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Cell Aug 2015Advances in neuroscience identified addiction as a chronic brain disease with strong genetic, neurodevelopmental, and sociocultural components. We here discuss the... (Review)
Review
Advances in neuroscience identified addiction as a chronic brain disease with strong genetic, neurodevelopmental, and sociocultural components. We here discuss the circuit- and cell-level mechanisms of this condition and its co-option of pathways regulating reward, self-control, and affect. Drugs of abuse exert their initial reinforcing effects by triggering supraphysiologic surges of dopamine in the nucleus accumbens that activate the direct striatal pathway via D1 receptors and inhibit the indirect striato-cortical pathway via D2 receptors. Repeated drug administration triggers neuroplastic changes in glutamatergic inputs to the striatum and midbrain dopamine neurons, enhancing the brain's reactivity to drug cues, reducing the sensitivity to non-drug rewards, weakening self-regulation, and increasing the sensitivity to stressful stimuli and dysphoria. Drug-induced impairments are long lasting; thus, interventions designed to mitigate or even reverse them would be beneficial for the treatment of addiction.
Topics: Animals; Brain; Choice Behavior; Dopamine; Humans; Neural Pathways; Neuronal Plasticity; Reward; Substance-Related Disorders
PubMed: 26276628
DOI: 10.1016/j.cell.2015.07.046 -
International Journal of Environmental... Apr 2020Substance abuse has been a thorny public health concern throughout human history. Manifestly, prevention and treatment are the two main strategies commonly adopted to...
Substance abuse has been a thorny public health concern throughout human history. Manifestly, prevention and treatment are the two main strategies commonly adopted to tackle the problem of substance abuse. They are in fact cross-disciplinary, and they relate to the various domains of heredity, biology, psychology, cognitive science, family, social development and cultural structures. This special issue, "Substance Abuse, Environment and Public Health," has published empirical studies from different regions and countries globally to enhance the international exchange of latest views and findings on the etiology, processes and influences of substance abuse across different domains, through which a multilevel perspective is considered more helpful for analyzing its complex nature, courses and consequences. This in turn suggests the possible need to employ multiple responses dynamically and integratively in the prevention and treatment of substance abuse.
Topics: Humans; Public Health; Substance-Related Disorders
PubMed: 32290248
DOI: 10.3390/ijerph17072610 -
Neuropharmacology 2009Dopamine is involved in drug reinforcement but its role in addiction is less clear. Here we describe PET imaging studies that investigate dopamine's involvement in drug... (Review)
Review
Dopamine is involved in drug reinforcement but its role in addiction is less clear. Here we describe PET imaging studies that investigate dopamine's involvement in drug abuse in the human brain. In humans the reinforcing effects of drugs are associated with large and fast increases in extracellular dopamine, which mimic those induced by physiological dopamine cell firing but are more intense and protracted. Since dopamine cells fire in response to salient stimuli, supraphysiological activation by drugs is experienced as highly salient (driving attention, arousal, conditioned learning and motivation) and with repeated drug use may raise the thresholds required for dopamine cell activation and signaling. Indeed, imaging studies show that drug abusers have marked decreases in dopamine D2 receptors and in dopamine release. This decrease in dopamine function is associated with reduced regional activity in orbitofrontal cortex (involved in salience attribution; its disruption results in compulsive behaviors), cingulate gyrus (involved in inhibitory control; its disruption results in impulsivity) and dorsolateral prefrontal cortex (involved in executive function; its disruption results in impaired regulation of intentional actions). In parallel, conditioning triggered by drugs leads to enhanced dopamine signaling when exposed to conditioned cues, which then drives the motivation to procure the drug in part by activation of prefrontal and striatal regions. These findings implicate deficits in dopamine activity-inked with prefrontal and striatal deregulation-in the loss of control and compulsive drug intake that results when the addicted person takes the drugs or is exposed to conditioned cues. The decreased dopamine function in addicted individuals also reduces their sensitivity to natural reinforcers. Therapeutic interventions aimed at restoring brain dopaminergic tone and activity of cortical projection regions could improve prefrontal function, enhance inhibitory control and interfere with impulsivity and compulsive drug administration while helping to motivate the addicted person to engage in non-drug related behaviors.
