Protective effects of chronic treatment with a standardized extract of Ginkgo biloba L. in the prefrontal cortex and dorsal hippocampus of middle-aged rats.

This study assessed the effects of chronic treatment with a standardized extract of Ginkgo biloba L. (EGb) on short-term and long-term memory as well as on anxiety-like and locomotor activity using the plus-maze discriminative avoidance task (PM-DAT). Additionally, we evaluated the antioxidant and neuroprotective effects of EGb on the prefrontal cortex (PFC) and dorsal hippocampus (DH) of middle-aged rats using the comet assay. Twelve-month-old male Wistar rats were administered vehicle or EGb (0.5mgkg(-1) or 1.0gkg(-1)) for 30days. Behavioural data showed that EGb treatment improved short-term memory. Neither an anti-anxiety effect nor a change in locomotor activity was observed. Twenty-four hours after the behavioural tests, the rats were decapitated, and the PFC and DH were quickly dissected out and prepared for the comet assay. The levels of DNA damage in the PFC were significantly lower in rats that were treated with 1.0gkg(-1) EGb. Both doses of EGb decreased H2O2-induced DNA breakage in cortical cells, whereas the levels of DNA damage in the EGb-treated animals were significantly lower than those in the control animals. No significant differences in the level of DNA damage in hippocampal cells were observed among the experimental groups. EGb treatment was not able to reduce H2O2-induced DNA damage in hippocampal cells. Altogether, our data provide the first demonstration that chronic EGb treatment improved the short-term memory of middle-aged rats, an effect that could be associated with a reduction in free radical production in the PFC. These data suggest that EGb treatment might increase the survival of cortical neurons and corroborate and extend the view that EGb has protective and therapeutic properties.

Paradoxical role of SOX2 in gastric cancer.

Sox2 is a critical regulator of embryogenesis and necessary for cellular reprogramming. It also plays an important role in tissue homeostasis and regeneration, maintaining the population of undifferentiated adult stem cells. Like various developmental and stem cell genes, SOX2 is aberrantly expressed and amplified in several human cancers. Moreover, functional studies have shown that it regulates many biological processes including cell proliferation, apoptosis, self-renewal and invasion. While it is oncogenic in most cancers, SOX2 activity is controversial in gastric cancer, where it might behave as a tumor suppressor in some situations. In this review, we discuss its role in cancer biology, with particular attention to what is known about the involvement of SOX2 in gastric cancer biology.

Role of pentoxifylline in non-alcoholic fatty liver disease in high-fat diet-induced obesity in mice.

AIM: To study pentoxifylline effects in liver and adipose tissue inflammation in obese mice induced by high-fat diet (HFD). METHODS: Male swiss mice (6-wk old) were fed a high-fat diet (HFD; 60% kcal from fat) or AIN-93 (control diet; 15% kcal from fat) for 12 wk and received pentoxifylline intraperitoneally (100 mg/kg per day) for the last 14 d. Glucose homeostasis was evaluated by measurements of basal glucose blood levels and insulin tolerance test two days before the end of the protocol. Final body weight was assessed. Epididymal adipose tissue was collected and weighted for adiposity evaluation. Liver and adipose tissue biopsies were homogenized in solubilization buffer and cytokines were measured in supernatant by enzyme immunoassay or multiplex kit, respectively. Hepatic histopathologic analyses were performed in sections of paraformaldehyde-fixed, paraffin-embedded liver specimens stained with hematoxylin-eosin by an independent pathologist. Steatosis (macrovesicular and microvesicular), ballooning degeneration and inflammation were histopathologically determined. Triglycerides measurements were performed after lipid extraction in liver tissue. RESULTS: Pentoxifylline treatment reduced microsteatosis and tumor necrosis factor (TNF)-α in liver (156.3 ± 17.2 and 62.6 ± 7.6 pg/mL of TNF-α for non-treated and treated obese mice, respectively; P < 0.05). Serum aspartate aminotransferase levels were also reduced (23.2 ± 6.9 and 12.1 ± 1.6 U/L for non-treated and treated obese mice, respectively; P < 0.05) but had no effect on glucose homeostasis. In obese adipose tissue, pentoxifylline reduced TNF-α (106.1 ± 17.6 and 51.1 ± 9.6 pg/mL for non-treated and treated obese mice, respectively; P < 0.05) and interleukin-6 (340.8 ± 51.3 and 166.6 ± 22.5 pg/mL for non-treated and treated obese mice, respectively; P < 0.05) levels; however, leptin (8.1 ± 0.7 and 23.1 ± 2.9 ng/mL for non-treated and treated lean mice, respectively; P < 0.05) and plasminogen activator inhibitor-1 (600.2 ± 32.3 and 1508.6 ± 210.4 pg/mL for non-treated and treated lean mice, respectively; P < 0.05) levels increased in lean adipose tissue. TNF-α level in the liver of lean mice also increased (29.6 ± 6.6 and 75.4 ± 12.6 pg/mL for non-treated and treated lean mice, respectively; P < 0.05) while triglycerides presented a tendency to reduction. CONCLUSION: Pentoxifylline was beneficial in obese mice improving liver and adipose tissue inflammation. Unexpectedly, pentoxifylline increased pro-inflammatory markers in the liver and adipose tissue of lean mice.

