Current Pharmaceutical Biotechnology - Volume 15, Issue 1, 2014

Metabolic diseases induced by metabolic syndrome (MS) have been increased during the past two decades. During healthy pregnancy maternal organs and placenta are challenged to adapt to the increasingly physiological changes. In addition to the increasingly proatherogenic MS, pregnant woman develops a high cardiac output, hypercoagulability, increased inflammatory activity and insulin resistance with dyslipidemia. The MS describes a cluster of metabolic changes associated with an impact on the physiology of many organs. While the metabolic syndrome is directly responsible for the development of atherosclerotic cardiovascular disease, additional impact on human pregnancy like preterm delivery with low-birth-weight infants as well as the development of diseases such as diabetes, preeclampsia and hypertension. Recent evidence suggests that MS is originated in fetal life in association with maternal nutrition during pregnancy and fetal programming which apparently increases the susceptibility for MS in children and later life. This review will describe the MS in association with the origin of the emerging diseases during pregnancy such as diabetes, preeclampsia and others. The influence of perinatal environment and maternal diet and smoking on MS as well as the genetic biomarkers of MS will be described.

Currently, it is well-known that changes in the maternal metabolic status induce changes in the intrauterine environment and modify the metabolic status of the fetuses, playing a key role in the growth, life-time fitness/obesity and probability of appearance of metabolic disorders in the offspring. There is increasing evidence that these effects may not be only limited to the first generation of descendants, the offspring directly exposed to metabolic challenges, but to subsequent generations either exposed (multigenerational exposure) or unexposed (intergenerational or transgenerational inheritance) to such metabolic defies, perpetuating the problem. Thus, having in mind the impact on worldwide public health, the present review outlines, based on results of translational animal research and clinical human studies, the mechanisms, pathways and practical implications involved in the transgenerational inheritance of the metabolic syndrome.

More glucose crosses the placenta than any other substrate, but correlations between its concentration in maternal plasma and fetal growth are not found consistently. The accumulation of maternal fat depots and hyperlipidemia are the two principal changes in lipid metabolism during pregnancy. Although lipids cross the placenta with difficulty, maternal plasma triacylglycerols (TAG) and non-esterified fatty acids (NEFA) correlate with fetal lipids, fetal growth and fat mass under certain conditions. In intrauterine growth restriction, impaired placental transfer of lipophilic compounds (long-chain polyunsaturated fatty acids and lipophilic vitamins) seems to underpin metabolic dysfunction and decreased birth weight. In gestational diabetes mellitus (GDM), maternal TAG and NEFA levels correlate with neonatal anthropometric measures. In GDM, adipocyte fatty acid-binding protein in fetuses correlated with neonatal fat mass; changes in maternal or cord blood leptin, retinol binding protein 4 and adiponectin concentrations have been related to neonatal fat mass or birth weight, although their importance remains to be investigated. The angiopoietin-like protein 4 (ANGPTL-4) is secreted from adipose tissue, liver and placenta, and irreversibly inhibits lipoprotein lipase (LPL) activity. Maternal plasma ANGPTL-4 is decreased in GDM, and it has been proposed to be responsible for an increase in placental LPL activity, which would facilitate a greater fatty acid placental transfer, contributing to the higher fetal fat accumulation. Thus, while evidence suggesting major involvement of maternal lipid metabolism in fetal adiposity and growth exists, the precise mechanisms remain to be elucidated.

Gestational diabetes mellitus is one of the most often medical conditions during pregnancy affecting 5-6% of all pregnancies. The etiology of gestational diabetes is not clearly understood. In obesity and diabetes mellitus type 2, abnormal insulin signaling is an important agent mediating the increase of insulin resistance. Insulin receptor substrate serine phosphorylation is a time-controlled physiological reaction in insulin signaling that has been disrupted by metabolic and inflammatory stresses to support insulin resistance. Several kinases, including inhibitor of nuclear factor ĸB kinase β (IKK β), c-Jun N-terminal kinase (JNK), mammalian target of rapamycin (mTOR), protein kinase C (PKC) and ribosomal S6 protein kinase (S6K), are activated by these stimulators of insulin resistance and phosphorylate insulin receptor substrate proteins on several serine residues in an uncontrollable method. There are an increasing number of data indicating that substance P, being one of the crucial activators of these kinases, is a potent cytokine that impairs insulin signaling. Here we discuss recent studies that expand our understanding of how substance P may contribute to the development of insulin resistance. In our opinion, there are many interesting data suggesting that substance P may be a new player in the pathogenesis of this unfavorable condition, leading not only to the development of diabetes mellitus type 2, but also gestational diabetes. Since the etiology of gestational diabetes remains unclear, there is a strong need to explore new directions, including those not directly associated with the canonical knowledge regarding this pathology.

