A Brazilian regional basic diet-induced chronic malnutrition drives liver inflammation with higher ApoA-I activity in C57BL6J mice.

Malnutrition is still considered endemic in many developing countries. Malnutrition-enteric infections may cause lasting deleterious effects on lipid metabolism, especially in children living in poor settings. The regional basic diet (RBD), produced to mimic the Brazilian northeastern dietary characteristics (rich in carbohydrate and low in protein) has been used in experimental malnutrition models, but few studies have explored the effect of chronic RBD on liver function, a central organ involved in cholesterol metabolism. This study aimed to investigate whether RBD leads to liver inflammatory changes and altered reverse cholesterol metabolism in C57BL6/J mice compared to the control group, receiving a standard chow diet. To evaluate liver inflammation, ionized calcium-binding adapter protein-1 (IBA-1) positive cell counting, interleukin (IL)-1ß immunohistochemistry, and tumor necrosis factor (TNF)-α and IL-10 transcription levels were analyzed. In addition, we assessed reverse cholesterol transport by measuring liver apolipoprotein (Apo)E, ApoA-I, and lecithin-cholesterol acyltransferase (LCAT) by RT-PCR. Furthermore, serum alanine aminotransferase (ALT) was measured to assess liver function. RBD markedly impaired body weight gain compared with the control group (P<0.05). Higher hepatic TNF-α (P<0.0001) and IL-10 (P=0.001) mRNA levels were found in RBD-challenged mice, although without detectable non-alcoholic fatty liver disease. Marked IBA-1 immunolabeling and increased number of positive-IBA-1 cells were found in the undernourished group. No statistical difference in serum ALT was found. There was also a significant increase in ApoA mRNA expression in the undernourished group, but not ApoE and LCAT, compared with the control. Altogether our findings suggested that chronic RBD-induced malnutrition leads to liver inflammation with increased ApoA-I activity.

A Brazilian regional basic diet-induced chronic malnutrition drives liver inflammation with higher ApoA-I activity in C57BL6J mice

Malnutrition is still considered endemic in many developing countries. Malnutrition-enteric infections may cause lasting deleterious effects on lipid metabolism, especially in children living in poor settings. The regional basic diet (RBD), produced to mimic the Brazilian northeastern dietary characteristics (rich in carbohydrate and low in protein) has been used in experimental malnutrition models, but few studies have explored the effect of chronic RBD on liver function, a central organ involved in cholesterol metabolism. This study aimed to investigate whether RBD leads to liver inflammatory changes and altered reverse cholesterol metabolism in C57BL6/J mice compared to the control group, receiving a standard chow diet. To evaluate liver inflammation, ionized calcium-binding adapter protein-1 (IBA-1) positive cell counting, interleukin (IL)-1β immunohistochemistry, and tumor necrosis factor (TNF)-α and IL-10 transcription levels were analyzed. In addition, we assessed reverse cholesterol transport by measuring liver apolipoprotein (Apo)E, ApoA-I, and lecithin-cholesterol acyltransferase (LCAT) by RT-PCR. Furthermore, serum alanine aminotransferase (ALT) was measured to assess liver function. RBD markedly impaired body weight gain compared with the control group (P<0.05). Higher hepatic TNF-α (P<0.0001) and IL-10 (P=0.001) mRNA levels were found in RBD-challenged mice, although without detectable non-alcoholic fatty liver disease. Marked IBA-1 immunolabeling and increased number of positive-IBA-1 cells were found in the undernourished group. No statistical difference in serum ALT was found. There was also a significant increase in ApoA mRNA expression in the undernourished group, but not ApoE and LCAT, compared with the control. Altogether our findings suggested that chronic RBD-induced malnutrition leads to liver inflammation with increased ApoA-I activity.

Amifostine reduces inflammation and protects against 5-fluorouracil-induced oral mucositis and hyposalivation.

