Mesenchymal stem cells can improve anal pressures after anal sphincter injury

Objective.Fecal incontinence reduces the quality of life of many women but has no long-term cure. Research on mesenchymal stem cell (MSC)-based therapies has shown promising results. The primary aim of this study was to evaluate functional recovery after treatment with MSCs in two animal models of anal sphincter injury.Methods.Seventy virgin female rats received a sphincterotomy (SP) to model episiotomy, a pudendal nerve crush (PNC) to model the nerve injuries of childbirth, a sham SP, or a sham PNC. Anal sphincter pressures and electromyography (EMG) were recorded after injury but before treatment and 10 days after injury. Twenty-four hours after injury, each animal received either 0.2 ml saline or 2 million MSCs labelled with green fluorescing protein (GFP) suspended in 0.2 ml saline, either intravenously (IV) into the tail vein or intramuscularly (IM) into the anal sphincter.Results.MSCs delivered IV after SP resulted in a significant increase in resting anal sphincter pressure and peak pressure, as well as anal sphincter EMG amplitude and frequency 10 days after injury. MSCs delivered IM after SP resulted in a significant increase in resting anal sphincter pressure and anal sphincter EMG frequency but not amplitude. There was no improvement in anal sphincter pressure or EMG with in animals receiving MSCs after PNC. GFP-labelled cells were not found near the external anal sphincter in MSC-treated animals after SP.Conclusion.MSC treatment resulted in significant improvement in anal pressures after SP but not after PNC, suggesting that MSCs could be utilized to facilitate recovery after anal sphincter injury.     

Adaptation of rat gastric tissue against indomethacin toxicity

Indomethacin is used in the treatment of inflammatory diseases. But the drug toxicity limits its usage. This study investigated whether adaptation occurred after various dosages of repeated (chronic) indomethacin in rats to the gastro-toxic effects of indomethacin. It also examined whether the adaptation was related to oxidant–antioxidant mechanisms and oxidative DNA damage in gastric tissue. To illuminate the adaptation mechanism in the gastric tissue of rats given various dosages of chronic indomethacin, the levels of oxidants and antioxidants (GSH, MDA, NO, SOD and MPO), activities of COX-1 and COX-2 enzymes and oxidative DNA damage (8-OHd Gua/10⁵ Gua) were measured. Results were compared to 25-mg/kg single-dose indomethacin group, and the role of oxidant and antioxidant parameters and oxidative DNA damage in the adaptation mechanism was evaluated. The average ulcer areas of gastric tissue of the 0.5-, 1-, 2-, 3-, 4-, and 5-mg/kg dosages of chronic indomethacin given to rats were 19.5 ± 3.7, 12.5 ± 3.3, 10 ± 5.2, 4.5 ± 3.6, 8.6 ± 2.4, and 9.5 ± 2.1 mm², respectively. This rate was measured as 21.3 ± 2.6 mm² in the single-dose indomethacin group. Consequently, after various dosages of repeated (chronic) indomethacin administration in rats, it was observed that a clear adaptation developed against gastric damage and that gastric damage was reduced. The best adaptation was observed in the gastric tissue of the 3-mg/kg chronic indomethacin group. In parallel with the damage reduction, the oxidant parameters (MDA and MPO) and oxidative DNA damage (8-OHd Gua/10⁵ Gua) were reduced, and the antioxidant parameters (GSH, NO and SOD) were increased. There is no relation between COX enzymes and adaptation mechanism. This circumstance shows that not COX-1 and COX-2 enzymes, oxidant and antioxidant parameters may play a role in the adaptation mechanism.     

