Prostaglandin analogues and their uses

Determination of Prostaglandins (Carboprost, Cloprostenol, Dinoprost, Dinoprostone, Misoprostol, Sulprostone) by UHPLC-MS/MS in Toxicological Investigations

Prostaglandins have stimulative influence on the human uterus and therefore were introduced to medical treatment in reproductive healthcare as labor inductors or abortifacients. The UHPLC-ESI-QqQ-MS/MS method was developed for six prostaglandins: carboprost, cloprostenol, dinoprost (PGF2α), dinoprostone (PGE2), misoprostol and sulprostone (substances for pregnancy termination) in pharmaceutical samples and was applied for the toxicological examination of pills containing misoprostol (collected during gynecological examination). There were used two internal standards: misoprostol-d5 and PGF2α-d4. The quantification of analytes was performed in the MRM mode. The linearity of method was in the range from 0.1 to 10 µg/mL, with a coefficient of determination above 0.997 (R2) for each compound. The precision and accuracy values did not exceed ±5.0%. Analysis of the pills revealed the presence of two substances: misoprostol and diclofenac. Misoprostol and diclofenac dose per sample were as follows: 608.8 ng (sample 1), 708.4 ng (sample 2), 618.8 ng (sample 3) and 67.7 mg (sample 1), 65.3 mg (sample 2) 67.3 mg (sample 3), respectively. A simple, precise and reliable method can be applied for routine examinations in terms of clinical and forensic toxicology examinations as well as in quality control of drugs for pharmaceutical purposes (original drugs and counterfeit medications).

Accidental overdose of travoprost

PURPOSE

To report systemic symptoms after an overdose of travoprost.

CASE REPORT

We report a patient who, instead of artificial tears, inadvertently used travoprost every 15 minutes for 7 hours after LASIK (laser-assisted in situ keratomileusis) surgery. She experienced abrupt, severe abdominal cramps and sudden, severe menstrual bleeding, which subsided quickly upon discontinuation of the drug.

CONCLUSIONS

Because of the few systemic adverse effects, prostaglandin analogs are widely used for the treatment of glaucoma. Travoprost should be taken once daily; therefore, overdose is extremely uncommon. Systemic prostaglandins have been found to be mediators of uterine activity and are used to induce labor and terminate pregnancies. The high dose of this topical medication, as well as the compromised cornea, makes this case unique. The unusual circumstances observed in this case greatly expand our knowledge regarding the potential adverse effects of travoprost.

Limitations and obstacles of the spontaneous adverse drugs reactions reporting: Two "challenging" case reports

Introduction:

Nowadays, based on several epidemiological data, iatrogenic disease is an emerging public health problem, especially in industrialized countries. Adverse drugs reactions (ADRs) are extremely common and, therefore, clinically, socially, and economically worthy of attention. Spontaneous reporting system for suspected ADRs represents the cornerstone of the pharmacovigilance, because it allows rapid detection of potential alarm signals related to drugs use. However, spontaneous reporting system shows several limitations, which are mainly related to under-reporting. In this paper, we describe two particular case reports, which emphasize some reasons of under-reporting and other common criticisms of spontaneous reporting systems.

Materials and Methods:

We performed a computer-aided search of Medline, PubMed, Embase, Cochrane library databases, national and international databases of suspected ADRs reports in order to identify previous published case reports and spontaneous reports about the ADRs reviewed in this paper, and to examine the role of suspected drugs in the pathogenesis of the described adverse reactions.

Results:

First, we reported a case of tizanidine-induced hemorrhagic cystitis. In the second case report, we presented an episode of asthma exacerbation after taking bimatoprost. Through the review of these two cases, we highlighted some common criticisms of spontaneous reporting systems: under-reporting and false causality attribution.

Discussion and Conclusion:

Healthcare workers sometimes do not report ADRs because it is challenging to establish with certainty the causal relationship between drug and adverse reaction; however, according to a key principle of pharmacovigilance, it is always better to report even a suspicion to generate an alarm in the interest of protecting public health.

Changes in association between previous therapeutic abortion and preterm birth in Scotland, 1980 to 2008: a historical cohort study

BACKGROUND

Numerous studies have demonstrated that therapeutic termination of pregnancy (abortion) is associated with an increased risk of subsequent preterm birth. However, the literature is inconsistent, and methods of abortion have changed dramatically over the last 30 years. We hypothesized that the association between previous abortion and the risk of preterm first birth changed in Scotland between 1 January 1980 and 31 December 2008.

