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Background High-frequency transcutaneous neuromuscular electrical nerve stimulation (TENS) is currently used for the administration of electrical current in denervated muscle to alleviate muscle atrophy and enhance motor function; however, the time window (i.e. either immediate or delayed) for achieving benefit is still undetermined. In this study, we conducted an intervention of sciatic nerve crush injury using high-frequency TENS at different time points to assess the effect of motor and sensory functional recovery. Results Animals with left sciatic nerve crush injury received TENS treatment starting immediately after injury or 1 week later at a high frequency(100 Hz) or at a low frequency (2 Hz) as a control. In SFI gait analysis, either immediate or late admission of high-frequency electrical stimulation exerted significant improvement compared to either immediate or late administration of low-frequency electrical stimulation. In an assessment of allodynia, immediate high frequency electrical stimulation caused a significantly decreased pain threshold compared to late high-frequency or low-frequency stimulation at immediate or late time points. Immunohistochemistry staining and western blot analysis of S-100 and NF-200 demonstrated that both immediate and late high frequency electrical stimulation showed a similar effect; however the effect was superior to that achieved with low frequency stimulation. Immediate high frequency electrical stimulation resulted in significant expression of TNF-α and synaptophysin in the dorsal root ganglion, somatosensory cortex, and hippocampus compared to late electrical stimulation, and this trend paralleled the observed effect on somatosensory evoked potential. The CatWalk gait analysis also showed that immediate electrical stimulation led to a significantly high regularity index. In primary dorsal root ganglion cells culture, high-frequency electrical stimulation also exerted a significant increase in expression of TNF-α, synaptophysin, and NGF in accordance with the in vivo results. Conclusion Immediate or late transcutaneous high-frequency electrical stimulation exhibited the potential to stimulate the motor nerve regeneration. However, immediate electrical stimulation had a predilection to develop neuropathic pain. A delay in TENS initiation appears to be a reasonable approach for nerve repair and provides the appropriate time profile for its clinical application. Electronic supplementary material The online version of this article (10.1186/s12868-018-0437-9) contains supplementary material, which is available to authorized users.

Background Magnesium supplementation has potential for use in nerve regeneration. The expression of some magnesium transporter genes is reflective of the intracellular magnesium levels. Objective To assess the expression of various magnesium transporter genes as they relate to neurological alterations in a sciatic nerve injury model. Methods Sciatic nerve injury was induced in rats, which were then fed either basal or high magnesium diets. Magnesium concentrations and 5 magnesium transporter genes (SLC41A1, MAGT1, CNNM2, TRPM6, and TRPM7) were measured in the tissue samples. Results The high magnesium diet attenuated cytoskeletal loss in a dose-dependent manner in isolated nerve explants. The high magnesium diet augmented nerve regeneration and led to the restoration of nerve structure, increased S-100, and neurofilaments. This increased regeneration was consistent with the improvement of neurobehavioral and electrophysiological assessment. The denervated muscle morphology was restored with the high magnesium diet, and that was also highly correlated with the increased expression of desmin and acetylcholine receptors in denervated muscle. The plasma magnesium levels were significantly elevated after the animals consumed a high magnesium diet and were reciprocally related to the down-regulation of CNNM2, MagT1, and SCL41A1 in the blood monocytes, nerves, and muscle tissues of the nerve crush injury model. Conclusion The increased plasma magnesium levels after consuming a high magnesium diet were highly correlated with the down-regulation of magnesium transporter genes in monocytes, nerves, and muscle tissues after sciatic nerve crush injury. The study findings suggest that there are beneficial effects of administering magnesium after a nerve injury.

Purpose Parkinson's disease (PD) is a progressive degenerative central nervous system disorder that particularly impairs motor function. As PD advances, gait disorders become more pronounced and are often difficult to treat with current pharmacological therapies. Physical activity improves both mobility in and the daily living activities of patients with PD. Mitochondrial alterations and oxidative stress contribute to PD progression. Therefore, the association between mitochondria and exercise in PD and the implicated regulation of mitochondrial proteins was explored in this study. Methods In this study, we developed a unilateral 6-hydroxydopamine rat model of PD and executed 4 weeks of treadmill training. Motor behavior was evaluated through gait change analysis (the CatWalk method) and rotational testing. The viability of dopaminergic neurons, mitochondrial function, and oxidative stress in the substantia nigra and striatum were investigated through Western blot and immunohistochemical staining. Key findings Treadmill training improved the performance of gait parameters in terms of maximal area, swing speed, stride length, and stance phase; treadmill training also reduced methamphetamine-induced rotation. This training not only improved dopaminergic neuron viability but also recovered mitochondrial function and attenuated oxidative stress in PD rats. The mechanism may be associated with the facilitation of mitochondrial turnover, including facilitation of mitochondrial fusion, fission, and clearance accompanying increased quantities of mitochondria. Significance Treadmill exercise improved gait speed and balance, reduced oxidative stress, improved mitochondrial fusion and fission, increased mitochondrial amounts, and potentially attenuated dopaminergic neuron degeneration. Consequently, mitochondrial quality was improved in PD rats.

BACKGROUND Exercise is an effective therapy for the management of diabetes because it helps regulate glucose and magnesium homeostasis. Nevertheless, the mechanisms by which exercise exerts effects on magnesium transport remain unclear. This study investigated the expression of genes encoding magnesium transporters (GMTs) after a three-month exercise program in diabetic patients. METHODS This study was conducted with a within-subject pre-post design. A total of 15 adult patients with type 2 diabetes mellitus (T2DM) were recruited and underwent a three-month indoor bicycle exercise program. The expression of five GMTs (CNNM2, TRPM6, TRPM7, SLC41A1, and SLC41A3) was determined in blood samples. Relevant anthropometric values and biochemical parameters were also determined. RESULTS Although the body weight and body mass index decreased after three months exercise, there were no significant differences. Fasting blood glucose, glycated hemoglobin (HbA1c), waist circumference, and magnesium levels decreased after the exercise program (p < 0.05). The expression of SLC41A1 and SLC41A3 were downregulated after exercise, but only CNNM2, TRPM6, and TRPM7 showed significantly decreased expression levels compared with those before the exercise program (p < 0.05). CONCLUSION The three-month exercise program ameliorated blood glucose levels and downregulated the expression of magnesium-responsive genes in patients with T2DM.

Transferring exogenous mitochondria has therapeutic effects on damaged heart, liver, and lung tissues. Whether this protective effect requires the symbiosis of exogenous mitochondria in host cells remains unknown. Here xenogenic mitochondria derived from a hamster cell line were applied to ischemic rat brains and rat primary cortical neurons. Isolated hamster mitochondria, either through local intracerebral or systemic intra-arterial injection, significantly restored the motor performance of brain-ischemic rats. The brain infarct area and neuronal cell death were both attenuated by the exogenous mitochondria. Although internalized mitochondria could be observed in neurons and astrocytes, the low efficacy of mitochondrial internalization could not completely account for the high rate of rescue of the treated neural cells. We further illustrated that disrupting electron transport or ATPase synthase in mitochondria significantly attenuated the protective effect, suggesting that intact respiratory activity is essential for the mitochondrial potency on neural protection. These results emphasize that nonsymbiotic extracellular mitochondria can provide an effective cell defense against acute injurious ischemic stress in the central nervous system.

Diet and exercise are conventional methods for controlling body weight and are linked to alterations in gut microbiota. However, the associations of diet, exercise, and gut microbiota in the control of obesity remain largely unknown. In the present study, using 16S rRNA amplicon sequencing and fecal microbiota transplantation (FMT), normal fat diet (NFD), exercise and their combination resulted in improved metabolic profiles in comparison to sedentary lifestyle with high fat diet (HFD). Moreover, diet exerted more influence than exercise in shaping the gut microbiota. HFD-fed mice receiving FMT from NFD-exercised donors not only showed remarkably reduced food efficacy, but also mitigated metabolic profiles (p Helicobacter, Odoribacter and AF12 and overrepresentation of oxidative phosphorylation and glycolysis genes. Our findings demonstrate that the beneficial effects of diet and exercise are transmissible via FMT, suggesting a potential therapeutic treatment for obesity.

