Anti-inflammatory latex proteins of the medicinal plant Calotropis procera: a promising alternative for oral mucositis treatment.

OBJECTIVE AND DESIGN: Oral mucositis (OM) is an intense inflammatory reaction progressing to tissue damage and ulceration. The medicinal uses of Calotropis procera are supported by anti-inflammatory capacity. PII-IAA, a highly homogenous cocktail of laticifer proteins (LP) prepared from the latex of C. procera, with recognized pharmacological properties was tested to treat OM. MATERIALS AND SUBJECTS: Male Golden Sirius hamsters were used in all treatments. TREATMENT: The latex protein samples were injected i.p. (5 mg/Kg) 24 h before mucositis induction (mechanical trauma) and 24 h later. METHODS: Histology, cytokine measurements [ELISA], and macroscopic evaluation [scores] were performed. RESULTS: PII-IAA eliminated OM, accompanied by total disappearance of myeloperoxidase activity and release of IL-1b, as well as reduced TNF-a. Oxidative stress was relieved by PII-IAA treatment, as revealed by MDA and GSH measurements. PII-IAA also reduced the expression of adhesion molecules (ICAM-1) and Iba-1, two important markers of inflammation, indicating modulatory effects. Histological analyses of the cheek epithelium revealed greater deposition of type I collagen fibers in animals given PII-IAA compared with the control group. This performance was only reached when LPPII was treated with iodoacetamide (IAA), an irreversible inhibitor of proteolytic activity of cysteine proteases. The endogenous proteolytic activity of LPPII induced adverse effects in animals. Candidate proteins involved in the phytomodulatory activity are proposed. CONCLUSIONS: Therapy was successful in treating OM with the laticifer protein fraction, containing peptidases and osmotin, from Calotropis procera. The effective candidate from the latex proteins for therapeutic use is PII-IAA.

AMPK activation promotes gastroprotection through mutual interaction with the gaseous mediators H2S, NO, and CO.

Activation of 5' adenosine monophosphate-activated protein kinase (AMPK) stimulates production of the gaseous mediators nitric oxide (NO) and carbon monoxide (CO), which are involved in mucosal defense and gastroprotection. As AMPK itself has gastroprotective effects against several gastric ulcer etiologies, in the present study, we aimed to elucidate whether AMPK may also prevent ethanol-induced injury and play a key role in the associated gastroprotection mediated by hydrogen sulfide (H2S), NO, and CO. Mice were pretreated with AICAR (20 mg/kg, an AMPK activator) alone or with 50% ethanol. Other groups were pretreated with respective gaseous mediator inhibitors PAG, l-NAME, or ZnPP IX 30 min prior to AICAR, or with gaseous mediator donors NaHS, Lawesson's reagent and l-cysteine (H2S), SNP, l-Arginine (NO), Hemin, or CORM-2 (CO) 30 min prior to ethanol with or without compound C (10 mg/kg, a non-selective AMPK inhibitor). H2S, nitrate/nitrite (NO3-/NO2-), bilirubin levels, GSH and MDA concentration were evaluated in the gastric mucosa. The gastric mucosa was also collected for histopathological analysis and AMPK expression assessment by immunohistochemistry. Pretreatment with AICAR attenuated the ethanol-induced injury and increased H2S and bilirubin levels but not NO3-/NO2- levels in the gastric mucosa. In addition, inhibition of H2S, NO, or CO synthesis exacerbated the ethanol-induced gastric damage and inhibited the gastroprotection by AICAR. Pretreatment with compound C reversed the gastroprotective effect of NaHS, Lawesson's reagent, l-cysteine, SNP, l-Arginine, CORM-2, or Hemin. Compound C also reversed the effect of NaHS on H2S production, SNP on NO3-/NO2- levels, and Hemin on bilirubin levels. Immunohistochemistry revealed that AMPK is present at basal levels mainly in the gastric mucosa cells, and was increased by pretreatment with NaHS, SNP, and CORM-2. In conclusion, our findings indicate that AMPK activation exerts gastroprotection against ethanol-induced gastric damage and mutually interacts with H2S, NO, or CO to facilitate this process.

Apoptosis in human liver carcinoma caused by gold nanoparticles in combination with carvedilol is mediated via modulation of MAPK/Akt/mTOR pathway and EGFR/FAAD proteins.

