WITHDRAWN: Gut Microbiota Alter Visceral Pain Sensation and Inflammation via Modulation of Synthesis of Resolvin D1 in Colonic Tuft Cells

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Genome-wide identification and expression analysis of wall-associated kinase (WAK) and WAK-like kinase gene family in response to tomato yellow leaf curl virus infection in Nicotiana benthamiana.

BACKGROUND: Tomato yellow leaf curl virus (TYLCV) is a major monopartite virus in the family Geminiviridae and has caused severe yield losses in tomato and tobacco planting areas worldwide. Wall-associated kinases (WAKs) and WAK-like kinases (WAKLs) are a subfamily of the receptor-like kinase family implicated in cell wall signaling and transmitting extracellular signals to the cytoplasm, thereby regulating plant growth and development and resistance to abiotic and biotic stresses. Recently, many studies on WAK/WAKL family genes have been performed in various plants under different stresses; however, identification and functional survey of the WAK/WAKL gene family of Nicotiana benthamiana have not yet been performed, even though its genome has been sequenced for several years. Therefore, in this study, we aimed to identify the WAK/WAKL gene family in N. benthamiana and explore their possible functions in response to TYLCV infection. RESULTS: Thirty-eight putative WAK/WAKL genes were identified and named according to their locations in N. benthamiana. Phylogenetic analysis showed that NbWAK/WAKLs are clustered into five groups. The protein motifs and gene structure compositions of NbWAK/WAKLs appear to be highly conserved among the phylogenetic groups. Numerous cis-acting elements involved in phytohormone and/or stress responses were detected in the promoter regions of NbWAK/WAKLs. Moreover, gene expression analysis revealed that most of the NbWAK/WAKLs are expressed in at least one of the examined tissues, suggesting their possible roles in regulating the growth and development of plants. Virus-induced gene silencing and quantitative PCR analyses demonstrated that NbWAK/WAKLs are implicated in regulating the response of N. benthamiana to TYLCV, ten of which were dramatically upregulated in locally or systemically infected leaves of N. benthamiana following TYLCV infection. CONCLUSIONS: Our study lays an essential base for the further exploration of the potential functions of NbWAK/WAKLs in plant growth and development and response to viral infections in N. benthamiana.

Upregulation of acid sensing ion channels is associated with esophageal hypersensitivity in GERD.

Proton pump inhibitors (PPIs) are the mainstay of therapy for gastroesophageal reflux disease (GERD) but up to 60% of patients have inadequate response to therapy. Acid sensing ion channels (ASICs) play important roles in nociception. This study aimed to investigate whether the increased expression of ASICs results in neuronal hyperexcitability in GERD. Esophageal biopsies were taken from GERD patients and healthy subjects to compare expression of ASIC1 and 3. Next, gene and protein expression of ASIC1 and 3 from esophageal mucosa and dorsal root ganglia (DRG) neurons were measured by qPCR, Western-blot and immunofluorescence in rodent models of reflux esophagitis (RE), non-erosive reflux disease (NERD), and sham operated groups. Excitability of DRG neurons in the GERD and sham groups were also tested by whole-cell patch-clamp recordings. We demonstrated that ASIC1 and 3 expression were significantly increased in patients with RE compared with healthy controls. This correlated positively with symptom severity of heartburn and regurgitation (p < .001). Next, ASIC1 and 3 gene and protein expression in rodent models of RE and NERD were similarly increased in esophageal mucosa as well as T3-T5 DRG neurons compared with sham operation. DRG neurons from RE animals showed hyperexcitability compared with sham group. However, intrathecal injection of ASIC specific inhibitors, PcTx1 and APTEx-2, as well as silencing ASIC1 and 3 genes with specific siRNAs prevented visceral hypersensitivity. Overall, upregulation of ASIC1 and 3 may lead to visceral hypersensitivity in RE and NERD and may be a potential therapeutic target for PPI non-responsive patients.

