Scientists have taken a step forward towards understanding the communication between neurons via neuropeptides. They have created the first wireless map of a worm’s nervous system.
The map indicates where each neuropeptide and its corresponding receptor functions in the nervous system of the animal. It details 31,479 neuropeptide connections between the worm’s 302 neurons. Neuropeptide networks can be compared to a wireless connectome since they facilitate communication between neurons that are not physically adjacent. A connectome is a detailed schematic of the neurological networks and neurons that comprise an organism’s brain.
The study was conducted by Dr William Schafer and Ph.D. student Lidia Ripoll-Sánchez, both of the Medical Research Council Laboratory of Molecular Biology in Cambridge in the UK, led the work, together with Petra Vértes of Cambridge University and Isabel Beets from KU Leuven in Belgium.
Scientists studied C. elegans worms. Despite having a very simple structure, C. elegans shares many of the fundamental biological traits that developmental biologists employ extensively and that are crucial to problems in human biology.
It is possible to use C. elegans’ multi-layered connectome as a “model” to comprehend better the intricate networks that comprise bigger neurological systems, such as the human brain.
In addition to creating the first thorough map of neuropeptide signaling in an entire animal, scientists also discovered that the network of the C. elegans wireless neuropeptide network differs from that of wired connections. They feature distinct important neurons, or hubs, and are denser and more decentralized.
Additionally, the nervous system’s wireless network links sections cut off from the wired network.
Dr Schafer said, “Neuropeptides and their receptors are among the hottest new targets for neuroactive drugs. For example, the diabetes and obesity drug Wegovy targets the receptor for the peptide GLP-1. But how these drugs act in the brain at the network level is not well-understood.”
“The structure of neuropeptide networks suggests that they may process information differently than synaptic networks. Understanding how this works will not only help us understand how drugs work but also how our emotions and mental states are controlled.”
“The idea of mapping these wireless networks has been one of our goals for a long time, but only now have the right combination of people and resources come together to make this possible.”
Scientists combined biochemical, anatomical, and gene expression datasets. They then used them to determine which neurons can communicate with each other using specific neuropeptide signals.
After building this network, they used mathematical models to understand the relationships between these neuropeptide signals. They also identified critical features and neurons with essential roles in linking different network parts.
Jo Latimer, Head of Neurosciences and Mental Health at the Medical Research Council (MRC), said, “Not only have they worked out which neuropeptides act where in the animal’s nervous system, they have discovered that the network is complex, but organized, with an information processing circuit within it.”
“This is a further important step forward in understanding how brains and nervous systems work, and this increased understanding may potentially lead to the future development of targeted therapies for various conditions.”
The next task will be to determine whether the principles that govern the organization of neuropeptide networks in worms also hold in larger brains.
Currently, scientists are mapping wireless neuropeptide networks in fish, octopuses, mice, and perhaps humans in collaboration with other scientists.
The details regarding the research were published in the journal Neuron.