LDN-193189 increases Hb levels in established turpentine-induced anemia. (A-B) Mice were injected with turpentine (5 mL/kg intrascapularly) or saline weekly for 3 weeks resulting in microcytic anemia in turpentine-injected mice (left panels; n = 5 per group, *P < .05 turpentine-injected vs saline-injected controls). After 3 weeks, turpentine-treated mice were treated daily with LDN-193189 (3 mg/kg IP) or vehicle, while intrascapular turpentine or saline injections continued for an additional 3 weeks. At 6 weeks, Hb levels (A) in turpentine-injected mice were less than those in saline-injected mice, while administration of LDN-193189 by itself had no significant effect, and administration of LDN-193189 in turpentine-injected mice increased Hb levels to a significant degree (right panel; n = 5 per group, 1-way ANOVA P = .005, #P < .05 turpentine-injected vs saline-injected controls, †P < .05 turpentine-injected vs turpentine-injected mice treated with LDN-193189). MCV (B) was persistently decreased as a result of turpentine injections after 6 weeks, and tended to improve with LDN-193189 treatment (right panel; n = 5 per group, 1-way ANOVA P = .0002, #P < .01 turpentine-injected vs saline-injected controls, †P = .1 turpentine-injected vs turpentine-injected treated with LDN-193189). Data shown are representative of 3 independent experiments.