In vitro inhibitory effects of imatinib mesylate on stromal cells and hematopoietic progenitors from bone marrow

Imatinib mesylate (IM) is used to treat chronic myeloid leukemia (CML) because it selectively inhibits tyrosine kinase, which is a hallmark of CML oncogenesis. Recent studies have shown that IM inhibits the growth of several non-malignant hematopoietic and fibroblast cells from bone marrow (BM). The aim of the present study was to evaluate the effects of IM on stromal and hematopoietic progenitor cells, specifically in the colony-forming units of granulocyte/macrophage (CFU-GM), using BM cultures from 108 1.5- to 2-month-old healthy Swiss mice. The results showed that low concentrations of IM (1.25 µM) reduced the growth of CFU-GM in clonogenic assays. In culture assays with stromal cells, fibroblast proliferation and α-SMA expression by immunocytochemistry analysis were also reduced in a concentration-dependent manner, with a survival rate of approximately 50% with a dose of 2.5 µM. Cell viability and morphology were analyzed using MTT and staining with acrydine orange/ethidium bromide. Most cells were found to be viable after treatment with 5 µM IM, although there was gradual growth inhibition of fibroblastic cells while the number of round cells (macrophage-like cells) increased. At higher concentrations (15 µM), the majority of cells were apoptotic and cell growth ceased completely. Oil red staining revealed the presence of adipocytes only in untreated cells (control). Cell cycle analysis of stromal cells by flow cytometry showed a blockade at the G0/G1 phases in groups treated with 5-15 µM. These results suggest that IM differentially inhibits the survival of different types of BM cells since toxic effects were achieved.

Gastric emptying of water in children with severe functional fecal retention

The objective of this study was to evaluate gastric emptying (GE) in pediatric patients with functional constipation. GE delay has been reported in adults with functional constipation. Gastric emptying studies were performed in 22 children with chronic constipation, fecal retention and fecal incontinence, while presenting fecal retention and after resuming regular bowel movements. Patients (18 boys, median age: 10 years; range: 7.2 to 12.7 years) were evaluated in a tertiary pediatric gastroenterology clinic. Gastric half-emptying time of water (reference range: 12 ± 3 min) was measured using a radionuclide technique immediately after first patient evaluation, when they presented fecal impaction (GE1), and when they achieved regular bowel movements (GE2), 12 ± 5 weeks after GE1. At study admission, 21 patients had reported dyspeptic symptoms, which were completely relieved after resuming regular bowel movements. Medians (and interquartile ranges) for GE1 and GE2 were not significantly different [27.0 (16) and 27.5 (21) min, respectively (P = 0.10)]. Delayed GE seems to be a common feature among children with chronic constipation and fecal retention. Resuming satisfactory bowel function and improvement in dyspeptic symptoms did not result in normalization of GE data.

AKT inhibitor suppresses hyperthermia-induced Ndrg2 phosphorylation in gastric cancer cells

Hyperthermia is one of the most effective adjuvant treatments for various cancers with few side effects. However, the underlying molecular mechanisms still are not known. N-myc downstream-regulated gene 2 (NDRG2), a tumor suppressor, has been shown to be involved in diverse cellular stresses including hypoxia, lipotoxicity, etc. In addition, Ndrg2 has been reported to be related to progression of gastric cancer. In the current study, our data showed that the apoptosis rate of MKN28 cells increased relatively rapidly to 13.4% by 24 h after treatment with hyperthermia (42°C for 1 h) compared to 5.1% in control cells (P < 0.05). Nevertheless, there was no obvious change in the expression level of total Ndrg2 during this process. Further investigation demonstrated that the relative phosphorylation levels of Ndrg2 at Ser332, Thr348 increased up to 3.2- and 1.9-fold (hyperthermia groupvs control group) at 3 h in MKN28 cells, respectively (P < 0.05). We also found that heat treatment significantly increased AKT phosphorylation. AKT inhibitor VIII (10 µM) decreased the phosphorylation level of Ndrg2 induced by hyperthermia. Accordingly, the apoptosis rate rose significantly in MKN28 cells (16.4%) treated with a combination of AKT inhibitor VIII and hyperthermia compared to that (6.8%) of cells treated with hyperthermia alone (P < 0.05). Taken together, these data demonstrated that Ndrg2 phosphorylation could be induced by hyperthermia in an AKT-dependent manner in gastric cancer cells. Furthermore, AKT inhibitor VIII suppressed Ndrg2 phosphorylation and rendered gastric cancer cells susceptible to apoptosis induced by hyperthermia.

