Role of Hippocampal 5-HT6 Receptors in Glucocorticoid-Induced Enhancement of Memory Consolidation in Rats

Introduction:

of the study: Post-training administration of glucocorticoids enhance memory consolidation of inhibitory avoidance learning. Given the involvement of 5-HT6 receptors in memory processing and the interaction of glucocorticoids with the brain serotonergic system in modulating memory processing, we investigated whether the effect of glucocorticoids on the consolidation of emotionally arousing training depends on hippocampal 5-HT6 receptors.

Methods:

Rats were trained in an inhibitory avoidance task and immediately received the systemic injections of corticosterone (CORT) as well as the intra-hippocampal injections of 5-HT receptors agonist or antagonist. The memory retention test was done 48 hours after training and immediately after the behavioral test, the animals were sacrificed and the hippocampi (left and right) rapidly dissected out for molecular studies.

Results:

Post-training injections of different doses of CORT (1.25, 2.5, 5, and 10 mg/kg) enhanced memory retention in a dose-dependent manner. The CORT-induced enhancement of memory consolidation was blocked by bilateral intra-hippocampal injections of 5-HT6 receptor antagonist SB271046 (5 or 10 ng/per side), but not agonist EMD386088 (5 or 10 ng/per side). Furthermore, systemic CORT reduced 5-HT6 receptor mRNA and protein expression in the hippocampus. Both doses of 5-HT6 receptor agonist and antagonist significantly enhanced and reduced the expression of the 5-HT6 receptor, respectively, and both ligands at the higher dose (10 ng) enhanced memory consolidation. Moreover, CORT injection attenuated and enhanced, respectively, the effects of agonist and antagonist on 5-HT6 receptor expression.

Conclusion:

These behavioral and molecular findings indicated an interaction between glucocorticoids and hippocampal 5-HT6 receptors in the consolidation of emotionally arousing experiences.

Bombesin-induced enhancement of memory consolidation in male and female rat pups: Role of glutamatergic and dopaminergic systems

Previous studies have shown that the neuropeptide bombesin (BBS) enhances consolidation of specifically for inhibitory avoidance memory in adult rats. However, its effect on memory consolidation during premature period is not clear as well. Thus, this study evaluated the effect of BBS and its interaction with glutamatergic and dopaminergic systems on memory consolidation in rat pups. Male and female rat pups (30 days old) were trained in an inhibitory avoidance (IA) task (0.5 mA, 3 s footshock). Memory retention was tested 24 h later during which the latency to re-enter to the shock compartment was recorded. First, the effects of different doses (0.001, 0.0025, 0.005, 0.01 and 0.02 mg/kg) of BBS injected immediately following training were tested. Then, the effect of the most effective dose of BBS obtained in the previous experiment was examined in the presence of the glutamate NMDA receptor antagonist MK-801 (0.05 mg/kg), the dopamine D1 receptor antagonist SCH-23390 (0.05 mg/kg) and the dopamine D2 receptor antagonist sulpiride (20 mg/kg). Findings indicate that BBS significantly enhances memory consolidation at all tested doses in male pups and at a dose of 0.01 mg/kg in female pups. MK-801, SCH-23390 and sulpiride administration before BBS injection in individual groups significantly blocked BBS-induced memory enhancement. Our findings indicate that similar to adult rats, BBS enhances memory consolidation in developing rat. This enhancing effect is mediated, at least in part, via an interaction with glutamatergic and dopaminergic systems.

The effects of oral supplementation of spirulina platensis microalgae on hematological parameters in streptozotocin-induced diabetic rats

It is shown that diabetes can change hematological parameters and some microalgae, i.e. Spirulina platensis, could improve hematological parameters in non-diabetic rats. The purpose of this study was to investigate the effects of Spirulina platensis (SPM) microalgae on hematological parameters in diabetic rats induced by Streptozotocin. Rats, 2.5 males old, were grouped into two sections including healthy and diabetic and received orally 15 and 30 mg/kg body weight SPM for 5 weeks. Control rats received 0.3 ml of distilled water. The experimental groups were as follows; (SH15), healthy rats fed SPM (SH30) 30 mg/kg, diabetic rats fed 15 mg/kg SPM (SD15), diabetic rats fed SPM (SD30) 15 mg/kg, and diabetic control (DC). At the end of the test, blood samples were collected to measure red blood cells, white blood cells, mean corpuscular hemoglobin concentration (MCHC), mean cell volume (MCV) and packed cell volume (PCV). The induction of diabetes decreased RBC, MCHC, PCV, MCV and WBC (P < 0.05), but the oral supplement of SPM (30 mg/kg body weight) could improve RBC, WBC, MCHC, PCV and MCV in rats (P < 0.05). The oral complement of SPM, at high levels, seems to be an effective strategy against the negative effects of diabetes on hematological parameters.