In cancers, apoptosis signaling pathways and cell survival and growth pathways responsible for resistance to conventional treatments, such as Pi3K/Akt/mTOR and mitogen-activated protein kinase (MAPK) become dysregulated. Recently, alternative treatments to promote tumor cell death have become important. The present study reports on the antitumor and cytoprotective action of gold nanoparticles (GNPs) and carvedilol in combination and in isolated application. Apoptosis was analyzed by FITC/propidium iodide staining flow cytometry; caspase-3, caspase-8, Bcl-2 and MAPK/ERK activity by immunofluorescence microscopy; gene expression of proteins related to cell death as Akt, mTOR, EGFR, MDR1, survivin, FADD and Apaf, by the real-time PCR; and western blot analysis for MAPK/ERK, Akt and mTOR. Oxidative stress evaluation was performed by reduced glutathione (GSH) and malondialdehyde (MDA) levels. Intracellular GNPs targets were identified by transmission electron microscopy. After exposure to a combination of GNPs (6.25 µg/ml) and carvedilol (3 µM), death as promoted by apoptosis was detected using flow cytometry, for expression of pro-apoptotic proteins FADD, caspase-3, caspase-8 and sub-regulation of anti-apoptotic MAPK/ERK, Akt, mTOR, EGFR and MDR1 resistance. Non-tumor cell cytoprotection with GSH elevation and MDA reduction levels was detected. GNPs were identified within the cell near to the nucleus when combined with carvedilol. The combination of GNP and carvedilol promoted downregulation of anti-apoptotic and drug resistance genes, over-regulation of pro-apoptotic proteins in tumor cells, as well as cytoprotection of non-tumor cells with reduction of apoptosis and oxidative stress.

Carvacryl acetate, a novel semisynthetic monoterpene ester, binds to the TRPA1 receptor and is effective in attenuating irinotecan-induced intestinal mucositis in mice.

OBJECTIVES: We aimed to determine whether carvacryl acetate acts as a TRPA1 receptor agonist and its effects against irinotecan (CPT-11) induced intestinal mucositis in mice. METHODS: TRPA1 structure was obtained from a protein databank, and the 3D structure of carvacryl acetate was determined. Appropriate binding conformations were discovered via automatic docking simulations. To determine the effect of carvacryl acetate in vivo, mice were treated with either DMSO 2%, CPT-11, carvacryl acetate followed by CPT-11, or HC-030031, a TRPA1 antagonist, followed by carvacryl acetate. Jejunum samples were taken and structural, inflammatory and antioxidant parameters were studied. KEY FINDINGS: Eight amino acids residues in TRPA1 established stable interactions with carvacryl acetate, which led to pharmacological efficacy against CPT-11-induced intestinal mucositis via reduction of both neutropenia and bacteremia, increase in villi height and crypt depth, decrease in pro-inflammatory cytokines (interleukin-1ß, keratinocyte chemoattractant and tumour necrosis factor-α) and decrease in malondialdehyde and nitric oxide metabolite levels in the jejunum. CONCLUSIONS: Carvacryl acetate is a promising anti-inflammatory and antioxidant agent, a fact confirmed through observations of its interactions with TRPA1 in CPT-11-induced intestinal mucositis in mice.

Wound healing modulation by a latex protein-containing polyvinyl alcohol biomembrane.

In a previous study, we performed the chemical characterization of a polyvinyl alcohol (PVA) membrane supplemented with latex proteins (LP) displaying wound healing activity, and its efficacy as a delivery system was demonstrated. Here, we report on aspects of the mechanism underlying the performance of the PVA-latex protein biomembrane on wound healing. LP-PVA, but not PVA, induced more intense leukocyte (neutrophil) migration and mast cell degranulation during the inflammatory phase of the cicatricial process. Likewise, LP-PVA induced an increase in key markers and mediators of the inflammatory response (myeloperoxidase activity, nitric oxide, TNF, and IL-1ß). These results demonstrated that LP-PVA significantly accelerates the early phase of the inflammatory process by upregulating cytokine release. This remarkable effect improves the subsequent phases of the healing process. The polyvinyl alcohol membrane was fully absorbed as an inert support while LP was shown to be active. It is therefore concluded that the LP-PVA is a suitable bioresource for biomedical engineering.

Pentoxifylline decreases glycemia levels and TNF-alpha, iNOS and COX-2 expressions in diabetic rat pancreas.

