Glycosphingolipids of rabbit endometrium and their changes during pregnancy.

The glycolipids of nonpregnant and pregnant rabbit endometrium were characterized using a combination of biochemical and immunochemical techniques. Quantitative analyses indicated a 70% decline in acidic glycolipid (ganglioside) content during early pregnancy (day 6), and a 2.5-fold increase in neutral glycolipid content during later pregnancy (day 26). The major gangliosides of rabbit endometrium were identified by thin-layer chromatography as GM3 and GD3, with minor amounts of GM1, GD1a and GT1b. The major neutral glycolipids were identified similarly as globo-series structures Gb3 and Gb4. Monoclonal antibodies (mAbs) directed to glycolipid antigens permitted the detection of additional glycolipid species, including sialylated, sulfated and fucosylated lacto-series structures. Difucosyl Ley structure (defined by mAb AH-6) and sulfated-galactosyl structure (defined by mAb VESP 6.2) were identified by indirect immunofluorescence along the luminal surface of the endometrium during the implantation period. Rapid changes in the glycolipid composition of endometrial cells during early pregnancy may facilitate embryo adhesion and trophectoderm outgrowth during implantation.     

Identification of markers for nipple epidermis: changes in expression during pregnancy and lactation

In vertebrates, specific regions of skin crucial for interaction with and manipulation of elements in the environment are characterized by specialized epidermis. Regions of specialized epidermis show distinct patterns of cellular differentiation and express specific keratins that provide an increased ability to withstand mechanical strain. The nipple, which must endure the mechanical strain of nursing, is a type of specialized epidermis. The entire ventral skin of the keratin 14 promoter driven PTHrP mouse provides a model for nipple development. To identify novel markers for this specialized epidermis, we have used two-dimensional (2-D) gels, mass spectrometric protein identification, Western blotting and immunohistochemistry to compare intermediate filament preparations from the nipple-like K14-PTHrP ventral skin to that of wild-type littermates. We identified 64 spots on 2-D gels that were increased in expression in the nipple-like skin of the female K14-PTHrP mouse and 11 spots that were elevated in the wild type. Microsequencing suggested that K17 and epiplakin were among the proteins with the greatest increase in expression in the K14-PTHrP ventral skin. Using Western blots and immunohistochemistry, we evaluated the expression of these proteins as well as K6 in the wild-type nipple, K14-PTHrP ventral skin and wild-type ventral skin. In addition, we found that the expression of K6 was minimally changed in the pregnant and lactating nipple, but the expression of a previously identified marker, K2e, was reduced during lactation. Using a model of the mechanical strain induced by nursing, we found that K2e but not K6 expression was responsive to this condition. The identification of epidermal markers and their expression patterns will provide insight into the cellular differentiation patterns of the nipple and the underlying epidermal-mesenchymal interactions that direct this differentiation.     

Serum levels of irisin in gestational diabetes mellitus during pregnancy and after delivery

ObjectiveIrisin has recently been introduced as a novel an exercise-inducible myokine which improves glucose metabolism in mice. However, regulation of circulating irisin in gestational diabetes mellitus (GDM) and in the peripartal period has not been assessed so far.MethodsCirculating irisin was quantified in 74 GDM patients and in 74 healthy, pregnant, gestational age-matched controls. In a subset of these patients (44 GDM, 41 controls), postpartum follow-up data were also available. In a second study population of 40 healthy women with singleton pregnancies undergoing elective Cesarean section, irisin was assessed in maternal serum before and within 24 h after delivery, as well as in umbilical cord blood and in placental tissue.ResultsIn the first study population, median [interquartile range] irisin levels were significantly higher in GDM patients as compared to controls after delivery (previous GDM: 446.3 [146.9] μg/l; controls: 378.0 [111.4] μg/l) but not during pregnancy (GDM: 482.1 [132.1] μg/l; controls: 466.6 [178.0] μg/l). Interestingly, fasting insulin (FI) was independently and positively associated with serum irisin in multivariate analysis during pregnancy. In agreement with these findings, relative changes (ratio) of FI independently and positively predicted relative changes of irisin (ratio) in the second study population.ConclusionsThe myokine irisin is independently associated with FI in pregnancy. The physiological significance of these findings needs to be assessed in future experiments.     