We aimed to investigate expression of magnesium transporter genes in patients with head and neck cancer who underwent cisplatin-based neoadjuvant chemotherapy and their association with serum magnesium level. Head and neck cancer patients scheduled to undergo neoadjuvant cisplatin-based chemotherapy were eligible for enrollment. Blood samples were obtained at three time points: prior to, during, and after completion of chemotherapy. Expression levels of magnesium transporter genes were determined by quantitative real-time PCR. A total of 23 patients were included in the final analysis. The average serum magnesium levels dropped 6.98 and 5.20% during and after completion of chemotherapy. There were neither significant associations between serum magnesium level and demographic variables nor tumor-related variables. SLC41A1 expression level was positively correlated with serum magnesium whereas TRPM6 expression level was negatively correlated with serum magnesium. Serum magnesium level decreased during cisplatin-based chemotherapy in head and neck cancer patients. Further studies are warranted to investigate optimal magnesium measurement and substitution protocol.

The cell penetrating peptide, Pep-1, has been shown to facilitate cellular uptake of foreign mitochondria but further research is required to evaluate the use of Pep-1-mediated mitochondrial delivery (PMD) in treating mitochondrial defects. Presently, we sought to determine whether mitochondrial transplantation rescue mitochondrial function in a cybrid cell model of mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) disease. Following PMD, recipient cells had internalized donor mitochondria after 1 h, and expressed higher levels of normal mitochondrial DNA, particularly at the end of the treatment and 11 days later. After 4 days, mitochondrial respiratory function had recovered and biogenesis was evident in the Pep-1 and PMD groups, compared to the untreated MELAS group. However, only PMD was able to reverse the fusion-to-fission ratio of mitochondrial morphology, and mitochondria shaping proteins resembled the normal pattern seen in the control group. Cell survival following hydrogen peroxide-induced oxidative stress was also improved in the PMD group. Finally, we observed that PMD partially normalized cytokine expression, including that of interleukin (IL)-7, granulocyte macrophage–colony-stimulating factor (GM-CSF), and vascular endothelial growth factor (VEGF), in the MELAS cells. Presently, our data further confirm the protective effects of PMD as well in MELAS disease.

Background Intermittent parathyroid hormone (PTH) can be used to treat osteoporosis of the spine and hip. However, whether it can be used to treat osteoporosis of the mandible is unclear. The purpose of this study was to explore the influence of applying intermittent PTH to ovariectomized rats on the trabecular bone microarchitecture of the mandible and femoral head. Methods Eighteen female rats were divided into three groups: the healthy group, ovariectomized (OVX) group, and OVX + PTH group. The OVX group and OVX + PTH group had an OVX at 8 weeks of age. The OVX + PTH group received intermittent PTH therapy for 12 weeks. The mandibles and femurs of all rats were removed at 20 weeks and were then scanned using microcomputed tomography (micro-CT). Results From the micro-CT analysis, the trabecular bone microarchitecture of the mandible and femoral head are offered as follows: (1) The bone volume fraction and trabecular thickness in the OVX group were lower than those in the healthy group. (2) The bone volume fraction and trabecular thickness in the OVX + PTH group approximated those in the healthy group. Conclusion The conclusions of this study regarding the trabecular bone microarchitecture of the mandible and femoral head are offered as follows: (1) The BV/TV and TbTh in the OVX group were lower than those in the healthy group. (2) The BV/TV and TbTh in the OVX + PTH group approximated those in the healthy group, therefore, intermittent PTH displayed high efficacy for treating femoral or mandibular deterioration of bone microstructure resulting from loss of ovarian function. Osteoporosis of the femur or mandible in the rats was ameliorated by intermittent PTH therapy.

Aims/Introduction The aim of the present study was to investigate an appropriate level of physical activity and optimal dietary intake in older type 2 diabetes patients. Materials and Methods The cross-sectional study enrolled 210 older type 2 diabetes patients. Participants were interviewed to obtain information on physical activity, 24-h dietary recall and typical weekly dietary patterns. Anthropometric measurements, and biochemical analysis of blood and urine were determined. Results Moderate physical activity (either moderate leisure-time physical activity or moderate physical activity level) and diet with protein intake of ≥0.8 g/kg/day were associated with lower glycated hemoglobin and triglyceride, higher high-density lipoprotein, lower waist circumference, body mass index and body fat, as well as better serum magnesium and albumin levels in older diabetic patients. In contrast, inadequate protein intake was correlated with higher glycated hemoglobin, triglyceride, body fat percentage, waist circumference and body mass index. In addition, high physical activity with inadequate protein and magnesium intake might exacerbate magnesium deficiency, resulting in poor glycemic control in older diabetic patients. Furthermore, low physical activity and inadequate protein intake were linked with poor glycemic control, and lower high-density lipoprotein, and higher triglyceride, body fat percentage, waist circumference and body mass index. Conclusions Moderate physical activity and adequate dietary protein intake (≥0.8 g/kg/day) might be the optimal recommendation for better metabolic control in older adults with type 2 diabetes.

Object Mobilization of hematopoietic progenitor cells (HPCs) from bone marrow involved in the process of peripheral nerve regeneration occurs mostly through deposits of CD34+ cells. Treadmill exercise, with either differing intensity or duration, has been shown to increase axon regeneration and sprouting, but the effect of mobilization of HPCs on peripheral nerve regeneration due to treadmill exercise has not yet been elucidated. Methods Peripheral nerve injury was induced in Sprague-Dawley rats by crushing the left sciatic nerve using a vessel clamp. The animals were categorized into 2 groups: those with and without treadmill exercise (20 m/min for 60 minutes per day for 7 days). Cytospin and flow cytometry were used to determine bone marrow progenitor cell density and distribution. Neurobehavioral analysis, electrophysiological study, and regeneration marker expression were investigated at 1 and 3 weeks after exercise. The accumulation of HPCs, immune cells, and angiogenesis factors in injured nerves was determined. A separate chimeric mice study was conducted to assess CD34+ cell distribution according to treadmill exercise group. Results Treadmill exercise significantly promoted nerve regeneration. Increased Schwann cell proliferation, increased neurofilament expression, and decreased Schwann cell apoptosis were observed 7 days after treadmill exercise. Elevated expression of S100 and Luxol fast blue, as well as decreased numbers of vacuoles, were identified in the crushed nerve 3 weeks after treadmill exercise. Significantly increased numbers of mononuclear cells, particularly CD34+ cells, were induced in bone marrow after treadmill exercise. The deposition of CD34+ cells was abolished by bone marrow irradiation. In addition, deposits of CD34+ cells in crushed nerves paralleled the elevated expressions of von Willebrand factor, isolectin B4, and vascular endothelial growth factor. Conclusions Bone marrow HPCs, especially CD34+ cells, were able to be mobilized by low-intensity treadmill exercise, and this effect paralleled the significant expression of angiogenesis factors. Treadmill exercise stimulation of HPC mobilization during peripheral nerve regeneration could be used as a therapy in human beings.

Object Human amniotic fluid–derived mesenchymal stem cells (AFMSCs) have been shown to promote peripheral nerve regeneration. The expression of stromal cell–derived factor-1α (SDF-1α) in the injured nerve exerts a trophic effect by recruiting progenitor cells that promote nerve regeneration. In this study, the authors investigated the feasibility of intravenous administration of AFMSCs according to SDF-1α expression time profiles to facilitate neural regeneration in a sciatic nerve crush injury model. Methods Peripheral nerve injury was induced in 63 Sprague-Dawley rats by crushing the left sciatic nerve using a vessel clamp. The animals were randomized into 1 of 3 groups: Group I, crush injury as the control; Group II, crush injury and intravenous administration of AFMSCs (5 × 106 cells for 3 days) immediately after injury (early administration); and Group III, crush injury and intravenous administration of AFMSCs (5 × 106 cells for 3 days) 7 days after injury (late administration). Evaluation of neurobehavior, electrophysiological study, and assessment of regeneration markers were conducted every week after injury. The expression of SDF-1α and neurotrophic factors and the distribution of AFMSCs in various time profiles were also assessed. Results Stromal cell–derived factor-1α increased the migration and wound healing of AFMSCs in vitro, and the migration ability was dose dependent. Crush injury induced the expression of SDF-1α at a peak of 10–14 days either in nerve or muscle, and this increased expression paralleled the expression of its receptor, chemokine receptor type-4 (CXCR-4). Most AFMSCs were distributed to the lung during early or late administration. Significant deposition of AFMSCs in nerve and muscle only occurred in the late administration group. Significantly enhanced neurobehavior, electrophysiological function, nerve myelination, and expression of neurotrophic factors and acetylcholine receptor were demonstrated in the late administration group. Conclusions Amniotic fluid–derived mesenchymal stem cells can be recruited by expression of SDF-1α in muscle and nerve after nerve crush injury. The increased deposition of AFMSCs paralleled the expression profiles of SDF-1α and its receptor CXCR-4 in either muscle or nerve. Administration of AFMSCs led to improvements in neurobehavior and expression of regeneration markers. Intravenous administration of AFMSCs may be a promising alternative treatment strategy in peripheral nerve disorder.