Pentoxifylline (PTX), a methyl xanthine derivative, is a phosphodiesterase inhibitor with anti-inflammatory and renoprotective effects in diabetic patients, among other properties. We studied PTX actions and mechanisms in reducing blood biochemical parameters, in diabetic rats. For diabetes induction, alloxan was intravenously administered to male Wistar rats. One group was left untreated and the other ones treated with PTX (25, 50 and 100 mg/kg), glibenclamide or metformin, as references. Forty-eight hours later and after 1-week to 3-month treatments, blood was collected for determination of glycemia, triglycerides, cholesterol, transaminases, fructosamine and glycated hemoglobin. Afterwards, the animals were euthanized and pancreas, liver and kidney processed for histological analyses and immunohistochemistry assays for TNF-alpha, iNOS and COX-2. The results showed that PTX decreased glycemia and also triglyceride levels, starting 1 week after treatments, as compared to the same group before treatments. Glycemia values were brought towards normality, after 1-month treatment. PTX hypoglycemic effects were potentiated by glibenclamide but not by metformin. It also decreased fructosamine and glycated hemoglobin. Some histological and immunohistochemical alterations for TNF-alpha, iNOS and COX-2 in the diabetic pancreas were also reversed by PTX. We conclude that PTX acts similarly to glibenclamide, and its hypoglycemic actions are, partly, a consequence of ATP-sensitive K(+) channels inhibition. In addition, by its anti-inflammatory and antioxidant properties, PTX may be a therapeutic alternative for the treatment of diabetes and its complications.

Piperine decreases pilocarpine-induced convulsions by GABAergic mechanisms.

Piperine, an alkaloid present in the Piper genus, was shown to have an anticonvulsant activity, evaluated by the pilocarpine-induced model, in mice. Pilocarpine (350mg/kg, i.p.) was administered 30min after piperine (2.5, 5, 10 and 20mg/kg, i.p.) which significantly increased latencies to 1st convulsion and to death, and percentage of survivals. These parameters were also increased in the pilocarpine groups pretreated with atropine plus piperine (10 and 2.5mg/kg, respectively), as related to the pilocarpine group. However, they were not altered in the pilocarpine groups pretreated with memantine (a NMDA-type glutamate receptors blocker, 2mg/kg, p.o.) or nimodipine (a calcium channel blocker, 10mg/kg, p.o.), both associated with piperine (1 or 2.5mg/kg), as compared to the piperine plus pilocarpine group. Moreover, the pilocarpine group pretreated with diazepam (which binds to the GABAA receptor, 0.2 and 0.5mg/kg, i.p.) plus piperine (1 and 2.5mg/kg) significantly increased latency to the 1st convulsion, as related to the pilocarpine group, suggesting that the GABAergic system is involved with the piperine action. Furthermore, the piperine effect was blocked by flumazenil (2mg/kg, i.p.), a benzodiazepine antagonist. Untreated P350 animals showed decreased striatal DA and increased DOPAC and HVA levels that were not affected in the piperine plus pilocarpine groups. Piperine increased striatal levels of GABA, glycine and taurine, and reversed pilocarpine-induced increases in nitrite contents in sera and brain. Hippocampi from the untreated pilocarpine group showed an increased number of TNF-α immunostained cells in all areas, as opposed to the pilocarpine group pretreated with piperine. Taken together, piperine anticonvulsant effects are the result of its anti-inflammatory and antioxidant actions, as well as TNF-α reduction. In addition, piperine effects on inhibitory amino acids and on the GABAergic system may certainly contribute to the drug anticonvulsant activity.

The microalga Spirulina platensis presents anti-inflammatory action as well as hypoglycemic and hypolipidemic properties in diabetic rats.

