Acetylshikonin induces autophagy-dependent apoptosis through the key LKB1-AMPK and PI3K/Akt-regulated mTOR signalling pathways in HL-60 cells.

Acetylshikonin (ASK) is a natural naphthoquinone derivative of traditional Chinese medicine Lithospermum erythrorhyzon. It has been reported that ASK has bactericidal, anti-inflammatory and antitumour effects. However, whether ASK induces apoptosis and autophagy in acute myeloid leukaemia (AML) cells and the underlying mechanism are still unclear. Here, we explored the roles of apoptosis and autophagy in ASK-induced cell death and the potential molecular mechanisms in human AML HL-60 cells. The results demonstrated that ASK remarkably inhibited the cell proliferation, viability and induced apoptosis in HL-60 cells through the mitochondrial pathway, and ASK promoted cell cycle arrest in the S-phase. In addition, the increased formation of autophagosomes, the turnover from light chain 3B (LC3B) I to LC3B II and decrease of P62 suggested the induction of autophagy by ASK. Furthermore, ASK significantly decreased PI3K, phospho-Akt and p-p70S6K expression, while enhanced phospho-AMP-activated protein kinase (AMPK) and phospho-liver kinase B1(LKB1) expression. The suppression of ASK-induced the conversion from LC3B I to LC3B II caused by the application of inhibitors of AMPK (compound C) demonstrated that ASK-induced autophagy depends on the LKB1/AMPK pathway. These data suggested that the autophagy induced by ASK were dependent on the activation of LKB1/AMPK signalling and suppression of PI3K/Akt/mTOR pathways. The cleavage of the apoptosis-related markers caspase-3 and caspase-9 and the activity of caspase-3 induced by ASK were markedly reduced by inhibitor of AMPK (compound C), an autophagy inhibitor 3-methyladenine (3-MA) and another autophagy inhibitor chloroquine (CQ). Taken together, our data reveal that ASK-induced HL-60 cell apoptosis is dependent on the activation of autophagy via the LKB1/AMPK and PI3K/Akt-regulated mTOR signalling pathways.

Transcriptional regulation and small compound targeting of ACE2 in lung epithelial cells.

Angiotensin-converting enzyme 2 (ACE2) is the receptor of COVID-19 pathogen SARS-CoV-2, but the transcription factors (TFs) that regulate the expression of the gene encoding ACE2 (ACE2) have not been systematically dissected. In this study we evaluated TFs that control ACE2 expression, and screened for small molecule compounds that could modulate ACE2 expression to block SARS-CoV-2 from entry into lung epithelial cells. By searching the online datasets we found that 24 TFs might be ACE2 regulators with signal transducer and activator of transcription 3 (Stat3) as the most significant one. In human normal lung tissues, the expression of ACE2 was positively correlated with phosphorylated Stat3 (p-Stat3). We demonstrated that Stat3 bound ACE2 promoter, and controlled its expression in 16HBE cells stimulated with interleukin 6 (IL-6). To screen for medicinal compounds that could modulate ACE2 expression, we conducted luciferase assay using HLF cells transfected with ACE2 promoter-luciferase constructs. Among the 64 compounds tested, 6-O-angeloylplenolin (6-OAP), a sesquiterpene lactone in Chinese medicinal herb Centipeda minima (CM), represented the most potent ACE2 repressor. 6-OAP (2.5 µM) inhibited the interaction between Stat3 protein and ACE2 promoter, thus suppressed ACE2 transcription. 6-OAP (1.25-5 µM) and its parental medicinal herb CM (0.125%-0.5%) dose-dependently downregulated ACE2 in 16HBE and Beas-2B cells; similar results were observed in the lung tissues of mice following administration of 6-OAP or CM for one month. In addition, 6-OAP/CM dose-dependently reduced IL-6 production and downregulated chemokines including CXCL13 and CX3CL1 in 16HBE cells. Moreover, we found that 6-OAP/CM inhibited the entry of SARS-CoV-2 S protein pseudovirus into target cells. These results suggest that 6-OAP/CM are ACE2 inhibitors that may potentially protect lung epithelial cells from SARS-CoV-2 infection.

