Targeting Gut Dysbiosis and Microbiome Metabolites for the Development of Therapeutic Modalities for Neurological Disorders.

The gut microbiota, composed of numerous species of microbes, works in synergy with the various organ systems in the body to bolster our overall health and well-being. The most well-known function of the gut microbiome is to facilitate the metabolism and absorption of crucial nutrients, such as complex carbohydrates, while also generating vitamins. In addition, the gut microbiome plays a crucial role in regulating the functioning of the central nervous system (CNS). Host genetics, including specific genes and single nucleotide polymorphisms (SNPs), have been implicated in the pathophysiology of neurological disorders, including Parkinson's disease (PD), Alzheimer's disease (AD), and autism spectrum disorder (ASD). The gut microbiome dysbiosis also plays a role in the pathogenesis of these neurodegenerative disorders, thus perturbing the gut-brain axis. Overproduction of certain metabolites synthesized by the gut microbiome, such as short-chain fatty acids (SCFAs) and p-cresyl sulfate, are known to interfere with microglial function and trigger misfolding of alpha-synuclein protein, which can build up inside neurons and cause damage. By determining the association of the gut microbiome and its metabolites with various diseases, such as neurological disorders, future research will pave the way for the development of effective preventive and treatment modalities.

Efficacy of coping mechanisms used during COVID-19 as reported by parents of children with autism.

The COVID-19 pandemic's alterations to daily life have been especially challenging for families with Autism Spectrum Disorder (ASD), worsening the core features of ASD and overall mental health. With the increased need for effective coping, the current retrospective study used data from a survey regarding parent reports of how often their child with ASD used certain coping strategies (frequency), as well as the extent to which they felt their child benefitted from their use (efficacy) in mitigating stress during the pandemic. This retrospective study Repeated measures ANOVAs were conducted to evaluate whether there were significant differences in both frequency and efficacy ratings for each coping strategy, for the entire sample as well as for three children's age groups. Using Spearman's rank-order correlations, correlation coefficients between the frequency and efficacy of each coping strategy were explored. Results revealed that maladaptive strategies were used more frequently than adaptive strategies, while parent routine as the most frequently used and efficacious for all age groups. Additionally, for adaptive strategies, humor and focusing on the positive had the strongest correlations between frequency and efficacy ratings amongst all age groups. Of the maladaptive strategies, repetitive behaviors, rumination, and isolation had the strongest correlations for the youngest, middle, and oldest age groups, respectively. Further, for each age group, the adaptive coping strategies had stronger correlations between frequency and efficacy than the maladaptive ones. It is our hope that the results of this study will lay the foundation for developing adaptive coping strategies to alleviate stress in children with ASD. Further investigations using a larger cohort are warranted to determine effective coping strategies for individuals with ASD across a range of situations, including acute stressors (such as future public health emergencies and natural disasters), as well as common daily stressors.

Genetic ablation of metabotropic glutamate receptor 5 in rats results in an autism-like behavioral phenotype.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by deficits in communication, and social skills, as well as repetitive and/or restrictive interests and behaviors. The severity of ASD varies from mild to severe, drastically interfering with the quality of life of affected individuals. The current occurrence of ASD in the United States is about 1 in 44 children. The precise pathophysiology of ASD is still unknown, but it is believed that ASD is heterogeneous and can arise due to genetic etiology. Although various genes have been implicated in predisposition to ASD, metabotropic glutamate receptor 5 (mGluR5) is one of the most common downstream targets, which may be involved in autism. mGluR5 signaling has been shown to play a crucial role in neurodevelopment and neural transmission making it a very attractive target for understanding the pathogenesis of ASD. In the present study, we determined the effect of genetic ablation of mGluR5 (Grm5) on an ASD-like phenotype using a rat model to better understand the role of mGluR5 signaling in behavior patterns and clinical manifestations of ASD. We observed that mGluR5 Ko rats exhibited exaggerated self-grooming and increased marble burying, as well as deficits in social novelty. Our results suggest that mGluR5 Ko rats demonstrate an ASD-like phenotype, specifically impaired social interaction as well as repetitive and anxiety-like behavior, which are correlates of behavior symptoms observed in individuals with ASD. The mGluR5 Ko rat model characterized in this study may be explored to understand the molecular mechanisms underlying ASD and for developing effective therapeutic modalities.

The impact of COVID-19 on individuals with ASD in the US: Parent perspectives on social and support concerns.

The COVID-19 pandemic's disruptions to daily routines and services have proven especially challenging for children with autism spectrum disorder (ASD) and their families. The current retrospective study aimed to determine the impact of the COVID-19 pandemic's social environmental changes on parental ratings of personal and child concerns about family conflict, opportunities for social interaction, and loss of institutional support (school and therapy services). Analyses of responses from families with ASD in the US determined differences in concerns across three time points which were measured simultaneously: prior to COVID-19, at the start of COVID-19, and at the time of survey completion. From our sample of 246 school-aged children, parents retrospectively reported significantly increasing levels of concern for both themselves and their children over time, with parents' personal concern levels rated consistently higher than their ratings of their child's level of concern. Concerns about loss of institutional support were higher for parents of children reported as having co-occurring intellectual disability. Further, parents of younger children also reported more concerns about loss of services, as well as more social concerns. For parent ratings of child concerns, children who were reportedly aware of COVID-19 were determined to have higher levels of social concerns and concerns about loss of institutional support. Meanwhile, the child's age and gender did not impact their parent ratings of child concerns. The increased level of parental and child-perceived concerns over the course of the pandemic suggests a need for improved service delivery and support for these families. The high levels of concerns observed in the current study provide support for the need to assess families' priorities and tailor services to best meet families' needs. This will potentially increase the quality of life of family members, and improve ASD services across the lifespan, and improve outcomes.

Altered Blood Brain Barrier Permeability and Oxidative Stress in Cntnap2 Knockout Rat Model.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by three core symptoms, specifically impaired social behavior, stereotypic/repetitive behaviors, and sensory/communication deficits. Although the exact pathophysiology of ASD is still unknown, host genetics, oxidative stress, and compromised blood brain barrier (BBB) have been implicated in predisposition to ASD. With regards to genetics, mutations in the genes such as CNTNAP2 have been associated with increased susceptibility of developing ASD. Although some studies observed conflicting results suggesting no association of CNTNAP2 with ASD, other investigations correlated this gene with autism. In addition, CNTNAP2 mediated signaling is generally considered to play a role in neurological disorders due to its critical role in neurodevelopment, neurotransmission, and synaptic plasticity. In this investigation, we studied BBB integrity and oxidative stress in Cntnap2-/- rats. We observed that the BBB permeability was significantly increased in Cntnap2-/- rats compared to littermate wild-type (WT) animals as determined by FITC-dextran and Evans blue assay. High levels of thiobarbituric acid reactive substances and lower amounts of reduced glutathione were observed in brain homogenates of Cntnap2-/- rats, suggesting oxidative stress. Brain sections from Cntnap2-/- rats showed intense inducible nitric oxide synthase immunostaining, which was undetectable in WT animals. Quantification of nitric oxide in brain homogenates revealed significantly high levels in Cntnap2-/- rats compared to the control group. As increased permeability of the BBB and oxidative stress have been observed in ASD individuals, our results suggest that Cntnap2-/- rats have a high construct and face validity and can be explored to develop effective therapeutic modalities.