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A bdominal aortic aneurysm (AAA) is an age-related disease that occurs in ≤9% of adults aged of ≥65 years and is responsible for a significant number of deaths in Western countries.1 Although aggressive management of hypertension and hyperlipidemia is recommended in patients with AAA, these strategies have only little effect on the progression of AAA. Surgery is the only treatment for patients with AAA, but this is costly and associated with high morbidity and mortality.2 Endovascular repair is associated with lower postoperative mortality rates as compared to open surgical repair; however, there are no significant differences in total mortality or AAA-related mortality in the long term, with a higher incidence of reintervention in endovascular repair.3 When surgical treatment is not possible, AAAs typically progress to rupture with high mortality primarily because no effective nonsurgical treatment is currently available. Thus, a better understanding of the underlying mechanisms involved in AAA formation may help in identifying new therapeutic targets that could suppress AAA progression and reduce the risk of rupture.© 2014 American Heart Association, Inc. Objective-Abdominal aortic aneurysm (AAA) is considered a chronic inflammatory disease; however, the molecular basis underlying the sterile inflammatory response involved in the process of AAA remains unclear. We previously showed that the inflammasome, which regulates the caspase-1-dependent interleukin-1β production, mediates the sterile cardiovascular inflammatory responses. Therefore, we hypothesized that the inflammasome is a key mediator of initial inflammation in AAA formation. Approach and Results-Apoptosis-associated speck-like protein containing a caspase recruitment domain is highly expressed in adventitial macrophages in human and murine AAA tissues. Using an established mouse model of AAA induced by continuous infusion of angiotensin II in Apoe -/-mice, NLR family pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein containing a caspase recruitment domain, and caspase-1 deficiency in Apoe -/-mice were shown to decrease the incidence, maximal diameter, and severity of AAA along with adventitial fibrosis and inflammatory responses significantly, such as inflammatory cell infiltration and cytokine expression in the vessel wall. NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain, and caspase-1 deficiency in Apoe -/-mice also reduced elastic lamina degradation and metalloproteinase activation in the early phase of AAA formation. Furthermore, angiotensin II stimulated generation of mitochondria-derived reactive oxygen species in the adventitial macrophages, and this mitochondria-derived reactive oxygen species generation was inhibited by NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain, and caspase-1 deficiency. In vitro experiments revealed that angiotensin II stimulated the NLRP3 inflammasome activation and subsequent interleukin-1β release in macrophages,...

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Inflammation plays a key role in the pathophysiology of hepatic ischemia–reperfusion (I/R) injury. However, the mechanism by which hepatic I/R induces inflammatory responses remains unclear. Recent evidence indicates that a sterile inflammatory response triggered by I/R is mediated through a multiple-protein complex called the inflammasome. Therefore, we investigated the role of the inflammasome in hepatic I/R injury and found that hepatic I/R stimuli upregulated the inflammasome-component molecule, nucleotide-binding oligomerization domain–like receptor (NLR) family pyrin domain–containing 3 (NLRP3), but not apoptosis-associated speck–like protein containing a caspase recruitment domain (ASC). NLRP3−/− mice, but not ASC−/− and caspase-1−/− mice, had significantly less liver injury after hepatic I/R. NLRP3−/− mice showed reduced inflammatory responses, reactive oxygen species production, and apoptosis in I/R liver. Notably, infiltration of neutrophils, but not macrophages, was markedly inhibited in the I/R liver of NLRP3−/− mice. Bone marrow transplantation experiments showed that NLRP3 not only in bone marrow–derived cells, but also in non-bone marrow–derived cells contributed to liver injury after I/R. In vitro experiments revealed that keratinocyte-derived chemokine–induced activation of heterotrimeric G proteins was markedly diminished. Furthermore, NLRP3−/− neutrophils decreased keratinocyte-derived chemokine–induced concentrations of intracellular calcium elevation, Rac activation, and actin assembly formation, thereby resulting in impaired migration activity. Taken together, NLRP3 regulates chemokine-mediated functions and recruitment of neutrophils, and thereby contributes to hepatic I/R injury independently of inflammasomes. These findings identify a novel role of NLRP3 in the pathophysiology of hepatic I/R injury.

These findings demonstrate that excess SFAs cause intracellular crystallization and subsequent lysosomal dysfunction, leading to the activation of the NLRP3 inflammasome, and provide novel insights into the pathogenesis of metabolic diseases.