Prostaglandin E2, Produced by Mast Cells in Colon Tissues From Patients With Irritable Bowel Syndrome, Contributes to Visceral Hypersensitivity in Mice.

BACKGROUND AND AIMS: Visceral hypersensitivity is common in patients with irritable bowel syndrome (IBS). We investigated whether inflammatory molecules, such as histamine and proteases, activate prostaglandin-endoperoxide synthase 2 (also called COX2) to increase the synthesis of prostaglandin E2 (PGE2) by mast cells, which activates the receptor PTGER2 (also called EP2) in the dorsal root ganglia to promote visceral hypersensitivity. METHODS: We used an enzyme-linked immunosorbent assay to measure levels of spontaneous release of molecules from mast cells in colonic mucosa from patients with IBS with diarrhea (IBS-D; 18 women and 5 men; aged 28-60 years), healthy individuals (controls, n = 24), mice, and rats. We measured visceromotor responses to colorectal distension in rodents after intracolonic administration of colon biopsy supernatants, histamine, PGE2, a small interfering RNA against EP2, or an agonist of F2R like trypsin receptor 1 (F2RL1, also called protease-activated receptor 2 [PAR2]). We investigated the role of COX2, produced by mast cells, in mediation of visceral hypersensitivity using mice with the Y385F substitution in Ptgs2 (Ptgs2Y385F mice), mast cell-deficient (W/WV) mice, and W/WV mice given injections of mast cells derived from wild-type or Ptgs2Y385F mice. RESULTS: Colon biopsies from patients with IBS-D had increased levels of PGE2, based on enzyme-linked immunosorbent assay, and COX2 messenger RNA and protein, compared with control biopsies. Immunohistochemistry showed that most of the COX2 was in mast cells. Intracolonic infusions of rats with IBS-D biopsy supernatants generated a 3- to 4-fold increase in visceromotor responses to colorectal distension; this was associated with significant increases in PGE2, histamine, and tryptase in the colonic mucosa. These increases were prevented by a mast cell stabilizer, COX2 inhibitor, or knockdown of EP2. Intracolonic administration of supernatants from biopsies of patients with IBS-D failed to induce visceral hypersensitivity or increase the level of PGE2 in W/WV and Ptgs2Y385Fmice. Reconstitution of mast cells in W/WV mice restored the visceral hypersensitivity response. CONCLUSIONS: Abnormal synthesis of PGE2 by colonic mast cells appears to induce visceral hypersensitivity in patients with IBS-D.

Altered R-spondin 1/CART neurocircuit in the hypothalamus contributes to hyperphagia in diabetes.

Hyperphagia is common in diabetes and may worsen hyperglycemia and diabetic complications. The responsible mechanisms are not well understood. The hypothalamus is a key center for the control of appetite and energy homeostasis. The ventromedial nucleus (VMH) and arcuate nucleus (ARC) are two critical nuclei involved in these processes. We have reported that R-spondin 1 (Rspo1) and its receptor leucin-rich repeat and G protein-coupled receptor 4 (LGR4) in the VMH and ARC suppressed appetite, but the downstream neuronal pathways are unclear. Here we show that neurons containing cocaine and amphetamine-regulated transcript (CART) in ARC express both LGR4 and insulin receptor; intracerebroventricular injection of Rspo1 induced c-Fos expression in CART neurons of ARC; and silencing CART in ARC attenuated the anorexigenic actions of Rspo1. In diabetic and obese fa/fa rats, Rspo1 mRNA in VMH and CART mRNA in ARC were reduced; this was accompanied by increased food consumption. Insulin treatment restored Rspo1 and CART gene expressions and normalized eating behavior. Chronic intracerebroventricular injection of Rspo1 inhibited food intake and normalized diabetic hyperphagia; intracerebroventricular injection of Rspo1 or insulin increased CART mRNA in ARC. In the CART neuron cell line, Rspo1 and insulin potentiated each other on pERK and ß-catenin, and in rats, they acted synergistically to inhibit food intake. Silencing Rspo1 in VMH reduced CART expression in ARC and attenuated the inhibitory effect of insulin on food intake. In conclusion, our data indicated that CART works downstream of Rspo1 and Rspo1 mediated the action of insulin centrally. The altered Rspo1/CART neurocircuit in the hypothalamus contributes to hyperphagia in diabetes. NEW & NOTEWORTHY This study reports that cocaine and amphetamine-regulated transcript (CART) neurons in the arcuate nucleus (ARC) of hypothalamus acted downstream of R-spondin 1 (Rspo1) to inhibit food intake. The Rspo1 mRNA level in ventromedial nucleus (VMH) and CART mRNA level in ARC were reduced in type 1 diabetic rat and obese fa/fa rat. Rspo1 and insulin acted synergistically on phospho-ERK and ß-catenin signal pathways and in suppressing food intake. The current results proposed that altered Rspo1/CART neurocircuit in the hypothalamus contributes to hyperphagia in diabetes.

