Procyanidins alleviates morphine tolerance by inhibiting activation of NLRP3 inflammasome in microglia

Background

The development of antinociceptive tolerance following repetitive administration of opioid analgesics significantly hinders their clinical use. Evidence has accumulated indicating that microglia within the spinal cord plays a critical role in morphine tolerance. The inhibitor of microglia is effective to attenuate the tolerance; however, the mechanism is not fully understood. Our present study investigated the effects and possible mechanism of a natural product procyanidins in improving morphine tolerance via its specific inhibition on NOD-like receptor protein3 (NLRP3) inflammasome in microglia.

Methods

CD-1 mice were used for tail-flick test to evaluate the degree of pain. The microglial cell line BV-2 was used to investigate the effects and the mechanism of procyanidins. Reactive oxygen species (ROS) produced from BV-2 cells was evaluated by flow cytometry. Cell signaling was measured by western blot assay and immunofluorescence assay.

Results

Co-administration of procyanidins with morphine potentiated its antinociception effect and attenuated the development of acute and chronic morphine tolerance. Procyanidins also inhibited morphine-induced increase of interleukin-1β and activation of NOD-like receptor protein3 (NLRP3) inflammasome. Furthermore, procyanidins decreased the phosphorylation of p38 mitogen-activated protein kinase, inhibited the translocation of nuclear factor-κB (NF-κB), and suppressed the level of reactive oxygen species in microglia.

Conclusions

Procyanidins suppresses morphine-induced activation of NLRP3 inflammasome and inflammatory responses in microglia, and thus resulting in significant attenuation of morphine antinociceptive tolerance.

Electronic supplementary material

The online version of this article (doi:10.1186/s12974-016-0520-z) contains supplementary material, which is available to authorized users.

Serology, virulence, antimicrobial susceptibility and molecular characteristics of clinical Vibrio parahaemolyticus strains circulating in southeastern China from 2009 to 2013

Vibrio parahaemolyticus is a leading cause of food-borne diarrhoea in coastal countries. Although V. parahaemolyticus cases have been reported since 1950, they have been poorly documented. From July 2009 to June 2013, we collected 6951 faecal specimens for pathogen detection; V. parahaemolyticus strains were isolated from 563 specimens (8.1%). We then analysed the characteristics of the 501 V. parahaemolyticus strains that were isolated as the sole pathogen. Twenty-one serotypes were identified among these strains; O3:K6 was the most common serotype (65.1%), followed by O4:K8, O4:K68 and O1:K36. One strain of the O4:K18 serotype was isolated from clinical patients for the first time. Pandemic O3:K6 clones were predominant and accounted for 69.1% of all of the pandemic strains. This is the first report of one strain expressing the O3:K8 serotype with a pandemic genotype. The presence of the haemolysin gene tdh (93.0%) was the key characteristic of the virulent strains; however, a few strains carried the trh gene. We also confirmed the presence of the type III secretion system 2 (T3SS2) genes in all of the pathogenic strains. Subsequent multilocus sequence typing split the isolates into 16 sequence types (STs), with ST3 and ST88 as the most prevalent in southeastern China. Most isolates were sensitive to common antimicrobial agents, apart from ampicillin. However, the resistance rate to ampicillin has apparently increased in this area. In conclusion, our results indicate that pandemic O3:K6 V. parahaemolyticus isolates are predominant in southeastern China, and additional surveillance should be conducted to facilitate control of the transmission of this pathogen.

Association of vitamin D-binding protein variants with chronic obstructive pulmonary disease: a meta-analysis