Gestational diabetes mellitus (GDM) represents a condition of glucose intolerance with first appearance or recognition at the time of a pregnancy, associated with an inadequate pancreatic response to the advanced insulin resistance of the later stages of pregnancy, and accompanied by enhancing β-cell mass and secretion of insulin. Women who had GDM exhibit a higher risk for later advent of type 2 diabetes mellitus (T2DM) and cardiovascular diseases (CVD). Additionally, previous GDM has been proposed as independently correlated with higher risk for development of atherosclerosis in a healthy population, similar to the metabolic syndrome (MetS) and independently of the presence of established CVD risk factors. Available data indicate multiple metabolic abnormalities common in women with GDM, including a high small dense low-density lipoprotein (sdLDL) concentration and a resultant high prevalence of CVD and the MetS. Preliminary data indicate that a measurement of sdLDL is worthwhile in women with GDM during pregnancy as well as the postpartum period. A close follow up of these women should be emphasized in clinical practice because GDM could predict not only eventual health risks for these mothers, but also their offspring. Thus, an improvement in care and risk modification of women with GDM may not only contribute towards improved CVD profile, but also potentially prevent adverse outcomes in their offspring. Lifestyle changes should be promoted in order to prevent excessive weight gain during pregnancy and decrease the risk of MetS in the postpartum and long-term.

Pregnancy is a specific state of heightened coagulability related to the increase in procoagulant agents and to the reduced fibrinolysis. Pregnancy is associated with a 4-fold increased risk of developing venous thromboembolism (VTE) and this risk still increases to 14-fold during puerperium. A correlation between the metabolic syndrome and development of cardiovascular events and cerebrovascular incidents has been described. Such a relationship is referred to a hypercoagulable state due to increased serum levels of the plasminogen activator inhibitor-1 (PAI-1), fibrinogen, factor (F) VII and VIII, von Willebrand factor and from endothelial activation, caused by increased circulating adhesion molecules. As to the risk of VTE, the probability for its association with cardiovascular incidents is increased by common underlying mechanisms such as the activation of platelets and the blood coagulation. A correlation between idiopathic VTE and the metabolic syndrome has been reported. The anticoagulant therapy may be recommended during the pregnancy for the treatment or the prophylaxis of VTE and, in women with artificial heart valves, for the prevention of the valve thrombosis and systemic embolisation. There are also specific conditions during pregnancy which benefit from anticoagulant use, such as recurrent fetal loss, thrombophilia and assisted reproductive technology. There are no published specific data about using of anticoagulant agents in pregnant patients with the metabolic syndrome except for a few articles addressing reproductive problems. The mechanisms of anticoagulant action were studied with the focus on heparinoids, because of their safety not only for the patient but also for the fetus. The new oral anticoagulants were also shortly described although they have been contraindicated during the pregnancy.

Objective: Hypertensive disorders in pregnancy remain a major cause of maternal morbidity and mortality. Blood pressure control is essential for maternal and neonatal outcome. Therefore, we analyzed the potency and side effects of two treatment options (nicardipine compared to labetalol) in order to gain insight in improved treatment of severe hypertension during pregnancy and to evaluate the feasibility of a randomised controlled trial. Study design: A nested case control study in an inner city teaching hospital alongside a meta-analysis. Data from women who received nicardipine were compared with patients who received labetalol during pregnancy. Primary outcome measure was successful control of severe hypertension. Secondary outcome measures were maternal and neonatal side effects. These results were included in a meta-analysis. Results: Only one previous study described nicardipine in comparison to labetalol during pregnancy. The combined results indicate a similar success-rate of treatment with nicardipine compared to labetalol during pregnancy. Women treated with nicardipine had more often tachycardia, headache and nausea compared to women treated with labetalol. Hypotension resulting in fetal distress was found more often in the labetalol group. Conclusion: Nicardipine is a potent drug to control hypertension during pregnancy with side effects including maternal headaches, nausea and tachycardia. Labetalol had more neonatal side effects including hypotension compared with nicardipine. These results support the justification and prove that it is safe to perform a randomized controlled trial comparing nicardipine to labetalol in the treatment of severe hypertension in pregnancy.

