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Biology subjects

Suh, G. S. B.

Publications and source records attributed to Suh, G. S. B..

4 recordsLinked to original sources

Splanchnic-spinal transmission of gut-initiated α-synucleinopathy

Gut-initiated -synucleinopathy is proposed to spread from the gastrointestinal tract to the CNS, contributing to Parkinson's disease (PD), but whether routes beyond the vagus nerve are involved remains unclear. Using complementary intracolonic rotenone and gastroduodenal -synuclein PFF models, we combined pathway-specific surgical interruption with longitudinal behavioral analysis and anatomical mapping of pathological -synuclein. In the intracolonic rotenone model, interruption of the prevertebral ganglia/splanchnic-spinal axis more strongly attenuated behavioral deficits and -synuclein pathology than vagotomy. In the gastroduodenal PFF model, both vagal and splanchnic-spinal pathways contributed to pathology propagation. Early after PFF inoculation, pathological -synuclein was detected in peripheral neural structures associated with both routes. Consistent with these findings, spinal pathology was evident in human PD. Together, these results identify the splanchnic-spinal pathway as a key component of body-first Parkinson's disease, broadening current models of peripheral-to-central disease progression and informing efforts to target early peripheral disease progression.

neuroscience↗

Evaluation of mouse behavioral responses to nutritive versus nonnutritive sugar using a deep learning-based 3D real-time pose estimation system

Animals are able to detect the nutritional content of sugar independently of taste. When given a choice between nutritive sugar and nonnutritive sugar, animals develop a preference for nutritive sugar over nonnutritive sugar during a period of food deprivation1-5. To quantify behavioral features during an episode of licking nutritive versus nonnutritive sugar, we implemented a multi-vision, deep learning-based 3D pose estimation system, termed the AI Vision Analysis for Three-dimensional Action in Real-Time (AVATAR)6. Using this method, we found that mice exhibit significantly different approach behavioral responses toward nutritive sugar versus nonnutritive sugar even before licking a sugar solution. Notably, the behavioral sequences during approach toward nutritive versus nonnutritive sugar became significantly different over time. These results suggest that the nutritional value of sugar not only promotes its consumption, but also elicits distinct repertoires of feeding behavior in deprived mice.

animal behavior and cognition↗

Control of feeding by Piezo-mediated gut mechanosensation in Drosophila

Across animal species, meals are terminated after ingestion of large food volumes, yet underlying mechanosensory receptors have so far remained elusive. Here, we identify an essential role for Drosophila Piezo in volume-based control of meal size. We discover a rare population of fly neurons that express Piezo, innervate the anterior gut and crop (a food reservoir organ), and respond to tissue distension in a Piezo-dependent manner. Activating Piezo neurons decreases appetite, while Piezo knockout and Piezo neuron silencing cause gut bloating and increase both food consumption and body weight. These studies reveal that disrupting gut distension receptors changes feeding patterns, and identify a key role for Drosophila Piezo in internal organ mechanosensation.

neuroscience↗

Sensory Detection of Aversive and Appetitive Stimuli by CRF neurons

Corticotropin-releasing factor (CRF), which is released from the paraventricular nucleus (PVN) of the hypothalamus, is essential for mediating stress response by activating the hypothalamic-pituitary-adrenal (HPA) axis. CRF-releasing PVN neurons receive inputs from multiple brain regions that convey stressful events, but their rapid neuronal dynamics on the timescale of behavior remain unknown. Here, our optical recordings of PVN CRF neuronal activity in freely behaving mice revealed that PVN CRF neurons are activated immediately by a range of stress-inducing aversive stimuli, including predator odor. By contrast, CRF neuronal activity starts to drop within a second of exposure to appetitive stimuli, such as food. These findings suggest that PVN CRF neurons receive real-time information about aversive and appetitive stimuli. Their role in mediating the sensory detection and regulating the neuroendocrine axis resembles those of AgRP/NPY neurons and SFO neurons that regulate neurophysiology responses and mediate sensory detection of food and water.

neuroscience↗