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The content of amino acids - sources of gasotransmitters and the activity of enzymes of their metabolism have been studied in the placenta and amniotic fluid in full-term and complicated by preterm birth (PB). Determination of amino acids was carried out using an automatic analyzer; specific spectrophotometric methods were used to assess the activity of enzymes. The development of PB is accompanied by changes in the amino acid level already in the second trimester of pregnancy. Correlation of differently directions was found between the level of amino acids and the activity of the corresponding enzymes. The imbalance of amino acids in the fetoplacental system in PB is accompanied by a change in the production of their low molecular weight derivatives gas transmitters (NO, CO, H2S), which play an important role in the regulation of numerous metabolic processes.

The content of metal ions and proteins containing or binding these metals in amniotic fluid during different periods of physiological pregnancy and placental insufficiency (PI) was studied. The content of zinc, copper, magnesium, iron, zinc-α-2-glycoprotein, ferritin, ceruloplasmin and the activity of Ca2+, Mg2+-ATPase were estimated using spectrophotometric methods, immunoturbometric and enzyme immunoassay methods. It was found that in PI in both trimesters there is a decrease in the content of zinc, copper, iron and an increase in the level of copper. The indices of ceruloplasmin, ferritin, Ca2+, Mg2+-ATPase in PI are lower, and zinc-α-2-glycoprotein is higher than in similar periods of physiological gestation. A close correlation of different directions has been established between the level of metals and the corresponding proteins. The revealed violations obviously play a certain pathogenetic role in the development of PI, and the indicators of the ratio between metals can serve as markers for predicting the state of newborns., Competing Interests: The authors declare no conflict of interest.

The content of nuclear and membrane proteins of the placenta, as well as posttranslational modification of these proteins in physiological pregnancy and placental insufficiency (PI) were studied. Differential centrifugation, electrophoresis in polyacrylamide gel, spectrophotometric methods were used. It was found that with PN there is a decrease in the degree of production of the studied proteins of varying degrees relative to control parameters. For chromatin proteins, a more pronounced decrease in the content of non-histone proteins was found in comparison with histones. Among histone fractions, the maximum decrease was detected in the H2A fraction. The degree of change in the amount of membrane proteins depends on the detergent used. Changes in posttranslational protein modifications disorders are characterized by a decrease in the content of amine and amide (especially difficult to hydrolyze) groups and an increase in carbonyl derivatives of proteins. The revealed changes in the composition and structure of the nuclear and membrane proteins of the placenta, performing numerous regulatory functions, can be triggering links in the chain of molecular damage in the placenta at PI.

The content of vasoactive compounds and arachidonic acid in the placenta and amniotic fluid was studied in full-term (39-40 weeks) physiological pregnancy and preeclampsia (PE). The content of metabolites of nitric oxide (NOx), endothelin-1, thromboxane B2 (TxB2), prostacycline (PGI2) and arachidonic acid was estimated using spectrophotometric, immunoenzyme methods and gas-liquid chromatography. It was found that in PE the content of vasoconstrictors, of endothelin and TxB2, increased in the placenta and amniotic fluid, while the content of vasodilators, PGI2 and NOx decreased. Despite the same directionality of changes in both studied objects, the degree of changes differed and was more pronounced in the placenta. A direct or inverse correlative relationship was found between various vasoactive components (depending on their effect on vascular tone). In the case of arachidonic acid changes in its content in PE correlated with the level of vasoactive compounds, the source of which it is. The revealed differences in the ratio of vasoactive components obviously play a pathogenetic role in the development of PE and its subsequent complications.

The activity of amino acid metabolism enzymes and the content of free amino acids in the placenta during physiological pregnancy and placental insufficiency (PI) were studied using spectrophotometric methods and ion-exchange chromatography. It was found that in PI placental activity of the studied enzymes: alanine-, cysteine-e, tyrosine-, glutamino- transferase, glutathione synthetase, glutamate dehydrogenase decreases at different periods of gestation. The opposite variations occur for aspartataminotranferase and glutaminase. Similar changes are detected for amino acids synthesized or used in the course of appropriate reactions: aspartic acid, glutamic acid, glutamine, alanine, cysteine, tyrosine, arginine. The correlation between enzyme activity and amino acid content was revealed. Different periods of pregnancy are characterized by varying degrees of change, especially expressed in the second trimester, characterized by the most intense growth and development of the fetus, and its increased needs for trophic material. The revealed changes obviously play a pathogenetic role in the formation and further development of PI., Competing Interests: The authors declare no conflict of interest.

