Beta-amyloid Formation, Memory and Learning Decline Following Long-term Ovariectomy Are Inhibited by Systemic Administration of Apigenin and β-estradiol

Abstract

Objective: The increase in the number of patients with Alzheimer's disease (AD) has led to numerous problems. The risk of developing AD increases in menopause women. Apigenin and is β-estradiol are effective antioxidant and neuroprotective agents. In order to study the combined effects of them on beta-amyloid plaque formation, memory, and learning in ovariectomized rats, the present study was designed. Methods: Forty-two Wistar rats were randomly assigned into 7 groups; ovariectomized (OVX), OVX + apigenin, OVX + β-estradiol, OVX + apigenin + β-estradiol, vehicle and surgical sham. Treatment was done with apigenin and β-estradiol. The formation of β-amyloid plaques, neuronal density in the hippocampus area, apoptosis, memory, and learning was studied. Results: Findings showed the significant formation of β-amyloid plaques in the (hippocampus) area of OVX animals and memory impairment. Apigenin and β-estradiol significantly reduced the number of β-amyloid plaques, as well as the reduction of symptoms of memory impairment and learning and decreased expression of Caspase-3 in treated animals. Conclusion: Accordingly, the combination of antioxidants with E2 could have more strong therapeutic effects for AD.

Neurogenesis in the rat neonate's hippocampus with maternal short‐term REM sleep deprivation restores by royal jelly treatment

“…Their brain was removed and kept in graded sucrose solution as the cryoprotective agent, by using a freezing microtome (Leica 3000 Germany) and coronal sections of 10 μm were prepared. Nissl staining was done as mentioned in our previous studies (Hassanzadeh et al., 2018; Jameie et al., 2021). By using Image J software, the neuronal number and density of the hippocampus number were studied.…”

The Beneficial Role of Apigenin against Cognitive and Neurobehavioural Dysfunction: A Systematic Review of Preclinical Investigations

“…All the studies showed that apigenin improved learning and memory, except for two studies. From the Morris Water Maze tests, eight studies showed that apigenin reduced escape latency [20,30], improved the time spent in the target quadrant [26][27][28]30], reduced first entry to the target quadrant and increased the number of crossings into the platform region [27]. Only one study reported the effect of apigenin on spatial memory using the Barnes test.…”

Effectiveness of Flavonoid-Rich Diet in Alleviating Symptoms of Neurodegenerative Diseases

“…As one of the most frequently consumed flavonoids from the flavones subgroup, apigenin (4′,5,7-trihydroxyflavone) is present in the highest amounts in parsley, celery, mint, chamomile, lavender, apples, onions, oranges, lemons, broccoli, and spinach. It has a positive effect on learning, memory, and locomotor activity, as well as revealing anxiolytic properties, weaking depressive behaviors, and improving sensorimotor and motor coordination in animals with cognitive disease and neurobehavioral deficits [ 144 , 145 , 146 , 147 ]. It has been found that apigenin reduces the reactivity of microglia in the hippocampus, which is important in the initiation and progression of neurodegenerative diseases, such as AD [ 148 ].…”