Comparison of serum maternal adiponectin concentrations in women with isolated intrauterine growth retardation and intrauterine growth retardation concomitant with pre-eclampsia

The role of serum adipokine levels in preeclampsia: A systematic review

BACKGROUND

Preeclampsia represents a major pregnancy complication, associated with high rates of perinatal morbidity. The aim of this systematic review is to accumulate current literature evidence in order to examine the pattern of serum adipokine levels among preeclamptic women and asses their potential efficacy in the prediction of the disease.

METHODS

Medline, Scopus, CENTRAL, Clinicaltrials.gov and Google Scholar databases were systematically searched from inception. All observational studies reporting serum adipokine values among preeclamptic and healthy pregnant women were held eligible.

RESULTS

A total of 163 studies were included, comprising 23,482 women. Leptin was evaluated in 91 studies and its values were found to be significantly elevated in preeclamptic women during all pregnancy trimester, independently of disease onset and severity. Preeclampsia was also associated with increased serum fatty acid binding protein-4 and chemerin levels, when measured both during the 1st and 3rd trimester. Data concerning the rest adipokines were either conflicting or limited to reach firm conclusions. Quality of evidence was evaluated to be high for leptin, moderate for serum fatty acid binding protein-4 and chemerin and low for the other adipokines.

CONCLUSIONS

The existing evidence suggests that preeclampsia is linked to increased levels of leptin, chemerin and fatty acid binding protein-4 in all pregnancy trimesters and forms of the disease. Inconsistent data currently exists concerning the role of the other adipokines. Large-scale prospective studies should longitudinally evaluate the serum concentration of novel adipokines and define the optimal threshold and timing of measurement to be widely applied in clinical practice.

Mechanisms of Adiponectin Action in Fertility: An Overview from Gametogenesis to Gestation in Humans and Animal Models in Normal and Pathological Conditions

Adiponectin is the most abundant plasma adipokine. It mainly derives from white adipose tissue and plays a key role in the control of energy metabolism thanks to its insulin-sensitising, anti-inflammatory, and antiatherogenic properties. In vitro and in vivo evidence shows that adiponectin could also be one of the hormones controlling the interaction between energy balance and fertility in several species, including humans. Indeed, its two receptors—AdipoR1 and AdipoR2—are expressed in hypothalamic–pituitary–gonadal axis and their activation regulates Kiss, GnRH and gonadotropin expression and/or secretion. In male gonads, adiponectin modulates several functions of both somatic and germ cells, such as steroidogenesis, proliferation, apoptosis, and oxidative stress. In females, it controls steroidogenesis of ovarian granulosa and theca cells, oocyte maturation, and embryo development. Adiponectin receptors were also found in placental and endometrial cells, suggesting that this adipokine might play a crucial role in embryo implantation, trophoblast invasion and foetal growth. The aim of this review is to characterise adiponectin expression and its mechanism of action in male and female reproductive tract. Further, since features of metabolic syndrome are associated with some reproductive diseases, such as polycystic ovary syndrome, gestational diabetes mellitus, preeclampsia, endometriosis, foetal growth restriction and ovarian and endometrial cancers, evidence regarding the emerging role of adiponectin in these disorders is also discussed.

Adiponectin Participates in Preeclampsia by Regulating the Biological Function of Placental Trophoblasts through P38 MAPK-STAT5 Pathway

BACKGROUND

We aimed to investigate the participation of adiponectin in preeclampsia, and to explore the possible mechanism.

METHODS

A total of 52 patients with preeclampsia and 30 normal women with full-term pregnancy were enrolled. Immunohistochemistry was used to detect the localization of MAPK and STAT5. RT-PCR was used to detect the expression of adiponectin mRNA in placental tissue of patients with preeclampsia and normal pregnant women. Western blot was used to detect the expression of adiponectin protein, MAPK, p-MAPK, STAT5 and p-STAT5 in placental tissue of patients with preeclampsia and normal pregnant women.

RESULTS

p-p38 was highly expressed in placental trophoblasts of patients with preeclampsia, while p-STAT5 was less expressed. Expression level of p-p38 and p-STAT5 in patients with preeclampsia were significantly different from those in normal pregnant women (P<0.01). Expression level of adiponectin mRNA was significantly lower in patients with preeclampsia than in normal pregnant women (P<0.05). Level of p-p38 expression was negatively correlated with levels of adiponectin expression (r=-0.413, P<0.05). Expression level of p-STAT5 was positively correlated with expression level of adiponectin (r=0.526, P<0.01).

CONCLUSION

Adiponectin participates in preeclampsia by regulating the biological function of placental tropho-blasts through p38 MAPK-STAT5 pathway.

Maternal and Cord Blood Adiponectin Concentrations in Small for Gestational Age: A Meta-Analysis

Background: Adiponectin, which may have a growth-promoting effect through its insulin-sensitizing action, is thought to play a key role in fetal growth. This study was performed to determine whether maternal and/or cord blood adiponectin concentrations differ between small for gestational age (SGA) and healthy controls. Methods: Databases were searched to identify good quality English language studies providing the number of SGA and healthy controls, and the means and standard deviations of maternal or cord blood adiponectin concentration in both groups. A meta-analysis was performed to summarize the standardized mean differences (SMDs) in maternal and cord blood adiponectin concentrations between SGA and healthy controls. Results: There was no statistically significant difference in maternal blood adiponectin concentration between SGA and healthy controls (n = 8, p = 0.951). However, cord blood adiponectin concentration was significantly lower in SGA than in healthy controls (n = 6, p = 0.028), and the effect was large (i.e., SMD >0.7). Conclusions: Maternal blood adiponectin concentration is not low in SGA compared with healthy controls. However, SGA shows lower cord blood adiponectin concentration than healthy controls.