Chapter 8: Production and Signaling of Methane
Published:27 Jun 2018
Methanogenesis has been associated exclusively with anoxic environments and the activity of prokaryotes, but there is convincing evidence for alternative pathways of biological methane formation in the aerobic biosphere, including plants, fungi, algae, and animals. Once generated by anaerobe microbes or released by a non-archaeal process, methane is widely considered to be biologically inactive. However, apart from the data on the effects of endogenously generated methane, several studies have reported that exogenous methane influences the key regulatory mechanisms and cellular pathways involved in oxidative and nitrosative stress responses in antigen-dependent and antigen-independent models of inflammation. This chapter reviews the available literature on methane-producing processes in eukaryotes and the interactions of methane with other biological gases, and summarizes the most relevant results that establish the bioactive role of methane in eukaryotic biological systems. These data collectively imply that methane liberation and effectiveness in eukaryotes are both linked to hypoxic events and redox regulation, and support the notion that methane plays important signaling roles in the mammalian physiology and pathophysiology.