Roles of Hostility and Depression in the Association between the MAOA Gene Polymorphism and Internet Gaming Disorder

A synonymous mutation of rs1137070 cause the mice Maoa gene transcription and translation to decrease

The Monoamine Oxidase-A (MAOA) EcoRV polymorphism (rs1137070) is a unique synonymous mutation (c.1409 T > C) within the MAOA gene, which plays a crucial role in Maoa gene expression and function. This study aimed to explore the relationship between the mouse Maoa rs1137070 genotype and differences in MAOA gene expression. Mice carrying the CC genotype of rs1137070 exhibited a significantly lower Maoa expression level, with an odds ratio of 2.44 compared to the T carriers. Moreover, the wild-type TT genotype of MAOA demonstrated elevated mRNA expression and a longer half-life. We also delved into the significant expression and structural disparities among genotypes. Furthermore, it was evident that different aspartic acid synonymous codons within Maoa influenced both MAOA expression and enzyme activity, highlighting the association between rs1137070 and MAOA. To substantiate these findings, a dual-luciferase reporter assay confirmed that GAC was more efficient than GAT binding. Conversely, the synonymous mutation altered Maoa gene expression in individual mice. An RNA pull-down assay suggested that this alteration could impact the interaction with RNA-binding proteins. In summary, our results illustrate that synonymous mutations can indeed regulate the downregulation of gene expression, leading to changes in MAOA function and their potential association with neurological-related diseases.

Biomarkers of Internet Gaming Disorder-A Narrative Review

Since game mechanics and their visual aspects have become more and more addictive, there is concern about the growing prevalence of Internet gaming disorder (IGD). In the current narrative review, we searched PubMed and Google Scholar databases for the keywords "igd biomarker gaming" and terms related to biomarker modalities. The biomarkers we found are grouped into several categories based on a measurement method and are discussed in the light of theoretical addiction models (tripartite neurocognitive model, I-PACE). Both theories point to gaming-related problems with salience and inhibition. The first dysfunction makes an individual more susceptible to game stimuli (raised reward seeking), and the second negatively impacts resistance to these stimuli (decreased cognitive control). The IGD patients' hypersensitivity to reward manifests mostly in ventral striatum (VS) measurements. However, there is also empirical support for a ventral-to-dorsal striatal shift and transition from goal-directed to habitual behaviors. The deficits in executive control are demonstrated in parameters related to the prefrontal cortex (PFC), especially the dorsolateral prefrontal cortex (DLPFC). In general, the connection of PFC with reward under cortex nuclei seems to be dysregulated. Other biomarkers include reduced P3 amplitudes, high-frequency heart rate variability (HRV), and the number of eye blinks and saccadic eye movements during the non-resting state. A few studies propose a diagnostic (multimodal) model of IGD. The current review also comments on inconsistencies in findings in the nucleus accumbens (NAcc), anterior cingulate cortex (ACC), and precuneus and makes suggestions for future IGD studies.

Neurobiological risk factors for problematic social media use as a specific form of Internet addiction: A narrative review

Problematic social media use (PSMU) is a behavioral addiction, a specific form of problematic Internet use associated with the uncontrolled use of social networks. It is typical mostly for modern adolescents and young adults, which are the first generations fully grown up in the era of total digitalization of society. The modern biopsychosocial model of the formation of behavioral addictions, postulating the impact of a large number of biological, psychological, and social factors on addictive behavior formation, may be quite applicable to PSMU. In this narrative review, we discussed neurobiological risk factors for Internet addiction with a focus on current evidence on the association between PSMU and structural/ functional characteristics of the brain and autonomic nervous system, neurochemical correlations, and genetic features. A review of the literature shows that the vast majority of the mentioned neurobiological studies were focused on computer games addiction and generalized Internet addiction (without taking into account the consumed content). Even though a certain number of neuroimaging studies have been conducted for PSMU, there is practically no research on neuropeptide and genetic associations for PSMU to date. This fact points to the extremely high relevance of such studies.

