New Molecular Targets for the Treatment of Endometriosis-Associated Pain

The study identifies potential new targets for alleviating chronic pelvic pain that afflicts many women with endometriosis.

The study identifies potential new targets for alleviating chronic pelvic pain that afflicts many women with endometriosis.

A new study published in the scientific journal Redox Biology shows that molecules called microRNAs could be a potential new target to combat endometriosis-associated pain.

The idea of the study came from the knowledge that the peritoneal fluid (PF) of women with endometriosis contains many molecules that can cause inflammation and pain. The peritoneal fluid is the liquid that surrounds our organs in the abdomen, and those molecules likely derive from endometrial tissue present in there.  Previously the authors had shown that lipoproteins, a normal constituent of the PF, are oxidized in the PF of women with endometriosis. When oxidized, those molecules play a key role in endometriosis-associated pain. 

In the new study, the authors exposed an endometrial cell line to PF donated by women that were suffering from endometriosis either with pain or not. The same treatment but using PF donated by women that were not suffering from endometriosis served as a control. In addition, cells from the same line were exposed to purified oxidized lipoproteins.

The researchers observed that the expression of several microRNAs was reduced in the cells treated with PF obtained from women suffering from endometriosis with pain and similarly in the cells treated with oxidized lipoproteins. Importantly, those specific microRNAs usually limit the expression of genes that cause inflammation and pain but now their beneficial role was reduced. Indeed, the authors were able to measure an increase in the expression of some of the inflammation and pain causing genes.

MicroRNAs are so called because they are very small RNA molecules. Like DNA, the molecular constituent of our genes, RNA is a nucleic acid and it is found in cells. However, unlike DNA we do not persistently inherit RNA from our parents but we transcribe it from the DNA in our cells.  MicroRNAs are essential regulatory components that keep the expression of our genes in check. Therefore their own production is strictly regulated.

The importance of the new findings is that oxidative stress causes a reduction in the levels of microRNAs that control the expression of inflammation and pain causing genes.

The authors conclude that antioxidants that suppress the oxidation of lipoproteins could be beneficial for the treatment of endometriosis-associated pain.  They also suggest that by targeting those microRNAs directly, new and perhaps more effective therapies could be developed in the future.

Research Source: https://www.ncbi.nlm.nih.gov/pubmed/28499250