ZAG and Endometriosis: Could this Protein Offer Clues to a Devastating Disease

It’s funny sometimes how a solitary clue can lead one on a remarkable journey of discovery. That happened last week when the good folks from the Endometriosis Research Center posted an abstract on social media about a potential new biomarker to diagnose endometriosis. Published in the Journal of Cell Physiology, researchers found that women with endometriosis have significantly higher concentrations of protein called Zinc-alpha2-glycoprotein, ZAG for short, compared to healthy women. Could high levels of ZAG be diagnostic of endometriosis leaving behind the existing, invasive method of laparoscopic visualization? Probably not, but it may be a huge clue to how the immune system functions in the face of chronic, lipid-based and likely toxicant-induced, inflammation. Truth be told, before stumbling upon this abstract (full disclosure, I did not have access to the full article), I had no idea what ZAG was or did; had never heard of it. It turns out, ZAG is a protein discovered about 50 years ago that is involved with lipolysis – fat metabolism. Individuals who are leaner have higher ZAG levels compared to those who carry more weight. ZAG is also involved in cell proliferation and differentiation, cell adhesion, immunoregulation and melanin synthesis (with a potential role in vitiligo). It is ZAG’s role in immune regulation that I find most interesting, but before we get to that, let’s run through a little basic ZAG biochemistry.

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