Streptomyces taklimakanensis sp. nov., an actinomycete isolated from the Taklimakan desert.

A novel Streptomyces strain, designated TRM43335T, was isolated from the Taklimakan desert in Alar City, Xinjiang, north-west China. The strain was found to exhibit an inhibitory effect on biofilm formation by Candida albicans and Staphylococcus epidermidis. A polyphasic approach was used to determine its taxonomic status. The strain was observed to form abundant aerial mycelium, occasionally twisted and which differentiated into spiral spore chains. Spores of TRM43335T were observed to be oval-shaped, with a smooth surface. Strain TRM43335T was found to grow optimally at 37 °C, pH 8 and in the presence of 1% (w/v) NaCl. The major sugars were identified as ribose, xylose, glucose, mannose and galactose, and the principal phospholipids were found to be diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol mannoside and phosphatidylinositol. The diagnostic cell wall amino acid was identified as LL-diaminopimelic acid. The predominant menaquinone was found to be MK-9(H6). The major cellular fatty acids were identified as iso-C16:1 H, anteiso-C15:0, iso-C16:0, anteiso-C17:0, anteiso-C17:1 w9c and iso-C15:0. Analysis of the 16S rRNA sequence showed that strain TRM43335T exhibits high sequence similarity to Streptomyces desertarenae SYSU D8023T 98.69%. A multilocus sequence analysis of five house-keeping genes (atpD, gyrB, rpoB, recA and trpB) also illustrated that strain TRM43335T should be assigned to the genus Streptomyces. The DNA G + C content of the strain was determined to be 72.8 mol%. The average nucleotide identity relatedness between strain TRM43335T and the phylogenetically related strain S. desertarenae SYSU D8023T was found to be 89.23%, and the in silico DNA-DNA hybridization value to be 36.70%. Therefore, it is concluded that strain TRM43335T represents a novel species of the genus Streptomyces, for which the name Streptomyces taklimakanensis sp. nov is proposed. The type strain is TRM43335T (CCTCC AA 2018052 T = KCTC 49254 T).

[TLR4/NF-kappaB p65 signaling pathway mediates protective effect of triptolide on endothelium in rats with endotoxemia].

The aim of this paper was to observe the effect of triptolide( TP) on cardiovascular function and its possible mechanism by intraperitoneal injection of bacterial lipopolysaccharide in rats with endotoxemia. Sixty male Sprague-Dawley rats were randomly divided intonormal group( NC group),endotoxemia model group( LPS group),TP low concentration intervention group( LPS + TP-L group,25 µg·kg~(-1)),TP middle concentration intervention group( LPS+TP-M group,50 µg·kg~(-1)),TP high concentration intervention group( LPS+TP-H group,100 µg·kg~(-1)) and polymyxin B group( LPS+PMX-B group,0. 2 mg·kg~(-1)). 10 mg·kg~(-1) LPS was injected intraperitoneally for 6 h to replicate the endotoxemia rat model. The rats in TP intervention groups were pre-treated 15 min before intraperitoneal injection of LPS. Rats in each group underwent total arterial intubation to measure hemodynamic parameters: heart rate( HR),left ventricular diastolic pressure( LVDP),the maximum rate of the increase/decrease of left ventricular pressure( ±dp/dtmax). The levels of BNP,CK-MB and c Tn-Ⅰ in serum and levels of TNF-α and IL-6 in plasma were detected by ELISA. The contents of p65 protein in myocardium and contents of p65,TLR4,i NOS and e NOS protein in thoracic aorta were detected by Western blot. As compared with NC group,the hemodynamic indexes in LPS group were significantly decreased; the contents of BNP,CK-MB and c Tn-Ⅰ in serum,TNF-α and IL-6 in plasma,p65 in myocardium,i NOS,e NOS,TLR4 and p65 in vascular tissues were significantly increased. As compared with LPS group,the hemodynamic indexes were significantly improved in LPS+TP-M group,LPS+TP-H group and LPS+PMX-B group; the contents of BNP,CK-MB and c Tn-Ⅰ in serum,TNF-α and IL-6 in plasma,p65 in myocardium,i NOS,e NOS,TLR4 and p65 in vascular tissues were significantly decreased in each treatment group. Triptolide has a protective effect on cardiovascular damage in a dose-dependent manner in endotoxemia rats,probably through TLR4/NF-κB p65 signaling pathway to improve endothelial function.