Gene polymorphism of vitamin D-binding protein (VDBP) correlates with chronic obstructive pulmonary disease (COPD), but the results remain inconclusive. We aimed to explore the association between VDBP gene polymorphism and COPD. We searched MEDLINE, Embase, Web of Science, and China National Knowledge Infrastructure for publications addressing the association between VDBP gene polymorphism and COPD. After qualitative evaluation, randomized controlled trials were pooled using either a fixed- or a random-effect model depending upon the degree of heterogeneity. Eleven studies with 3144 subjects were included. The genotype group-specific component (GC)*1F-1F was significantly associated with COPD in Asians [odds ratio (OR) = 1.73, 95% confidence interval (CI) = 1.07-2.81, P = 0.03], but not in Caucasians (OR = 1.44, 95%CI = 0.57-3.66, P = 0.45). A protective effect of GC*1F-1S was observed in Asians (OR = 0.70, 95%CI = 0.55-0.89, P = 0.003) but not in Caucasians (OR = 0.93, 95%CI = 0.69-1.24, P = 0.61). There was no association of GC*1S-1S, GC*2-1S and GC*1F-2 with COPD. As for alleles, GC*1F was a risk factor, whereas GC*1S was protective against COPD in Asians; GC*2 was not protective. The genotype GC*1F-1F or allele GC*1F was associated with increased susceptibility to COPD in Asians. No protective effect of genotype GC*2-2 against COPD was found. The protective effects of GC*1F-1S and GC*1S were observed in Asians but not in Caucasians. The VDBP gene polymorphism could be a potential marker for screening of COPD.

Intercellular adhesion molecule-1 expression in activated eosinophils is associated with mucosal remodeling in nasal polyps

Nasal polyposis (NP) is characterized by chronic mucosal inflammation with infiltrating eosinophils. Eosinophil-mediated tissue remodeling may be involved in NP pathogenesis; therefore, improved understanding of tissue remodeling may result the identification of novel pathways and therapeutic strategies. The present study aimed to investigate the pathological changes occurring during tissue remodeling in NP, in order to assess the role of intercellular adhesion molecule-1 (ICAM-1) in localized tissue remodeling and the potential association between ICAM-1 expression and markers of eosinophil activation. A total of 28 eligible patients and 10 healthy controls participated in the current study. Nasal mucosal tissues of these subjects were retrospectively evaluated for mucosal remodeling using histopathological staining. ICAM-1 and eosinophil cationic protein (ECP) expression levels were determined by immunohistochemical analysis. Compared with the healthy controls, all the specimens from NP patients presented substantial epithelial damage, skewed cellular distribution with a reduced density of goblet cells, an increased density of subepithelial gland and increased subepithelial collagen deposition. In addition, the NP specimens exhibited significantly higher eosinophil infiltration and ICAM-1 expression compared with the controls. Positive correlations were observed between ICAM-1 and ECP expression levels (P=0.010), as well as between extracellular collagen deposition and ICAM-1 (P=0.010) and ECP (P=0.012) expression levels in the NP specimens, but not in the control specimens. Morphological evidence demonstrated eosinophil-mediated tissue remodeling in NP tissues. ICAM-1 expression in activated eosinophils was associated with NP remodeling, indicating the possibility that ICAM-1 may regulate NP remodeling.

Analysis of Predisposing Factor for Pharyngocutaneous Fistula in Laryngeal Carcinoma Patients

Objectives:

Pharyngeal fistula is the most common and troublesome postoperative complication after surgery of larynx, lower pharynx, and cervical esophagus carcinoma. This study aims to identify (1) the potential predisposing factors of pharyngeal fistula in laryngeal carcinoma patients after laryngectomy and (2) how nutritional support during treatment would contribute to improve prognosis.

Methods:

Retrospective review of 156 consecutive cases of laryngeal carcinoma patients who underwent laryngectomy from 2011 to 2013 at China-Japan Union Hospital, Jilin University. Nutritional support and other potential predisposing factors were analyzed between patients with and without pharyngeal fistula.

Results:

Among the 156 cases studied, 6.4% of patients demonstrated postoperative pharyngeal fistula. Many predisposing factors showed statistical significance ( P < .05 or P < .001) in this study, such as smoking history ( P < .05), neck dissection ( P < .001), duration of operation ( P < .05), postoperative serum albumin/total protein level ( P < .001and P < .001, respectively), and body weight change after surgery ( P < .05). Other factors, such as age, sex, hemoglobin level, tumor stage, surgical option, and hypertension, did not show any statistical significance. Furthermore, patients with malnutrition have much higher risk of developing pharyngeal fistula.

