Synergistic effects of quercetin and regular exercise on the recovery of spatial memory and reduction of parameters of oxidative stress in an animal model of alzheimer's disease

It has widely been reported that the brain in Alzheimer's disease (AD) is affected by increased oxidative stress, and this may have a role in the pathogenesis of this disorder. Quercetin, a polyphenol extensively found in nature, has recently been considered. Also, physical activities have a paradoxical effect on brain function in older adults. Therefore, this study aimed at investigating the synergic effects of quercetin (as chemical treatment) and exercise (as physical treatment) on AD-induced learning and memory impairment. Fifty-six adult male Wistar rats were randomly assigned into one of the following eight groups (n=7): The Control, Sham (saline), AD (intracerebro-ventricular administration of streptozotocin (STZ)), AD+80 mg/kg Quercetin (STZ+Q80), Quercetin vehicle (1 % Ethanol)+STZ, Exercise pretreatment (EX)+STZ, Off the treadmill+STZ, and EX+Q80+STZ. Quercetin administration was done intraperitoneally for 21 days after STZ injection. The rats ran on the treadmill for one hour a day for 60 days at a speed of 20-22 m/min. After the treatment, the spatial memory and levels of oxidative stress parameters were evaluated. The results showed that STZ caused spatial memory impairment and increased oxidative stress in the hippocampus. Exercise pretreatment or Quercetin injection improved the spatial memory impairment and oxidative stress caused by STZ injection. However, the combination of quercetin and exercise pretreatment was more effective. It can be concluded that the combined exercise pretreatment and Quercetin injection affected the antioxidant defense system and improved STZ-induced memory impairment. Keywords:Alzheimer Disease; streptozotocin; quercetin; exercise; oxidative stress; hippocampu

The effect of intraperitoneally injection of Crystal meth on pituitary-gonad axis in adult male Rats

Background: Psychostimulant amphetamine (Ecstasy and Crystal meth or n-methyl-1- phenyl-propan-2- amine) abuse has been prevalent among the youth of Iran in recant years. These substances have many adverse and destructive effects on several organs. Therefore, this study was done to determine the effect of crystal meth on pituitary-gonadal axis in adult male rats. Material and Methods: 28 male adult rats were divided into four groups normal control group, and 5, 10 and 15 mg/kg bw Crystal meth-treatment groups. Animals in the Crystal meth-treated groups received 5, 10 and 15 mg/kg bw of Crystal meth intraperitoneally for seven days. After 7 days, blood sample was taken from the left ventricle of the animal's heart and LH, FSH and testosterone concentration were measured using ELISA kit. The SPSS-16 statistical software was used to analyze data. All data were analyzed by one-way analysis of variance (ANOVA) and the differences were considered significant at the p<0.05 level. Results: Testosterone hormone concentration significantly increased in experimental groups (10 and 15 mg/kg bw) in comparison with control group (P<0.05). Concentrations of FSH and LH in the experimental groups (5, 10 and 15 mg/kg bw) significantly reduced in comparison with control group (P<0.05). Conclusion: According to the hormonal examinations, we concluded that the use of Crystal meth causes destructive effects on the male pituitary-gonadal axis

Pretreatment of alcoholic extract of Scrophularia Striata on spatial memory and lipid peroxidation in male rats during crystal meth addiction

Background & Objective: Crystal meth damages the brain cells by inducing oxidative stress. In the present study the long- term injection effect of alcoholic extract of Scrophularia Striata on spatial memory and lipid peroxidation in male rats during crystal meth addiction was investigated.  Material & Methods: 49 male rats were divided in 7 groups including: control, sham (saline), crystal meth (5 mg/kg), Scrophularia Striata extract (100 and 200 mg/kg), pretreatment of Scrophularia Striata (100 mg/kg) + crystal meth (5 mg/kg), and pretreatment of Scrophularia Striata (200 mg/kg) + crystal meth (5 mg/kg).  Morris water maze test was used for assessing the spatial memory, and Malondialdehyde (MDA) was assayed as an index of lipid peroxidation. One-way analysis of variance (ANOVA) was used to analyze the data. Results: Spatial memory was significantly reduced by Crystal meth (P<0.001). Spatial memory was significantly improved by Scrophularia (100 and 200 mg/kg) in comparison to control group (P<0.05). Pretreatment of Scrophularia in both doses significantly improved the spatial memory in crystal meth group (P<0.05). MDA level significantly increased in crystal meth group (P<0.05), but pretreatment of Scrophularia significantly reduced the elevated level of MDA (P<0.05). Conclusion: It seems that, psychoactive drugs can impair spatial memory by inducing oxidative stress. Pretreatment of Scrophularia as an antioxidant, improves spatial memory which has been reduced by crystal meth

