Studies on female genital tract infections and the role of nitric oxide in diagnosis

Female genital tract infections are among the most common conditions causing individuals to seek medical care, and are associated with a high gynaecologic and reproductive morbidity. Thus, prompt and precise diagnosis of genital tract infections is essential to institute effective therapy and prevent sequelae. It is therefore desirable to develop an easily performed, objective test that can be useful to the practicing physician. Local measurement of nitric oxide (NO) gas in hollow organs has been used to detect and monitor inflammatory processes, but as of today NO has not been studied in the female genital tract. The aim of the present thesis was to investigate whether it is possible to measure accurate NO formation in the female genital tract. We also sought to explore the role of NO as a diagnostic marker for inflammation in the female genital tract. Finally we wanted to evaluate the effect of bacterial vaginosis (BV) on the pharmacokinetics (plasma concentration Cmax, Tmax and bioavailability measured as the AUC240) of vaginally administered misoprostol in the first trimester of pregnancy. NO has a very short half-life in biological tissues, but it is more stable in the gaseous phase, which makes it possible to measure this free radical in luminal structures. We have developed a new method for measurement of luminal NO formation involving the insertion of a silicon catheter in the vagina or the uterine cavity. The balloon is filled with air, which is incubated in the vagina or the uterine cavity for sampling of NO from the vagina or the uterus respectively. We observed an almost 100-fold increase in intrauterine concentration of NO in patients diagnosed with pelvic inflammatory disease compared to those diagnosed with appendicitis or healthy controls. Uterine NO levels were uniformly low in healthy women throughout the menstrual cycle. Intrauterine NO levels did not rise after manipulation in the uterine cavity, and after an incubation time of just two minutes, NO levels were significantly increased in patients with diagnosed PID compared to control subjects. Moreover, in patients with symptoms of vaginitis, NO concentration was almost 100-fold increased compared to healthy controls. Vaginal NO levels were uniformly low among healthy women, both of reproductive age and in menopause. Finally, we observed that the bioavailability of misoprostol was reduced in patients with BV, but there was no significant difference in the pharmacokinetics of vaginally administered misoprostol between the patients with BV and healthy control subjects. In conclusion, BV did not affect the pharmacokinetics of vaginally administered misoprostol in early pregnancy. Furthermore, we describe a simple, reliable, rapid, safe and well tolerated method for measuring NO in the female genital tract. We also suggest that NO could be further evaluated as a biomarker of inflammatory disease in the female genital tract

High-mobility group box protein 1 and its signalling receptors in human preterm and term cervix

The objective of this study was to identify possible changes in mRNA and protein expression of high-mobility group box protein 1 (HMGB1) and its suggested receptors - receptor for advanced glycation end-products (RAGE) and Toll-like receptor 2 (TLR2) and TLR4 - in human cervix during pregnancy, term and preterm labor. Cervical biopsies were taken from 58 women: 20 at preterm labor, 24 at term labor, 10 at term not in labor and 4 from non-pregnant women. Real-time RT-PCR was used to quantify mRNA expression, and immunohistochemistry and ELISA for protein analysis. HMGB1, RAGE, TLR2 and TLR4 proteins were localized and their mRNA expression was detected in the cervix. There was more extranuclear HMGB1 in the cervical epithelium and stroma in preterm and term labor compared to the term not in labor. TLR2 mRNA expression was upregulated 5-fold in term labor and 3-fold in preterm labor compared to term not in labor and non-pregnant controls. There was lower expression of TLR2 and TLR4 mRNAs in preterm labor compared to term. Lower mRNA expression of HMGB1 was found in the subgroup with preterm premature rupture of membranes than in the rest of the preterm group, where levels were significantly higher than in term labor. In conclusion, extranuclear expression of HMGB1 during labor suggests a possible role of HMGB1 during the process of cervical ripening. Changes in expression of mRNAs encoding HMGB1, TLR2 and TLR4 in preterm labor suggest differences in the mechanism of cervical ripening at preterm and term delivery. (C) 2009 Elsevier Ireland Ltd. All rights reserved