Polymorphisms of the TLR4 gene and risk of gastric cancer

Objective

Toll-like receptor 4 (TLR4) is an important lipo-polysaccharide (LPS) receptor in gastric epithelial cell signaling transduction and plays critical roles in the development and progression of gastric cancer (GC). We investigated the effects of TLR4 gene polymorphisms and gene–environmental interactions on the risk of GC in Northeastern China.

Methods

We genotyped two single-nucleotide polymorphisms (SNPs) in TLR4 (rs10116253 and rs1927911) in 217 GC patients and 294 cancer-free controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Odds ratio (OR) and 95% confidence intervals (CIs) were estimated by unconditional logistic-regression models.

Results

Individuals carrying CC genotype of rs10116253 and TT genotype of rs1927911 had a significantly decreased risk of GC (adjusted OR = 0.33, 95% CI 0.18–0.60, P < 0.001 and adjusted OR = 0.37, 95% CI 0.21–0.67, P = 0.001 respectively), compared with TT genotype of rs10116253 and CC genotype of rs1927911. In addition, the SNP effects were additive to the effects of some known environmental factors without any interaction between them in the susceptibility to GC.

Conclusion

Our data suggested that TLR4 gene polymorphisms may be associated with a decreased risk of GC in Chinese population. And these SNPs and their combined effects with environmental factors may be associated with the risk of GC.     

Antinociceptive,anti-inflammatory and antipyretic effects of 1.5-diphenyl-1H-Pyrazole-3-carbohydrazide,a new heterocyclic pyrazole derivative

Aims

Heterocyclic pyrazole derivative has been described for the treatment of pain and inflammatory diseases. This study evaluated the in vivo, antinociceptive, anti-inflammatory and antipyretic effects of 1.5-diphenyl-1H-Pyrazole-3-carbohydrazide (1.5-DHP) and the in vivo or in vitro mechanism of action.

Main methods

Acetic acid-induced writhing, hot-plate and formalin-induced nociception tests were used to evaluate the antinociceptive effect, while the rota-rod test was used to assess the motor activity. Croton oil-induced ear edema and carrageenan-induced peritonitis tests were used to investigate the anti-inflammatory effect of 1.5-DHP. The antipyretic effect was assessed using the LPS-induced fever model. The mechanism of action was evaluated by PGE₂ and TNF-α measurement and cyclooxygenase inhibition assay.

Key findings

Oral administration (p.o.) of 1.5-DHP (1, 3, 10 mg/kg) caused a dose-related inhibition of the acetic acid-induced writhing, however the highest dose was not effective on the hot-plate and rota-rod. In the formalin-induced nociception, 1.5-DHP (10 mg/kg, p.o.) inhibited only the late phase of nociception. This same dose of 1.5-DHP also reduced the croton oil-induced ear edema. 1.5-DHP (3, 10, 30 mg/kg, p.o.) produced a dose-related reduction of leukocyte migration on the carrageenan-induced peritonitis. 1.5-DHP (60 mg/kg, p.o.) reduced the fever and the increase of PGE₂ concentration in the cerebrospinal fluid induced by LPS. 1.5-DHP inhibited both COXs in vitro. Finally, 1.5-DHP (10 mg/kg, p.o.) reduced the TNF-α concentration in peritoneal exudates after carrageenan injection.

Significance

These results indicate that 1.5-DHP produces anti-inflammatory, antinociceptive and antipyretic effects by PGE₂ synthesis reduction through COX-1/COX-2 inhibition and by TNF-α synthesis/release inhibition.     

Evasion from accelerated blood clearance of nanocarrier named as “Lactosome” induced by excessive administration of Lactosome

Background

Nanoparticle of Lactosome, which is composed of poly(l-lactic acid)-base depsipeptide with diameter of 35 nm, accumulates in solid tumors by the enhanced permeability and retention (EPR) effect. However, a pharmacokinetic alteration of Lactosome was observed when Lactosome was repeatedly administered. This phenomenon is named as the Lactosome accelerated blood clearance (ABC) phenomenon. In this study, the effect of Lactosome dose on the ABC phenomenon was examined and discussed in terms of immune tolerance.

