Emerging Concepts in Basic Science
After great success in 2016 and 2017, this series highlighting basic dementia science will be a can't-miss aspect of AAIC 2018.
The Scientific Program Committee introduced the Emerging Concepts series, an innovative aspect of the AAIC program designed specifically for basic dementia science.
One Emerging Concepts session will be held each day from Sunday to Tuesday of the conference, concluding with a panel discussion on Wednesday that includes the three session leads.
Learn more about the 2018 sessions below.
Sunday, July 22 | 2 – 3:30 p.m.
Lead: Rashid Deane
Brain State and Clearance from the Parenchyma
Rashid Deane, University of Rochester Medical Center, United States
Bi-Directional Relationship between Circadian Rhythms and Alzheimer's Disease Pathology
Erik S. Musiek, Washington University in St. Louis, United States
Impact of General Anesthesia on Intraparenchymal CSF Circulation: Implications for Alzheimer’s Disease
Maxime Gauberti, Institut National de la Santé et de la Recherche Médicale, France
Sleep Fragmentation and Brain Structural Changes in Aging and Alzheimer’s Disease
Andrew Lim, University of Toronto, Canada
While sleep is essential for good health, the implications of its disruption in still not completely understood. The biological clock synchronizes the sleep-wake cycle to the light–dark cycle. This homeostatic mechanism is controlled by many factors, including biological, physical and emotional. Disturbances of the sleep-wake cycle have been associated with aging, and neurodegenerative diseases, such as Alzheimer’s disease (AD). Since levels of amyloid-β (Aβ) peptides in the interstitial fluid (ISF) are greater during the wake phase than that of the sleep state, disruption of sleep quality may contribute to the Aβ accumulation and AD pathogenesis. In addition, accumulated Aβ may further disrupt sleep pattern and amplify Aβ accumulation. While dysfunctional Aβ clearance is a major contributor to amyloid-β accumulation in the aging brain, it’s unclear how the sleep-wake cycle modulates these processes. Aβ peptides are cleared from brain by mainly receptor-mediated transport across the blood-brain barrier (BBB), and by ISF diffusion/bulk flow and degradation. General anesthesia (GA) has been used to study the effects of altered brain state, since it induces reversible unconsciousness, analgesia, amnesia, and akinesia. However, the role of GA on cerebrospinal fluid (CSF) distribution in brain is contradictory. This session will address the bi-directional relationship between circadian rhythm and AD, the role of brain state on ISF clearance and CSF distribution and sleep disruption in brain structural changes. This should stimulate constructive discussion leading to a better understanding of circadian rhythm and AD, and therapeutic approaches to slow the on-set of cognitive decline and AD development.
Monday, July 23 | 2 – 3:30 p.m.
Lead: Karl Herrup
Non-neuronal cells contribute heavily to normal brain function and play underappreciated roles in the etiology of neurodegenerative disease. An important example of this concept is the oligodendrocyte and the sheath of myelin that it creates around neuronal axons. The oligodendrocyte participates in a multidimensional trophic interaction with neurons and astrocytes. The integrity of the myelin sheath helps set axonal conduction velocity, thus helping 'tune' the neuronal network. Finally, white matter integrity tracks closely with cognition such that in normal human development and aging, there is a strong inverted-U-shaped correlation between cognitive capacity and myelin integrity. The importance of this relationship to Alzheimer's disease – where normal age-related myelin loss is profoundly accelerated – was first recognized by Bartzokis over 15 years ago, making this session more aptly entitled: a RE-emerging concept in AD. Speakers will describe how modern imaging methods have enhanced the precision with which we can describe myelin in the living human – arguing for its use as an important AD biomarker. The rapid progress in our understanding of the cell biology of the oligodendrocyte will also be discussed, including the unexpected importance of gray matter myelin. The contribution of the oligodendrocyte to brain aging will also be described along with how loss of genomic integrity acts as a driver of the oligodendrocyte aging process. The broad goal of the session, therefore, is to draw attention to this understudied area of brain biology and promote its incorporation into new diagnostic and therapeutic strategies to combat dementia.
Tuesday, July 24 | 2 – 3:30 p.m.
Lead: Giovanni Frisoni
Studying and Tracking the Human Microbiota: Opportunities and Challenges for the Alzheimer’s Community
Jack Gilbert, The University of Chicago, United States
Gut Microbiome Alterations in Parkinson’s Disease: Preclinical and Clinical Evidence
Kathleen M. Shannon, University of Wisconsin, United States
Gut Microbiome Alterations in Alzheimer’s Disease: Preclinical Evidence
Sangram S. Sisodia, The University of Chicago, United States
Gut Microbiome Alterations in Alzheimer’s Disease: Clinical Evidence and the Way Forward
Giovanni B. Frisoni, Lab Alzheimer’s Neuroimaging & Epidemiology, IRCCS Fatebenefratelli, Italy
A better understanding of the composition and function of the trillions of bacteria and viruses hosted in the guts of each human (a.k.a. the gut microbiota) and their cross-talk with the host’s body organs may allow figuring out the pathophysiology of diseases of yet unknown ethology. Evidence is mounting that a specific composition of the gut microbiota (GMB), i.e. one or some bacterial strains, may affect brain function and human behavior Parkinson’s and Alzheimer’s disease, depression, multiple sclerosis, and autism. The mediators of the gut-brain cross-talk are circulating mediators, either produced by microbes themselves or induced on the immune-inflammatory system, activated B- and T- cells, and the vagus nerve. The therapeutic perspectives are attractive, given the ease of access of the digestive system and modification of the composition of the gut microbiota. However, challenges are huge due to the complexity of a highly dynamic eco-system comprising up to 4x1013 microorganisms from 1,000 bacterial strains with 3x108 genes and metabolic functions relatively de-coupled from current taxonomy. This symposium will deliver an up-to-date overview of research on the role of the microbiota in human disease, and clinical and preclinical research in the AD and dementia field.
Wednesday, July 25 | 2 – 3:30 p.m.
Rashid Dean, Giovanni Frisoni and Karl Herrup will each summarize the Emerging Concepts in Basic Science sessions that took place on Sunday through Tuesday. Audience questions and panelist discussion in response to these questions is the main format of this session.