Dectin-2 is predominately macrophage restricted and exhibits conspicuous expression during Aspergillus fumigatus invasion in human lung.

We investigated the features of Dectin-2 expression both at transcriptional and translational levels during Aspergillus fumigatus infection in human lung. Simultaneously, the expression of CD206 was assayed as an activated marker of alveolar macrophages. The characteristic of Dectin-2 expression were then confirmed in Monocyte-derived macrophages (MDM) after A. fumigatus stimulation by Flow Cytometry. We found that the expression of Dectin-2 was low in normal lung, while it revealed a markedly up-regulation during A. fumigatus invasion. Dectin-2 expression was predominantly restricted to CD206 positive cells. There was salient positive correlation between Dectin-2 expression and CD206. We conclude that Dectin-2 expression is largely restricted to alveolar macrophages in human lung. The conspicuous expression of Dectin-2 during A. fumigatus invasion suggests its notable contribution to antifungal defenses in pulmonary aspergillosis.

Effects of Voluntary Attention on Social and Non-Social Emotion Perception.

Existing studies have focused on the effect of emotion on attention, and the role of attention on emotion has largely been underestimated. To further determine the mechanisms underlying the role of attention on emotion, the present study explored the effects of voluntary attention on both social and non-social aspects of emotional perception. Participants were 25 college students who completed the Rapid Serial Visual Prime (RSVP) paradigm. In this study, the selection rates of participants' emotional intensity, pleasure and distinctness perception of the pictures were measured. The results showed as following: (a) The cued condition selection rate was higher than the non-cued condition in the evaluation of non-social emotional intensity perception and pleasure perception, (b) In the evaluation of social emotional intensity and pleasure perception, there was no significant difference in the selection rate between the cued and non-cued condition, (c) The cued condition selection rate was higher than the non-cued condition in the perception of non-social positive emotional intensity and social negative emotional distinctness. The novel findings of this study revealed that the effect of voluntary attention on emotional perception is influenced not only by emotional valence but also by emotional sociality.

Diagnosis of invasive pulmonary fungal infections by a real-time panfungal PCR assay in non-neutropenic patients.

This study explored the utility of quantitative real-time panfungal PCR assay in diagnosing invasive pulmonary fungal diseases (IPFD) in non-neutropenic patients. Panfungal PCR assay was performed on respiratory tract specimens from patients whose clinical signs could not exclude fungal infection. At the same time, the samples were subjected to bacterial and fungal culture, microscopic examination and galactomannan antigen (GM) test in order to find the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the 4 diagnostic methods in proven and probable cases. 518 specimens were collected while 63 respiratory tract specimens tested by PCR had positive results. According to diagnostic criteria, 40 patients were diagnosed with IPFD, with 12 proven, 20 probable and 8 possible cases. Among these, 33 patients of PCR results were positive, most of which were from BALF samples (44.12%). 23 cases were caused by Aspergillus species, with Aspergillus fumigatus was the major cause. Other Aspergillus species, including Aspergillus flavus, Aspergillus terreus and Aspergillus nidulans were found in 1 sample respectively. Candida species were found in 5 samples, Pneumocystis jeroveci pneumonia (PJP) in 4 samples and Mucormycosis in 1 sample. An analysis of proven/probable diagnosis showed a sensitivity of 78.13%, specificity of 92.18%, PPV of 39.68% and NPV of 98.46% for PCR and 50%, 85.27%, 35.7%, 95.65% for GM test respectively. The Ct value difference between proven/probable and possible cases had no statistical significance (P = .824). Fungal culture showed a sensitivity of 17.5% while microscopic examination sensitivity of 32.5%. Through stratified analysis, no apparent correlation was found between the Ct value of the PCR assay and GM value (r: 0.223, P = .294). But a conjunction of the 2 tests raised the PPV of Aspergillus to 90%. As shown in this study, the panfungal RT-PCR assay has high sensitivity and consistency with serological test and culture. Its high PPV in the detection of Aspergillus and PJP were also evident.

The preventative role of curcumin on the lung inflammatory response induced by cardiopulmonary bypass in rats.

