Abstract We recently identified physical exercise as a newly defined inducer of autophagy in vivo. Exercise induced autophagy in multiple organs involved in metabolic regulation, such as muscle, liver, pancreas and adipose tissue. To study the physiological role of...
Abstract Disruption of autophagy--a key homeostatic process in which cytosolic components are degraded and recycled through lysosomes--can cause neurodegeneration in tissue culture and in vivo. Upregulation of this pathway may be neuroprotective, and much effort is...
Abstract Ghrelin is a gut/brain hormone with a unique acyl modification and various biological functions in fish and mammals. In addition to its possible role as a circulating orexigenic factor, ghrelin has been shown to regulate several other physiological processes...
Abstract Fasting is characterized by increased whole body lipolysis and lipid oxidation, decreased glucose oxidation and insulin resistance. To identify the regional sources and underlying mechanisms, we studied 10 healthy male volunteers post-absorptively and after...
The metabolic patterns of the brain, muscle, adipose tissue, kidney, and liver are strikingly different. Let us consider how these organs differ in their use of fuels to meet their energy needs: 1. Brain. Glucose is virtually the sole fuel for the human brain, except...
Abstract Stable isotope tracers and indirect calorimetry were used to evaluate the progressive alterations in lipid and glucose metabolism after 12, 18, 24, 30, 42, 54, and 72 h of fasting in six healthy male volunteers. The rates of appearance (Ra) of glycerol and...
Abstract Serum GH concentrations are increased in fasted or malnourished human subjects. We investigated the dynamic mechanisms underlying this phenomenon in nine normal men by analyzing serum GH concentrations measured in blood obtained at 5-min intervals over 24 h...
Abstract Background: The declining activity of the growth hormone--insulin-like growth factor I (IGF-I) axis with advancing age may contribute to the decrease in lean body mass and the increase in mass of adipose tissue that occur with aging. Methods: To test this...