Ecotoxicity and trophic transfer of metallic nanomaterials in aquatic ecosystems.

Metallic nanomaterials (MNMs) possess unique properties that have led to their widespread application in fields such as electronics and medicine. However, concerns about their interactions with environmental factors and potential toxicity to aquatic life have emerged. There is growing evidence suggesting MNMs can have detrimental effects on aquatic ecosystems, and are potential for bioaccumulation and biomagnification in the food chain, posing risks to higher trophic levels and potentially humans. While many studies have focused on the general ecotoxicity of MNMs, fewer have delved into their trophic transfer within aquatic food chains. This review highlights the ecotoxicological effects of MNMs on aquatic systems via waterborne exposure or dietary exposure, emphasizing their accumulation and transformation across the food web. Biomagnification factor (BMF), the ratio of the contaminant concentration in predator to that in prey, was used to evaluate the biomagnification due to the complex nature of aquatic food chains. However, most current studies have BMF values of less than 1 indicating no biomagnification. Factors influencing MNM toxicity in aquatic environments include nanomaterial properties, ion variations, light, dissolved oxygen, and pH. The multifaceted interactions of these variables with MNM toxicity remain to be fully elucidated. We conclude with recommendations for future research directions to mitigate the adverse effects of MNMs in aquatic ecosystems and advocate for a cautious approach to the production and application of MNMs.

Co-exposure of butyl benzyl phthalate and TiO2 nanomaterials (anatase) in Metaphire guillelmi: Gut health implications by transcriptomics.

During the COVID-19 pandemic, an abundance of plastic face masks has been consumed and disposed of in the environment. In addition, substantial amounts of plastic mulch film have been used in intensive agriculture with low recovery. Butyl benzyl phthalate (BBP) and TiO2 nanomaterials (nTiO2) are widely applied in plastic products, leading to the inevitable release of BBP and nTiO2 into the soil system. However, the impact of co-exposure of BBP and nTiO2 at low concentrations on earthworms remains understudied. In the present study, transcriptomics was applied to reveal the effects of individual BBP and nTiO2 exposures at a concentration of 1 mg kg-1, along with the combined exposure of BBP and nTiO2 (1 mg kg-1 BBP + 1 mg kg-1 nTiO2 (anatase)) on Metaphire guillelmi. The result showed that BBP and nTiO2 exposures have the potential to induce neurodegeneration through glutamate accumulation, tau protein, and oxidative stress in the endoplasmic reticulum and mitochondria, as well as metabolism dysfunction. The present study contributes to our understanding of the toxic mechanisms of emerging contaminants at environmentally relevant levels and prompts consideration of the management of BBP and nTiO2 within the soil ecosystems.

Butyl benzyl phthalate exposure impact on the gut health of Metaphire guillelmi.

Agricultural films are extensively utilized in high-intensity agriculture, with China's annual usage reaching 1.5 million tons. Unfortunately, the recovery rate is less than 60%, leading to an inevitable accumulation of plastic mulch in agricultural soils. This accumulation primarily introduces butyl benzyl phthalate (BBP) into soil ecosystems, whose specific effects remain largely unclear, thereby posing potential risks. The present study focuses on the exposure impact of BBP on earthworms, Metaphire guillelmi, a commonly found endogenic earthworm within real farmland, as it provides insight into the direct interaction between biota gut health and contaminants. Specifically, we studied the biomarkers related to oxidative stress, the digestive system, and neurotoxicity within the gut of Metaphire guillelmi, and the integrated biological response (IBR) index was utilized to track these markers at different timeframes after BBP exposures. Our findings indicate that BBP exposures lead to oxidative damage, digestive system inhibition, and neurotoxicity, with IBR indexes of 14.6 and 17.3 on the 14th and 28th days, respectively. Further, the underlying mechanisms at a molecular level through molecular docking were investigated. The results showed that the most unstable interaction was with the Na+K+-ATPase (binding energy: -2.25 kcal-1), while BBP displayed stable bonds with superoxide dismutase and 8-hydroxydeoxyguanosine via hydrogen bonds and hydrophobic interaction. These interactions resulted in changes in protein conformation and their normal physiological functions, offering new insights into the molecular mechanism underlying enzymatic activity changes. This study has significant implications for the prediction of toxicity, environmental risk assessment, and the establishment of regulations related to BBP.