Spirulina platensis (Spi) is a microalga presenting high contents of proteins, γ-linolenic acid, vitamins and minerals, and showing many biological activities. It is a promising drug for the treatment of diseases including diabetes. The objectives of this work were to study Spi effects on alloxan-induced diabetic rats, and associate this to its anti-inflammatory activity. The treatment with Spi (25, 50 or 100 mg/kg, p.o.) started 48 h after the alloxan injection, continuing for 5 or 10 days. Biochemical parameters were measured in sera of treated and untreated animals. The anti-inflammatory activity of Spi was assessed by the formalin test and carrageenan-induced paw edema in mice. Immunostainings for TNF-alpha were carried out in the carrageenan-induced paw edema in rats, before and after the Spi treatment, and its effect on the release of myeloperoxidase from human neutrophils was also determined. Spi decreased glycemia as well as triglyceride and total cholesterol levels of diabetic rats. Levels of urea and creatinine were also reduced, while liver transaminases were unaltered. Spi also decreased dose-dependently the 1st (neurogenic) and mainly the 2nd phase (inflammatory) of the formalin test, as well as the carrageenan-induced paw edema in mice. The anti-inflammatory effect of Spi was further confirmed by decreases in TNF-alpha immunostaining in the inflamed paw and in the myeloperoxidase release from human neutrophils. The results showed that the anti-diabetic effect of S. platensis is already manifested after a 5-day treatment. Additionally, considering the relationship between diabetes and inflammation, the microalga anti-inflammatory action may also be involved.

Protein fraction of Calotropis procera latex protects against 5-fluorouracil-induced oral mucositis associated with downregulation of pivotal pro-inflammatory mediators.

Oral mucositis is an important dose-limiting and costly side effect of cancer chemotherapy. Soluble proteins obtained of the latex of Calotropis procera have been extensively characterized as anti-inflammatory in different experimentally induced inflammatory conditions, including arthritis and sepsis. In this study, the phytomodulatory laticifer proteins (LP) were challenged to regress the inflammatory events associated with 5-fluorouracil-induced oral mucositis. We also evaluated the expression of pro-inflammatory cytokines and inducible enzymes, such as cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). Oral mucositis was induced in hamsters by two injections of 5-fluorouracil (5-FU; 60 and 40 mg/kg, i.p., on experimental days 1 and 2, respectively). LP (5 mg/kg, i.p.) was injected 24 h before and 24 h after mechanical trauma of the cheek pouches. A normal control group received only saline. On day 10, the animals were sacrificed, and the cheek pouches were excised for macroscopic and histopathological analysis, myeloperoxidase activity measurement, and immunohistochemical assessment of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), iNOS, and COX-2. LP significantly inhibited macroscopic histopathological scores and myeloperoxidase activity compared with the 5-FU control group. 5-Fluorouracil also induced marked immunostaining of TNF-α, IL-1ß, iNOS, and COX-2 on inflamed conjunctive and epithelial tissue compared with the normal control group. Such damage was significantly inhibited (p < 0.05) by LP treatment compared with the 5-FU group. These findings demonstrate an anti-inflammatory effect of LP on 5-FU-induced oral mucositis. The protective mechanism appears to involve inhibition of the expression of iNOS, COX-2, TNF-α, and IL-1ß.

Inflammation induced by phytomodulatory proteins from the latex of Calotropis procera (Asclepiadaceae) protects against Salmonella infection in a murine model of typhoid fever.

OBJECTIVE AND DESIGN: Laticifer proteins (LP) of Calotropis procera were fractionated by ion-exchange chromatography, and the influence of a sub-fraction (LP(PI)) on the inflammatory response of Swiss mice challenged by Salmonella enterica Ser. Typhimurium was investigated. METHODS: Mice (n = 10) received LP(PI) (30 or 60 mg/kg) in a single inoculum by the intraperitoneal route 24 h before infection. To investigate the relevance of the proteolytic activity, three additional groups were included: the first one received heat-treated LP (30 mg/kg-30 min at 100 °C), the second received LP (30 mg/kg) inactivated by iodoacetamide, and a control group received only phosphate-buffered saline (PBS). RESULTS: The survival rate reached 100 % in mice treated with LP(PI) and was also observed with the other treatment, whereas the PBS group died 1-3 days after infection. The neutrophil infiltration into the peritoneal cavity of pretreated mice was enhanced and accompanied by high bacterial clearance from the bloodstream. Tumor necrosis factor-alpha mRNA transcripts, but not interferon-gamma, were detected early in spleen cells of pretreated mice after infection; however, the nitric oxide contents in the bloodstream were decreased in comparison to the PBS group. CONCLUSIONS: The inflammatory stimulus of C. procera proteins increased phagocytosis and balanced the nitric oxide release in the bloodstream, preventing septic shock induced by Salmonella infection.

Involvement of nitric oxide on the pathogenesis of irinotecan-induced intestinal mucositis: role of cytokines on inducible nitric oxide synthase activation.

