Medium-term cardiovascular effects of high-dose growth hormone treatment in growth hormone-deficient children

AIM: To investigate the possible cardiac morphofunctional alterations inducd by prolonged and high-dose GH therapy in a group of 14 children with isolated GH deficiency. PATIENTS AND METHODS: Patients were evaluated at phase 1, after 1.1 +/- 0.6 years of treatment with GH 0.93 +/- 0.13 U/kg/week, and at phase 2, after 5.5 +/- 2.1 years of therapy 0.89 +/- 0.11 U/kg/week. At each phase left ventricular volume, mass and systolic function were evaluated by two-dimensional guided M-mode echocardiography; left ventricular diastolic function was assessed by PW-Doppler sampling of transmitral flow. RESULTS: Phase 1: diastolic blood pressure was lower (p < 0.05) and fractional shortening was not adequate for the level of afterload (stress shortening index p < 0.05) in patients compared to controls. Phase 2: diastolic blood pressure was lower (p < 0.01) and mass and mass/volume ratio were increased (mass index p < 0.05, mass/ volume ratio p < 0.05) in patients compared to controls. The increased mass/volume ratio, together with the normal systolic blood pressure, explains the reduction in peak systolic stress (p < 0.005). Among the parameters of left ventricular diastolic function, the peak E velocity/total area under mitral valve tracing and the area under E velocity/total area under mitral value tracing ratios were significantly decreased (p < 0.05). CONCLUSION: After a mean period of 5 years on high-dose GH treatment in GH-deficient children, subclinical morphofunctional alterations in the left ventricle were found.     

Problem of controls in physiology and pharmacology: Psychophysiological and morphofunctional effects of chronic saline administration

The psychophysiological and morphofunctional effects of chronic administration of saline, which is commonly used as an active control, to Wistar rats were analyzed at different levels. The active control proved to be complicated by signs of stress manifested as increased corticosterone levels, changes in the homeostatic system, blood cytometric indices, morphofunctional states of the thymus and spleen, sharp suppression of the cognitive activity, and decrease in the motivational and locomotor activities. Pain expectation developed in animals after the second saline injection in the tail-flick test—pain sensitivity sharply increased in the session prior to the injection. These signs of stress should be taken into account for interpretation of the effects in drug tests.     

Indices of the cellular reactions of the immune process in acute stress and its thymopentin correction]

The correlative analysis has determined the peculiarities of the integration of immune cells reactions under the acute stress. They are characterized by an increase in the role of polymorphonuclear leucocytes closely associated with blood superoxide dismutase activity. Thymopentin exerts an adaptive effect on the morphofunctional parameters of immune and antioxidant systems.     

Influence of cadmium ions on some morphofunctional and immune-physiological parameters of perch (<Emphasis Type="Italic">Perca fluviatilis</Emphasis>, Perciformes,Percidae) underyearlings

The changes in some morphofunctional and immune-physiological parameters in perch (Perca fluviatilis) underyearlings exposed to sublethal cadmium chloride concentration have been analyzed. The fluctuations of kidney index values and stimulating effect of toxicant upon humoral factors of nonspecific immunity have been revealed. The leucocytes ratio has been changed most sharply in the peripheral blood, kidney, and liver, but directions of changes in blood, liver, and kidney were different. Suppression of spontaneous and enhancement of induced phagocytosis by blood neutrophils were noted. In general, the observed changes correspond well to nonspecific stress response. It is concluded that the studied parameters are quite sensitive indices for assessment of environmental toxicity to fish.     

