In a new study, published online in Nature, the researchers used the newly deciphered atomic structure of the brain's "morphine receptor" to custom-engineer a novel drug candidate that blocked pain as effectively as morphine in mouse experiments, but did not share the potentially deadly side effects typical of opioid drugs. In particular, the new drug did not interfere with breathing, the main cause of death in overdoses of prescription painkillers as well as street narcotics like heroin, or cause constipation, another common opioid side effect. The new drug also appears to side-step the brain's dopamine-driven addiction circuitry and did not cause drug-seeking behavior in mice.
More work is needed to establish that the newly formulated compound is truly non-addictive and to confirm that it is as safe and effective in humans as it is in rodents, the authors say. But if the findings are borne out, they could transform the fight against the ongoing epidemic of prescription painkiller addiction.
Key to the new paper was knowing the atomic structure of the mu-opioid receptor, the brain's "morphine receptor", said Dr Brian Shoichet, a professor of pharmaceutical chemistry in UCSF's School of Pharmacy and co-senior author.
In a two-week period, the researchers performed roughly four trillion "virtual experiments", simulating how millions of different candidate drugs could turn and twist in millions of different angles to find those configurations that were most likely to fit into a pocket on the receptor and activate it.
Pharm.D @ SRIPMS-CBE-TN