Technical means for objectification of medical treatments in the area of the deep stabilisation spinal system

Information regarding two versions of an instrument called a muscle dynamometer, which enables detailed information about muscle activity in the deep stabilisation spinal system (DSSS), presented in this article. The MD01 (muscle dynamometer ver. 01) is a simple electromechanical instrument that allows measurement of muscle activity in two areas of the lumbar spine region. Measurements on patients have confirmed the usefulness of quantifying the initial state of a patient before rehabilitation as well as monitoring rehabilitation treatment; the MD01 is a suitable device for obtaining these measurements. However, a new and improved version of the MD01, the MD02, has been developed. The MD02 allows measurements in four different body regions and now has a PC interface, which allows achieving of patient information and data export for use with statistical software.     

The multiple T-maze in vivo testing of the neuroprotective effect of humanin analogues

Humanin (HN) and its analogues have been shown to protect cells against death induced by various Alzheimer's disease (AD) genes and amyloid-beta-peptides in vitro; the analogues [Gly(14)]-HN and colivelin have also been shown to be potent in reversing learning and memory impairment induced by scopolamine or quinuclidinyl benzilate (QNB) in mice or rats in vivo using the Y-maze or multiple T-maze tests. This paper describes the activity of new peptides of the HN family, after i.p. administration, on QNB-induced impairment of spatial memory in the multiple T-maze test in rats. The following peptides have been studied: HN analogues truncated either on the C- or N-terminus, or analogues having a tert-Leu in place of Leu in the central part of the molecule, the active HN core PAGASRLLLLTGEIDLP (RG-PAGA) and its analogues having three or five leucines instead of four, and finally the recently described hybrid peptide colivelin (i.e. a peptide having the activity-dependent neurotrophic factor SALLRSIPA attached to the N-terminus of the active RG-PAGA) and its des-Leu- and plus-Leu-analogues. While the truncated analogues and most of the tert-Leu containing analogues were devoid of activity, the analogues of the RG-PAGA were active, i.e. they reversed the impairment of spatial memory irrespective of the number of Leu present in their sequence. The highest activity was shown by colivelin and its des-Leu-analogue. These results demonstrate the potential of HN analogues in the modulation of the cholinergic system, which plays an important role in the cognitive deficits associated with AD and other neurodegenerative diseases.     

Effects of chronic food restriction and treatments with leptin or ghrelin on different reproductive parameters of male rats

The existence of a close relationship between energy status and reproductive function is well-documented, especially in females, but its underlying mechanisms remain to be fully unfolded. This study aimed to examine the effects of restriction of daily calorie intake, as well as chronic treatments with the metabolic hormones leptin and ghrelin, on the secretion of different reproductive hormones, namely pituitary gonadotropins and prolactin, as well as testosterone, in male rats. Restriction (50%) in daily food intake for 20 days significantly reduced body weight as well as plasma PRL and T levels, without affecting basal LH and FSH concentrations and testicular weight. Chronic administration of leptin to rats fed ad libitum increased plasma PRL levels and decreased circulating T, while it did not alter other hormonal parameters under analysis. In contrast, in rats subjected to 50% calorie restriction, leptin administration increased plasma T levels and reduced testis weight. Conversely, ghrelin failed to induce major hormonal changes but tended to increase testicular weight in fed animals, while repeated ghrelin injections in food-restricted males dramatically decreased plasma LH and T concentrations and reduced testis weight. In sum, we document herein the isolated and combined effects of metabolic stress (50% food restriction) and leptin or ghrelin treatments on several reproductive hormones in adult male rats. Overall, our results further stress the impact and complex way of action of different metabolic cues, such as energy status and key hormones, in reproductive function also in the male.     

Lateralization of hippocampal nitric oxide mediator system in people with Alzheimer disease, multi-infarct dementia and schizophrenia

There is evidence that brain lateralization underlying hemispheric specialization can be observed also at biochemical level. However, hemispheric differences in nitric oxide mediator system have not yet been evaluated. The hippocampus and planum temporale are highly asymmetrical regions but the degree of their laterality is altered in demented or psychotic people. In the study, l-glutamate/l-arginine/l-citrulline concentrations, nitric oxide synthase activities/expressions and nitrites/nitrates levels were estimated in autoptic hippocampi. Right/left laterality in endothelial synthase activity and in nitrites/nitrates was observed in controls. Lateral changes were estimated in patients with Alzheimer disease (a marked increase in activities of constitutive synthases and in expression of inducible enzyme in the left side) and schizophrenia (an increase in activities of all enzymes especially in the right side). Significant shifts from positive to negative correlations were found between laterality of some components of nitric oxide pathway and of planum temporale volumetry under pathological conditions. The hippocampal nitric oxide system appears to be globally right/left lateralized, especially via actions of highly asymmetrical endothelial synthase. The results suggest a specific involvement of all synthases in the development of selected diseases and show that lateral analyses are of sufficient sensitivity to reveal subtle links. The volumetric asymmetry of the planum temporale as a marker of handedness is not probably simply linked to brain laterality at biochemical level but reflects alterations due to pathological processes.     

