Biological Properties

Alpha lipoic acid (ALA) is one of the most potent biological antioxidants known. Referred to as the “universal” antioxidant, ALA is unique among anti-oxidants, demonstrating anti-oxidant activity in aqueous, as well as in lipophilic regions, and in extracellular and intracellular environments. Also unique among anti-oxidants, ALA participates in the recycling of other important endogenous anti-oxidants such as vitamins E and C, ubiquinone and glutathione.

The primary role of antioxidants is to act as scavengers of free radical molecules, inactivating various reactive oxygen species (hydroxyl radicals, nitric oxide radical, peroxynitrite, hydrogen peroxide, hypochlorite, singlet oxygen, and peroxyl radicals). Oxygen-derived free radicals can damage DNA, proteins and lipids, resulting in inflammation and acute and delayed cell death. The body protects itself from the harmful effects of free radicals and other oxidants through multiple anti-oxidant enzyme systems such as superoxide dismutases (SOD), peroxidases, and through natural antioxidant molecules such as glutathione. When too many free radicals are produced for the body’s normal defenses to convert, “oxidative stress” occurs with a cumulative result of reduced cellular function, and ultimately, disease.

The damage that occurs in many liver diseases is often linked to the production of free radicals. The membranes that surround cells and organelles are composed of long chain fatty acids (lipids), that are subject to the process of lipid peroxidation. Free radicals play a major role in cell membrane damage, cause proteins and DNA to cross-link, and interfere with ribosomal protein production.

Since oxidative stress is observed in peripheral blood mononuclear cells from hepatitis C patients, it is hypothesized that oxidative stress might alter lymphocyte function and facilitate the chronicity of the infection. It also appears that the hepatitis C virus codes for a selenium-dependent glutathione peroxidase enzyme, by linking viral replication and pathogenesis to the selenium status and dietary oxidant/antioxidant balance of the host. This phenomenon could help explain why hepatitis C disease progression is accelerated by oxidant stresses such as alcoholism and iron overload.

Primary among the many biological actions of alpha lipoic acid are the chelation of heavy metals, the quenching of various free radical species, and the recycling of vitamins E, vitamin C and glutathione, making it a uniquely important compound in counteracting oxidative stress associated with various liver conditions.