Increased Activation of the TRESK K+ Mediates Vago-Vagal Reflex Malfunction in Diabetic Rats.

BACKGROUND & AIMS: Patients with diabetes have defects in the vagal afferent pathway that result in abnormal gastrointestinal function. We investigated whether selective increased activation of the 2-pore domain potassium channel TRESK (2-pore-domain weak inward-rectifying potassium channel-related spinal cord potassium channel) contributes to nodose ganglia (NG) malfunction, disrupting gastrointestinal function in diabetic rats. METHODS: We conducted whole-cell current-clamp and single-unit recordings in NG neurons from diabetes-prone BioBreeding/Worcester rats and streptozotocin-induced diabetic (STZ-D) rats and compared them with control rats. NG neurons in rats or cultured NG neurons were exposed to pharmacologic antagonists and/or transfected with short hairpin or small interfering RNAs that reduced expression of TRESK. We then made electrophysiologic recordings and studied gastrointestinal functions. RESULTS: We observed reduced input resistance, hyperpolarized membrane potential, and increased current threshold to elicit action potentiation in NG neurons of STZ-D rats compared with controls. NG neuron excitability was similarly altered in diabetes-prone rats. In vivo single-unit NG neuronal discharges in response to 30 and 60 pmol cholecystokinin octapeptide were significantly lower in STZ-D rats compared with controls. Reducing expression of the TRESK K+ channel restored NG excitability in vitro and in vivo, as well as cholecystokinin 8-stimulated secretion of pancreatic enzymes and secretin-induced gastrointestinal motility, which are mediated by vago-vagal reflexes. These abnormalities resulted from increased intracellular Ca2+ in the NG, activating calcineurin, which, in turn, bound to an nuclear factor of activated T cell-like docking site on the TRESK protein, resulting in neuronal membrane hyperpolarization. CONCLUSIONS: In 2 rate models of diabetes, we found that activation of the TRESK K+ channel reduced NG excitability and disrupted gastrointestinal functions.

The association between ambient inhalable particulate matter and the disease burden of respiratory disease: An ecological study based on ten-year time series data in Tianjin, China.

There is limited evidence available worldwide about the quantitative relationship between particulate matter with an aerodynamic diameter of less than 10µm (PM10) and years of life lost (YLL) caused by respiratory diseases (RD), especially regarding long-term time series data. We investigated the quantitative exposure-response association between PM10 and the disease burden of RD. We obtained the daily concentration of ambient pollutants (PM10, nitrogen dioxide and sulphur dioxide), temperature and relative humidity data, as well as the death monitoring data from 2001 to 2010 in Tianjin. Then, a time series database was built after the daily YLL of RD was calculated. We applied a generalized additive model (GAM) to estimate the burden of PM10 on daily YLL of RD and to determine the effect (the increase of daily YLL) of every 10µg/m3 increase in PM10 on health. We found that every 10µg/m3 increase in PM10 was associated with the greatest increase in YLL of 0.84 (95% CI: 0.45, 1.23) years at a 2-day (current day and previous day, lag01) moving average PM10 concentration for RD. The association between PM10 and YLL was stronger in females and the elderly (≥65 years of age). The association between PM10 and YLL of RD differed according to district. These findings also provide new epidemiological evidence for respiratory disease prevention.

