Mole-rats may help identify arthritis drug

WASHINGTON, Dec. 16 (UPI) -- The insensitivity of naked mole-rats to acid-induced pain could lead to better treatments for humans suffering from inflammatory arthritis, U.S. scientists say.

Found in sub-Saharan Africa, the rats live deep in huge colonies in underground tunnels, with very little oxygen and high levels of carbon dioxide.

"Exposure to high levels of carbon dioxide in turn would evoke acidosis, but the naked mole-rat has evolved in a way to manage this acid load and to be able to live in acidic environments, which for most other rodents in the world would be uninhabitable," neuroscientist Ewan St. John Smith, the lead author of the study, told CNN.

Inflammatory disorders such as arthritis are normally associated with acidosis, scientists say.

Pain-sensing neurons in mole-rats contain proteins with genetic mutations that prevent neurons from firing off pain signals in response to acid, the study, published in Science, said.

"If a drug could now be developed which acts on these particular proteins on the sensory neurons, you could limit the ability of acid to cause pain in patients with arthritis and other inflammatory disorders," Smith said.