Search

Background Trichothecenes are the most common toxins found in grains and mainly produced by Fusarium graminearum species complex (FGSC). However, a population of FGSC strain was found to produce a group of type A trichothecenes, NX toxins. Studies on this toxigenic Fusarium population and the emerging NX toxins are crucial for grain production and food safety. Scope and approach In this review, we systematically introduced the diagnostic techniques, population distribution and frequency of the NX-producing strains. The structure elucidation, stability, and toxicology of NX toxins were summarized. The molecular mechanisms of NX toxins biosynthesis were discussed. Key findings and conclusions The available information showed that NX-producing strains endemic to the border of Canada and United States, and TRI1 gene is the key determinant of NX production in FGSC. Structure elucidation results showed that NX toxins are similar in structure to type B trichothecenes but lack the keto group at C-8. In vitro experiments indicated that NX toxins can inhibit the eukaryotic protein synthesis and comparable toxic effects of NX-3 toxin were observed compared with DON on plant and mammalian cells. Nevertheless, significant stability difference is observed between NX-3 and DON in bread baking process, the stability of NX toxins reduced strongly compared with DON. Potential impacts of global warming on NX strains and mycotoxin production are discussed. Furthermore, genes involved in NX biosynthesis, and their functions are discussed, and potential pathways of NX toxins biosynthesis are proposed in our knowledge of trichothecene biosynthesis. This review should contribute to the current situation and future trends of the toxigenic Fusarium population and the emerging trichothecenes.

Polybrominated diphenyl ethers (PBDEs) are persistent organic pollutants. They are constantly detected in terrestrial, ocean, and atmospheric systems, and it is of particular concern that these fat-soluble xenobiotics may have a negative impact on human health. This study aimed to evaluate the toxic effect and underlying mechanism of decabromodiphenyl ether (BDE-209) on human liver in a HepG2 cell model. The results showed that BDE-209 significantly induced HepG2 cells apoptosis, increased intracellular reactive oxygen species (ROS), disturbed [Ca 2+] homeostasis and mitochondrial membrane potential (MMP), and caused nuclear shrinkage and DNA double-strand breaks. BDE-209 also significantly decreased the activities of antioxidant parameters, superoxide dismutase (SOD), total antioxygenic capacity (T-AOC), glutathione (GSH), and total glutathione (T-GSH). The up-regulation of the Aryl hydrocarbon receptor (AhR)/cytochrome P4501A1 (CYP1A1) signaling pathway indicates that after long-term and high-dose exposure, BDE-209 may be a liver carcinogen. Interestingly, HepG2 cells attempt to metabolize BDE-209 through the Nrf2-mediated antioxidant pathway. These findings help elucidate the mechanisms of BDE-209-induced hepatotoxicity in humans.

A new protein channel family Exposure of cells to acidic conditions outside the cell activates chloride-conducting channels that influence physiological and pathological processes. Yang et al. used an unbiased RNA interference screen to identify the channel protein that allows such proton-activated ion conductance. The protein, called PAC for proton-activated channel, has two predicted transmembrane domains and is unlike any previously identified channel. Identification of the channel should advance studies of its physiological roles, which range from tissue injury after stroke to adaptation of Tibetan natives to a high-altitude environment. Science , this issue p. 395

Masked mycotoxins are biologically modified phase II metabolites formed by plant defense mechanisms through glucosylation catalyzed by uridine diphosphate -glucosyltransferases. Most of the current reports focus on the occurrence of masked mycotoxins in Europe, America, Africa, and cover other geographic regions, e.g. China and Japan. High proportions of masked mycotoxins co-occurring with their parent forms in various cereal-based food and feedstuff could clearly increase total exposures and pose additional health risks to humans and animals. In contrast to the parent mycotoxins, the data on the toxicity of masked mycotoxins are still scarce, however, the poor existing information showed that masked mycotoxins generally exhibit significant in vitro and in vivo toxicities lower than those of their parent forms, especially for deoxynivalenol-3-glucoside, which is the only thoroughly investigated masked mycotoxin. Although the lower toxicity level of masked mycotoxins, these are probably hydrolyzed into their free forms by intestinal microorganisms in the digestive tract of mammals and thus contribute to unpredicted toxicity. The metabolic characteristics of reported masked mycotoxins are species-specific. The most relevant animal model of human sensitivity, the pig, is most sensitive to masked mycotoxins. This review focuses on updates in the current knowledge on country-specific natural-occurrence data in global surveys, as well as in vitro and in vivo toxicology and metabolic investigations of masked mycotoxins.

Background: CircRNAs have been found to play a crucial role in the pathological process of various kinds of diseases. However, the role of circRNAs in the formation and rupture of intracranial aneurysm is still unknown.Methods: Differentially expressed circRNAs profiles between superficial temporal arteries (n = 5) and intracranial aneurysms (n = 5) were analyzed using the Arraystar human circRNAs microarray. Quantitative real-time PCR was utilized to validate the differential expression of circDUS2. Fluorescence in situ hybridization (FISH) was meant for the location of circDUS2 in human brain vascular smooth muscle cell (HBVSMC). Structural analysis was used to speculate on the function of circDUS2.Results: Five hundred forty-three upregulated and 397 downregulated significantly in intracranial aneurysm as compared to superficial temporal arteries. Quantitative real-time PCR verified the elevated expression of the upregulated circDUS2. The FISH test revealed that circDUS2 is located in the cytoplasm of brain vascular smooth muscle cells.Conclusion: This study showed differential expression data of circRNAs between superficial temporal artery and intracranial aneurysm and revealed that circDUS2 is a potential molecular marker for intracranial aneurysm.

The wide usage of decabromodiphenyl ether (BDE-209) results in its increasing occurrence in the environment and increasing attention in regard to human and animal health. BDE-209 is an endocrine disruptor for hypothyroidism, but the toxicity mechanism is unclear. Here, the histopathology and transcriptome sequencing of thyroid tissue from broiler chicks were investigated by supplemental feeding with different concentrations of BDE-209 for 42 days (0–4 g/kg in basal diet), followed by determining the levels of thyroid hormones in serum. The results showed ruptured and even hyperplastic follicular epithelial cells in the thyroid, and a total of 501 differentially expressed genes were screened out: 222 upregulated and 279 downregulated. Based on the Kyoto Encyclopedia of Genes and Genomes database, neuroactive ligand-receptor interaction pathway was significantly enriched, and α1D-adrenergic receptor, follicle-stimulating hormone receptor, thyroid stimulating hormone receptor, and somatostatin receptor type 2 were shown to be candidate biomarkers. Thyroxine was a possible biomarker due to clear reduction in serum and significant correlation with exposure concentrations. These results suggested that oral intake of BDE-209 can cause structural injuries and even hyperplasia, and affect gene transcription involved in the neuroactive ligand-receptor interaction pathway of thyroid, as well as thyroid hormones in serum.

Simple Summary Decabrominated diphenyl ether (BDE-209) has been widely used in recent decades, and its cumulative toxicity to crops, animals and human beings is attracting increasing attention. In this study, we established broiler models to investigate the effects of BDE-209 exposure at doses of 0, 0.02, 0.4 and 4 mg/kg on growth, carcass traits, meat quality, blood profiles and antioxidant capacity. Our results suggested that BDE-209 exposure altered the blood profiles and carcass traits and exhibited toxicity in liver and kidney functions. Furthermore, BDE-209 increased plasma malondialdehyde (MDA) concentrations and decreased the activities of glutathione peroxidase (GSH-px) and superoxide dismutase (SOD), which implied aggravating oxidant stress and decline of antioxidant capacity in broilers. Abstract Decabrominated diphenyl ether (BDE-209) is widely used as a flame retardant and is detected at high levels in the environment. Its toxicities have been reported and have attracted attention. In the present study, broilers were used to determine the response in growth performance, carcass traits, meat quality, blood profiles and antioxidant system to BDE-209 exposure at doses of 0, 0.02, 0.4 and 4 mg/kg. The results showed that BDE-209 exposure at levels of 0.02 or 0.4 mg/kg increased feed intake and decreased feed efficiency. BDE-209 altered the blood profiles, such as reducing the numbers of white blood cells, lymphocytes and neutrophilic granulocytes. As compared with the control, BDE-209 exposure significantly increased abdominal fat percentages of broilers at 64.9–159.5% and adversely affected the selected biochemical indicators, including alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine (CRE), which indicated its toxicity to liver and kidney functions. Moreover, BDE-209 exposure significantly increased plasma malondialdehyde (MDA) concentrations and decreased the activities of glutathione peroxidase (GSH-px) and superoxide dismutase (SOD), which implied aggravating oxidant stress and decline of antioxidant capacity in broilers. In conclusion, our data demonstrated that the environmental pollutant BDE-209 adversely influenced growth performance, increased the deposition of abdominal fat, impaired antioxidant capacity and the immune system and had potential toxicity to the liver and kidney of broilers.

