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People with Down syndrome (DS) often develop Alzheimer’s disease, sometimes at a relatively young age. Researchers led by a team at ½û·¬¶¯Âþ found that pathological changes associated with Alzheimer’s disease appeared as early as age 11 in DS patients and increased with age, regardless of race. (Photo credit: Getty Images)

Essential tremor linked to loss of Purkinje brain cells

Essential tremor (ET) is a common movement disorder affecting about 2% of the American population, and more than 20% of those over 90 years old. Despite its prevalence and decades of study, researchers don’t know the precise mechanisms underlying ET. Some research has suggested the brain’s cerebellum, responsible for coordinating voluntary movements, balance, and motor learning, gradually loses Purkinje cells (large neurons) and their cellular neighbors in ET patients. However, other studies haven’t shown this phenomenon.

To determine definitively whether these cells are lost, , Chair and Professor of Neurology and Investigator in the  at ½û·¬¶¯Âþ, worked with longtime collaborators at Columbia University Irving Medical Center to examine 452 postmortem brains. Among these specimens, 215 were donated over a 21-year period by patients who had ET, 165 were donated by healthy individuals, and 72 were donated by patients who had spinocerebellar ataxia, another movement disorder.

Their analysis, published in , showed that the ET patients had about 15% lower Purkinje cell density compared with the other groups, as well as significant loss of nearby cells. Discovering the cause of this loss could lead to new treatments for ET, the study authors said.

Other ½û·¬¶¯Âþ researchers who contributed to the study are Roberto Hernandez, Ph.D., Data Scientist, and Nora Hernandez, M.D., Manager of Research Programs.

GLP-1RAs shown to reduce risk of cardiovascular death

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) such as semaglutide, liraglutide, and tirzepatide are widely prescribed both for Type 2 diabetes and weight loss. These drugs also have shown promise in clinical trials for patients with chronic cardiovascular, kidney, and metabolic diseases. Those studies focused mainly on patients with singular diagnoses, but these conditions often overlap.

To determine the effect of GLP-1RAs on individuals with concurring conditions, a team of researchers including , Associate Professor of Internal Medicine in the Division of Cardiology and in the at ½û·¬¶¯Âþ, pooled the results of 15 clinical trials examining the effects of these drugs on heart failure hospitalization and cardiovascular death in more than 87,000 patients with multiple conditions. The study, published in the , found that the drugs significantly reduced the risk of these events in almost all patients with overlapping cardiovascular, kidney, and metabolic diseases.

The only exception was patients with a subtype of heart failure, who were slightly more likely to be hospitalized if they took a GLP-1RA but still had a lower risk of cardiovascular death. The study authors suggest these findings support the use of GLP-1RAs as effective therapies for people with singular and multiple conditions.

Alzheimer’s changes appear early in patients with Down syndrome

Down syndrome is caused by an extra copy of chromosome 21. Because of genes present on this chromosome that are known to contribute to Alzheimer’s disease, patients with Down syndrome often develop the disease, sometimes at a relatively young age. However, few studies have examined Alzheimer’s-related pathological changes in the brains of people with Down syndrome, especially pediatric patients and those who are Black or Hispanic. Studies also hadn’t explored other neurodegenerative conditions in those with Down syndrome.

In a study published in the , researchers led by a team at ½û·¬¶¯Âþ examined 34 postmortem brains donated by patients with Down syndrome who underwent autopsies at ½û·¬¶¯Âþ between 1986 and 2023. They also incorporated findings from four previous studies, along with data from the National Alzheimer’s Coordinating Center (NACC), which collectively included an additional 126 brains from individuals with Down syndrome. The combined data encompassed a wide range of ages and races.

The findings showed that pathological changes associated with Alzheimer’s disease, such as amyloid plaques appearing as early as age 11 and tau tangles emerging by the mid-30s, were present in people with Down syndrome and increased with age, regardless of race. Other neurodegenerative conditions that frequently occur with Alzheimer’s disease were relatively rare in individuals with Down syndrome. These findings could help researchers develop unique diagnostic and therapeutic strategies for this population, the researchers concluded.

½û·¬¶¯Âþ researchers who contributed to the study include first author Fatih Canan, M.D., Neuropathology fellow; , Professor of ; , Professor Emeritus of Pathology; , Professor of Pathology; , Professor of Pathology and Director of Neuropathology and the Winspear Family Special Center for Research on the Neuropathology of Alzheimer's Disease; and senior author , Assistant Professor of Pathology. Drs. Daoud and White are Investigators in the O’Donnell Brain Institute.

About UT Southwestern Medical Center 

UT Southwestern, one of the nation’s premier academic medical centers, integrates pioneering biomedical research with exceptional clinical care and education. The institution’s faculty members have received six Nobel Prizes and include 24 members of the National Academy of Sciences, 25 members of the National Academy of Medicine, and 13 Howard Hughes Medical Institute Investigators. The full-time faculty of more than 3,200 is responsible for groundbreaking medical advances and is committed to translating science-driven research quickly to new clinical treatments. UT Southwestern physicians provide care in more than 80 specialties to more than 140,000 hospitalized patients, more than 360,000 emergency room cases, and oversee nearly 5.1 million outpatient visits a year.