Neuroinflammation, Stem Cells, and Stroke.

Stroke remains a significant unmet clinical need with few treatment options that have a very narrow therapeutic window, thereby causing massive mortality and morbidity in the United States and around the world. Accordingly, finding safe and effective novel treatments with a wider therapeutic window stands as an urgent need in stroke. The progressive inflammation that occurs centrally and peripherally after stroke serves as a unique therapeutic target to retard and even halt the secondary cell death. Stem cell therapy represents a potent approach that can diminish inflammation in both the stroke brain and periphery (eg, spleen), advancing a paradigm shift from a traditionally brain-focused therapy to treating stroke as a neurological disorder with a significant peripheral pathology. The purpose of this review article is to highlight the inflammation-mediated secondary cell death that plagues both brain and spleen in stroke and to evaluate the therapeutic potential of stem cell therapy in dampening these inflammatory responses.

Sequestration of Inflammation in Parkinson's Disease via Stem Cell Therapy.

Parkinson's disease is the second most common neurodegenerative disease. Insidious and progressive, this disorder is secondary to the gradual loss of dopaminergic signaling and worsening neuroinflammation, affecting patients' motor capabilities. Gold standard treatment includes exogenous dopamine therapy in the form of levodopa-carbidopa, or surgical intervention with a deep brain stimulator to the subcortical basal ganglia. Unfortunately, these therapies may ironically exacerbate the already pro-inflammatory environment. An alternative approach may involve cell-based therapies. Cell-based therapies, whether endogenous or exogenous, often have anti-inflammatory properties. Alternative strategies, such as exercise and diet modifications, also appear to play a significant role in facilitating endogenous and exogenous stem cells to induce an anti-inflammatory response, and thus are of unique interest to neuroinflammatory conditions including Parkinson's disease. Treating patients with current gold standard therapeutics and adding adjuvant stem cell therapy, alongside the aforementioned lifestyle modifications, may ideally sequester inflammation and thus halt neurodegeneration.

Cell encapsulation enhances antidepressant effect of the mesenchymal stem cells and counteracts depressive-like behavior of treatment-resistant depressed rats.

Despite the advances in pharmacological therapies, only the half of depressed patients respond to currently available treatment. Thus, the need for further investigation and development of effective therapies, especially those designed for treatment-resistant depression, has been sorely needed. Although antidepressant effects of mesenchymal stem cells (MSCs) have been reported, the potential benefit of this cell therapy on treatment-resistant depression is unknown. Cell encapsulation may enhance the survival rate of grafted cells, but the therapeutic effects and mechanisms mediating encapsulation of MSCs remain unexplored. Here, we showed that encapsulation enhanced the antidepressant effects of MSCs by attenuating depressive-like behavior of Wistar Kyoto (WKY) rats, which are considered as a promising animal model of treatment-resistant depression. The implantation of encapsulated MSCs (eMSCs) into the lateral ventricle counteracted depressive-like behavior and enhanced the endogenous neurogenesis in the subventricular zone (SVZ) and the dentate gyrus (DG) of the hippocampus, whereas the implantation of MSCs without encapsulation or the implantation of eMSCs into the striatum did not show such ameliorative effects. eMSCs displayed robust and stable secretion of vascular endothelial growth factor (VEGF), brain-derived neurotrophic factor, fibroblast growth factor-2, and ciliary neurotrophic factor (CNTF), and the implantation of eMSCs into the lateral ventricle activated relevant pathways associated with these growth factors. Additionally, eMSCs upregulated intrinsic expression of VEGF and CNTF and their receptors. This study suggests that the implantation of eMSCs into the lateral ventricle exerted antidepressant effects likely acting via neurogenic pathways, supporting their utility for depression treatment.

Semi-automated measurement of vascular tortuosity and its implications for mechanical thrombectomy performance.

