Inositol phosphoglycans and preeclampsia: from bench to bedside

A review of the role of inositols in conditions of insulin dysregulation and in uncomplicated and pathological pregnancy

Inositols, a group of 6-carbon polyols, are highly bioactive molecules derived from diet and endogenous synthesis. Inositols and their derivatives are involved in glucose and lipid metabolism and participate in insulin-signaling, with perturbations in inositol processing being associated with conditions involving insulin resistance, dysglycemia and dyslipidemia such as polycystic ovary syndrome and diabetes. Pregnancy is similarly characterized by substantial and complex changes in glycemic and lipidomic regulation as part of maternal adaptation and is also associated with physiological alterations in inositol processing. Disruptions in maternal adaptation are postulated to have a critical pathophysiological role in pregnancy complications such as gestational diabetes and pre-eclampsia. Inositol supplementation has shown promise as an intervention for the alleviation of symptoms in conditions of insulin resistance and for gestational diabetes prevention. However, the mechanisms behind these affects are not fully understood. In this review, we explore the role of inositols in conditions of insulin dysregulation and in pregnancy, and identify priority areas for research. We particularly examine the role and function of inositols within the maternal-placental-fetal axis in both uncomplicated and pathological pregnancies. We also discuss how inositols may mediate maternal-placental-fetal cross-talk, and regulate fetal growth and development, and suggest that inositols play a vital role in promoting healthy pregnancy.

Exploring strengths and limits of urinary D-chiro inositol phosphoglycans (IPG-P) as a screening test for preeclampsia: A systematic review and meta-analysis

Preeclampsia is a severe complication of human pregnancy as it leads to significant maternal and perinatal mortality and morbidity worldwide. A prompt recognition of women that develop this syndrome can improve clinical management, increase surveillance and, finally, improve outcomes. Different methods (based on history, ultrasound, serum and urinary biomarkers) were proposed a screening tests for this disease but their performance showed limited results. Urinary inositol phosphoglycans P-type (IPG-P) were shown to identify in advance most of the women who will develop preeclampsia in case-control and longitudinal studies, so we undertook a systematic review and meta-analysis of published studies. Seven studies met the entry criteria so were evaluated. All case-control studies showed excellent statistical performances in a quality statistical assessment. The meta-analysis considered three longitudinal, prospective studies that showed high sensitivity and specificity with ranges of 0.82- 0.99 and 0.90-1.00, respectively. Univariate measures of accuracy revealed a positive and negative likelihood ratio respectively of 3.61 (95% CI 1.56-5.67) and -2.35 (95% CI -3.79 to -0.91). By univariate approach, we found a pooled logarithm of diagnostic odds ratio of 6.15 (95% CI 2.64-9.67). A limitation of this analysis is that, although conducted in different settings (UK, Italy, France, South Africa, and Mauritius) and different clinical groups, they were based on a single academic group. According to our findings, IPG-P test showed very encouraging results as a rapid noninvasive screening test for preeclampsia. Further studies are needed to verify and to validate the reported findings.

No effects without causes: the Iron Dysregulation and Dormant Microbes hypothesis for chronic, inflammatory diseases

Since the successful conquest of many acute, communicable (infectious) diseases through the use of vaccines and antibiotics, the currently most prevalent diseases are chronic and progressive in nature, and are all accompanied by inflammation. These diseases include neurodegenerative (e.g. Alzheimer's, Parkinson's), vascular (e.g. atherosclerosis, pre-eclampsia, type 2 diabetes) and autoimmune (e.g. rheumatoid arthritis and multiple sclerosis) diseases that may appear to have little in common. In fact they all share significant features, in particular chronic inflammation and its attendant inflammatory cytokines. Such effects do not happen without underlying and initially 'external' causes, and it is of interest to seek these causes. Taking a systems approach, we argue that these causes include (i) stress-induced iron dysregulation, and (ii) its ability to awaken dormant, non-replicating microbes with which the host has become infected. Other external causes may be dietary. Such microbes are capable of shedding small, but functionally significant amounts of highly inflammagenic molecules such as lipopolysaccharide and lipoteichoic acid. Sequelae include significant coagulopathies, not least the recently discovered amyloidogenic clotting of blood, leading to cell death and the release of further inflammagens. The extensive evidence discussed here implies, as was found with ulcers, that almost all chronic, infectious diseases do in fact harbour a microbial component. What differs is simply the microbes and the anatomical location from and at which they exert damage. This analysis offers novel avenues for diagnosis and treatment.

