Kv4.3 channel downregulation mediates chronic post-lesional pacemaker acceleration in surviving dopamine substantia nigra neurons

Substantia nigra dopamine (SN DA) neurons are progressively lost in Parkinson disease (PD). While the molecular and cellular mechanisms of their differential vulnerability and degeneration have been extensively studied, we still know very little about potential functional adaptations of those SN DA neurons that at least for some time manage to survive during earlier stages of PD. We utilized a partial lesion 6-OHDA mouse model to characterize initial electrophysiological impairments and chronic adaptations of surviving identified SN DA neurons, both in vivo and in vitro. Early after lesion (3 weeks), we detected a selective loss of in vivo burst firing in surviving SN DA neurons, which was accompanied by in vitro pacemaker instability. In contrast, late after lesion (>2 months), in vivo firing properties of surviving SN DA neurons had recovered in the presence of 2-fold accelerated pacemaking in vitro. Finally, we show that this chronic cell-autonomous adaptation in surviving SN DA neurons was mediated by Kv4.3 channel downregulation. Our study demonstrates substantial homeostatic plasticity of surviving SN DA neurons after a single-hit non-progressive lesion, which might contribute to the phenotype of initially surviving SN DA neurons in PD.

Multiple sclerosis: structural and functional integrity of the visual system following alemtuzumab therapy

ObjectiveTo investigate potential neuroprotective and pro-remyelinating effects of alemtuzumab in multiple sclerosis (MS), using the visual pathway as a model.MethodsWe monitored clinical, multifocal visual evoked potential (mfVEP) and MRI outcomes in 30 patients commencing alemtuzumab for relapsing MS, and a reference group of 20 healthy controls (HCs), over 24 months. Change in mfVEP latency was the primary endpoint; change in optic radiation (OR) lesion diffusion metrics and Mars letter contrast sensitivity over the course of the study were secondary endpoints.ResultsIn patients, we observed a mean shortening of mfVEP latency of 1.21 ms over the course of the study (95% CI 0.21 to 2.21, p=0.013), not altered by correction for age, gender, disease duration or change in OR T2 lesion volume. Mean mfVEP latency in the HC group increased over the course of the study by 0.72 ms (not significant). Analysis of chronic OR T2 lesions (patients) showed an increase in normalised fractional anisotropy and axial diffusivity between baseline and 24 months (both p<0.01). Mean Mars letter contrast sensitivity was improved at 24 months vs baseline (p<0.001), and driven by an early improvement, in both patients and HC.ConclusionWe found evidence of partial lesion remyelination after alemtuzumab therapy, indicating either natural restoration in the context of a ‘permissive’ local milieu; or potentially an independent, pro-reparative mechanism of action. The visual system presents a unique opportunity to study function-structure specific effects of therapy and inform the design of future phase 2 MS remyelination trials.

An In Vitro Partial Lesion Model of Differentiated Human Mesencephalic Neurons: Effect of Pericyte Secretome on Phenotypic Markers

Parkinson’s disease (PD) is characterised by the progressive degeneration of dopaminergic (DA) neurons in the substantia nigra pars compacta. Post-mortem data suggests that the loss of DA markers may long precede the cell death, leaving a window to rescue the DA phenotype. Screening for potential neuroprotective or restorative therapies, however, requires that partial lesions of DA neurons can be modelled in vitro. In order to establish a partial lesion model of DA neurons in vitro, we evaluated the effects of different exposure times to 1-methyl-4-phenylpyridinium (MPP+) and 6-hydroxydopamine (6-OHDA) on the cell survival and DA marker expression using DA neurons derived from the Lund human mesencephalic (LUHMES) cell line. We show that 24-h incubation with 50 μM of MPP+ or 6-h incubation with 100 μM of 6-OHDA leads to a significant decrease in the protein expression of DA markers without affecting overall cell death, consistent with a mild DA lesion. Using conditioned medium of human brain–derived pericytes stimulated with platelet-derived growth factor BB (PDGF-BB), we demonstrate a significant upregulation of DA markers. In conclusion, we provide an experimental model of an in vitro DA neuron partial lesion suitable to study different molecules and their potential neuroprotective or neurorestorative effects on the DA phenotype. We provide evidence that the secretome of brain pericytes stimulated via PDGF-BB/PDGFRβ affects DA marker expression and may represent one possible mechanism contributing to the neurorestoration previously observed in PD by this growth factor.

