Brief Report: Low Rates of Herpesvirus Detection in Blood of Individuals with Autism Spectrum Disorder and Controls

Association between human herpesviruses infections and childhood neurodevelopmental disorders: insights from two-sample mendelian randomization analyses and systematic review with meta-analysis

BACKGROUND

The potential roles of viral infections in neurodevelopmental disorders (NDDs) have been suggested based on previous studies. Given the high prevalence of human herpesviruses (HHVs), the associations between HHVs infection and the risk of NDDs warrant explored.

METHODS

Our study employs a two-sample Mendelian randomization (MR) analysis and systematic review with meta-analysis to investigate whether genetically predicted HHVs infection are linked to three main childhood NDDs-autism spectrum disorder (ASD), attention deficit hyperactivity disorder (ADHD), and Tourette syndrome (TS). We utilized genetic variants associated with HHV infections in genome-wide association study (GWAS) summary datasets of European populations to establish instrumental variables and statistics for three NDDs obtained from Psychiatric Genomics Consortium. MR analysis was performed using inverse-variance weighted, MR Egger, weighted median, simple median, weighted mode, and MR-PRESSO. In addition, publications associating HHVs infection with three NDDs were systematically searched using PubMed, Web of Science, and three Chinese databases for meta-analyses.

RESULTS

The MR results found no evidence to support a link between genetically predicted HHVs infection and the risk of NDDs based on existing datasets. Twenty-seven observational studies on children with HHVs infection and NDDs were considered eligible. Meta-analysis showed that cytomegalovirus and HHV-6 infection were related with ASD, while Epstein-Barr virus and cytomegalovirus infection were associated with TD in Chinese population.

CONCLUSIONS

These results contribute to a comprehensive understanding of the possibilities underlying HHV infections in affecting childhood NDDs. Further research is necessary to include larger and more robust statistics of HHV infections and NDDs.

TRIAL REGISTRATION

This systematic review was registered at PROSPERO as CRD42024554169. Retrospectively registered 26 July 2024.

Treating reactivated EBV, HHV-6, HHV-7 infections in children with Autism Spectrum disorder associated with genetic folate cycle disruptions: Outcomes after Valacyclovir, Valganciclovir and Artesunate

Immune dysfunction causes the reactivation of herpesviruses in children with autism spectrum disorder (ASD) associated with the genetic folate cycle deficiency (GFCDs). The aim – to investigate the efficacy of valaciclovir, valganciclovir, and artesunate in reactivated Epstein-Barr virus (EBV), herpes virus type 6 (HHV-6) and herpes virus type 7 (HHV-7) infections in children with ASD. The treatment group consisted of 225 children aged 2 to 9 years who had GFCDs and ASD. The diagnosis of EBV, HHV-6, and HHV-7 reactivations was made by blood leukocyte PCR. Valacyclovir (500-1000 mg twice per day), valganciclovir (225-450mg twice per day), and artesunate (25-50mg twice a day) were prescribed for 3 months. The control group (no antiviral treatment) included 52 children who were comparable in age and diagnosis. Valacyclovir treatment achieved undetectable EBV DNA in 39% of cases. Valganciclovir and artesunate performed complete response rates of 47 and 62%, respectively (р<0.05; Z<Z0.05). HHV-6 DNA was undetectable in 29% of valacyclovir-treated patients. Valganciclovir and artesunate achieved complete response rates of 32 and 57%, respectively (p <0.05; Z<Z0.05). HHV-7 DNA was not detected in 24% of valacyclovir-treated patients, but in 35 and 44%, respectively (p <0.05, Z<Z0.05) in valganciclovir and artesunate groups. There was an association found between negative PCR results and normalized S-100 protein and neuron-specific enolase serum concentrations. Antiviral treatments disrupted the natural course of reactivated EBV, HHV-6, and HHV-7 infections in ASD children, exerting a neuroprotective effect, with artesunate being the most effective option and EBV - the most sensitive to antiviral drugs.

Transcriptomic Analysis Reveals Abnormal Expression of Prion Disease Gene Pathway in Brains from Patients with Autism Spectrum Disorders

The role of infections in the pathogenesis of autism spectrum disorder (ASD) is still controversial. In this study, we aimed to evaluate markers of infections and immune activation in ASD by performing a meta-analysis of publicly available whole-genome transcriptomic datasets of brain samples from autistic patients and otherwise normal people. Among the differentially expressed genes, no significant enrichment was observed for infectious diseases previously associated with ASD, including herpes simplex virus-1 (HSV-1), cytomegalovirus and Epstein–Barr virus in brain samples, nor was it found in peripheral blood from ASD patients. Interestingly, a significant number of genes belonging to the “prion diseases” pathway were found to be modulated in our ASD brain meta-analysis. Overall, our data do not support an association between infection and ASD. However, the data do provide support for the involvement of pathways related to other neurodegenerative diseases and give input to uncover novel pathogenetic mechanisms underlying ASD.

Neuroprotective potential of solanesol in intracerebroventricular propionic acid induced experimental model of autism: Insights from behavioral and biochemical evidence

Autism is the category used within the newest edition of the diagnostic and statistical manual of neurodevelopmental disorders. Autism is a spectrum of disorder where a variety of behavioural patterns observed in autistic patients, such as stereotypes and repetitive behavior, hyperexcitability, depression-like symptoms, and memory and cognitive dysfunctions. Neuropathological hallmarks that associated with autism are mitochondrial dysfunction, oxidative stress, neuroinflammation, Neuro-excitation, abnormal synapse formation, overexpression of glial cells in specific brain regions like cerebellum, cerebral cortex, amygdala, and hippocampus. ICV injection of propionic acid (PPA) (4 μl/0.26 M) mimics autistic-like behavioral and biochemical alterations in rats. Literature findings reveal that there is a link between autism neuronal mitochondrial coenzyme-Q10 (CoQ10) and ETC-complexes dysfunctions are the keys pathogenic events for autism. Therefore, in the current study, we explore the neuroprotective interventions of Solanesol (SNL) 40 and 60 mg/kg alone and in combination with standard drugs Aripiprazole (ARP) 5 mg/kg, Citalopram (CTP) 10 mg/kg, Memantine (MEM) 5 mg/kg and Donepezil (DNP) 3 mg/kg to overcome behavioral and biochemical alterations in PPA induced experimental model of Autism. Chronic treatment with SNL 60 mg/kg in combination with standard drug shows a marked improvement in locomotion, muscle coordination, long-term memory and the decrease in depressive behavior. While, chronic treatment of SNL alone and in combination with standard drug aripiprazole, citalopram, donepezil, and memantine shows the Neuroprotective potential by enhancing the cognitive deficits, biochemical alterations along with reducing the level of inflammatory mediators and oxidative stress.