Anemoside B4, a new pyruvate carboxylase inhibitor, alleviates colitis by reprogramming macrophage function.

OBJECTIVES: Colitis is a global disease usually accompanied by intestinal epithelial damage and intestinal inflammation, and an increasing number of studies have found natural products to be highly effective in treating colitis. Anemoside B4 (AB4), an abundant saponin isolated from Pulsatilla chinensis (Bunge), which was found to have strong anti-inflammatory activity. However, the exact molecular mechanisms and direct targets of AB4 in the treatment of colitis remain to be discovered. METHODS: The anti-inflammatory activities of AB4 were verified in LPS-induced cell models and 2, 4, 6-trinitrobenzene sulfonic (TNBS) or dextran sulfate sodium (DSS)-induced colitis mice and rat models. The molecular target of AB4 was identified by affinity chromatography analysis using chemical probes derived from AB4. Experiments including proteomics, molecular docking, biotin pull-down, surface plasmon resonance (SPR), and cellular thermal shift assay (CETSA) were used to confirm the binding of AB4 to its molecular target. Overexpression of pyruvate carboxylase (PC) and PC agonist were used to study the effects of PC on the anti-inflammatory and metabolic regulation of AB4 in vitro and in vivo. RESULTS: AB4 not only significantly inhibited LPS-induced NF-κB activation and increased ROS levels in THP-1 cells, but also suppressed TNBS/DSS-induced colonic inflammation in mice and rats. The molecular target of AB4 was identified as PC, a key enzyme related to fatty acid, amino acid and tricarboxylic acid (TCA) cycle. We next demonstrated that AB4 specifically bound to the His879 site of PC and altered the protein's spatial conformation, thereby affecting the enzymatic activity of PC. LPS activated NF-κB pathway and increased PC activity, which caused metabolic reprogramming, while AB4 reversed this phenomenon by inhibiting the PC activity. In vivo studies showed that diisopropylamine dichloroacetate (DADA), a PC agonist, eliminated the therapeutic effects of AB4 by changing the metabolic rearrangement of intestinal tissues in colitis mice. CONCLUSION: We identified PC as a direct cellular target of AB4 in the modulation of inflammation, especially colitis. Moreover, PC/pyruvate metabolism/NF-κB is crucial for LPS-driven inflammation and oxidative stress. These findings shed more light on the possibilities of PC as a potential new target for treating colitis.

Phenotype, molecular characterisation and risk factors for postoperative meningitis caused by ESBL-producing-Enterobacteriaceae: a six years multi-Centre comparative cohort study.

BACKGROUND: To determine the phenotype, molecular characterisation and risk factors of postoperative meningitis induced by Extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae (EPE) in China. METHODS: We performed a multi-centre comparative cohort study of postoperative meningitis patients infected with Enterobacteriaceae in 4 neurosurgical centres in China from January 2014 to December 2019. Phenotype and molecular characteristics of the isolates were reviewed and tested, and independent risk factors of the EPE meningitis were evaluated by binary logistic regression. RESULTS: In total, 220 Enterobacteriaceae include 78 EPE were available in this study. 85.6% (67/78) ESBL-related genes were tested, and blaSHV (14.9%) and blaSHV + blaTEM + blaCTX-M-9 (20.9%) were found to be the most frequent mono and combined ESBL-related genes harboured by Enterobacteriaceae. On binary logistic analysis, craniotomy (OR. 2.583, 95% C.I. 1.274-5.235, P = 0.008) and malignancy (OR. 2.406, 95% C.I. 1.299-4.456, P = 0.005) were the associated independent risk factors to meningitis induced by EPE. CONCLUSIONS: To the best of our knowledge, this is the largest series focusing on risk factors of EPE meningitis which has been conducted in China. Craniotomy and malignancy were independent risk factors for EPE meningitis. The risk factors identified may be further utilized in clinical practice and research to avoid and reduce the mortality in future.

Epidemiology and risk factors of neurosurgical bacterial meningitis/encephalitis induced by carbapenem resistant Enterobacteriaceae.

