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Hydrogen sulfide as an endogenous modulator in mitochondria and mitochondria dysfunction
Wei Guo1, Jun-tao Kan, Ze-yu Cheng
1Department of Pharmacology, School of Pharmacy, Fudan University, Shanghai 201203, China.
Oxidative Medicine and Cellular Longevity
|January 11, 2013
Summary
Hydrogen sulfide (H2S), once seen as toxic, is now recognized as a vital signaling molecule in mammals. It plays key roles in vascular function, neuronal processes, and offers cytoprotection, especially in mitochondria.
Area of Science:
- Biochemistry
- Physiology
- Neuroscience
Background:
- Hydrogen sulfide (H2S) was traditionally viewed as a toxic industrial gas.
- Recent discoveries reveal H2S is endogenously produced in mammalian tissues from L-cysteine and homocysteine.
- This has shifted the paradigm, highlighting H2S as a crucial physiological signaling molecule.
Purpose of the Study:
- To explore the multifaceted roles of hydrogen sulfide (H2S) in mammalian physiology and pathology.
- To investigate H2S's involvement as a gaseous messenger in cardiovascular and neurological functions.
- To understand the cytoprotective effects of H2S, particularly within mitochondria.
Main Methods:
- Enzymatic assays to detect H2S production from precursors.
- Physiological studies examining H2S effects on vascular relaxation and angiogenesis.
- Electrophysiological recordings to assess H2S modulation of NMDA receptor activity and long-term potentiation.
- Mitochondrial studies to evaluate H2S's impact on cytoprotection.
Main Results:
- H2S is confirmed as an endogenous signaling molecule with diverse physiological roles.
- Demonstrated involvement of H2S in vascular relaxation, angiogenesis, and ion channel function.
- Evidence shows H2S enhances NMDA receptor responses and facilitates hippocampal long-term potentiation.
- Physiological H2S concentrations exhibit significant cytoprotective effects in mitochondria.
Conclusions:
- Hydrogen sulfide (H2S) is a critical endogenous neuromodulator and physiological messenger.
- H2S plays protective roles in conditions like ischemia/reperfusion injury and heart damage.
- Further research into H2S signaling pathways is warranted for therapeutic applications in neurological and cardiovascular diseases.
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