Engineering microdent structures of bone implant surfaces to enhance osteogenic activity in MSCs

Problems persist with the integration of hip and dental implants with host bone tissues, which may result in long-term implant failure. Previous studies have found that implants bearing irregular surfaces can facilitate osseointegration. An improvement to this approach would use implant surfaces harboring a well-defined surface microstructure to decrease variability in implant surfaces. In this study, we tested whether well-defined surfaces with arrays of microdents (each with depth approximately 3 µm) significantly affected the morphology, proliferation, and osteogenic activity of mesenchymal stem cells (MSCs). Arrays of microdents tested had diameters of 9 µm, 12 µm, and 18 µm, while spacing between arrays ranged from 8 µm to 34 µm. Effects on MSC morphology (cell spreading area) and proliferation were also quantified, with both significantly decreasing on micropatterned surfaces (p<0.05) on smaller and denser microdents. In contrast, MSCs were found to deposit more calcified matrix on smaller and denser arrays of microdents. MSCs on a pattern with arrays of microdents with a diameter of 9 µm and a spacing 8 µm deposited 3–4 times more calcified matrix than on a smooth surface (p<0.05). These findings show that well-defined surface microtopographies promote osteogenic activity, which can be used on implant surfaces to improve integration with the host bone tissue.     

Effect of Astragalus polysaccharides on expression of TNF-α, IL-1β and NFATc4 in a rat model of experimental colitis

AimAstragalus membranaceus is a Chinese medicinal herb and has been shown to improve hapten-induced experimental colitis. One of its major components is polysaccharides. We investigated the effect of Astragalus polysaccharides (APS) on expression of TNF-α, IL-1β and NFATc4 in a rat model of experimental colitis.MethodsThe experimental colitis model was induced by TNBS. Forty five rats were divided into five groups (n = 9): Normal control group, receiving ethanol vehicle with no TNBS during induction and IP saline injection during treatment; TNBS colitis model group (TNBS + IP saline), receiving only IP saline vehicle treatment; APS low dose group (TNBS + L-APS), receiving APS 100 mg/kg; APS high dose group (TNBS + H-APS), receiving APS 200 mg/kg; and positive control group (TNBS + Dexm), receiving dexamethasone 0.3 mg/kg. The clinical features, macroscopic and microscopic scores were assessed. The expressions of TNF-α, IL-1β and NFATc4 were measured by real-time PCR and ELISA assays.ResultsCompared to normal control rats, TNBS + IP saline had significant weight loss, increased macroscopic and microscopic scores, higher disease activity index (DAI) up-regulation of TNF-α, IL-1β and NFATc4 mRNA expression and up-regulation of TNF-α and IL-1β protein expression. Compared to TNBS + IP saline, treatment with APS or dexamethasone significantly reduced DAI, partially but significantly prevented TNBS colitis-induced weight loss and improved both macroscopic and microscopic scores; high dose APS or dexamethasone significantly down-regulated TNF-α and IL-1β expressions (both mRNA and protein) and up-regulated NFATc4 mRNA and protein expression. The effect of high dose APS and dexamethasone is comparable.ConclusionsAPS significantly improved experimental TNBS-induced colitis in rats through regulation of TNF-α, IL-1β and NFATc4 expression.     

Mechanical stress regulates osteogenic differentiation and RANKL/OPG ratio in periodontal ligament stem cells by the Wnt/β-catenin pathway

BackgroundThe balance between osteoblastic and osteoclastic activity is critical in orthodontic tooth movement (OTM). Mesenchymal stem cells (MSCs) play an important role in maintaining bone homeostasis, and periodontal ligament stem cells (PDLSCs) are tissue-specific MSCs in the periodontal ligament. However, whether PDLSCs are required for periodontal tissue remodeling during OTM is not fully understood.MethodsHere, we used PDGFRα and Nestin to trace PDLSCs during OTM in rats. We treat human PDLSCs with 100 kpa static pressure for 1 h or 12 h in vitro, and examined the phenotypic changes and expression of RANKL and OPG in these cells.ResultsIn vivo, we found that positive signals of PDGFRα and Nestin in the PDL gradually increased and then decreased on the pressure side to which pressure was applied. In vitro, the osteogenic differentiation of PDLSCs was significantly increased after force treatment for 1 h relative to 12 h. In contrast, the expression ratio of RANKL/OPG was reduced at 1 h and significantly increased at 12 h. Furthermore, we found that the Wnt/β-catenin pathway was dynamically activated in the PDL and in PDLSCs after mechanical stimulation. Importantly, the canonical Wnt pathway inhibitor DKK1 blocked the osteogenesis effect and rescued the ratio of RANKL/OPG in PDLSCs under force treatment for 1 h.ConclusionsOur findings reveal that PDLSCs participate in OTM and that the Wnt/β-catenin pathway maintains bone homeostasis during tooth movement by regulating the balance between osteoblastic and osteoclastic activity.General significanceWe describe a novel potential mechanism related to tooth movement.     

