Diabetic Placenta Research Articles

Placental growth factor and soluble Fms-like tyrosine kinase 1 in diabetic pregnancy: A possible relation to distal villous immaturity.

This study aimed to describe the prevalence of chorionic distal villous immaturity (DVI) in overt diabetic/gestational diabetic (OD/GD) women compared with normoglycemic ones and to analyze the relation of DVI index (DVII) to placental growth factor (PlGF) and soluble Fms-like tyrosine kinase 1 (sFlt-1). Three groups were studied; normoglycemics (n=21), OD (n=17) and GD (n=20). Maternal blood samples were evaluated regarding serum levels of PlGF and sFlt-1. Immunohistochemical methodologies were employed in term placentae of all subjects to assess DVII and area% of PlGF and sFlt-1 immunostaining. We found that mean Hemoglobin A1c (HbA1c) is 5.22±0.15 in normoglycemics, 6.2±0.3 in OD, and 5.70±0.23 in GD with significant differences between groups (p=0.012). DVII was significantly higher in OD (66.6±4.7) and GD (72.4±4.5) compared to controls (11.6±2.5; p=0.000). Healthy women have significantly lower levels of PlGF (86.6±14.5) compared to OD (166.6±22.4, p=0.000) and GD (150.3±23.97, p=0.000) and their placentae expressed a significantly lower area% of PlGF (6.5±0.8) compared to OD (14.8±1.0, p=0.000) and GD (18.8±1.3, p=0.000). Also, normoglycemic women have significantly lower levels of sFlt-1 (108.9±12.1) compared to OD (226.5±18.6, p=0.000) or GD (197.2±16.8, p=0.000) and their placentae expressed a significantly lower area% of sFlt-1 (3.2±0.3) compared to OD (15.4±1.7, p=0.000) and GD (16.9±1.2, p=0.000). There was significant correlation between DVII and both serum level and area% of PlGF and sFlt-1 expression in the 3 groups. This study provided a new score for evaluating DVI in normal and diabetic placentae and suggested a role for PlGF and sFlt-1 in regulation of DVI in diabetic pregnancies.

Placental protein tyrosine nitration and MAPK in type 1 diabetic pre-eclampsia: Impact of antioxidant vitamin supplementation

AimTo examine the role of placental protein tyrosine nitration and p38-Mitogen-Activated Protein Kinase α (p38-MAPKα), Extra Cellular-Signal Regulated Kinase (ERK) and c-Jun NH2-Terminal Kinase (JNK) activity, in the pathogenesis of type 1 diabetic pre-eclampsia, and the putative modulation of these indices by maternal vitamin C and E supplementation. MethodsPlacental samples were obtained from a sub-cohort of the DAPIT trial: a randomised placebo-controlled trial of antioxidant supplementation to reduce pre-eclampsia in type 1 diabetic pregnancy. Placenta from placebo-treated: normotensive (NT) [n=17], gestational hypertension (GH) [n=7] and pre-eclampsia (PE) [n=6] and vitamin-treated: NT (n=20), GH (n=4) and PE (n=3) was analysed. Protein tyrosine nitration was assessed by immunohistochemistry in paraffin-embedded tissue. Catalytic activities of placental p38-MAPKα, ERK and JNK were measured by enzyme-linked immunosorbent assay (ELISA). ResultsNitrotyrosine immunostaining was present in placebo-treated NT, GH and PE placentae, with no significant difference observed between the groups. There was a non-significant trend towards decreased p38-MAPKα activity in PE vs NT control placentae. ERK and JNK were similar among the three outcome placebo groups and vitamin supplementation did not significantly alter their activity. ConclusionNitrotyrosine immunopositivity in normotensive diabetic placentae indicates some degree of tyrosine nitration in uncomplicated diabetic pregnancy, possibly due to inherent oxidative stress and peroxynitrite production. Our results suggest that p38-MAPKα, ERK and JNK are not directly involved in the pathogenesis of type 1 diabetic pre-eclampsia and are not modulated by vitamin-supplementation.

