Decrease of miR-125a-5p in Gastritis and Gastric Cancer and Its Possible Association with H. pylori

PURPOSE

The aim of this study was to evaluate the expression of miR-125a-5p in patients with dyspeptic symptoms and gastric cancer, correlating them with the development of this cancer and H. pylori.

METHODS

Patients were divided in groups according to histopathological analysis (control, gastritis, and cancer groups). Polymerase chain reaction was performed to detect H. pylori and real-time quantitative PCR to determine miR-125a-5p expression.

RESULTS

H. pylori was detected in 44% of the patients, with prevalence in the gastritis and cancer groups. A statistically significant decrease of miR-125a-5p expression was found in the control positive (p = 0.0183*), gastritis positive (p = 0.0380*), and cancer positive (p = 0.0288*) groups when compared with the control negative group.

CONCLUSION

We suggest that decreased expression of the miRNA-125a-5p associated with the presence of the H. pylori is an important mechanism in gastric diseases and could be a possible marker for early diagnosis of gastric cancer.

Increased expression of interleukin-6 gene in gastritis and gastric cancer

Helicobacter pylori (H. pylori) induces an intense inflammatory response, mediated by proinflammatory cytokines, including interleukin (IL)-6 and its membrane receptor (IL-6R), which activates important signaling pathways in the development of gastric disease and cancer. We investigated the gene and protein expression of IL-6 and IL-6R and the influence of polymorphisms rs1800795, rs1800796, and rs1800797 on its gene expression together with H. pylori infection. Furthermore, an in-silico analysis was performed to support our results. Gastric biopsies were obtained from patients with gastric symptoms and patients with gastric cancer (GC) and were divided into groups (Control, Gastritis, and Cancer). H. pylori was detected by PCR. Real-time-qPCR was employed to determine gene expression, and western blot assay was used to analyze protein expression levels. PCR-RFLP was used to characterize IL-6 polymorphisms. Bioinformatics analyses were performed using the Gene Expression Omnibus (GEO) database and GEO2R to screen out differentially expressed genes (DEGs). H. pylori was detected in 43.3% of the samples. Statistically significant differences were found for IL-6 (P=0.0001) and IL-6R (P=0.0005) genes among the three groups, regardless of the presence of H. pylori. Among patients with H. pylori infection, the IL-6 and IL-6R gene and protein expressions were significantly increased, highlighting IL-6 gene overexpression in patients with GC. No statistically significant differences were found for the rs1800795, rs1800796, and rs1800797 polymorphisms compared to IL-6 gene expression. The results indicated that the IL-6 polymorphisms do not influence its expression, but IL-6 and IL-6R expression seems to be altered by the presence of H. pylori.

Dysregulated Expression of Apoptosis-Associated Genes and MicroRNAs and Their Involvement in Gastric Carcinogenesis

PURPOSE

Analyze the expression of caspase-9, Smac/DIABLO, XIAP, let-7a, and let-7b in patients with normal gastric tissue, chronic gastritis, and gastric adenocarcinoma.

METHODS

The expression of caspase-9, Smac/DIABLO, XIAP, let-7a, and let-7b by qRT-PCR was analyzed in 158 samples from 53 patients with normal gastric mucosa, 86 with chronic gastritis, and 19 with gastric cancer.

RESULTS

The comparison between the gastric cancer and the control group revealed a decreased expression of caspase-9 in gastric cancer tissues; considering the Helicobacter pylor presence, comparable results were revealed. Smac/DIABLO was increased in gastric cancer cells, while XIAP demonstrated no significant difference in the gene expression. The microRNA analysis revealed a decreased expression of let-7a and let-7b in samples positive to H. pylori infection and in gastric cancer group, regardless of the presence of the bacterium.

CONCLUSION

Our study provided some evidence of low activity of the intrinsic apoptosis pathway, as well as the influence of H. pylori on let-7a and let-7b expression.

First record of larvae of Hysterothylacium (Nematoda: Anisakidae) with zoonotic potential in the pirarucu Arapaima gigas (Osteichthyes: Arapaimidae) from South America

Third-stage larvae (L3) of Hysterothylacium sp. were collected by the first time in juveniles of pirarucu Arapaima gigas farmed in the Rio Preto da Eva, Amazonas state. Ninety-eight (98) out of 100 examined fish showed to be parasitized. Five hundred and ninety larvae of Hysterothylacium sp. were collected from the intestines, stomach and pyloric caeca. The mean intensity of parasite indexes was 6.02 (±5.75) ranging from 1 to 40 larvae per host and the mean abundance was 5.9 (±5.76). The A. gigas is the new host record for larvae of Hysterothylacium sp. in Brazil, and this is the first record of larvae of Hysterothylacium (Nematoda: Anisakidae) with zoonotic potential in the pirarucu from South America.

