ALS/FTD-Linked Mutation in FUS Suppresses Intra-axonal Protein Synthesis and Drives Disease Without Nuclear Loss-of-Function of FUS

Through the generation of humanized FUS mice expressing full-length human FUS, we identify that when expressed at near endogenous murine FUS levels, both wild-type and ALS-causing and frontotemporal dementia (FTD)-causing mutations complement the essential function(s) of murine FUS. Replacement of murine FUS with mutant, but not wild-type, human FUS causes stress-mediated induction of chaperones, decreased expression of ion channels and transporters essential for synaptic function, and reduced synaptic activity without loss of nuclear FUS or its cytoplasmic aggregation. Most strikingly, accumulation of mutant human FUS is shown to activate an integrated stress response and to inhibit local, intra-axonal protein synthesis in hippocampal neurons and sciatic nerves. Collectively, our evidence demonstrates that human ALS/FTD-linked mutations in FUS induce a gain of toxicity that includes stress-mediated suppression in intra-axonal translation, synaptic dysfunction, and progressive age-dependent motor and cognitive disease without cytoplasmic aggregation, altered nuclear localization, or aberrant splicing of FUS-bound pre-mRNAs. VIDEO ABSTRACT.

Ethyl acetate extract and its major constituent, isorhamnetin 3-O-rutinoside, from Nitraria retusa leaves, promote apoptosis of human myelogenous erythroleukaemia cells

OBJECTIVE

Fractionation of ethyl acetate extract (EA) obtained from Nitraria retusa leaves was assessed using different methods of chromatography, and isorhamnetin3-O-rutinoside (I3-O-R) was isolated from this extract. Its structure was determined using data obtained from (1) H and (13) C NMR spectra, as well as by various correlation experiments (COSY, HMQC and HMBC). Both EA extract and I3-O-R were investigated for their ability to induce apoptosis in human chronic myelogenous erythroleukaemia cells (K562).

MATERIALS AND METHODS

Apoptosis of cells from the K562 line was detected by DNA fragmentation, PARP cleavage and by evaluating activities of caspases 3 and 8.

RESULTS

Apoptosis, revealed by DNA fragmentation and PARP cleavage, was observed after 48-h incubation of these human myelogenous erythroleukaemia cells (K562), with the tested products. Likewise, caspase 3 and caspase 8 activities were induced in the presence of the EA extract and I3-O-R after 48 h of incubation.

CONCLUSION

Our results strongly suggest the involvement of the extrinsic pathway of apoptosis in cells treated by both the original EA extract and its major component, I3-O-R.

Correlation between levels of C-reactive protein and clinical activity in Crohn's disease

AIMS

To determine the factors associated with an increased C-reactive protein level in Crohn's disease patients and to seek a correlation between the C-reactive protein value and the Crohn's disease activity index.

METHODS

We prospectively studied 103 Crohn's disease patients, 76% of whose disease was active at the time of inclusion. C-reactive protein measurement was carried out on all patients. An increased C-reactive protein level was defined as >/=10mg/L.

RESULTS

The median C-reactive protein rate was 53.9mg/L (ranging from 1 to 228mg/L). An increased C-reactive protein was found in 77 patients (75%). By univariate analysis, ileocolic localization, severity of the flare, erythrocyte sedimentation rate, leukocyte and platelet count, fibrinogen, albumin, serum calcium and Crohn's disease activity index were found to be associated to elevated C-reactive protein values. By multivariate analysis, independent factors associated with an increased C-reactive protein level were: ileocolic localization (p=0.02; OR [95% CI]: 2.84 [1.25-9.52]) and moderate or severe disease activity (p=0.001; OR [95% CI]: 4.20 [1.92-8.64]). A statistically significant association between the Crohn's disease activity index score and the C-reactive protein level was found in our study (r=0.302; p=0.001). The optimal C-reactive protein threshold value that separates patients with moderate to severe disease (Crohn's disease activity index>220) from the others was calculated to be 19mg/L with a sensitivity of 76.4% and a specificity of 56.2%.

CONCLUSION

The C-reactive protein level is correlated to disease activity in Crohn's disease. Its role seems to be essential in predicting moderate and severe disease activity.