Object Increased integration of CD34+ cells in injured nerve significantly promotes nerve regeneration, but this effect can be counteracted by limited migration and short survival of CD34+ cells. SDF-1α and its receptor mediate the recruitment of CD34+ cells involved in the repair mechanism of several neurological diseases. In this study, the authors investigate the potentiation of CD34+ cell recruitment triggered by SDF-1α and the involvement of CD34+ cells in peripheral nerve regeneration. Methods Peripheral nerve injury was induced in 147 Sprague-Dawley rats by crushing the left sciatic nerve with a vessel clamp. The animals were allocated to 3 groups: Group 1, crush injury (controls); Group 2, crush injury and local application of SDF-1α recombinant proteins; and Group 3, crush injury and local application of SDF-1α antibody. Electrophysiological studies and assessment of regeneration markers were conducted at 4 weeks after injury; neurobehavioral studies were conducted at 1, 2, 3, and 4 weeks after injury. The expression of SDF-1α, accumulation of CD34+ cells, immune cells, and angiogenesis factors in injured nerves were evaluated at 1, 3, 7, 10, 14, 21, and 28 days after injury. Results Application of SDF-1α increased the migration of CD34+ cells in vitro, and this effect was dose dependent. Crush injury induced the expression of SDF-1α, with a peak of 10–14 days postinjury, and this increased expression of SDF-1α paralleled the deposition of CD34+ cells, expression of VEGF, and expression of neurofilament. These effects were further enhanced by the administration of SDF-1α recombinant protein and abolished by administration of SDF-1α antibody. Furthermore, these effects were consistent with improvement in measures of neurological function such as sciatic function index, electrophysiological parameters, muscle weight, and myelination of regenerative nerve. Conclusions Expression of SDF-1α facilitates recruitment of CD34+ cells in peripheral nerve injury. The increased deposition of CD34+ cells paralleled significant expression of angiogenesis factors and was consistent with improvement of neurological function. Utilization of SDF-1α for enhancing the recruitment of CD34+ cells involved in peripheral nerve regeneration may be considered as an alternative treatment strategy in peripheral nerve disorders.

Traumatic brain injury (TBI) results in neurological dysfunction and death through primary or secondary mechanisms. Here, we evaluated the effect of osmotic pump delivery of granulocyte colony-stimulating factor (G-CSF) on the histopathology and motor function recovery of rats after experimental TBI.Sprague-Dawley rats were used as experimental model by fluid percussion device to cause brain injury on the motor cortex area. The rats were simultaneously subjected to TBI and were implanted of min-osmotic pump containing recombinant human G-CSF (300 μg/700 μl) via intraperitoneal injection. Motor function was assessed by rotarod test. 5-bromo-2'-deoxyuridine (BrdU) was used to label the proliferating cells and their differentiation was evaluated by histology and immunohistochemistry.The G-CSF group showed significantly better motor function recovery than the control group, and the effect lasted up to 14 days after TBI. Moreover, the G-CSF group exhibited a greater increase in the number of BrdU-positive cells compared with the control group. The G-CSF group also had a significantly higher number of DCX-positive cells in the ipsilateral subventricular zone (SVZ) than the control group.These data suggest that the beneficial effect of delivering G-CSF via an osmotic pump may improve the motor function and enhance neurogenesis in the SVZ of the injured brain.

BACKGROUND Statins have therapeutic benefits for the management of several disorders. A short-term course of a high-dose statin pretreatment has demonstrated neuroprotective effects against neurological diseases. However, the molecular basis underlying the neuroprotective action of statins remains unclear. OBJECTIVE We investigated whether a short-term course of high-dose atorvastatin pretreatment has beneficial effects in protecting sciatic nerve from crush injury. METHODS Atorvastatin (5 mg/kg) or saline was given orally to Sprague-Dawley rats for 7 days before injury. The rats were subjected to crush injury in the left sciatic nerve with a vessel clamp. Biochemical, functional, electrophysiological, and morphological alterations occurring during injury-induced degeneration/regeneration were examined. RESULTS Atorvastatin improved injury-induced neurobehavioral/electrophysiological changes and axonal loss. Damage-associated alterations, including structural disruption, oxidative stress, inflammation, and apoptosis, were attenuated by atorvastatin. After injury, regeneration-associated genes, including growth-associated protein-43, myelin basic protein, ciliary neurotrophic factor, and collagen, were upregulated by atorvastatin. The suppression of extracellular signal-regulated kinase, AKT, signal transducer and activators of transcription-1, and necrosis factor-kappaB and the elevated activation of c-Jun N-terminal kinase, Smad2/3, and activating protein-1 were associated with the neuroprotective action of atorvastatin. CONCLUSION These findings suggest that a short-term course of high-dose atorvastatin pretreatment can protect against sciatic nerve crush injury through modifying intracellular or extracellular environments, making it favorable for regeneration.

Object Human amniotic fluid–derived mesenchymal stem cells (AFMSCs) have been shown to promote peripheral nerve regeneration, and the local delivery of neurotrophic factors may additionally enhance nerve regeneration capacity. The present study evaluates whether the transplantation of glia cell line–derived neurotrophic factor (GDNF)–modified human AFMSCs may enhance regeneration of sciatic nerve after a crush injury. Methods Peripheral nerve injury was produced in Sprague-Dawley rats by crushing the left sciatic nerve using a vessel clamp. Either GDNF-modified human AFMSCs or human AFMSCs were embedded in Matrigel and delivered to the injured nerve. Motor function and electrophysiological studies were conducted after 1 and 4 weeks. Early or later nerve regeneration markers were used to evaluate nerve regeneration. The expression of GDNF in the transplanted human AFMSCs and GDNF-modified human AFMSCs was monitored at 7-day intervals. Results Human AFMSCs were successfully transfected with adenovirus, and a significant amount of GDNF was detected in human AFMSCs or the culture medium supernatant. Increases in the sciatic nerve function index, the compound muscle action potential ratio, conduction latency, and muscle weight were found in the groups treated with human AFMSCs or GDNF-modified human AFMSCs. Importantly, the GDNF-modified human AFMSCs induced the greatest improvement. Expression of markers of early nerve regeneration, such as increased expression of neurofilament and BrdU and reduced Schwann cell apoptosis, as well as late regeneration markers, consisting of reduced vacuole counts, increased expression of Luxol fast blue and S100 protein, paralleled the results of motor function. The expression of GDNF in GDNF-modified human AFMSCs was demonstrated up to 4 weeks; however, the expression decreased over time. Conclusions The GDNF-modified human AFMSCs appeared to promote nerve regeneration. The consecutive expression of GDNF was demonstrated in GDNF-modified human AFMSCs up to 4 weeks. These findings support a nerve regeneration scenario involving cell transplantation with additional neurotrophic factor secretion.

Granulocyte colony-stimulating factor (G-CSF) demonstrates neuroprotective effects through different mechanisms, including mobilization of bone marrow cells. However, the influence of G-CSF-mediated mobilization of bone marrow-derived cells on injured sciatic nerves remains to be elucidated. The administration of G-CSF promoted a short-term functional recovery 7 days after crush injury in sciatic nerves. A double-immunofluorescence study using green fluorescent protein-chimeric mice revealed that bone marrow-derived CD34+ cells were predominantly mobilized and migrated into injured nerves after G-CSF treatment. G-CSF-mediated beneficial effects against sciatic nerve injury were associated with increased CD34+ cell deposition, vascular endothelial growth factor (VEGF) expression, and vascularization/angiogenesis as well as decreased CD68+ cell accumulation. However, cell differentiation and VEGF expression were not demonstrated in deposited cells. The results suggest that the promotion of short-term functional recovery in sciatic nerve crush injury by G-CSF involves a paracrine modulatory effect and a bone marrow-derived CD34+ cell mobilizing effect.

