Parkinson’s disease (PD) is one of the common long-term degenerative disorders that primarily affect motor systems. Gastrointestinal (GI) symptoms are common in individuals with PD and often present before motor symptoms. It has been found that gut dysbiosis to PD pathology is related to the severity of motor and non-motor symptoms in PD. Probiotics have been reported to have the ability to improve the symptoms related to constipation in PD patients. However, the evidence from preclinical or clinical research to verify the beneficial effects of probiotics for the motor functions in PD is still limited. An experimental PD animal model could be helpful in exploring the potential therapeutic strategy using probiotics. In the current study, we examined whether daily and long-term administration of probiotics has neuroprotective effects on nigrostriatal dopamine neurons and whether it can further alleviate the motor dysfunctions in PD mice. Transgenic MitoPark PD mice were chosen for this study and the effects of daily probiotic treatment on gait, beam balance, motor coordination, and the degeneration levels of dopaminergic neurons were identified. From the results, compared with the sham treatment group, we found that the daily administration of probiotics significantly reduced the motor impairments in gait pattern, balance function, and motor coordination. Immunohistochemically, a tyrosine hydroxylase (TH)-positive cell in the substantia nigra was significantly preserved in the probiotic-treated PD mice. These results showed that long-term administration of probiotics has neuroprotective effects on dopamine neurons and further attenuates the deterioration of motor dysfunctions in MitoPark PD mice. Our data further highlighted the promising possibility of the potential use of probiotics, which could be the relevant approach for further application on human PD subjects.

A new measure of cortical inhibition by mechanomyography and paired-pulse transcranial magnetic stimulation in unanesthetized rats. J Neurophysiol 107: 966 -972, 2012. First published October 19, 2011 doi:10.1152/jn.00690.2011.-Paired-pulse transcranial magnetic stimulation (ppTMS) is a safe and noninvasive tool for measuring cortical inhibition in humans, particularly in patients with disorders of cortical inhibition such as epilepsy. However, ppTMS protocols in rodent disease models, where mechanistic insight into the ppTMS physiology and into disease processes may be obtained, have been limited due to the requirement for anesthesia and needle electromyography. To eliminate the confounding factor of anesthesia and to approximate human ppTMS protocols in awake rats, we adapted the mechanomyogram (MMG) method to investigate the ppTMS inhibitory phenomenon in awake rats and then applied differential pharmacology to test the hypothesis that long-interval cortical inhibition is mediated by the GABA A receptor. Bilateral hindlimbevoked MMGs were elicited in awake rats by long-interval ppTMS protocols with 50-, 100-, and 200-ms interstimulus intervals. Acute changes in ppTMS-MMG were measured before and after intraperitoneal injections of saline, the GABA A agonist pentobarbital (PB), and GABA A antagonist pentylenetetrazole (PTZ). An evoked MMG was obtained in 100% of animals by single-pulse stimulation, and ppTMS resulted in predictable inhibition of the test-evoked MMG. With increasing TMS intensity, MMG amplitudes increased in proportion to machine output to produce reliable input-output curves. Simultaneous recordings of electromyography and MMG showed a predictable latency discrepancy between the motor-evoked potential and the evoked MMG (7.55 Ϯ 0.08 and 9.16 Ϯ 0.14 ms, respectively). With pharmacological testing, time course observations showed that ppTMS-MMG inhibition was acutely reduced following PTZ (P Ͻ 0.05), acutely enhanced after PB (P Ͻ 0.01) injection, and then recovered to pretreatment baseline after 1 h. Our data support the application of the ppTMS-MMG technique for measuring the cortical excitability in awake rats and provide the evidence that GABA A receptor contributes to long-interval paired-pulse cortical inhibition. Thus ppTMS-MMG appears a well-tolerated biomarker for measuring GABA A -mediated cortical inhibition in rats.long-interval intracortical inhibition; mechanomyogram; GABA TRANSCRANIAL MAGNETIC STIMULATION (TMS) is a well-tolerated technique for measuring regional cortical excitability that is gaining acceptance as a means to examine cortical physiology in healthy human subjects and in patients with neurological disorders such as epilepsy, stroke, and mild concussion (Manganotti et al. 2001(Manganotti et al. , 2008Tremblay et al. 2011;Valzania et al. 1999). In TMS, the cortex is activated by a powerful fluctuating extracranial magnetic field, which induces small intracranial electrical currents (reviewed in Kobayashi and PascualLeone 2003). In humans, TMS can be applied to the moto...