Conclusions:

The occurrence of pharyngeal fistula in laryngeal carcinoma patients is highly associated with the duration of smoking, neck dissection, duration of operation, postoperative serum albumin/total protein level, and body weight change. By optimizing the patients’ general preoperation conditions and synchronous nutritional support, it would largely enhance the therapeutic response, reduce incidence, and improve prognosis.

Involvement of NLRP3 inflammasome in rituximab-induced interstitial lung disease: a case report

WHAT IS KNOWN AND OBJECTIVE

Rituximab is a chimeric anti-CD20 IgG1 monoclonal antibody for the treatment of various forms of lymphoma and haematological autoimmune diseases. Interstitial lung disease is a rare but lethal pulmonary toxicity of rituximab. Nod-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasome is a molecular platform activated upon signs of cellular 'danger' to trigger the maturation of pro-inflammatory cytokines. We report the first case of rituximab-induced interstitial lung disease (R-ILD) with NLRP3 inflammasome activation in the lung.

CASE SUMMARY

A 30-year-old male patient diagnosed with idiopathic thrombocytopenic purpura (ITP) was treated with four cycles of rituximab in one month. Three weeks after last rituximab administration, he developed progressive dyspnoea associated with respiratory failure, which was diagnosed as R-ILD. The patient showed a good response to steroid treatment, and lung biopsy was performed 5 days after the treatment. Immunohistopathological studies of lung specimens showed high expressions of inflammasome components NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) and caspase-1 in lung interstitium with a heavy infiltration of CD19-positive cells. The levels of inflammasome-related cytokines IL-1β and IL-18 in the serum were declined during the therapy.

WHAT IS NEW AND CONCLUSIONS

This is the first report confirmed the role of NLRP3 inflammasome in pulmonary toxicity of rituximab. Inhibited activation of NLRP3 inflammasome in lung by steroid treatment could reverse R-ILD and block subsequent lung fibrosis. This result could open a new sight into the pathogenesis and provide a new target for the treatment of R-ILD.

The effectiveness of noninvasive biomarkers to predict hepatitis B-related significant fibrosis and cirrhosis: a systematic review and meta-analysis of diagnostic test accuracy

Noninvasive biomarkers have been developed to predict hepatitis B virus (HBV)-related fibrosis owing to the significant limitations of liver biopsy. Those biomarkers were initially derived from evaluation of hepatitis C virus (HCV)-related fibrosis, and their accuracy among HBV-infected patients was under constant debate. A systematic review was conducted on records in PubMed, EMBASE and the Cochrane Library electronic databases, up until April 1st, 2013, in order to systematically assess the effectiveness and accuracy of these biomarkers for predicting HBV-related fibrosis. The questionnaire for quality assessment of diagnostic accuracy studies (QUADAS) was used. Out of 115 articles evaluated for eligibility, 79 studies satisfied the pre-determined inclusion criteria for meta-analysis. Eventually, our final data set for the meta-analysis contained 30 studies. The areas under the SROC curve for APRI, FIB-4, and FibroTest of significant fibrosis were 0.77, 0.75, and 0.84, respectively. For cirrhosis, the areas under the SROC curve for APRI, FIB-4 and FibroTest were 0.75, 0.87, and 0.90, respectively. The heterogeneity of FIB-4 and FibroTest were not statistically significant. The heterogeneity of APRI for detecting significant fibrosis was affected by median age (P = 0.0211), and for cirrhosis was affected by etiology (P = 0.0159). Based on the analysis we claim that FibroTest has excellent diagnostic accuracy for identification of HBV-related significant fibrosis and cirrhosis. FIB-4 has modest benefits and may be suitable for wider scope implementation.

Serum paraoxonase, arylesterase activities and oxidative status in patients with insomnia

AIM

The aim of this study was to investigate serum paraoxonase (PON) activity, arylesterase (ARE) activity, total antioxidant status (TAS), total oxidant status (TOS) and oxidative stress index (OSI) levels in patients with insomnia and to determine whether there was a relationship between oxidative stress and insomnia.

PATIENTS AND METHODS

A total of 29 insomniacs and 25 healthy controls were recruited in this study. Serum PON and ARE activities, TAS and TOS level were determined, and OSI were calculated.