Activity of prooxidant enzymes (NADPH-oxidase and xanthine oxidase), antioxidant enzymes (superoxide dismutase (SOD) and catalase), enzymes of the glutathione-dependent systems, as well as antioxidant vitamins (retinol and a-tocopherol), lipid peroxidation products (LPP) (conjugated dienes and Schiff bases), and peroxide chemiluminescence were studied in the amniotic fluid at different periods of physiological pregnancy and placental insufficiency (PI). It was found that at PI the activity of NADPH-oxidase, xanthine oxidase increased and the activity of SOD, catalase, glutathione peroxidase, glutathione reductase, glutathione transferase and the content of fat-soluble vitamins decreased. The direct and inverse correlation between the studied pro- and antioxidant parameters and the content of LPP products, was found ro be different in the II and III trimesters of gestation. The revealed differences obviously reflect metabolic impairments in the fetoplacental complex, and the activity and level of the paremeters of redox processes can be used as tests for pre- and postnatal disorders.

The content of amino acids in maternal serum and umbilical cord blood during physiological pregnancy and placental insufficiency (PI) was estimated using ion-exchange chromatography. It was found that that the content of arginine, serine, glutamine, alanine, cysteine, methionine, tryptophan, leucine, phenylalanine and proline, which are involved in many metabolic processes necessary to maintain the normal functioning of the mother-placenta-fetus system, was decreases in maternal serum at PI. Opposite deviations have dicarboxylic amino acids, lysine, histidine, glycine, tyrosine and threonine, the number of which increases, strengthening the nitrogen imbalance. In the blood serum of the umbilical cord for most amino acids, was a similar direction of changes, but the degree of it is more pronounced. The opposite direction of changes is found for glycine, threonine, tyrosine, the content of which is reduced. The results of the study make it possible to broaden the understanding of the mechanisms of PI development and to offer informative tests for predicting the state of newborns., Competing Interests: The authors declare no conflict of interest.

The parameters of pro and antioxidant processes in the amniotic fluid in the dynamics of physiological pregnancy and preeclampsia were studied. Spectrophotometric and fluorimetric methods were used to evaluate the activity of NADPH-oxidase, xanthine-oxidase, superoxide dismutase (SOD), catalase, glutathione-dependent enzyme systems, the content of antioxidant vitamins - retinol and α-tocopherol, lipid peroxidation products (LPP) - diene conjugates and Schiff bases, and parameters of peroxide chemiluminescence. It was found that with preeclampsia there is an increase in the activity of prooxidant enzymes NADPH-oxidase and xanthine-oxidase, a decrease in the activity of antioxidant enzymes SOD, catalase, glutathione peroxidase, glutathione reductase, glutathione transferase, and the content of fat-soluble vitamins. Between pro- and antioxidant indices and the content of LPP, intensity of chemiluminescence a correlation is established, the degree of which is different in the II and III trimesters of pregnancy. The revealed changes obviously play a pathogenetic role in the formation and further development of preeclampsia, and the indicators of oxidation-reduction processes can serve as informative markers of pre- and postnatal pathology., Competing Interests: The authors declare no conflict of interest.

The content of the amino acids in the placenta during physiological pregnancy and fetal growth restriction (FGR) has been investigated my means of the method of ion-exchange chromatography. It has been found that in FGR the placental amino acid pool is characterized by a decreased content of arginine, proline, alanine, serine, cysteine, methionine, tryptophan, leucine, threonine, tyrosine, phenylalanine, glutamine and an increased content of dicarboxylic amino acids, lysine, histidine and glycine. These changes are accompanied by altered activity of some enzymes of amino acid metabolism, and the degree of these changes correlates with the level of corresponding amino acids.

