Causal associations of cytokines and growth factors with cholelithiasis: a bidirectional Mendelian randomization study

BACKGROUND

It has been reported that patients with cholelithiasis may have changes in levels of cytokines and growth factors, while their causal relationships were still unclear.

METHODS

This study was a bidirectional Mendelian randomization (MR) study. Datasets of 41 circulation cytokines and growth factors and the data on cholelithiasis were obtained. Six steps of strict instrumental variable filtration were set, and inverse-variance weighted analysis, MR-Egger regression, and weighted median test were used to identify the causal relationships. Benjamini-Hochberg method was used to adjust the P-values.

RESULTS

After adjustments of P-values, four cytokines and growth factors were still causally associated with cholelithiasis significantly: interleukin 2 receptor alpha (adjusted P: 4.59E-02), interleukin 8 (adjusted P: 1.09E-02), monocyte-specific chemokine 3 (adjusted P: 2.73E-04), and stem cell factor (adjusted P: 2.73E-04). In the reverse MR analysis, no significant causal relationship was detected after adjustment.

CONCLUSIONS

Four cytokines and growth factors, including interleukin 2 receptor alpha, interleukin 8, monocyte-specific chemokine 3, and stem cell factor, were proven to relate to cholelithiasis causally and unidirectionally.

[Assessment of MS-Score and HScore in timeliness of diagnosis of macrophage activation syndrome associated with adult-onset Still's disease]

The data of 33 patients with adult-onset still's disease (AOSD)-associated macrophage activation syndrome (MAS) were retrospectively collected from January 2013 to December 2020 in Peking Union Medical College Hospital. Hemophagocytic lymphohistiocytosis (HLH)-2004 criteria, macrophage activation syndrome/juvenile idiopathic arthritis (MS-Score) and hemophagocytic syndrome diagnostic score (HScore) were used to diagnose AOSD-associated MAS, respectively. The time of diagnosis of AOSD-associated MAS by MS-Score was 19.0 (4.5, 31.0) days [M (Q₁,Q₃)] earlier than by HLH-2004 criteria, and 13.5 (0.5, 21.5) days earlier than by HScore (both P<0.05). The difference was not statistically significant between the time of diagnosis of AOSD-associated MAS by Hscore and by HLH-2004 criteria (P>0.05). There was significant difference among the three criteria (P<0.001). MS-Score can be used to diagnose AOSD-associated MAS earlier than HLH-2004 criteria, while the timeliness of HScore is not certain.

Circular RNA AKT3 governs malignant behaviors of esophageal cancer cells by sponging miR-17-5p

BACKGROUND

Recent studies have demonstrated that circular RNA AKT3 (circAKT3) plays a crucial role in regulating the malignant phenotypes of tumor cells. However, the potential effects of circAKT3 on esophageal cancer have not been investigated.

AIM

To illuminate the role of circAKT3 in malignant behaviors of esophageal cancer cells and its underlying mechanism.

METHODS

Clinical samples were collected to detect the expression of circAKT3. The role of circAKT3 in proliferation, migration, invasion, and apoptosis of esophageal cancer cells was evaluated using Cell Counting Kit-8, wound healing assays, Transwell assays, and fluorescence analysis, respectively. The target of circAKT3 was screened and identified using an online database and luciferase reporter assay. A xenograft nude mouse model was established to investigate the role of circAKT3 in vivo.

RESULTS

In vitro assays showed that proliferative, migratory, and invasive capacities of esophageal cancer cells were significantly enhanced by circAKT3 overexpression. Furthermore, miR-17-5p was screened as the target of circAKT3, and miR-17-5p antagonized the effects of circAKT3 on esophageal cancer cells. Moreover, we identified RHOC and STAT3 as the direct target molecules of miR-17-5p, and circAKT3 facilitated expression of RHOC and STAT3 by inhibiting miR-17-5p. In vivo assays showed circAKT3 knockdown inhibited growth of esophageal cancer.

CONCLUSION

CircAKT3 contributed to the malignant behaviors of esophageal cancer in vitro and in vivo by sponging miR-17-5p thus providing a potential target for treatment of esophageal cancer.

[Experience of diagnosis and treatment of lingual thyroglossal duct cyst]

Objective: To explore and analyse the imaging examinations, clinical presentation, operative methods complication and the surgical outcomes of lingual thyroglossal duct cyst (LTGDC) . Methods: The clinical data of 30 patients with LTGDC were analyzed retrospectively from January 2015 to October 2018 at the First Affiliated Hospital of Zhengzhou University. Results: 30 cases were treated with endoscopic coblation cauterization firstly. Follow-up for 7.5-45.0(25.4) months showed that 25 cases had no recurrence, 2 cases had no connection, 2 cases had recurrence once, and 1 cases had recurrence twice,the recurrence rate was 10.7%(3/28).Two patients recurred once, and the last operation was performed with endoscopic coblation cauterization, and no recurrence was found in the follow-up of 1 year; one patient recurred twice underwent the last operation with Sistrunk operation, and no recurrence was found in the follow-up of 1 year. There was no pharyngeal fistula and hoarseness in 28 patients. Conclusions: For LTGDC,especially, those of the first-episode children, endoscopic coblation cauterization is the first choice. Recurrent LTGDC can be treated by endoscopic coblation cauterization, so that patients with multiple recurrences can be considered the Sistrunk operation.

MTA1 Promotes Hepatocellular Carcinoma Progression by Downregulation of DNA-PK-Mediated H1.2T146 Phosphorylation

Global incidence and mortality associated with hepatocellular carcinoma (HCC) is steadily increasing. Metastasis-associated 1 (MTA1) can induce tumorigenesis and metastatic progression in HCC. However, the mechanistic details of MTA1-mediated regulation of HCC has not been completely defined. Epigenetic histone modification is closely related to tumor development. Histone cluster 1 H1 family member c (H1.2) is important for epigenetic histone modification and chromatin remodeling; however, whether it has a role in HCC tumorigenesis is not known. In the current study, we confirmed that MTA1 promoted HCC cell growth and migration. Our results further show that MTA1 inhibited the phosphorylation of histone cluster 1 H1 family member c (H1.2) at threonine-146 residue (T146) (H1.2^T146ph). MTA1 inhibited H1.2^T146ph by mediating proteasomal degradation of the DNA protein kinase (DNA-PK). Pharmacological inhibition of proteasomal degradation of DNA-PK or genetic ablation of E3 ligase mouse double minute 2 (MDM2) rescued expression of DNA-PK, and subsequent phosphorylation of H1.2. MTA1's role in HCC was inhibited by ectopic expression of H1.2^T146ph in HCC cell lines. Our results showed that H1.2^T146ph can bind to MTA1 target genes. Collectively, our study confirms that MTA1 functions as an oncogene and promotes HCC progression. The epigenetic histone modifier H1.2^T146ph exerts critical role in the regulation of MTA1-induced tumorigenesis. MTA1 regulates posttranslational activation of H1.2 by regulating the cognate kinase, DNA-PK, via the ubiquitin proteasome system. MTA1 expression was inversely correlated to both DNA-PK and phosphorylated H1.2 in HCC tissue specimens compared to tumor adjacent normal hepatic tissue, revealing that the MTA1/MDM2/DNA-PK/H1.2 is an important therapeutic axis in HCC.

PTEN-induced kinase 1-induced dynamin-related protein 1 Ser637 phosphorylation reduces mitochondrial fission and protects against intestinal ischemia reperfusion injury

BACKGROUND

Intestinal ischemia reperfusion (I/R) occurs in various diseases, such as trauma and intestinal transplantation. Excessive reactive oxygen species (ROS) accumulation and subsequent apoptotic cell death in intestinal epithelia are important causes of I/R injury. PTEN-induced putative kinase 1 (PINK1) and phosphorylation of dynamin-related protein 1 (DRP1) are critical regulators of ROS and apoptosis. However, the correlation of PINK1 and DRP1 and their function in intestinal I/R injury have not been investigated. Thus, examining the PINK1/DRP1 pathway may help to identify a protective strategy and improve the patient prognosis.

AIM

To clarify the mechanism of the PINK1/DRP1 pathway in intestinal I/R injury.