Thalidomide controls adipose tissue inflammation associated with high-fat diet-induced obesity in mice.

INTRODUCTION: Immunosuppressant agents modulate the activity of the immune system and control adipose tissue inflammatory responses associated with obesity. Controlling adipose tissue inflammation represents an interesting option for inhibiting the low-grade inflammatory state in obese subjects and for preventing obesity-associated pathologies. In this work, we assessed the effects of thalidomide on the inflammatory response in adipose tissue as well as on systemic inflammatory marker expression in the well-established high-fat diet-induced obesity mouse model. METHODS: Swiss male mice were fed a high-fat diet (60% kcal from fat) for 12 weeks and received thalidomide for the last 10 days (100 mg.kg-1). Adipokine levels were measured in serum and adipose tissue by EIA and real-time quantitative PCR, respectively. Adipose tissue infiltrating macrophages were identified by immunohistochemistry and western blot analysis of F4/80 marker expression. Other inflammatory markers, such as c-Jun N-terminal kinase (JNK) phosphorylation and monocyte chemoattractant protein-1 (MCP-1) production, were also evaluated by western blot analysis. In vitro assays using 3T3-L1 adipocytes were also conducted to evaluated adipokine release. RESULTS: In obese mice, thalidomide administration induced a reduction in adiposity accompanied by a reduction of tumor necrosis factor-α (TNF-α), leptin and MCP-1 adipose tissue production, macrophage infiltration and JNK activation. TNF-α and leptin serum levels were also reduced by thalidomide treatment in obese mice. In vitro, the release of basal TNF-α and lipopolysaccharide (LPS)-induced MCP-1 was inhibited in 3T3-L1 cells. SIGNIFICANCE: Our results suggest that drugs that can modulate the inflammatory status as well as control adipose tissue expansion could represent an interesting approach in the management of obesity, highlighting the need for further development of such compounds.

Hepcidin expression in colon during trinitrobenzene sulfonic acid-induced colitis in rats.

