Drug Withdrawal Leads to Brain Dysfunction

An animal model of drug addiction shows that ‘cold turkey’ withdrawal leads to a decline in brain function, according to a recent study.

It is well known that opioids promote the expression of pro-inflammatory cytokines (which act to promote cell death) in the central nervous system, but recent in vitro evidence has illuminated an opposing mechanism: opioid-induced release of neuroprotective chemokines (which act to promote cell life). Scientists at Georgetown University Medical Centre set out to examine the effects of chronic morphine treatment and withdrawal on the expression of pro-inflammatory and neuroprotective proteins in mice.

The findings, published in Brain, Behaviour, and Immunity show that chronic morphine exposure in mice increases secretion of a specific neuroprotective chemokine and decreases the release of pro-inflammatory cytokines, whereas withdrawal of the opioid has the opposite effect. Therefore, researchers have suggested that drug withdrawal promotes neuronal death and inhibits neuronal growth and protection.

This study has allowed scientists to recognise the action of opioids and their signalling cascades that contribute to both pathological and healthy brain states. These findings may have vast implications for clinical treatment of drug addiction, as sudden withdrawal has now been implicated in mental decline.

Original article at: http://www.sciencedirect.com/science/article/pii/S0889159113004170