Season, Weather, Arthritis, Dermatitis, and Cardiovascular Abnormalities – Systemic Diseases Caused by Foot Fungal Infection and Its Secreted Proteins, Case Report

Background The cause of many rheumatic diseases is still unknown. Some Infections might play a role, but the causative evidence is far from definitive. In this arthritic case, an association between a chronic foot fungal infection with Aspergillus sydowii (Aspsy) and arthritis was initially suggested when the treatment of foot hyperkeratosis-like lesions (Xiangya lesions) provoked multiple joints arthritis symptoms. In order to find the association of fungal infection and arthritis, data from scrupulous observations of plantar lesions, arthritic symptoms, and weather features in events of the fungal infection relapses, foot lesion manipulation, or subcutaneous injection of fungal secreted proteins were gathered and analyzed in three years. Case presentation Of the patient, relapses of the fungal infections on Xiangya lesions often occurred after rainy and humid days in winter and spring. Significant relapses of the infection aggravated the symptoms of arthritis within a few days, and the symptoms gradually improved in 2-3 weeks after the remission of fungal infection by topical antifungal treatment. Also, repeated trimming/debriding Xiangya lesion or subcutaneous injection of fungal secreted proteins also induced the arthritis symptoms similar to those of foot fungal infections. Arthritis Dermatitis, bradycardia, hypertension, and elevated blood monocytes were concurrent abnormalities. Topical methotrexate on the fresh trimmed plantar lesions was able to prevent and relieve arthritis. Conclusions Active fungal infections on plantar Xiangya lesions were associated with cold and humid weather in winter-spring or partial lesion debridement. The active fungal infections induced and exacerbated arthritis, dermatitis, and cardiovascular abnormalities. Fungal secreted proteins may mediate the fungal pathogenicity. Effective treatments of the fungal infection improved arthritis and dermatitis. These pathological characteristics have not been described before and could be a new disease, or one of the unknown pathogenic mechanisms for some known rheumatic diseases, such as rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis. The results of this research may provide an insight into a novel pathogenic mechanism for some chronic arthritis and may shed light on further clinical studies on the pathogenesis and environmental factors of some rheumatic diseases. Keywords: Arthritis of fungal protein, Aspergillus skin infection, rheumatic diseases pathogenesis, methotrexate, case report

Chondroitinase ABC reduces dopaminergic nigral cell death and striatal terminal loss in a 6-hydroxydopamine partial lesion mouse model of Parkinson’s disease

Background Parkinson’s disease (PD) is characterised by dopaminergic cell loss within the substantia nigra pars compacta (SNc) that leads to reduced striatal dopamine content and resulting motor deficits. Identifying new strategies to protect these cells from degeneration and retain striatal dopaminergic innervation is therefore of great importance. Chondroitin sulphate proteoglycans (CSPGs) are recognised contributors to the inhibitory extracellular milieu known to hinder tissue recovery following CNS damage. Digestion of these molecules by the bacterial lyase chondroitinase ABC (ChABC) has been shown to promote functional recovery in animal models of neurological injury. Although ChABC has been shown to promote sprouting of dopaminergic axons following transection of the nigrostriatal pathway, its ability to protect against nigrostriatal degeneration in a toxin-based module with better construct validity for PD has yet to be explored. Here we examined the neuroprotective efficacy of ChABC treatment in the full and partial 6-hydroxydopamine (6-OHDA) lesion mouse models of PD. Results In mice bearing a full 6-OHDA lesion, ChABC treatment failed to protect against the loss of either nigral cells or striatal terminals. In contrast, in mice bearing a partial 6-OHDA lesion, ChABC treatment significantly protected cells of the rostral SNc, which remained at more than double the numbers seen in vehicle-treated animals. In the partial lesion model, ChABC treatment also significantly preserved dopaminergic fibres of the rostral dorsal striatum which increased from 15.3 ± 3.5% of the intact hemisphere in saline-treated animals to 36.3 ± 6.5% in the ChABC-treated group. These protective effects of ChABC treatment were not accompanied by improvements in either the cylinder or amphetamine-induced rotations tests of motor function. Conclusions ChABC treatment provided significant protection against a partial 6-OHDA lesion of the nigrostriatal tract although the degree of protection was not sufficient to improve motor outcomes. These results support further investigations into the benefits of ChABC treatment for providing neuroprotection in PD.

