Vitamin E Nicotinate

Abstract

Vitamin E refers to a family of compounds that function as lipid-soluble antioxidants capable of preventing lipid peroxidation. Naturally occurring forms of vitamin E include tocopherols and tocotrienols. Vitamin E in dietary supplements and fortified foods is often an esterified form of α-tocopherol, the most common esters being acetate and succinate. The vitamin E esters are hydrolyzed and converted into free α-tocopherol prior to absorption in the intestinal tract. Because its functions are relevant to many chronic diseases, vitamin E has been extensively studied in respect to a variety of diseases as well as cosmetic applications. The forms of vitamin E most studied are natural α-tocopherol and the esters α-tocopheryl acetate and α-tocopheryl succinate. A small number of studies include or focus on another ester form, α-tocopheryl nicotinate, an ester of vitamin E and niacin. Some of these studies raise the possibility of differences in metabolism and in efficacy between vitamin E nicotinate and other forms of vitamin E. Recently, through metabolomics studies, we identified that α-tocopheryl nicotinate occurs endogenously in the heart and that its level is dramatically decreased in heart failure, indicating the possible biological importance of this vitamin E ester. Since knowledge about vitamin E nicotinate is not readily available in the literature, the purpose of this review is to summarize and evaluate published reports, specifically with respect to α-tocopheryl nicotinate with an emphasis on the differences from natural α-tocopherol or α-tocopheryl acetate.

Paraoxonase-1 and other factors related to oxidative stress in psoriasis

“…α-Tocopherol is one of four vitamin E forms characterized by the highest biological activity and it is the most common form present in European food products. Tocopherols are synthesized only by photosynthetic organisms and vegetable oils are the richest source of these substances in the diet [14].…”

Nutrient-Based Chemical Library as a Source of Energy Metabolism Modulators

“…On the other hand, there exist a number of pharmaceuticals and functional foods that consist of covalently conjugated multiple nutrients. For example, tocopherol nicotinate, a clinically used lipid antioxidant ( Figure S1A), 1 is a synthetic conjugate of vitamins E and B3. Another example is a conjugate of vitamin C and glucose, AA-2G ( Figure S1B).…”

Vitamin E: Regulatory Role on Signal Transduction

“…Differential competition between lipids and the eight vitamin E analogues at the active site of lipid metabolic enzymes such as phospholipase A2 (PLA2), 5‐, 12‐, and 15‐lipoxygenases (5‐, 12‐, and 15‐LOX, respectively), cyclooxygenase‐2 (COX‐2), and 3‐hydroxy‐3‐methylglutaryl‐coenzyme A (HMG‐CoA) reductase modulates the production of specific messenger lipids such as the inflammatory lipid mediator leukotriene B(4) . Moreover, vitamin E is metabolized and converted into a number of active lipid mediators (e.g., α‐tocopheryl phosphate (αTP), carboxyethylhydroxychromans (CEHC) and long‐chain CEHC precursors, α‐tocopherol quinone/hydroquinone (αTQ/αTHQ), α‐tocopheryl nicotinate) that can have increased and/or additional activities when compared to the non‐converted precursors . In some cases, regulatory effects similar to vitamin E are also mediated by PUFA‐derived lipid mediators, that are protected by vitamin E from oxidation and destruction , thus indirectly contributing to the prevention of diseases in which PUFA are beneficial such as cancer, insulin resistance, inflammation, NASH, and cardiovascular and neurodegenerative diseases .…”