Dopamine neurons in a part of the brain called the midbrain may, with aging, be increasingly susceptible to a vicious spiral of decline driven by fuel shortages, according to a study led by Weill Cornell Medicine investigators. The findings offer a potential explanation for the degeneration of this neuron population in Parkinson’s disease.
In the study, published Dec. 5 in the Proceedings of the National Academy of Sciences, the scientists examined how midbrain dopamine neurons, which have unusually numerous output branches, handle their high energy requirements. They showed that these neurons under normal conditions create a fuel reserve in the form of clusters of glucose molecules called glycogen. This allows the neurons to keep working for a surprisingly long time even when their usual supply of glucose from the blood is interrupted. However, the researchers also discovered that the neurons regulate their glycogen storage in a way that can leave them highly vulnerable to glucose shortages, especially as their functions begin to decline with aging.
“This vulnerability may explain the deaths of these midbrain neurons in Parkinson’s and is consistent with the idea that energy insufficiency is a common failure mode in neurological disorders,” said study senior author Timothy Ryan, the Tri-Institutional Professor of Biochemistry and Biophysics and a professor of biochemistry in anesthesiology at Weill Cornell Medicine.
A single-dose gene replacement therapy is found to improve movement ability in children over 2 years of age and teenagers with spinal muscular atrophy, according to research published in Nature Medicine. The results of this phase 3 clinical trial, involving 126 children and adolescents, could support an alternative to lifelong, repeat-dose treatments for people living with spinal atrophy beyond the age of 2 years.
Spinal muscular atrophy is a rare genetic condition that causes muscle weakness and loss of movement over time. It develops because the body cannot make enough of a protein, called survival motor neuron, needed for healthy nerve cells.
Onasemnogene abeparvovec is a gene therapy that restores production of this missing protein in a single treatment. However, it is currently approved in the U.S. and Europe only as a single intravenous treatment for children under 2 years of age. Therefore, those older than 2 years of age can receive treatments only to slow the disease, and these must be taken regularly, either by injection or orally.
Mental health is a global crisis, with more than 1 billion people affected by mental health conditions, according to the World Health Organization (WHO). Young people are particularly affected, with suicide as the third leading cause of death among those aged 15 to 29. A new study of the mental health of Nepali adolescents published in the journal PLOS One found that more than 40% of teens suffer from anxiety and that parenting style is a major factor influencing mental well-being.
A research team led by Rabina Khadka, a public health lecturer at the Manmohan Memorial Institute of Health Sciences in Kathmandu, surveyed 583 school-going adolescents in Bheemdatt Municipality, Nepal. The aim was to fill in gaps in the existing data, specifically the lack of research on how different parenting styles (authoritative, authoritarian and permissive) relate to a range of mental health outcomes.
Participants were asked to fill out a four-part survey with questions covering their mental health status (levels of depression, anxiety, stress and self-esteem), perceived parenting style and personal information such as age, gender and family situation. The researchers then measured these factors using recognized psychological scales and analyzed the data to find statistical links between the type of parenting teens received and their mental health.
Semaglutide medications like Ozempic and Wegovy can help lower the risk of heart and metabolic diseases in people with schizophrenia spectrum disorders, according to a study published in JAMA Psychiatry.
Glucagon-like peptide–1 receptor agonist (GLP-1RAs) drugs, such as semaglutide, mimic the natural gut hormone GLP-1 that regulates hunger and food intake. By activating GLP-1 receptors in the brain, the drug reduces hunger and slows gastric emptying, helping one feel full longer. It also enhances glucose-dependent insulin secretion, thereby improving blood sugar control.
Researchers in Denmark recruited 73 adults taking antipsychotic medications who were showing early signs of diabetes and had an average BMI of 36, which falls in the category of obesity. The participants, aged 18 to 65 years, were randomly assigned to receive either weekly semaglutide injections or a placebo for 6.5 months.
When it comes to brain function, neurons get a lot of the glory. But healthy brains depend on the cooperation of many kinds of cells. The most abundant of the brain’s non-neuronal cells are astrocytes, star-shaped cells with a lot of responsibilities. Astrocytes help shape neural circuits, participate in information processing, and provide nutrient and metabolic support to neurons. Individual cells can take on new roles throughout their lifetimes, and at any given time, the astrocytes in one part of the brain will look and behave differently than the astrocytes somewhere else.
After an extensive analysis by researchers at MIT, neuroscientists now have an atlas detailing astrocytes’ dynamic diversity. Its maps depict the regional specialization of astrocytes across the brains of both mice and marmosets—two powerful models for neuroscience research—and show how their populations shift as brains develop, mature, and age.
The open-access study, reported in the Nov. 20 issue of the journal Neuron, was led by Guoping Feng, the James W. (1963) and Patricia T. Poitras Professor of Brain and Cognitive Sciences at MIT.
Integrated circuits are the brains behind modern electronic devices like computers or smart phones. Traditionally, these circuits—also known as chips—rely on electricity to process data. In recent years, scientists have turned their attention to photonic chips, which perform similar tasks using light instead of electricity to improve speed and energy efficiency.
An international collaboration led by Cornell researchers used a combination of psilocybin and the rabies virus to map how – and where – the psychedelic compound rewires the connections in the brain.
Specifically, they showed psilocybin weakens the cortico-cortical feedback loops that can lock people into negative thinking. Psilocybin also strengthens pathways to subcortical regions that turn sensory perceptions into action, essentially enhancing sensory-motor responses.
The findings published Dec. 5 in Cell. The lead author is postdoctoral researcher Quan Jiang.