OBJECTIVES: This is a retrospective observational study conducted in one of the largest clinical center of neurosurgery in China. Our aim was to determine the epidemiological characteristics of carbapenem-resistant Enterobacteriaceae (CRE) related meningitis/encephalitis and to elucidate the risk factors for CRE neurosurgical infections. PATIENTS AND METHODS: We performed a retrospective study between January 2012 and December 2017 of patients who underwent neurosurgery. The medical records of each patient were reviewed, and 20 clinical variables on risk factors were extracted and evaluated by Multivariate logistic analysis for CRE-meningitis/encephalitis. RESULTS: In 2012-2017, the positive rate of neurosurgical meningitis/encephalitis was 7.9% (2947/29605), Enterobacteriaceae accounted for 6.3% (185/2947) of all bacterial infections. Totally, 133 Enterobacteriaceae include 26 CRE isolates were available in this study. Of them, Univariate analysis showed that the risk factors of CRE meningitis were ventilator, bacteremia, Intensive Care Unit (ICU) admission, hospital acquired pneumonia and mortality attribute to infection. Multivariate logistic analysis showed that hospital acquired pneumonia and mortality attribute to infection were independent risk factors for CRE meningitis. CONCLUSION: CRE is one of the most serious drug-resistant bacteria published by World Health Organization (WHO) in 2016, and meningitis/encephalitis caused by CRE is an important sign of the failure of the neurosurgery, which demands the physician's immediate attention.

Intermittent high glucose promotes expression of proinflammatory cytokines in monocytes.

OBJECTIVE AND DESIGN: The aim of this study was to examine expression of proinflammatory cytokines in monocytes under fluctuating glucose conditions. MATERIAL AND TREATMENT: Monocytic cells (THP-1) were divided into four groups and cultured in the presence of 5 or 15 mmol/L glucose or in fluctuating conditions (12 h exposure to 15 mmol/L glucose or mannitol medium followed by 12 h exposure to 5 mmol/L glucose or mannitol medium) respectively. METHODS: Levels of interleukin (IL)-6 and tumor necrosis factor (TNF)-α in the supernatants and surface expression of CD11b in monocytes were measured after 72 h culture. Paired Student's t tests were used to compare two groups and ANOVA for multiple comparisons. RESULTS: Activation of monocytes was most pronounced in the fluctuating glucose conditions, as measured by concentrations of IL-6 and TNF-α in cultured supernatants and surface expression of CD11b in monocytes (P < 0.05). Fluctuating mannitol also induced a proinflammatory profile, but to a lesser extent than fluctuating glucose. CONCLUSIONS: The results indicated that exposure to fluctuating glucose concentrations enhanced activation of monocytes compared with stable elevation of glucose concentrations. The effects were partly attributable to the inherent osmotic changes.

Serum ceramide concentrations are associated with depression in patients after ischemic stroke-A two-center case-controlled study.

BACKGROUND AND AIMS: The present study aims to correlate the severity of post-stroke depression (PSD) and serum ceramide concentration. MATERIALS AND METHODS: In this two-center case-control study, we prospectively collected clinical and demographical information from age and gender-matched 51 PSD patients, 56 non-post-stroke depression (Non-PSD) patients, and 39 patients with major depression (MD) to perform the suitable biochemical analysis to bring a correlation in causing depression in patients soon after the stroke. The ROC curve method was used to evaluate ceramide's diagnostic efficacy in all three groups of patients. A follow-up analysis was also conducted based on PSD severity to associate serum ceramide levels and neuropsychiatric symptoms. The severity of the patient's depressive symptoms was assessed by using the self-rating depression scale (SDS). RESULTS: In comparison between PSD and MD patients, three serum ceramide species were found to be significantly different. Compared with Non-PSD patients, PSD patients had significantly higher levels of all the four serum ceramides, and increasing levels ofC16:0, C18:0(VS MD) and C16: 0(VS Non-PSD) serve as a diagnostic tool and an independent risk factor in all three categories of patients. Moreover, the follow-up analysis results showed that, as the treatment progressed, the differences in the 3 serum ceramide species were statistically significant. CONCLUSION: There was a stage-specific association between serum ceramides and PSD, and the potential pathophysiological mechanism has to be investigated in future research.

Abnormal expression of dopamine and serotonin transporters associated with the pathophysiologic mechanism of Tourette syndrome.

