ARTICLE IN PRESS Toxicon xxx (2009) 1–6 Contents lists available at ScienceDirect Toxicon journal homepage: www.elsevier.com/locate/toxicon Consumption of fumonisin B1 for 9 days induces stress proteins along the gastrointestinal tract of pigs Jean-Paul Lalle`s a, *, Martin Lessard b, Isabelle P. Oswald c, Jean-Claude David a a INRA, UMR 1039, SENAH, Domaine de la Prise, F-35590 Saint-Gilles, France Agriculture and Agri-Food Canada, Dairy and Swine Research and Development Centre, Lennoxville, Que´bec, Canada J1M 1Z3 c INRA, UR66, Unite´ de Pharmacologie-Toxicologie, 180 chemin de Tournefeuille, BP 93173, F-31027 Toulouse Cedex 03, France b a r t i c l e i n f o a b s t r a c t Article history: Received 23 February 2009 Received in revised form 23 July 2009 Accepted 24 July 2009 Available online xxxx Fumonisin B1 (FB1) is a mycotoxin which alters intestinal epithelial cell physiology and barrier properties, and accumulates in the colon. Data on effects of FB1 on stress proteins in the gastrointestinal tract (GIT) are lacking. Therefore, we hypothesized that repeated consumption of FB1 alters GIT tissue levels of stress proteins. This was tested using 36 weaned pigs fed a FB1 solution (n ¼ 18) or the vehicle (control; n ¼ 18) for 9 days. The pigs were then slaughtered, the organs were weighed and GIT tissues were collected for assessing GIT integrity, and for analysing stress proteins by Western blotting and densitometry (n ¼ 7 in each group). FB1 had little effects on growth rate but the liver was heavier (P < 0.01) in FB1-fed pigs. aB crystallin and COX-1 concentrations were eight-fold and 12-fold higher in the colon of FB1-fed pigs than in the controls (P < 0.0001). Concentrations of COX-1 and nNOS in the stomach, HSP 70 in the jejunum and HO-2 in the colon were also higher in FB1-fed pigs (P < 0.05 to P < 0.001). In conclusion, the FB1 extract drastically enhanced colonic levels of aB crystallin and COX-1, with milder increases in other stress proteins along the GIT of pigs. The data suggest that the colon is an important target for FB1-induced stress responses. Ó 2009 Elsevier Ltd. All rights reserved. Keywords: Fumonisin B1 Gastrointestinal tract Pig Stress proteins 1. Introduction Mycotoxins are secondary metabolites of fungi contaminating food ingredients. Their repeated consumption represents a potential health hazard for humans and animals (Oswald and Comera, 1998; CAST, 2003). Fumonisins are produced by Fusarium verticillioides which is commonly found on maize grains and related products. Fumonisin B1 (FB1) is the most abundant fumonisin occurring naturally in contaminated foods and is believed Abbreviations: BW, body weight; COX, cyclooxygenase; FB1, fumonisin B1; HO, heme oxygenase; GIT, gastrointestinal tract; HSP, heat shock protein; IEC, intestinal epithelial cell; INRA, Institut National de la Recherche Agronomique; NO, nitric oxide; NOS, NO synthase (iNOS: inducible, nNOS: neuronal). * Corresponding author. Tel.: þ33 2 23 48 53 59; fax: þ33 2 23 48 50 80. E-mail address: Jean-Paul.Lalles@rennes.inra.fr (J.-P. Lalle`s). to be the most toxic among the fumonisin family (Voss et al., 2007). Various species-specific mycotoxicosis in farm animals, including equine leukoencephalomalacia and porcine pulmonary edema are caused by FB1. This mycotoxin is also responsible for hepatotoxic and nephrotoxic alterations in rats (Voss et al., 2007). In pigs, consumption of an FB1-rich maize extract for 9 days increases gut colonisation by enteric pathogens (Oswald et al., 2003) and depresses immune responses (Taranu et al., 2005). The major functions of the gastrointestinal tract (GIT) are digestion, nutrient absorption and barrier defence against xenobiotics and enteric pathogens. Fumonisin B1 has been reported to exert direct toxic effects on the structure, cellularity and functions of the gut (Bouhet and Oswald, 2007). Low doses of FB1 reduce cytokine response of intestinal epithelial cells (IEC), cell viability via inhibition of cell proliferation and induction of apoptosis while higher doses are cytotoxic (Schmelz et al., 1998; Bouhet et al., 2004, 0041-0101/$ – see front matter Ó 2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.toxicon.2009.07.027 Please cite this article in press as: Lalle`s, J.-P., et al., Consumption of fumonisin B1 for 9 days induces stress proteins along the gastrointestinal tract of pigs, Toxicon (2009), doi:10.1016/j.toxicon.2009.07.027 ARTICLE IN PRESS J.