Fasting interventions, which involve alternating periods of fasting and refeeding, are generally thought to improve health. But these interventions don't work as well in old animals. The question is: Why? By studying the short-lived killifish, researchers have shown that older fish deviate from a youthful fasting and refeeding cycle, and instead enter a state of perpetual fasting, even when ingesting food. However, the benefits of refeeding after fasting in old killifish can be restored by genetically activating a specific subunit of AMP kinase, an important sensor of cellular energy. These mutant fish experienced improved health and longevity, indicating that both fasting and refeeding are needed to confer health benefits and act through AMP kinase to do so.
Read more …Cycle of fasting and feeding is crucial for healthy aging
A surprising thing happened when researchers began exploring whether early-life stress compounds the effects of a childhood head injury on health and behavior later in life: In an animal study, stress changed the activation level of many more genes in the brain than were changed by a bump to the head.
Read more …Early-life stress changes more genes in brain than a head injury
Though people often want to share good news as soon as they learn it, a study has found that keeping good news a secret before telling someone else could make people feel more energized and alive.
Read more …When keeping secrets could brighten your day