Tumor necrosis factor (TNF) is considered a major proinflammatory cytokine, affecting various aspects of the immune reaction. All five TNF inhibitors currently available on the market (i.e., etanercept, infliximab, adalimumab, certolizumab and golimumab) are top sellers, although indicated only in autoimmune diseases, including rheumatoid arthritis, Crohn's disease and psoriasis. This article briefly discusses the background and place for TNF inhibitors in modern therapy. The main safety aspects of TNF inhibitor administration are described in particular, with special consideration of the available meta-analyses. Finally, perspectives on the next-generation TNF inhibitors and their use in the clinic are given.
Many chronic trigeminal pain conditions, such as migraine or temporo-mandibular disorders, are associated with inflammation within peripheral endings of trigeminal ganglion (TG) sensory neurons. A critical role in mechanisms of neuroinflammation is attributed to proinflammatory cytokines, such as interleukin-1β and tumor necrosis factor-α (TNFα) that also contribute to mechanisms of persistent neuropathic pain resulting from nerve injury. However, the mechanisms of cytokine-mediated synaptic plasticity and nociceptor sensitization are not completely understood. In the present study, we examined the effects of TNFα on neuronal expression of brain-derived neurotrophic factor (BDNF), whose role in synaptic plasticity and sensitization of nociceptive pathways is well documented. We show that 4-and 24-hr treatment with TNFα increases BDNF mRNA and protein, respectively, in neuron-enriched dissociated cultures of rat TG. TNFα increases the phosphorylated form of the cyclic adenosine monophosphate-responsive element binding protein (CREB), a transcription factor involved in regulation of BDNF expression in neurons, and activates transcription of BDNF exon IV (former exon III) and, to a lesser extent, exon VI (former exon IV), but not exon I. TNFα-mediated increase in BDNF expression was accompanied by increase in calcitonin gene-related peptide (CGRP), which is consistent with © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.Corresponding author: Dr. Agnieszka Balkowiec, Department of Integrative Biosciences, Oregon Health and Science University School of Dentistry, 611 S.W. Campus Drive, Portland, OR 97239; Phone: (503) 418-0190; Fax: (503) 494-8554; balkowie@ohsu.edu. All experimental protocols are available in a detailed, step-by-step format upon request from Dr. Ewa Bałkowiec-Iskra (ebalkowiec@wum.edu.pl).. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.Research Highlights:1. BDNF mRNA and protein are upregulated in trigeminal ganglion neurons by TNF-α 2. TNF-α upregulates BDNF expression in a promoter-selective manner 3. TNF-α upregulation of BDNF expression is potentiated by neuronal activity and cAMP 4. TNF-α upregulation of BDNF expression depends on sodium channels and p38-MAPK 5. These data have implications for BDNF-dependent sensory plasticity NIH Public Access Vitkovic et al., 2000;Boulanger, 2009;Carpentier and Palmer, 2009). Thus, identifying the mechanisms that underlie neuro-immune interactions could become fundamental to understanding how the nervous system functions under physiological conditions and what goes awry in the disorders whose pa...
Tumor necrosis factor inhibitors (TNFi) belong to the group of biologic drugs, holding presently top positions on lists of most profitable products for pharmaceutical companies. Although current indications for TNFi include only selected diseases with an established role of immune dysfunction in their pathogenesis, studies on new indications are being carried out all over the world. The most important aspect of TNFi therapy is a targeted therapeutic approach, allowing to avoid a wide range of side effects associated with treatment with nonspecific immunosuppressive agents. Results of the trials on TNFi in the approved indications are widely accessible and analyzed elsewhere, both in primary publications as well as in systematic reviews and meta-analyses. Here we aim to discuss their mechanisms of action, and approved, as well as off-label indications of TNFi. In addition, we present comprehensive evidence on TNFi in treatment of rheumatoid arthritis (RA); the first authorized and probably most extensively developed indication for the majority of TNFi.
Nociceptive pathways with first-order neurons located in the trigeminal ganglion (TG) provide sensory innervation to the head, and are responsible for a number of common chronic pain conditions, including migraines, temporomandibular disorders and trigeminal neuralgias. Many of those conditions are associated with inflammation. Yet, the mechanisms of chronic inflammatory pain remain poorly understood. Our previous studies show that the neurotrophin brain-derived neurotrophic factor (BDNF) is expressed by adult rat TG neurons, and released from cultured newborn rat TG neurons by electrical stimulation and calcitonin gene-related peptide (CGRP), a well-established mediator of trigeminal inflammatory pain. These data suggest that BDNF plays a role in activity-dependent plasticity at first-order trigeminal synapses, including functional changes that take place in trigeminal nociceptive pathways during chronic inflammation. The present study was designed to determine the effects of peripheral inflammation, using tooth pulp inflammation as a model, on regulation of BDNF expression in TG neurons of juvenile rats and mice. Cavities were prepared in right-side maxillary first and second molars of 4-week-old animals, and left open to oral microflora. BDNF expression in right TG was compared with contralateral TG of the same animal, and with right TG of sham-operated controls, 7 and 28 days after cavity preparation. Our ELISA data indicate that exposing the tooth pulp for 28 days, with confirmed inflammation, leads to a significant upregulation of BDNF in the TG ipsilateral to the affected teeth. Double-immunohistochemistry with antibodies against BDNF combined with one of nociceptor markers, CGRP or TRPV1, revealed that BDNF is significantly upregulated in TRPV1-immunoreactive (IR) neurons in both rats and mice, and CGRP-IR neurons in mice, but not rats. Overall, the inflammation-induced upregulation of BDNF is stronger in mice compared to rats. Thus, mouse TG provides a suitable model to study molecular mechanisms of inflammation-dependent regulation of BDNF expression in vivo.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.