title: Hydroquinone and catechol reduce the frequency of progenitor B lymphocytes in mouse spleen and bone marrow.
abstract: Hydroquinone and catechol are two metabolites of benzene that are potential inducers of hematotoxicity. We investigated the in vivo toxicity of these metabolites toward the development of polyclonal, plaque-forming cells (PC-PFC) from progenitor B lymphocytes. Dextran sulfate (DxS), lipopolysaccharide (LPS), or the two mitogens combined (DxS + LPS) were used to induce proliferation and maturation of these progenitors to PC-PFC. Groups of 4 C57BL/6 mice were exposed to 2 daily doses, either intravenously or intraperitoneally, of hydroquinone (100 mg/kg) or catechol (75 mg/kg) for 3 consecutive days. Spleen and marrow cells were harvested for culture 1 day later. The results demonstrated that both metabolites were cytotoxic to spleen cells. Hydroquinone (100 mg/kg) also reduced marrow cellularity, whereas catechol (75 mg/kg) did not significantly affect marrow cellularity. Each compound reduced the frequency of PC-PFC developed from the spleens and marrows of treated mice, but only catechol selectively inhibited the maturation of LPS-activated marrow progenitors into end-stage PC-PFC. These experiments demonstrate the immunotoxic potential of hydroquinone and catechol in vivo through the reduction of progenitor B lymphocytes and suggest that inhibition of precursor cell maturation may play a significant role in the hematotoxicity observed after chronic exposure to benzene.
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000187:drug effects*; D001854:Bone Marrow Cells; D002396:Catechols / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D003114:Colony-Forming Units Assay; D006412:Hematopoietic Stem Cells / Q000187:drug effects*; D006873:Hydroquinones / Q000494:pharmacology*; D066298:In Vitro Techniques; D051379:Mice; D008810:Mice, Inbred C57BL; D008934:Mitogens / Q000494:pharmacology; D013154:Spleen / Q000166:cytology*
chemical_list: D002396:Catechols; D006873:Hydroquinones; D008934:Mitogens; C031927:hydroquinone