Methods

To tumor transplanted mice, Lactosome (0–350 mg/kg) was administrated. At 7 days after the first administration, indocyanine green (ICG)-labeled Lactosome (ICG-Lactosome, 0–350 mg/kg) was injected. Near-infrared fluorescence imaging was performed, and biodistribution of ICG-Lactosome was evaluated. Further, the produced amounts of anti-Lactosome IgM were determined by enzyme-linked immunosorbent assay (ELISA).

Results

ICG-Lactosome accumulated in the tumor region when the first Lactosome dose exceeded over 150 mg/kg. The amounts of anti-Lactosome IgM were inversely correlated with the first Lactosome doses. Even after establishment of the Lactosome ABC phenomenon with the first Lactosome dose as low as 5.0 mg/kg, the Lactosome ABC phenomenon can be evaded apparently by dosing ICG-Lactosome over 50 mg/kg regardless of anti-Lactosome IgM production.

Conclusions

There are two different mechanisms for evasion from the Lactosome ABC phenomenon before and after its establishment. In either mechanism, however, the Lactosome ABC phenomenon can be evaded by excessive administration of Lactosome.

General significance

Lactosome is a potential nanocarrier for drug and/or imaging agent delivery, which can be used for frequent administrations without significant pharmacokinetic alterations.     

Polyunsaturated fatty acids cause apoptosis in C. albicans and C. dubliniensis biofilms

Background

Polyunsaturated fatty acids (PUFAs) have antifungal properties, but the mode by which they induce their action is not always clear. The aim of the study was to investigate apoptosis as a mode of action of antifungal PUFAs (stearidonic acid, eicosapentaenoic acid and docosapentaenoic acid) which are inhibitory towards biofilm formation of C. albicans and C. dubliniensis.

Methods

Candida biofilms were grown in the absence or presence of 1 mM PUFAs (linoleic acid, stearidonic acid, eicosapentaenoic acid, docosapentaenoic acid) for 48 h at 37 °C. The effect of these PUFAs on the membrane fatty acid profile and unsaturation index, oxidative stress, mitochondrial transmembrane potential and apoptosis was evaluated.

Results

When biofilms of C. albicans and C. dubliniensis were exposed to certain PUFAs there was an increase in unsaturation index of the cellular membranes and accumulation of intracellular reactive oxygen species (ROS). This resulted in apoptosis, evidenced by reduced mitochondrial membrane potential and nuclear condensation and fragmentation. The most effective PUFA was stearidonic acid.

Conclusions

The resultant cell death of both C. albicans and C. dubliniensis is due to apoptosis.

General significance

Due to the increase in drug resistance, alternative antifungal drugs are needed. A group of natural antifungal compounds is PUFAs. However, understanding their mechanisms of action is important for further use and development of these compounds as antifungal drugs. This paper provides insight into a possible mode of action of antifungal PUFAs.     

The short and long term effects of docetaxel chemotherapy on rodent object recognition and spatial reference memory

Aims

Previous animal studies have examined the potential for cytostatic drugs to induce learning and memory deficits in laboratory animals but, to date, there is no pre-clinical evidence that taxanes have the potential to cause cognitive impairment. Therefore our aim was to explore the short- and long-term cognitive effects of different dosing schedules of the taxane docetaxel (DTX) on laboratory rodents.

Main methods

Healthy male hooded Wistar rats were treated with DTX (6 mg/kg, 10 mg/kg) or physiological saline (control), once a week for 3 weeks (Experiment 1) or once only (10 mg/kg; Experiment 2). Cognitive function was assessed using the novel object recognition (NOR) task and spatial water maze (WM) task 1 to 3 weeks after treatment and again 4 months after treatment.

Key findings

Shortly after DTX treatment, rats perform poorly on NOR regardless of treatment regimen. Treatment with a single injection of 10 mg/kg DTX does not appear to induce sustained deficits in object recognition or peripheral neuropathy.

Significance

Overall these findings show that treatment with the taxane DTX in the absence of cancer and other anti-cancer treatments causes cognitive impairment in healthy rodents.     

