Peptide - Rejuvenate Clinic

Peptides are short chains of amino acids linked by peptide bonds. Typically peptides contain less than 50 amino acids. Anything larger is considered a protein. Peptides play several important roles in the human body:

• Signal transduction - Peptides act as signaling molecules between cells to regulate bodily functions. For example, insulin is a peptide hormone that regulates blood sugar levels.
• Immune defense - Antimicrobial peptides are an essential part of the innate immune system, defending the body against bacteria, viruses, and fungi.
• Bioactive agents - Many peptides have biological activity and are used as medicines. For instance, the peptide drug Liraglutide is used to treat diabetes.

How are peptides formed? Peptides are synthesized when the carboxyl group of one amino acid forms an amide bond with the amino group of another amino acid. This reaction results in a peptide bond and a water molecule as a byproduct. The amino acids in a peptide are linked together in a specific sequence determined by the mRNA template. Key features of peptides:

• Short chain of 2 to 50 amino acids
• Bonded by peptide (amide) bonds
• Synthesized by ribosomes directly from mRNA
• Often lack complex secondary or tertiary structure
• Water-soluble
• Often rapidly degraded

In terms of structure, peptides are intermediate between single amino acids and full-length proteins. While lacking the complexity of most proteins, some peptides can form simple secondary structures like α-helices and β-sheets. However, they do not fold into complex 3D shapes with catalytic capabilities like enzymes. What are some examples of peptides? Here are a few biologically important peptide examples:

• Oxytocin - this neuropeptide acts as both a hormone and neurotransmitter. It plays a role in social bonding, childbirth, and lactation.
• Glutathione - functions as an antioxidant, preventing damage to cells by reactive oxygen species.
• Morphine - an opiate peptide that acts on the central nervous system to relieve pain.

In summary, peptides are short chains of amino acids that play diverse biological roles related to cell signaling, immunity, and medicine. As smaller and simpler versions of proteins, peptides have their own unique structural properties and functions in the body. Understanding the biology of peptides may lead to new therapeutic discoveries and drug development opportunities.