Tocotrienols: A Family of Molecules with Specific Biological Activities.
Raffaella ComitatoRoberto AmbraFabio VirgiliPublished in: Antioxidants (Basel, Switzerland) (2017)
Vitamin E is a generic term frequently used to group together eight different molecules, namely: α-, β-, γ- and δ-tocopherol and the corresponding tocotrienols. The term tocopherol and eventually Vitamin E and its related activity was originally based on the capacity of countering foetal re-absorption in deficient rodents or the development of encephalomalacia in chickens. In humans, Vitamin E activity is generally considered to be solely related to the antioxidant properties of the tocolic chemical structure. In recent years, several reports have shown that specific activities exist for each different tocotrienol form. In this short review, tocotrienol ability to inhibit cancer cell growth and induce apoptosis thanks to specific mechanisms, not shared by tocopherols, such as the binding to Estrogen Receptor-β (ERβ) and the triggering of endoplasmic reticulum (EndoR) stress will be described. The neuroprotective activity will also be presented and discussed. We propose that available studies strongly indicate that specific forms of tocotrienols have a distinct mechanism and biological activity, significantly different from tocopherol and more specifically from α-tocopherol. We therefore suggest not pooling them together within the broad term "Vitamin E" on solely the basis of their putative antioxidant properties. This option implies obvious consequences in the assessment of dietary Vitamin E adequacy and, probably more importantly, on the possibility of evaluating a separate biological variable, determinant in the relationship between diet and health.
Keyphrases
- estrogen receptor
- endoplasmic reticulum
- oxidative stress
- preterm infants
- gestational age
- healthcare
- mental health
- anti inflammatory
- physical activity
- public health
- cell death
- weight loss
- squamous cell carcinoma
- endoplasmic reticulum stress
- heat stress
- cell proliferation
- blood brain barrier
- young adults
- brain injury
- cell cycle arrest
- stress induced
- health promotion
- lymph node metastasis