Combined Wharton’s jelly derived mesenchymal stem cells and nerve guidance conduit: A potential promising therapy for peripheral nerve injuries

BackgroundPeripheral nerve injuries represent a clinical problem with insufficient or unsatisfactory treatment options. Functional outcome with nerve guidance conduits was unsatisfactory in nerve defects with increased gap size. So, cell therapy may benefit as a tool for optimizing the regeneration process. The aim of the present study was to evaluate the impact of combination of cell therapy and nerve guidance conduits on the nerve regeneration and on the expression of the factors aiding the regeneration in a rat model of sciatic nerve injury.Methods and resultsSixty Wistar rats were randomly divided into four groups: Group I: normal control group; Group II: sciatic nerve injury (SNI) with a 10 mm long sciatic nerve gap; Group III: SNI with using a nerve conduit (NC) for nerve gap bridging; and Group IV: SNI with using a NC associated with Wharton’s jelly derived mesenchymal stem cells (WJ-MSCs). The results showed that the combination therapy NC + WJ-MSCs caused much better beneficial effects than NC alone evidenced by increasing sciatic nerve index and pin-prick score. The histopathological analysis found that the use of the NC combined with WJ[HYPHEN]MSCs resulted in a structure of the sciatic nerve comparable to the normal one with better nerve regeneration when compared with NC only. There was no differentiation of WJ-MSCs into nerve structure. Lastly, there was an upregulation of expression for netrin-1, ninjurin, BDNF, GDNF, VEGF and angiopoitin-1 rat genes in NC + WJ-MSCs group than NC alone.ConclusionThe addition of WJ-MSCs to the nerve guidance conduits seems to bring significant advantage for nerve regeneration, basically by increasing the expression of neurotrophic and angiogenic factors establishing more favorable environment for nerve regeneration.     

Endothelium oriented differentiation of bone marrow mesenchymal stem cells under chemical and mechanical stimulations

Bone marrow mesenchymal stem cells (MSCs) have multi-differentiation capability. Their endothelial cell (EC) oriented differentiation is the key to vasculogenesis, in which both mechanical and chemical stimulations play important roles. Most previous studies reported individual effects of VEGF or fluid shear stress (SS), when MSCs were subjected to shear stress of 10–15 dyn/cm² over 24 hr. In this paper, we investigated responses of MSCs from young Sprague Dawley rats to shear stress, VEGF and the combination of the two stimuli. Our study showed that the combined stimulation of shear stress and VEGF resulted in more profound EC oriented differentiation of MSCs in comparison to any individual stimulation. Furthermore, we subjected MSCs to prolonged period of fluid shear stimulation, i.e. 48 hr rather than 24 hr, and increased the magnitude of the shear stress from 10 dyn/cm² to 15, 20 and 25 dyn/cm². We found that without VEGF, the endothelium oriented differentiation of MSCs that was seen following 24 hr of shear stimulation was largely abolished if we extended the shear stimulation to 48 hr. A similar sharp decrease in MSC differentiation was also observed when the magnitude of the shear stress was increased from 10–15 dyn/cm² to 20–25 dyn/cm² in 24 hr shear stimulation studies. However, with combined VEGF and fluid shear stimulation, most of the endothelial differentiation was retained following an extended period, i.e. at 48 hr, of shear stimulation. Our study demonstrates that chemical and mechanical stimulations work together in determining MSC differentiation dynamics.     