METHODS

Male C57BL/6 mice were used to generate an intestinal I/R model via superior mesenteric artery occlusion followed by reperfusion. Chiu’s score was used to evaluate intestinal mucosa damage. The mitochondrial fission inhibitor mdivi-1 was administered by intraperitoneal injection. Caco-2 cells were incubated in vitro in hypoxia/reoxygenation conditions. Small interfering RNAs and overexpression plasmids were transfected to regulate PINK1 expression. The protein expression levels of PINK1, DRP1, p-DRP1 and cleaved caspase 3 were measured by Western blotting. Cell viability was evaluated using a Cell Counting Kit-8 assay and cell apoptosis was analyzed by TUNEL staining. Mitochondrial fission and ROS were tested by MitoTracker and MitoSOX respectively.

RESULTS

Intestinal I/R and Caco-2 cell hypoxia/reoxygenation decreased the expression of PINK1 and p-DRP1 Ser637. Pretreatment with mdivi-1 inhibited mitochondrial fission, ROS generation, and apoptosis and ameliorated cell injury in intestinal I/R. Upon PINK1 knockdown or overexpression in vitro, we found that p-DRP1 Ser637 expression and DRP1 recruitment to the mitochondria were associated with PINK1. Furthermore, we verified the physical combination of PINK1 and p-DRP1 Ser637.

CONCLUSION

PINK1 is correlated with mitochondrial fission and apoptosis by regulating DRP1 phosphorylation in intestinal I/R. These results suggest that the PINK1/DRP1 pathway is involved in intestinal I/R injury, and provide a new approach for prevention and treatment.

Effects of long non-coding RNA Opa-interacting protein 5 antisense RNA 1 on colon cancer cell resistance to oxaliplatin and its regulation of microRNA-137

BACKGROUND

The incidence of colon cancer (CC) is currently high, and is mainly treated with chemotherapy. Oxaliplatin (L-OHP) is a commonly used drug in chemotherapy; however, long-term use can induce drug resistance and seriously affect the prognosis of patients. Therefore, this study investigated the mechanism of Opa-interacting protein 5 antisense RNA 1 (OIP5-AS1) on L-OHP resistance by determining the expression of OIP5-AS1 and microRNA-137 (miR-137) in CC cells and the effects on L-OHP resistance, with the goal of identifying new targets for the treatment of CC.

AIM

To study the effects of long non-coding RNA OIP5-AS1 on L-OHP resistance in CC cell lines and its regulation of miR-137.

METHODS

A total of 114 CC patients admitted to China-Japan Union Hospital of Jilin University were enrolled, and the expression of miR-137 and OIP5-AS1 in tumor tissues and corresponding normal tumor-adjacent tissues was determined. The influence of OIP5-AS1 and miR-137 on the biological behavior of CC cells was evaluated. Resistance to L-OHP was induced in CC cells, and their activity was determined and evaluated using cell counting kit-8. Flow cytometry was used to analyze the apoptosis rate, Western blot to determine the levels of apoptosis-related proteins, and dual luciferase reporter assay combined with RNA-binding protein immunoprecipitation to analyze the relationship between OIP5-AS1 and miR-137.

RESULTS

OIP5-AS1 was up-regulated in CC tissues and cells, while miR-137 was down-regulated in CC tissues and cells. OIP5-AS1 was inversely correlated with miR-137 (P < 0.001). Silencing OIP5-AS1 expression significantly hindered the proliferation, invasion and migration abilities of CC cells and markedly increased the apoptosis rate. Up-regulation of miR-137 expression also suppressed these abilities in CC cells and increased the apoptosis rate. Moreover, silencing OIP5-AS1 and up-regulating miR-137 expression significantly intensified growth inhibition of drug-resistant CC cells and improved the sensitivity of CC cells to L-OHP. OIP5-AS1 targetedly inhibited miR-137 expression, and silencing OIP5-AS1 reversed the resistance of CC cells to L-OHP by promoting the expression of miR-137.

CONCLUSION

Highly expressed in CC, OIP5-AS1 can affect the biological behavior of CC cells, and can also regulate the resistance of CC cells to L-OHP by mediating miR-137 expression.

Integrative analysis of the inverse expression patterns in pancreas development and cancer progression

BACKGROUND

As the malignant tumor, pancreatic cancer with a meager 5-years survival rate has been widely concerning. However, the molecular mechanisms that result in malignant transformation of pancreatic cells remain elusive.

AIM

To investigate the gene expression profiles in normal or malignant transformed pancreas development.

METHODS

MaSigPro and ANOVA were performed on two pancreas development datasets downloaded from the Gene Expression Omnibus database. Six pancreatic cancer datasets collected from TCGA database were used to establish differentially expressed genes related to pancreas development and pancreatic cancer. Moreover, gene clusters with highly similar interpretation patterns between pancreas development and pancreatic cancer progression were established by self-organizing map and singular value decomposition. Additionally, the hypergeometric test was performed to compare the corresponding interpretation patterns. Abnormal regions of metabolic pathway were analyzed using the Sub-pathway-GM method.

RESULTS

This study established the continuously upregulated and downregulated genes at different stages in pancreas development and progression of pancreatic cancer. Through analysis of the differentially expressed genes, we established the inverse and consistent direction development-cancer pattern associations. Based on the application of the Subpathway-GM analysis, we established 17 significant metabolic sub-pathways that were closely associated with pancreatic cancer. Of note, the most significant metabolites sub-pathway was related to glycerophospholipid metabolism.

CONCLUSION

The inverse and consistent direction development-cancer pattern associations were established. There was a significant correlation in the inverse patterns, but not consistent direction patterns.

Long noncoding RNA CCAT2 functions as a competitive endogenous RNA to regulate FOXC1 expression by sponging miR-23b-5p in lung adenocarcinoma

Long noncoding RNA (lncRNA) may regulate the process of tumor formation. Although lncRNA CCAT2 has been identified as a key point in many diseases, its pathophysiological mechanism in lung adenocarcinoma remains unknown. We measured the expression level of CCAT2 in lung adenocarcinoma cells and normal lung epithelial cell line BEAS-2B by quantitative real-time polymerase chain reaction (qRT-PCR). As well, cell migration and proliferation were detected by transwell detection and CCK8 assay. At the same time, the new target point of CCAT2 was confirmed with bioinformatics analysis and dual-luciferase reporter assay. In addition, potential mechanisms were studied by Western blot analysis and RNA immunoprecipitation (RIP) analysis. The expression of CCAT2 was upregulated obviously in lung adenocarcinoma cells. Cell function analysis showed that upregulation of CCAT2 significantly promoted cell proliferation and migration, and reduction of CCAT2 inhibited cell migration and proliferation. In addition, CCAT2 positively regulated the expression of FOXC1 by competitive binding with miR-23b-5p. These findings indicated that CCAT2 may act as a competitive endogenous RNA (ceRNA) to regulate FOXC1 expression by competitively binding miR-23b-5p in lung adenocarcinoma.

Ubiquitin-specific protease 22 enhances intestinal cell proliferation and tissue regeneration after intestinal ischemia reperfusion injury

BACKGROUND

Intestinal ischemia reperfusion (I/R) injury is a serious but common pathophysiological process of many diseases, resulting in a high mortality rate in clinical practice. Ubiquitin-specific protease 22 (USP22) acts as regulator of cell cycle progression, proliferation, and tumor invasion. Depleted USP22 expression has been reported to contribute to arrested cell cycle and disrupted generation of differentiated cell types in crypts and villi. However, the role of USP22 in intestinal damage recovery has not been investigated. Therefore, elucidation of the underlying mechanism of USP22 in intestinal I/R injury may help to improve the tissue repair and patient prognosis in clinical practice.

AIM

To investigate the role of USP22 in intestinal cell proliferation and regeneration after intestinal I/R injury.

METHODS

An animal model of intestinal I/R injury was generated in male Sprague-Dawley rats by occlusion of the superior mesenteric artery followed by reperfusion. Chiu’s scoring system was used to grade the damage to the intestinal mucosa. An in vitro model was developed by incubating rat intestinal epithelial IEC-6 cells in hypoxia/reoxygenation conditions in order to simulate I/R in vivo. siRNA and overexpression plasmid were used to regulate the expression of USP22. USP22, Cyclin D1, and proliferating cell nuclear antigen (PCNA) expression levels were measured by Western blot analysis and immunohistochemistry staining. Cell survival (viability) and cell cycle were evaluated using the Cell Counting Kit-8 and flow cytometry, respectively.

RESULTS

USP22 expression was positively correlated with the expression levels of PCNA and Cyclin D1 both in vivo and in vitro, which confirmed that USP22 was involved in cell proliferation and intestinal regeneration after intestinal I/R injury. Decreased levels of Cyclin D1 and cell cycle arrest were observed in the USP22 knockdown group (P < 0.05), while opposite results were observed in the USP22 overexpression group (P < 0.05). In addition, increased expression of USP22 was related to improved intestinal pathology or IEC-6 cell viability after I/R or hypoxia/reoxygenation. These results suggested that USP22 may exert a protective effect on intestinal I/R injury by regulating cell proliferation and facilitating tissue regeneration.

