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Dupilumab, a human monoclonal antibody, blocks the shared receptor unit for interleukin-4 and interleukin-13. International phase II and III studies have evaluated the efficacy and safety of dupilumab in adults with moderate-to-severe atopic dermatitis (AD), but dupilumab effects in Japanese patients have not been reported.
Previous reports show that moderate prenatal alcohol exposure (PAE) poses a risk factor for developing neuropathic pain following adult-onset peripheral nerve injury in male rats. Recently, evidence suggests that immune-related mechanisms underlying neuropathic pain in females are different compared to males despite that both sexes develop neuropathy of similar magnitude and duration following chronic constriction injury (CCI) of the sciatic nerve. Data suggest that the actions of peripheral T cells play a greater role in mediating neuropathy in females. The goal of the current study is to identify specificity of immune cell and cytokine changes between PAE and non-PAE neuropathic females by utilizing a well-characterized rodent model of sciatic nerve damage, in an effort to unmask unique signatures of immune-related factors underlying the risk of neuropathy from PAE. Cytokines typically associated with myeloid cell actions such as interleukin (IL)-1β, tumor necrosis factor (TNF), IL-6, IL-4 and IL-10 as well as the neutrophil chemoattractant CXCL1, are examined. In addition, transcription factors and cytokines associated with various differentiated T cell subtypes are examined (anti-inflammatory FOXP3, proinflammatory IL-17A, IL-21, ROR-γt, interferon (IFN)-γ and T-bet). Lymphocyte function associated antigen 1 (LFA-1) is an adhesion molecule expressed on peripheral immune cells including T cells and regulates T cell activation and extravasation into inflamed tissue regions. A potential therapeutic approach was explored with the goal of controlling proinflammatory responses in neuroanatomical regions critical for CCI-induced allodynia by blocking LFA-1 actions using BIRT377. The data show profound development of hindpaw allodynia in adult non-PAE control females following standard CCI, but not following minor CCI, while minor CCI generated allodynia in PAE females. The data also show substantial increases in T cell-associated proinflammatory cytokine mRNA and proteins, along with evidence of augmented myeloid/glial activation (mRNA) and induction of myeloid/glial-related proinflammatory cytokines, CCL2, IL-1β and TNF in discrete regions along the pain pathway (damaged sciatic nerve, dorsal root ganglia; DRG, and spinal cord). Interestingly, the characteristic anti-inflammatory IL-10 protein response to nerve damage is blunted in neuropathic PAE females. Moreover, T cell profiles are predominantly proinflammatory in neuropathic Sac and PAE females, augmented levels of Th17-specific proinflammatory cytokines IL-17A and IL-21, as well as the Th1-specific factor, T-bet, are observed. Similarly, the expression of RORγt, a critical transcription factor for Th17 cells, is detected in the spinal cord of neuropathic females. Blocking peripheral LFA-1 actions with intravenous (i.v.) BIRT377 reverses allodynia in Sac and PAE rats, dampens myeloid (IL-1β, TNF, CXCL1)- and T cell-associated proinflammatory factors (IL-17A and RORγt) and spinal glial activation. Moreover, i.v. BIRT377 treatment reverses the blunted IL-10 response to CCI observed only in neuropathic PAE rats and elevates FOXP3 in pain-reversed Sac rats. Unexpectedly, intrathecal BIRT377 treatment is unable to alter allodynia in either Sac or PAE neuropathic females. Together, these data provide evidence that: 1) fully differentiated proinflammatory Th17 cells recruited at the sciatic nerve, DRGs and lumbar spinal cord may interact with the local environment to shape the immune responses underlying neuropathy in female rats, and, 2) PAE primes peripheral and spinal immune responses in adult females. PAE is a risk factor in females for developing peripheral neuropathy after minor nerve injury.
Nerve injury-induced change in gene expression in primary sensory neurons of dorsal root ganglion (DRG) is critical for neuropathic pain genesis. N-methyladenosine (mA) modification of RNA represents an additional layer of gene regulation. Here, it is reported that peripheral nerve injury increases the expression of the mA demethylase fat-mass and obesity-associated proteins (FTO) in the injured DRG via the activation of Runx1, a transcription factor that binds to the gene promoter. Mimicking this increase erases mA in euchromatic histone lysine methyltransferase 2 () mRNA (encoding the histone methyltransferase G9a) and elevates the level of G9a in DRG and leads to neuropathic pain symptoms. Conversely, blocking this increase reverses a loss of mA sites in mRNA and destabilizes the nerve injury-induced G9a upregulation in the injured DRG and alleviates nerve injury-associated pain hypersensitivities. FTO contributes to neuropathic pain likely through stabilizing nerve injury-induced upregulation of G9a, a neuropathic pain initiator, in primary sensory neurons.
