Figure 4.

Resistin gene expression is not altered in cardiomyocytes but is induced dramatically by doxorubicin in macrophages. A, In neonatal cardiomyocytes isolated from Hum-Retn mice, gene expression of hRetn was not significantly induced by doxorubicin (1μM) in vitro. B, Peritoneal macrophages harvested from 10- to 12-week-old male Hum-Retn mice and then treated with doxorubicin (10μM) showed a 40-fold increase in resistin gene expression vs vehicle. C, Comparing multiple tissue and cell types revealed that human resistin mRNA expression levels were greatest in peritoneal macrophages (Mϕ) compared with neonatal cardiomyocytes (cm) or LV tissue. hRetn expression was 40-fold greater in untreated macrophages than LV tissue from vehicle-treated mice and 2000 times greater in doxorubicin-treated macrophages than LV tissue from doxorubicin-treated mice. All gene expression data are normalized to 36B4 expression. Mean + SEM, n = 5 per group; ‡, P < .05 doxorubicin vs vehicle. veh, vehicle; dox, doxorubicin.