The autonomic nerves around the vein of Marshall: a postmortem study with clinical implications.

This study aims to analyze the vein of Marshall (VOM) in human autopsy hearts and its correlation with clinical data to elucidate the morphological substrates of atrial fibrillation (AF) and other cardiac diseases. Twenty-three adult autopsy hearts were studied, assessing autonomic nerves by immunohistochemistry with tyrosine hydroxylase (sympathetic nerves), choline acetyltransferase (parasympathetic nerves), growth-associated protein 43 (neural growth), and S100 (general neural marker) antibodies. Interstitial fibrosis was assessed by Masson trichrome staining. Measurements were conducted via morphometric software. The results were correlated with clinical data. Sympathetic innervation was abundant in all VOM-adjacent regions. Subjects with a history of AF, cardiovascular cause of death, and histologically verified myocardial infarction had increased sympathetic innervation and neural growth around the VOM at the mitral isthmus. Interstitial fibrosis increased with age and heart weight was associated with AF and cardiovascular cause of death. This study increases our understanding of the cardiac autonomic innervation in the VOM area in various diseases, offering implications for the development of new therapeutic approaches targeting the autonomic nervous system.

Quantification of the intrinsic neural plexus of the heart - The missing link in histological tissue analysis.

BACKGROUND AND OBJECTIVE: The heart is under strict regulation of the autonomic nervous system, during which, in a healthy state, the effects of sympathetic and parasympathetic branches are balanced. In recent years, there has been increasing interest in pathological remodeling and outgrowth of cardiac autonomic nerves in relation to arrhythmogenesis. However, the small size of the cardiac nerves in relatively large tissues renders research using histological quantification of these nerves extremely challenging and usually relies on quantification of the nerve density in selected regions of interest only. Our aim was to develop a method to be able to quantify the histological nerve density in transmural tissue sections. METHODS: Here we describe a novel workflow that enables visualization and quantification of variable innervation types and their heterogeneity within transmural myocardial tissue sections. A custom semiautomatic workflow for the quantification of cardiac nerves involving Python, MATLAB and ImageJ is provided and described in this protocol in a stepwise and detailed manner. REPRESENTATIVE RESULTS: The results of two example tissue sections are represented in this paper. An example tissue section taken from the infarction core with a high heterogeneity value of 0.20, 63.3% normal innervation, 12.2% hyperinnervation, 3.6% hypoinnervation and 21.0% denervation. The second example tissue section taken from an area of the left ventricle remote from the infarction showed a low heterogeneity value of 0.02, 95.3% normal innervation, 3.8% hyperinnervation, 0.5% hypoinnervation and 0.5% denervation. CONCLUSIONS: This approach has the potential to be broadly applied to any research involving high-resolution imaging of nerves in large tissues.

Involvement of Abnormal p-α-syn Accumulation and TLR2-Mediated Inflammation of Schwann Cells in Enteric Autonomic Nerve Dysfunction of Parkinson's Disease: an Animal Model Study.

The study was designed to investigate the pathogenesis of gastrointestinal (GI) impairment in Parkinson's disease (PD). We utilized 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 20 mg/kg) and probenecid (250 mg/kg) to prepare a PD mice model. MPTP modeling was first confirmed. GI motility was measured using stool collection test and enteric plexus loss was also detected. Intestinal phosphorylated α-synuclein (p-α-syn), inflammation, and S100 were assessed using western blotting. Association between Toll-like receptor 2(TLR2) and GI function was validated by Pearson's correlations. Immunofluorescence was applied to show co-localizations of intestinal p-α-syn, inflammation, and Schwann cells (SCs). CU-CPT22 (3 mg/kg, a TLR1/TLR2 inhibitor) was adopted then. Success in modeling, damaged GI neuron and function, and activated intestinal p-α-syn, inflammation, and SCs responses were observed in MPTP group, with TLR2 related to GI damage. Increased p-α-syn and inflammatory factors were shown in SCs of myenteron for MPTP mice. Recovered fecal water content and depression of inflammation, p-α-syn deposition, and SCs activity were noticed after TLR2 suppression. The study investigates a novel mechanism of PD GI autonomic dysfunction, demonstrating that p-α-syn accumulation and TLR2 signaling of SCs were involved in disrupted gut homeostasis and treatments targeting TLR2-mediated pathway might be a possible therapy for PD.

Autonomic nerves in myocardial sleeves around caval veins: Potential role in cardiovascular mortality?

