However, despite the lack of diabetes-induced OPN expression in BALB/c mice after 4 weeks of diabetes, in agreement with previous results in larger vessels [3], in vivo NFAT-inhibition for the duration of the experiment reduced the levels of OPN mRNA in retinal vessels regardless of the diabetic condition, indicating a potential NFAT-dependent regulation of OPN under basal conditions in this tissue. Here, SPP1 is linked to diabetes mellitus.