Inhibition of HMGB1 improves experimental mice colitis by mediating NETs and macrophage polarization

OBJECTIVE

Inflammatory bowel disease (IBD) is listed by the World Health Organization as one of the modern intractable diseases. High mobility histone box 1 (HMGB1), originally described as a non-histone nucleoprotein involved in transcriptional regulation, was later identified as a pro-inflammatory cytokine that may contribute to the pathogenesis of inflammatory diseases such as IBD. Neutrophil extracellular traps (NETs) play an important role in the pathophysiology of IBD The aim of this study was to investigate the role of HMGB1 in experimental colitis mice and its potential mechanisms of action.

METHODS

We first constructed the experimental colitis mouse model. Intervention of mice by rhHMGB1 supplementation or HMGB1 inhibition. The pathological morphology of the colon was observed using HE staining. Apoptosis of colonic tissue intestinal epithelial cells was evaluated using Tunel assay. The expression of HMGB1, ZO-1 and occludin in colon tissue was detected by immunohistochemistry, ELISA and western-blot. We also assessed the effects of HMGB1 on colonic injury, NETs content, macrophage polarization and inflammatory cells in mice. The regulatory effect of HMGB1 inhibition on NETs was assessed by combining DNase I.

RESULTS

Inhibition of HMGB1 significantly reduced the inflammatory model in experimental colitis mice, as evidenced by reduced body weight, increased colonic length, reduced DAI scores and apoptosis, reduced inflammatory response, and improved colonic histopathological morphology and intestinal mucosal barrier function. Meanwhile, inhibition of HMGB1 was able to reduce the expression of CD86, citH3 and MPO and increase the expression of CD206 in the colonic tissue of mice. In addition, DNase I intervention was also able to improve colonic inflammation in mice. And the best effect was observed when DNase I and inhibition of HMGB1 were intervened together.

CONCLUSION

Inhibition of HMGB1 ameliorates IBD by mediating NETs and macrophage polarization.

Sema3C Signaling is an Alternative Activator of the Canonical WNT Pathway in Glioblastoma

PURPOSE/OBJECTIVE(S)

Wnt signaling maintains normal and cancer stem cells. The Wnt pathway is frequently dysregulated in many cancers, underscoring it as a therapeutic target. Although Wnt inhibitors appear promising in many preclinical studies, they have failed uniformly in clinical trials. Molecular mechanisms of resistance are poorly defined. Further dissection of the precise mechanisms of Wnt pathway activation in specific tumor types is needed to develop new Wnt pathway inhibitors with less toxicity. Here, we identify an alternative activator of the Wnt pathway that may mediate resistance to upstream Wnt inhibition in glioblastoma.

MATERIALS/METHODS

Glioma stem-like cells (GSCs) were enriched in defined media. GSCs were transduced with lentiviruses to knockdown or overexpress Sema3C or Wnt pathway components. Cell viability, proliferation, apoptosis, and self-renewal were assessed. Expression of Sema3C and Wnt pathway components were assessed in GSCs, mouse models of GBM, and human glioblastoma by qPCR, Western blot, and/or immunostaining. Beta-catenin subcellular localization was assessed by cell fractionation and immunofluorescence. GSC-derived orthotopic models of GBM were used to assess the impact of genetic or pharmacologic inhibition of Sema3C or Wnt pathway components alone or in combination on tumor growth and animal survival.

RESULTS

The axonal guidance protein Sema3C promotes the tumorigenicity of GSCs through binding its NRP/PlxnD1 receptor complex leading to Rac1 activation. Sema3C signaling directs beta-catenin nuclear accumulation in a Rac1-dependent process, leading to transactivation of Wnt target genes. Sema3C-driven Wnt signaling occurred despite suppression of Wnt ligand secretion, suggesting that Sema3C may drive canonical Wnt signaling independent of Wnt ligand binding. In human glioblastoma, Sema3C expression and Wnt pathway activation were highly concordant. In a mouse model of glioblastoma, combined depletion of Sema3C and beta-catenin partner TCF1 extended animal survival more than single target inhibition alone.