KATP channels in the nodose ganglia mediate the orexigenic actions of ghrelin.

Ghrelin, a hunger signalling peptide derived from the peripheral tissues, overcomes the satiety signals evoked by anorexigenic molecules, such as cholecystokinin (CCK) and leptin, to stimulate feeding. Using in vivo and in vitro electrophysiological techniques, we show that ghrelin hyperpolarizes neurons and inhibits currents evoked by leptin and CCK-8. Administering a KATP channel antagonist or silencing Kir6.2, a major subunit of the KATP channel, abolished ghrelin inhibition. The inhibitory actions of ghrelin were also abolished by treating the vagal ganglia neurons with pertussis toxin, as well as phosphatidylinositol 3-kinase (PI3K) or extracellular signal-regulated kinase 1 and 2 (Erk1/2) small interfering RNA. Feeding experiments showed that silencing Kir6.2 in the vagal ganglia abolished the orexigenic actions of ghrelin. These data indicate that ghrelin modulates vagal ganglia neuron excitability by activating KATP conductance via the growth hormone secretagogue receptor subtype 1a-Gαi -PI3K-Erk1/2-KATP pathway. This provides a mechanism to explain the actions of ghrelin with respect to overcoming anorexigenic signals that act via the vagal afferent pathways. Ghrelin is the only known hunger signal derived from the peripheral tissues. Ghrelin overcomes the satiety signals evoked by anorexigenic molecules, such as cholecystokinin (CCK) and leptin, to stimulate feeding. The mechanisms by which ghrelin reduces the sensory signals evoked by anorexigenic hormones, which act via the vagus nerve to stimulate feeding, are unknown. Patch clamp recordings of isolated rat vagal neurons show that ghrelin hyperpolarizes neurons by activating K(+) conductance. Administering a KATP channel antagonist or silencing Kir6.2, a major subunit of the KATP channel, abolished ghrelin inhibition in vitro and in vivo. Patch clamp studies show that ghrelin inhibits currents evoked by leptin and CCK-8, which operate through independent ionic channels. The inhibitory actions of ghrelin were abolished by treating the vagal ganglia neurons with pertussis toxin, as well as phosphatidylinositol 3-kinase (PI3K) or extracellular signal-regulated kinase 1 and 2 (Erk1/2) small interfering RNA. In vivo gene silencing of PI3K and Erk1/2 in the nodose ganglia prevented ghrelin inhibition of leptin- or CCK-8-evoked vagal firing. Feeding experiments showed that silencing Kir6.2 in the vagal ganglia abolished the orexigenic actions of ghrelin. These data indicate that ghrelin modulates vagal ganglia neuron excitability by activating KATP conductance via the growth hormone secretagogue receptor subtype 1a-Gαi -PI3K-Erk1/2-KATP pathway. The resulting hyperpolarization renders the neurons less responsive to signals evoked by anorexigenic hormones. This provides a mechanism to explain the actions of ghrelin with respect to overcoming anorexigenic signals that act via the vagal afferent pathways.

Rifaximin alters intestinal bacteria and prevents stress-induced gut inflammation and visceral hyperalgesia in rats.