Neonatal lipopolysaccharide (LPS) exposure can lead to depressive-like behaviors in mice through inducing pro-inflammatory cytokines including interferon(IFN)-{gamma}. ATP8A2 is a phospholipid transporter located on the cell membrane. Studies have shown that the decrease in ATP8A2 expression in the prefrontal cortex (PFC) is associated with depressive behavior. Moreover, it has been reported that IFN-{gamma} could reduce ATP8A2 expression in non-neuronal cells. These findings prompted us to hypothesize that neonatal LPS exposure might induce ATP8A2 down-regulation in PFC in mice by increasing the IFN-{gamma} level. Mice pups consisting approximately evenly of both sexes were intraperitoneally injected with 3 doses of LPS (50 g/kg body weight for each dose) on postnatal day (PND5), PND7 and PND9. Here, we first found that PFC ATP8A2 expression decreased significantly and transiently till ten days after neonatal LPS exposure with the lowest level at two days after it. Moreover, a negative correlation of PFC ATP8A2 expression was found with the PFC level of IFN-{gamma}, rather than the other LPS-induced pro-inflammatory cytokines. Using anti-IFN-{gamma} neutralizing mAb, IFN-{gamma} was identified as the key mediator of LPS-induced ATP8A2 down-regulation in PFC in mice. Besides, neutralizing IFN-{gamma} partially but significantly rescued the depressive-like behaviors in adulthood induced by neonatal LPS exposure. In sum, the present study showed that neonatal LPS exposure induced ATP8A2 down-regulation in PFC and depressive-like behaviors in mice through increasing the IFN-{gamma} level.

SUMMARY During vesicular acidification, chloride (Cl−), as the counterion, provides the electrical shunt for proton pumping by the vacuolar H+ ATPase. Intracellular CLC transporters mediate Cl− influx to the endolysosomes through their 2Cl−/H+ exchange activity. However, whole-endolysosomal patch-clamp recording also revealed a mysterious conductance releasing Cl− from the lumen. It remains unknown whether CLCs or other Cl− channels are responsible for this activity. Here, we show that the newly identified proton-activated Cl− (PAC) channel traffics from the plasma membrane to endosomes via the classical YxxL motif. PAC deletion abolishes the endosomal Cl− conductance, raises luminal Cl− level, lowers luminal pH, and increases transferrin receptor-mediated endocytosis. PAC overexpression generates a large endosomal Cl− current with properties similar to those of endogenous conductance, hypo-acidifies endosomal pH, and reduces transferrin uptake. We propose that the endosomal Cl− PAC channel functions as a low pH sensor and prevents hyper-acidification by releasing Cl− from the lumen., Graphical Abstract, In Brief Osei-Owusu et al. show that the recently identified proton-activated chloride (PAC) channel traffics from the plasma membrane to endosomes and forms an intracellular organelle Cl− channel. PAC functions as a low pH sensor in endosomes and prevents luminal hyper-acidification.

Animal models of Down syndrome (DS), trisomic for human chromosome 21 (HSA21) genes or orthologs, provide insights into better understanding and treatment options. The only existing transchromosomic (Tc) mouse DS model, Tc1, carries a HSA21 with over 50 protein coding genes (PCGs) disrupted. Tc1 is mosaic, compromising interpretation of results. Here, we “clone” the 34 MB long arm of HSA21 (HSA21q) as a mouse artificial chromosome (MAC). Through multiple steps of microcell-mediated chromosome transfer, we created a new Tc DS mouse model, Tc(HSA21q;MAC)1Yakaz (“TcMAC21”). TcMAC21 is not mosaic and contains 93% of HSA21q PCGs that are expressed and regulatable. TcMAC21 recapitulates many DS phenotypes including anomalies in heart, craniofacial skeleton and brain, molecular/cellular pathologies, and impairments in learning, memory and synaptic plasticity. TcMAC21 is the most complete genetic mouse model of DS extant and has potential for supporting a wide range of basic and preclinical research.

Glioma-associated oncogene family zinc finger 2 (Gli2), a key component of the hedgehog signaling pathway, has been previously demonstrated to promote the malignant properties of prostate cancer in vitro. However, the role of Gli2 in the development of castration-resistant prostate cancer (CRPC) has yet to be fully elucidated. In the present study, Gli2 expression was knocked down in androgen-responsive prostate cancer cells using an inducible Gli2 short hairpin RNA. Suppression of Gli2 expression resulted in significant reduction of cell viability, increased the proportion of cells in the G0/G1 phases of the cell cycle and reduced the expression of genes associated with cell cycle progression. Gli2 knockdown sensitized both androgen-dependent and -independent prostate cancer cells to the antiandrogen drug Casodex and prevented the outgrowth of LNCaP prostate cancer cells. In addition, Gli2 knockdown significantly suppressed the development of CRPC in a LNCaP xenograft mouse model, which was reversed by the re-expression of Gli2. In conclusion, to the best of our knowledge, the present study was the first occasion in which the essential role of Gli2 in the development of CRPC was demonstrated, providing a potential therapeutic target for the intervention of CRPC.

We report the case of a thirty-eight-year-old woman admitted to our hospital due to palpitation and chest distress. ST-T segment change was found in her ECG. She was then diagnosed with hypertrophic cardiomyopathy by two-dimensional echocardiography. Physical examination showed no obvious abnormal signs and all laboratory examinations were within the normal range. Myocardial fibrosis was detected by cardiac magnetic resonance imaging (MRI). A novel heterozygous mutation (c.235C>T/p.Arg79Cys) in TNNI3 for cardiac troponin I was identified in her. Subsequently, her families were investigated. No one died suddenly in her family. Her father, one of her siblings and one of her daughters had the same genetic mutation but with different clinical manifestations while the others were healthy. Her father and brother were also diagnosed with hypertrophic cardiomyopathy with different clinical manifestation. However, the echocardiography of her daughter was absolutely normal. We hypothesized that the Arg79Cys mutation in TNNI3 leads to a slow development of cardiac hypertrophy and the phenotype of this gene mutation is diverse.

Down syndrome (DS) is a complex human condition, and animal models trisomic for human chromosome 21 (HSA21) genes or orthologs provide insights into better understanding and treating DS. However, HSA21 orthologs are distributed into three mouse chromosomes, preventing us from generating mouse models trisomy of a complete set of HSA21 orthologs. The only existing humanized mouse DS model, Tc1, carries a HSA21 with over 20% of protein coding genes (PCGs) disrupted. More importantly, due to the human centromere, Tc1 is mosaic (a mix of euploid and trisomic cells), which makes every mouse unique and compromises interpretation of results. Here, we used mouse artificial chromosome (MAC) technology to “clone” the 34 MB long arm of HSA21 (HSA21q). Through multiple steps of microcell-mediated chromosome transfer we created a new humanized DS mouse model, Tc(HSA21q;MAC)1Yakaz (“TcMAC21”). Constitutive EGFP expression from the transchromosome and fluorescent in situ hybridization validate that TcMAC21, containing a hybrid chromosome of HSA21q and mouse centromere, is not mosaic. Whole genome sequencing shows that TcMAC21 contains a nearly complete copy of HSA21q with 93% of intact PCGs, while RNA-seq and additional mRNA/protein expression analyses confirm that PCGs are transcribed and regulated. A battery of tests show that TcMAC21 recapitulates many DS phenotypes including morphological anomalies in heart, craniofacial skeleton and brain, pathologies at molecular and cellular level, and impairments in learning, memory and synaptic plasticity. TcMAC21 is the most complete mouse model of DS extant and has potential for supporting a wide range of basic and preclinical research.Significance StatementIn the last 25 years, mouse models of trisomy 21 have supported research into Down syndrome, from defining the basis for developmental effects up to support for clinical trials. However, existing models have significant shortfalls, especially for preclinical studies. These deficiencies include incomplete or inappropriate representation of trisomic genes, absence of an extra chromosome, and mosaicism.Using cutting edge technologies we produced a mouse artificial chromosome containing the entire 34Mb long arm of human chromosome 21 and, with assisted reproductive technologies, established it in the germ line of mice. This trisomic mouse manifests developmental and functional features of Down syndrome, including hippocampal-based learning and memory deficits. This is the most complete model of Down syndrome produced to date.