Metformin, an insulin-sensitizing drug commonly used to treat Type 2 Diabetes Mellitus (T2DM), has been increasingly used off-label for the treatment of polycystic ovary syndrome (PCOS), which affects at least 5-10% of reproductive- age women. With very little risk associated with its use, metformin provides many important benefits to women with PCOS, including regulating menstrual cycles, improving clinical signs of hyperandrogenism, ameliorating metabolic syndrome, inducing ovulation, improving pregnancy rates and pregnancy outcomes, preventing gestational diabetes, and preventing progression to T2DM. Here, we review the indications for metformin in women with PCOS, with a focus on the use of metformin during pre-conception and pregnancy.

This review presents available evidence for possible application of n-3 long chain polyunsaturated fatty acids (PUFAs) in pregnant obese women with metabolic syndrome (MS) and focuses on prophylaxis of pregnancy complications associated with MS such as gestational hypertension, preeclampsia and gestational diabetes. Dietary supplementation with n-3 PUFAs has recently become popular and their adequate intake during pregnancy and early childhood is of clinical importance. The results of experimental and epidemiological investigations reveal that n-3 PUFAs, especially α- linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), may decrease the risk of cardiovascular diseases. It is believed that n-3 PUFAs affect a multitude of molecular pathways, involving regulation of gene expression, alteration of physical and chemical properties of cellular membranes and modulation of membrane channels and proteins. A large body of evidence focuses on anti-inflammatory properties of PUFAs which seem to be fundamental in prevention and reversing of insulin resistance, atherogenic dyslipidemia, hypertension, thromboembolism and in improving vascular function. Despite the potential PUFAs benefits of decreasing insulin resistance, their application in order to prevent preeclampsia, gestational hypertension and gestational diabetes mellitus in pregnant women with MS has not yet been established. Numerous reports have revealed that appropriate fetal development, including neuronal, retinal and immune function depends on EPA and DHA which are crucial also for prevention of preterm birth. Thus the supplementation with EPA and DHA is highly recommended during pregnancy although the optimal dosing and treatment strategies still need to be determined.

The clinical recognition and adequate treatment of women with hyperglycemia during pregnancy is significant in order to reduce neonatal complications correlated with gestational diabetes mellitus (GDM). The traditional management of pregnant patients with GDM in whom diet restriction is not sufficient enough involves subcutaneous insulin administration. However, insulin therapy has several disadvantages. It is therefore highly desirable to find an effective alternative to insulin. Glyburide (also known as glibenclamide) is currently classified as Category C by the U.S. Food and Drug Administration (FDA) for use in pregnancy. Despite the fact that the FDA does not approve glyburide for the treatment of GDM, the American College of Obstetricians and Gynecologists (ACOG) recommended in 2013 that: “when pharmacologic treatment of GDM is indicated, insulin and oral medications are equivalent in efficacy, and either can be an appropriate first-line therapy”. These conflicting standpoints result from published contradictory data concerning the risks and benefits of the use of glyburide for the treatment of women with GDM. In this focused review we first present the current state of knowledge about the pharmacokinetics and pharmacodynamics of glyburide, including aspects of the transplacental transport and placental metabolism of the drug, and then we comment on several clinical studies describing the use of glyburide for the treatment of women with GDM. Since the contradictory data primarily concern the transfer of glyburide across the placenta, further rigorous scientific researches focusing on this issue are required in order to develop evidence-based recommendations for the use of glyburide for the treatment of women with GDM.