Purpose Attenuation of pro-inflammatory cytokines and associated inflammatory cell deposits rescues human amniotic fluid mesenchymal stem cells (AFS) from apoptosis. Hyperbaric oxygen (HBO) suppressed stimulus-induced pro-inflammatory cytokine production in blood-derived monocyte-macrophages. Herein, we evaluate the beneficial effect of hyperbaric oxygen on transplanted AFS in a sciatic nerve injury model. Methods Peripheral nerve injury was produced in Sprague-Dawley rats by crushing the left sciatic nerve using a vessel clamp. The AFS were embedded in fibrin glue and delivered to the injured site. Hyperbaric oxygen (100% oxygen, 2 ATA, 60 min/day) was administered 12 h after operation for seven consecutive days. Transplanted cell apoptosis, oxidative stress, inflammatory cell deposits and associated chemokines, pro-inflammatory cytokines, motor function, and nerve regeneration were evaluated 7 and 28 days after injury. Results Crush injury induced an inflammatory response, disrupted nerve integrity, and impaired nerve function in the sciatic nerve. However, crush injury-provoked inflammatory cytokines, deposits of inflammatory cytokines, and associated macrophage migration chemokines were attenuated in groups receiving hyperbaric oxygen but not in the AFS-only group. No significant increase in oxidative stress was observed after administration of HBO. In transplanted AFS, marked apoptosis was detected and this event was reduced by HBO treatment. Increased nerve myelination and improved motor function were observed in AFS-transplant, HBO-administrated, and AFS/HBO-combined treatment groups. Significantly, the AFS/HBO combined treatment showed the most beneficial effect. Conclusion AFS in combination with HBO augment peripheral nerve regeneration, which may involve the suppression of apoptotic death in implanted AFS and the attenuation of an inflammatory response detrimental to peripheral nerve regeneration.

Detection of the myocardial damage in the early stage of subarachnoid hemorrhage (SAH) is impossible without a good animal model. We investigated the feasibility of using immunohistochemical cardiac troponin I (cTnI) staining to detect the early myocardial damage in rats subject to SAH by endovascular perforation. SAH induced increases in mean blood pressure, heart rate, intracranial pressure, plasma norepinephrine and cTnI accompanied with electrocardiogram abnormalities. The heart was dilated. The myocardium revealed coagulative myocytolysis and remarkable loss of myocardial tissue cTnI in myocytolytic areas within 3 h after SAH. Thus, we create a rat SAH model that can be applied in studying the mechanisms of the early myocardial damage following SAH and for evaluating therapeutic strategies in SAH patients.

Granulocyte colony-stimulating factor (G-CSF) inhibits programmed cell death and stimulates neuronal progenitor differentiation. Neuronal stem cells transplanted into injured spinal cord can survive, differentiating into astroglia and oligodendroglia, and supporting axon growth and myelination. Herein, we evaluate the combined effects of G-CSF and neuronal stem cells on spinal cord injury. For 40 Sprague-Dawley rats (n=10 in each group) transverse spinal cord resections at the T8-9 level were carried out, leaving an approximately 2-mm gap between the distal and proximal ends of the cord. Neuronal stem cells embedded in fibrin glue treated with or without G-CSF (50 microg/kg x 5 days) (groups III and IV) or fibrin glue with or without G-CSF (50 microg/kg x 5 days) (groups I and II) were transplanted into the gap in the injured spinal cord. Spinal cord regeneration was assessed using a clinical locomotor rating scale scores and electrophysiological, histological and immunohistochemical analysis 3 months after injury. Regeneration was more advanced in group IV than in groups III or II according to the clinical motor score, motor evoked potential, and conduction latency. Most advanced cord regeneration across the gap was observed in group IV rats. Higher densities of bromodeoxyuridine in the injured area and higher expression levels of Neu-N and MAP-2 over the distal end of the injured spinal cord were observed in group IV compared with groups II or III, but there was no significant difference in expression of glial fibrillary acid protein. This synergy between G-CSF and neuronal stem cells may be due to increased proliferation of progenitor cells in the injured area and increased expression of neuronal stem cell markers extrinsically or intrinsically in the distal end of injured cord.

Aim: To examine if magnesium lithospermate B (MLB) extracted from Danshen, the dried roots of Salvia miltiorrhiza , may act as an active component responsible for the cardiac therapeutic effect of this traditional Chinese herb via the same molecular mechanism triggered by cardiac glycosides, such as ouabain and digoxin. Moreover, we wanted to test if MLB may provide neuroprotection against ischemic stroke as observed for cardiac glycosides. Methods: Similarity in the chemical structure and molecular configuration between MLB and ouabain was analyzed. The inhibition potency of MLB and ouabain on Na + ,K + -ATPase activity of a commercial product, as well as in purified membrane fractions from rat brain and heart tissues, was examined and compared. Neuroprotective effect of MLB against ischemic stroke was also evaluated using a cortical brain slice-based assay model. Results: Dose-dependent inhibition on the commercial Na + ,K + - ATPase equivalent to that for ouabain was observed for MLB of approximately half dosage by weight. This relative potency of ouabain and MLB was also observed for their inhibition on Na + ,K + -ATPase activity of plasma membrane purified from rat tissues, although these 2 inhibitors exhibited somewhat lower competence in these crude extracts. In ischemic gerbil brains, post-treatment with MLB significantly reduced the infarct size, visualized by 2,3,5-triphenyltetrazolium chloride staining, by approximately 55% when compared with the control group. Conclusion: These results evidently suggest that the cardiac therapeutic effect of Danshen should be at least partly attributed to the effective inhibition of Na + ,K + - ATPase by MLB, and that MLB provides anti-ischemic neuroprotection in gerbils subjected to focal ischemia and reperfusion.

Microglia-derived protection of brain cells (microglia, astrocytes, and neurons) during in vitro ischemic stress (deprivation of glucose, oxygen, and serum) was determined. Trypan blue exclusion assay, immunoblocking assay, Western blot analysis, and ELISA assay were used to determine the molecular mechanisms responsible for the microglia-derived protection. Results demonstrated that supernatants from the ischemic microglia protected all three cell-types from ischemia-induced damage by releasing the transforming growth factor-beta1 (TGF-beta1) and glial cell line-derived neurotrophic factor (GDNF). The protection of microglia was TGF-beta1 related, whereas astrocytes protection was GDNF-dependent. The protection of neurons was TGF-beta1 and GDNF independent, and the molecular nature responsible for their protection remains to be determined. These results indicate contribution from the surrounding cells and the types of receptors expressed on different brain cells probably also play an important role in determining their fate against ischemia.

The aim of this study was to develop a microdialysis-graphite furnace atomic absorption spectroscopy (MD-GFAAS) for monitoring dynamic changes of extracellular magnesium (Mg) and zinc (Zn) in the cortex of gerbils subjected to focal cerebral ischemia, that had been produced in anesthetized gerbils by occlusion of the right middle cerebral artery.Two microdialysis probes were inserted into both sides of the cortex to simultaneously collect dialysates during cerebral ischemia. Dynamic changes in these analytes, on ipsilateral and contralateral sides of the brain, were assayed by MD-GFAAS. Optimal conditions and analytical precision of GFAAS were studied in the present assay.The present study demonstrated significant decreases in Mg (65% of baseline) and zinc (74% of baseline) maintained their levels within 3 h on the ipsilateral side of cortex during cerebral ischemia. Slight changes of Mg and Zn on the contralateral sides were also observed.The derangement of extracellular Mg and Zn could be important in the progression of cell injury and may be associated with cerebral ischemia insult.