The Study of Immune Response in PBMC of CHB Patients treated with IFN-α and 3-TC in vitro.

BACKGROUND: The primary aim of this study is to measure the JAK-STAT signaling in HBV infected peripheral blood mononuclear cells (PBMCs) stimulated by IFN-α and 3-TC and explore the influence of HBV to the JAKSTAT signaling pathways. METHODS: PBMCs were separated from healthy volunteers and patients who had not received any treatment with chronic hepatitis B. PBMCs were divided into the control group, IFN-α stimulation group, Lamivudine stimulation group, and combined treatment group. The expression of molecules of JAK-STAT signal transduction pathway (STAT1, STAT2, IRF9) and the antiviral protein (MxA) were detected by RT-qPCR and Western blot method. RESULTS: The majority of IFN-α inducible genes were expressed. The molecules of JAK-STAT signal transduction pathway (STAT1, STAT2, IRF9) and the antiviral protein (MxA) were highly expressed in IFN-α stimulation group and the combined treatment group. Compared to healthy controls, the expression levels of molecules (STAT1, IRF9) and the antiviral protein (MxA) are significantly lower in the control group, IFN-α stimulation group, and the combined treatment group of the CHB patients. CONCLUSIONS: IFN-α could activate JAK-STAT signaling transduction pathway in PBMCs of HBV-infected patients and HBV might process the activity to antagonize the antiviral activity in HBV infected PBMCs.

Identification of Suitable Candidate Reference Genes for Gene Expression Analysis by RT-qPCR in Peripheral Blood Mononuclear Cells of CHB Patients.

BACKGROUND: Quantitative polymerase chain reaction (qPCR) analysis is a precise and effective method for the study of mRNA expression throughout the field of peripheral blood mononuclear cell (PBMC) research. However, the use of suitable reference genes for data normalization is critical to obtain meaningful and reproducible results. The present study aimed to identify the greatest reference genes for further research in PBMC of Chronic Hepatitis B (CHB) patients. METHODS: We assessed the expression stability of four commonly used reference genes (beta actin, beta-tubulin, 18S rRNA, GAPDH) in PBMC of CHB patients. Then we employed geNorm, BestKeeper, and Normfinder to evaluate the expression stability of these reference genes. RESULTS: All four genes displayed no significant differences between patient and control groups except beta actin and thus beta actin should not be used as a normalizing gene in a discussed experimental setup. GAPDH and beta-tubulin composed the best pair of reference genes for normalization purposes in future studies of gene expression in PBMC of CHB patients according to three algorithms. CONCLUSIONS: GAPDH and beta-tubulin were the best combination of two reference genes in this study for RT-qPCR analysis.

Inhibition of AMPK expression in skeletal muscle by systemic inflammation in COPD rats.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a disease characterized by airflow limitation and inflammation. Meanwhile, COPD also is associated with metabolic disorders, such as skeletal muscle weakness. Strikingly, activation of AMP-activated protein kinase (AMPK) exerts critical roles in energy metabolism. However, it remains unclear whether and how the expression levels of AMPK are affected in the COPD model rats which may lead to the dysfunction of the skeletal muscle in these rats. METHODS: Here we developed a rat model of COPD, and we investigated the morphological changes of peripheral skeletal muscle and measured the levels of tumor necrosis factor -α (TNF-α) and AMPK in skeletal muscle by using approaches that include immunohistochemistry and polymerase chain reaction (PCR). RESULTS: We found that the expression levels of both AMPK mRNA and protein in skeletal muscles were significantly reduced in the COPD model rats, in comparison to those from the control rats, the COPD model rats that received treatments with AICAR and resveratrol, whereas the expression levels of TNF-α were elevated in COPD rats. CONCLUSION: Such findings indicate that AMPK may serve as a target for therapeutic intervention in the treatment of muscle weakness in COPD patients.

