Novel drug delivery particles use neurotransmitters as a 'passport' into the brain

Biomedical engineers at the Tufts University School of Engineering have developed tiny lipid-based nanoparticles that incorporate neurotransmitters to help carry drugs, large molecules, and even gene editing proteins across the blood-brain barrier and into the brain in mice. The innovation, published July 24, 2020, in Science Advances, could overcome many of the current limitations encountered in delivering therapeutics into the central nervous system, and opens up the possibility of using a wide range of therapeutics that would otherwise not have access to the brain. "We can deliver a wide range of molecules by packaging them into the lipid-based nanoparticles without chemically modifying the drugs themselves. We can also achieve delivery across the blood-brain barrier without disrupting the integrity of the barrier," said Qiaobing Xu, associate professor of biomedical engineering at Tufts University and corresponding author of the study. The study authors made use of the fact that certain neurotransmitters have the chemical "passport" required to gain access throughout the brain. By attaching a lipid (fat-like) molecule to the neurotransmitter, the resulting NT-lipidoid can be doped into lipid nanoparticles. The lipid nanoparticles can be injected intravenously, and carry the drugs to the blood-brain barrier. The NT-lipidoid helps the lipid nanoparticles to carry the drugs across the barrier. The lipid nanoparticles can then fuse with neurons and other cells in the brain to deliver their therapeutic payload. Xu said that more studies and clinical trials are needed to determine the efficacy and safety of the delivery method in humans.

SARS-CoV-2 infection of non-neuronal cells, not neurons, may drive loss of smell in patients with COVID-19

An international team of researchers led by neuroscientists at Harvard Medical School (HMS) has identified the olfactory cell types most vulnerable to infection by SARS-CoV-2. Reporting in Science Advances on July 24, 2020, the research team found that olfactory sensory neurons do not express the gene that encodes the ACE2 receptor protein, which SARS-CoV-2 uses to enter human cells. Instead, ACE2 is expressed in cells that provide metabolic and structural support to olfactory sensory neurons, as well as certain populations of stem cells and blood vessel cells. The findings suggest that infection of nonneuronal cell types may be responsible for anosmia in COVID-19 patients and help inform efforts to better understand the progression of the disease. "Our findings indicate that the novel coronavirus changes the sense of smell in patients not by directly infecting neurons but by affecting the function of supporting cells," said senior study author Sandeep Robert Datta, associate professor of neurobiology in the Blavatnik Institute at HMS. This implies that in most cases, SARS-CoV-2 infection is unlikely to permanently damage olfactory neural circuits and lead to persistent anosmia, Datta added, a condition that is associated with a variety of mental and social health issues, particularly depression and anxiety. "I think it's good news, because once the infection clears, olfactory neurons don't appear to need to be replaced or rebuilt from scratch," he said. "But we need more data and a better understanding of the underlying mechanisms to confirm this conclusion."

Pandemic to accelerate adoption of electronic patient portal for epilepsy

The COVID-19 pandemic is a catalyst to accelerate the adoption of technology-enabled patient care for epilepsy, according to a new study published in Epilepsia. Building on the Epilepsy Lighthouse Project, the research was led by Futureneuro, the Science Foundation Ireland’s Research Centre for Chronic and Rare Neurological Diseases. The study describes an electronic patient portal for people with epilepsy that has been developed for patients in Ireland. Named PiSCES (providing individualized services and care for people with epilepsy), the portal is linked to the Irish National Epilepsy Electronic Patient Record. Users of PiSCES can access their clinic visit summaries and tools to report outcomes, such as frequency of seizures. The portal also allows people to track epilepsy care goals and send secure messages directly to their health care provider. "The COVID-19 pandemic has increased the urgency to accelerate much needed health service reform to implement innovations such as electronic patient portals. PiSCES has the capability to transform out-patient care for people with epilepsy, by maximizing health service resources that may be constrained in the aftermath of the pandemic,” said Mary Fitzsimons, eHealth lead at Futureneuro. "In the aftermath of COVID-19, it is highly unlikely that the health care sector will return to a 'business as usual' way of delivering services as we knew them previously. The pandemic has been a catalyst for change in how patient care will be conducted in the future, delivering technology-enables care that is more responsive to individual patient needs and preferences," she said.