Hexanucleotide GGGGCC repeat expansion in C9ORF72 is the most prevalent genetic cause ofamyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). One pathogenic mechanism isthe aberrant accumulation of dipeptide repeat (DPR) proteins produced by the unconventional translation of expanded RNA repeats. Here, we performed genome-wide CRISPR-Cas9 screens for modifiers of DPR protein production in human cells.We found that DDX3X, an RNA helicase, suppresses the repeat-associated non-AUG translation of GGGGCC repeats. DDX3X directly binds to (GGGGCC)n RNAs but not antisense (CCCCGG)n RNAs. Its helicase activity is essential for the translation repression. Reduction of DDX3X increases DPR levels in C9ORF72-ALS/FTD patient cells and enhances (GGGGCC)n-mediated toxicity in Drosophila. Elevating DDX3X expression is sufficient to decrease DPR levels, rescue nucleocytoplasmic transport abnormalities, and improve survival of patient iPSC-differentiated neurons. This work identifies genetic modifiers of DPR protein production and provides potential therapeutic targets for C9ORF72-ALS/FTD.

Deoxynivalenol (DON) is one of the major mycotoxins that contaminate cereals. In this study, we determined the DON level in wheat-based products from Chinese five main production areas collected in Shanghai and calculated the daily intake of DON for inhabitants using the point evaluation and the probabilistic evaluation based on Monte Carlo simulation. The results showed the positive rates of DON in the products were higher than 80.0%, with the concentrations ranging from 41.8 to 1110 µg/kg. The estimated mean daily intakes of DON for 7- to 10-year-old children and adults groups were below 1 µg/kg bw/day, the provisional maximum tolerable daily intake (PMTDI) set by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), suggesting no health risks for the consumers. However, the 99th percentiles of dietary DON exposures for children and adults exceeded the PMTDI, indicating adverse health effects might occur if the two groups intake highly contaminated wheat-based products. The potential health risks for the two groups exposed to DON in the wheat-based products from the Middle and Lower Yangtze Valley (MLYV) were higher than those from the other areas in China.

Fusarium blight of wheat is usually caused by Fusarium graminearum, and the pathogenic fungi will secrete effectors into the host plant tissue to affect its normal physiological process, so as to make it pathogenic. The CFEM (Common in Fungal Extracellular Membrane) protein domain is unique to fungi, but it is not found in all fungi. The CFEM protein contained in F. graminearum may be closely related to pathogenicity. In this study, 23 FgCFEM proteins were identified from the F. graminearum genome. Then, features of these proteins, such as signal peptide, subcellular localization, and transmembrane domains, etc., were analyzed and candidate effectors were screened out. Sequence alignment results revealed that each FgCFEM protein contains one CFEM domain. The amino acids of the CFEM domain are highly conserved and contain eight spaced cysteines, with the exception that FgCFEM8, 9, and 15 lack two cysteines and three cysteines were missed in FgCFEM18 and FgCFEM22. A recently identified CFEM_DR motif was detected in 11 FgCFEMs, and importantly we identified two new conserved motifs containing about 29 and 18 amino acids (CFEM_WR and CFEM_KF), respectively, in some of FgCFEM proteins. Transcriptome analysis of the genes encoding CFEM proteins indicated that all the CFEM-containing genes were expressed during wheat infection, with seven and six genes significantly up- and down-regulated, respectively, compared with in planta and in vitro. Based on the above analysis, FgCFEM11 and FgCFEM23 were predicted to be F. graminearum effectors. This study provides the basis for future functional analyses of CFEM proteins in F. graminearum.

Transplantation of microbiota from small intestine, not large intestine, of healthy mice exerts obvious effects on healthy recipients, bringing a new perspective on gut flora transplantation., Fecal microbiota transplantation is widely used. Large intestinal microbiota (LIM) is more similar to fecal microbiota than small intestinal microbiota (SIM). The SIM communities are very different from those of LIM. Therefore, SIM transplantation (SIMT) and LIM transplantation (LIMT) might exert different influences. Here, healthy adult male C57Bl/6 mice received intragastric SIMT, LIMT, or sterile PBS administration. Microbiota graft samples were collected from small/large intestine of healthy mice of the same age, sex, and strain background. Compared with PBS treatment, SIMT increased pellet number, stool wet weight, and stool water percentage; induced a fecal microbiota profile shift toward the microbial composition of the SIM graft; induced a systemic anti-inflammatory cytokines profile; and ameliorated depressive-like behaviors in recipients. LIMT, however, induced merely a slight alteration in fecal microbial composition and no significant influence on the other aspects. In sum, SIMT, rather than LIMT, affected defecation features, fecal microbial composition, cytokines profile, and depressive-like behaviors in healthy mice. This study reveals the different effects of SIMT and LIMT, providing an interesting clue for further researches involving gut microbial composition change.

Deoxynivalenol (DON, vomitoxin) is the most common mycotoxin in cereals and grains. DON contamination can cause a serious health threat to humans and farm animals. DON has been reported to exert significant toxicity effects on the male reproductive system. However, the causes and mechanisms underlying efforts of DON on sperm and testicular damage remain largely unclear. In the present study, we thoroughly investigated this issue. Eighty male BALB/c mice were randomly divided into a control group ( n = 40) and DON treatment group (2.4 mg/kg of body weight, n = 40). The ratio of testes and seminal vesicle to body, sperm survival and motility, and morphology of sperm and testis were observed in DON-treated and control mice. In addition, the concentrations of reactive oxygen species (ROS) and malondialdehyde (MDA), the activities of superoxide dismutase (SOD) and glutathione (GSH), and also the expression levels of JNK/c-Jun signaling and apoptotic factors such as caspase-3, caspase-8, caspase-9, Bim, and Bid were analyzed and compared between the two groups. The results demonstrated that a single topical application of DON significantly increased the percentage of abnormal sperm and decreased the motility of sperm, indicating the sperms are damaged by DON. Additionally, the reduced relative body weight of testis and severe destruction of testicular morphology were observed. Moreover, the increased levels of ROS and MDA levels and decreased activities of SOD and GSH were found in testicular tissues, suggesting that oxidative stress is induced by DON treatment. Furthermore, DON upregulated the expression of stress-induced JNK/c-Jun signaling pathway proteins as well as JNK/c-Jun phosphorylation proteins. In addition, DON could enhance testicular apoptosis by increasing expression levels of apoptotic genes including Bim, cytochrome c, caspase 3, caspase 8, and caspase 9. These results suggest that DON exposure can cause sperm damage, oxidative stress, testicular apoptosis, and phosphorylation of JNK/c-Jun signaling pathway. The underlying mechanisms may be that DON induces sperm damage by exacerbating oxidative stress-mediated testicular apoptosis via JNK/c-Jun signaling pathway.