Relationship of macrophage migration inhibitory factor levels in PBMCs, lesional skin and serum with disease severity and activity in vitiligo vulgaris

Melanocyte loss in vitiligo vulgaris is believed to be an autoimmune process. Macrophage migration inhibitory factor (MIF) is involved in many autoimmune skin diseases. We determined the possible role of MIF in the pathogenesis of vitiligo vulgaris, and describe the relationship between MIF expressions and disease severity and activity. Serum MIF concentrations and mRNA levels in PBMCs were measured in 44 vitiligo vulgaris patients and 32 normal controls, using ELISA and real-time RT-PCR. Skin biopsies from 15 patients and 6 controls were analyzed by real-time RT-PCR. Values are reported as median (25th-75th percentile). Serum MIF concentrations were significantly increased in patients [35.81 (10.98-43.66) ng/mL] compared to controls [7.69 (6.01-9.03) ng/mL]. MIF mRNA levels were significantly higher in PBMCs from patients [7.17 (3.59-8.87)] than controls [1.67 (1.23-2.42)]. There was also a significant difference in MIF mRNA levels in PBMCs between progressive and stable patients [7.86 (5.85-9.13)vs 4.33 (2.23-8.39)] and in serum MIF concentrations [40.47 (27.71-46.79) vs 26.80 (10.55-36.07) ng/mL]. In addition, the vitiligo area severity index scores of patients correlated positively with changes of both serum MIF concentrations (r = 0.488) and MIF mRNA levels in PBMCs (r = 0.426). MIF mRNA levels were significantly higher in lesional than in normal skin [2.43 (2.13-7.59)vs 1.18 (0.94-1.83)] and in patients in the progressive stage than in the stable stage [7.52 (2.43-8.84)vs 2.13 (1.98-2.64)]. These correlations suggest that MIF participates in the pathogenesis of vitiligo vulgaris and may be useful as an index of disease severity and activity.

Ziyuglycoside II-induced apoptosis in human gastric carcinoma BGC-823 cells by regulating Bax/Bcl-2 expression and activating caspase-3 pathway

Ziyuglycoside II is an active compound of Sanguisorba officinalis L. that has anti-inflammation, antioxidation, antibiosis, and homeostasis properties. We report here on the anticancer effect of ziyuglycoside II on human gastric carcinoma BGC-823 cells. We investigated the effects of ziyuglycoside II on cell growth, cell cycle, and cell apoptosis of this cell line. Our results revealed that ziyuglycoside II could inhibit the proliferation of BGC-823 cells by inducing apoptosis but not cell cycle arrest, which was associated with regulation of Bax/Bcl-2 expression, and activation of the caspase-3 pathway. Our study is the first to report the antitumor potential of ziyuglycoside II in BGC-823 gastric cancer cells. Ziyuglycoside II may become a potential therapeutic agent against gastric cancer in the future.

