[Ag(I)(Et(2)PCH(2)CH(2)PPh(2))(2)]NO(3): An Antimitochondrial Silver Complex

Area of Science:

• Inorganic Chemistry
• Biochemistry
• Mitochondrial Biology

Background:

• Mitochondria are crucial organelles involved in cellular respiration and energy production.
• Mitochondrial dysfunction is implicated in various diseases.
• Developing targeted agents for mitochondria is a key area of research.

Purpose of the Study:

• To synthesize and characterize a novel silver(I) complex, [Ag(eppe)(2)]NO(3).
• To investigate the antimitochondrial activity and selectivity of the silver(I) complex.
• To explore potential therapeutic applications by examining the complex's effects on yeast growth and mitochondrial mutations.

Main Methods:

• X-ray crystallography was used to determine the structure of the silver(I) complex.
• Antimitochondrial activity was assessed by measuring inhibition of yeast growth in non-fermentable media.
• The induction of the mitochondrial mutation 'petite' was evaluated.
• Stability studies were conducted in cell culture media and in the presence of glutathione.
• Reactivity with biological molecules like glutathione disulfides and serum albumin was examined.

Main Results:

• The silver(I) complex [Ag(eppe)(2)]NO(3) exhibits a tetrahedral geometry with specific Ag-P bond lengths.
• The complex demonstrates selective antimitochondrial activity, inhibiting yeast growth at low concentrations (2.5 μM).
• It induces the mitochondrial 'petite' mutation, an effect partially reversed by aspirin.
• The complex is stable in cell culture media and glutathione but reacts with oxidized glutathione and serum albumin.
• Gold(I) complexes with similar ligands ([Au(eppe)(2)]Cl and [Au(dppe)(2)]Cl) lacked mitochondrial selectivity.

Conclusions:

• The silver(I) complex [Ag(eppe)(2)]NO(3) is a potent, mitochondrially targeted agent with potential for further investigation.
• Its ability to inhibit yeast growth and induce mitochondrial mutations highlights its antimitochondrial properties.
• The differential reactivity with biological thiols and disulfides warrants further study.
• The lack of mitochondrial selectivity in analogous gold complexes underscores the specific activity of the silver complex.