Journal of Neuroinflammation 

About: Journal of Neuroinflammation is an academic journal published by BioMed Central. The journal publishes majorly in the area(s): Neuroinflammation & Microglia. It has an ISSN identifier of 1742-2094. It is also open access. Over the lifetime, 3889 publications have been published receiving 182916 citations. The journal is also known as: JNI.

Neuroinflammation and M2 microglia: the good, the bad, and the inflamed.

Abstract: The concept of multiple macrophage activation states is not new. However, extending this idea to resident tissue macrophages, like microglia, has gained increased interest in recent years. Unfortunately, the research on peripheral macrophage polarization does not necessarily translate accurately to their central nervous system (CNS) counterparts. Even though pro- and anti-inflammatory cytokines can polarize microglia to distinct activation states, the specific functions of these states is still an area of intense debate. This review examines the multiple possible activation states microglia can be polarized to. This is followed by a detailed description of microglial polarization and the functional relevance of this process in both acute and chronic CNS disease models described in the literature. Particular attention is given to utilizing M2 microglial polarization as a potential therapeutic option in treating diseases.

Microglia and neuroinflammation: a pathological perspective

Abstract: Microglia make up the innate immune system of the central nervous system and are key cellular mediators of neuroinflammatory processes. Their role in central nervous system diseases, including infections, is discussed in terms of a participation in both acute and chronic neuroinflammatory responses. Specific reference is made also to their involvement in Alzheimer's disease where microglial cell activation is thought to be critically important in the neurodegenerative process.

TNF signaling inhibition in the CNS: implications for normal brain function and neurodegenerative disease

Abstract: The role of tumor necrosis factor (TNF) as an immune mediator has long been appreciated but its function in the brain is still unclear. TNF receptor 1 (TNFR1) is expressed in most cell types, and can be activated by binding of either soluble TNF (solTNF) or transmembrane TNF (tmTNF), with a preference for solTNF; whereas TNFR2 is expressed primarily by microglia and endothelial cells and is preferentially activated by tmTNF. Elevation of solTNF is a hallmark of acute and chronic neuroinflammation as well as a number of neurodegenerative conditions including ischemic stroke, Alzheimer's (AD), Parkinson's (PD), amyotrophic lateral sclerosis (ALS), and multiple sclerosis (MS). The presence of this potent inflammatory factor at sites of injury implicates it as a mediator of neuronal damage and disease pathogenesis, making TNF an attractive target for therapeutic development to treat acute and chronic neurodegenerative conditions. However, new and old observations from animal models and clinical trials reviewed here suggest solTNF and tmTNF exert different functions under normal and pathological conditions in the CNS. A potential role for TNF in synaptic scaling and hippocampal neurogenesis demonstrated by recent studies suggest additional in-depth mechanistic studies are warranted to delineate the distinct functions of the two TNF ligands in different parts of the brain prior to large-scale development of anti-TNF therapies in the CNS. If inactivation of TNF-dependent inflammation in the brain is warranted by additional pre-clinical studies, selective targeting of TNFR1-mediated signaling while sparing TNFR2 activation may lessen adverse effects of anti-TNF therapies in the CNS.

Wallerian degeneration: gaining perspective on inflammatory events after peripheral nerve injury