BACKGROUND: Acute lung injury is a frequent complication after cardiopulmonary bypass (CPB). Recent studies have reported that NF-κB plays an important role in the pathogenesis of post-CPB pulmonary dysfunction. Several signaling pathways, including the TLR4 pathway, induce NF-κB leading to an inflammatory response. We designed this study to determine whether or not curcumin inhibits TLR4 and MyD88 protein levels and ameliorates lung inflammatory injury in a rat CPB model. MATERIALS AND METHODS: Sprague-Dawley rats were randomly divided into the following five groups (n = 12): sham; control (CPB); vehicle; low-dose curcumin (L-Cur); and high-dose curcumin (H-Cur). The percutaneous beating heart CPB model of rat was established. Animals were pretreated with a single intraperitoneal injection of vehicle, L-Cur (50 mg/kg), or H-Cur (200 mg/kg) 2 h prior to CPB. Blood were sampled at various time points, then lung tissues and bronchoalveolar lavage fluid were harvested 24 h after CPB. RESULTS: CPB induced a marked increase in the concentrations of interleukin-8, tumor necrosis factor-α, and matrix metalloproteinase-9 in plasma, bronchoalveolar lavage fluid, and lung tissues (P < 0.05 versus sham group), whereas curcumin pretreatment reduced these inflammatory markers. Curcumin had effective inhibitory effects on the expression of TLR4, MyD88, and NF-κB in lung tissues 24 h post-CPB (P < 0.05 versus vehicle group). Administration of curcumin remarkably decreased the lung injury score (L-Cur versus vehicle group, P = 0.024; H-Cur versus vehicle group, P = 0.013). CONCLUSIONS: Curcumin may be an alternative therapy for protecting CPB-induced lung injury by suppressing the expression of inflammatory cytokines. This anti-inflammatory effect of curcumin is partly related to the inhibition of TLR4, MyD88, and NF-κB.

[The expressions of nerve growth factor and its tyrosine kinase A receptor on alveolar macrophages in a rat model of chronic obstructive pulmonary disease].

OBJECTIVE: To observe the expressions of nerve growth factor (NGF) and its tyrosine kinase A (TrkA) receptor on alveolar macrophage in a rat model of chronic obstructive pulmonary disease (COPD). METHODS: Forty healthy male SD rats were randomly divided into a control group and a COPD group. The COPD model was established by exposing the rats to cigarette smoke for 6 months, and lung function changes were measured. Lung histopathological changes were detected by HE staining. The expression of NGF protein in the supernatant of alveolar macrophage (AM) culture medium was detected by ELISA. Confocal microscopy was used to identify the separation and purification of AM from bronchoalveolar lavage fluid, and to detect semi-quantitatively the expression of TrkA receptor on AM. NGF and its TrkA receptor at the mRNA level were evaluated by real-time PCR. The differences among groups were calculated by one way ANOVA, and comparison between groups was made by t test. RESULTS: Significant decrease of pulmonary compliance [(0.15 ± 0.03) ml/cm H(2)O (1 cm H2O = 0.098 kPa)] and minute ventilation [(0.045 ± 0.004) L], and significant increase of airway resistance [(0.038 ± 0.004) cm H2O×L(-1)×s(-1)] were found in the COPD group compared with the control group [(0.42 ± 0.05) ml/cm H2O and (0.102 ± 0.010) L and (0.016 ± 0.002) cm H2O×L(-1)×s(-1), t = 9.46 - 12.99, respectively, all P < 0.01]. Alveolar wall thinning, alveolar septa breakdown, alveolar enlargement and emphysema were significant in the COPD rats. The expression of NGF protein in the supernatant of AM culture medium was enhanced in the COPD group [(3.79 ± 1.52) ng/L] compared with the controls [(0.94 ± 0.27) ng/L, t = 4.13, P < 0.05]. Mean fluorescence intensity of TrkA protein on AM in the COPD group (19.5 ± 1.5) was higher than that in the control group (11.2 ± 1.9, t = 7.95, P < 0.05). The expressions of NGF and TrkA at mRNA level in the COPD group (24.8 ± 6.0 and 9.0 ± 3.3) were increased compared with the control group (1.0 ± 0.2 and 1.0 ± 0.4, t = 8.48 and 5.16, all P < 0.05). CONCLUSIONS: The expressions of NGF and its TrkA receptor on AM in COPD group were increased, indicating that NGF and its TrkA receptor might be involved in the pathogenesis of COPD mediated by AM.

Ramelteon Ameliorates LPS-Induced Hyperpermeability of the Blood-Brain Barrier (BBB) by Activating Nrf2.

