Categories of Peptides

Quick Learn…

Human peptides can be broadly categorized into several major groups based on their functions and roles in the body. Some of the major groupings include:

1. Hormones:
   • Endocrine Hormones: Released into the bloodstream to regulate distant target organs, e.g., insulin, growth hormone.
   • Neurotransmitters: Act as chemical messengers in the nervous system, e.g., serotonin, dopamine.
2. Enzymes:
   • Digestive Enzymes: Facilitate the breakdown of food, e.g., amylase, lipase.
   • Metabolic Enzymes: Regulate cellular processes, e.g., catalase, ATPase.
3. Antimicrobial Peptides (AMPs):
   • Defensins: Help defend against pathogens by disrupting their cell membranes.
   • Cathelicidins: Exhibit antimicrobial activity against bacteria, viruses, and fungi.
4. Structural Proteins:
   • Collagen: Provides strength and structure to connective tissues.
   • Elastin: Imparts elasticity to tissues like skin and blood vessels.
5. Neuropeptides:
   • Opioid Peptides: Regulate pain and mood, e.g., endorphins, enkephalins.
   • Hypothalamic Peptides: Control various physiological processes, e.g., oxytocin, vasopressin.
6. Cell Signaling Peptides:
   • Growth Factors: Stimulate cell growth and differentiation, e.g., insulin-like growth factor (IGF), epidermal growth factor (EGF).
   • Cytokines: Regulate immune responses and inflammation, e.g., interleukins, tumor necrosis factor (TNF).
7. Transport Peptides:
   • Hemoglobin: Transports oxygen in red blood cells.
   • Ferritin: Stores and transports iron in the body.
8. Homeostatic Peptides:
   • Regulatory Peptides: Maintain balance in physiological processes, e.g., ghrelin (appetite regulation), leptin (energy balance).

These categories represent a diverse range of peptides that play crucial roles in the regulation and maintenance of various physiological functions in the human body.