neurology

Alzheimer's disease, the most common form of dementia, is linked to the presence of tau protein deposits and amyloid plaques in the brain. Now, a team at Johns Hopkins University (USA) has identified more than 200 misfolded proteins in rat brains that are associated with age-related cognitive decline. Although the study does not allow us to know whether they play a causal role, the authors claim that amyloid plaques ‘are just the tip of the iceberg.’ The results are published in the journal Science Advances.

Prenatal exposure to triptans—alone or in combination with other migraine medications—does not increase the risk of developmental disorders in children up to age 14, according to research published in Neurology. The study is based on data from more than 26,000 pregnancies in a national registry in Norway and includes autism spectrum disorders, language disorders, and attention deficit hyperactivity disorder, among other diagnoses.

A migraine treatment drug, ubrogepant, also reduces common non-headache symptoms that occur in the hours before a migraine, according to the results of a large phase III clinical trial published in Nature Medicine. The results suggest that this could be the first acute treatment for symptoms that occur before migraine and have a significant impact on daily life, such as dizziness, sensitivity to light and noise, and neck pain.

A phase III clinical trial involving nearly 34,000 people shows that lowering high blood pressure reduces the risk of dementia and cognitive decline. Participants were aged 40 or older, lived in rural areas of China, and had untreated hypertension. The study results are published in Nature Medicine.

Two independent clinical trials demonstrate the safety of stem cell therapies for Parkinson's disease. The papers, published in Nature, investigate the use of cells derived from human induced pluripotent stem cells and human embryonic stem cells, respectively. Parkinson's disease is characterised by the progressive loss of dopamine-producing neurons. Cell therapy, which replenishes dopamine-producing neurons in the brain, could provide a treatment with fewer adverse effects than current treatments. However, further research is needed to test the efficacy and benefits of these new therapies.

A review of 202 studies involving more than 56 million mother-child pairs has observed an association between maternal diabetes — including pre-pregnancy and gestational diabetes — and an increased risk of neurodevelopmental disorders in children, such as autism spectrum disorders, attention deficit hyperactivity disorder or intellectual disability. The authors, who publish the results in the journal The Lancet Diabetes & Endocrinology, call for a cautious interpretation of the association, as there is currently little evidence of a causal relationship.

In marathon runners, the myelin content of specific regions of the brain is reversibly reduced, according to a study carried out in the Basque Country. This observation is consistent with animal evidence suggesting that myelin lipids - a substance that surrounds neurons - can act as energy reserves in extreme metabolic conditions, as detailed by the authors in Nature Metabolism. The analysis is based on magnetic resonance imaging of eight men and two women before and after running a marathon. According to the study, the myelin content was fully recovered two months after the race.

An article reviews evidence on the accumulation of microplastics in human brain tissue recently published in Nature Medicine. The authors highlight practical measures to reduce exposure, noting that switching from bottled water to filtered tap water could reduce microplastic intake from 90,000 to 4,000 particles per year. The paper is a commentary in Brain Medicine. 

Results from a cohort study of more than 100,000 people reveal the strong and persistent association of headache diagnoses with attempted and completed suicide. The authors suggest that behavioural health assessment and treatment may be important for these patients. The paper is published today in the journal JAMA Neurology. 

A study in mice reveals that immune cells in the brain 'engulf' microplastics, forming clumps that can cause brain clots. The findings, published in the journal Science Advances, highlight how microplastics can indirectly damage the brain by disrupting blood flow, rather than directly infiltrating brain tissue cells.