Sex-related dimorphism of the morphofunctional characteristics of the epiphysis in newborn children subjected to hypoxic impairment and asphyxia

In 72 newborn children (37 boys and 35 girls) who suffered from prenatal hypoxia and were born in an asphyxic state, we measured the level of melatonin in the umbilicial blood and observed clinical manifestations of the adaptation/stress syndrome. These data were compared with the results of morphological examination of the epiphyses from 27 stillborns (15 boys and 12 girls) who perished because of heavy prenatal hypoxia. The level of melatonin in the blood of ill newborn girls was much higher than that in boys, and both these indices were about two times higher than those in respective groups of healthy newborn children. At the same time, the pathomorphological examination showed that active epiphyseal cell units in the male fetuses were much more numerous. The results show that the epiphysis plays a significant role in determination of the sex-related dimorphism of the adaptation/stress syndrome in newborn children suffering from hypoxia- and asphyxia-evoked heavy CNS damage. The reasons and consequences of more intensive morphofunctional loading of the epiphyseal system in the male fetuses are discussed.     

Dynamics of indices of the rat endocrine and lymphatic systems during cold adaptation

A study was made of the content of corticosterone, thyroxine and triiodothyronine in the blood, of the thymic weight and cytomorphological characteristics of rat lymph nodes during prolonged cold (4-5 degrees C) adaptation. Interrelated alterations in the characteristics under study were revealed at different stages of adaptation. The morphofunctional recovery of the lymphoid tissue occurs in the phase of the increased specific stability in spite of the fact that the action of cold is continued and the blood corticosterone concentration is elevated. A new type of the endocrine-lymphoid relationships is supposed to be formed during lengthy adaptation, with this type being different from that both in the starting state and acute stress.     

The status of ovary capillaries in fetuses of White rats after irradiation in various periods of its embryogenesis

The peculiarities of reactions of blood capillaries and their cell structures in the ovary of 20-days old foetus to the irradiation in embryogenesis were revealed; it was shown for the first time that the character and direction of changes in principal morphofunctional parameters depended on the dosage, power of gamma-irradiation and the age of the developing organism by the exposure moment.     

Myocardial remodeling and arrhythmogenesis in moderate cardiac hypertrophy in rats

In 47 male adult Wistar rats with 4-wk aortic coarctation (AC) and 39 age-matched sham-operated rats (SO) chronically instrumented for telemetry electrocardiogram recording, we investigated the mechanisms of arrhythmogenesis in moderate cardiac hypertrophy, with an approach from "in vivo" toward the cellular level, analyzing 1) stress-induced cardiac arrhythmias in all rats and 2) myocardial fibrosis in 35 animals and action potential duration and density of hyperpolarization-activated current in 19 others at the ventricular level. Aortic banding increased arterial blood pressure, cardiac weight, and ventricular myocyte volume by 11, 25, and 14%, respectively (P < 0.001-0.05). Ventricular arrhythmias occurred at similar rates in AC and SO rats throughout the stress procedure. Action potential duration and hyperpolarization-activated current were about twice as great and myocardial fibrosis about four times greater in AC animals (P < 0.005-0.05). Electrocardiogram data also revealed more supraventricular arrhythmias in AC rats during the baseline period and after stress and fewer atrioventricular block episodes after stress (P < 0.05). Thus stress-induced supraventricular and atrioventricular nodal, but not ventricular, arrhythmias were affected in moderate cardiac hypertrophy when ventricular morphofunctional alterations were evident.     

The electron microscopic characteristics of stress lung

The influence of long-term (6 hours) immobilization stress on morphofunctional state of lung air-blood barrier was studied in experiments of the rats. It was shown that stress provoked the marked ultrastructural changes in the lungs, which were as follows: lung tissue oedema, pronounced thickening of lung air-blood barrier and its separate layers, edema-hemorrhagic syndrome, alveolar epithelial injury, disturbance of lung surfactant systems. Such a pathological complex may be designated as a "stress lung".     