Effects of cefaclor on gastric emptying and cholecystokinin release in healthy humans

Background and aimsIn rodents, cephalosporin antibiotics can mimic peptones and stimulate release of cholecystokinin (CCK), a hormone that slows gastric emptying. The rate of gastric emptying is a major determinant of postprandial blood glucose and insulin concentrations. We therefore evaluated the effect of orally administered cefaclor on plasma CCK and gastric emptying, as well as postprandial glycemic and insulinemic responses, in healthy humans.Materials and methodsWe studied 8 healthy subjects on two days in double-blind, randomized order. On each day, subjects consumed 1000 mg cefaclor or placebo 30 min before a mashed potato meal labeled with ¹³C octanoic acid. Blood and breath samples were collected for 4 h after the meal.ResultsBlood glucose, serum insulin and plasma CCK increased in response to the carbohydrate meal on both study days, and cefaclor had no effect on these responses. Similarly, the gastric half-emptying time (measured by breath test) did not differ (placebo: 137.5 ± 6.0 min vs. cefaclor: 143.1 ± 8.0 min).ConclusionCefaclor, when given before a meal in the form of a capsule, does not stimulate CCK release or slow gastric emptying in healthy humans.     

Correlation between cell attachment areas after 2 h of culture and osteogenic differentiation activity of rat mesenchymal stem cells on hydroxyapatite substrates with various surface properties

The initial attachment of mesenchymal stem cells (MSCs) to substrates and osteogenic differentiation are supported by culture on a hydroxyapatite substrate. Cell attachment areas of rat MSCs after 2 h of culture on hydroxyapatite substrates with various microstructures and the osteogenic differentiation activity thereafter were measured. The perceived outcome was that, after 2 h of culture, rat MSCs with a small attachment area would have a high osteogenic differentiation activity, whereas those with a large attachment area would have a low osteogenic differentiation activity. Furthermore, rat MSCs with a small attachment area had many cytoplasmic processes, while those with a large attachment area revealed clear stress fibers and focal contacts. These results suggest that cell attachment area of rat MSCs after 2 h of culture has a strong effect on the osteogenic differentiation of rat MSCs. Thus, the measurement of cell attachment area after 2 h of culture could become valuable for estimating the osteogenic differentiation activity of rat MSCs thereafter.     

Association between TNF-α-308 G/A gene polymorphism and gastric cancer risk: A systematic review and meta-analysis

ObjectiveTumor necrosis factor-alpha (TNF-α) has been found to be associated with gastric carcinogenesis, but individually published results have been inconclusive. The aim of this study was to explore the relationship between the TNF-α-308 G/A polymorphism and gastric cancer risk.MethodsMEDLINE, EMBASE and the COCHRANE library databases were searched for relevant articles to identify all available data. The odds ratios (ORs) with 95% confidence intervals (95% CIs) from each study were used to assess the association between the TNF-α-308 G/A polymorphism and gastric cancer risk.ResultsThis meta-analysis included 30 studies (32 datasets) involving 7009 gastric cancer cases and 12,119 control subjects. Overall, a significant association was found between the TNF-α-308 G/A polymorphism and gastric cancer in AA + GA vs. GG (dominant contrast model) (OR = 1.20, 95% CI = 1.07–1.34, p = 0.001). With stratification based on ethnicity, the TNF-α-308 G/A polymorphism was correlated with gastric cancer risk in Caucasians, using the dominant contrast model (OR = 0.74, 95% CI = 0.57–0.96, p = 0.02), but not in East Asians and other ethnic groups. In the comprehensive subgroup analysis, a significant association was also found in recent articles (published after 2005), population-based high-quality studies, hospital-based high-quality studies, studies using the TaqMan method and non-cardia subgroups. However, the TNF-α-308 G/A polymorphism was not associated with specific histological types of gastric cancer risk.ConclusionsThe TNF-α-308 G/A polymorphism may contribute to susceptibility to gastric cancer in Caucasians, especially for non-cardia gastric cancer, as most strongly demonstrated in high-quality studies and in studies using the TaqMan genotyping method. Furthermore, we recommend the TaqMan method as the preferred genotyping method in DNA polymorphism studies.     