-P. Lalle`s et al. / Toxicon xxx (2009) 1–6 2 2006). Intestinal barrier function of IEC lines is also altered following prolonged exposure to FB1 (Bouhet et al., 2004). However, much of the work on fumonisins and GIT epithelial cell viability and function was done in vitro. Therefore, more in vivo work is needed. Mechanisms of toxicity for fumonisins are complex (Soriano et al., 2005; Voss et al., 2007). Fumonisin B1 is structurally similar to the sphingolipids sphingosine and sphinganine and is known to inhibit the enzyme ceramide synthase, thus disrupting the de novo biosynthesis of ceramide and sphingolipid metabolism. Ceramide synthase inhibition leads to reduced levels of ceramide and to the accumulation of sphinganine and sphingosine. These free sphingoid bases are proapototic, cytotoxic and growth inhibitors, suggesting their role in FB1 toxicity (Soriano et al., 2005; Voss et al., 2007). Phosphorylated sphinganine and sphingosine also could be involved in some toxic effects of FB1 (Gon et al., 2005). In vivo exposure to FB1 alters glycolipid distribution and sphinganine to sphingosine ratio in small intestinal tissues of mice (Enongene et al., 2000) and pigs (Loiseau et al., 2007), and increases plasma levels of free sphinganine, sphinganine-1 phosphate and S1P in pigs (Piva et al., 2005). In vitro and in vivo data have reported effects of FB1 on stress proteins in cells from the liver, the kidney and the immune system, including heat shock proteins (HSP) 25 and HSP 70 (Liu et al., 2002; Rumora et al., 2007), cyclooxygenase 2 (COX-2) (Meli et al., 2000) and inducible NO synthase (iNOS) (Suzuki et al., 2007). However, there is no information to date for supporting any effects of FB1 on stress proteins in the GIT. This is surprising because this organ is the first to be in contact with mycotoxins ingested with the food. In addition, FB1 was reported to accumulate in the colon in comparison with the stomach or the small intestine (Prelusky et al., 1996). Using radio-labelled FB1, these authors estimated that after 24 days of feeding pigs with a feed contaminated with 3 (day 1–13) and 2 (day 14–24) mg/kg feed, the concentrations of FB1 and its metabolites at day 24 reached 160 and 65 ng/g tissue for the liver and the kidney, respectively. The corresponding concentrations for the stomach, the small intestine and the colon could be estimated as 40, 33 and 583 ng/g tissue, thus showing a 15-fold higher tissue concentration in the colon as compared to the stomach or the small intestine. Therefore, toxic stress induced by FB1 may be higher in the colon than in rest of the GIT. The aim of this work was to test the hypothesis that repeated consumption of an FB1-rich maize extract induces stress protein responses along the GIT, and especially in the colon. 2. Materials and methods 2.1. Preparation of FB1 extract The mycotoxin FB1 extract was obtained after in vitro culture of the high FB1-producing F. verticillioides strain NRRL 34281 (Oswald et al., 2003). Briefly, sterilized maize was inoculated with F. verticillioides and was incubated for 4 weeks at 25 C. Thereafter, the culture was extracted with acetonitrile–water, filtered, and concentrated with a rotary evaporator until total removal of acetonitrile. The fumonisin extract was analysed for FB1 by quantitative planar chromatography (Le Bars et al., 1994). Other fumonisins and other mycotoxins were analysed by gas chromatography and mass spectrometry, using the same references as Mirocha et al. (1990). This culture extract contained 2.3 mg/mL of FB1 and much lower levels of fumonisin B2 (0.34 mg/mL) and B3 (0.38 mg/mL) (Marin et al., 2006). Other mycotoxins including deoxynivalenol, fusarochromanone or trichothecenes were not detected in this extract (Marin et al., 2006). 2.2. Animals, feeding and experimental design The experiment was conducted under the guidelines of the French Ministry of Agriculture for animal research. Thirty-six castrated male piglets [Pietrain (Landrace Large White)] from the experimental herd of the Institut National de la Recherche Agronomique (INRA) at Saint-Gilles, France were weaned at 28 days of age and used in a complete block experimental design. Pairs of piglets were selected within a litter on the basis of close growth rates until and body weights (BW) at 7 days post-weaning. Pigs within pairs were allocated randomly to either the control or FB1-treated groups. Average BW at the initiation of FB1 extract administration was 10.87 (SE) 0.35 and 10.94 0.35 kg for the control and FB1-treated groups, respectively. Male pigs were used because of their higher immune sensitivity to FB1 as compared to female pigs (Marin et al., 2006). Pigs within pairs were allocated randomly to either the control or FB1-treated groups and they were housed into individual cages (0.6 0.8 m). The pigs were fed throughout the experimental period with a weaning diet containing the following ingredients (g/kg food): wheat 234.00; maize 280.00; barley 172.16; soya bean meal 266.30; and sunflower oil 4.50. The maize used in this study was assumed to