Epidemiologic evidence suggests that PM2.5 exposure aggravates asthma, but the molecular mechanisms are not fully discovered.
Ovalbumin (OVA)-induced mice exposed to PM2.5 were constructed. ...Pathological staining and immunofluorescence were performed in in vivo study. Gene set enrichment analysis (GSEA) was performed to identify the pathway involved in asthma severity by using U-BIOPRED data (human bronchial biopsies) and RNA-seq data (Beas-2B cells treated with PM2.5). Lentiviruses transfection, Real-time qPCR, immunofluorescence staining and trans-epithelial electrical resistance (TEER) measurement were performed for mechanism exploration in vitro.
PM2.5 exposure aggravated airway inflammation and mucus secretion in OVA-induced mice. Based on transcriptome analysis of mild-to-severe asthma from human bronchial biopsies, gene set enrichment analysis (GSEA) showed that up-regulated reactive oxygen species (ROS) pathway gene set and down-regulated apical junction gene set correlated with asthma severity. Consistent with the analysis of mild-to-severe asthma, after PM2.5 exposure, the ROS pathway in Beas-2B cells was up-regulated with the down-regulation of apical junction. The expression levels of genes involved in the specific gene sets were validated by using qPCR. The mRNA levels of junction genes, ZO-1, E-cadherin and Occludin, were significantly decreased in cells exposed to PM2.5. Moreover, it confirmed that inhibition of ROS recovered the expression levels of E-cadherin, Occludin and ZO-1, and ameliorated inflammation and mucus secretion in airway in OVA-induced mice exposed to PM2.5. Meanwhile, ROS level was elevated by PM2.5. By checking trans-epithelial electrical resistance (TEER) value, we also found that epithelial barrier was damaged after PM2.5 exposure. Importantly, Stanniocalcin 2 (STC2) was identified as a key gene in regulation of epithelial barrier. It showed that STC2 expression was up-regulated by PM2.5, which was recovered by NAC as well. Over-expression of STC2 could decrease the expression levels of ZO-1, Occludin and E-cadherin. Contrarily, suppression of STC2 could increase the expression levels of ZO-1, Occludin and E-cadherin reduced by PM2.5.
By using transcriptome analysis, we revealed that STC2 played a key role in PM2.5 aggravated airway dysfunction through regulation of epithelial barrier in OVA-induced mice.
•Joint analysis is a trend to investigate the key features of diseases.•PM2.5 aggravated the symptoms in OVA-induced asthma model.•STC2 played a novel role in epithelial barrier function after PM2.5 exposure.
In order to comprehend the underlying mechanisms contributing to the development and exacerbation of asthma resulting from exposure to fine particulate matter (PM2.5), we established an asthmatic ...model in fat mass and obesity-associated gene knockdown mice subjected to PM2.5 exposure. Histological analyses using hematoxylin-eosin (HE) and Periodic Acid-Schiff (PAS) staining revealed that the down-regulation of the fat mass and obesity-associated gene (Fto) expression significantly ameliorated the pathophysiological alterations observed in asthmatic mice exposed to PM2.5. Furthermore, the down-regulation of Fto gene expression effectively attenuated damage to the airway epithelial barrier. Additionally, employing in vivo and in vitro models, we elucidated that PM2.5 modulated FTO expression by inducing oxidative stress. Asthmatic mice exposed to PM2.5 exhibited elevated Fto expression, which correlated with increased levels of reactive oxygen species. Similarly, when cells were exposed to PM2.5, FTO expression was up-regulated in a ROS-dependent manner. Notably, the administration of N-acetyl cysteine successfully reversed the PM2.5-induced elevation in FTO expression. Concurrently, we performed transcriptome-wide Methylated RNA immunoprecipitation Sequencing (MeRIP-seq) analysis subsequent to PM2.5 exposure. Through the implementation of Gene Set Enrichment Analysis and m6A-IP-qPCR, we successfully identified inhibitor of nuclear factor kappa B kinase subunit beta (IKBKB) as a target gene regulated by FTO. Interestingly, exposure to PM2.5 led to increased expression of IKBKB, while m6A modification on IKBKB mRNA was reduced. Furthermore, our investigation revealed that PM2.5 also regulated IKBKB through oxidative stress. Significantly, the down-regulation of IKBKB effectively mitigated epithelial barrier damage in cells exposed to PM2.5 by modulating nuclear factor-kappa B (NF-κB) signaling. Importantly, we discovered that decreased m6A modification on IKBKB mRNA facilitated by FTO enhanced its stability, consequently resulting in up-regulation of IKBKB expression. Collectively, our findings propose a novel role for FTO in the regulation of IKBKB through m6A-dependent mRNA stability in the context of PM2.5-induced oxidative stress. Therefore, it is conceivable that the utilization of antioxidants or inhibition of FTO could represent potential therapeutic strategies for the management of asthma exacerbated by PM2.5 exposure.
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•Down-regulation of Fto attenuated airway epithelial barrier damage in PM2.5 –exposed asthmatic mice.•PM2.5-induced FTO was regulated by oxidative stress.•IKBKB was identified as a target regulated by FTO.•The decreased m6A modification by FTO in IKBKB mRNA enhanced IKBKB mRNA stability.•Inhibition of FTO may be the potential therapeutic option for treating asthma exposed to PM2.5.