CONCLUSION

USP22 is correlated with promoting intestinal cell proliferation and accelerating intestinal tissue regeneration after intestinal I/R injury and may serve as a potential target for therapeutic development for tissue repair during intestinal I/R injury.

Mechanism of TRIM25 mediated ubiquitination of metastasis associated protein (MTA) 1 in normal liver cells

Ninety percent of all cancer related deaths happen due to metastatic progression. One important protein facilitating metastatic progression in hepatocellular carcinoma (HCC) is the metastasis associated 1 protein (MTA-1). We have earlier shown that in the context of HCC and normal liver cell lines, HuH6 and THLE-2, respectively. MTA-1 protein is actively stabilized in HCC cell lines and actively degraded in normal liver cells. We had also shown that TRIM25 is the E3 ligase that interacts with and degrades MTA-1 protein in normal liver cells. However, the exact mechanism by which TRIM25 degrades MTA-1 protein has still not been elucidated. In the study, we used both in situ prediction algorithms and mass spectrometry based post-translational modification analysis to map the lysine residues in MTA-1 that are polyubiquitinated. Whereas UbPred algorithm revealed a combination of medium and low confidence sites, it revealed only one high confidence lysine (K98) residue. The hCKSAAP_UbSite algorithm also predicted K98 site. Mass spectrometry analysis also showed that K98 has ubiquitin modification. Immunofluorescence analysis showed that in normal liver cell line, THLE-2, which has high expression of TRIM25, ectopically expressed FLAG-tagged wild-type MTA-1 was actively degraded, but the K98R mutant MTA-1 was not. In vitro ubiquitination assay using recombinant wild-type and K98R mutant MTA-1 confirmed that MTA-1 is poly-ubiquitinated at K98 residue by TRIM25. The K98R mutant had a longer half-life than wild-type MTA-1 protein in an in vitro protein stability assay. We establish that TRIM25 ubiquitinates MTA-1 at lysine 98 and degrades it normal liver cells.

[Experience of diagnosis and treatment for congenital pyriform sinus fistula]

Objective: To evaluate the imaging features, clinical presentation, operative methods complication and the surgical outcomes of the congenital pyriform sinus fistula(CPSF). Methods: The clinical data of 185 patients with CPSF treated from January 2013 to October 2017 at the First Affiliated Hospital of Zhengzhou University were analyzed retrospectively. Results: The lesions were predominantly on the left side(170/185). Among 185 cases, 146 cases received endoscopic coblation cauterization, 27 cases had traditional open surgery, 8 cases underwent endoscopic coblation cauterization plus traditional open surgery, 2 cases for endoscopic chemocauterization, and 2 cases for endoscopic electrosection. Twenty-eight cases recurred, with a recurrence rate of 15.1%. Postoperative hoarseness occurred in 22 cases, disappeared within 0.5-6.0 months later. Conclusions: Patients with a history of recurrent cervical abscess should be highly suspect the existence of CPSF. Endoscopic coblation cauterization is a kind of surgical method with minimal injury, with low recurrence rate and low operative risk.

The E3 ligase for metastasis associated 1 protein, TRIM25, is targeted by microRNA-873 in hepatocellular carcinoma

Tumor metastasis accounts for 90% of all cancer-related deaths. Epithelial to mesenchymal transition (EMT) considered to be centrally important in acquired resistance to chemotherapy and in progression of tumors to secondary organs. One of the important mediators of metastatic progression in hepatocellular carcinoma (HCC) is the metastasis associated protein 1 (MTA-1). We have earlier shown that in the context of HCC and normal liver cell lines, MTA-1 protein is actively stabilized in HCC cell lines and actively degraded in normal liver cells. We have also shown that TRIM25 is the E3 ligase that interacts with and degrades MTA-1 protein. The identity of the factor regulating expression of TRIM25 in normal liver cells and HCC is unknown. In the current work we elucidate that microRNA (miR)- 873 targets TRIM25 in HCC cells. Both metagenomic analysis and quantification of miR-873 and TRIM25 in 25 HCC patients revealed an inverse correlation between the two in HCC patients with high miR-873 and low TRIM25 expression, respectively. The expression pattern was mimicked in the normal liver cells THLE-2 and the HCC cell line, HuH6. In vitro luciferase reporter assays confirmed TRIM25 as the target of miR-873. Transient transfection of HuH6 cells with an anti-miR-873 antagomir significantly decreased both transwell motility in these cells. Furthermore, in in vivo xenograft assays treatment with anti-miR-873 antagomir significantly decreased hepatic nodules formation. Cumulatively, our data indicate that suppression of TRIM25 expression by high levels of miR-873 dictates MTA1 protein upregulation in HCC.

Fish oil alleviates liver injury induced by intestinal ischemia/reperfusion via AMPK/SIRT-1/autophagy pathway

AIM

To evaluate whether fish oil (FO) can protect liver injury induced by intestinal ischemia/reperfusion (I/R) via the AMPK/SIRT-1/autophagy pathway.

METHODS

Ischemia in Wistar rats was induced by superior mesenteric artery occlusion for 60 min and reperfusion for 240 min. One milliliter per day of FO emulsion or normal saline was administered by intraperitoneal injection for 5 consecutive days to each animal. Animals were sacrificed at the end of reperfusion. Blood and tissue samples were collected for analyses. AMPK, SIRT-1, and Beclin-1 expression was determined in lipopolysaccharide (LPS)-stimulated HepG2 cells with or without FO emulsion treatment.

RESULTS

Intestinal I/R induced significant liver morphological changes and increased serum alanine aminotransferase and aspartate aminotransferase levels. Expression of p-AMPK/AMPK, SIRT-1, and autophagy markers was decreased whereas tumor necrosis factor-α (TNF-α) and malonaldehyde (MDA) were increased. FO emulsion blocked the changes of the above indicators effectively. Besides, in LPS-stimulated HepG2 cells, small interfering RNA (siRNA) targeting AMPK impaired the FO induced increase of p-AMPK, SIRT-1, and Beclin-1 and decrease of TNF-α and MDA. SIRT-1 siRNA impaired the increase of SIRT-1 and Beclin-1 and the decrease of TNF-α and MDA.

CONCLUSION

Our study indicates that FO may protect the liver against intestinal I/R induced injury through the AMPK/SIRT-1/autophagy pathway.

The ubiquitin ligase TRIM25 inhibits hepatocellular carcinoma progression by targeting metastasis associated 1 protein

Metastasis associated 1 protein (MTA1) is one of the prime facilitators of metastatic progression in all solid tumors including hepatocellular carcinoma (HCC). However, the underlying regulatory mechanism of MTA1 expression in HCC is not clear. In this study, we evaluated MTA1 transcript and protein expression in HCC and normal hepatic cell lines. The results revealed that MTA1 protein expression had a significantly increase in HCC cell line, HuH6, compared with that in normal hepatic cell line, THLE-2. Determination of protein half-life using cycloheximide (CHX) treatment did not reveal any statistically significant difference in protein turn-over rates between THLE-2 (3.3 ± 0.25 h) and HuH6 (3.6 ± 0.15 h) cell lines. MTA1 protein level was stabilized in THLE-2 cells after treatment with MG-132 to levels similar to those observed in HuH6 cells. Mass spectrometric analysis of FLAG immunoprecipitates of FLAG-MTA1 transfected THLE-2 cells after MG-132 treated revealed candidate ubiquitin ligases that were interacting with MTA1. RNAi-mediated silencing of each prospective ubiquitin ligase in THLE-2 cells indicated that knockdown of TRIM25 resulted in stabilization of MTA1 protein, indicating TRIM25 as a putative E3 ligase for MTA1. Coimmunoprecipitation of FLAG-tagged MTA1, but not IgG, in MG-132 treated and untreated THLE-2 cells cotransfected with either FLAG-MTA1 or Myc-TRIM25 revealed robust polyubiquitinated MTA1, confirming that the TRIM25 is the ubiquitin ligase for MTA1 degradation. Overexpression of TRIM25 in HuH6 and RNAi mediated silencing of TRIM25 in THLE-2 cells inhibited and increased the cell migration and invasion, respectively. Analysis of The Cancer Genome Atlas data for assessment of TRIM25 transcript level and MTA1 protein expression in 25 HCC patients confirmed an inverse correlation between the expression of TRIM25 and MTA1. Cumulatively, our data reveal a novel mechanism of post-translational to regulate MTA1 expression in normal hepatic cells, which is repressed in HCC. © 2017 IUBMB Life, 69(10):795-801, 2017.