D-chiro-inositol phosphoglycan expression in human placenta at term in diabetes

We present a histological assessment of diabetic placenta for the localization of some insulin mediators that were reported to play a major role for lipid/glycogen metabolism in human placenta. Placental metabolism is fundamental to fetal wellbeing. In fact, all maternal metabolic alterations have a profound effect on placental development with a subsequent definite impact on pregnancy outcome and fetal growth [1]. We have previously reported abnormalities in expression and activation of specific insulin-like growth factor-I receptor signaling molecules and multiple members of the MAP kinase family in human placentas of fetuses with intra-uterine growth restriction [2]. Subsequent studies on placental metabolism have focused on a family of insulin mediators, namely inositol phosphoglycans that were found to be highly expressed in diabetic and preeclamptic placentas [3]. These molecules play a major role in the regulation of the disposal of glucose by oxidative and non-oxidative routes of storage by glycogen synthesis [4]. In fact, the complexity and specificity of insulin action are determined by an integrated signaling network of independent intracellular pathways with several downstream effectors that have been shown to modulate the signal amplitude and frequency for both shortand longterm effects. Specific acquired alterations in activation of proteins involved in insulin signaling in preeclamptic placenta were shown to be associated with the accumulation of D-chiro-inositol phosphoglycan and to play a role in the insulin-resistant state that occurs in preeclampsia [5]. A disturbed insulin signaling was demonstrated in these cases and associated to low activation of insulin receptor effectors through multiple serine phosphorylations in both IRS-1 and IRS-2 [5]. In this study, placental specimens from six healthy and diabetic women at term were assessed for chiro-inositol using antibodies (mouse anti-D-chiro-inositol phosphoglycan), kindly provided by Professor Eduardo Martinez (Pamplona, Spain). A standard procedure was used for the immunohistochemical staining. The primary anti-D-chiroinositol phosphoglycan antibody was diluted 1:100 in antibody diluent (Dako, USA) and incubated for 60 min at room temperature. The percentage of positive stained controls was used as a reference for comparison. In control cases (Fig. 1a), a clear immunostaining of the syncytiotrophoblast was found (p = 0.11) with a little activity within the villous stroma (p = 0.43). The endothelium of placental vessels shows a localization of D-chiro-inositol phosphoglycan in normal placenta while in diabetic samples is weakly stained (p \ 0.01, Fig. 1b). The extravillous trophoblast in the basal plate of diabetic cases reveals also staining (p = 0.23, Fig. 1c, d). In both cases, a weak staining was found in maternal plasma, while a strong staining was found in fetal plasma. According to these findings, we may hypothesize that the placenta uptakes D-chiro inositol phosphoglycan from M. Scioscia (&) Department of Obstetrics and Gynecology, Sacro Cuore Don Calabria General Hospital, Via Don A. Sempreboni, 5, 37024 Negrar, VR, Italy e-mail: marco.scioscia@sacrocuore.it

Fractalkine (CX3CL1) and Its Receptor CX3CR1 May Contribute to Increased Angiogenesis in Diabetic Placenta

Chemokine CX3CL1 is unique, possessing the ability to act as a dual agent: chemoattractant and adhesive compound. Acting via its sole receptor CX3CR1, CX3CL1 participates in many processes in human placental tissue, including inflammation and angiogenesis. Strongly upregulated by hypoxia and/or inflammation-induced inflammatory cytokines secretion, CX3CL1 may act locally as a key angiogenic factor. Both clinical observations and histopathological studies of the diabetic placenta have confirmed an increased incidence of hypoxia and inflammatory reactions with defective angiogenesis. In this study we examined comparatively (diabetes class C complicated versus normal pregnancy) the correlation between CX3CL1 content in placental tissue, the mean CX3CR1 expression, and density of the network of placental microvessels. A sandwich enzyme immunoassay was applied for CX3CL1 measurement in placental tissue homogenates, whereas quantitative immunohistochemical techniques were used for the assessment of CX3CR1 expression and the microvascular density. Significant differences have been observed for all analyzed parameters between the groups. The mean concentration of CX3CL1 in diabetes was increased and accompanied by augmented placental microvessel density as well as a higher expression of CX3CR1. In conclusion, we suggest involvement of CX3CL1/CX3CR1 signaling pathway in the pathomechanism of placental microvasculature remodeling in diabetes class C.