The hydrogen sulfide donor, Lawesson's reagent, prevents alendronate-induced gastric damage in rats

Our objective was to investigate the protective effect of Lawesson's reagent, an H2S donor, against alendronate (ALD)-induced gastric damage in rats. Rats were pretreated with saline or Lawesson's reagent (3, 9, or 27 µmol/kg, po) once daily for 4 days. After 30 min, gastric damage was induced by ALD (30 mg/kg) administration by gavage. On the last day of treatment, the animals were killed 4 h after ALD administration. Gastric lesions were measured using a computer planimetry program, and gastric corpus pieces were assayed for malondialdehyde (MDA), glutathione (GSH), proinflammatory cytokines [tumor necrosis factor (TNF)-α and interleukin (IL)-1β], and myeloperoxidase (MPO). Other groups were pretreated with glibenclamide (5 mg/kg, ip) or with glibenclamide (5 mg/kg, ip)+diazoxide (3 mg/kg,ip). After 1 h, 27 µmol/kg Lawesson's reagent was administered. After 30 min, 30 mg/kg ALD was administered. ALD caused gastric damage (63.35±9.8 mm2); increased levels of TNF-α, IL-1β, and MDA (2311±302.3 pg/mL, 901.9±106.2 pg/mL, 121.1±4.3 nmol/g, respectively); increased MPO activity (26.1±3.8 U/mg); and reduced GSH levels (180.3±21.9 µg/g). ALD also increased cystathionine-γ-lyase immunoreactivity in the gastric mucosa. Pretreatment with Lawesson's reagent (27 µmol/kg) attenuated ALD-mediated gastric damage (15.77±5.3 mm2); reduced TNF-α, IL-1β, and MDA formation (1502±150.2 pg/mL, 632.3±43.4 pg/mL, 78.4±7.6 nmol/g, respectively); lowered MPO activity (11.7±2.8 U/mg); and increased the level of GSH in the gastric tissue (397.9±40.2 µg/g). Glibenclamide alone reversed the gastric protective effect of Lawesson's reagent. However, glibenclamide plus diazoxide did not alter the effects of Lawesson's reagent. Our results suggest that Lawesson's reagent plays a protective role against ALD-induced gastric damage through mechanisms that depend at least in part on activation of ATP-sensitive potassium (KATP) channels.

Evidence for the involvement of peripheral β-adrenoceptors in delayed liquid gastric emptying induced by dipyrone, 4-aminoantipyrine, and antipyrine in rats

Dipyrone (Dp), 4-aminoantipyrine (AA), and antipyrine (At) delay liquid gastric emptying (GE) in rats. We evaluated adrenergic participation in this phenomenon in a study in male Wistar rats (250-300 g) pretreated subcutaneously with guanethidine (GUA), 100 mg·kg−1·day−1, or vehicle (V) for 2 days before experimental treatments. Other groups of animals were pretreated intravenously (iv) 15 min before treatment with V, prazosin (PRA; 1 mg/kg), yohimbine (YOH; 3 mg/kg), or propranolol (PRO; 4 mg/kg), or with intracerebroventricular (icv) administration of 25 µg PRO or V. The groups were treated iv with saline or with 240 µmol/kg Dp, AA, or At. GE was determined 10 min later by measuring the percentage of gastric retention (%GR) of saline labeled with phenol red 10 min after gavage. %GR (mean±SE, n=8) indicated that GUA abolished the effect of Dp (GUA vs V=31.7±1.6 vs47.1±2.3%) and of At (33.2±2.3 vs 54.7±3.6%) on GE and significantly reduced the effect of AA (48.1±3.2 vs67.2±3.1%). PRA and YOH did not modify the effect of the drugs. %GR (mean±SE, n=8) indicated that iv, but noticv, PRO abolished the effect of Dp (PROvs V=29.1±1.7 vs 46.9±2.7%) and At (30.5±1.7 vs 49±3.2%) and significantly reduced the effect of AA (48.4±2.6 vs 59.5±3.1%). These data suggest activation of peripheral β-adrenoceptors in the delayed GE induced by phenylpyrazolone derivatives.