BACKGROUND: Tourette syndrome (TS) is a neurobehavioral and neuropsychiatric disorder and its pathophysiology is not well understood. However, recent studies provide evidence implicating metabolic abnormalities of dopamine (DA) and serotonin (5-HT) of the basal ganglia both in TS patients and TS animal models. It is also well known that dopamine and serotonin transporters (DAT and SERT) are monoamine neurotransmitter transporters, which participate in the metabolism of DA and 5-HT, respectively. OBJECTIVE: To evaluate whether expression of DAT and SERT in the striatum could lead to pathophysiological change in TS rat model. MATERIALS AND METHODS: Twenty-four Wistar male rats were randomly allocated to: TS model group (n=12) and control group (n=12). The stereotypy counts were recorded during the 2-week period of inducing TS rat models. The levels of DA and 5-HT in striatum homogenate were measured by ELISA. The protein and mRNA expression of DAT and SERT in the striatum were tested respectively by Immunofluorescence, Western blot and quantitative real-time PCR. Results : ANOVA analysis indicated that the stereotypy scores were much higher in the TS model group than in the control group at different time points (P<0.01). By ELISA analysis, the DA concentration in striatum homogenate was higher in the TS model group (130.92 +/- 25.60 ng/mL) than in the control group (101.00 +/- 20.14 ng/mL) (P<0.01), but 5-HT concentration in striatum was found to be lower in the TS model group (59.79 +/- 14.73 ng/mL) compared to the control group (77.01 +/- 14.05 ng/mL) (P<0.05). Analysis of protein and mRNA levels revealed a lower expression of DAT, concomitant with a higher expression of SERT in striatum of the TS model group than in the control group. CONCLUSIONS: Lower expression in DAT, concomitant with higher expression in SERT could participate in the pathophysiology of TS.

Factors influencing HIV infection in men who have sex with men in China.

To identify risk factors for HIV infection among men who have sex with men (MSM) and to provide a theoretical basis for prevention interventions. Between December 2011 and August 2012, a case-control study was conducted among MSM who underwent voluntary counselling and testing for HIV. Confirmed HIV-positive MSM were included in the case group, and HIV-negative MSM were included in the control group. Information on possible risk factors was collected by a survey questionnaire and a qualitative interview. The results of a conditional logistic regression showed that the following were influencing factors for HIV infection: average monthly income between 2001 and 3000 Yuan (odds ratio (OR)=6.341, 95% CI: 1.714-12.544), only sometimes using condoms when having anal sex with men in the last 6 months (OR=7.601, 95% CI: 1.359-23.083), having HIV-positive sex partners (OR=5.273, 95% CI: 1.572-17.691), rectal trauma with bleeding in the last 6 months (OR=2.947, 95% CI: 1.308-6.638), not using condoms at last sexual encounter (OR=1.278, 95% CI: 1.012-5.595), engaging in commercial sex (OR=5.925, 95% CI: 1.923-13.890) and having more than 16 sex partners in the last 6 months (OR=1.175, 95% CI: 1.021-1.353). These seven factors were the risk factors of HIV infection (OR>1). However, having anal sex less than 10 times in the previous 1 month (OR=0.002, 95% CI: 0.000-0.287) was a protective factor against HIV infection among MSM (OR<1), and insertive (OR=0.116, 95% CI: 0.000-0.236) (OR<1) anal intercourse influenced HIV infection. Interventions should be targeted at MSM whose average monthly income is between 2001 and 3000 Yuan, and who engage in commercial sex. In addition, the importance of using condoms at every sexual encounter should be emphasised in health education, as should the treatment of rectal trauma with bleeding. Finally, MSM should decrease the number of sex partners and frequency of anal sex to decrease the rate of HIV infection.

Preparation of 4,4'-bis-(carboxyl phenylazo)-dibenzo-18-crown-6 dye and its application on ratiometric colorimetric recognition to Hg2+.

A multifunctional dye, 4,4'-bis-(carboxyl phenylazo)-dibenzo-18-crown-6 dye (BCADC) was designed and prepared via diazotization and coupling reaction of dibenzo-18-crown-6 with p-amino benzoic acid. The dye, combining crown ether ring, azo and carboxyl group, exhibits well-defined Hg(2+)-selective ratiometric colorimetric behavior, with the maximum absorbance peak changing from 354 nm to 408 nm exclusively. Under the optimum conditions, the recognition to Hg(2+) has a linear range of 2.5-58×10(-7) mol L(-1) with a 0.9978 correlation coefficient. The method was applied to analyse 3 environmental water samples with a detection limit of 2.9×10(-8) mol L(-1) and a relative standard deviation (R.S.D.) lower than 3.7% (n=5). The action mechanism between BCADC and metal ions was discussed by means of Job's plots and theoretical calculations.