
Hidden network of enzymes accounts for loss of brain synapses in Alzheimer's The discovery of abnormal chemical reactions may lead to novel targets for drugs that treat neurodegenerative diseases.
December 03, 2020
LA JOLLA, CA A new study on Alzheimer's disease by Scripps Research scientists has revealed a previously unknown biochemical cascade in the brain that leads to the destruction of synapses, the connections between nerve cells that are responsible for memory and cognition.
The findings present a fresh angle for discovering drugs that treat Alzheimer's disease, which affects roughly 50 million people worldwide. The study, led by Scripps Research Professor and Step Family Foundation Endowed Chair Stuart Lipton, MD, PhD, appears in the journal Science.
This newly-discovered series of abnormal chemical events, termed protein transnitrosylation reactions, contribute to synapse loss, the main driver of memory loss and cognitive decline in Alzheimer's.
Lipton, who is also a clinical neurologist, explains that most recent attempts to develop Alzheimer's treatments have targeted the sticky protein known as beta amyloid that accumulates in the brain of patients, disrupting cell communication and causing inflammation. However, for a variety of reasons, these attempts have failed in clinical trials.
This work gives us new hope for better therapeutic targets, as the reactions we discovered are downstream of amyloid action, Lipton says. We've opened up a whole new avenue for drug development.
Lipton is no stranger to drug development for Alzheimer's and Parkinson's diseases. Drugs developed in and patented by his laboratory have led to four FDA-approved medicines for these diseases, including the widely prescribed drug, memantine (Namenda ). Much better drugs are needed, however, Lipton says.
A chemistry success story
In the new study, Lipton and his team used physical chemistry techniques to quantify how electrons participate in chemical reactions, as they suspected unknown processes may be taking place in the brain. Through this, they uncovered the entirely new series of biochemical events in nerve cells affected by Alzheimer's.
They found that small clumps of beta amyloid protein trigger excessive neuron activity and inflammation, leading to the destructive series of transnitrosylation reactions.
The process begins with excessive levels of nitrogen (N) and oxygen (O) atoms joining together as an NO group, which is then transferred to a protein building block called cysteine to regulate the activity of the protein. A series of these aberrant protein reactions cuts off energy to the brain's nerve cells by disrupting their mitochondria organelles that generate power for the cell's biochemical reactions. This eventually leads to loss of synapses connecting the nerve cells.
We were able to show that these reactions occur in brains of Alzheimer's patients, and when we prevented these reactions in the brains of animal models of the disease, we protected the synapses, Lipton says. Our findings suggest that it may be possible to intercede to reverse synapse damage in spite of plaques and tangles, he added, referring to plaques of beta amyloid and tangles of misfolded tau protein, both of which are characteristic of Alzheimer's disease.
He notes that while normal levels of NO foster memory and learning, excessive levels can build up as we age and become harmful to synapses.
With this new knowledge, we may be able to restore synaptic connections in Alzheimer's patients after extensive plaques and tangles have formed in their brains, adds Tomohiro Nakamura, PhD, senior staff scientist in the Lipton laboratory group and first author of the study.
Revealing secret connections
Lipton says that one of the team's most incredible findings was that the three enzymes discovered to pass NO to each other along a concerted chain of events, resulting in energy failure, were previously not thought to be even remotely related to one another. Each of the enzymes is important in its own right in a completely disparate normal biochemical pathway, and yet they interact under disease conditions in a novel manner to trigger intense neuronal stress and synapse damage.
This type of hidden or ghost' pathway may only become evident under disease conditions and may represent an important fundamental tenet of why we did not understand the disease process previously, Lipton says. If we do not know about a pathway, scientists cannot study its contribution to disease or develop drugs to treat it.
While many molecular biochemical pathways have been discovered, an over-reliance on this existing body of evidence can actually impede discovery of disease processes, he adds.