Chondroitinase ABC reduces dopaminergic nigral cell death and striatal terminal loss in a 6-hydroxydopamine partial lesion mouse model of Parkinson’s disease

BackgroundParkinson's disease (PD) is characterised by dopaminergic cell loss within the substantia nigra pars compacta (SNc) that leads to reduced striatal dopamine content and resulting motor deficits. Identifying new strategies to protect these cells from degeneration and retain striatal dopaminergic innervation is therefore of great importance. Chondroitin sulphate proteoglycans (CSPGs) are recognised contributors to the inhibitory extracellular milieu known to hinder tissue recovery following CNS damage. Digestion of these molecules by the bacterial lyase chondroitinase ABC (ChABC) has been shown to promote functional recovery in animal models of neurological injury. Although ChABC has been shown to promote sprouting of dopaminergic axons following transection of the nigrostriatal pathway, its ability to protect against nigrostriatal degeneration in a toxin-based module with better construct validity for PD has yet to be explored. Here we examined the neuroprotective efficacy of ChABC treatment in the full and partial 6-hydroxydopamine (6-OHDA) lesion mouse models of PD. ResultsIn mice bearing a full 6-OHDA lesion, ChABC treatment failed to protect against the loss of either nigral cells or striatal terminals. In contrast, in mice bearing a partial 6-OHDA lesion, ChABC treatment significantly protected cells of the rostral SNc, which remained at more than double the numbers seen in vehicle-treated animals. In the partial lesion model, ChABC treatment also significantly preserved dopaminergic fibres of the rostral dorsal striatum which increased from 15.3 ± 3.5% of the intact hemisphere in saline-treated animals to 36.3 ± 6.5% in the ChABC-treated group. These protective effects of ChABC treatment were not accompanied by improvements in either the cylinder or amphetamine-induced rotations tests of motor function. ConclusionsChABC treatment provided significant protection against a partial 6-OHDA lesion of the nigrostriatal tract although the degree of protection was not sufficient to improve motor outcomes. These results support further investigations into the benefits of ChABC treatment for providing neuroprotection in PD.

Chondroitinase ABC reduces dopaminergic nigral cell death and striatal terminal loss in a 6-hydroxydopamine partial lesion mouse model of Parkinson’s disease

Background Parkinson's disease (PD) is characterised by dopaminergic cell loss within the substantia nigra pars compacta (SNc) that leads to reduced striatal dopamine content and resulting motor deficits. Identifying new strategies to protect these cells from degeneration and retain striatal dopaminergic innervation is therefore of great importance. Chondroitin sulphate proteoglycans (CSPGs) are recognised contributors to the inhibitory extracellular milieu known to hinder tissue recovery following CNS damage. Digestion of these molecules by the bacterial lyase chondroitinase ABC (ChABC) has been shown to promote functional recovery in animal models of neurological injury. Although ChABC has been shown to promote sprouting of dopaminergic axons following transection of the nigrostriatal pathway, its ability to protect against nigrostriatal degeneration in a more clinically-relevant toxin model of PD has yet to be explored. Here we examined the neuroprotective efficacy of ChABC treatment in the full and partial 6-hydroxydopamine (6-OHDA) lesion mouse models of PD. Results In mice bearing a full 6-OHDA lesion, ChABC treatment failed to protect against the loss of either nigral cells or striatal terminals. In contrast, in mice bearing a partial 6-OHDA lesion, ChABC treatment significantly protected cells of the rostral SNc, which remained at more than double the numbers seen in vehicle-treated animals. In the partial lesion model, ChABC treatment also significantly preserved dopaminergic fibres of the rostral dorsal striatum which increased from 15.3 ± 3.5% of the intact hemisphere in saline-treated animals to 36.3 ± 6.5% in the ChABC-treated group. These protective effects of ChABC treatment were not accompanied by improvements in either the cylinder or amphetamine-induced rotations tests of motor function. Conclusions ChABC treatment provided significant protection against a partial 6-OHDA lesion of the nigrostriatal tract although the degree of protection was not sufficient to improve motor outcomes. These results support further investigations into the benefits of ChABC treatment for providing neuroprotection in PD.

