The incidence of
infection and the rate of resistance to antifungal drugs have sharply increased in recent years. LL37 has been reported as a host defense peptide with broad-spectrum antibacterial ...activities. However, the role of LL37 during
infection remains unclear. Here, we examined the interaction between LL37 and
and found that synthetic LL37 could directly bind to the surface of
, disrupting the integrity of the cell wall
. LL37 inhibited mycelial growth in a concentration-dependent manner, rather than fungicidal effect even at high concentration (e.g., 20 μM). Interestingly, low concentrations of LL37 (e.g., 4 μM) significantly attenuated mycelial adhesion and prevented the invasion and destruction of epithelial cells. Following LL37 treatment, the levels of proinflammatory cytokines released by
-stimulated macrophages decreased significantly, accompanied by downregulation of M1 type markers. In a mouse model of pulmonary
infection, LL37-treated mice showed lower amounts of fungi load, moderate pathological damage, and reduced proinflammatory cytokines. Further, LL37 transgenic mice (LL37+/+) were examined to investigate the effects of endogenous LL37 in an
infection model and showed lower susceptibility to
infection in comparison with wild-type mice. In addition, LL37 also played a protective role in an immunosuppressed mouse model of
infection. Thus, LL37 inhibits
infection via directly binding to mycelia and reducing excessive inflammation. LL37 or its analogs may therefore constitute potential drug components for
infection.
•PM2.5 inhibits activation of NLRP3 inflammasome induced by LPS combined with H1N1 PR8 infection.•AHR-TIPARP axis mediates the role of PM2.5 in suppressing expression of type I interferon induced by ...influenza virus.•PM2.5 increases the susceptibility of H1N1 virus infection in vivo.
PM2.5, a major component of air pollutants, has caused severe health problems. It has been reported that PM2.5 index is closely associated with severity of influenza A virus (IAV) infection. However, the underlying mechanisms have not been addressed. NLRP3 inflammasome and type I interferon signaling regulate host defense against influenza infection. The present study investigated the potential effects of air pollutants on host defense against influenza infection in vitro and in vivo. In this study, different concentrations of PM2.5 were pre-exposed to macrophages and mice before IAV infection to assess the negative effects of air pollutants in virus infection. We found that exposure to PM2.5 deteriorated influenza virus infection via compromising innate immune responses manifested by a decrease IL-1β and IFN-β production in vitro. Meanwhile, mice exposed with PM2.5 were susceptible to PR8 virus infection due to down-regulation of IL-1β and IFN-β. Mechanistically, PM 2.5 exposure suppressed the NLRP3 inflammasome activation and the AHR-TIPARP signaling pathway, by which compromised the anti-influenza immunity. Thus, our study revealed that PM2.5 could alter macrophage inflammatory responses by suppressing LPS-induced activation of NLRP3 inflammasome and expression of IFN-β during influenza infection. These findings provided us new insights in understanding that PM2.5 combining with influenza infection could enhance the severity of pneumonia.
Chronic obstructive pulmonary disease (COPD) is one of the most common comorbidities in community acquired pneumonia (CAP) patients. We aimed to investigate the characteristics and mortality risk ...factors of COPD patients hospitalized with CAP.
A retrospective cohort study was conducted at Shanghai Pulmonary Hospital and Shanghai Dahua Hospital. Clinical and demographic data in patients diagnosed with CAP were collected between January 2015 and June 2016. Logistic regression analysis was performed to screen mortality risk factors of COPD patients hospitalized with CAP.
