Hydrogen Sulfide as a "Double-Faced" Compound: One with Pro- and Antioxidant Effect

Area of Science:

• Biochemistry
• Molecular Biology
• Physiology

Background:

• Hydrogen sulfide (H2S) is a gasotransmitter involved in cellular signaling.
• H2S concentration changes are linked to oxidative stress in various diseases.
• Gasotransmitters like nitric oxide (NO•) and carbon monoxide (CO) share signaling roles with H2S.

Purpose of the Study:

• To explore the dual role of hydrogen sulfide (H2S) as both an antioxidant and prooxidant in biological systems.
• To elucidate the mechanisms underlying H2S's antioxidant effects, particularly its interaction with glutathione.
• To discuss the interactions between H2S and key reactive oxygen species (ROS) and reactive nitrogen species (RNS).

Main Methods:

• Literature review and theoretical discussion on H2S biological functions.
• Analysis of H2S interactions with reactive oxygen species (ROS) such as superoxide radical anion (O2•−) and hydrogen peroxide (H2O2).
• Examination of H2S interactions with reactive nitrogen species (RNS) like peroxynitrite anion (ONOO−).

Main Results:

• H2S exhibits a "double face" in biological systems, acting as both an antioxidant and a prooxidant.
• H2S may exert antioxidant effects by modulating the concentration of the key antioxidant, glutathione.
• H2S directly interacts with various ROS and RNS, influencing cellular redox balance.

Conclusions:

• Hydrogen sulfide plays a complex role in regulating oxidative stress.
• Understanding H2S's dual antioxidant and prooxidant activities is crucial for comprehending its physiological and pathological significance.
• Further research into H2S interactions with ROS/RNS and glutathione modulation is warranted.