RESULTS

Patients with insomnia had lower PON and ARE activities as compared to healthy controls (PON: 82.0±30.0 U/L vs. 193.5±58.4 U/L, p < 0.001; ARE: 143.0±26.7 U/L vs. 175.0±27.1 U/L, p < 0.001; respectively). Serum TAS was lower, while TOS and OSI were higher in the insomnia group than in the control group (TAS: 1.13±0.29 mmol Trolox equivalent/L vs. 1.70±0.35 mmol Trolox equivalent /L, p < 0.001; TOS: 18.68±5.03 µmol H2O2 equivalent/L vs. 10.92±2.21 µmol H2O2 equivalent/L, p < 0.001; OSI: 1.76±0.74 vs. 0.68±0.23, p < 0.001; respectively).

CONCLUSIONS

Patients with insomnia have increased systemic oxidative stress and reduced levels of serum antioxidant enzymes. Oxidative stress appears to be an underlying condition associated with insomnia.

TMPRSS4 as a poor prognostic factor for triple-negative breast cancer

Triple-negative breast cancer (TNBC) is characterized by the lack of immunohistochemical staining for estrogen receptors (ER), progesterone receptors (PR), and lack of overexpression or amplification of human epidermal growth factor receptor 2 (HER2). Our aim was to investigate the expression of transmembrane protease, serine 4 (TMPRSS4) in TNBC patients and its possible relationship to the outcome of the disease. A total of 72 TNBC patients and 109 non-TNBC patients who were diagnosed between 2003 and 2008 were enrolled in this study. Immunohistochemistry was used to compare the expression pattern of TMPRSS4 in TNBC and non-TNBC groups, and the prognostic significance was assessed by Kaplan-Meier analysis and Cox proportional hazards regression in TNBC patients. The rate of high expression of TMPRSS4 was significantly higher in TNBC group than that in non-TNBC group. High expression of TMPRSS4 was significantly correlated with lymph node metastasis, histological grade, and tumor size. TNBC patients with high TMPRSS4 expression showed the poorer overall survival (OS) and disease-free survival (DFS) than those patients with low TMPRSS4 expression. In multivariate analysis, only lymph node metastasis and TMPRSS4 expression were the independent prognostic factors for OS and DFS in TNBC. Our study provides evidence that TMPRSS4 expression is associated with lymph node metastasis, tumor size, and histological grade in TNBC patients, and also is an independent prognostic factor for TNBC.

Polymorphism of ZBTB17 gene is associated with idiopathic dilated cardiomyopathy: a case control study in a Han Chinese population

BACKGROUND

Dilated cardiomyopathy (DCM) has been extensively investigated for many years, but its pathogenesis remains uncertain. The ACTC1 gene was the first sarcomeric gene whose mutation was shown to cause DCM; recent studies have indicated that the HSPB7 and ZBTB17 genes are also associated with DCM. To assess the potential role of these three genes in DCM, we examined 11 single nucleotide polymorphisms (SNPs) in the ZBTB17, HSPB7 and ACTC1 genes: namely, rs10927875 in ZBTB17; rs1739843, rs7523558, and rs6660685 in HSPB7; rs533021, rs589759, rs1370154, rs2070664, rs3759834, rs525720 and rs670957 in ACTC1.

METHODS

A total of 97 DCM patients and 189 controls were included in the study. All SNPs were genotyped by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS).

RESULTS

The genotype of SNP rs10927875 in ZBTB17 (OR=5.19, 95% CI =1.00 to 27.03, P=0.05) was associated with DCM in a Han Chinese population. There was no difference in genotype or allele frequencies in ACTC1 or HSPB7 between DCM patients and control subjects.

CONCLUSION

The ZBTB17 polymorphism rs10927875 appears to play a role in the susceptibility of the Han Chinese population to DCM.

