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Being born small for gestational age (SGA) confers increased risks of perinatal morbidity and mortality and increases the risk of cardiovascular complications and diabetes in later life. Accumulating evidence suggests that the etiology of SGA is usually associated with poor placental vascular development in early pregnancy. We examined metabolomic profiles using ultra performance liquid chromatographyÀmass spectrometry (UPLCÀMS) in three independent studies: (a) venous cord plasma from normal and SGA babies, (b) plasma from a rat model of placental insufficiency and controls, and (c) early pregnancy peripheral plasma samples from women who subsequently delivered a SGA baby and controls. Multivariate analysis by cross-validated Partial Least Squares Discriminant Analysis (PLS-DA) of all 3 studies showed a comprehensive and similar disruption of plasma metabolism. A multivariate predictive model combining 19 metabolites produced by a Genetic Algorithm-based search program gave an Odds Ratio for developing SGA of 44, with an area under the Receiver Operator Characteristic curve of 0.9. Sphingolipids, phospholipids, carnitines, and fatty acids were among this panel of metabolites. The finding of a consistent discriminatory metabolite signature in early pregnancy plasma preceding the onset of SGA offers insight into disease pathogenesis and offers the promise of a robust presymptomatic screening test.

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In this review the authors intend to demonstrate the need for supplementing conventional repair of the injured nerve with alternative therapies, namely transplantation of stem or progenitor cells. Although peripheral nerves do exhibit the potential to regenerate axons and reinnervate the end organ, outcome following severe nerve injury, even after repair, remains relatively poor. This is likely because of the extensive injury zone that prevents axon outgrowth. Even if outgrowth does occur, a relatively slow growth rate of regeneration results in prolonged denervation of the distal nerve. Whereas denervated Schwann cells (SCs) are key players in the early regenerative success of peripheral nerves, protracted loss of axonal contact renders Schwann cells unreceptive for axonal regeneration. Given that denervated Schwann cells appear to become effete, one logical approach is to support the distal denervated nerve environment by replacing host cells with those derived exogenously. A number of different sources of stem/precursor cells are being explored for their potential application in the scenario of peripheral nerve injury. The most promising candidate, transplant cells are derived from easily accessible sources such as the skin, bone marrow, or adipose tissue, all of which have demonstrated the capacity to differentiate into Schwann cell–like cells. Although recent studies have shown that stem cells can act as promising and beneficial adjuncts to nerve repair, considerable optimization of these therapies will be required for their potential to be realized in a clinical setting. The authors investigate the relevance of the delivery method (both the number and differentiation state of cells) on experimental outcomes, and seek to clarify whether stem cells must survive and differentiate in the injured nerve to convey a therapeutic effect. As our laboratory uses skin-derived precursor cells (SKPCs) in various nerve injury paradigms, we relate our findings on cell fate to other published studies to demonstrate the need to quantify stem cell survival and differentiation for future studies.

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Abstract-Preeclampsia, a major cause of maternal and perinatal mortality and morbidity, is thought to be attributed, in part, to impaired trophoblast invasion. Peroxisome proliferator-activated receptors are ligand-activated transcription factors expressed in trophoblasts, which regulate the expression of a number of genes involved in cell differentiation and proliferation. We investigated the effect of the administration of a peroxisome proliferator-activated receptor-␥ antagonist during uncomplicated pregnancy in rats. Using an intraperitoneal miniosmotic pump, healthy pregnant rats were administered either vehicle or the peroxisome proliferator-activated receptor-␥-specific antagonist, T0070907 (1 mg/kg per day from gestational days 11-15). Rats treated with T0070907 developed key features of preeclampsia, including elevated mean arterial blood pressure, proteinuria, endothelial dysfunction, reduced pup weight, and increased platelet aggregation. T0070907-treated rats had reduced plasma vascular endothelial growth factor and increased plasma soluble fms-like tyrosine kinase 1. Furthermore, increases in total placental soluble fms-like tyrosine kinase 1 mRNA and fms-like tyrosine kinase 1 protein were also demonstrated, suggesting the placenta as the main contributor to the increased circulating levels of soluble fms-like tyrosine kinase 1. The labyrinthine trophoblast in the placentas of T0070907-treated rats were less differentiated, had increased cellular proliferation, and were strongly immunopositive for CD-31 staining, indicating adaptive angiogenesis. The present study suggests that peroxisome proliferator-activated receptor-␥ may play a pivotal role in the progression of a healthy pregnancy and may critically regulate the risk of preeclampsia. These findings have important implications regarding the underlying etiology of preeclampsia and potential therapeutic targets. (Hypertension. 2011;58:882-887.) • Online Data Supplement Key Words: peroxisome proliferator activated receptor-␥ Ⅲ T0070907 Ⅲ preeclampsia Ⅲ vascular dysfunction P reeclampsia is a major cause of maternal and perinatal mortality and morbidity worldwide causing Ϸ15% of all direct maternal deaths and mediating a 5-fold increase in perinatal mortality. 1 Although the underlying etiology of preeclampsia is poorly understood, this condition is characterized by a relatively hypoperfused placenta, which stimulates the maternal response manifesting as hypertension, vascular dysfunction, and a pro-oxidant state. 2 Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors that regulate the expression of a number of genes involved in cell differentiation and proliferation. 3 PPAR-␥ plays a predominant role in normal vascular function 4,5 and in the differentiation of labyrinthine trophoblast lineages, 6 which, along with the fetal endothelium, form the vascular exchange interface with maternal blood. 7 Homozygous PPAR-␥-deficient embryos die because of placental dysfunction, 8 and PPAR-␥ null placentas develo...

