A Novel Fungicidal Action of Silver Nanoparticles: Apoptosis Induction

Silver nanoparticles (nano-Ag) have been known as effective antimicrobial agents with unique properties that improve their biocompatibility because of their high ratio of surface area to volume, no charge, and nontoxicity to humans. Some studies show that nano-Ag interact with membrane or cell wall, DNA, and proteins of microorganisms to produce the antimicrobial effect. Recently, nano-Ag have been reported to exert antimicrobial activity against fungi via different mechanisms known as apoptosis. During apoptosis, the accumulation of intracellular reactive oxygen species plays important regulators in the apoptotic pathway. Subsequently, a series of apoptotic phenotypes such as phosphatidyl serine exposure, cytochrome c release, mitochondrial membrane depolarization, caspase activation, DNA fragmentation, and cell-cycle arrest are shown in the fungal cells. The apoptotic mechanism of nano-Ag will propose an alternative strategy to develop pharmacological agents for pathogens that resist the existing antibiotics.