The blood-brain barrier (BBB) is important for protecting the brain tissue by selectively exchanging substances between the blood and brain. The integrity of the BBB can be damaged by multiple factors, including oxidative stress and inflammation. Ramelteon is an oral hypnotic drug, and in the present study, we investigated its protective effect on BBB damage, as well as the underlying mechanism. LPS was used to induce BBB damage on mice and stimulate injury on endothelial cells. Evans blue staining assay was used to measure the brain permeability. The expressions of ZO-1 and Occludin were evaluated using immunostaining and Western blot in the brain tissue and endothelial cells, respectively. qRT-PCR and ELISA were used to detect the production of IL-1ß and MCP-1 in the brain vessels. TBA assay was utilized to examine the concentration of MDA in the brain tissue and endothelial cells. The expression of Nrf2 in the nucleus and NQO1 were determined using Western blot assay. The endothelial permeability of the monolayer was examined using the FITC-dextran permeation assay. Firstly, the increased brain permeability and downregulated expression of tight junction proteins in the brain tissue induced by LPS were significantly reversed by treatment with Ramelteon, accompanied by the decrease in the production of IL-1ß and MCP-1 in the vessels in mice. Also, the Nrf2 signaling was activated and oxidative stress in the brain vessels was alleviated by treatment with Ramelteon. Secondly, LPS-induced increase in endothelial monolayer permeability and decrease in tight junction protein expression in bEnd.3 brain endothelial cells were significantly reversed by Ramelteon, accompanied by activated Nrf2 signaling and alleviated oxidative stress. Lastly, the protective effects of Ramelteon against LPS-induced reduction of ZO-1 and Occludin, and the increase in endothelial monolayer permeability were dramatically abolished by silencing Nrf2. Ramelteon might ameliorate LPS-induced hyperpermeability of the BBB by activating the Nrf2 signaling pathway.

Deep sequencing profiles MicroRNAs related to Aspergillus fumigatus infection in lung tissues of mice.

BACKGROUND: Invasive pulmonary aspergillosis (IPA) is a severe opportunistic infection with high mortality in patients with compromised immunity. The full repertoire of microRNAs (miRNAs) involved in the regulation of IPA infection remains to be established. METHODS: We established a mouse IPA model and analyzed small RNA transcriptomes in lung tissues of immunodeficient IPA mice (IPA group) and matched immunodeficient control mice (control group) through next-generation sequencing. RESULTS: A total of 3759 known miRNAs were detected, in which 23 miRNAs were identified to be related to IPA. IPA-associated miRNAs include upregulated mmu-let-7b-3p, mmu-miR124-3p, mmu-miR21a-3p, mmu-miR29c-5p, mmu-miR3473b and mmu-miR3473e, and downregulated mmu-miR-150-3p and mmu-miR-503-5p. The expression levels of eight identified miRNAs were quantified in a validation cohort (n = 40) by qRT-PCR, and results revealed the same change patterns. MiRNA target prediction revealed that all IPA-related miRNAs possibly engage a cooperative regulation of key elements in the NF-kappa B signaling pathway. CONCLUSION: We conclude that deep-sequencing small RNAs can uncover miRNA pool-regulating IPA. Our results may lead to further understanding IPA pathogenesis and gain insight into the complexity and diversity of small RNA molecules that regulate immunodeficient IPA.

Brain natriuretic peptide limits myocardial infarct size dependent of nitric oxide synthase in rats.

BACKGROUND: Brain natriuretic peptide (BNP) has recently been shown to have a cardioprotective effect in animal models of myocardial ischemia-reperfusion (I-R) injury. We hypothesized that exogenous BNP limits myocardial infarction on nitric oxide synthase pathway. METHODS: A rat model of myocardial I-R injury was established by ligating the left descending coronary artery for 30 min and then reperfusing for 2 h. BNP was injected with different dose 5 min after the ligation and lasting for 145 min. The myocardial infarct size and the area at risk of ischemia were measured by staining with triphenyltetrazolium chloride (TTC) and Evans blue dye. To examine the role of nitric oxide synthase (NOS), expression of eNOS in the left ventricle was analyzed by western blotting. Nomega-nitro-L-arginine methyl ester (L-NAME; 30 ug/kg), or S-methylisothiourea (SMT; 3 ug/kg) was administrated before I-R with or without BNP. RESULTS: The control infarct-to-risk ratio was 45.1+/-1.72% (means+/-SE). BNP infused 5 min after ischemia limited infarct size in a dosage-dependent manner, with maximal protection observed at 0.01 ug/(kg min) (infarct-to-risk: 24.7+/-1.69%, P<0.01 vs. control), associated with a 10-fold increase of myocardial endothelial nitric oxide synthase above the control value. Protection afforded by BNP was abolished by L-NAME but not by SMT, suggesting the involvement of putative endothelial but not inducible nitric oxide synthase activation. CONCLUSIONS: We conclude that natriuretic peptide/NOS/NO signaling may constitute an important injury-limiting mechanism in myocardium.