AIM: To investigate hepcidin expression, interleukin-6 (IL-6) production and iron levels in the rat colon in the presence of trinitrobenzene sulfonic acid (TNBS)-induced colitis. METHODS: In rats, we evaluated the severity of colitis induced by repeated TNBS administration using macroscopic and microscopic scoring systems and myeloperoxidase activity measurements. The colonic levels of hepcidin, tumor necrosis factor alpha (TNF-α), IL-10 and IL-6 were measured by Enzyme-Linked Immunosorbent Assay, and hepcidin-25 expression and iron deposition were analyzed by immunohistochemistry and the Prussian blue reaction, respectively. Stat-3 phosphorylation was assessed by Western blot analysis. Hematological parameters, iron and transferrin levels, and transferrin saturation were also measured. Additionally, the ability of iron, pathogen-derived molecules and IL-6 to induce hepcidin expression in HT-29 cells was evaluated. RESULTS: Repeated TNBS administration to rats resulted in macroscopically and microscopically detectable colon lesions and elevated colonic myeloperoxidase activity. Hepcidin-25 protein levels were increased in colonic surface epithelia in colitic rats (10.2 ± 4.0 pg/mg protein vs 71.0 ± 8.4 pg/mg protein, P < 0.01). Elevated IL-6 levels (8.2 ± 1.7 pg/mg protein vs 14.7 ± 0.7 pg/mg protein, P < 0.05), TNF-α levels (1.8 ± 1.2 pg/mg protein vs 7.4 ± 2.1 pg/mg protein, P < 0.05) and Stat-3 phosphorylation were also observed. Systemic alterations in iron homeostasis, hepcidin levels and anemia were not detected in colitic rats. Iron deposition in the colon was only observed during colitis. Hepcidin gene expression was increased in HT-29 cells after IL-6 and lipopolysaccharide [a toll-like receptor 4 (TLR-4) ligand] treatment. Deferoxamine, ferric citrate and peptidoglycan (a TLR-2 ligand) were unable to alter the in vitro expression of hepcidin in HT-29 cells. CONCLUSION: Colitis increased local hepcidin-25 expression, which was associated with the IL-6/Stat-3 signaling pathway. An increase in local iron sequestration was also observed, but additional studies are needed to determine whether this sequestration is a defensive or pathological response to intestinal inflammation.

Nitric oxide interferes with hypoxia signaling during colonic inflammation.

CONTEXT: Intestinal inflammation can induce a local reduction in oxygen levels that triggers an adaptive response centered on the expression of hypoxia-inducible factors (HIFs). Nitric oxide, a well-described inflammatory mediator, may interfere with hypoxia signaling. OBJECTIVES: We aimed to evaluate the role of nitric oxide in hypoxia signaling during colonic inflammation. METHODS: Colitis was induced by single (acute) or repeated (reactivated colitis) trinitrobenzenosulfonic acid administration in rats. In addition, one group of rats with reactivated colitis was also treated with Nw-Nitro-L-arginine methyl ester hydrochloride to block nitric oxide synthase. Colitis was assessed by macroscopic score and myeloperoxidase activity in the colon samples. Hypoxia was determined using the oxygen-dependent probe, pimonidazole. The expression of HIF-1α and HIF-induced factors (vascular endothelial growth factor - VEGF and apelin) was assessed using Western blotting. RESULTS: The single or repeated administration of trinitrobenzenosulfonic acid to rats induced colitis which was characterized by a high macroscopic score and myeloperoxidase activity. Hypoxia was observed with both protocols. During acute colitis, HIF-1α expression was not increased, but VEGF and apelin were increased. HIF-1α expression was inhibited during reactivated colitis, and VEGF and apelin were not increased. Nw-Nitro-L-arginine methyl ester hydrochloride blockade during reactivated colitis restored HIF-1α, VEGF and apelin expression. CONCLUSIONS: Nitric oxide could interfere with hypoxia signaling during reactivated colitis inflammation modifying the expression of proteins regulated by HIF-1α.

Methylation pattern of THBS1, GATA-4, and HIC1 in pediatric and adult patients infected with Helicobacter pylori.