Untargeted metabolomics reveals sour jujube kernel benefiting the nutritional value and flavor of Morchella esculenta.

Nucleosides, organic acids, and amino acids separated from Morchella esculenta are well known for their nutritional value and flavor. However, how to increase their content in a better way has been a challenge. In this study, the effect of adding jujube kernel on the active components of M. esculenta was investigated by untargeted metabolomics using UPLC-MS/MS. A total of 1,243 metabolites were identified, of which 262 metabolites (21.078%) were organic acids and derivatives, 245 metabolites (19.71%) were lipids and lipid-like molecules, and 26 metabolites (2.092%) were nucleosides, nucleotides, and analogues. Subsequently, differential metabolites between groups were screened by the orthogonal partial least squares-discriminant analysis model, which showed that 256 metabolites were identified as significantly different for the positive ion model and 149 for the negative ion model. Moreover, significant differential metabolites (VIP > 1, P < 0.05) in annotation of kyoto encyclopedia of genes and genomes pathway were investigated, which showed that ABC transporters were the most commonly observed transporters, followed by pyrimidine metabolism and purine metabolism. The results indicated that the main components of jujube kernel might be conducive to the accumulation of nucleoside organic acids and amino acid metabolites in M. esculenta. These results provide important information for the understanding of more suitable way for cultivation of M. esculenta.

Six Cell Cycle-related Genes Serve as Potential Prognostic Biomarkers and Correlated with Immune Infiltrates in Hepatocellular Carcinoma.

Background: Cell cycle-related genes (CDK1, CDK5, CDC20, CCNA2, CCNB1, and CCNB2) play important roles in the regulation of mitotic cell cycle in eukaryotes. However, the correlation between cell cycle-related genes and tumor-infiltrating and prognosis of hepatocellular carcinoma (HCC) needs further investigation. Methods: Two public websites, Tumor Immune Estimate Resource (TIMER) and Oncomine, were used to assess the expression levels of cycle-related genes. We also analyzed the protein expression levels of six cell cycle-related genes using the HPA database. In addition, Kaplan-Meier plotter and Gene Expression Profiling Interactive Analysis (GEPIA) database were used to investigate the impact of cell cycle-related gene expression levels on the clinical prognosis of HCC. The correlation between cell cycle-related genes and cancer immune infiltrates was analyzed through TIMER site. Subsequently, GEPIA and TIMER database were used to assess the correlation between the expression of six cell cycle-related genes and polygenic markers in monocytes and macrophages, respectively. The cell cycle-related genes were also analyzed to find the associated genes with the highest alteration frequency, by the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) approaches of Metascape and String database, respectively. Results: The expression levels of cell cycle-related genes were up-regulated in tumor tissues compared with normal tissues. Subsequently, the expression of high cell cycle-related genes was positively correlated with poor overall survival (OS) and progression-free survival (PFS) in HCC, for CDK1 (OS: HR = 2.15, P = 1.1E-05 PFS: HR = 2.03, P = 2.3E-06), CDK5 (OS: HR = 1.85, P = 0.0035 PFS: HR = 1.26, P = 0.17), CDC20 (OS: HR = 2.49, P = 5.1E-07 PFS: HR = 1.77, P = 0.00012), CCNA2 (OS: HR = 1.92, P = 0.00018 PFS: HR = 1.96, P = 5.2E-06), CCNB1 (OS: HR = 2.34, P = 3.4E-05 PFS: HR = 1.97, P = 5.3E-06), and CCNB2 (OS: HR = 1.91, P = 0.0013 PFS: HR = 1.63, P = 0.0011), respectively. Furthermore, the transcription level of cell cycle-related genes was significantly correlated with immune infiltrating levels of CD4+ T and CD8+ T cells, neutrophils, macrophages, and dendritic cells (DCs) in HCC, respectively. Amongst them, the expression levels of CDK1, CDC20, CCNA2, CCNB1 and CCNB2 manifest strongly correlated with diverse immune marker sets in HCC. Conclusions: Our results demonstrated that cell cycle-related genes played key roles in the prognosis of HCC. Meanwhile, they were significantly correlated with immune infiltrating levels of CD4+ T cells, CD8+ T cells, neutrophils, macrophages and DCs in HCC, respectively. In addition, CDK1, CDC20, CCNA2, CCNB1 and CCNB2 expressions may be involved in the regulation of monocytes and tumor-associated macrophages (TAMs) in HCC, respectively. These findings strongly suggested that cell cycle-related genes could be used as novel biomarkers for exploring the prognosis and immune cells infiltration of HCC.

