June 4, 2023

Dr Ashley Webb presents interventions that can improve our stem cell function plus a potential way to restore it in this short clip.

Foreign so another intervention that has been um perhaps much more widely studied and easier to implement um is uh is dietary interventions that have been shown to improve healthy aging of stem cells so for example caloric restriction which is a well-conserved sort of rejuvenating intervention has been shown to also enhance stem cell function with age and so

That’s been shown for example in the muscle where calorie restriction or reducing the diet and overall caloric intake and mice has been shown to increase satellite cell number and enhanced muscle stem cell function so um so as a consequence in these animals that have been restricted there’s a an increase in muscle regeneration and transplant efficiency and so

The benefits of caloric restriction are not restricted to just the muscle compartment it’s also been shown that caloric restriction can improve on the the functionality of chromatopoietic stem cells intestinal stem cells and can also result in an increase in neurogenesis and cognitive function now caloric restriction is just one dietary intervention that’s been

Studied in this manner it’s also been found that time restrictive feeding or intermittent fasting can improve stem cell function in animals ketogenic diets have also been shown to improve stem cell functionality and as i mentioned earlier enhancement of certain metabolic cofactors such as nad through treatment with nicotininide riboside have also been shown

To to improve stem cell function and maintenance and then lastly rapamycin has been shown to enhance stem cell functionality and so um it’s important to note that most of these dietary interventions have really only been tested in um in in mice and so it’s unclear yet exactly how humans will benefit and whether stem cell compartments in humans um will actually

Um be improved by um by these interventions but interestingly these interventions have pretty much been shown in every case to function through the the mechanisms that i mentioned earlier um so dietary interventions in general down regulate growth factor signals such as insulin igf signaling and tor activity so they um so what i mean by this is that they’re

Impacting these nutrient sensing pathways that i mentioned earlier um it’s also been shown that these dietary interventions um result in an overall metabolic reprogramming that’s helping for the cell as well as improved immune function to decrease inflammation with age and interestingly in recent work it’s been shown that these dietary interventions can also

Help with the microbiome um status so basically it can for a microbiome remodeling during the aging process that is healthy for aging this has been a huge area of interest recently in the the stem cell field and one area of interest in particular is in using ips based approaches to rejuvenate stem cell pools so in these pluripotent stem cells or ips cells are

Cells that are generated from adult somatic cells or um or embryonic somatic cells um such as fibroblasts and so these somatic cells can effectively be reprogrammed through delivery of a number of transcription factors and this was first shown by yamanaka and so um so delivery of these transcription factors causes an overall reprogramming of these somatic stem

Cells into an embryonic state known as an induced pluripotent stem cell state so these cells are very similar to embryonic stem cells and so that means that they actually have the capacity to differentiate into all lineages and all cell types in the organism and what’s exciting about this process is that um that converting the somatic stem cell to an ips cell

Results in an overall epigenetic and metabolic reprogramming of the cells to a more youthful embryonic state and it also includes features of our regeneration or rejuvenation such as telomere restoration and so there’s been a lot of interest in using the power of these rejuvenating factors or reprogramming factors to um to improve healthy aging so for example

In in the mouse during aging there’s an accumulation of the aging hallmarks that i mentioned earlier that are well known to occur during um during the aging process and delivery of certain levels of these reprogramming factors has been shown to actually epigenetically reprogram old cells into younger cells and this actually works at least to some extent across

Different tissues and cell types including stem cells such as metaboetic stem cells okay so um so in summary i’ve gone over the intrinsic mechanisms of stem cell aging and how they’re impacted by a number of extrinsic mechanisms with age um but i think the really exciting take-home message here is that based on what we know from various interventions there is

Actually potential for rejuvenation of stem cell pools to enhance healthy aging and improve and increase the number of of years that are spent on disease-free in humans foreign

Transcribed from video