A simple and reliable analytical method for the simultaneous determination of alternariol (AOH), altenuene (ALT), tentoxin (TEN), altenusin (ALS), tenuazonic acid (TeA), and alternariol monomethyl ether (AME) in grapes was developed by ultra-high-performance liquid chromatography&ndash, tandem mass spectrometry (UHPLC-MS/MS). A modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure with the extraction by acetonitrile and purification by sodium chloride (0.5 g) and anhydrous magnesium sulfate (0.5 g) was established to recover the six Alternaria toxins. After validation by determining the linearity (R2 &gt, 0.99), recovery (77.8&ndash, 101.6%), sensitivity (limit of detection in the range of 0.03&ndash, 0.21 &mu, g kg&minus, 1, and limit of quantification in the range of 0.09&ndash, 0.48 &mu, 1), and precision (relative standard deviation (RSD) &le, 12.9%), the analytical method was successfully applied to reveal the contamination state of Alternaria toxins in grapes. Among 56 grape samples, 40 (incidence of 71.4%) were contaminated with Alternaria toxins. TEN was the most frequently found mycotoxin (37.5%), with a concentration range of 0.10&ndash, 1.64 &mu, 1, followed by TeA (28.6%) and AOH (26.8%). ALT (10.7%), AME (3.6%), and ALS (5.4%) were also detected in some samples. To the best of our knowledge, this is the first report about the Alternaria toxins contamination in grapes in China.

// Tai Qin 1, 2 , Lindsey Barron 1 , Lu Xia 1, 3 , Haojie Huang 5 , Maria M. Villarreal 4 , John Zwaagstra 9 , Cathy Collins 9 , Junhua Yang 1 , Christian Zwieb 4 , Ravindra Kodali 8 , Cynthia S. Hinck 8 , Sun Kyung Kim 4 , Robert L. Reddick 6 , Chang Shu 2 , Maureen D. O’Connor-McCourt 9 , Andrew P. Hinck 8 , Lu-Zhe Sun 1, 7 1 Department of Cell Systems and Anatomy, University of Texas Health Science Center, San Antonio, TX, USA 2 Department of Vascular Surgery, Second Xiangya Hospital and Xiangya School of Medicine, Central South University, Hunan, China 3 Department of Gynecology and Obstetrics, Xiangya Hospital and Xiangya School of Medicine, Central South University, Hunan, China 4 Department of Biochemistry, University of Texas Health Science Center, San Antonio, TX, USA 5 Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, MN, USA 6 Department of Pathology, University of Texas Health Science Center, San Antonio, TX, USA 7 Cancer Therapy and Research Center, University of Texas Health Science Center at San Antonio, Texas, USA 8 Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA USA 9 National Research Council Human Health Therapeutics Portfolio, Montreal, Quebec, Canada, Maureen O'Connor-McCourt is currently affiliated with Formation Biologics, Montreal, Quebec, Canada Correspondence to: Lu-Zhe Sun, email: SUNL@uthscsa.edu Andrew P. Hinck, email: ahinck@pitt.edu Keywords: TGF-β trap, RER, tumorigenesis, Pten, prostate cancer Received: August 15, 2016 Accepted: November 07, 2016 Published: November 14, 2016 ABSTRACT The effects of transforming growth factor beta (TGF-β) signaling on prostate tumorigenesis has been shown to be strongly dependent on the stage of development, with TGF-β functioning as a tumor suppressor in early stages of disease and as a promoter in later stages. To study in further detail the paradoxical tumor-suppressive and tumor-promoting roles of the TGF-β pathway, we investigated the effect of systemic treatment with a TGF-β inhibitor on early stages of prostate tumorigenesis. To ensure effective inhibition, we developed and employed a novel trivalent TGF-β receptor trap, RER, comprised of domains derived from the TGF-β type II and type III receptors. This trap was shown to completely block TβRII binding, to antagonize TGF-β1 and TGF-β3 signaling in cultured epithelial cells at low picomolar concentrations, and it showed equal or better anti-TGF-β activities than a pan TGF-β neutralizing antibody and a TGF-β receptor I kinase inhibitor in various prostate cancer cell lines. Systemic administration of RER inhibited prostate tumor cell proliferation as indicated by reduced Ki67 positive cells and invasion potential of tumor cells in high grade prostatic intraepithelial neoplasia (PIN) lesions in the prostate glands of Pten conditional null mice. These results provide evidence that TGF-β acts as a promoter rather than a suppressor in the relatively early stages of this spontaneous prostate tumorigenesis model. Thus, inhibition of TGF-β signaling in early stages of prostate cancer may be a novel therapeutic strategy to inhibit the progression as well as the metastatic potential in patients with prostate cancer.

The correlation of genetic polymorphisms of GALNT3 and vitamin D receptor (VDR) with osteoporosis in postmenopausal women was investigated. A total of 1,212 cases of postmenopausal patients diagnosed with osteoporosis (observation group) and 404 cases of postmenopausal women without osteoporosis (control group) were selected. Dual-energy X-ray absorptiometry was used for measurement of bone mineral density (BMD) of lumbar vertebrae L2–4, proximal femoral neck and total hip, and classifications were made. TaqMan genotyping technology was employed to examine tag single-nucleotide polymorphism (tagSNP) of GALNT3 and VDR and the correlation of tagSNP with bone turnover markers (BTMs) and serum calcium and phosphorous levels was analyzed. The multiple logistic regression analysis was used to screen risk factors for osteoporosis. A comparison of age and menopause time of the two groups, yielded no statistical significance difference (P>0.05). BMD and T values of the lumbar vertebrae, femoral neck and total hip in the observation group were significantly lower than those in the control group, and the differences were statistically significant (P

// Zhao Liu 1,2,4 , Long Wang 2 , Junhua Yang 2 , Abhik Bandyopadhyay 2 , Virginia Kaklamani 3 , Shui Wang 1 and Lu-Zhe Sun 2,3 1 Department of Breast Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China 2 Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, Texas, United States of America 3 Cancer Therapy and Research Center, University of Texas Health Science Center at San Antonio, Texas, United States of America 4 Department of Thyroid and Breast Surgery, Affiliated Hospital of Xuzhou Medical College, Xuzhou, China Correspondence to: Shui Wang, email: // Lu-Zhe Sun, email: // Keywords : estrogen receptor alpha; senescence; transformation; ras; Gerotarget Received : November 18, 2015 Accepted : May 20, 2016 Published : June 01, 2016 Abstract Exposure to estrogen has long been associated with an increased risk of developing breast cancer. However, how estrogen signaling promotes breast carcinogenesis remains elusive. Senescence is known as an important protective response to oncogenic events. We aimed to elucidate the role of estrogen receptor alpha (ERα) on senescence in transformed human mammary epithelial cells and breast cancer cells. Our results show that ectopic expression of oncoprotein H-ras-V12 in immortalized human mammary epithelial cells (HMEC) significantly inhibited the phosphorylation of the retinoblastoma protein (Rb) and increased the activity of the senescence-associated beta-galactosidase (SA-β-Gal). These senescence-like phenotypes were reversed by ectopic expression of ERα. Similar inhibition of the H-ras-V12-induced SA-β-Gal activity by ERα was also observed in the human mammary epithelial MCF-10A cells. Co-expression of ERα and H-ras-V12 resulted in HMEC anchorage-independent growth in vitro and tumor formation in vivo . Furthermore, inhibition of ERα expression induced senescence-like phenotypes in ERα positive human breast cancer cells such as increased activity of SA-β-Gal, decreased phosphorylation of RB, and loss of mitogenic activity. Thus, the suppression of cellular senescence induced by oncogenic signals may be a major mechanism by which ERα promotes breast carcinogenesis.

Innate fear has a critical role in survival of animals. Unlike conditioned fear, the neuronal circuitry underlying innate fear is largely unknown. We found that the laterodorsal tegmentum (LDT) and lateral habenula (LHb) are specifically activated by the mouse predator odorant trimethylthiazoline (TMT). Using optogenetics to selectively stimulate GABAergic neurons in the LDT immediately produced fear-like responses (freezing, accelerated heart rate and increased serum corticosterone), whereas prolonged stimulation caused anxiety-like behaviors. Notably, although selective stimulation of parvalbumin (PV)-positive interneurons similarly induced fear-like responses, stimulation of somatostatin-positive interneurons or inhibition of PV neurons in the LDT suppressed TMT-induced fear-like responses without affecting conditioned fear. Finally, activation of LHb glutamatergic inputs to LDT interneurons was sufficient to generate fear-like responses. Thus, the LHb-LDT pathway is important for regulating olfactory cue-induced innate fear. Our results provide a potential target for therapeutic intervention for anxiety disorder.

