Isovaline is a rare amino acid transported to earth by the Murchison meteorite, which landed in

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

in 1969. The discovery of isovaline in the biosphere demonstrates an extraterrestrial origin of amino acids and has been linked to the homochirality of life on earth suggesting a role in the origin of life. The structure of isovaline is similar to the amino acids GABA and glycine, the chief inhibitory neurotransmitters in the mammalian central nervous system. Isovaline acts as an analgesic in mice by activating peripheral GABA_B receptors. In a mouse model of osteoarthritis isovaline restored mobility, suggesting inhibition of nociception by isovaline in the synovial membrane of the mouse knee. Isovaline does not cross the

blood–brain barrier The blood–brain barrier (BBB) is a highly selective semipermeable membrane, semipermeable border of endothelium, endothelial cells that prevents solutes in the circulating blood from ''non-selectively'' crossing into the extracellular fluid of ...

and does not enter into the brain or spinal cord. Drugs such as

opioids Opioids are substances that act on opioid receptors to produce morphine-like effects. Medically they are primarily used for pain relief, including anesthesia. Other medical uses include suppression of diarrhea, replacement therapy for opioid use ...

cross the blood–brain barrier to produce analgesia but often produce in addition confusion, sedation, and addiction. Isovaline acts downstream to the cyclooxygenase system that NSAIDs inhibit, suggesting a means to avoid adverse effects such as irritation of the gastrointestinal system.

References

{{GABAergics Amino acids Analgesics GABAB receptor agonists Peripherally selective drugs

See also

References