Indirect and direct markers of alcohol exposure. (A) Ideally, biomarkers could be both sensitive and specific to alcohol exposure and also indicate the timing and amount of alcohol exposure. This figure shows the period of time, or detection window, during which alcohol consumption can be detected and the lowest levels of alcohol consumption detectable by current alcohol biomarkers. For example, fatty acid ethyl esters are detectable in a variety of biological samples, such as neonatal hair and meconium, for several months after exposure. (B) MicroRNAs (miRNAs) may serve as potential biomarkers. Using a sheep model, Dr. Rajesh Miranda has identified several miRNAs that are modified by ethanol. As shown in this panel, miR-9 expression was significantly increased in plasma from the ethanol-exposed pregnant female compared with the control female but significantly decreased in plasma from neonatal lamb compared with controls. Alterations in miR-9 may be indicative of alcohol exposure in the mother, but also may serve as a marker of alcohol-induced injury in the neonate.SOURCE: Figure 2(A): Bakhireva and Savage 2011. Figure 2(B): Modified from Balaraman et al. 2014.NOTE: * = significantly different from control.
