Lysosomes and Their Role in Regulating the Metabolism of Hematopoietic Stem Cells

Abstract

Hematopoietic stem cells (HSCs) have the capacity to renew blood cells at all stages of life and are largely quiescent at a steady state. It is essential to understand the processes that govern quiescence in HSCs to enhance bone marrow transplantation. It is hypothesized that in their quiescent state, HSCs primarily use glycolysis for energy production rather than mitochondrial oxidative phosphorylation (OXPHOS). In addition, the HSC switch from quiescence to activation occurs along a continuous developmental path that is driven by metabolism. Specifying the metabolic regulation pathway of HSC quiescence will provide insights into HSC homeostasis for therapeutic application. Therefore, understanding the metabolic demands of HSCs at a steady state is key to developing innovative hematological therapeutics. Lysosomes are the major degradative organelle in eukaryotic cells. Catabolic, anabolic, and lysosomal function abnormalities are connected to an expanding list of diseases. In recent years, lysosomes have emerged as control centers of cellular metabolism, particularly in HSC quiescence, and essential regulators of cell signaling have been found on the lysosomal membrane. In addition to autophagic processes, lysosomal activities have been shown to be crucial in sustaining quiescence by restricting HSCs access to a nutritional reserve essential for their activation into the cell cycle. Lysosomal activity may preserve HSC quiescence by altering glycolysis-mitochondrial biogenesis. The understanding of HSC metabolism has significantly expanded over the decade, revealing previously unknown requirements of HSCs in both their dividing (active) and quiescent states. Therefore, understanding the role of lysosomes in HSCs will allow for the development of innovative treatment methods based on HSCs to fight clonal hematopoiesis and HSC aging.

Advances in Understanding the Links between Metabolism and Autophagy in Acute Myeloid Leukemia: From Biology to Therapeutic Targeting

“…This protective mechanism affects HSC quiescence and function by limiting cytokine receptor signaling and autophagy [54]. The high number of lysosomes and their activity are critical in order to complete mitochondrial clearance in HSCs and to preserve their quiescent characteristics [55,56].…”

Identification and Validation of Eight Lysosomes-Related Genes Signatures and Correlation with Immune Cell Infiltration in Lung Adenocarcinoma

“…To better understand the mechanisms by which lysosomes affect cancer development, A GSVA analysis was performed using the de ned gene sets (KEGG and Hallmark), and glycolysis, mTOR targets, DNA repair, and myc-targets were identi ed as lysosome-related pathways in cluster 2. Previous studies showed that lysosomal activity may play a role in preserving the quiescence of hematopoietic stem cells by modifying glycolysis-mitochondrial biogenesis 23 . In addition, the mTOR targets, DNA repair, and myctargets are all involved in the autophagic process and are essential for lysosome formation and transformation [24][25][26] .…”

Identification and validation of eight lysosomes-related genes signatures and correlation with immune cell infiltration in lung adenocarcinoma

“…To better understand the mechanisms by which lysosomes affect cancer development, A GSVA analysis was performed using the defined gene sets (KEGG and Hallmark), and glycolysis, mTOR targets, DNA repair, and myc-targets were identified as lysosome-related pathways in cluster 2. Previous studies showed that lysosomal activity may play a role in preserving the quiescence of hematopoietic stem cells by modifying glycolysis-mitochondrial biogenesis [ 33 ]. In addition, the mTOR targets, DNA repair, and myc-targets are all involved in the autophagic process and are essential for lysosome formation and transformation [ 34 – 36 ].…”