SELENOS and hyperinsulinemic hypoglycemia, familial, 4: Selenoproteins are essential for human health, specifically for their inherent antioxidant properties.[116, 117] Defective selenoproteins result in the physiological accumulation of ROS, which can disrupt the antioxidant system and cause cell death.[118, 119, 120] Selenoprotein deficiency specifically worsens myocardial ischemic disease by increasing the cardiomyocyte ROS concentration.