Inflammatory Mediators of Angiogenesis

Inflammatory Mediators of Angiogenesis

608: Senescence in genotoxic amniocytes and stressed trophoblasts

Cellular senescence is a state of metabolic and cell cycle arrest evoked by exogenous or endogenous stressors, especially genotoxic stress. Some cases of senescence are characterized by formation of senescence-associated heterochromatin foci (SAHF). Short, dysfunctional telomeres lead to senescence. We have previously reported short telomeres in aneuploidy, intrauterine hypoxia (which causes intrauterine fetal growth restriction [IUGR]), and in uncontrolled gestational diabetes mellitus. We studied senescence in amniocytes and placentas from aneuploidic fetuses, in trophoblasts from IUGR fetuses, and from diabetic placentas, by assessing SAHF.

N-Glycosylation Pattern of Human Placental Insulin-Like Growth Factor and Insulin Receptors in Well-Controlled Pregestational Diabetes Mellitus

N-Glycosylation Pattern of Human Placental Insulin-Like Growth Factor and Insulin Receptors in Well-Controlled Pregestational Diabetes MellitusDiabetes mellitus is a complex disease that leads to alterations in the glycosylation of proteins. Insulin-like growth factor and insulin receptors are involved in the regulation of fetal and placental growth and development. In this work the N-glycans of these receptors, originating from placentas obtained from pregnancies complicated by pregestational insulin dependent diabetes mellitus, were studied. Diabetic mothers were under regular insulin therapy. Solubilised membrane samples from healthy and diabetic placentas were analysed using lectin-affinity chromatography. N-glycans bound to insulin-like growth factor and insulin receptors were studied in terms of their interaction with eleven agarose-immobilised lectins: wheat germ agglutinin, succinylated wheat germ agglutinin,Ricinus communisagglutinin I,Sambucus nigraagglutinin,Erythrina cristagallilectin,Ulex europaeusagglutinin,Lens culinarisagglutinin,Canavalia ensiformislectin,Phaseolus vulgariserythro- and leukoagglutinin andMaackia amurensisagglutinin. A very similar type of N-glycans and content of the terminal saccharide residues were found in both groups of placentas. The results of this work suggest that the tight glycemic control may prevent alterations in the glycosylation of insulin-like growth factor and insulin receptors, thus maintaining physiological homeostasis during pregnancy and fetal growth.

Histological and immunohistochemical changes in placental chorionic villi of patients with poorly controlled gestational diabetes

Background Normal placental development is essential for normal fetal development. The placenta is a complex fetal organ that plays pleiotropic roles during fetal growth. It separates the maternal and the fetal circulation. The placenta is exposed to the regulatory influence of the hormones, cytokines, growth factors, and substrates present in the circulation, and thus may be affected by changes in any of these. Gestational diabetes is one of the most prevalent medical complications of pregnancy and may cause increased fetal wastage. Aim of the work To study the structural changes in the placental chorionic villi of women with poorly controlled gestational diabetes in comparison with metabolically normal pregnant women. Materials and methods The study was carried out on placentas from 22 full-term pregnant women. All the women delivered at 38–40 weeks of gestation. Ten placentas were from normal uncomplicated pregnancies (control group) and the other 12 were from gestational diabetic pregnancies (diabetic group). The placentas were processed and examined using light and electron microscopy. An immunohistochemical study using S100 protein antibody was carried out. Results In comparison with the control group, the placentas of poorly controlled gestational diabetic mothers showed an increase in syncytial knots, partial shedding of trophoblastic microvilli, and thickening of the basement membrane of the trophoblast. Fibrinoid necrosis, villous fibrosis, and dilated congested fetal blood vessels were also observed. The frequent appearance of Hofbauer cells (placental macrophages) was observed in the diabetic placenta in comparison with the control placenta. Positive diabetic trophoblastic and stromal cells for S100 protein antibodies were observed. Conclusion It is concluded that poor control of diabetes during gestation may result in structural changes in the placentas, which may contribute toward fetal complications. Further research in this field may help in finding a solution for the evaluation of the destructive changes in diabetic placenta in the initial stages of pregnancy.

