Search results for "Stem cell theory of aging"
showing 5 items of 5 documents
Collecting evidence for a stem cell hypothesis in HCC.
2010
Ever since Ernest McCulloch and James E Till defined essential stem cell properties, the field of stem cell biology has attracted increasing interest.1 Manipulating embryonic stem cells has resulted in advanced genetic technologies such as knock-out and transgenic animals, providing valuable models to study genetic influence on a wide variety of diseases.2 The success in manipulating stem cells and the ability to differentiate them into diverse tissues brought with them countless concepts of utilising stem cells in medicine. The idea of perpetually dividing pluripotent cells, capable of differentiating into nearly every possible cell or tissue type, seems like an inexhaustible resource for …
Wharton’s Jelly Mesenchymal Stem Cells for the Treatment of Type 1 Diabetes
2014
Type 1 diabetes is an autoimmune disease caused by the destruction of endocrine pancreas β cells by T lymphocytes, for which genetic and environmental risk factors have been proposed. Patients require daily infusions of recombinant insulin to overcome the reduced production by their own cells, but there is an increasing demand for a permanent and efficient supplementation which could better modulate the need for the hormone during the normal activities. For this reason, transplant-based therapeutic models have been proposed such as whole organ transplantation and Langerhans islets transplantation. These techniques are limited by many factors such as the lack of donors, the risks linked to t…
Subtle Changes in Clonal Dynamics Underlie the Age-Related Decline in Neurogenesis
2017
SUMMARYNeural stem cells in the adult murine brain have only a limited capacity to self-renew, and the number of neurons they generate drastically declines with age. How cellular dynamics sustain neurogenesis and how alterations with age may result in this decline, are both unresolved issues. Therefore, we clonally traced neural stem cell lineages using confetti reporters in young and middle-aged adult mice. To understand underlying mechanisms, we derived mathematical population models of adult neurogenesis that explain the observed clonal cell type abundances. Models fitting the data best consistently show self renewal of transit amplifying progenitors and rapid neuroblast cell cycle exit.…
Vascular‐derived TGF‐β increases in the stem cell niche and perturbs neurogenesis during aging and following irradiation in the adult mouse brain
2012
Neurogenesis decreases during aging and following cranial radiotherapy, causing a progressive cognitive decline that is currently untreatable. However, functional neural stem cells remained present in the subventricular zone of high dose-irradiated and aged mouse brains. We therefore investigated whether alterations in the neurogenic niches are perhaps responsible for the neurogenesis decline. This hypothesis was supported by the absence of proliferation of neural stem cells that were engrafted into the vascular niches of irradiated host brains. Moreover, we observed a marked increase in TGF-β1 production by endothelial cells in the stem cell niche in both middle-aged and irradiated mice. I…
Stem cells, cancer stem-like cells, and natural products.
2012
Somatic stem cells can be found in many rapidly regenerating tissues, e.g., the skin, gastrointestinal mucosa, and hematopoietic system, but are also present at low numbers in non-regenerative organs such as the heart and brain. In these organs, somatic stem cells aid in normal tissue homeostasis and repair after injury as well as self-renewal and the generation of specific progenitor cells during differentiation. Cancer stem-like cells are a small subpopulation of self-renewing cells that are able to proliferate upon appropriate stimulation and differentiate into heterogeneous lineages in tumors. Modulation of the behavior of normal tissue stem cells and cancer stem-like cells is an emergi…