be devoid of fumonisins. The daily amount of weaning food consumed by each pig during the experimental period was set at 75% of energy requirements established at 960 kJ net energy/BW (kg)0.75 per day according to INRA recommendations (INRA, 2007). This was made for limiting differences in food intake between experimental groups of pigs because FB1contaminated food can affect voluntary food intake (Rotter et al., 1996). The amount of food offered was adjusted daily on the basis of the BW and estimated daily weight gain of each pig. Pigs were weighed twice a week. During the experimental period, FB1 pigs received orally a bolus of the FB1 extract (1.5 mg FB1/kg BW) diluted in a 20% solution of glucose (used as a sweetener) daily for 9 days. This dose corresponded to approximately 25–30 ppm in the food and was previously shown to increase sphinganine to sphingosine ratio and to alter glycolipid distribution in the jejunal tissue of weaned pigs (Loiseau et al., 2007). Control pigs were orally dosed with the glucose solution without FB1 extract. At completion of the trial and 1.5 h after the last meal, pigs were euthanised by exsanguination following electronarcosis. 2.3. Organ weight and gastrointestinal tissue collection After laparotomy, the liver, the lungs, the spleen and the pancreas were collected and weighed. The whole GIT was Please cite this article in press as: Lalle`s, J.-P., et al., Consumption of fumonisin B1 for 9 days induces stress proteins along the gastrointestinal tract of pigs, Toxicon (2009), doi:10.1016/j.toxicon.2009.07.027 ARTICLE IN PRESS J.-P. Lalle`s et al. / Toxicon xxx (2009) 1–6 removed and the stomach, the small intestine, the caecum and the colon were isolated. The small intestine was divided into three segments (small intestine 1, 2 and 3) equal in length. The weight of fresh tissues from the small intestine and colon were determined after emptying the full segments from digesta contents, rinsing with cold saline and gently drying with absorbent tissue. Pieces (0.5 0.5 cm) of intestinal tissues were taken in the middle of each segment from each pig (n ¼ 18 per treatment) for histo-morphometry. They were placed in phosphate-buffered formalin (10%, pH 7.6) for 24 h at 4 C, then washed and stored in ethanol:water (75:25, v:v) until measurements. Pieces (0.5 0.5 cm) of stomach (pylorus), mid jejunum (¼segment 2 of the small intestine) and proximal colon (50 cm distal to the ileo-cecal junction) were collected from 7 pigs randomly chosen per treatment, immediately frozen in liquid nitrogen and kept at 80 C until analysis of stress proteins. 2.4. Villus-crypt morphology along the small intestine In order to evaluate intestinal integrity, the tissue samples of intestinal segments previously fixed in buffered formalin were microdissected for villi and crypts according to the technique of Goodlad et al. (1991). Ten to 15 villi and crypts per sample were measured for their length and width using image analysis as previously reported (David et al., 2002). The obtained values were averaged per villi and crypts for each tissue sample prior to statistical analysis. All the measurements were carried out blind with regard to the experimental treatments. 2.5. Tissue concentrations of stress proteins along the GIT Proteins were extracted from GIT tissues and assayed as described previously (Nefti et al., 2005). Briefly, the extraction was carried out on ice in 60 mM Tris buffer, pH 6.8, added with 10% glycerol and 3% SDS. The protease inhibitor Antagosan (Hoescht, Lyon, France) and the reducing agent b-mercaptoethanol (Sigma, 5%) were added to the extraction buffer just before use. After centrifugation, the supernatant was collected, and protein concentration determined (Nefti et al., 2005). Extracted tissue proteins were then separated by SDS-PAGE electrophoresis. Equal amounts of proteins were loaded onto a 13% acrylamide gel with a 4% stacking acrylamide gel. Migration was conducted in a 25 mM Tris buffer (pH 7.6) containing 0.1% SDS and 0.2 M glycine. After separation, proteins were transferred onto Hybond C membranes (Amersham, Piscataway, NJ). Stress proteins were detected using Western blotting. The primary antibodies against aB crystallin, heat shock proteins HSP 27 and HSP 70, and b-actin used in this study are presented in Table 1. All these primary antibodies were previously shown by these authors to recognise stress proteins in various swine tissues, including GIT segments. Expression of b-actin was used for checking the equal protein load across gel tracks. The same secondary antibody (anti-rabbit) coupled with horseradish peroxidase as reported previously (Louapre et al., 2005; Nefti et al., 2005; David et al., 2006) was used in the present work to reveal 3 the presence