The branching pattern of villous capillaries and structural changes of placental terminal villi in type 1 diabetes mellitus

Maternal diabetes is associated with changes of the placental structure. These changes include great variability of vascularity manifested by strikingly hypovascular as well as hypervascular terminal villi. In this paper, normal placental terminal villi and pathological villi of type 1 diabetic placentas were compared concerning the structure of villous stroma, spatial arrangement of villous capillary bed and quantitative assessment of capillary branching pattern.Formalin fixed and paraffin embedded specimens of 14 normal and 17 Type 1 diabetic term placentas were used for picrosirius staining, vimentin and desmin immunohistochemistry and confocal microscopy. 3D models of villi and villous capillaries were constructed from stacks of confocal optical sections.Hypervascular as well as hypovascular villi of diabetic placenta displayed changed structure of villous stroma, i.e. the collagen envelope around capillaries looked thinner and the network of collagen fibers seemed less dense. The desmin immunocytochemistry has shown that stromal cells of hypervascular as well as hypovascular villi appeared nearly or completely void of desmin filaments. In comparison with normal villi, capillaries of hypovascular villi had a smaller diameter and displayed a markedly wavy course whereas in hypervascular villi numerous capillaries occurred in reduced stroma and often had a large diameter. The quantitative assessment of capillary branching has shown that villous capillaries are more branched in diabetic placentas.It is concluded that type 1 maternal diabetes enhances the surface area of the capillary wall by elongation, enlargement of diameter and higher branching of villous capillaries and disrupts the stromal structure of terminal villi.

274: Telomere shortening in placentas from pregnancies complicated with diabetes

ObjectiveTelomeres stabilize and protect chromosomes from fusion and degradation. They are shortened by cellular senescence and stress. Telomere shortening was reported in leukocytes of diabetic patients and seems to be linked to diabetic complications. hTERT, the catalytic component of the enzyme telomerase and telomere capture are mechanisms responsible for telomere length. Dysfunctional telomeres tend to fuse and form aggregates. Senescence is associated with changes in the nuclear chromatin known as senescence-associated heterochromatin foci (SAHFs). Our aim was to assess telomere homeostasis in placentas from pregnancies complicated with diabetes.Study DesignPlacental biopsies from third trimester pregnancies complicated with diabetes (n=12) were compared with a control group of placentas from gestational age matched uncomplicated pregnancies (n=12). Telomeric parameters were evaluated: Telomere length, aggregates, SAHFs formation and telomere capture using manual and computerized Quantitative fluorescence-in-situ hybridization (Q-FISH). The amount of hTERT was evaluated using immunohistochemistry.ResultsDiabetic placentas expressed significantly shorter telomeres with increased aggregates and SAHFs formation and also increased expression of hTERT and telomere capture. (table).Tabled 1% Trophoblasts with the following parameters:ControlDiabetesP valueClear short telomeres4.92 ± 6.4224.42 ± 22.60.013Clear long telomeres90.92 ± 8.1370.17 ± 27.010.006Aggregates0.62 ± 0.872.75 ± 1.14<0.0001Nuclei with SAHFs8.77 ± 5.3119 ± 7.930.001Increased hTERT expression25.36 ± 5.2637 ± 9.690.001Evidence of telomere capture7.82 ± 2.9515.1 ± 8.450.014 Open table in a new tab ConclusionTelomeres are shorter in placentas from pregnancies complicated with diabetes, which might influence intrauterine programming of those fetuses. ObjectiveTelomeres stabilize and protect chromosomes from fusion and degradation. They are shortened by cellular senescence and stress. Telomere shortening was reported in leukocytes of diabetic patients and seems to be linked to diabetic complications. hTERT, the catalytic component of the enzyme telomerase and telomere capture are mechanisms responsible for telomere length. Dysfunctional telomeres tend to fuse and form aggregates. Senescence is associated with changes in the nuclear chromatin known as senescence-associated heterochromatin foci (SAHFs). Our aim was to assess telomere homeostasis in placentas from pregnancies complicated with diabetes. Telomeres stabilize and protect chromosomes from fusion and degradation. They are shortened by cellular senescence and stress. Telomere shortening was reported in leukocytes of diabetic patients and seems to be linked to diabetic complications. hTERT, the catalytic component of the enzyme telomerase and telomere capture are mechanisms responsible for telomere length. Dysfunctional telomeres tend to fuse and form aggregates. Senescence is associated with changes in the nuclear chromatin known as senescence-associated heterochromatin foci (SAHFs). Our aim was to assess telomere homeostasis in placentas from pregnancies complicated with diabetes. Study DesignPlacental biopsies from third trimester pregnancies complicated with diabetes (n=12) were compared with a control group of placentas from gestational age matched uncomplicated pregnancies (n=12). Telomeric parameters were evaluated: Telomere length, aggregates, SAHFs formation and telomere capture using manual and computerized Quantitative fluorescence-in-situ hybridization (Q-FISH). The amount of hTERT was evaluated using immunohistochemistry. Placental biopsies from third trimester pregnancies complicated with diabetes (n=12) were compared with a control group of placentas from gestational age matched uncomplicated pregnancies (n=12). Telomeric parameters were evaluated: Telomere length, aggregates, SAHFs formation and telomere capture using manual and computerized Quantitative fluorescence-in-situ hybridization (Q-FISH). The amount of hTERT was evaluated using immunohistochemistry. ResultsDiabetic placentas expressed significantly shorter telomeres with increased aggregates and SAHFs formation and also increased expression of hTERT and telomere capture. (table).Tabled 1% Trophoblasts with the following parameters:ControlDiabetesP valueClear short telomeres4.92 ± 6.4224.42 ± 22.60.013Clear long telomeres90.92 ± 8.1370.17 ± 27.010.006Aggregates0.62 ± 0.872.75 ± 1.14<0.0001Nuclei with SAHFs8.77 ± 5.3119 ± 7.930.001Increased hTERT expression25.36 ± 5.2637 ± 9.690.001Evidence of telomere capture7.82 ± 2.9515.1 ± 8.450.014 Open table in a new tab Diabetic placentas expressed significantly shorter telomeres with increased aggregates and SAHFs formation and also increased expression of hTERT and telomere capture. (table). ConclusionTelomeres are shorter in placentas from pregnancies complicated with diabetes, which might influence intrauterine programming of those fetuses. Telomeres are shorter in placentas from pregnancies complicated with diabetes, which might influence intrauterine programming of those fetuses.