Porcine circovirus type 2 in China: an update on and insights to its prevalence and control.

Currently, porcine circovirus type 2 (PCV2) is considered the major pathogen of porcine circovirus associated-diseases (PCVAD) that causes large economic losses for the swine industry in the world annually, including China. Since the first report of PCV2 in 1998, it has been drawing tremendous attention for the government, farming enterprises, farmers, and veterinary practitioners. Chinese researchers have conducted a number of molecular epidemiological work on PCV2 by molecular approaches in the past several years, which has resulted in the identification of novel PCV2 genotypes and PCV2-like agents as well as the description of new prevalence patterns. Since late 2009, commercial PCV2 vaccines, including the subunit vaccines and inactivated vaccines, have already been used in Chinese swine farms. The aim of this review is to update the insights into the prevalence and control of PCV2 in China, which would contribute to understanding the epidemiology, control measures and design of novel vaccines for PCV2.

Enhanced levels of interleukin-8 are associated with hepatitis B virus infection and resistance to interferon-alpha therapy.

The objective of this study was to analyze the expression levels of IL-8 in serum and liver tissues from patients with chronic hepatitis B (CHB) infection and to investigate whether IL-8 may antagonize interferon-alpha (IFN-α) antiviral activity against HBV. IL-8 expression in serum was determined by enzyme linked immunosorbent assay (ELISA), and fluorescence-based quantitative real-time PCR (RT-qPCR) was used to measure IL-8 mRNA in peripheral blood mononuclear cells (PBMCs) in patients with CHB. IL-8 protein expression was detected in liver biopsy tissues by immunohistochemistry. In addition, the differences in serum IL-8 and PBMCs mRNA levels were also observed in patients with different anti-viral responses to IFN-α. Compared to normal controls, serum IL-8 protein and mRNA levels were increased in CHB patients, IL-8 levels were positively correlated with the severity of liver inflammation/fibrosis. Moreover, serum IL-8 protein and mRNA levels were positively correlated with serum alanine aminotransferase (ALT) level and negatively correlated with serum prealbumin (PA) level. IL-8 expression was mainly located in portal area of liver tissues and was increased with the severity of liver inflammation and fibrosis stage. The expression serum and mRNA levels of IL-8 in the CHB patients with a complete response to IFN-α are significantly lower than that of the patients with non-response to IFN-α treatment. It is suggested that IL-8 might play important roles in the pathogenesis of CHB. Moreover, interferon resistance may be related to the up-regulation of IL-8 expression in the patients did not respond to IFN-α treatment.

Oncogenic functions and therapeutic potentials of targeted inhibition of SMARCAL1 in small cell lung cancer.

Small cell lung cancer (SCLC) is a recalcitrant cancer characterized by high frequency loss-of-function mutations in tumor suppressors with a lack of targeted therapy due to absence of high frequency gain-of-function abnormalities in oncogenes. SMARCAL1 is a member of the ATP-dependent chromatin remodeling protein SNF2 family that plays critical roles in DNA damage repair and genome stability maintenance. Here, we showed that SMARCAL1 was overexpressed in SCLC patient samples and was inversely associated with overall survival of the patients. SMARCAL1 was required for SCLC cell proliferation and genome integrity. Mass spectrometry revealed that PAR6B was a downstream SMARCAL1 signal molecule which rescued inhibitory effects caused by silencing of SMARCAL1. By screening of 36 FDA-approved clinically available agents related to DNA damage repair, we found that an aza-anthracenedione, pixantrone, was a potent SMARCAL1 inhibitor which suppressed the expression of SMARCAL1 and PAR6B at protein level. Pixantrone caused DNA damage and exhibited inhibitory effects on SCLC cells in vitro and in a patient-derived xenograft mouse model. These results indicated that SMARCAL1 functions as an oncogene in SCLC, and pixantrone as a SMARCAL1 inhibitor bears therapeutic potentials in this deadly disease.