Topics: Animals; Brain; Diagnostic Imaging; Dopamine; Humans; Substance-Related Disorders
PubMed: 18617195
DOI: 10.1016/j.neuropharm.2008.05.022 -
Molecules (Basel, Switzerland) Jun 2023Drug abuse and addiction are major public health concerns, with millions of people worldwide affected by the negative consequences of drug use. To better understand this... (Review)
Review
AIM
Drug abuse and addiction are major public health concerns, with millions of people worldwide affected by the negative consequences of drug use. To better understand this complex issue, a review was conducted to examine the mechanisms of action and effects of drugs of abuse, including their acute and chronic effects, the symptoms of abstinence syndrome, as well as their cardiovascular impacts.
METHODS
The analyzed data were obtained after surveying an electronic database, namely PubMed, with no time limit, grey literature sources, and reference lists of relevant articles.
RESULTS
The review highlights the different categories of drugs of abuse, such as opioids, stimulants, depressants, hallucinogens, and cannabis, and discusses the specific ways that each drug affects the brain and body. Additionally, the review explores the short-term and long-term effects of drug abuse on the body and mind, including changes in brain structure and function, physical health problems, and mental health issues, such as depression and anxiety. In addition, the review explores the effects of drug abuse on cardiovascular health, focusing on electrocardiogram changes. Moreover, the analysis of relevant literature also highlighted possible genetic susceptibility in various addictions. Furthermore, the review delves into the withdrawal symptoms that occur when someone stops using drugs of abuse after a period of chronic use.
CONCLUSION
Overall, this review provides a comprehensive overview of the current state of knowledge on drug abuse and addiction. The findings of this review can inform the development of evidence-based prevention and intervention strategies to address this critical public health issue.
Topics: Humans; Substance-Related Disorders; Substance Withdrawal Syndrome; Hallucinogens; Analgesics, Opioid; Anxiety Disorders
PubMed: 37446631
DOI: 10.3390/molecules28134969 -
Clinical Psychology Review Dec 2018The gender gap in substance use disorders (SUDs), characterized by greater prevalence in men, is narrowing, highlighting the importance of understanding sex and gender... (Review)
Review
The gender gap in substance use disorders (SUDs), characterized by greater prevalence in men, is narrowing, highlighting the importance of understanding sex and gender differences in SUD etiology and maintenance. In this critical review, we provide an overview of sex/gender differences in the biology, epidemiology and treatment of SUDs. Biological sex differences are evident across an array of systems, including brain structure and function, endocrine function, and metabolic function. Gender (i.e., environmentally and socioculturally defined roles for men and women) also contributes to the initiation and course of substance use and SUDs. Adverse medical, psychiatric, and functional consequences associated with SUDs are often more severe in women. However, men and women do not substantively differ with respect to SUD treatment outcomes. Although several trends are beginning to emerge in the literature, findings on sex and gender differences in SUDs are complicated by the interacting contributions of biological and environmental factors. Future research is needed to further elucidate sex and gender differences, especially focusing on hormonal factors in SUD course and treatment outcomes; research translating findings between animal and human models; and gender differences in understudied populations, such as those with co-occurring psychiatric disorders and gender-specific populations, such as pregnant women.
Topics: Female; Humans; Male; Sex Characteristics; Sex Factors; Substance-Related Disorders
PubMed: 29174306
DOI: 10.1016/j.cpr.2017.10.012 -
The Psychiatric Clinics of North America Sep 2022While substance experimentation typically begins in adolescence, substance use disorders (SUDs) usually develop in late teens or early adulthood, often in individuals... (Review)
Review
While substance experimentation typically begins in adolescence, substance use disorders (SUDs) usually develop in late teens or early adulthood, often in individuals who are vulnerable because of biological and socioeconomic risk factors. Severe SUDs-synonymous with addiction-involve changes in limbic and prefrontal brain areas after chronic drug exposure. These changes involve learned associations between drug reward and cues that trigger the anticipation of that reward (known as incentive salience), as well as heightened dysphoria during withdrawal and weakened prefrontal circuits needed for inhibiting habitual responses.
