Sulawesi propolis induces higher apoptotic activity and lower inflammatory activity in a rat endometriosis model

Background

Endometriosis has a major impact on women's quality of life. The two primary pathologies are chronic inflammation and altered apoptotic activity. Sulawesi propolis has been shown to have known anti-inflammatory and pro-apoptotic properties in other diseases.

Objective

To investigate the effects of Sulawesi propolis in the rat endometriosis model.

Methods

An autologous endometriosis model was created in 60 female Wistar rats by laparotomy. Rats were divided into four groups (n = 15 in each group): control group (CG), dienogest group (DG), propolis 50 mg/kg body weight (BW)/day (P50) group, and propolis 100 mg/kg BW/day (P100) group. Each treatment group was divided into three different treatment durations (n = 5 in each treatment group): 2, 4 and 6 weeks. After treatment, laparotomy was performed to determine endometriotic tissue growth, apoptosis [caspase-3 and Bcl-2-associated X/Bcl-2 (Bax/Bcl)] and inflammation [prostaglandin-E2 (PGE2) and interleukin-1B (IL-1B)].

Results

A significant difference was seen in endometriotic tissue growth between the P50 group and the CG, with the greatest reduction in the P50 6-week (P50-6) group, reaching 70.66% of the initial area. Highest Bax/Bcl-2 mRNA expression was shown in the P50-4 and P100-4 groups, highest caspase-3 expression was shown in the P50-2 and P50-4 groups, and lowest IL-1B expression was shown in the P50-4 group; all differed significantly from the CG. No significant difference in PGE2S mRNA was found between the groups.

Conclusion

Sulawesi propolis extract suppressed endometriotic tissue growth in the rat model by increasing apoptotic activity. The effects were time-dependent, with 50 mg/kg BW as the optimal dose.

Cytokeratin 8, 18 and 19 in endometrial epithelium of Norplant and norethisterone enanthate injectable progestogen contraceptive users

Cytokeratins 8, 18 and 19 are members of the cytoskeletal intermediate filament family found in all simple epithelia. Intermediate filaments are dynamic intracytoplasmic structures that can be influenced by a number of external factors. Norethisterone enanthate (NET-EN) is a long-acting progestogen contraceptive that has been found to arrest endometrial growth in the rat. Both Norplant and NET-EN cause bleeding problems among users which are responsible for > 50% of withdrawals with these methods. The aim of this study was to explore changes in the expression and distribution of cytokeratins 8, 18 and 19 in NET-EN- and Norplant-exposed endometrial epithelium which could be related to bleeding disturbances. Seven NET-EN and 37 Norplant endometrial biopsies were paraffin-embedded and stained immunohistochemically to evaluate cytokeratin expression and distribution. The results showed that women who had received NET-EN for 3-4 months had a cytokeratin distribution similar to that seen in the normal menstrual cycle. This is in contrast to endometrium from Norplant users in which cytokeratin expression was reduced and the epithelial cells were more rounded. No relationship between cytokeratin expression and breakthrough bleeding pattern was found. NET-EN and Norplant may act differently on endometrial epithelial cytokeratin.

Endometrial biopsy collection from women receiving Norplant

A series of 191 endometrial biopsy procedures were performed on Indonesian women who had received between 3 and 12 months exposure to Norplant. In all, 87 biopsy procedures were attempted with a microhysteroscope using biopsy forceps, and 104 procedures were attempted with either Pipelle or Karman suction curettes. Regardless of the biopsy method, diagnosable endometrium was obtained in only approximately 50% of procedures. Myometrium was often found in microhysteroscope but not in suction biopsies. An analysis of a number of clinical characteristics showed that women from whom diagnosable endometrial tissue was obtained had higher mean peripheral oestrogen concentrations in the 2 weeks prior to biopsy (439 +/- 35 versus 289 +/- 33 pmol/l; P = 0.0018) and significantly more days when endometrial bleeding occurred in the 90 days prior to biopsy (26.5 +/- 2.1 versus 16.2 +/- 1.8; P = 0.0003). These results suggest that after 3-12 months exposure to Norplant approximately 50% of women have an endometrium too thin to sample, and that this group is characterized by lower peripheral oestrogen concentrations and reduced menstrual bleeding.