BACKGROUND: Quantitative changes in the cardiac autonomic nervous system may play an important role in the pathogenesis of various cardiovascular diseases. In the present morphological analysis, we aimed to study autonomic nerve density in myocardial sleeves and surrounding fibro-fatty tissue around caval veins. We correlated the nerve distribution with cardiovascular mortality and a history of atrial fibrillation. MATERIALS AND METHODS: A total of 24 autopsied adult hearts were excised together with the superior and inferior vena cava and grouped according to the immediate and underlying causes of death (cardiovascular vs. non-cardiovascular), and documented heart rhythm history (atrial fibrillation vs. sinus rhythm). The density of autonomic nerves was quantified by measuring the area of immunohistochemical staining for sympathetic (tyrosine hydroxylase, TH) and parasympathetic (choline acetyltransferase, CHAT) nerves and ganglia. Growth-associated protein 43 (GAP43) was used as a neural growth marker. RESULTS: The mean density of TH-positive nerves in the superior vena cava myocardial sleeves was significantly decreased between groups with documented underlying cardiovascular vs. non-cardiovascular cause of death (mean density ± standard deviation (SD): 704.81±1016.41 µm2/mm2 vs. 2391.01±1841.37 µm2/mm2; P = .008). Similarly, the nerve density of GAP43-positive nerves in the superior vena cava myocardial sleeves was significantly lower in subjects with documented underlying cardiovascular cause of death (mean density ± SD: 884.74±1240.16 µm2/mm2 vs. 2132.89±1845.89 µm2/mm2; P = .040). The mean age was significantly higher in subjects with documented underlying cardiovascular vs. non-cardiovascular cause of death (mean age ± SD: 69.2±11.9 years, vs. 57.5±11.2 years, P = .016). No differences were found in nerve densities of TH-positive (953.01±1042.93 µm2/mm2 vs. 919.26±1677.58 µm2/mm2), CHAT-positive (180.8±532.9 µm2/mm2 vs. 374.22±894.76 µm2/mm2), and GAP43-positive nerves (593.58±507.97 µm2/mm2 vs. 1337.34±1747.69 µm2/mm2) in myocardial sleeves around the inferior vena cava between groups with documented immediate cardiovascular vs. non-cardiovascular cause of death. Similarly, no differences were found between groups with documented underlying cardiovascular vs. non-cardiovascular cause of death (TH: 717.23±887.31 µm2/mm2 vs. 1365.51±2149.10 µm2/mm2; CHAT: 256.18±666.86 µm2/mm2 vs. 368.53±959.47 µm2/mm2; GAP43: 661.21±839.51 µm2/mm2 vs. 1759.90±2008.80 µm2/mm2). Moreover, there was no association found in nerve densities between subjects with documented atrial fibrillation vs. sinus rhythm (TH: 235.07±425.69 µm2/mm2 vs. 1166.08±1563.84 µm2/mm2; CHAT: 648.59±1017.33 µm2/mm2 vs. 175.31±641.65 µm2/mm2; GAP43: 990.17±1315.18 µm2/mm2 vs. 1039.86±1467.23 µm2/mm2). CONCLUSIONS: Decrease of superior vena cava myocardial sleeve sympathetic nerves may be associated with cardiovascular mortality and/or aging. No difference in autonomic innervation was found between subjects with documented atrial fibrillation vs. sinus rhythm.

Cutaneous sensory and autonomic denervation in progressive supranuclear palsy.

AIM: Progressive Supranuclear Palsy (PSP) is a progressive neurodegenerative tauopathy characterised by motor, behavioural and cognitive dysfunction. While in the last decade, sensory and autonomic disturbances as well as peripheral nerve involvement are well-recognised in Parkinson's Disease (PD), little is known in this regard for PSP. Herein, we aim to assess peripheral sensory and autonomic nerve involvement in PSP and to characterise possible differences in morpho-functional pattern compared to PD patients. METHODS: We studied 27 PSP and 33 PD patients without electrophysiological signs of neuropathy, and 33 healthy controls (HC). In addition to motor impairment, evaluated by means of UPDRS-III and the PSP rating scale, all patients underwent clinical, functional and morphological assessment of sensory-autonomic nerves through dedicated questionnaires, sympathetic skin response, dynamic sweat test and skin biopsies. The analysis of cutaneous sensory and autonomic innervation was performed using indirect immunofluorescence and confocal microscopy. RESULTS: PSP patients displayed a length-dependent loss of sensory and autonomic nerve fibres associated with functional impairment compared to HC and, overall, a more severe picture than in PD patients. The disease severity correlated with the loss of intraepidermal nerve fibre density in the leg of PSP patients (p < 0.05). CONCLUSION: We demonstrated a length-dependent small fibre pathology in PSP, more severe compared to PD, and paralleling disease severity. Our findings suggest the morphological and functional study of cutaneous nerves as possible biomarkers to monitor disease progression and response to new treatments.