Generation of Hepatocytes and Nonparenchymal Cell Codifferentiation System from Human-Induced Pluripotent Stem Cells.

To date, hepatocytes derived from human-induced pluripotent stem cells (hiPSC) provide a potentially unlimited resource for clinical application and drug development. However, most hiPSC-derived hepatocyte-like cells initiated differentiation from highly purified definitive endoderm, which are insufficient to accurately replicate the complex regulation of signals among multiple cells and tissues during liver organogenesis, thereby displaying an immature phenotypic and short survival time in vitro. Here, we described a protocol to achieve codifferentiation of endoderm-derived hepatocytes and mesoderm-derived nonparenchymal cells by the inclusion of BMP4 into hepatic differentiation medium, which has a beneficial effect on the hepatocyte maturation and lifespan in vitro. Our codifferentiation system suggests the important role of nonparenchymal cells in liver organogenesis. Hopefully, these hepatocytes described here provide a promising approach in the therapy of liver diseases.

Production and characterization of polyclonal and monoclonal antibodies of lamprey pore-forming protein.

In the most primitive jawless vertebrate lamprey, the complement-dependent cytotoxicity regulated by variable lymphocyte receptors (VLRs) plays an important role in the adaptive immunity. Our previous studies have shown that the lamprey pore-forming protein (LPFP) acted as the terminal effector of VLR to lyse and kill the target cells. Here, the recombinant GST-LPFP protein was expressed and purified in prokaryotic expression system, and then used as the immunogen to produce mouse monoclonal antibody and rabbit polyclonal antibody. With these antibodies, we proved that LPFP existed as homodimers in the lamprey serum, and could be recruited to the membrane of target cells after stimulation. In conclusion, the antibodies we produced could specifically recognize the LPFP protein, which could be the useful tools to further study the pore-forming mechanism of LPFP.

Production of Functional Hepatobiliary Organoids from Human Pluripotent Stem Cells.

The research on human hepatobiliary development and disorders has been constrained by minimal access to human fetal tissue, and low accuracy of animal models. To overcome this problem, we have established a system for the differentiation of human pluripotent stem cells (hPSCs) into functional hepatobiliary organoids (HBOs). We have previously reported that our 45-d approach closely mimics key stages of hepatobiliary development, starting with the differentiation of hiPSC into endoderm and a small part of mesoderm, and subsequently into hepatoblast-like cells, followed by the parallel generation of hepatocyte-like cells and cholangiocyte-like cells, formation of immature HBO expressing early hepatic and biliary markers, and mature HBO displaying hepatobiliary functionality. In this study, we present an updated version of our previous protocol, which only needs 35 days to achieve maturation in vitro. Furthermore, a hepatobiliary culture medium is developed to functionally maintain the HBOs for more than 1.5 months. The capacity of this approach for producing large amounts of functional HBOs and enabling long-term culture in vitro holds promise for applications on developmental research, disease modeling, as well as screening of therapeutic agents.