HPV genotype analysis for women in Shaanxi Province of China

The aim of this study was to examine the subtype distribution of human papilloma virus (HPV) in women in the Shaanxi Province of China. A DNA chip, along with polymerase chain reaction amplification and reverse dot blot technology, was adopted to analyze the HPV genotypes of 22,937 cases of cervical cell specimens. The HPV infection rate was 18.70%, wherein high-risk, low-risk, and high- and low-risk multiple infection rates were 15.75, 2.96 and 1.91%, respectively. High-risk infections accounted for 84.20% of total infections. The rate of HPV infection in women with rural residence, high school education or less, a low income, or age over 40 years was significantly higher than that in the control group (negative HPV infection women). Of the 18 detected high-risk HPV subtypes, the most common in single infections were, in the order of prevalence, HPV16, 58, 18, 52, 33, and 56. For multiple high-risk infections, the most common subtypes in the order of prevalence were HPV16, 52, 58, 18, 56, and 33. Age was a factor in the rate of infection, as the 41-50-year age group had a significantly higher risk of infection than the other groups (P < 0.05). In multiple infections, double infections were common, accounting for 77.10% of multiple infections, and triple or more infections were more common in women aged 51-60 years. In Shaanxi Province, high-risk HPV infection in women was mainly attributed to rural residence, age over 40 years, low income, and low education level.

PACE4 regulates apoptosis in human pancreatic cancer Panc‑1 cells via the mitochondrial signaling pathway

Previous studies have demonstrated the overexpression of paired basic amino acid cleaving enzyme 4 (PACE4) mRNA in prostate cancer tissues. This overexpression is correlated with higher circulating protein levels in certain patients, however, the role of PACE4 in apoptosis and the potential molecular mechanisms of pancreatic cancer remain to be elucidated. The aim of the present study was to investigate the effect and potential molecular mechanisms of PACE4 on apoptosis in the Panc‑1 pancreatic cancer cell line. Cell proliferation was assessed using a Cell Counting Kit‑8 assay. Apoptotic nuclear shrinkage was monitored using Hoechst 33258 staining. Caspase‑3/7 activities were measured using a colorimetric caspase‑glo 3/7 assay. Alterations in protein expression were monitored using Western blot analysis. The results indicated that PACE4 small interfering (si)RNA inhibited cell proliferation and activated caspase‑3/7 activities. In addition, PACE4 siRNA significantly increased apoptosis via the activation of caspase‑3 and the downregulation of anti‑apoptotic proteins, X‑linked inhibitor of apoptosis protein and phosphorylated‑Akt. In addition, the results showed deregulation of the B cell lymphoma‑2 (Bcl‑2)-associated X protein/Bcl‑2 ratio which led to the release of cytochrome c following PACE4 siRNA transfection. In conclusion, PACE4 siRNA may exert antitumor activity through the mitochondrial pathway and is expected to be a promising therapeutic strategy for the treatment of pancreatic cancer.

Prevalence of human papillomavirus genotypes among women with cervical lesions in the Shaanxi Province of China

This study aimed to investigate human papilloma virus (HPV) genotypes among women with cervical lesions in Shaanxi Province, China, to obtain information regarding cervical lesion prevention and treatment. The study included 4508 HPV-positive subjects; cervical swab specimens were collected and tested for HPV infection status and HPV genotypes using polymerase chain reaction and reverse dot-blot hybridization. Women positive for HPV with cervical lesions, including chronic cervicitis, cervical intraepithelial neoplasia, and cervical squamous cell carcinoma (SCC), were examined; HPV-positive women with no cervical lesions were controls. Data were pooled and weighted estimates have been presented. For women with no cervical lesions and positive for one HPV genotype, HPV 52, 16, 58, 81, 33, and 56 were the most common; for multiple-HPV genotype infection, HPV 16, 52, 6, 18, 58, and 66 were the most common. Collectively, HPV 16, 58, 52, 18, 33, and 81 were the most common in women with cervical lesions. HPV 16 comprised 26.71% of single-genotype and 15.64% of multiple-genotype infections. The proportion of HPV-16-positive cases was 29.15%, which was the highest among all HPV genotypes (P < 0.01). Single-HPV genotype infection was the most common in cervical HPV infection (77.48%); infection with two HPV genotypes comprised 72.22% of multiple-genotype infections. The proportion of single-low-risk HPV genotype infections decreased with increase in cervical lesion severity; there were no single- or multiple-low-risk genotype HPV infections in cervical SCC patients. The proportion of multiple-genotype HPV infections with at least one high-risk genotype increased with cervical lesion severity.

Dihydromyricetin induces cell apoptosis via a p53-related pathway in AGS human gastric cancer cells

The aim of the present study was to determine the anti-proliferative and pro-apoptotic effects of dihydromyricetin (DHM) on the AGS human gastric cancer cells and their underlying mechanisms. The effects of DHM on AGS cells were evaluated by using 3-(4, 5-di-methylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), lactate dehydrogenase, and Annexin V/propidium iodide (PI) double-staining assays. The underlying mechanisms were determined by using quantitative real-time polymerase chain reaction. The results demonstrated that DHM significantly (P < 0.05) inhibited AGS cell proliferation and induced cell cytotoxicity in a dose- and time-dependent manner. Additionally, Annexin V/PI double-staining assay showed that DHM promoted cell apoptosis in both, early and late stages. Furthermore, DHM also regulated the expression of apoptotic genes such as p53 and B-cell lymphoma-2 (bcl-2) in a dose- and time-dependent manner. In conclusion, this is the first report demonstrating the anticancer and pro-apoptosis effects of DHM on AGS human gastric cancer cells. The results strongly suggest that DHM may be a potential therapeutic candidate for the treatment of gastric cancer.

A case of annular pancreas accompanied with intraductal papillary mucinous neoplasm-case report

OBJECTIVES

Annular pancreas is a rare congenital anomaly characterized by pancreatic tissues wrapping completely or incompletely around the descending duodenum. In most patients with annular pancreas, onset occurs in early childhood. Adults with annular pancreas are prone to duodenal ulcers and pancreatitis. Intraductal papillary mucinous neoplasm (IPMN) is a type of papillary mucinous secretory epithelial tumor, which originates in the main pancreatic duct and/or branch duct. We report a case of annular pancreas accompanied with intraductal papillary mucinous neoplasm.

METHODS

A 52-year-old male patient hospitalized due to recurrent upper abdominal pain for one and a half years was enrolled in this study.

RESULTS

One case of annular pancreas accompanied with intraductal papillary mucinous neoplasm which manifested as recurrent chronic pancreatitis was found. After pancreaticoduodenectomy, the patient died from uncontrollable gastrointestinal bleeding.

CONCLUSIONS

To the best of our knowledge, this is the first case in China and the second case worldwide of annular pancreas accompanied with IPMN in English literature.

Protective effects of icariin-mediated SIRT1/FOXO3 signaling pathway on intestinal ischemia/reperfusion-induced acute lung injury

Acute lung injury (ALI) is a common complication following intestinal ischemia/reperfusion (I/R) and is a major contributing factor to its high mortality rate. Sirtuin 1 (SIRT1), a NAD+-dependent deacetylase, has been reported to have an important role in apoptosis inhibition, oxidative stress resistance and cell lifespan extension through its deacetylation of forkhead box protein O3 (FOXO3). It has been demonstrated that icariin (ICA), a flavonoid extracted from Epimedium, upregulates SIRT1 expression. The aim of the present study was to examine whether ICA-mediated SIRT1/FOXO3 signaling pathway activation had a protective effect on intestinal I/R-induced ALI. The effects of ICA on intestinal I/R-induced ALI and its regulation of the SIRT1/FOXO3 signaling pathway on intestinal I/R-induced ALI were investigated in rats. The results demonstrated that ICA pretreatment markedly reduced intestinal I/R-induced ALI as indicated by histological alterations, including decreased tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), reduced oxidative stress, acetylated FOXO3 and B-cell lymphoma 2 (Bcl-2)-interacting mediator of cell death levels, and increased glutathione (GSH), GSH peroxidase, SIRT1, manganese superoxide dismutase and Bcl-2 levels in rat lung tissues. Furthermore, ICA pretreatment upregulated SIRT1 expression, which then downregulated FOXO3 acetylation. In conclusion, ICA exhibited significant protective effects in intestinal I/R-induced ALI. The protective effect of ICA may be attributed to the upregulation of SIRT1, which contributed to FOXO3 deacetylation and the modulation of downstream antioxidative and anti-apoptotic factors.