PURPOSE: Few studies have examined the geometry of endovascular mechanical thrombectomy pathways. Here we examine the tortuosity and angulations of catheter pathways from the aortic arch to the termination of the internal carotid artery (ICA) and its association with thrombectomy performance. METHODS: We included 100 consecutive anterior circulation large vessel occlusion thrombectomy patients over 12 months. Computed tomography angiograms (CTA) were used for 3D segmentation of catheter pathway from the aortic arch to ICA termination. Tortuosity index (TI) and angulations of the catheter pathway were measured in a semi-automated fashion. TI and angulation degree were compared between sides and correlated with age and procedural measures. RESULTS: We analyzed 188 catheter pathways in 100 patients. Severe angulation (≤ 30°) was present in 5.8% and 39.4% of common carotid artery (CCA) and extracranial ICA segments, respectively. Five pathways (2.6%) had 360° loop. CCA and extracranial ICA tortuosity had a weak but significant correlation with age (r = 0.17, 0.21, p value = 0.05, 0.02 respectively), time from groin puncture to the site of occlusion (r = 0.29, 0.25, p values = 0.008, 0.026 respectively), and fluoroscopy time (r = 0.022, 0.31, p values = 0.016, 0.001 respectively). There was a significant difference in the pattern of angulation (p value = 0.04) and tortuosity between right and left side in CCA segment (TI = 0.20 ± 0.086 vs. 0.15 ± 0.82, p value < 0.001). CONCLUSIONS: There was a significant difference in CCA angulation between right and left sides. TI of extracranial CCA and ICA correlated with age and influenced time from groin puncture to the occlusion site and total fluoroscopy time.

Gutting the brain of inflammation: A key role of gut microbiome in human umbilical cord blood plasma therapy in Parkinson's disease model.

Current therapies for Parkinson's disease (PD), including L-3,4-dihydroxyphenylalanine (L-DOPA), and clinical trials investigating dopaminergic cell transplants, have generated mixed results with the eventual induction of dyskinetic side effects. Although human umbilical cord blood (hUCB) stem/progenitor cells present with no or minimal capacity of differentiation into mature dopaminergic neurons, their transplantation significantly attenuates parkinsonian symptoms likely via bystander effects, specifically stem cell graft-mediated secretion of growth factors, anti-inflammatory cytokines, or synaptic function altogether promoting brain repair. Recognizing this non-cell replacement mechanism, we examined here the effects of intravenously transplanted combination of hUCB-derived plasma into the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced rat model of PD. Animals received repeated dosing of either hUCB-derived plasma or vehicle at 3, 5 and 10 days after induction into MPTP lesion, then behaviourally and immunohistochemically evaluated over 56 days post-lesion. Compared to vehicle treatment, transplantation with hUCB-derived plasma significantly improved motor function, gut motility and dopaminergic neuronal survival in the substantia nigra pars compacta (SNpc), which coincided with reduced pro-inflammatory cytokines in both the SNpc and the intestinal mucosa and dampened inflammation-associated gut microbiota. These novel data directly implicate a key pathological crosstalk between gut and brain ushering a new avenue of therapeutically targeting the gut microbiome with hUCB-derived stem cells and plasma for PD.

Comparing the effect of the novel ionic cocrystal of lithium salicylate proline (LISPRO) with lithium carbonate and lithium salicylate on memory and behavior in female APPswe/PS1dE9 Alzheimer's mice.