Association of hepatitis C infection and risk of kidney cancer: A systematic review and meta-analysis of observational studies.

Although some epidemiological studies have investigated the association between Hepatitis C virus (HCV) infection and the development of kidney cancer, the results are far from consistent. We conducted a systematic review and meta-analysis of observational studies to determine the association. PubMed, EMBASE and Cochrane database were searched from 1 January 1975 to 7 January 2020. Study selection, data extraction and bias assessment (using the Newcastle-Ottawa scale) were performed independently by 2 authors. Pooled odds ratios (ORs) with corresponding confidence intervals (CIs) were calculated using a random-effects model. In all, 16 studies (11 cohort studies and 5 case-control studies) involving a total of 391,071 HCV patients and 38,333,839 non-HCV controls were included. The overall analysis showed a 47% higher risk to develop kidney cancer among the patients with HCV infection (pooled OR 1.47; 95% CI 1.14-1.91), despite significant heterogeneity (I2  = 87.6%). The multivariable meta-regression showed that study design, age, sample size and HIV co-infection were significant sources of variance, and totally accounted for 82% of the I2 . The risk of KC in HCV patients was further increased in studies without HCV/HBV- and HCV/HIV- co-infection (pooled OR 1.66; 95%CI 1.23-2.24). Multiple sensitivity analyses did not change the significant association. The present meta-analysis indicated that HCV-infected patients have a significantly higher risk of developing kidney cancer. Our results highlighted the rationale for improved renal surveillance in HCV patients for the early diagnosis of kidney cancer. Further investigations for the mechanisms underlying HCV-induced kidney cancer are warranted.

Gene Mining and Sequence Analysis of Purine Nucleosidase Based on RNA-Seq.

Caterpillar fungus (Ophiocordyceps sinensis) is one of the most valued fungal Traditional Chinese medicine (TCM), and it contains plenty of active ingredients such as adenosine. Adenosine is considered as a biologically effective ingredient that has a variety of anti-tumor and immunomodulatory activities. In order to further elucidate the mechanism of purine nucleosidase (PN) in adenosine biosynthesis, a gene encoding PN was successfully mined and further analyzed based on the RNA-Seq database of caterpillar fungus. The full-length cDNA of PN was 855 bp, which encoded 284 amino acids. BLAST analysis showed the highest homology of 85.06% with nucleoside hydrolase in NCBI. ProtProm analysis showed that the relative molecular weight was 30.69 kDa and the isoelectric point was 11.55. The secondary structure of PN was predicted by Predict Protein; the results showed that alpha helix structure accounted for 28.17%, strand structure accounted for 11.97%, and loop structure accounted for 59.86%. Moreover, PN gene was further cloned from transcriptome and detected by agarose gel electrophoresis for verification. This study provides more sufficient scientific basis and new ideas for the genetic regulation of adenosine biosynthesis in fungal TCM.

Human Hepatic Cancer Stem Cells (HCSCs) Markers Correlated With Immune Infiltrates Reveal Prognostic Significance of Hepatocellular Carcinoma.