Oral mucositis (OM) is a common and dose-limiting side effect of cancer treatment, including 5-fluorouracil (5-FU) and radiotherapy. The efficacy of the therapeutic measures to prevent OM is limited and disease prevention is not fully observable. Amifostine is a cytoprotective agent with a described anti-inflammatory potential. It is clinically used to reduce radiotherapy and chemotherapy-associated xerostomia. This study investigated the protective effect of amifostine on an experimental model of OM. Hamsters were divided into six groups: saline control group (5 mL/kg), mechanical trauma (scratches) of the right cheek pouch; 5-FU (60 and 40 mg/kg, ip, respectively, administered on days 1 and 2); amifostine (12.5, 25, or 50 mg/kg) + 5-FU + scratches. Salivation rate was assessed and the animals were euthanized on day 10 for the analysis of macroscopic and microscopic injury by scores. Tissue samples were harvested for the measurement of neutrophil infiltration and detection of inflammatory markers by ELISA and immunohistochemistry. 5-FU induced pronounced hyposalivation, which was prevented by amifostine (P<0.05). In addition, 5-FU injection caused pronounced tissue injury accompanied by increased neutrophil accumulation, tumor necrosis factor-alpha (TNF-α), and interleukin-1 beta (IL-1ß) tissue levels, and positive immunostaining for TNF-α, IL-1ß, and inducible nitric oxide synthase (iNOS). Interestingly, amifostine prevented the inflammatory reaction and consequently improved macroscopic and microscopic damage (P<0.05 vs 5-FU group). Amifostine reduced inflammation and protected against 5-FU-associated oral mucositis and hyposalivation.

Amifostine reduces inflammation and protects against 5-fluorouracil-induced oral mucositis and hyposalivation

Oral mucositis (OM) is a common and dose-limiting side effect of cancer treatment, including 5-fluorouracil (5-FU) and radiotherapy. The efficacy of the therapeutic measures to prevent OM is limited and disease prevention is not fully observable. Amifostine is a cytoprotective agent with a described anti-inflammatory potential. It is clinically used to reduce radiotherapy and chemotherapy-associated xerostomia. This study investigated the protective effect of amifostine on an experimental model of OM. Hamsters were divided into six groups: saline control group (5 mL/kg), mechanical trauma (scratches) of the right cheek pouch; 5-FU (60 and 40 mg/kg, ip, respectively, administered on days 1 and 2); amifostine (12.5, 25, or 50 mg/kg) + 5-FU + scratches. Salivation rate was assessed and the animals were euthanized on day 10 for the analysis of macroscopic and microscopic injury by scores. Tissue samples were harvested for the measurement of neutrophil infiltration and detection of inflammatory markers by ELISA and immunohistochemistry. 5-FU induced pronounced hyposalivation, which was prevented by amifostine (P<0.05). In addition, 5-FU injection caused pronounced tissue injury accompanied by increased neutrophil accumulation, tumor necrosis factor-alpha (TNF-α), and interleukin-1 beta (IL-1β) tissue levels, and positive immunostaining for TNF-α, IL-1β, and inducible nitric oxide synthase (iNOS). Interestingly, amifostine prevented the inflammatory reaction and consequently improved macroscopic and microscopic damage (P<0.05 vs 5-FU group). Amifostine reduced inflammation and protected against 5-FU-associated oral mucositis and hyposalivation.

Role of TRPV1 receptor in inflammation and impairment of esophageal mucosal integrity in a murine model of nonerosive reflux disease.

BACKGROUND: Microscopic inflammation and impairment of the esophageal epithelial barrier are considered relevant for perception of symptoms in patients with nonerosive reflux disease (NERD). In these patients, the receptor transient receptor potential vanilloid 1 (TRPV1) is overexpressed in the esophageal mucosa, but its role is not yet fully understood. We evaluated the role of TRPV1 in esophageal inflammation and mucosal barrier impairment in a murine model of NERD. METHODS: Nonerosive reflux disease was surgically induced in Swiss mice by pyloric substenosis and ligature of the gastric fundus, and the mice were killed 7 days post surgery. The experimental groups were: I, sham surgery (negative control); II, NERD untreated; III and IV, NERD + SB366791 or capsazepine (TRPV1 antagonists); and V, NERD + resiniferatoxin (for long-term desensitization of TRPV1). The esophagus was collected for western blotting and histopathology and for evaluation of wet weight, myeloperoxidase (MPO), keratinocyte-derived chemokine (KC), transepithelial electrical resistance (TEER), and basal permeability to fluorescein. KEY RESULTS: Compared to sham, NERD mice had increased esophageal wet weight and MPO and KC levels. The mucosa had no ulcers but exhibited inflammation. NERD mice showed mucosal TRPV1 overexpression, a more pronounced decrease in TEER at pH 0.5 (containing pepsin and taurodeoxycholic acid), and increased basal permeability. Pharmacological modulation of TRPV1 prevented esophageal inflammation development, TEER changes by acidic exposure, and increase in esophageal permeability. CONCLUSIONS & INFERENCES: The TRPV1 receptor has a critical role in esophageal inflammation and mucosal barrier impairment in NERD mice, suggesting that TRPV1 might be a pharmacological target in patients with NERD.

