Temperature affects longevity and age‐related locomotor and cognitive decay in the short‐lived fish Nothobranchius furzeri

Summary Temperature variations are known to modulate aging and life‐history traits in poikilotherms as different as worms, flies and fish. In invertebrates, temperature affects lifespan by modulating the slope of age‐dependent acceleration in death rate, which is thought to reflect the rate of age‐related damage accumulation. Here, we studied the effects of temperature on aging kinetics, aging‐related behavioural deficits, and age‐associated histological markers of senescence in the short‐lived fish Nothobranchius furzeri. This species shows a maximum captive lifespan of only 3 months, which is tied with acceleration in growth and expression of aging biomarkers. These biological peculiarities make it a very convenient animal model for testing the effects of experimental manipulations on life‐history traits in vertebrates. Here, we show that (i) lowering temperature from 25 °C to 22 °C increases both median and maximum lifespan; (ii) life extension is due to reduction in the slope of the age‐dependent acceleration in death rate; (iii) lowering temperature from 25 °C to 22 °C retards the onset of age‐related locomotor and learning deficits; and (iv) lowering temperature from 25 °C to 22 °C reduces the accumulation of the age‐related marker lipofuscin. We conclude that lowering water temperature is a simple experimental manipulation which retards the rate of age‐related damage accumulation in this short‐lived species.