Cellular and molecular mechanisms of 17β-estradiol postconditioning protection against gastric mucosal injury induced by ischemia/reperfusion in rats

AimsTo investigate the protective effects of 17β-estradiol postconditioning against ischemia/reperfusion (I–R)-induced gastric mucosal injury in rats.Main methodsThe animal model of gastric ischemia/reperfusion was established by clamping of the celiac artery for 30 min and reperfusion for 30 min, 1 h, 3 h, 6 h, 12 h or 24 h. 17β-estradiol at doses of 5, 50 or 100 μg/kg (rat) was administered via peripheral veins 2 min before reperfusion. In a subgroup of rats, the estrogen receptor antagonist fulvestrant (Ful, 2 mg/kg) was intravenously injected prior to 17β-estradiol administration. Histological and immunohistochemical methods were employed to assess the gastric mucosal injury index and gastric mucosal cell apoptosis and proliferation. The malondialdehyde (MDA) concentration, superoxide dismutase (SOD) activity, xanthine oxidase (XOD) activity and hydroxyl free radical (–OH) inhibitory ability were determined by colorimetric assays. Subsequently, the expression of Bcl-2 and Bax in rat gastric mucosa was examined by western blotting.Key findings17β-estradiol dose-dependently inhibited gastric I–R (GI–R) injury, and 17β-estradiol (50 μg/kg) markedly attenuated GI–R injury 1 h after reperfusion. 17β-estradiol inhibited gastric mucosal cell apoptosis and promoted gastric mucosal cell proliferation in addition to increasing SOD activity and –OH inhibitory ability and decreasing the MDA content and XOD activity. The Bax protein level increased 1 h after GI–R and was markedly reduced by intravenous administration of 17β-estradiol. In contrast, the level of Bcl-2 protein decreased 1 h after GI–R and was restored to normal levels by intravenous administration of 17β-estradiol. These effects of 17β-estradiol were inhibited by pretreatment with fulvestrant.Significance17β-estradiol postconditioning should be investigated further as a possible strategy against gastric mucosal injury.     

Influencia del inmunoensayo empleado en la determinación de vitamina D sérica

IntroductionSerum 25-hydroxyvitamin D [25(OH)D] levels are the best indicator of vitamin D levels in the body. Precision, reproducibility, and lack of standardization are the main problems in such measurements. The aim of this study was to compare the 25(OH)D levels measured using Elecsys Vitamin D Total (Roche) and ADVIA Centaur Vitamin D Total (Siemens).Material and methods25(OH)D levels were tested in 166 patients using both methods. Patients were subsequently divided into two groups: a «supplemented group» consisting of patients receiving vitamin D supplements, and an «untreated group» consisting of the rest of patients.Results25(OH)D mean levels measured by the Roche and Siemens methods in the overall group were 33.6 ± 16.0 and 19.8 ± 12.4 ng/mL respectively. 54.2% of patients were receiving vitamin D supplements. In this group, mean 25(OH)D levels measured by the Roche and Siemens methods were 40.6 ± 14.5 and 25.4 ± 13.1 ng/mL respectively. In the untreated group, the respective values were 24.9 ± 13.2 and 12.8 ± 6.6 ng/mL. Prevalence of vitamin D deficiency (serum 25(OH)D levels less than 20 ng/mL) was higher in samples analyzed using the Siemens method (60.2%) as compared to those tested using the Roche method (23.5%).ConclusionThe assays evaluated are not comparable to each other. Laboratory specialists should inform clinicians of the features of the method used for measuring 25(OH)D because this will have a direct impact on interpretation of the results and medical decisions.     