Morphological characterization of ckd in cats: Insights of fibrogenesis to be recognized.

Renal fibrosis is characterized by glomerulosclerosis and tubulointerstitial fibrosis and its pathogenesis is associated with the activity of mesenchymal cells (fibroblasts), being essentially characterized by a process of excessive accumulation resulting from the deposition of extracellular matrix components. The aim of this study was to characterize the morphological presentation of chronic and fibrotic lesions in the glomerular, tubular, interstitial, and vascular compartments in feline CKD, as well as the possible participation of myofibroblasts in renal fibrotic processes in this species. Cat kidneys were collected and processed according to the conventional techniques for light microscopy, circular polarization, immunohistochemistry, and electron microscopy. Fibrotic alterations were present in all compartments analyzed. The main findings in the glomerular compartment were different degrees of glomerular sclerosis, synechia formation, Bowman's capsule calcification, in addition to glomerular basement membrane thickening and pericapsular fibrosis. The tubulointerstitial compartment had intense tubular degeneration and the immunostaining in tubular cells for mesenchymal cell markers demonstrated the possibility of mesenchymal epithelial transition and consequent involvement of myofibroblasts in the development of interstitial tubule damage. Infiltration of inflammatory cells, added to vessel thickening and fibrosis, demonstrated the severity and role of inflammation in the development and perpetuation of damage. Thus, we may conclude that fibrotic lesions play a relevant role in feline CKD and the mechanism of perpetuation of these lesions need further elucidation regarding the origin and participation of myofibroblasts and consequent mesenchymal epithelial transition in this species.

Impact of acute undernutrition on growth, ileal morphology and nutrient transport in a murine model.

Undernutrition represents a major public health challenge for middle- and low-income countries. This study aimed to evaluate whether a multideficient Northeast Brazil regional basic diet (RBD) induces acute morphological and functional changes in the ileum of mice. Swiss mice (∼25 g) were allocated into two groups: i) control mice were fed a standard diet and II) undernourished mice were fed the RBD. After 7 days, mice were killed and the ileum collected for evaluation of electrophysiological parameters (Ussing chambers), transcription (RT-qPCR) and protein expression (western blotting) of intestinal transporters and tight junctions. Body weight gain was significantly decreased in the undernourished group, which also showed decreased crypt depth but no alterations in villus height. Electrophysiology measurements showed a reduced basal short circuit current (Isc) in the undernourished group, with no differences in transepithelial resistance. Specific substrate-evoked Isc related to affinity and efficacy (glutamine and alanyl-glutamine) were not different between groups, except for the maximum Isc (efficacy) induced by glucose. Transcription of Sglt1 and Pept1 was significantly higher in the undernourished group, while SN-2 transcription was decreased. No changes were found in transcription of CAT-1 and CFTR, while claudin-2 and occludin transcriptions were significantly increased in the undernourished group. Despite mRNA changes, SGLT-1, PEPT-1, claudin-2 and occludin protein expression showed no difference between groups. These results demonstrate early effects of the RBD on mice, which include reduced body weight and crypt depth in the absence of significant alterations to villus morphology, intestinal transporters and tight junction expression.

Infestation of Brazilian Peridomiciliary Areas by Culicoides (Diptera: Ceratopogonidae) in Humid and Semihumid Climates.

This study investigates Culicoides infestation in peridomestic environments in two villages in Maranhão, one with hot and humid climate and the other with semihumid climate. We evaluated the composition, richness, abundance, and seasonality of species. We captured insects using CDC light traps installed in animal shelters once a month, from 6 pm to 6 am, for 24 mo (May 2012 to April 2014). In this study, 17 species were found. Of these, 10 occurred simultaneously in two areas; six were found only in hot and humid area, while one occurred only in the semihumid area. Species richness was higher in the hot and humid climate (16 species) than in the semihumid (11 species). The rank of abundance was uneven across areas: C. foxi, C. insignis, C. filariferus, C. ignacioi, and C. flavivenula were dominant in the hot and humid area, and C. ignacioi, C. foxi, C. filariferus, C. insignis, and C. boliviensis in the semihumid. Midges were more abundant in the rainy season in both areas. This result reveals a diversified fauna of midges, with variable abundance of rank according to the area, prevailing in the rainy season and in the Amazon area. It also highlights the need for health monitoring in order to contain the infestation by these insects in peridomestic environments, taking into account that some species can be effective vectors of arboviruses in the Amazon and northeastern Maranhão.

