OUR R-ALPHA LIPOIC ACID
Benefits žGuaranteed Purity žBetter Absorption žEnhanced
Bioavailability žAntioxidant
Regenerator žMetal Chelation žResearch žClinically
demonstrated effectiveness žPharmaceutical
Manufacturing License žGood Manufacturing
Practices (GMP) In order to be considered a powerful antioxidant, a compound must
meet several criteria. In addition to displaying antioxidant features such as
radical quenching, metal chelation, interaction with other antioxidants,
metabolic regeneration and gene regulation, the substance needs to be
bioavailable and safe. Lipoic acid and
its reduced form, dihydrolipoic acid (DHLA), meet all the above criteria and
therefore may be considered a complete antioxidant. For comparison, vitamin E,
which is regarded as one of the most important biological antioxidants,
scavenges only peroxyl radicals in membranes. R-Alpha-Lipoic Acid is a naturally occurring substance that
offers health benefits beyond plain nutrition. It plays a pivotal role in
cellular metabolism by acting as a coenzyme in energy production and by
functioning as an ideal antioxidant. R-Alpha-Lipoic acid also offers protection against the sequelae
of diabetes, such as neuropathy, cataract, and cardiovascular disease and
ameliorates insulin sensitivity in type II diabetes. In addition, there is
evidence that it delays the aging process, improves brain function and memory,
stimulates immune function and supports liver health. R vs. S Form Conventional chemical synthesis of lipoic acid yields a mixture of
R- and S-enantiomers. Lipoic acid from Alpha Science is processed in such a way
as to yield the active R- isomer only with a purity guaranteed to be higher
than 99%. Bioavailability of R- and S- lipoic acid has been studied
extensively in humans using single dose administration (1,2,3,4,5). After
intravenous administration, there is no difference between R- and S-lipoic acid
concentrations in plasma. However, after oral intake of the combined mixture, a
higher response is found for R-lipoic acid than for the S-form (3). At least
60% higher for the R-form, which is highly significant. Research Recent research has shown that antioxidants function beyond mere
protection from oxidative damage. Oxidants and antioxidants are involved in the
regulation of key mechanisms related to metabolism, immunity, arterial
function, cell proliferation, aging and cell death. Oxidation and reduction
(redox) emerges as the principle underlying mechanism. Thiol antioxidants such
as glutathione and lipoic acid appear to play a predominant role in the
redox-dependent regulation of numerous cellular targets (6). Research has also concluded that antioxidants, namely lipoic acid,
can be of preventive and/or therapeutic benefit for inflammatory
disorders. Lipoic acid plays an
additional role in the regulation of genes related to several pathologies that
include arteriosclerosis, atherosclerosis, arthritis, cancer,
ischemia-reperfusion injury, apoptosis and HIV infection, all involving
inflammation. (7,8,9,10,11). Antioxidant Properties of Lipoic Acid Lipoic acid and its reduced form, DHLA, appear in tissues in free
form indicating that lipoic acid is activated metabolically to DHLA in
vivo. DHLA is a strong reductant that
can regenerate oxidized antioxidants. Specifically, when antioxidants such as
ascorbate, glutathione, coenzyme Q10 and vitamin E scavenge
radicals, they become radicals themselves. DHLA can directly and indirectly
recycle these substances and “reactivate” them (17,18,13,19). From this came
the term “antioxidant network”. For example,
when vitamin E scavenges a peroxyl radical, a vitamin E radical is formed. The
vitamin E radical may be reduced at the lipid/water interface by several
antioxidants, such as ascorbate, ubiquinol, and reduced glutathione (GSH)(see
below). DHLA is able to reduce all these antioxidants and thus regenerate them
and therefore take a central position in the antioxidant network. Remarkably,
lipoic acid has both water-soluble and membrane-soluble characteristics,
enabling it to reduce oxidized antioxidants at the lipid/water interface. The predominant form that interacts with reactive oxygen species
is DHLA, but the oxidized form of lipoic acid can also inactivate free
radicals. The table below lists broad array of reactive oxygen species
scavenged by lipoic acid and DHLA. Table: R-Alpha-Lipoic Acid /Dihydrolipoic Acid (DHLA)—The Most
Versatile Antioxidant Pair
Glutathione Synthesis As mentioned, treatment with lipoic acid enhances glutathione
(GSH) levels in vivo and in vitro (20,21,19,22). Glutathione is the most
important water-soluble endogenous antioxidant and is linked to detoxification
of xenobiotics, modulation of signal transduction, prostaglandin metabolism,
regulation of immune response, control of enzyme activity and peptide hormones,
etc. Studies with human cells have provided insights into how lipoic acid
increases GSH levels. Cysteine
availability is known as the rate-limiting factor in glutathione synthesis.
Lipoic acid is taken up rapidly by the cell and reduced to DHLA, which in turn
reduces cystine to cysteine and accelerates the biosynthesis of GSH (23). Metal Chelation Transition metals such as iron, copper, mercury, or cadmium can
induce free radical damage in biological systems by catalyzing decomposition of
hydroperoxides and generate highly toxic hydroxyl radicals. Lipoic acid and
DHLA may exhibit antioxidant activity by metal chelating (13), which helps
explain the usefulness of lipoic acid for detoxification in heavy metal
poisoning (14,15,16). Recommendations Food intake results in reduced bioavailability of lipoic acid (2).
Therefore, it has been recommended to take up the compound 30 minutes before a
meal or 2 hours afterward. In diabetic
patients gastric emptying is usually delayed. In insulin-dependent diabetics,
delayed gastric emptying had no substantial influence on lipoic acid
bioavailability (12). References:
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