Stroke remains one of the leading causes of death, disability, increased economic burden and decreased quality of life around the world. Current stroke therapies are time-limited and largely focused on restoring blood flow, and there are few which address the secondary wave of inflammation that causes further injury in the hours and days after stroke.
A study by researchers from the Yong Loo Lin School of Medicine, National University of Singapore (NUS Medicine), has shown that a class of drugs, HDACi (histone deacetylase inhibitors), protects neurons and limits brain damage following stroke by altering the gene expression of microglia, the immune cells of the brain.
HDACi are currently used or being tested as treatments for certain cancers and are also being researched for neurological conditions such as Alzheimer’s disease.
SignificanceThe highly scattering nature of near-infrared light in human tissue makes it challenging to collect photons using source-detector separations larger than several centimeters. The limits of detectability of light transmitted through the head remain unknown. Detecting photons in the extreme case through an entire adult head explores the limits of photon transport in the brain. AimWe explore the physical limits of photon transport in the head in the extreme case wherein the source and detector are diametrically opposite. ApproachSimulations uncover possible migration pathways of photons from source to detector. We compare simulations with time-resolved photon counting experiments that measure pulsed light transmitted through the head. ResultsWe observe good agreement between the peak delay time and width of the time-correlated histograms in experiments and simulations. Analysis of the photon migration pathways indicates sensitivity to regions of the brain well beyond accepted limits. Source repositioning can isolate sensitivity to targeted regions of the brain, including under the cerebrum. ConclusionsWe overcome attenuation of ∼1018 and detect photons transmitted through an entire adult human head for a subject with fair skin and no hair. Photons measured in this regime explore regions of the brain currently inaccessible with noninvasive optical brain imaging.
Alternative models for studying aging have employed unicellular organisms such as the budding yeast Saccharomyces cerevisiae. Studying replicative aging in yeast has revealed insights into evolutionarily conserved enzymes and pathways regulating aging[ 12-14 ] as well as potential interventions for mitigating its effects.[ 15 ] However, traditional yeast lifespan analysis on agar plates and manual separation cannot track molecular markers and yeast biology differs from humans.[ 16 ]
Animal models, including nematodes, flies, and rodents, play a vital role in aging research due to their shorter lifespans and genetic manipulability, making them useful for mimicking human aging phenotypes.[ 17 ] These models have provided many insights into the fundamental understanding of aging mechanism. However, animal models come with several limitations when applied to human aging and age-related diseases. Key issues include limited generalizability due to species-specific differences in disease manifestation and physiological traits. For example, animal models often exhibit physiological differences, age at different rates, and may not fully replicate human conditions like cardiovascular disease,[ 18 ] immune response,[ 19 ] neurodegenerative diseases,[ 20 ] and drug metabolism.[ 21 ] Furthermore, in vivo models, such as rodents and non-human primates, suffer from limitations such as high costs, low throughput, ethical concerns, and physiological differences compared to humans. The use of shorter lifespan or accelerated aging models, along with the absence of long-term longitudinal data, can further distort the natural aging process and hinder our understanding of aging in humans. Additionally, many animal models rely on inbred strains, which lack genetic diversity and may not fully represent evolutionary complexity.[ 22 ]
In recent years, microfluidics has emerged as a promising tool for studying aging, offering of physiologically relevant 3D environments with high-throughput capabilities that surpass the limitations of traditional 2D cultures and bridge the gap between animal models and human As a multidisciplinary technology, microfluidics processes or manipulates small volumes of fluids (from pico to microliters) within channels measuring 10–1000 µm.[ 23 ] Traditional fabrication methods, such as photolithography and soft lithography, particularly using polydimethylsiloxane (PDMS), remain widely used due to their cost-effectiveness and biocompatibility. However, newer approaches, including 3D printing, injection molding, and laser micromachining, offer greater flexibility for rapid prototyping and the creation of complex architectures. Design considerations are equally critical and are tailored to the specific application, focusing on parameters such as channel geometry, fluid dynamics, material properties, and the integration of on-chip components like valves, sensors, and actuators. A comprehensive overview of the design and fabrication of microphysiological systems is beyond the scope of this review; readers are referred to existing reviews for further detail.[ 24-26 ] Microfluidic devices offer numerous advantages, including reduced resource consumption and costs, shorter culture times, and improved simulation of pathophysiological conditions in 3D cellular systems compared to other model systems (Figure 1).[ 27 ] Therefore, microfluidics platforms have been extensively employed in various domains of life science research, such as developmental biology, disease modeling, drug discovery, and clinical applications,[ 28 ] positioning this technology as a significant avenue in the field of aging research.
For decades, scientists have used near-infrared light to study the brain in a noninvasive way. This optical technique, known as fNIRS (functional near-infrared spectroscopy), measures how light is absorbed by blood in the brain, to infer activity.
Valued for portability and low cost, fNIRS has a major drawback: it can’t see very deep into the brain. Light typically only reaches the outermost layers of the brain, about 4 centimeters deep—enough to study the surface of the brain, but not deeper regions involved in critical functions like memory, emotion, and movement.
This drawback has restricted the ability to study deeper brain regions without expensive and bulky equipment like MRI machines.
Among the tens of thousands of ant species, incredible “intelligent” behaviors like crop culture, animal husbandry, surgery, “piracy,” social distancing, and complex architecture have evolved.
Yet at first sight, the brain of an ant seems hardly capable of such feats: it is about the size of a poppy seed, with only 0.25m to 1m neurons, compared to 86bn for humans.
Now, researchers from Israel and Switzerland have shown how “swarm intelligence” resembling advance planning can nevertheless emerge from the concerted operation of many of these tiny brains. The results are published in Frontiers in Behavioral Neuroscience.
As companies such as Elon Musk’s Neuralink begin human trials of high-risk brain implants, a new proposal calls for a major change in how the U.S. handles injuries caused by the devices.
The article published in Science suggests a “no-fault” compensation program to help patients harmed by devices like brain-computer interfaces (BCIs)—even when no one is legally at fault.
These devices, which are implanted in the brain to treat serious conditions like epilepsy or paralysis, can offer life-changing benefits. But they also come with serious risks such as seizures, strokes or even death. And when something goes wrong, patients often have no way to get help or compensation.
Dr. Eric Topol, a 70-year-old cardiologist, challenges conventional aging perceptions by embracing strength training. Abandoning cardio, he discovered that building muscle mass significantly improves health span. His regimen of simple exercises at home led to increased strength, balance, mental focus, and confidence, proving that aging can be a period of renewal, not decline.