Impact of acute undernutrition on growth, ileal morphology and nutrient transport in a murine model

Undernutrition represents a major public health challenge for middle- and low-income countries. This study aimed to evaluate whether a multideficient Northeast Brazil regional basic diet (RBD) induces acute morphological and functional changes in the ileum of mice. Swiss mice (∼25 g) were allocated into two groups: i) control mice were fed a standard diet and II) undernourished mice were fed the RBD. After 7 days, mice were killed and the ileum collected for evaluation of electrophysiological parameters (Ussing chambers), transcription (RT-qPCR) and protein expression (western blotting) of intestinal transporters and tight junctions. Body weight gain was significantly decreased in the undernourished group, which also showed decreased crypt depth but no alterations in villus height. Electrophysiology measurements showed a reduced basal short circuit current (Isc) in the undernourished group, with no differences in transepithelial resistance. Specific substrate-evoked Isc related to affinity and efficacy (glutamine and alanyl-glutamine) were not different between groups, except for the maximum Isc (efficacy) induced by glucose. Transcription of Sglt1 and Pept1 was significantly higher in the undernourished group, while SN-2 transcription was decreased. No changes were found in transcription of CAT-1 and CFTR, while claudin-2 and occludin transcriptions were significantly increased in the undernourished group. Despite mRNA changes, SGLT-1, PEPT-1, claudin-2 and occludin protein expression showed no difference between groups. These results demonstrate early effects of the RBD on mice, which include reduced body weight and crypt depth in the absence of significant alterations to villus morphology, intestinal transporters and tight junction expression.

Alanyl-glutamine attenuates 5-fluorouracil-induced intestinal mucositis in apolipoprotein E-deficient mice

Apolipoprotein E (APOE=gene, apoE=protein) is a known factor regulating the inflammatory response that may have regenerative effects during tissue recovery from injury. We investigated whether apoE deficiency reduces the healing effect of alanyl-glutamine (Ala-Gln) treatment, a recognized gut-trophic nutrient, during tissue recovery after 5-FU-induced intestinal mucositis. APOE-knockout (APOE-/-) and wild-type (APOE+/+) C57BL6J male and female mice (N=86) were given either Ala-Gln (100 mM) or phosphate buffered saline (PBS) by gavage 3 days before and 5 days after a 5-fluorouracil (5-FU) challenge (450 mg/kg, via intraperitoneal injection). Mouse body weight was monitored daily. The 5-FU cytotoxic effect was evaluated by leukometry. Intestinal villus height, villus/crypt ratio, and villin expression were monitored to assess recovery of the intestinal absorptive surface area. Crypt length, mitotic, apoptotic, and necrotic crypt indexes, and quantitative real-time PCR for insulin-like growth factor-1 (IGF-1) and B-cell lymphoma 2 (Bcl-2) intestinal mRNA transcripts were used to evaluate intestinal epithelial cell turnover. 5-FU challenge caused significant weight loss and leukopenia (P<0.001) in both mouse strains, which was not improved by Ala-Gln. Villus blunting, crypt hyperplasia, and reduced villus/crypt ratio (P<0.05) were found in all 5-FU-challenged mice but not in PBS controls. Ala-Gln improved villus/crypt ratio, crypt length and mitotic index in all challenged mice, compared with PBS controls. Ala-Gln improved villus height only in APOE-/- mice. Crypt cell apoptosis and necrotic scores were increased in all mice challenged by 5-FU, compared with untreated controls. Those scores were significantly lower in Ala-Gln-treated APOE+/+ mice than in controls. Bcl-2 and IGF-1 mRNA transcripts were reduced only in the APOE-/--challenged mice. Altogether our findings suggest APOE-independent Ala-Gln regenerative effects after 5-FU challenge.

Alanyl-glutamine attenuates 5-fluorouracil-induced intestinal mucositis in apolipoprotein E-deficient mice.