Clinical evaluation of the therapeutic effectiveness of ethinyl oestradiol and oestrone sulphate on prolonged bleeding in women using depot medroxyprogesterone acetate for contraception. World Health Organization, Special Programme of Research, Development and Research Training in Human Reproduction, Task Force on Long-acting Systemic Agents for Fertility Regulation

A placebo-controlled randomized clinical trial was conducted in six centres to compare the effects of a 14 day treatment with either 50 micrograms ethinyl oestradiol daily or 2.5 mg oestrone sulphate daily, on depot medroxyprogesterone acetate (DMPA)-induced prolonged bleeding. Out of 1035 women admitted to the study, 278 requested treatment and were given ethinyl oestradiol (n = 90), oestrone sulphate (n = 91) or placebo (n = 97). Ethinyl oestradiol was successful in stopping the bleeding episode in 93% of cases, compared with oestrone sulphate and placebo which had success rates of 76 and 74% respectively. However, the relative advantage of ethinyl oestradiol was marginal, with an average reduction of 1 bleeding day and 3 spotting days compared with the other two groups. Immediately after treatment, women given ethinyl oestradiol had less bleeding but a more unpredictable pattern than the other two groups. In the long term, there were no differences between the bleeding patterns or the discontinuation rates for any reason in the three groups, and the most important single reason for discontinuation in those groups remained 'menstrual problems'. In summary, the study showed that treatment of DMPA-induced prolonged bleeding with ethinyl oestradiol had a limited short-term effect but no beneficial effect on the acceptability of DMPA as a contraceptive method. Treatment with oestrone sulphate was no different from placebo.

Endometrial angiogenic response in Norplant users

The levonorgestrel-releasing subdermal contraceptive implant Norplant is well accepted among Indonesian users, despite the problems with irregular and prolonged menstrual bleeding. Bleeding can be the major reason for women discontinuing their use of Norplant. The causes of endometrial bleeding may include disturbances in endometrial regeneration and angiogenesis. The aim of this study was to investigate endometrial angiogenic activity in Norplant users and to compare it to that in the normal menstrual cycle. The study also aimed to determine the correlation between endometrial angiogenic activity and plasma concentrations of oestradiol, progesterone, sex hormone binding globulin and levonorgestrel, as well as the free levonorgestrel index. The subjects for this study were selected from Norplant users with an exposure of between 3 and 12 months. Endometrial angiogenic response was assayed using an endothelial cell migration assay. Six blood samples to monitor oestradiol and progesterone concentrations were taken during the 2 weeks prior to endometrial biopsy. Samples for the analysis of sex hormone binding globulin and levonorgestrel were taken on the day of biopsy. The results showed that the median score of endometrial angiogenic activity in the 30 women used as controls were significantly higher than the 40 Norplant acceptors (z = -3.80, one tail, P < 0.001). There was no significant correlation between the endothelial migration score and peripheral hormonal concentrations or the free levonorgestrel index in Norplant users. There was no difference in the endometrial angiogenic activity in endometrium with and without bleeding problems. However, it is interesting to note that four Norplant acceptors who had an endothelial cell migration score > or = 1.0 had the lowest free levonorgestrel index.

Reduced endothelial cell migratory signal production by endometrial explants from women using Norplant contraception

Bleeding problems can be one of the major reasons for women to discontinue the use of hormonal contraceptives. Causes of endometrial bleeding can include disturbances in endometrial regeneration and angiogenesis. Endothelial cells migrate and proliferate rapidly as part of the angiogenic process under the influence of appropriate stimuli. The aim of this study is to investigate the production of endothelial cell migratory signals by endometrial explants from women receiving Norplant and to compare it to that of those with a normal menstrual cycle. The subjects were selected from Norplant users with an exposure of 3-9 months. The endothelial cell migratory signal production was assayed using the Folkman method (1989), modified by Rogers (1992). Blood serum concentrations of oestradiol, progesterone and sex hormone binding globulin were monitored for 2 weeks prior to endometrial biopsy. Endothelial cell migration toward endometrial explants of 30 women as control and 46 Norplant acceptors was assayed. The results showed that endothelial cell migratory activity toward endometrial explants from the control group was significantly higher than toward those from Norplant acceptors (z = 3.89, P < 0.001). There were no differences between endometrial endothelial cell migratory activities in Norplant acceptors with bleeding or without bleeding problems.