Centipeda minima and 6-O-angeloylplenolin enhance the efficacy of immune checkpoint inhibitors in non-small cell lung cancer.

BACKGROUND: Chemotherapeutic agents including cisplatin, gemcitabine, and pemetrexed, significantly enhance the efficacy of immune checkpoint inhibitors (ICIs) in non-small cell lung cancer (NSCLC) by increasing PD-L1 expression and potentiating T cell cytotoxicity. However, the low response rate and adverse effects limit the application of chemotherapy/ICI combinations in patients. METHODS: We screened for medicinal herbs that could perturb PD-L1 expression and enhance T cell cytotoxicity in the presence of anti-PD-L1 antibody, and investigated the underlying mechanisms. RESULTS: We found that the aqueous extracts of Centipeda minima (CM) significantly enhanced the cancer cell-killing activity and granzyme B expression level of CD8+ T cells, in the presence of anti-PD-L1 antibody. Both CM and its active component 6-O-angeloylplenolin (6-OAP) upregulated PD-L1 expression by suppressing GSK-3ß-ß-TRCP-mediated ubiquitination and degradation. CM and 6-OAP significantly enhanced ICI-induced reduction of tumor burden and prolongation of overall survival of mice bearing NSCLC cells, accompanied by upregulation of PD-L1 and increase of CD8+ T cell infiltration. CM also exhibited anti-NSCLC activity in cells and in a patient-derived xenograft mouse model. CONCLUSIONS: These data demonstrated that the induced expression of PD-L1 and enhancement of CD8+ T cell cytotoxicity underlay the beneficial effects of 6-OAP-rich CM in NSCLCs, providing a clinically available and safe medicinal herb for combined use with ICIs to treat this deadly disease.

CIP2A induces PKM2 tetramer formation and oxidative phosphorylation in non-small cell lung cancer.

Tumor cells are usually considered defective in mitochondrial respiration, but human non-small cell lung cancer (NSCLC) tumor tissues are shown to have enhanced glucose oxidation relative to adjacent benign lung. Here, we reported that oncoprotein cancerous inhibitor of protein phosphatase 2A (CIP2A) inhibited glycolysis and promoted oxidative metabolism in NSCLC cells. CIP2A bound to pyruvate kinase M2 (PKM2) and induced the formation of PKM2 tetramer, with serine 287 as a novel phosphorylation site essential for PKM2 dimer-tetramer switching. CIP2A redirected PKM2 to mitochondrion, leading to upregulation of Bcl2 via phosphorylating Bcl2 at threonine 69. Clinically, CIP2A level in tumor tissues was positively correlated with the level of phosphorylated PKM2 S287. CIP2A-targeting compounds synergized with glycolysis inhibitor in suppressing cell proliferation in vitro and in vivo. These results indicated that CIP2A facilitates oxidative phosphorylation by promoting tetrameric PKM2 formation, and targeting CIP2A and glycolysis exhibits therapeutic potentials in NSCLC.

Methoprene influences reproduction and flight capacity in adults of the rice leaf roller, Cnaphalocrocis medinalis (Guenee) (Lepidoptera: Pyralidae).

Juvenile hormone (JH) influences many aspects of insect biology, including oogenesis-flight syndrome tradeoffs between migration and reproduction. Drawing on studies of many migratory insects, we posed the hypothesis that JH influences migratory capacity and oogenesis in the rice leaf roller, Cnaphalocrocis medinalis. We treated adults moths (days 1, 2 and 3 postemergence) with the JH analog (JHA), methoprene, and then recorded the influences of JHA treatments on reproduction. JHA treatment on day 1 postemergence, but not on the other days, shortened the preoviposition period, although JHA did not influence total fecundity, oviposition period, or longevity. We infer day 1 postemergence is the JH-sensitive stage to influence reproduction. Therefore, we treated moths on day 1 postemergence with JHA and recorded flight capacity, flight muscle mass, and triacylglycerol (TAG) accumulation. JHA treatments did not influence flight speed, but led to reductions in flight durations and flight distances. At day 3 posttreatment (PT), JHA-treated females flew shorter times and less distance than the controls; JHA-treated males, however, only flew shorter times than the controls. JHA treatments led to reductions in flight muscle mass in females at days 2-3 PT and reductions in TAG content in females at day 3 PT, but, these parameters were not influenced by JHA in males. These findings strongly support our hypothesis, from which we infer that JH is a major driver in C. medinalis oogenesis-flight syndrome tradeoffs. Our data also reveal a JH-sensitive stage in adulthood during which JH influences the oocyte-flight syndrome in C. medinalis.

