Cell fasting: Cellular response and application of serum starvation

  Humans suffer transient or persistent starvation due to a lack of food intake, either because of fasting, voluntary dieting, or due to the scarcity of available food. At the cellular level it is possible to possess pathological starvation during ischemia and solid tumors. Blood provides many nutrients to our cells, and researchers provide these nutrients to cells in culture in the form of enriched culture medium plus serum from animal sources. In response to starvation, animals use hormonal cues to mobilize stored resources to provide nutrients to individual cells. Besides whole-body responses to nutrient deprivation, individual cells sense and react to lack of nutrients. At the cellular level, starvation triggers different responses such as cell cycle arrest and apoptosis. Stop cycling for proliferating cells is the primary response to nutrient deprivation. Under certain conditions, the cell reacts to nutrient deprivation by engaging the mitochondrial pathway of apoptosis. Thus, serum starvation is regarded as a procedure to prepare cells for an experiment in serum-free conditions such as induction cell cycle synchronization. Several researchers have used serum starvation as a tool to study molecular mechanisms involved in different cellular process, metabolic researches and evaluation of a drug effect.