bioRxiv Science⌕ Search

Biology subjects

Moreira, P.

Publications and source records attributed to Moreira, P..

3 recordsLinked to original sources

Impact of prenatal synthetic glucocorticoid exposure on the adolescent brain

Synthetic Glucocorticoids (sGC) are commonly prescribed in preterm risk pregnancies in order to improve fetal organ maturation. This administration greatly reduces perinatal and neonatal mortality and respiratory distress syndrome associated with prematurity, but preclinical evidence warns for an adverse effect of sGC in the developing brain. In this work we evaluated the long-term effects of prenatal exposure to sGC in the brain of 17 years-old adolescents using multimodal MRI. From 4607 birth registrations from Hospital de Braga - Portugal, we selected participants that were born with similar gestational age, but that were either exposed during pregnancy to sGC (n=21) or non-exposed (n=24). After obtaining a detailed clinical history, participants were subjected to an extensive neuropsychological evaluation, followed by structural and functional MRI. No differences were found in the performance on neuropsychological tests between sGC-exposed and non-exposed participants. Moreover, no differences were found in regional brain volumes. However, the sGC-exposed group presented reduced functional connectivity at rest in a network involving primarily sub-cortical, cerebellar and frontal nodes in comparison to the non-exposed group, even after controlling for confounding factors such as gestational age at birth, birth weight, and sex. Our results suggest that prenatal sGC-exposed adolescents present no significant deviations in neuropsychological performance in the dimensions that we evaluated, although they presented altered functional connectivity, highlighting the need for additional studies to understand the impact of these changes in brain functioning and in behavior. HighlightsPrenatal synthetic glucocorticoid exposure does not lead to structural changes in the adolescent brain. Adolescents prenatally exposed to synthetic glucocorticoids present altered resting state network.

neuroscience↗

Nuclear Factor-Y is a Pervasive Regulator of Neuronal Gene Expression

Nervous system function relies on the establishment of complex gene expression programs that provide neuron-type-specific and core pan-neuronal features. These complementary regulatory paradigms are controlled by terminal selector and parallel-acting transcription factors (TFs), respectively. Here, we identify the Nuclear Factor Y (NF-Y) TF as a pervasive regulator of both neuron-type-specific and pan-neuronal gene expression. Mapping global NF-Y targets reveals direct binding to the cis-regulatory regions of pan-neuronal genes and terminal selector TFs. We show that NFYA-1 controls pan-neuronal gene expression directly through binding to CCAAT boxes in target gene promoters and indirectly by regulating the expression of terminal selector TFs. Further, we find that NFYA-1 regulation of neuronal gene expression is important for neuronal activity and motor function. Thus, our research sheds light on how global neuronal gene expression programs are buffered through direct and indirect regulatory mechanisms.

neuroscience↗

The association between 25(OH)D levels, frailty status and adiposity indices in older adults

BackgroundVitamin D deficiency is common in older adults and has been linked with frailty and obesity, but it remains to be studied whether frail obese older adults are at higher risk of vitamin D deficiency. Therefore, the aim of this study is to explore the association between frailty, adiposity indices and serum 25(OH)D concentrations.\n\nMethods1447 individuals with 65 years or older, participating in a cross-sectional study (Nutrition UP 65). Frailty, according to Fried et al., body mass index (BMI), waist circumference (WC), body roundness index (BRI) and body shape index (ABSI) were evaluated. A stepwise multinomial logistic regression was carried out to quantify the association between 25(OH)D quartiles and independent variables.\n\nResultsMedian 25(OH)D levels were lower in individuals presenting both frailty and obesity (p<0.001). In the multivariate analysis, pre-frailty (OR 2.65; 95% CI 1.63-4.32) and frailty (OR 3.76; 95% CI 2.08-6.81) were associated with increased odds of lower 25(OH)D serum levels (first quartile). Regarding adiposity indices, obesity (OR 1.75; 95% CI 1.07-2.87) and the highest categories of WC (OR 3.46; 95% CI 1.95-6.15), BRI (OR 4.35; 95% CI 2.60-7.29) and ABSI (OR 3.17 95% CI 1.86-5.38) were directly associated with lower 25(OH)D serum levels (first quartile).\n\nConclusionsA positive association between frailty or obesity and lower levels of vitamin D was found. Moreover, besides BMI and WC, other indicators of body adiposity, such as BRI and ABSI, were associated with lower 25(OH)D serum concentrations.

epidemiology↗