Alzheimer's disease (AD) is characterized by progressive decline of cognition and associated neuropsychiatric signs including weight loss, anxiety, depression, agitation, and aggression, which is particularly pronounced in the female gender. Previously, we have shown that a novel ionic co-crystal of lithium salicylate proline (LISPRO) is an improved lithium formulation compared to the carbonate or salicylate form of lithium in terms of safety and efficacy in reducing AD pathology in Alzheimer's mice. The current study is designed to compare the prophylactic effects of LISPRO, lithium carbonate (LC), and lithium salicylate (LS) on cognitive and noncognitive impairments in female transgenic APPswe/PS1dE9 AD mice. Female APPswe/PS1dE9 mice at 4 months of age were orally treated with low-dose LISPRO, LS, or LC for 9 months at 2.25 mmol lithium/kg/day followed by determination of body weight, growth of internal organs, and cognitive and noncognitive behavior. No significant differences in body or internal organ weight, anxiety or locomotor activity were found between lithium treated and untreated APPswe/PS1dE9 cohorts. LISPRO, LC, and LS prevented spatial cognitive decline, as determined by Morris water maze and depression as determined by tail suspension test. In addition, LISPRO treatment was superior in preventing associative memory decline determined by contextual fear conditioning and reducing irritability determined by touch escape test in comparison with LC and LS. In conclusion, low-dose LISPRO, LC, and LS treatment prevent spatial cognitive decline and depression-like behavior, while LISPRO prevented hippocampal-dependent associative memory decline and irritability in APPswe/PS1dE9 mice.

Human stem cells transplanted into the rat stroke brain migrate to the spleen via lymphatic and inflammation pathways.

Despite mounting evidence of a massive peripheral inflammatory response accompanying stroke, the ability of intracerebrally transplanted cells to migrate to the periphery and sequester systemic inflammation remains unexamined. Here, we tested the hypothesis that human bone marrow mesenchymal stromal cells intracerebrally transplanted in the brain of adult rats subjected to experimental stroke can migrate to the spleen, a vital organ that confers peripheral inflammation after stroke. Sham or experimental stroke was induced in adult Sprague-Dawley rats by a 1 hour middle cerebral artery occlusion model. One hour after surgery, rats were intracerebrally injected with human bone marrow mesenchymal stromal cells (3×105/9 µL), then euthanized on day 1, 3, or 7 for immunohistochemical assays. Cell migration assays were performed for human bone marrow mesenchymal stromal cells using Boyden chambers with the bottom plate consisting of microglia, lymphatic endothelial cells, or both, and treated with different doses of tumor necrosis factor-α. Plates were processed in a fluorescence reader at different time points. Immunofluorescence microscopy on different days after the stroke revealed that stem cells engrafted in the stroke brain but, interestingly, homed to the spleen via lymphatic vessels, and were propelled by inflammatory signals. Experiments using human bone marrow mesenchymal stromal cells co-cultured with lymphatic endothelial cells or microglia, and treated with tumor necrosis factor-α, further indicated the key roles of the lymphatic system and inflammation in directing stem cell migration. This study is the first to demonstrate brain-to-periphery migration of stem cells, advancing the novel concept of harnessing the lymphatic system in mobilizing stem cells to sequester peripheral inflammation as a brain repair strategy.

Reduced Cholinergic Activity in the Hippocampus of Hippocampal Cholinergic Neurostimulating Peptide Precursor Protein Knockout Mice.

The cholinergic efferent network from the medial septal nucleus to the hippocampus has an important role in learning and memory processes. This cholinergic projection can generate theta oscillations in the hippocampus to efficiently encode novel information. Hippocampal cholinergic neurostimulating peptide (HCNP) induces acetylcholine synthesis in medial septal nuclei. HCNP is processed from the N-terminal region of a 186 amino acid, 21 kD HCNP precursor protein called HCNP-pp (also known as Raf kinase inhibitory protein (RKIP) and phosphatidylethanolamine-binding protein 1 (PEBP1)). In this study, we generated HCNP-pp knockout (KO) mice and assessed their cholinergic septo-hippocampal projection, local field potentials in CA1, and behavioral phenotypes. No significant behavioral phenotype was observed in HCNP-pp KO mice. However, theta power in the CA1 of HCNP-pp KO mice was significantly reduced because of fewer cholineacetyltransferase-positive axons in the CA1 stratum oriens. These observations indicated disruption of cholinergic activity in the septo-hippocampal network. Our study demonstrates that HCNP may be a cholinergic regulator in the septo-hippocampal network.

Pituitary Adenylate Cyclase Activating Polypeptide Elicits Neuroprotection Against Acute Ischemic Neuronal Cell Death Associated with NMDA Receptors.