Mass-spectrometric profiling of the serum in women at weeks 16-17 of gestation was carried out in order to detect proteomic predictors of preterm delivery. Changes in the production of 25 proteins (down-regulation for 13 proteins and up-regulation for 12 proteins) were detected in the sera of women whose pregnancies eventuated in premature deliveries. Among them, proteins with various regulatory functions were distinguished: antioxidant enzymes, chaperons, cytoskeleton proteins, cell adhesion molecules, and proteins involved in angiogenesis, proteolysis, transcription, inflammation processes, binding and transportation of various ligands. These results indicated the formation of proteomic imbalance as early as during trimester II, this eventually leading to premature delivery. The detected serum proteins were suggested as markers for early prediction of premature delivery.

The levels of zinc, copper, iron, and magnesium ions, and some of their binding proteins have been investigated in an amniotic fluid under the fetal growth retardation (FGR). FGR, developed under conditions of placental insufficiency, is characterized by a decrease in the content of zinc, iron, and magnesium ions and by an increase in the copper content in the amniotic fluid in the II and III trimesters of pregnancy. During these trimesters the levels of ceruloplasmin, ferritin, and Ca2+,Mg2+-ATPase were lower in FGR, while the level of zinc-a-2-glycoprotein was higher than during the same periods of normal pregnancy. Changes in the parameters studied in the amniotic fluid were associated with developmental disorders of the newborns. These changes obviously have a pathogenetic importance in the development of FGR, and the levels of metal ions and their ratio in the amniotic fluid can be used as markers of the pre- and postnatal pathology.

Metabolism of glutamine and glutamic acid has been investigated in the placenta and amniotic fluid under conditions of placental insufficiency. The development of placental insufficiency is characterized by the increased content of glutamic acid and a decrease of glutamine in both placenta and amniotic fluid. These changes changes were accompanied by changes in the activity of enzymes involved in the metabolism of these amino acids. There was a decrease in glutamate dehydrogenase activity and an increase in glutaminase activity with the simultaneous decrease of glutamine synthetase activity. The compensatory decrease in the activity of glutamine keto acid aminotransferase did not prevent a decrease in the glutamine level. The impairments in the system glutamic acid-glutamine were more pronounced during the development of premature labor.

Analysis of the spectrum of amniotic fluid proteins in physiological and abnormal pregnancy using proteomic analysis allowed detection of a number of difference proteins, that are absent or, alternatively, appear in gestosis. Among absent proteins, there were NADPH-dependent carbonyl reductase, epidermal fatty acid-binding protein, haptoglobin, calgranulins A and B. In contrast to proteomic spectrum of amniotic fluid in physiological pregnancy, 7 new proteins appear during gestosis, 3 of them were identified: C area of immunoglobulin K-chain, breast cancer metastasis suppressor-1, and protein-1 containing AIG2-like domain. Possible effects of revealed differences in proteomic spectrum on development of main disturbances during gestosis are discussed. Difference proteins detected in amniotic fluid may serve as gestosis markers.

An ion exchange chromatographic technique was used to study the content of 18 free amino acids in the amniotic fluid of women with physiological and complicated pregnancy. The amino acid spectrum of amniotic fluid in placental insufficiency was found to be characterized by the lower content of arginine, serine, glycine, alanine, cysteine, tyrosine, phenylalanine, and glutamine, which are involved in many metabolic processes required to maintain biochemical homeostasis during gestation. There was an opposite tendency for dicarboxylic amino acids and histidine, the levels of which increased, by enhancing nitrogen imbalance. The degree of the found impairments of a number of amino acids considerably increased in case of birth of babies with brain lesions, which permits use of their amniotic fluid determination to predict the neonatal status.

The proteomic analysis of the amniotic fluids of women with physiological pregnancy and pregnancy, complicated with placental insufficiency has been carried out on the II and III trimesters. The following difference in protein patterns have been recognized: i) appearance of several proteins lacking in physiological pregnancy; ii) absence of several proteins detectable during physiological pregnancy--hippocalcin-like protein 1, CDC37-like protein, NKG2D ligand 2 (II trimester), CDC37-like protein, NKG2D ligand 2 (III trimester). The established differences in the amniotic fluid spectrum, obviously, have the pathogenetic meaning in the placental insufficiency development. The revealed proteins of distinction may serve as markers of this obstetrical pathology.

