Consumption of the synthetic drug MDPV - a powerful psychostimulant known as 'cannibal drug'- in adolescence, can increase vulnerability of cocaine addiction during adulthood, according to a study carried out with laboratory animals and led by the researchers Elena Escubedo, from the Faculty of Pharmacy and Food Sciences and the Institute of Biomedicine of the UB (IBUB) and Olga Valverde, head of the Neurobiology of Behaviour Research Group (GreNeC) of Pompeu Fabra University (UPF).

Cocaine addiction is now a great social, economic and health problem in lots of countries around the world. Therefore, any factor stimulating the effects of its consumption should be considered, and this is the aim of the new study, carried out on mice and published in the journal British Journal of Pharmacology. Other authors of this study are the experts David Pubill, Jordi Camarasa, Raúl López-Arnau and Letícia Duart, from the Research Group Neuropsicofarmacologia dels Derivats Amfetamínics (Neuropsychopharmacology of Amphetamine Derivatives) of the UB, and Miguel Àngel Luján, from the Neurobiology of Behaviour Research Group (UPF).

A new design drug with effects similar to those of cocaine

Design drugs are a new generation of addictive substances which have become popular among youngsters. Methylenedioxpyrovalrone (MDPV) is an amphetamine derivative spread as a high-abuse substance with higher psychostimulant effects than those of cocaine. Regarding the effects of this drug on humans, which inhibit the collection of neurotransmitters dopamine and noradrenaline, there is no scientific bibliography yet.

The new study analyses the influence of MDPV consumption during adolescence and its impact on adults' vulnerability in cocaine use. The breaking point reference of the experts was the similarity of MPDPV and cocaine action mechanisms, and the practically permanent effects created by these addictive substances in certain brain areas - mostly in the nucleus accumbens- and pattern response alterations when facing specific stimuli.

In the research, adolescent mice were treated with MDPV during seven days. After three weeks without the substance, adult animals' sensitivity to cocaine was analyzed under different experimental protocols. At the same time, the changes in certain proteins associated to the addictive process were also analyzed.

"In the new study, we state that the animals treated with MDPV during adolescence show reinforcing behavior patterns to cocaine which are higher than the control group. Also, these behavioural changes are related to alterations of factor expression directly related to addiction. For instance, the level of the factor DeltaFosB is three times higher than the normal level and it stays high during the three weeks after removing the addictive substances from the animals", says Professor Elena Escubedo, also member of the Research Group Neuropsicofarmacologia dels Derivats Amfetamínics (Neuropsychopharmacology of Amphetamine Derivatives) of the UB.

DeltaFosB, in particular, is a transcription factor involved in neuroplasticity expressed in addictions. "Since this factor is understood as a molecular "power switch" for cocaine addiction, we think this is the essential molecule to explain a great part of this phenomenon" says Escubedo.

According to Professor Olga Valverde, from the Department of Experimental and Health Sciences of the Pompeu Fabra University, "although drug use can lead to addiction at any age, the new research shows that the sooner someone starts taking drugs, the more likely s/he will develop future severe problems. Therefore, efforts have to be focused on the study of consequences of exposure to the main abusive drugs during adolescence".

Article: Exposure of mice to MDPV during adolescence increases the psychostimulant, rewarding and reinforcing effects of cocaine in adulthood, R. López-Arnau, M.A. Luján, L. Duart-Castells, D. Pubill, J. Camarasa, O. Valverde, E. Escubedo, British Journal of Pharmacology, doi: 10.1111/bph.13771, published online 6 March 2017.