PET allows noninvasive visualization of several physiological, neurochemical, and pharmacological processes within patients. Application of PET in the brain has been limited due to a lack of radiotracers that label specific neurons or regions. In this episode, Jacob Hooker, Mark Alberts, and Genevieve C. Van de Bittner describe the discovery and characterization of [11C]GV1-57 (Neuroflux), which specifically labels mature olfactory sensory neurons in the olfactory epithelium. This radiotracer has potential as a powerful tool for monitoring olfactory neurogenesis under both normal and disease states.
The hormone kisspeptin is essential for reproductive function, an effect that is mediated by its actions in the hypothalamus. Recent studies suggest that kisspeptin and its receptor are also expressed in other regions of the brain; however, little is known about the effects of this hormone in the brain in regions outside of the hypothalamus. In this episode, Waljit Dhillo and colleagues evaluate limbic system-specific effects of kisspeptin administration in healthy male volunteers. The data from this study indicate that kisspeptin action in the limbic system mediates sexual and emotional brain processing.
Aminoglycoside antibiotics can damage the hair cells of the inner ear, leading to hearing loss and balance disorders. Improved treatment paradigms have reduced the risk of adverse effects associated with these antibiotics, but permanent inner ear damage is still common. Hair cells are susceptible to damage because of their tendency to take up and retain aminoglycosides, whereas less vulnerable cells do not accrue aminoglycosides after exposure. To better understand the mechanisms that contribute to aminoglycoside toxicity, David Raible’s lab at the University of Washington imaged fluorescently-labeled aminoglycosides in the hair cells of live zebrafish. They found that the degree of aminoglycoside-induced toxicity was linked to how rapidly the antibiotic was distributed into lysosomes, suggesting that monitoring the kinetics of lysosomal delivery may be an effective way to evaluate different aminoglycoside treatment paradigms.
In the accompanying video, a time-lapse of zebrafish hair cells (green) shows the transit of fluorescently-labeled aminoglycosides (red) from the intracellular space into lysosomes. At the beginning of the video, aminoglycosides are visible as a diffuse pool in the cytosol. Within 20 minutes, the diffuse signal decreases as aminoglycosides merge into puncta, indicating their uptake into lysosomes.
Though Bruce Alberts is well known for his work on the biochemistry of DNA replication and as the editor-in-chief of Science, he is also recognizable as the author of the seminal biology textbook Molecular Biology of the Cell. Alberts served as the president of the National Academy of Sciences for over a decade and is currently a professor at University of California, San Francisco. This year, his dedication to advancing science policy and education was recognized with the Lasker-Koshland Special Achievement Award. JCI’s editor-at-large Ushma Neill sat down with Alberts to talk about how his background in science shaped his later work as an educator and leader in science policy. They also discuss the challenges of improving science education through writing, editing, and policy making.
Retinitis pigmentosa (RP) is a heterogeneous genetic disorder that is characterized by a progressive loss of photoreceptors that results in deterioration of vision. While gene therapy has shown promise for some forms of RP, over 60 genes have been implicated in this disorder; therefore, non-gene-targeted therapies are of great interest. In this episode, Stephen Tsang and colleagues discuss their study, which shows that upregulation of glycolytic flux, via targeted downregulation of sirtuin 6, in rod photoreceptors improves photoreceptor survival and preserves vision in a mouse model of RP. As this strategy is not gene-specific, it may be beneficial for a range of neurodegenerative disorders.