Alternations of phospholipid profile in placenta of streptozotocin‐induced diabetic rat

Phospholipids have important roles in many biological processes, but their role in fetal malformation in pregnancy in diabetes is unclear. Metabolic fingerprinting of placental phospholipids in pregnant streptozotocin-induced type 1 diabetic rats was performed using Fourier transform-ion cyclotron resonance mass spectrometry. Some of the fetuses from the pregnant diabetic rats exhibited ventricular septal defects. Alterations of phospholipid compositions in the diabetic rat placenta were detected. We suggest that these changes in phospholipids in the diabetic placenta might be involved in development of fetal malformation in a type 1 diabetic pregnancy.

Expression of glucocorticoid receptor and glucose transporter-1 during placental development in the diabetic rat

In various tissues, glucocorticoids (GCs) are known to downregulate glucose transport systems; however, their effects on glucose transporters (GLUTs) in the placenta of a diabetic rat are unknown. Glucocorticoid hormone action within the cell is regulated by the glucocorticoid receptor (GR). Thus, this study was designed to investigate the relationship between GR and glucose transporter expression in the placenta of the diabetic rat. Our immunohistochemical results indicated that GR and glucose transporter protein 1 (GLUT 1) are expressed ubiquitously in the trophoblast and endothelial cells of the labyrinthine zone, where maternal fetal transport takes place in the rat placenta. Expression of GR in the junctional zone of the rat placenta was detected in giant cells, and in some spongiotrophoblast cells, but not in the glycogen cells. GLUT 1 was present, especially in glycogen cells during early pregnancy, and in the spongiotrophoblast cells of the junctional zone during late pregnancy. Amounts of GR and GLUT 1 protein were increased towards the end of gestation both in the control and the diabetic placenta. However, at days 17 and 19 of gestation, only the placental GR protein was significantly increased in the streptozotocin-induced diabetic rats compared to control rats. Diabetes led to a significant decrease in placental weight at gestation day 15. In contrast, at gestational days 17 and 21, the weights of the diabetic placenta were significantly increased as compared with the controls. Moreover, diabetes induced fetus intrauterine growth retardation at gestational days 13, 17 and 21. In conclusion, the localization pattern of GR and GLUT 1 proteins in the same cell types led us to believe that there might be a relationship between GR and GLUT 1 expressions at the cellular level. GLUT 1 does not play a pivotal role in diabetic pregnancies. However, placental growth abnormalities during diabetic pregnancy may be related to the amount of GR.

