0000000000208761
AUTHOR
Malena Dos Santos Guilherme
showing 7 related works from this author
Alzheimer's disease in the gut : major changes in the gut of 5xFAD model mice with ApoA1 as potential key player
2019
Alzheimer's disease (AD) affects around 33 million people worldwide, which makes it the most prominent form of dementia. The main focus of AD research has been on the central nervous system (CNS) for long, but in recent years, the gut gained more attention. The intestinal tract is innervated by the enteric nervous system (ENS), built of numerous different types of neurons showing great similarity to neurons of the CNS. It already has been demonstrated that the amyloid precursor protein, which plays a major role in AD pathology, is also expressed in these cells. We analyzed gut tissue of AD model mice (5xFAD) and the respective wild-type littermates at different pathological stages: pre-path…
Elevated Testosterone Level and Urine Scent Marking in Male 5xFAD Alzheimer Model Mice
2019
Background:Function of the Amyloid Precursor Protein (AβPP) and its various cleavage products still is not unraveled down to the last detail. While its role as a source of the neurotoxic Amyloid beta (Aβ) peptides in Alzheimer’s Disease (AD) is undisputed and its property as a cell attachment protein is intriguing, while functions outside the neuronal context are scarcely investigated. This is particularly noteworthy because AβPP has a ubiquitous expression profile and its longer isoforms, AβPP750 and 770, are found in various tissues outside the brain and in non-neuronal cells.Objective:Here, we aimed at analyzing the 5xFAD Alzheimer’s disease mouse model in regard to male sexual function.…
Identification of Patulin from Penicillium coprobium as a Toxin for Enteric Neurons
2019
The identification and characterization of fungal commensals of the human gut (the mycobiota) is ongoing, and the effects of their various secondary metabolites on the health and disease of the host is a matter of current research. While the neurons of the central nervous system might be affected indirectly by compounds from gut microorganisms, the largest peripheral neuronal network (the enteric nervous system) is located within the gut and is exposed directly to such metabolites. We analyzed 320 fungal extracts and their effect on the viability of a human neuronal cell line (SH-SY5Y), as well as their effects on the viability and functionality of the most effective compound on primary ent…
N6 -Methyladenosine Modification in Chronic Stress Response Due to Social Hierarchy Positioning of Mice
2021
Appropriately responding to stressful events is essential for maintaining health and well-being of any organism. Concerning social stress, the response is not always as straightforward as reacting to physical stressors, e.g., extreme heat, and thus has to be balanced subtly. Particularly, regulatory mechanisms contributing to gaining resilience in the face of mild social stress are not fully deciphered yet. We employed an intrinsic social hierarchy stress paradigm in mice of both sexes to identify critical factors for potential coping strategies. While global transcriptomic changes could not be observed in male mice, several genes previously reported to be involved in synaptic plasticity, l…
Apolipoprotein A1 in Cerebrospinal Fluid Is Insufficient to Distinguish Alzheimer's Disease from Other Dementias in a Naturalistic, Clinical Setting.
2020
Apolipoprotein A1 (ApoA1) is the major protein component of the high-density lipoprotein and involved in cholesterol transport. Disruption of cholesterol homeostasis has been identified as a contributing factor for Alzheimer's disease (AD). Moreover, polymorphisms of ApoA1 have been associated with higher risk of disease onset and cognitive decline. Therefore, ApoA1 has been suggested as a biomarker in AD. Here, we tested a small cohort of AD and non-AD dementia patients and measured levels of ApoA1 in cerebrospinal fluid. Our results indicate that ApoA1 might not be applicable to distinguish AD from other forms of dementia.
The impact of the gut microbiome in Alzheimer's disease
2020
Abstract Alzheimer's disease is a devastating neurodegenerative disease clearly characterized by loss of synapses, changes in metabolism, and neuronal death in brain tissue. The impact of nutrition and other lifestyle factors on pathomechanisms has been extensively investigated in recent decades. However, one main issue has been out of focus during these research efforts—the human body is not a single entity but provides an ecological niche for a huge number of other organisms, its microbial flora. These microorganisms outnumber the host's genetic pool indisputably. While the human encodes for 30,000 genes, the microbiome of the gastrointestinal tract inherits a multitude of commensal micro…
Impact of Acute and Chronic Amyloid-β Peptide Exposure on Gut Microbial Commensals in the Mouse
2020
Alzheimer’s disease (AD) is the most common form of dementia. Besides its cognitive phenotype, AD leads to crucial changes in gut microbiome composition in model mice and in patients, but the reported data are still highly inconsistent. Therefore, we investigated chronic effects of AD-characteristic neurotoxic amyloid-β (Aβ) peptides as provided by transgenic overexpression (5xFAD mouse model) and acute effects due to oral application of Aβ on gut microbes. Astonishingly, one-time feeding of wild type mice with Aβ42 provoked immediate changes in gut microbiome composition (β diversity) as compared to controls. Such obvious changes were not observed when comparing 5xFAD mice with wild type l…