BACKGROUND: Helicobacter pylori infection is usually acquired in childhood and persists into adulthood if untreated. The bacterium induces a chronic inflammatory response, which is associated with epigenetic alterations in oncogenes, tumor-suppressor genes, cell-cycle regulators, and cell-adhesion molecules. AIM: The aim of this study was to analyze the effect of H. pylori infection on the methylation status of Thrombospondin-1 (THBS1), Hypermethylated in cancer 1 (HIC1) and Gata binding protein-4 (GATA-4) in gastric biopsy samples from children and adults infected or uninfected with the bacterium and in samples obtained from gastric cancer patients. METHODS: The methylation pattern was analyzed with methylation-specific PCR. RESULTS: Our results showed that H. pylori infection was associated with methylation of the promoter regions of the THBS1 and GATA-4 genes in pediatric and adult samples (p < 0.01). HIC1 showed the lowest level of methylation, which was not an early event during gastric carcinogenesis. CONCLUSIONS: The results from this study indicate that methylation of THBS1 and GATA-4 occurs in the early stages of chronic gastritis and gastric cancer in association with H. pylori infection; however, in gastric cancer samples, other mechanisms cooperate with the down-regulation of these genes. Methylation of HIC1 may not be the principal mechanism implicated in its down-regulation in gastric cancer samples.

MGMT and MLH1 methylation in Helicobacter pylori-infected children and adults.

AIM: To evaluate the association between Helicobacter pylori (H. pylori) infection and MLH1 and MGMT methylation and its relationship with microsatellite instability (MSI). METHODS: The methylation status of the MLH1 and MGMT promoter region was analysed by methylation specific methylation-polymerase chain reaction (MSP-PCR) in gastric biopsy samples from uninfected or H. pylori-infected children (n = 50), from adults with chronic gastritis (n = 97) and from adults with gastric cancer (n = 92). MLH1 and MGMT mRNA expression were measured by real-time PCR and normalised to a constitutive gene (ß actin). MSI analysis was performed by screening MSI markers at 4 loci (Bat-25, Bat-26, D17S250 and D2S123) with PCR; PCR products were analysed by single strand conformation polymorphism followed by silver staining. Statistical analyses were performed with either the χ(2) test with Yates continuity correction or Fisher's exact test, and statistical significance for expression analysis was assessed using an unpaired Student's t-test. RESULTS: Methylation was not detected in the promoter regions of MLH1 and MGMT in gastric biopsy samples from children, regardless of H. pylori infection status. The MGMT promoter was methylated in 51% of chronic gastritis adult patients and was associated with H. pylori infection (P < 0.05); this region was methylated in 66% of gastric cancer patients, and the difference in the percentage of methylated samples between these patients and those from H. pylori-infected chronic gastritis patients was statistically significant (P < 0.05). MLH1 methylation frequencies among H. pylori-infected and non-infected chronic gastritis adult patients were 13% and 7%, respectively. We observed methylation of the MLH1 promoter (39%) and increased MSI levels (68%) in samples from gastric cancer patients in comparison to samples from H. pylori-infected adult chronic gastritis patients (P < 0.001 and P < 0.01, respectively). The frequency of promoter methylation for both genes was higher in gastric cancer samples than in H. pylori-positive chronic gastritis samples (P < 0.05). The levels of MLH1 and MGMT mRNA were significantly reduced in chronic gastritis samples that were also hypermethylated (P < 0.01). CONCLUSION: In summary, MGMT and MLH1 methylation did not occur in earlier-stage H. pylori infections and thus might depend on the duration of infection.

Infliximab modifies mesenteric adipose tissue alterations and intestinal inflammation in rats with TNBS-induced colitis.

OBJECTIVE: Infliximab is a monoclonal anti-TNF-α antibody that is used therapeutically to treat Crohn's disease (CD). High levels of pro-inflammatory cytokines, especially TNF-α, have been observed in the gastrointestinal tract of CD patients and were associated with alterations in the mesenteric adipose tissue, which also contributed to the high levels of adipokine release. The authors used a rat model of colitis that produces mesenteric adipose tissue alterations that are associated with intestinal inflammation to study the effects that infliximab treatment has on adipokine production, morphological alterations in adipose tissue and intestinal inflammation. MATERIAL AND METHODS: The ability of infliximab to neutralize rat TNF-α was evaluated in vitro using U937 cells. Colitis was induced by repeated intracolonic trinitrobenzene sulfonic acid instillations and was evaluated by macroscopic score, histopathological analysis, myeloperoxidase activity, TNF-α and IL-10 expression as well as iNOS (inducible NO synthase) expression and JNK phosphorylation in colon samples. The alterations in adipose tissue were assessed by TNF-α, IL-10, leptin, adiponectin and resistin levels as well as adipocyte size and peroxisome proliferator-activated receptor (PPAR)-γ expression. RESULTS: Infliximab treatment controlled intestinal inflammation, which reduced lesions and neutrophil infiltration. Inflammatory markers, such as iNOS expression and JNK phosphorylation, were also reduced. In mesenteric adipose tissue, infliximab increased the production of IL-10 and resistin, which was associated with the restoration of adipocyte morphology and PPAR-γ expression. CONCLUSIONS: Our results suggest that infliximab could contribute to the control of intestinal inflammation by modifying adipokine production by mesenteric adipose tissue.