BACKGROUND: Several markers have been reported to be specific for hepatic cancer stem cells (HCSCs), which is usually thought to be highly associated with poor clinical outcomes. Tumor-infiltrating immune cells act as an important factor for oncogenesis. Little is known about the correlation of HCSC markers to prognosis and immune infiltrates. METHODS: Expression of HCSC markers was analyzed through Oncomine database, Gene Expression Profiling Interactive Analysis (GEPIA) and Integrative Molecular Database of Hepatocellular Carcinoma (HCCDB), respectively. The prognostic effect of HCSC markers was evaluated using Kaplan-Meier plotter in association with different tumor stages, risk factors, and gender. The correlation of HCSC markers to tumor-infiltrating immune cells was tested by Tumor Immune Estimation Resource (TIMER). HCSC markers related gene sets were investigated by GEPIA, with their biological functions being analyzed by Cytoscape software. RESULTS: The expression level of 10 HCSC markers in HCC was higher than that in normal tissues in at least one database. Among them, high expression of CD24, SOX9, and SOX12 was positively correlated with poor prognosis (CD24: OS P = 0.0012, PFS P = 7.9E-05. SOX9: OS P = 0.012. SOX12: OS P = 0.0004, PFS P = 0.0013, respectively). However, the expression of CD13, CD34 and ALDH1A1 was associated with prolonged OS and PFS. SOX12 was significantly upregulated in poor prognosis of HCC patients with different conditions. Besides, total nine HCSC markers were identified to be positively associated with immune infiltration, including SOX12. Furthermore, Toll-like receptor signaling pathway was found to be one major pathway of these HCSC markers related gene networks. CONCLUSION: Our results suggest that seven upregulated HCSC markers (CD90, EpCAM, CD133, CD24, SOX9, CK19, and SOX12) are related with poor prognosis and immune infiltration in HCC. In addition, we find that high SOX12 expression remarkably affect prognosis in male HCC patients but not in female. HCC patients under viral infection or alcohol intake with increased SOX12 expression had poorer prognosis. Therefore, HCSCs markers likely play an important role in tumor related immune infiltration and SOX12 might be a potential therapeutic target in patients with HCC.

Congenital Cystic Adenomatoid Malformation Volume Ratio in Prenatal Assessment of Prognosis of Fetal Pulmonary Sequestrations.

This study aimed to evaluate the prognosis of pulmonary sequestration (PS) by measuring congenital cystic adenomatoid malformation volume ratio (CVR) value in fetal congenital PS. The fetal CVR in 49 cases of fetal PS diagnosed by prenatal ultrasound in Xiangyang No. 1 People's Hospital from March 2010 to June 2017 were measured, and the clinical outcomes were observed. According to the prenatal ultrasound CVR value, 49 fetuses diagnosed with PS were divided into 2 groups: group 1 with CVR≥1.26, and group 2 with CVR<1.26. The incidence rate of fetal edema, respiratory distress symptoms and survival rate were compared between the two groups. The risk factors of the fetal PS were evaluated by single and multiple Logistic regression analysis. The correlation between CVR and fetal prognosis was analyzed. Of the 49 fetuses, there were 34 cases of PS (ILS) type (69.39%, 34/49), 10 cases of PS (ELS) type I (20.41%, 10/49) and 5 cases of PS (ELS) type II (10.20%, 5/49). Forty-six cases (93.88%, 46/49) were born alive, there was 1 case (CVR ≥1.26) (2.04%, 1/49) of induced abortion, and 2 cases (CVR ≥1.26) (4.08%, 2/49) of stillbirths. In group 1 (n=24), 21 cases were born alive, and the incidence rate of newborn respiratory distress and fetal edema was 100% (21/21) and 79.17% (19/24) respectively. In group 2 (n=25), there were 3 cases (12%,3/25) of newborn respiratory distress, 3 cases (12%, 3/25) of fetal edema, and the rate of live birth was 100%. There were statistically significant differences between the two groups in the incidence of fetal edema, postpartum respiratory symptoms and survival rate. CVR was a risk factor for PS and was associated with fetal prognosis. CVR in the midtrimester of pregnancy is an effective index to evaluate the prognosis of fetal PS. CVR ≥1.26 is associated with an increased risk of fetal edema, infant respiratory distress and intrauterine or postnatal death.

Development of a deep eutectic solvent-based matrix solid phase dispersion methodology for the determination of aflatoxins in crops.