Mutations and clinical significance of calcium voltage-gated channel subunit alpha 1E (CACNA1E) in non-small cell lung cancer.

CACNA1E is a gene encoding the ion-conducting α1 subunit of R-type voltage-dependent calcium channels, whose roles in tumorigenesis remain to be determined. We previously showed that CACNA1E was significantly mutated in patients with non-small cell lung cancer (NSCLC) who were long-term exposed to household air pollution, with a mutation rate of 19% (15 of 79 cases). Here we showed that CACNA1E was also mutated in 207 (12.8%) of the 1616 patients with NSCLC in The Cancer Genome Atlas (TCGA) datasets. At mRNA and protein levels, CACNA1E was elevated in tumor tissues compared to counterpart non-tumoral lung tissues in NSCLCs of the public datasets and our settings, and its expression level was inversely associated with clinical outcome of the patients. Overexpression of wild type (WT) or A275S or R249G mutant CACNA1E transcripts promoted NSCLC cell proliferation with activation of epidermal growth factor receptor (EGFR) signaling pathway, whereas knockdown of this gene exerted inhibitory effects on NSCLC cells in vitro and in vivo. CACNA1E increased current density and Ca2+ entrance, whereas calcium channel blockers inhibited NSCLC cell proliferation. These data indicate that CACNA1E is required for NSCLC cell proliferation, and blockade of this oncoprotein may have therapeutic potentials for this deadly disease.

Long Non-Coding RNA and mRNA Expression Analysis in Liver of Mice With Clonorchis sinensis Infection.

Clonorchiasis is recognized as an important zoonotic parasitic disease worldwide. However, the roles of host long non-coding RNAs (lncRNAs) and messenger RNAs (mRNAs) in the response to Clonorchis sinensis (C. sinensis) infection remain unknown. Here we compared the expression of lncRNAs and mRNAs in the liver tissue of mice infected with C. sinensis, in order to further understand the molecular mechanisms of clonorchiasis. A total of 388 lncRNAs and 1,172 mRNAs were found to be differentially expressed with absolute value of fold change (FC) ≥ 2.0 and p < 0.05 by microarray. Compared with controls, Gm6135 and 4930581F22Rik were the most over- and under-expressed lncRNAs; flavin-containing monooxygenase 3 (Fmo3) and deleted in malignant brain tumors 1 (Dmbt1) were the most over- and under-expressed mRNAs. Moreover, functional annotation showed that the significantly different mRNAs were related with "FOXO signaling pathway", "Wnt signaling pathway", and "AMPK signaling pathway". Remarkably, lncRNA Gm8801 were significantly correlated with mRNA glycerol-3-phosphate acyltransferase mitochondrial (Gpam), insulin receptor substrate 2 (Irs2), and tumor necrosis factor receptor superfamily member 19 (Tnfrsf19) in ceRNA networks. These results showed that the expression profiles of lncRNAs and mRNAs in the liver changed after C. sinensis infection. Our results provided valuable insights into the lncRNAs and mRNAs involved in clonorchiasis pathogenesis, which may be useful for future control strategies.

Blockade of advanced glycation end product formation attenuates bleomycin-induced pulmonary fibrosis in rats.