Effects of methotrexate on inflammatory alterations induced by obesity: an in vivo and in vitro study.

Immunosuppressant drugs, such as methotrexate, are able to inhibit cytokine production and leukocyte migration to inflammatory foci; therefore, they could modify the establishment of inflammation in adipose tissue during obesity. Thus, we studied the effects of methotrexate in vivo on high-fat diet induced-obesity in mice and in vitro in isolated and co-cultured adipocytes and macrophages. Obese mice treated with methotrexate presented reduced serum levels of TNF-α, insulin and glucose, and an improvement of insulin sensitivity. Adipose tissue from these mice produced less proinflammatory (TNF-α, IL-6, leptin) and more anti-inflammatory adipokines (adiponectin and IL-10) associated with reduced macrophage infiltration and inflammation. Cytokine inhibition was also confirmed in isolated and co-cultured adipocytes and macrophages. Methotrexate presented anti-lipolytic effect in vivo and, in vitro through adenosine release. Drugs that combine anti-lipolytic effect and the ability to control inflammation in adipose tissue could play a role in the control of insulin resistance and other pathologies associated with obesity.

Helicobacter pylori antibiotic resistance in Brazil: clarithromycin is still a good option.

CONTEXT: The antibiotic susceptibility is the cornerstone for the eradication therapies of Helicobacter pylori. OBJECTIVES: To evaluate the prevalence of primary resistance of H. pylori was evaluated in an urban Brazilian population. METHODS: H. pylori isolates were obtained from patients submitted to an upper gastrointestinal endoscopy for the evaluation of dyspeptic symptoms. Biopsies from antrum, corpus and fundus were taken to determine the antibiotic susceptibility of H. pylori isolates. The minimal inhibitory concentration of furazolidone and bismuth were routinely determined by agar dilution method and the minimal inhibitory for amoxicillin, clarithromycin, tetracycline, levofloxacin, and metronidazole were routinely determined with the E-test. RESULTS: Fifty-four patients were included. In vitro antimicrobial susceptibility of H. pylori strains were obtained from 39 patients. Resistance to metronidazole was detected in 20 patients (51%), to clarithromycin in 3 patients (8%), to levofloxacin in 9 patients (23%) and to bismuth in 2 patients (5%). There was no observed resistance to amoxicillin, tetracycline or furazolidone. CONCLUSION: Due to the low amoxicillin and clarithromycin resistance observed in this study, therapies using these antimicrobials remain appropriated first-line H. pylori therapy.

Anti-inflammatory effects of yerba maté extract (Ilex paraguariensis) ameliorate insulin resistance in mice with high fat diet-induced obesity.

