Another study, using ovariectomized (OVX) rat models with streptozotocin- (STZ-) induced cognitive impairment, has shown that KPF was able to positively modulate the endogenous antioxidants, glutathione and superoxide dismutase (SOD), important against toxicity caused by reactive oxygen species (ROS) which contribute to the development of AD. This evidence concerns the gene SOD1 and Alzheimer disease.