Plasma Level of Brain Derived Neurotrophic Factor in a sample of Egyptian Chronic Heroin Users; Impact on Cognitive Functions

Abstract

The present study is a cross sectional comparative study that investigates the impact of chronic heroin use on cognitive functions and its relation to BDNF plasma level in a sample of 50 male Egyptianchronic Heroin users compared to 38 healthy volunteer. Substance use is a hydrophobic disorder that preys youth starting from their early adolescent period leading to grievous consequences on their entire life including negative effect on their brain tissues and subsequently cognitive functions which then brings harmful social, mental, physical, familial and economic consequences. Moreover substance use disorder is a wide spread phenomenon. In Egypt, one of the studies that was done in five districts to estimate the percentage of substance use showed results as follow: 14,8% polysubstance use, 26% THC use, 9% opioid use, 10% alcohol use, 7% sedative hypnotics use and 0.5 % stimulants use -reported in The National Review of Drug Abuse and Addiction- so in a glance we can find out to what extend substance use resemble a real problem in our country It is now clear that substance use disorder is a chronic relapsing disease, and the tendency to relapse are caused by a combination of environmental, biological, and genetic factors, where processes during early stages of drug use is suggested to promote strong maladaptive connections between use of drugs and environmental input that serves the future cravings and drug-seeking behaviors. These neuroadaptations have been extensively examined in order to clarify mechanisms underlying the development and maintenance of addiction, to find strategies for relevant treatment. Results from neurobiological studies demonstrated that neuronal activity in the mesocorticolimbic dopamine system mediates drug reward and relapse to drug seeking, this dopamine system composed of cell bodies in ventral tegmental area (VTA) that project to several brain areas, including the medial prefrontal cortex (mPFC), nucleus accumbens (NA), amygdala, bed nucleus of striaterminalis (BNST) and hippocampus. The hippocampus is an area included in the limbic structures that is of particular interest, as it was found to be essential for several aspects related to the addictive process.