Intrahippocampal administration of Vitamin C and progesterone attenuates spatial earning and memory impairments in multiple sclerosis rats

It seems antioxidant and sex hormones are able to protect the multiple sclerosis (MS) rats against spatial memory reduction. Since sex hormones and oxidative stress are affective in the process of multiple sclerosis (MS), as well as cognitive functions, the study evaluates the effects of intrahippocampal injection of vitamin C and progesterone, alone or in combination on spatial memory in multiple sclerosis. Sixty-three (63) male Wistar rats were divided into nine groups (n = 7): control, (saline), sesame oil, lesion (ethidium bromide (EB)), vitamin C (1, 5 mg/kg), progesterone (0.1, 1 μg/μl) and combination therapy. In combination therapy, animals were treated with vitamin C (5 mg/kg) + progesterone (0.01 mg/kg). Animals in experimental groups received different treatments for 7 days. Characteristics of learning and spatial memory were assessed using Morris Water Maze (MWM). The results showed that intrahippocampal injection of ethidium bromide destroys MWM significantly (p&lt;0.05). Vitamin C (5 mg/kg), progesterone (0.1 mg/kg) and vitamin C (5 mg/kg) + progesterone (0.1 mg/kg) significantly decreased latency time and travelled distance (P&lt;0.05) in MS or lesion rats. In comparison with control group, the lesion group decreased and progesterone 0.1 mg/kg + vitamin C 5 mg/kg increased the time and distance in the target quadrant after the platform was removed. In comparison with lesion group, vitamin C (1 and 5 mg/kg), progesterone (0.1 and 1 mg/kg) and vitamin C + progesterone effective doses increased the time and distance in the target quadrant after the platform was removed. The results showed that multiple sclerosis rats had a decreased travelled distance and time spent in target quadrant to find the hidden platform in a MWM task. Vitamin C and progesterone alone improved spatial memory in comparison to lesion group. Effective doses of vitamin C + effective dose of progesterone had more improving effect on memory.Keywords: Neuroscience, Neurosteroid, Antioxidant, Demylination, Progesterone, Learning and memory impairments, Multiple sclerosis rat

Intraperitoneal injection of buprenorphine on anxiety-like behavior and alteration in expression of Gfap and Nrf2 in methamphetamine treated rats

The effects of buprenorphine (BUP) on anxiety-like behavior and the expression of the glial fibrillary acidic protein (Gfap) and nuclear factor erythroid 2-related factor 2 (Nrf2) in methamphetamine (METH)-treated rats were investigated in this study. Twenty-eight male Wistar rats were randomly divided into four groups including control (saline), METH (10.00 mg kg(-1)), BUP (10.00 mg kg(-1)), and BUP+METH groups and treated for five days. On the final day of treatment, gene expression levels and anxiety were evaluated using elevated plus-maze (EPM). According to the results, five days of METH injection reduced open arm exploration in the EPM. In contrast, the open arm entries and the time spent in the open arms were increased in the BUP+METH group compared to the METH group. The expression levels of Gfap and Nrf2 were lower in METH-treated rats compared to controls, whereas Gfap and Nrf2 expression levels were higher in the METH+BUP-treated rats compared to the METH-treated rats, however, it was similar to the controls. These findings suggested that co-administration of BUP+METH could decrease anxiety-like behavior through increasing the activity of the antioxidant protection system and might have therapeutic potential for preventing anxiety in METH users. (c) 2022 Urmia University. All rights reserved

17-β estradiol Attenuated Hippocampus Oxidative Stress in an Ethidium Bromide-Induced Multiple Sclerosis Model among Adult Male Rats