PURPOSE: Intestinal mucositis and the closely associated diarrhea are common costly side effects of irinotecan. Cytokine modulators, such as thalidomide and pentoxifylline, are found capable of attenuating intestinal mucositis progression. Nitric oxide (NO) seems to be a key mediator of the antineoplastic drug toxicity. The aim of this study was to investigate the role of NO on the pathogenesis of intestinal mucositis, as well as the participation of cytokines upon inducible nitric oxide synthase (iNOS) expression in irinotecan-induced intestinal mucositis. METHODS: iNOS-knockout (iNOS(-/-)) and C57BL/6 (WT, wild type) animals (n = 5-6) were given either saline or irinotecan (60 mg/kg i.p for 4 days), with or without pretreatment with aminoguanidine (50 mg/kg s.c.), thalidomide (60 mg/kg s.c), infliximab (5 mg/kg i.v.), or pentoxifylline (1.7 mg/kg s.c). On day 5, diarrhea was assessed, and following euthanasia, proximal intestinal samples were obtained for myeloperoxidase (MPO) and iNOS activity, morphometric analysis, western blot and immunohistochemistry to iNOS, cytokine dosage, and for in vitro evaluation of gut contractility. RESULTS: Irinotecan induced severe diarrhea and intestinal smooth muscle over-contractility, accompanied with histopathological changes. Additionally, increased MPO and iNOS activity and iNOS immunoexpression were found in WT animals treated with irinotecan. The rise in MPO, smooth muscle over-contractility, and diarrhea were abrogated in aminoguanidine-treated and iNOS(-/-) mice. Moreover, through western blot, we verified that infliximab and pentoxifylline significantly inhibited irinotecan-induced iNOS expression. In addition, cytokine concentration was found only partially decreased in irinotecan-treated iNOS(-/-) mice when compared with wild-type animals that were given irinotecan. CONCLUSIONS: This study suggests a role of nitric oxide in the pathogenesis of irinotecan-induced intestinal mucositis and also provides evidence for the participation of cytokines on iNOS induction.

Anti-inflammatory effect of α,ß-amyrin, a triterpene from Protium heptaphyllum, on cerulein-induced acute pancreatitis in mice.

OBJECTIVE: To evaluate the anti-inflammatory effect of α,ß-amyrin, a pentacyclic triterpenoid from Protium heptaphyllum, on cerulein-induced acute pancreatitis in mice. METHODS: Acute pancreatitis was induced in Swiss mice by five intraperitoneal injections of cerulein (50 µg/kg), at 1 h intervals. Mice received α,ß-amyrin (10, 30 and 100 mg/kg), thalidomide (200 mg/kg), or vehicle (3% Tween 80) orally 1 h before and 12 h after the cerulein challenge. The severity of pancreatitis was evaluated 24 h after cerulein by assessing serum pro-inflammatory cytokines and amylase activity, pancreatic myeloperoxidase (MPO), and thiobarbituric acid-reactive substances (TBARS), as well as by histology. RESULTS: α,ß-Amyrin and thalidomide significantly attenuated the cerulein-induced increase in tumor necrosis factor (TNF)-α, interleukin-6, lipase, amylase, MPO, and TBARS. Moreover, α,ß-amyrin greatly suppressed the pancreatic edema, inflammatory cell infiltration, acinar cell necrosis, and expressions of TNFα and inducible nitric oxide synthase. CONCLUSIONS: α,ß-Amyrin ameliorates cerulein-induced acute pancreatitis by acting as an anti-inflammatory and antioxidant agent.

Role of capsaicin-sensitive primary afferent neurons and non-protein sulphydryl groups on gastroprotective effect of amifostine against ethanol-induced gastric damage in rats.