Changes of Somatotropin Concentration in Blood Serum of Juvenile Russian Sturgeon <Emphasis Type="Italic">Acipenser gueldenstaedtii</Emphasis> (Acipenseriformes) During Adaptation to Hyperosmotic Medium

To study the role of somatotropin (ST) in osmotic regulation of anadromous acipenserids, the dynamics of hormone concentration in blood serum of juvenile Russian sturgeon Acipenser gueldenstaedtii Brandt (age 4 months, average length 16.9 cm, average weight 17.1 g) during fish adaptation to hyperosmotic medium of 12.5‰ salinity (403 mOsm/l) was evaluated for the first time. During the first 24 h after the transfer of fish from freshwater to hyperosmotic medium, an increase of ST serum concentration (up to 2.06 ± 0.09 vs. 0.98 ± 0.03 pg/ml in control fish from freshwater) was observed. This increase occurs concurrently with an increase in blood serum osmolarity (up to 386.2 ± 4.0 mOsm/l vs. 218.5 ± 4.9 mOsm/l in control) resulting from the diffusion of water from the organism under new osmotic gradient, as well as with the period of morphofunctional remodelling of the osmoregulatory system corresponding to the transition of fish to hypoosmotic regulation. 24 h after the start of the experiment, fish that have shifted to hypoosmotic regulation display the adaptive decrease in osmolarity (aimed at maintaining the relative constancy of blood serum) and the ST concentration (down to 1.18 ± 0.16 pg/ml after 120 h, comparable with that in the control fish). It is concluded that during transition of juvenile Russian sturgeon to hypoosmotic regulation, ST becomes involved in morphofunctional remodelling of the osmoregulatory system concurrently with other components of this system. ST-immunopositive cells were revealed in the dorsal part of mesoadenohypophysis of Russian sturgeon juveniles by immunochemical method.     

In vitro Maturation of Cattle Oocytes Taken from Ovaries with Different Morphofunctional State

We studied the capacity of cattle oocytes taken from ovaries with different morphofunctional state for development to metaphase II in vitro. A classification of ovaries has been proposed according to their morphofunctional state: (1) ovaries with a yellow body from the last cycle, without dominating follicle, with many follicles of varying diameter; (2) ovaries with a yellow body from the last cycle, with dominating follicle (from 10 mm in diameter); (3) ovaries with a large functioning yellow body and follicles of varying diameter; (4) ovaries with a follicular cystoid formation (more than 25 mm in diameter); (5) ovaries with a yellow body from past cycles and small (1–2 mm) follicles, supposedly with a weakened hormonal function. It was shown that the morphofunctional state of ovaries determined the total number of oocytes isolated from an ovary and number of morphologically normal oocytes feasible for cultivation. At the same time, no reliable differences in the capacity for extrusion of the first polar body between the oocytes from the ovaries of different types were found in the experiments on in vitro oocytes maturation. Since the coefficient of correlation between the extrusion of the first polar body and maturation to metaphase II was in 0.95, there is every reason to believe that the capacity for development to metaphase II does not depend on the morphofunctional state of ovaries.     

Microscopic evaluation of vesicles shed by rat erythrocytes at elevated temperatures

It is hypothesized that the elevation of the temperature of the blood during heat stress may cause an increase of the shedding of erythrocyte membrane vesicles. Therefore, the increase of vesicle numbers following heat stress may be indicative of and proportional to the level heat stress. In order to test this hypothesis, erythrocytes and the vesicles shed by erythrocytes were collected from rat blood and analyzed after the elevation of body temperature by exposure to external heat. The images of erythrocytes and vesicles were analyzed by a custom light microscopy system with spatial resolution of better than 90 nm. The samples were observed in an aqueous environment and required no freezing, dehydration, staining, shadowing, marking or any other manipulation. The elevation of temperature from 36.7±0.3 to 40.3±0.4 °C resulted in significant increase of the concentration of vesicles in blood. At a temperature of 37 °C, mean vesicle concentrations and diameters found in rat blood were (1.4±0.2)×10⁶ vesicles/μL and 0.436±0.03 μm, respectively. The concentration of free vesicles increased after exposure to heat to (3.8±0.3)×10⁶ vesicles/μL. It was estimated that 80% of all vesicles found in rat blood are smaller than 0.45 μm. The increase in the number of vesicle associated with elevated temperatures may be indicative of the heat stress level and serve as diagnostic test of erythrocyte stability and heat resistance.     