Introduction: Multiple sclerosis (MS) is a disease of the central nervous system in which myelin is destroyed. Oxidative stress and subsequent apoptosis are recognized as factors involved in the pathogenesis of MS.  On the other hand, 17-β-estradiol is well known  for its anti-oxidant properties. Therefore, this study aimed to investigate the effect of 17-beta-estradiol on oxidative stress parameters in the experimental model of MS.   Materials & Methods: This study was conducted on 49 Wistar male rats cannulating into the CA1 area of hippocampus. The rats were randomly divided into following groups (n=7): control group, sham group, MS group, estradiol groups, MS+estradiol groups. MS model was induced by intrahippocampal injection of ethidium bromide and estradiol was injected as a pretreatment for 5 days. At the end of experiments, the levels of oxidative stress parameters, such as MDA, Glutathione, and antioxidant enzymes (Glutathione peroxidase, Superoxide dismutase and Catalase)were measured in this study.   Findings: The microinjection of ethidium bromide increased the oxidative capacity and reduced the antioxidant enzyme (SOD GPx and CAT) activity (P<0.05). The pre-treatment of 17-beta-estradiol prevented an increase in oxidative capacity and decreased the activity of antioxidant enzymes in the experimental groups (P<0.05).   Discussion & Conclu sions: The 17-beta-estradiol, as a potent antioxidant, is likely to prevent the increase of oxidative stress indices in the experimental model of MS by removing reactive oxygen species and clearing the tissues from free radicals

Effect of Alcoholic Extract of Rosa canina on Hepatic Tissue and Hepatic Enzymes Activity in Diabetic Rats

Background & aim: Nowadays because of difficulty in the supply and injection of insulin and blood sugar reducing drugs and considering the side effects of chemical drugs, researcher&rsquo;s attention is drawn to using herbal medicines. Liver is one of the organs affected by diabetes in different functional aspects. The purpose of this research was studying the effect of Rosa canina extract on reducing the adverse effects and improving diabetes symptoms related to histophysiology, amount of biochemical serum factors and liver enzymes in male rats. Methods: 32 male Wistar rats, weighed 200-220 gr, were divided into 4 groups. Diabetes was induced by intraperitoneal injection of STZ (60mg/kg). The period of experiments was 4 weeks. At the end of experiments, the rats were sacrificed and their serums were collected for measurement of liver enzymes. Also, histological sampling of liver was done. Statistical analysis was performed using analysis of variance (one-way ANOVA). Results: The results of this study showed that treatment with ethanol extract of Rosa canina led to significant reduction of liver enzymes in the Rosa extract-treated groups in comparison with the diabetic group, indicating the protective effect of alcoholic extract of Rosa canina on liver tissue against diabetes-induced damages. In liver histopathology, a distinct fat change in the lobular center areas was created in the diabetic group. Pathological changes were not significant in the liver of the Rosa extract-treated groups; liver in this group was relatively healthier than in diabetic group. Conclusions: Rosa extract improved this organ's function in STZ-induced diabetic rats by reducing serum biomarkers of liver pathology and reducing histological damages

Analgesic Effect of 17β-Estradiol on Nucleus Paragigantocellularis Lateralis of Male Rats Mediated Via GABAA Receptors

Introduction: Beside its autonomic functions, the nucleus paragigantocellularis lateralis (LPGi) is involved in the descending pain modulation. 17&beta;-Estradiol is a neuroactive steroid found in several brain areas such as LPGi. Intra-LPGi microinjection of 17&beta;-estradiol can elicit the analgesic responses. 17&beta;-Estradiol modulates nociception by binding to estrogenic receptors as well as allosteric interaction with other membrane-bound receptors like GABAA receptors. This study aimed to examine the role of GABAA receptors in the pain modulating effect of intra-LPGi injection of 17&beta;-estradiol. Methods: To study the antinociceptive effects of 17&beta;-estradiol, cannulation into the LPGi nucleus of male Wistar rats was performed. About 500 nL of drug was administered 15 minutes prior to formalin injection (50 &mu;L of 4%). Then, formalin-induced flexing and licking behaviors were recorded for 60 minutes. For evaluating the role of GABAA receptors in the estradiol-induced pain modulation, 17&beta;-estradiol was administered into the LPGi nucleus 15 minutes after the injection of 25 ng/&mu;L bicuculline (the GABAA receptor antagonist). Then, the formalin-induced responses were recorded. Results: The results of the current study showed that intra-LPGi injection of 17&beta;-estradiol decreased the flexing duration in both phases of formalin test (P<0.001); but it only attenuated the second phase of licking behavior (P<0.001). 17&beta;-estradiol attenuated the second phase of formalin test of both behaviors (P<0.001). Bicuculline prevented the antinociceptive effect of intra-LPGi 17&beta;-estradiol in both first and second phases of formalin-induced responses (P<0.001). Conclusion: According to the results of this study, the analgesic effect of intra-LPGi 17&beta;-estradiol on the formalin-induced inflammatory pain might be mediated via GABAA receptors.&nbsp