BACKGROUND: Amifostine has been widely tested as a cytoprotective agent against a number of aggressors in different organs. Recently, a gastroprotective effect was observed for this drug in a model of indomethacin-induced gastric injury. Our objective was to investigate the effect of amifostine on ethanol-induced gastric injury and the role played in this mechanism by afferent sensory neurons, non-protein sulfhydryl groups, nitric oxide, ATP-sensitive potassium channels, and cyclooxygenase-2. METHODS: Rats were treated with amifostine (22.5, 45, 90, or 180 mg/kg, PO or SC). After 30 min, the rats received absolute ethanol (5 ml kg(-1), PO). One hour later, gastric damage was quantified with a planimeter. Samples from the stomach were also taken for histopathological assessment and for assays of non-protein sulfhydryl groups. The other groups were pretreated with L-NAME (10 mg kg(-1), IP), glibenclamide (10 mg kg(-1), PO), or celecoxib (10 mg kg(-1), PO). After 30 min, the animals were given amifostine (90 mg kg(-1), PO or SC), followed 30 min later by gavage with absolute ethanol (5 ml kg(-1)). Other rats were desensitized with capsaicin (125 mg kg(-1), SC) 8 days prior to amifostine treatment. RESULTS: Amifostine administration PO and SC significantly and dose-dependently reduced ethanol-induced macroscopic and microscopic gastric damage by restoring glutathione levels in the stomach mucosa. Amifostine-promoted gastroprotection against ethanol-induced stomach injury was reversed by pretreatment with neurotoxic doses of capsaicin, but not by L-NAME, glibenclamide, or celecoxib. CONCLUSIONS: Amifostine protects against ethanol-induced gastric injury by increasing glutathione levels and stimulating the afferent sensory neurons in the stomach.

Role of platelet-activating factor in the pathogenesis of 5-fluorouracil-induced intestinal mucositis in mice.

PURPOSE: Gastrointestinal mucositis is a common side effect of cancer chemotherapy. Platelet-activating factor (PAF) is produced during gut inflammation. There is no evidence that PAF participates in antineoplastic-induced intestinal mucositis. This study evaluated the role of PAF in 5-fluorouracil (5-FU)-induced intestinal mucositis using a pharmacological approach and PAF receptor knockout mice (PAFR(-/-)). METHODS: Wild-type mice or PAFR(-/-) mice were treated with 5-FU (450 mg/kg, i.p.). Other mice were treated with saline or BN52021 (20 mg/kg, s.c.), an antagonist of the PAF receptor, once daily followed by 5-FU administration. After the third day of treatment, animals were sacrificed and tissue samples from the duodenum were removed for morphologic evaluation. In addition, myeloperoxidase activity and the cytokine concentration were measured. RESULTS: 5-FU treatment decreased the duodenal villus height/crypt depth ratio, increased MPO activity, and increased the concentration of TNF-α, IL-1ß and KC in comparison with saline-treated animals. In PAFR(-/-) mice and PAFR antagonist-treated mice, 5-FU-dependent intestinal damage was reduced and a decrease in duodenal villus height/crypt depth ratio was attenuated. However, the 5-FU-dependent increase in duodenum MPO activity was not affected. Without PAFR activation, 5-FU treatment did not increase the TNF-α, IL-1ß and KC concentration. CONCLUSIONS: In conclusion, our study establishes the role of PAFR activation in 5-FU-induced intestinal mucositis. This study implicates treatment with PAFR antagonists as novel therapeutic strategy for this condition.

Gastroprotective effect of heme-oxygenase 1/biliverdin/CO pathway in ethanol-induced gastric damage in mice.

Our objective was to evaluate the role of heme-oxygenase 1 (HO-1)/biliverdin/CO pathway in gastric defense against ethanol-induced gastric damage in mice. Mice were pre-treated with saline, hemin (HO-1 inducer), biliverdin (HO-1 product), dimanganese decacarbonyl (DMDC, CO donor) or zinc protoporphyrin IX (ZnPP IX, HO-1 antagonist). Another group received soluble guanylate cyclase (sGC) inhibitor (ODQ) 30 min before hemin, biliverdin or DMDC. After 30 min, gastric damage was induced by ethanol. After one hour, rats were sacrificed. Gastric lesions were measured using a computer planimetry program, and gastric corpus pieces were assayed for malonylaldehyde (MDA), glutathione (GSH) or bilirubin. HO-1 expression was determined after saline or ethanol administration by polymerase chain reaction (PCR) or immunohistochemistry. Ethanol (25% or 50%) induced gastric damage, increased MDA levels and reduced GSH in the gastric tissue. Ethanol 50% increased HO-1 mRNA transcripts, HO-1 immunoreactivity, and bilirubin concentration in gastric mucosa. Pre-treatment with hemin reduced gastric damage and MDA formation and increased GSH concentration in the gastric mucosa. ZnPP IX amplified the ethanol-induced gastric lesion, increased MDA formation and decreased GSH concentration in gastric mucosa. Biliverdin and DMDC reduced gastric damage and MDA formation and increased GSH concentration in the gastric tissue. ODQ completely abolished the DMDC protective gastric effect. However, effects of hemin or biliverdin did not change with ODQ treatment. Our results suggest that HO-1/biliverdin/CO pathway plays a protective role against ethanol-induced gastric damage through mechanisms that can be dependent (CO) or independent (biliverdin) of sGC activation.