Relationship between electrocardiographic changes and EPO level in stable CAD patients with autonomic nerve functional damage.

OBJECTIVE: To investigate the relationship between electrocardiographic changes and erythropoietin (EPO) level in stable coronary artery disease (CAD) patients with autonomic nerve functional damage. PATIENTS AND METHODS: Clinical data of 96 stable CAD patients who were treated in our hospital from January 2017 to December 2019 were retrospectively analyzed. All patients were grouped according to whether autonomic nerve function damage was combined; the baseline characteristic data and the morphological characteristics of ECG scattergram were compared between 2 groups, and the relationship between ECG scattergram and EPO level & autonomic nerve function was analyzed. RESULTS: The levels of EPO and red cell volume distributing width (RDW) in stable CAD patients with autonomic nerve dysfunction were significantly higher than that of CAD patients without autonomic nerve dysfunction (p<0.05). The length of scattergram in stable CAD patients with autonomic nerve dysfunction was significantly shorter than that of those without autonomic nerve dysfunction (p<0.05). The cometary sign proportion of ECG scattergram in stable CAD patients with autonomic nerve dysfunction was significantly lower than that of stable CAD patients without autonomic nerve dysfunction (p<0.05). There was negative correlation between EPO levels and scattergram length in stable CAD patients with and without autonomic nerve dysfunction (r=0.44, p=0.02). There was no correlation between EPO levels and scatter width in stable CAD patients with and without autonomic nerve dysfunction (r=0.10, p=0.58). The results of binary logistic regression analysis showed that EPO level was the independent risk factor for the occurrence of autonomic dysfunction in patients with stable CAD (p<0.05). The length of scattergram was the independent protective factor of autonomic nerve function impairment in patients with stable CAD (p<0.05). The AUC of EPO level and scattergram was 0.74 and 0.72 respectively, both of which have similar prediction value. CONCLUSIONS: The level of EPO in stable CAD patients with autonomic nerve dysfunction was related to the change of ECG; and the EPO level and scattergram length can be used to predict the occurrence risk of autonomic nerve dysfunction.

Phosphorylated Alpha-Synuclein Within Cutaneous Autonomic Nerves of Patients With Parkinson's Disease: The Implications of Sample Thickness on Results.

The detection of cutaneous phosphorylated alpha-synuclein (P-syn) in patients with Parkinson's disease (PD) has ranged from 30% to 100% across different studies. We hypothesize that part of the variability in P-syn detection is due to methodological differences using sections of different tissue thickness. Three skin biopsies were obtained from 29 individuals with PD and 21 controls. Tissues were cut into 10-, 20-, and 50-µm-thick sections and double-stained with protein gene product (PGP) 9.5 and P-syn. We quantified the deposition of P-syn with and without PGP 9.5 in sweat glands, pilomotor muscle, and blood vessels using confocal digital images of autonomic structures. Overall, the P-syn-positive rates with PGP 9.5 colocalization in subjects with PD were 100% using 50 µm sections, 90% using 20 µm sections, and 73% using 10 µm sections with 100% specificity. (No P-syn was detected within control subjects.) Without PGP 9.5, colocalization of the P-syn-positive rates was 100% for all samples, but specificity dropped below 70%. In this study, double-immunostained 50 µm skin biopsy tissue sections are superior to 20 and 10 µm tissue sections at detecting P-syn in subjects with PD. The increased sensitivity is likely secondary to a combination of greater volume of tissue analyzed and improved visualization of nerve fiber architecture.

Unusual Incidence and Location of Renaut Bodies in Beagle Dogs in a Nonclinical Study.

We identified the presence of Renaut bodies in an unusual location in Beagle dogs on a 3-month nonclinical toxicity study. These peculiar structures are commonly reported as a background finding in the sciatic nerve of dogs. In our study, however, they were also observed in autonomic nerves surrounding the adrenal gland, a location in which they have not been reported before. The incidence in both locations were 8 of 32 Beagle dogs in the sciatic nerve and 6 of 40 Beagle dogs around the adrenal gland in the dosing and/or recovery phases of the study.