The aim of the present study was to evaluate the effects of yerba maté extract upon markers of insulin resistance and inflammatory markers in mice with high fat diet-induced obesity. The mice were introduced to either standard or high fat diets. After 12 weeks on a high fat diet, mice were randomly assigned to one of the two treatment conditions, water or yerba maté extract at 1.0 gkg(-1). After treatment, glucose blood level and hepatic and soleus muscle insulin response were evaluated. Serum levels of TNF-α and IL-6 were evaluated by ELISA, liver tissue was examined to determine the mRNA levels of TNF-α, IL-6 and iNOS, and the nuclear translocation of NF-κB was determined by an electrophoretic mobility shift assay. Our data show improvements in both the basal glucose blood levels and in the response to insulin administration in the treated animals. The molecular analysis of insulin signalling revealed a restoration of hepatic and muscle insulin substrate receptor (IRS)-1 and AKT phosphorylation. Our data show that the high fat diet caused an up-regulation of the TNF-α, IL-6, and iNOS genes. Although after intervention with yerba maté extract the expression levels of those genes returned to baseline through the NF-κB pathway, these results could also be secondary to the weight loss observed. In conclusion, our results indicate that yerba maté has a potential anti-inflammatory effect. Additionally, these data demonstrate that yerba maté inhibits hepatic and muscle TNF-α and restores hepatic insulin signalling in mice with high fat diet-induced obesity.

Synthesis and pharmacological characterization of a novel nitric oxide-releasing diclofenac derivative containing a benzofuroxan moiety.

1-oxy-benzo[1,2,5]oxadiazol-5-ylmethyl [2-(2,6-dichloro-phenylamino)-phenyl]-acetate, a new diclofenac derivative bearing a benzofuroxan heterocyclic moiety in its structure, was prepared by the reaction of sodium diclofenac and 5-bromomethyl-benzo[1,2,5]oxadiazole 1-oxide. Pharmacological characterization of this modified diclofenac maintained the anti-inflammatory activity similar to its parent compound assayed in vitro and in vivo. The ulcerogenic properties of native diclofenac were not observed with this modified compound, despite the inhibition of prostaglandin E2 gastric content. The better gastric tolerability seems to be related to nitric oxide release ability.

Evaluation of pantoprazole formulations in different dissolution apparatus using biorelevant medium.

PURPOSE: The study was developed to compare the in vitro dissolution profiles of pantoprazole (CAS 102625-70-7) formulations in both The United States Pharmacopeia (USP) apparatus 2 and 3 by applying biorelevant medium. Moreover, an in vitro-in vivo relationship was proposed considering in vivo data from a previously published study. METHODS: In vitro dissolution profiles were evaluated in biorelevant medium in USP apparatus 2 and 3 and the dissolution curves were either compared by the similarity factor (f2) or a model-independent approach. The fraction of drug dissolved in vitro in apparatus 2 was compared with the fraction of drug absorbed in vivo, which was obtained from a retrospective in vivo study. An in vitro-in vivo relationship analysis was then applied to elucidate the overall absorption characteristics of formulations. RESULTS: The dissolution profiles of formulations demonstrated similar disposition in biorelevant medium in both USP apparatus 2 and 3. The dissolution profiles were described by f2 model in apparatus 2 and Weibull's function in apparatus 3. The vitro-in vivo relationship analysis showed that the formulations exhibited permeability rate-limiting absorption. CONCLUSION: Biorelevant medium in both USP apparatus 2 and 3 may be used as a tool to predict in vivo disposition of formulations of pantoprazole. Furthermore, it can be argued that biowaiver can be granted for enteric coated formulations of pantoprazole on the basis of in vitro dissolution profile.

The immunosuppressant drug, thalidomide, improves hepatic alterations induced by a high-fat diet in mice.

