Clarithromycin and telithromycin increases interleukin-10 expression in the rat endometriosis model

Emerging bacterial factors for understanding pathogenesis of endometriosis

The pathogenesis of endometriosis is a complex process, and recent research has introduced novel hypotheses in this field. This review summarizes recent studies on the pathogenesis of endometriosis. We focused on several classical hypotheses, as well as their interactions with the microenvironment of hormonal dependence and immunosuppression. Furthermore, we highlighted the emergence of bacterial factors associated with endometriosis. Recent advances in next-generation sequencing (NGS) have revealed the presence and detailed distribution of these bacteria as well as the involvement of specific bacteria in pathogenesis. These factors alter the microenvironment in the early stages of endometriosis development, leading to lesion formation. Understanding the mechanisms underlying the early development of endometriosis from a new perspective would be helpful for the development of novel therapeutic agents for endometriosis.

Clarithromycin prevents preterm birth and neonatal mortality by dampening alarmin-induced maternal–fetal inflammation in mice

Background

One of every four preterm neonates is born to a woman with sterile intra-amniotic inflammation (inflammatory process induced by alarmins); yet, this clinical condition still lacks treatment. Herein, we utilized an established murine model of sterile intra-amniotic inflammation induced by the alarmin high-mobility group box-1 (HMGB1) to evaluate whether treatment with clarithromycin prevents preterm birth and adverse neonatal outcomes by dampening maternal and fetal inflammatory responses.

Methods

Pregnant mice were intra-amniotically injected with HMGB1 under ultrasound guidance and treated with clarithromycin or vehicle control, and pregnancy and neonatal outcomes were recorded (n = 15 dams each). Additionally, amniotic fluid, placenta, uterine decidua, cervix, and fetal tissues were collected prior to preterm birth for determination of the inflammatory status (n = 7–8 dams each).

Results

Clarithromycin extended the gestational length, reduced the rate of preterm birth, and improved neonatal mortality induced by HMGB1. Clarithromycin prevented preterm birth by interfering with the common cascade of parturition as evidenced by dysregulated expression of contractility-associated proteins and inflammatory mediators in the intra-uterine tissues. Notably, clarithromycin improved neonatal survival by dampening inflammation in the placenta as well as in the fetal lung, intestine, liver, and spleen.

Conclusions

Clarithromycin prevents preterm birth and improves neonatal survival in an animal model of sterile intra-amniotic inflammation, demonstrating the potential utility of this macrolide for treating women with this clinical condition, which currently lacks a therapeutic intervention.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04764-2.

Anti-inflammatory cytokines in endometriosis

Although the pathogenesis of endometriosis is not fully understood, it is often considered to be an inflammatory disease. An increasing number of studies suggest that differential expression of anti-inflammatory cytokines (e.g., interleukin-4 and -10, and transforming growth factor-β1) occurs in women with endometriosis, including in serum, peritoneal fluid and ectopic lesions. These anti-inflammatory cytokines also have indispensable roles in the progression of endometriosis, including by promoting survival, growth, invasion, differentiation, angiogenesis, and immune escape of the endometriotic lesions. In this review, we provide an overview of the expression, origin, function and regulation of anti-inflammatory cytokines in endometriosis, with brief discussion and perspectives on their future clinical implications in the diagnosis and therapy of the disease.

Effects of clarithromycin on inflammatory markers and clinical manifestations in postsurgical follow-up of patients with endometriosis: a double-blinded randomized placebo-controlled clinical trial

PURPOSE

Studies showed anti-inflammatory and immunomodulatory effects of macrolide antibiotics such as clarithromycin in endometriosis. Therefore, the present study aims to investigate the therapeutic efficacy of clarithromycin in patients with endometriosis.

METHODS

This was a double-blinded randomized placebo-controlled trial conducted on endometriotic women during March 2016-2017 in Dena Hospital, Shiraz, Iran. Immediately after surgery, the patients were randomly divided into clarithromycin (real) (n = 120) and placebo group (n = 169). The real group received 500 mg of clarithromycin everyday for 6 months and the placebo group received the placebo. The serum levels of tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), Erythrocyte sedimentation rate (ESR) and C-reactive protein as well as clinical symptoms at baseline and 3 and 6 months of post-surgery were compared within and between groups.