BACKGROUND/AIMS: The endogenous neurotrophic peptides pituitary adenylate cyclase-activating polypeptides (PACAP-27/38) protect against stroke, but the molecular mechanism remains unknown. METHODS: Primary rat neural cells were exposed to PACAP-27 or PACAP-38 before induction of experimental acute ischemic stroke via oxygen-glucose deprivation-reperfusion (OGD/R) injury. To reveal PACAP's role in neuroprotection, we employed fluorescent live/dead cell viability and caspase 3 assays, optical densitometry of mitochondrial dehydrogenase and cell growth, glutathione disulfide luciferase activity, ELISA for high mobility group box1 extracellular concentration, ATP bioluminescence, Western blot analysis of PACAP, NMDA subunits, apoptosis regulator Bcl-2, social interaction hormone oxytocin, and trophic factor BDNF, and immunocytochemical analysis of PACAP. RESULTS: Both PACAP-27 and PACAP-38 (PACAP-27/38) increased cell viability, decreased oxidative stress-induced cell damage, maintained mitochondrial activity, prevented the release of high mobility group box1, and reduced cytochrome c/caspase 3-induced apoptosis. PACAP-27/38 increased the protein expression levels of BDNF, Bcl-2, oxytocin, and precursor PACAP. N-methyl-D-aspartate receptor (NMDAR)-induced excitotoxicity contributes to the cell death associated with stroke. PACAP-27/38 modulated the protein expression levels of NMDAR subunits. PACAP-27/38 increased the protein expression levels of the GluN1 subunit, and decreased that of the GluN2B and GluN2D subunits. PACAP-27, but not PACAP-38, increased the expression level of the GluN2C subunit. CONCLUSION: This study provides evidence that PACAP regulated NMDAR subunits, affording neuroprotection after OGD/R injury.

Electrical Stimulation Enhances Migratory Ability of Transplanted Bone Marrow Stromal Cells in a Rodent Ischemic Stroke Model.

BACKGROUND/AIMS: Bone marrow stromal cells (BMSCs) transplantation is an important strategy for the treatment of ischemic stroke. Currently, there are no effective methods to guide BMSCs toward the targeted site. In this study, we investigated the effect of electrical stimulation on BMSCs migration in an ischemic model of rats. METHODS: Adult male Wistar rats weighing 200 to 250 g received right middle cerebral artery occlusion (MCAO) for 90 minutes. BMSCs (2.5×105 cells/ 4 µl PBS) were stereotaxically injected into the left corpus callosum at 1 day after MCAO. After BMSCs injection, a plate electrode with a diameter of 3 mm connected to an implantable electrical stimulator was placed on the right frontal epidural space and a counter electrode was placed in the extra-cranial space. Electrical stimulation at preset current (100 µA) and frequency (100 Hz) was performed for two weeks. Behavioral tests were performed at 1, 4, 8, and 15 days after MCAO using the modified Neurological Severity Score (mNSS) and cylinder test. Rats were euthanized at 15 days after MCAO for evaluation of infarction area and the migration distance and area of BMSCs found in the brain tissue. After evaluating cell migration, we proceeded to explore the mechanisms guiding these observations. MCAO rats without BMSCs transplantation were stimulated with same current and frequency. At 1 and 2 weeks after MCAO, rats were euthanized to evaluate stromal cell-derived factor 1 alpha (SDF-1α) level of brain tissues in the bilateral cortex and striatum. RESULTS: Behavioral tests at 4, 8, and 15 days after MCAO revealed that stimulation group displayed significant amelioration in mNSS and cylinder test compared to control group (p<0.05). Similarly, the infarction areas of stroke rats in stimulation group were significantly decreased compared to control group (p<0.05). Migration distance and area of transplanted BMSCs were significantly longer and wider respectively in stimulation group. An increased concentration gradient of SDF-1α in stimulation group accompanied this enhanced migration of transplanted cells. CONCLUSIONS: These results suggest that electrical stimulation enhances migratory ability of transplanted BMSCs in ischemic stroke model of rats. If we can direct the implanted BMSCs to the site of interest, it may lead to a greater therapeutic effect.