Altered gene expression and spongiotrophoblast differentiation in placenta from a mouse model of diabetes in pregnancy.

Pregnancies complicated by diabetes have a higher risk of adverse outcomes for mothers and children, including predisposition to disease later in life, e.g. metabolic syndrome and hypertension. We hypothesised that adverse outcomes from diabetic pregnancies may be linked to compromised placental function, and sought to identify cellular and molecular abnormalities in diabetic placenta. Using a mouse model of diabetic pregnancy, placental gene expression was assayed at mid-gestation and cellular composition analysed at various stages. Genome-wide expression profiling was validated by quantitative PCR and tissue localisation studies were performed to identify cellular correlates of altered gene expression in diabetic placenta. We detected significantly altered gene expression in diabetic placenta for genes expressed in the maternal and those expressed in the embryonic compartments. We also found altered cellular composition of the decidual compartment. In addition, the junctional and labyrinth layers were reduced in diabetic placenta, accompanied by aberrant differentiation of spongiotrophoblast cells. Diabetes during pregnancy alters transcriptional profiles in the murine placenta, affecting cells of embryonic and maternal origin, and involving several genes not previously implicated in diabetic pregnancies. The molecular changes and abnormal differentiation of multiple cell types precede impaired growth of junctional zone and labyrinth, and of placenta overall. Regardless of whether these changes represent direct responses to hyperglycaemia or are physiological adaptations, they are likely to play a role in pregnancy complications and outcomes, and to have implications for developmental origins of adult disease.

Histological and histochemical changes in placenta of diabetic pregnant females and its comparision with normal placenta

Objective To investigate the histological and histochemical changes in placenta of diabetic pregnant females and compare them with normal placenta. Methods The histological and histochemical features of 60 placenta, 30 obtained from normal pregnant females and 30 from diabetic pregnant females, were studied. These placenta were obtained from Department of Obstetrics and Gynaecology, GSVM Medical College Kanpur and ERA's Lucknow Medical College and Hospital Lucknow. Results On histological examination, the diabetic placenta showed increased syncytial knots, fibrinoid necrosis, trophoblastic basement membrane thickening, villous stromal fibrosis, villous oedema, crowding of villi, thickening of vessel wall and fibrin deposition. On histochemical study it was found that the PAS reactivity was stronger in diabetic placenta as compared to normal. Sudan Black reactivity was higher among diabetic placenta in comparison to normal placenta. Conclusions It is concluded that distinct histological and histochemical changes could be seen in placenta of diabetic pregnant females.

Localization and distribution of wolframin in human female reproductive tract

Wolframin, a transmembrane glycoprotein of endoplasmic reticulum consisting of 890 amino acids, is encoded by the WFS1 gene, mutated in the Wolfram syndrome. This pathology, also called DIDMOAD, is an autosomal recessive disorder defined by the association of diabetes mellitus, optic atrophy, and further organ abnormalities. To gain further insight into the pathogenesis of diseases associated with WFS1 mutations, we conducted an immunohistochemical study to investigate its pattern of expression in human female reproductive tract in physiologic and pathologic conditions. For this purpose, samples of physiologic and pathologic endometrium, samples of placenta throughout pregnancy in normal and diabetic pregnant women, were used. In physiologic endometrium, we observed a light increase of wolframin from proliferative to secretory phase where wolframin was localized in the glands, stroma and cells lining blood vessels. In menopause, wolframin expression increased with a glandular and stromal localization. In pathologic endometrium, we observed an increase of wolframin expression from hyperplasia to polyps until a higher expression in carcinoma tissues. In normal placenta there was a modulation of wolframin throughout pregnancy with a strong level of expression during the first trimester and a moderate level in the third trimester. In diabetic women, the wolframin expression was strongly reduced in the third trimester of gestation. In human endometrium, wolframin seems to have a role in differentiation program. Deregulation of these functions may induce the onset of several endometrial pathologies. Moreover, in normal placenta wolframin may be required to sustain normal rates of cytotrophoblast cell proliferation during the first trimester of gestation. The decrease of wolframin expression in diabetic placentae may hypothesize that this protein is directly regulated by insulin concentration also in the placenta, suggesting that this protein physiologically maintain the glucose homeostasis in this organ.