A reliable and large-scale preparative method was developed for the simultaneous preparation of high-purity fumonisin B1 (FB1), fumonisin B2 (FB2) and fumonisin B3 (FB3) from maize culture inoculated with Fusarium moniliforme in this study. The targeted B-series fumonisins (FBs) were firstly extracted with acetonitrile/water (50 : 50, v/v) and then purified using MAX cartridges. The subsequent chromatographic preparative procedures on a Unitary C18 column (250 mm × 10 mm, 5 μm) and a SB-CN column (250 mm × 9.4 mm, 5 μm) were performed to effectively eliminate the other interferents to obtain the high-purity compounds. The prepared compounds were clearly identified to be FB1, FB2 and FB3 using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and nuclear magnetic resonance (NMR). The purities were 96.25 ± 0.18%, 98.07 ± 0.18% and 97.36 ± 0.74% for FB1, FB2 and FB3, respectively, which were determined by the external standard LC-MS/MS method. Within 72 h, large amounts of high-purity FB1 (80 mg), FB2 (16 mg) and FB3 (16 mg) could be simultaneously prepared by the established approach.

Bacillus Calmette-Guérin (BCG) is administered to neonates worldwide, but it is still unknown whether this neonatal vaccination affects brain development during early postnatal life, despite the close association of the immune system with the brain. Newborn C57BL/6 mice were injected subcutaneously with BCG or phosphate-buffered saline (PBS) and their mood status and spatial cognition were observed at four and eight weeks (w) old. The mice were also subjected to tests at 2 and 6 w to examine BCG's effects on neurogenesis, the hippocampal microglia phenotype and number, and the expression of hippocampal neuroimmune molecules and peripheral cytokines. The BCG-injected mice showed better behavioral performances at 4 w. We observed elevated neurogenesis, M2 microglial activation and a neurotrophic profile of neuroimmune molecules [more interferon (IFN)-γ, interleukin (IL)-4, transforming growth factor (TGF)-β, brain-derived neurotrophic factor (BDNF) and insulin-like growth factor (IGF)-1 and less tumor necrosis factor (TNF)-α and IL-1β] in the hippocampus of the 2-w-old BCG-mice. In the periphery, BCG induced a T helper (Th)-1 serum response. At the individual level, there were positive correlations between the serum IFN-γ/IL-4 ratio and the levels of neurotrophins and neurogenesis in the hippocampus. These findings suggest that neonatal BCG vaccination improved neurogenesis and mouse behavior in early life by affecting the neuroimmune milieu in the brain, which may be associated with a systemic Th1 bias.

Impaired amyloid-β clearance from the brain is a core pathological event in Alzheimer's disease. The therapeutic effect of current pharmacotherapies is unsatisfactory, and some treatments cause severe side effects. The meningeal lymphatic vessels might be a new route for amyloid-β clearance. This study investigated whether promoting dural lymphangiogenesis facilitated the clearance of amyloid-β from the brain. First, human lymphatic endothelial cells were treated with 100 ng/mL recombinant human vascular endothelial growth factor-C (rhVEGF-C) protein. Light microscopy verified that rhVEGF-C, a specific ligand for vascular endothelial growth factor receptor-3 (VEGFR-3), significantly promoted tube formation of human lymphatic endothelial cells in vitro. In an in vivo study, 200 μg/mL rhVEGF-C was injected into the cisterna magna of APP/PS1 transgenic mice, once every 2 days, four times in total. Immunofluorescence staining demonstrated high levels of dural lymphangiogenesis in Alzheimer's disease mice. One week after rhVEGF-C administration, enzyme-linked immunosorbent assay results showed that levels of soluble amyloid-β were decreased in cerebrospinal fluid and brain. The Morris water maze test demonstrated that spatial cognition was restored. These results indicate that the upregulation of dural lymphangiogenesis facilities amyloid-β clearance from the brain of APP/PS1 mice, suggesting the potential of the VEGF-C/VEGFR-3 signaling pathway as a therapeutic target for Alzheimer's disease.

Immune activation can exert multiple effects on synaptic transmission. Our study demonstrates the influence of neonatal vaccination on hippocampal synaptic plasticity in rats under normal physiological conditions. The results revealed that neonatal BCG vaccination enhanced synaptic plasticity. In contrast, HBV hampered it. Furthermore, we found that the cytokine balance shifted in favour of the T helper type 1/T helper type 2 immune response in BCG/HBV-vaccinated rats in the periphery. The peripheral IFN-γ:IL-4 ratio was positively correlated with BDNF and IGF-1 in the hippocampus. BCG raised IFN-γ, IL-4, BDNF and IGF-1 and reduced IL-1β, IL-6, and TNF-α in the hippocampus, whereas, HBV triggered the opposite effects.

Intracellular Ca(2+) elevation resulting from different Ca(2+) pathways may play different roles in astrocyte functions. Channelrhodopsin-2 (ChR2), a light-gated cation channel, has been used to selectively stimulate astrocytes by inducing intracellular Ca(2+) ([Ca(2+)]i) elevation, but the exact underlying mechanism is still unclear. We found that in the absence of extracellular Ca(2+), light stimulation failed to induce [Ca(2+)]i elevation in astrocytes expressed ChR2. Pharmacological experiments excluded the involvement of Ca(2+)-induced Ca(2+) release from intracellular stores. Further experiments demonstrated that the ChR2-induced [Ca(2+)]i elevation was mainly mediated by reversal of the Na(+)-Ca(2+) exchanger following Na(+) influx through ChR2 channels. Since intracellular Na(+) homeostasis plays important roles in astrocytes, including the modulation of [Ca(2+)]i, neurotransmitter uptake and cell metabolism, our results indicate that ChR2 is a good candidate which could be used for mimicking the intracellular Na(+) disturbance in astrocytes that occurs in various physiological and pathological processes including the uptake of neurotransmitters and ischemia, as well as the activities of various cation channels, ion exchangers, and pumps.

The common pathological hallmark of Alzheimer’s disease (AD) is β-amyloid plaque deposition. The ideal therapy would reduce the Aβ burden with a low inflammatory immune response. Passive immunotherapy is an advanced treatment that dramatically reduces brain Aβ pathologies in AD animal models. The objective of our study was to observe the effects of 5C8H5, a novel monoclonal antibody derived from 4Aβ1-15, on brain Aβ pathology in an APP/PS1 mouse model of AD. Six-month-old transgenic mice were administered 5C8H5, 4Aβ1-15 or IgG, and same-aged wild-type untreated C57Bl/6J mice were employed as controls. Inflammatory factors and Aβ40/42 levels were detected by ELISA, while Aβ plaques, microglial cell activation, microhemorrhages and neurogenesis were evaluated by immunohistochemical staining. Compared with 4Aβ1-15-treated mice, the mice in the 5C8H5 group induced more Aβ clearance with less microglial cell activation in a niche of Th2-polarized immune response. The levels of proinflammatory factors, including IL-1β, IL-6, TNF-α and IFN-γ, were significantly decreased in the CNS, while the level of antiinflammatory IL-4 was increased. Moreover, the mice in the 5C8H5 group induced more neurogenesis without microhemorrhage exacerbation and thereby performed better in behavioral assays than did the 4Aβ1-15 group. In conclusion, the novel monoclonal antibody induces more Aβ clearance and less microglial cell activation in the absence of inflammation, accompanied by an increased Th2-polarized immune response, which makes it a more promising therapeutic strategy. These data provide evidence that passive immunity could alleviate pathologic Aβ alterations by modulating inflammation and should be pursued further for the treatment of AD.

