Impaired lysosomal acidification triggers iron deficiency and inflammation in vivo
King Faisal Yambire,
Christine Rostosky,
Takashi Watanabe,
David Pacheu-Grau,
Sylvia Torres-Odio,
Angela Sanchez-Guerrero,
Ola Senderovich,
Esther G Meyron-Holtz,
Ira Milosevic,
Jens Frahm,
A Phillip West,
Nuno Raimundo
Affiliations
King Faisal Yambire
Institute of Cellular Biochemistry, University Medical Center Goettingen, Goettingen, Germany
Christine Rostosky
European Neuroscience Institute, a Joint Initiative of the Max-Planck Institute and of the University Medical Center Goettingen, Goettingen, Germany
Takashi Watanabe
Biomedizinische NMR, Max-Planck Institute for Biophysical Chemistry, Goettingen, Germany
David Pacheu-Grau
Institute of Cellular Biochemistry, University Medical Center Goettingen, Goettingen, Germany
Sylvia Torres-Odio
Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Austin, United States
Angela Sanchez-Guerrero
Institute of Cellular Biochemistry, University Medical Center Goettingen, Goettingen, Germany; European Neuroscience Institute, a Joint Initiative of the Max-Planck Institute and of the University Medical Center Goettingen, Goettingen, Germany
Ola Senderovich
Faculty of Biotechnology and Food Engineering, Technion Israel Institute of Technology, Haifa, Israel
Esther G Meyron-Holtz
Faculty of Biotechnology and Food Engineering, Technion Israel Institute of Technology, Haifa, Israel
Lysosomal acidification is a key feature of healthy cells. Inability to maintain lysosomal acidic pH is associated with aging and neurodegenerative diseases. However, the mechanisms elicited by impaired lysosomal acidification remain poorly understood. We show here that inhibition of lysosomal acidification triggers cellular iron deficiency, which results in impaired mitochondrial function and non-apoptotic cell death. These effects are recovered by supplying iron via a lysosome-independent pathway. Notably, iron deficiency is sufficient to trigger inflammatory signaling in cultured primary neurons. Using a mouse model of impaired lysosomal acidification, we observed a robust iron deficiency response in the brain, verified by in vivo magnetic resonance imaging. Furthermore, the brains of these mice present a pervasive inflammatory signature associated with instability of mitochondrial DNA (mtDNA), both corrected by supplementation of the mice diet with iron. Our results highlight a novel mechanism linking impaired lysosomal acidification, mitochondrial malfunction and inflammation in vivo.