Immunological Tolerance, Pregnancy, and Preeclampsia: The Roles of Semen Microbes and the Father

Although it is widely considered, in many cases, to involve two separable stages (poor placentation followed by oxidative stress/inflammation), the precise originating causes of preeclampsia (PE) remain elusive. We have previously brought together some of the considerable evidence that a (dormant) microbial component is commonly a significant part of its etiology. However, apart from recognizing, consistent with this view, that the many inflammatory markers of PE are also increased in infection, we had little to say about immunity, whether innate or adaptive. In addition, we focused on the gut, oral and female urinary tract microbiomes as the main sources of the infection. We here marshall further evidence for an infectious component in PE, focusing on the immunological tolerance characteristic of pregnancy, and the well-established fact that increased exposure to the father's semen assists this immunological tolerance. As well as these benefits, however, semen is not sterile, microbial tolerance mechanisms may exist, and we also review the evidence that semen may be responsible for inoculating the developing conceptus (and maybe the placenta) with microbes, not all of which are benign. It is suggested that when they are not, this may be a significant cause of PE. A variety of epidemiological and other evidence is entirely consistent with this, not least correlations between semen infection, infertility and PE. Our view also leads to a series of other, testable predictions. Overall, we argue for a significant paternal role in the development of PE through microbial infection of the mother via insemination.

10 workshops on Immunology of preeclampsia

For the 10th issue of the « island workshops », now the Reunion Workshops, organised by Pierre Yves Robillard since the first one in Tahiti challenging the "vascular disease only" theory of pre eclampsia and introducing the primipaternity concept, we examined the reasons for considering an Immunological approach to the disease. This (brief) overview thus examines several important topics in an Immunological framework. I have chosen to present here the evolution of the main themes rather than a purely chronological vision.

Endothelial dysfunction and metabolic syndrome in preeclampsia: an alternative viewpoint

Several clinical and basic science reports have elucidated partial aspects of the pathophysiology of preeclampsia and have led many authors to conclude that different "subtypes" of the disease exist. All these subtypes share the main clinical features of the disease and present additional characteristics that define different clinical phenotypes. Nevertheless, immunological alterations, endothelial dysfunction, and insulin resistance constantly characterize this syndrome. These aspects are intimately related at a molecular level; thus, we propose an alternative approach to explaining biologically the main intracellular processes that occur in preeclampsia and this may yield an insight into the pathogenesis.

Urinary inositol phosphoglycan-P type: near patient test to detect preeclampsia prior to clinical onset of the disease. A study on 416 pregnant Mauritian women

Preeclampsia and eclampsia account for major pregnancy complications in Mauritius, an emerging country (maternal mortality rate of 60 per 100,000 deliveries). This prospective longitudinal study was carried out in the main regional hospital in the north of the island, to measure inositol phosphoglycan-P type (IPG-P) in the urine of pregnant women (using an ELISA-based assay). Women had approximately 10 prenatal visits per pregnancy and a complete follow-up in this same referral centre after the first trimester of pregnancy. Urine samples were collected every 1-4 weeks in all women. In a cohort of 416 patients, preeclampsia (PE) was diagnosed in 34 women. In established PE (hypertension and proteinuria), the assay as a diagnostic test showed a positive likelihood ratio of 18.73, a negligible negative likelihood ratio with area under the curve (AUC) of 0.99, sensitivity of 96.7%, specificity of 94.8% and remained negative in control women (n=312), women with gestational hypertension (without proteinuria (n=56), and gestational diabetic mothers (n=14). Moreover, as a predictive screening test two weeks before the diagnosis of PE, the assay showed sensitivity of 84.2% and specificity of 83.6%. Detection of urinary inositol phosphoglycan-P type in pregnant women can be a useful confirmatory marker of PE, as well as a predictive marker, two weeks before the onset of the disease.