Síndrome de Horner: revision de la literatura / Horner´s Syndrome: literature review

Resumen El Síndrome de Horner (SH) es una condición provocada por un grupo heterogéneo de patologías. Estas tienen en común el daño de la vía simpática. La localización más común de la lesión es a nivel preganglionar, por trauma o cirugías en región cervical, torácica o ápex pulmonar. El diagnóstico es primordialmente clínico mediante la identificación de la triada de miosis, ptosis y anhidrosis. Se confirma con las pruebas para cocaína e hidroximetanfetamina. El tratamiento se lleva a cabo primero con agentes farmacológicos. Los que tienen disminución del campo visual por la ptosis o por razones cosméticas se llevan a tratamiento quirúrgico. En ese caso los abordajes operatorios recomendados para ptosis leve son el procedimiento de Fasanella-Servat, el avance de aponeurosis del elevador y en casos severos el cabestrillo frontal. El objetivo es hacer una revisión de los algoritmos diagnósticos y terapéuticos del SH para lograr un abordaje sistemático debido a las múltiples etiologías que posee.

Abstract Horner Syndrome is a condition caused by a heterogeneous group of pathologies. These have in common the damage of the sympathetic pathway. The most common location of the lesion is at the preganglional level, due to trauma or surgeries in the cervical, thoracic or pulmonary apex region. The diagnosis is primarily clinical by identifying the triad of myosis, ptosis and anhidrosis. It is confirmed with the cocaine and hydroxymethamphetamine tests. Treatment is first carried out with pharmacological agents. Those with diminished visual field due to ptosis or cosmetic reasons are undergoing surgical treatment. In this case, the recommended operative approaches for mild ptosis are the Fasanella-Servat procedure, the elevator aponeurosis advance and, in severe cases, the frontalis sling. The objective is to review the diagnostic and therapeutic algorithms of SH in order to achieve a systematic approach due to the multiple aetiologies it possesses.

Hyperactivation of sympathetic nerves drives depletion of melanocyte stem cells.

Empirical and anecdotal evidence has associated stress with accelerated hair greying (formation of unpigmented hairs)1,2, but so far there has been little scientific validation of this link. Here we report that, in mice, acute stress leads to hair greying through the fast depletion of melanocyte stem cells. Using a combination of adrenalectomy, denervation, chemogenetics3,4, cell ablation and knockout of the adrenergic receptor specifically in melanocyte stem cells, we find that the stress-induced loss of melanocyte stem cells is independent of immune attack or adrenal stress hormones. Instead, hair greying results from activation of the sympathetic nerves that innervate the melanocyte stem-cell niche. Under conditions of stress, the activation of these sympathetic nerves leads to burst release of the neurotransmitter noradrenaline (also known as norepinephrine). This causes quiescent melanocyte stem cells to proliferate rapidly, and is followed by their differentiation, migration and permanent depletion from the niche. Transient suppression of the proliferation of melanocyte stem cells prevents stress-induced hair greying. Our study demonstrates that neuronal activity that is induced by acute stress can drive a rapid and permanent loss of somatic stem cells, and illustrates an example in which the maintenance of somatic stem cells is directly influenced by the overall physiological state of the organism.

Nerves in cancer.

The contribution of nerves to the pathogenesis of malignancies has emerged as an important component of the tumour microenvironment. Recent studies have shown that peripheral nerves (sympathetic, parasympathetic and sensory) interact with tumour and stromal cells to promote the initiation and progression of a variety of solid and haematological malignancies. Furthermore, new evidence suggests that cancers may reactivate nerve-dependent developmental and regenerative processes to promote their growth and survival. Here we review emerging concepts and discuss the therapeutic implications of manipulating nerves and neural signalling for the prevention and treatment of cancer.

Targeting Ligands Deliver Model Drug Cargo into the Central Nervous System along Autonomic Neurons.