Antigenotoxic and antioxidant activities of Pituranthos chloranthus essential oils

The SOS-chromotest in Escherichia coli is a widely used bacterial genotoxicity assay to test potential carcinogens. The aim of this work is to evaluate the genotoxic and antigenotoxic activities of essential oils obtained from aerial parts of Pituranthos chloranthus. The tested essential oils were not genotoxic towards both E. coli PQ37 and PQ35 strains. These essential oils reduced significantly Nifuroxazide and H(2)O(2)-induced genotoxicity. Essential oils showed a protective effect against damages induced by radicals, obtained from the photolysis of H(2)O(2), on DNA plasmid through free radical scavenging mechanisms. The scavenging capacity of these essential oils was also estimated by evaluating the inhibition of ABTS(+.) radical.

Antimutagenic, antigenotoxic and antioxidant activities of phenolic-enriched extracts from Teucrium ramosissimum: combination with their phytochemical composition

The evaluation of the mutagenic and antimutagenic actions of extracts obtained from aerial part of Teucrium ramosissimum was assayed using the Salmonella typhimurium assay system. The effect of the same extracts on genotoxicity and SOS response induced by aflatoxin B(1) as well as nitrofurantoin was investigated in a bacterial assay system, i.e., the SOS chromotest with Escherichia coli PQ37. The different extracts showed no mutagenicity when tested with Salmonella typhimurium strains TA100, TA98 and TA1535 either with or without S9 mix. In contrast, our results prove that T. ramosissimum extracts possess antimutagenic effects against sodium azide, aflatoxin B1, benzo[a]pyrene and 4-nitro-o-phenylenediamine. Moreover, the T. ramosissimum tested extracts exhibited no genotoxicity either with or without the external S9 activation mixtures. However, all the extracts significantly decreased the genotoxicity induced by aflatoxin B(1) and nitrofurantoin. The result obtained by the Ames test confirms those of SOS chromotest. Antioxidant capacity of the tested extracts was evaluated using the enzymatic (xanthine/xanthine oxidase assay) and the non enzymatic (NBT/riboflavine, DPPH and ABTS assays) systems. All extracts exhibited high antioxidant activity except the chloroform and the methanol extracts in DPPH and NBT/riboflavine assays respectively. Our results underline the potential of T. ramosissimum to avoid mutations and also its antioxidant potential.

Exploring the effect of sequence length and composition on allele-selective inhibition of human huntingtin expression by single-stranded silencing RNAs

Mutant huntingtin (HTT) protein is the cause of Huntington's disease (HD), an incurable neurological disorder. Almost all patients are heterozygous for mutant HTT and approaches that reduce levels of mutant HTT while leaving expression of wild-type HTT intact might be ideal options for therapeutic development. We have developed several allele-selective strategies for silencing HTT, including single-stranded silencing RNAs (ss-siRNAs). ss-siRNAs are oligonucleotides containing chemical modifications that permit action through the RNA interference (RNAi) pathway. Modified ss-siRNAs chosen to test the effects of varying oligomer length, lipid modification, the introduction of mismatched bases, and variation of chemical modification. We find that several modified ss-siRNA are potent and allele-selective inhibitors of HTT expression. An ss-siRNA with three mismatched bases relative to the CAG repeat was an allele-selective inhibitor of HTT expression in the HdhQ175 mouse model. Multiple allele-selective ss-siRNAs provide a wide platform of modifications to draw on for further optimization and therapeutic development. Our data provide insights into how ss-siRNAs can be modified to improve their properties and facilitate the discovery of the lead compounds necessary for further development.

Assessment of phenolic content, free-radical-scavenging capacity genotoxic and anti-genotoxic effect of aqueous extract prepared from Moricandia arvensis leaves

The present study was undertaken to provide a set of data on the safety of an aqueous extract (AQE) from Moricandia arvensis. For this reason, Escherichia coli tested strains PQ35 and PQ37 were used to detect induction of DNA lesions by AQE. The SOS Chromotest showed that AQE induced a marginally genotoxic effect, as expressed by the induction factor (IF) value only with E. coli PQ37 tested strain (IF=1.77 at a dose of 250 microg/assay). The measurement of the anti-genotoxic activity of the AQE was also studied by inhibition of beta-galactosidase induction. A significant anti-genotoxic effect was observed with different tested doses of AQE, which suggests that M. arvensis extract has the potential to protect DNA from the action of nitrofurantoïn (NF) and free radicals generated by hydrogen peroxide (H2O2). In addition to anti-genotoxic activity, AQE showed a free-radical-scavenging capacity towards ABTS+* and DPPH*. Total phenolic content was also evaluated following Folin-Ciocalteu method and results indicated high correlation between total phenol content and anti-genotoxic and antioxidant activities for AQE, but the highest correlation was showed with its capacity to stabilize ABTS+* (R2=0.9944).

