A variety of approaches show some promise in improving the function of stem cells in aged tissues. Stem cell populations support their tissue by providing a supply of daughter somatic cells to replace losses. This supply diminishes over time as stem cells reduce their activity for reasons that descend from the known root causes of aging, but which are not fully understood in detail. To the degree that reduced stem cell function is a response to the aged environment rather than a consequence of damage inherent to these cells, then it is useful to find ways to force stem cells to be more active ..read more

In recent years, researchers have been putting more effect into analyses of the CALERIE 2 study of human calorie restriction. The study took place some years ago, but new results continue to be published. Here, researchers show that effects on telomere length and a related aging clock are inconclusive. Telomere length measured in the white blood cells of a blood sample is not a great measure of aging. It is highly variable between individuals, is influenced day to day changes in immune status, and it takes a fairly large study group for age-related trends to show up. It has rightfully been ecl ..read more

Researchers here report on the results of transfusion of young rat plasma into old rats, starting every other week in later life. The study is small, and is one more data point to add to a mixed set of results. Plasma transfusion from young individual to old individual doesn't look that impressive, all told, either in animals or in human patients. That doesn't appear to be discouraging the community of researchers and developers who continue to work on approaches to transfusion that they believe may move the needle. The example here is a straightforward approach to transfusion, the procedure c ..read more

The research community has come to see chronic inflammation and other age-related immune system dysfunctions as an important aspect of neurodegenerative conditions. Inflammation in the short term is necessary for defense against pathogens and regeneration following injury. Unresolved, constant inflammation is harmful to tissue structure and function, however, changing cell behavior for the worse. In brain tissue, the effects of inflammatory signaling on the behavior of innate immune cells called microglia appears particularly important. Neurogenerative conditions are characterized by activated ..read more

Mitrix Bio is one of the companies developing the means to produce large amounts of mitochondria for transplantation. Cells will take up new mitochondria from the surrounding environment, and mitochondria can be harvested from cell cultures. Mitochondrial function declines with age, the result of (a) gene expression changes in the cell nucleus that alter mitochondrial dynamics and the quality control process of mitophagy, and (b) damage to mitochondrial DNA. Evidence from animal studies suggests that replacing mitochondria in aged tissues produces benefits to health and organ function that las ..read more

Researchers here look at cellular dysfunction that may form the earliest stages of Alzheimer's disease, prior to the accumulation of misfolded amyloid-β and cognitive decline. In general, intervening early in the progression of a disease will always be easier, given the right target. The challenge lies in identifying and understanding the causative mechanisms, in an environment in which (a) there is little access to brain tissue in the earliest stages of Alzheimer's disease, and (b) the animal models are highly artificial, as mice do not normally develop anything resembling Alzheimer's disease ..read more

Like the accumulation of senescent cells, loss of stem cell function is a problematic feature of aging. Also like the accumulation of senescent cells, loss of stem cell function is likely downstream of a combination of forms of molecular damage and consequent changes in cell behavior and cell signaling that are presently incompletely understood in detail and harder to address. Senescent cells can be cleared more readily than prevented, and stem cells may be more readily coerced into activity or replaced entirely than is the case for prevention of their age-related functional decline. Stemness ..read more

Researchers here discuss some of the results achieved in building the Human Skeletal Muscle Aging Atlas. Focusing on stem cells in muscle tissue, they find numerous changes in gene expression relating to inflammation and reduced activity. The chronic inflammation characteristic of aging, provoked by senescent cells and innate immune reactions to molecular damage, is known to be involved in many of the dysfunctions of aging. Loss of stem cell activity, and thus a reduced supply of daughter somatic cells to replace losses and repair damage, is one of those dysfunctions. Skeletal muscle aging is ..read more

Fight Aging! publishes news and commentary relevant to the goal of ending all age-related disease, to be achieved by bringing the mechanisms of aging under the control of modern medicine. This weekly newsletter is sent to thousands of interested subscribers. To subscribe or unsubscribe from the newsletter, please visit: https://www.fightaging.org/newsletter/ Longevity Industry Consulting Services Reason, the founder of Fight Aging! and Repair Biotechnologies, offers strategic consulting services to investors, entrepreneurs, and others interested in the longevity industry and its complexities ..read more

The Strategies for Engineered Negligible Senescence (SENS) is a view of aging as accumulated damage. Drawing from the extensive scientific literature on aging, the originators of SENS created an outline of the forms of cell and tissue damage that are fundamental causes of aging, in that they occur as a natural side-effect of the normal operation of our cellular biochemistry. So we might consider the loss of vital cells due to declining stem cell function, mutations to nuclear DNA and mitochondrial DNA, cross-linking of vital molecules in the extracellular matrix, accumulated metabolic waste in ..read more