Changes in Brain Tissue and Behavior Patterns Induced by Single Short-Term Fasting in Mice

Abstract

In humans, emaciation from long-term dietary deficiencies, such as anorexia, reportedly increases physical activity and brain atrophy. However, the effects of single short-term fasting on brain tissue or behavioral activity patterns remain unclear. To clarify the impact of malnutrition on brain function, we conducted a single short-term fasting study as an anorexia model using male adult mice and determined if changes occurred in migratory behavior as an expression of brain function and in brain tissue structure. Sixteen-week-old C57BL/6J male mice were divided into either the fasted group or the control group. Experiments were conducted in a fixed indoor environment. We examined the effects of fasting on the number of nerve cells, structural changes in the myelin and axon density, and brain atrophy. For behavior observation, the amount of food and water consumed, ingestion time, and the pattern of movement were measured using a time-recording system. The fasted mice showed a significant increase in physical activity and their rhythm of movement was disturbed. Since the brain was in an abnormal state after fasting, mice that were normally active during the night became active regardless of day or night and performed strenuous exercise at a high frequency. The brain weight did not change by a fast, and brain atrophy was not observed. Although no textural change was apparent by fasting, the neuronal neogenesis in the subventricular zone and hippocampus was inhibited, causing disorder of the brain function. A clear association between the suppression of encephalic neuropoiesis and overactivity was not established. However, it is interesting that the results of this study suggest that single short-term fasting has an effect on encephalic neuropoiesis.

Brain More Resistant to Energy Restriction Than Body: A Systematic Review

“…Two thousand eight hundred four works were screened by title or abstract, and 232 articles were analyzed by full text. We identified 13 studies that met all inclusion criteria and focused on how energy restriction affects the central and peripheral energy states (Schärer, 1977 ; Villeneuve et al, 1977 ; Goodman and Ruderman, 1980 ; Harris et al, 1984 ; Ocken and Grunewald, 1988 ; Bodoky et al, 1995 ; Wolff et al, 1999 ; Dubnov et al, 2000 ; Greenberg and Boozer, 2000 ; Ostrowski et al, 2006 ; Peters et al, 2011 ; Hisatomi et al, 2013 ; Ryzhavskii et al, 2019 ).…”

“…Table 1 provides details of the 13 included studies. Eight studies examined rats (Schärer, 1977 ; Villeneuve et al, 1977 ; Goodman and Ruderman, 1980 ; Harris et al, 1984 ; Ocken and Grunewald, 1988 ; Bodoky et al, 1995 ; Greenberg and Boozer, 2000 ; Ryzhavskii et al, 2019 ) and three studies investigated mice (Wolff et al, 1999 ; Dubnov et al, 2000 ; Hisatomi et al, 2013 ). One study was conducted in sand gazelles (Ostrowski et al, 2006 ).…”

“…A considerable spectrum was found: The duration of the calorie restriction ranged from 3 days to 17 months. Three studies used complete food deprivation (Goodman and Ruderman, 1980 ; Bodoky et al, 1995 ; Hisatomi et al, 2013 ), others used an intermittent fasting regimen (Ocken and Grunewald, 1988 ). Food was restricted to about 30–40% (Ostrowski et al, 2006 ; Ryzhavskii et al, 2019 ), to 50% (Villeneuve et al, 1977 ), to 60% (Greenberg and Boozer, 2000 ), and to about 70% of that of controls (Wolff et al, 1999 ).…”

“…The human study bypassed autopsy by measuring organ sizes by magnetic resonance imaging (MRI) (Peters et al, 2011 ). Most studies reported intervention-induced changes in body weight and absolute brain weight (Goodman and Ruderman, 1980 ; Wolff et al, 1999 ; Dubnov et al, 2000 ; Greenberg and Boozer, 2000 ; Peters et al, 2011 ; Hisatomi et al, 2013 ). Four studies additionally reported the relative brain weight (Schärer, 1977 ; Harris et al, 1984 ; Ostrowski et al, 2006 ; Ryzhavskii et al, 2019 ).…”

Changes in bone density and bone quality caused by single fasting for 96 hours in rats

“…Further on, in an experiment in which the C57BL/6J male mice (16 weeks of age) were fasted for 3 days, optical microscopic observation of mouse brain tissues has shown that fasting causes abnormal behavior in mice and suppresses neurogenesis in the hippocampal dentate gyrus and in the subventricular zone. The findings also suggested that fasting inhibits the neuronal neogenesis in the subventricular zone and hippocampus of the brain, causing damage to brain functions (Hisatomi et al, 2013b). As fasting results in changes in the musculoskeletal system and digestive system as well as in other systems, the possibility of irreversible changes in the associated histological structures needs to be considered.…”