👤 Miguel E Renteria

Exposure to a Western diet during gestation and lactation adversely impacts offspring mood, learning, and memory. We determined if high dose maternal methyl donor nutrient (MDN) supplementation ameliorated the effects of a high fat/high sucrose (HFS) diet during gestation and lactation on the behavior of young, adult offspring. Rat dams consumed the following diets through gestation and lactation: [1] AIN93G control (CON) diet, [2] 45% fat diet with sucrose (HFS), [3] CON diet supplemented with folic acid, B MDN supplementation increased depression-related behavior regardless of maternal base diet (P = 0.003). Learning under stress was reduced in offspring of MDN supplemented dams evidenced by fewer SBET escapes (P = 0.042) and increased escape latency in FR1 trials (P = 0.037). MDNs did not alter novelty reactivity, anxiety-related behavior, or working memory but improved reference memory (P = 0.023). MDNs did not affect corticosterone, reduced BDNF when dams consumed the HFS diet (P = 0.025), and tended to increase DNA methylation (P = 0.065). Maternal MDN supplementation increased depression-related behavior and decreased learning under stress, indicating high dose MDN supplementation may not be warranted. Show less

Optical coherence tomography (OCT) is a non-invasive technique to measure retinal layer thickness, providing insights into retinal ganglion cell integrity. Studies have shown reduced retinal nerve fibre layer (RNFL) and ganglion cell inner plexiform layer (GCIPL) thickness in Parkinson's disease (PD) patients. However, it is unclear if there is a common genetic overlap between the macula and peripapillary estimates with PD and if the genetic risk of PD is associated with changes in ganglion cell integrity estimates in young adults. Western Australian young adults underwent OCT imaging. Their pRNFL, GCIPL, and overall retinal thicknesses were recorded, as well as their longitudinal changes between ages 20 and 28. Polygenic risk scores (PRS) were estimated for each participant based on genome-wide summary data from the largest PD genome-wide association study conducted to date. We further evaluated whether PD PRS was associated with changes in thickness at a younger age. To evaluate the overlap between retinal integrity estimates and PD, we annotated and prioritised genes using mBAT-combo and performed colocalisation through the GWAS pairwise method and HyPrColoc. We used a multi-omic approach and single-cell expression data of the retina and brain through a Mendelian randomisation framework to evaluate the most likely causal genes. Genes prioritised were analysed for missense variants that could have a pathogenic effect using AlphaMissense. We found a significant association between the Parkinson's disease polygenic risk score (PD PRS) and changes in retinal thickness in the macula of young adults assessed at 20 and 28 years of age. Gene-based analysis identified 27 genes common to PD and retinal integrity, with a notable region on chromosome 17. Expression analyses highlighted NSF, CRHR1, and KANSL1 as potential causal genes shared between PD and ganglion cell integrity measures. CRHR1 showed consistent results across multiple omics levels. Our findings suggest that retinal measurements, particularly in young adults, could be a potential marker for PD risk, indicating a genetic overlap between retinal structural integrity and PD. The study highlights specific genes and loci, mainly on chromosome 17, as potential shared etiological factors for PD and retinal changes. Our results highlight the importance of further longitudinal studies to validate retinal structural metrics as early indicators of PD predisposition. Show less