Traumatic brain injury (TBI) is a major cause of death and disability worldwide. Neuronal apoptosis in the hippocampus has been detected after TBI. The hippocampal dysfunction may result in cognitive deficits in learning, memory, and spatial information processing. Our previous studies demonstrated that a p53 inhibitor, pifithrin-α oxygen analogue (PFT-α (O)), significantly reduced cortical cell death, which is substantial following controlled cortical impact (CCI) TBI, and improved neurological functional outcomes via anti-apoptotic mechanisms. In the present study, we examined the effect of PFT-α (O) on CCI TBI-induced hippocampal cellular pathophysiology in light of this brain region’s role in memory. To investigate whether p53-dependent apoptosis plays a role in hippocampal neuronal loss and associated cognitive deficits and to define underlying mechanisms, SD rats were subjected to experimental CCI TBI followed by the administration of PFT-α or PFT-α (O) (2 mg/kg, i.v.) or vehicle at 5 h after TBI. Magnetic resonance imaging (MRI) scans were acquired at 24 h and 7 days post-injury to assess evolving structural hippocampal damage. Fluoro-Jade C was used to stain hippocampal sub-regions, including CA1 and dentate gyrus (DG), for cellular degeneration. Neurological functions, including motor and recognition memory, were assessed by behavioral tests at 7 days post injury. p53, p53 upregulated modulator of apoptosis (PUMA), 4-hydroxynonenal (4-HNE), cyclooxygenase-IV (COX IV), annexin V and NeuN were visualized by double immunofluorescence staining with cell-specific markers. Levels of mRNA encoding for caspase-3, p53, PUMA, Bcl-2, Bcl-2-associated X protein (BAX) and superoxide dismutase (SOD) were measured by RT-qPCR. Our results showed that post-injury administration of PFT-α and, particularly, PFT-α (O) at 5 h dramatically reduced injury volumes in the ipsilateral hippocampus, improved motor outcomes, and ameliorated cognitive deficits at 7 days after TBI, as evaluated by novel object recognition and open-field test. PFT-α and especially PFT-α (O) significantly reduced the number of FJC-positive cells in hippocampus CA1 and DG subregions, versus vehicle treatment, and significantly decreased caspase-3 and PUMA mRNA expression. PFT-α (O), but not PFT-α, treatment significantly lowered p53 and elevated SOD2 mRNA expression. Double immunofluorescence staining demonstrated that PFT-α (O) treatment decreased p53, annexin V and 4-HNE positive neurons in the hippocampal CA1 region. Furthermore, PUMA co-localization with the mitochondrial maker COX IV, and the upregulation of PUMA were inhibited by PFT-α (O) after TBI. Our data suggest that PFT-α and especially PFT-α (O) significantly reduce hippocampal neuronal degeneration, and ameliorate neurological and cognitive deficits in vivo via antiapoptotic and antioxidative properties.

Gait disturbances are common in the rat model of Parkinson's disease (PD) by administrating 6-hydroxydopamine. However, few studies have simultaneously assessed spatiotemporal gait indices and the kinematic information of PD rats during overground locomotion. This study utilized a simple, accurate, and reproducible method for quantifying the spatiotemporal and kinematic changes of gait patterns in hemiparkinsonian rats. A transparent walkway with a tilted mirror was set to capture underview footprints and lateral joint ankle images using a high-speed and high-resolution digital camera. The footprint images were semi-automatically processed with a threshold setting to identify the boundaries of soles and the critical points of each hindlimb for deriving the spatiotemporal and kinematic indices of gait. Following PD lesion, asymmetrical gait patterns including a significant decrease in the step/stride length and increases in the base of support and ankle joint angle were found. The increased footprint length, toe spread, and intermediary toe spread were found, indicating a compensatory gait pattern for impaired locomotor function. The temporal indices showed a significant decrease in the walking speed with increased durations of the stance/swing phase and double support time, which was more evident in the affected hindlimb. Furthermore, the ankle kinematic data showed that the joint angle decreased at the toe contact stage. We conclude that the proposed gait analysis method can be used to precisely detect locomotor function changes in PD rats, which is useful for objective assessments of investigating novel treatments for PD animal model.

