
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 ...
01/06/2026
January 6 2026, 05:30 (PST) Dolby Sets the New Standard for Premium Entertainment at CES 2026
Throughout the week, Dolby brings to life the latest innovatio...
01/05/2026
January 5 2026, 18:30 (PST) NBCUniversal's Peacock to Be First Streamer to ...
01/04/2026
January 4 2026, 18:00 (PST) DOLBY AND DOUYIN EMPOWER THE NEXT GENERATON OF CREATORS WITH DOLBY VISION
Douyin Users Can Now Create And Share Videos With Stun...
27/01/2026
eds3_5_jq(document).ready(function($) { $(#eds_sliderM519).chameleonSlider_2_1({ content_source:......
27/01/2026
Nielsen will continue to drive growth and provide local audience measurement
in...
27/01/2026
Share Share by:
Copy link
Facebook
X
Linkedin
Pinterest
Bluesky
Email...
27/01/2026
Share Share by:
Copy link
Facebook
X
Linkedin
Pinterest
Bluesky
Email...
27/01/2026
Share Share by:
Copy link
Facebook
X
Linkedin
Pinterest
Bluesky
Email...
27/01/2026
Amagi Media Labs Limited, the only cloud-native SaaS provider offering end-to-end solutions across live production, content preparation, distribution, and monet...
27/01/2026
Miri Technologies Inc. today unveiled its V410 live 4K video encoder/decoder for streaming, IP-based production workflows and AV-over-IP distribution. Designed ...
27/01/2026
The Paul E. Tsongas Center at UMass Lowell in Massachusetts has chosen Ikegami cameras for incorporation into its broadcast-quality television production facili...
27/01/2026
SipRadius, specialists in secure, low latency media transport, will show the pro AV community its end-to-end solution for high quality content distribution and ...
27/01/2026
Hiltron will highlight the fruits of its 45-plus years of experience in satellite communications system integration and product development at the annual GovSat...
27/01/2026
Klvr will demonstrate how its Charger Pro solution is delivering cost reduction and performance benefits for live entertainment and pro AV markets at ISE 2026 (...
27/01/2026
Amino, a global media technology leader in enterprise video and digital signage, today announced that its Integrated Systems Europe (ISE) 2026 booth (4N700) wil...
27/01/2026
ANI, India's leading news agency and a major content provider across the Asia Pacific region, today announced a significant expansion of its long standing p...
27/01/2026
Independent analysis confirms faster encoding, lower CPU usage, and improved perceptual quality compared to CBR and CRF
VisualOn, a leader in multimedia playba...
27/01/2026
Share Share by:
Copy link
Facebook
X
Linkedin
Pinterest
Bluesky
Email...
27/01/2026
Share Share by:
Copy link
Facebook
X
Linkedin
Pinterest
Bluesky
Email...
27/01/2026
Share Share by:
Copy link
Facebook
X
Linkedin
Pinterest
Bluesky
Email...
27/01/2026
Share Share by:
Copy link
Facebook
X
Linkedin
Pinterest
Bluesky
Email...
27/01/2026
New agreement for uninterrupted UHF connectivity for Australian Defence Force through 2033, With Options Extending to 2041
Luxembourg, January 13, 2026 - Satel...
27/01/2026
RT Supporting the Arts is delighted to support a dynamic programme of cultural events taking place across Ireland this February. From visual art, film, music, ...
26/01/2026
Music videos play a huge part in how fans connect with their favorite songs, but...
26/01/2026
NAIDOC launches 2026 theme 50 Years of Deadly , marks major milestone
25 January, 2026
Media releases
The National NAIDOC Committee has today unveiled its...
26/01/2026
Share Share by:
Copy link
Facebook
X
Linkedin
Pinterest
Bluesky
Email...
26/01/2026
Share Share by:
Copy link
Facebook
X
Linkedin
Pinterest
Bluesky
Email...
26/01/2026
Share Share by:
Copy link
Facebook
X
Linkedin
Pinterest
Bluesky
Email...
26/01/2026
Share Share by:
Copy link
Facebook
X
Linkedin
Pinterest
Bluesky
Email...
26/01/2026
Advanced Systems Group (ASG) today announced an exclusive partnership with Nu Studio, the company behind the first modular, portable studio designed for immersi...
26/01/2026
OpenDrives, the leader in high-end video data management and workflow solutions, today announced an add-on investment to its previous funding rounds, led by IAG...
26/01/2026
SmallHD today announced a major update to its award-winning PageOS software, introducing Fleet Control, Portrait Mode, expanded Camera Control features, and Dow...
26/01/2026
Whether rigging a PTZ on a truss, sliding a Blackmagic camera across a mezzanine railing, or capturing the mayhem from inside a drum, Filipic delivers visuals t...
26/01/2026
26 Jan 2026
VEON Unveils the New Beeline Uzbekistan Network Operations Center, ...
26/01/2026
Bookish is created by and stars Mark Gatiss
Images available HERE
Following th...
26/01/2026
Monday 26 January 2026
New Sky Original Series explores Entertainment Juggernaut, The X Factor
Sky today confirmed it has greenlit a premium, definitive docum...
26/01/2026
Monday 26 January 2026
Sky confirms major investment to transform Livingston ca...
26/01/2026
Back to All News
Netflix Unveils Official Trailer for Salvador
Entertainment
26 January 2026
GlobalSpain
Link copied to clipboard
DISCOVER THE TRAILER
DO...
26/01/2026
Back to All News
Netflix Presents Our 2026 Series and Films and Announces New Projects
Entertainment
26 January 2026
GlobalSpain
Link copied to clipboard
...
26/01/2026
Back to All News
Made in Louisiana: People We Meet on Vacation' Lights Up New Orleans
Emily Bader and Tom Blyth film on Royal Street in New Orleans' ...
26/01/2026
LinkedIn Gives Professionals the Edge with Verified Skills and Tools to Navigate the Job Search Show Proficiency of AI Tools such as Descript, Lovable, Relay.ap...
26/01/2026
Alfalite, Brainstorm, Dejero, Domo Broadcast Systems, FOR-A, KitPlus, Ontario So...
26/01/2026
Tyngsboro, Mass. - January 26, 2026 - Broadcast Pix is excited to exhibit at the Alliance for Community Media West Region Conference and Trade Show, taking plac...
26/01/2026
Software for Stable Data Management and Lasting Business Success in Uncertain Ti...
26/01/2026
RT is today publishing a statistical summary of the Register of External Activities for the third quarter of 2025.
The RT Register of External Activities com...
25/01/2026
Back to All News
Sins of Kujo' Premieres April 2: Teaser Trailer, Art and ...
24/01/2026
Masami Kawai Selected as the 2026 Merata Mita Fellow; Isabella Madrigal and Tsanavi Spoonhunter Named 2026 Graton Fellows During Native Forum Celebration in Par...
24/01/2026
The MC-55A Peregrine aircraft will give the Royal Australian Air Force information superiority and serve as strategic assets for future Australian Defence Force...