O tratamento com curcumina reverte os déficits de memória nas tarefas de reconhecimento de objetos em ratas ovariectomizadas

Abstract

Menopause is characterized by the absence of menstruation and the main physiological change that a woman's body experiences is the drop in the hormone estrogen. Female sex hormones are closely linked to aging and the progression of neurological disorders, estrogen in the brain prevents the deterioration of cognitive abilities, thus evidencing its neuroprotective role. Turmeric has aroused interest in recent years as a therapeutic agent due to its anti-inflammatory properties. Curcumin, a bioactive compound of turmeric, has been highlighted for presenting a neuroprotective factor, thus, a potential compound that contributes to the improvement of brain functions. The objective of this work was to evaluate the effect of curcumin on object recognition memory in ovariectomized rats. Adult female Wistar rats were used. The animals were submitted to the surgical procedure for removal of the ovaries (ovariectomy - OVX) or submitted to simulated organ removal (celiotomy - SHAM). After surgery, the animals were separated into groups of 12 animals each, for the object recognition behavioral test. From 15 days after surgery, OVX and SHAM curcumin rats (OVX-C and SHAM-C) received curcumin via gavage at a dose of 50mg/Kg, or vehicle (OVX+V and SHAM+V), two other groups were hormonal controls where one group received 17β-estradiol (10 μg / kg) subcutaneously (OVX+E) and the other group received corn oil as a control (OVX+OM). The duration of treatment with curcumin was seventeen days, and on the 14th day the open field test was performed and on the fifteenth day the object recognition test was started in each group. At the end of the tests, the animals were euthanized, where they were decapitated to remove the hippocampus, for later analysis of the expression of BNDF, Synaptophysin and GFAP proteins by Western Blotting, and the adipose tissues and uterus were removed and weighed. As a result of the characterization of memory deficit, the ovariectomized group showed an increase in exploration time for the familiar object and a reduction in exploration time for the new object at 2 and 24 h in the object recognition test, when compared to the Sham group. As for the

animals that received treatment with estradiol and curcumin, an improvement in short and long- term memories was noted when compared to the OVX+vehicle group. Regarding body weight,

it is possible to note that the groups submitted to ovariectomy showed greater weight gain compared to the sham group, and the treatment with estradiol was able to reduce the weight of the animals, while curcumin did not show results in terms of reduction. of weight in OVX+C animals. Fat accumulation was not different in both groups, regardless of treatment. As for the uterus, the ovariectomized group had a lower weight, with the lack of estrogen being the factor that leads to the involution of this organ. Regarding the evaluation of the expression of BDNF, Synaptophysin and GFAP proteins, no differences were found between the OVX and Sham groups. We can conclude that curcumin treatment