Chondroitinase ABC reduces dopaminergic nigral cell death and striatal terminal loss in a 6-hydroxydopamine partial lesion mouse model of Parkinson’s disease

Background Parkinson's disease (PD) is characterised by dopaminergic cell loss within the substantia nigra pars compacta (SNc) that leads to reduced striatal dopamine content and resulting motor deficits. Identifying new strategies to protect these cells from degeneration and retain striatal dopaminergic innervation is therefore of great importance. Chondroitin sulphate proteoglycans (CSPGs) are recognised contributors to the inhibitory extracellular milieu known to hinder tissue recovery following CNS damage. Digestion of these molecules by the bacterial lyase chondroitinase ABC (ChABC) has been shown to promote functional recovery in animal models of neurological injury. Although ChABC has been shown to promote sprouting of dopaminergic axons following transection of the nigrostriatal pathway, its ability to protect against nigrostriatal degeneration in a more clinically-relevant toxin model of PD has yet to be explored. Here we examined the neuroprotective efficacy of ChABC treatment in the full and partial 6-hydroxydopamine (6-OHDA) lesion mouse models of PD. Results In mice bearing a full 6-OHDA lesion, ChABC treatment failed to protect against the loss of either nigral cells or striatal terminals. In contrast, in mice bearing a partial 6-OHDA lesion, ChABC treatment significantly protected cells of the rostral SNc, which remained at more than double the numbers seen in vehicle-treated animals. In the partial lesion model, ChABC treatment also significantly preserved dopaminergic fibres of the rostral dorsal striatum which increased from 15.3 ± 3.5% of the intact hemisphere in saline-treated animals to 36.3 ± 6.5% in the ChABC-treated group. These protective effects of ChABC treatment were not accompanied by improvements in either the cylinder or amphetamine-induced rotations tests of motor function. Conclusions ChABC treatment provided significant protection against a partial 6-OHDA lesion of the nigrostriatal tract although the degree of protection was not sufficient to improve motor outcomes. These results support further investigations into the benefits of ChABC treatment for providing neuroprotection in PD.

Coexistence of Cervical Leiomyosarcoma and Gastric-Type Adenocarcinoma In Situ with Extensive Extension to the Endometrium and Fallopian Tube

Cervical leiomyosarcoma is known to be rare from the previous reviews of a large number of malignant cervical tumors. The patient was a 66-year-old woman with irregular vaginal bleeding. She underwent modified radical hysterectomy and bilateral salpingooophorectomy. Histopathologically, we diagnosed the coexistence of uterine cervical leiomyosarcoma and cervical gastric-type adenocarcinoma in situ with endometrial lesions that had continuous and skip patterns and fallopian tubal lesions with a partial lesion. To the best of our knowledge, cases of synchronous leiomyosarcoma and cancers have not often been reported; only two cases of synchronous cervical leiomyosarcoma and cervical squamous cell carcinoma have been published. This case is the first presentation of coincidental primary cervical leiomyosarcoma and cervical gastric-type adenocarcinoma in situ. Additionally, we considered cervical gastric-type adenocarcinoma in situ with continuous lesions on the endometrium and skip lesions on the left fallopian tube.