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High-fat diet (HFD) induces low-grade chronic inflammation and insulin resistance. However, little is known about the mechanism underlying HFD-induced chronic inflammation in peripheral insulin-responsive tissues. Here, we show that colonic pro-inflammatory macrophages regulate insulin sensitivity under HFD conditions. To investigate the pathophysiological role of colonic macrophages, we generated macrophage-specific chemokine (C-C Motif) receptor 2 (Ccr2) knockout (M-Ccr2KO) and intestinal epithelial cell-specific tamoxifen-inducible Ccl2 knockout (Vil-Ccl2KO) mice. Both strains exhibited similar body weight to control under HFD. However, they exhibited decreased infiltration of colonic pro-inflammatory macrophages, decreased intestinal permeability, and inactivation of the colonic inflammasome. Interestingly, they showed significantly improved glucose tolerance and insulin sensitivity with decreased chronic inflammation of adipose tissue. Therefore, inhibition of pro-inflammatory macrophage infiltration prevents HFD-induced insulin resistance and could be a novel therapeutic approach for type 2 diabetes., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Chronic granulomatous disease (CGD) is a rare inherited disorder characterized by an inability to produce reactive oxygen species, resulting in recurrent life-threatening infections. Curiously, half of the patients with CGD suffer from aseptic bowel inflammation (CGD colitis) due to dysregulated inflammation induced by TNF-α and IL-1β. Thus, developing therapies that regulate excessive inflammatory responses without interrupting antimicrobial immunity would benefit CGD colitis patients. Here, we show that thalidomide suppressed TNF-α-induced NF-κB activation and ATP-induced IL-1β secretion, but did not interrupt the production of IL-1β, IL-6, IL-8, and TNF-α in response to lipopolysaccharide in CGD monocytes. We report on a CGD colitis patient that showed decreased bowel inflammation characterized by reduced serum levels of inflammatory cytokines without evidence of progression of fungal and bacterial infections present at initiation of thalidomide therapy. Our results suggest that thalidomide could be an efficacious therapeutic option for patients with CGD colitis suffering from serious infections., (Copyright © 2013 Elsevier Inc. All rights reserved.)

The article presents a case study of a 7-month-old boy who developed intractable impetigo and inguinal lymphadenitis during the neonatal period. Pediatric Ulcerative Colitis Activity Index (PUCAI) has been validated and is commonly used for pediatric ulcerative colitis (UC), to measure disease activity based on the clinical manifestations of aseptic granulomatous colitis (AGC) in chronic granulomatous disease (CGD) patients.

Purpose: Chronic granulomatous disease (CGD) is a primary immunodeficiency disease that leads to recurrent infection and hyper-inflammation, occasionally represented by CGD-associated colitis (CGD colitis). Although clinical symptoms of CGD colitis mimic those of ulcerative colitis (UC), there is no reliable standard measurement of disease activity or standard therapeutic strategy for CGD colitis. Here, we examined the clinical manifestation of CGD colitis based on severity using a noninvasive measure of disease activity, the Pediatric Ulcerative Colitis Activity Index (PUCAI), which has been validated and widely used for pediatric UC. Methods: Sixteen of 35 CGD patients, who were diagnosed with CGD colitis based on colonoscopic and histological findings, were examined using the PUCAI. Both the PUCAI and the physician global assessment (PGA) tool were retrospectively scored by reviewing medical records. Results: Disease activity defined by PUCAI was correlated with PGA, and increased at diagnosis of CGD colitis, especially in patients who were younger than 6 years of age (very early-onset CGD colitis: VEO-CGD colitis) when diagnosed with CGD colitis. All severe patients had a more progressive form of VEO-CGD colitis. Unlike mild and moderate patients, severe patients required multidrug therapy of corticosteroids and immunomodulator/immunosuppressants, and some were eventually treated with hematopoietic stem cell transplantation. Conclusions: Although the validation of PUCAI in CGD colitis should be considered for future use, our results indicate that noninvasive measures could be effective to measure disease activity and help to determine suitable treatment for CGD colitis. In patients with VEO-CGD colitis, multidrug therapy would need to be considered at an early stage on the basis of disease activity. [ABSTRACT FROM AUTHOR]

Chronic inflammation in adipose tissue contributes to obesity-related insulin resistance. The 3-phosphoinositide-dependent protein kinase 1 (Pdk1)/forkhead transcription factor (Foxo1) pathway is important in regulating glucose and energy homeostasis, but little is known about this pathway in adipose tissue macrophages (ATMs). To investigate this, we generated transgenic mice that carried macrophage/granulocyte-specific mutations, including a Pdk1 knockout (LysMPdk1-/-), a Pdk1 knockout with transactivation-defective Foxo1 (Δ256LysMPdk1-/-), a constitutively active nuclear (CN) Foxo1 (CNFoxo1LysM), or a transactivation-defective Foxo1 (D256Foxo1LysM). We analyzed glucose metabolism and gene expression in ATM populations isolated with fluorescence-activated cell sorting. The LysMPdk1-/- mice exhibited elevated M1 macrophages in adipose tissue and insulin resistance. Overexpression of transactivation-defective Foxo1 rescued these phenotypes. CNFoxo1LysM promoted transcription of the C-C motif chemokine receptor 2 (Ccr2) in ATMs and increased M1 macrophages in adipose tissue. On a high-fat diet, CNFoxo1LysM mice exhibited insulin resistance. Pdk1 deletion or Foxo1 activation in bone marrow-derived macrophages abolished insulin and interleukin-4 induction of genes involved in alternative macrophage activation. Thus, Pdk1 regulated macrophage in filtration by inhibiting Foxo1-induced Ccr2 expression. This shows that the macrophage Pdk1/Foxo1 pathway is important in regulating insulin sensitivity in vivo. [ABSTRACT FROM AUTHOR]