In addition to cortical areas, the thalamus also displays plasticity during a critical period in early life. Since most sensory information is transmitted to the cortex via the thalamus, it will be of significant interest to understand the precise time window and underlying mechanisms of this critical period in the thalamus. By using in vitro whole-cell patch recording in acute brain slices, we found that VPm relay synapses were only sensitive to whisker deprivation from postnatal day 11 (P11) to P14. Whisker deprivation initiated within the P11 to P14 window significantly reduced the amplitude of AMPAR-EPSCs, but not NMDAR-EPSCs when recorded 24 hours after whisker removal. From P10 to P11, the timing for entry into the critical period and the kinetics underlying NMDAR-EPSCs function were significantly altered. At P11, NMDAR-EPSCs were less sensitive to ifenprodil, a selective blocker of NR2B-containing NMDAR, and the protein level of NR2A was significantly increased compared to those at P10. At the end of the critical period there were no obvious changes in synaptic properties when compared between P14 and P15. Using calcium imaging, we found that fewer P15 VPm neurons could be excited by the GABAa receptor agonist, muscimol, when compared to P14 VPm neurons; this correlated to an increase in KCC2 expression. Our studies revealed a precise critical period of sensory experience-dependent plasticity in the thalamus featuring distinct molecular mechanisms which occur at the start and end of this critical window.

Corin is a serine protease that activates atrial natriuretic peptide (ANP). CORIN gene variants have been reported in patients with hypertension. To date, however, the prevalence of CORIN variants in hypertensive patients remains unknown. To understand the prevalence and functional significance of CORIN variants in hypertension, we sequenced CORIN exons in 300 normal and 401 hypertensive individuals in a Chinese population and identified nine nonsynonymous variants, of which eight were not characterized previously. Among them, variants c.131A > G (p.Tyr13Cys), c.376G > T (p.Asp95Tyr), c.1094T > G (p.Leu334Trp), and c.1667G > A (p.Arg525His) occurred similarly in both normal and hypertensive individuals. Variants c1139G > A (p.Arg349His), c.2689C > T (p.Pro866Ser), and c.2864C > T (p.Thr924Met) were found once each in hypertensive individuals. Variant c.1683G > T (p.Arg530Ser) occurred preferentially in hypertensive individuals [10/401 (2.5%) vs. 1/300 (0.3%) in normal individuals; P = 0.023], which was confirmed in another independent cohort [9/368 (2.44%) in hypertensive and 2/377 (0.53%) in normal individuals; P = 0.033]. In biochemical and cell-based functional studies, variants p.Arg530Ser and p.Thr924Met, but not p.Tyr13Cys, p.Asp95Tyr, p.Leu334Trp, p.Arg349His, p.Arg525His, and p.Pro866Ser, exhibited reduced pro-ANP processing activity, which was caused by endoplasmic reticulum retention and poor zymogen activation, respectively. These results indicate that genetic variants impairing corin function are not uncommon in general populations and that such variants may be an important contributing factor in hypertension.

The aim of this study was to investigate the efficacy of selenium nanoparticles (SeNPs) that had been biologically synthesized by Bacillus licheniformis to counteract deoxynivalenol (DON) toxicity in laying hens. Ninety-six healthy, 20-week-old laying hens were randomly assigned to four treatment groups, each of which included 3 replicates of 8 layers, and fed four different diets: an uncontaminated basal diet (control group), a 10 mg/kg DON-contaminated basal diet (DON group), a 10 mg/kg DON-contaminated basal diet with 0.5 mg/kg SeNPs (DON+SeNPs group) and the basal diet with 0.5 mg/kg SeNPs (SeNPs group). Serum T-AOC and GPx activities were significantly decreased (P

Immunization with synthetic, preaggregated β-amyloid (Aβ) was the first treatment approach able to dramatically reduce brain Aβ pathology in Alzheimer's disease (AD) animal models. For the development of a safe vaccine, we investigated whether 4Aβ1-15 (four tandem repeats of GPGPG-linked Aβ1-15 sequences) had therapeutic effects in the APP/PS1 transgenic mice model of AD. We described the production of anti-Aβ antibodies in APP/PS1 mice immunized with 4Aβ1-15 mixed with MF59 adjuvant. The anti-Aβ antibody concentrations were increased which bound to AD plaques, markedly reduced Aβ pathology in transgenic AD mice and levels of intracerebral Aβ (soluble and insoluble), whereas increased serum Aβ levels. Immunization via 4Aβ1-15 (mainly of the IgG1 Class) may induce a non-inflammatory Th2 reaction. Immunohistochemistry analysis of MHC Class II and CD45 revealed that microglial cells were in a less activated state. Of note, 4Aβ1-15-immunized mice showed improved acquisition of memory compared with controls in a reference-memory Morris water-maze behavior test. The data identify the novel immunogen 4Aβ1-15 as a promising new tool for AD immunotherapy.

Neonatal Bacillus Calmette-Guerin (BCG) vaccination results in a positive effect on hippocampal neurogenesis and cognition. Serum cytokines are considered to be the chief culprit. In this study, serum from BCG-treated mice was identified as Th1 polarized serum. The serum showed an increased ratio of IFN-γ to IL-4 and decreased levels of TNF-α and IL-6. After Th1 polarized serum was injected intraperitoneally into postnatal mice, the levels of cytokines and ratio of IFN-γ to IL-4 in the serum and hippocampus of postnatal mice showed a similar alteration as those in Th1 polarized serum. This result indicated that the immune homeostatic milieu in postnatal mice was broken and the Th1 polarized systemic environment in the BCG-serum group was remodeled. The BCG-serum group displayed more BrdU+/DCX+ cells, BrdU+/NeuN+ cells, Nestin+ cells and better cognitive abilities. In neural stem cells, the Wnt7a/β-catenin signaling pathway was activated and exposure to the Wnt7a antagonist Dickkopf-1 inhibited BCG-serum-induced Wnt7a/β-catenin signaling, neurogenesis and cognitive function. Additionally, BCG-serum was associated with elevations in hippocampal brain-derived neurotrophic factor (BDNF) levels, and BDNF expression in the BCG-serum group was offset by Dickkopf-1 treatment. By rebalancing the Th1 polarized systemic environment in neonatal mice, it is possible that treatment with BCG-serum promotes hippocampal neurogenesis and improves cognitive functions, which are associated with Wnt7a/β-catenin-BDNF signaling.

Ectopic expression of lineage-specific transcription factors facilitates the conversion of mammalian somatic cells into dopaminergic (DA) neurons, which is a promising strategy for cell therapy of Parkinson's disease (PD). However, this approach still has some drawbacks limiting its clinical application due to the potential risks of integrating vectors into the host genome. Therefore, it is critical to seek a more desired approach to generate DA neurons derived from mammalian somatic cells. Here, we report that mouse embryonic fibroblasts (MEFs) can be efficiently converted into DA neurons by using small molecules along with specific growth factors. These neuron-like cells generate DA neuronal morphology, and acquire immunocytochemical and calcium imaging special for neuronal electrophysiological profile. More importantly, these converted cells can secrete dopamine, indicating that they are functionally similar to DA neurons. Taken together, our study might provide a promising cell source for treating PD by using chemical approach without introduction of exogenous transcription factors.

The immune system plays a vital role in brain development. The hepatitis B vaccine (HBV) is administered to more than 70% of neonates worldwide. Whether this neonatal vaccination affects brain development is unknown. Newborn C57BL/6 mice were injected intraperitoneally with HBV or phosphate-buffered saline. HBV induced impaired behavioral performances and hippocampal long-term potentiation at 8 weeks (w) of age without influence at 4 or 12w. At 6w, there was decreased neurogenesis, M1 microglial activation and a neurotoxic profile of neuroimmune molecule expression [increased tumor necrosis factor-α and reduced interferon (IFN)-γ, brain-derived neurotrophic factor and insulin-like growth factor-1] in the hippocampus of the HBV-vaccinated mice. In the serum, HBV induced significantly higher levels of interleukin (IL)-4, indicating a T helper (Th)-2 bias. Moreover, the serum IFN-γ/IL-4 ratio was positively correlated with the levels of neurotrophins and neurogenesis in the hippocampus at the individual level. These findings suggest that neonatal HBV vaccination of mice results in neurobehavioral impairments in early adulthood by inducing a proinflammatory and low neurotrophic milieu in the hippocampus, which follows the HBV-induced systemic Th2 bias.

