American Society of Hirudotherapy

SGS Compound Reference

Complete bioactive component database for medicinal leech SGS

Last Updated: March 5, 2026Reviewed by: Andrei Dokukin, MD

Last updated: March 14, 2026

Medicinal leech SGSry gland secretion (SGS) contains over 100 identified bioactive compounds. The table below summarizes the major pharmacologically active components with their molecular properties, biological targets, and pharmaceutical derivatives. This reference is derived from the comprehensive analysis of Baskova (2004) and subsequent molecular characterization studies.

Major SGS Components

CompoundMW (Da)TargetFunctionPharma Derivative
Hirudin~7,000Thrombin (active site + exosite I)Most potent natural thrombin inhibitor (Ki ~10⁻¹⁵ M)Lepirudin, Desirudin, Bivalirudin
Calin~65,000Collagen-vWF bindingInhibits collagen-mediated platelet aggregation; prolongs bleeding
Destabilase~12,300Cross-linked fibrin (ε-lysyl-γ-glutamyl bonds)Thrombolytic; neurotrophic at 10⁻¹² MUnder investigation
Eglins b/c~8,100Neutrophil elastase, cathepsin GAnti-inflammatory (potato inhibitor I family)Recombinant eglins studied
Bdellins A/B~6,200-6,500Trypsin, plasmin, acrosinAnti-inflammatory; prevents premature fibrinolysis
LDTI~4,700Mast cell tryptaseAnti-allergic; anti-inflammatory (Kazal-type inhibitor)Under investigation
Hyaluronidase~27,500Hyaluronic acid in ECM"Spreading factor" — facilitates SGS penetration into tissuesHylenex (recombinant)
Antistasin~15,000Factor XaAnticoagulant; antistasin superfamily founderInspired factor Xa inhibitor class
Ghilanten~14,000Factor XIIIaInhibits fibrin cross-linking (synergizes with destabilase)
Decorsin~4,400GPIIb/IIIa integrinRGD peptide; potent platelet aggregation inhibitorRGD peptide research
Ornatin~5,700GPIIb/IIIa integrinRGD peptide from H. placibdellaRGD peptide research
LCI~6,800Carboxypeptidase APrevents removal of C-terminal lysines from fibrin (modulates fibrinolysis)
C1s InhibitorVariableComplement C1sClassical complement pathway inhibition
ApyraseVariableADPHydrolyzes ADP; inhibits ADP-mediated platelet aggregation
CollagenaseVariableCollagenECM degradation; tissue penetration
Histamine-likeLow MWHistamine receptorsVasodilation; increases local blood flow to bite site
AnestheticLow MWNociceptorsLocal analgesia at bite site (onset 1-2 min)

Functional Categories

Anticoagulant

Hirudin (thrombin), antistasin (factor Xa), LCI (carboxypeptidase A), ghilanten (factor XIIIa). Multi-target cascade inhibition at 4+ points.

Antiplatelet

Calin (collagen-vWF), decorsin/ornatin (GPIIb/IIIa), apyrase (ADP). Three independent antiplatelet mechanisms.

Thrombolytic

Destabilase (cross-linked fibrin). Unique isopeptidase activity cleaving ε-lysyl-γ-glutamyl bonds in stabilized fibrin.

Anti-Inflammatory

Eglins (elastase, cathepsin G), bdellins (trypsin, plasmin), LDTI (mast cell tryptase), C1s inhibitor (complement).

Tissue Penetration

Hyaluronidase (ECM), collagenase (collagen), histamine-like compounds (vasodilation). Enable SGS components to reach systemic circulation.

Neurotrophic

Destabilase, bdellins, eglins. Neurite outgrowth stimulation in chick embryo ganglia. Destabilase active at 10⁻¹² M.

Pharmaceutical Legacy

FDA-Approved Drugs Derived from Leech Biology

DrugSGS OriginFDA YearIndication
Bivalirudin (Angiomax)Hirudin C-terminal peptide2000PCI anticoagulation
Desirudin (Iprivask)Recombinant hirudin2003DVT prophylaxis
Dabigatran (Pradaxa)Hirudin SAR research2010Stroke prevention in AF

Related Resources

This website provides educational information and does not constitute medical advice, diagnosis, or treatment recommendations. Medicinal leech therapy carries clinically meaningful risks and should be performed only by qualified clinicians under institutionally approved protocols. FDA 510(k) clearance for medicinal leeches is limited to specific indications; investigational and off-label discussions are labeled accordingly. For patient-specific guidance, consult a qualified healthcare provider.