Forced exercise attenuates neuropathic pain in chronic constriction injury of male rat: an investigation of oxidative stress and inflammation

BACKGROUND AND OBJECTIVE

Initial peripheral/central nerve injuries, such as chronic constriction injury (CCI)/spinal cord injury, are often compounded by secondary mechanisms, including inflammation and oxidative stress, which may lead to chronic neuropathic pain characterized by hyperalgesia or allodynia. On the other hand, exercise as a behavioral and non-pharmacological treatment has been shown to alleviate chronic neuropathic pain. Therefore, this study was conducted to examine whether or not exercise reduces neuropathic pain through modifying oxidative stress and inflammation in chronic constriction injury of the sciatic nerve.

MATERIALS AND METHODS

Wistar male rats weighing 200±20 g were randomly divided into five groups (normal, sham, CCI, pre-CCI exercise, and post-CCI exercise group). Sciatic nerve of anesthetized rats was loosely ligated to induce CCI, and they were then housed in separate cages. The rats ran on treadmill at a moderate speed for 3 weeks. Mechanical allodynia and thermal hyperalgesia were determined using von Frey filament and plantar test, respectively. Tumor necrosis factor-alpha (TNF-α) assayed in the cerebrospinal fluid, malondialdehyde, and total antioxidant capacity were measured in the serum using Western blot test, thiobarbituric acid, and ferric reducing ability of plasma (FRAP), respectively.

RESULTS

The mechanical allodynia (P=0.024) and thermal hyperalgesia (P=0.002) in the CCI group were higher than those in the sham group. Exercise after CCI reduced (P=0.004) mechanical allodynia and thermal hyperalgesia (P=0.025) compared with the CCI group. Moreover, the level of FRAP in the CCI group was (P=0.001) lower than that in the sham group, and post-CCI exercise reversed FRAP amount toward the control level (P=0.019). The amount of malondialdehyde did not differ between groups. Level of TNF-α increased in the CCI group (P=0.0002) compared with sham group and post-CCI exercise could reverse it toward the level of control (P=0.005).

CONCLUSION

Post CCI-exercise but not pre CCI-exercise reduces CCI-induced neuropathic pain. One of the possible involved mechanisms is increasing the total antioxidant capacity and reducing the amount of TNF-α.

Functional foods and their role in cancer prevention and health promotion: a comprehensive review

Following cardiovascular disease, cancer is the second leading cause of death in most affluent countries. The 13.3 million new cases of cancer in 2010 were predicted to cost US$ 290 billion, but the total costs were expected to increases to US$ 458 billion in the year 2030 on basis of World Economic Forum in 2011. More than half of all cancer cases and deaths worldwide are consider being preventable. From its inception, the disease control priorities series has focused attention on delivering efficacious health interventions that can result in dramatic reductions in mortality and disability at relatively modest cost. The approach has been multidisciplinary, and the recommendations have been evidence-based, scalable, and adaptable in multiple settings. Better and more equitable health care is the shared responsibility of governments and international agencies, public and private sectors, and societies and individuals, and all of these partners have been involved in the development of the series. Functional foods are foods and food components that supply health benefits beyond basic nutrition. It's-believed these functional foods do more than simply provide nutrients because they help to maintaining health and thereby reducing the risk of disease. There are some reported evidences showing association between functional foods and cancer. For example, S-ally cysteine of garlic and lycopene from tomatoes in combination form suppressed the development of chemically induced gastric cancer by modulation of apoptosis-associated proteins (reduced Bcl-2/Bax ratio and up-regulation of Bim and caspases 8 and 3) at considerably lower intakes than when these substances were given in isolation. Similarly, vitamin D3 with genistein in combination form precipitated a growth inhibition of prostate cancer cells at much lower concentration than when these substances were provided individually. There are very few studies conducted worldwide to see the effects of functional foods on health or cancer or related states. This review, presents the complex patterns of cancer incidence and death around the world and evidence on effective and cost-effective ways to control cancers. The evaluation of cancer will indicate where cancer treatment is ineffective and wasteful, and offer alternative cancer care packages that are cost-effective and suited to low-resource settings. In the present paper, cancer prevention by functional foods is reviewed and the possible mechanisms of action are described.

