Speaker : JOSÉ LÓPEZ-BARNEO – Institute of Biomedicine, University of Seville Medical School, Seville, Spain
Title : “Oxygen sensing and stem cells in the carotid body. Role in adaptation to hypoxia.”
Oxygen (O2) is required for most forms of life on Earth and, therefore, adaptation to hypoxia is a major biological challenge.
In mammals, peripheral chemoreceptors are able to detect changes in O2 tension and in response to hypoxia can elicit fast
cardiovascular reflexes (i.e. hyperventilation and sympathetic activation), which increase O2 uptake and its distribution to the tissues.
The main arterial chemoreceptor is the carotid body (CB), a small neurosecretory organ located at the bifurcation of the carotid artery.
Although the field of arterial chemoreception has advanced considerably in the last decades, the precise mechanisms whereby acute
changes in O2 tension are detected by chemoreceptor cells have remained elusive. Recent data supporting a major role of mitochondrial
complex I in acute O2 sensing will be discussed. An intriguing property of the CB is that it can grow several times during exposure to
sustained (chronic) hypoxia. This occurs thanks to the existence in the adult CB of a collection of neural crest-derived stem cells.
CB progenitors form “chemical synapses” with mature neuron-like glomus cells which, when are activated by hypoxia, instruct
stem cells to proliferate and differentiate. The role of CB stem cell niche in adaptation/misadaptation to hypoxia will be discussed.
Note from Colin Nurse (host)
Professor José López-Barneo MD, PhD, Institute of Biomedicine, University of Seville Medical School, Seville, Spain, will be visiting
the Department of Biology and presenting a seminar on July 20th 2016 at 4 pm in HSC 4E20. José is an outstanding researcher in the field
of oxygen sensing and has done some of the best work on O2 and CO2/pH chemoreception using a variety of experimental techniques
including electrophysiology, Ca-imaging, amperometry, molecular biology, & transgenic models. His most recent work includes:
(i)models of mitochondrial complex I knockout leading to loss of O2 sensing in chemosensory cells; and (ii) seminal papers published
in Cell on stem cells of glial origin in a chemosensory organ (i.e. the carotid body). In addition to Cell, his work has been published in
top journals including: Science, Nature Neuroscience, Neuron, EMBO J, PNAS, Cell Metabolism, New Eng J Medicine, J. Neurosci.,
J Physiol. etc.