BACKGROUND: Advanced glycation end products (AGEs) have been proposed to be involved in pulmonary fibrosis, but its role in this process has not been fully understood. To investigate the role of AGE formation in pulmonary fibrosis, we used a bleomycin (BLM)-stimulated rat model treated with aminoguanidine (AG), a crosslink inhibitor of AGE formation. METHODS: Rats were intratracheally instilled with BLM (5 mg/kg) and orally administered with AG (40, 80, 120 mg/kg) once daily for two weeks. AGEs level in lung tissue was determined by ELISA and pulmonary fibrosis was evaluated by Ashcroft score and hydroxyproline assay. The expression of heat shock protein 47 (HSP47), a collagen specific molecular chaperone, was measured with RT-PCR and Western blot. Moreover, TGFbeta1 and its downstream Smad proteins were analyzed by Western blot. RESULTS: AGEs level in rat lungs, as well as lung hydroxyproline content and Ashcroft score, was significantly enhanced by BLM stimulation, which was abrogated by AG treatment. BLM significantly increased the expression of HSP47 mRNA and protein in lung tissues, and AG treatment markedly decreased BLM-induced HSP47 expression in a dose-dependent manner (p < 0.05). In addition, AG dose-dependently downregulated BLM-stimulated overexpressions of TGFbeta1, phosphorylated (p)-Smad2 and p-Smad3 protein in lung tissues. CONCLUSION: These findings suggest AGE formation may participate in the process of BLM-induced pulmonary fibrosis, and blockade of AGE formation by AG treatment attenuates BLM-induced pulmonary fibrosis in rats, which is implicated in inhibition of HSP47 expression and TGFbeta/Smads signaling.

Ghrelin inhibits interleukin-8 production induced by hydrogen peroxide in A549 cells via NF-kappaB pathway.

Ghrelin, a novel growth hormone-releasing peptide, can influence appetite and induce positive energy balances. Previous studies have reported that ghrelin ameliorated inflammatory responses of the heart, liver and pancreas. We examined whether ghrelin inhibits the proinflammatory cytokine interleukin-8 production induced by hydrogen peroxide (H2O2) in human lung epithelia cell line A549 and which mechanism is related with this effect of ghrelin. A549 cells were preincubated with vehicle or ghrelin (0.1 to 1000 ng/mL) in a concentration-dependent manner and then H2O2 (0 to 50 microM) was added. The interleukin-8 released by A549 in the medium was determined by ELISA, the mRNA expressions of interleukin-8 and ghrelin receptor were detected by RT-PCR. We also examined the phosphorylation of NF-kappaB/p65 protein and the degradation of inhibitory protein-kappaB (I-kappaB) in A549 by western blot analysis, the NF-kappaB DNA-binding activity by electrophoretic mobility shift assay, and then detected the generation of reactive oxygen species (ROS) in A549 by nitroblue tetrazolium reduction assay. Cells treated with H2O2 (50 microM) exhibited significantly higher interleukin-8 production and ghrelin receptor mRNA expression compared with cells treated with vehicle alone (P < 0.05). Ghrelin inhibited H2O2-induced interleukin-8 production by A549 at both mRNA and protein levels in a concentration-dependent manner (P < 0.05). Moreover, ghrelin attenuated H2O2-triggered NF-kappaB activation dependent on I-kappaB degradation dose-dependently in A549, but the intracellular ROS level after application of H2O2 was not affected by ghrelin (1000 ng/mL). Together, these results suggest that ghrelin inhibits H2O2-induced interleukin-8 production in A549 cells by targeting on NF-kappaB pathway, but not by directly scavenging intracellular ROS.

[Niche and interspecific association of major nekton in the sea area to the east of the Nanji Islands]. / 南麂列岛东侧海域主要游泳动物生态位及种间联结性.

According to the fishery resources investigation data in the east of the Nanji Islands during autumn in 2017 and spring in 2018, the inter-specific relationships and ecological relationships between major nekton were analyzed via the index of relative importance, niche breadth, cluster analysis, niche overlap, χ2-test, variance ratio test, association coefficient, percentage of co-occurrence, and point correlation coefficients. The results showed that there were 30 major nekton species in this area. The dominant species were Harpadon nehereus, Portunus trituberculatus, and Oratosquilla oratoria. The niche width of these dominant species was relatively wide. Based on the cluster analysis of niche breadth, the 30 major nekton species could be divided into three categories, wide niche breadth species, moderate niche breath species, and narrow niche breath species. The distribution range of niche overlap value was [0, 0.98], indicating that there were differences in the similarity of species to resource utilization and that the niche was differentiated and accompanied by inter-specific competition. The values of VR and W showed that there was a significant positive correlation among the major nekton species. The χ2-test results indicated significantly interspecific association for 76 species pair (χ2≥3.841), which was related to community stability and species coexistence. Results of association coefficient, percentage of co-occurrence and point correlation coefficients test suggested that the interspecific association was strong and tended to be positive.