Activation of NF-κB and respiratory burst following Aspergillus fumigatus stimulation of macrophages.

Dectin-2, a C-type lectin receptor (CLR), plays an essential role in mediating nuclear factor-kappa B (NF-κB) activation and anti-fungal immunity in response to Candida albicans infection. However, the molecular mechanisms and function of Dectin-2 signaling in response to infection by the pathogenic fungus Aspergillus fumigatus have not been characterized. In order to characterize Dectin-2 signaling in response to A. fumigatus infection, activation of Dectin-2 was analyzed at both transcriptional and translational levels. Spleen tyrosine kinase (Syk) phosphorylation, NF-κB activation and cytokine production downstream of Dectin-2 activation were also investigated. In addition, Dectin-2-Syk function and its ability to mediate reactive oxygen species (ROS) production and elimination of A. fumigatus conidia was examined. We demonstrate that Syk is involved in Dectin-2-induced IκBα (inhibitor of kappa B protein) phosphorylation and NF-κB activation following A. fumigatus stimulation in a time dependent manner. Silencing of Dectin-2 and Syk as well as Syk inhibition blocks NF-κB activation and cytokine secretion. Furthermore, the killing of A. fumigatus conidia and ROS production are significantly affected by Dectin-2 or Syk silencing as well as Syk inhibition. Swelling and germination of the fungus followed by hyphae formation and not the resting and heat-inactivated form of A. fumigatus mediate the activation of Dectin-2 signaling. In conclusion, Syk plays an essential role in IκBα kinase phosphorylation, NF-κB activation, and ROS production mediated by Dectin-2 activation in response to A. fumigatus infection.

Simvastatin attenuates cardiopulmonary bypass-induced myocardial inflammatory injury in rats by activating peroxisome proliferator-activated receptor γ.

Statins have been shown to downregulate the systemic inflammatory response after cardiopulmonary bypass. However, the role of statins as anti-inflammatory agents in heart tissue remains unknown. The aim of this study was to test whether statin pretreatment attenuates local inflammatory cytokines production in heart and to explore whether the underlying mechanism involves peroxisome proliferator-activated receptor (PPAR) γ. A rat model of cardiopulmonary bypass was established. The animals were pretreated with simvastatin 5 mg/kg/day or 10 mg/kg/day for 7 days before operation. The serum concentration and myocardial level of tumor necrosis factor (TNF)-α, interleukin (IL)-6, monocyte chemoattractant protein (MCP)-1 was evaluated by enzyme linked immunosorbent assay. The polymorphonuclear neutrophils accumulation in heart tissue was determined by myeloperoxidase activity assay. The activity of nuclear factor (NF)-κB and PPARγ in the heart was determined by electrophoretic mobility shift assay. The myocardial PPARγ expression was also examined by immunohistochemistry. The systemic and local TNF-α, IL-6 and MCP-1 were all significantly elevated after cardiopulmonary bypass. In contrast, simvastatin pretreatment significantly decreases the serum and myocardial expression level of above cytokines, myocardial myeloperoxidase activity and myocardial NF-κB activity. However, there was an evident increase in the activity and expression of PPARγ. In conclusion, simvastatin pretreatment not only attenuates acute systemic and local inflammatory response induced by cardiopulmonary bypass. The anti-inflammatory effect of simvastatin in myocardium may be partly related to the activation of PPARγ and inhibition of NF-κB.

Inhibition of chemokine receptor CCR2 and CCR5 expression contributes to simvastatin-induced attenuation of cardiac allograft vasculopathy.

