will take place on Tuesday, June 23, 2020 from 17:15 hours to 18:15 hours in CBBM Building, Ground Floor, Seminar Room B1/B2 (Levi-Montalcini).
Host: Prof. Dr. Henrik Oster
Institute of Neurobiology
University of Lübeck
Abstract
Life on earth has evolved in the 24h light-dark cycle, which is a one of the most powerful signals for the circadian timing system which optimizes timing in physiological processes, including gene regulation, hormone secretion, insulin signaling, immune function, cognitive function, and sleep/wake. In my talk, I will provide an overview of the effects of light on human health, with a focus on those thought to be mediated by the circadian timing system. I will present population-level and individual level data supporting the hypothesizes that light exposure is, even in the context of modern, self-selected light exposure patterns, fundamental for circadian and sleep regulation, health, and safety. As part of my presentation, I will also propose novel, data-driven approaches to classification of individual light exposure patterns, such k-means and hierarchical clustering, and argue that machine learning can help quantify complex light signals in real-world settings. Finally, I will address and review methodological challenges when collecting individual-level light exposure profiles in the real world, and outline future steps necessary to build evidence to design novel light-based interventions to improve human health.
The cause of obesity, insulin resistance and type 2 diabetes (T2D) is multifactorial including genetic, epigenetic and environmental factors. In order to identify genes and pathways that are contributing to obesity and dysregulated in T2D we combined linkage studies with transcriptome data of lean and obese as well as of diabetes-prone and diabetes-resistant mice. We identified more than 290 QTL for obesity and 190 QTL for diabetes-related traits. I will introduce the approach of positional cloning for the identification of new disease genes. In addition, I will speak about the role of cilia-annotated genes which exhibit a differential expression in islets of control and diabetic mice and human and show their effects on cell-cycle progression.
In the second part, I will present data on the identification of epigenetic alterations contributing to body weight gain, fatty liver and diabetes. For this we use genetically identical mice which react with different body weight gain on a high fat diet, or which differ in the develop of diabetes. We identified several genes to be differentially expressed in the liver due to changes in the DNA methylation. Up to know we confirmed similar changes for the human DPP4 and IGFBP2 genes in liver and blood cells, respectively. Thus, our data indicate that specific mouse models are ideal to identify new diseases genes and epigenetic alterations also relevant for human.
Biosketch
Céline Vetter studied psychology at the Université Louis Pasteur in Strasbourg (France) from 2001 to 2004, followed by a Master of Science in neuro-cognitive psychology at Ludwig-Maximilian-University (LMU) in Munich, Germany. After a postgraduate research year at Warwick University (UK), Dr. Vetter completed her PhD at the LMU, focusing on human chronobiology and sleep at the workplace in 2011. She stayed on as a postdoctoral research association for 2 more years, where she led efforts to implement a chronotype-adjusted shift schedule in the steel industry to promote sleep and reduce circadian misalignment, and ultimately improve health. Funded by the DFG, she joined the Channing Division of Network Medicine at Brigham and Women’s Hospital and Harvard Medical School (BWH/HMS) in Boston in 2014 to learn epidemiological methods with the ultimate goal to advance our understanding of the long-term consequences of circadian and sleep disruption on health. In 2016, she was promoted to junior faculty at BWH and HMS and successfully obtained funding as a Co-Investigator by the National Institutes of Health (NIH). Since 2016, she is an Associate Scientist with the Broad Institute of MIT and Harvard. In 2017, Dr. Vetter accepted a tenure-track Assistant Professor position at the University of Colorado Boulder, where she now directs the Circadian and Sleep Epidemiology Laboratory. Her work is funded by the NIH, and featured in top-tier journals, including JAMA, JACC, Diabetes Care, Nature Communications, and Current Biology. To date, she has authored >40 original research peer-reviewed articles and >15 reviews, editorials, and invited commentaries (h-index: 20). At CU Boulder, Dr. Vetter teaches undergraduate and graduate level courses, incl. Introduction to Epidemiology, Data Literacy for Biomedical Research, and Graduate Statistics. She also is actively engaged in service, for example as Chair of the Society for Research on Biology Rhythms Public Outreach Committee, Associate Editor to the Journal of Biological Rhythms and Clocks & Sleep, Member of the Sleep Research Society’s Circadian Rhythms Task Force, and peer mentor to postdoctoral fellows and junior faculty.