Biochemical markers of bone turnover and their association with bone marrow lesions

Introduction

Our objective was to determine whether markers of bone resorption and formation could serve as markers for the presence of bone marrow lesions (BMLs).

Methods

We conducted an analysis of data from the Boston Osteoarthritis of the Knee Study (BOKS). Knee magnetic resonance images were scored for BMLs using a semiquantitative grading scheme. In addition, a subset of persons with BMLs underwent quantitative volume measurement of their BML, using a proprietary software method. Within the BOKS population, 80 people with BMLs and 80 without BMLs were selected for the purposes of this case-control study. Bone biomarkers assayed included type I collagen N-telopeptide (NTx) corrected for urinary creatinine, bone-specific alkaline phosphatase, and osteocalcin. The same methods were used and applied to a nested case-control sample from the Framingham study, in which BMD assessments allowed evaluation of this as a covariate. Logistic regression models were fit using BML as the outcome and biomarkers, age, sex, and body mass index as predictors. An receiver operating characteristic curve was generated for each model and the area under the curve assessed.

Results

A total of 151 subjects from BOKS with knee OA were assessed. The mean (standard deviation) age was 67 (9) years and 60% were male. Sixty-nine per cent had maximum BML score above 0, and 48% had maximum BML score above 1. The only model that reached statistical significance used maximum score of BML above 0 as the outcome. Ln-NTx (Ln is the natural log) exhibited a significant association with BMLs, with the odds of a BML being present increasing by 1.4-fold (95% confidence interval = 1.0-fold to 2.0-fold) per 1 standard deviation increase in the LnNTx, and with a small partial R² of 3.05. We also evaluated 144 participants in the Framingham Osteoarthritis Study, whose mean age was 68 years and body mass index was 29 kg/m², and of whom 40% were male. Of these participants 55% had a maximum BML score above 0. The relationship between NTx and maximum score of BML above 0 revealed a significant association, with an odds ratio fo 1.7 (95% confidence interval = 1.1 to 2.7) after adjusting for age, sex, and body mass index.

Conclusions

Serum NTx was weakly associated with the presence of BMLs in both study samples. This relationship was not strong and we would not advocate the use of NTx as a marker of the presence of BMLs.     

Changes in lipid peroxidation during pregnancy and after delivery in rats: effect of pinealectomy

Pregnancy is a physiological state accompanied by a high energy demand of many bodily functions and an increased oxygen requirement. Because of the increased intake and utilization of oxygen, increased levels of oxidative stress would be expected. In the present study, the degree of lipid peroxidation was examined in different tissues from non-pregnant and pregnant rats after the delivery of their young. Melatonin and other indole metabolites are known to be direct free radical scavengers and indirect antioxidants. Thus the effect of pinealectomy at 1 month before pregnancy on the accumulation of lipid damage was investigated in non-pregnant and pregnant rats after the delivery of their young. Malonaldehyde and 4-hydroxyalkenal concentrations were measured in the lung, uterus, liver, brain, kidney, thymus and spleen from intact and pinealectomized pregnant rats soon after birth of their young and at 14 and 21 days after delivery. The same parameters were also evaluated in intact and pinealectomized non-pregnant rats. Shortly after delivery, lipid oxidative damage was increased in lung, uterus, brain, kidney and thymus of the mothers. No differences were detected in liver and spleen. Pinealectomy enhanced this effect in the uterus and lung. It is concluded that during pregnancy high levels of oxidative stress induce an increase in oxidative damage to lipids, which in some cases is inhibited by the antioxidative actions of pineal indoles.     