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The accumulation of reactive oxygen species (ROS) have implicated the pathogenesis of several human diseases including neurodegenerative disorders, stroke, and traumatic brain injury, hence protecting neurons against ROS is very important. In this study, we focused on sigma-1 receptor (Sig-1R), a chaperone at endoplasmic reticulum, and investigated its protective functions. Using hydrogen peroxide (H2O2)-induced ROS accumulation model, we verified that apoptosis-signaling pathways were elicited by H2O2 treatment. However, the Sig-1R agonists, dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEAS), reduced the activation of apoptotic pathways significantly. By performing protein-protein interaction assays and shRNA knockdown of Sig-1R, we identified the brain Zinc finger protein 179 (Znf179) as a downstream target of Sig-1R regulation. The neuroprotective effect of Znf179 overexpression was similar to that of DHEAS treatment, and likely mediated by affecting the levels of antioxidant enzymes. We also quantified the levels of peroxiredoxin 3 (Prx3) and superoxide dismutase 2 (SOD2) in the hippocampi of wild-type and Znf179 knockout mice, and found both enzymes to be reduced in the knockout versus the wild-type mice. In summary, these results reveal that Znf179 plays a novel role in neuroprotection, and Sig-1R agonists may be therapeutic candidates to prevent ROS-induced damage in neurodegenerative and neurotraumatic diseases.

The aim of this study was to explore the potential for a better recovery outcome for the Achilles tendon at an early healing stage when a mixed biomaterial-tenocyte injection is used. The experimental animals underwent single limb Achilles tendon transection followed by suturing repair. A solution of either hyaluronic acid with or without tenocytes or normal saline was randomly chosen to be injected around the injury site after surgery. To obtain the comprehensive recovery condition of the rats on different management protocols, the animals were evaluated histologically, mechanically, and functionally. A significant difference in the recovery condition was found in the injured tendon injected with the hyaluronic acid solution with tenocytes compared with the other groups. Tendon stiffness and the locomotion abilities of the rats with healing Achilles tendons were improved in the hyaluronic acid with tenocyte transplantation group. The acceleration of the inflammatory phase in rats with the hyaluronic acid with tenocyte injections might be the major reason for the better functional outcomes.

Background: Transcranial direct current stimulation (tDCS) has been proven to be able to modulate motor cortical plasticity might have potential as an alternative, adjunctive therapy for Parkinson's disease (PD). However, the efficacy of tDCS in PD is still uncertain. A disease animal model may be useful to clarify the existence of a treatment effect and to explore an effective therapeutic strategy using tDCS protocols.Objective: The current study was designed to identify the comprehensive therapeutic effects of tDCS in 6-hydroxydopamine (6-OHDA)-lesioned PD rats.Methods: Following early and long-term tDCS application (starting 24 h after PD lesion, 300 mA anodal tDCS, 20 min/day, 5 days/week) in awake PD animals for a total of 4 weeks, the effects of tDCS on motor and non-motor behaviors as well as dopaminergic neuron degeneration levels, were identified. Results: We found that the 4-week tDCS intervention significantly alleviated 6-OHDA-induced motor deficits in locomotor activity, akinesia, gait pattern and anxiety-like behavior, but not in apomorphineinduced rotations, recognition memory and depression-like behavior. Immunohistochemically, tyrosine hydroxylase (TH)-positive neurons in the substantia nigra were significantly preserved in the tDCS intervention group. Conclusions: These results suggest that early and long-term tDCS could exert neuroprotective effects and reduce the aggravation of motor dysfunctions in a 6-OHDA-induced PD rat model. Furthermore, this preclinical model may enhance the promising possibility of the potential use of tDCS and serve as a