Alternative splicing (AS) is an important mechanism for controlling gene expression, which regulates multiple biological processes in higher organisms. Chinese indigenous Xiang pig has distinctive ...biological characteristics, such as small size, early sexual maturity, lower litter size and not very clear exhibition of estrous behaviors. To further understand how AS responds to estrous cycles in Xiang pig, the genome-wide analysis of AS events was performed by RNA-seq method in Xiang pig ovaries at diestrous and estrous. Using ASprofile program, we analyzed twelve basic AS events in Xiang pig ovaries and identified 68,775 AS events in 15,142 genes from diestrous ovaries and 69,493 AS events in 15,291 genes from the estrous ovaries with average 4.54 splicing events. 94.4–95.5% of expressed genes underwent alternative splicing in this tissues. The frequencies of AS events were similar to each other at diestrous and estrous. Transcription start site (TSS) was the predominant type of AS events, followed by transcription terminal site (TTS), and skipped exon (SKIP). The remaining type of AS events, e.g., intron retention (IR) and alternative exon ends (AE), showed the lower frequencies. Further comparison analysis of gene expression indicated that 4,433 genes had at least one splice variant differentially expressed during estrous, whereas only 2,382 of them were differentially expressed at gene level. Numerous genes involved in gonad development and hormone metabolism were differentially regulated through AS. Twelve genes with different types of alternatively splicing were validated by using RT-PCR method. The GO annotation and KEGG pathway analysis clearly revealed that a lot of DEGs (differentially expressed genes) and DSGs (differentially spliced genes) were involved in follicular development and ovarian steroid biosynthesis. A large number of DSGs, although not differentially expressed, were enriched in circadian rhythm and several signaling pathways. These pathways potentially regulated the female animal reproductive function in gene and/or AS level. Our results suggested that alternative splicing play an essential role in regulation of gene expression in female pigs during estrous. Numerous genes involved in gonad development, hormone metabolism, circadian rhythm were differentially regulated through alternative splicing.
•Most expressed genes underwent AS in pig ovarian tissues.•AS played an essential role in regulation of gene expression in female pig during estrous.
Three new compounds, monarubins A-C (
,
and
), together with ten known compounds, including four alkaloids (
-
), two isocoumarins (
and
) and four polyketides (
-
), were isolated from marine ...shellfish-associated fungus
BB5. The structures were determined on the basis of the 1D and 2D NMR, MS, UV and IR data. The absolute configurations of compounds
,
and
were determined by ECD calculations. The NMR data of compounds deoxyhydroxyaspergillic acid (
) and 2-hydroxy-6-(1-hydroxy-1-methylpropyl)-3-
-buthylpyrazine (
) were first reported. All of the isolated compounds were evaluated for their cytotoxic activities against human nasopharyngeal carcinoma cell lines CNE1, CNE2, SUNE1 and HONE1 and hepatocellular carcinoma cell lines QGY7701 and HepG2. Monarubin B (
) displayed potent cytotoxicities against the cancer cell lines HepG2 and QGY7701 with IC
values of 1.72 and 0.71 μΜ, respectively; lunatinin (
) showed moderate cytotoxic activities against the cancer cell lines HepG2, QGY7701 and SUNE1 with the IC
values of 9.60, 7.12 and 28.12 μΜ, respectively.
This study reports the identification of a novel bacterial type II l-asparaginase, abASNase2, from Aquabacterium sp. A7-Y. The enzyme contains 319 amino acids and shared 35% identity with Escherichia ...coli type II l-asparaginase (EcAII), a commercial enzyme trademarked Elspar® that is widely used for medical applications. abASNase2 had high specific activity (458.9U/mg) toward l-asparagine, very low activity toward l-glutamine and d-glutamine and no activity toward d-asparagine. The optimal enzymatic activity conditions for abASNase2 were found to be 50mM Tris-HCl buffer (pH 9.0) at 60°C. It was very stable in the pH range of 7.0–11.0 and exhibited up to 80% relative activity after 2h below 40°C. The Km and kcat of abASNase2 were 1.8×10−3M and 241.9s−1, respectively. In addition, abASNase2’s ability to remove acrylamide from fried potato strips was evaluated. Compared to untreated potato strips (acrylamide content: 0.823±0.0457mg/kg), 88.2% acrylamide was removed in the abASNase2-treated group (acrylamide content: 0.097±0.0157mg/kg). These results indicate that the novel l-asparaginase abASNase2 is a potential candidate for applications in the food processing industry.
