Nerve growth factor, stress and diseases

Stress is a constant threat for homeostasis and is represented by different extrinsic and intrinsic stimuli (stressors, Hans Selye's 'noxious agents'), such as aggressive behavior, fear, diseases, physical activity, drugs, surgical injury, and environmental and physiological changes. Our organism responds to stress activating the adaptive stress system to activate compensatory responses for restoring homeostasis. Nerve Growth Factor (NGF) was discovered as a signaling molecule involved in survival, protection, differentiation, and proliferation of sympathetic and peripheral sensory neurons. NGF mediates stress with an important role in translating environmental stimuli into physiological and pathological feedbacks since NGF levels undergo important variations after exposure to stressful events. Psychological stress, lifestyle stress, and oxidative stress are well known to increase the risk of mental disorders such as schizophrenia, major depressive disorders, bipolar disorder, alcohol use disorders and metabolic disorders such as metabolic syndrome. This review reports recent works describing the activity of NGF in mental and metabolic disorders related to stress.