Histological and functional renal alterations caused by Bothrops alternatus snake venom: Expression and activity of Na/K-ATPase

Background

Acute renal failure is a serious complication of human envenoming by Bothrops snakes. The ion pump Na⁺/K⁺-ATPase has an important role in renal tubule function, where it modulates sodium reabsorption and homeostasis of the extracellular compartment. Here, we investigated the morphological and functional renal alterations and changes in Na⁺/K⁺-ATPase expression and activity in rats injected with Bothrops alternatus snake venom.

Methods

Male Wistar rats were injected with venom (0.8 mg/kg, i.v.) and renal function was assessed 6, 24, 48 and 72 h and 7 days post-venom. The rats were then killed and renal Na⁺/K⁺-ATPase activity was assayed based on phosphate release from ATP; gene and protein expressions were assessed by real time PCR and immunofluorescence microscopy, respectively.

Results

Venom caused lobulation of the capillary tufts, dilation of Bowman's capsular space, F-actin disruption in Bowman's capsule and renal tubule brush border, and deposition of collagen around glomeruli and proximal tubules that persisted seven days after envenoming. Enhanced sodium and potassium excretion, reduced proximal sodium reabsorption, and proteinuria were observed 6 h post-venom, followed by a transient decrease in the glomerular filtration rate. Gene and protein expressions of the Na⁺/K⁺-ATPase α₁ subunit were increased 6 h post-venom, whereas Na⁺/K⁺-ATPase activity increased 6 h and 24 h post-venom.

Conclusions

Bothrops alternatus venom caused marked morphological and functional renal alterations with enhanced Na⁺/K⁺-ATPase expression and activity in the early phase of renal damage.

General significance

Enhanced Na⁺/K⁺-ATPase activity in the early hours after envenoming may attenuate the renal dysfunction associated with venom-induced damage.     

Anti-inflammatory activity of methanol extract and n-hexane fraction mojabanchromanol b from Myagropsis myagroides

Aims

This study was carried out to verify the anti-inflammatory effect of methanol extract from Myagropsis myagroides (MMME) and its n-hexane fraction mojabanchromanol b.

Main methods

The murine macrophages Raw264.7 cells were used. The pro-inflammatory cytokines (IL-6, IL-1β, TNF-α) and the expression of iNOS, COX-2, and NF-κB p65 were examined by ELISA and immunoblotting. To investigate the inhibitory effect of MMME in an animal model of inflammation, an assay to determine croton oil-induced ear edema in mice was performed.

Key findings

NO levels decreased with increasing concentration of MMME, and were inhibited up to 50%. The secretion of IL-6, TNF-α, and IL-1β was suppressed in a dose-dependent manner, especially at 50 μg/mL, inhibition activities of cytokines were over 50%. MMME also suppressed the expression of COX-2, iNOS, and NF-κB p65, suggesting that MMME could affect the expression of inflammation related cytokines and proteins through the deregulation of NF-κB. Moreover, the formation of mouse ear edema was reduced at the highest dose tested compared to that in the control, and generated similar effects compared with prednisolone at 250 mg/kg in mice ear edema evaluation test. In addition, the results in photomicrograph of mice ear tissue and mast cells also showed the same effect. After purification of fractions of MMME, it indicated that n-hexane fraction mojabanchromanol b was the most active fraction showing the inhibitory effect of IL-6 and TNF-α.

Significance

These results suggested that MMME and mojabanchromanol b may have great effects on inflammatory factors and be potential anti-inflammatory therapeutic materials.     

Impaired cardiac mitochondrial function and contractile reserve following an acute exposure to environmental particulate matter

Background

It has been suggested that mitochondrial function plays a central role in cardiovascular diseases associated with particulate matter inhalation. The aim of this study was to evaluate this hypothesis, with focus on cardiac O₂ and energetic metabolism, and its impact over cardiac contractility.

Methods

Swiss mice were intranasally instilled with either residual oil fly ash (ROFA) (1.0 mg/kg body weight) or saline solution. After 1, 3 or 5 h of exposure, O₂ consumption was evaluated in heart tissue samples. Mitochondrial respiration, respiratory chain complexes activity, membrane potential and ATP content and production rate were assessed in isolated mitochondria. Cardiac contractile reserve was evaluated according to the Langendorff technique.

