Stimulation of contractions in pregnant human myometrium is associated with 5-HT3 receptors

The Role of Platelets in the Pathogenesis and Pathophysiology of Adenomyosis

Widely viewed as an enigmatic disease, adenomyosis is a common gynecological disease with bewildering pathogenesis and pathophysiology. One defining hallmark of adenomyotic lesions is cyclic bleeding as in eutopic endometrium, yet bleeding is a quintessential trademark of tissue injury, which is invariably followed by tissue repair. Consequently, adenomyotic lesions resemble wounds. Following each bleeding episode, adenomyotic lesions undergo tissue repair, and, as such, platelets are the first responder that heralds the subsequent tissue repair. This repeated tissue injury and repair (ReTIAR) would elicit several key molecular events crucial for lesional progression, eventually leading to lesional fibrosis. Platelets interact with adenomyotic cells and actively participate in these events, promoting the lesional progression and fibrogenesis. Lesional fibrosis may also be propagated into their neighboring endometrial-myometrial interface and then to eutopic endometrium, impairing endometrial repair and causing heavy menstrual bleeding. Moreover, lesional progression may result in hyperinnervation and an enlarged uterus. In this review, the role of platelets in the pathogenesis, progression, and pathophysiology is reviewed, along with the therapeutic implication. In addition, I shall demonstrate how the notion of ReTIAR provides a much needed framework to tether to and piece together many seemingly unrelated findings and how it helps to make useful predictions.

Rac1 is involved in uterine myometrium contraction in the inflammation associated preterm birth

Preterm birth (PTB) is a public health issue. The WHO has recommended the use of tocolytic treatment to inhibit preterm labour and improve pregnancy outcomes. Intrauterine inflammation is associated with preterm birth. Rac1 can modulate inflammation in different experimental settings. In the current study, we explored whether Rac1 can modulate spontaneous uterine myometrium contraction in a mouse model of lipopolysaccharide (LPS)-induced intrauterine inflammation. Subsequently, we recorded uterine myometrium contraction and examined uterine Rac1 expression in a mouse model of preterm birth and case in pregnant women by western blotting analysis. We also measured progesterone levels in the blood serum from mice. Murine myometrium was obtained 12 h post LPS treatment. Human myometrium was obtained at the time of caesarean section. We found that in the LPS-treated group of mice, uterine myometrium contraction was enhanced, protein levels and activation of Rac1 were increased and serum progesterone levels were decreased. The protein levels of Rac1 were also increased in preterm birth or case in pregnant women. NSC23766, a Rac1 inhibitor, attenuated uterine myometrium contraction and diminished Rac1 activation and COX-2 expression. Furthermore, silencing of Rac1 suppressed cell contraction and COX-2 expression in vitro. In conclusion, our results suggested that Rac1 may play an important role in modulating uterine myometrium contraction. Consequently, intervening with Rac1 represents a novel strategy for the treatment of preterm birth.

[Use of triptans during pregnancy]

Despite the widespread use of triptans in the treatment of migraine during pregnancy, questions relating to their vasoconstrictive properties have been raised following recent reports of rare fetal deaths and intrauterine growth restrictions. However, to date, analysis of these data does not allow to conclude to a direct effect of triptans, which remain a second line treatment of migraine attacks during pregnancy at any term and under normal conditions of use.

Postpartum Bleeding in Pregnant Women Receiving SSRIs/SNRIs: New Insights From a Descriptive Observational Study and an Analysis of Data from the FAERS Database

PURPOSE

To date, the available data on the relationship between the use of selective serotonin reuptake inhibitors (SSRIs) or the serotonin and norepinephrine reuptake inhibitor (SNRI) venlafaxine and postpartum hemorrhage (PPH) are conflicting and have not been extensively investigated, especially in terms of plasma drug concentrations. We performed data mining of antidepressant-induced PPH reported to the US Food and Drug Administration's Adverse Event Reporting System database, to assess the strength of the potential association between antidepressant pharmacotherapy and PPH in pregnant women. Concurrently, we carried out a descriptive observational population (pregnant women) analysis of the correlation between the plasma concentrations of SSRIs/SNRIs used during pregnancy and the extent of bleeding at delivery.

METHODS

A disproportionality analysis of individual case study reports of PPH associated with SSRIs or venlafaxine in pregnant women was performed. Reporting odds ratio was used as a measure of disproportionality analysis. Pregnant women treated with an SSRI or SNRI (venlafaxine) for depressive or anxiety disorder and who consented to plasma drug concentration monitoring at the time of delivery were recruited. Plasma drug concentration assay was performed according to validated LC-MS/MS. Based on plasma drug concentrations, patients were classified into 1 of 2 groups, in therapeutic range or below therapeutic range for the drug administered, in accordance with the Arbeitsgemeinschaft für Neuropsychopharmakologie und Pharmakopsychiatrie guideline, and correlations with blood loss were identified, with PPH defined as a blood loss of >500 mL.

FINDINGS

Only 43 Individual Case Safety Reports (ICSRs) reported at least one SSRIs or venlafaxine as suspect drug in 14 years (database analyses). Forty-three women were enrolled in the study population (observational study). In 24 patients (55.8%) the plasma drug concentration was below the therapeutic threshold. Unexpectedly, the mean blood loss in the below-range group was significantly higher than that in the in-range group. PPH occurred in 30% of women: in 9.3% and in 20.7% of patients in the in-range and below-range groups, respectively.

IMPLICATIONS

Although preliminary, these data indicate a rather good tolerability profile of SSRIs/SNRIs regarding postpartum bleeding. Moreover, they suggest that keeping the plasma levels of SSRIs/SNRIs low as a precautionary measure does not reduce postpartum bleeding, which was higher in the below-range group. The findings from this study suggest that the use of therapeutic drug monitoring in pregnancy, a period in which multiple variables affect drug metabolism, may allow for better treatment customization, with subsequent advantages in terms of tolerability and efficacy of treatment.

Granisetron reduces the need for uterotonics but not sympathomimetics during cesarean delivery

OBJECTIVE

To assess the effect of a 5-hydroxytryptamine-3 receptor antagonist (granisetron) on the use of sympathomimetic (cafedrine/theodrenaline) and uterotonic (oxytocin) agents after spinal anesthesia during cesarean delivery.

METHODS

A retrospective observational analysis was conducted using intraoperative records (n=240) created at a single hospital in Germany between November 1, 2016, and July 31, 2017. The granisetron group (n=120) had received 3 mg of granisetron immediately before induction of spinal anesthesia. The control group (n=120) had not received granisetron. The primary endpoints were the intraoperative requirements for sympathomimetic and uterotonic agents. The secondary endpoints were parameters of intraprocedural maternal hemodynamic and clinical states.

RESULTS

More patients in the granisetron group than in the control group received intraoperative cafedrine/theodrenaline (P=0.045), with the cumulative intraoperative dosage also increased in the granisetron group (P=0.016). By contrast, the cumulative intraoperative dose of oxytocin was lower in the granisetron group than in the control group (P<0.001). Decreases in heart rate and mean arterial blood pressure were lower in the granisetron group versus the control group (P=0.015 and P=0.002, respectively).

CONCLUSION

Treatment with granisetron immediately before cesarean delivery did not reduce the perioperative requirement for sympathomimetics but did reduce the need for uterotonics. REGISTERED AT CLINICALTRIALS.GOV (NCT03318536).