Increase in placental apolipoprotein D as an adaptation to human gestational diabetes

The expression of apolipoprotein D (apo D), a lipocalin involved in defense mechanisms against oxidative stress, in placental tissue samples of pregnancies with gestational diabetes mellitus (GDM) was compared to non-diabetic controls. We have investigated the relationship of apo D with 4-HNE, a major propagation product of lipid peroxidation, in stressed tissues. We included 20 pregnant women with GDM and 30 women with normal ongoing pregnancies as the control group. Placentas were collected and frozen for Western blot or included in paraffin for immunohistochemistry. The intensity of immunostaining was higher for apo D and 4-HNE in GDM samples; however, the differences in expression between the groups was more intense for apo D. Positive signals for both antibodies was detected in the villous trophoblast and adventitia tunica around the large blood vessels for all groups. Specific immunostaining for apo D was noted in some mesenchymal and macrophagic-like cells and this signal increased in diabetic placentas. Densitometry analysis of Western blots showed no significant difference for 4-HNE, but was significantly more intense for apo D in diabetic women. The contradictory results for 4-HNE could be due to changes which are too small and are masked in tissue homogenates. The results for apo D showed a strong relationship with GDM in the placenta that may reflect its suggested function in defense mechanisms against oxidative stress.

MMP/ TIMP balance is modulated in vitro by 15dPGJ2 in fetuses and placentas from diabetic rats

Maternal diabetes is associated with morphological placental abnormalities and foeto-placental impairments. These alterations are linked with a dysregulation of the activity of matrix metalloproteinases (MMPs). We investigated the action of 15deoxyDelta(12,14) prostaglandin J(2) (15dPGJ(2)), a natural ligand of the peroxisome proliferator activated receptor (PPAR) gamma, on MMP-2 and MMP-9 activities and tissue inhibitors of matrix metalloproteinases (TIMP) levels in foetuses and placentas from diabetic rats. Diabetes was induced in rat neonates by a single streptozotocin administration (90 mg kg(-1) s.c.). At 13.5 days of gestation, foetal and placental homogenates were prepared for the determination of PPARgamma levels (western blot) and 15dPGJ(2) concentration (enzyme-immunoassay), whereas the in vitro effect of 15dPGJ(2) (2 microM) was evaluated on placental and foetal MMPs and TIMP activities (zymography and reverse zymography), nitrate/nitrite concentrations (Griess method) and thiobarbituric acid reactive substances (TBARS). PPARgamma was increased while 15dPGJ(2) was decreased in placentas and foetuses from diabetic rats. 15dPGJ(2) additions were able to reduce the high activities of MMP-2 and MMP-9 present in diabetic placental tissues. 15dPGJ(2) additions reduced MMP-2 activity in control and diabetic foetuses. TIMP-3 levels were decreased in diabetic placentas and 15dPGJ(2) was able to enhance them to control values. Nitrates/nitrites and TBARS, metabolites of MMPs activators, were increased in the diabetic placenta and reduced by 15dPGJ(2). This study demonstrates that 15dPGJ(2) is a potent modulator of the balance between MMP activities and TIMP levels, which is needed in the correct formation and function of the placenta and foetal organs.