Migration mechanism of mesenchymal stem cells studied by QD/NSOM

The migration of mesenchymal stem cells (MSCs) plays a key role in tumor-targeted delivery vehicles and tumor-related stroma formation. However, there so far has been no report on the distribution of cell surface molecules during the VEGF-induced migration of MSCs. Here, we have utilized near-field scanning optical microscopy (NSOM) combined with fluorescent quantum dot (QD)-based nano-technology to capture the functional relationship between CD44 and CD29 adhesion molecules on MSCs and the effect of their spatial rearrangements. Before VEGF-induced migration of MSCs, both CD44 and CD29 formed 200–220 nm nano-domains respectively, with little co-localization between the two types of domains. Surprisingly, the size of the CD44 nano-domain rapidly increased in size to 295 nm and apparently larger aggregates were formed following MSC treatment with VEGF for 10 min, while the area of co-localization increased to 0.327 μm². Compared with CD44, CD29 was activated obviously later, for the fact that CD29 aggregation didn't appear until 30 min after VEGF treatment. Consistently, its co-localization area increased to 0.917 μm². The CD44 and CD29 nano-domains further aggregated into larger nano-domains or even formed micro-domains on the membrane of activated MSCs. The aggregation and co-localization of these molecules promoted FAK formation and cytoskeleton rearrangement. All of the above changes induced by VEGF contributed to MSC migration. Taken together, our data of NSOM-based dual color fluorescent imaging demonstrated for the first time that CD44, together with CD29, involved in VEGF-induced migration of MSCs through the interaction between CD44 and its co-receptor of VEGFR-2.     

Polymorphisms of tumor-related genes IL-10, PSCA,MTRR and NOC3L are associated with the risk of gastric cancer in the Chinese Han population

BackgroundGastric cancer is the fourth most common cancer in the world. Environmental and genetic factors both play critical roles in the etiology of gastric cancer. Hundreds of SNPs have been identified to have association with the risk of gastric cancer in many races. In this study, 25 SNPs in genes for IL-10, IL-1B, MTRR, TNF-а, PSCA, PLCE1 and NOC3L were analyzed to further evaluate their associations with gastric cancer susceptibility in the Chinese Han population.MethodsTwo hundred and seventy nine gastric cancer patients and 296 healthy controls were recruited in this study. SNP genotyping was conducted using Sequenom MassARRAY RS1000. Data management and statistical analyses were conducted by Sequenom Typer 4.0 Software and Pearson's χ² test.ResultsOne protective allele and three risk alleles for gastric cancer patients were found in this study. The allele “G” of rs1801394 in MTRR showed an association with a decreased risk of gastric cancer: odds ratio (OR) = 0.74, 95% confidence interval (95% CI) = 0.57–0.97, P = 0.030 in the additive model; OR = 0.495, 95% CI = 0.26–0.95, P = 0.034 in the recessive model. The other three SNPs, the allele “C” of rs1800871 in IL10 (OR = 1.33, 95% CI = 1.04–1.90; P = 0.026 in the additive model; OR = 1.46, 95% CI = 1.04–2.06; P = 0.030 in the recessive model), the allele “A” of rs2976391 in PSCA (OR = 1.30, 95% CI = 1.01–1.66; P = 0.041 in the additive model and OR = 1.48, 95% CI = 1.04–2.11, P = 0.028 in the recessive model), and the allele “G” of rs17109928 in NOC3L gene (OR = 1.34, 95% CI = 1.01–1.78; P = 0.042 by additive model analysis; OR = 1.47, 95% CI = 1.04–2.07, P = 0.028 by dominant model analysis), showed an association with an increased risk of gastric cancer.ConclusionsThese results indicate the importance of four gastric cancer susceptibility polymorphisms of IL-10, NOC3L, PSCA and MTRR in the Chinese Han population, which could be used in the determination of gastric cancer risk in clinical practice.     

