Best and Worst of Neuroscience and Neurology – September 2015by Viatcheslav Wlassoff, PhD | October 6, 2015
As usual, lots of interesting findings in neuroscience and neurology were revealed in September. The choice of articles for this review represents mostly my personal opinion on their importance and interest to general public.
The studies in the “worst” section should not be seen as bad: rather, they challenge the existing views and allow to look at the facts from a different angle.
On the 9th September, the scientific community marks the birthday of Daniel Carleton Gajdusek, the recipient of the 1976 Nobel Prize in Physiology and Medicine. Although Gajdusek’s legacy remains controversial, his works on the disease kuru that existed among cannibalistic tribes of New Guinea laid a foundation stone for the discovery of prions and the modern understanding of many neurodegenerative conditions. The story of this discovery perfectly illustrates that fundamental discoveries may come from totally unexpected corners.
Coincidentally, one of the papers published this month describes yet another potentially infectious prion disease. Such diseases are rare: this is the first discovery of infectious human prions in the last 50 years!
New type of prion in multiple system atrophy
The role of prions in the development and progression of neurodegenerative conditions is now well established. There is, however, only a handful of human diseases where prions act as infectious agents. This makes the new discovery of a prion potentially involved in the transmission of multiple system athrophy (MSA) particularly important.
MSA is a rare condition with symptoms similar to Parkinson’s disease. The misfolded version of a protein called alpha-synuclein precipitates inside brain cells, forming inclusions and eventually causing the disease to progress. New experiments show that this prion can potentially be transmitted during medical and surgical procedures. Although the findings are not confirmed on humans, researchers call for preventive measures while dealing with the tissues from MSA patients.
Initial steps of tauopathies revealed
Many neurodegenerative disorders, such as Alzheimer’s disease, are characterized by accumulation of insoluble tangles of tau-proteins in the brain cells. However, it was always unclear what exactly triggers this process. New data published this month bring us one step closer to solving this problem. It was demonstrated that a protein called appoptosin plays a key role at the early stages of tauopathies. Increased level of appoptosin leads to the cleavage of tau protein leading to the formation of tau version keen on agglomerating. New findings provide an important potential new target for early pharmaceutical intervention into the development of neurodegenerations.
New technique for early diagnosis of Alzheimer’s disease
Routine diagnostics of Alzheimer’s disease involves various cognitive tests and brain tomography. Unfortunately, this is usually done when the symptoms of disease are already obvious. Although no treatment is currently available for this condition, the early detection is important for its successful management. The only tool of early diagnostics currently available is the analysis of cerebrospinal fluids. This, however, involves rather invasive procedure and therefore hardly ever done.
Newly developed amyloid PET scans might help to address this problem. The technique involves the administration of a compound known to bind to beta-amyloid, followed by PET scan aimed at detecting this compound. The method was shown to have diagnostic sensitivity as the analysis of cerebrospinal fluid samples.
Resveratrol might be able to stop the progression of Alzheimer’s disease
Natural anti-oxidant resveratrol is highly praised for multiple positive effects on the body, ranging from improvements in cardiovascular system to possible slowing down of aging.
A new trial on Alzheimer’s patients receiving high doses of purified resveratrol demonstrated that the compound stabilizes the level of amyloid-beta 40 in the patients. Amyloid-beta 40 is a biomarker linked to the progression of Alzheimer’s disease. Its level in the blood and cerebrospinal fluid gradually decreases with the disease progression. The results suggest that resveratrol may be able to at least stop the deterioration of patients’ conditions and cognitive abilities caused by this neurodegenerative disorder.
New study reveals neural mechanism responsible for fat breakdown
Stimulation of the neurons involved can lead to the fat breakdown via release of neuromediator norepinephrine, which initiates signaling pathways leading to the hydrolysis of fat. The discovery points to a new mechanism involved in the regulation of body mass and thus is likely pave the way to new anti-obesity treatments.
Modeling of brain is too complex for modern computers
With its 100 billion constituting cells, the human brain is rather difficult to study. Scientists traditionally use a modeling approach to simplify the complex system. Although such models retain only the most important features of the real system, they often help to reveal the fundamental principles behind the behavior of much more complex real things. It appears, however, that there is a serious stumbling block on the way to the computer modeling of brain.
Scientists demonstrated that the intensity of interaction between the neural cells cannot be correctly reflected by the models if the number of cells in the model is below certain level. Unfortunately, even modern supercomputers are not powerful enough to reach this level. This simply means that whatever results the current computer modeling approaches might bring, their validity will remain questionable.
Efficiency of exercise in Parkinson’s patients questioned
People suffering from Parkinson’s disease commonly experience various motor symptoms such as problems with balance, gait and the risk of falls. This often stops them from being physically active which, in turn, may lead to the worsening of symptoms. Exercise programs aimed at supporting the balance are usually advised to the patients, but their effectiveness was questioned in a study published this month.
Researchers compared the severity of motor symptoms in patients who perform exercises with the patients who are active on the daily basis performing various tasks at home and outdoors. It turned out that the symptoms were less severe in the non-exercise group. Apparently, simply moving around works better than any specifically designed exercise interventions.
No link between breastfeeding and child’s intelligence
A number of recent reports provided rather convincing evidences that prolonged breastfeeding can lead to higher IQ of the child. This would not be totally surprising, as human milk is rich on polyunsaturated fatty acids which are important for the development of brain.