BACKGROUND: Accumulating evidence reveals that statins possess pleiotropic properties beyond cholesterol reduction, which may contribute to the attenuation of cardiac allograft vasculopathy (CAV). Recent in vitro data suggest that statins could down-regulate chemokine receptors. This study was designed to test the hypothesis that simvastatin ameliorates CAV development via the inhibition of chemokine receptor expression in an inbred rat model of cardiac transplantation. METHODS: Animals were divided into four groups: isograft; control (cyclosporine [CsA] + vehicle); low-dose simvastatin (LSIM; CsA + 5 mg/kg simvastatin); and high-dose simvastatin (HSIM; CsA + 10 mg/kg simvastatin). Donor hearts from Fisher 344 rats were transplanted heterotopically into Lewis rat recipients. CsA was administered at 1.5 mg/kg/day for 2 weeks post-operatively. In addition, recipients were treated daily with simvastatin or vehicle for 8 weeks. Donor hearts were harvested for histopathologic and immunohistochemical examination. Intragraft concentration of chemokines and chemokine receptor expression were analyzed using enzyme-linked immunosorbent assay and quantitative real-time polymerase chain reaction, respectively. RESULTS: Both low and high doses of simvastatin significantly decreased the CAV score; inhibited recruitment of T lymphocytes and macrophages; reduced levels of intragraft MCP-1 (monocyte chemoattractant protein-1), RANTES (regulated on activation, normal T-cell expressed and secreted) protein and IP-10 (interferon-inducible protein-10); and down-regulated expression of chemokine receptors CCR2 and CCR5. CXCR3 expression was not affected by simvastatin treatment. CONCLUSIONS: Our results demonstrate that simvastatin may attenuate CAV development, possibly through retarding intragraft chemokine accumulation and chemokine receptor expression.

Simvastatin suppresses lung inflammatory response in a rat cardiopulmonary bypass model.

BACKGROUND: Inflammatory response in the lungs is a well-known complication after cardiopulmonary bypass (CPB). The main aims of our study were to explore whether pretreatment with simvastatin would inhibit toll-like receptor 4 expression and suppress lung inflammatory response in a rat CPB model. METHODS: Male Sprague-Dawley rats were divided into four groups (n = 6 each): sham group; CPB (control group); CPB plus low-dose simvastatin (5 mg/kg daily [L-Sim group]); and CPB plus high-dose simvastatin (10 mg/kg daily [H-Sim group]). Blood samples were collected at the beginning and at the termination of CPB, and at 1, 2, 4, and 24 hours after operation. The bronchoalveolar lavage fluid and lungs were harvested 24 hours postoperatively. RESULTS: The simvastatin-treated groups had significantly higher ratios of PaO(2)/FiO(2) and lower values of respiratory index than the control group. We observed that simvastatin reduced CPB-induced toll-like receptor 4 and nuclear factor-kappaB expressions in CPB groups (p < 0.01, versus control group). The levels of interleukin-6, tumor necrosis factor-alpha, and monocyte chemotactic protein-1 in serum, bronchoalveolar lavage fluid, and lung tissues increased in CPB groups, whereas pretreatment with simvastatins reduced these inflammatory marks in a dose-dependent manner (p < 0.01, versus control group). Furthermore, pretreatment with simvastatin had a lower lung injury score (p < 0.05, versus control group). CONCLUSIONS: These findings suggest that simvastatin inhibited CPB-induced toll-like receptor 4 upregulation and nuclear factor-kappaB activation, efficaciously reduing the pulmonary inflammatory response after CPB.

N-acetylcysteine to ameliorate acute renal injury in a rat cardiopulmonary bypass model.

OBJECTIVE: Oxidative stress and systemic inflammation response contribute to acute renal injury post cardiac surgery. We hypothesized that administration of the antioxidant N-acetylcysteine would be beneficial to renal function after cardiopulmonary bypass in a rat model. METHODS: Male Sprague-Dawley rats were divided into four groups (each n = 6): sham group, cardiopulmonary bypass group, and two N-acetylcysteine-treated cardiopulmonary bypass groups (bolus doses of 200 and 500 mg/kg in cardiopulmonary bypass prime). Blood samples were collected at the beginning of cardiopulmonary bypass, at the cessation of cardiopulmonary bypass, and at 2 and 12 postoperative hours. The kidneys were harvested at 12 postoperative hours. RESULTS: Serum creatinine and cystatin C continuously increased in all cardiopulmonary bypass groups (P < .05 within groups). Tubular dilatation, tubular necrosis, and vacuole formation were found in epithelial cells in histomorphologic studies of the cardiopulmonary bypass groups, but N-acetylcysteine significantly reversed these effects (P < .05 between groups). Compared with the sham group, the reduced glutathione hormone content and the superoxide dismutase and catalase activities decreased in the cardiopulmonary bypass groups (P < .01). N-acetylcysteine-treated groups had higher levels of these antioxidants than the untreated bypass group (P < .05). Renal malondialdehyde, tumor necrosis factor alpha, and nuclear factor kappaB were notably increased in all cardiopulmonary bypass groups relative to the sham group (P < .01), and N-acetylcysteine attenuated these changes dose dependently. CONCLUSION: Administration of the antioxidant N-acetylcysteine preserved renal function after cardiopulmonary bypass dose dependently. Furthermore, oxidative stress and systemic inflammation were significantly reduced in the treated animals.