Topics: Adolescent; Adult; Behavior, Addictive; Brain; Humans; Motivation; Reward; Substance-Related Disorders
PubMed: 36055726
DOI: 10.1016/j.psc.2022.05.001 -
Annali Dell'Istituto Superiore Di Sanita 2016A growing body of literature shows that a link exists between substance abuse and stress and that the crosstalk of sex hormones with the neuroendocrine system might... (Review)
Review
A growing body of literature shows that a link exists between substance abuse and stress and that the crosstalk of sex hormones with the neuroendocrine system might differently prime vulnerability to drug addiction in male and female subjects. Thus, understanding the neurobiological mechanisms of addiction and the identification of sex-driven determinants in vulnerability to drug abuse may help to better devise and/or implement strategic (pharmacological, behavioural, social) interventions to prevent or face the issue of addiction. Differences between sexes can be found at all stages of life (in both the animal model and human studies) and may account for genetic, epigenetic and environmental/hormonal factors that in turn affect the functionality of the whole organism leading also to a sex-driven differential vulnerability or resilience to non-communicable pathologies. These include the onset and precipitation of stress-related psychiatric disorders as well as "substance-related and addictive disorders" (as defined in the DSM-V). This paper reviews the scientific literature highlighting significant differences in male and female subjects in stress and neuroendocrine function and the implications for sex-dependent differential vulnerability to drug addiction.
Topics: Animals; Female; Humans; Male; Models, Animal; Sex Characteristics; Sex Factors; Sexual Behavior; Stress, Psychological; Substance-Related Disorders
PubMed: 27364390
DOI: 10.4415/ANN_16_02_07 -
Clinical & Experimental Optometry Jul 2021Illicit drugs and substances of abuse are increasingly used by adults and teenagers, with novel substances constantly becoming available. Many substances can cause... (Review)
Review
Illicit drugs and substances of abuse are increasingly used by adults and teenagers, with novel substances constantly becoming available. Many substances can cause ocular effects or visually threatening conditions. Current literature informing eye-care practitioners on these effects is scant. The present scoping review reports the ocular effects of most commonly used drugs and substances of abuse in the teenage and adult populations of North America. Ovid MEDLINE and Ovid EMBASE databases were searched for publications from 1980 to 2019 regarding ocular effects of drug use. The selected papers regarded human subjects, in either teenage or adult population and included all types of studies, including case reports. Publications in English or in French were included. Exclusion criteria were publications about the use of prescriptions drugs, drug withdrawal, and publications about the use of alcohol, tobacco, or cannabis. Some 241 papers were retained and analysed. The use of various drugs and substances can lead to damage to structures throughout the eye, including but not limited to corneal conditions, glaucoma and other optic neuropathies, maculopathies and endophthalmitis. The data presented in this review may help guide clinicians in their diagnosis and treatment of certain ocular conditions, which could otherwise not be linked to drug use.
Topics: Adolescent; Adult; Endophthalmitis; Eye; Humans; Pharmaceutical Preparations; Retinal Diseases; Substance-Related Disorders
PubMed: 33722158
DOI: 10.1080/08164622.2021.1878852 -
ACS Chemical Neuroscience Sep 2014Neurotransmitter vesicles are known to concentrate hydrogen ions (or protons), the simplest ion, and to release them during neurotransmission. Furthermore, receptors... (Review)
Review
Neurotransmitter vesicles are known to concentrate hydrogen ions (or protons), the simplest ion, and to release them during neurotransmission. Furthermore, receptors highly sensitive to protons, acid-sensing ion channels (ASICs), were previously localized on the opposite side of the synaptic cleft on dendritic spines. Now, recent experiments provide some of the strongest support to date that protons function as a neurotransmitter in mice, crossing synapses onto medium spiny neurons of the nucleus accumbens (NAc), activating ASICs, and ultimately suppressing drug abuse-related behaviors.
Topics: Acid Sensing Ion Channels; Animals; Humans; Mice; Models, Biological; Neurotransmitter Agents; Protons; Substance-Related Disorders; Synaptic Transmission
PubMed: 25054738
DOI: 10.1021/cn500154w -
Clinical Pharmacology and Therapeutics Jan 2012The currently available medications for the treatment of drug abuse have had only limited success. Anti-addiction vaccines, aimed at eliciting antibodies that block the... (Review)
Review
The currently available medications for the treatment of drug abuse have had only limited success. Anti-addiction vaccines, aimed at eliciting antibodies that block the pharmacological effects of drugs, have great potential for treating drug abuse. We review the status of two vaccines that are undergoing clinical trials (for cocaine and nicotine addiction) and two that are still in preclinical development (for methamphetamine and heroin addiction). We also outline the challenges and ethical concerns associated with the development of anti-addiction vaccines and their use as future therapeutics.
Topics: Animals; Behavior, Addictive; Clinical Trials as Topic; Cocaine-Related Disorders; Humans; Substance-Related Disorders; Vaccines
PubMed: 22130115
DOI: 10.1038/clpt.2011.281