While biologic drugs such as proteins, peptides, or nucleic acids have shown promise in the treatment of neurodegenerative diseases, the blood-brain barrier (BBB) severely limits drug delivery to the central nervous system (CNS) after systemic administration. Consequently, drug delivery challenges preclude biological drug candidates from the clinical armamentarium. In order to target drug delivery and uptake into to the CNS, we used an in vivo phage display screen to identify peptides able to target drug-uptake by the vast array of neurons of the autonomic nervous system (ANS). Using next-generation sequencing, we identified 21 candidate targeted ANS-to-CNS uptake ligands (TACL) that enriched bacteriophage accumulation and delivered protein-cargo into the CNS after intraperitoneal (IP) administration. The series of TACL peptides were synthesized and tested for their ability to deliver a model enzyme (NeutrAvidin-horseradish peroxidase fusion) to the brain and spinal cord. Three TACL-peptides facilitated significant active enzyme delivery into the CNS, with limited accumulation in off-target organs. Peptide structure and serum stability is increased when internal cysteine residues are cyclized by perfluoroarylation with decafluorobiphenyl, which increased delivery to the CNS further. TACL-peptide was demonstrated to localize in parasympathetic ganglia neurons in addition to neuronal structures in the hindbrain and spinal cord. By targeting uptake into ANS neurons, we demonstrate the potential for TACL-peptides to bypass the blood-brain barrier and deliver a model drug into the brain and spinal cord.

The effect of pyridostigmine on small intestinal bacterial overgrowth (SIBO) and plasma inflammatory biomarkers in HIV-associated autonomic neuropathies.

Small intestinal bacterial overgrowth (SIBO) is common among patients with HIV-associated autonomic neuropathies (HIV-AN) and may be associated with increased bacterial translocation and elevated plasma inflammatory biomarkers. Pyridostigmine is an acetylcholinesterase inhibitor which has been used to augment autonomic signaling. We sought preliminary evidence as to whether pyridostigmine could improve proximal gastrointestinal motility, reduce SIBO, reduce plasma sCD14 (a marker of macrophage activation and indirect measure of translocation), and reduce the inflammatory cytokines IL-6 and TNFα in patients with HIV-AN. Fifteen participants with well-controlled HIV, HIV-AN, and SIBO were treated with 8 weeks of pyridostigmine (30 mg PO TID). Glucose breath testing for SIBO, gastric emptying studies (GES) to assess motility, plasma sCD14, IL-6, and TNFα, and gastrointestinal autonomic symptoms were compared before and after treatment. Thirteen participants (87%) experienced an improvement in SIBO following pyridostigmine treatment; with an average improvement of 50% (p = 0.016). There was no change in gastrointestinal motility; however, only two participants met GES criteria for gastroparesis at baseline. TNFα and sCD14 levels declined by 12% (p = 0.004) and 19% (p = 0.015), respectively; there was no significant change in IL-6 or gastrointestinal symptoms. Pyridostigmine may ameliorate SIBO and reduce levels of sCD14 and TNFα in patients with HIV-AN. Larger placebo-controlled studies are needed to definitively delineate how HIV-AN affects gastrointestinal motility, SIBO, and systemic inflammation in HIV, and whether treatment improves clinical outcomes.

Prostatic nerve subtypes independently predict biochemical recurrence in prostate cancer.

OBJECTIVE: To describe nerve subtypes involved by perineural invasion (PNI) in prostate cancer and their relationship with clinicopathological parameters and recurrence risk. METHODS: 141 prostatectomy specimens from men with localized prostate cancer and known perineural invasion were analyzed. Index tumor blocks were stained for perineural invasion and sympathetic/parasympathetic markers. For 98 patients with complete staining, nerves from up to three hotspot regions of intraprostatic perineural invasion were classified according to autonomic subtype and perineural invasion status. Findings were correlated with prospectively collected clinicopathological data. Biochemical recurrence predictors were tested in univariable and multivariable models. RESULTS: Most intra-prostatic nerves contained sympathetic and parasympathetic fibres, irrespective of perineural invasion status. A fraction was purely sympathetic (5% PNI, 2% non-PNI) or double-negative (non-adrenergic, non-nitrergic; 1% PNI, 1% non-PNI). Perineural invasion nerve count was associated with higher pathological stage. Although total perineural invasion or non-perineural invasion nerve count did not predict biochemical recurrence, two subtypes were found to be independent predictors: pure sympathetic non-perineural invasion nerves (HR 6.79, p = 0.03) and non-adrenergic, non-nitrergic PNI nerves (HR 10.56, p < 0.005). CONCLUSIONS: Pure sympathetic nerve density without tumour invasion and perineural invasion specifically involving non-adrenergic, non-nitrergic fibres are independent predictors of biochemical recurrence post prostatectomy, supporting a role for the autonomic nervous system in prostate cancer progression.