METHODS AND FINDINGS

We studied linked Scottish national databases of births and perinatal deaths. We analysed the risk of preterm birth in relation to the number of previous abortions in 732,719 first births (≥24 wk), adjusting for maternal characteristics. The risk (adjusted odds ratio [95% CI]) of preterm birth was modelled using logistic regression, and associations were expressed for a one-unit increase in the number of previous abortions. Previous abortion was associated with an increased risk of preterm birth (1.12 [1.09-1.16]). When analysed by year of delivery, the association was strongest in 1980-1983 (1.32 [1.21-1.43]), progressively declined between 1984 and 1999, and was no longer apparent in 2000-2003 (0.98 [0.91-1.05]) or 2004-2008 (1.02 [0.95-1.09]). A statistical test for interaction between previous abortion and year was highly statistically significant (p<0.001). Analysis of data for abortions among nulliparous women in Scotland 1992-2008 demonstrated that the proportion that were surgical without use of cervical pre-treatment decreased from 31% to 0.4%, and that the proportion of medical abortions increased from 18% to 68%.

CONCLUSIONS

Previous abortion was a risk factor for spontaneous preterm birth in Scotland in the 1980s and 1990s, but the association progressively weakened and disappeared altogether by 2000. These changes were paralleled by increasing use of medical abortion and cervical pre-treatment prior to surgical abortion. Although it is plausible that the two trends were related, we could not test this directly as the data on the method of prior abortions were not linked to individuals in the cohort. However, we speculate that modernising abortion methods may be an effective long-term strategy to reduce global rates of preterm birth.

[Morbidity of dilatation and evacuation in the second trimester: an analysis]

OBJECTIVE

To compare the rates of complications of dilatation and evacuation (D&E) in the second trimester of pregnancy.

STUDY DESIGN

Retrospective analysis of early complications after D&E in the second trimester (group A: 1988-1994) in comparison with D&E in the first trimester (group B: 1997) and with the induction of abortion by extra-amniotic application of prostaglandins in the second trimester of pregnancy (literature).

RESULTS

The overall complication rate of D&E was statistically significantly higher in the second than in the first trimester (p < 0.0001). The most frequent complication in both groups was a blood loss > 500 ml (p < 0.009). As with blood loss, there was a statistically significant increase in the incidence of postoperative bleeding (p < 0.001) and fever > 38 degrees C (p = 0.042) with rising gestational age, too. We registered similar rates for incomplete abortion, infection, cervical injury, uterine perforation and thrombosis.

CONCLUSION

Second-trimester pregnancy termination with D&E is associated with higher morbidity rates than in the first trimester. Overall, the rates of complications of D&E in our study were acceptable and comparable with the results of previous studies. Compared with the induction of abortion by extra-amniotic prostaglandins, D&E shows lower morbidity rates. In particular, the advantages of D&E are in the early second trimester.

Use of Carboprost to Facilitate Hysteroscopic Resection of Submucous Myomas

Ten women with submucous myomas that could not be completely resected hysteroscopically were treated with intracervical carboprost. This caused uterine contraction and extrusion of the unresectable intramural component into the endometrial cavity. Eleven of 13 myomas in these patients could then be completely resected. One intramural myoma extruded into the endometrial cavity after injection of carboprost and was also completely resected.

Sensitivity of the early luteal phase ovine cervix to prostaglandin E2 (PGE2) and expression of EP3 receptor mRNA

The effects and mechanism of action of prostaglandin E2 (PGE2) on the ovine cervix are largely unknown in the luteal phase. In these studies we have shown that low levels of EP3-receptor (EP3R) mRNA are present in the ovine cervix and that the PGE2 induces activation of polymorphonuclear leukocytes in the ovine cervix on day 6 of the oestrous cycle. It is possible, therefore, that PGE2 acts on the ovine cervix through coupling to EP3 receptors.

Splice variants of the human EP3 receptor for prostaglandin E2

The EP3 receptor for prostaglandin E2 (PGE2) mediates various biological activities such as uterine contraction, inhibition of gastric acid secretion, presynaptic inhibition of neurotransmitter release and potentiation of platelet aggregation. In an attempt to understand the molecular basis of this diversity of biological function, we cloned full-length cDNAs encoding EP3 receptors for PGE2 from human uterus cDNA libraries. Seven cDNA variants were identified which code for six distinct EP3-receptor isoforms. Sequencing revealed that the receptor isoforms differ in their intracellular C-terminal domains. Southern blot experiments indicate that the isoforms are generated by alternative splicing. The EP3-receptor gene is expressed in various tissues with high expression in kidney and pancreas, as demonstrated by Northern blot analysis. All receptors, stably expressed in baby hamster kidney (BHK) cells, bind PGE2 specifically with similar Kd of 2.2-5.8 nM. The binding of [3H]PGE2 is competed with by unlabelled prostaglandins in the order sulprostone (a PGE2-like agonist) approximately PGE2 >> PGF2 alpha > Iloprost (a prostacyclin analogue) > PGD2, which is specific for EP3 receptors. Analysis of the signal-transduction pathways demonstrated that all receptors respond with inhibition of forskolin-induced cAMP accumulation with an IC50 of 0.1-3 nM PGE2. In addition, some isoforms induce an increase in intracellular free calcium ([Ca2+]i) at PGE2 concentrations greater than or equal to 10 nM. These results may offer an explanation for the different physiological responses observed in various tissues following activation of EP3 receptors.