Apolipoprotein E (APOE=gene, apoE=protein) is a known factor regulating the inflammatory response that may have regenerative effects during tissue recovery from injury. We investigated whether apoE deficiency reduces the healing effect of alanyl-glutamine (Ala-Gln) treatment, a recognized gut-trophic nutrient, during tissue recovery after 5-FU-induced intestinal mucositis. APOE-knockout (APOE-/-) and wild-type (APOE+/+) C57BL6J male and female mice (N=86) were given either Ala-Gln (100 mM) or phosphate buffered saline (PBS) by gavage 3 days before and 5 days after a 5-fluorouracil (5-FU) challenge (450 mg/kg, via intraperitoneal injection). Mouse body weight was monitored daily. The 5-FU cytotoxic effect was evaluated by leukometry. Intestinal villus height, villus/crypt ratio, and villin expression were monitored to assess recovery of the intestinal absorptive surface area. Crypt length, mitotic, apoptotic, and necrotic crypt indexes, and quantitative real-time PCR for insulin-like growth factor-1 (IGF-1) and B-cell lymphoma 2 (Bcl-2) intestinal mRNA transcripts were used to evaluate intestinal epithelial cell turnover. 5-FU challenge caused significant weight loss and leukopenia (P<0.001) in both mouse strains, which was not improved by Ala-Gln. Villus blunting, crypt hyperplasia, and reduced villus/crypt ratio (P<0.05) were found in all 5-FU-challenged mice but not in PBS controls. Ala-Gln improved villus/crypt ratio, crypt length and mitotic index in all challenged mice, compared with PBS controls. Ala-Gln improved villus height only in APOE-/- mice. Crypt cell apoptosis and necrotic scores were increased in all mice challenged by 5-FU, compared with untreated controls. Those scores were significantly lower in Ala-Gln-treated APOE+/+ mice than in controls. Bcl-2 and IGF-1 mRNA transcripts were reduced only in the APOE-/- -challenged mice. Altogether our findings suggest APOE-independent Ala-Gln regenerative effects after 5-FU challenge.

Sensory and inflammatory colonic changes induced by vincristine in distinct rat models of colitis.

Preclinical and clinical studies show that gastrointestinal (GI) inflammation can evoke sensory changes occasionally far from the original inflammatory site. Animal models of colitis with either trinitrobenzenesulphonic acid (TNBS) or mustard oil (MO) produce distinct patterns of somatic and visceral sensory changes. We evaluated the effects of four doses of i.v. vincristine 150 µg kg(-1) (total of 600 µg kg(-1) ) treatment on the somatic (thermal nociceptive threshold) and colonic (morphological) changes induced by TNBS or MO in rats. TNBS and MO groups were further submitted to vincristine or saline pretreatments. TNBS induced somatic hypersensitivity, while MO induced somatic hyposensitivity (P < 0.05) when compared to the saline and ethanol control groups. Vincristine per se induced somatic hypersensitivity (P < 0.05). This effect was enhanced by TNBS and reversed by MO treatments. Although vincristine increased the colitis area (colonic weight length(-1) ratio) and the Morris' score in TNBS-treated rats, it did not alter the colitis area and even lowered the Morris' score in MO-treated rats. Compared to the saline (control) group, vincristine did not alter the colonic microscopic pattern. However, such lesions scores are higher (P < 0.05) in colitis groups induced by TNBS and MO, pretreated or not with vincristine. In conclusion, the somatic changes induced by different models of experimental colitis are diverse and modulated differently by vincristine.

Bothrops jararacussu snake venom-induces a local inflammatory response in a prostanoid- and neutrophil-dependent manner.