The present study examined effects of the combined administration of naloxone (NX) and indomethacin (IM) on nigrostriatal catecholamines and locomotor activity after intranigral lipopolysaccharide (LPS) injection in Sprague-Dawley rats. NX plus IM was given 3 days after LPS injection; it significantly (P < .05) reversed LPS inflammation on nigrostriatal dopamine (DA) and nigral serotonin (5-HT) and nigral homovanillic acid (HVA)/DA ratio and nigrostriatal 5-hydroxyindoleacetic acid (5-HIAA)/5-HT ratio. It also tended to ameliorate the locomotor hyperactivity. However, NX plus IM given 30 min before LPS could not satisfactorily protect against LPS's damage both biochemically and behaviorally. These results reveal that NX plus IM may protect against LPS on DA, 5-HT, and motor function after LPS injection but not before. Thus it suggests that the combined treatment of NX and IM gives a potent therapy, but not prevention, of LPS-induced inflammation and also protect nigrostriatal dopaminergic and serotoninergic systems against LPS in rats.

The present study was designed to evaluate the neuroprotective effects of Ginkgo biloba leaf extract (EGb761) in male gerbils subjected to focal cerebral ischemia produced by permanent occlusion of the right middle cerebral artery. In this study, gerbils were fed standard chow with or without EGb761 (100 mg/kg/day, i.g.) prior to cerebral ischemia for 1 week. Gerbils were anesthetized and craniectomized to expose the right middle cerebral artery (MCA). The right MCA was constricted with an 8-0 suture to produce a permanent ligation. Infarct volume was assessed by TTC (2,3,5-triphenyl-tetrazolium chloride) staining 24 hours after initiation of cerebral ischemia. Results showed that the EGb761 group had significant reduction of infarct volume 4 and 6 mm from the frontal pole by 40% and 30%, respectively when compared to the control group ( p < 0.05). Mean locomotor activity of gerbils was reduced 24 hours after the occlusion of the MCA in both groups. However, there was no difference in locomotor activity between groups either 30 minutes before or 24 hours after the occlusion ( p < 0.05).

The aim of this study is to investigate the impact of serum Mg on bone mineral metabolism in chronic kidney disease (CKD) patients with or without diabetes. A total of 56 CKD patients not receiving dialysis were recruited and divided into two groups, one group of 27 CKD patients with diabetes and another group of 29 CKD patients without diabetes. Biochemical determinations were made, and the estimated glomerular filtration rate (eGFR) was measured. Bone mineral density was measured by dual-energy X-ray absorptiometry. Serum Mg was inversely correlated with serum CaP=0.023and positively correlated with serum parathyroid hormone (PTH)P=0.020, alkaline phosphataseP=0.044, and phosphateP=0.040in the CKD patients with diabetes. The CKD patients with diabetes had lower serum albumin and a higher proportion of hypomagnesemia and osteoporosis than the nondiabetic patients didP<0.05. Serum Mg was inversely correlated with eGFR in the CKD patients with or without diabetesP<0.05. Serum Mg showed an inverse correlation with 25-hydroxyvitamin D in CKD patients without diabetesP=0.006. Furthermore, the diabetic CKD patients with low serum Mg had a lower iPTHP=0.007and a higher serum Ca/Mg ratioP<0.001than the other CKD patients. The lower serum Mg subgroup showed a higher incidence of osteoporosis than the moderate and higher serum Mg subgroups did (66.7%, 39.4%, and 29.4%, resp.). In conclusion, low serum Mg may impact iPTH and exacerbates osteoporosis in CKD patients, particularly with diabetes.

Background : A method for determining extracellular magnesium (Mg) levels in gerbil brain dialysates was developed by microdialysis and graphite furnace atomic absorption spectroscopy (GFAAS). Methods : Two microdialysis probes were inserted into the right and left cortices of a gerbil subjected to a focal cerebral ischemia. Extracellular magnesium concentrations in diluted dialysates were 1.10 and 1.12 ppb in the ipsilateral and contralateral gerbil cortex, respectively. Results : During cerebral ischemia, these concentrations decreased significantly to approximately 60% of basal in the ipsilateral cortex, whereas no changes in the contralateral cortex were detected. Extracellular magnesium concentrations returned to baseline within 3 h of reperfusion. The linearity of magnesium concentrations ranged from 0.50 to 5.0 ppb with a detection limit of 0.03 ppb in the present assay. A complete analysis can be performed within 2 min. The intra- and interassay precision was Conclusion : To our knowledge, the present method is the first analytical assay measuring dynamic extracellular magnesium concentrations during cerebral ischemia by microdialysis and graphite furnace atomic absorption spectroscopy.

Buckminsterfullerence and its derivatives have recently been shown to exhibit considerable in vivo biological activities. A water-soluble hexasulfonated C 60 (FC 4 S) has been shown to protect against oxidative stress. Neuroprotective effects of FC 4 S were investigated in the present study. Focal cerebral ischemia was produced by a permanent occlusion of the right middle cerebral artery in gerbils. Infarct volumes were determined by 2,3,5-triphenyltetrazolium chloride transcardiac perfusion 24 h after cerebral ischemia. Chronic pretreatment of FC 4 S (0.5 and 5.0 mg/kg/day, intraperitoneally for 2 weeks) significantly reduced the infarct volume (by 42% and 68%, respectively) when compared to that of the control group. Results revealed that chronic pretreatment of FC 4 S may protect the brain against focal cerebral ischemia.

A dual-probe microdialysis technique was developed for the simultaneous monitoring of glucose and related metabolite levels during testicular ischemia in rats. The determinations of lactate and pyruvate were achieved by liquid chromatography within 5 min. Glucose was determined by a microdialysis analyzer. A unilateral ligation was produced by occlusion of the right artery for 2 or 4 h in anesthetized rats. Microdialysis probes were inserted in both sides of the testis to simultaneously monitor glucose, lactate and pyruvate during basal, ischemia and reperfusion periods. Dynamic and comparative changes in these analytes in ipsilateral and contralateral testes were demonstrated. The present technique can be used as a tool for exploring energy related metabolites and their relationships in testicular ischemia.

The aim of this study was to monitor dynamic changes in energy-related metabolites in the cortex of gerbils subjected to cerebral ischemia by a dual probe microdialysis technique. Focal cerebral ischemia was produced in anesthetized gerbils by occlusion of the right common carotid artery and the right middle cerebral artery for 60 min. Two microdialysis probes were inserted into both sides of the cortex to simultaneously monitor extracellular glucose, lactate, pyruvate and glutamate. Dynamic and comparative changes in these analytes, on the ipsilateral and contralateral sides of the brain, were simultaneously monitored by liquid chromatography and a microdialysis analyzer. The present study demonstrated decreases in glucose and pyruvate, increases in lactate and glutamate on the ipsilateral side whereas all analytes remain constant on the contralateral side of cortex during cerebral ischemia. In vitro recovery of each microdialysis probe was performed to ensure the quality of experiments. The detection limits of pyruvate, glutamate, lactate and glucose were 0.2, 1.0, 2.0 and 20 microM, respectively. The intra- and inter-assay correlations were less than 5% in standard mixtures and pooled brain dialysates.

In vivo microdialysis coupled with liquid chromatography was developed for the continuous monitoring of brain neurochemicals during cerebral ischemia in awake, free moving gerbils. The dead volume of the microdialysis system was estimated to be less than 30 microl. The detection limits of the present assay were 0.2 to 2.0 microM for analytes at a signal to noise ratio of five. To validate this assay, a focal cerebral ischemia was produced by occlusion of one common carotid artery for 60 min and then reperfusion for additional 3 h in awake gerbils. A microdialysis probe was inserted into the striatum of the gerbil. Dialysates were autoinjected and analyzed extracellular pyruvate, lactate, and ascorbic acid by liquid chromatography with a UV detector during cerebral ischemia. Significant changes of pyruvate and the lactate/pyruvate ratio were observed. Biphasic and dynamic changes in ascorbic acid and lactate were proposed to correlate a secondary damage. This assay can be used as a tool to study dynamic changes of brain neurochemicals in awake animals.

A dual-probe microdialysis technique coupled with liquid chromatographic assays was developed for the simultaneous monitoring of neurochemicals in gerbil striata during cerebral ischemia. Isocratic separation of lactate and pyruvate was achieved within 5 min whereas the separation of biogenic amines was completed within 30 min. An unilateral ligation was produced by occlusion of the right common carotid artery for 30 mins in anethetized gerbils to perform a typical focal cerebral ischemia. Microdialysis probes were inserted in both sides of the striata to simultaneously monitor biogenic amines, lactate and pyruvate during cerebral ischemia. Dynamic and comparative changes of these analytes in ipsilateral and contralateral sides of the brain can be simultaneously measured by the assay. The present assay can be used as a research tool to explore neurochemical substances and their relationships during cerebral ischemia.