Skin nerve α-synuclein deposits in Parkinson's disease and other synucleinopathies: a review.

PURPOSE: The in vivo diagnosis of synucleinopathies is an important research aim since clinical diagnostic criteria show low accuracy. The skin innervation, especially the autonomic subdivision, is a useful region to search for abnormal α-syn aggregates in synucleinopathies since the peripheral sympathetic nerves can be the earliest-affected neural region and autonomic symptoms may precede the classical symptoms of these disorders. METHODS: The major advantages of skin biopsy as an in vivo diagnostic tool for synucleinopathies are that it is an inexpensive and easy-to-perform technique requiring only limited facilities, and that it is repeatable in long-term studies as it causes only minor discomfort to the patient. RESULTS: This review analyzes current progress in this area of research that may facilitate the standardization of this method, potentially eliminating differences among laboratories in the implementation of the method. CONCLUSIONS: The most suitable and commonly used technique for identifying in vivo α-syn aggregates in skin nerves is indirect immunofluorescence, although several aspects of this approach need to be standardized, particularly when synucleinopathies without autonomic failure present a patchy distribution of abnormal α-syn aggregates in skin nerves. By contrast, synucleinopathies with autonomic failure may present widespread diffusion of abnormal aggregates in autonomic skin nerves.

Proteomic Analysis of Pelvic Autonomic Nerve in Nerve-sparing Radical Hysterectomy for Cervical Carcinoma.

BACKGROUND/AIM: This study was designed to identify candidate proteins which can be used for visualization of pelvic autonomic nerve during nerve-sparing surgery. MATERIALS AND METHODS: Both soft tissue and vesical branch of the inferior hypogastric nerve from five women were collected during surgery. These 10 tissue specimens were analysed using liquid chromatography-mass spectrometry (LC-MS) and Human Protein Atlas (HPA) for protein expression. The existence of nerve fibres was confirmed using haematoxylin and eosin (H&E) and anti-S-100 staining. RESULTS: A total of 413 proteins were detected. There were three proteins (isoform 1 of fibronectin, protein S100-A8 and A9) which implied a relation with pelvic autonomic nerve. In nerve tissue from one case, the existence of nerve fibre was not confirmed. CONCLUSION: Further large studies are expected to present more nerve-specific candidate proteins which can be used for the easy and safe identification of autonomic nerves.

Definition and diagnosis of small fiber neuropathy: consensus from the Peripheral Neuropathy Scientific Department of the Brazilian Academy of Neurology.

The aim of this study was to describe the results of a Brazilian Consensus on Small Fiber Neuropathy (SFN). Fifteen neurologists (members of the Brazilian Academy of Neurology) reviewed a preliminary draft. Eleven panelists got together in the city of Fortaleza to discuss and finish the text for the manuscript submission. Small fiber neuropathy can be defined as a subtype of neuropathy characterized by selective involvement of unmyelinated or thinly myelinated sensory fibers. Its clinical picture includes both negative and positive manifestations: sensory (pain/dysesthesias/pruritus) or combined sensory and autonomic complaints, associated with an almost entirely normal neurological examination. Standard electromyography is normal. A growing list of medical conditions is associated with SFN. The classification of SFN may also serve as a useful terminology to uncover minor discrepancies in the normal values from different neurophysiology laboratories. Several techniques may disclose sensory and/or autonomic impairment. Further studies are necessary to refine these techniques and develop specific therapies.

Cutaneous somatic and autonomic nerve TDP-43 deposition in amyotrophic lateral sclerosis.