Brain processing of duodenal and portal glucose sensing

Peripheral and central glucose sensing play a major role in the regulation of food intake. Peripheral sensing occurs at duodenal and portal levels, although the importance of these sensing sites is still controversial. The present study aimed to compare the respective influence of these sensing pathways on the eating patterns; plasma concentrations of glucose, insulin and glucagon-like peptide-1 (GLP-1); and brain activity in juvenile pigs. In Experiment 1, we characterised the changes in the microstructure as a result of a 30-min meal in eight conscious animals after duodenal or portal glucose infusion in comparison with saline infusion. In Experiment 2, glucose, insulin and GLP-1 plasma concentrations were measured during 2 h after duodenal or portal glucose infusions in four anaesthetised animals. In Experiment 3, single photon emission computed tomography brain imaging was performed in five anaesthetised animals receiving duodenal or portal glucose or saline infusions. Both duodenal and portal glucose decreased the amount of food consumed, as well as the ingestion speed, although this effect appeared earlier with the portal infusion. Significant differences of glucose and GLP-1 plasma concentrations between treatments were found at the moment of brain imaging. Both duodenal and portal glucose infusions activated the dorsolateral prefrontal cortex and primary somatosensory cortex. Only duodenal glucose infusion was able to induce activation of the prepyriform area, orbitofrontal cortex, caudate and putamen, as well as deactivation of the anterior prefrontal cortex and anterior entorhinal cortex, whereas only portal glucose infusion induced a significant activation of the insular cortex. We demonstrated that duodenal and portal glucose infusions led to the modulation of brain areas that are known to regulate eating behaviour, which probably explains the decrease of food intake after both stimulations. These stimulation pathways induced specific systemic and central responses, suggesting that different brain processing matrices are involved.

Metabolic syndrome is associated with gastroesophageal reflux disease based on a 24-hour ambulatory pH monitoring

Several studies have focused on the relationship between metabolic syndrome and gastroesophageal reflux disease (GERD). They were based on GERD complications, whereas little is known about the association between metabolic syndrome and objectively measured esophageal acid exposure. The aim of our study was to assess the relationship between metabolic syndrome and GERD based on a 24-hour pH testing. It was a cross-sectional study including 100 consecutive patients who underwent a 24-hour pH-metry monitoring and were assessed for the five metabolic syndrome components as well as for body mass index (BMI). Among the 100 patients, 54 had a pathological acid GERD. The 46 GERD-free patients represented control group. Sex distribution was comparable between both groups but GERD patients were older than controls (44.59 vs. 37.63 years, P= 0.006) and more often obese or with overweight (83.3 vs. 60.9%, P= 0.01). Frequency of metabolic syndrome as a whole entity was higher among patients with GERD than those without GERD (50 vs. 19.56%; P= 0.002) with a crude odds ratio of 4.11 (95% confidence interval: 1.66-10.14). Multivariate regression analysis showed that metabolic syndrome as well as an age ≥ 30 years were independent factors associated to GERD but not BMI and sex. Abnormal waist circumference and fasting glucose level ≥ 100 mg/L were the only independent factors among the five components of metabolic syndrome. Metabolic syndrome but not BMI was an independent factor associated to GERD. These results confirm the hypothesis that central obesity is associated to GERD.

Circulating antimyenteric autoantibodies in Tunisian patients with idiopathic achalasia

The physiopathology of idiopathic achalasia is still unknown. The description of circulating antimyenteric autoantibodies (CAA), directed against enteric neurons in sera of patients, suggests an autoimmune process. Recent data showed controversies according to the existence and the significance of CAA. The aims of this study were to investigate whether CAA are detected in Tunisian patients with idiopathic achalasia and to look for associated clinical or manometrical factors with CAA positivity. Twenty-seven patients with idiopathic achalasia and 57 healthy controls were prospectively studied. CAA were assessed by indirect immunofluorescence on intestinal monkey tissue sections. Western blot on primate cerebellum protein extract and dot technique with highly purified recombinant neuronal antigens (Hu, Ri, and Yo) were further used to analyze target antigens of CAA. CAA were significantly increased in achalasia patients compared with controls when considering nuclear or cytoplasmic fluorescence patterns. (33% vs. 12%, P = 0.03 and 48% vs. 23%, P = 0.001 respectively). By immunoblot analysis, CAA did not target neuronal antigens, however 52/53 and 49 kDa bands were consistently detected. CAA positivity was not correlated to specific clinical features. The results are along with previous studies demonstrating high CAA prevalence in achalasia patients. When reviewing technical protocols and interpretation criteria, several discrepancies which could explain controversies between studies were noted.

