Dementia is increasingly recognized as a life-course illness where a variety of lifestyle choices interact with genetic, vascular and other risk factors to affect risk of disease. Given the rapid aging of developed and developing societies, it is projected that the prevalence of dementia will dramatically increase during the next five decades. Therefore, it is a public health priority to explore pathophysiological pathways underlying the development of dementia and its most common cause, AD.
According to the BUSM researchers, a growing body of evidence suggests that leptin has beneficial effects on brain development and function. It appears to mediate structure and functional changes in the hippocampus and to improve memory function. Leptin also has been shown to increase apolipoprotein E-dependent B amyloid uptake into the cell and reduce brain extracellular concentrations of B-amyloid, the major component of the neuritic plaques that are a histopathological hallmark of AD.
Using participants from the original cohort of the Framingham Heart Study, the researchers measured leptin concentrations in 785 persons without dementia. A subsample of 198 dementia-free survivors underwent volumetric brain MRI between 1999 and 2005, approximately 7.7 years after leptin levels were measured. Two measures of brain aging, total cerebral brain volume and temporal horn volume (which is inversely related to hippocampal volume) were assessed. The researchers found that elevated leptin levels was associated with higher total cerebral brain volume and lower temporal horn volume and higher leptin levels were prospectively associated with a lower incidence of AD and dementia.
"Over a 12-year follow-up, this corresponds to an absolute AD risk of 25 percent for persons with the lowest levels of leptin compared to a six percent risk for persons with the highest levels," said senior author Sudha Seshadri, MD, an associate professor of neurology at BUSM and an investigator at The Framingham Heart Study.
"If our findings are confirmed by others, leptin levels in older adults may serve as one of several possible biomarkers for healthy brain aging and, more importantly, may open new pathways for possible preventive and therapeutic intervention," she added.
The BUSM researchers believe further exploration of the molecular and cellular basis for the observed association may expand their understanding of the pathophysiology underlying brain aging and the development of AD.
Funding for this study was provided by the National Heart, Lung and Blood Institute, the National Institute on Aging and the National Institute of Neurological Disorders and Stroke.
Dr. Seshadri and the Neurology study group would like to thank the Framingham Heart Study participants and staff whose extraordinary commitment and dedication makes such scientific insights possible.
Gina M. DiGravio | EurekAlert!
New malaria analysis method reveals disease severity in minutes
14.08.2017 | University of British Columbia
New type of blood cells work as indicators of autoimmunity
14.08.2017 | Instituto de Medicina Molecular
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences