The Master Compendium of Peptide Therapy: Expanded Classifications and Benefits

Peptide therapy leverages highly specialized amino acid sequences to regulate complex biological pathways, spanning metabolic health, tissue regeneration, cognitive enhancement, and cellular longevity. [1, 2]

As clinical research expands, the number of distinct therapeutic peptides used in functional medicine has grown significantly. To provide a truly exhaustive overview, the chart below expands on the primary categories, introducing specific secondary and advanced cellular signaling agents.


Expanded Quick Reference: Advanced Peptide Classifications

CategoryPeptide NamePrimary Biological Function & Health BenefitsSourcing & Clinical Notes
Growth Hormone Secretagogues (GHS)Sermorelin
Ipamorelin
CJC-1295
Tesamorelin
• Mimics growth hormone-releasing hormone (GHRH)
• Stimulates natural pituitary growth hormone release
• Reduces visceral adipose tissue (specifically abdominal fat)
• Enhances slow-wave deep sleep patterns and cellular recovery
Administered via subcutaneous injection. Tesamorelin is specifically FDA-approved for abdominal fat accumulation.
Tissue Repair & Structural MechanicsBPC-157
TB-500
KPV
• Accelerates angiogenesis (new blood vessel growth)
• Repairs systemic mucosal layers (gut lining/leaky gut)
• Soft-tissue, ligament, and tendon remodeling
• Powerful anti-inflammatory via downregulating mast cells
Often paired together synergistically. Highly scrutinized by athletic organizations; banned by WADA for competitive athletes.
Metabolic Health & Incretin MimicsSemaglutide
Tirzepatide
AOD-9604
MOTS-c
• Delays gastric emptying and increases satiety
• Elevates mitochondrial energy and insulin sensitivity
• Stimulates lipolysis (fat breakdown) without affecting blood sugar
Semaglutide and Tirzepatide are mainstream, FDA-approved medications for type 2 diabetes and chronic obesity.
Cognitive Optimization & NootropicsSemax
Selank
Dihexa
• Boosts Brain-Derived Neurotrophic Factor (BDNF)
• Modulates serotonin, dopamine, and GABAergic systems
• Functions as a non-sedative anxiolytic to calm central stress
• Under study for reversing neurodegeneration
Often delivered as nasal sprays or subcutaneous injections to cross the blood-brain barrier effectively.
Cellular Longevity & Circadian ControlEpitalon
DSIP
• Activates telomerase to protect cellular structures
• Regulates pineal gland melatonin production
• Induces restorative delta-wave deep sleep cycles
• Dampens acute cortisol spikes from nervous system stress
Epitalon is heavily researched in Eastern European clinical medicine for anti-aging and sleep restoration.
Immunomodulation & DefenseThymosin Alpha-1• Promotes T-cell and natural killer (NK) cell maturation
• Regulates adaptive and innate immune functions
• Eradicates chronic low-grade viral or bacterial loads
Derived natively from the thymus gland; widely utilized as an adjunct treatment for infectious diseases.
Dermatological & Collagen RejuvenationGHK-Cu
Matrixyl
Argireline
• Triggers localized type I and type III collagen synthesis
• Softens deep wrinkles by interrupting muscle contraction signals
• Repairs the epidermal barrier and neutralizes free radicals
Available as high-potency Allies of Skin Multi Peptides Serum formulas or targeted microneedling topicals.
Systemic & Sexual WellnessPT-141
Oxytocin
• Activates central nervous system melanocortin receptors
• Treats hypoactive sexual desire disorder (HSDD)
• Modulates social bonding, empathy, and acute stress relief
PT-141 (Bremelanotide) acts entirely via the nervous system, bypassing the cardiovascular system.

Technical Deep-Dive: How Advanced Peptides Operate

Mitochondrial vs. Pituitary Signaling

Peptides are broadly split by their cellular destination. Pituitary peptides (like Ipamorelin or Sermorelin) travel directly to endocrine receptors to instruct the release of natural growth factors. [1, 2, 3]

Conversely, mitochondrial peptides like MOTS-c act within the cell’s power plants. They turn on metabolic switches like AMPK, forcing the body to process carbohydrates and fats exactly as it would during intense aerobic exercise—even while at rest. [1, 2]

The Systemic Inflammation Control Loop

Peptides like KPV and BPC-157 manage the body’s master inflammatory pathways. Rather than merely masking pain, they actively block the production of pro-inflammatory cytokines while encouraging fibroblasts to lay down brand-new extracellular tissue. This structural reinforcement is why functional medicine clinics often use them to treat complex gut conditions like Ulcerative Colitis or Crohn’s alongside severe tendon damage.