of different stress proteins under study and of b-actin on the membranes. Band densities were obtained by scanning the membranes using a phosphor imager (Quantum Appligene, Illkirch, France). Density data were standardized within membranes by expressing the density of each band of interest relative to that of b-actin in the same lane. 2.6. Statistical analysis Growth performance, feed intake, feed conversion and anatomical data were analysed using the MIXED procedure of the Statistical Analysis System (SAS Institute Inc., Cary, NC, USA). The effect of replication was tested using the residual variation between pairs as the error. The effect of the diet was tested against residual variations within pairs of pigs as the error. Final BW was taken as a covariate in the analysis of organ and GIT weight data. Stress protein data were obtained from pigs randomly chosen within groups. Therefore, they were analysed by t-test for comparing the FB1 group to the control using the GLM procedure of SAS. Data are presented as means and SE. Differences were declared significant at P < 0.05. 3. Results 3.1. Growth performance, food intake and conversion, and organ weight The pigs from both experimental groups grew similarly during the experimental period (final BW after the 9-day treatment with FB1 extract: 13.67 0.44 and 13.65 0.61 kg for the control and FB1-treated pigs, respectively). Food intake was not significantly influenced by the oral administration of FB1 extract (4.04 0.15 and 3.96 0.27 kg over the 9-day period for the control and FB1-treated pigs, respectively). However, food conversion ratio during the experimental period was lower (P ¼ 0.04) in pigs treated with FB1 extract as compared to controls (1.21 0.05 and 1.33 0.13 kg of food/ kg of BW gain). The weight of the liver was higher (P < 0.01) and that of the spleen tended to be lower (P ¼ 0.06) in the FB1-fed pigs compared to the controls (liver: 321 8 and 352 10 g; spleen: 26.5 1.3 and 23.7 1.5 g). The weights of the lungs, the pancreas and of fresh tissues of the stomach, the small intestine, the caecum and the colon were not affected by the intake of FB1 extract for 9 days (data not shown). 3.2. Intestinal villous-crypt architecture There were no differences (P 0.05) between treatment groups for the length, width, perimeter or surface area of villi and crypts in the three small intestinal segments studied (data not shown). 3.3. Tissue concentrations of heat shock proteins, cyclooxygenases, heme oxygenases and nitric oxide synthases along the GIT Tissue relative concentrations of aB crystallin in the stomach and the jejunum were not influenced by FB1 Please cite this article in press as: Lalle`s, J.-P., et al., Consumption of fumonisin B1 for 9 days induces stress proteins along the gastrointestinal tract of pigs, Toxicon (2009), doi:10.1016/j.toxicon.2009.07.027 ARTICLE IN PRESS J.-P. Lalle`s et al. / Toxicon xxx (2009) 1–6 4 Table 1 Origins, dilutions and references of primary antibodies used for detecting stress proteins and b-actin by Western blotting. Protein Abbreviation Origin Dilution Reference aB crystallin aB crystallin Cyclooxygenase 1 Cyclooxygenase 2 Heat shock protein 27 Heat shock protein 70 Heme oxygenase 1 Heme oxygenase 2 Inducible nitric oxide synthase Neuronal nitric oxide synthase b-actin COX-1 COX-2 HSP 27 HSP 70 HO-1 HO-2 iNOS nNOS b-actin Generous gift from H Lambert, Hotel Dieu de Quebec, Canada Cayman laboratory Tebu, Le Perray, France (ref. 160108) Cayman laboratory Tebu, Le Perray, France (ref. 160107) Generous gift from H Lambert, Hotel Dieu de Quebec, Canada StressGen Biotechnologies, Victoria, BC, Canada (ref. SPA 812) Stressgen, Collegeville, PA, USA (ref. OSA-100) Stressgen, Collegeville, PA, USA (ref. OSA-155) Santa Cruz Biotechnology, Santa Cruz, CA, USA (ref. SC 651) Sigma–Aldrich, St. Quentin Fallavier, France (ref. N-7155) Sigma–Aldrich, St. Quentin Fallavier, France (ref. A-9044) 1:1000 1:250 1:200 1:1000 1:2000 1:500 1:500 1:500 1:1250 1:1000 Nefti et al., 2005 David et al., 2006 David et al., 2006 Nefti et al., 2005 Nefti et al., 2005 Louapre et al., 2005 David et al., 2006 Louapre et al., 2005 Louapre et al., 2005 Nefti et al., 2005 consumption (P 0.05) but aB crystallin concentration in the colon was eight-fold higher in the FB1-fed pigs than in the controls (P < 0.001) (Table 2). Concentrations of COX-1 in the stomach and the colon were higher in FB1-treated pigs than in the controls (P ¼ 0.043 and P < 0.0001). COX-1 was not detected in the jejunum and COX-2 was never detected along the GIT of pigs. Concentrations of HSP 27 along the GIT remained unaffected by FB1 treatment (P 0.05). Concentration of HSP 70 was higher in the jejunum of FB1-treated pigs as compared to the controls (P ¼ 0.004), with no