BACKGROUND & AIMS: Rifaximin is used to treat patients with functional gastrointestinal disorders, but little is known about its therapeutic mechanism. We propose that rifaximin modulates the ileal bacterial community, reduces subclinical inflammation of the intestinal mucosa, and improves gut barrier function to reduce visceral hypersensitivity. METHODS: We induced visceral hyperalgesia in rats, via chronic water avoidance or repeat restraint stressors, and investigated whether rifaximin altered the gut microbiota, prevented intestinal inflammation, and improved gut barrier function. Quantitative polymerase chain reaction (PCR) and 454 pyrosequencing were used to analyze bacterial 16S ribosomal RNA in ileal contents from the rats. Reverse transcription, immunoblot, and histologic analyses were used to evaluate levels of cytokines, the tight junction protein occludin, and mucosal inflammation, respectively. Intestinal permeability and rectal sensitivity were measured. RESULTS: Water avoidance and repeat restraint stress each led to visceral hyperalgesia, accompanied by mucosal inflammation and impaired mucosal barrier function. Oral rifaximin altered the composition of bacterial communities in the ileum (Lactobacillus species became the most abundant) and prevented mucosal inflammation, impairment to intestinal barrier function, and visceral hyperalgesia in response to chronic stress. Neomycin also changed the composition of the ileal bacterial community (Proteobacteria became the most abundant species). Neomycin did not prevent intestinal inflammation or induction of visceral hyperalgesia induced by water avoidance stress. CONCLUSIONS: Rifaximin alters the bacterial population in the ileum of rats, leading to a relative abundance of Lactobacillus. These changes prevent intestinal abnormalities and visceral hyperalgesia in response to chronic psychological stress.

Butyrate-induced colonic hypersensitivity is mediated by mitogen-activated protein kinase activation in rat dorsal root ganglia.

OBJECTIVE: Increased faecal butyrate levels have been reported in irritable bowel syndrome. Rectal instillation of sodium butyrate (NaB) increases visceral sensitivity in rats by an unknown mechanism. We seek to examine the signal transduction pathways responsible for the enhanced neuronal excitability in the dorsal root ganglion (DRG) following NaB enemas and demonstrate that this is responsible for the colonic hypersensitivity reported in this animal model. DESIGN: Colorectal distention (CRD) studies were performed in rats treated with NaB rectal instillation with/without intrathecal or intravenous administration of mitogen-activated protein (MAP) kinase kinase inhibitor U0126. Western blot analysis and immunocytochemistry studies elucidated intracellular signalling pathways that modulate IA. Patch-clamp recordings were performed on isolated DRG neurons treated with NaB, with/without U0126. RESULTS: Visceromotor responses (VMR) were markedly enhanced in NaB-treated rats. Western blot analysis of DRG neurons from NaB-treated rats showed a 2.2-fold increase in phosphorylated ERK1/2 (pEKR1/2) and 1.9-fold increase in phosphorylated voltage-gated potassium channel subunit 4.2 (pKv4.2). Intrathecal or intravenous administration of U0126 reduced VMR to CRD in NaB-treated rats and prevented increases in pERK1/2 and pKv4.2. Patch-clamp recordings of isolated DRG neurons showed that NaB caused a reduction in IA to 48.9%±1.4% of control and an increase in neuronal excitability, accompanied by a twofold increase in pERK1/2 and pKv4.2. Concurrent U0126 administration prevented these changes. CONCLUSIONS: Visceral hypersensitivity induced by colonic NaB treatment is mediated by activation of the MAP kinase-ERK1/2 pathway, which phosphorylates Kv4.2. This results in a reduction in IA and an enhancement of DRG neuronal excitability.

Prediction of half-marathon performance of male recreational marathon runners using nomogram.

