Lipoic Acid: Its Antioxidant and Anti-Inflammatory Role and Clinical Applications

Abstract

Lipoic acid (LA) is an antioxidant able to produce its effects in aqueous or lipophilic environments. Lipoate is the conjugate base of lipoic acid, and the most prevalent form of LA under physiological conditions. It presents a highly negative reduction potential, increases the expression of antioxidant enzymes and participates in the recycling of vitamins C and E. Due to these properties, LA is called the "universal antioxidant". LA is also involved with anti-inflammatory action, independently of its antioxidant activity. This review was carried out, aiming to identify, analyze, and rationalize the various clinical, physiopathological and/or physiological situations in which LA, through oral supplementation, was tested on human and animal (rats and mice) models. LA was mainly tested in cardiovascular diseases (CVD), obesity, pain, inflammatory diseases and aging. LA uses in CVD and obesity, in humans, are controversial. On the other hand, beneficial effects on inflammation and pain were observed. LA supplementation in animal models may prolong life, has neuroprotective effects and presents positive effects against cancer. Differences observed in human and animal models can be due, in part, to different treatments (LA combined with other antioxidants, different doses) and to the variety of biomarkers investigated in animal experiments. These results suggest the need for further clinical trials to guide health professionals regarding the safety of prescription of this supplement.

Integrated transcriptomic and proteomic analyses reveal ɑ‐lipoic acid‐regulated cell proliferation via Grb2‐mediated signalling in hepatic cancer cells

“…ɑ‐LA and its reduced form, dihydrolipoic acid (DHLA), are direct scavengers of free radicals and act indirectly as metal chelators, thereby lessening free‐radical damage. Moreover, ɑ‐LA not only is important to the function of some crucial enzymes that feed carbon into the tricarboxylic acid cycle but also generates dynamic regulatory information about the metabolic status of the mitochondrial matrix, ultimately functioning to control metabolic fluxes 6, 7. A study by German physicians noted reduced levels of ɑ‐LA in the serum of patients with cirrhosis, diabetes mellitus and polyneuropathy as early as the 1960s 8, 9.…”

Usefulness of Α-Lipoc Acid, Leucoselect and Ginkgoselect Phytosoma in Chronic Venous Insufficiency

“…In a previous study Leucoselect ® Phytosome ® has been proven able to reduce oxidative stress [4] while some reports suggested a protective effect of α-Lipoic acid on endothelial cell damage [5] and antioxidant proprieties [6]. In particular, the alpha-lipoic acid plays cytoprotective action against free radicals [6,11], especially protecting the nerves in the case of induced degeneration (itching / paresthesia symptomatology). The leucocianidine (Leucoselect) shows an activity of reducing vascular permeability, savings of vitamin E, chelation of iron and copper, inhibition of protease (hyaluronidase, collagenase, elastase).…”

“…The α-Lipoic acid is a cofactor essential to the functioning of all the dehydrogenase of the human body. Some reports suggested a protective effect of α-Lipoic acid on endothelial cell damage [5] and antioxidant proprieties [6]. In the same fashion, Ginkgo biloba extract derivatives have been shown as vascular protective agents to attenuate oxidative stress damage [7].…”

Cytokine Regulation of Regenerative Processes in Pancreatic Gland in Alloxan-Induced Diabetic Rats, and It Correction by 1,3,4-Thiadiazine Composition and Lipoic Acid

“…Липоевая кислота успешно применяется в терапии осложнений СД как препарат, корри-гирующий метаболические нарушения, инсу-линорезистентность, гиперпродукцию провос-палительных цитокинов клетками иммунной системы, что было доказано на различных моде-лях экспериментальной патологии [34]. Данный факт определил выбор липоевой кислоты в каче-стве препарата сравнения в настоящем экспери-ментальном исследовании.…”