The relationship between positive youth development and internet gaming disorder in Chinese adolescents: A moderated mediation model

Internet gaming disorder (IGD) is a social problem that cannot be ignored. Considerable research has shown that IGD can impede the healthy physical and mental development of adolescents. Based on positive youth development theory and stage-environment fit theory, the current study explored the mediating effect of depression and the moderating effect of gender to determine the association between positive youth development (PYD) and IGD. A sample of 1970 Chinese adolescents aged 11-18 years (1021 boys, 940 girls, and 10 unidentifiable individuals) completed questionnaires related to PYD, depression, IGD, and their background information. The results revealed that PYD negatively predicted IGD. After controlling for gender and age, this study found that depression mediated the relationship between PYD and IGD. Furthermore, gender moderated the relationship between depression and IGD. Boys with depressive symptoms were more likely to indulge in IGD than girls. This research contributes to a more thorough understanding of how PYD decreases the risk of IGD. These findings suggest that cultivating PYD attributes is a promising approach to prevent or reduce depression and IGD among adolescents in mainland China.

Advances in problematic usage of the internet research - A narrative review by experts from the European network for problematic usage of the internet

Global concern about problematic usage of the internet (PUI), and its public health and societal costs, continues to grow, sharpened in focus under the privations of the COVID-19 pandemic. This narrative review reports the expert opinions of members of the largest international network of researchers on PUI in the framework of the European Cooperation in Science and Technology (COST) Action (CA 16207), on the scientific progress made and the critical knowledge gaps remaining to be filled as the term of the Action reaches its conclusion. A key advance has been achieving consensus on the clinical definition of various forms of PUI. Based on the overarching public health principles of protecting individuals and the public from harm and promoting the highest attainable standard of health, the World Health Organisation has introduced several new structured diagnoses into the ICD-11, including gambling disorder, gaming disorder, compulsive sexual behaviour disorder, and other unspecified or specified disorders due to addictive behaviours, alongside naming online activity as a diagnostic specifier. These definitions provide for the first time a sound platform for developing systematic networked research into various forms of PUI at global scale. Progress has also been made in areas such as refining and simplifying some of the available assessment instruments, clarifying the underpinning brain-based and social determinants, and building more empirically based etiological models, as a basis for therapeutic intervention, alongside public engagement initiatives. However, important gaps in our knowledge remain to be tackled. Principal among these include a better understanding of the course and evolution of the PUI-related problems, across different age groups, genders and other specific vulnerable groups, reliable methods for early identification of individuals at risk (before PUI becomes disordered), efficacious preventative and therapeutic interventions and ethical health and social policy changes that adequately safeguard human digital rights. The paper concludes with recommendations for achievable research goals, based on longitudinal analysis of a large multinational cohort co-designed with public stakeholders.

Effects of MAO-B inhibitors on non-motor symptoms and quality of life in Parkinson's disease: A systematic review

Non-motor symptoms (NMS) are common among patients with Parkinson's disease and reduce patients' quality of life (QOL). However, there remain considerable unmet needs for NMS management. Three monoamine oxidase B inhibitors (MAO-BIs), selegiline, rasagiline, and safinamide, have become commercially available in many countries. Although an increasing number of studies have reported potential beneficial effects of MAO-BIs on QOL and NMS, there has been no consensus. Thus, the primary objective of this study was to provide an up-to-date systematic review of the QOL and NMS outcomes from the available clinical studies of MAO-BIs. We conducted a literature search using the PubMed, Scopus, and Cochrane Library databases in November 2021. We identified 60 publications relevant to this topic. Overall, rasagiline and safinamide had more published evidence on QOL and NMS changes compared with selegiline. This was likely impacted by selegiline being introduced many years prior to the field embarking on the study of NMS. The impact of MAO-BIs on QOL was inconsistent across studies, and this was unlikely to be clinically meaningful. MAO-BIs may potentially improve depression, sleep disturbances, and pain. In contrast, cognitive and olfactory dysfunctions are likely unresponsive to MAO-BIs. Given the paucity of evidence and controlled, long-term studies, the effects of MAO-BIs on fatigue, autonomic dysfunctions, apathy, and ICD remain unclear. The effects of MAO-BIs on static and fluctuating NMS have never been investigated systematically. More high-quality studies will be needed and should enable clinicians to provide personalized medicine based on a non-motor symptom profile.