Metabolic Pathways
Mechanisms of energy sensing, glucose handling, lipid transport, and cellular growth.
Energy Sensing
Every cell needs a way to know when fuel is running low, and AMP-activated protein kinase is the gauge that reads it. When energy stores fall and the cell's ratio of spent to charged fuel molecules climbs, this enzyme switches on within minutes, throttling the expensive business of building new molecules and flipping the cell toward burning fat and recycling its own worn-out parts. Roughly a dozen downstream targets translate that single signal into a coordinated shift in metabolism, which is why the same sensor sits at the center of how exercise, calorie restriction, and metformin all appear to act. When the gauge stays responsive, cells clear damaged components and tolerate stress better. A sluggish version of it tracks with the metabolic decline that accompanies aging, making it one of the most studied dials in longevity science.
One-Carbon Metabolism
The one-carbon metabolism pathway encompasses the folate cycle and methionine cycle, providing methyl groups for DNA methylation and other critical processes.