Cytokeratins 8, 18 and 19 in endometrial epithelial cells during the normal menstrual cycle and in women receiving Norplant

Cytokeratins 8, 18 and 19 are members of the cytoskeletal intermediate filament protein family. They are expressed in all simple epithelial tissues, including endometrium, and are recognised as dynamic structures that can be affected by numerous external factors. The Norplant system is a subdermal slow release levonorgestrel implant commonly used as a long-acting progestogen contraceptive. Norplant implants have been shown to have atrophic effects on endometrial epithelial and stromal cells, and cause a range of endometrial bleeding problems among users. The aim of this study is to describe changes in the immunohistochemical expression and distribution of cytokeratins 8, 18 and 19 in endometrial epithelial cells of Norplant implants users and normal menstrual cycle controls. Endometrial biopsies were collected from 65 control normal cycle women and 37 Norplant implants acceptors. The normal menstrual cycle was classified histologically into 9 stages; one menstrual, five proliferative and three secretory. Norplant implants bleeding patterns were categorised into 6 groups according to current World Health Organisation (WHO) definitions; amenorrhoea, frequent bleeding, infrequent bleeding, irregular bleeding, "normal" bleeding, and prolonged bleeding. The tissues were fixed in formalin, embedded in paraffin, and stained immunohistochemically. Semi-quantitative scoring of the staining intensity was performed. Apical versus basal intracellular cytokeratin distribution was also evaluated. The staining intensity was significantly stronger in control endometrial tissue compared to Norplant implants tissue. In control tissues, cytokeratins were predominantly located in the apical region of epithelial cells (52% of biopsies) and in Norplant implants tissues they were predominantly distributed equally between the apical and basal portions of epithelial cells (43% of biopsies). There was no particular cytokeratin distribution pattern associated with the different stages of normal cycle or the different Norplant implants bleeding patterns. It was concluded that long-term exposure to levonorgestrel significantly reduced the cytokeratin expression in endometrial epithelial cells (P < 0.001).

Five-year experience with Norplant

At Klinik Raden Saleh, Department of Obstetrics and Gynaecology, University of Indonesia, from 1 May until 31 August, 1981, Norplant contraceptive implants were inserted into 437 Indonesian women. The continuation rates of Norplant at first, second, third, fourth and fifth year were, respectively, 96%, 92%, 88%, 82% and 78%. Bleeding problems were the most common cause for removal. The cumulative five-year net pregnancy rate for Norplant was 1.8 per 100 women. The Norplant contraceptive system is thus seen to combine the highest acceptability as measured by its continuation rate with the highest long-term effectiveness among the available temporary contraceptive methods.

Pregnancy after removal of Norplant implants contraceptive

Many concerns have been expressed regarding the introduction of a new contraceptive method into family planning programmes. One of the concerns is the return of fertility after discontinuing the method. To evaluate the subsequent fertility status of the Indonesian women after removal of Norplant, a prospective longitudinal study was undertaken in Klinik Radeb Saleh, Jakarta. Fifty-one women whose Norplant were removed because of their wish to become pregnant were followed-up for a period of two years or until pregnancy occurred, whichever was earlier. Two groups of women who had Lippes C IUD removed or discontinued the use of DMPA for planning pregnancy served as control and were followed-up for equal length of time. The cumulative conception rate for ex-Norplant users, ex-IUD users and ex-DMPA users at one year was 76.5, 74.7 and 70.2 per 100 women, respectively. There was no significant difference between the groups (p greater than 0.05). The present study, along with other studies, indicate that the prolonged use of Norplant do not impair the return of fertility.