Effects of environmental stressors on stem cells

Abstract

Environmental toxicants are ubiquitous, and many are known to cause harmful health effects. However, much of what we know or think we know concerning the targets and long-term effects of exposure to environmental stressors is sadly lacking. Toxicant exposure may have health effects that are currently mischaracterized or at least mechanistically incompletely understood. While much of the recent excitement about stem cells (SCs) focuses on their potential as therapeutic agents, they also offer a valuable resource to give us insight into the mechanisms and risks of toxicant effects. Not only as a response to the increasing ethical pressure to reduce animal testing, SC studies allow us valuable insight into the true effects of human exposure to environmental stressors under controlled conditions. We present a review of the history of publications on the effects of environmental stressors on SCs, followed by a consolidation of the literature over the past five years on a subset of key environmental stressors of importance to human health and their effects on both embryonic and tissue SCs. The review will make constructive suggestions as to areas of toxicant research where further studies are needed, as well as making indications of the potential utility for advancing knowledge and directing research on environmental toxicology.

Brain tumors: Cancer stem-like cells interact with tumor microenvironment

“…The pathways mediating the stemness of NSCs, such as Notch, WNT/β-catenin, and Hedgehog signaling, are also critical in glioma stem-like cells to drive tumorigenicity[ 14 , 15 ]. Recently, novel therapeutic approaches are established with the goal of not only reducing the tumor burden but also targeting CSCs involved[ 16 ].…”

Characterizing the Low-Dose Effects of Methylmercury on the Early Stages of Embryo Development Using Cultured Human Embryonic Stem Cells

“…1998 ). Genetic or epigenetic alterations in hESCs induced by environmental stressors, if they occur in vivo , may affect the fate and development of the embryo and the health status of the individual later in life ( Worley and Parker 2019 ). MeHg exposures have been associated with a higher number of abnormal blastocysts ( Kajiwara and Inouye 1986 ) and blastocyst degeneration ( Spindle and Matsumoto 1987 ) in mice.…”

“…Each of these lineages then further differentiates into cells of different organs and systems; examples of this differentiation include the endoderm forming gut epithelial cells, pancreas, and hepatocytes; the ectoderm forming neural epithelium, embryonic ganglia, and stratified squamous epithelium; and the mesoderm forming cartilage, bone, and smooth and striated muscles (Li et al 2015;Thomson et al 1998). Genetic or epigenetic alterations in hESCs induced by environmental stressors, if they occur in vivo, may affect the fate and development of the embryo and the health status of the individual later in life (Worley and Parker 2019). MeHg exposures have been associated with a higher number of abnormal blastocysts (Kajiwara and Inouye 1986) and blastocyst degeneration (Spindle and Matsumoto 1987) in mice.…”

Mercury Chloride Impacts on the Development of Erythrocytes and Megakaryocytes in Mice

“…Environmental pollutants can significantly impact hematopoiesis [ 17 , 18 ]. We previously reported that heavy metals in the living environment such as cadmium, lead, and Hg significantly influenced the function of HSCs and the committed progenitors, leading to aberrant myelopoiesis and/or lymphopoiesis [ 19 , 20 , 21 , 22 , 23 ].…”