محمد پاک هاشمی

Polycystic ovarian syndrome (PCOS) is a prevalent disorder in women during their reproductive age. Besides, PCOS causes different abnormalities such as metabolic dysfunctions and behavioral signs. Both medications and life style modifications such as exercising are beneficial in PCOS treatment. In this study the effects of a 4-week endurance training on the improvement of behavioral consequences of PCOS in female rats under the administration of letrozole were examined.

In this study 30 female Wistar rats were divided into 3 groups, as follows. Control group: healthy animals. PCOS group: animals treated with letrozole (oral, 21 days). PCOS group + exercise: PCOS was induced and concurrently, exercise protocol (4 weeks) was performed on rats. To assess the anxiety-like behaviors, the elevated plus maze and open-field tests were used.

PCOS rats showed significant anxiety-like behaviors in the elevated plus maze (decrease in open arm time and entries percent). Open field test also showed anxiety in PCOS rats compared with the control animals (decrease in the inner time, p<0.05). Exercise protocol in PCOS rats significantly reduced anxiety in both tests.

4-week endurance exercise has protective effects against anxiety-like behaviors due to PCOS in female rats.

Metformin (MET) as an oral antidiabetic drug has pleiotropic effects such as antioxidative and neuroprotective properties. In the current study we aimed to investigate the probable effects of Pretreatment MET therapy in global ischemia-reperfusion in rats.

In this study, 40 male Wistar rats (200-220 g) were used. Animals were randomly divided into four groups of ten: sham group, ischemic group, ischemic + metformin group and metformin group. MET was administered orally at doses of 100 for 14 days then the rats underwent global ischemia-reperfusion and the treatment continued for 7 days. Depressive-like behavior was assessed by forced swimming test. Cognitive function was evaluated by Y-maze continuous alternation task and Morris water maze. The brains were assessed for the activity of superoxide dismutase (SOD) as well as level of brain-derived neurotrophic factor (BDNF).

global ischemia-reperfusion caused depression and declined the cognitive function (p<0.001( as well as BDNF (p<0.001( level and SOD (p<0.01 (activity. Pretreatment with MET reduced the depressive-like behavior (p<0.05( and attenuated the cognitive impairments (p<0.01( in ischemic rats. Moreover, MET increased the BDNF (p<0.001( level in the brains of ischemic animals

Our results recommended that chronic pretreatment MET therapy could improve behavioral disorders following global ischemia-reperfusion and could be used as a novel therapeutic approach for the treatment of brain ischemic conditions.

Aging is a complex process and is considered as a risk factor for many diseases such as hypertension, Alzheimer, cancer, depression and anxiety. Recently, it has been shown that metformin, an anti-diabetic drug, has important neurological effects such as preventing memory loss, stroke, anxiety, inflammation and seizures. Therefore, the aim of this study was investigating the effects of metformin on some cognitive factors in elderly male rats.

24 rats (22 months) were randomly divided into 3 groups (n=8). The first group was the control group that received water orally, the second group received metformin 1 mg/kg orally and the third group received metformin 10 mg/kg orally. After treatment for 40 days (once daily), behavioral tests, including Y-maze, elevated plus maze and depression test were performed on animals. Results were analyzed using GraphPad Prism version 6 and One-way ANOVA followed by Tukey-post hoc test.

The results of this study showed that metformin at a dose of 10 mg/kg significantly reduced anxiety (P<0.001) and depression (P<0.001) in older animals. Metformin at a dose of 1 mg/kg failed to improve aging-related disorders in this model.

Metformin at a dose of 10 mg/kg can reduce the quality of life by reducing anxiety and depression.

Chronic morphine use leads to structural changes in the brain. Some studies have shown the antioxidant and neuroprotective effects of Epigallocatechin gallate (EGCG) as a main polyphenol of green tea. Therefore, the aim of this study was to investigate the effect of EGCG on working memory in morphine-treated rats.

In this experimental study, 32 male Wistar rats were divided into 4 experimental groups (8 rats in each group): 1- control; 2- Morphine group (the animals received 40 mg/kg morphine for 4 weeks, once a day, s.c.); 3 and 4- Morphine + EGCG, the animals received morphine (40 mg/kg, 4 weeks, once a day, s.c.) and EGCG (5 and 50 mg/kg, once a day, i.p.). To evaluate the working memory, Y-maze spontaneous alternation was used. To measure the level of TNF-α protein expression in brain hippocampus tissue, the western blot test was used. One-way ANOVA with Tukey’s post hoc test was used for data analysis.

Intraperitoneal morphine injection resulted in working memory deficits and increased TNF-α protein expression levels compared to the control group (p<0.001). Moreover, intraperitoneal injection of 50 mg/kg EGCG in morphine treated rats significantly improved working memory (p<0.01) and decreased TNF-α protein expression level (p<0.05) compared to solely morphine treated group.

EGCG improved morphine induced working memory deficits in rats.