Hydrogen sulfide prevents ethanol-induced gastric damage in mice: role of ATP-sensitive potassium channels and capsaicin-sensitive primary afferent neurons.

The aim of this study was to evaluate the protective effect of hydrogen sulfide (H(2)S) on ethanol-induced gastric lesions in mice and the influence of ATP-sensitive potassium (K(ATP)) channels, capsaicin-sensitive sensory afferent neurons, and transient receptor potential vanilloid (TRPV) 1 receptors on such an effect. Saline and L-cysteine alone or with propargylglycine, sodium hydrogen sulfide (NaHS), or Lawesson's reagent were administrated for testing purposes. For other experiments, mice were pretreated with glibenclamide, neurotoxic doses of capsaicin, or capsazepine. Afterward, mice received L-cysteine, NaHS, or Lawesson's reagent. After 30 min, 50% ethanol was administrated by gavage. After 1 h, mice were sacrificed, and gastric damage was evaluated by macroscopic and microscopic analyses. L-cysteine, NaHS, and Lawesson's reagent treatment prevented ethanol-induced macroscopic and microscopic gastric damage in a dose-dependent manner. Administration of propargylglycine, an inhibitor of endogenous H(2)S synthesis, reversed gastric protection induced by L-cysteine. Glibenclamide reversed L-cysteine, NaHS, or Lawesson's reagent gastroprotective effects against ethanol-induced macroscopic damage in a dose-dependent manner. Chemical ablation of sensory afferent neurons by capsaicin reversed gastroprotective effects of L-cysteine or H(2)S donors (NaHS or Lawesson's reagent) in ethanol-induced macroscopic gastric damage. Likewise, in the presence of the TRPV1 antagonist capsazepine, the gastroprotective effects of L-cysteine, NaHS, or Lawesson's reagent were also abolished. Our results suggest that H(2)S prevents ethanol-induced gastric damage. Although there are many mechanisms through which this effect can occur, our data support the hypothesis that the activation of K(ATP) channels and afferent neurons/TRPV1 receptors is of primary importance.

Adjunctive benefits of systemic etoricoxib in non-surgical treatment of aggressive periodontitis: short-term evaluation.

BACKGROUND: This pilot study assessed the effect of short-duration treatment with etoricoxib as adjuvant therapy to scaling and root planing (SRP) on the clinical and radiographic parameters and prostaglandin E(2) (PGE(2)) levels in aggressive periodontitis. METHODS: Subjects were randomly allocated to test or control treatment (n = 10 in each group) and submitted to SRP and treatment with etoricoxib, 120 mg/day, or placebo for 7 days. Probing depth, clinical attachment level (CAL), gingival recession, visible plaque index, bleeding on probing, linear distance (LD) from the cemento-enamel junction to the alveolar crest, and analysis of the gray levels were recorded before and 1 month after the therapies. The prostaglandin E(2) (PGE(2)) level in the gingival crevicular fluid (GCF) was measured by radioimmunoassay at the beginning of the study and 7 and 30 days after treatment. RESULTS: No significant difference in the clinical parameters was observed between the groups at the end of the experimental period, although both groups presented significant improvement in all variables examined. There was a decrease in CAL from 5.54 +/- 0.47 mm to 3.59 +/- 0.53 mm in the test group and from 5.92 +/- 1.10 mm to 3.69 +/- 0.80 mm in the control group. A significant reduction in PGE(2) was found after 7 days of treatment. LD differed between the groups. CONCLUSION: Etoricoxib did not promote additional improvement in the clinical parameters; however, it produced an initial reduction in the PGE(2) levels in the GCF, which could be related to the discrete improvement in the bone condition.

Gastrointestinal dysmotility in 5-fluorouracil-induced intestinal mucositis outlasts inflammatory process resolution.

