Brain derived neurotrophic factor (BDNF) has been shown to regulate neuronal development and plasticity and plays a role in learning and memory. Moreover, it is well-established that BDNF plays a role in the hypothalamic pathway that controls body weight and energy homeostasis. Recent evidence identifies BDNF as a player not only in central metabolism, but also in regulating energy metabolism in peripheral organs. Low levels of BDNF are found in patients with neurodegenerative diseases, including Alzheimer's disease and major depression. In addition, BDNF levels are low in obesity and independently so in patients with type 2 diabetes. BDNF is expressed in non-neurogenic tissues, including skeletal muscle and exercise increases BDNF levels not only in the brain and in plasma, but in skeletal muscle as well. BDNF mRNA and protein expression was increased in muscle cells that were electrically stimulated and BDNF increased phosphorylation of AMPK and ACCbeta and enhanced fatty oxidation both in vitro and ex vivo. These data identify BDNF as a contraction-inducible protein in skeletal muscle that is capable of enhancing lipid oxidation in skeletal muscle via activation of AMPK. Thus, BDNF appears to play a role both in neurobiology and in central as well as peripheral metabolism. The finding of low BDNF levels in both neurodegenerative diseases and in type 2 diabetes may explain the clustering of these diseases. BDNF is likely to mediate some of the beneficial effects of exercise with regard to protection against dementia and type 2 diabetes.
Pedersen BK, Pedersen M, Krabbe KS, Bruunsgaard H, Matthews VB, Febbraio MA. ROLE OF EXERCISE-INDUCED BDNF PRODUCTION IN THE REGULATION OF ENERGY HOMEOSTASIS. Exp Physiol. 2009 September University of Copenhagen.