Effects of p38 MAP kinase inhibitors on the differentiation and maturation of erythroid progenitors.
In rodents, p38 MAP kinase inhibitors (p38is) induce bone marrow hypocellularity and reduce reticulocyte and erythrocyte counts. To identify target cell populations affected, a differentiating primary liquid erythroid culture system using sca-1(+)cells from mouse bone marrow was developed and challenged with p38is SB-203580, SB-226882, and SB-267030. Drug-related alterations in genes involved at different stages of erythropoiesis, cell-surface antigen expression (CSAE), burst-forming unit erythroid (BFU-E) colony formation, and cellular morphology (CM), growth (CG), and viability were evaluated. CSAE, CM, and decreases in BFU-E formation indicated delayed maturation, while CG and viability were unaffected. Terminal differentiation was delayed until day 14 versus day 7 in controls. CSAE demonstrated higher percentages of sca-1(+)cells after day 2 and reduced percentages of ter119(+) cells after day 7 in all treated cultures. Real-time reverse transcriptase polymerase chain reaction revealed a transient delay in expression of genes involved at early, intermediate, and late stages of erythropoiesis, followed by rebound expression at later time points. Results demonstrate p38is do not irreversibly inhibit erythrogenesis but induce a potency-dependent, transient delay in erythropoietic activity. The delay in activity is suggestive of effects on sca-1(+)bone marrow cells caused by alterations in expression of genes related to erythroid commitment and differentiation resulting in delayed maturation.
Dalmas
Deidre A
DA
Department of Safety Assessment, GlaxoSmithKline, King of Prussia, Pennsylvania 19406, USA. deidre.a.dalmas@gsk.com
Tierney
Lauren A
LA
Zhang
Cindy
C
Narayanan
Padma K
PK
Boyce
Rogely W
RW
Schwartz
Lester W
LW
Frazier
Kendall S
KS
Scicchitano
Marshall S
MS
D000818:Animals; D000950:Antigens, Ly / Q000378:metabolism; D051792:Basic Helix-Loop-Helix Proteins / Q000378:metabolism; D001854:Bone Marrow Cells / Q000187:drug effects; D018929:Cell Culture Techniques; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003114:Colony-Forming Units Assay; D015672:Erythroid Precursor Cells / Q000187:drug effects; D004920:Erythropoiesis / Q000187:drug effects* / Q000235:genetics*; D050989:GATA2 Transcription Factor / Q000378:metabolism; D007093:Imidazoles / Q000494:pharmacology*; D016130:Immunophenotyping; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D051379:Mice; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D011725:Pyridines / Q000494:pharmacology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000073942:T-Cell Acute Lymphocytic Leukemia Protein 1; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors*
D000950:Antigens, Ly; D051792:Basic Helix-Loop-Helix Proteins; D050989:GATA2 Transcription Factor; D007093:Imidazoles; D008565:Membrane Proteins; D047428:Protein Kinase Inhibitors; D011518:Proto-Oncogene Proteins; D011725:Pyridines; D000073942:T-Cell Acute Lymphocytic Leukemia Protein 1; D048051:p38 Mitogen-Activated Protein Kinases; C494712:Gata2 protein, mouse; C074650:Ly6a protein, mouse; C489366:Tal1 protein, mouse; C093642:SB 203580