A novel and sensitive deep eutectic solvent-based matrix solid phase dispersion (DES-MSPD) method for the determination of aflatoxins (AFB1, AFB2, AFG1, AFG2) in various crops was established using high-performance liquid chromatography with fluorescence detection (HPLC-FLD). The DES-MSPD sample preparation procedure was optimized. Based on the optimal conditions, the intra-day and inter-day variability for AFs in all crop samples was less than 7.5%. Linearity was observed with R2 values (>0.994). Using the present method, HPLC-FLD gave the limits of detection (LODs) of 0.03-0.10 µg/kg and the limits of quantification (LOQs) of 0.10-0.33 µg/kg for AFs. This work represents the first attempt of using DESs as a green extraction medium for the extraction of AFs in MSPD. Compared with conventional MSPD methods, the DES-MSPD procedure looks promising as a relatively simple and low cost process to build an assay that can be used for monitoring concentrations of AFs in crops.

Generation of hepatobiliary organoids from human induced pluripotent stem cells.

BACKGROUND & AIMS: Human induced pluripotent stem cell (hiPSC)-derived liver modeling systems have the potential to overcome the shortage of donors for clinical application and become a model for drug development. Although several strategies are available to generate hepatic micro-tissues, few have succeeded in generating a liver organoid with hepatobiliary structure from hiPSCs. METHODS: At differentiation stages I and II (day 1-15), 25% of mTeSR™ culture medium was added to hepatic differentiation medium to induce endodermal and mesodermal commitment and thereafter hepatic and biliary co-differentiation. At stage III (day 15-45), 10% cholesterol+ MIX was added to the maturation medium to promote the formation and maturation of the hepatobiliary organoids. Phenotypes and functions of organoids were determined by specific markers and multiple functional assays both in vitro and in vivo. RESULTS: In this system, hiPSCs were induced to form 3D hepatobiliary organoids and to some extent recapitulated key aspects of early hepatogenesis in a parallel fashion. The organoids displayed a series of functional attributes. Specifically, the induced hepatocyte-like cells could take up indocyanine green, accumulate lipid and glycogen, and displayed appropriate secretion ability (albumin and urea) and drug metabolic ability (CYP3A4 activity and inducibility); the biliary structures in the system showed gamma glutamyltransferase activity and the ability to efflux rhodamine and store bile acids. Furthermore, after transplantation into the immune-deficient mice, the organoids survived for more than 8 weeks. CONCLUSION: This is the first time that functional hepatobiliary organoids have been generated from hiPSCs. The organoid model will be useful for in vitro studies of the molecular mechanisms of liver development and has important potential in the therapy of liver diseases. LAY SUMMARY: Herein, we established a system to generate human induced pluripotent stem cell-derived functional hepatobiliary organoids in vitro, without any exogenous cells or genetic manipulation. To some extent this model was able to recapitulate several key aspects of hepatobiliary organogenesis in a parallel fashion, holding great promise for drug development and liver transplantation.

RASgrf1, a Potential Methylatic Mediator of Anti-epileptogenesis?

Epileptogenesis, induced by status epilepticus (SE), is a chronic process, and intervention in this progress may prevent chronic epilepsy. It has been proposed that DNA methylation might be related with epileptogenesis. RASgrf1 has a differentially methylated region at the promoter which can silence gene expression. We have previously observed the down-regulation of RASgrf1 in epilepsy patients and proved that hypermethylation of RASgrf1 reaches maximal level at the latent period in mice after kainate-induced SE (KA mice), with corresponding alteration of RASgrf1 expression. In the present study, N-phthalyl-L-tryptophan (RG108), a DNA methyltransferase inhibitor, was applied in KA mice at latent phase and the behavior, electroencephalogram and pathological changes were observed in chronic phase. Methylation and expression of RASgrf1 were determined by polymerase chain reaction (PCR), western blotting, and bisulfite sequencing PCR. The results showed that the incidence of spontaneous recurrent seizures (SRS) was significantly lower in the RG108 group than the normal saline (NS) group. Subgroup analysis showed significant hypermethylation and lower expression of RASgrf1 in the RG108-SRS subgroup and the NS-SRS subgroup but not in the RG108-NSRS (no SRS) subgroup and the NS-NSRS subgroup compared with the control group. No significant difference was found between the RG108-SRS and NS-SRS subgroups. Meanwhile, hippocampal neuronal loss was observed in RG108-SRS and NS-SRS subgroups. We thus demonstrated that RG108 could modify the progression of epileptogenesis after KA induced SE and prevent chronic epilepsy. Meanwhile, hypermethylation of RASgrf1 after KA induced SE could be reversed with corresponding changes of RASgrf1 expression. Additionally, we speculated that RASgrf1 might be a potential epigenetic mediator in epileptogenesis and chronic epilepsy.