Results

Three hours after ROFA exposure, tissue O₂ consumption was significantly decreased by 35% (from 1180 ± 70 to 760 ± 60 ng-at O/min g tissue), as well as mitochondrial rest (state 4) and active (state 3) respiration, by 30 and 24%, respectively (control state 4: 88 ± 5 ng-at O/min mg protein; state 3: 240 ± 20 ng-at O/min mg protein). These findings were associated with decreased complex II activity, mitochondrial depolarization and deficient ATP production. Even though basal contractility was not modified (control: 75 ± 5 mm Hg), isolated perfused hearts failed to properly respond to isoproterenol in ROFA-exposed mice. Tissue O₂ consumption rates positively correlated with cardiac contractile state in controls (r² = 0.8271), but not in treated mice (r² = 0.1396).

General Significance

The present results show an impaired mitochondrial function associated with deficient cardiac contractility, which could represent an early cardiovascular alteration after the exposure to environmental particulate matter.     

Effect of rhynchophylline on conditioned place preference on expression of NR2B in methamphetamine-dependent mice

Objective

To study the effect of rhynchophylline on N-methyl d-aspartate receptor subtype 2B subunit in hippocampus of Methamphetamine-induced conditioned place preference (CPP) mice.

Methods

Place preference mice models were established by methamphetamine; the expression of NR2B was observed by immunohistochemistry technique and Western blot.

Results

Methamphetamine (4 mg/kg)-induced place preference mice model was successfully established; ketamine (15 mg/kg), rhynchophylline (40 mg/kg) and rhynchophylline (80 mg/kg) can eliminate place preference; Immunohistochemistry showed that the number of NR2B-positive neurons in hippocampus was increased in the methamphetamine model group, whereas less NR2B-positive neurons were found in the ketamine group, low and high dosage rhynchophylline group. Western blot showed that the expression of NR2B protein was significantly increased in the model group, whereas less expression was found in the ketamine group, low and high dosage rhynchophylline group.

Conclusions

NR2B plays an important role in the formation of methamphetamine-induced place preference in mice. Rhynchophylline reversed the expression of NR2B in the hippocampus demonstrates the potential effect of mediates methamphetamine induced rewarding effect.     

Interaction between gene A-positive Helicobacter pylori and human leukocyte antigen II alleles increase the risk of Graves disease in Chinese Han population: An association study

Objective

The current study explored the correlation of Helicobacter pylori and the polymorphisms of human leukocyte antigen II (HLA-II) alleles with Graves disease (GD).

Methods

A total of 216 patients with GD were recruited. 102 healthy volunteers constituted the control group. Levels of H. pylori immunoglobulin G (IgG) antibodies and H. pylori cytotoxin-associated gene A (CagA) IgG antibodies were detected using enzyme-linked immunosorbent assays. Molecular typing of the HLA-II alleles was conducted using polymerase chain reaction with sequence specific primers.

Results

H. pylori, particularly CagA-positive strains, HLA-DQA1*0201, and HLA-DQA1*0501 were associated with GD (P = 0.015, OR = 1.811; P = 0.000, OR = 3.085; P = 0.000, OR = 0.315; and P = 0.004, OR = 2.844, respectively). Patients with CagA-positive H. pylori and negative HLA-DQA1*0201 or positive HLA-DQA1*0501 were more likely exposed to GD compared with those with only one of these indices.

Conclusion

CagA-positive H. pylori, negative HLA-DQA1*0201, or positive HLA-DQA1*0501 may increase the risk of GD.     

Effect of fumagillin on adipocyte differentiation and adipogenesis

Background

Inhibition of angiogenesis may impair adipose tissue development.

Methods

The effect of fumagillin (a methionine aminopeptidase-2 inhibitor) on adipocyte differentiation and de novo adipogenesis was investigated in murine model systems.

