From behavioral studies on learning and memory to sleep-wakefulness, 2023 was a year full of researchers uncovering interesting insights into the brain using Inscopix miniscopes. Did you know that the Inscopix community is illuminating the neurons responsible for REM sleep or performing experiments on contextual fear conditioning and discovering breakthroughs for diseases like Alzheimer’s? These findings were created with Inscopix miniscope platforms and offer a glimpse into the amazing research that scientists are conducting around the world.
We are happy to announce that we compiled a noteworthy collection of scientific papers from 2023 using Inscopix miniscopes along with other novel neurotechnologies for this blog. So, sit back and enjoy your time learning about some impressive neuroscience research!
Disease and Therapeutics
Recent advancements in in vivo imaging hold significant promise for the development of new therapeutics. Utilizing nVista, Parker, et al. from Northwestern University, published in Nature Neuroscience, revealed the significance of monitoring D1-SPN activity as a promising new preclinical biomarker for assessing antipsychotic efficacy. They describe their experimental approach as follows: “Because antipsychotics bind many different receptors, understanding how they modulate the function of neural circuits involved in psychosis could provide a more meaningful understanding of their mechanism. Due to its large-scale and cell-type specificity, in vivo imaging is well suited to provide these physiological insights. Using miniature microscopes to image D1-SPN and D2-SPN Ca2+ activity in vivo, we and others showed that D1-SPNs and D2-SPNs equally co-activate in spatially clustered ensembles and scale their activity with locomotor speed.” This study has profound implications for determining the best treatments for various brain diseases.
If you’re interested in learning more, our Lead Translational Scientist Jonathan Zapata at Inscopix has written a comprehensive blog post on this article.
Sleep and Wakefulness
Unilateral Optogenetic Stimulation of Lhx6 Neurons in the Zona Incerta Increases REM Sleep
This publication can trace its roots back to 1918 when the influenza pandemic helped researchers locate regions of the brain that are responsible for being awake or asleep. It wasn’t until 1953 that a concerted effort identified the brain neurons underlying different sleep states (wake, non-REM, and REM). Now, fast forward to August of 2023, Shiromani et al. Medical University of South Carolina published in Sleep, used Inscopix’s nVista and nVoke miniscope systems to focus on the Zona Incerta (ZI) to investigate the neurons and circuits responsible for the switch between being awake and asleep. Using several techniques including optogenetics, they examined the activity of neurons containing Lhx6, a transcription factor that identifies a subtype of GABA neurons in the ZI. They found that a subset of these GABA-Lhx6 neurons in one-half of the brain can be manipulated to induce REM sleep. Their work offers important insights into the local nodes responsible for the shifting between wake-sleep states.
Sexual Behavior/Reward
Touch neurons underlying dopaminergic pleasurable touch and sexual receptivity
“Despite the centrality of socially rewarding touch in our daily lives, the neurons in the skin that detect social touch and shape the valence of perception generated in the brain remain unknown.” This was an important underlying motive for Ishmail Abdus-Saboor’s research team, at Columbia University. This study published in Cell, investigated whether sensory neurons marked by the Mrgprb4Cre mouse line were important for engaging the mesolimbic reward pathway. Using a combination of mouse genetics, slice electrophysiology, circuit tracing, behavioral paradigms, and in vivo brain imaging with the Inscopix nVista system, this group explored the skin-to-brain circuits responsible for mediating the rewarding aspect of social touch. Their revelation about the neurons responsible for sexual receptivity and dopamine release in the brain holds great promise for future studies in reward perception.
Pain
Identification of an essential spinoparabrachial pathway for mechanical itch
In this study, Acton, et al. from The Salk Institute for Biological Studies published in Neuron, wanted to explore the distinct populations of spinal inhibitory neurons responsible for mechanical and chemical itch. Itching is a protective mechanism in healthy animals but the responsible ascending pathways transmitting sensory information to the brain are still not fully understood. Using a variety of techniques including in vivo cellular resolution calcium imaging with nVista, electrophysiology, and behavioral testing, this group identified an essential population of spinoparabrachial (SPB) neurons for mechanical itch transmission from the spinal cord to the parabrachial nucleus (PBN). Interestingly, this distinction between mechanical and chemical itch pathways becomes blurred in chronic itch. This investigation on the pathways responsible for itching offers useful new data for understanding this protective response in animals.
Action Learning
Emergence of task-related spatiotemporal population dynamics in transplanted neurons
Loss of neurons and connections are the direct cause of neurological impairments from brain-damaging events such as a stroke. However, critical research gaps remain in developing methods or approaches for long-term monitoring and modulation of transplanted neurons as they integrate into damaged host networks. In this novel paper, Ganguly et al. from the University of California San Francisco published in Nature Communications, introduced a comprehensive approach utilizing nVoke for long-term monitoring and manipulation of transplanted embryonic cortical neurons, including tracking neurons expressing GCAMP and assessing graft vessel perfusion via real-time blood flow imaging, over three months. This action-learning approach and their toolbox of microscopy techniques pave the way for understanding more clearly how neural transplants can better restore neural network dynamics after injury.
Learning and memory
Control of contextual memory through interneuronal α5-GABAA receptors
γ-aminobutyric acid type A receptors (GABAARs) mediate inhibitory synaptic transmission in the brain and are the target of a wide variety of clinically important agents that impair memory. These impairments are either an undesired side effect, e.g., sedative-hypnotics, anxiolytics, anticonvulsants, or have a primary goal as general anesthetics. In this paper, Pearce, et al. from the University of Wisconsin-Madison published in PNAS Nexus, dive into the contributions of α5-GABAARs on interneurons versus pyramidal neurons by studying the effects of etomidate, a prototypical general anesthetic, on contextual fear conditioning. Using nVoke, researchers were able to recognize the importance of α5-GABAARs on interneurons as essential components of hippocampal memory machinery. These findings hold promise for advancing the development of targeted neurotherapeutics and managing various neurological disorders, such as Alzheimer’s disease, autism, depression, and schizophrenia.
Topics: Miniscope, Calcium Imaging, nVista, nVoke, Antipsychotics, Pain, Memory
Melissa Martin is the Life Science Writer for Bruker Fluorescence Microscopy with a B.S. in Zoology and Life Sciences Communication from the University of Wisconsin-Madison. She is passionate about a wide variety of scientific topics, including brain-neuron behavior and wildlife ecosystem adaptations during climate change. She enjoys conducting interviews and reading about researchers’ work in cell biology, neuroscience, and genomics and hopes to continue to share what she learns with others in an exciting and positive way.