Study of posttranslational changes in placental proteins revealed disorders in the intensity of their phosphorylation and carbonylation in patients with placental failure. Phosphorylation was reduced for the majority of endogenous placental proteins, substrates for cAMP- and cGMP-dependent protein kinases. An opposite dynamics was noted for oxidative modification of proteins. The content of carbonyl derivatives evaluated in spontaneous and metal-catalyzed oxidation of placental proteins was elevated in gestosis in comparison with the normal level.

30 women with physiological pregnancy and 28 women with gestosis were examined. In the early chorion obtained after abortion and on the full-term placenta the content of the epidermal growth factor (EGF), vascular-endothelial growth factor (VEGF) and their receptors were studied by means of the ELISA method. In the process of normal gestation the increase of the placental production both of the EGF and VEGF was found. During the pregnancy complicated with gestosis and miscarriage in the first trimester the content of EGF and its receptor was lower compared to the physiological values. For VEGF and its receptor opposite changes were found: the increase of quantity of the growth factor and the decrease of its receptor. In the case of gestosis and term pregnancy the content of the both growth factors and their receptors was lower than in controls. The revealed changes in production of the angiogenic growth factors and their receptors in the placenta may have the pathogenic importance in the development of gestosis.

The concentrations of vascular endothelial growth factor and endothelin in the placenta progressively increased during normal pregnancy. Production of vascular endothelial growth factor and endothelin in the placenta exceeded the normal during trimester I miscarriage and trimester III premature birth accompanied by intrauterine hypoxia. The concentration of these vasoactive substances during premature birth also increased in the umbilical cord. The compensatory decrease in the concentrations of vascular endothelial growth factor and endothelin in the placenta and umbilical cord was observed during full-term pregnancy with threatened abortion.

62 women in 38-40 weeks gestation were examined, 37 of them had normal delivery, whereas others (25) with uterine inertia, had delivery by Cesarean section. In the fetal membranes preparations nitric oxide production, interleukins -1beta and -6, arachidonic acid content and phospholipase A2 activity (limiting the rate of prostaglandin biosynthesis) were examined. In the case of uterine inertia increase of nitric oxide generation, decrease of interleukins and arachidonic acid levels and phospholipase A2 activity was found. Modulation of nitric oxide production with inhibitors and activators allowed to emphasize the role of NO in regulation of cytokine response and control of initial stages of prostaglandins synthesis.

Neuraminidase activity and levels of sialic acids and some hormones were measured in mammary secretion of women with induced pregnancy with a history of endocrine sterility. The activity of neuraminidase in the breast milk of pregnant women with galactorrhea may serve an informative prognostic test indicating intrauterine fetal death for 8-10 days.

Study of spontaneous and hydrogen peroxide-induced chemiluminescence of the blood serum of children born clinically healthy to mothers with complicated course of pregnancy showed that an increase of the total photosum of spontaneous chemiluminescence on day 3 of life may be regarded as a criterion of failure of adaptation; other criteria are the photosum value and intensity of the amplitude of flashes of induced chemiluminescence of newborn blood sera over the entire course of the neonatal period.

The fatty acid composition of plasma membranes in the placenta of induced-pregnancy females with ovarian hypofunction was studied Palmitic, stearic, and oleic acids were prevalent in the placental membranes. The content of arachidonic acid was higher that of linoleic acid which was in greater qualities in the membranous lipids of other tissues than arachidonic acid. The changes found in the fatty acid composition of placental membranous phospholipids were associated with the deviations in the levels of this organ-specific hormones progesterone and placental lactogen.

