Metabolism and nutrition have a significant role in epigenetic modifications such as DNA methylation, which can influence gene expression. Recently, it has been suggested that bioactive nutrients and gut microbiota can alter DNA methylation in the central nervous system (CNS) through the gut–brain axis, playing a crucial role in modulating CNS functions and, finally, behavior. Here, we will focus on the effect of metabolic signals in shaping brain DNA methylation during adulthood. We will provide an overview of potential interactions among diet, gastrointestinal microbiome and epigenetic alterations on brain methylation and behavior. In addition, the impact of different diet challenges on cytosine methylation dynamics in the adult brain will be discussed. Finally, we will explore new ways to modulate DNA hydroxymethylation, which is particularly abundant in neural tissue, through diet.

This systematic review addresses the use of Lactiplantibacillus (Lactobacillus) plantarum in the symptomatological intervention of neurodegenerative disease. The existence of gut microbiota dysbiosis has been associated with systemic inflammatory processes present in neurodegenerative disease, creating the opportunity for new treatment strategies. This involves modifying the strains that constitute the gut microbiota to enhance synaptic function through the gut–brain axis. Recent studies have evaluated the beneficial effects of the use of Lactiplantibacillus plantarum on motor and cognitive symptomatology, alone or in combination. This systematic review includes 20 research articles (n = 3 in human and n = 17 in animal models). The main result of this research was that the use of Lactiplantibacillus plantarum alone or in combination produced improvements in symptomatology related to neurodegenerative disease. However, one of the studies included reported negative effects after the administration of Lactiplantibacillus plantarum. This systematic review provides current and relevant information about the use of this probiotic in pathologies that present neurodegenerative processes such as Alzheimer’s disease, Parkinson’s disease and Multiple Sclerosis.

The comprehensive narrative review conducted in this study delves into the mechanisms of communication and action at the molecular level in the human organism. The review addresses the complex mechanism involved in the microbiota–gut–brain axis as well as the implications of alterations in the microbial composition of patients with neurodegenerative diseases. The pathophysiology of neurodegenerative diseases with neuronal loss or death is analyzed, as well as the mechanisms of action of the main metabolites involved in the bidirectional communication through the microbiota–gut–brain axis. In addition, interventions targeting gut microbiota restructuring through fecal microbiota transplantation and the use of psychobiotics—pre- and pro-biotics—are evaluated as an opportunity to reduce the symptomatology associated with neurodegeneration in these pathologies. This review provides valuable information and facilitates a better understanding of the neurobiological mechanisms to be addressed in the treatment of neurodegenerative diseases.

Although significant progress has been made in the rights of the LGBTQ+ community, even today this population still faces stigma and discrimination that impacts their mental health. In the case of men who have sex with men, it has been demonstrated that the use of drugs in a sexual context (chemsex) is one of the coping mechanisms and means of escape to deal with these situations. We assessed 284 native Spanish speakers’ participants, 45,4 % were not engaged in sexualised drug use (n = 129) while 54,6 % were chemsex users (n = 155) using 18,7 % of them the injected via. The participants completed six questionnaires about life and sexual satisfaction, depression, anxiety, internalised homophobia and personality. Bivariate and multivariable logistic regression were performed to assess the associations between sexual behaviour-related and psychological variables. Kruskal-Wallis H test was used to analysed the impact on mental health of the administration via. Aged, unprotected sexual relationships, positive serostatus, homonegativity and conscientiousness predicted the chemsex engagement. Furthermore, we found differences regarding the administration via. We conclude that mental health significantly correlates with the practice of chemsex, highlighting the importance of integrating mental health considerations into the prevention of risky sexual behaviors.

The objective of this narrative review is to analyze the impact of COVID-19 on the mental health of particularly vulnerable groups. This information will allow a better understanding of the determining factors that influence the appearance and/or maintenance of mood disorders. To achieve the main objective of this study, a critical review was carried out in which primary sources such as scientific articles, secondary sources such as databases, and other appropriate reference indexes were considered. The results indicated that there was an increase in the diagnosis of mood disorders and the use of medication associated with these disorders, mainly during the period of reclusion that was declared worldwide in March 2020. In addition, risk factors such as loneliness, a lack of resilience, and a lack of adequate coping strategies negatively impacted these groups. The future consequences of this may be reflected over many years thereafter, and it is important that all data obtained from this point forward be considered by mental health professionals and the general population. This review can be a starting point for looking directly at the most vulnerable populations and considering both the resources available to them and the possible aftermath of a traumatic period in everyone’s lives.

Background/Objectives: This systematic review focused on collecting the most significant findings on the impact of the administration of Bifidobacterium infantis (or Bifidobacterium longum subps. infantis) and Bifidobacterium breve, alone, in conjunction, or in combination with other strains, in the treatment of neurodegenerative diseases including Alzheimer’s disease (AD) and Parkinson’s disease (PD). These diseases are characterized by the progressive degeneration of neurons, resulting in a broad spectrum of clinical manifestations. AD is typified by a progressive decline in cognitive abilities, while PD is marked by motor symptoms associated with the loss of dopamine (DA). Methods: Five different databases, ScienceDirect, Scopus, Wiley, PubMed, and Web of Science (WoS), were reviewed and the studies were screened for inclusion by the following criteria: (i) studies that specifically evaluated the use of Bifidobacterium infantis, Bifidobacterium longum subsp. infantis, or Bifidobacterium breve as a therapeutic intervention, either in human or animal models, in the context of neurodegenerative diseases; (ii) the studies were required to address one or more of the pathologies examined in this article, and the pathologies included, but were not limited to, neurodegeneration, Alzheimer’s disease, Parkinson’s disease, and oxidative stress; (iii) the full text was accessible online; and (iv) the article was written in English. Results: The data suggest that these probiotics have neuroprotective effects that may delay disease progression. Conclusions: This study provides updated insights into the use of these Bifidobacterium strains in neurodegenerative diseases like AD and PD, with the main limitation being the limited number of clinical trials available.