Of the total 520 CAP patients, 230 (44.2%) patients had been diagnosed comorbid with COPD (COPD-CAP). CAP patients comorbid with COPD patients had higher rate of need for ICU admission (18.3% vs 13.1%) and need for NIMV (26.1% vs 1.4%) than without COPD (nCOPD-CAP). The PSI, CURB-65 and APACHE-II scores in COPD-CAP patients were higher than that in nCOPD-CAP patients (95 vs 79, P < 0.001; 1 vs 1, P < 0.001; 13 vs 8, P < 0.001, respectively). Logistic regression analysis indicated that aspiration, D-dimer > 2.0 μg/mL and CURB-65 ≥ 3 were risk factors associated with in-hospital mortality ((odd ratio) OR = 5.678, OR = 4.268, OR = 20.764, respectively) in COPD-CAP patients. The risk factors associated with 60-day mortality in COPD-CAP patients were comorbid with coronary heart disease, aspiration, need for NIMV (non-invasive mechanical ventilation) and CURB-65 ≥ 3 (OR = 5.206, OR = 7.921, OR = 3.974, OR = 18.002, respectively).
COPD patients hospitalized with CAP had higher rate of need for NIMV, need for ICU admission and severity scores than those without COPD. Aspiration, D-dimer > 2.0 μg/mL, comorbid with coronary heart disease, need for NIMV and CURB-65 ≥ 3 were mortality risk factors in CAP patients comorbid with COPD.
Patients with community acquired pneumonia (CAP) caused by viruses can develop severe complications, which result in hospitalization and death. The purpose of this study was to analyse the aetiology, ...incidence, clinical characteristics, and outcomes of CAP patients with fever during non-pandemics, and then to provide theoretical basis for accurate diagnosis and treatment in CAP patients.
An enrolment system was established for monitoring the CAP patients with fever. Multiplex polymerase chain reaction (mPCR) kits were used to detect 10 viruses influenza A and B, adenovirus (ADV), respiratory syncytial virus (RSV) A and B, picornavirus, parainfluenza virus (PIV), coronavirus, human metapneumovirus (HMPV), and bocavirus. Data on age, gender, underlying diseases, complications, laboratory indexes, and outcomes were collected by physicians.
This prospective study included 320 patients with fever. Among them, 23.4% were viral-positive by mPCR, with influenza virus most prominent followed by picornavirus. Strong variation in seasonal distribution was shown in viral infections, with peak months from December to February. Patients with influenza infection were likely to be taken to emergency rooms and have respiratory failure with higher creatinine kinase levels and lower white blood cell counts. Streptococcus pneumoniae followed by haemophilus influenzae were the most common bacteria in viral co-infections, which accounted for one third of virus-positive patients. Viral CAP and mixed CAP were not independent factors for death. In addition, lactate dehydrogenase (LDH) >246 IU/L odds ratio (OR) =7.06, 95% confidence interval (CI): 2.15-23.2, P=0.001, and serum calcium <2.18 mmol/L (OR =6.67, 95% CI: 1.42-31.3, P=0.016) were associated with death.
Viruses play an important role in CAP patients with fever, a systematic clinical, radiological and biological analysis of these patients can contribute to effective therapy that may prevent the development of CAP and improve the outcomes. The present work showed an elaborate analysis evidence of viral infection among fever CAP inpatients.
Pseudomonas aeruginosa (PA) has emerged as a pressing challenge to pulmonary infection and lung damage. The LL37 peptide is an efficient antimicrobial agent against PA strains, but its application is ...limited because of fast clearance in vivo, biosafety concerns, and low bioavailability. Thus, an albumin-based nanodrug delivery system with reduction sensitivity was developed by forming intermolecular disulfide bonds to increase in vivo LL37 performance against PA. Cationic LL37 can be efficiently encapsulated via electrostatic interactions to exert improved antimicrobial effects. The LL37 peptide exhibits greater than 48 h of sustained released from LL37 peptide nanoparticles (LL37 PNP), and prolonged antimicrobial effects were noted as the incubation time increased. Levels of inflammatory cytokines secreted by peritoneal macrophages, including TNF-α and IL-6, were reduced significantly after LL37 PNP treatment following PA stimulation, indicating that LL37 PNP inhibits PA growth and exerts anti-inflammatory effects in vitro. In a murine model of acute PA lung infection, LL37 PNP significantly reduced TNF-α and IL-1β expression and alleviated lung damage. The accelerated clearance of PA indicates that LL37 PNP could improve PA lung infection and the subsequent inflammation response more efficiently compared with free LL37 peptide. In conclusion, this excellent biocompatible LL37 delivery strategy may serve as an alternative approach for the application of new types of clinical treatment in future.