BACKGROUND: Pro-inflammatory cytokines, such as tumour necrosis factor (TNF)-alpha, are known to be involved in the establishment of insulin resistance. Insulin resistance plays a key role in the development of obesity-related pathologies, such as type 2 diabetes and non-alcoholic fatty liver disease (NAFLD). The state of chronic inflammation associated with obesity led us to hypothesize that TNF-alpha blockade may have an effect on experimentally obese animals. AIMS: We studied the effects of thalidomide, an immunosuppressant and anti-TNF-alpha drug, on hepatic alterations that were induced by a high-fat diet (HFD) in mice. METHODS: Obesity was induced in Swiss mice using a HFD for 12 weeks. Thalidomide-treated animals received thalidomide i.p. (100 mg/kg/day, 10 days). Glucose, aspartate aminotransferases and alanine aminotransferases levels were assessed in the blood. Insulin and glucose tolerance tests were performed. The liver was excised for histological, triglyceride, gene and protein expression analyses. RESULTS: We found improvements in both the basal glucose blood levels and the response to insulin administration in the treated animals. The molecular analysis of insulin signalling revealed a restoration of the hepatic insulin receptor substrate (IRS)-1 and AKT phosphorylation. The hepatic expression of TNF-alpha was inhibited and the levels correlated with a significant reduction in the steatosis area. Other hepatic inflammatory markers, such as iNOS and suppressor of cytokine signalling (SOCS-3), were also reduced. CONCLUSIONS: We suggest that immunosuppressant drugs that target TNF-alpha and that may also contribute to reductions in the inflammatory markers that are associated with obesity could be a therapeutic option in NAFLD and type 2 diabetes.

Pharmacokinetic and local toxicity studies of liposome-encapsulated and plain mepivacaine solutions in rats.

The pharmacokinetics and the local toxicity of commercial and liposome-encapsulated mepivacaine formulations injected intra-orally in rats were studied. Animals were divided in groups (n = 4-6) and treated with 0.1 mL of the formulations: 2% mepivacaine with 1:100,000 epinephrine (MVC(2%EPI)), 3% mepivacaine (MVC(3%)), and 2% liposome-encapsulated mepivacaine (MVC(LUV)). The results showed that the 2% liposome-encapsulated mepivacaine reduced C(max), prolonged AUC(0-infinity) and t(1/2) compared with 3% plain and 2% vasoconstritor-associated mepivacaine, after intraoral injection. In addition, it was also observed that liposomal mepivacaine might protect the tissue against local inflammation evoked by plain or vasoconstrictors-associated mepivacaine, giving supporting evidence for its safety and possible clinical use in dentistry.

Effects of Helicobacter pylori infection on the expressions of Bax and Bcl-2 in patients with chronic gastritis and gastric cancer.

The aim of the present study is to evaluate the influence of Helicobacter pylori on Bax and Bcl-2 mRNA and protein levels in patients with chronic gastritis and gastric cancer. The study included 217 patients, of which 26 were uninfected; 127 had chronic gastritis and were H. pylori-positive, and 64 had gastric cancer. Bacterial genotypes were evaluated by PCR, and the expression values were determined by quantitative real-time PCR and immunohistochemistry. Our data showed that the up-regulationary effects of H. pylori infection on the pro-apoptotic gene, Bax, were stronger than its induction of Bcl-2; this effect may increase apoptosis in patients with chronic gastritis. In patients with gastric cancer, the up-regulation of the anti-apoptotic gene, Bcl-2, counteracted the pro-apoptotic effects of Bax, leading to a deregulation of apoptosis-associated gene expression, favoring cell proliferation. Thus, the disturbance in Bax and Bcl-2 balance, induced by H. pylori, might be important in gastric cancer development.

Methotrexate is effective in reactivated colitis and reduces inflammatory alterations in mesenteric adipose tissue during intestinal inflammation.

Mesenteric white adipose tissue hypertrophy and modifications in adipocytokine production are described features of Crohn's disease. Experimentally, mesenteric white adipose tissue alterations, associated with intestinal inflammation, can be induced in a model of reactivated colitis by repeated administration of intrarectal trinitrobenzenosulfonic acid (TNBS) in ethanol solution. Crohn's disease patients refractory to corticosteroid treatment are frequently treated with methotrexate; however, there is no information regarding the drug's effect on adipose tissue alterations and in a reactivated colitis experimental model. Thus, we evaluated the effect of methotrexate upon mesenteric WAT alterations and inflammatory features in experimental colitis in rats. Colitis status was evaluated by macroscopic score, histopathological analysis, myeloperoxidase activity, TNF-alpha and IL-10 expression, as well as iNOS and TLR-4 expression in colon samples. The adipose tissue alterations were assessed by TNF-alpha, IL-10, leptin and adiponectin production, as well as by macrophage infiltration evaluation. Methotrexate exerts an anti-inflammatory activity in experimental reactivated colitis by regulating the shift from Th1 to Th2 cytokines, reducing TNF-alpha and improving IL-10 production. Additionally, methotrexate reduces other inflammatory parameters in the colon, such as iNOS and TLR-4 expression. In mesenteric white adipose tissue, methotrexate treatment reduces the production of pro- and anti-inflammatory adipocytokines as well as macrophage infiltration, suggesting that immunosuppressant drugs diminish adipose tissue inflammatory alterations associated with intestinal inflammation.