Abstract: In this review, we first provide a brief historical perspective, discussing how peripheral nerve injury (PNI) may have caused World War I. We then consider the initiation, progression, and resolution of the cellular inflammatory response after PNI, before comparing the PNI inflammatory response with that induced by spinal cord injury (SCI). In contrast with central nervous system (CNS) axons, those in the periphery have the remarkable ability to regenerate after injury. Nevertheless, peripheral nervous system (PNS) axon regrowth is hampered by nerve gaps created by injury. In addition, the growth-supportive milieu of PNS axons is not sustained over time, precluding long-distance regeneration. Therefore, studying PNI could be instructive for both improving PNS regeneration and recovery after CNS injury. In addition to requiring a robust regenerative response from the injured neuron itself, successful axon regeneration is dependent on the coordinated efforts of non-neuronal cells which release extracellular matrix molecules, cytokines, and growth factors that support axon regrowth. The inflammatory response is initiated by axonal disintegration in the distal nerve stump: this causes blood-nerve barrier permeabilization and activates nearby Schwann cells and resident macrophages via receptors sensitive to tissue damage. Denervated Schwann cells respond to injury by shedding myelin, proliferating, phagocytosing debris, and releasing cytokines that recruit blood-borne monocytes/macrophages. Macrophages take over the bulk of phagocytosis within days of PNI, before exiting the nerve by the circulation once remyelination has occurred. The efficacy of the PNS inflammatory response (although transient) stands in stark contrast with that of the CNS, where the response of nearby cells is associated with inhibitory scar formation, quiescence, and degeneration/apoptosis. Rather than efficiently removing debris before resolving the inflammatory response as in other tissues, macrophages infiltrating the CNS exacerbate cell death and damage by releasing toxic pro-inflammatory mediators over an extended period of time. Future research will help determine how to manipulate PNS and CNS inflammatory responses in order to improve tissue repair and functional recovery.

MOG-IgG in NMO and related disorders: a multicenter study of 50 patients. Part 2: Epidemiology, clinical presentation, radiological and laboratory features, treatment responses, and long-term outcome

Abstract: A subset of patients with neuromyelitis optica spectrum disorders (NMOSD) has been shown to be seropositive for myelin oligodendrocyte glycoprotein antibodies (MOG-IgG) To describe the epidemiological, clinical, radiological, cerebrospinal fluid (CSF), and electrophysiological features of a large cohort of MOG-IgG-positive patients with optic neuritis (ON) and/or myelitis (n = 50) as well as attack and long-term treatment outcomes Retrospective multicenter study The sex ratio was 1:28 (m:f) Median age at onset was 31 years (range 6-70) The disease followed a multiphasic course in 80% (median time-to-first-relapse 5 months; annualized relapse rate 092) and resulted in significant disability in 40% (mean follow-up 75 ± 465 months), with severe visual impairment or functional blindness (36%) and markedly impaired ambulation due to paresis or ataxia (25%) as the most common long-term sequelae Functional blindness in one or both eyes was noted during at least one ON attack in around 70% Perioptic enhancement was present in several patients Besides acute tetra-/paraparesis, dysesthesia and pain were common in acute myelitis (70%) Longitudinally extensive spinal cord lesions were frequent, but short lesions occurred at least once in 44% Fourty-one percent had a history of simultaneous ON and myelitis Clinical or radiological involvement of the brain, brainstem, or cerebellum was present in 50%; extra-opticospinal symptoms included intractable nausea and vomiting and respiratory insufficiency (fatal in one) CSF pleocytosis (partly neutrophilic) was present in 70%, oligoclonal bands in only 13%, and blood-CSF-barrier dysfunction in 32% Intravenous methylprednisolone (IVMP) and long-term immunosuppression were often effective; however, treatment failure leading to rapid accumulation of disability was noted in many patients as well as flare-ups after steroid withdrawal Full recovery was achieved by plasma exchange in some cases, including after IVMP failure Breakthrough attacks under azathioprine were linked to the drug-specific latency period and a lack of cotreatment with oral steroids Methotrexate was effective in 5/6 patients Interferon-beta was associated with ongoing or increasing disease activity Rituximab and ofatumumab were effective in some patients However, treatment with rituximab was followed by early relapses in several cases; end-of-dose relapses occurred 9-12 months after the first infusion Coexisting autoimmunity was rare (9%) Wingerchuk’s 2006 and 2015 criteria for NMO(SD) and Barkhof and McDonald criteria for multiple sclerosis (MS) were met by 28%, 32%, 15%, 33%, respectively; MS had been suspected in 36% Disease onset or relapses were preceded by infection, vaccination, or pregnancy/delivery in several cases Our findings from a predominantly Caucasian cohort strongly argue against the concept of MOG-IgG denoting a mild and usually monophasic variant of NMOSD The predominantly relapsing and often severe disease course and the short median time to second attack support the use of prophylactic long-term treatments in patients with MOG-IgG-positive ON and/or myelitis