Serotypes, genotypes and antimicrobial resistance patterns of human diarrhoeagenic Escherichia coli isolates circulating in southeastern China

Diarrhoeagenic Escherichia coli (DEC) infection is a major health problem in developing countries. The prevalence and characteristics of DEC have not been thoroughly investigated in China. Consecutive faecal specimens from outpatients with acute diarrhoea in nine sentinel hospitals in southeastern China were collected from July 2009 to June 2011. Bacterial and viral pathogens were detected by culture and RT-PCR, respectively. DEC isolates were further classified into five pathotypes using multiplex PCR. The O/H serotypes, sequence types (STs) and antimicrobial susceptibility profiles of the DEC isolates were determined. A total of 2466 faecal specimens were collected, from which 347 (14.1%) DEC isolates were isolated. DEC was the dominant bacterial pathogen detected. The DEC isolates included 217 EAEC, 62 ETEC, 52 EPEC, 14 STEC, one EIEC and one EAEC/ETEC. O45 (6.6%) was the predominant serotype. Genotypic analysis revealed that the major genotype was ST complex 10 (87, 25.6%). Isolates belonging to the serogroups or genotypes of O6, O25, O159, ST48, ST218, ST94 and ST1491 were highly susceptible to the majority of antimicrobials. In contrast, isolates belonging to O45, O15, O1, O169, ST38, ST226, ST69, ST31, ST93, ST394 and ST648 were highly resistant to the majority of antimicrobials. DEC accounted for the majority of bacterial pathogens causing acute diarrhoea in southeastern China, and it is therefore necessary to test for all DEC, not only the EHEC O157:H7. Some serogroups or genotypes of DEC were highly resistant to the majority of antimicrobials. DEC surveillance should be emphasized.

Dopamine D3 receptors regulate reconsolidation of cocaine memory

Memories of learned associations between the rewarding properties of drugs of abuse and environmental cues contribute to craving and relapse in humans. Disruption of reconsolidation dampens or even erases previous memories. Dopamine (DA) mediates the acquisition of reward memory and drugs of abuse can pathologically change related neuronal circuits in the mesolimbic DA system. Previous studies showed that DA D3 receptors are involved in cocaine-conditioned place preference (CPP) and reinstatement of cocaine-seeking behavior. However, the role of D3 receptors in reconsolidation of cocaine-induced reward memory remains unclear. In the present study, we combined genetic and pharmacological approaches to investigate the role of D3 receptors in reconsolidation of cocaine-induced CPP. We found that the mutation of the D3 receptor gene weakened reconsolidation of cocaine-induced CPP in mice triggered by a 3-min (min) retrieval. Furthermore, treatment of a selective D3 receptor antagonist PG01037 immediately following the 3-min retrieval disrupted reconsolidation of cocaine-induced CPP in wild-type mice and such disruption remained at least 1 week after the 3-min retrieval. These results suggest that D3 receptors play a key role in reconsolidation of cocaine-induced CPP in mice, and that pharmacological blockade of these receptors may be therapeutic for the treatment of cocaine craving and relapse in clinical settings.

Downregulation of Mcl-1 through inhibition of translation contributes to benzyl isothiocyanate-induced cell cycle arrest and apoptosis in human leukemia cells

Benzyl isothiocyanate (BITC) is one of the compounds of ITCs' family that has attracted a great deal of interest because of its ability to exhibit anticancer activity. In this study, we investigated the effects of BITC on cell cycle arrest and apoptosis in human leukemia cell lines, primary leukemia cells, and nude mice Jurkat xenograft. Exposure of Jurkat cells to BITC resulted in dose- and time-dependent increase in apoptosis, caspase activation, cytochrome c release, nuclear apoptosis-inducing factor (AIF) accumulation, Bcl2-associated X protein (Bax) translocation, and myeloid cell leukemia-1 (Mcl-1) downregulation. Treatment with these cells also resulted in cell cycle arrest at the G2/M phase. The G2/M-arrested cells are more sensitive to undergoing Mcl-1 downregulation and apoptosis mediated by BITC. BITC downregulates Mcl-1 expression through inhibition of translation, rather than through a transcriptional, post-translational, or caspase-dependent mechanism. Dephosphorylation of eukaryotic initiation factor 4G could contribute to the inhibition of Mcl-1 translation mediated by BITC. Furthermore, ectopic expression of Mcl-1 substantially attenuates BITC-mediated lethality in these cells, whereas knockdown of Mcl-1 through small interfering RNA significantly enhances BITC-mediated lethality. Finally, administration of BITC markedly inhibited tumor growth and induced apoptosis in Jurkat xenograft model in association with the downregulation of Mcl-1. Taken together, these findings represent a novel mechanism by which agents targeting Mcl-1 potentiate BITC lethality in transformed and primary human leukemia cells and inhibitory activity of tumor growth of Jurkat xenograft model.