Neurotrauma has been recognized as a risk factor for neurodegenerative diseases, and sex difference of the incidence and outcome of neurodegenerative diseases has long been recognized. Past studies ...suggest that microglia could play a versatile role in both health and disease. So far, the microglial mechanisms underlying neurodegeneration and potentially lead to sex‐specific therapies are still very open. Here we applied whole transcriptome analysis of microglia acutely isolated at different timepoints after a cortical stab wound injury to gain insight into genes that might be dysregulated and transcriptionally different between males and females after cortical injury. We found that microglia displayed distinct temporal and sexual molecular signatures of transcriptome after cortical injury. Hypotheses and gene candidates that we presented in the present study could be worthy to be examined to explore the roles of microglia in neurotrauma and in sex‐biased neurodegenerative diseases.
Main Points
Microglia display distinct temporal and sexual molecular signatures of transcriptome after cortical injury.
Hypotheses and gene candidates are presented to explore the roles of microglia in neurotrauma and in sex‐biased neurodegenerative diseases.
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To investigate the expression of the precursor of brain-derived neurotrophic factor (proBDNF) and its high-affinity receptor p75NTR in neurons of emotion-related brain areas ...(prefrontal cortex, hippocampus, and amygdala) in rats with post-stroke depression (PSD), and to explore the expression levels of proBDNF and p75NTR in neurons of emotion-related brain areas by injecting tissue plasminogen activator (t-PA) into the lateral ventricle of PSD rats, this significantly improved the stress-induced depression-like behavior,thus further validating the above results.
Rats were randomly divided into four groups: a normal control group (n = 8), a depression group (n = 8), a stroke group (n = 8), and a PSD group (n = 8). The rat model of stroke was established by thread embolism, and the PSD animal model was induced by chronic unpredictable mild stress (CUMS) and solitary feeding. Behavioral tests were conducted, including weight measurement, open field tests, and sucrose preference tests. Immunofluorescence double labeling was used to detect the expression of proBDNF and p75NTR in neurons of emotion-related brain regions in the PSD rat model. Four weeks after CUMS treatment, the PSD group was selected. Rats were infused with t-PA (3 μg dissolved in 6 μL saline, Boehringer Ingelheim), proBDNF (3 μg dissolved in 6 μL saline, Abcam), or equal-volume NS once per day for 7 consecutive days using the syringe pump connecting to injection needles. After 7 days of continuous administration, animal behavior was assessed through scoring, and the expression of proBDNF and p75NTR in the emotion-related brain regions of the PSD rat model was detected using immunofluorescence double labeling.
Compared with the normal control group and the stroke group, the body weight, sucrose water consumption, and vertical movement distance in the PSD group were significantly lower (P < 0.05). In contrast, when compared with the proBDNF injection group and saline injection group, the weight, sucrose water consumption, field horizontal movement, and vertical movement distance of the t-PA injection group significantly increased after PSD lateral ventricle intubation.Double immunofluorescence revealed a higher neuronal expression of proBDNF as well as p75NTR in the prefrontal cortex and hippocampus of PSD rats compared to control animals (P < 0.05). In the amygdala, the expression levels of proBDNF and P75NTR were significantly reduced in the PSD group compared to the control group (P < 0.05). The results of the expression levels of proBDNF and P75NTR in the emotion-related brain regions of PSD rats injected with t-PA showed that proBDNF and P75NTR was significantly reduced in the prefrontal cortex, hippocampus, and amygdala of PSD rats compared to those of the NS and proBDNF groups (P < 0.05).