BACKGROUND: Long-distance running is a popular competitive sport. We performed the current research as to develop an easily accessible and applicable model to predict half-marathon performance in male recreational half-marathon runners by nomogram. METHODS: Male recreational half-marathon runners in Zhejiang Province, China were recruited. A set of literature-based and panel-reviewed questionnaires were used to assess the epidemiological conditions of the recruited runners. Descriptive and binary regression analyses were done for the profiling and identification of predictors related to higher half-marathon performance (completing time ≤ 105 min). Participants were assigned to the training set (n = 141) and the testing set (n = 61) randomly. A nomogram was used to visually predict the half-marathon performance, and the receiver operating characteristic (ROC) was used to evaluate the predictive ability of the nomogram. RESULTS: A total of 202 participants (median age: 49 years; higher half-marathon performance: 33.7%) were included. After multivariate analysis, three variables remained as significant predictors: longer monthly running distance [adjusted odds ratio (AOR) = 0.992, 95% confidence interval (CI): 0.988 to 0.996, p < 0.001], faster mean training pace (AOR = 2.151, 95% CI: 1.275 to 3.630, p < 0.001), and better sleep quality [the Pittsburgh Sleep Quality Index (PSQI), AOR = 2.390, 95% CI: 1.164 to 4.907, p = 0.018]. The AUC of the training and testing sets in nomogram were 0.750 and 0.743, respectively. Further ternary and linear regression analyses corroborated the primary findings. CONCLUSIONS: This study developed a nomogram with good potential to predict the half-marathon performance of recreational runners. Our results suggest that longer monthly running distance, faster mean training pace and better sleep quality notably contribute to better half-marathon performance.

Role of prostaglandin D2 in mast cell activation-induced sensitization of esophageal vagal afferents.

Sensitization of esophageal afferents plays an important role in esophageal nociception, but the mechanism is less clear. Our previous studies demonstrated that mast cell (MC) activation releases the preformed mediators histamine and tryptase, which play important roles in sensitization of esophageal vagal nociceptive C fibers. PGD2 is a lipid mediator released by activated MCs. Whether PGD2 plays a role in this sensitization process has yet to be determined. Expression of the PGD2 DP1 and DP2 receptors in nodose ganglion neurons was determined by immunofluorescence staining, Western blotting, and RT-PCR. Extracellular recordings were performed in ex vivo esophageal-vagal preparations. Action potentials evoked by esophageal distension were compared before and after perfusion of PGD2, DP1 and DP2 receptor agonists, and MC activation, with or without pretreatment with antagonists. The effect of PGD2 on 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI)-labeled esophageal nodose neurons was determined by patch-clamp recording. Our results demonstrate that DP1 and DP2 receptor mRNA and protein were expressed mainly in small- and medium-diameter neurons in nodose ganglia. PGD2 significantly increased esophageal distension-evoked action potential discharges in esophageal nodose C fibers. The DP1 receptor agonist BW 245C mimicked this effect. PGD2 directly sensitized DiI-labeled esophageal nodose neurons by decreasing the action potential threshold. Pretreatment with the DP1 receptor antagonist BW A868C significantly inhibited PGD2 perfusion- or MC activation-induced increases in esophageal distension-evoked action potential discharges in esophageal nodose C fibers. In conclusion, PGD2 plays an important role in MC activation-induced sensitization of esophageal nodose C fibers. This adds a novel mechanism of visceral afferent sensitization.

Resting-state coupling between HbO and Hb measured by fNIRS in autism spectrum disorder.

To distinguish between children with autism spectrum disorder (ASD) and typically developing (TD) children, we have uncovered a new discriminative feature, hemoglobin coupling. Functional near-infrared spectroscopy (fNIRS) was used to record resting-state hemodynamic fluctuations in the bilateral temporal lobes in 25 children with ASD and 22 TD children, in which the coupling between low frequency oxygenated hemoglobin (HbO) and deoxygenated hemoglobin (Hb) fluctuations was evaluated by Pearson correlation coefficient. The results showed significantly weak coupling in children with ASD in both the left and right, and throughout the whole temporal cortex. To explain this observation, a simulation study was performed using a balloon model, in which we found four related parameters could impact the coupling. This study suggested that hemoglobin coupling might be applied as a new cerebral hemodynamic characteristic for ASD screening or diagnostics.

Normalized mutual information of fNIRS signals as a measure for accessing typical and atypical brain activity.