In vitro maturation of cattle oocytes taken from ovaries with different morphofunctional states

We studied the capacity of cattle oocytes taken from ovaries with different morphofunctional state for development to metaphase 2 in vitro. A classification of ovaries has been proposed according to their morphofunctional state: (1) ovaries with a yellow body from the last cycle, without dominating follicle, with many follicles of varying diameter; (2) ovaries with a yellow body from the last cycle, with dominating follicle (from 10 mm in diameter); (3) ovaries with a large functioning yellow body and follicles of varying diameter; (4) ovaries with a follicular cystoid formation (more than 25 mm in diameter); (5) ovaries with a yellow body from past cycles and small (1-2 mm) follicles, supposedly with a weakened hormonal function. It was shown that the morphofunctional state of ovaries determined the total number of oocytes isolated from an ovary and number of morphologically normal oocytes feasible for cultivation. At the same time, no reliable differences in the capacity for extrusion of the first polar body between the oocytes from the ovaries of different types were found in the experiments on in vitro oocytes maturation. Since the coefficient of correlation between the extrusion of the first polar body and maturation to metaphase 2 was in 0.95, there is every reason to believe that the capacity for development to metaphase 2 does not depend on the morphofunctional state of ovaries.     

Antiulcerous efficacy of reamberin at the background of the stress ulcerogenic factor action

The effect of reamberin on morphofunctional changes in the small intestine mucous membrane due to stress ulcerogenesis was studied. Normalization of the lipid modifications in the tissue structure, evident of the drug antiulcerous properties, was observed.     

Quantitative assessment of ultrastructural reorganizations in the adrenal cortex of rats under stress following preliminary hypophysectomy

It is shown possible to develop the stress reaction without hypophysis participation by means of the quantitative analysis of morphofunctional changes in the adrenal cortex of hypophysectomized rats in the immobilization stress dynamics. The course of the reaction under the long-term irritant effect may be of phasic character but it is distinguished by some ultrastructural peculiarities.     

Morphofunctional features of lymph nodes, thyroid gland and testis of rats during adaptation reactions to stress and activation

The morphofunctional state of lymphatic nodes, thyroid gland and testis have been studied with morphometric, cell photometric and biochemical methods in experiments on adult white rats under the influence of nonspecific adaptation stress and activation reactions caused by small doses of adrenaline (125 mg/kg and 5 mg/kg). The research showed that the changes in the structure and function of the lymphatic organs under stress and activation were markedly different. If stress results in depression of functional state of these organs, the activation reaction, on the contrary, stimulates it.     

Theory of V.A. Dogiel on polymerization and oligomerization as a general integration concept

The theory of V.A. Dogiel on the significance of polymerization and oligomerization processes in the evolution of Protozoa and Metazoa is compared with the paper of I.I. Schmalhausen (1972) on factors and steps of aromorph evolution. Dogiel’s theory is considered as a general integration conception. Four steps are distinguished in the evolution of biological systems: (1) formation of morphofunctional system by units of the lower structural level, (2) polymerization of morphofunctional units of a system, (3) oligomerization of morphofunctional units of system by means of their reduction, uniting, or differentiation, (4) integration and stabilization of a system owing to development of morphofunctional connections between its parts.     