Abstract. In cows, interferon-tau (IFNT) regulates maternal recognition around days 15-19 after artificial insemination (AI). The present study hypothesized that if key target genes of IFNT are clearly upregulated in earlier stages of pregnancy, these genes could be use as indices of future pregnancy in cows. Therefore, we determined the expression of these genes in peripheral blood mononuclear leukocytes (PBMCs) and polymorphonuclear granulocytes (PMNs) during the maternal recognition period (MRP). Twenty multiparous Holstein cows were subjected to AI on day 0 and categorized into the following groups: pregnancy (Preg, n = 9), embryonic death (ED, n = 5) and non-pregnancy (NP, n = 6). Progesterone levels in the Preg group were higher than those in the NP group on days 12-21. ISG15 and OAS-1 (IFN-stimulated genes: ISGs) mRNA in PBMCs on day 8 was higher in the Preg group than in the NP group, and these mRNAs in PMNs was higher in the Preg group on day 5 than in the NP and ED groups. Interleukin-10 (IL-10, Th2 cytokine) mRNA expression increased on day 8 in the PBMCs of pregnant cows. Tumor necrosis factor α (TNFα, Th1 cytokine) mRNA expression was stable in all groups. In an in vitro cell culture experiment, IFNT stimulated mRNA expression of ISGs in both PBMCs and PMNs. IFNT stimulated IL-10 mRNA expression in PBMCs, whereas IFNT increased TNFα mRNA levels in PBMCs in vitro. The results suggest that ISGs and IL-10 could be responsive to IFNT before the MRP in peripheral blood immune cells and may be useful target genes for reliable indices of pregnancy before the MRP. Key words: Cow, Immune cells, Interferon tau, Pregnancy (J. Reprod. Dev. 58: [84][85][86][87][88][89][90] 2012) D uring the past 5 decades, milk production per cow has dramatically increased because of improved management, nutrition, and genetic selection [1,2]. In contrast, the decreases in fertility and conception rates of the modern high-producing dairy cow are the major causes of economic loss for dairy producers [2,3]. After establishment of pregnancy in domestic ruminants, the conceptus secretes interferon-tau (IFNT) as a maternal recognition factor [4]. IFNT acts in the uterus around day 16 after insemination and prevents luteolysis by inhibiting prostaglandin F 2α release, resulting in the maintenance of corpus luteum function; therefore, this period is termed the maternal recognition period (MRP) [5]. IFNT induces the synthesis and secretion of IFN-stimulated genes (ISGs) such as ISG15, 2′,5′-oligoadenylate synthetase (OAS-1), IFN regulatory factor 1, Mx1 and Mx2 not only in the uterus but also in blood cells in ewes and cows [6][7][8][9][10]. In fact, in bovine peripheral blood leukocytes, ISG15 mRNA levels were higher in pregnant cows than in nonpregnant cows on days 18 and 20 after artificial insemination (AI) [7][8][9]. Technology for the early detection of pregnancy is needed to identify nonpregnant cows and to synchronize and artificially inseminate these cows prior to the next ovulation, and many studies have focused on identify...

BackgroundAfter ovulation in the cow, the corpus luteum (CL) rapidly develops within a few days with angiogenesis and progesterone production. CL formation resembles an inflammatory response due to the influx of immune cells. Neutrophils play a role in host defense and inflammation, and secrete chemoattractants to stimulate angiogenesis. We therefore hypothesized that neutrophils infiltrate in the developing CL from just after ovulation and may play a role in angiogenesis of the CL.Methods and ResultsPolymorphonuclear neutrophils (PMN) were detected in CL tissue by Pas-staining, and interleukin-8 (IL-8, a neutrophil-specific chemoattractant) was measured in supernatant of the CL tissue culture: considerable amounts of PMNs and the high level of IL-8 were observed during the early luteal phase (days 1-4 of the estrous cycle). PMNs and IL-8 were low levels in the mid and late luteal phases, but IL-8 was increased during luteal regression. The PMN migration in vitro was stimulated by the supernatant from the early CL but not from the mid CL, and this activity was inhibited by neutralizing with an anti-IL-8 antibody, indicating the major role of IL-8 in inducing active PMN migration in the early CL. Moreover, IL-8 stimulated proliferation of CL-derived endothelial cells (LECs), and both the supernatant of activated PMNs and IL-8 stimulated formation of capillary-like structures of LECs.ConclusionPMNs migrate into the early CL partially due to its major chemoattractant IL-8 produced at high levels in the CL, and PMNs is a potential regulator of angiogenesis together with IL-8 in developing CL in the cow.

Active angiogenesis and progesterone (P) synthesis occur in parallel during development of the corpus luteum (CL). Basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) are known to stimulate angiogenesis and P synthesis in vitro. The aim of the present study was to investigate the impact of bFGF or VEGF on the CL development in the cow by using a specific antibody against bFGF or VEGF. bFGF antibody, VEGF antibody, or saline as a control (n = 4 cows/treatment) were injected directly into the CL immediately after ovulation (Day 1), and the treatment was continued for 3 times/day over 7 days. Luteal biopsies were applied on Day 8 of the estrous cycle to determine the expression of genes associated with P synthesis and angiogenesis. Intraluteal injections with the bFGF antibody or the VEGF antibody markedly decreased the CL volume, plasma P concentration and StAR mRNA expression. bFGF antibody treatment decreased the mRNA expression of bFGF, FGF receptor-1, VEGF120, and angiopoietin (ANPT)-1, and increased ANPT-2/ANPT-1 ratio. However, VEGF antibody treatment decreased ANPT-2 mRNA expression and ANPT-2/ANPT-1 ratio. These results indicate that local neutralization of bFGF or VEGF changes genes regulating angiogenesis and P synthesis, and remarkably suppresses the CL size and P secretion during the development of CL in the cow, supporting the concept that bFGF and VEGF control the CL formation and function.