APS is characterised by the production of antibodies directed at phospholipids, the main components of cell membranes.
While in low risk pregnancies, APS is linked with a nine-fold increase in miscarriage; there is a 90 percent risk of miscarriage associated with APS in case of high-risk pregnancies (women who have had at least three prior losses).
"Statins may work as a treatment for women with APS-induced pregnancy complications. They are drugs that have been shown to be very safe. There are a lot of women who continue to take statins through pregnancy and the drugs have not been shown to produce birth defects," said Guillermina Girardi, Ph.D., associate scientist at Hospital for Special Surgery in New York, who is lead author of the study.
Statins do not increase the risk of bleeding like anticoagulants, which is the current treatment for patients with APS.
The researchers examined the white blood cells from mice that had APS and discovered that these cells expressed certain receptors called PAR2 (protease-activated receptor 2). The receptor, when stimulated, led to the activation of white blood cells that attacked the placenta and hurt the foetus. The researchers inhibited white blood cell activation by using an antibody that blocks tissue factor interaction with PAR-2.
It was found that statins not only downregulate tissue factor, but they also downregulate PAR-2 on white blood cells, making the cells less sensitive.
Thus, the researchers injected statins into mice with APS and found that these drugs could prevent white blood cell activation and protect pregnancies.
During pregnancy, women are usually advised to discontinue most medications, including statins, but Girardi said that no foetal defects have been reported in women who have continued to use statins while pregnant.
The researchers said that careful studies should be conducted to confirm the safety of statins in pregnancy in humans.
"Women that are antiphospholipid antibody positive and have a history of previous miscarriages are a good group to perform a clinical trial," said Girardi.
This study could also have implications for other conditions.
"The study reveals a relationship between tissue factor and PAR2 in inflammation that could have implications for understanding chronic inflammatory conditions such as rheumatoid arthritis," he said.
By finding a way to manipulate tissue factor and PAR2, researchers could lead to treatments for diseases like sepsis, atherosclerosis, Cohn's disease, and lupus.
The study is published in the latest issue of the Journal of Clinical Investigation.