rG17PE38, a novel immunotoxin target to gastric cancer with overexpressed CCK-2R

BACKGROUND

Gastrin/cholecystokinin subtype 2 receptor (CCK2R) is overexpressed in several types of tumors. Gastrin-17 (G17) peptide has a high affinity with CCK2R. These characters suggest that G17 may be useful for target cancer therapy.

PURPOSE

Construct a new immunotoxin (IT) targeting of CCK2R overexpressed gastric cancer.

METHODS

Two ITs were generated using forward and reverse G17 peptides fused with PE38. To get a high yield, codon optimized gene and optimized fermentation parameters were used in large-scale protein expression. An immunoaffinity technique was introduced into pseudomonas exotoxin (PE)-derived IT purification procedure. G17 competition, GST pull-down and indirect immunoflourescence assays were carried out to confirm the interaction between rG17 and CCK2R. Then, several cytotoxic assays were carried out on 18 cell lines, and an in vivo antitumor activity experiment was tested in nude mice.

RESULTS

The rG17PE38 showed specific cytotoxicity on three gastric cancer cells, while G17PE38 did not. After optimization, the expression level reached about 40% in medium deprived of NaCl. Next, 15-27.5 mg of pure rG17PE38 per 1 L of cultures was obtained. Results of G17 competition, GST pull-down and indirect immunoflourescence assays demonstrated that rG17 have a specific interact with CCK2R. Purified rG17PE38 showed high cytotoxicity on gastric cancer cell lines with the IC50 value of 0.6-4 ng·mL(-1). Treatment of nude mice inoculated with BGC-823 tumor xenografts with rG17PE38 efficiently inhibited tumor size.

CONCLUSIONS AND DISCUSSION

The present study demonstrates that reversed G17 could be used as target moiety of PE-derived IT and the rG17PE38 could be developed as a new immunotherapy agent. Codon optimized gene could increase the rG17PE38 expression level in E. coli and furthermore NaCl inhibits the rG17PE38 expression in large scale. Meanwhile, our present study inducts an immunoaffinity method in the IT purification procedure, which could purify the PE-derived ITs in native form.

The β1-adrenoreceptor gene Arg389Gly and Ser49Gly polymorphisms and hypertension: a meta-analysis

The gene encoding β1-adrenoreceptor is regarded as a hypertension-susceptibility candidate gene. The association of β1-adrenoreceptor gene Arg389Gly and Ser49Gly polymorphisms with hypertension has been exhaustively investigated; however, the studies have yielded inconsistent results. We sought to shed some light on this inconsistency by performing a systemic meta-analysis. Data were extracted from 17 articles (cases/controls: 7,586/8,441) for Arg389Gly, and eight articles (3,582/2,998) for Ser49Gly. The random-effects model was applied irrespective of between-study heterogeneity. Overall results indicated significance for Ser49Gly under both allelic (odds ratio = 1.13; 95 % confidence interval [95 % CI] 1.03-1.26; P = 0.011) and dominant (1.19; 1.04-1.28; 0.011) models, without evidence of heterogeneity (I (2) = 0.0 %). Grouping studies by ethnicity observed marginally significant association for Arg389Gly (0.82; 0.66-1.0; 0.049) and Ser49Gly (1.3; 1.0-1.68; 0.048) polymorphisms in Caucasians under allelic model. Association was strikingly potentiated for both polymorphisms after restricting analyses to studies published in English journals. When only large studies (≥500 subjects) were considered, 389Gly allele decreased the odds of developing hypertension by 16 % (0.84; 0.74-0.95; 0.007). There was no observable publication bias for both polymorphisms. Taken together, our results provide clarification to the logical candidacy of β1-adrenoreceptor gene in the development of hypertension.