrysotus cilipes, C. gramineus and Dolichopus ungulatus were the most abundant species in all three years. Species richness and diversity seem strongly affected by soil moisture.