Normalized mutual information (NMI) can be used to detect statistical correlations between time series. We showed possibility of using NMI to quantify synchronicity of information transmission in different brain regions, thus to characterize functional connections, and ultimately analyze differences in physiological states of brain. Resting-state brain signals were recorded from bilateral temporal lobes by functional near-infrared spectroscopy (fNIRS) in 19 young healthy (YH) adults, 25 children with autism spectrum disorder (ASD), and 22 children with typical development (TD). Using NMI of the fNIRS signals, common information volume was assessed for each of three groups. Results showed that mutual information of children with ASD was significantly smaller than that of TD children, while mutual information of YH adults was slightly larger than that of TD children. This study may suggest that NMI could be a measure for assessing brain activity with different development states.

Identification and Molecular Characterization of a Novel Carlavirus Infecting Chrysanthemum morifolium in China.

Chrysanthemum (Chrysanthemum morifolium) is an important ornamental and medicinal plant suffering from many viruses and viroids worldwide. In this study, a new carlavirus, tentatively named Chinese isolate of Carya illinoinensis carlavirus 1 (CiCV1-CN), was identified from chrysanthemum plants in Zhejiang Province, China. The genome sequence of CiCV1-CN was 8795 nucleotides (nt) in length, with a 68-nt 5'-untranslated region (UTR) and a 76-nt 3'-UTR, which contained six predicted open reading frames (ORFs) that encode six corresponding proteins of various sizes. Phylogenetic analyses based on full-length genome and coat protein sequences revealed that CiCV1-CN is in an evolutionary branch with chrysanthemum virus R (CVR) in the Carlavirus genus. Pairwise sequence identity analysis showed that, except for CiCV1, CiCV1-CN has the highest whole-genome sequence identity of 71.3% to CVR-X6. At the amino acid level, the highest identities of predicted proteins encoded by the ORF1, ORF2, ORF3, ORF4, ORF5, and ORF6 of CiCV1-CN were 77.1% in the CVR-X21 ORF1, 80.3% in the CVR-X13 ORF2, 74.8% in the CVR-X21 ORF3, 60.9% in the CVR-BJ ORF4, 90.2% in the CVR-X6 and CVR-TX ORF5s, and 79.4% in the CVR-X21 ORF6. Furthermore, we also found a transient expression of the cysteine-rich protein (CRP) encoded by the ORF6 of CiCV1-CN in Nicotiana benthamiana plants using a potato virus X-based vector, which can result in a downward leaf curl and hypersensitive cell death over the time course. These results demonstrated that CiCV1-CN is a pathogenic virus and C. morifolium is a natural host of CiCV1.

Integrated comparative transcriptome and weighted gene co-expression network analysis provide valuable insights into the response mechanisms of crayfish (Procambarus clarkii) to copper stress.

One of the significant limitations of aquaculture worldwide is the prevalence of divalent copper (Cu). Crayfish (Procambarus clarkii) are economically important freshwater species adapted to a variety of environmental stimuli, including heavy metal stresses; however, large-scale transcriptomic data of the hepatopancreas of crayfish in response to Cu stress are still scarce. Here, integrated comparative transcriptome and weighted gene co-expression network analyses were initially applied to investigate gene expression profiles of the hepatopancreas of crayfish subjected to Cu stress for different periods. As a result, 4662 significant differentially expressed genes (DEGs) were identified following Cu stress. Bioinformatics analyses revealed that the "focal adhesion" pathway was one of the most significantly upregulated response pathways following Cu stress, and seven DEGs mapped to this pathway were identified as hub genes. Furthermore, the seven hub genes were examined by quantitative PCR, and each was found to have a substantial increase in transcript abundance, suggesting a critical role of the "focal adhesion" pathway in the response of crayfish to Cu stress. Our transcriptomic data can be a good resource for the functional transcriptomics of crayfish, and these results may provide valuable insights into the molecular response mechanisms underlying crayfish to Cu stress.