CONCLUSION

Sema3C signaling may represent an alternative mechanism of WNT pathway activation even when WNT ligand-receptor interaction is inhibited. Since Sema3C is overexpressed in >85% glioblastoma and is used to maintain GSCs but not normal neural progenitor cells, this pathway may represent a major mechanism of Wnt pathway activation and resistance to upstream Wnt pathway inhibitors in GSCs. Our data provide a therapeutic strategy to achieve clinically significant Wnt pathway inhibition in GSCs potentially without the toxicity of currently available WNT inhibitors.

Radiomics-based machine-learning method for prediction of distant metastasis from soft-tissue sarcomas

AIM

To construct and validate a radiomics-based machine-learning method for preoperative prediction of distant metastasis (DM) from soft-tissue sarcoma.

MATERIALS AND METHODS

Seventy-seven soft-tissue sarcomas were divided into a training set (n=54) and a validation set (n=23). The performance of three feature selection methods (ReliefF, least absolute shrinkage and selection operator [LASSO], and regularised discriminative feature selection for unsupervised learning [UDFS]) and four classifiers, random forest (RF), logistic regression (LOG), K nearest neighbour (KNN), and support vector machines (SVMs), were compared for predicting the likelihood of DM. To counter the imbalance in the frequencies of DM, each machine-learning method was trained first without subsampling, then with the synthetic minority oversampling technique (SMOTE). The performance of the radiomics model was assessed using area under the receiver-operating characteristic curve (AUC) and accuracy (ACC) values.

RESULTS

The performance of the LASSO and SVM algorithm combination used with SMOTE was superior to that of the algorithm combination alone. The combination of SMOTE with feature screening by LASSO and SVM classifiers had an AUC of 0.9020 and ACC of 91.30% in the validation dataset.

CONCLUSION

A machine-learning model based on radiomics was favourable for predicting the likelihood of DM from soft-tissue sarcoma. This will help decide treatment strategies.

Assessment of serum Golgi protein 73 as a biomarker for the diagnosis of significant fibrosis in patients with chronic HBV infection

Transient elastography (TE) is accurate in staging fibrosis noninvasively. However, a reliable serum biomarker with comparable accuracy is also important, especially when TE is unreliable/unavailable. Therefore, we aimed to evaluate the diagnostic performance of serum Golgi protein 73 (GP73) for significant fibrosis in patients with chronic HBV infection. A total of 801 patients with chronic liver disease (CLD; 492 chronic HBV infection and 309 non-HBV liver disease) with liver biopsy performance were enrolled. Healthy controls (n = 180) and hepatocellular carcinoma (HCC) patients (n = 85) were included for comparisons. Liver biopsy was used as the reference method for fibrosis staging. Serum GP73 level was measured in duplicate in double-blind fashion. Serum GP73 was highest in HCC but also significantly higher in chronic hepatitis B than in healthy controls. The elevation of serum GP73 in non-HCC patients was significantly associated with the presence of significant fibrosis independently of ALT level, liver stiffness (LS) value, inflammation grade and other confounding factors. The diagnostic performance of serum GP73 was accurate in antiviral-naïve HBV patients (area under the receiver operating curve [AUROC], 0.76 95% CI: 0.72-0.81) but not in patients with ongoing antiviral treatment (AUROC, 0.60). The utility of serum GP73 was also confirmed in non-HBV CLD (AUROC, 0.80 95% CI: 0.75-0.85). Serum GP73 was comparable to LS (AUROC, 0.78 95% CI: 0.73-0.82) and significantly better than AST to platelet ratio index (APRI) (AUROC, 0.67 95% CI: 0.62-0.72) and FIB-4 (AUROC, 0.68 95% CI: 0.63-0.73). In conclusion, serum GP73 is an accurate serum marker for significant fibrosis in chronic HBV infection, with higher accuracy than APRI and FIB-4. Serum GP73 is potentially a complementary tool for TE when evaluating the necessity of antiviral treatment, particularly in patients without definite antiviral indication.

