Lipoic Acid as a Possible Pharmacological Source of Hydrogen Sulfide/Sulfane Sulfur

Abstract

The aim of the present study was to verify whether lipoic acid (LA) itself is a source of H2S and sulfane sulfur. It was investigated in vitro non-enzymatically and enzymatically (in the presence of rat tissue homogenate). The results indicate that both H2S and sulfane sulfur are formed from LA non-enzymatically in the presence of environmental light. These results suggest that H2S is the first product of non-enzymatic light-dependent decomposition of LA that is, probably, next oxidized to sulfane sulfur-containing compound(s). The study performed in the presence of rat liver and kidney homogenate revealed an increase of H2S level in samples containing LA and its reduced form dihydrolipoic acid (DHLA). It was accompanied by a decrease in sulfane sulfur level. It seems that, in these conditions, DHLA acts as a reducing agent that releases H2S from an endogenous pool of sulfane sulfur compounds present in tissues. Simultaneously, it means that exogenous LA cannot be a direct donor of H2S/sulfane sulfur in animal tissues. The present study is an initial approach to the question whether LA itself is a donor of H2S/sulfane sulfur.

Comparative Study to Evaluate the Efficacy of Hydrogen Sulfide Separately or in Combination with some Antioxidants against myocardial dysfunction in Irradiated Rats

“…These data may be due to the pharmadynamics and pharmakinetics properties of ALA which produces H2S in its catabolism. These data are in harmony with those obtained by Bilska-Wilkosz et al [50]. The last authors indicated that H2S is formed from ALA in the presence of environmental light.…”

International Union of Basic and Clinical Pharmacology. CII: Pharmacological Modulation of H2S Levels: H2S Donors and H2S Biosynthesis Inhibitors

“…It should be mentioned that 3-MP, in addition to acting as a substrate of 3-MST, can also produce H 2 S spontaneously (i.e., in solution, in the absence of any cellular components or enzymes) (Coletta et al, 2015). Moreover, lipoic acid, in addition to being a cofactor of the 3-MST reaction, has also been shown recently to release H 2 S nonenzymatically (Bilska-Wilkosz et al, 2017). These actions should be considered when interpreting the pharmacological effects of 3-MST, especially when substrates or cofactors are used at higher (micromolar) concentrations.…”

Manniophyton fulvum extract attenuates sodium nitroprusside induced oxidative stress in wistar rats

“…7 These compounds exhibit intriguing biological properties such as antimicrobial, antioxidant and anti-inflammatory. 2 [17][18][19][20] The metabolism of the drug has been widely studied both in experimental animals and humans as classical inductor of oxidative stress. 21,22 From the study, the group administered with SNP only showed significant increase in MDA concentration while rhodanese and GSH activity showed significant decrease compared to the control which may be attributed to the decomposition of SNP.…”

“…It has been reported that nearly one billion of the world's population suffer from high blood pressure. [1][2] Sodium nitroprusside (SNP) is an antihypertensive agent used continuously in hypertensive emergencies. It decomposes into its metabolites that are pharmacologically inactive but induces toxicity within minutes of administration.…”