Accelerated healing by composites containing herb epimedium for osteoinductive regeneration

Porous composites composed of hydroxyapatite (HA), herb epimedium (EP), and chitosan (CS) were used to improve the repair of rabbit bone defects. The in vivo implantation of the HA/CS-EP showed that homogeneous bone formation occurred after 12 weeks' implantation and possessed good osteogenesis. The osteogenic process of the HA/CS-EP group was different from that of the HA/CS group. Direct bone formation of osteoblasts with HA/CS-EP as the matrix could be observed. Compared with the group filled with HA/CS, the group filled with HA/CS-EP showed significant increases in the number of osteoblasts and the bone formation area, and the areas of new bone formation in the HA/CS-EP group after 4 or 12 weeks' implantation reached 33% and 87%, respectively. The novel repair system of HA/CS-EP can induce bone formation, increase osteoblast quantity and improve osteogenesis, for EP can significantly promote the proliferation and activity of osteoblasts in the early stage and accelerate bone remodeling in the later stage. Composites containing EP could be a promising material with multifunctions of osteoinduction, osteoconduction and medication for bone repair, and herb medicine EP could be used as an osteoinduction material for bone tissue engineering.

Inflammatory pseudotumor of the spleen: A case report and review of published cases

Inflammatory pseudotumor of the spleen (IPTS) is an extremely rare condition. To the best of our knowledge, only ∼113 cases have been reported in the literature since the first 2 cases were reported in 1984. The present study reports the case of an IPTS in a 72-year-old male patient. The splenic tumor was identified incidentally 1 year prior to the patient being admitted to the Second Affiliated Hospital of Dalian Medical University (Dailan, China). There were no specific clinical symptoms. The initial diagnosis was of splenic lymphoma based on the pre-operative radiological findings. However, the patient underwent a splenectomy and the final pathological diagnosis of IPTS was declared. The present study also highlighted the difficulty of forming accurate pre-operative diagnoses, even when using modern imaging techniques. A partial resection of the spleen or splenectomy was considered to be the required treatment to form a definitive diagnosis and exclude malignancy. The prognosis of IPTS is generally considered to be favorable following splenectomy. The clinical and pathological features of previously reported cases are also briefly reviewed in the present study to aid in improving the accuracy of the diagnosis of this rare disease.

Overexpression of Gli1 in cancer interstitial tissues predicts early relapse after radical operation of breast cancer

OBJECTIVE

To investigate whether Gli1 expression is important in relapse after radical operation of breast cancer.

METHODS

Using immunohistochemistry, Gli1 expression was analyzed in human primary breast cancer (n=284) and paracancerous tissues (n=20), and also in local lymph nodes (n=28) and metastatic lymph nodes (n=28).

RESULTS

Initial analysis of Gli1 expression in a small cohort of 20 breast tumors and their paracancerous tissues showed a tendency towards Gli1 overexpression in breast cancer tissues (P<0.001). Further, Gli1 expression in 284 breast cancer tissue samples was analyzed and a significant correlation was found between increased expression of nuclear Gli1 and unfavorable recurrence-free survival (RFS) (P<0.05). The nuclear expression of Gli1 in metastatic lymph nodes following relapse after radical operation was much higher than that in the local lymph nodes of primary carcinoma (P<0.05). Most interestingly, the expression of Gli1 was much higher in the interstitial tissues of the relapsed group than of the non-relapsed group (P<0.001).

CONCLUSIONS

Breast cancer shows a high prevalence of Gli1 expression, which is significantly correlated with aggressive features and unfavorable RFS. Nuclear Gli1 overexpression, especially in the interstitial tissues, signified early relapse after radical operation of breast cancer.

MG132 alleviates liver injury induced by intestinal ischemia/reperfusion in rats: involvement of the AhR and NFκB pathways

BACKGROUND

MG132 is a potent antioxidant and has been reported to play a protective role in ischemia/reperfusion (I/R) of many organs. Recent studies have shown that the Aryl hydrocarbon receptor (AhR) may play a beneficial role in I/R of many organs and an AhR agonist has been implicated in an anti-inflammatory role. MG132 might function as an AhR agonist through proteasome inhibition, possibly through the inhibition of NFκB. Herein, we hypothesized that MG132 may play a protective role in liver injury induced by intestinal I/R and we analyzed the expression behavior of AhR and NFκB to determine whether the two factors play a role in intestinal I/R.

MATERIALS AND METHODS

Thirty-two Sprague-Dawley rats were divided into four groups: control, I/R, MG132 control, and MG132 pretreatment. The I/R and MG132 pretreatment groups were subjected to mesenteric arterial ischemia for 1 h and reperfusion for 3 h. The control and MG132 control groups underwent surgical preparation including isolation of the superior mesenteric artery (SMA) without occlusion. The MG132 control and MG132 pretreatment groups were subjected to intraperitoneal administration of 0.5 mg/kg MG132 30 min before surgery. We collected serum specimens to measure TNF-α, IL-6, liver tissue levels of malondialdehyde (MDA), AhR, and cyp1a2; NFκB, IκBα, and ICAM-1 were also tested. Histologic changes of liver and intestine were subsequently evaluated.

RESULTS

Compared with the control group, significant increases in MDA, NFκB, and ICAM-1 levels were accompanied by decreases in AhR, cyp1a2, and IκBα expression in the liver in the I/R group, which is consistent with liver and intestinal tissue injury. MG132 blocked the alterations of the indicators above. There were no changes in the MG132 control group compared with the control group in the indicators above.

CONCLUSIONS

This study demonstrated that MG132 has a significant effect in protection against liver injury induced by intestinal I/R, which may be due to modulation of the AhR and NFκB pathways.

Protein kinase B (akt) promotes pathological angiogenesis in murine model of oxygen-induced retinopathy

Akt, or protein kinase B, is an important signaling molecule that modulates many cellular processes such as cell growth, survival, and metabolism. However, the vivo roles and effectors of Akt in retinal angiogenesis are not explicitly clear. We therefore detected the expression of Akt using Western blotting or RT-PCR technologies in an animal model of oxygen-induced retinopathy, and investigated the effects of recombinant Akt on inhibiting vessels loss and Akt inhibitor on suppressing experimental retinal neovascularization in this model. We showed that in the hyperoxic phase of oxygen-induced retinopathy, the expression of Akt was greatly suppressed. In the hypoxic phase, the expression of Akt was increased dramatically. No significant differences were found in normoxic groups. Compared with control groups, administration of the recombinant Akt in the first phase of retinopathy markedly reduced capillary-free areas, while the administration of the Akt inhibitor in the second phase of retinopathy significantly decreased retinal neovascularization but capillary-free areas. These results indicate that Akt play a critical role in the pathological process (vessels loss and neovascularization) of mouse model of oxygen-induced retinopathy, which may provide a valubale therapeutic tool for ischemic-induced retinal diseases.

Netrin-1 overexpression in oxygen-induced retinopathy correlates with breakdown of the blood-retina barrier and retinal neovascularization

PURPOSES

Recent research has shown netrin-1 to promote neovascularization. We evaluate the expression of netrin-1 during retinal neovascularization in a murine model of oxygen-induced retinopathy.

METHODS

C57BL/6J mice were exposed to 75 ± 5% oxygen for 5 days and returned to room air to induce retinal neovascularization. Retinal neovascularization was observed by fluorescence angiography and was quantified by counting the endothelial nuclei protruding into the vitreous cavity after hematoxylin-eosin staining. RT-PCR and Western blot analyses were used to determine retinal netrin-1 mRNA and protein levels at postnatal days (PN) 13, 15 and 17.

RESULTS

In fluorescence angiograms, irregular neovascularization and fluorescein leakage were observed surrounding the unperfused areas in the hypoxic group. The hypoxic group had, on average, 50.70 ± 4.56 neovascular nuclei protruding into the vitreous body, while similar nuclei were absent in the control group. Compared to the normoxic group, there were significant increases in both retinal netrin-1 mRNA and protein levels in the hypoxic group at PN13, PN15 and PN17.

CONCLUSION

The netrin-1 level increases in murine retina under hypoxia and may be key in inducing retinal neovascularization.

Role of unc5b in retinal neovascularization in mice with oxygen-induced retinopathy

AIM

To explore the role of unc5b in retinal neovascularization in murine oxygen-induced retinopathy (OIR).