differences for the other GIT sites. Heme oxygenase 1 was not detected in GIT of pigs. Concentration of HO-2 was higher in the colon of FB1-treated pigs than in the controls (P < 0.001), with no differences in the stomach and the jejunum (P 0.05). The inducible nitric oxide synthase iNOS was not detected along the GIT. Neuronal nNOS was detected only in stomach tissue and at a higher concentration in the FB1-treated pigs than in the controls (P ¼ 0.030). Table 2 Influence of the FB1 extract on the relative tissue expression of stress proteins along the GIT of pigs (means SE, n ¼ 7 per treatment). Stress proteina GIT site Treatment P-value Control FB1 aB Crystallin Stomach Jejunum Colon 58.6 1.3 19.0 1.5 7.1 0.9 57.4 2.5 21.4 2.2 59.7 2.1 0.67 0.34 <0.0001 COX-1 Stomach Jejunum Colon 53.4 2.8 ndb 4.3 0.8 60.3 1.7 nd 52.4 5.2 0.043 <0.0001 HSP 27 Stomach Jejunum Colon 41.6 1.7 30.4 1.4 44.3 1.4 44.7 2.3 32.4 1.5 43.9 1.1 0.26 0.32 0.80 HSP 70 Stomach Jejunum Colon 84.4 1.7 33.4 1.2 55.3 4.6 86.0 0.9 38.3 0.9 53.3 2.1 0.40 0.004 0.68 HO-2 Stomach Jejunum Colon 78.0 2.6 63.1 3.3 60.3 1.1 77.4 1.4 64.6 1.8 75.3 3.3 0.84 0.69 <0.001 nNOS Stomach Jejunum Colon 44.3 1.3 nd nd 47.9 0.7 nd nd 0.030 a COX-2, HO-1 and iNOS were never detected in the stomach, the jejunum and the colon. b Not detected. 4. Discussion The major finding of the present work is that oral administration of a FB1-rich extract drastically increased tissue levels of aB crystallin and COX-1 in the colon. Milder increases in the concentration of various stress proteins along the GIT were also noted. These effects may be essentially attributable to FB1 which is considered as the most toxic fumonisin (3). Although specific influences of low levels of FB2 and FB3 on the GIT cannot be excluded, such effects have not been reported in the literature to date. It is the first time that over-expressions of aB crystallin and COX-1 (and of HO-2 to a lesser extent) are reported in the colon in response to FB1 consumption. Our data suggest that the colon is highly sensitive and, therefore, responsive to the deleterious effects of this mycotoxin. The stronger stress responses observed in the colon of FB1-treated pigs may be related to the greater accumulation of FB1 in the colon, comparatively to the stomach or the small intestine (Prelusky et al., 1996). aB Crystallin is constitutively expressed along the porcine GIT during early development in the absence of additional stress (Tallot et al., 2003). This small HSP (MW ¼ 20 kDa) is involved in the modulation of cell cytoskeleton, the inhibition of apoptosis and the ability of cells to increase their resistance to oxidative injury (Arrigo et al., 2007). aB crystallin is strongly over-expressed in colonic tissue of neonatal pigs subjected to hypoxia (Nefti et al., 2005). The enhanced aB crystallin concentration in the colon observed in this work may be due to the potential of FB1 to increase lipid peroxidation. Indeed, FB1 is a potent inducer of oxidative stress and lipid peroxidation in intestinal epithelial cells (Kouadio et al., 2005). Tissue induction of aB crystallin in response to FB1 may possibly confer enhanced colonic protection, as observed in a mice model of inflammation (Masilamoni et al., 2005), but this remains to be investigated in pigs. Cyclooxygenases are enzymes involved in the production of pro-inflammatory mediators. The COX-1 isoform is present constitutively in the GIT while the COX-2 isoform is expressed in response to inflammatory stimuli (Warner and Mitchell, 2004). Cyclooxygenase 2 was not detected along the GIT of pigs in the present experiment. By contrast, COX-1 was largely over-expressed in colonic tissue of FB1 extract-treated pigs. Cyclooxygenase 1 may have an important role in mucosal defence against xenobiotics in the stomach (Gretzer et al., 2001) but little information is Please cite this article in press as: Lalle`s, J.-P., et al., Consumption of fumonisin B1 for 9 days induces stress proteins along the gastrointestinal tract of pigs, Toxicon (2009), doi:10.1016/j.toxicon.2009.07.027 ARTICLE IN PRESS J.