Vitamin D (VD3) Intensifies the Effects of Exercise and Prevents Alterations of Behavior, Brain Oxidative Stress, and Neuroinflammation, in Hemiparkinsonian Rats.

In the present study, we investigated the effects of physical exercise in the presence of Vitamin D3 (VD3), on 6-hydroxydopamine (6-OHDA)-lesioned hemiparkinsonian rats. The animals were divided into sham-operated (SO), 6-OHDA-lesioned, and 6-OHDA-lesioned plus VD3 (1 µg/kg, 21 days), in the absence (no exercise, NE) and presence (with exercise, WE) of physical exercise on a treadmill (30 min, speed of 20 cm/s, once a day/21 days). This procedure started, 24 h after the stereotaxic surgery (injections of 6-OHDA into the right striatum). The animals were then subjected to behavioral (rotarod, open field, and apomorphine tests) and their brain areas were dissected for neurochemical, dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC) determinations, and immunohistochemical studies for tyrosine hydroxylase (TH), dopamine transporter (DAT), and vitamin D receptor (VD3R). The effects on the brain oxidative stress: nitrite/nitrate, glutathione (GSH), and malondialdehyde (MDA) measurements were also evaluated. Behavioral changes of the 6-OHDA lesioned group were improved by exercise plus VD3. Similar results were observed in dopamine (DA) and 3,4-dihydroxyphenylacetic acid (DOPAC) concentrations increased by exercise and VD3, compared with SO groups. Additionally, tyrosine hydroxylase (TH) and dopamine transporter (DAT) immunoexpressions were decreased in the 6-OHDA-lesioned groups, with values normalized after exercise and VD3. The VD3 receptor immunoexpression decreased in the 6-OHDA (NE) group, and this was attenuated by exercise, especially after VD3. While 6-OHDA lesions increased, VD3 supplementation decreased the oxidative stress, which was intensified by exercise. VD3 showed neuroprotective properties that were intensified by physical exercise. These VD3 actions on hemiparkinsonian rats are possibly related to its antioxidant and anti-inflammatory effects.

Rats recognize spatial and temporal attributes in a new object recognition memory task with multiple trials.

BACKGROUND: Episodic-like memory tasks based on the spontaneous exploration of objects are commonly applied in one-trial protocols. However, multiple-trial designs are known to reduce animal numbers and data variance, providing faster accumulation of data. NEW METHOD: In this study, we devised a new object recognition memory task for rats that carry out multiple trials per session. We developed three types of continual trial tasks: a longer protocol, a shorter protocol, and a protocol in which the experimental session was divided into two days. RESULTS: In our design, rats expressed temporal and spatial memory, but not what-where-when content integration. We found that shorter protocols were more efficient to evaluate memory capabilities. COMPARISON WITH EXISTING METHODS: To the best of our knowledge, it is the first object recognition task with multiple trials that simultaneously assess the temporal and spatial aspects of episodic-like memory. CONCLUSIONS: We suggest that our task is suitable for the simultaneous measurements of brain functions related to spatial and temporal attributes in rats.

L-linalool exerts a neuroprotective action on hemiparkinsonian rats.

Linalool (LIN) is a monoterpene, responsible for the aroma of essential oils in some species. It presents a sedative and anxiolytic potential, enhancing GABAergic currents and behaving as a benzodiazepine-type of drug. The objectives of the present work were to study the neuroprotective effects of LIN on a model of Parkinson's disease. For that, male Wistar rats were divided into the following groups: sham-operated (SO), 6-OHDA-lesioned, and 6-OHDA-lesioned and treated with LIN (25, 50, and 100 mg/kg, p.o.) for 2 weeks. Afterwards, the animals were subjected to behavioral tests (apomorphine-induced rotations, open field, and forced swimming tests). Then, the animals were euthanized, and the striatum, hippocampus, and prefrontal cortex were processed for neurochemistry (nitrite and lipoperoxidation measurements) and immunohistochemistry (TH and DAT) assays. The results were analyzed by ANOVA and Tukey's test for multiple comparisons and considered significant at p < 0.05. LIN significantly improved the behavioral alterations of the 6-OHDA-lesioned group, as evaluated by the apomorphine-induced rotations, open field, and forced swimming tests. In addition, LIN partially reversed the decreased DA, DOPAC, and HVA contents observed in the 6-OHDA-lesioned striatum. The untreated 6-OHDA group presented increased nitrite contents and lipoperoxidation in all the brain areas studied, and these changes were completely reversed after LIN treatments. Finally, LIN significantly prevented the reduction in TH and DAT expressions demonstrated in the right 6-OHDA-lesioned striatum. All these data strongly suggest that LIN presents a neuroprotective action in hemiparkinsonian rats, probably related to the drug anti-inflammatory and antioxidant activities.

Corrigendum to "The Treadmill Exercise Protects against Dopaminergic Neuron Loss and Brain Oxidative Stress in Parkinsonian Rats".

[This corrects the article DOI: 10.1155/2017/2138169.].

The Treadmill Exercise Protects against Dopaminergic Neuron Loss and Brain Oxidative Stress in Parkinsonian Rats.

Parkinson's disease (PD), a progressive neurological pathology, presents motor and nonmotor impairments. The objectives were to support data on exercise benefits to PD. Male Wistar rats were distributed into sham-operated (SO) and 6-OHDA-lesioned, both groups without and with exercise. The animals were subjected to treadmill exercises (14 days), 24 h after the stereotaxic surgery and striatal 6-OHDA injection. Those from no-exercise groups stayed on the treadmill for the same period and, afterwards, were subjected to behavioral tests and euthanized for neurochemical and immunohistochemical assays. The data, analyzed by ANOVA and Tukey post hoc test, were considered significant for p < 0.05. The results showed behavioral change improvements in the 6-OHDA group, after the treadmill exercise, evaluated by apomorphine rotational behavior, open field, and rota rod tests. The exercise reduced striatal dopaminergic neuronal loss and decreased the oxidative stress. In addition, significant increases in BDNF contents and in immunoreactive cells to TH and DAT were also observed, in striata of the 6-OHDA group with exercise, relatively to those with no exercise. We conclude that exercise improves behavior and dopaminergic neurotransmission in 6-OHDA-lesioned animals. The increased oxidative stress and decreased BDNF contents were also reversed, emphasizing the importance of exercise for the PD management.