Could Turmeric Compounds Promote Dangerous Clots?

• What is Fibrinogen?
• Likelihood of Risk

The researchers of one lab study seemed to suggest that turmeric's curcumin compounds may do just that. The study compared curcumin to two drugs — paclitaxel and sirolimus. They are commonly used in polymer films that coat stents. Results showed the following: ^(vii.256)

• Paclitaxel: A chemotherapy drug, paclitaxel blocked absorption of fibrinogen and activation of platelets. However, it also induced bacterial colonies of Salmonella typhimurium and had DNA-damaging effects.
• Curcumin: The turmeric compound showed neither of the negative effects of paclitaxel. Similar to paclitaxel and sirolimus, curcumin reduced levels of unhelpful adhesion molecules. Curcumin also significantly blocked activation of platelets. However, the film made with curcumin showed higher levels of fibrinogen.

Increased Fibrinogen Levels

Based on these results, the researchers implied that it might not be a good idea to use turmeric's curcumin compounds to coat stents. The rationale was because curcumin increased absorption of fibrinogen, a clot-promoting protein. ^(vii.256)

What is Fibrinogen?

High levels of fibrinogen in the blood are considered a symptom and risk factor for heart disease. In normal wound healing, fibrinogen proteins and activated platelets are part of the acute inflammatory response after an injury. It interacts with thrombin proteins to form fibrin. Thrombin is produced when activated platelets cluster at an injury site, and thrombin also activates more platelets. ^{(vii.229, 251)}

Lesions and damage to blood vessels from atherosclerosis chronically activate the wound healing response and can contribute to chronic inflammation. This can lead to clogged arteries. ^(vii.257)

Angioplasty and stent insertion trigger acute wound healing responses. The concern raised with even conventional stents is that the material used to make permanent stents causes chronic inflammation. The artery could close again (restenosis), or even promote formation of a clot that could cause a heart attack. ^{(vii.251, 257)}

The Bottom Line — Measuring Likelihood of Risk

According to experts in biomedical engineering, a number of factors affect whether a substance is likely to promote clot formation. The likelihood is thought to be low if a low number of platelets stick to it and, perhaps more importantly, a low number of platelets are activated. ^(vii.251)

Although much work needs to be done in this complex area of heart treatment, most research indicates turmeric's compounds are safe for stent use: ^{(vii.199, 251, 258)}

• A number of studies in labs and animals demonstrate that turmeric and its curcumin compounds are not clot-forming. In fact, they have antiplatelet and wound-healing properties. Curcumin was specifically used in stent studies because it actually suppresses thrombin and clots. ^{(vii.199, 251, 258)}
• Curcumin blocked platelet activation (even in the study above). This is thought to be the most important criteria for anti-clotting agents. ^{(vii.251, 256)}
• Turmeric compounds (including curcumin) help regulate the initial acute inflammatory response so that it doesn't become chronic in nature. ^{(vii.29, 257)}
• Curcumin also inhibited adhesion molecules in the study above, suggesting it would also counteract potential stickiness of polymer film. ^{(vii.251, 256)}
• A number of other compounds in turmeric also suppress growth factors and enzymes. Unhealthy levels of these proteins are involved in scar tissue formation and restenosis from a stent. Turmeric compounds that may be beneficial in counteracting this activity include: ^(vii.259)
  
  • Caffeic acid ^(vii.20-21)
  • Curcumin ^{(vii.52, 232, 259)}
  • Eugenol ^{(vii.20, 23)}
  • Fisetin ^{(vii.25, 172)}
  • Myricetin ^{(vii.21, 25)}
  • Quercetin ^{(vii.21, 25)}
  • Resveratrol ^{(vii.27, 174)}