Anabolismus

Anabolismus, in English commonly referred to as anabolism, denotes the set of metabolic processes that construct complex molecules from smaller building blocks, requiring an input of energy. It contrasts with catabolismus (catabolism), which breaks down larger molecules to release energy. Anabolismus occurs in nearly all living cells and underpins growth, tissue repair, and the storage of energy in macromolecules.

Major anabolic pathways include protein synthesis from amino acids, nucleic acid synthesis from nucleotide precursors, carbohydrate storage through glycogen or starch synthesis, lipid synthesis including fatty acids and triglycerides, and the assembly of structural polymers and membranes. These processes typically consume energy carriers such as ATP and reducing equivalents like NADPH, and are coordinated with cellular energy and nutrient status.

Regulation: Anabolic activity is controlled by hormonal and intracellular signaling networks that sense energy and nutrient availability. Hormones such as insulin, insulin-like growth factor 1, growth hormone, and androgens promote protein and glycogen synthesis, whereas fasting and glucocorticoids tend to suppress anabolic flux. Central regulatory pathways include mTOR, which promotes growth when energy and nutrients are ample, and AMPK, which inhibits anabolic processes during energy stress. Availability of substrates, cofactors, and redox balance also modulates the rate of anabolic reactions.

Clinical and lifestyle relevance: Adequate nutrition and hormonal balance support normal anabolic function, essential for growth, wound healing, and maintenance of body tissues. Imbalances can affect metabolic health, aging, and recovery from injury or illness.