Researchers Use "zap-and-freeze" Technique To Watch Hard-to-see Brain Cell Communications

Researchers astatine Johns Hopkins Medicine opportunity they person utilized a "zap-and-freeze" exertion to watch hard-to-see encephalon compartment communications successful surviving encephalon insubstantial from mice and humans.

Findings from nan caller experiments, supported by nan National Institutes of Health and published Nov. 24 successful Neuron, could perchance thief scientists find nan guidelines causes of nonheritable forms of Parkinson's disease, nan researchers say.

Sporadic cases of Parkinson's illness relationship for astir cases of nan neurodegenerative disorder, according to nan Parkinson's Foundation. The information is marked by disruptions to nan signaling constituent betwixt 2 encephalon cells. That relationship point, known arsenic a synapse, is notoriously difficult to study, says Shigeki Watanabe, Ph.D., subordinate professor of compartment biology astatine Johns Hopkins Medicine, who led nan research.

We dream this caller method of visualizing synaptic membrane dynamics successful unrecorded encephalon insubstantial samples tin thief america understand similarities and differences successful nonheritable and heritable forms of nan condition."

Shigeki Watanabe, Ph.D., subordinate professor of compartment biology, Johns Hopkins Medicine

Eventually, he says, this attack could thief lead to nan improvement of treatments for nan neurodegenerative disorder.

Understanding guidelines causes of Parkinson's disease

In patient brains, synaptic vesicles, aliases message-carrying bubbles wrong encephalon cells, thief transportation accusation from compartment to compartment successful a process cardinal to accusation processing, learning and forming memories. Understanding this process is captious for identifying wherever cellular connection breaks down successful neurodegenerative conditions, Watanabe says.

Previously, Watanabe helped create nan zap-and-freeze method to let for a person look astatine synaptic membrane movements (these results were published successful 2020 successful Nature Neuroscience). Essentially, nan method involves utilizing an electrical beat to stimulate surviving encephalon insubstantial and past freezing nan tissues quickly to seizure compartment activity for particle microscopy observation.

In a study published earlier this twelvemonth successful Nature Neuroscience, Watanabe utilized nan attack successful nan brains of genetically engineered mice to understand really a cardinal protein, intersectin, keeps synaptic vesicles successful a peculiar location wrong a encephalon compartment until they are fresh to beryllium released to activate a neighboring encephalon cell.

For nan caller study, nan researchers utilized samples from nan brains of normal mice arsenic good arsenic surviving cortical encephalon insubstantial sampled pinch support from six individuals undergoing surgical curen for epilepsy astatine The Johns Hopkins Hospital. The surgical procedures were medically basal to region lesions from nan brain's hippocampus.

Working pinch scientists Jens Eilers and Kristina Lippmann astatine Leipzig University successful Germany, nan researchers first validated nan zap-and-freeze attack by watching calcium signaling, a process that triggers neurons to merchandise neurotransmitters successful surviving rodent encephalon tissues.

Next, nan scientists stimulated neurons successful rodent encephalon insubstantial pinch nan zap-and-freeze attack and observed wherever synaptic vesicles fuse pinch encephalon compartment membranes and past merchandise chemicals called neurotransmitters that scope different encephalon cells. The scientists past observed really rodent encephalon cells recycle synaptic vesicles aft they are utilized for neuronal communication, a process known arsenic endocytosis that allows worldly to beryllium taken up by neurons.

The researchers past applied nan zap-and-freeze method to encephalon insubstantial samples from group pinch epilepsy, and observed nan aforesaid synaptic vesicle recycling pathway operating successful quality neurons.

In some rodent and quality encephalon samples, nan macromolecule Dynamin1xA, which is basal for ultrafast synaptic membrane recycling, was coming wherever endocytosis is thought to hap connected nan membrane of nan synapse.

"Our findings bespeak that nan molecular system of ultrafast endocytosis is conserved betwixt mice and quality encephalon tissues," Watanabe says, suggesting that nan investigations successful these models are valuable for knowing quality biology.

In early experiments, Watanabe says he hopes to leverage nan zap-and-freeze method to study synaptic vesicle dynamics successful encephalon insubstantial samples taken pinch support from patients pinch Parkinson's illness undergoing heavy encephalon insubstantial stimulation. 

Funding support for this investigation was provided by nan National Institutes of Health (U19 AG072643, 1DP2 NS111133-01, 1R01 NS105810-01A1, R35 NS132153, S10RR026445), Howard Hughes Medical Institute, Kazato Foundation, American Lebanese Syrian Associated Charities, Marine Biological Laboratory, Leipzig University, Roland Ernst Stiftung, Johns Hopkins Medicine, Chan Zuckerberg Initiative, Brain Research Foundation, Helis Foundation, Robert J Kleberg Jr and Helen C Kleberg Foundation, McKnight Foundation, Esther A. & Joseph Klingenstein Fund, and nan Vallee Foundation.

In summation to Watanabe, different scientists who contributed to this activity see Chelsy Eddings, Minghua Fan, Yuuta Imoto, Kie Itoh, Xiomara McDonald, William Anderson, Paul Worley and David Nauen from Johns Hopkins, and Jens Eilers and Kristina Lippmann from Leipzig University, Germany.