Long noncoding RNA MALAT1 in exosomes drives regenerative function and modulates inflammation-linked networks following traumatic brain injury.

BACKGROUND: Neuroinflammation is a common therapeutic target for traumatic brain injury (TBI) due to its contribution to delayed secondary cell death and has the potential to occur for years after the initial insult. Exosomes from adipose-derived stem cells (hASCs) containing the long noncoding RNA MALAT1 are a novel, cell-free regenerative approach to long-term recovery after traumatic brain injury (TBI) that have the potential to modulate inflammation at the genomic level. The long noncoding RNA MALAT1 has been shown to be an important component of the secretome of hASCs. METHODS: We isolated exosomes from hASC containing or depleted of MALAT1. The hASC-derived exosomes were then administered intravenously to rats following a mild controlled cortical impact (CCI). We followed the rats with behavior, in vivo imaging, histology, and RNA sequencing (RNA Seq). RESULTS: Using in vivo imaging, we show that exosomes migrate into the spleen within 1 h following administration and enter the brain several hours later following TBI. Significant recovery of function on motor behavior as well as a reduction in cortical brain injury was observed after TBI in rats treated with exosomes. Treatment with either exosomes depleted of MALAT1 or conditioned media depleted of exosomes showed limited regenerative effects, demonstrating the importance of MALAT1 in exosome-mediated recovery. Analysis of the brain and spleen transcriptome using RNA Seq showed MALAT1-dependent modulation of inflammation-related pathways, cell cycle, cell death, and regenerative molecular pathways. Importantly, our data demonstrates that MALAT1 regulates expression of other noncoding RNAs including snoRNAs. CONCLUSION: We demonstrate that MALAT1 in hASC-derived exosomes modulates multiple therapeutic targets, including inflammation, and has tremendous therapeutic potential for treatment of TBI.

Intravenously Transplanted Human Bone Marrow Endothelial Progenitor Cells Engraft Within Brain Capillaries, Preserve Mitochondrial Morphology, and Display Pinocytotic Activity Toward Blood-Brain Barrier Repair in Ischemic Stroke Rats.

Stroke is a life-threatening disease with limited therapeutic options. Cell therapy has emerged as an experimental stroke treatment. Blood-brain barrier (BBB) impairment is a key pathological manifestation of ischemic stroke, and barrier repair is an innovative target for neurorestoration in stroke. Here, we evaluated via electron microscopy the ability of transplanted human bone marrow endothelial progenitor cells (hBMEPCs) to repair the BBB in adult Sprague-Dawley rats subjected to transient middle cerebral artery occlusion (tMCAO). ß-galactosidase prelabeled hBMEPCs were intravenously transplanted 48 hours post-tMCAO. Ultrastructural analysis of microvessels in nontransplant stroke rats revealed typical BBB pathology. At 5 days post-transplantation with hBMEPCs, stroke rats displayed widespread vascular repair in bilateral striatum and motor cortex, characterized by robust cell engraftment within capillaries. hBMEPC transplanted stroke rats exhibited near normal morphology of endothelial cells (ECs), pericytes, and astrocytes, without detectable perivascular edema. Near normal morphology of mitochondria was also detected in ECs and perivascular astrocytes from transplanted stroke rats. Equally notable, we observed numerous pinocytic vesicles within engrafted cells. Robust engraftment and intricate functionality of transplanted hBMEPCs likely abrogated stroke-altered vasculature. Preserving mitochondria and augmenting pinocytosis in cell-based therapeutics represent a new neurorestorative mechanism in BBB repair for stroke. Stem Cells 2017;35:1246-1258.

Potential Role of Humoral IL-6 Cytokine in Mediating Pro-Inflammatory Endothelial Cell Response in Amyotrophic Lateral Sclerosis.