[Effects of phosphodiesterase-4 inhibitor on the mucin secretion in airway stimulated with acrolein: experiment with rats].

OBJECTIVE: To examine the effects of YM976, a phosphodiesterase (PDE)4 inhibitor, on mucin hypersecretion of airway stimulated with acrolein. METHODS: Forty-eight SD rat were randomly divided into 6 equal groups. Twenty-four rats underwent gastric perfusion of YM976 0.5, 1.5, or 4.5 mgxkg(-1)xd(-1) (n=8 for each group) and then underwent aerosol inhalation of 3.0 ppm acrolein 6 hours per day for 12 days so as to establish rat models of airway mucus hypersecretion. Eight rats underwent aerosol inhalation of 3.0 ppm acrolein only for 12 days to establish rat models of airway mucus hypersecretion without any drug intervention (acrolein model group). Eight rats underwent gastric perfusion of 5% methylcellulose and then acrolein inhalation for 12 days (methylcellulose group), and another 8 rats underwent gastric perfusion of YM976 4.5 mg/kg once a day and then inhalation of normal saline for 12 days (YM976 control group). On the 13th day the rats were killed. Bronchoalveolar lavage fluid (BALF) was acquired for cell count, and ELISA was used to detect the levels of tumor necrosis factor (TNF)-alpha and cytokine-induced neutrophil chemoattractant (CINC)-1 in the BALF. The mucin level in the airway mucous membrane was detected by alcian blue(AB)/periodic acid-Schiff(PAS) method. Muc5ac protein was measured by immunohistochemical staining and Western-blotting, and Muc5ac mRNA was detected by RT-PCR. RESULTS: The percentages of positive AB/PAS staining of the acrolein model group and the 3 YM976 groups (0.5, 1.5, and 4.5 mgxkg(-1)xd(-1)) were 23.65+/-2.86, 22.63+/-2.12, 16.34+/-1.72, and 5.03+/-0.72 respectively. The integral optical density (IOD) levels of Muc5ac immunohistochemical staining of the methylcellulose group and the 3 YM976 groups were 0.54+/-0.05, 0.49+/-0.06, 0.32+/-0.04, and 0.22+/-0.04 respectively. The IOD of Muc5ac protein expression by Western-blotting of the methylcellulose group and the 3 YM976 groups were 1.177+/-0.190, 0.806+/-0.180, 0.303+/-0.061, and 0.134+/-0.035 respectively. The IOD of Muc5ac mRNA expression by RT-PCR of the methylcellulose group and the 3 YM976 groups were 0.246+/-0.021, 0.223+/-0.020, 0.161+/-0.012, and 0.097+/-0.011 respectively. The TNF-alpha and CINC-1 levels in the BALF of the methylcellulose group and the 3 YM976 groups were (96.77+/-2.31), (87.65+/-2.75), (73.56+/-2.62), and (52.23+/-2.79) microg/L respectively, and (145.75+/-4.43), (139.73+/-5.51), (95.34+/-5.13), and (65.74+/-5.62) microg/L respectively, all significantly higher than those of the normal control group [4.38+/-0.32, 0.12+/-0.02, 0.058+/-0.024, 0.061+/-0.006, (18.23+/-2.32) microg/L and (33.56+/-3.43) microg/L respectively, all P<0.05], but those of the YM976 1.5 mgxkg(-1)xd(-1) and 4.5 mgxkg(-1)xd(-1) groups being significantly lower than those of the methylcellulose group (both P<0.05). CONCLUSION: YM976 inhibits airway inflammatory response and airway mucin hypersecretion induced by acrolein.