Friday, 25 June 2010

A Seminal Paper

There are many external factors that we suspect may play a role in the growth and development of endometriotic lesions. The main contenders being environmental toxicants such as dioxin or bisphenols which are thought to disrupt the body’s normal hormonal balance. Other factors that have been suggested include metals like lead and cadmium, eating red meat or trans fats and alcohol consumption. However, a recent study has identified another potential candidate, semen.

Yes that’s right, a study from Japan has found that seminal fluid increases the growth of endometriotic cells in culture. The logic behind the original thinking is that seminal fluid contains a lot of macromolecules, a rather nonspecific term that in this context refers to factors which may lead to the growth of endometrial tissue. This study found that when seminal fluid plasma was added to endometrial cells from women with and without endometriosis it stimulated growth of these cells. What is interesting is the finding that normal endometrium from women with endometriosis displayed increased growth over normal endometrium from women without endometriosis. This suggests that even the normal endometrium from women with endometriosis is somehow more sensitive to growth signals. This lends some support to the retrograde menstruation theory. If endometrial cells are somehow ‘primed’ for increased growth capacity in some women, then when these cells are refluxed they will be more likely to implant, proliferate and eventually form endometriotic lesions.

The growth signals in question that are found in seminal fluid are hepatocyte growth factor (HGF), estrogen and prostaglandin E2 (PGE2). PGE2 in particular has been touted as a major factor regulating a number of processes essential for developing and sustaining endometriosis.

Now you may very well ask, as I did “how does seminal fluid come into contact with endometriotic lesions?” After all endometriotic lesions are found on the outside of the pelvic organs. Apparently seminal fluid can come into contact with endometriotic lesions via “hematogenous dissemination or direct tissue perfusion through the anterior or posterior vaginal formix after sexual intercourse” which basically means it can diffuse through the rear wall of the vagina much like water diffusing through a sponge. I need to point out though that this does not suggest endometriosis can be caused by unprotected sex, but it may irritate the existing endometriosis.

However, on the other side the macromolecules found in seminal fluid promotes the development and implantation of the embryo, which is good if you are trying to conceive. Of course, as with any new findings there is more work to be done before we draw any definitive conclusions, further studies may prove or dispose what has been found.

Monday, 14 June 2010

Fat of the land

Talk of endometriosis and the role of diet is bound to crop up sooner or later. Some women have found that changes to their diet can help reduce the symptoms of endometriosis, some women find that certain foods make their symptoms worse, particularly if they have bowel symptoms.

Some studies have found that women who consume higher levels of fish oil experience less pain symptoms, although it could be that higher fish consumption is merely an indicator of a healthier lifestyle overall. Other studies agree that a diet high in green vegetables and fruit is associated with a decreased risk of endometriosis, whereas a diet high in red meat was found to increase the risk of developing endometriosis. Again though, these dietary factors are probably related to overall lifestyle health.

Recently a study from the Harvard Medical School found that consumption of certain types of fats was associated with an increased risk in endometriosis. This study used data from the Nurses’ Health Study II cohort, a very large repository of information on 116,607 registered female nurses in the US. Information has been collected from 1989 to 2001 and includes data on illness, environmental and lifestyle factors, so it’s a great source of information about the relationship between risk factors and illness. The aforementioned study looked at data on the 1199 cases of laparoscopically confirmed endometriosis and compared it with data from a food frequency questionnaire. This is what they found.

Total fat intake was not associated with any significant increased risk for developing endometriosis

There was a suggestion that animal fat intake may lead to an increased risk of developing endometriosis, which agrees with the studies mentioned previously that suggested increased consumption of red meat increases the risk of developing endometriosis. Although, intakes of the main components of animal fats i.e. saturated fat and monounsaturated fat were not associated with an increased risk of endometriosis.

Intake of trans-unsaturated fats was associated with a higher risk of endometriosis, with the risk becoming higher if protein intake was also increased.

Intake of long chain omega-3 fatty acids was associated with a decreased risk of endometriosis.

In this prospective study of US nurses the main sources of the seemingly protective long chain omega-3 fatty acids were salad dressing, tuna and dark fish. The major sources of trans-unsaturated fats were fried foods, margarine and crackers.
These results appear to show that a diet high in trans-fats increases the risk of developing endometriosis. However, it may be (and I’m probably sounding like a stuck record now) that a person who has a diet high in trans-fats, does not have a healthy lifestyle compared to someone who eats a lot of omega-3 containing foods. Therefore, the people who eat a lot of omega-3 are not necessarily at a decreased risk of endometriosis because they eat omega-3, but because their lifestyle is healthier overall. You may very well ask “if endometriosis is a disease you are born with, does diet really make that much difference?” Well it could be that having a consistently healthy lifestyle from an early age somehow suppresses the disease much in the same way as a healthy lifestyle can stave off cancer in those with a family history of the disease.

And, if nothing else, it’s another good reason to get trans-fats out of your diet, because although they taste delicious, they’ll make you fat and prone to heart attacks.