Local tissue reactions provoked by Bothrops venoms are characterized by edema, hemorrhage, pain, and inflammation; however, the mechanisms of tissue damage vary depending upon the species of snake. Here, we investigated the mechanisms involved in the local inflammatory response induced by the Bothrops jararacussu venom (BjcuV). Female Swiss mice were injected with either saline, BjcuV (0.125-8 µg/paw) or loratadine (an H1 receptor antagonist), compound 48/80 (for mast cell depletion), capsaicin (for C-fiber desensitization), infliximab (an anti-TNF-α antibody), indomethacin (a non-specific COX inhibitor), celecoxib (a selective COX-2 inhibitor) or fucoidan (a P- and L-selectins modulator) given before BjcuV injection. Paw edema was measured by plethysmography. In addition, paw tissues were collected for the measurement of myeloperoxidase activity, TNF-α and IL-1 levels, and COX-2 immunoexpression. The direct chemotactic effect of BjcuV and the in vitro calcium dynamic in neutrophils were also investigated. BjcuV caused an edematogenic response with increased local production of TNF-α and IL-1ß as well as COX-2 expression. Both edema and neutrophil migration were prevented by pretreatment with indomethacin, celecoxib or fucoidan. Furthermore, BjcuV induced a direct in vitro neutrophil chemotaxis by increasing intracellular calcium. Therefore, BjcuV induces an early onset edema dependent upon prostanoid production and neutrophil migration.

Tephrosia toxicaria†Pers. reduces temporomandibular joint inflammatory hypernociception: the involvement of the HO-1 pathway.

BACKGROUND: We investigated both the efficacy and the sub-chronic toxicity of Tephrosia toxicaria Pers. in the zymosan-induced temporomandibular joint (TMJ) inflammatory hypernociception in rats evaluating the possible role of heme oxygenase-1 (HO-1). METHODS: Rats were pretreated with T. toxicaria (0.2, 2.0 or 20 mg/kg) 60 min before the intra-articular injection of zymosan (2 mg, 40 µL) in the left TMJ. In another series of experiments, rats were treated with ZnPP-IX (3 mg/kg), a specific HO-1 inhibitor, before T. toxicaria (20 mg/kg). Von Frey test was used to evaluate inflammatory hypernociception (g) 4 h after zymosan injection. Six hours after zymosan injection, the synovial lavage was collected for total cell count and myeloperoxidase (MPO) activity, and joint tissue for histopathological analysis and immunohistochemistry for HO-1. To evaluate the sub-chronic toxicity, mice received T. toxicaria (20 mg/kg) or saline once a day for 14 days to analyse body mass, organ weight and biochemical parameters. RESULTS: T. toxicaria partially reversed the zymosan-induced head withdrawal threshold, the number of cells and the MPO activity. T. toxicaria reduced the inflammatory cell influx in the synovial membrane. TMJ immunohistochemical analyses treated with T. toxicaria showed increased HO-1 expression. These effects of T. toxicaria were not observed in the presence of ZnPP-IX. T. toxicaria treatment for 14 days did not show significant signs of toxicity when administrated to mice. CONCLUSIONS: T. toxicaria did not produce any signs of toxicity and effectively decreased zymosan-induced TMJ inflammatory hypernociception dependent, at least in part, upon the HO-1 pathway integrity.

Targeted inhibition of IL-18 attenuates irinotecan-induced intestinal mucositis in mice.

BACKGROUND AND PURPOSE: Intestinal mucositis is a common side-effect of irinotecan-based cancer chemotherapy regimens. This mucositis is associated with cytokine activation and NO synthesis. Production of IL-18 is up-regulated in patients suffering from inflammatory bowel disease. Therefore, we have investigated the role of IL-18 in the pathogenesis of irinotecan-induced intestinal mucositis. EXPERIMENTAL APPROACH: Wild type (WT), IL-18 or caspase-1 knockout mice were treated with either saline or irinotecan (60 mg·kg⁻¹ per 4 days, i.p.) or the IL-18 binding protein (IL-18bp, 10 mg·kg⁻¹) before irinotecan. On day 5, diarrhoea was monitored and proximal intestinal strips were obtained for histopathology, in vitro gut contractility, myeloperoxidase (MPO) and inducible NOS (iNOS) activity, and detection of IL-18 expression. KEY RESULTS: Irinotecan induced severe diarrhoea accompanied by intestinal injury (villi shortening and increased crypt depth). Additionally, irinotecan treatment increased MPO and iNOS activity, iNOS immunostaining and IL-18 expression in WT mice compared with saline treatment. The IL-18 production was associated with macrophages. In vitro, intestinal smooth muscle strips were hyperresponsive to ACh after irinotecan treatment. Increases in MPO and iNOS activity, intestinal contractility and diarrhoea were prevented in caspase-1 knockout and IL-18 knockout mice, and in IL-18bp-treated WT mice. Furthermore, the Survival of irinotecan-treated mice was increased and iNOS immunoexpression and IL-18 production prevented in IL-18 knockout mice. CONCLUSIONS AND IMPLICATIONS: Targeting IL-18 function may be a promising therapeutic approach to decreasing the severity of intestinal mucositis during irinotecan treatment regimens.

