Substance use disorders (SUDs) represent a significant clinical and social problem. In the United States, recent decades have been marked by an increasing prevalence of alcohol use disorder (AUD) and opioid use disorder (OUD). ~14% of adults currently meet the criteria for AUD, and ~29% had met AUD criteria at least once during their lifetime. The annual cost of AUD and alcohol-related disorders is approximately $250 billion, and the prevalence of AUD continues to rise. Similarly, the prevalence of OUD in the United States has reached epidemic proportions, with the costs exceeding $1 trillion.
Despite such a socioeconomic burden, current pharmacological options for SUDs remain relatively inefficient. Thus, AUD is treated with either disulfiram, naltrexone, or acamprosate. OUD is approached with opioid replacement therapy or naltrexone. In the settings of addiction to stimulants or hallucinogens, treatment is mainly supportive. It is possible that the absence/inefficacy of existing treatment modalities is a consequence of insufficient mechanistic insight into the development and progression of SUDs. Pharmacologically, current medications
are based on relatively simplistic concepts. In the case of AUD, for example, naltrexone is used as it may function as a non-selective antagonist of opioid receptors capable of reducing the alcohol-induced release of dopamine in the nucleus accumbens and limiting the pleasure after alcohol consumption. Although some efficacy of naltrexone was shown in randomized controlled trials, its actual clinical benefits are very low, which is not surprising given that the etiopathogenetic mechanisms of AUD might be enormously complex. Recent years showed that AUD may be associated with a broad dysregulation of genetic and transcriptional mechanisms. For instance, a large DNA methylation
epigenome-wide association study employed a cross-tissue/cross-phenotypic approach and showed that AUD is associated with a network of differentially methylated regions. Another study demonstrated that AUD is associated with genome-wide changes in splicing in multiple brain regions.
The goal of this Research Topic is to highlight genome-wide molecular mechanisms of SUDs using the paradigm of systems biology. Of interest would be studies related to commonly abused substances (such as alcohol, benzodiazepines, opioids, cocaine, amphetamines, cannabis, etc.). Of particular relevance would be investigations that delineate genetic underpinnings of addiction, studies focusing on epigenetic and transcriptional changes (with the use of high-throughput approaches such as microarrays, RNA sequencing, etc.), and proteomics studies. Even though genome-wide mechanisms are likely to be the focus, research characterizing novel specific pathways involved in addiction would be of interest as well. Since -omics studies in the field of SUDs are in a pre-clinical phase, we expect that most manuscripts will be based on data from animal models or/and in vitro experiments, with the implementation of bioinformatics techniques and computational biology (although findings from human subjects would also be welcome, as such datasets would strengthen a translational potential).
In sum, we look forward to studies that would provide insight into genome-wide mechanisms of SUDs and suggest novel therapeutic targets using concepts of systems biology and personalized medicine.
Substance use disorders (SUDs) represent a significant clinical and social problem. In the United States, recent decades have been marked by an increasing prevalence of alcohol use disorder (AUD) and opioid use disorder (OUD). ~14% of adults currently meet the criteria for AUD, and ~29% had met AUD criteria at least once during their lifetime. The annual cost of AUD and alcohol-related disorders is approximately $250 billion, and the prevalence of AUD continues to rise. Similarly, the prevalence of OUD in the United States has reached epidemic proportions, with the costs exceeding $1 trillion.
Despite such a socioeconomic burden, current pharmacological options for SUDs remain relatively inefficient. Thus, AUD is treated with either disulfiram, naltrexone, or acamprosate. OUD is approached with opioid replacement therapy or naltrexone. In the settings of addiction to stimulants or hallucinogens, treatment is mainly supportive. It is possible that the absence/inefficacy of existing treatment modalities is a consequence of insufficient mechanistic insight into the development and progression of SUDs. Pharmacologically, current medications
are based on relatively simplistic concepts. In the case of AUD, for example, naltrexone is used as it may function as a non-selective antagonist of opioid receptors capable of reducing the alcohol-induced release of dopamine in the nucleus accumbens and limiting the pleasure after alcohol consumption. Although some efficacy of naltrexone was shown in randomized controlled trials, its actual clinical benefits are very low, which is not surprising given that the etiopathogenetic mechanisms of AUD might be enormously complex. Recent years showed that AUD may be associated with a broad dysregulation of genetic and transcriptional mechanisms. For instance, a large DNA methylation
epigenome-wide association study employed a cross-tissue/cross-phenotypic approach and showed that AUD is associated with a network of differentially methylated regions. Another study demonstrated that AUD is associated with genome-wide changes in splicing in multiple brain regions.
The goal of this Research Topic is to highlight genome-wide molecular mechanisms of SUDs using the paradigm of systems biology. Of interest would be studies related to commonly abused substances (such as alcohol, benzodiazepines, opioids, cocaine, amphetamines, cannabis, etc.). Of particular relevance would be investigations that delineate genetic underpinnings of addiction, studies focusing on epigenetic and transcriptional changes (with the use of high-throughput approaches such as microarrays, RNA sequencing, etc.), and proteomics studies. Even though genome-wide mechanisms are likely to be the focus, research characterizing novel specific pathways involved in addiction would be of interest as well. Since -omics studies in the field of SUDs are in a pre-clinical phase, we expect that most manuscripts will be based on data from animal models or/and in vitro experiments, with the implementation of bioinformatics techniques and computational biology (although findings from human subjects would also be welcome, as such datasets would strengthen a translational potential).
In sum, we look forward to studies that would provide insight into genome-wide mechanisms of SUDs and suggest novel therapeutic targets using concepts of systems biology and personalized medicine.