To mimic chronic exposure to neurotoxins in inducing dopaminergic cell damage, multiple doses of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were injected in C57BL/6 mice. Effects of pre- and post-treatment with the glial cell line-derived neurotrophic factor (GDNF) by injections into the striatum were investigated. GDNF exerts protective and reverse effects on the dopaminergic damage, supporting the potential application of GDNF in prevention and treatment of Parkinson's disease.

Glutathione (GSH), present in a high concentration in the liver, serves important protective functions. We investigated the effect of lowered tissue GSH content, accomplished by diethylmaleate (DEM) administration, on liver extracellular GSH levels before and after global ischemia in anesthetized rats. Liver extracellular GSH levels were determined by microdialysis perfusion and an on-line high performance liquid chromatography system. Global liver ischemia was induced by ligation of the hepatic pedicles including the hepatic artery, portal vein, and bile duct. DEM (4 mmol/kg) significantly lowered both the liver tissue GSH levels (1.36 +/- 0.26 micromol/g wet wt vs 9.50 +/- 0.55 micromol/g wet wt for the untreated) and the liver extracellular GSH levels (4.3 +/- 2.4 microM vs 25.2 +/- 8.7 microM for the untreated). Global liver ischemia induced a dramatic increase in the liver extracellular GSH level. Although the liver tissue GSH level was lowered following DEM treatment, DEM administration did not affect significantly ischemia-induced elevation of extracellular GSH (when presented as fold increase relative to basal value). In conclusion, DEM showed a direct effect on liver extracellular GSH content in anesthetized rats. However, DEM treatment did not affect the relative release of GSH following global liver ischemia.

Twenty-two patients with Parkinson's disease (PD) were studied by clinical evaluation, assessments of dementia and depression, as well as electrophysiologic examinations for blink reflex (BR), cortical somatosensory evoked potentials (CSEP), brain stem, and long-latency auditory evoked potentials (BAEP, and LAEP), and cerebrospinal fluid (CSF) assays for monoamine metabolites. Results show that PD patients have a significant decrease of Mini-Mental State Examination (MMSE) scores (p < 0.05) and an increase of Hamilton Depression Scale (HDS) scores (p < 0.01), as well as a longer latencies of R2 in BR, N19 and P22 in CSEP, W4 and W5 in BAEP and P300 in LAEP (p < 0.01), and lower CSF levels of HVA and MHPG (p < 0.05). The findings suggest a correlation between dementia/depression and mesocorticolimbic and mesostriatocortic dysfunction with dopaminergic and noradrenergic deficiencies in PD patients. Furthermore, parkinsonian dementia parallels the length of duration of the disease, but not the severity of motor disability. Parkinsonian depression parallels both the length of duration of the disease and the severity of motor disability.

Background A new version of the CatWalk XT system was evaluated as a tool for detecting very subtle alteration in gait based on higher speed sample rate; the system could also demonstrate minor changes in neurological function. In this study, we evaluated the neurological outcome of sciatic nerve injury intervened by local injection of hyaluronic acid. Using the CatWalk XT system, we looked for differences between treated and untreated groups and differences within the same group as a function of time so as to assess the power of the Catwalk XT system for detecting subtle neurological change. Methods Peripheral nerve injury was induced in 36 Sprague–Dawley rats by crushing the left sciatic nerve using a vessel clamp. The animals were randomized into one of two groups: Group I: crush injury as the control; Group II: crush injury and local application with hyaluronic acid. These animals were subjected to neurobehavior assessment, histomorphology evaluation, and electrophysiology study periodically. These data were retrieved for statistical analysis. Results The density of neurofilament and S-100 over the distal end of crushed nerve showed significant differences either in inter-group comparison at various time points or intra-group comparison from 7 to 28 days. Neuronal structure architecture, axon counts, intensity of myelination, electrophysiology, and collagen deposition demonstrate significant differences between the two groups. There was significant difference of SFI and angle of ankle in inter- group analysis from 7 to 28 days, but there were no significant differences in SFI and angle of ankle at time points of 7 and 14 days. In the Cat Walk XT analysis, the intensity, print area, stance duration, and swing duration all showed detectable differences at 7, 14, 21, and 28 days, whereas there were no significant difference at 7 and 14 days with CatWalk 7 testing. In addition, there were no significant differences of step sequence or regularity index between the two versions. Conclusion Hyaluronic acid augmented nerve regeneration as early as 7 days after crush injury. This subtle neurological alteration could be detected through the CatWalk XT gait analysis but not the SFI, angle of ankle, or CatWalk 7 methods.

ObjectiveThis study compared the capabilities of dual-energy X-ray absorptiometry (DXA) and dental cone-beam computed tomography (CBCT) for predicting the cortical bone strength of rat femurs and tibias.Materials and methodsSpecimens of femurs and tibias obtained from 14 rats were first scanned with DXA to obtain the areal bone mineral density (BMD) of the midshaft cortical portion of the bones. The bones were then scanned using dental CBCT to measure the volumetric cortical bone mineral density (vCtBMD) and the cross-sectional moment of inertia (CSMI) for calculating the bone strength index (BSI). A three-point bending test was conducted to measure the fracture load of each femur and tibia. Bivariate linear Pearson analysis was used to calculate the correlation coefficients (r values) among the CBCT measurements, DXA measurements, and three-point bending parameters.ResultsThe correlation coefficients for the associations of the fracture load with areal BMD (measured using DXA), vCtBMD (measured using CBCT), CSMI (measured using CBCT), and BSI were 0.585 (p = 0.028) and 0.532 (p = 0.050) (for the femur and tibia, respectively), 0.638 (p = 0.014) and 0.762 (p = 0.002), 0.778 (p = 0.001) and 0.792 (pConclusionsCBCT was found to be superior to DXA for predicting cortical bone fracture loads in rat femurs and tibias. The BSI, which is a combined index of densitometric and geometric parameters, was especially useful. Further clinical studies are needed to validate the predictive value of BSI obtained from CBCT and should include testing on human cadaver specimens.

Magnesium sulfate (MgSO4) ameliorates focal ischemia-induced neuronal death in the rat and gerbil models. However, the molecular mechanisms for this neuroprotection are not known. Focal cerebral ischemia was produced by unilateral occlusion of the right common carotid artery and the right middle cerebral artery (CCAO + MCAO) for 30 min or 60 min. Treatment with MgSO4 significantly increased the level of mitogen-activated protein kinase/extra-cellular signal-regulated kinase kinase 1/2 (MEK1/2), extra-cellular signal-regulated kinase 1/2 (ERK1/2), cyclic-AMP response element binding protein (CREB) phosphorylation and the anti-apoptotic protein Bcl-2 both in the non-ischemic (contralateral) and ischemic (ipsilateral) cortex. However, these effects were reversed by administration of U0126, a MEK kinase inhibitor. In the ipsilateral cortex, a significant increase in the level of the proapoptotic proteins Bax, Bad, BNIP3 and activated caspase 3 were detected at the end of focal ischemia compared to the non-ischemic cortex. Treatment of MgSO4 prevented these ischemia-induced activations of the death cascade. Collectively, these data indicate that the ERK-CREB-Bcl-2 signaling pathway might be involved in MgSO4-induced neuroprotection following focal ischemia. Moreover, MgSO4 treatment also resulted in a reduction in pro-apoptotic proteins. These results enhance our understanding on the role of MgSO4 in treating cerebral ischemia.