Amyotrophic lateral sclerosis (ALS) is a multifactorial disease with limited therapeutic options. Numerous intrinsic and extrinsic factors are involved in ALS motor neuron degeneration. One possible effector accelerating motor neuron death in ALS is damage to the blood-Central Nervous System barrier (B-CNS-B), mainly due to endothelial cell (EC) degeneration. Although mechanisms of EC damage in ALS are still unknown, vascular impairment may be initiated by various humoral inflammatory factors and other mediators. Systemic IL-6-mediated inflammation is a possible early extrinsic effector leading to the EC death causing central nervous system (CNS) barrier damage. In this review, we discuss the potential role of humoral factors in triggering EC alterations in ALS. A specific focus was on humoral IL-6 cytokine mediating EC inflammation via the trans-signaling pathway. Our preliminary in vitro studies demonstrated a proof of principle that short term exposure of human bone marrow endothelial cells to plasma from ALS patient leads to cell morphological changes, significantly upregulated IL-6R immunoexpression, and pro-inflammatory cell response. Our in-depth understanding of specific molecular mechanisms of this humoral cytokine in EC degeneration may facilitate an endothelial-IL-6-targeting therapy for restoring cell homeostasis and eventually reestablishing B-CNS-B integrity in ALS.

Human Muse Cells Reconstruct Neuronal Circuitry in Subacute Lacunar Stroke Model.

BACKGROUND AND PURPOSE: Multilineage-differentiating stress-enduring (muse) cells are endogenous nontumorigenic stem cells with pluripotency harvestable as pluripotent marker SSEA-3+ cells from the bone marrow from cultured bone marrow-mesenchymal stem cells. After transplantation into neurological disease models, muse cells exert repair effects, but the exact mechanism remains inconclusive. METHODS: We conducted mechanism-based experiments by transplanting serum/xeno-free cultured-human bone marrow-muse cells into the perilesion brain at 2 weeks after lacunar infarction in immunodeficient mice. RESULTS: Approximately 28% of initially transplanted muse cells remained in the host brain at 8 weeks, spontaneously differentiated into cells expressing NeuN (≈62%), MAP2 (≈30%), and GST-pi (≈12%). Dextran tracing revealed connections between host neurons and muse cells at the lesioned motor cortex and the anterior horn. Muse cells extended neurites through the ipsilateral pyramidal tract, crossed to contralateral side, and reached to the pyramidal tract in the dorsal funiculus of spinal cord. Muse-transplanted stroke mice displayed significant recovery in cylinder tests, which was reverted by the human-selective diphtheria toxin. At 10 months post-transplantation, human-specific Alu sequence was detected only in the brain but not in other organs, with no evidence of tumor formation. CONCLUSIONS: Transplantation at the delayed subacute phase showed muse cells differentiated into neural cells, facilitated neural reconstruction, improved functions, and displayed solid safety outcomes over prolonged graft maturation period, indicating their therapeutic potential for lacunar stroke.

Transplantation of Unique Subpopulation of Fibroblasts, Muse Cells, Ameliorates Experimental Stroke Possibly via Robust Neuronal Differentiation.

OBJECTIVE: Muse cells reside as pre-existing pluripotent-like stem cells within the fibroblasts, are nontumorigenic, exhibit differentiation capacity into triploblastic-lineage cells, and replenish lost cells when transplanted in injury models. Cell fate and function of human skin fibroblast-derived Muse cells were evaluated in a rat stroke model. METHODS: Muse cells (30,000), collected by pluripotent surface marker stage-specific embryonic antigen-3, were injected stereotaxically into three deposits within the rat ischemic cortex at 2 days after transient middle cerebral artery occlusion, and the cells' biological effects were examined for more than 84 days. RESULTS: Muse cells spontaneously and promptly committed to neural/neuronal-lineage cells when cocultured with stroke brain slices. Muse-transplanted stroke rats exhibited significant improvements in neurological and motor functions compared to control groups at chronic days 70 and 84, without a reduction in the infarct size. Muse cells survived in the host brain for up to 84 days and differentiated into NeuN (∼ 65%), MAP-2 (∼ 32%), calbindin (∼ 28%), and GST-π (∼ 25%)-positive cells in the cortex, but glial fibrillary acidic protein-positive cells were rare. Tumor formation was not observed. Muse cells integrated into the sensory-motor cortex, extended their neurites into cervical spinal cord, and displayed normalized hind limb somatosensory evoked potentials. INTERPRETATION: Muse cells are unique from other stem cells in that they differentiate with high ratio into neuronal cells after integration with host brain microenvironment, possibly reconstructing the neuronal circuit to mitigate stroke symptoms. Human fibroblast-derived Muse cells pose as a novel source of transplantable stem cells, circumventing the need for gene manipulations, especially when contemplating autologous cell therapy for stroke.

