Summary: For decades, “neuroinflammaging” — the slow, chronic inflammation that contributes to brain fog and memory decline — was considered an unavoidable consequence of aging. A landmark study from Texas A&M now suggests that process may be reversible.
Researchers have developed a non-invasive intranasal therapy that uses microscopic biological parcels to deliver therapeutic microRNAs directly to the brain. With only two doses, the treatment markedly reduced chronic inflammation, restored mitochondrial function, and improved memory and cognitive performance in aged models.
Key Facts
- Rapid, durable effects: Cognitive improvements appeared within weeks and persisted for months after just two intranasal doses.
- Effective across sexes: The therapy produced similar benefits in both male and female models, a notable outcome in biomedical research.
- Behavioral recovery: Treated models regained the ability to recognize familiar objects and respond to new ones, indicating restored hippocampal function.
- Broader potential: Besides addressing age-related decline, the approach could be adapted for recovery after stroke and for slowing neurodegenerative diseases such as Alzheimer’s.
- Patent pending: Texas A&M has filed a U.S. patent, advancing the technique toward clinical development.
Source: Texas A&M
Imagine your brain as a high-performance engine that, over time, not only wears down but also overheats.
Small, persistent inflammations smolder in the hippocampus — the brain’s memory center — producing a chronic brain fog that reduces the ability to form and recall memories, slows thinking, and increases vulnerability to neurodegenerative disorders.
Researchers call this chronic process “neuroinflammaging.” Until now, it was widely regarded as an inevitable aspect of aging.
A study led by Dr. Ashok Shetty at the Texas A&M Naresh K. Vashisht College of Medicine challenges that idea. The team developed a nasal spray containing extracellular vesicles derived from human neural stem cells. These tiny vesicles carry regulatory microRNAs that modulate inflammatory pathways in the brain.
Dr. Shetty, together with senior scientists Dr. Madhu Leelavathi Narayana and Dr. Maheedhar Kodali, report that two intranasal doses significantly lowered markers of brain inflammation, rejuvenated neuronal mitochondria, and produced measurable improvements in memory-related behaviors. Remarkably, the benefits emerged quickly and lasted for months.
These findings, published in the Journal of Extracellular Vesicles, could change the trajectory of therapies for aging-related cognitive decline and reshape how scientists view brain aging itself.
From brain fog to focused cognition: implications for therapy
If this approach translates to humans, a simple two-dose nasal therapy could offer a safe, non-invasive alternative to more complex or risky interventions. The societal implications are large: dementia incidence is expected to rise substantially in coming decades, increasing the urgency for effective prevention and treatment strategies.
The study’s consistent results across both sexes also support broad applicability, reducing a common translational hurdle seen in many biomedical studies.
Researchers envision future applications ranging from slowing cognitive aging to supporting recovery after stroke, with the goal of promoting “successful brain aging” — maintaining mental sharpness, social engagement, and functional independence as people grow older.
How the therapy works: rewiring the brain from within
The therapy centers on extracellular vesicles (EVs), tiny, naturally occurring carriers that deliver microRNAs and other molecular cargo to recipient cells. Packed into a nasal spray, these EVs bypass the blood-brain barrier by traveling along olfactory pathways and directly entering brain tissue.
Once in the hippocampus, EVs are taken up by microglia and other resident cells. The microRNAs within them act as master regulators, suppressing inflammatory signaling pathways such as the NLRP3 inflammasome and the cGAS–STING pathway, both implicated in chronic neuroinflammation.
At the cellular level, the treatment improved mitochondrial function — the neurons’ energy producers — reducing oxidative stress and restoring cellular metabolism. These changes translated into improved information processing and memory consolidation at the behavioral level.
Behavioral assays confirmed the biological effects: treated models performed better at tasks requiring recognition of familiar and novel objects and adapted more readily to changes in their environment, reflecting a rejuvenated hippocampus.