Data mining and medical world: breast cancers' diagnosis, treatment, prognosis and challenges

The amount of data in electronic and real world is constantly on the rise. Therefore, extracting useful knowledge from the total available data is very important and time consuming task. Data mining has various techniques for extracting valuable information or knowledge from data. These techniques are applicable for all data that are collected inall fields of science. Several research investigations are published about applications of data mining in various fields of sciences such as defense, banking, insurances, education, telecommunications, medicine and etc. This investigation attempts to provide a comprehensive survey about applications of data mining techniques in breast cancer diagnosis, treatment & prognosis till now. Further, the main challenges in these area is presented in this investigation. Since several research studies currently are going on in this issues, therefore, it is necessary to have a complete survey about all researches which are completed up to now, along with the results of those studies and important challenges which are currently exist in this area for helping young researchers and presenting to them the main problems that are still exist in this area.

The effects of different levels of peppermint alcoholic extract on body-weight gain and blood biochemical parameters of adult male Wistar rats

Introduction

Peppermint is an efficient medicinal plant for the treatment of diseases, and it also can be used to produce raw materials in the pharmaceutical industry. The purpose of the current study was to evaluate the effects of various levels of peppermint alcoholic extract on body-weight gain and blood biochemical parameters in adult male Wistar rats.

Methods

This experiment was conducted using a completely randomized design (CRD). Fifty adult, healthy, male Wistar rats (ages of 2.5–3 months; weights of 190–210 g) were allocated randomly into five groups. T1 was the control group in which the rats received 0.3 ml of distilled water). Groups T2, T3, T4, and T5 received 75, 150, 300, and 600 mg/kg of peppermint extract, respectively. The rats received daily pretreatment by oral gavages for 21 days. We recorded body weights at the beginning and at the end of the study to determine the changes in the body weights. Blood samples were collected for the measurement of glucose, cholesterol, triglycerides, HDL, LDL, albumin, globulin, and total protein. Statistical analysis of the data was done by SAS software. The data statistically analyzed using one-way analysis of variance (ANOVA), which was conducted through Dennett’s multiple comparison post-test.

Results

The results indicated that the rats treated with peppermint gained more weight (p < 0.05) and also decreased the serum concentrations of triglycerides, total cholesterol, LDL, and glucose in T3, T4 and T5 than the other groups (p < 0.05).

Conclusion

Peppermint extract had a positive effect on body-weight gain and some blood parameters in adult male Wistar rats. The findings showed that peppermint is a crucial substance at high temperature, and future research should be focused on determining the details of the mechanisms involved in producing the observed effects of peppermint extract.

Causes of Allergies and Diagnosis and Treatment

Allergies are diseases of the immune system that cause an overreaction to substances called "allergens." Allergies are grouped by the kind of trigger, time of year or where symptoms appear on the body: indoor and outdoor allergies (also called "hay fever," "seasonal," "perennial" or "nasal" allergies), food allergies, latex allergies, insect allergies, skin allergies and eye allergies. People who have allergies can live healthy and active lives. The search strategy has been devised on ovid medline and then adapted for the other databases (see Additional file 1 for full search strategies). In all cases the databases will be searched from 1 January 2000 to 30 September 2012, and limited to Europe based on the definition provided by the Organization for Economic Cooperation and Development (OECD).The resulting quality assessment scores are given alongside other study parameters in three tables. We assessed the systematic reviews based on the type of intervention or subject assessed for the prevention of food allergy or food sensitization. In this overview of systematic reviews concerning the etiology and prevention of food allergy, we identified 14 eligible publications. This systematic review will provide the most up to date estimates of the frequency of food allergy in Europe. Given the presumed increase in IgE mediated food allergy in the recent past, there is much interest in identifying the causes of food allergy and primary preventive strategies. These advances are creating the opportunities for novel therapies for food allergy. However, at the current time, the only treatment is avoidance.DOI: http://dx.doi.org/10.3126/ijls.v9i5.12701

The Effects of Different Levels Chlorell Microalgae on Performance and Immune Response of Laying Hens Under Heat Stress Condition