Expression and significance of vascular epithelial growth factor and matrix metalloproteinase-9 and type IV-collagen in gestational diabetic placenta

Objective To investigate the expression and clinical significance of vascular epithelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) and type Ⅳ-collagen(Ⅳ-C) in gestational diabetic placenta. Methods A case-control study was performed in 48 women with gestational diabetes mellitus (GDM) and 36 healthy pregnant women (control), who delivered at Taiyuan Maternal and Infant Health Care Hospital from Jun. 2007 to Dec. 2007. The expressions of VEGF, MMP-9 and Ⅳ-C in placenta were detected by immunohistochemistry. Results The expression of VEGF, MMP-9 and Ⅳ-C in GDM placenta was significantly higher than that of control (70.8% vs 30.6% ,64.6% vs 30.6% ,62.5% vs 27.8%, all P 0.05), however, those GDMs which were poor-controlled, the expression of the three indicators (95.2%, 80.9% and 85.7%) were higher than the control (P<0.05). The expression of MMP-9 was positively correlated with that of VEGF and Ⅳ-C in the GDM group(r=0.579, P<0.01, r=0.596, P<0.01). Conclusions The high expression of VEGF, MMP-9 and Ⅳ-C in GDM placenta may he associated with blood glucose control. Early management of the blood sugar level might alleviate the pathological changes in placenta. Key words: Diabetes, gestational; Placenta; Immunohistochemistry; Vascular endothelial growth factor A; Matrix metalloproteinase 9; Collagen type Ⅳ

The Presence of Kinesin Superfamily Motor Proteins KIFC1 and KIF17 in Normal and Pathological Human Placenta

Kinesin superfamily proteins (KIFs) are motor proteins that participate in chromosomal and spindle movements during mitosis and meiosis, and transport membranous organelles and macromolecules fundamental for cellular functions. Although the roles of KIFs in axonal and dendritic transports have been studied extensively, their role in intracellular transport in general is less well known. The diversity of kinesins suggests that each kinesin may have a specific function. Therefore, in this study we aimed to investigate the presence and cellular localization of KIFC1 and KIF17 in normal and pathological human placentas. First-trimester (22–56 days) and normal, preeclamptic (PE), and diabetic-term placental tissues were obtained and further studied by immunohistochemistry (IHC) and Western blot methods. KIFC1 was mainly localized to the syncytiotrophoblast both in early and term placental samples. However, a stronger immunoreactivity was observed both in PE and diabetic placentas compared to normal-term placentas. KIF17 was most intensively localized in developing vascular endothelium in early pregnancy. Even though KIF17 was moderately stained in the endothelium of villi from normal human-term placentas, stronger immunoreactivity was observed in all types of villi of both PE and diabetic placentas. Western blotting of tissue extracts confirmed the IHC results. Here, we demonstrate the presence of KIFC1 and KIF17 in human placenta for the first time. The intense expression of KIFC1 in syncytiotrophoblast and KIF17 in vascular endothelium suggests that both the proteins might be important in a cargo-transport system. An increased expression pattern of both KIFC1 and KIF17 in PE and diabetes might suggest that these proteins may be involved in complex trophoblast functions and placental pathologies. Further studies will clarify the physiological role of KIFs in human placental transport and development.

Vascular dysfunction in the diabetic placenta: causes and consequences

The development and functioning of the human fetoplacental vascular system are vulnerable to the maternal diabetic milieu. These vessels are in direct continuum with the fetal vascular system and are therefore also vulnerable to fetal endocrine derangements. Increased angiogenesis, altered junctional maturity and molecular occupancy, together with increased leakiness, constitute a well-described phenotype of vessels in the Type 1 diabetic human placenta and can be related to increased levels of placental vascular endothelial growth factor. The causes of these observed changes, whether maternal hyperglycaemia or fetal hyperinsulinaemia, still remain to be shown in the human placenta. Mechanistic studies using different vascular systems have shown high glucose and insulin to have profound vascular effects, with elevations in vascular endothelial growth factor, nitric oxide and protein kinase C being behind alterations in junctional adhesion molecules such as occludin and vascular endothelial-cadherin and vascular leakage of albumin. The role of advanced glycation products and oxidative stress in this vascular pathology is also discussed. The altered molecular mechanisms underlying the vascular changes in the diabetic human placenta may reflect similar consequences of high glucose and hyperinsulinaemia.