RESULTS

The scores of dysmenorrhea, dyschezia, dyspareunia, and non-menstrual pain significantly decreased in both real and placebo groups compared with the baseline values. However, the real group showed greater reductions compared with the placebo group (p < 0.001). Similarly, the serum levels of CRP, TNF-α, and IL-10 decreased in both groups compared with the baseline values, but the real group showed greater reductions. Interestingly, the reductions in the clinical symptoms and serum levels did not significantly differ between the real and placebo groups. Moreover, the reductions in the studied variables showed no dependence on the time.

CONCLUSION

Clarithromycin may be an appropriate treatment in endometriotic patients. However, the non-significant differences between the real and placebo groups necessitate further studies on the therapeutic efficacy of clarithromycin.

Clarithromycin regresses endometriotic implants in rat endometriosis model

The aim of this study was to investigate the effect of clarithromycin in rat endometriosis and its association with matrix metalloproteinase-9 (MMP-9) expression. After surgical induction of endometriosis, 27 rats were randomised into three groups. Size of endometriotic implants were evalutated and rats in group I (n = 9) were given 100 mg/kg/day of oral clarithromycin, rats in group II (n = 9) were given single 1 mg/kg s.c. injection of leuprolide acetate and rats in group III (n = 9) were not given any medication for 21 days. At the end of 21 days of medication, remaining 23 rats were sacrificed to evaluate morphological and histological features of implants. There was a significant difference between the groups in implant volumes (p = 0.004) before and after medication. Regression of implants were significantly higher in groups I and II than that in control group (p = 0.009 and p = 0.011, respectively). After medication, in group I the implant volume decreased from 62 (12-166) mm(3) to 26 (3-87) mm(3) (p = 0.012) and in group II the volume decreased from 224 (76-1135) mm(3) to 62 (26-101) mm(3) (p = 0.028). There was a significant difference between groups in histopathological score (p = 0.024). The epithelial immunohistochemical score of MMP-9 was significantly lower in group II than that in control group (p = 0.014). In conclusion, clarithromycin regresses endometriotic implants in rats, but not via MMP-9.

Association between interleukin-10 promoter polymorphisms and endometriosis: a meta-analysis

To investigate the influence of the interleukin-10 gene promoter polymorphisms on the susceptibility of endometriosis, we examined the association by performing a meta-analysis. The PubMed, Embase, HuGE Navigator and CNKI were searched to identify eligible studies. We then conducted a meta-analysis to examine the association between interleukin-10 gene promoter polymorphisms and endometriosis. Eight case-control studies which examined the association between the IL-10 gene promoter polymorphisms and the susceptibility to endometriosis were finally included in the meta-analysis. Meta-analysis of the IL-10 -592 A/C polymorphisms showed a significant increased risk of endometriosis in the overall and Asian population in all genetic models and allele contrast. However, meta-analysis of the IL-10 -1082 A/G and IL-10 -819 T/C polymorphisms showed no association with endometriosis in all genetic models and allele contrast in the overall and Asian population samples. In addition, there was not a significant association between the IL-10 -592 A/C gene promoter polymorphisms with the severity of endometriosis. In conclusion, this meta-analysis suggests that the IL-10 -592 A/C polymorphisms conferred susceptibility to endometriosis. However, no associations were found between the IL-10 -1082 A/G and -819 T/C polymorphisms and susceptibility to endometriosis. Further studies are required to elucidate these associations more clearly.

Expression profile of extracellular matrix and adhesion molecules in the development of endometriosis in a mouse model

Ectopic endometrial tissue induces various reactions in surrounding tissues, such as the surface of the ovary and peritoneal cavity, leading to endometriosis. The aim of this study is to investigate the expression profile of extracellular matrix (ECM) and adhesion molecules in the early steps of development of experimental mouse endometriosis, specifically in peritoneum adjacent to endometrium transplants attached via autotransplantation. The endometriosis model was induced by autotransplantation of endometrium to peritoneal tissue. Peritoneal tissues adjacent to the transplant were obtained at 1, 4, and 7 days posttransplantation. The results showed that messenger RNA expression levels of most of the integrins, collagens, and other ECM reached a peak at 7 days posttransplantation. Uniquely, Lamc2 was significantly increased to its maximum level within 24 hours posttransplantation and may be strongly associated with initiation of the development of endometriosis. These data will be helpful in further investigations of the treatment of endometriosis.