Hence, the most important aspect of the work is that we have to be on our guard to look for new pathways and new relationships of existing enzymes in order to understand and treat neurodegenerative disorders such as Alzheimer's, Lipton says.
In addition to Nakamura and Lipton, other authors of Non-canonical transnitrosylation network contributes to synapse loss in Alzheimer's disease, include Chang-ki Oh, Xu Zhang, Kevin Lopez, Amanda Deal, Henry Scott, Lujian Liao and John R. Yates III from Scripps Research; and Daniel Gibbs, Brian Spencer, Robert Rissman and Eliezer Masliah from the University of California, San Diego.
The work was funded by the National Institutes of Health and philanthropic support.
Neurological Disorders Molecular and Cellular Biology Lipton, Stuart
Most recent headlines
05/01/2027
Worlds first 802.15.4ab-UWB chip verified by Calterah and Rohde & Schwarz to be ...
07/10/2026
Dalet, a leading technology and service provider for media-rich organizations, today announced the latest Long-Term Supported (LTS) release of Dalet Flex. Build...
08/09/2026
Comcast Technology Solutions (CTS) has announced a multi-year agreement with A E...
08/09/2026
Spectra Logic today announced the availability of Media Insight, a new capabilit...
08/09/2026
Rogers Communications and Quebecor have announced a 12-year sublicensing agreement for French-language national NHL games beginning with the 2026-27 season. TVA...
08/09/2026
Skyline Communications and Bridge Technologies will demonstrate two integrations...
08/09/2026
Boland Communications will make the European debut of its 4K55HDR7SNB 55-inch super-narrow-bezel monitor at IBC2026 (Stand 12.C57, RAI Amsterdam, September 11-1...
08/09/2026
Ateme and Comcast Technology Solutions (CTS) have announced a collaboration comb...
08/09/2026
Haivision has joined the IBC Accelerator Media Innovation Programme as part of t...
08/09/2026
Blackmagic Design has announced price reductions on its PYXIS 6K and Cinema Camera 6K models, effective immediately through Blackmagic Design resellers worldwid...
08/09/2026
AI-Media will demonstrate its LEXI Suite at IBC2026 (Booth 5.C34, September 11-1...
08/09/2026
Bitmovin and Ad Insertion Platform (AIP) have announced the first live deploymen...
08/09/2026
Grass Valley will demonstrate story-centric media workflows at IBC2026 (Booth 9.A01, RAI Amsterdam, September 11-14), connecting newsroom production, content ma...
08/09/2026
M2A Media and Ateme have announced a partnership integrating Ateme's video processing solutions into M2A Media's MediaToAnywhere platform for live sport...
08/09/2026
Ikegami will exhibit at IBC2026 (Stand 12.A31, RAI Amsterdam, September 11-14), including a Day 1 introduction of new cameras in the UNICAM XE series. Additiona...
08/09/2026
Broadcast industry analysts will be gathering plenty of insights at the 2026 IBC Show this weekend in Amsterdam, but Caretta Research has offered up some though...
08/09/2026
SENSHI and DAZN have announced a global broadcast partnership that will bring SENSHI's live events free to viewers in more than 200 markets. The partnership...
08/09/2026
New architecture built with Evertz will bring 4K HDR to Monday Night Football, N...
08/09/2026
Built for rap producers, by rap producers
Sauceware Audio, the independent plug-in company founded by Grammy-nominated producer Jacob (Travis Scott, 21 Sava...
08/09/2026
Classic Sound Techniques design revived
Warm Audio's latest release delivers a meticulous recreation of the preamp circuitry employed by the Sound Techn...
08/09/2026
Latest soft synth inspired by the Memorymoog
XILS Lab have just launched a software instrument that draws its inspiration from Moog's iconic Memorymoog,...
08/09/2026
The Airport Chaplain takes off as SBS's biggest launch of 2026
8 September, 2026
Media releases
1.67 million viewers on National Total TV to date
Best...
