Maternal phenotype: how do age, obesity and diabetes affect myometrial function?

Insulin and myometrial contractility; Are there any links? A narrative review

Contrary to the evidence supporting the role for insulin in stimulating uterine contraction, only a limited number of studies have highlighted the inhibitory effect of insulin on myometrial contractions in human and rodent. A hypothetical narrative review of the current literature was conducted, revealing the current literature and shows the potential inhibitory effects of insulin on myometrial contractility. These inhibitory mechanisms include activation of adenylyl cyclase signaling pathways, an increase in cAMP production, a decrease in Ca2 + influx and cytosolic Ca2+, hyperpolarization of the cell membrane, and stimulation of NO synthesis. Altered oxytocin sensitivity, structural similarity to relaxin, modulating abscisic acid (ABA) effect, and synergistic interaction with progesterone, adiponectin, and leptin may also represent additional mechanisms for the inhibitory effects of insulin on myometrial contractions. The literature indicates that insulin exhibits inhibitory effects on myometrial contractility. Confirming such a conclusion through future studies may propose insulin as a possible uterine quiescent.

Assessment of the hypoglycemic effect of Cyanthillium cinereum (L.) H. Rob. and its dual impact on uterine contraction in gestational diabetic rats

Objective

This study investigates the effects of Cyanthillium cinereum (L.) H. Rob. ethanolic extract (CCE) on gestational diabetes mellitus (GDM) in rats using biochemical, histological, and uterine contractility studies.

Methods

Diabetes was induced in pregnant rats using streptozotocin (60 mg/kg). CCE was administered orally at low (50 mg/kg BW) and high (500 mg/kg BW) doses from gestation day 7 to day 21. Maternal evaluations included body weight, gravid uterine weight, and biochemical assays for serum glucose, insulin, lipids, and liver enzymes. Fetal outcomes included fetal size. Histological analyses of maternal pancreatic and uterine tissues and uterine contractility studies using ex vivo muscle strip experiments were also performed.

Results

CCE and metformin (MET) significantly reduced elevated blood glucose levels and improved the Islets of Langerhans area compared to the GDM group (P < 0.05). Both treatments showed a trend toward increased insulin levels (P > 0.05) and significantly reduced lipids, AST, and ALP levels (P < 0.05). High-dose CCE and MET increased gravid uterine weight and fetal size (P < 0.05) while showing a trend toward reducing placental weight and index (P > 0.05). Histological analysis revealed increased fiber area and decreased interstitial space in uterine sections (P < 0.05). Ex vivo, CCE enhanced spontaneous and oxytocin-induced contractions (P < 0.05), while MET had no effect.

Conclusion

CCE reduces elevated glucose levels and exhibits hypolipidemic and hepatoprotective effects, improving maternal and fetal outcomes in GDM. Its uterine contractility effects suggest potential as a complementary therapy to MET for GDM management.

Pharmacological Interventions in Labor and Delivery

While there is not a wide range of pregnancy-specific drugs, there are some very specific high-risk areas of obstetric care for which unique pharmacological approaches have been established. In preterm birth, labor induction and augmentation, and the management of postpartum hemorrhage, these pharmacological approaches have become the bedrock in managing some of the most common and problematic areas of antenatal and intrapartum care. In this review, we summarize the existing established and emerging evidence that supports and broadens these pharmacological approaches to obstetric management and its impact on clinical practice. It is clear that existing therapeutics are limited. They have largely been developed from our knowledge of the physiology of the myometrium and act on hormonal receptors and their signaling pathways or on ion channels influencing excitability. Newer drugs in development are mostly refinements of these two approaches, but novel agents from plants and improved formulations are also discussed.