Complete blood count and acetylcholinesterase activity of lymphocytes of demyelinated and ovariectomized rats treated with resveratrol.

Resveratrol is a phytoestrogen that has many beneficial actions. This study aimed to evaluate the effect of resveratrol on the complete blood count (CBC) and the acetylcholinesterase (AChE) activity of lymphocytes of ovariectomized rats experimentally demyelinated by ethidium bromide (EB). Forty adult female Wistar rats (60 days, 200-220 g) were divided randomly into five groups (n = 4) to evaluate the demyelination phase and five groups (n = 4) to evaluate the remyelination phase. In each phase, the groups consisted of sham rats-G1; ovariectomized rats, not demyelinated, treated only with vehicle (ethanol 25%)-G2; demyelinated ovariectomized rats treated only with vehicle-G3; ovariectomized rats, not demyelinated, treated with resveratrol-G4; and demyelinated ovariectomized rats treated with resveratrol-G5. Only during the remyelination phase, CBC showed a significant difference (p < 0.05) in the number of monocytes between G2 and G5 groups. In the demyelination phase, there was a significant decrease (p < 0.05) in the AChE activity in the G4 group, while the G5 group was statistically similar to the G1, G2 and G4 groups. In the remyelination phase, there were no significant differences in the AChE activity among the groups. The treatment for 7 days with resveratrol with or without the experimental demyelization with EB appears to influence the AChE activity of lymphocytes, without changing the number of these cells in the circulation. However, in the remyelination phase, there seems to be stabilization in its effect on the lymphocyte AChE activity.

17-ß estradiol in the acetylcholinesterase activity and lipid peroxidation in the brain and blood of ovariectomized adult and middle-aged rats.

AIMS: To investigate the 17-ß estradiol in the acetylcholinesterase activity and lipid peroxidation in the brain and blood of ovariectomized rats of different ages. MAIN METHODS: Animals were randomly assigned into three experimental groups of each age (n=6). Control groups consisted of adult (sham-A) and middle-aged (sham-MA) female rats, ovariectomized adult (OVX-A) and middle-aged (OVX-MA) rats without estrogen therapy reposition, and ovariectomized adult (OVX+E2-A) and middle-aged (OVX+E2-MA) rats treated with 17-ß estradiol for 30days. After this period, AChE activity and lipid peroxidation were measured in the brain and blood. KEY FINDINGS: The AChE activity increased (p<0.05) in striatum (ST) in OVX-A, OVX+E2-A and OVX-MA, and hippocampus (HP) in OVX-MA. The enzyme activity decreased (p<0.05) in ST of OVX+E2-MA, and cerebral cortex (CC) in OVX+E2-A, OVX-MA and OVX+E2-MA. Blood AChE activity increased (p<0.05) in OVX+E2-A and decreased (p<0.05) in OVX-MA. Lymphocyte AChE activity increased (p<0.05) in OVX-A and OVX+E2-A and decreased (p<0.05) in OVX-MA. Lipid peroxidation increased (p<0.05) in ST of OVX-A, CC of OVX-A and OVX-MA, HP of OVX-A, and cerebellum (CE) of OVX-A, OVX-MA, and OVX+E2-MA. Lipid peroxidation decreased (p<0.05) in ST, CC and CE of OVX+E2-A, and ST and HP of OVX+E2-MA. Similar values of lipid peroxidation to control groups were found in ST and HP of OVX-MA, HP of OVX+E2-A and CC of OVX+E2-MA. SIGNIFICANCE: 17-ß estradiol is able to modulate the AChE activity and non-neuronal cholinergic response as well as to reduce lipid peroxidation. Its response is dependent on the age and brain structure analyzed.

Lipid peroxidation associated with anemia in rats experimentally infected with Trypanosoma evansi.

This study aimed to assess the plasma lipid peroxidation and the susceptibility of erythrocytes to in vitro peroxidation as indicators of oxidative damage in erythrocytes and their roles in the pathogenesis of anemia during the early acute phase of Trypanosoma evansi infection in rats. Fifty male Wistar rats were randomly distributed into seven groups: three trypanosome-infected groups (T(2), T(4) and T(6); n=10 animals per group) and four uninfected controls (C(0), C(2), C(4) and C(6); n=5 animals per group). Animals from trypanosome-infected groups were inoculated intraperitoneally with 10(6) trypanosomes. Blood samples were collected by cardiac puncture before infection (day 0; group C(0)) or on the 2nd (C(2) and T(2)), 4th (C(4) and T(4)) and 6th (C(6) and T(6)) day post-infection (dpi). Samples were analyzed for red blood cell (RBC) count, hemoglobin (Hb) concentration, packed cell volume (PCV), plasma malondialdehyde (MDA) and in vitro peroxidation of erythrocytes. The mean values of the hematological indices gradually decreased in the infected rats compared with the control. MDA was significantly increased (P<0.001) on the 6th dpi in infected versus control animals and was negatively correlated with PCV (P<0.001; R(2)=0.372). The values for erythrocyte in vitro peroxidation were higher for groups T(4) and T(6) than for the control rats (P<0.01). A positive correlation between erythrocyte peroxidation and MDA (P<0.001; R(2)=0.414) was observed. The results of this study indicate that T. evansi infection in rats is associated with oxidative stress, indicated by lipid peroxidation and oxidative damage in erythrocyte membranes, as demonstrated by in vitro peroxidation. This may be one of the causes of anemia in acute trypanosomosis.