Dysregulated Translation in Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder with complex genetic architecture and heterogeneous symptomatology. Increasing evidence indicates that dysregulated brain protein synthesis is a common pathogenic pathway involved in ASD. Understanding how genetic variants converge on a common molecular signaling pathway in neurons and brain circuits, resulting in ASD-relevant synaptic and behavioral phenotypes, is of great interest in the autism research community. This article focuses on ASD-risk genes and the molecular aspects leading to dysregulated protein synthesis.

CHARACTERIZATION OF PATIENTS DIAGNOSED WITH PHENYLKETONURIA IN THE NEONATAL TREATMENT REFERENCE SERVICE

Phenylketonuria is an inborn error of autosomal recessive genetic metabolism, with partial or total deficiency of the hepatic enzyme phenylalanine hydroxylase, which converts L-phenylalanine into tyrosine, causing accumulation of phenylalanine at brain and serum levels, interfering with brain protein synthesis causing several damages. This study aimed to characterize patients diagnosed with phenylketonuria at the Neonatal Screening Reference Service from 2008 to 2017. Cross-sectional analytical study with a quantitative approach with retrospective data collection from medical records and databases. Data were grouped as baby gender, date of birth, time of birth and neonatal screening examination collection, type of delivery, gestational age and prenatal status, place of origin, phenylketonuria classification and coverage rate of neonatal screening. The sample consisted of 14 patients, where 64% were male, all mothers had prenatal care and the percentage of cesarean delivery prevailed with 57.2%. Of these 85.7% reside in other states of the country and on the classification of the type of phenylketonuria 64.3% have mild phenylketonuria, as for the coverage rate there was a drop in the number of collections in the reference service. This research contributed to characterize the patient diagnosed with phenylketonuria, which allows greater knowledge about the disease carriers, as well as favoring the reduction of irreversible sequels, expenses and morbidity.

EFFECTIVENESS OF PHENYLKETONURIA DIAGNOSIS IN THE NEONATAL TREATMENT REFERENCE SERVICE

Phenylketonuria is an inborn error of metabolism of autosomal recessive inheritance, with partial or total deficiency of the phenylalanine hydroxylase hepatic enzyme, which converts L-phenylalanine into tyrosine, thus causing accumulation of phenylalanine at the brain and serum level, interfering in the brain protein synthesis and entailing serious deficits. The objective of this study was to analyze the effectiveness of Phenylketonuria Diagnosis in the neonatal treatment reference service. This is a cross-sectional, analytical study with a quantitative approach, documented with retrospective data collection. Sociodemographic data, diagnosis, onset of treatment and the coverage rate analysis were grouped on a quadrennial basis. The sample consisted of 14 patients, from whom 57.1% had records of birth and collection time. In variable days of life, 28.6% were screened within the recommended period, 71.4% were diagnosed up to one month of life and 1 case at 3 years of age, for the onset of treatment (14.3%). The ideal collection would be performed up to 30 days of life. The lowest coverage rate for quadrennial was between 2014-2017 with 84.3%, with an incidence of 1:21,933. In conclusion, we highlight the need to optimize the neonatal screening service in order to make early diagnosis, begin specific treatment and minimize or eradicate irreversible sequelae.

Brain Protein Synthesis Rates in the UM-HET3 Mouse Following Treatment With Rapamycin or Rapamycin With Metformin

Treatment with the mechanistic target of rapamycin (mTOR) inhibitor, rapamycin (RAP), alone and in combination with the antidiabetic drug, metformin (RAP+MET), extends lifespan in mice. The mechanisms underlying lifespan extension are unclear. One possibility is improved capacity for proteostatic maintenance. We have previously characterized peripheral protein synthesis rates following treatment with RAP. However, it is unknown if RAP+MET elicits similar changes, or if either treatment affects protein synthesis in the brain. We hypothesized that 8 weeks of treatment with RAP and RAP+MET would alter brain protein synthesis rates to reflect proteostatic processes. Using the stable isotopic tracer, deuterium oxide (D2O), we demonstrate in UM-HET3 mice that protein synthesis rates measured in whole brain were unaffected by treatment in young male mice, whereas RAP+MET decreased mitochondrial protein synthesis in young females. Conversely, RAP increased mitochondrial protein synthesis rates in older females. Activity through the AMPK/mTOR pathway was affected in a sex-specific manner in young mice, and minimal changes were observed in the older cohort. Thus, we establish D2O for measurements of biogenesis in the brain. These results provide initial insights into the effects of RAP and RAP+MET on brain protein synthesis. Additionally, these data emphasize that responses to slowed aging treatments vary with sex and age.

Effects of nutritional state, aging and high chronic intake of sucrose on brain protein synthesis in rats: modulation of it by rutin and other micronutrients

Brain protein synthesis was decreased during aging, restored by micronutrients, and unchanged by sucrose, in correlation with variations in TNF-α gene expression.