Isolated from the venom of the marine cone snail, genus Conus, Conotoxins (CTX), or called Conopeptide is a group of neurotoxic peptides. Conotoxin peptides comprise 10-30 amino acid residues, usually with one or more disulfide bonds.
There are five known conotoxins whose activities have been determined: α(alpha)-, δ(delta)-, κ(kappa)-, μ(mu)-, and ω(omega)- types. Each of the five categories of conotoxins targets a unique target:
α-conotoxin suppresses nicotinic acetylcholine receptors in nerves and muscles.
δ-conotoxin suppresses the rapid inactivation of voltage-dependent sodium channels.
κ-conotoxin suppresses potassium channels.
μ-conotoxin suppresses muscle voltage-dependent sodium channels.
ω-conotoxin suppresses voltage-dependent N-type calcium channels.
Over the past, conotoxin and its associated ion channels have been studied to understand the toxic impact of poisoning on the human body. More recently, attention has been given to the use of conotoxins in medicinal therapies and cosmetics.
Conotoxins in Pain Management
The originally discovered pharmaceutical potential has been in cases of intractable pain. ω-conotoxin has an analgesic impact: the effect of ω-conotoxin M VII A is 100 to 1000 times that of morphine. Currently, a syntheticω-conotoxin from C. magus is approved by the U.S. Food and Drug Administration for the treatment of pain under the trade name Prialt. The active ingredient in Prialt is ω-conotoxin MVIIA (or ziconotide), which is probably the best known of the conotoxins discovered to date.
Conotoxins in Other Diseases
Apart from the clinical development of ω-MVIIA, other conotoxins have been studied to treat Parkinson's disease, epilepsy, heart disease and diabetes. Conotoxins have the potential to treat a wide group of diseases due to their broad range of neuromodulatory targets.
Like botulinum toxin (Botox), the conotoxins have myorelaxant properties and can be formulated as an anti-wrinkle cream or injection. One such conotoxin is μ-CIIIC, which, as part of the European Commission-funded CONCO project, was originally separated from the fish-hunting cone snail Conus consors. The skeletal muscle sodium channel, Nav1.4, and the neuronal sodium channel Nav1.2 are preferentially inhibited by μ-CIIIC. And because of this inhibition, Nav1.4 can act as a myorelaxant. Initially, μ-CIIIC was developed as a drug to treat pain and as a local anesthetic which is now sold under the name “XEP™-018” as the active ingredient in a non-prescription cosmetic anti-wrinkle product.
As an alternative to chemical synthesis, recombinant DNA and synthetic biology technologies have been explored for the biosynthesis of conotoxins (conopeptides).
We are developing Recombinant Conopeptide/ Conotoxin as an active substance or active pharmaceutical ingredient (API). The product is coming to market soon.