Biology subjects

Tonon, C.

Publications and source records attributed to Tonon, C..

2 recordsLinked to original sources

bioRxiv2026

Alterations of gut microbiota in Down syndrome and their association with Alzheimer's disease

Structured AbstractO_ST_ABSINTRODUCTIONC_ST_ABSAdults with Down syndrome (DS) have a higher risk of developing Alzheimers disease (AD). As gut microbiota (GM) alterations have been reported in AD, we investigated their association with cognitive decline and plasma AD biomarkers in DS. METHODSFecal and plasma samples were collected from 58 adults with DS (21-75 years) and 30 euploid controls (CTRL; 25-83 years). GM was profiled using 16S rRNA sequencing. Major Neurocognitive Disorder (NcD) was diagnosed according to DSM-5 criteria. Plasma levels of p-Tau181, NfL, and GFAP were measured using the Simoa platform. RESULTSCompared with CTRL, DS showed significant changes in UBA1819 and Intestinibacter genera, previously reported to be associated with mild cognitive impairment. Furthermore, DS with NcD were characterized by a reduced abundance of Roseburia genus, which was also negatively associated with plasma levels of AD biomarkers. CONCLUSIONAdults with DS display AD-associated changes in GM partially resembling those previously reported in euploid AD patients

microbiology↗

bioRxiv2020

Melanopsin retinal ganglion cell-driven contribution to visual and cognitive brain responses in LHON

Melanopsin retinal ganglion cells (mRGCs) are intrinsically photosensitive photoreceptors contributing to visual and non-image-forming functions of the eye. Isolating mRGC roles in humans is challenging, therefore mRGCs functions remains to be fully characterized. We explored mRGCs contribution to light-driven visual and cognitive brain responses in Lebers Hereditary Optic Neuropathy (LHON), given mRGC relative sparing in LHON. Twelve patients and twelve matched healthy controls (HC) participated in an fMRI protocol including visual and visual-cognitive paradigms under blue (480nm) and red light (620nm). Higher occipital activation was found in response to sustained blue vs. red stimulation in LHON vs. HC. Similarly, brain responses to the executive task were larger under blue vs. red light in LHON over lateral prefrontal cortex. These findings are in line with LHON mRGCs relative sparing and support mRGCs contribution to non-visual and visual functions in humans, with potential implication for visual rehabilitation in optic neuropathy patients.

neuroscience↗