Association of RASgrf1 methylation with epileptic seizures.

DNA methylation, one of the mechanisms of epigenetic regulation, has been suggested to be related with epilepsy. RASgrf1 is a paternally imprinted gene and has a differentially methylated region (DMR) at the promoter that can silence gene expression. We have previously observed the down-regulation of RASgrf1 in the temporal neocortex of epilepsy patients and in the hippocampus of epileptic animals. Here, we further explored the dynamic change (1-day acute period, 10-day latent period and 45-day chronic phase) of DNA methylation and RASgrf1 expression after acute epileptic seizures in kainic acid (KA)-treated mice, and we observed the impact of N-phthalyl-L-tryptophan (RG108), a DNA methyltransferase (DNMT) inhibitor, on an acute epileptic model by polymerase chain reaction (PCR), western blotting, and bisulfite sequencing PCR (BSP). The results directly showed that the methylation of the RASgrf1 promoter gradually increased and reached a maximal level at the latent period, with subsequent suppression of RASgrf1 mRNA and protein expression levels, which reached a minimum level in the chronic phase. RG108 inhibited the increased methylation of the RASgrf1 gene, with significant inhibition occurring at the latent period, and restored RASgrf1 expression levels in the chronic phase. In addition, we demonstrated that RG108 could suppress acute epileptic seizures in KA-treated mice and epileptic discharges in 4-aminopyridine (4-AP)-treated hippocampal slices. These findings demonstrate that RASgrf1 is closely associated with epilepsy via the aberrant methylation of RASgrf1, and regulating the methylation status of relevant genes might be an intriguing topic in future research on epilepsy.

Fas-associated factor 1 inhibits tumor growth by suppressing Helicobacter pylori-induced activation of NF-κB signaling in human gastric carcinoma.

Loss of Fas-associated factor 1 (FAF1) may act as a pro-survival signal in diseased cells, but whether this is true in gastric carcinoma remains unclear. Here we report that FAF1 was expressed at low levels in gastric carcinoma tissues and cell lines, and its expression correlated with larger tumors, higher histology grade, higher TNM stage, tumor infiltration, and lymph node metastasis. Univariate analysis and survival curve analysis identified low FAF1 expression as a predictor of poor prognosis. FAF1 overexpression in HGC-27 gastric cancer cells induced cell apoptosis and inhibited cell proliferation and growth. It also reduced colony formation in vitro and tumor growth in mice. We found that Helicobacter pylori, a risk factor for gastric cancer, down-regulated FAF1 expression via NF-κB signaling. Knock-down of IKKß or p65 expression in gastric cancer cells reversed H. pylori-induced down-regulation of FAF1 expression and partially blocked H. pylori-induced secretion of inflammatory cytokines TNF-α and IL-8. Our results suggest that loss of FAF1 contributes to human gastric carcinogenesis by allowing H. pylori to activate NF-κB signaling.

Identification of pathways related to FAF1/H. pylori-associated gastric carcinogenesis through an integrated approach based on iTRAQ quantification and literature review.

