Bacterial diet affects the age-dependent decline of associative learning in Caenorhabditis elegans
Satoshi Higurashi,
Sachio Tsukada,
Binta Maria Aleogho,
Joo Hyun Park,
Yana Al-Hebri,
Masaru Tanaka,
Shunji Nakano,
Ikue Mori,
Kentaro Noma
Affiliations
Satoshi Higurashi
Milk Science Research Institute, Megmilk Snow Brand Co. Ltd., Saitama, Japan; Group of Nutritional Neuroscience, Neuroscience Institute, Graduate School of Science, Nagoya University, Nagoya, Japan
Sachio Tsukada
Milk Science Research Institute, Megmilk Snow Brand Co. Ltd., Saitama, Japan; Group of Nutritional Neuroscience, Neuroscience Institute, Graduate School of Science, Nagoya University, Nagoya, Japan
Binta Maria Aleogho
Group of Nutritional Neuroscience, Neuroscience Institute, Graduate School of Science, Nagoya University, Nagoya, Japan; Group of Molecular Neurobiology, Neuroscience Institute, Graduate School of Science, Nagoya University, Nagoya, Japan; Group of Microbial Motility, Department of Biological Science, Division of Natural Science, Graduate school of Science, Nagoya University, Nagoya, Japan
Joo Hyun Park
Group of Nutritional Neuroscience, Neuroscience Institute, Graduate School of Science, Nagoya University, Nagoya, Japan
Yana Al-Hebri
Group of Nutritional Neuroscience, Neuroscience Institute, Graduate School of Science, Nagoya University, Nagoya, Japan
Masaru Tanaka
Milk Science Research Institute, Megmilk Snow Brand Co. Ltd., Saitama, Japan; Group of Nutritional Neuroscience, Neuroscience Institute, Graduate School of Science, Nagoya University, Nagoya, Japan
Shunji Nakano
Group of Molecular Neurobiology, Neuroscience Institute, Graduate School of Science, Nagoya University, Nagoya, Japan
Ikue Mori
Group of Molecular Neurobiology, Neuroscience Institute, Graduate School of Science, Nagoya University, Nagoya, Japan
Group of Nutritional Neuroscience, Neuroscience Institute, Graduate School of Science, Nagoya University, Nagoya, Japan; Group of Molecular Neurobiology, Neuroscience Institute, Graduate School of Science, Nagoya University, Nagoya, Japan; Group of Microbial Motility, Department of Biological Science, Division of Natural Science, Graduate school of Science, Nagoya University, Nagoya, Japan
The causality and mechanism of dietary effects on brain aging are still unclear due to the long time scales of aging. The nematode Caenorhabditis elegans has contributed to aging research because of its short lifespan and easy genetic manipulation. When fed the standard laboratory diet, Escherichia coli, C. elegans experiences an age-dependent decline in temperature–food associative learning, called thermotaxis. To address if diet affects this decline, we screened 35 lactic acid bacteria as alternative diet and found that animals maintained high thermotaxis ability when fed a clade of Lactobacilli enriched with heterofermentative bacteria. Among them, Lactobacillus reuteri maintained the thermotaxis of aged animals without affecting their lifespan and motility. The effect of Lb. reuteri depends on the DAF-16 transcription factor functioning in neurons. Furthermore, RNA sequencing analysis revealed that differentially expressed genes between aged animals fed different bacteria were enriched with DAF-16 targets. Our results demonstrate that diet can impact brain aging in a daf-16-dependent manner without changing the lifespan.
