Maternal serum omentin-1 profile is similar in humans and in the rat animal model

Adipokines in pregnancy

Reproductive success consists of a sequential events chronology, starting with the ovum fertilization, implantation of the embryo, placentation, and cellular processes like proliferation, apoptosis, angiogenesis, endocrinology, or metabolic changes, which taken together finally conduct the birth of healthy offspring. Currently, many factors are known that affect the regulation and proper maintenance of pregnancy in humans, domestic animals, or rodents. Among the determinants of reproductive success should be distinguished: the maternal microenvironment, genes, and proteins as well as numerous pregnancy hormones that regulate the most important processes and ensure organism homeostasis. It is well known that white adipose tissue, as the largest endocrine gland in our body, participates in the synthesis and secretion of numerous hormones belonging to the adipokine family, which also may regulate the course of pregnancy. Unfortunately, overweight and obesity lead to the expansion of adipose tissue in the body, and its excess in both women and animals contributes to changes in the synthesis and release of adipokines, which in turn translates into dramatic changes during pregnancy, including those taking place in the organ that is crucial for the proper progress of pregnancy, i.e. the placenta. In this chapter, we are summarizing the current knowledge about levels of adipokines and their role in the placenta, taking into account the physiological and pathological conditions of pregnancy, e.g. gestational diabetes mellitus, preeclampsia, or intrauterine growth restriction in humans, domestic animals, and rodents.

Novel Biomolecules in the Pathogenesis of Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is one of the most common metabolic diseases in pregnant women. Its early diagnosis seems to have a significant impact on the developing fetus, the course of delivery, and the neonatal period. It may also affect the later stages of child development and subsequent complications in the mother. Therefore, the crux of the matter is to find a biopredictor capable of singling out women at risk of developing GDM as early as the very start of pregnancy. Apart from the well-known molecules with a proven and clear-cut role in the pathogenesis of GDM, e.g., adiponectin and leptin, a potential role of newer biomolecules is also emphasized. Less popular and less known factors with different mechanisms of action include: galectins, growth differentiation factor-15, chemerin, omentin-1, osteocalcin, resistin, visfatin, vaspin, irisin, apelin, fatty acid-binding protein 4 (FABP4), fibroblast growth factor 21, and lipocalin-2. The aim of this review is to present the potential and significance of these 13 less known biomolecules in the pathogenesis of GDM. It seems that high levels of FABP4, low levels of irisin, and high levels of under-carboxylated osteocalcin in the serum of pregnant women can be used as predictive markers in the diagnosis of GDM. Hopefully, future clinical trials will be able to determine which biomolecules have the most potential to predict GDM.

The role of adipokines in the pathogenesis of gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is a complex condition whose physiopathology to date has not been completely clarified. Two major metabolic disorders, insulin resistance and β-cells dysfunction, play currently major role in pathogenesis of GDM. These elements are influenced by the amount of adipose tissue present before and/or during the pregnancy. Consequently, adipokines (adiponectin (APN), leptin (LPT), adipocyte fatty acid-binding protein, resistin, visfatin, omentin, vaspin, apelin, chemerin) secreted by adipose tissue, may contribute directly and/or indirectly, through the enhancement of chronic inflammation, aggravating insulin resistance and promoting GDM onset. This review aims to outline the potential physiopathological and prognostic role in GDM of adipokines, mainly APN and LPT.

The role of adipokines in developmental programming: evidence from animal models

Alterations in the environment during critical periods of development, including altered maternal nutrition, can increase the risk for the development of a range of metabolic, cardiovascular and reproductive disorders in offspring in adult life. Following the original epidemiological observations of David Barker that linked perturbed fetal growth to adult disease, a wide range of experimental animal models have provided empirical support for the developmental programming hypothesis. Although the mechanisms remain poorly defined, adipose tissue has been highlighted as playing a key role in the development of many disorders that manifest in later life. In particular, adipokines, including leptin and adiponectin, primarily secreted by adipose tissue, have now been shown to be important mediators of processes underpinning several phenotypic features associated with developmental programming including obesity, insulin sensitivity and reproductive disorders. Moreover, manipulation of adipokines in early life has provided for potential strategies to ameliorate or reverse the adverse sequalae that are associated with aberrant programming and provided insight into some of the mechanisms involved in the development of chronic disease across the lifecourse.