Salinomycin enhances doxorubicin sensitivity through reversing the epithelial-mesenchymal transition of cholangiocarcinoma cells by regulating ARK5

Chemotherapy response rates in patients with cholangiocarcinoma remain low, primarily due to the development of drug resistance. Epithelial-mesenchymal transition (EMT) of cancer cells is widely accepted to be important for metastasis and progression, but it has also been linked to the development of chemoresistance. Salinomycin (an antibiotic) has shown some potential as a chemotherapeutic agent as it selectively kills cancer stem cells, and has been hypothesized to block the EMT process. In this study, we investigated whether salinomycin could reverse the chemoresistance of cholangiocarcinoma cells to the chemotherapy drug doxorubicin. We found that combined salinomycin with doxorubicin treatment resulted in a significant decrease in cell viability compared with doxorubicin or salinomycin treatment alone in two cholangiocarcinoma cell lines (RBE and Huh-28). The dosages of both drugs that were required to produce a cytotoxic effect decreased, indicating that these two drugs have a synergistic effect. In terms of mechanism, salinomycin reversed doxorubicin-induced EMT of cholangiocarcinoma cells, as shown morphologically and through the detection of EMT markers. Moreover, we showed that salinomycin treatment downregulated the AMP-activated protein kinase family member 5 (ARK5) expression, which regulates the EMT process of cholangiocarcinoma. Our results indicated that salinomycin reversed the EMT process in cholangiocarcinoma cells by inhibiting ARK5 expression and enhanced the chemosensitivity of cholangiocarcinoma cells to doxorubicin. Therefore, a combined treatment of salinomycin with doxorubicin could be used to enhance doxorubicin sensitivity in patients with cholangiocarcinoma.

Change in serum TSH levels within the reference range was associated with variation of future blood pressure: a 5-year follow-up study

Controversy exists on the relationship between serum thyrotropin (TSH) and blood pressure, and only a few prospective studies are available up to now. The study aimed to investigate the association between serum TSH within the reference range and blood pressure through a 5-year follow-up study. A total of 623 subjects with normal TSH were followed up for 5 years, including the measurement of demographic data, blood pressure, height, weight and serum TSH. Finally, 531 subjects were included in this prospective study. Body mass index (BMI), prevalence of hypertension, and systolic and diastolic blood pressure were all higher at follow-up than at baseline. Adjusted for age, gender, smoking status, BMI and homoeostasis model assessment of insulin resistance (HOMA-IR) at baseline, multiple linear regression analyses found no relationship between serum TSH at baseline and levels of blood pressure at follow-up, but the changes in serum TSH levels during follow-up was positively associated with the changes in systolic blood pressure (B=2.134, P<0.05), which became more significant in women but not significant in men. The change of systolic blood pressure in group of TSH increase >0.5 mIU l^-1 was significantly higher than in group of TSH decrease >0.5 mIU l^-1 within reference, after adjusting for age, gender, smoking status, BMI and HOMA-IR at baseline. This result became more significant in women, but no statistical significance was observed in men. Co-variation with serum TSH levels and blood pressure was observed during 5-year follow-up among people with normal TSH.

Potential involvement of placental AhR in unexplained recurrent spontaneous abortion

Recurrent spontaneous abortion (RSA) is a common complication of pregnancy. Recent studies have demonstrated that the aryl hydrocarbon receptor (AhR) might play important roles in establishing and maintaining early pregnancy. In this study, we found that placental AhR protein levels were significantly lower and placental CYP1A1 mRNA levels were higher in unexplained RSA (URSA) patients than in control subjects. The results of immunohistochemical analyzes showed that placental AhR was expressed in syncytiotrophoblast cells and that the level of AhR was markedly lower in these cells in URSA subjects than in control subjects. β-Naphthoflavone (β-NF, an AhR ligand) at 5μM significantly inhibited proliferation and migration in HTR-8/SVneo cells and was associated with the activation of AhR. Moreover, overexpressing AhR in JAR cells significantly increased CYP1A1 mRNA levels and inhibited cell migration. These results indicate that AhR is highly activated in URSA placentas and that the activation of AhR in the placenta might impair trophoblast cell proliferation and migration, possibly leading to the occurrence of URSA.

