Nrf2 through Aryl Hydrocarbon Receptor Regulates IL-22 Response in CD4+ T Cells.

IL-17A and IL-22 derived from Th17 cells play a significant role in mucosal immunity and inflammation. TGF-ß and IL-6 promote Th17 differentiation; however, these cytokines have multiple targets. The identification and screening of additional molecules that regulate IL-17A and IL-22 responses in certain inflammatory conditions is of great clinical significance. In this study, we show that CDDO-Im, a specific Nrf2 activator, promotes IL-17A and IL-22 responses in murine Th17 cells. In contrast, CDDO-Im inhibits IL-17A response in multiple sclerosis patient-derived PBMCs. However, Nrf2 specifically regulates IL-22 response in vivo. Nrf2 acts through the regulation of antioxidant response element (ARE) binding motifs in target genes to induce or repress transcription. Promoter analysis revealed that Il17a, Rorc, and Ahr genes have several ARE motifs. We showed that Nrf2 bound to ARE repressor (ARE-R2) of Rorc and inhibited Rorc-dependent IL-17A transactivation. The luciferase reporter assay data showed that CDDO-Im regulated Ahr promoter activity. Chromatin immunoprecipitation quantitative PCR data showed that Nrf2 bound to ARE of AhR. Finally, we confirmed that the CDDO-Im-mediated induction of IL-22 production in CD4+ T cells was abrogated in CD4-specific Ahr knockout mice (AhrCD4 ). CH-223191, a specific AhR antagonist, inhibits CDDO-Im-induced IL-22 production in CD4+ T cells, which further confirmed the AhR-dependent regulation. Collectively, our data showed that Nrf2 via AhR pathways regulated IL-22 response in CD4+ T cells.

Treatment of neuromyelitis optica with rituximab: retrospective analysis of 25 patients.

BACKGROUND: Neuromyelitis optica (NMO) is an uncommon, life-threatening inflammatory demyelinating disorder. Recently, much has become known about its immunopathogenesis. However, optimal treatments, with expected outcomes, have not been established. OBJECTIVE: To evaluate the use and efficacy of rituximab for treating NMO. DESIGN: Retrospective multicenter case series of NMO patients treated with rituximab. SETTING: Seven tertiary medical centers in the United States and England. PATIENTS: Twenty-five patients (including 2 children), 23 of whom experienced relapses despite use of other drugs before rituximab. Extended follow-up of 7 previously reported patients is included. INTERVENTIONS: Infusions of rituximab at median intervals of 8 months. MAIN OUTCOME MEASURES: Annualized relapse rate and disability (expressed as Expanded Disability Status Scale score). RESULTS: At a median follow-up of 19 months, the median annualized posttreatment relapse rate was lower than the pretreatment rate (0 [range 0-3.2] vs 1.7 [range, 0.5-5] relapses, P < .001). Disability improved or stabilized in 20 of 25 patients (80%, P = .02). Two patients died during the follow-up period, 1 owing to a brainstem relapse and 1 owing to suspected septicemia. Infections were reported in 20% of patients. CONCLUSIONS: In NMO, treatment with rituximab appears to reduce the frequency of attacks, with subsequent stabilization or improvement in disability.

Treatment of cognitive impairment in multiple sclerosis: is the use of acetylcholinesterase inhibitors a viable option?

Approximately half of all patients with multiple sclerosis (MS) experience cognitive impairment, most commonly with regard to new learning and memory. Cognitive dysfunction is a leading cause of disability in MS and it can have profound social and economic consequences for patients and their families. Research on treatment for cognitive impairment in MS is still in the early stages, as it is for most neurological conditions. The available disease-modifying therapies in MS may provide some modest benefit to cognition, but patients with MS clearly need better treatment for cognitive dysfunction. A number of studies have assessed symptomatic treatments of cognition in MS, and the results of these small, underpowered studies have been mixed. Regardless, acetylcholinesterase inhibitors (AChEIs) have been the most promising class of medications tested in MS to date. Seven of eight studies on AChEIs have shown positive results, although it is difficult to assess their adequacy since only three of the studies have been published in peer reviewed journals, with the rest appearing only as abstracts. The earliest AChEI studies in MS examined physostigmine, but the short half-life and prominent adverse effects of this medication may have limited its use compared with other AChEIs. All of the more recent AChEI studies have used donepezil, which, from the limited data available to date, appears to have been relatively well tolerated among MS patients. The largest randomized controlled trial of donepezil included 69 subjects and found that donepezil improved verbal learning and memory compared with placebo during neuropsychological testing. That study also found that patients receiving donepezil were more likely to report memory improvement than those receiving placebo, and the study clinician also noted a cognitive benefit among those on donepezil as opposed to placebo. There are still many unanswered questions regarding the use of AChEIs in MS, including the effects of their long-term use in a chronic disease such as MS. On the whole, to date the research on AChEIs in MS must be considered preliminary, and it is premature to recommend the clinical use of this class of medications at the present time.