Results

During in vitro differentiation of murine 3T3-F442A preadipocytes, administration of fumagillin (≥ 1 μM) resulted in reduced expression of methionine aminopeptidase-2, and in enhanced differentiation rate. In vivo, de novo development of adipose tissue following injection of preadipocytes in nude mice kept on high fat diet was somewhat, but not significantly (p = 0.06), reduced by administration of fumagillin (1 mg/kg/day during 4 weeks by oral gavage). This was not associated with effects on blood vessel size or density, whereas blood vessel density normalized to adipocyte density was enhanced upon fumagillin treatment. In vivo BrdU incorporation experiments did not reveal effects of fumagillin on cell proliferation in adipose tissues, and cellular apoptosis was also not affected.Treatment with fumagillin enhances in vitro differentiation of preadipocytes, but has only a minor effect on in vivo adipogenesis.

General Significance

These studies on in vitro and in vivo preadipcoyte differentiation thus do not support an anti-obesity effect of fumagillin as a result of effects on adipocyte differentiation.     

Selenium supplementation shows protective effects against patulin-induced brain damage in mice via increases in GSH-related enzyme activity and expression

Aims

This study was designed to investigate the protective effects of selenium supplementation on patulin-induced neurotoxicity.

Main methods

Mice were subjected to patulin for 8 weeks. Sodium selenite (Na₂SeO₃) and selenium–methionine (Se–Met) were supplemented with the diet, and we investigated the effects of selenium on patulin-induced neurotoxicity. The animals were randomly divided into 4 groups containing 6–8 mice each. The first group was used as a control, and only physiological saline (0.9%) was injected. The second group was treated with patulin (1 mg/kg) intraperitoneally. The third group was treated with patulin (1 mg/kg) along with a dietary supplementation of Na₂SeO₃ (0.2 mg Se/kg of diet). The fourth group was treated with patulin (1 mg/kg) plus Se–Met (0.2 mg Se/kg of diet).

Key findings

Patulin treatment increased oxidative damage in the brain, as evidenced by a decrease in non-protein thiol and total thiol groups, along with significant increases in GSSG, reactive oxygen species, thiobarbituric acid reactive substances and protein carbonyl levels. Moreover, the activities of glutathione peroxidase (GPx) and glutathione reductase were inhibited with patulin treatment. Selenium supplementation significantly ameliorated these biological parameter changes. In addition, selenium treatments significantly increased the mRNA levels of GPx-1, GPx-4 and thioredoxin reductase.

Significance

Our data show that selenium supplementation increases the activity and expression of glutathione-related enzymes and offers significant protection against brain damage induced by patulin.     

Insulin sensitization via partial agonism of PPARγ and glucose uptake through translocation and activation of GLUT4 in PI3K/p-Akt signaling pathway by embelin in type 2 diabetic rats

Background

The present study was aimed at isolating an antidiabetic molecule from a herbal source and assessing its mechanism of action.

Methods

Embelin, isolated from Embelia ribes Burm. (Myrsinaceae) fruit, was evaluated for its potential to regulate insulin resistance, alter β-cell dysfunction and modulate key markers involved in insulin sensitivity and glucose transport using high-fat diet (HFD) fed-streptozotocin (STZ) (40 mg/kg)-induced type 2 diabetic rats. Molecular-dockings were performed to investigate the binding modes of embelin into PPARγ, PI3K, p-Akt and GLUT4 active sites.

Results

Embelin (50 mg/kg b wt.) reduced body weight gain, blood glucose and plasma insulin in treated diabetic rats. It further modulated the altered lipid profiles and antioxidant enzymes with cytoprotective action on β-cell. Embelin significantly increased the PPARγ expression in epididymal adipose tissue compared to diabetic control group; it also inhibited adipogenic activity; it mildly activated PPARγ levels in the liver and skeletal muscle. It also regulated insulin mediated glucose uptake in epididymal adipose tissue through translocation and activation of GLUT4 in PI3K/p-Akt signaling cascade. Embelin bound to PPARγ; it disclosed stable binding affinities to the active sites of PI3K, p-Akt and GLUT4.

Conclusions

These findings show that embelin could improve adipose tissue insulin sensitivity without increasing weight gain, enhance glycemic control, protect β-cell from damage and maintain glucose homeostasis in adipose tissue.