Blockade of TRPA1 with HC-030031 attenuates visceral nociception by a mechanism independent of inflammatory resident cells, nitric oxide and the opioid system.

BACKGROUND: Some studies have shown a somatic nociceptive response due to the activation of transient receptor potential A1 channels (TRPA1), which is modulated by the TRPA1 antagonist HC-030031. However, a few studies report the role of TRPA1 in visceral pain. Therefore, we investigated the participation of TRPA1 in visceral nociception and the involvement of nitric oxide, the opioid system and resident cells in the modulation of these channels. METHODS: Mice were treated with vehicle or HC-030031 (18.75-300 mg/kg) before ifosfamide (400 mg/kg), 0.75% mustard oil (50 µL/colon), acetic acid 0.6% (10 mL/kg), zymosan (1 mg/cavity) or misoprostol (1 µg/cavity) injection. Visceral nociception was assessed through the electronic von Frey test or the writhing response. Ifosfamide-administered mice were euthanized for bladder analysis. The involvement of nitric oxide and the opioid system were investigated in mice injected with ifosfamide and mustard oil, respectively. The participation of resident peritoneal cells in acetic acid-, zymosan- or misoprostol-induced nociception was also evaluated. RESULTS: HC-030031 failed to protect animals against ifosfamide-induced bladder injury (p > 0.05). However, a marked antinociceptive effect against ifosfamide, mustard oil, acetic acid, zymosan and misoprostol was observed (p < 0.05). Neither L-arginine (600 mg/kg) nor naloxone (2 mg/kg) could reverse the antinociceptive effect of HC-030031. The reduction of the peritoneal cell population inhibited the acetic acid and zymosan-related writhes without interfering with the misoprostol effect. CONCLUSIONS: Our findings suggest that the blockade of TRPA1 attenuates visceral nociception by a mechanism independent of the modulation of resident cells, nitric oxide and opioid pathways.

Long-term outcome of patients followed by nephrologists after an acute tubular necrosis episode.

Aims of our study were to describe the long-term survival in patients surviving an acute tubular necrosis (ATN) episode and determine factors associated with late mortality. We performed a prospective cohort study that evaluated the long-term outcome of 212 patients surviving an ATN episode. Mortality at the end of followup was 24.5%, and the probability of these patients being alive 5 years after discharge was 55%. During the followup, 4.7% of patients needed chronic dialysis. Univariate analysis showed that previous CKD (P = 0.0079), cardiovascular disease (P = 0.019), age greater than 60 years (P < 0.0001), and higher SCr baseline (P = 0.001), after 12 months (P = 0.0015) and 36 months (P = 0.004), were predictors of long-term mortality. In multivariate analysis, older age (HR = 6.4, CI 95% = 1.2-34.5, P = 0.02) and higher SCr after 12 months (HR = 2.1, 95% CI 95% = 1.14-4.1, P = 0.017) were identified as risk factors associated with late mortality. In conclusion, 55% of patients surviving an ATN episode were still alive, and less than 5% required chronic dialysis 60 months later; older age and increased Scr after 12 months were identified as risk factors associated with late death.

Role of the haem oxygenase/carbon monoxide pathway in Clostridium difficile toxin A-induced enteritis in mice.

Clostridium difficile is the major cause of antibiotic-associated colitis, a disease with significant morbidity and mortality. This study investigated the role of the haem oxygenase-1 (HO-1)/carbon monoxide (CO) pathway in C. difficile toxin A-induced enteritis in mice. The HO substrate haemin, zinc protoporphyrin IX (ZnPP IX), a specific HO-1 inhibitor, dimanganese decacarbonyl (DMDC), a CO donor, or an equivalent volume of their respective vehicles were injected subcutaneously 30 min prior to local challenge with toxin A (25 or 50 µg per ileal loop) or PBS. Intestinal ileal loop weight/length ratios were calculated 3 h later. Ileal tissues were collected for histological analysis and measurement of myeloperoxidase (MPO) activity, tumour necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1ß) production by ELISA and immunohistochemistry for HO-1. Treatment of mice subjected to C. difficile toxin A (TcdA) with haemin or DMDC prevented oedema, mucosal disruption and neutrophil infiltration observed in histological analysis. It also decreased TcdA-induced MPO activity and TNF-α or IL-1ß production. In contrast, the specific HO-1 inhibitor (ZnPP IX) exacerbated all these evaluated parameters. TcdA increased HO-1 expression as seen by immunohistochemistry. These results suggest that the HO-1/CO pathway exerts a protective role in TcdA-induced enteritis and that its pharmacological modulation might be important for the management of C. difficile-associated disease.