The increased expression of the brain-derived neurotrophic factor precursor proBDNF and its receptor p75NTR in neurons of emotion-related brain regions may play an important role in the pathogenesis of PSD.t-PA reduced the expression of proBDNF and its receptor p75NTR in neurons emotion-related brain regions and significantly improved the stress-induced depression-like behavior. Therefore, it is reasonable to assume that exogenous injection of t-PA may alleviate the depressive symptoms of PSD patients.Reducing the expression of proBDNF by injecting t-PA may provide a novel therapeutic approach for the treatment of stress-related mood disorders.
In recent years, obesity has become a key factor affecting human health.
Lam. is a perennial tropical deciduous tree, which is widely used in human medicine due to its nutritional and unique ...medicinal value. It has a cholesterol-lowering effect, but its mechanism of action is unclear. In this study, we elucidated the inhibitory effect of
leaf petroleum ether extract (MOPEE) on lipid accumulation by
and
experiments, and we described its mechanism of action. MOPEE suppressed adipogenesis in 3T3-L1 adipocytes in a dose-dependent manner and had no effect on cell viability at doses up to 400 μg/ml. Furthermore, MOPEE (400 μg/ml) significantly downregulated the expression of adipogenesis-associated proteins peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer-binding proteins α and β (C/EBPα and C/EBPβ), and fatty acid synthase (FAS) and upregulated the expression of a lipolysis-associated protein hormone-sensitive lipase (HSL) in 3T3-L1 adipocytes. Additionally, MOPEE (400 μg/ml) significantly increased the degree of phosphorylation of AMP-activated protein kinase α (AMPKα) and acetyl-CoA carboxylase (ACC). An AMPK inhibitor reversed the MOPEE-induced activation of AMPKα and ACC in 3T3-L1 adipocytes. Animal experiments showed that, in high-fat diet (HFD) mice, MOPEE 0.5 g/kg body weight (BW) effectively decreased BW; relative epididymal, perirenal, and mesenteric fat weight and fat tissue size; and hepatic fat accumulation. Furthermore, MOPEE markedly reduced the serum levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and aspartate aminotransferase (AST). Moreover, MOPEE significantly downregulated the expression of adipogenesis-associated proteins (PPARγ and FAS) and upregulated the expression of a lipolysis-associated protein adipose triglyceride lipase (ATGL) in HFD mice hepatic and epididymal fat tissue. Additionally, MOPEE markedly increased the degree of phosphorylation of AMPKα and ACC in HFD mice hepatic and epididymal fat tissue. Following ultrahigh-performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS/MS) analysis, three phytocompounds (isoquercitrin, chrysin-7-glucoside, and quercitrin) were identified as compounds with relatively high levels in MOPEE. Among them, quercitrin showed excellent fat accumulation inhibitory activity, and the three compounds had synergistic effects in inhibiting adipogenesis. Taken together, MOPEE inhibits fat accumulation by inhibiting the adipogenesis and promoting the lipolysis, and this process is related to AMPK activation.
Farnesyl diphosphate synthase(FPPS) is a key enzyme at the branch point of the sesquiterpene biosynthetic pathway, but there are no reports on the transcriptional regulation of FPPS promoter in ...Pogostemon cabin. In the early stage of this study, we obtained the binding protein PcFBA-1 of FPPS gene promoter in P. cabin. In order to explore the possible mechanism of PcFBA-1 involved in the regulation of patchouli alcohol biosynthesis, this study performed PCR-based cloning and sequencing analysis of PcFBA-1, analyzed the expression patterns of PcFBA-1 in different tissues by fluorescence quantitative PCR and its subcellular localization using the protoplast transformation system, detected the binding of PcFBA-1 protein to the FPPS promoter in vitro with the yeast one-hybrid system, and verified its transcriptional regulatory function by dual-luciferase reporter gene assay. The findings demonstrated that the cloned PcFBA-1 had an open reading frame(ORF) of 1 131 bp, encoding a protein of 376 amino acids, contain