However, the results of further tests published this month decisively contradict the earlier findings. Using the data from almost 12,000 twins who were breastfed at different periods of time in infancy, researchers found no link between the breastfeeding and cognitive abilities. Twin method is known to produce very reliable results, and the new findings put the question mark on the conclusions of previous studies.
Early-age football linked to increased risk of brain injury
There is a mounting number of publications raising the concerns about the long-term effects of playing American football. It was recently reported that overwhelming majority of deceased former football players had neurodegenerative brain conditions. These concerns were further raised by the findings published this month.
It was demonstrated that those players who started early, before the age of 12, are at much higher risk of developing brain problems later in life. Memory, reasoning and planning abilities were more affected in those early starters even if the number of concussions they suffered was not higher than in the late starters.
Link between TBI and energy drinks consumption
Another article published this month brings further concerns about the association between traumatic brain injury (TBI), playing sports and consumption of energy drinks and alcohol among teenagers.
Researchers found that the risk of sustaining TBI is several times higher among teens consuming large amount of energy drinks, particularly when these drinks were mixed with alcohol. The risk was particularly high among youngsters playing sports. Obviously, the drinks themselves cannot be seen as causative factor in TBI. However, caffeinated energy drinks enhance mood and physical and mental states that, in turn, may lead to increased risk taking while playing. Clearly, this is something for parents and coaches to take into account.
van Albada, S., Helias, M., & Diesmann, M. (2015). Scalability of Asynchronous Networks Is Limited by One-to-One Mapping between Effective Connectivity and Correlations PLOS Computational Biology, 11 (9) DOI: 10.1371/journal.pcbi.1004490
Ilie, G., Boak, A., Mann, R., Adlaf, E., Hamilton, H., Asbridge, M., Rehm, J., & Cusimano, M. (2015). Energy Drinks, Alcohol, Sports and Traumatic Brain Injuries among Adolescents PLOS ONE, 10 (9) DOI: 10.1371/journal.pone.0135860
Palmqvist, S., Zetterberg, H., Mattsson, N., Johansson, P., , ., Minthon, L., Blennow, K., Olsson, M., , ., & Hansson, O. (2015). Detailed comparison of amyloid PET and CSF biomarkers for identifying early Alzheimer disease Neurology, 85 (14), 1240-1249 DOI: 10.1212/WNL.0000000000001991
Prusiner, S., Woerman, A., Mordes, D., Watts, J., Rampersaud, R., Berry, D., Patel, S., Oehler, A., Lowe, J., Kravitz, S., Geschwind, D., Glidden, D., Halliday, G., Middleton, L., Gentleman, S., Grinberg, L., & Giles, K. (2015). Evidence for ?-synuclein prions causing multiple system atrophy in humans with parkinsonism Proceedings of the National Academy of Sciences, 112 (38) DOI: 10.1073/pnas.1514475112
Snider, J., Müller, M., Kotagal, V., Koeppe, R., Scott, P., Frey, K., Albin, R., & Bohnen, N. (2015). Non-exercise physical activity attenuates motor symptoms in Parkinson disease independent from nigrostriatal degeneration Parkinsonism & Related Disorders, 21 (10), 1227-1231 DOI: 10.1016/j.parkreldis.2015.08.027
Stamm, J., Koerte, I., Muehlmann, M., Pasternak, O., Bourlas, A., Baugh, C., Giwerc, M., Zhu, A., Coleman, M., Bouix, S., Fritts, N., Martin, B., Chaisson, C., McClean, M., Lin, A., Cantu, R., Tripodis, Y., Stern, R., & Shenton, M. (2015). Age at First Exposure to Football Is Associated with Altered Corpus Callosum White Matter Microstructure in Former Professional Football Players Journal of Neurotrauma DOI: 10.1089/neu.2014.3822
Turner, R., Thomas, R., Craft, S., van Dyck, C., Mintzer, J., Reynolds, B., Brewer, J., Rissman, R., Raman, R., Aisen, P., & , . (2015). A randomized, double-blind, placebo-controlled trial of resveratrol for Alzheimer disease Neurology DOI: 10.1212/WNL.0000000000002035
von Stumm, S., & Plomin, R. (2015). Breastfeeding and IQ Growth from Toddlerhood through Adolescence PLOS ONE, 10 (9) DOI: 10.1371/journal.pone.0138676
Zeng, W., Pirzgalska, R., Pereira, M., Kubasova, N., Barateiro, A., Seixas, E., Lu, Y., Kozlova, A., Voss, H., Martins, G., Friedman, J., & Domingos, A. (2015). Sympathetic Neuro-adipose Connections Mediate Leptin-Driven Lipolysis Cell, 163 (1), 84-94 DOI: 10.1016/j.cell.2015.08.055
Zhao, Y., Tseng, I., Heyser, C., Rockenstein, E., Mante, M., Adame, A., Zheng, Q., Huang, T., Wang, X., Arslan, P., Chakrabarty, P., Wu, C., Bu, G., Mobley, W., Zhang, Y., St. George-Hyslop, P., Masliah, E., Fraser, P., & Xu, H. (2015). Appoptosin-Mediated Caspase Cleavage of Tau Contributes to Progressive Supranuclear Palsy Pathogenesis Neuron, 87 (5), 963-975 DOI: 10.1016/j.neuron.2015.08.020
No future articles scheduled.
This Sunday February 14th (9 p.m. ET), the Emmy-nominated Brain Games tv-show is back! Wonder junkie Jason Silva returns to our screens, teaming up with... READ MORE →
Like what you read? Give to Brain Blogger sponsored by GNIF with a tax-deductible donation.Make A Donation