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Chronic inflammation underlies the pathological progression of various diseases, and thus many efforts have been made to quantitatively evaluate the inflammatory status of the diseases. In this study, we generated a highly sensitive inflammation-monitoring mouse system using a bacterial artificial chromosome (BAC) clone containing extended flanking sequences of the human interleukin 6 gene (hIL6) locus, in which the luciferase (Luc) reporter gene is integrated (hIL6-BAC-Luc).We successfully monitored lipopolysaccharide-induced systemic inflammation in various tissues of the hIL6-BAC-Lucmice using an in vivo bioluminescence imaging system. When two chronic inflammatory disease models, i.e., a genetic model of atopic dermatitis and a model of experimental autoimmune encephalomyelitis (EAE), were applied to the hIL6-BAC-Lucmice, luciferase bioluminescence was specifically detected in the atopic skin lesion and central nervous system, respectively. Moreover, the Luc activities correlated well with the disease severity. Nrf2 is a master transcription factor that regulates antioxidative and detoxification enzyme genes. Upon EAE induction, the Nrf2-deficient mice crossed with the hIL6-BAC-Luc mice exhibited enhanced neurological symptoms concomitantly with robust luciferase luminescence in the neuronal tissue. Thus, whole-body in vivo monitoring using the hIL6BAC-Luc transgenic system(WIM-6 system) provides a new and powerful diagnostic tool for real-time in vivo monitoring of inflammatory status in multiple different disease models. [ABSTRACT FROM AUTHOR]

Loss-of-function mutations in KEAP1 frequently occur in lung cancer and are associated with poor prognosis and resistance to standard of care treatment, highlighting the need for the development of targeted therapies. We previously showed that KEAP1 mutant tumors consume glutamine to support the metabolic rewiring associated with NRF2-dependent antioxidant production. Here, using preclinical patient-derived xenograft models and antigenic orthotopic lung cancer models, we show that the glutamine antagonist prodrug DRP-104 impairs the growth of KEAP1 mutant tumors. We find that DRP-104 suppresses KEAP1 mutant tumors by inhibiting glutamine-dependent nucleotide synthesis and promoting antitumor T cell responses. Using multimodal single-cell sequencing and ex vivo functional assays, we demonstrate that DRP-104 reverses T cell exhaustion, decreases Tregs, and enhances the function of CD4 and CD8 T cells, culminating in an improved response to anti-PD1 therapy. Our preclinical findings provide compelling evidence that DRP-104, currently in clinical trials, offers a promising therapeutic approach for treating patients with KEAP1 mutant lung cancer. [ABSTRACT FROM AUTHOR]

Acute kidney injury (AKI) is a leading cause of chronic kidney disease. Proximal tubules are considered to be the primary origin of pathogenic inflammatory cytokines in AKI. However, it remains unclear whether other cell types, including collecting duct (CD) cells, participate in inflammatory processes. The transcription factor GATA2 is specifically expressed in CD cells and maintains their cellular identity. To explore the pathophysiological function of GATA2 in AKI, we generated renal tubular cell-specific Gata2 deletion (G2CKO) mice and examined their susceptibility to ischemia reperfusion injury (IRI). Notably, G2CKO mice exhibited less severe kidney damage, with reduced granulomacrophagic infiltration upon IRI. Transcriptome analysis revealed that a series of inflammatory cytokine genes were downregulated in GATA2-deficient CD cells, suggesting that GATA2 induces inflammatory cytokine expression in diseased kidney CD cells. Through high-throughput chemical library screening, we identified a potent GATA inhibitor. The chemical reduces cytokine production in CD cells and protects the mouse kidney from IRI. These results revealed a novel pathological mechanism of renal IRI, namely, that CD cells produce inflammatory cytokines and promote IRI progression. In injured kidney CD cells, GATA2 exerts a proinflammatory function by upregulating inflammatory cytokine gene expression. GATA2 can therefore be considered a therapeutic target for AKI. [ABSTRACT FROM AUTHOR]

The transcription factor NF-E2-related factor 2 (Nrf2) is a key regulator of cellular defense mechanisms against oxidative stress. Multiple sclerosis (MS), a chronic inflammatory disease of the central nervous system, is characterized by progressive demyelination and neurodegeneration induced by inflammation and oxidative stress. The induction of Nrf2 signaling has been shown to inhibit disease development and progression in the experimental autoimmune encephalomyelitis (EAE) model of MS in mice. In the present study, we performed a high-throughput screening assay using a chimeric construct of the N-terminal portion of Nrf2 fused to LacZ. Using this approach, we identified the novel Nrf2 inducer TFM-735. Using human primary cell profiling systems, we found that TFM-735 inhibited T cell proliferation and exerted immuno-modulatory effects by inhibiting the production of IL-6 and IL-17. TFM-735 also inhibited IL-17 secretion from human peripheral blood mononuclear cells stimulated with anti-CD3 and anti-CD28. In EAE mice treated with TFM-735, the expression of the Nrf2 target gene Nqo1 increased in the brain and spleen, disease severity was ameliorated, and plasma IL-17 levels decreased. Furthermore, TFM-735 inhibited luciferase activity in Wim-6 transgenic EAE mice expressing the human interleukin 6-luciferase (hIL6-BAC-Luc) reporter. Therefore, these findings indicate that TFM-735 is a potent Nrf2 inducer that inhibits inflammatory cytokine production and disease progression in mice with EAE and that TFM-735 is a promising therapeutic agent for MS. [ABSTRACT FROM AUTHOR]