Human beta-casomorphin-8 immunoreactive material in the plasma of women during pregnancy and after delivery

A method for the extraction of human beta-casomorphin-8 immunoreactive material from human plasma and a radioimmunoassay for its determination in the plasma extracts were developed. Blood was collected from 34 men, from 35 non-pregnant women, from 35 pregnant women and from 138 women after delivery and plasma extracts were assayed for the presence of human beta-casomorphin-8 immunoreactive materials. No human beta-casomorphin-8 immunoreactive material was detected in the plasma of men or non-pregnant women, whereas such material was found in the plasma of 26 out of 35 pregnant women and in the plasma of 100 out of 138 women after parturition. Material collected from women after delivery was characterized by gel filtration and high-performance liquid chromatography (HPLC) and was found to be of different composition in various individuals; its components, one of which coeluted with human beta-casein from the HPLC column, have apparently higher molecular weights than human beta-casomorphin-8. Some of these compounds seem to be very stable against enzymatic degradation at 37 degrees C in human plasma, whereas human beta-casomorphin-8 proved to be degraded very fast under identical conditions. A physiological significance of mammary products of the beta-casomorphin type during pregnancy or after parturition is suggested.     

Free and phospholipid-bound choline concentrations in serum during pregnancy,after delivery and in newborns

The aims of this study were to determine whether serum free choline and phospholipid-bound choline concentrations change during the pregnancy or after childbirth and to determine if the serum choline concentrations of the mother and newborn are correlated. Serum free and bound choline concentrations were 10.7 +/- 0.5 microM and 2780 +/- 95 microM in control, non-pregnant women, and rose significantly (p < 0.001) to 14.5 +/- 0.6 microM and 3370 +/- 50 microM or to 16.5 +/- 0.7 microM and 3520 +/- 150 microM after 16-20 weeks or 36-40 weeks of pregnancy, respectively. Serum free and phospholipid-bound choline fell by 14-22% (p < 0.05-01) after either vaginal delivery or caesarian section, and remained low (by 15-42%; p < 0.05-0.001) for 12 h and then rose toward the baseline within 24 h. In amniotic fluid, free choline and phospholipid-bound choline concentrations were 22.8 +/- 1.0 and 19.6 +/- 0.8 microM or 24.0 +/- 1.5 and 516 +/- 43 microM at 16-20 weeks of gestational age or at term, respectively. In newborns, serum free choline concentrations were higher (p < 0.001) and phospholipid-bound choline concentrations were lower (p < 0.001) than in their mothers. These results show that serum free choline and phospholipid-bound choline concentrations are elevated during the pregnancy, which may be required for an adequate maternal supply of choline to the fetus. These observations are clinically important to determine the ideal dietary intake of choline during the pregnancy.     

Increased bone turnover markers after renal transplantation

Bone remodeling is a process that occurs continuously in a seemingly inactive tissue like bone. Because of decreased vitamin D synthesis, phosphorus retention and decreased calcium blood concentration, patients with chronic renal failure (CRF) develop secondary hyperparathyroidism. Elevated PTH levels shifts balance between osteoblast and osteoclast activity in favor of osteoclast activity and, therefore, bone resorption. Bone metabolic disorder that affects patients with CRF is called renal osteodystrophy (ROD). We presume that renal transplantation reverses bone metabolism disorder and our goal was to establish whether osteoblast and osteoclast activity returns to the levels of healthy individuals.     

Long-term changes in medication during pregnancy

The Finnish Register of Congenital Malformations, established in 1963, rendered possible the study of changes in medication during pregnancy. The study consisted of 659 control mothers who had delivered a healthy child during the years 1964-1984. The data of this long-term follow-up study were collected by interviews at Maternal Health Care Centers after delivery and were completed by filed antenatal data. The results show a continuous decreasing trend in the usage of analgesics and tranquilizers but not in the usage of antiemetics, antibiotics, and vitamins. We believe that in Finland the publicity aimed at unnecessary medication during pregnancy has affected both the mothers and the health personnel.     