Abstract-Preeclampsia is a multisystemic disorder of pregnancy characterized by hypertension, proteinuria, and maternal endothelial dysfunction. It is a major cause of maternal and perinatal morbidity and mortality and is thought to be attributable, in part, to inadequate trophoblast invasion. Peroxisome proliferator-activated receptor-␥ (PPAR-␥) is a ligand-activated transcription factor expressed in trophoblasts, and the vasculature of which activation has been shown to improve endothelium-dependent vasodilatation in hypertensive conditions. We investigated the effects of the administration of a PPAR-␥ agonist using the reduced uterine perfusion pressure (RUPP) rat model of preeclampsia. The selective PPAR-␥ agonist, rosiglitazone, was administered to pregnant rats that had undergone RUPP surgery. To investigate whether any observed beneficial effects of PPAR-␥ activation were mediated by the antioxidant enzyme, heme oxygenase 1, rosiglitazone was administered in combination with the heme oxygenase 1 inhibitor tinprotoporphyrin IX. RUPP rats were characterized by hypertension, endothelial dysfunction, and elevated microalbumin:creatinine ratios. Rosiglitazone administration ameliorated hypertension, improved vascular function, and reduced the elevated microalbumin:creatinine ratio in RUPP rats. With the exception of microalbumin:creatinine ratio, these beneficial effects were abrogated in the presence of the heme oxygenase 1 inhibitor. Administration of a PPAR-␥ agonist prevented the development of several of the pathophysiological characteristics associated with the RUPP model of preeclampsia, via a heme oxygenase 1-dependent pathway. The findings from this study provide further insight into the underlying etiology of preeclampsia and a potential therapeutic target for the treatment of preeclampsia. (Hypertension. 2011;58:280-286.) • Online Data SupplementKey Words: peroxisome proliferator-activated receptor-␥ Ⅲ preeclampsia Ⅲ reduced uterine perfusion pressure Ⅲ hypertension Ⅲ heme oxygenase 1 Ⅲ vascular dysfunction P reeclampsia is a major cause of maternal and perinatal morbidity and mortality worldwide, causing Ϸ15% of all direct maternal deaths and mediating a 5-fold increase in perinatal mortality. 1 Although the underlying etiology of preeclampsia is poorly understood, it is characterized by a relatively hypoperfused placenta, which stimulates the maternal response manifesting as hypertension, vascular dysfunction, alterations in platelet aggregation, and a pro-oxidant state. 2 There is currently no effective pharmacological intervention available for the treatment of preeclampsia, and, consequently, pregnancies are often delivered preterm for maternal benefit, imposing the challenges of iatrogenic prematurity on the fetus. 3 Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors that regulate the expression of a number of genes involved in cell differentiation and proliferation. 4 PPAR-␥ plays a predominant role in normal vascular function 5 and in the differ...

Background and purpose: Cannabidiol (CBD) is a phytocannabinoid, with anti-apoptotic, anti-inflammatory and antioxidant effects and has recently been shown to exert a tissue sparing effect during chronic myocardial ischaemia and reperfusion (I/R). However, it is not known whether CBD is cardioprotective in the acute phase of I/R injury and the present studies tested this hypothesis. Experimental approach: Male Sprague-Dawley rats received either vehicle or CBD (10 or 50 mg·kg -1 i.v.) 10 min before 30 min coronary artery occlusion or CBD (50 mg·kg -1 i.v.) 10 min before reperfusion (2 h). The appearance of ventricular arrhythmias during the ischaemic and immediate post-reperfusion periods were recorded and the hearts excised for infarct size determination and assessment of mast cell degranulation. Arterial blood was withdrawn at the end of the reperfusion period to assess platelet aggregation in response to collagen. Key results: CBD reduced both the total number of ischaemia-induced arrhythmias and infarct size when administered prior to ischaemia, an effect that was dose-dependent. Infarct size was also reduced when CBD was given prior to reperfusion. CBD (50 mg·kg -1 i.v.) given prior to ischaemia, but not at reperfusion, attenuated collagen-induced platelet aggregation compared with control, but had no effect on ischaemia-induced mast cell degranulation. Conclusions and implications:This study demonstrates that CBD is cardioprotective in the acute phase of I/R by both reducing ventricular arrhythmias and attenuating infarct size. The anti-arrhythmic effect, but not the tissue sparing effect, may be mediated through an inhibitory effect on platelet activation. British Journal of Pharmacology