Neuroepigenetics of ageing and neurodegeneration-associated dementia: An updated review

Gene expression is tremendously altered in the brain during memory acquisition, recall, and forgetfulness. However, non-genetic factors, including environmental elements, epigenetic changes, and lifestyle, have grabbed significant attention in recent years regarding the etiology of neurodegenerative diseases (NDD) and age-associated dementia. Epigenetic modifications are essential in regulating gene expression in all living organisms in a DNA sequence-independent manner. The genes implicated in ageing and NDD-related memory disorders are epigenetically regulated by processes such as DNA methylation, histone acetylation as well as messenger RNA editing machinery. The physiological and optimal state of the epigenome, especially within the CNS of humans, plays an intricate role in helping us adjust to the changing environment, and alterations in it cause many brain disorders, but the mechanisms behind it still need to be well understood. When fully understood, these epigenetic landscapes could act as vital targets for pharmacogenetic rescue strategies for treating several diseases, including neurodegeneration- and age-induced dementia. Keeping this objective in mind, this updated review summarises the epigenetic changes associated with age and neurodegeneration-associated dementia.

Impact of insomnia on mental status among chronic disease patients during Covid-19 pandemic

Background

The Coronavirus disease (Covid-19) 2019 pandemic had a serious impact on the mental health of individuals globally. A lack of psychological well-being on the part of individuals with chronic diseases might increase the risk of developing symptoms such as insomnia, depression, and anxiety.

Objectives

The aim of this study is to evaluate the prevalence of insomnia, depression, and anxiety among patients with chronic disease during the Covid-19 pandemic in Oman.

Methods

This is a web-based cross-sectional study conducted between June 2021 and September 2021. Insomnia was assessed by using the Insomnia Severity Index (ISI), while depression and anxiety were measured using the Hospital Anxiety and Depression Scale (HADS).

Results

Of the 922 chronic disease patients who participated, 77% (n = 710) reported insomnia, while the mean score for the ISI was11.38 (SD 5.82). Depression and anxiety were prevalent among the participants with 47% and 63% respectively. The participants' mean with regard to the sleep duration items was 7.04 (SD = 1.59) hours per night, whereas the mean in terms of sleep latency was 38.18 minutes (SD = 31.81). Logistic regression analysis revealed that insomnia was positively associated with depression and anxiety.

Conclusions

This study demonstrated that chronic disease patients had a high prevalence of insomnia during the Covid-19 pandemic. Psychological support is recommended in order to help such patients reduce the level of insomnia. Furthermore, a routine assessment of levels of insomnia, depression and anxiety is essential, in order to help identify appropriate intervention and management measures.

Regulation of DNA Methylation by Cannabidiol and Its Implications for Psychiatry: New Insights from In Vivo and In Silico Models

Cannabidiol (CBD) is a non-psychotomimetic compound present in cannabis sativa. Many recent studies have indicated that CBD has a promising therapeutic profile for stress-related psychiatric disorders, such as anxiety, schizophrenia and depression. Such a diverse profile has been associated with its complex pharmacology, since CBD can target different neurotransmitter receptors, enzymes, transporters and ion channels. However, the precise contribution of each of those mechanisms for CBD effects is still not yet completely understood. Considering that epigenetic changes make the bridge between gene expression and environment interactions, we review and discuss herein how CBD affects one of the main epigenetic mechanisms associated with the development of stress-related psychiatric disorders: DNA methylation (DNAm). Evidence from in vivo and in silico studies indicate that CBD can regulate the activity of the enzymes responsible for DNAm, due to directly binding to the enzymes and/or by indirectly regulating their activities as a consequence of neurotransmitter-mediated signaling. The implications of this new potential pharmacological target for CBD are discussed in light of its therapeutic and neurodevelopmental effects.

Nutrition, Epigenetics, and Major Depressive Disorder: Understanding the Connection

Major depressive disorder (MDD) is a complex, multifactorial disorder of rising prevalence and incidence worldwide. Nearly, 280 million of people suffer from this leading cause of disability in the world. Moreover, patients with this condition are frequently co-affected by essential nutrient deficiency. The typical scene with stress and hustle in developed countries tends to be accompanied by eating disorders implying overnutrition from high-carbohydrates and high-fat diets with low micronutrients intake. In fact, currently, coronavirus disease 2019 (COVID-19) pandemic has drawn more attention to this underdiagnosed condition, besides the importance of the nutritional status in shaping immunomodulation, in which minerals, vitamins, or omega 3 polyunsaturated fatty acids (ω-3 PUFA) play an important role. The awareness of nutritional assessment is greater and greater in the patients with depression since antidepressant treatments have such a significant probability of failing. As diet is considered a crucial environmental factor, underlying epigenetic mechanisms that experience an adaptation or consequence on their signaling and expression mechanisms are reviewed. In this study, we included metabolic changes derived from an impairment in cellular processes due to lacking some essential nutrients in diet and therefore in the organism. Finally, aspects related to nutritional interventions and recommendations are also addressed.

Psychiatric genetic counseling for patients with schizophrenia and their families

Steady progress in the field of psychiatric genetics, generating new and fascinating insight into the genetic and phenotypic complexity of schizophrenia and other serious mental illnesses, have created an increased need of psychiatric genetic counseling. It is a crucial aspect of psychiatric clinical practice to ensure a balanced approach that takes into consideration genetic and environmental risk factors and ongoing education in this rapidly developing field is essential. Genetic counseling will be increasingly important to assist patients with schizophrenia and their families to make a meaningful informed decision about genetic testing. It will preempt unrealistic expectations, discrimination and stigma related to incomplete understanding of genetic test results in the psychiatric context.