-P. Lalle`s et al. / Toxicon xxx (2009) 1–6 available for the intestine. Blikslager et al. (2002) detected only low levels of COX-2 in porcine ileal tissues subjected to ischemic injury, and they concluded that both COX-1 and COX-2 may be involved in the recovery of porcine ileum in this model. A significant increase in colonic levels of HO-2 was observed in the pigs orally treated with the FB1-rich extract. Interestingly, a novel role for HO-2 in the regulation of inflammatory and reparative responses to injury was recently documented (Seta et al., 2006). This cytoprotection mechanism brought about by increased concentration of HO-2 in the colon, although of limited magnitude here, may have contributed to reinforce the protective effects of aB crystallin and COX-1 against toxic effects of FB1 in this organ. The FB1-rich maize extract administered orally to pigs induced (small) increases in tissue levels of COX-1 and nNOS in the stomach and HSP 70 in the small intestine. Gastric COX-1 protein over-expression as observed in the present study may have contributed to increase the protection of this organ against deleterious effects of toxic compounds such as FB1. This is supported by published data showing that acid damage to the gastric mucosa was alleviated by specific inhibitors of COX-1 (Gretzer et al., 2001). Gastric protection may have been further enhanced in the pigs consuming FB1 by the increase in nNOS levels in gastric tissues. Although NO is known to regulate many processes in the GIT, the respective roles of endothelial NOS (eNOS), iNOs and nNOS in GIT defence and protection against injuries and inflammation are still unclear. Data are even controversial regarding the involvement of nNOS in intestinal inflammation, being protective or non-protective (Beck et al., 2004; Vallance et al., 2004). The only heat shock protein to be (slightly) enhanced following FB1 oral exposure was HSP 70 in the jejunum. This response may be protective to the intestine (Otaka et al., 2006). The present observation is consistent with the reported FB1-induced increase in HSP 70 protein expression in alveolar macrophages (Liu et al., 2002), in rat kidney (Rumora et al., 2007) and in fibroblasts (Galvano et al., 2002). We did not observe any response on HSP 27 expression in GIT tissues. This result contrasts with the over-expression of HSP 27 in renal and liver tissues of rats chronically administered FB1 i.p. (Rumora et al., 2007) but is consistent with the lack of HSP 27 response in the GIT following neonatal hypoxia in pigs (Nefti et al., 2005). In terms of underlying mechanisms, stress responses may be linked with changes in GIT tissue sphingolipid metabolism brought about by FB1. Fumonisin B1 in an inhibitor of ceramide synthase, resulting in decreased ceramide concentration and increased sphinganine and sphingosine concentrations (Soriano et al., 2005; Voss et al., 2007). Ceramide induced by heat shock or increased intracellularly was shown to stimulate gene transcription of aB crystallin in fibroblast cells (Chang et al., 1995). Regarding heat shock proteins, HSP 70 was suppressed by ceramide in heat shock-induced HL-60 cell apoptosis (Kondo et al., 2000). In the present study, aB crystallin was strongly overexpressed in the colon while HSP 70 was unaffected. Therefore, the pathways between FB1, changes in sphingolipid metabolism and stress responses may be different 5 from those related to heat shock and demonstrated in cell models (Chang et al., 1995; Kondo et al., 2000). This area clearly needs new investigations. The effect of the treatment with the FB1 extract on pig growth performance and feed conversion was limited, probably because the period of FB1 administration was short (9 days) and because food intake was set at 75% of pig needs in order to limit food refusals. It is important to work at constant food intake because it is a major determinant of GIT growth and physiology. Interestingly, despite limited effects on BW, the 9-day treatment with the FB1 extract affected the weight of organs like the liver and the spleen. These changes are in agreement with the observation that FB1 is hepatotoxic (Voss et al., 2007) and is able to depress immune responses (Taranu et al., 2005). By contrast, the weight of the lung, the pancreas and the GIT and its segments were not modified in FB1-fed pigs, highlighting the differential sensitivity to this mycotoxin across GIT segments (Rotter et al., 1996). In conclusion, the present work provides evidence that the repeated consumption of a maize extract rich in fumonisin B1 increases tissue expression of aB crystallin and COX-1 in the colon, with milder increases in various stress proteins along the GIT. Our data highlight the complexity of the cytoprotection systems and GIT regional variations in the induced response. The underlying cellular and molecular mechanisms linking FB1 to stress proteins and GIT physiology need to be investigated further. Acknowledgement The authors thank the staff of the UMR SENAH for care of the animals, for slaughtering the pigs and for laboratory analysis. Thanks are also due to the Statistical Unit of the Dairy and Swine Research and Development Center of Agriculture and Agri-Food Canada at Lennoxville, Que´bec, Canada for the statistical analysis of data. The authors acknowledge INRA for supporting financially the one-year stay of Dr Martin Lessard at INRA Rennes, France and the ‘Mycotoxines’ Transversal program (number P00263). Conflicts of interest The authors declare that there are no conflicts of interest. References Arrigo, A.P., Simon, S., Gibert, B., Kretz-Remy, C., Nivon, M., Czekalla, A., Guillet, D., Moulin, M., Diaz-Latoud, C., Vicart, P., 2007. Hsp27 (HspB1) and alphaB-crystallin (HspB5) as therapeutic targets. FEBS Lett. 581, 3665–3674. Beck, P.L., Xavier, R., Wong, J., Ezedi, I., Mashimo, H., Mizoguchi, A., Mizoguchi, E., Bhan, A.K., Podolsky, D.K., 2004. Paradoxical roles of different nitric oxide synthase isoforms in colonic injury. Am. J. Physiol. Gastrointest. Liver Physiol. 