Chronic neuropathic pain was an intractable clinical problem and challenge to the quality of life of patients. It is essential to unveil the mechanisms that drive chronic pain so as to formulate new strategies for therapy of chronic pain. The medial prefrontal context (mPFC) plays a pivotal role in pathogenesis of chronic pain. However, its underlying molecular mechanisms are largely elusive. Herein, we demonstrated that mitogen-activated protein kinase-phosphatase1 (MKP1), a negative regulatory factor of mitogen activated protein kinases (MAPKs), was activated and persistently upregulated in the mPFC neurons by qPCR and western blotting assays following chronic constrictive injury (CCI) in mice. Inhibition of MKP1 in the mPFC contralateral to the injury site could reverse CCI-induced pain behavior and neuronal activity either via employment of BCI (MKP1 antagonist) or Lenti-MKP1 particles. Furthermore, we identified the substrates of MKP1 in the mPFC involved in chronic neuropathic pain. The western blot results showed that the phosphorylation of p38 and JNK1/2 was significantly decreased after CCI, while the phosphorylation of ERK1/2 was significantly increased, suggesting that p38 and JNK1/2 were the substrates of MKP1 in mouse mPFC, but not ERK1/2. Additionally, microinjection of BCI in the mPFC contralateral to the injury side could reverse downregulation of p- p38 and p- JNK1/2 in CCI mice. SB203580 (p38 inhibitor) or SP600125 (JNK1/2 inhibitor) could reverse BCI-induced analgesia. Our findings validated that MKP1 in the mPFC modulated chronic neuropathic pain via p38 and JNK1/2, suggesting a possible MKP1-mediated process would participate in neuronal transmission pathways implicated in pain modulation.
Alexithymia, or difficulty identifying and describing emotions and sensations, contributes to an increased risk of chronic pain, and low help-seeking. To investigate whether family caregivers of advanced cancer patients visiting a palliative care department had alexithymia, and whether this was related to their pain intensity, personalized pain goals, and help-seeking for chronic musculoskeletal pain. A single-center cross-sectional survey. Pain intensity was evaluated using a numerical rating scale. Pain improvement was evaluated against personal goals. Alexithymia was assessed using the Toronto Alexithymia Scale-20 (TAS-20), and anxiety and depression using the Hospital Anxiety and Depression Scale. Of 320 family caregivers visiting the palliative care department, 152 (47.5%) had chronic musculoskeletal pain; all 152 were included in the study. Alexithymia was observed in 36.2% of participants. Participants with higher scores on the TAS-20 tended to have higher pain intensity scores and personal pain goal scores. TAS-20 score had the strongest correlation with personal pain goals, with a correlation coefficient of 0.555 ( < 0.001). Pain intensity in family caregivers with alexithymia tended to be high. These participants set higher personal pain goals (lower goals for symptom improvement) than those without alexithymia. We found no difference in personal pain goal response between family caregivers with and without alexithymia. When we examine pain in family members with alexithymia who are caring for cancer patients, we need to recognize that they may set higher personal pain goals and seek less help.
Effect of Inhaled Cannabis for Pain in Adults With Sickle Cell Disease: A Randomized Clinical Trial.
Sickle cell disease (SCD) is characterized by chronic pain and episodic acute pain caused by vasoocclusive crises, often requiring high doses of opioids for prolonged periods. In humanized mouse models of SCD, a synthetic cannabinoid has been found to attenuate both chronic and acute hyperalgesia. The effect of cannabis on chronic pain in adults with SCD is unknown.
The aim of the study is to investigate whether benzodiazepine use differs between patients with favorable and unfavorable spinal cord stimulation (SCS) treatment outcome. We hypothesize that the patients with unfavorable SCS outcome would exhibit a higher level of benzodiazepine use.
The objective was to identify immune alterations in patients with fibromyalgia syndrome (FMS) compared to healthy controls (HC) using meta-analysis and meta-regression. Six electronic databases were searched for suitable original articles investigating immune biomarkers in FMS in comparison to HC. We extracted outcomes and variables of interest, such as mean and SD of peripheral blood immune biomarkers, age or sex. A random-effects model with restricted maximum-likelihood estimator was used to compute effect sizes (standardized mean difference and 95% CI, Hedges' g) and meta-analysis, group meta-analysis and meta-regressions were conducted. Forty-three papers were included in this systematic review, of which 29 were suitable for meta-analysis. Interleukin (IL)-6 (g=0.36 (0.09-0.63); I=85.94; p=0.01), IL-4 (g=0.50 (0.03-0.98); I=81.87; p=0.04), and IL-17A (g=0.53 (0.00-1.06); I=87.15; p=0.05), were significantly higher in FMS compared to HC while also combinations of cytokines into relevant phenotypes were significantly upregulated including M1 macrophage (g=0.23 (0.03-0.43); I=77.62; p=0.02), and immune-regulatory (g=0.40 (0.09-0.72); I=84.81; p=0.01) phenotypes. Heterogeneity levels were very high and subgroup and meta-regression analyses showed that many covariates explained part of the heterogeneity including medication washout, sex, time of blood sampling and exclusion of patients with major depressive disorder. In conclusion, FMS is accompanied by a disbalance between upregulated pro-inflammatory (M1 and Th-17) and immune-regulatory cytokines although effect sizes are small-to-moderate. Based on our results we provide specific methodological suggestions for future research, which should assess Th-1, Th-17, chemokines, and Th-2 phenotypes while controlling for possible confounding variables specified in this study.
Despite the widespread use of spinal cord stimulation (SCS) for chronic pain management, its neuromodulatory effects remain poorly understood. Computational models provide a valuable tool to study SCS and its effects on axonal pathways within the spinal cord. However, these models must include sufficient detail to correlate model predictions with clinical effects, including patient-specific data. Therefore, the goal of this study was to investigate axonal activation at clinically relevant SCS parameters using a computer model that incorporated patient-specific anatomy and electrode locations.