General significance

Embelin can be used in the prevention and treatment of type 2 diabetes mellitus caused due to obesity.     

Combinational effects of farnesoid X receptor antagonist and statin on plasma lipid levels and low-density lipoprotein clearance in guinea pigs

Aims

We previously reported anti-dyslipidemic effects of a farnesoid X receptor antagonist in monkeys. In this study, we compared the cholesterol-lowering effects of single and combined administration of a farnesoid X receptor antagonist, compound-T8, and the 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor atorvastatin in a guinea pig model.

Main methods

Plasma levels of 7α-hydroxy-4-cholesten-3-one, a marker of hepatic cholesterol 7α-hydroxylase activity, were measured after a single administration of compound-T8. The effects of compound-T8 or atorvastatin on plasma cholesterol levels and low-density lipoprotein (LDL) clearance were investigated after 14 or 16 days of repeated dosing, respectively. Fractional catabolic rate of plasma LDL was estimated by intravenous injection of DiI-labeled human LDL. The cholesterol-lowering effects of combination therapy were investigated after 7 days of repeated treatment.

Key findings

Compound-T8 (10 and 30 mg/kg) increased plasma 7α-hydroxy-4-cholesten-3-one levels in a dose-dependent manner. Single administration of compound-T8 (30 mg/kg) and atorvastatin (30 mg/kg) reduced plasma non-high-density lipoprotein (non-HDL) cholesterol levels by 48% and 46%, respectively, and increased clearance of plasma DiI-labeled LDL by 29% and 35%, respectively. Compound-T8 (10 mg/kg) or atorvastatin (10 mg/kg) reduced non-HDL cholesterol levels by 19% and 25%, respectively, and combination therapy showed an additive effect and lowered cholesterol levels by 48%.

Significance

Similar to atorvastatin, compound-T8 reduced plasma non-HDL cholesterol levels accompanied with accelerated LDL clearance in guinea pigs. Combination therapy additively decreased plasma non-HDL cholesterol levels. Therefore, monotherapy with a farnesoid X receptor antagonist and combination therapy of a farnesoid X receptor antagonist with atorvastatin would be attractive dyslipidemia treatment options.     

Insight into genetic determinants of resting heart rate

Background

Recent studies suggested that resting heart rate (RHR) might be an independent predictor of cardiovascular mortality and morbidity. Nonetheless, the interrelation between RHR and cardiovascular diseases is not clear. In order to resolve this puzzle, the importance of genetic determinants of RHR has been recently suggested, but it needs to be further investigated.

Objective

The aim of this study was to estimate the contribution of common genetic variations on RHR using Genome Wide Association Study.

Methods

We performed a Genome Wide Association Study in an isolated population cohort of 1737 individuals, the Italian Network on Genetic Isolates — Friuli Venezia Giulia (INGI-FVG). Moreover, a haplotype analysis was performed. A regression tree analysis was run to highlight the effect of each haplotype combination on the phenotype.

Results

A significant level of association (p < 5 × 10^− 8) was detected for Single Nucleotide Polymorphisms (SNPs) in two genes expressed in the heart: MAML1 and CANX. Founding that the three different variants of the haplotype, which encompass both genes, yielded a phenotypic correlation. Indeed, a haplotype in homozygosity is significantly associated with the lower quartile of RHR (RHR ≤ 58 bpm). Moreover no significant association was found between cardiovascular risk factors and the different haplotype combinations.

Conclusion

Mastermind-like 1 and Calnexin were found to be associated with RHR. We demonstrated a relation between a haplotype and the lower quartile of RHR in our populations. Our findings highlight that genetic determinants of RHR may be implicated in determining cardiovascular diseases and could allow a better risk stratification.     

Inhibition by polyamines of the hammerhead ribozyme from a Chrysanthemum chlorotic mottle viroid

Background

Viroids are the smallest pathogens known to date. They infect plants and cause considerable economic losses. The members of the Avsunviroidae family are known for their capability to form hammerhead ribozymes (HHR) that catalyze self-cleavage during their rolling circle replication.