Seroprevalence of Helicobacter pylori among Tunisian blood donors (outpatients), symptomatic patients and control subjects

OBJECTIVES

Helicobacter pylori is a worldwide infection, although little data are available in the Tunisian population. The aims of our study were to detect the prevalence of H. pylori in a blood-donor population (n=250) and in another population of hospital-consulting patients comprising 87 symptomatic patients and 59 controls, and to determine the factors that influence the prevalence.

MATERIALS AND METHODS

Study subjects answered a standardized questionnaire, and IgG anti-H. pylori and anti-cag were detected by ELISA. In the second population, culture and cagA polymerase chain reaction were performed.

RESULTS

The seroprevalence of H. pylori in blood donors was 64%, and 11% had anti-cag. All patients positive for anti-cag were also positive for anti-H. pylori antibodies. The seroprevalence of H. pylori was 99.3% in the hospital-consulting patients, of whom 55.5% were positive for anti-cag. The difference between the anti-cag and symptomatic patients (66.7%) and controls (39%) was significant. Symptomatic patients had a higher rate of anti-cag (66.7%) compared with the controls (39%) and blood donors (11%).

CONCLUSION

H. pylori seroprevalence in blood donors is low (64%) compared with symptomatic patients (99.3%), and anti-cag was statistically associated with symptomatic patients and pathology. Also, some environmental factors were correlated with H. pylori seroprevalence.

Induction of apoptosis in human lymphoblastoid cells by kaempferol 3-O-β-isorhamninoside and rhamnocitrin 3-O-β-isorhamninoside from Rhamnus alaternus L. (Rhamnaceae)

OBJECTIVE

Kaempferol 3-O-β-isorhamninoside (K3O-ir) and rhamnocitrin 3-O-β-isorhamninoside (R3O-ir) from Rhamnus alaternus L leaves are investigated for their ability to induce apoptosis in human lymphoblastoid cells. We have attempted to characterize apoptotic pathway activated by these two flavonoids.

MATERIAL AND METHODS

Apoptosis of the human TK6 lymphoblastoid cell line was detected by DNA fragmentation, PARP cleavage and by evaluating caspase activity.

RESULTS

Apoptosis was observed after 24- and 48-h incubation of the cells with the tested compounds. DNA fragmentation was observed after treatment with flavonoids; this was confirmed by demonstration of PARP cleavage. Caspase-3 and caspase-8 activities were induced by both K3O-ir and R3O-ir flavonoids showing highest activity with compound concentration of 400 μg/ml.

CONCLUSION

We have demonstrated that K3O-ir and R3O-ir induce apoptosis in human lymphoblastoid cells by the extrinsic pathway of apoptosis.

Effect of pantoprazole in patients with chronic laryngitis and pharyngitis related to gastroesophageal reflux disease: clinical, proximal, and distal pH monitoring results

Few studies had evaluated the results of proton pump inhibitors on distal and proximal pH recording using a dual-channel probe. The aim of this study was to determine the clinical and pH-metric effect of treatment with pantoprazole 80 mg for 8 weeks in patients with ear, nose, and throat (ENT) manifestations of gastroesophageal reflux disease associated with pathological proximal acid exposure. We conducted a prospective open study. Patients included had to have chronic pharyngitis or laryngitis, and a pathological gastroesophagopharyngeal reflux. All patients received treatment with pantoprazole 80 mg daily for 8 weeks. One week after the end treatment, patients had a second ENT examination and a 24-hour pH monitoring using dual-channel probe. We included 33 patients (11 men, 22 women). A pathological distal acid reflux was found in 30 patients (91%). After treatment, the improvement of ENT symptoms was found in 51.5% of patients. Normalization of 24-hour proximal esophageal pH monitoring was observed in 22 patients (66%). After treatment, the overall distal acid exposure, the number of distal reflux events, and the number of reflux during more than 5 minutes were significantly decreased (respectively: 19.4% vs 7.2% [P < 0.0001], 62.7 vs 28.4 [P < 0.0001], and 10.4 vs 3.9 [P < 0.0001] ). Similarly, in proximal level, the same parameters were significantly decreased after treatment (respectively: 6.8% vs 1.6% [P < 0.0001], 32.6 vs 8.1 [P < 0.0001], and 3.4 vs 0.6 [P= 0.005] ). Treatment with pantoprazole reduced the frequency and severity of gastroesophagopharyngeal acid reflux in patients with chronic pharyngitis and laryngitis.

