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Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development
Published on: April 15, 2013
Forgotten radicals in biology
Rochette Luc1, Catherine Vergely
1Laboratoire De Physiopathologie Et Pharmacologie Cardiovasculaires Experimentales, Facultes De Medecine Et Pharmacie, Dijon Cedex, France.
International Journal of Biomedical Science : IJBS
|May 16, 2013
Summary
This review explores cellular free radicals, including reactive oxygen and nitrogen species, and their roles in signaling and stress adaptation. It highlights emerging radicals like hydroperoxyl and carbonate radicals, emphasizing their cardiovascular relevance.
Area of Science:
- Biochemistry
- Cellular Biology
- Cardiovascular Physiology
Background:
- Redox reactions are crucial for cellular signaling and stress responses.
- Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are key cellular radicals.
- Cardiovascular pathophysiology involves various signaling molecules and stress adaptation processes.
Purpose of the Study:
- To review established and novel free radicals with potential significance in cardiovascular pathophysiology.
- To discuss the formation and functions of these radicals in cellular homeostasis.
- To highlight the emerging roles of hydrogen disulphide and carbonate radicals.
Main Methods:
- Literature review of existing studies on cellular free radicals.
- Analysis of radical formation pathways and enzymatic involvement (e.g., Cu-Zn SOD).
- Investigation of radical involvement in poly-unsaturated fatty acid (PUFA) isomerization and nucleic acid oxidation.
Main Results:
- Hydroperoxyl radical (HO2•) is a protonated form of superoxide anion (O2•-).
- Hydrogen disulphide (H2S) acts as a signaling molecule and radical source, relevant to cardiovascular functions.
- Carbonate radical participates in Cu-Zn-SOD activity and may oxidize nucleic acids.
Conclusions:
- Cells actively form diverse free radicals, contributing to homeostasis.
- Novel radicals like hydro-sulphide and carbonate radicals have emerging roles in cardiovascular health.
- Understanding these radicals is vital for comprehending cellular redox balance and disease.
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