Magnesium (Mg) supplements have been shown to significantly improve functional recovery in various neurological disorders. The essential benefits of Mg supplementation in peripheral nerve disorders have not been elucidated yet. The effect and mechanism of Mg supplementation on a sciatic nerve crush injury model was investigated. Sciatic nerve injury was induced in mice by crushing the left sciatic nerve. Mice were randomly divided into three groups with low-, basal- or high-Mg diets (corresponding to 10, 100 or 200% Mg of the basal diet). Neurobehavioral, electrophysiological and regeneration marker studies were conducted to explore nerve regeneration. First, a high Mg diet significantly increased plasma and nerve tissue Mg concentrations. In addition, Mg supplementation improved neurobehavioral, electrophysiological functions, enhanced regeneration marker, and reduced deposits of inflammatory cells as well as expression of inflammatory cytokines. Furthermore, reduced Schwann cell apoptosis was in line with the significant expression of bcl-2, bcl-X(L) and down-regulated expression of active caspase-3 and cytochrome C. In summary, improved neurological function recovery and enhanced nerve regeneration were found in mice with a sciatic nerve injury that were fed a high- Mg diet, and Schwann cells may have been rescued from apoptosis by the suppression of inflammatory responses.

Rosiglitazone is a potent synthetic peroxisome proliferator-activated receptor-gamma (PPAR-γ) agonist which improves glucose control in the plasma and reduces ischemic brain injury. However, the pharmacokinetics of rosiglitazone in the brain is still unclear. In this study, a method using liquid chromatography-mass spectrometry coupled with microdialysis and an auto-blood sampling system was developed to determine rosiglitazone and glucose concentration in the brain and blood of gerbils subjected to treatment with rosiglitazone (3.0 mg kg(-1), i.p.). The results showed the limit of detection was 0.04 μg L(-1) and the correlation coefficient was 0.9997 for the determination of rosiglitazone in the brain. The mean parameters, maximum drug concentration (C(max)) and the area under the concentration-time curve from time zero to time infinity (AUC(inf)), following rosiglitazone administration were 1.06±0.28 μg L(-1) and 296.82±44.67 μg min L(-1), respectively. The time to peak concentration (C(max) or T(max)) of rosiglitazone occurred at 105±17.10 min, and the mean elimination half-life (t(1/2)) from brain was 190.81±85.18 min after administration of rosiglitazone. The brain glucose levels decreased to 71% of the basal levels in the rosiglitazone-treated group when compared with those in the control (p

Although gait change is considered a useful indicator of severity in animal models of Parkinson's disease, systematic and extensive gait analysis in animal models of neurological deficits is not well established. The CatWalk-assisted automated gait analysis system provides a comprehensive way to assess a number of dynamic and static gait parameters simultaneously. In this study, we used the Catwalk system to investigate changes in gait parameters in adult rats with unilateral 6-OHDA-induced lesions and the rescue effect of dopaminergic neuron transplantation on gait function. Four weeks after 6-OHDA injection, the intensity and maximal area of contact were significantly decreased in the affected paws and the swing speed significantly decreased in all four paws. The relative distance between the hind paws also increased, suggesting that animals with unilateral 6-OHDA-induced lesions required all four paws to compensate for loss of balance function. At 8 weeks post-transplantation, engrafted dopaminergic neurons expressed tyrosine hydroxylase. In addition, the intensity, contact area, and swing speed of the four limbs increased and the distance between the hind paws decreased. Partial recovery of methamphetamine-induced rotational response was also noted.

Clearance of fibrin and associated inflammatory cytokines by tissue-type plasminogen activator (t-PA) is related to improved regeneration in neurological disorder. The biological activity of fermented soybean (natto) is very similar to that of t-PA. We investigated the effect of the dietary supplement of natto on peripheral nerve regeneration. The peripheral nerve injury was produced by crushing the left sciatic nerve with a vessel clamp in Sprague-Dawley rats. The injured animals were fed orally either with saline or natto (16 mg/day) for seven consecutive days after injury. Increased functional outcome such as sciatic nerve functional index, angle of ankle, compound muscle action potential and conduction latency were observed in natto-treated group. Histological examination demonstrated that natto treatment improved injury-induced vacuole formation, S-100 and vessel immunoreactivities and axon loss. Oral intake of natto prolonged prothrombin time and reduced fibrinogen but did not change activated partial thromboplastin time and bleeding time. Furthermore, natto decreased injury-induced fibrin deposition, indicating a tolerant fibrinolytic activity. The treatment of natto significantly improved injury-induced disruption of blood-nerve barrier and loss of matrix component such as laminin and fibronectin. Sciatic nerve crush injury induced elevation of tumor necrosis factor alpha (TNF-alpha) production and caused apoptosis. The increased production of TNF-alpha and apoptosis were attenuated by natto treatment. These findings indicate that oral intake of natto has the potential to augment regeneration in peripheral nerve injury, possibly mediated by the clearance of fibrin and decreased production of TNF-alpha.

Background Anastomosis of the nerve especially at narrow surgical field and presence of surgical tension is not easily accessible. DuraSeal demonstrates strong adhesive power without producing neurotoxicity. Herein, we evaluate the possibility of DuraSeal as a substitute in the repair of sciatic nerve gap injury. Materials and Methods The nerve gap model was constructed by excising the sciatic nerve (5 mm in length) in Sprague Dawley rats leaving a 5 mm nerve defect between nerve stumps. Animals were categorized into four groups: Group I: no treatment; Group II: 4 stitches suture; Group III: nerve approximation fixed by tissue glue; Group IV: nerve approximation fixed by DuraSeal. The motor function assessment included the CatWalk and SFI as well as electrophysiological studies. Nerve continuity and regeneration was examined at 1 and 8 wk after injury. The inflammatory cells, Schwann cell apoptosis, and Schwann cell proliferation were also investigated 1 wk after injury. Results The achievement of nerve continuity and myelination by DuraSeal approached that of suture demonstrated by crystal violet and Luxol Fast Blue staining at 1 and 8 wk, respectively. Motor function and electrophysiological parameters were restored in DuraSeal and suture group. Early expression of neurofilament and bromodeoxyuridine (BrdU) was also observed in these two groups. There was no statistically significant difference in deposits of macrophages and neutrophil cells or cell apoptosis among these four groups. Conclusions DuraSeal achieved the same nerve regeneration compared with that of suture and produced better regeneration than that of the tissue glue or without any treatment. The accomplishment of nerve regeneration and continuity without causing neurotoxicity justifies using DuraSeal as a ligature in the anastomosis of nerve gap injury.

Amniotic fluid mesenchymal stem cells (AFS) harbor the potential to improve peripheral nerve injury by inherited neurotrophic factor secretion, but present the drawback of the short-term survival after transplantation. Granulocyte-colony stimulating factor (G-CSF) has a diversity of functions, including anti-inflammatory and anti-apoptotic effects. This study was conducted to evaluate whether G-CSF could augment the neuroprotective effect of transplanted AFS against peripheral nerve injury. The potential involvement of anti-inflammation/anti-apoptosis effect was also investigated. Peripheral nerve injury was produced in Sprauge-Dawley rats by crushing left sciatic nerve using a vessel clamp. The AFS were embedded in fibrin glue and delivered to the injured site. G-CSF (50 microg/kg) was administrated by intra-peritoneal injection for 7 consecutive days. Cell apoptosis, inflammatory cytokines, motor function, and nerve regeneration were evaluated 7 or 28 days after injury. Crush injury induced inflammatory response, disrupted nerve integrity, and impaired nerve function in sciatic nerve. Crush injury-provoked inflammation was attenuated in groups receiving G-CSF but not in AFS only group. In transplanted AFS, marked apoptosis was detected and this event was reduced by G-CSF treatment. Increased nerve myelination and improved motor function were observed in AFS transplanted, G-CSF administrated, and AFS/G-CSF combined treatment groups. Significantly, the combined treatment showed the most beneficial effect. In conclusion, the concomitant treatment of AFS with G-CSF augments peripheral nerve regeneration which may involve the suppression of apoptotic death in implanted AFS and the attenuation of inflammatory response.

We tested the herbal extract 2,3,5,6-tetramethylpyrazine (TMP) for possible therapeutic efficacy against a glioma cell line and against gliomas transplanted into rat brains. In the cultured glioma cells, 50 muM TMP significantly inhibited glutamate-induced increase in intracellular calcium. Significant cell damage (30%) and proliferation suppression (10%), however, occurred only at higher concentrations (200-400 microM). Gliomaneuronal co-culturing resulted in significant neuronal damage and higher proliferation of the glioma cells (140%) compared with single cultures. Low concentrations of TMP (< or =200 microM) attenuated the neuronal damage, suppressed glioma migration, and decreased glioma proliferation in the neuronal-glioma co-culture. Gliomas transplanted into the frontal cortical area exhibited high proliferation, with untreated rats dying 10-23 days later. TMP treatment inhibited tumor growth and significantly extended survival time. The results indicate that TMP can suppress glioma activity, including growth, and protect neurons against glioma-induced excitotoxicity, suggesting that TMP may have therapeutic potential in the treatment of malignant gliomas.