OBJECTIVE: To evaluate the involvement of the sensory and autonomic nervous system in amyotrophic lateral sclerosis (ALS) and to determine whether TDP-43/pTDP-43 deposits in skin nerve fibers signify a valuable biomarker for ALS. METHODS: Eighteen patients with ALS and 18 age- and sex-matched control subjects underwent physical examinations, in addition to donating skin biopsies from the distal leg. The density of epidermal, Meissner's corpuscle (MC), sudomotor, and pilomotor nerve fibers were measured. Confocal microscopy was used to determine the cutaneous somatic and autonomic nerve fiber density and TDP-43/pTDP-43 deposition. RESULTS: Intraepidermal nerve fiber density (IENFD) was reduced in individuals with ALS (P < 0.001). MC density (MCD) (P = 0.001), sweat gland nerve fiber density (SGNFD) (P < 0.001), and pilomotor nerve fiber density (PNFD) (P < 0.001) were all reduced in ALS patients. The SGNFD correlated with the small-fiber neuropathy Symptoms Inventory Questionnaire (SFN-SIQ), VAS and age. The SFN-SIQ was higher in ALS with sensory symptoms than without sensory symptoms (P = 0.000). Furthermore, the SFN-SIQ was higher in ALS with autonomic symptoms than without autonomic symptoms (P = 0.002). SFN-SIQ was higher in ALS patients that were pTDP-43 positive than pTDP-43 negative (P = 0.04), respectively. CONCLUSIONS: We established in the peripheral nervous system that higher SFN-SIQ and VAS was involved in ALS, indicating the loss of SGNF. The deposition of TDP-43/pTDP-43 in ALS nerve fibers may indicate an important role in the underlying pathogenesis of ALS. This observation might be used as a potential biomarker for diagnosing ALS.

Definition and diagnosis of small fiber neuropathy: consensus from the Peripheral Neuropathy Scientific Department of the Brazilian Academy of Neurology / Definição e diagnóstico de neuropatia de fibras finas: consenso do Departamento Científico de Neuropatias Periféricas da Academia Brasileira de Neurologia

ABSTRACT The aim of this study was to describe the results of a Brazilian Consensus on Small Fiber Neuropathy (SFN). Fifteen neurologists (members of the Brazilian Academy of Neurology) reviewed a preliminary draft. Eleven panelists got together in the city of Fortaleza to discuss and finish the text for the manuscript submission. Small fiber neuropathy can be defined as a subtype of neuropathy characterized by selective involvement of unmyelinated or thinly myelinated sensory fibers. Its clinical picture includes both negative and positive manifestations: sensory (pain/dysesthesias/pruritus) or combined sensory and autonomic complaints, associated with an almost entirely normal neurological examination. Standard electromyography is normal. A growing list of medical conditions is associated with SFN. The classification of SFN may also serve as a useful terminology to uncover minor discrepancies in the normal values from different neurophysiology laboratories. Several techniques may disclose sensory and/or autonomic impairment. Further studies are necessary to refine these techniques and develop specific therapies.

RESUMO O objetivo deste estudo é descrever os resultados de um Consenso Brasileiro sobre Neuropatia de Fibras Finas (NFF). Quinze neurologistas (membros da Academia Brasileira de Neurologia) revisaram uma versão preliminar do artigo. Onze panelistas se reuniram na cidade de Fortaleza para discutir e terminar o texto para a submissão do manuscrito. NFF pode ser definida como um subtipo de neuropatia caracterizada pelo envolvimento seletivo de fibras sensitivas amielínicas ou pouco mielinizadas. Seu quadro clínico inclui manifestações negativas e positivas: sensitivas (dor/disestesias/prurido) ou queixas sensitivas e autonômicas combinadas, associadas a exame neurológico quase totalmente normal. A eletromiografia convencional é normal. Uma lista crescente de condições médicas causa NFF. NFF também pode servir como uma terminologia útil para referenciar pequenas discrepâncias nos valores normais de diferentes laboratórios de neurofisiologia. Diferentes técnicas podem evidenciar anormalidades sensitivas e/ou autonômicas. São necessários mais estudos para refiná-las e para o desenvolvimento de terapias específicas.

Long-Term Improvement of Neurological Signs and Metabolic Dysfunction in a Mouse Model of Krabbe's Disease after Global Gene Therapy.

We report a global adeno-associated virus (AAV)9-based gene therapy protocol to deliver therapeutic galactosylceramidase (GALC), a lysosomal enzyme that is deficient in Krabbe's disease. When globally administered via intrathecal, intracranial, and intravenous injections to newborn mice affected with GALC deficiency (twitcher mice), this approach largely surpassed prior published benchmarks of survival and metabolic correction, showing long-term protection of demyelination, neuroinflammation, and motor function. Bone marrow transplantation, performed in this protocol without immunosuppressive preconditioning, added minimal benefits to the AAV9 gene therapy. Contrasting with other proposed pre-clinical therapies, these results demonstrate that achieving nearly complete correction of GALC's metabolic deficiencies across the entire nervous system via gene therapy can have a significant improvement to behavioral deficits, pathophysiological changes, and survival. These results are an important consideration for determining the safest and most effective manner for adapting gene therapy to treat this leukodystrophy in the clinic.