286, G137–G147. Blikslager, A.T., Zimmel, D.N., Young, K.M., Campbell, N.B., Little, D., Argenzio, R.A., 2002. Recovery of ischaemic injured porcine ileum: evidence for a contributory role of COX-1 and COX-2. Gut 50, 615–623. Bouhet, S., Hourcade, E., Loiseau, N., Fikry, A., Martinez, S., Roselli, M., Galtier, P., Mengheri, E., Oswald, I.P., 2004. The mycotoxin fumonisin B1 alters the proliferation and the barrier function of porcine intestinal epithelial cells. Toxicol. Sci. 77, 165–171. Please cite this article in press as: Lalle`s, J.-P., et al., Consumption of fumonisin B1 for 9 days induces stress proteins along the gastrointestinal tract of pigs, Toxicon (2009), doi:10.1016/j.toxicon.2009.07.027 ARTICLE IN PRESS 6 J.-P. Lalle`s et al. / Toxicon xxx (2009) 1–6 Bouhet, S., Le Dorze, E., Peres, S., Fairbrother, J.M., Oswald, I.P., 2006. Mycotoxin fumonisin B1 selectively down-regulates the basal IL-8 expression in pig intestine: in vivo and in vitro studies. Food Chem. Toxicol. 44, 1768–1773. Bouhet, S., Oswald, I.P., 2007. The intestine as a possible target for fumonisin toxicity. Mol. Nutr. Food Res. 51, 925–931. CAST, 2003. Mycotoxins: Risks in Plants, Animals and Human Systems. Council for Agricultural Science and Technology, Ames, Iowa. Chang, Y., Abe, A., Shayman, J.A., 1995. Ceramide formation during heat shock: a potential mediator of alpha B-crystallin transcription. Proc. Natl. Acad. Sci. U S A 92, 12275–12279. David, J.C., Boelens, W.C., Grongnet, J.F., 2006. Up-regulation of heat shock protein HSP 20 in the hippocampus as an early response to hypoxia of the newborn. J. Neurochem. 99, 570–581. David, J.C., Grongnet, J.F., Lalle`s, J.P., 2002. Weaning affects the expression of heat shock proteins in different regions of the gastrointestinal tract of piglets. J. Nutr. 132, 2551–2561. Enongene, E.N., Sharma, R.P., Bhandari, N., Voss, K.A., Riley, R.T., 2000. Disruption of sphingolipid metabolism in small intestines, liver and kidney of mice dosed subcutaneously with fumonisin B1. Food Chem. Toxicol. 38, 793–799. Galvano, F., Russo, A., Cardile, V., Galvano, G., Vanella, A., Renis, M., 2002. DNA damage in human fibroblasts exposed to fumonisin B(1). Food Chem. Toxicol. 40, 25–31. Gon, Y., Wood, M.R., Kiosses, W.B., Jo, E., Sanna, M.G., Chun, J., Rosen, H., 2005. S1P3 receptor-induced reorganization of epithelial tight junctions compromises lung barrier integrity and is potentiated by TNF. Proc. Natl. Acad. Sci. U S A 102, 9270–9275. Goodlad, R.A., Levi, S., Lee, C.Y., Mandir, N., Hodgson, H., Wright, N.A., 1991. Morphometry and cell proliferation in endoscopic biopsies: evaluation of a technique. Gastroenterology 101, 1235–1241. Gretzer, B., Maricic, N., Respondek, M., Schuligoi, R., Peskar, B.M., 2001. Effects of specific inhibition of cyclo-oxygenase-1 and cyclo-oxygenase-2 in the rat stomach with normal mucosa and after acid challenge. Br. J. Pharmacol. 132, 1565–1573. INRA, 2007. InraPorcÒ. http://w3.rennes.inra.fr/inraporc/fr/. Kondo, T., Matsuda, T., Tashima, M., Umehara, H., Domae, N., Yokoyama, K., Uchiyama, T., Okazaki, T., 2000. Suppression of heat shock protein-70 by ceramide in heat shock-induced HL-60 cell apoptosis. J. Biol. Chem. 275, 8872–8879. Kouadio, J.H., Mobio, T.A., Baudrimont, I., Moukha, S., Dano, S.D., Creppy, E.E., 2005. Comparative study of cytotoxicity and oxidative stress induced by deoxynivalenol, zearalenone or fumonisin B1 in human intestinal cell line Caco-2. Toxicology 213, 56–65. Le Bars, J., Le Bars, P., Dupuy, J., Boudra, H., Cassini, R., 1994. Biotic and abiotic factors in fumonisin B1 production and stability. J. Assoc. Off. Anal. Chem. Int. 77, 517–521. Liu, B.H., Yu, F.Y., Chan, M.H., Yang, Y.L., 2002. The effects of mycotoxins, fumonisin B1 and aflatoxin B1, on primary swine alveolar macrophages. Toxicol. Appl. Pharmacol. 180, 197–204. Loiseau, N., Debrauwer, L., Sambou, T., Bouhet, S., Miller, J.D., Martin, P.G., Viade`re, J.L., Pinton, P., Puel, O., Pineau, T., Tulliez, J., Galtier, P., Oswald, I.P., 2007. Fumonisin B1 exposure and its selective effect on porcine jejunal segment: sphingolipids, glycolipids and transepithelial passage disturbance. Biochem. Pharmacol. 