CXC chemokine CXCL12 tissue expression and circulating levels in peptic ulcer patients with Helicobacter pylori infection

Helicobacter pylori (H. pylori) infection is among the most prevalent human infections. CXCL12 is a well-known CXC chemokine involved in inflammation and play major roles in angiogenesis. There is currently very limited data on the role of CXCL12 in peptic ulcer disease. Hence, we aimed to explore whether CXCL12 is involved in the pathogenesis of peptic ulcer induced by H. pylori. In this study, we enrolled 102 H. pylori-infected patients, including 51 with active ulcer (GA) and 51 with healing ulcer (GH). We also recruited 50 healthy subjects as control, which did not show any sign or symptoms of chronic inflammatory diseases, infection, or immune-related disorders. Endoscopy was performed to determine the stage of the disease. ELISA was used for detection of H. pylori infection and CXCL12 measurement. We also employed western blotting to detect CXCL12 in ulcerative lesions of H. pylori. Demographic data were also collected by questionnaire. Our results demonstrated that CXCL12 serum levels in GA group (151.8 ± 18.31 pg/mL) were significantly higher than those in GH (36.89 ± 6.78 pg/mL) and control groups (33.77 ± 9.12 pg/mL) (P < 0.0001). However, we did not observe a significant difference between GH and control groups. Moreover, overexpression of CXCL12 in gastric lesions of patients in GA group was confirmed by Western blot analysis. According to the result of the present study, it could be concluded that CXCL12 is involved in the pathogenesis and healing of H. pylori-induced peptic ulcer. CXCL12 serum levels may also be used to distinguish between GA and GH phases of the disease.     

dl-trans-3,4-Dihydroxy-1-selenolane (DHSred) heals indomethacin-mediated gastric ulcer in mice by modulating arginine metabolism

BackgroundThe importance of the arginine metabolism in gastric ulcer-healing is given relatively less attention. Hence the role of controlling this pathway by dl-trans-3,4-dihydroxy-1-selenolane (DHS_red) and omeprazole against indomethacin-induced stomach ulceration in mouse was investigated.MethodsSwiss albino mice were ulcerated with indomethacin followed by treatment with the test samples, and the activities of myeloperoxidase (MPO), total nitric oxide synthase (NOS) and arginase, the expressions of inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS), and the pro-/anti-inflammatory cytokine levels were assayed. NOS-inhibitors were also used to establish the biochemical mechanism.ResultsIndomethacin induced maximum ulceration in mice on the 3rd day, associated with reduced arginase activity, eNOS expression, along with increased MPO and total NOS activities, nitric oxide (NO) generation, iNOS expression, and pro-/anti-inflammatory (Th₁/Th₂₎ cytokine ratio. Treatment with DHS_red (2.5 mg kg^− 1 × 3 days) restored the cytokine balance to shift the iNOS/NO axis to the arginase/polyamine axis as revealed from the increased arginase activity and eNOS expression, and reduced iNOS expression, total NOS activity and NO level.ConclusionsThe ulcer-healing property of DHS_red, but not of omeprazole was due to a favorable pro-/anti-inflammatory cytokine ratio that shifted the arginine metabolism to the polyamine pathway and increased the eNOS/iNOS ratio. The healing action of omeprazole was not significantly associated with these parameters.General significanceThe shift in the ariginine-metabolism from the iNOS/NO axis to the arginase/polyamine axis is guided by Th_1/Th₂ cytokines ratio and plays an important role in gastric ulcer-healing. The favourable effects of the non-toxic and water-soluble compound, DHS_red on these pathways and other COX-dependent and antioxidative parameters suggested it to be a promising anti-ulcer formulation for further studies.     

Alkaloids from Mahonia bealei posses anti-H+/K+-ATPase and anti-gastrin effects on pyloric ligation-induced gastric ulcer in rats