Sickle cell disease (SCD) is an inherited disorder caused by a point mutation in the β-globin gene, leading to the production of abnormally shaped red blood cells. Sickle cells are prone to hemolysis and thereby release free heme into plasma, causing oxidative stress and inflammation that in turn result in damage to multiple organs. The transcription factor Nrf2 (nuclear factor erythroid 2-related factor 2) is a master regulator of the antioxidant cell-defense system. Here we show that constitutive Nrf2 activation by ablation of its negative regulator Keap1 (kelch-like ECH-associated protein 1) significantly improves symptoms in SCD model mice. SCD mice exhibit severe liver damage and lung inflammation associated with high expression levels of proinflammatory cytokines and adhesion molecules compared with normal mice. Importantly, these symptoms subsided after Nrf2 activation. Although hemolysis and stress erythropoiesis did not change substantially in the Nrf2-activated SCD mice, Nrf2 promoted the elimination of plasma heme released by sickle cells' hemolysis and thereby reduced oxidative stress and inflammation, demonstrating that Nrf2 activation reduces organ damage and segregates inflammation from prevention of hemolysis in SCD mice. Furthermore, administration of the Nrf2 inducer CDDO-Im (2-cyano-3,12 dioxooleana-1,9 diene-28-imidazolide) also relieved inflammation and organ failure in SCD mice. These results support the contention that Nrf2 induction may be an important means to protect organs from the patho-physiology of sickle cell-induced damage. [ABSTRACT FROM AUTHOR]

GATA1 is a key transcription factor for erythropoiesis. GATA1 gene expression is strictly regulated at the transcriptional level. While the regulatory mechanisms governing mouse Gata1 (mGata1) gene expression have been studied extensively, how expression of the human GATA1 (hGATA1) gene is regulated remains to be elucidated. To address this issue, we generated hGATA1 bacterial artificial chromosome (BAC) transgenic mouse lines harboring a 183-kb hGATA1 locus covering the hGATA1 exons and distal flanking sequences. Transgenic hGATA1 expression coincides with endogenous mGata1 expression and fully rescues hematopoietic deficiency in mGata1 knockdown mice. The transgene exhibited copy number-dependent and integration position- independent expression of hGATA1, indicating the presence of chromatin insulator activity within the transgene. We found a novel insulator element at 29 kb 5' to the hGATA1 gene and refer to this element as the 5' CCCTC-binding factor (CTCF) site. Substitution mutation of the 5' CTCF site in the hGATA1 BAC disrupted the chromatin architecture and led to a reduction of hGATA1 expression in splenic erythroblasts under conditions of stress erythropoiesis. Our results demonstrate that expression of the hGATA1 gene is regulated through the chromatin architecture organized by 5' CTCF site-mediated intrachromosomal interactions in the hGATA1 locus. [ABSTRACT FROM AUTHOR]

We evaluated a hypothesis that thrombus aspiration with distal protection is superior to simple thrombus aspiration in patients treated with primary percutaneous coronary intervention (PCI). A total of 176 consecutive patients with ST-segment elevation myocardial infarction were enrolled in this study and assigned to either the thrombus aspiration group (A, n = 104) or the thrombus aspiration with distal protection group using a filter device system (A + DP, n = 72). We compared the angiographic reperfusion grade, left ventricular (LV) function, and clinical outcomes between the 2 groups. There were no significant differences in age, gender distribution, the onset-to-reperfusion time, the peak levels of creatine kinase, or 6-month mortality between the 2 groups. The rate of achieving a Thrombolysis In Myocardial Infarction flow grade of 3 and a myocardial blush grade of 3 was higher in the A + DP group than in the A group. Among the patients who underwent follow-up catheterization 6 months after PCI (A, n = 62; A + DP, n = 52), there were no significant differences in the LV end-diastolic volume index, LV end-systolic volume index, or LV ejection fraction between the 2 groups at the time of PCI or 6 months after PCI. In conclusion, thrombus aspiration with distal protection may be more effective in initially restoring the coronary blood flow than thrombus aspiration alone, although it may not be superior to thrombus aspiration in preventing LV remodeling or preserving the LV function in patients with ST-segment elevation myocardial infarction. [ABSTRACT FROM AUTHOR]