IL-17 deficiency attenuates allograft injury and prolongs survival in a murine model of fully MHC-mismatched renal allograft transplantation

IL-17 is a pro-inflammatory cytokine implicated in the pathogenesis of inflammatory and autoimmune diseases. However the role of IL-17 in renal allograft rejection has not been fully explored. Here, we investigate the impact of IL-17 in a fully MHC-mismatched, life-sustaining, murine model of kidney allograft rejection using IL-17 deficient donors and recipients (IL-17(-/-) allografts). IL-17(-/-) allografts exhibited prolonged survival which was associated with reduced expression of the Th1 cytokine IFN-γ and histological attenuation of acute and chronic allograft rejection, as compared to wild-type allograft recipients. Results were confirmed in WT allograft recipients treated with an IL-17 blocking antibody. Subsequent experiments using either donors or recipients deficient in IL-17 showed a trend towards prolongation of survival only when recipients were IL-17(-/-) . Administration of a depleting anti-CD25 antibody to IL-17(-/-) recipients abrogated the survival advantage conferred by IL-17 deficiency, suggesting the involvement of a CD4(+) CD25(+) T cell regulatory mechanism. Therefore, IL-17 deficiency or neutralization was protective against the development of kidney allograft rejection, which may be mediated by impairment of Th1 responses and/or enhanced protection by Tregs.

TRPV2 in the development of experimental colitis

Colitis is still a significant disease challenge in humans, but its underlying mechanism remains to be fully elucidated. The transient receptor potential vanilloid (TRPV) ion channel plays an important pathological role in host immunity, as deficiency of TRPV compromises host defence in vivo and in vitro. Using a DSS-induced colitis mouse model, the function of TRPV2 in the development of colitis was investigated, utilizing TRPV2(-/-) and Wt mice. Less severe colitis was observed in TRPV2(-/-) , compared to that of Wt mice, at the clinical, histopathological and immunohistochemical levels. Compared to Wt mice, reduced severity of colitis in TRPV2(-/-) mice may be due to less intestinal inflammation via reduced recruitment of macrophages. The TRPV2 pathway contributes to the development of colitis. These data provide useful information for potential therapeutic intervention in colitis patients.

Pilot-scale comparison of four duckweed strains from different genera for potential application in nutrient recovery from wastewater and valuable biomass production

The application potential of four duckweed strains from four genera, Wolffia globosa 0222, Lemna japonica 0223, Landoltia punctata 0224 and Spirodela polyrhiza 0225, were compared in four parallel pilot-scale wastewater treatment systems for more than 1 year. The results indicated that each duckweed strain had unique potential advantages. Unlike L. japonica 0223 and La. punctata 0224, which grow throughout the year, S. polyrhiza 0225 and W. globosa 0222 do not survive cold weather. For year round performance, L. japonica 0223 was best not only in dry biomass production (6.10 g·m(-2) ·day(-1) ), but also in crude protein (35.50%), total amino acid (26.83%) and phosphorus (1.38%) content, plus recovery rates of total nitrogen (TN), total phosphorus (TP) and CO2 (0.31, 0.085 and 7.76 g·m(-2) ·day(-1) , respectively) and removal rates of TN and TP (0.66 and 0.089 g·m(-2) ·day(-1) , respectively). This strongly demonstrates that L. japonica 0223 performed best in wastewater treatment and protein biomass production. Under nutrient starvation conditions, La. punctata 0224 had the highest starch content (45.84%), dry biomass production (4.81 g·m(-2) ·day(-1) ) and starch accumulation (2.9 g·m(-2) ·day(-1) ), making it best for starch biomass production. W. globosa 0222 and S. polyrhiza 0225 showed increased flavonoid biomass production, with higher total flavonoid content (5.85% and 4.22%, respectively) and high dominant flavonoids (>60%). This study provides useful information for selecting the appropriate local duckweed strains for further application in wastewater treatment and valuable biomass production.

Repeated exposure to a tone transiently alters spectral tuning bandwidth of neurons in the central nucleus of inferior colliculus in juvenile rats

Early acoustic experience changes tonal frequency tuning in the inferior colliculus (IC) and the primary auditory cortex. The contributions of IC plasticity to cortical frequency map reorganization are not entirely clear. While most cortical plasticity studies exposed animals to pulsed tones, studies of IC plasticity used either noise or a continuous tone. Here we compared the effects of repeated exposure to single-frequency tone pips on cortical and IC frequency representations in juvenile rats. We found that while tone exposure caused a long-lasting increase in cortical representations of the exposure frequency, changes to IC neurons were limited to a transient narrowing of tuning bandwidth. These results suggest that previously documented cortical frequency map reorganization does not depend on similar changes in the subcortical auditory nuclei.