In vivo and in vitro anti-inflammatory and anti-nociceptive activities of lovastatin in rodents

Statins are among the most prescribed drugs in recent clinical practice. They are also known for their pleiotropic actions, which are independent of their lipid-lowering properties. The effect of lovastatin was investigated against carrageenan-induced paw edema in male Wistar rats (200-250 g) and on leukocyte migration, as measured by carrageenan-induced peritonitis in male Swiss mice (20-25 g), which are models of acute inflammation. Lovastatin (administered 1 h prior to carrageenan), at oral doses of 2, 5, and 10 mg/kg, markedly attenuated paw edema formation in rats at the 4th hour after carrageenan injection (25, 43, and 37 percent inhibition, respectively). Inhibitions of 20, 45 and 80 percent were observed in the leukocyte migration, as evaluated by carrageenan-induced peritonitis in mice with lovastatin doses of 0.5, 1 and 5 mg/kg, as compared to controls. Furthermore, lovastatin (administered 1 h before initiation) reduced the nociceptive effect of the formalin test in mice, at both phases, at doses of 2, 5, and 10 mg/kg: first phase (51, 65, and 70 percent, respectively) and second phase (73, 57, and 66 percent inhibition of licking time, respectively). The anti-nociceptive activity of lovastatin was inhibited by naloxone (3 mg/kg, sc). Lovastatin (0.01, 0.1, and 1 µg/mL) inhibited by 23, 79, and 86 percent, respectively, the release of myeloperoxidase from human neutrophils. Leukocyte (predominantly neutrophils) infiltration was almost completely reduced by lovastatin treatment, as observed in the model of acute paw edema with hematoxylin and eosin staining. In addition, lovastatin decreased the number of cells expressing tumor necrosis factor-α (TNF-α) and the inducible form of nitric oxide synthase (iNOS) activity. Therefore, the alterations in leukocyte activity and cytokine release could contribute to the anti-inflammatory activity of lovastatin.

In vivo and in vitro anti-inflammatory and anti-nociceptive activities of lovastatin in rodents.

Statins are among the most prescribed drugs in recent clinical practice. They are also known for their pleiotropic actions, which are independent of their lipid-lowering properties. The effect of lovastatin was investigated against carrageenan-induced paw edema in male Wistar rats (200-250 g) and on leukocyte migration, as measured by carrageenan-induced peritonitis in male Swiss mice (20-25 g), which are models of acute inflammation. Lovastatin (administered 1 h prior to carrageenan), at oral doses of 2, 5, and 10 mg/kg, markedly attenuated paw edema formation in rats at the 4th hour after carrageenan injection (25, 43, and 37% inhibition, respectively). Inhibitions of 20, 45 and 80% were observed in the leukocyte migration, as evaluated by carrageenan-induced peritonitis in mice with lovastatin doses of 0.5, 1 and 5 mg/kg, as compared to controls. Furthermore, lovastatin (administered 1 h before initiation) reduced the nociceptive effect of the formalin test in mice, at both phases, at doses of 2, 5, and 10 mg/kg: first phase (51, 65, and 70%, respectively) and second phase (73, 57, and 66% inhibition of licking time, respectively). The anti-nociceptive activity of lovastatin was inhibited by naloxone (3 mg/kg, sc). Lovastatin (0.01, 0.1, and 1 µg/mL) inhibited by 23, 79, and 86%, respectively, the release of myeloperoxidase from human neutrophils. Leukocyte (predominantly neutrophils) infiltration was almost completely reduced by lovastatin treatment, as observed in the model of acute paw edema with hematoxylin and eosin staining. In addition, lovastatin decreased the number of cells expressing tumor necrosis factor-α (TNF-α) and the inducible form of nitric oxide synthase (iNOS) activity. Therefore, the alterations in leukocyte activity and cytokine release could contribute to the anti-inflammatory activity of lovastatin.