SPEAKER: Gary Lewin
Department of Neuroscience, Max-Delbrück Center for Molecular Medicine
TITLE: “Extremeophile mammals and pain“
The naked mole-rat (Heterocephalus glaber) is famous for its longevity and unusual physiology. This eusocial species that lives in highly ordered and hierarchical colonies with a single breeding queen, 20 million years ago also discovered secrets enabling resistance to specific types of pain . Unlike most mammals, naked mole-rats do not feel the burn of chili pepper’s active ingredient, capsaicin, nor the sting of acid. Indeed, by accumulating mutations in genes encoding proteins that are only now being exploited as targets for new pain therapies (the nerve growth factor receptor TrkA and voltage-gated sodium channel, NaV1.7), this species mastered the art of analgesia before humans evolved. Recently, we have identified pain-insensitivity as a trait shared by several closely related African mole-rat species. One of these African mole-rats, the Highveld mole-rat (Cryptomys hottentotus pretoriae) is uniquely completely impervious and pain free when confronted with electrophilic compounds that activate the TRPA1 ion channel. In summary, it is striking how evolution has consistently selected genes that play critical roles in pain. It appears likely that still more mechanisms useful for pain therapy remain to be discovered in the evolutionary record.