74, 144–152. Louapre, P., Grongnet, J.F., Tanguay, R.M., David, J.C., 2005. Effects of hypoxia on stress proteins in the piglet heart at birth. Cell Stress Chaperones 10, 17–23. Marin, D.E., Taranu, I., Pascale, F., Lionide, A., Burlacu, R., Bailly, J.D., Oswald, I.P., 2006. Sex-related differences in the immune response of weanling piglets exposed to low doses of fumonisin extract. Br. J. Nutr. 95, 1185–1192. Masilamoni, J.G., Jesudason, E.P., Bharathi, S.N., Jayakumar, R., 2005. The protective effect of a-crystallin against acute inflammation in mice. Biochim. Biophys. Acta 1740, 411–420. Meli, R., Ferrante, M.C., Raso, G.M., Cavaliere, M., Di Carlo, R., Lucisano, A., 2000. Effect of fumonisin B1 on inducible nitric oxide synthase and cyclooxygenase-2 in LPS-stimulated J774A.1 cells. Life Sci. 67, 2845–2853. Mirocha, C.J., Abbas, H.K., Vesonder, R.F., 1990. Absence of trichothecenes in toxigenic isolates of Fusarium moniliforme. Appl. Environ. Microbiol. 56, 520–525. Nefti, O., Grongnet, J.F., David, J.C., 2005. Overexpression of alphaB crystallin in the gastrointestinal tract of the newborn piglet after hypoxia. Shock 24, 455–461. Oswald, I.P., Comera, C., 1998. Immunotoxicity of mycotoxins. Rev. Med. Vet. 149, 585–590. Oswald, I.P., Desautels, C., Laffitte, J., Fournout, S., Peres, S.Y., Odin, M., Le Bars, P., Le Bars, J., Fairbrother, J.M., 2003. Mycotoxin fumonisin B1 increases intestinal colonization by pathogenic Escherichia coli in pigs. Appl. Environ. Microbiol. 69, 5870–5874. Otaka, M., Odashima, M., Watanabe, S., 2006. Role of heat shock proteins (molecular chaperones) in intestinal mucosal protection. Biochem. Biophys. Res. Commun. 348, 1–5. Piva, A., Casadei, G., Pagliuca, G., Cabassi, E., Galvano, F., Solfrizzo, M., Riley, R.T., Diaz, D.E., 2005. Activated carbon does not prevent the toxicity of culture material containing fumonisin B1 when fed to weanling piglets. J. Anim. Sci. 83, 1939–1947. Prelusky, D.B., Miller, J.D., Trenholm, H.L., 1996. Disposition of 14C-derived residues in tissues of pigs fed radiolabelled fumonisin B1. Food Addit. Contam. 13, 155–162. Rotter, B.A., Thompson, B.K., Prelusky, D.B., Trenholm, H.L., Stewart, B., Miller, J.D., Savard, M.E., 1996. Response of growing swine to dietary exposure to pure fumonisin B1 during an eight-week period: growth and clinical parameters. Nat. Toxins 4, 42–50. Rumora, L., Domijan, A.M., Grubisic´, T.Z., Peraica, M., 2007. Mycotoxin fumonisin B1 alters cellular redox balance and signalling pathways in rat liver and kidney. Toxicology 242, 31–38. Schmelz, E.M., Dombrink-Kurtzman, M.A., Roberts, P.C., Kozutsumi, Y., Kawasaki, T., Merrill Jr., A.H., 1998. Induction of apoptosis by fumonisin B1 in HT29 cells is mediated by the accumulation of endogenous free sphingoid bases. Toxicol. Appl. Pharmacol. 148, 252–260. Seta, F., Bellner, L., Rezzani, R., Regan, R.F., Dunn, M.W., Abraham, N.G., Gronert, K., Laniado-Schwartzman, M., 2006. Heme oxygenase-2 is a critical determinant for execution of an acute inflammatory and reparative response. Am. J. Pathol. 169, 1612–1623. Soriano, J.M., Gonza´lez, L., Catala´, A.I., 2005. Mechanism of action of sphingolipids and their metabolites in the toxicity of fumonisin B1. Prog. Lipid Res. 44, 345–356. Suzuki, H., Riley, R.T., Sharma, R.P., 2007. Inducible nitric oxide has protective effect on fumonisin B1 hepatotoxicity in mice via modulation of sphingosine kinase. Toxicology 229, 42–53. Tallot, P., Grongnet, J.F., David, J.C., 2003. Dual perinatal and developmental expression of the small heat shock proteins aB-crystallin and Hsp27 in different tissues of the developing piglet. Biol. Neonate 83, 281–288. Taranu, I., Marin, D.E., Bouhet, S., Pascale, F., Bailly, J.D., Miller, J.D., Pinton, P., Oswald, I.P., 2005. Mycotoxin fumonisin B1 alters the cytokine profile and decreases the vaccinal antibody titer in pigs. Toxicol. Sci. 84, 301–307. Vallance, B.A., Dijkstra, G., Qiu, B., van der Waaij, L.A., van Goor, H., Jansen, P.L., Mashimo, H., Collins, S.M., 2004. Relative contributions of NOS isoforms during experimental colitis: endothelial-derived NOS maintains mucosal integrity. Am. J. Physiol. Gastrointest. Liver Physiol. 287, G865–G874. Voss, K.A., Smith, G.W., Haschek, W.M., 2007. Fumonisins: toxicokinetics, mechanism of action and toxicity. Anim. Feed Sci. Technol. 137, 299–325. Warner, T.D., Mitchell, J.A., 2004. Cyclooxygenases: new forms, new inhibitors, and lessons from the clinic. FASEB J. 18, 790–804. Please cite this article in press as: Lalle`s, J.-P., et al., Consumption of fumonisin B1 for 9 days induces stress proteins along the gastrointestinal tract of pigs, Toxicon (2009), doi:10.1016/j.toxicon.2009.07.027
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