METHODS

On postnatal 7(P7), C57BL/6J mice were exposed to 75%±2% oxygen for 5 days. On postnatal 12(P12), the mice were brought back to the room air (21% oxygen) to induce retinal neovascularization. Western blot analysis was performed to examine the temporal expression of unc5b in murine retinas. Double staining for unc5b and isolectin B4 were employed to determine the location of unc5b in murine retinas. The effect of unc5b on retinal neovascularization was evaluated by intravitreal injection of unc5b-FC in mice with OIR. Retinal neovascularization was measured by counting neovascular cell nuclei above the internal limiting membrane and by angiography of flat-mounted retinas perfused with fluorescein dextran.

RESULTS

Compared to age-matched normal mice, the expression of unc5b was significantly increased in retinas of OIR mice on P17 and P21. Unc5b was apparently expressed in retinal vessels of OIR while being negative in normal retinal vessels. Retinal neovascularization in eyes injected with unc5b-FC was significantly reduced.

CONCLUSION

Unc5b-FC can effectively inhibit retinal neovascularization induced by OIR. It may serve as a powerful and novel therapy for ischemia-induced retinal disease.

[Effects of Gastric bypass surgery on the apoptosis of islet β-cells in type 2 nonobese diabetic (NOD) rats and its mechanism]

OBJECTIVE

To investigate the effects of Gastric bypass surgery on the apoptosis of islet β-cells in type 2 nonobese diabetic (NOD) rats and its mechanisms.

METHODS

Seventy-two 8-week-old GK rats were randomly divided into four groups:operation group (group O, n = 18), sham operation group (group S, n = 18), diet control group (group F, n = 18) and control group (group C, n = 18). The levels of fasting, postprandial blood glucose, insulin and glucagon-like peptide-1 (GLP-1) were measured and compared among the 4 groups before the operation and at 1, 2, 4 and 8 weeks following the operation. The blood samples were collected at 2, 4 and 8 weeks after the operation for the measurement of postprandial blood glucose, and then the rats in batches (6 rats in each group) were decapitated to retrieve the pancreas. The apoptosis of the islet β-cells was detected by using TUNEL assay, and the expression of apoptosis-related proteins Bcl-2, Bax was measured with immunohistochemistry.

RESULTS

As for group O, the fasting blood glucose level decreased from (16.2 ± 0.8) mmol/L before the operation to respectively (9.2 ± 0.6) mmol/L and (9.7 ± 0.7) mmol/L at 4 and 8 weeks after the operation; postprandial blood glucose decreased from (31.1 ± 1.1) mmol/L before the operation to respectively (13.1 ± 0.7) mmol/L and (12.3 ± 0.7) mmol/L at 4 and 8 weeks after the operation. Fasting insulin level increased from (28.0 ± 1.2) mU/L before the operation to respectively (62.8 ± 1.9) mU/L and (61.7 ± 1.4) mU/L at 4 and 8 weeks after the operation; and at 4 and 8 weeks after the operation postprandial insulin level was (77.4 ± 1.1) mU/L and (77.1 ± 1.0) mU/L. At 2 weeks from the operation, the fasting GLP-1 in group O increased from (10.7 ± 1.0) pmol/L to (13.5 ± 0.8) pmol/L, and respectively to (26.1 ± 0.9) pmol/L and (25.3 ± 1.2) pmol/L at 4 and 8 weeks after the operation. The differences in the above-mentioned items before and after the operation were all significant in group O (P < 0.05), and the differences in the items among group O and the other three groups (P < 0.05) were all significant as well. In group O, the apoptosis rate of pancreatic islet cell decreased to (5.9 ± 0.7)% at 4 weeks from the operation, and (6.3 ± 1.1)% at 8 weeks from the operation (P < 0.05). The expression of Bcl-2 protein in group O was 31.3 ± 1.5, 35.7 ± 1.0 and 35.8 ± 0.8 at 2, 4 and 8 weeks post operation, which was significantly higher in statistics than those of the same time point in the other three groups (P < 0.05). The expression of Bax protein in group O was 13.3 ± 0.9, 10.8 ± 0.9 and 10.9 ± 1.1 at 2, 4 and 8 weeks from the operation, which was significantly lower in statistics than those of the same time point in the other three groups (P < 0.05).

CONCLUSIONS

Gastric bypass surgery can significantly reduce the blood glucose level and promote the secretion of GLP-1, and therefore inhibit the apoptosis of the islet β cells in diabetic rats through the Bcl-2 pathway.

Sulforaphane protects liver injury induced by intestinal ischemia reperfusion through Nrf2-ARE pathway

AIM: To investigate the effect of sulforaphane (SFN) on regulation of NF-E2-related factor-2 (Nrf2)-antioxidant response element (ARE) pathway in liver injury induced by intestinal ischemia/reperfusion (I/R).

METHODS: Rats were divided randomly into four experimental groups: control, SFN control, intestinal I/R and SFN pretreatment groups (n = 8 in each group). The intestinal I/R model was established by clamping the superior mesenteric artery for 1 h and 2 h reperfusion. In the SFN pretreatment group, surgery was performed as in the intestinal I/R group, with intraperitoneal administration of 3 mg/kg SFN 1 h before the operation. Intestine and liver histology was investigated. Serum levels of aspartate aminotransferase (AST), and alanine aminotransferase (ALT) were measured. Liver tissue superoxide dismutase (SOD), myeloperoxidase (MPO), glutathione (GSH) and glutathione peroxidase (GSH-Px) activity were assayed. The liver transcription factor Nrf2 and heme oxygenase-1 (HO-1) were determined by immunohistochemical analysis and Western blotting analysis.

RESULTS: Intestinal I/R induced intestinal and liver injury, characterized by histological changes as well as a significant increase in serum AST and ALT levels (AST: 260.13 ± 40.17 U/L vs 186.00 ± 24.21 U/L, P < 0.01; ALT: 139.63 ± 11.35 U/L vs 48.38 ± 10.73 U/L, P < 0.01), all of which were reduced by pretreatment with SFN, respectively (AST: 260.13 ± 40.17 U/L vs 216.63 ± 22.65 U/L, P < 0.05; ALT: 139.63 ± 11.35 U/L vs 97.63 ± 15.56 U/L, P < 0.01). The activity of SOD in the liver tissue decreased after intestinal I/R (P < 0.01), which was enhanced by SFN pretreatment (P < 0.05). In addition, compared with the control group, SFN markedly reduced liver tissue MPO activity (P < 0.05) and elevated liver tissue GSH and GSH-Px activity (P < 0.05, P < 0.05), which was in parallel with the increased level of liver Nrf2 and HO-1 expression.

CONCLUSION: SFN pretreatment attenuates liver injury induced by intestinal I/R in rats, attributable to the antioxidant effect through Nrf2-ARE pathway.

Prophylaxis with carnosol attenuates liver injury induced by intestinal ischemia/reperfusion

AIM: To investigate the possible protective effects of carnosol on liver injury induced by intestinal ischemia reperfusion (I/R).

METHODS: Rats were divided randomly into three experimental groups: sham, intestinal I/R and carnosol treatment (n = 18 each). The intestinal I/R model was established by clamping the superior mesenteric artery for 1 h. In the carnosol treatment group, surgery was performed as in the intestinal I/R group, with intraperitoneal administration of 3 mg/kg carnosol 1 h before the operation. At 2, 4 and 6 h after reperfusion, rats were killed and blood, intestine and liver tissue samples were obtained. Intestine and liver histology was investigated. Serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and interleukin (IL)-6 were measured. Liver tissue superoxide dismutase (SOD) and myeloperoxidase (MPO) activity were assayed. The liver intercellular adhesion molecule-1 (ICAM-1) and nuclear factor κB (NF-κB) were determined by immunohistochemical analysis and western blot analysis.

RESULTS: Intestinal I/R induced intestine and liver injury, characterized by histological changes, as well as a significant increase in serum AST and ALT levels. The activity of SOD in the liver tissue decreased after I/R, which was enhanced by carnosol pretreatment. In addition, compared with the control group, carnosol markedly reduced liver tissue MPO activity and serum IL-6 level, which was in parallel with the decreased level of liver ICAM-1 and NF-κB expression.

CONCLUSION: Our results indicate that carnosol pretreatment attenuates liver injury induced by intestinal I/R, attributable to the antioxidant effect and inhibition of the NF-κB pathway.