Methods

In vitro inhibition assays, based on the self-cleavage kinetics of the hammerhead ribozyme from a Chrysanthemum chlorotic mottle viroid (CChMVd-HHR) were performed in the presence of various putative inhibitors.

Results

Aminated compounds appear to be inhibitors of the self-cleavage activity of the CChMVd HHR. Surprisingly the spermine, a known activator of the autocatalytic activity of another hammerhead ribozyme in the presence or absence of divalent cations, is a potent inhibitor of the CChMVd-HHR with K_i of 17 ± 5 μM. Ruthenium hexamine and TMPyP4 are also efficient inhibitors with K_i of 32 ± 5 μM and IC₅₀ of 177 ± 5 nM, respectively.

Conclusions

This study shows that polyamines are inhibitors of the CChMVd-HHR self-cleavage activity, with an efficiency that increases with the number of their amino groups.

General significance

This fundamental investigation is of interest in understanding the catalytic activity of HHR as it is now known that HHR are present in the three domains of life including in the human genome. In addition these results emphasize again the remarkable plasticity and adaptability of ribozymes, a property which might have played a role in the early developments of life and must be also of significance nowadays for the multiple functions played by non-coding RNAs.     

Excitatory effects of bombesin receptors in urinary tract of normal and diabetic rats in vivo

Aims

Bombesin receptors (BB receptors) and bombesin related peptides are expressed in the lower urinary tract of rodents. Here we investigated whether in vivo activation of BB receptors can contract the urinary bladder and facilitate micturition in sham rats and in a diabetic rat model of voiding dysfunction.

Material and methods

In vivo cystometry experiments were performed in adult female Sprague–Dawley rats under urethane anesthesia. Diabetes was induced by streptozotocin (STZ; 65 mg/kg, i.p.) injection. Experiments were performed 9 and 20 weeks post STZ-treatment. Drugs included neuromedin B (NMB; BB1 receptor preferring agonist), and gastrin-releasing peptide (GRP; BB2 receptor preferring agonist).

Key findings

NMB and GRP (0.01–100 μg/kg in sham rats; 0.1–300 μg/kg in STZ-treated rats, i.v.) increased micturition frequency, bladder contraction amplitude and area under the curve dose dependently in both sham and STZ-treated rats. In addition, NMB (3, 10 μg/kg i.v.) triggered voiding in > 80% of STZ-treated rats when the bladder was filled to a sub-threshold voiding volume. NMB and GRP increased mean arterial pressure and heart rate at the highest doses, 100 and 300 μg/kg.

Significance

Activation of bombesin receptors facilitated neurogenic bladder contractions in vivo. Single applications of agonists enhanced or triggered voiding in sham rats as well as in the STZ-treated rat model of diabetic voiding dysfunction. These results suggest that BB receptors may be targeted for drug development for conditions associated with poor detrusor contraction such as an underactive bladder condition.     

Association between interleukin 4 gene intron 3 VNTR polymorphism and recurrent aphthous stomatitis in a cohort of Turkish patients

Objective

Recurrent aphthous stomatitis (RAS) is one of the most common oral mucosal diseases, with a multifactorial etiopathogenesis, an interaction between predisposing factors and/or systemic conditions and immunological components in genetically predisposed subjects. Although there is no clear genetic mode of inheritance, there is evidence that inheritance of specific gene polymorphisms may predispose individuals to RAS. The purpose of the present study was to investigate a possible association between the functional interleukin 4 (IL4) VNTR genetic polymorphism and RAS in a sample of Turkish patients.

Methods

The study included 145 unrelated patients with a clinical diagnosis of RAS and 150 unrelated healthy controls. Genomic DNA was isolated and IL4 gene 70 bp VNTR polymorphism determined by using polymerase chain reaction (PCR) with specific primers.

Results

The distribution of genotype and allele frequencies of IL4 gene intron 3 VNTR polymorphism was statistically different between RAS patients and control group (p < 0.0001 and p < 0.0001, respectively) P2P2 genotype and P2 allele were also found to be protective with a lower risk for susceptibility to RAS (p < 0.0001).

Conclusion

The results of this study suggest that intron 3 VNTR polymorphism in the IL4 gene is associated with RAS susceptibility in Turkish population.