Glycosphingolipids of human myometrium and endometrium and their changes during the menstrual cycle, pregnancy and ageing

The glycolipid composition of human myometrium and endometrium was examined at various stages of maturation and reproduction. The major neutral glycolipids of both myometrium and endometrium were identified by high-performance thin-layer chromatography as globo-series glycolipids, Gb3 and Gb4. The major acidic glycolipids (gangliosides) were identified similarly as GM3 and GD3, with lesser amounts of GM1, GD1a, and GT1b. During pregnancy, GD3 expression declined in both myometrium and endometrium, whereas GM3 expression increased. Reciprocal changes in GM3/GD3 expression were mirrored by appropriate changes in the glycosyltransferases required for their synthesis; alpha 2----3sialyltransferase activity increased approximately 3-fold during pregnancy, while alpha 2----8sialyltransferase activity declined to about 20%. The results focus attention on the glycolipids of uterine tissues, their regulation, and their possible role in reproduction and fertility.     

QT dispersion and T-loop morphology in late pregnancy and after delivery

The aim of the study was to detect changes of both the QT dispersion and T-loop morphology resulting from the changed spatial position of the heart during pregnancy. Electrocardiographic and vectorcardiographic recordings were obtained from 37 healthy women 19-36 years old in the 36th to 40th week of physiological pregnancy and 2 to 6 days after delivery. The same recordings were obtained from 18 healthy women of the same age. The average QT dispersion (+/- S.D.) in normal subjects was significantly lower (34 +/- 12 ms) than in those in late pregnancy (73 +/- 18 ms) (P < 0.001). The average amplitude of T-loop (Ta) in women in late pregnancy was significantly (P < 0.001) smaller (532 +/- 98 microV) and the width of T-loop (Tw) was wider (21.24 +/- 11.48 deg) than in the control group (793 +/- 114 microV and 7.17 +/- 3.02 deg, respectively). The partial post-partum restoration of all parameters was not significant. In all groups, the QT dispersion was significantly correlated with Tw but not with Ta. According to these results we can conclude that the QT dispersion is an indirect reflection of the complete process of ventricular repolarization, reflected in the morphology of the T-loop.     

Peripheral blood concentrations of progesterone and oestradiol during human pregnancy and delivery

To evaluate the significance of progesterone and estradiol in human uterine activity during pregnancy and delivery the blood concentrations of these hormones were monitored weekly during the last trimester of pregnancy and at the onset of labour in 15 women, and before and 3 hours after the induction of term delivery in 83 parturients. Neither plasma concentrations of progesterone or estradiol nor the ratio of progesterone to estradiol changed significantly during the last trimester of pregnancy or at the onset of delivery. After the induction of delivery parturients with initial progesterone dominance (ratio of progesterone to estradiol higher than 5 before induction) demonstrated a significant fall in serum concentration of progesterone and in the ratio of progesterone to estradiol while estradiol concentration rose significantly. In estrogen dominant women (progesterone to estradiol ratio equal to or lower than 5) the serum concentration of progesterone and the ratio of progesterone to estradiol rose significantly during the 3 hours after the induction of delivery. Our results suggest that the peripheral blood levels of progesterone and estradiol do not correlate with the tissue biochemical changes which prepare the uterine cervix and myometrium for delivery. The observation that the ratio of progesterone to estradiol decreased in progesterone-dominant and increased in estrogen-dominant women stresses the importance of a well balanced equilibrium of these hormones for prostaglandin metabolism during human delivery.     

Maternal cardiovascular changes during pregnancy and postpartum in mice

Genetically altered mice may provide useful models for exploring cardiovascular regulation during pregnancy and postpartum if changes in mice mimic humans. We found in awake ICR (CD-1) mice at 17.5 days gestation that hematocrit was reduced 18%, and the pressor response to intravenous angiotensin II was reduced ~33%. Arterial pressure in awake mice was 12% lower in early pregnancy (3.5 days) than late pregnancy (17.5 days) and postpartum (3 and 17 days after delivery), whereas heart rate was 10-20% higher in the peripartum period (17.5 days gestation and 3 days postpartum). In late pregnancy, cardiac output under isoflurane anesthesia was 64% higher than in nonpregnant mice, due to a 37% increase in stroke volume and a 17% increase in heart rate. All changes P < 0.05. We conclude that, as in humans, mice exhibit hypotension in early pregnancy, and a blunted pressor response to angiotensin II, a decrease in hematocrit, and a marked increase in cardiac output in late pregnancy.     

