The thymus, a small and relatively unknown organ, may play a bigger role in the immune system of adults than was previously believed. With age, the glandular tissue in the thymus is replaced by fat, but, according to a new study from Linköping University, the rate at which this happens is linked to sex, age and lifestyle factors. These findings also indicate that the appearance of the thymus reflects the aging of the immune system.
“We doctors can assess the appearance of the thymus from largely all chest CT scans, but we tend to not see this as very important. But now it turns out that the appearance of the thymus can actually provide a lot of valuable information that we could benefit from and learn more about,” says Mårten Sandstedt, MD, Ph.D., at the Department of Radiology in Linköping and Department of Health, Medicine and Caring Sciences, Faculty of Medicine and Health Sciences, Linköping University.
The thymus is a gland located in the upper part of the chest. It has been long known that this small organ is important for immune defense development in children. After puberty, the thymus decreases in size and is eventually replaced by fat, in a process known as fatty degeneration. This has been taken to mean that it loses its function, which is why the thymus has for a long time been considered as being not important in adult life.
Caps on the ends of chromosomes are critical for maintaining genetic integrity and promoting healthy aging.
A new study is finding that greener neighborhoods protect telomeres which prevent aging on a genetic level.
The role of telomeres in aging
Telomeres are repetitive sequences of DNA found at the ends of chromosomes that play a crucial role in preserving the integrity and stability of the genetic material within a cell.
As cells divide and their telomeres become progressively shorter, they eventually reach a critical point where they can no longer divide. This state is known as cellular senescence, and it is associated with aging and age-related diseases.
Research led by Peking University, China, has discovered a single type of retinal photoreceptor cell in Drosophila (fruit fly) is involved in both visual perception and circadian photoentrainment by co-releasing histamine and acetylcholine at the first visual synapse.
In a paper, “A single photoreceptor splits perception and entrainment by cotransmission,” published in Nature, the team details the discovery that the Drosophila visual system segregates visual perception and circadian photoentrainment by co-transmitting two neurotransmitters, histamine and acetylcholine, in the R8 photoreceptor cells.
Light detection involves capturing signals through photoreceptors in the eye, which are essential for image formation and subconscious visual functions, such as regulating biological rhythms according to the daily light-dark cycle (photoentrainment of the circadian clock). The optical system has distinct pathways for image formation (based on local contrast) and non-image-related tasks (based on global irradiance).
The naked mole rat won’t win any beauty contests, but it could possibly win in the talent category. Its superpower: fighting the aging process to live several times longer than other animals its size, in a state of youthful vigor.
It’s believed that naked mole rats experience all the normal processes of wear and tear over their lifespan, but that they’re exceptionally good at repairing the damage from oxygen free radicals and the DNA errors that accumulate over time. Even though they possess genes that make them vulnerable to cancer, they rarely develop the disease, or any other age-related disease, for that matter. Naked mole rats are known to live for over 40 years without any signs of aging, whereas mice live on average about two years and are highly prone to cancer.
Now, these remarkable animals may be able to share their superpower with other species. In August, a study provided what may be the first proof-of-principle that genetic material transferred from one species can increase both longevity and healthspan in a recipient animal.
Regenerative medicine and tissue engineering strategies have made remarkable progress in remodeling, replacing, and regenerating damaged cardiovascular tissues. The design of three-dimensional (3D) scaffolds with appropriate biochemical and mechanical characteristics is critical for engineering tissue-engineered replacements. The extracellular matrix (ECM) is a dynamic scaffolding structure characterized by tissue-specific biochemical, biophysical, and mechanical properties that modulates cellular behavior and activates highly regulated signaling pathways. In light of technological advancements, biomaterial-based scaffolds have been developed that better mimic physiological ECM properties, provide signaling cues that modulate cellular behavior, and form functional tissues and organs.
Read about NIH-funded research that shows reducing calories may improve health benefits.