Involvement of Src tyrosine kinase and protein kinase C in the expression of macrophage migration inhibitory factor induced by H2O2 in HL-1 mouse cardiac muscle cells

Macrophage migration inhibitory factor (MIF), a pleiotropic cytokine, plays an important role in the pathogenesis of atrial fibrillation; however, the upstream regulation of MIF in atrial myocytes remains unclear. In the present study, we investigated whether and how MIF is regulated in response to the renin-angiotensin system and oxidative stress in atrium myocytes (HL-1 cells). MIF protein and mRNA levels in HL-1 cells were assayed using immunofluorescence, real-time PCR, and Western blot. The result indicated that MIF was expressed in the cytoplasm of HL-1 cells. Hydrogen peroxide (H2O2), but not angiotensin II, stimulated MIF expression in HL-1 cells. H2O2-induced MIF protein and gene levels increased in a dose-dependent manner and were completely abolished in the presence of catalase. H2O2-induced MIF production was completely inhibited by tyrosine kinase inhibitors genistein and PP1, as well as by protein kinase C (PKC) inhibitor GF109203X, suggesting that redox-sensitive MIF production is mediated through tyrosine kinase and PKC-dependent mechanisms in HL-1 cells. These results suggest that MIF is upregulated by HL-1 cells in response to redox stress, probably by the activation of Src and PKC.

Transduction motif analysis of gastric cancer based on a human signaling network

To investigate signal regulation models of gastric cancer, databases and literature were used to construct the signaling network in humans. Topological characteristics of the network were analyzed by CytoScape. After marking gastric cancer-related genes extracted from the CancerResource, GeneRIF, and COSMIC databases, the FANMOD software was used for the mining of gastric cancer-related motifs in a network with three vertices. The significant motif difference method was adopted to identify significantly different motifs in the normal and cancer states. Finally, we conducted a series of analyses of the significantly different motifs, including gene ontology, function annotation of genes, and model classification. A human signaling network was constructed, with 1643 nodes and 5089 regulating interactions. The network was configured to have the characteristics of other biological networks. There were 57,942 motifs marked with gastric cancer-related genes out of a total of 69,492 motifs, and 264 motifs were selected as significantly different motifs by calculating the significant motif difference (SMD) scores. Genes in significantly different motifs were mainly enriched in functions associated with cancer genesis, such as regulation of cell death, amino acid phosphorylation of proteins, and intracellular signaling cascades. The top five significantly different motifs were mainly cascade and positive feedback types. Almost all genes in the five motifs were cancer related, including EPOR,MAPK14, BCL2L1, KRT18,PTPN6, CASP3, TGFBR2,AR, and CASP7. The development of cancer might be curbed by inhibiting signal transductions upstream and downstream of the selected motifs.

Mortality rate after open Roux-in-Y gastric bypass: a 10-year follow-up

The prevalence of obesity has increased to epidemic status worldwide. Thousands of morbidly obese individuals undergo bariatric surgery for sustained weight loss; however, mid- and long-term outcomes of this surgery are still uncertain. Our objective was to estimate the 10-year mortality rate, and determine risk factors associated with death in young morbidly obese adults who underwent bariatric surgery. All patients who underwent open Roux-in-Y gastric bypass surgery between 2001 and 2010, covered by an insurance company, were analyzed to determine possible associations between risk factors present at the time of surgery and deaths related and unrelated to the surgery. Among the 4344 patients included in the study, 79% were female with a median age of 34.9 years and median body mass index (BMI) of 42 kg/m2. The 30-day and 10-year mortality rates were 0.55 and 3.34%, respectively, and 53.7% of deaths were related to early or late complications following bariatric surgery. Among these, 42.7% of the deaths were due to sepsis and 24.3% to cardiovascular complications. Male gender, age ≥50 years, BMI ≥50 kg/m2, and hypertension significantly increased the hazard for all deaths (P<0.001). Age ≥50 years, BMI ≥50 kg/m2, and surgeon inexperience elevated the hazard of death from causes related to surgery. Male gender and age ≥50 years were the factors associated with increased mortality from death not related to surgery. The overall risk of death after bariatric surgery was quite low, and half of the deaths were related to the surgery. Older patients and superobese patients were at greater risk of surgery-related deaths, as were patients operated on by less experienced surgeons.