Analgesic Effect of 17β-Estradiol on Nucleus Paragigantocellularis Lateralis of Male Rats Mediated Via GABAA Receptors

Introduction: Beside its autonomic functions, the nucleus paragigantocellularis lateralis (LPGi) is involved in the descending pain modulation. 17&beta;-Estradiol is a neuroactive steroid found in several brain areas such as LPGi. Intra-LPGi microinjection of 17&beta;-estradiol can elicit the analgesic responses. 17&beta;-Estradiol modulates nociception by binding to estrogenic receptors as well as allosteric interaction with other membrane-bound receptors like GABAA receptors. This study aimed to examine the role of GABAA receptors in the pain modulating effect of intra-LPGi injection of 17&beta;-estradiol. Methods: To study the antinociceptive effects of 17&beta;-estradiol, cannulation into the LPGi nucleus of male Wistar rats was performed. About 500 nL of drug was administered 15 minutes prior to formalin injection (50 &mu;L of 4%). Then, formalin-induced flexing and licking behaviors were recorded for 60 minutes. For evaluating the role of GABAA receptors in the estradiol-induced pain modulation, 17&beta;-estradiol was administered into the LPGi nucleus 15 minutes after the injection of 25 ng/&mu;L bicuculline (the GABAA receptor antagonist). Then, the formalin-induced responses were recorded. Results: The results of the current study showed that intra-LPGi injection of 17&beta;-estradiol decreased the flexing duration in both phases of formalin test (P<0.001); but it only attenuated the second phase of licking behavior (P<0.001). 17&beta;-estradiol attenuated the second phase of formalin test of both behaviors (P<0.001). Bicuculline prevented the antinociceptive effect of intra-LPGi 17&beta;-estradiol in both first and second phases of formalin-induced responses (P<0.001). Conclusion: According to the results of this study, the analgesic effect of intra-LPGi 17&beta;-estradiol on the formalin-induced inflammatory pain might be mediated via GABAA receptors.&nbsp

The effect of ethanolic extract of Ferula szowitsiana on cognitive deficits and lipid peroxidation induced by ethidium bromide in experimental model of MS

Introduction: The aim of this study was to investigate the effect of short-term microinjection of Ferula szowitsiana extract on the process of spatial memory and lipid peroxidation in the hippocampus in an experimental model of Multiple Sclerosis (MS). Methods: In this experimental study, 35 male Wistar rats were randomly divided into five groups. Each group has 7 rats. These groups were included control, sham, model of MS and MS groups with plant extract treatments. In the experimental model of MS groups, induction of MS was carried out by single injection of ethidium bromide (EB) into the hippocampus. One week after MS induction by EB (0.01 %), the MS groups were treated by Ferula szowitsiana extract (5 and 10 μg/rat) for 3 consecutive days. Finally following the treatment period, for measuring spatial memory, Morris Water Maze test was carried out and the hippocampus of both sides were dissected and used for measurement of Malondialdehyde (MDA). Results: The results showed that in the experimental model of MS group travelled distance (1022.44±53.29) and escape latency (41.30±3.29) increased compared to travelled distance (885.94±29.56) and escape latency (36.26±0.65) in the control group (p<0.001). Short-term treatment by Ferula szowitsiana extract in this models decreased the travelled distance (838.39±24.16) and escape latency (39.87±1.24) (P<0.001). MDA increased in the experimental model of MS group (3.8±0.51) compared to the control group (0.68±0.13) (p<0.001) and in the Ferula treated group (0.34±0.04) decreased compared to the MS animals (P<0.001). Conclusion: Treatment with Ferula szowitsiana extract is able to prevent memory and learning reduction, through inhibition of lipid peroxidation in an experimental model of MS