AIM: To evaluate gastrointestinal motility during 5-fluorouracil (5-FU)-induced intestinal mucositis. MATERIALS AND METHODS: Wistar rats received 5-FU (150 mg kg(-1), i.p.) or saline. After the 1st, 3rd, 5th, 15th and 30th day, sections of duodenum, jejunum and ileum were removed for assessment of epithelial damage, apoptotic and mitotic indexes, MPO activity and GSH concentration. In order to study gastrointestinal motility, on the 3rd or 15th day after 5-FU treatment, gastric emptying in vivo was measured by scintilographic method, and stomach or duodenal smooth muscle contractions induced by CCh were evaluated in vitro. RESULTS: On the third day of treatment, 5-FU induced a significant villi shortening, an increase in crypt depth and intestinal MPO activity and a decrease in villus/crypt ratio and GSH concentration. On the first day after 5-FU there was an increase in the apoptosis index and a decrease in the mitosis index in all intestinal segments. After the 15th day of 5-FU treatment, a complete reversion of all these parameters was observed. There was a delay in gastric emptying in vivo and a significant increase in gastric fundus and duodenum smooth muscle contraction, after both the 3rd and 15th day. CONCLUSION: 5-FU-induced gastrointestinal dysmotility outlasts intestinal mucositis.

Amifostine (Wr-2721) prevents indomethacin-induced gastric damage in rats: role of non-protein sulfhydryl groups and leukocyte adherence.

This study was designed to evaluate the protective effect of amifostine on indomethacin-induced gastric damage, and the role of increased gastric non-protein sulfhydryl groups (NP-SH) and decreased leukocyte adherence in this event. Wistar rats were pretreated with amifostine (10, 30, or 90 mg/kg intraperitoneal (i.p.) or subcutaneous (s.c.)) or saline. After 30 min, the rats received indomethacin (20 mg/kg, by gavage) and were then killed 3 hr later. Macroscopic and microscopic gastric damage, concentration of gastric NP-SH, prostaglandin E2 (PGE2), and mesenteric leukocyte adherence (intravital microscopy) were assessed. Amifostine prevented significantly (P < 0.05), macroscopic or microscopic, indomethacin-induced gastric damage, and increased gastric NP-SH, in a dose-dependent manner, with a maximal effect at a dose of 90 mg/kg. Subcutaneous, but not i.p., amifostine administration decreased (P < 0.05) the indomethacin-induced increase in leukocyte adherence. Indomethacin-induced PGE2 depletion was not reversed by amifostine. Amifostine has a protective effect against indomethacin-induced gastropathy by increasing gastric NP-SH and decreasing leukocyte adherence.

Effect of sodium alendronate on alveolar bone resorption in experimental periodontitis in rats.

BACKGROUND: Bisphosphonates are potent inhibitors of bone resorption and were shown to inhibit bone resorption in experimental periodontitis by unknown mechanisms. We studied the effect of the aminobisphosphonate sodium alendronate (SA) in experimental periodontitis. Wistar rats were subjected to ligature placement around the second upper left molars. METHODS: Animals were treated with SA 0.01 to 0.25 mg/kg subcutaneously (sc), either 1 hour before (prophylactic) or starting 5 days after (therapeutic) periodontitis induction and daily until the rats were sacrificed (11 days). Controls received saline. Animals were weighed daily. Alveolar bone loss was measured as the difference (in millimeters) between the cusp tip and the alveolar bone. The periodontium and the surrounding gingivae were examined at histopathology, and the neutrophil influx into the gingivae was assayed using myeloperoxidase activity. The local bacterial flora was assessed through culture of the gingival tissue in standard aerobic and anaerobic media. RESULTS: Alveolar bone loss was significantly and dose dependently inhibited by SA either as a prophylactic or therapeutic treatment compared to the control. SA reduced tissue lesion at histopathology, with partial preservation of the periodontium, coupled to decreased myeloperoxidase activity compared to the control. The reduced neutrophil influx was also shown in carrageenan-induced peritonitis, used as a control experiment for this parameter. SA also significantly inhibited the growth of pigmented bacilli and Fusobacterium nucleatum, which are important in the pathogenesis of periodontal disease. SA also inhibited the in vitro growth of isolated Peptostreptococcus sp. CONCLUSION: Sodium alendronate preserves alveolar bone resorption and has anti-inflammatory and antibacterial activities in experimental periodontitis.