The time window in the treatment of ischemic stroke with tissue plasminogen activator (tPA) is narrow, arbitrarily within 3 hours after the onset of symptom. Hemorrhagic transformation resulting from cerebral ischemia may be related to damage of the microvascular basal lamina of the brain, which may in turn cause microvascular fibrin deposition and aggravate cerebral ischemia. Here, we investigated the effect of tPA on the microvascular tissue changes during cerebral ischemia/reperfusion. Sprague-Dawley rats were subjected to focal cerebral ischemia by ligation of the right middle cerebral artery and bilateral common carotid arteries for 90 minutes. Sixty minutes after the onset of ischemia, escalated dosages of tPA from 2.5 to 10 mg/kg or saline were intravenously infused for 60 minutes. Twenty-four hours after reperfusion, the animals were allowed to be killed for examination. Low dosage of tPA (2.5-7.5 mg/kg) reduced post-ischemic brain infarction, suppressed metalloproteinase 2 (MMP-2) activity and restored blood-brain barrier (BBB) integrity. In contrast, high dose of tPA (10 mg/kg) aggravated brain infarction, increased MMP-2 activity and exacerbated BBB disruption. Cerebral ischemia/reperfusion decreased the immunoreactivity of both collagen type IV- and laminin-positive microvessels, whereas the low dosage of tPA (2.5-7.5 mg/kg) attenuated the reduction. When these molecules in whole cortical tissues were analysed, tPA dosage-dependently decreased the total content of collagen type IV, laminin and fibronectin. Although the detailed mechanisms regarding the action of tPA are yet to be investigated, our findings demonstrate that the detrimental effect of tPA was mediated, at least in part, through the destruction of the basal lamina in the cerebral microvessels by activating MMP-2.

Ginkgo biloba exerts many pharmacological actions. It possesses antioxidant properties, the ability of neurotransmitter/receptor modulation and antiplatelet activation factor. This research is designed to investigate the neuroprotective effects of long-term treatment with EGb761 (a standard form of the extract of Ginkgo biloba leaf) in combination with MgSO 4, FK506, or MK-801 on the infarct volume of male gerbils' brain induced by unilateral middle cerebral artery occlusion (MCAO). Thirty-five gerbils fed a standard diet were intragastrically given water or EGb761 (100 mg/kg/day) for one week. Five randomized groups were established: control ( n = 7), EGb 761 ( n = 8), EGb 761 + MgSO 4 ( n = 7), EGb 761 + FK 506 ( n = 7), and EGb 761 + MK -801 ( n = 6). The three drug-combination groups were injected with MgSO 4 (90 mg/kg), FK506 (0.5 mg/kg), or MK-801 (1 mg/kg), respectively 30 min before MCAO. Gerbils were anesthetized and craniectomized to expose the right middle cerebral artery (MCA). The right MCA was constricted with an 8-0 suture to produce a permanent ligation for 24 hours. Postmortem infarct volumes were determined by quantitative image analysis of 2,3,5-triphenyltetrazolium chloride (TTC)-stained brain sections. Results showed that the total infarct volumes of the four treated groups either EGb761 alone or in combination with drugs were lower than the control group by 36.1% (EGb761 alone), 40.3% ( EGb 761 + MgSO 4), 35.3% ( EGb 761 + FK 506), and 56.4% ( EGb 761 + MK -801), respectively ( p < 0.01). The main affected areas of the brain in the four treated groups were significantly focused between 4 and 6 mm from the frontal pole, when compared to the control group ( p < 0.01). All animals in the five groups had infarctions in both cortex and subcortex. These results indicate that long-term pre-treatment of EGb761 administered either alone or in combination with drugs significantly effective neuroprotection on infarct volume in gerbil ischemic brains.

An in vitro ischemia model (oxygen, glucose, and serum deprivation) is used to investigate the possible cellular and molecular mechanisms responsible for cerebral ischemia. We have previously demonstrated that supernatants derived from ischemic microglia can protect ischemic brain cells by releasing GDNF and TGF-beta1. In the present study, we investigate whether products of ischemic astrocytes can also protect ischemic microglia, astrocytes, and neurons in a similar manner. Supernatants from ischemic astrocytes were collected after various periods of ischemia and incubated with microglia, astrocytes, or neurons individually, under in vitro ischemic conditions. The components responsible for the protective effects of astrocyte-derived supernatants were then identified by Western blot, ELISA, trypan blue dye exclusion, and immunoblocking assays. Results showed that under conditions of in vitro ischemia the number of surviving microglia, astrocytes, and neurons was significantly increased by the incorporation of the astrocyte-derived supernatants. Astrocyte supernatant-mediated protection of ischemic microglia was dependent on TGF-beta1 and NT-3, ischemic astrocytes were protected by GDNF, and ischemic neurons were protected by NT-3. In addition, protein expression of TGF-beta1 and NT-3 receptors in microglia, GDNF receptors in astrocytes, and NT-3 receptors in neurons was increased by in vitro ischemia. These results suggest that astrocyte-derived protection of ischemic brain cells is dependent not only on factors released from the ischemic astrocytes, but also on the type of receptor present on the responding cells. Therapeutic potential of TGF-beta1, GDNF, and NT-3 in the control of cerebral ischemia is further suggested.

Flame atomic absorption spectrometry (FAAS) and a microdialysis analyzer were employed for dynamic monitoring of magnesium (Mg), glucose and lactate levels in blood samples of gerbils subjected to cerebral ischemia.Focal cerebral ischemia was induced by occlusion of the unilateral common carotid artery and the middle cerebral artery for 60 minutes followed by 180 minutes of reperfusion. Whole blood samples were continuously collected from the jugular vein via an auto-blood sampling system. The dynamic profiles of Mg, glucose and lactate before, during and after ischemia were determined.During cerebral ischemia, blood Mg levels gradually rose to 130% of the baseline and returned to the basal levels within 30 minutes after reperfusion. Lactate concentrations decreased to approximately 50% of the basal levels during cerebral ischemia and returned to basal levels immediately after reperfusion. Glucose levels remained the same during cerebral ischemia and gradually fell to 50% of basal levels at the end of reperfusion. The linearity ranges of glucose, lactate and Mg were 0.1-25 mM, 0.02-2.5 mM and 5-1500 microg/L, respectively. The required volume of each blood sample is less than 30 microL. The intra- and inter-assay variation was less than 3%. Since blood loss is minimal from repeated blood sampling, it is suitable for small animals.Mg may be accumulated in blood cells, which are helpful for reducing glucose utilization. As a result, less lactate was produced during the acute phase of cerebral ischemia. Preservation of glucose is advantageous for brain cells' restoration after ischemia.

Description of use of equipment for on-line microdialysis (MD) coupled with graphite furnace atomic absorption spectrometry (GFAAS) system, for dynamic monitoring of extracellular Mg in gerbils subjected to transient focal cerebral ischemia.Gerbils' right middle cerebral artery (MCA) and common carotid artery (CCA) were occluded for 60 minutes, and then reperfused for 60 minutes with Ringer's solution, after which extracellular fluid samples were collected via a microdialysis probe inserted into the right cortex before, during and after inducing ischemia. Reperfusion was at a rate of 2 microL/min through the microdialysis probe, on-line diluted with measured water injected onto the GFAAS via an autosampler for Mg analysis.The detection limit of the Mg concentrations has ranged from 0.50 to 3.00 microg/L; our detection limit was 0.03 microg/L. We applied this on-line system to monitor extracellular Mg levels in the cortex during focal cerebral ischemia. Mg concentrations significantly decreased to 41% of baseline during cerebral ischemia and gradually returned to 67% of baseline after 60 minutes of reperfusion.We presume that derangement of Mg homeostasis could be important in brain cell injury and is closely associated with cerebral ischemia event. The described analytic system permits autosampling in the brain and allows for continuous determination of Mg and trace minerals in minute sample volumes in a living system.