Identification of chronic stress biomarkers in dairy cows

Stress in dairy herds can occur from multiple sources. When stress becomes chronic because of a long duration and inability of animals to adapt, it is likely to deeply affect the emotional state, health, immunity, fertility and milk production of cows. While assessing chronic stress in herds would be beneficial, no real consensus has emerged from the literature regarding the indicators of interest. The goal of this study was to compare and evaluate potential biomarkers for chronic stress after inducing stress over a 4-week period through severe overstocking, restricted access to feed and isolated unusual events. A total of 30 cows were involved in the experiment and two similar groups were constituted. Over a 4-week period, the 15 cows of the stress group were housed in overstocked conditions, with 4.6 m² per cow, including resting and feeding areas. In this area, only seven individual places at the feeding area were available for the 15 cows to generate competition for feed access. Twice during the trial and over a period of 2 h, an additional stress was induced by moving cows to an unfamiliar barn and diffusion of stressing noises (dog barking). Meanwhile, the 15 cows of the control group stayed in the original barn, with more than 10 m² per cow and more individual places at the feeding area than cow number. On a weekly basis, several variables considered as potential biomarkers for chronic stress were recorded. Collected data were analysed using single trait linear repeated mixed models. No differences were observed regarding milk yield, BW of cows or body condition score but the milk loss was more pronounced in the stress group. The activity was more heterogeneous and the rumination of cows was lower in the stress group. The heart rate was lower in the stress group and showed more heterogeneity at the end of the stress period. No differences were observed regarding salivary cortisol, blood glucose, β-endorphin, thyroxine and leucocyte profile. A higher level of hair cortisol and blood fructosamine were observed in the stress group at the end of the stress period. Regarding the practical use of the highlighted biomarkers, milk loss may be an effective and easy way to detect general problems, including stress. The blood fructosamine and the hair cortisol concentrations are promising indicators to assess chronic stress in commercial farms.     

Hemodynamic force dictates endothelial angiogenesis through MIEN1-ERK/MAPK-signaling axis

It is well-recognized that blood flow at branches and bends of arteries generates disturbed shear stress, which plays a crucial in driving atherosclerosis. Flow-generated fluid shear stress (FSS), as one of the key hemodynamic factors, is appreciated for its critical involvement in regulating angiogenesis to facilitate wound healing and tissue repair. Endothelial cells can directly sense FSS but the mechanobiological mechanism by which they decode different patterns of FSS to trigger angiogenesis remains unclear. In the current study, laminar shear stress (LSS, 15 dyn/cm²) was employed to mimic physiological blood flow, while disturbed shear stress (DSS, ranging from 0.5 ± 4 dyn/cm²) was applied to simulate pathological conditions. The aim was to investigate how these distinct types of blood flow regulated endothelial angiogenesis. Initially, we observed that DSS impaired angiogenesis and downregulated endogenous vascular endothelial growth factor B (VEGFB) expression compared to LSS. We further found that the changes in membrane protein, migration and invasion enhancer 1 (MIEN1) play a role in regulating ERK/MAPK signaling, thereby contributing to endothelial angiogenesis in response to FSS. We also showed the involvement of MIEN1-directed cytoskeleton organization. These findings suggest the significance of shear stress in endothelial angiogenesis, thereby enhancing our understanding of the alterations in angiogenesis that occur during the transition from physiological to pathological blood flow.     

Nitric Oxide Synthetic Pathway in Red Blood Cells Is Impaired in Coronary Artery Disease

Background

All the enzymatic factors/cofactors involved in nitric oxide (NO) metabolism have been recently found in red blood cells. Increased oxidative stress impairs NO bioavailability and has been described in plasma of coronary artery disease (CAD) patients. The aim of the study was to highlight a potential dysfunction of the metabolic profile of NO in red blood cells and in plasma from CAD patients compared with healthy controls.

Methods

We determined L-arginine/NO pathway by liquid-chromatography tandem mass spectrometry and high performance liquid chromatography methods. The ratio of oxidized and reduced forms of glutathione, as index of oxidative stress, was measured by liquid-chromatography tandem mass spectrometry method. NO synthase expression and activity were evaluated by immunofluorescence staining and ex-vivo experiments of L-[¹⁵N₂]arginine conversion to L-[¹⁵N]citrulline respectively.

Results

Increased amounts of asymmetric and symmetric dimethylarginines were found both in red blood cells and in plasma of CAD patients in respect to controls. Interestingly NO synthase expression and activity were reduced in CAD red blood cells. In contrast, oxidized/reduced glutathione ratio was increased in CAD and was associated to arginase activity.

Conclusion

Our study analyzed for the first time the whole metabolic pathway of L-arginine/NO, both in red blood cells and in plasma, highlighting an impairment of NO pathway in erythrocytes from CAD patients, associated with decreased NO synthase expression/activity and increased oxidative stress.