08/09/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
08/09/2026
Mo-Sys, the world-leading developer of virtual production, camera robotics and image tracking technology, has completed a business restructuring, which has incl...
08/09/2026
New York, September 8, 2026 The TSAmediaHUB audiovisual contribution and distribution infrastructure developed by Telef nica's Audiovisual Services area re...
08/09/2026
Expanded Riyadh operation brings Asharq and Thmanyah services together on a resilient on-premises Pebble platform.
Pebble, the leading automation, content mana...
08/09/2026
Techex, a pioneering leader in live video workflows, will showcase its broadest software feature set to date at IBC 2026 (Stand 2.B45), extending its lead in so...
08/09/2026
Visitors to Grass Valley's booth at IBC2026 will be introduced to new Framelight X capabilities that connect content acquisition, management, editing and pu...
08/09/2026
BCNEXXT will showcase the latest evolution of Vipe at IBC2026 (Stand 2.B09), introducing a series of innovations designed to deliver higher-quality audience exp...
08/09/2026
Bitmovin, a provider of video streaming solutions, has partnered with Ad Insertion Platform (AIP), a leading innovator in advanced ad insertion technologies, to...
08/09/2026
Brainstorm, a leading manufacturer of real-time graphics and augmented and virtual production, is announcing a major package of enhancements to its Suite 7 soft...
08/09/2026
Big Blue Marble is supporting TDF, French infrastructure and network operator, broadcasting Digital Terrestrial Television (DTT) and radio services, as a techno...
08/09/2026
Agents work inside a single production environment, from incoming wire copy to a live studio show...
08/09/2026
Building on their strategic partnership, Ceeblue and Layercake make the unthinkable possible: scalable sub-second streaming over standard DRM, SSAI, and CDN wor...
08/09/2026
Brainstorm, a leading manufacturer of real-time graphics, augmented and virtual production, is completing the environment for fast-paced broadcast production wi...
08/09/2026
A SaaS portfolio built to work together, helping operators grow audiences, monetise smarter and run leaner, on their own terms
At IBC 2026 (stand 1.B49) Synam...
08/09/2026
Accedo, global provider of video streaming software and services, has been selected by PlayOn Sports, a national leader in high school sports technology, to exp...
08/09/2026
LiveU, the leader in live IP-video solutions, is enabling The Associated Press to take global newsgathering to the next stage with intelligent connectivity and ...
08/09/2026
Mediagenix, a global leader in smart content solutions to profitably connect the right content to the right audience, today announced the latest evolution of it...
08/09/2026
Compact, power-efficient X Platform performance brings broadcast-grade reliability and ultra-low latency to space-constrained remote production (REMI) workflows...
08/09/2026
Zixi, the leader in live video delivery and workflow orchestration, and Kiloview, a leading provider of professional IP video encoding and decoding solutions, t...
08/09/2026
Collaboration gives content owners scalable CDN capacity and broadcasters enhanced flexibility, including for C-band transition planning
Quortex today announce...
08/09/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
08/09/2026
Telos Alliance and Pluxbox Announce Dynamic Media Facility Integration Partnersh...
08/09/2026
J nger Audio Showcases Industry-First S-ADM Cloud Workflow at IBC 2026
Search
Dolby, MainConcept, Techex and J nger Audio will showcase the industry's ...
08/09/2026
Tuesday 8 September 2026
Sky Go gets a major upgrade for Sky Glass and Sky Stream customers
Today, Sky launches a new version of the Sky Go app for Sky Glass ...
08/09/2026
Documentary thriller simulating a Russian attack on UK soil will culminate in a live final episode reuniting the playersTuesday 8 September 2026
Trailer releas...
08/09/2026
Tuesday 8 September 2026
Jamie Demetriou and Amelia Dimoldenberg to host next t...
08/09/2026
Wuppertal September 8, 2026
Riedel Introduces New OnAir Headset PlatformRiedel Communications today announced the launch of its new OnAir headset platform, a...