Inhibitory effect of liposomal quercetin on acute hepatitis and hepatic fibrosis induced by concanavalin A

Immune response plays an important role in the development of hepatic fibrosis. In the present study, we investigated the effects of quercetin on hepatitis and hepatic fibrosis induced by immunological mechanism. In the acute hepatitis model, quercetin (2.5 mg/kg) was injected iv into mice 30 min after concanavalin A (Con A) challenge. Mice were sacrificed 4 or 24 h after Con A injection, and aminotransferase tests and histopathological sections were performed. Treatment with quercetin significantly decreased the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Consistent with this observation, treatment with quercetin markedly attenuated the pathologic changes in the liver. A hepatic fibrosis model was also generated in mice by Con A challenge once a week for 6 consecutive weeks. Mice in the experimental group were treated with daily iv injections of quercetin (0.5 mg/kg). Histopathological analyses revealed that treatment with quercetin markedly decreased collagen deposition, pseudolobuli development, and hepatic stellate cells activation. We also examined the effects of quercetin on the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and transforming growth factor beta (TGF-β) pathways by immunohistochemistry and real-time reverse transcriptase-polymerase chain reaction (RT-PCR). NF-κB and TGF-β production was decreased after treatment with quercetin, indicating that the antifibrotic effect of quercetin is associated with its ability to modulate NF-κB and TGF-β production. These results suggest that quercetin may be an effective therapeutic strategy in the treatment of patients with liver damage and fibrosis.

PPARγ induces growth inhibition and apoptosis through upregulation of insulin-like growth factor-binding protein-3 in gastric cancer cells

Peroxisome proliferator activator receptor-gamma (PPARγ) is a ligand-activated transcriptional factor involved in the carcinogenesis of various cancers. Insulin-like growth factor-binding protein-3 (IGFBP-3) is a tumor suppressor gene that has anti-apoptotic activity. The purpose of this study was to investigate the anticancer mechanism of PPARγ with respect to IGFBP-3. PPARγ was overexpressed in SNU-668 gastric cancer cells using an adenovirus gene transfer system. The cells in which PPARγ was overexpressed exhibited growth inhibition, induction of apoptosis, and a significant increase in IGFBP-3 expression. We investigated the underlying molecular mechanisms of PPARγ in SNU-668 cells using an IGFBP-3 promoter/luciferase reporter system. Luciferase activity was increased up to 15-fold in PPARγ transfected cells, suggesting that PPARγ may directly interact with IGFBP-3 promoter to induce its expression. Deletion analysis of the IGFBP-3 promoter showed that luciferase activity was markedly reduced in cells without putative p53-binding sites (-Δ1755, -Δ1795). This suggests that the critical PPARγ-response region is located within the p53-binding region of the IGFBP-3 promoter. We further demonstrated an increase in PPARγ-induced luciferase activity even in cells treated with siRNA to silence p53 expression. Taken together, these data suggest that PPARγ exhibits its anticancer effect by increasing IGFBP-3 expression, and that IGFBP-3 is a significant tumor suppressor.

Contractile profile of esophageal and gastric fundus strips in experimental doxorubicin-induced esophageal atresia

Esophageal atresia (EA) is characterized by esophageal and gastric motility changes secondary to developmental and postsurgical damage. This study evaluated the in vitro contractile profile of the distal esophagus and gastric fundus in an experimental model of EA induced by doxorubicin (DOXO). Wistar pregnant rats received DOXO 2.2 mg/kg on the 8th and 9th gestational days. On day 21.5, fetuses were collected, sacrificed, and divided into groups: control, DOXO without EA (DOXO-EA), and DOXO with EA (DOXO+EA). Strips from the distal esophagus and gastric fundus were mounted on a wire myograph and isolated organ-bath system, respectively, and subjected to increasing concentrations of carbamylcholine chloride (carbachol, CCh). The isolated esophagus was also stimulated with increasing concentrations of KCl. In esophagus, the concentration-effect curves were reduced in response to CCh in the DOXO+EA and DOXO-EA groups compared to the control group (P<0.05). The maximum effect values (Emax) for DOXO+EA and DOXO-EA were significantly lower than control (P<0.05), but the half-maximal effective concentration (EC50) values were not significantly different when the three groups were compared (P>0.05). In response to KCl, the distal esophagus samples in the three groups were not statistically different with regard to Emax or EC50 values (P>0.05). No significant difference was noted for EC50 or Emax values in fundic strips stimulated with CCh (P>0.05). In conclusion, exposure of dams to DOXO during gestation inhibited the contractile behavior of esophageal strips from offspring in response to CCh but not KCl, regardless of EA induction. The gastric fundus of DOXO-exposed offspring did not have altered contractile responsiveness to cholinergic stimulation.