Proteasome inhibitor lactacystin ablates liver injury induced by intestinal ischaemia-reperfusion

1. The aim of the present study was to investigate the role of proteasome in the pathogenesis of liver injury induced by intestinal ischaemia-reperfusion (I/R) and the effect of the proteasome inhibitor lactacystin on neutrophil infiltration, intracellular adhesion molecule (ICAM)-1 and nuclear factor (NF)-kappaB expression in the liver tissues of rats. 2. Thirty-two Wistar rats were randomly divided into four groups (n = 8 in each group) as follows: (i) a control, sham-operated group; (ii) an I/R group subjected to 1 h intestinal ischaemia and 4 h reperfusion; (iii) a group pretreated with 0.2 mg/kg lactacystin 1 h before intestinal I/R; and (iv) a group pretreated with 0.6 mg/kg lactacystin 1 h before intestinal I/R. Liver and intestine histology were observed. Serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH), as well as 20S proteasome activity in circulating white blood cells, were measured. Myeloperoxidase (MPO) activity in liver tissues and the immunohistochemical expression of liver NF-kappaB and ICAM-1 were assayed. In addition, a western blot of liver NF-kappaB was performed. 3. Compared with the sham-operated control group, liver and intestine injury was induced by intestinal I/R, characterized as histological damage including oedema, haemorrhage and infiltration by inflammatory cells, as well as a significant increase in serum AST (365 +/- 121 vs 546 +/- 297 IU/L, respectively; P < 0.05), ALT (65 +/- 23 vs 175 +/- 54 IU/L, respectively; P < 0.01) and LDH levels (733 +/- 383 vs 1434 +/- 890 IU/L, respectively; P < 0.05). Compared with the control group, MPO activity in the liver tissues increased significantly in the I/R group (2.05 +/- 0.69 vs 3.42 +/- 1.11 U/g, respectively; P < 0.05). Strong positive expression of liver ICAM-1 and NF-kappaB p65 was observed. 4. Compared with the intestinal I/R group, administration of 0.6 mg/kg lactacystin markedly reduced 20S proteasome activity in circulating white blood cells (15.47 +/- 4.00 vs 2.07 +/- 2.00 pmol 7-amino-4-methylcoumarin (AMC)/s per mg, respectively; P < 0.01) and ameliorated liver injury, which was demonstrated by decreased levels of serum AST (546 +/- 297 vs 367 +/- 86 IU/L, respectively; P < 0.05), ALT (175 +/- 54 vs 135 +/- 26 IU/L, respectively; P < 0.05) and LDH (1434 +/- 890 vs 742 +/- 218 IU/L, respectively; P < 0.05) and a reduced liver pathological score (2.13 +/- 0.64 vs 1.25 +/- 0.46, respectively; P < 0.01). Compared with the intestinal I/R group, MPO activity in liver tissues decreased significantly following lactacystin pretreatment (3.42 +/- 1.11 vs 2.58 +/- 0.61 U/g, respectively; P < 0.05) and the expression of liver NF-kappaB and ICAM-1 was markedly ameliorated. 5. The present study reveals that the proteasome inhibitor lactacystin ablates liver injury induced by intestinal I/R. One possible mechanism responsible for this effect is the inhibition of enhanced ICAM-1 and neutrophil infiltration by inhibition of NF-kappaB activity. The results suggest the feasibility of using proteasome inhibitor clinically in the treatment of intestinal I/R.

Protection of Veratrum nigrum L. var. ussuriense Nakai alkaloids against ischemia-reperfusion injury of the rat liver

AIM: To investigate the protective effects and possible mechanisms of Veratrum nigrum L.var. ussuriense Nakai alkaloids (VnA) on hepatic ischemia/reperfusion (I/R) injury in rats.

METHODS: Forty male Wistar rats were randomly divided into four experimental groups (n = 10 in each): (A) Control group (the sham operation group); (B) I/R group (pretreated with normal saline); (C) Small-dose (10 μg/kg) VnA pretreatment group; (D) Large-dose (20 μg/kg) VnA pretreatment group. Hepatic ischemia/reperfusion (Hepatic I/R) was induced by occlusion of the portal vein and the hepatic artery for 90 min, followed by reperfusion for 240 min. The pretreatment groups were administered with VnA intraperitoneally, 30 min before surgery, while the control group and I/R group were given equal volumes of normal saline. Superoxide dismutase (SOD) activity, myeloperoxidase (MPO) activity and nitric oxide (NO) content in the liver tissue at the end of reperfusion were determined and liver function was measured. The expression of intercellular adhesion molecule-1 (ICAM-1) and E-selectin (ES) were detected by immunohistochemical examinations and Western blot analyses.

RESULTS: The results showed that hepatic I/R elicited a significant increase in the plasma levels of alanine aminotransferase (ALT: 74.53 ± 2.58 IU/L vs 1512.54 ± 200.76 IU/L, P < 0.01) and lactic dehydrogenase (LDH: 473.48 ± 52.17 IU/L vs 5821.53 ± 163.69 IU/L, P < 0.01), as well as the levels of MPO (1.97 ± 0.11 U/g vs 2.57 ± 0.13 U/g, P < 0.01) and NO (69.37 ± 1.52 μmol/g protein vs 78.39 ± 2.28 μmol/g protein, P < 0.01) in the liver tissue, all of which were reduced by pretreatment with VnA, respectively (ALT: 1512.54 ± 200.76 IU/L vs 977.93 ± 89.62 IU/L, 909.81 ± 132.76 IU/L, P < 0.01, P < 0.01; LDH: 5821.53 ± 163.69 IU/L vs 3015.44 ± 253.01 IU/L, 2448.75 ± 169.4 IU/L, P < 0.01, P < 0.01; MPO: 2.57 ± 0.13 U/g vs 2.13 ± 0.13 U/g, 2.07 ± 0.05 U/g, P < 0.01, P < 0.01; NO: 78.39 ± 2.28 μmol/g protein vs 71.11 ± 1.73 μmol/g protein, 68.58 ± 1.95 μmol/g protein, P < 0.05, P < 0.01). The activity of SOD (361.75 ± 16.22 U/mg protein vs 263.19 ± 12.10 U/mg protein, P < 0.01) in the liver tissue was decreased after I/R, which was enhanced by VnA pretreatment (263.19 ± 12.10 U/mg protein vs 299.40 ± 10.80 U/mg protein, 302.09 ± 14.80 U/mg protein, P < 0.05, P < 0.05). Simultaneously, the histological evidence of liver hemorrhage, polymorphonuclear neutrophil infiltration and the overexpression of ICAM-1 and E-selectin in the liver tissue were observed, all of which were attenuated in the VnA pretreated groups.

CONCLUSION: The results demonstrate that VnA pretreatment exerts significant protection against hepatic I/R injury in rats. The protective effects are possibly associated with enhancement of antioxidant capacity, reduction of inflammatory responses and suppressed expression of ICAM-1 and E-selectin.

Proteasome inhibition attenuates lung injury induced by intestinal ischemia reperfusion in rats

The aim of this study is to investigate the role of proteasome in the pathogenesis of lung injury induced by intestinal ischemia/reperfusion (I/R) by examining the effect of the proteasome inhibitor lactacystin on neutrophil infiltration, intracellular adhesion molecule-1 (ICAM-1) expression and nuclear factor kappa B (NF-kappaB) activation. Thirty-two Wistar rats were divided into (1) control, (2) intestinal I/R, (3) 0.2 mg/kg lactacystin pretreated, and (4) 0.6 mg/kg lactacystin pretreated groups (n=8). Injuries in lung and intestine were induced by intestinal I/R, and were characterized by histological edema, hemorrhage and infiltration of inflammatory cells. The results showed a significant increase in serum creatine kinase B (CK-B) and lung water content in intestine and lung injuries. As compared with the control group, the myeloperoxidase (MPO) activity in intestine and lung as well as the serum TNF-alpha level increased significantly in intestinal I/R group. Simultaneously, expression of ICAM-1 and NF-kappaB p65 was also observed in the I/R group. Pre-treatment with lactacystin markedly reduced 20S proteasome activity in circulating white blood cells and ameliorated intestine and lung injuries. These results demonstrated that the proteasome participates in the pathogenesis of lung injury induced by intestinal I/R. Lactacystin as a proteasome inhibitor can prevent this kind of injury by decreasing ICAM-1 and TNF-alpha production via the inhibition of NF-kappaB activation.

Effect of nuclear factor-kB on P-selectin expression and neutrophil infiltration in liver injury induced by intestinal ischemia/reperfusion in rats

AIM: To investigate the effect of nuclear factor-κB (NF-κB) on P-selectin expression and neutro-phil accumulation in liver injury induced by intestinal ischemia/reperfusion (I/R) in rats.