Cocaine- and amphetamine-regulated transcript is the neurotransmitter regulating the action of cholecystokinin and leptin on short-term satiety in rats.

Vagal CCK-A receptors (CCKARs) and leptin receptors (LRbs) interact synergistically to mediate short-term satiety. Cocaine- and amphetamine-regulated transcript (CART) peptide is expressed by vagal afferent neurons. We sought to demonstrate that this neurotransmitter regulates CCK and leptin actions on short-term satiety. We also examined the signal transduction pathways responsible for mediating the CART release from the nodose ganglia (NG). ELISA studies coupled with gene silencing of NG neurons by RNA interference elucidated intracellular signaling pathways responsible for CCK/leptin-stimulated CART release. Feeding studies followed by gene silencing of CART in NG established the role of CART in mediating short-term satiety. Immunohistochemistry was performed on rat NG neurons to confirm colocalization of CCKARs and LRbs; 63% of these neurons contained CART. Coadministration of CCK-8 and leptin caused a 2.2-fold increase in CART release that was inhibited by CCK-OPE, a low-affinity CCKAR antagonist. Transfection of cultured NG neurons with steroid receptor coactivator (SRC) or phosphatidylinositol 3-kinase (PI3K) small-interfering RNA (siRNA) or STAT3 lentiviral short hairpin RNA inhibited CCK/leptin-stimulated CART release. Silencing the expression of the EGR-1 gene inhibited the CCK/leptin-stimulated CART release but had no effect on CCK/leptin-stimulated neuronal firing. Electroporation of NG with CART siRNA inhibited CCK/leptin stimulated c-Fos expression in rat hypothalamus. Feeding studies following electroporation of the NG with CART or STAT3 siRNA abolished the effects of CCK/leptin on short-term satiety. We conclude that the synergistic interaction of low-affinity vagal CCKARs and LRbs mediates CART release from the NG, and CART is the principal neurotransmitter mediating short-term satiety. CART release from the NG involves interaction between CCK/SRC/PI3K cascades and leptin/JAK2/PI3K/STAT3 signaling pathways.

Corticosterone mediates reciprocal changes in CB 1 and TRPV1 receptors in primary sensory neurons in the chronically stressed rat.

BACKGROUND & AIMS: Chronic stress is associated with visceral hyperalgesia in functional gastrointestinal disorders. We investigated whether corticosterone plays a role in chronic psychological stress-induced visceral hyperalgesia. METHODS: Male rats were subjected to 1-hour water avoidance (WA) stress or subcutaneous corticosterone injection daily for 10 consecutive days in the presence or absence of corticoid-receptor antagonist RU-486 and cannabinoid-receptor agonist WIN55,212-2. The visceromotor response to colorectal distension was measured. Receptor protein levels were measured and whole-cell patch-clamp recordings were used to assess transient receptor potential vanilloid type 1 (TRPV1) currents in L6-S2 dorsal root ganglion (DRG) neurons. Mass spectrometry was used to measure endocannabinoid anandamide content. RESULTS: Chronic WA stress was associated with visceral hyperalgesia in response to colorectal distension, increased stool output and reciprocal changes in cannabinoid receptor 1 (CB1) (decreased) and TRPV1 (increased) receptor expression and function. Treatment of WA stressed rats with RU-486 prevented these changes. Control rats treated with serial injections of corticosterone in situ showed a significant increase in serum corticosterone associated with visceral hyperalgesia, enhanced anandamide content, increased TRPV1, and decreased CB1 receptor protein levels, which were prevented by co-treatment with RU-486. Exposure of isolated control L6-S2 DRGs in vitro to corticosterone reproduced the changes in CB1 and TRPV1 receptors observed in situ, which was prevented by co-treatment with RU-486 or WIN55,212-2. CONCLUSIONS: These results support a novel role for corticosterone to modulate CB1 and TRPV1-receptor pathways in L6-S2 DRGs in the chronic WA stressed rat, which contributes to visceral hyperalgesia observed in this model.