Antiobesity effects of yerba maté extract (Ilex paraguariensis) in high-fat diet-induced obese mice.

Because the potential of yerba maté (Ilex paraguariensis) has been suggested in the management of obesity, the aim of the present study was to evaluate the effects of yerba maté extract on weight loss, obesity-related biochemical parameters, and the regulation of adipose tissue gene expression in high-fat diet-induced obesity in mice. Thirty animals were randomly assigned to three groups. The mice were introduced to standard or high-fat diets. After 12 weeks on a high-fat diet, mice were randomly assigned according to the treatment (water or yerba maté extract 1.0 g/kg). After treatment intervention, plasma concentrations of total cholesterol, high-density lipoprotein cholesterol, triglyceride, low-density lipoprotein (LDL) cholesterol, and glucose were evaluated. Adipose tissue was examined to determine the mRNA levels of several genes such as tumor necrosis factor-alpha (TNF-alpha), leptin, interleukin-6 (IL-6), C-C motif chemokine ligand-2 (CCL2), CCL receptor-2 (CCR2), angiotensinogen, plasminogen activator inhibitor-1 (PAI-1), adiponectin, resistin, peroxisome proliferator-activated receptor-gamma(2) (PPAR-gamma(2)), uncoupling protein-1 (UCP1), and PPAR-gamma coactivator-1 alpha (PGC-1 alpha). The F4/80 levels were determined by immunoblotting. We found that obese mice treated with yerba maté exhibited marked attenuation of weight gain, adiposity, a decrease in epididymal fat-pad weight, and restoration of the serum levels of cholesterol, triglycerides, LDL cholesterol, and glucose. The gene and protein expression levels were directly regulated by the high-fat diet. After treatment with yerba maté extract, we observed a recovery of the expression levels. In conclusion, our data show that yerba maté extract has potent antiobesity activity in vivo. Additionally, we observed that the treatment had a modulatory effect on the expression of several genes related to obesity.

Depot-specific alterations to insulin signaling in mesenteric adipose tissue during intestinal inflammatory response.

Current knowledge suggests that adipose tissue is an active organ, participating in intestinal and mesenteric disease. Additionally, adipose tissue surrounds the lymph nodes and has special properties, acting as a paracrine regulator of adjacent lymphoid tissues. These adipose tissue depots can express and secrete numerous cytokines, known as adipocytokines, which then modify the action of insulin in adipose tissue itself. Using a well-accepted model of intestinal inflammation, we studied insulin signaling in mesenteric adipose tissue (MAT) and in perinodal mesenteric adipose tissue (PAT). Our results showed that the action of insulin is modified during the intestinal inflammatory response in these adipose tissue depots. MAT became resistant to insulin signaling, as evaluated by the IRS/AKT pathway, in the inflammation. This resistant status was associated with high JNK activity and the presence of infiltrating macrophages. Conversely, the adipose tissue that involves the mesenteric lymph nodes acquired greater sensitivity to insulin signaling via IRS/AKT, probably via up-regulation of IRS during experimental colitis. We demonstrated experimentally the existence of site-specific adaptive alterations in two mesenteric adipose tissue depots to the intestinal inflammatory response, probably resulting in alterations in free fatty acids and other secretory products supplied by the adjacent tissues that could act as inflammatory modulator substances.