Selective elimination of unwanted synapses is vital for the precise formation of neuronal circuits during development, but the underlying mechanisms remain unclear. Using inositol 1,4,5-trisphosphate receptor type 2 knockout (Itpr2−/−) mice to specifically disturb somatic Ca2+ signaling in astrocytes, we showed that developmental elimination of the ventral posteromedial nucleus relay synapse was impaired. Interestingly, intracerebroventricular injection of ATP, but not adenosine, rescued the deficit in synapse elimination in Itpr2−/− mice. Further studies showed that developmental synapse elimination was also impaired in P2ry1−/− mice and was not rescued by ATP, indicating a possible role of purinergic signaling. This hypothesis was confirmed by MRS-2365, a selective P2Y1 agonist, could also rescue the deficient of synapse elimination in Itpr2−/− mice. Our results uncovered a novel mechanism suggesting that astrocytes release ATP in an IP3R2-dependent manner to regulate synapse elimination. DOI: http://dx.doi.org/10.7554/eLife.15043.001, eLife digest Neighbouring neurons connect to each other and share information through structures known as synapses. As the brain develops, many synapses turn out to be redundant. Just like trees in a garden that need to be trimmed, these redundant synapses must be pruned in order to form the right pattern of connections between different neurons. Brain cells called astrocytes play a key role in synaptic pruning, but it is unclear exactly how astrocytes coordinate this process. One important way in which astrocytes communicate with neurons is through a process called calcium signaling, in which the movement of calcium ions into or out of the cell sets off a cascade of activity inside the astrocytes. Yang et al. have now studied developing mice that lacked a gene that is essential for calcium signaling in astrocytes. Two weeks after they were born, these mice still had redundant synapses that are normally lost after birth. However, injecting the developing brain with a substance called ATP prevented this defect and allowed synapses to be correctly pruned. This is likely to be because astrocytes also use ATP to communicate with neurons, and ATP compensated for the missing calcium signaling. The experiments also uncovered the specific structure – called the P2Y1 receptor – on the outer surface of a neuron that ATP latches on to in order to help remove synapses. Further work is now needed to reveal how activating the P2Y1 receptor coordinates synaptic removal. DOI: http://dx.doi.org/10.7554/eLife.15043.002

Mono-ADP-ribosyltransferase 2 (ART2) is found in mouse T cells and has mediated NAD-induced cell death (NICD) alongside the P2X7 pathway. We determined whether ART2 was expressed in mouse brain astrocytes and the possible function of the NAD-ART2-P2X7 pathway in astrocytes. Our results demonstrate that ART2 existed both in cultured mouse astrocytes and mouse brain slices. Exposure of astrocytes to the ART2 substrate, NAD, induced calcium elevation, which was blocked by ART2 and P2X7 inhibitors. ATP and NAD had an additive effect on calcium elevation. NICD in low-calcium conditions was blocked by ART2 and P2X7 inhibitors. The harmful effect of ATP on astrocytes was inhibited by P2X7 and ART2 inhibitors, meaning that endogenous NAD release may occur. Both NICD function and oxygen-glucose deprivation injury in mouse brain slices were also involved in the ART2-P2X7 pathway. Collectively, to our knowledge, our study provides the first evidence that ART2 exists in mouse brain astrocytes and NAD induces calcium elevation and astrocyte death by an ART2 and P2X7-mediated mechanism. The results suggest a novel approach for manipulating astrocyte death.

Biomarkers are lacking for identifying the switch of transforming growth factor-β (TGF-β) from tumor-suppressing to tumor-promoting. Mutated p53 (mp53) has been suggested to switch TGF-β to a tumor promoter. However, we found that mp53 does not always promote the oncogenic role of TGF-β. Here, we show that endogenous mp53 knockdown enhanced cell migration and phosphorylation of ERK in DU145 prostate cancer cells. Furthermore, ectopic expression of mp53 in p53-null PC-3 prostate cancer cells enhanced Smad-dependent signaling but inhibited TGF-β-induced cell migration by down-regulating activated ERK. Reactivation of ERK by the expression of its activator, MEK-1, restored TGF-β-induced cell migration. Because TGF-β is known to activate the MAPK/ERK pathway through direct phosphorylation of the adaptor protein ShcA and MAPK/ERK signaling is pivotal to tumor progression, we investigated whether ShcA contributed to mp53-induced ERK inhibition and the conversion of the role of TGF-β during carcinogenesis. We found that mp53 expression led to a decrease of phosphorylated p52ShcA/ERK levels and an increase of phosphorylated Smad levels in a panel of mp53-expressing cancer cell lines and in mammary glands and tumors from mp53 knock-in mice. By manipulating ShcA levels to regulate ERK and Smad signaling in human untransformed and cancer cell lines, we showed that the role of TGF-β in regulating anchorage-dependent and -independent growth and migration can be shifted between growth suppression and migration promotion. Thus, our results for the first time suggest that mp53 disrupts the role of ShcA in balancing the Smad-dependent and -independent signaling activity of TGF-β and that ShcA/ERK signaling is a major pathway regulating the tumor-promoting activity of TGF-β.

XiuFen Lei, Long Wang, Junhua Yang, Lu-Zhe SunDepartment of Cellular and Structural Biology, the University of Texas Health Science Center, San Antonio, TX 78229, USAAbstract: The association of mutation of the transforming growth factor beta (TGFβ) type II receptor (RII) with microsatellite instability revealed a significant molecular mechanism oftumorigenesis and tumor progression in gastrointestinal carcinomas with DNA replication error. However, mutation of RII is rare in other types of carcinomas with microsatellite instability including endometrial adenocarcinoma suggesting that TGFβ receptor signaling may be necessary for tumor progression. To test this hypothesis, we abrogated TGFβ signaling with ectopic expression of a dominant-negative RII (DNRII) in human endometrial carcinoma HEC-1-A cells with microsatellite instability. Our study showed that over-expression of DNRII blocked the TGFβ signaling, inhibited anchorage-dependent and -independent growth, and stimulated apoptosis in vitro. Interestingly, the expression of DNRII expression showed little effect on tumor growth of subcutaneously inoculated cells in vivo. On the other hand, the DNRII cells showed more epithelial features whereas the control cells showed more mesenchymal features suggesting a reversal of autocrine TGFβ-induced epithelial–mesenchymal transition (EMT). Consistent with these findings, DNRII cells were much less migratory and invasive in vitro and metastatic in vivo than the control cells. Therefore, an intact TGFβ signaling pathway appears necessary for the metastatic phenotypes of this carcinoma model.Keywords: TGFβ, transforming growth factor β, autocrine TGFβ signaling, human endometrial cancer, metastasis, epithelial–mesenchymal transition

Dendritic structure is sensitive to changes in the environment during brain development. Accumulating evidence has demonstrated that early immune activation can significantly affect neuronal development. Our study concentrated on the morphological study of neural dendrites and spines in the hippocampal CA1 area using Diolistic labeling with Sholl analysis and fractal analysis. The results revealed that Bacille Calmette-Guerin (BCG) vaccination enhanced dendritic complexity, as reflected by the increased number of intersections, number of branch points and fractal dimension, and promoted neurite outgrowth. In addition, BCG increased the density and promoted the maturation of dendritic spines. The alterations in dendritic structure and spine morphology were observed at 2 and 4 w, but the differences were more apparent at 4 w than at 2 w. However, no significant difference was observed at 8 w. Furthermore, we observed that BCG increased the expression of hippocampal brain derived neurotrophic factor (BDNF) and insulin-like growth factor 1 (IGF-1). Hippocampal BDNF/IGF-1 was positively correlated with apical dendritic length, fractal dimension, and spine density. Taken together, we show in this study that neonatal BCG vaccination promotes dendritic development in developing hippocampal CA1 neurons, most likely by increasing the expression of BDNF and IGF-1 in the hippocampus.

