The effect of orexin-A on motor and cognitive functions in a rat model of Parkinson's disease.

OBJECTIVE:  The aim of this study was to evaluate the effect of orexin-A (OX-A) and the orexin-1 receptor antagonist SB-334867 (SB) on motor and cognitive functions in a rat model of Parkinson's disease. METHODS: Parkinson was induced by intracerebroventricular (i.c.v) injection of 6- hydroxydopamine (6-OHDA) (200 µg/rat). 72 h later, the treatment was initiated by i.c.v administration of SB (30 nmol/rat) and/or OX-A (0.3 nmol/rat) for 10 days. Motor functions were monitored using rotarod and hanging tests. Cognitive function was assessed by passive avoidance test (Shuttle box). Results: OX-A administration in 6-OHDA treated rats remarkably increased the time which animals run on rod (in rotarod test) and also the latency to fall (in hanging test) (P < 0.01 and P < 0.001, respectively). Conversely, administration of SB in 6-OHDA-treated rats decreased the mentioned indices (P < 0.05 for latency to fall). Administration of agonist and/or antagonist of orexin-1 receptors had no significant effect on 6-OHDA induced cognitive impairment in rats. CONCLUSION:  Results of this study suggest that the orexinergic system might be involved in sensory-motor deficits of Parkinson's disease.

Tactile learning in rodents: Neurobiology and neuropharmacology.

Animal models of learning and memory have been the subject of considerable research. Rodents such as mice and rats are nocturnal animals with poor vision, and their survival depends on their sense of touch. Recent reports have shown that whisker somatosensation is the main channel through which rodents collect and process environmental information. This review describes tactile learning in rodents from a neurobiological and neuropharmacological perspective, and how this is involved in memory-related processes.

Levels of Transforming Growth Factor-Beta After Immunization of Mice With in vivo prepared Toxoplasma gondii Excretory/Secretory Proteins.

BACKGROUND: Zoonotic parasite Toxoplasma gondii has a high prevalence in human populations. A suitable vaccine for animals can stop the transmission of infection between animal and human. OBJECTIVES: The aim of this study was to evaluate in vivo prepared excretory/secretory antigens (E/SA) as a potential candidate for immunization against the parasite and its effect on the production of transforming growth factor-beta (TGF-ß). MATERIALS AND METHODS: Toxoplasma gondii tachyzoites were inoculated in the peritoneal cavity of mice and E/SA was harvested and used in animal immunization with and without adjuvant. Serum levels of anti-E/SA antibodies and TGF-ß were measured in days 0, 3, 7, 14, 28 and 56 after immunization using ELISA technique. The measurements were statistically analyzed. RESULTS: Our results showed that the serum levels of anti-E/SA immunoglobulins significantly increased in all of the immunized groups. The differences of the serum levels of TGF-ß between the groups were statistically significant at days 28 and 56 after immunization with E/SA. CONCLUSIONS: Based on our study, in vivo prepared E/SA may be considered as a good candidate for animal immunization.

Effect of aqueous extract of Achillea millefolium on the development of experimental autoimmune encephalomyelitis in C57BL/6 mice.

OBJECTIVE: Achillea millefolium (A. millefolium) is widely used as an anti-inflammatory remedy in traditional and herbal medicine. In this study, we investigated the effect of an aqueous extract from A. millefolium on experimental autoimmune encephalomyelitis (EAE) and on the serum cytokine levels in C57BL/6 mice. MATERIALS AND METHODS: EAE was induced in 63 C57BL/6 mice weighing 20-25 g (8 weeks old). Following immunization, the treatment protocol was initiated by using different doses of an aqueous extract from A. millefolium (1, 5, and 10 mg/mouse/day). Histopathologic assessments were performed by hematoxylin and eosin (H and E) and luxol fast blue (LFB) staining. Behavioral disabilities were recorded by a camera. Serum levels of interleukin (IL)-10, IL-12, and transforming growth factor (TGF)-ß were measured using enzyme-linked immunosorbent assay (ELISA). RESULTS: On average, mice developed classical behavioral disabilities of EAE, 13.2 ± 1.9 days following immunization. Treatment of mice with A. millefolium led to delay the appearance of behavioral disabilities along with reduced severity of the behavioral disabilities. Treatment with A. millefolium prevented weight loss and increased serum levels of TGF-ß in immunized mice with MOG35-55. EAE-induced mice, which were treated with A. millefolium, had less cerebral infiltration of inflammatory cells. CONCLUSION: The results demonstrated that treatment with aqueous extract of A. millefolium may attenuate disease severity, inflammatory responses, and demyelinating lesions in EAE-induced mice. In addition, following treatment with A. millefolium, serum levels of TGF-ßwere increased in EAE-induced mice.

Interleukin-10 Serum Levels after Vaccination with In Vivo Prepared Toxoplasma gondii Excreted/Secreted Antigens.

OBJECTIVES: Toxoplasma gondii is a worldwide prevalent zoonotic parasite which causes toxoplasmosis. An appropriate vaccine for animals could interrupt the circle between animals and humans. Our previous study showed that excreted/secreted antigens (E/SA), derived from the peritoneum of mice infected with T. gondii tachyzoites could be considered as a good candidate for animal vaccination. Interleukin-10 (IL-10) inhibits proliferation of B and T lymphocytes and induces homeostasis in immune system responses. However, since IL-10 has also been shown to suppress the killing of T. gondii by human macrophages, the aim of this study was to evaluate IL-10 serum levels after vaccination with T. gondii E/SA prepared in vivo. METHODS: T. gondii tachyzoites were inoculated in the peritoneum of mice and harvested E/SA were used as a vaccine, with and without adjuvant, in T. gondii infected and un-infected mice. IL-10 serum levels were evaluated using the ELISA technique. RESULTS: The data showed that although serum levels of IL-10 were not changed at the early phases, they were elevated at the end phases of vaccination with T. gondii E/SA. CONCLUSION: Based on these and our previous results, it can be concluded that in vivo prepared T. gondii E/SA could be considered as a good candidate for animal vaccination.