Research & Education

And Yet Another Role for Alpha-Lipoic Acid

 

Not too long ago we posted a blog on alpha-lipoic acid in regards to improving complications of type 2 diabetes. This nutrient is also helpful for chelating heavy metals and owing to its capacity for recycling glutathione and vitamins C and E it’s been called “an antioxidant of antioxidants.” But alpha-lipoic acid (ALA) doesn’t stop there. This workhorse compound may also be beneficial for skin health.

The powerful antioxidant effects of ALA make it an active ingredient in cosmetic products intended to protect the skin from photoaging. A small study (n=33 women mean age 54 years) in which subjects applied a 5% lipoic acid-containing cream to half their face and a placebo cream to the other half twice daily for 12 weeks the skin on the treatment side showed statistically significant improvements in four methods of assessment: self-evaluation by the subjects clinical evaluation photographic evaluation and laser profilometry. Laser profilometry was the most objective method and it showed an average decrease in skin roughness of 50.8% (44.9-54.0) on the ALA-treated half compared with 40.7% (32.4-48.7) on the placebo-treated half of the face (P < 0.001).

Some of the signs of aging skin are a result of decreased collagen synthesis. The beneficial effects of ALA on the appearance of skin are generally assumed to result from this compound’s antioxidant properties. And while that likely plays an important role there’s more to ALA here. An in vitro study showed that ALA enhances the biosynthesis of new collagen in normal human dermal fibroblasts (NHDFs). ALA increased the synthesis and deposition of type I collagen in these cells and “facilitated the expression of a collagen-processing enzyme prolyl-4-hydroxylase pointing to the existence of a posttranslational mechanism among the LA-mediated effects on collagen synthesis.”

Aside from sun damage smoking is a major cause of skin damage. A mouse study in which mice were exposed to the effects of 12 cigarettes per day for 8 weeks showed that compared to a group that did not receive ALA the group that was treated with ALA at 100 mg/kg showed reductions in damage to collagen bundles hair follicle degradation and reduction sweat gland degeneration and mononuclear cell infiltration into the dermis. Malondialdehyde an indicator of lipid peroxidation and protein carbonylation—a marker for oxidative stress—were both significantly lower in the ALA-treated group than in the untreated group.

Alpha lipoic acid may also be helpful for individuals affected by atopic dermatitis. In a mouse model of this painful and aesthetically unpleasing condition oral administration of ALA inhibited increases of epidermal thickness in induced atopic dermatitis-like skin lesions and “significantly suppressed production of interferon (IFN)-γ and interleukin (IL)-4 by activated CD4(+) T cells.” Additionally topical application of a formula containing ALA dramatically reduced serum IgE which is a key player in type I hypersensitivity reactions (including atopic dermatitis but also allergic rhinitis sinusitis and select food allergies.)

Another painful condition that reduces quality of life is scleroderma (systemic sclerosis). Here too alpha-lipoic acid may be helpful. Lipoic acid and its reduced form dihydrolipoic acid (DHLA) are produced by lipoic acid synthetase (LIAS). ALA content and LIAS activity were shown to be lower in fibroblasts from patients with scleroderma than in cells from subjects without the condition. DHLA was shown to reverse the pro-fibrotic phenotype of these cells by modulating several signaling pathways that contribute to tissue fibrosis and vascular abnormalities. 

Finally topical ALA may be helpful for wound healing after physical trauma. Application of topical ALA was shown to accelerate healing from a surgical wound in rats. Seven days after the surgery rats treated with ALA were 60.7% healed (± 8.4%) compared to 43.0% (± 17.4%) in the control group that underwent surgery but received no ALA treatment.

The richest food sources of alpha-lipoic acid are hardworking organs such as heart liver and kidney. Maybe this is a reason to bring offal back into your diet. If you can’t quite fathom chewing on a mouthful of heart or liver sneak it into meatloaf or chili. You won’t even know it’s there!