We previously demonstrated that A(H1N1) influenza vaccine (AIV) promoted hippocampal neurogenesis and working memory in pregnant mice. However, the underlying mechanism of flu vaccination in neurogenesis and memory has remained unclear. In this study, we found that T lymphocytes were recruited from the periphery to the choroid plexus (CP) of the lateral and third (3rd) ventricles in pregnant mice vaccinated with AIV (Pre+AIV). Intracerebroventricular delivery of anti-TCR antibodies markedly decreased neurogenesis and the working memory of the Pre+AIV mice. Similarly, intravenous delivery of anti-CD4 antibodies to the periphery also down-regulated neurogenesis. Furthermore, AIV vaccination caused microglia to skew toward an M2-like phenotype (increased Arginase-1 and Ym1 mRNA levels), and elevated levels of brain-derived growth factor (BDNF) and insulin-like growth factor-1 (IGF-1) were found in the hippocampus, whereas these effects were offset by anti-TCR antibody treatment. Additionally, in the CP, the expression level of adhesion molecules and chemokines, which assist leukocytes in permeating into the brain, were also elevated after AIV vaccination of pregnant mice. Collectively, the results suggested that the infiltrative T lymphocytes in the CP contribute to the increase in hippocampal neurogenesis and working memory caused by flu vaccination, involving activation of the brain’s CP, M2 microglial polarization and neurotrophic factor expression.

The basal forebrain (BF) plays a crucial role in cortical activation. Our previous study showed that activation of cholinergic BF neurons alone is sufficient to suppress slow-wave sleep (SWS) and promote wakefulness and rapid-eye-movement (REM) sleep. However, the exact role of silencing cholinergic BF neurons in the sleep-wake cycle remains unclear. We inhibitied the cholinergic BF neurons genetically targeted with archaerhodopsin (Arch) with yellow light to clarify the role of cholinergic BF neurons in the sleep-wake cycle. Bilateral inactivation of cholinergic BF neurons genetically targeted with archaerhodopsin prolonged SWS and decreased the probability of awakening from SWS in mice. However, silencing these neurons changed neither the duration of wakefulness or REM sleep, nor the probability of transitions to other sleep-wake episodes from wakefulness or REM sleep. Furthermore, silencing these neurons for 6 h within the inactive or active period increased the duration of SWS at the expense of the duration of wakefulness, as well as increasing the number of prolonged SWS episodes (120-240 s). The lost wakefulness was compensated by a delayed increase of wakefulness, so the total duration of SWS and wakefulness during 24 h was kept stable. Our results indicate that the main effect of these neurons is to terminate SWS, whereas wakefulness or REM sleep may be determined by co-operation of the cholinergic BF neurons with other arousal-sleep control systems.

Hypertension is the most common cardiovascular disease, afflicting >30% of adults1. The cause of hypertension in most individuals remains unknown2,3, suggesting that additional contributing factors have yet to be discovered. Corin is a serine protease that activates the natriuretic peptides, thereby regulating blood pressure4. It is synthesized as a zymogen that is activated by proteolytic cleavage. CORIN variants and mutations impairing corin activation have been identified in people with hypertension and pre-eclampsia5–9. To date, however, the identity of the protease that activates corin remains elusive. Here we show that proprotein convertase subtilisin/kexin-6 (PCSK6, also named PACE4; ref. 10) cleaves and activates corin. In cultured cells, we found that corin activation was inhibited by inhibitors of PCSK family proteases and by small interfering RNAs blocking PCSK6 expression. Conversely, PCSK6 overexpression enhanced corin activation. In addition, purified PCSK6 cleaved wild-type corin but not the R801A variant that lacks the conserved activation site. Pcsk6-knockout mice developed salt-sensitive hypertension, and corin activation and pro-atrial natriuretic peptide processing activity were undetectable in these mice. Moreover, we found that CORIN variants in individuals with hypertension and pre-eclampsia were defective in PCSK6-mediated activation. We also identified a PCSK6 mutation that impaired corin activation activity in a hypertensive patient. Our results indicate that PCSK6 is the long-sought corin activator and is important for sodium homeostasis and normal blood pressure.

The interaction between adaptive immune system and the Central Nervous System (CNS) has been extensively studied for decades. A series of researches have indicated that systemic T cells, particularly CD4+ T cells are involved in supporting fundamental processes of brain functional integrity, such as in the maintenance of brain plasticity including spatial learning and memory, and neurogenesis. Moreover, recent data from our laboratory indicate alteration of systemic T helper cell type 1 (Th1)/Th2 balance is tightly linked to hippocampal neurogenesis and working memory. In this review, we summarize current knowledge of the systemic Th1/Th2 balance, describe how this skewing appears to operate in hippocampal neurogenesis, and reinforce the theory of interaction mechanism of these two vital systems.

TGF[beta]1, [beta]2, and [beta]3 are 25 kDa homodimeric polypeptides that play crucial non-overlapping roles in development, tumor suppression, and wound healing. They exhibit 70-82% sequence identity and transduce their signals by binding and bringing together the TGF[beta] type I and type II receptors, T[beta]RI and T[beta]RII. TGF[beta]2 differs from the other isoforms in that it binds T[beta]RII weakly and is dependent upon the co-receptor betaglycan for function. To explore the physicochemical basis underlying these differences, we generated a series of single amino acid T[beta]RII variants based on the crystal structure of the T[beta]RII:TGF[beta]3 complex and examined these in terms of their TGF[beta] isoform binding affinity and their equilibrium stability. The results showed that T[beta]RII Ile53 and Glu119, which contact TGF[beta]3 Val92 and Arg25, respectively, together with T[beta]RII Asp32, Glu55, and Glu75, which contact TGF[beta]3 Arg94, each contribute significantly, between 1 kcal mol-1 to 1.5 kcal mol-1, to ligand binding affinities. These contacts likely underlie the estimated 4.1 kcal mol-1 lower affinity with which T[beta]RII binds TGF[beta]2 as these three ligand residues are unchanged in TGF[beta]1 but are conservatively substituted in TGF[beta]2 (Lys25, Ile92, and Lys94). To test this hypothesis, a TGF[beta]2 variant was generated in which these three residues were changed to those in TGF[beta]s 1 and 3. This variant exhibited receptor binding affinities comparable to those of TGF[beta]s 1 and 3. Together, these results show that these three residues underlie the lowered affinity of TGF[beta]2 for T[beta]RII and that all isoforms likely induce assembly of the TGF[beta] signaling receptors in the same overall manner

Transforming growth factor-beta (TGFbeta) isoforms initiate signaling by assembling a heterotetrameric complex of paired type I (TbetaRI) and type II (TbetaRII) receptors on the cell surface. Because two of the ligand isoforms (TGFbetas 1, 3) must first bind TbetaRII to recruit TbetaRI into the complex, and a third (TGFbeta2) requires a co-receptor, assembly is known to be sequential, cooperative and isoform-dependent. However the source of the cooperativity leading to recruitment of TbetaRI and the universality of the assembly mechanism with respect to isoforms remain unclear. Here, we show that the extracellular domain of TbetaRI (TbetaRI-ED) binds in vitro with high affinity to complexes of the extracellular domain of TbetaRII (TbetaRII-ED) and TGFbetas 1 or 3, but not to either ligand or receptor alone. Thus, recruitment of TbetaRI requires combined interactions with TbetaRII-ED and ligand, but not membrane attachment of the receptors. Cell-based assays show that TbetaRI-ED, like TbetaRII-ED, acts as an antagonist of TGFbeta signaling, indicating that receptor-receptor interaction is sufficient to compete against endogenous, membrane-localized receptors. On the other hand, neither TbetaRII-ED, nor TbetaRII-ED and TbetaRI-ED combined, form a complex with TGFbeta2, showing that receptor-receptor interaction is insufficient to compensate for weak ligand-receptor interaction. However, TbetaRII-ED does bind with high affinity to TGFbeta2-TM, a TGFbeta2 variant substituted at three positions to mimic TGFbetas 1 and 3 at the TbetaRII binding interface. This proves both necessary and sufficient for recruitment of TbetaRI-ED, suggesting that the three different TGFbeta isoforms induce assembly of the heterotetrameric receptor complex in the same general manner.