The team also identified specific microRNAs (including miRNA-30e-3p and miRNA-181a-5p) that contribute to inhibiting key inflammatory pathways, strengthening the mechanistic basis for the observed benefits.
With a U.S. patent filed, the research team is preparing for the next steps toward clinical development while continuing to investigate safety, dosing, and long-term outcomes.
Behind the breakthrough
Texas A&M’s multidisciplinary team, supported by the National Institute on Aging, combined expertise in regenerative medicine, molecular neuroscience, and behavioral science to translate basic discoveries into a promising therapeutic approach.
“We are moving beyond understanding mechanisms to creating therapies that could preserve cognitive health,” Dr. Shetty said. The research highlights how coordinated funding, collaboration, and focused translational efforts can accelerate progress against age-related brain disorders.
While more research is necessary before human use, these results demonstrate that age-related neuroinflammation is a modifiable target and suggest new directions for restoring brain function in aging populations.
Key Questions Answered:
A: Most drugs are blocked by the blood-brain barrier. This spray uses extracellular vesicles — tiny, natural particles that the brain accepts. Delivered intranasally, they travel along olfactory pathways to the hippocampus and other brain regions, effectively bypassing the barrier.
A: In the reported models, the treatment improved performance compared with controls. Behavioral tests showed older subjects regained recognition and responsiveness similar to younger models, indicating an actual restoration of function rather than merely halting decline.
A: The therapy is currently at the research and patent stage. Because it is non-invasive and effective across sexes in preclinical models, the team anticipates moving toward clinical trials, but precise timelines will depend on regulatory and trial outcomes.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- The full journal paper was reviewed.
- Additional context was provided by the editorial staff.
About this brain aging research news
Author: Zaid Elayyan
Source: Texas A&M
Contact: Zaid Elayyan – Texas A&M
Image: Credit to Neuroscience News
Original Research: Open access. “Intranasal Human NSC-Derived EVs Therapy Can Restrain Inflammatory Microglial Transcriptome, and NLRP3 and cGAS-STING Signalling, in Aged Hippocampus” by Leelavathi N. Madhu et al., Journal of Extracellular Vesicles. DOI: 10.1002/jev2.70232
Abstract
Intranasal Human NSC-Derived EVs Therapy Can Restrain Inflammatory Microglial Transcriptome, and NLRP3 and cGAS-STING Signalling, in Aged Hippocampus
Neuroinflammaging — a moderate, chronic, sterile inflammation of the hippocampus — contributes to age-related cognitive decline. This process involves activation of the NLRP3 inflammasome and the cGAS–STING pathway, which trigger type I interferon signaling.
Extracellular vesicles derived from human induced pluripotent stem cell–derived neural stem cells (hiPSC-NSC-EVs) carry therapeutic microRNAs known to reduce neuroinflammation. The study tested two intranasal doses of hiPSC-NSC-EVs in late middle-aged mice and analyzed effects in the hippocampus several months later.
Compared with controls, treated animals showed reduced astrocyte hypertrophy, fewer microglial clusters, lower oxidative stress, and higher expression of antioxidant proteins and genes that support mitochondrial respiratory chain integrity. Protein levels associated with NLRP3 activation, p38/MAPK signaling, cGAS–STING–IFN-I signaling, and JAK–STAT pathways were diminished after treatment.
In vitro assays indicated that specific miRNAs present in the EVs—miRNA-30e-3p and miRNA-181a-5p—can inhibit NLRP3 inflammasome and STING pathway activation, respectively. Single-cell RNA sequencing seven days after treatment revealed widespread changes in microglial transcriptomes, including increased expression of genes promoting oxidative phosphorylation and reduced expression of genes driving proinflammatory signaling.
Those molecular and cellular changes correlated with improved cognitive and memory performance. Thus, intranasal hiPSC-NSC-EVs delivered in late middle age can reduce proinflammatory microglial programs and signaling cascades that underlie neuroinflammaging in the hippocampus, supporting better brain function in old age.