Sporadic Alzheimer’s disease (SAD) is the most prevalent neurodegenerative disorder and it is characterized by progressive decline in memory and cognitive performance, which left unabated will likely affect 152 million people by 2050. Women represent more than two-thirds of patients with SAD worldwide, facing a higher risk for multimorbidity of brain disorders for which we have no effective therapies.
However, female animal models are usually excluded in preclinic research. Our aim was to evaluate the female brain disorder in a rat SAD model induced by intracerebroventricular injection of streptozotocin (icv-STZ).
We evaluated 4 animal groups: Sham, STZ, OVX and OVX+STZ (N=8). OVX and OVX+STZ groups were ovariectomized and, seven days later, STZ and OVX+STZ groups were injected with 3 mg/kg icv-STZ. Body weight of all rats was registered along the experiment every week. During the last two weeks until the end of the study (day 30 post icv-STZ), we performed several behavioural tests: species-typical behaviour (Marble Burying), object recognition memory (Novel Object Recognition), spatial memory (Barnes Maze), and depression-like behaviour (Forced Swim Test).
Our preliminary results show that STZ affected behavioural performance differently in the SAD model depending on the ovarian status of female rats. This verifies our hypothesis that ovarian steroid levels modify the impact of neurodegenerative effects induced by STZ icv.