Adiponectin and Omentin Levels as Predictive Biomarkers of Preterm Birth in Patients with Gestational Diabetes Mellitus

Objective

The aim of this study was to determine any changes in adiponectin and omentin levels in GDM patients who delivered at term and preterm and to evaluate whether adipokines can be useful as a clinical biomarker to predict subsequent preterm delivery.

Patients and Methods

The levels of adiponectin and omentin were measured in four groups: (1) women with GDM who delivered at term (n=63); (2) women with GDM who had the symptoms of threatened preterm labor and delivered at term (n=23); (3) women with GDM and spontaneous preterm birth (before 37 completed weeks of gestation) (n=19); (4) women with physiological pregnancy (n=55).

Results

In comparison with control group the median adiponectin concentrations were significantly lower in all GDM groups (10737 versus 8879; 7057; 6253 ng/ml, respectively; p<0.01). The median omentin concentrations were also significantly lower in all GDM groups in comparison with control group (469 versus 432; 357; 308 ng/ml, respectively; p<0.01). No significant differences in adiponectin and omentin levels between the GDM, preterm labor, and preterm birth groups were observed. However, there was a trend towards lower adiponectin and omentin levels in preterm birth group. The strong correlations between adiponectin and omentin levels were observed in all groups (R=0.801, p<0.001; R=0.824, p<0.001; R=0.705, p<0.001; R=0.764, respectively; p<0.001). In the univariable logistic regression model, significant correlation between omentin concentrations and preterm birth occurrence was found.

Conclusions

Our findings suggest that omentin-1, rather than adiponectin, could be useful as a predictor of preterm birth in patients with gestational diabetes mellitus.

Trigonelline Inhibits Inflammation and Protects β Cells to Prevent Fetal Growth Restriction during Pregnancy in a Mouse Model of Diabetes

Background: As an active component from traditional Chinese medicine, trigonelline has a protective effect on diabetes. This study evaluated the protective effects of trigonelline on diabetic mice during pregnancy. Methods: Diabetes was induced in female mice by intraperitoneal injection for continuous 5-day of 40 mg/kg/day streptozotocin. Female mice were divided into 4 groups after they were allowed to mate with normal male mice: nondiabetic, nondiabetic treated with trigonelline (70 mg/kg) for 18 days, diabetic, and diabetic treated with trigonelline (70 mg/kg). Results: Diabetic pregnant mice had significantly higher levels of blood glucose, serum total cholesterol, triglyceride, insulin, and leptin but lower serum omentin-1 level and insulin sensitivity index than the nondiabetic ones. Trigonelline improved the hyperglycemia, dyslipidemia, insulin resistance, and adipocytokine of diabetic pregnant mice. Diabetic pregnant mice had significantly reduced fetus numbers, fetal weight, and fetal/placental ratio, which were reversed by trigonelline. Trigonelline prevented the increase in proinflammatory cytokines and reduced interleukin-10 level in placenta of diabetic pregnant mice. Trigonelline increased β-cell replication and the decreased β-cell mass, and decreased the β-cell apoptosis of diabetic pregnant mice. Conclusion: These findings suggest that trigonelline protects diabetic pregnancy partly by suppressing inflammation, regulating the secretion of adipocytokines, increasing β-cell mass, replication, and decreasing β-cell apoptosis.

Comparison of maternal omentin-1 levels and genetic variability between spontaneous term and preterm births

OBJECTIVE

To determine maternal omentin-1 levels and genetic variability in the omentin-1 gene in women with spontaneous term and preterm births (PTBs).

MATERIALS AND METHODS

Maternal serum omentin-1 levels and the role of the omentin-1 Val109Asp (rs2274907) polymorphism were evaluated in 32 women with spontaneous term birth (sTB) and 30 women with spontaneous preterm birth (sPTB) including women with (n = 16) and without (n = 14) preterm premature rupture of membranes (PPROM).

RESULTS

Maternal omentin-1 levels were significantly lower in women with sPTBs compared to term births during the hospitalization period (p = .015). However, maternal omentin-1 levels were similar in women with sPTBs with and without PPROM (p = .990). Furthermore, the omentin-1 Val109Asp polymorphism was found to have no significant effect on omentin-1 serum levels. In addition, no significant differences in genotype distributions and allelic frequencies between sTB and sPTB were established.

CONCLUSIONS

High omentin-1 levels in normal sTBs compared to PTBs without significant differences between cases with and without PPROM suggest that omentin-1 plays a potential role in the pathophysiology of PTB but not in the PPROM mechanism itself.