This study was conducted to determine the effects of different levels microalgae Chlorell sp. on performance of laying hens under heat stress condition. A completely randomized design experiment, with 7 replicates and 6 treatments (9 birds per replicate) was carried out by allotting 378 white Lohman strain laying hens at 65 weeks of age. Six experimental treatments were continual addition of 0, 100, 200, 300,400 ppm microalgae Chlorell and 400 ppm toein to drinking warer were fed to laying hens for 9 weeks. Egg production, egg weight, egg mass output and feed intake were determined. Antibody production against sheep red blood cells (SRBC) also was measured. Data  were  analyzed  by  ANOVA  using  General  Linear Models procedure of  SAS software and comparison of means  were  compared  using  Duncan’s  multiple  range test. The results of this experiment showed that microalgae Chlorell had no effect on productive performance. Adding microalgae Chlorell to the drinking water improved immune response of laying hens and a more positive effect was observed when 400 ppm added to the water. It is concluded that the addition of microalgae Chlorell to the water drinking of laying hens improved immune response of laying hens.DOI: http://dx.doi.org/10.3126/ijls.v9i2.12058 International Journal of Life Sciences 9 (2) : 2015; 71-74

The relationship between progesterone and biochemical constituents of amniotic fluid with placenta traits in Iranian crossbred ewes (Arkhar-Merino×Ghezel)

OBJECTIVE

To determine the values of amniotic fluid (AF) progesterone and biochemical constituents and its associated placenta traits in Iranian crossbred ewes (Arkhar-Merino×Ghezel).

METHODS

Sixty ewes (2-5 years old, weighing 40-50 kg) were treated with controlled internal drug release induced 30 mg progesterone for 14 d and were injected with 400 IU pregnant mare serum gonadotropin at the time of CIDR withdrawal. After the detection of estrus, ewes were hand-mated. After expelling of each fetus accompanied by fetal membranes, 10 mL AF was taken from fetal sac for spectrophotometer methods (glucose, urea, creatinine, total protein, cholesterol, triglycerides, calcium and phosphorus) and radioimmunoassay (progesterone) analysis.

RESULTS

Results indicated that there were highly positive correlations between placental efficiency and cotyledon density (r=0.764, P<0.01), and negative correlation between placental weight (PW) with the total volume amniotic fluid (TVAF) (r=-0.872, P<0.01). A positive relationship was calculated between TVAF with total protein and creatinine (r=0.418, P<0.01 and r=0.639, P<0.05, respectively). However, the correlation between the glucose and PW, cotyledon length and calcium were significantly positive (r=0.704 and r=0.712; P<0.01, respectively). The findings of this study demonstrated that there were no relationships between progesterone concentrations and placental traits (P>0.01), except for PW (r=0.665).

CONCLUSIONS

In conclusion, the significant correlation between the AF biochemical and progesterone with placental traits for the above-mentioned metabolites suggests that metabolic changes in AF levels will reflect the condition in the AF.

The influence of the corpus luteum on metabolites composition of follicular fluid from different sized follicles and their relationship to serum concentrations in dairy cows

The presence of corpus luteum may have a local effect on metabolite composition of follicular fluid (FF) and could indirectly influence follicular development and oocyte quality. The purpose of this study was to examine the influence of the corpus luteum on metabolite composition of follicular fluid (FF), harvested from different-sized follicles and the relationship between metabolite composition of FF to blood serum in dairy cows. Ovaries and blood samples were collected from 30 female adult Holstein Friesian cows, 4-7 years old, with clinically normal reproductive tracts. The animals were in the diestrus stage and selected post mortem. The ovaries collected were classified based on the presence and absence of corpus luteum (CL(+/-)). Visible follicles on the surface of the ovaries were classified into (i) small (3-5mm), (ii) medium (6-9 mm) and (iii) large (10-20mm) based on their diameter. Follicular fluid was aspirated from follicles with different sizes in CL(+) and CL(-) ovaries. Blood and FF samples were analyzed for various biochemical constituents including glucose, cholesterol, triglyceride, total protein, albumin and globulin. The results showed that serum concentration of glucose, cholesterol and triglyceride was significantly different (p≤0.05) in FF from follicles of different size categories. Differences between various follicle size categories in CL(-) ovaries were only significant for concentrations of glucose, cholesterol and triglyceride. FF concentration of glucose and cholesterol in the same follicle size categories in CL(+) ovaries was significantly lower than that of CL(-) ovaries. These results indicate that levels of the biochemical metabolites in serum and FF differ significantly. In addition, FF concentrations of biochemical metabolites were related to follicular size and to the presence or absence of corpus luteum.