Vitamin E Reduces Inflammation
A new study investigated the anti-inflammatory activity of a common antioxidant vitamin. Pro-inflammatory cellular mediators such as interleukin-6, nitric oxide, tumor necrosis factor-alpha, prostaglandin E2 and gene expression of the pro-inflammatory enzyme cyclooxygenase-2 can be measured to evaluate inflammatory status.
In this study, researchers evaluated tocotrienols for their anti-inflammatory activity. Tocotrienols are members of the vitamin E family. There are 8 forms of vitamin E, including the four well-known types of tocopherols (alpha, beta, gamma, and delta) and the four tocotrienol isoforms (alpha, beta, gamma, and delta). In addition to their antioxidant properties, tocotrienols have been shown to have anti-mutagenic, neuroprotective and cholesterol-lowering activity.
Researchers exposed macrophages, a type of phagocytic white blood cell, to lipopolysaccharide, a bacterial endotoxin that elicits an inflammatory response. The macrophages were treated with the combination of all four isoforms of tocotrienols and evaluated for changes in pro-inflammatory mediator production. Additionally, the effectiveness of each tocotrienol isoform was compared to each of the other isoforms, as well as in combination, to evaluate the specific effectiveness of each type.
The results showed that lipopolysaccharide exposure induced the production of several pro-inflammatory mediators. Treatment with the tocotrienols significantly inhibited the production of pro-inflammatory mediators, including interleukin-6 and nitric oxide. In addition, alpha-tocotrienol significantly lowered tumor necrosis factor-alpha production, and alpha-, beta-, and delta-tocotrienols reduced prostaglandin E2 levels. Furthermore, beta-, gamma-, and delta-tocotrienols down-regulated the gene expression of the cyclooxygenase-2 enzyme.
The researchers stated, "Collectively, the data suggested that tocotrienols are better anti-inflammatory agents than alpha-tocopherol and the most effective form is delta-tocotrienol."
Yam ML, Abdul Hafid SR, Cheng HM, Nesaretnam K. Tocotrienols suppress proinflammatory markers and cyclooxygenase-2 expression in RAW264.7 macrophages. Lipids. 2009 Sep;44(9):787-97.