The effect of olibanum on the rats with memory deficit induced by scopolamine.

BACKGROUND: Oxidative stress is an important contributor to Alzheimer's disease. Olibanum has therapeutic effects on various diseases. The effect of Olibanum on memory deficit induced by scopolamine (Sco) was challenged. METHODS: Four groups were considered as (1) control (2) Sco, (3-4) Sco - Olib 100 and 200 mg/kg. Treatment by Olib or vehicle was done for two weeks. The third week was accompanied by the Morris water maze (MWM) and passive avoidance (PA) with Sco injection. On the last day, the brain and hippocampus were used for evaluation of the malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), and a total thiol group. RESULTS: Sco increased the traveled time and distance to reach the hidden platform during five days of learning (p<0.01 - p<0.001) whereas it decreased the traveled time and distance (p<0.05- p<0.01) in the target area during the probe test of MWM. Sco also decreased delay time in the PA test (P<0.05 - P<0.001). Sco also decreased CAT, SOD, and thiol, whereas it, increased MDA in both the cortex and hippocampus (p<0.01 - p<0.001). Olib attenuated the impaired performance of the rats induced by Sco in MWM and PA tests. Olib reversed the increasing effects of Sco on MDA in both cortex and hippocampus and also reversed the attenuating effects of Sco on CAT, SOD, and thiol. CONCLUSION: Olib had an inhibitory effect on memory deficit induced by Sco probably through its anti-oxidant property.

Grape seed extract effects on hippocampal neurogenesis, synaptogenesis and dark neurons production in old mice. Can this extract improve learning and memory in aged animals?

BACKGROUND: During the elderly, hippocampal neurogenesis and synaptogenesis reduce and dark neurons (DNs) increase, leading to cognitive impairment. It is believed that natural products can protect the neural cells and system by protecting from damages or promoting regeneration. Therefore, the effects of grape seed extract (GSE) on the hippocampus of aged mice were investigated in this study. METHODS: twelve old mice were divided into two groups of control and GSE. Animals in the GSE group received 300 mg/kg of GSE for eight weeks via gavage. At the end of treatment, cognition performance was evaluated by Morris water maze (MWM) and passive avoidance tests. Hippocampal neurogenesis, synaptogenesis and DNs production were evaluated with immunohistochemistry and histological evaluations on 5-micron coronal tissue sections. RESULTS: The hippocampal mean number of double cortin positive cells (DCX+) per unit area, as well as synaptophysin expression in the GSE group, were significantly higher than the control group (p < 0.01). The frequency of DNs in the GSE group was lower than the control group (p < 0.05). Behavioral tests showed that GSE improves memory and learning performance. CONCLUSION: Consuming GSE in the elderly can potentially alleviate the age-related reduction of hippocampal neurogenesis and synaptogenesis. It is also able to decrease hippocampal DNs production and increase memory and learning.

Neuroprotective effects of garlic extract on dopaminergic neurons of substantia nigra in a rat model of Parkinson's disease: motor and non-motor outcomes.

Parkinson's disease (PD) is a common and severe neurodegenerative disorder associated with a selective loss of dopaminergic neurons in substantia nigra pars compacta. The crucial role of oxidative stress and inflammation in PD onset and progression is evident. It has been proven that garlic extract (GE) protects the cells from oxidative stress, inflammation, mitochondrial dysfunction and apoptosis. That is, we aimed to investigate if GE reveals protective features on the preclinical model of PD. The study has been designed to evaluate both preventive (GE administered before 6-OHDA injection) and therapeutic (GE administered after 6-OHDA injection) effects of GE on the animal model. Forty male Wistar rats were divided into 4 groups including control, lesion, treatment I (received GE before 6-OHDA injection) and treatment II (received GE both before and after 6-OHDA injection). At the end of treatment, hanging, rotarod, open field and passive avoidance tests as well as immunohistochemistry were performed to evaluate the neuroprotective effects of garlic against PD. Our immunohistochemistry analysis revealed that the tyrosine hydroxylase positive cells (TH+) in GE treated groups were significantly higher (p˂0.001) than the lesion group. The motor deficiency significantly improved in hanging, rotarod, open-field and apomorphine-induced rotational tests. We observed an attenuation in memory impairment induced by PD on GE treated group. Therefore, we found that GE protects dopaminergic neurons in 6-OHDA-induced neurotoxicity and ameliorates movement disorders and behavioral deficits.