Peripheral Nerve Injury: Stem Cell Therapy and Peripheral Nerve Transfer.

Peripheral nerve injury can lead to great morbidity in those afflicted, ranging from sensory loss, motor loss, chronic pain, or a combination of deficits. Over time, research has investigated neuronal molecular mechanisms implicated in nerve damage, classified nerve injury, and developed surgical techniques for treatment. Despite these advancements, full functional recovery remains less than ideal. In this review, we discuss historical aspects of peripheral nerve injury and introduce nerve transfer as a therapeutic option, as well as an adjunct therapy to transplantation of Schwann cells and their stem cell derivatives for repair of the damaged nerve. This review furthermore, will provide an elaborated discussion on the sources of Schwann cells, including sites to harvest their progenitor and stem cell lines. This reflects the accessibility to an additional, concurrent treatment approach with nerve transfers that, predicated on related research, may increase the efficacy of the current approach. We then discuss the experimental and clinical investigations of both Schwann cells and nerve transfer that are underway. Lastly, we provide the necessary consideration that these two lines of therapeutic approaches should not be exclusive, but conversely, should be pursued as a combined modality given their mutual role in peripheral nerve regeneration.

Nickel free-diet enhances the Helicobacter pylori eradication rate: a pilot study.

BACKGROUND: The Helicobacter pylori eradication rate with standard triple therapy is very low. H. pylori is known to require the nickel-containing metalloenzymes urease and NiFe-hydrogenase to survive at the low pH environment in the stomach. AIM: To compare the H. pylori eradication rate of a nickel free-diet associated with standard triple therapy and standard triple therapy alone as the first-line regimen. METHODS: Fifty-two sex- and age-matched patients at the first diagnosis of H. pylori infection were randomized 1:1 into two different therapeutic schemes: (1) standard LCA (26 patients): lansoprazole 15 mg bid, clarithromycin 500 mg bid and amoxicillin 1,000 mg bid for 7 days with a common diet; (2) standard LCA plus a nickel free-diet (NFD-LCA) (26 patients). Patients followed 30 days of a nickel-free diet plus a week of lansoprazole 15 mg bid, clarithromycin 500 mg bid and amoxicillin 1,000 mg bid starting from day 15 of the diet. RESULTS: All patients completed the study. A significantly higher eradication rate was observed in the NFD-LCA group (22/26) versus LCA group (12/26) (p < 0.01). Only a few patients (9 of 52) reported the occurrence of mild therapy-related side effects, without any significant differences between the two groups. CONCLUSIONS: The addition of a nickel-free diet to standard triple therapy significantly increases the H. pylori eradication rate. The reduction of H. pylori urease activity due to the nickel-free diet could expose the bacterium to gastric acid and increase H. pylori's susceptibility to amoxicillin. Further studies are necessary to confirm this preliminary result.

Methane intestinal production and poor metabolic control in type I diabetes complicated by autonomic neuropathy.

