Hydroxyurea Induces Bone Marrow Mesenchymal Stromal Cells Senescence and Modifies Cell Functionality In Vitro

Abstract

Hydroxyurea (HU) is an antineoplastic agent that functions as an antimetabolite compound by inhibiting the ribonucleotide reductase. HU acts mainly as a cytostatic drug that through DNA replication stress may trigger a premature senescence-like cell phenotype, though its influence on bone marrow-derived mesenchymal stem/stromal cell (BMMSC) functions has not elucidated yet. Our results indicate that HU inhibits the growth of human BMMSC alongside senescence-like changes in both morphology and replicative potential, provokes cell cycle arrest at the S phase without affecting cellular viability and induces the expression of senescence-associated β-galactosidase and p16INK4. Moreover, HU-induced senescent BMMSC, although they did not change MSC markers expression, exhibited reduced capacity osteogenic and adipogenic differentiation. Conversely, HU treatment increased immunoregulatory functions of BMMSC compared with untreated cells and determined by T-cell proliferation. Interestingly, HU did not influence the capacity of BMMSC to induce monocytic myeloid-derived suppressor cells. Thus, these results suggest that HU improves the BMMSC functions on the T-cell inhibition and preserves their interaction with myeloid cell compartment. Mechanistically, BMMSC under HU treatment displayed a downregulation of mTOR and p38 MAPK signaling that may explain the reduced cell differentiation and increased immunomodulation activities. Together, the results obtained in this investigation suggest that HU by inducing senescence-like phenotype of BMMSC influences their cellular differentiation and immunoregulatory functions.

Ratiometric Fluorescent Probe for Real-Time Detection of β-Galactosidase Activity in Lysosomes and Its Application in Drug-Induced Senescence Imaging

“…It is well known that β-gal is overexpressed in senescent cells; therefore, the senescent cells were selected as a research model for β-gal activity. HU is a water-soluble antiproliferative agent, which can inhibit the antimetabolic substances of ribonucleotide reductase. , Ribonucleotide reductase leads to the depletion of deoxyribonucleotides and significantly reduces cell proliferation, thus inducing cell senescence of healthy cells and cancer cells in vitro . Therefore, three different cell lines were used, PC-12 (Figure S15a), Hep G2 (Figure a), and RAW 264.7 cells (Figure S16a), for living cell senescence experiments.…”

“…Studies have shown that long-term injection and absorption of d -galactose can cause symptoms similar to natural aging. − d -Galactose induces senescence by reducing respiratory chain enzyme activity and ATP synthesis, leading to mitochondrial dysfunction and increasing ROS production . HU is also considered to be a drug that causes senescence and exerts an antimetabolic compound effect by inhibiting ribonucleotide reductase . Therefore, D-galactose- and HU-induced living mice senescence were used as the model for in vivo imaging.…”

“…45 HU is also considered to be a drug that causes senescence and exerts an antimetabolic compound effect by inhibiting ribonucleotide reductase. 35 Therefore, Dgalactose-and HU-induced living mice senescence were used as the model for in vivo imaging.…”

Adult Stem Cells in Aging

“…Moreover, chemotherapy is known as an inducer of changes in both hematopoietic compartments and MSC functions. The authors investigated how hydroxyurea, an inhibitor of ribonucleotide reductase, alter human MSC differentiation and immunosuppressive functions [ 7 ]. This study showed that hydroxyurea induced MSC senescence including cell proliferation arrest, which suggests a potential “therapy-induced senescence” effect.…”