The purpose of this study was to investigate the underlying mechanism(s) of the total alkaloids (TA) from Mahonia bealei in treating pyloric ligation-induced gastric ulcers in rats. Animals were sacrificed after 19 h of the ligation. Gastric acid, peptic activities, mucin levels, H⁺/K⁺-ATPase activities and the gastrin level were analyzed. To improve the accuracy of the observations, IPP 6.0 software was introduced to measure the area of ulcer. TA (18.56 mg/kg/day, i.g.) showed an antiulcer effect by significantly decreasing the gastric ulcer areas (11.28 mm²) compared with model group (26.36 mm²). The TA ulcer inhibition ratio was 57.2%, compared with the effect of the positive control, omeprazole (62.96%). The results also showed that TA had a significant effect in inhibiting the release of H⁺/K⁺-ATPase, reducing the content of gastrin and decreasing gastric acidity on experimental animals. However, the TA had no significant effects on gastric mucus secretion and pepsin activity. Data indicated that TA had gastric ulcer protective effects by modulating the H⁺/K⁺-ATPase activity and gastrin level. TA has a potential to be developed as a pharmacological agent for the treatment of gastric ulcers.     

The clonogenic potential of hematopoietic stem cells and mesenchymal stromal cells in various hematologic diseases: a pilot study

Background aimsMesenchymal stromal cells (MSC) are the most popular cells used in regenerative medicine and biotechnology. The clonogenic potential of these cells is defined by colony-forming unit-fibroblasts (CFU-F). It is well known that there is an interaction between hematopoietic cells and stromal cells in disease formation pathogenesis. Therefore we hypothesized that there should be a quantitative and qualitative relationship between MSC colonies (CFU-F) and hematopoietic stem cell colonies (colony-forming unit-granulocyte-macrophages; CFU-GM) among patients with and without hematologic diseases.MethodsForty-two patients were included in this study. Patients were divided into three groups: group A, patients with hematologic malignancies (n = 20); group B, patients with bone marrow (BM) failure (n = 11); group C, patients without hematologic diseases (n = 11). BM aspirates were plated in different densities for CFU-F culture. The plating density was the same for CFU-GM culture.ResultsCFU-GM colonies grew in 90% of group A cells and all of group B and C cells (P = 0.0001). CFU-F colonies became visible on the ninth day of plating in group A and on the eight day in groups B and C. There was no statistically significant difference between the groups for the duration of CFU-F colony formation (P = 0.12). There were differences in the morphology of the colonies among the groups.ConclusionsThis is the first study that has compared the clonogenic potential of stromal cells and hematopoietic stem cells in the same subjects with and without hematologic diseases. No correlation was shown between the clonogenic potential of stromal cells and hematopoietic cells.     

Transforming growth factor beta 1 (TGF-β1) modulates Epstein-Barr virus reactivation in absence of Helicobacter pylori infection in patients with gastric cancer

BackgroundTransforming growth factor-beta 1 (TGF-β1), a multifunctional cytokine, acts as a key factor for Epstein-Barr virus (EBV) reactivation. We investigated the role of TGF-β1 in latent and lytic stages of EBV in relation to Helicobacter pylori infection among patients with gastric cancer (GC) and peptic ulcer disease (PUD).MethodGastric mucosal TGF-β1 expression was determined in 95 EBV positive patients with gastroduodenal pathology [GC 40, PUD 19 and non-ulcer dyspepsia (NUD) 36] by quantitative real time PCR. Presence of H. pylori infection was diagnosed when either culture or any two of three tests (RUT, histopathology and specific ureA PCR) were positive. Serum level of TGF-β1 was detected among 60 patients using ELISA.ResultsMucosal TGF-β1 mRNA expression was detected in 85 of 95 EBV positive patients and it was significantly higher in patients with GC (p = 0.042). TGF-β1 expression tended to be higher among H. pylori non-infected than infected patients (3.80 ± 6.24 vs. 2.07 ± 2.50, p = 0.085). Both mRNA and serum level had significant association with lytic stage of EBV in absence of H. pylori infection when compared with its presence (5.21 ± 4.00 vs. 2.29 ± 2.89, p = 0.040 and 842.00 [669.55] vs. 662.63 [628.76], p = 0.049; respectively).ConclusionTGF-β1 expression was significantly associated with GC. TGF-β1 was higher both at expression and translational levels in lytic EBV infection without H. pylori suggests that H. pylori infection might play important role in preventing EBV reactivation through attenuated TGF-β1 expression. This might be a “wise host defense against EBV reactivation”.