AIM: At the state of art it's unknown the correlation between diabetes and lower gastrointestinal disorders. Some studies show a significantly higher prevalence of small intestinal bacterial overgrowth in patients with type I diabetes in particular complicated by autonomic neuropathy. No data exists about gastrointestinal methane production in patients with diabetes and autonomic diabetic neuropathy. The aim of this paper was to evaluate the correlation of small intestinal bacterial overgrowth and gastrointestinal methane production with metabolic control and daily insulin requirements in patients with type 1 diabetes and. autonomic diabetic neuropathy. METHODS: Thirty subjects with type 1 diabetes and autonomic diabetic neuropathy were underwent hydrogen and methane lactulose breath test (LBT) to evaluate the presence of small intestinal bacterial overgrowth (double peak of hydrogen) and methane production. The metabolic control was evaluated through the glycated hemoglobin and the daily insulin requirement (calculated as ratio between total insulin units in a day and body weight). Methane producers were treated with metronidazole (500 mg bid for 10 days) and perform a LBT 8 weeks after the end of therapy RESULTS: Eight over thirty patients (26.6%) met the diagnostic criteria for small intestinal bacterial overgrowth. 11/30 patients (36%) were methane-producers (mean baseline value 16.37 ± 13.01 ppm; mean peak 26.62 ± 11.41 ppm); interestingly this subset of patients showed a worse glycemic control (mean HbA1c 8.16 ± 0.9% vs. 7.49 ± 0.8%, P<0.05). After metronidazole therapy 7/11 (63.3%) reduced CH4 production and they showed a mean HbA1c significantly lower than corresponding value before antibiotic therapy (7.63 ± 0.7% vs. 8.25 ± 0.8%). CONCLUSION: Our study showed for the first time a possible role of CH4 production in metabolic control. In particular, the most interesting data is that an increased values of HbA1c seems to be related to a gut CH4 production as confirmed by its significant improvement after eradication therapy. We are not yet able to determine whether poor glycemic control is the cause or the consequence of the selection of methanogenic flora.

Cellular and Noncellular Approaches for Repairing the Damaged Blood-CNS-Barrier in Amyotrophic Lateral Sclerosis.

Numerous reports have demonstrated the breakdown of the blood-CNS barrier (B-CNS-B) in amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease. Re-establishing barrier integrity in the CNS is critical to prevent further motor neuron degeneration from harmful components in systemic circulation. Potential therapeutic strategies for repairing the B-CNS-B may be achieved by the replacement of damaged endothelial cells (ECs) via stem cell administration or enhancement of endogenous EC survival through the delivery of bioactive particles secreted by stem cells. These cellular and noncellular approaches are thoroughly discussed in the present review. Specific attention is given to certain stem cell types for EC replacement. Also, various nanoparticles secreted by stem cells as well as other biomolecules are elucidated as promising agents for endogenous EC repair. Although the noted in vitro and in vivo studies show the feasibility of the proposed therapeutic approaches to the repair of the B-CNS-B in ALS, further investigation is needed prior to clinical transition.

Laterality of cervical disc herniation.

PURPOSE: Cervical disc herniation (CDH) is found more frequently at the lower cervical spine than at the upper or middle level. However, there is scarcity of data about the laterality of CDH. The aim of this study is to detect the laterality of CDH. METHODS: We retrospectively evaluated preoperative computed tomography myelograms and magnetic resonance images of 75 cases of CDH who underwent single level anterior cervical discectomy and fusion at C4-5, C5-6, or C6-7 levels from 2008 to 2010 in our institute. Statistical analyses were performed using the Chi-square test. RESULTS: Eleven cases were found at C4-5 level, 42 cases at C5-6 level, and 22 cases at C6-7 level. At C4-5 level, CDH was recognized at the right side in 2 cases, at the left side in 2 cases, and at the center in 7 cases. At C5-6 level, CDH was found at the right side in 20 cases and at the left side in 22 cases. At C6-7 level, CDH was found at the right side in 3 cases and at the left side in 19 cases with significantly high frequency of left-sided CDH (p < 0.025). CONCLUSIONS: In this study, it was revealed that the left-sided CDH was more frequent than the right-sided CDH at C6-7 level.