Effect of hormonal status and metabolic changes of restricted ewes during late pregnancy on their fetal growth and development

This study investigated the effects of hormonal status and metabolic changes of restricted ewes during late pregnancy on the ovine fetus growth and development. One hundred Mongolian ewes, synchronized for oestrus and mated, were divided into three groups and offered 0.175 MJME·kgw^−0.75·d⁻¹ (Restricted Group 1, RG1), 0.33 MJME·kgw^−0.75·d⁻¹ (Restricted Group 2, RG2) and ad libitum access to feed (Control Group, CG) during their late pregnancy respectively. The results suggested that with the supply of exogenous energy decreasing during late pregnancy, maternal body weight and net body weight loss in RG2 and RG1 were lower than those of CG (Ps0.01). The insulin and IGF-1 concentrations of ewes in RG2 and RG1 tended to be lower than those of CG (P>0.05), but the GH concentrations in RG2 and RG1 were enhanced and there was significant difference between RG1 and CG on d 120 of gestation (P<0.05). The glucose concentration of ewes in RG2 and RG1 was decreased throughout the feed restriction period, and the differences were observed between RG1 and CG on d 120 of gestation (P<0.05). In addition, the nonesterified fatty acid (NEFA) and total amino acid (TAA) concentrations of ewes in RG2 tended to increase, but there was no significant difference (P>0.05). However, the NEFA and FAA concentrations of ewes in RG1 were reduced from d 90 to d 120 of gestation, then enhanced from d 120 to d 140 of gestation. During the late pregnancy, with the supply of nutrition decreasing, the negatively physiological and biochemical maternal reactions to restriction became worse, which significantly reduced the average lamb birth weight and daily growth rate of fetus in RG2 (P<0.05) and RG1 (P<0.01).     

Effect of hormonal status and metabolic changes of restricted ewes during late pregnancy on their fetal growth and development

This study investigated the effects of hormonal status and metabolic changes of restricted ewes during late pregnancy on the ovine fetus growth and development. One hundred Mongolian ewes, synchro- nized for oestrus and mated, were divided into three groups and offered 0.175 MJME·kgw-0.75·d-1 (Re- stricted Group 1, RG1), 0.33 MJME·kgw-0.75·d-1 (Restricted Group 2, RG2) and ad libitum access to feed (Control Group, CG) during their late pregnancy respectively. The results suggested that with the sup- ply of exogenous energy decreasing during late pregnancy, maternal body weight and net body weight loss in RG2 and RG1 were lower than those of CG (P<0.01). The insulin and IGF-1 concentrations of ewes in RG2 and RG1 tended to be lower than those of CG (P>0.05), but the GH concentrations in RG2 and RG1 were enhanced and there was significant difference between RG1 and CG on d 120 of gesta- tion (P<0.05). The glucose concentration of ewes in RG2 and RG1 was decreased throughout the feed restriction period, and the differences were observed between RG1 and CG on d 120 of gestation (P<0.05). In addition, the nonesterified fatty acid (NEFA) and total amino acid (TAA) concentrations of ewes in RG2 tended to increase, but there was no significant difference (P>0.05). However, the NEFA and FAA concentrations of ewes in RG1 were reduced from d 90 to d 120 of gestation, then enhanced from d 120 to d 140 of gestation. During the late pregnancy, with the supply of nutrition decreasing, the negatively physiological and biochemical maternal reactions to restriction became worse, which sig- nificantly reduced the average lamb birth weight and daily growth rate of fetus in RG2 (P<0.05) and RG1 (P<0.01).