The aim of the present investigation is to study the effect of amniotic fluid myoglobin on prostaglandin synthesis by the fetal membranes. The paper presents results of radioimmunologic studies of myoglobin levels in various biological fluids during pregnancy: amniotic fluid, maternal serum samples obtained from an antecubital vein and the cervix, and neonatal urine. Amniotic fluid myoglobin levels were found to be significantly higher at term. Our results suggest that amniotic fluid myoglobin is likely to be derived from the fetus and excreted into amniotic fluid through fetal urine. Incubation of the fetal membrane with amniotic fluid, neonatal urine, and commercially available myoglobin enhanced phospholipase A2 activity, as well as arachidonic acid and prostaglandin F2 alpha production was compared to incubation with normal saline. The addition of anti-myoglobin antibodies to incubation media was found to block these effects. The results of our study show that myoglobin activates prostaglandin synthesis by the fetal membranes and stimulates the onset of labor.

When in the hypoxic pressure chamber and under high-altitude conditions, rats showed changes in the lipid profile of plasma membranes and in the activity of placental phospholipase A2. More profound changes occurred in the placental membranes of the rats staying under hypoxic conditions during placentation. Placental plasma membranes in the animals exposed to hypoxia in the second gestational half were more stable, their lipid composition was less altered.

The authors' findings evidence the fetal origin of amniotic fluid myoglobin. Myoglobin was found to activate the arachidonic acid and prostaglandin F2 alpha synthesis by fetal membranes. Possible mechanisms of amniotic fluid myoglobin effect on the initiation of labor are discussed.

Electrophoretic properties of syntrophoblast membrane proteins, solubilized by detergents, were distinctly altered under conditions of feto-placental insufficiency of endocrine genesis. Treatment of women with feto-placental insufficiency by means of hyperbaric oxygenation prevented the impairment of membrane protein composition.

In acute deficiency of oxygen inhibition of purine bases turnover as well as degradation of their high molecular precursors occurred in the system mother-placenta-fetus. Acute hypoxia was accompanied by distinct increase in content of adenine, xanthine + + guanine and uric acid in blood of pregnant rats, in placenta and blood of newborn animals. Long-term effect of hypoxia resulted in adaptation of purine metabolism. In this case production of adenosine and adenosine monophosphate was activated.

There were revealed changes in the content of free amino acids and in the activity of glutamic dehydrogenase, aspartic- and alanine-aminotransferases in the course of development of the placenta in guinea pigs. The greatest values by the indices under study were reached by the 25th--30th days of pregnancy, i.e. by the period of final formation of the placenta. By the 40th day of pregnancy the activity of the enzymes and the content of free amino acids fell, and from the 45th day persisted at a certain stable level up to the occurrence of labour.

Opposing changes were discovered in the liver and blood of rats aged 1-1 1/2 months with alloxan diabetes as regards the content of adenine, xanthine plus guanine, uric acid and the activity of adenine-, adenosine-, guanine deaminase and 5'-nucleotidase. The ratio of the activity of adenosine deaminase to that of 5'-nucleotidase correlating with the level of glycemia might be the most informative test in the diagnosis of the depth of the discovered metabolic disorders in alloxan diabetes.

The authors stated the correlation between the levels of homocarnosine in the amniotic fluid, fetal encephalopathy and the degree of fetal neurologic symptomatology.

The blood serum, liver, cerebral and pancreatic tissues of 250 rats aged 1 to 1.5 mos. were investigated. Alloxan diabetes caused profound changes in the lipid composition of various tissues, the most noticeable ones in the pancreas. Of all easily assimilable carbohydrates used as admixtures to a common ration fructose followed by xylite and sorbitol produced the most unfavorable effect on lipid metabolism. The best results were obtained by adding up glucose.

Lipid peroxidation, microviscosity, lipid fraction ratios and glycoprotein carbohydrate metabolism were investigated in syncytiotrophoblastic plasmatic membranes of patients with placental insufficiency. Changes are demonstrated in the above parameters, as compared to normal values, indicative of profound structural transformations of placental membranes. Hyperbaric oxygenation is shown to have a favorable effect on structure and properties of placental membranes.

The authors presented the results of studying NADPH-oxidase activity in the blood of neonates born to mothers with central endocrine disorders. The activity of the enzyme was detected in the blood and amniotic fluid withdrawn from the woman in birth. The relationship has been shown between the activity of NADPH-oxidase in the children's blood and their health status at birth together with a possibility to forecast the degree of the hypoxia-induced damage to the child in accordance with detecting the enzyme in the amniotic fluid.