Overexpression of P-glycoprotein in L1210/VCR cells is associated with changes in several endoplasmic reticulum proteins that may be partially responsible for the lack of thapsigargin sensitivity

L1210/VCR cells, which express an abundant amount of P-glycoprotein (P-gp), were found to be resistant to thapsigargin--an inhibitor of sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase (SERCA). In the current paper, we have studied the possible differences among L1210 and L1210/VCR cells in expression of endoplasmic reticulum proteins involved in the regulation of calcium homeostasis and calcium-dependent processes. Amounts of mRNA encoding both calcium release channels (ryanodine receptor channels--RyR and IP3-receptor channels--IP3R) were found to be at similar levels in sensitive and resistant cells. However, mRNAs encoding IP3R1 or 2 were decreased in resistant cells cultivated in the presence of VCR (1.08 micromol/l), while mRNA encoding RyR remained unchanged. The amount of mRNA for SERCA2 was decreased in resistant cells when compared with sensitive cells. This decrease was more pronounced when resistant cells were cultivated in the presence of vincristine (VCR). Calnexin was found to be less expressed at the protein level in resistant as in sensitive cells. The level of mRNA encoding calnexin was decreased only when resistant cells were cultivated in the presence of VCR. Calnexin was found to be associated with immature P-gp in resistant cells. Thus, differences exist between sensitive and resistant cells in the expression of endoplasmic reticulum proteins involved in the control of intracellular calcium homeostasis or calcium-dependent processes. These changes may be at least partially responsible for the lack of sensitivity of resistant cells to thapsigargin.     

Angiopoietin-like protein 4: development, analytical characterization, and clinical testing of a new ELISA

The aim of our work was to develop an assay for the determination of angiopoietin-like protein 4 (Angplt4) in human blood, and to investigate its levels in healthy volunteers and donors suffer from metabolic syndrome. We developed and evaluated the sandwich ELISA method for the quantitative determination of human Angplt4 in serum samples. We conducted also the pilot study on individuals with metabolic syndrome or familiar hypercholesterolemia and healthy probands and measured blood pressure, waist circumference, Angplt4 serum levels, serum cholesterol, triglycerides, HDL-cholesterol, LDL-cholesterol, insulin, glucose, A-FABP and calculate BMI and QUICKI insulin sensitivity index. In the study on 30 healthy volunteers we demonstrated that sex or age is not the determinant for Angplt4 serum values. Furthermore, we tested 115 individuals with metabolic syndrome and found that probands with metabolic syndrome did not differ in Angplt4 values than healthy individuals from the first study (medians 8.7 vs. 8.1 ng/ml, p = 0.6). Individuals with metabolic syndrome did not differ in sex or age from healthy. Angplt4 values correlated with the HDL-cholesterol (r = -0.25; p < 0.01), FGF-21 (r = 0.23, p < 0.01), glucose (r = 0.17; p = 0.03), uric acid (r = 0.17; p = 0.49), lipocalin-2 (r = 0.23, p < 0.01), triacylglycerols (r = 0.25; p < 0.01) and number or characters of metabolic syndrome (r = 0.21; p < 0.01). No significant correlation was found between serum Angplt4 and BMI, WC or QUICKI. However, we performed stepwise regression and we found that Angplt4 was not an independent marker for metabolic syndrome. The patients from the metabolic syndrome group suffering diabetes mellitus (n = 83) did not differ in serum Angplt4 from the group of healthy patients, too. The pilot study supports the hypothesis about the role of Angplt4 as a new class of lipid metabolism modulator. Their values could be a new key predictors of metabolic syndrome. Further research is necessary to confirm our findings in individuals with dyslipidemia, obesity, coronary artery diseases and different medication in order to assess Angplt4 value as a risk predictor of accelerated atherosclerosis.     

Response of cytokinin pool and cytokinin oxidase/dehydrogenase activity to abscisic acid exhibits organ specificity in peas

Changes in cytokinin pool and cytokinin oxidase/dehydrogenase activity (CKX EC: 1.5.99.12) in response to increasing abscisic acid (ABA) concentrations (0.5–10 μM) were assessed in the last fully expanded leaves and secondary roots of two pea (Pisum sativum) varieties with different vegetation periods. Certain organ diversity in CKX response to exogenous ABA was observed. Treatment provoked altered cytokinin pool in the aboveground parts of both studied cultivars. Specific CKX activity was influenced significantly basically in roots of the treated plants. Results suggest that ABA-mediated cytokinin pool changes are leaf-specific and involve certain root signals in which CKX activity presents an important link. This enzymatic activity most probably regulates vascular transport of active cytokinins from roots to shoots.