Sci Adv: A new nanoparticle delivery platform that breaks through the blood-brain barrier and brings hope to a wide range of neurological diseases

The blood-brain barrier (BBB) refers to the barrier between plasma formed by capillaries and glial cells and between plasma and brain cells formed by the veins, allowing only certain types of molecules to flow from the bloodstream into neurons in the brain and other surrounding cells.
The presence of the blood-brain barrier is important to prevent harmful substances from entering the brain from the blood, however, the blood-brain barrier also prevents the transfer of most small molecule drugs and large molecules (such as peptides, proteins and gene-based drugs), severely limiting the treatment of neurologic system diseases such as neurodegenerative diseases, brain tumors, brain infections and strokes.
recently, Harvard Medical School, the Massachusetts Institute of Technology and other organizations in the journal Science Advanceds published a research paper entitled: BBB pathophysiosiology -independent delivery of siRNA in the research brain injury.
research team developed a nanoparticle delivery platform that breaks through the blood-brain barrier and successfully delivers therapeutic drugs to the brain, which in mouse models of traumatic brain injury (TBI) is three times more efficient than previous conventional delivery methods and has significant therapeutic effects, opening up new possibilities for treating a variety of neurological diseases.
Traumatic brain injury (TBI)-related secondary damage, which can lead to Alzheimer's disease, Parkinson's disease, and other neurodegenerative diseases, has previously been developed to deliver therapeutic drugs to the brain after traumatic brain injury (TBI), relying on a short window of temporary damage to the post-traumatic blood-brain barrier, which lacks effective drug delivery tools after the blood-brain barrier is repaired.
the presence of the blood-brain barrier, it is very difficult to break through the blood-brain barrier to deliver large or small molecule therapeutic drugs.
, successful delivery of drugs has always been the holy grail of the field, when the blood-brain barrier is normal.
To overcome this challenge, the team plans to package the drug into biocompasitive nanoparticles with precisely designed surface properties that can be delivered efficiently to the brain without being affected by the state of the blood-brain barrier.
Polylactic acid-hydroxyacetic acid copolymer (PLGA), PLGA is a biodegradable biosysorbable polymer with good bio-compatible, non-toxic, good sac and film-forming properties, is widely used in pharmaceutical, medical engineering materials and modern industrial fields, and has been approved by the U.S. Food and Drug Administration (FDA) as a pharmaceutical supplement.
the team chose PLGA as the base material for nanoparticles.
researchers systematically designed and studied the surface properties of nanoparticles to maximize their penetration of intact blood-brain barriers in healthy mice.
the treatment used in this study is designed to inhibit the expression of tau proteins in small molecules interfering with RNA (siRNA), after many previous studies have shown that tau proteins play a key role in neurodegenerative lesions.
to verify the effect, the team used the new nanoparticle delivery system to deliver anti-tau protein siRNA to a mouse model of traumatic brain injury (TBI).
After traumatic brain injury (TBI), the window period during which the blood-brain barrier was broken, or after the recovery of the blood-brain barrier two weeks later, the nanoparticle system delivered tau protein siRNA, which led to a 50 percent reduction in tau protein expression in the mouse brain, suggesting that the nanoparticle delivery system was able to efficiently break through the normal blood-brain barrier and deliver therapeutic drugs to the brain.
as a controlled routine delivery method, there was no significant change in tau protein in the brains of mice.
the new technology was explored and developed using a traumatic brain injury (TBI) model, basically neurological disorders could benefit from the work, the team said.
this nanoparticle delivery platform is not limited to delivering tau protein inhibitors, but can also be used to deliver a variety of drugs, including antibiotics, anti-tumor drugs, neuropeptides, and so on, which may change the game of central nervous system diseases.
team also said the results provided a huge boost toward multiple therapeutic goals and human trials.