Hepatocyte nuclear factor‐1alpha (HNF1α) is one of the key transcription factors of the HNF family, which plays a critical role in hepatocyte differentiation. Substantial evidence has suggested that ...down‐regulation of HNF1α may contribute to the development of hepatocellular carcinoma (HCC). Herein, human cancer cells and tumor‐associated fibroblasts (TAFs) were isolated from human HCC tissues, respectively. A recombinant adenovirus carrying the HNF1α gene (AdHNF1α) was constructed to determine its effect on HCC in vitro and in vivo. Our results demonstrated that HCC cells and HCC tissues revealed reduced expression of HNF1α. Forced reexpression of HNF1α significantly suppressed the proliferation of HCC cells and TAFs and inhibited the clonogenic growth of hepatoma cells in vitro. In parallel, HNF1α overexpression reestablished the expression of certain liver‐specific genes and microRNA 192 and 194 levels, with a resultant increase in p21 levels and induction of G2/M arrest. Additionally, AdHNF1α inhibited the expression of cluster of differentiation 133 and epithelial cell adhesion molecule and the signal pathways of the mammalian target of rapamycin and transforming growth factor beta/Smads. Furthermore, HNF1α abolished the tumorigenicity of hepatoma cells in vivo. Most interestingly, intratumoral injection of AdHNF1α significantly inhibited the growth of subcutaneous HCC xenografts in nude mice. Systemic delivery of AdHNF1α could eradicate the orthotopic liver HCC nodules in nonobese diabetic/severe combined immunodeficiency mice. Conclusion: These results suggest that the potent inhibitive effect of HNF1α on HCC is attained by inducing the differentiation of hepatoma cells into mature hepatocytes and G2/M arrest. HNF1α might represent a novel, promising therapeutic agent for human HCC treatment. Our findings also encourage the evaluation of differentiation therapy for tumors of organs other than liver using their corresponding differentiation‐determining transcription factor. (HEPATOLOGY 2011)
Prevalence of atopic dermatitis (AD) is increasing worldwide. Up to date, there has been no face-to-face nation-wide study in China. We aim to explore the prevalence of clinical diagnosed AD in ...children aged 1-7 ys in China. Twelve metropolises were chosen from different areas of China. In each region, we selected 4-10 kindergartens and 2-5 vaccination clinics randomly. A complete history-taking and skin examination were performed by dermatologists. The definite diagnosis of AD and the severity were determined by two or three dermatologists. All criteria concerned in UK diagnosis criteria, characteristic presentation of AD and atypical manifestations were recorded in detail. A total of 13998 children from 84 kindergartens and 40 vaccination clinics were included. The prevalence of AD was 12.94% by clinical diagnosis of dermatologists overall, with 74.6% of mild AD. Comparatively, prevalence of AD based on UK diagnostic criteria was 4.76%. This is the first face-to-face nation-wide study in Chinese children aged 1-7 ys, revealing that the prevalence of AD in children is closer to that of wealthier nations.
AIM： To investigate the value of interleukin-8 （IL-8）, a pro-inflammatory chemokine, in predicting the prognosis of pancreatic cancer. METHODS： Expression of IL-8 and its receptor CXCR1 was assessed ...by immunohistochemistry in pancreatic cancer and chronic pancreatitis samples. Enzyme-linked immunosorbent assay was used to detect the serum IL-8 levels in pancreatic cancer patients. Human pancreatic cancer tissues were heterotopically transplanted to the immune-deficiency mice to evaluate the effect of serum IL-8 on the tumorigenesis of the cancer samples.RESULTS： IL-8 and CXCR1 proteins were both overexpressed in pancreatic adenocarcinoma samples （55.6% and 65.4%, respectively） compared with the matched para-cancer tissues （25.9% and 12.3%, P 〈 0.01）, or chronic pancreatitis （0% and 25%, P 〈 0.05）. Serum IL-8 levels in pancreatic cancer patients （271.1 ± 187.7 ng/mL） were higher than in other digestive system tumors, such as gastric cancer （41.77 ± 9.11 ng/mL, P = 0.025）, colorectal carcinoma （78.72 ± 80.60 ng/mL, P = 0.032） and hepatocellular carcinoma （59.60 ± 19.80 ng/mL, P = 0.016）. In vivo tumorigenesis analysis further proved that tumor tissues from patients with higher serum IL-8 levels grew faster than those with lower IL-8 levels. CONCLUSION： IL-8 can be a fine serum marker for predicting the prognosis pancreatic cancer.
To compare the plasma components of frozen plasma (FP) and fresh frozen plasma (FFP).
Twenty samples of FP and 20 samples of FFP from Beijing Red Cross Blood Center were randomly selected. ...Immediately after plasma melting, 12 plasma components including coagulation factor, fibrinolytic system and anticoagulation protein were detected, including activated partial thromboplastin time (APTT), prothrombin time (PT), coagulation factor Ⅷ (FⅧ) activity, coagulation factor Ⅴ (FⅤ) activity, fibrinogen(FIB) level, ADAMTS-13 activity, von Willebrand factor(vWF) activity, D-dimer (D-dimer, DD), fibrin degradation products (FDP), antithrombin (AT), protein C (PC), and protein S (PS). All these coagulation components between the two types of plasma were compared and analyzed.
Compared with FFP, APTT in FP was significantly prolonged(t=3.428, P<0.01), and PT was also significantly prolonged(z=-2.140, P<0.05), and FⅧ activity was decreased (t=-3.372, P<0.01), but all in the reference range, and PS activity was decreased(t=-
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