Previously we showed that down-regulation of tumor suppressor FAF1 mRNA, potentially caused by H. pylori, correlated with increasing tumor differentiation and distant metastasis in gastric cancer. To identify molecular details about how FAF1 and H. pylori contribute to gastric carcinogenesis, we used the iTRAQ labeling approach involving LC-MS/MS to perform proteomic analysis of HGC-27 gastric cancer cells stably transfected with an FAF1 transgene and/or infected with H. pylori. Of the 2926 proteins examined, proteomics identified 157 for which the expression was altered as a result of FAF1 expression, 500 with altered expression as a result of H. pylori infection, and 246 with altered expression as a combined result of FAF1 expression and H. pylori infection. A literature review identified 21 proteins as being differentially expressed in H. pylori-associated gastric cancer in at least two studies. These two complementary analyses were combined in Ingenuity Pathway software, which predicted that FAF1/H. pylori-associated gastric carcinogenesis alters primarily biochemical pathways related to mitochondrial dysfunction, oxidative phosphorylation, integrin signaling, cholesterol/leucine metabolism and G2/M checkpoint regulation. Differential expression of key proteins in several of these pathways was validated by immunoblotting in HGC-27 cells. This integrated approach combining proteomics and literature searching may prove fruitful for elucidating how FAF1 expression and H. pylori infection affect gastric carcinogenesis. BIOLOGICAL SIGNIFICANCE: We established, for the first time, the proteomics databases of gastric cancer cell HGC-27 overexpressing FAF1 and infected with H. pylori through an integrated approach based on iTRAQ quantification and literature review, this strategy responded to the call for greater focus on data integration in primary/previous proteomic studies; and provided an integrated picture of the reference pathways and networks behind FAF1/H. pylori-associated gastric carcinogenesis, particularly pathways of mitochondrial dysfunction, oxidative phosphorylation, integrin signaling, cholesterol/leucine metabolism and G2/M checkpoint regulation.

Upregulated dynamin 1 in an acute seizure model and in epileptic patients.

Dynamin 1 is a neuron-specific guanosine triphosphatase (GTPase) that is an essential component of membrane fission during synaptic vesicle recycling and endocytosis. This study evaluated the dynamin 1 expression pattern in the acute lithium-pilocarpine rat model and in patients with temporal lobe epilepsy (TLE) and investigated whether altering the dynamin 1 expression pattern affects epileptic seizures in vivo and in vitro. The immunofluorescence, western blot analysis, and reverse transcription-PCR results show that the dynamin 1 expression level increased significantly in experimental rats from day 1 to day 7 after the onset of seizures and was significantly higher in TLE patients. The behavioral study revealed that inhibiting dynamin 1 increased the latency time of the first seizure and decreased the frequency and severity of the seizures. In addition, electrophysiological recordings from brain slices showed that inhibiting dynamin 1 reduces the frequency of Mg-free induced seizure-like activity. The anticonvulsant effect of dynasore was more effective at 10 µM than at 1 µM or 160 µM. These results indicate that the altered level of dynamin 1 may contribute to the development of epileptic seizures and that the targeted regulation of dynamin 1 activity may control epileptic seizures.

Intermedin inhibits uptake of oxidized LDL via CD36 pathway in RAW264.7 cells.

Intermedin (IMD) exerts a potent function in preventing atherosclerosis, while the mechanism remains unclear. Here we investigated the potential molecular mechanism responsible for the protective function of IMD in preventing foam cell formation in RAW264.7 cells. In our present study, IMD significantly inhibited intracellular cholesterol accumulation. Additionally, IMD dose-dependently down-regulated CD36 expression, which was confirmed by real-time quantitative reverse transcription-PCR and Western blot analysis. Our data suggest that IMD could inhibit the formation of foam cells through, at least partly, a CD36-dependent mechanism. This study suggests that IMD may be a therapeutic candidate for treating atherosclerosis.