Correlation of cadherin-17 protein expression with clinicopathological features and prognosis of patients with sporadic gastric cancer

This study aimed to explore the correlations between cadherin-17 (CDH17) protein expression and the clinicopathological features and prognosis of patients with sporadic gastric cancer (GC). Nine relevant studies of 1,960 patients were identified using electronic database searches supplemented with a manual search in strict accordance with inclusion and exclusion criteria. Statistical analyses were conducted using STATA 12.0 statistical software. Relative risks and 95% confidence intervals were determined, and Z test was used to measure the significance of the overall effect size. A total of nine eligible cohort studies were included in this meta-analysis. The expression of CDH17 in patients with diffuse GC was significantly higher than in those with intestinal-type GC. Moreover, the tumor depth of invasion differed significantly between patients with positive CDH17 (CDH17+) and negative CDH17 (CDH17-) GC. However, there were no significant differences between CDH17+ and CDH17- GC patients with respect to tumor node metastasis clinical stages, histological grades, or lymph node metastasis. Despite the differences in invasive depth, there was no significant difference in 5-year survival rates between CDH17+ and CDH17- GC patients. Our meta-analysis provides evidence that CDH17 protein expression may be associated with the development of GC, suggesting that CDH17 is an important biomarker that could be useful for the early diagnosis of GC. However, CDH17 levels do not appear to impact overall survival.

β-Citronellol, an alcoholic monoterpene with inhibitory properties on the contractility of rat trachea

β-Citronellol is an alcoholic monoterpene found in essential oils such Cymbopogon citratus (a plant with antihypertensive properties). β-Citronellol can act against pathogenic microorganisms that affect airways and, in virtue of the popular use of β-citronellol-enriched essential oils in aromatherapy, we assessed its pharmacologic effects on the contractility of rat trachea. Contractions of isolated tracheal rings were recorded isometrically through a force transducer connected to a data-acquisition device. β-Citronellol relaxed sustained contractions induced by acetylcholine or high extracellular potassium, but half-maximal inhibitory concentrations (IC50) for K+-elicited stimuli were smaller than those for cholinergic contractions. It also inhibited contractions induced by electrical field stimulation or sodium orthovanadate with pharmacologic potency equivalent to that seen against acetylcholine-induced contractions. When contractions were evoked by selective recruitment of Ca2+ from the extracellular medium, β-citronellol preferentially inhibited contractions that involved voltage-operated (but not receptor-operated) pathways. β-Citronellol (but not verapamil) inhibited contractions induced by restoration of external Ca2+ levels after depleting internal Ca2+ stores with the concomitant presence of thapsigargin and recurrent challenge with acetylcholine. Treatment of tracheal rings with L-NAME, indomethacin or tetraethylammonium did not change the relaxing effects of β-citronellol. Inhibition of transient receptor potential vanilloid subtype 1 (TRPV1) or transient receptor potential ankyrin 1 (TRPA1) receptors with selective antagonists caused no change in the effects of β-citronellol. In conclusion, β-citronellol exerted inhibitory effects on rat tracheal rings, with predominant effects on contractions that recruit Ca2+ inflow towards the cytosol by voltage-gated pathways, whereas it appears less active against contractions elicited by receptor-operated Ca2+ channels.