The effects of protocatechuic acid and alpha tocopherol combination on aluminum-induced in vivo alzheimer model

Alzheimer's disease (AD) is the most common type of dementia in the community. Among the causes of this disease, which is characterized by neurofibrillary tangles and amyloid beta plaques formed in the brain, exposure to aluminum (Al), a pro-oxidant, has come to the fore in recent studies. Al-induced oxidative stress increases the formation of amyloid beta plaques in the brain and plays an important role in the progression of AD. In this thesis study, the effects of Vit E, which is known to be effective in preventing early symptoms of AD, when applied in combination with protocatechuic acid (PCA), which is a powerful antioxidant molecule that can cross the blood brain barrier, and especially with other antioxidant molecules, in the model of AD induced by AD and researched with applications made together. In the study, 48 male Sprague Dawley rats weighing between 200-225 g were used (n=6). The duration of the experiment was planned as 6 weeks (42 days). AlCl3 (70 mg/kg/day) was administered to rats by intraperitoneal route for 28 days. PCA and Vit E (water-soluble D-alpha tocopherol form) applications were applied for 14 days starting from the 28th day. PCA 5 mg/kg/day i.p. aspect; Vit E is administered i.p. at a dose of 50 mg/kg/day has been applied. Passive avoidance test was performed to control dementia, and AChE was measured to control synaptic transmission. Oxidative stress level and related responses were determined by measuring CAT, SOD and MDA parameters. Histological changes in the brain tissue were examined by light microscopy. Tau hyperphosphorylation was determined by indirect immunofluorescence method. DNA damage was measured by the single cell gell electrophorosis method. According to the findings, PCA and VitE; It showed a regulatory effect by significantly reducing the oxidative stress and AChE activity increased as a result of Al exposure in all applications performed together and separately. PCA and Vit E applications also significantly reduced DNA damage, revealed hyperphosphorylated tau accumulation and the progression of other pathological formations in the brain, with different levels of preventive and curative effects in terms of different parameters. The dementia status in the experimental groups was consistent with the biochemical and microscopic findings. As a result, PCA and Vit E are significantly and importantly effective in the regulation of early AD pathologies induced by Al exposure in rat brain tissue and in the prevention of new pathological formations, without any notable difference, whether they are applied separately or together.