[Colonic expression of gamma-interferon and interleukin-10 in Crohn's disease and ulcerative colitis]

OBJECTIVE

The aim of this study was to investigate mucosal expression of INF-gamma and IL-10 in patients with Crohn's disease (CD) or ulcerative colitis (UC).

METHODS

Fourteen patients with CD and 11 patients with ulcerative colitis participated and 7 healthy subjects were also included. Study of the mucosal expression of INF-gamma and IL-10 was conducted using biopsies from healthy and damaged colons, using the inverse transcription and genetic amplification (RT-PCR) technique in real time (Taqman). Our results were expressed as ratio between messenger cytokine (mRNA) levels and ribosomal RNA level of a reference molecule (rRNA 18S), then multiplied by 108.

RESULTS

In the cases of Crohn's disease, the mucosa expressed increased INF-gamma and IL-10 compared with controls (respective medians: 23.03 vs. 1.87 p=0.04 and 20.61 vs. 2.13 p=0.08). A strong positive correlation was found in the mucosal expression of IL-10 and INF-gamma during CD (r=0.9 p<0.0001). In contrast, in patients with UC, the expression of INF-gamma and IL-10 were comparable to those observed in the controls (7.18 vs. 2.18 p=0.36 and 3.66 vs. 1.87 p=0.44).

CONCLUSION

During Crohn's disease, the expression of both IL-10 and INF-gamma was increased and strongly correlated, compared with the controls.

Familial cases of glomerulonephritis complicating Crohn's disease

A part from nephrolithiasis, renal involvement is rare in the course of Crohn's disease, particularly glomerulonephritis. On the other hand, while onset of Crohn's disease is strongly influenced by environmental and genetic factors, little is known regarding influence of these factors on extra intestinal manifestations. We report a familial case of glomerulonephritis that occurred in a 38-year old woman and her mother, 59 years old with a 7-year and a 37 year history of stenosing ileocolonic disease, respectively. Both of them developed peripheral oedema with nephrotic syndrome during the course of their Crohn's disease while they had no intestinal symptoms and were not receiving any maintenance therapy. Renal function was conserved in the former while the latter developed renal failure and had already small size kidneys on abdominal sonography. Thus, renal biopsy had been performed only in the former patient and had showed membranous glomerulonephritis. Investigations showed no other underlying disease than Crohn's disease. Through this report we emphasis possible genetic influence on extra intestinal manifestations, particularly glomerulonephritis, in Crohn's disease patients.

Antigenotoxic and Antioxidant Activities of Fruit Extracts from (Tunisian) Pistacia Lentiscus

Genotoxic and antigenotoxic activities against direct acting mutagen nifuroxazide, and indirect acting genotoxin aflatoxine B1 (AFB1) of extracts prepared from fruits of Pistacia lentiscus, were studied using the SOS chromotest with Escherichia coli PQ 37 as a tester organism. It was found that different extracts showed no genotoxicity when tested with E. coli PQ 37 strain either with or without microsomal extract. On the other hand, our results showed that ethyl acetate fraction and total oligomers flavonoids (TOF) extract obtained from P. lentiscus significantly decreased the genotoxicicity induced by AFB1 (10 μg/assay) and nifuroxazide (20 μg/assay). In addition to antigenotoxic activity, these extracts showed an important free radical scavenging activity towards the 2,2-diphenyl-2-picrylhydrazyl (DPPH) free radical and an important antioxidant activity using xanthine/xanthine oxidase system.

[A previously unreported late complication of Finney strictureplasty]

We report the case of a 23 year old woman, treated for Crohn's disease for 11 years. She was operated on for multiple obstructing jejuno-ileal strictures using strictureplasty technique. Nine stricturoplasties of Heineke-Mikulicz type and one Finney type were performed without immediate postoperative complication. The patient received Imurel(R) and remained in remission for 15 months. Peritonitis due to a perforation of the Finney strictureplasty required re-operation; an ileostomy was performed. Such a late complication of a strictureplasty has not previously been reported in the literature. Although this complication was severe, the indication for this procedure in the surgical management of Crohn's complications should not be modified.