[Effect of intravenous administration of SO4Mg in the acute phase of myocardial infarct]

Fifty four patients (p) with acute myocardial infarction (40M; 14F) were entered into a prospective study where they received either intravenous magnesium sulphate (group A-27 p) or placebo (group B-27 p). The incidence of arrhythmias necessitating treatment was greater in group B (37%) than in group A (15%). Mortality was 18.5% in group B and 3.7% in group A. These results suggest that magnesium sulphate administration reduces the incidence of arrhythmias and death after acute myocardial infarction.

[Therapeutic effectiveness of intravenous magnesium sulfate in tachyarrhythmia. Apropos of 4 clinical cases]

This is a report about four patients with tachyarrhythmias successfully treated with intravenous magnesium sulfate. In two cases (supraventricular tachycardia and torsade de pointes) because they were resistant to other antiarrhythmic drugs, and in the remaining two cases (paroxistic atrial fibrillation) because they presented characteristic features of magnesium depletion. The efficacy, the rapid onset of action and the absence of adverse reactions must be emphasized and the authors suggest that larger and randomized trials should be carried out, in order to establish the real place of magnesium sulfate in the antiarrhythmic armamentarium.

Bronchodilator and antiulcer phenoxypyrimidinones

Series of 5-phenoxy-2(1H)-pyrimidinones, 5-phenoxy-4(3H)-pyrimidinones, and related compounds were prepared in a follow-up of a lead prepared as a potential cyclic nucleotide regulating agent. Compounds were evaluated for bronchodilator activity in histamine-challenged guinea pigs and for anticulcer activity in a cold-restraint, stressed rat ulcer model. Bronchodilator activity comparable to, or greater than, that of theophylline was found in both the 2(1H)- and 4(3H)-pyrimidinone series and was most prominent in analogues containing either an electron-withdrawing or -donating substituent in the para position of the phenoxy ring. Significant antiulcer activity was observed only in the 2(1H)-pyrimidinone series among three closely related analogues. One of these, 5-(m-methylphenoxy)-2(1H)-pyrimidinone (3), exhibited more potent antiulcer effects than the clinically useful antiulcer agent carbenoxolone, without demonstrating bronchodilator activity.

Metabolic effects of the biguanides and possible mechanism of action

The relationship between the biguanide inhibition of oxidations and their effect on glucose metabolism in vitro has been investigated. We found a good correlation between the concentration of biguanide causing a halfmaximal inhibition of pyruvate oxidation (Ki) and the concentration eliciting a half-maximal stimulation (Ks) of glucose uptake in several tissues from rat, guinea pig and pigeon. Guinea pig epididymal fat pad was the most sensitive tissue tested. Gluconeogenesis by minced guinea pig liver was inhibited by the biguanides. The ability of the biguanides to inhibit gluconeogenesis correlated well with their ability to inhibit pyruvate oxidation. Inhibition of oxidations by the biguanides does not appear to be a result of a direct inhibition of the enzymes catalyzing these oxidations but seems to be secondary to a primary effect on the coupled processes of electron transport and oxidative phosphorylation. We have summarized and discussed objections to the theory that the metabolic actions of the biguanides are a result of their inhibition of oxidative processes. Our conclusion is that the inhibition of oxidations caused by the biguanides is directly related to their metabolic and hypoglycemic effects.

The plasma free fatty acid rebound induced by nicotinic acid

The time course of the nicotinic acid-induced changes in levels of plasma free fatty acids (FFA) was examined. The plasma FFA response of fasted dogs to graded doses of nicotinic acid was shown to be biphasic: an initial depression of the level of plasma FFA was followed by a rebound elevation to supernormal levels. FFA rebound was not seen after the administration of the nicotinic acid homologue, pyridylacetic acid, or a variety of nicotinic acid metabolities. A similar pattern of FFA response was observed in fasted, normal rats. Adrenalectomy did not abolish the secondary elevation of FFA but did cause a somewhat delayed response. Hypophysectomy modified the time course of the response-the initial FFA decrease was prolonged-and the intensity of the FFA rebound was diminished. No rebound was observed in hypophysectomized, adrenalectomized rats. In normal rats, nicotinic acid caused a significant rise in the level of plasma corticosterone. A normal rebound pattern was observed in thyroidectomized rats. Reserpine, administered on a schedule designed to deplete catecholamine stores, altered the time course of plasma FFA changes only slightly. The results indicate that both the pituitary and adrenal functions are required for the expression of the rebound phenomenon after nicotinic acid administration.