METHODS: Twenty-four Wistar rats were randomly assigned into sham operation (control, n = 8), intestinal I/R (n= 8), and pyrrolidine dithiocarbamate (PDTC) treatment (n = 8). The rats in I/R and PDTC group received 1 h SMA occlusion and 2 h reperfusion, and those in PDTC group was also intraperitoneally injected with 20 g/L PDTC (100 mg/kg) 1 h before operation. Liver histology was observed under light microscope. The level of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and interleukin-6 (IL-6), and liver tissue superoxide dismutase (SOD), myeloperoxidase (MPO) contents were measured. The immunohistochemical expression of liver NF-κB and P-selectin as well as Western blot analysis of liver NF-κB were assayed.

RESULTS: Liver injury was induced by intestinal I/R, characterized as histological damage of edema, hemorrhage and polymorphonuclear infiltration as well as the significant rise of serum ALT (from 143.16 ± 53.02 to 192.31 ± 42.09 U/L, P < 0.05) and AST level (from 387.46 ± 78.74 to 507.56 ± 96.26 U/L, P < 0.01). In comparison with that in control group, the level of serum IL-6 increased significantly (from 22.51 ± 6.10 to 42.85 ± 7.35 ng/L, P < 0.01) in I/R group, and tissue SOD decreased (from 244.87 ± 25.11 to 173.21 ± 16.60 U/mgprot, P < 0.01) while MPO increased (from 2.36 ± 0.56 to 4.32 ± 0.77 U/g, P < 0.01) significantly. Strong positive expression of NF-κB p65 and P-selectin were observed. After PDTC administration, the level of serum IL-6, tissue SOD and MPO were improved markedly (28.08 ± 7.55 ng/L, P < 0.05; 253.45 ± 25.21 U/mgprot, P < 0.01; 3.58 ± 0.49 U/g, P < 0.05) as compared with those in I/R group, and the expression of NF-κB and P-selectin were weakened markedly.

CONCLUSION: The activation of NF-κB plays an important role in the pathogenesis of liver injury induced by intestinal through up-regulating the neutrophil infiltration and liver P-selectin expression. PDTC as an inhibitor of NF-κB can prevent this injury through inhibiting NF-κB activity.

Protective effect of pyrrolidine dithiocarbamate on liver injury induced by intestinal ischemia-reperfusion in rats

BACKGROUND

The nuclear translocation of transcription factors may be a critical factor in the intracellular pathway involved in ischemia/reperfusion (I/R) injury. The aim of the study was to evaluate the role of nuclear factor-kappa B (NF-kappaB) in the pathogenesis of liver injury induced by intestinal ischemia/reperfusion (IIR) and to investigate the effect of pyrrolidine dithiocarbamate (PDTC) on this liver injury.

METHODS

Male Wistar rats were divided randomly into three experimental groups (8 rats in each): sham operation group (control group); intestinal/reperfusion group (I/R group): animals received 1-hour of intestinal ischemia and 2-hour reperfusion; and PDTC treatment group (PDTC group): animals that received I/R subject to PDTC treatment (100 mg/kg). The histological changes in the liver and intestine were observed, and the serum levels of tumor necrosis factor-alpha (TNF-alpha), alanine aminotransferase (ALT), aspartate aminotransferase (AST), liver superoxide dismutase (SOD), and nitrite/nitrate (NO) were measured. The immunohistochemical expression and Western blot analysis of liver NF-kappaB and intercellular adhesion molecule-1 (ICAM-1) were observed.

RESULTS

IIR induced liver injury characterized by the histological changes of liver edema, hemorrhage, polymorphonuclear neutrophil (PMN) infiltration, and elevated serum levels of AST and ALT. The serum TNF-alpha level was significantly higher than that of the control group (P<0.01) and a high level of liver oxidant product was observed (P<0.01). These changes were parallel to the positive expression of NF-kappaB and ICAM-1. After the administration of PDTC, the histological changes after liver injury were improved; the levels of SOD and NO in the liver were elevated and reduced, respectively (P<0.01). The expressions of ICAM-1 and NF-kappaB in the liver were weakened (P<0.01).

CONCLUSION

NF-kappaB plays an important role in the pathogenesis of liver injury induced by IIR. PDTC, an agent known to inhibit the activation of NF-kappaB, can reduce and prevent this injury.

Effect of nuclear factor kappa B on intercellular adhesion molecule-1 expression and neutrophil infiltration in lung injury induced by intestinal ischemia/reperfusion in rats

AIM: To investigate the role of nuclear factor kappa B (NF-κB) in the pathogenesis of lung injury induced by intestinal ischemia/reperfusion (I/R), and its effect on intercellular adhesion molecule-1 (ICAM-1) expression and neutrophil infiltration.

METHODS: Twenty-four Wistar rats were divided randomly into control, I/R and pyrrolidine dithiocarbamate (PDTC) treatment groups, n = 8 in each. I/R group and PDTC treatment group received superior mysenteric artery (SMA) occluding for 1 h and reperfusion for 2 h. PDTC group was administrated with intraperitoneal injection of 2% 100 mg/kg PDTC 1 h before surgery. Lung histology and bronchia alveolus lung fluid (BALF) protein were assayed. Serum IL-6, lung malondialdehyde (MDA) and myeloperoxidase (MPO) as well as the expression level of NF-κB and ICAM-1 were measured.

RESULTS: Lung injury induced by intestinal I/R, was characterized by edema, hemorrhage and neutrophil infiltration as well as by the significant rising of BALF protein. Compared to control group, the levels of serum IL-6 and lung MDA and MPO increased significantly in I/R group (P = 0.001). Strong positive expression of NF-κB p65 and ICAM-1 was observed. After the administration of PDTC, the level of serum IL-6, lung MDA and MPO as well as NF-κB and ICAM-1 decreased significantly (P < 0.05) when compared to I/R group.

CONCLUSION: The activation of NF-κB plays an important role in the pathogenesis of lung injury induced by intestinal I/R through upregulating the neutrophil infiltration and lung ICAM-1 expression. PDTC as an inhibitor of NF-κB can prevent lung injury induced by intestinal I/R through inhibiting the activity of NF-κB.

Expression and role of inducible nitric oxide synthase in ischemia-reperfusion liver in rats

OBJECTIVE

To investigate the expression and the role of iNOS expression in hepatic ischemia-reperfusion (I/R) injury.

METHODS

Male Wistar rats were subjected to 30-minute hepatic ischemia, then iNOS protein and iNOS mRNA expression in liver tissue was assessed by Western blot and RT-PCR analysis respectively at different time points after reperfusion. The effects of L-NAME (Nomega-nitro-L-arginine methyl ester, a nonselective NOS inhibitor) or AE-ITU (aminoethytl-isothiourea, a relative selective inhibitor of iNOS) treatment were also evaluated.

RESULTS

High levels of iNOS protein and mRNA expression were detected in the liver tissue subjected to I/R, but not in the sham-operated rats. iNOS protein and iNOS mRNA expression reached a maximum on the first day after reperfusion and decreased later. The levels of iNOS protein and iNOS mRNA disappeared on 7th, 3rd day after reperfusion respectively. The high iNOS expression was correlated with hepatic dysfunction. L-NAME administration worsened hepatic dysfunction induced by hepatic I/R. In contrast, AE-ITU administration showed mild protective effects against hepatic dysfunction induced by hepatic I/R.

CONCLUSION

Ischemia-reperfusion may induce or up-regulate the expression of iNOS protein and iNOS mRNA, which is detrimental to hepatic I/R injury

Novel microbial hydroxylation of 13-ethyl-17 beta-hydroxy-18,19-dinor-17 alpha-pregn-4-en-20-yn-3-one

The microbial transformation of the dl and the d-enantiomer of 13-ethyl-17 beta-hydroxy-18,19-dinor-17 alpha-pregn-4-en-20-yn-3-one (1) were investigated. Poor yields and poor resolutions were usually obtained for the hydroxylation reactions. Transformation of 1 by Cunninghamella blakesleeana gave 6 beta-, 7 beta-, 10 beta-, 15 alpha-hydroxy derivatives 4, 5, 6, 7, and 6 beta,10 beta-dihydroxy derivative 8; transformation of 1 by Cunninghamella echinulata afforded 5, 6, and 8. Biotransformation of dl-1 by Cunninghamella species usually gave 10 beta-hydroxy product with the low enanitomeric excess or as the racemic form. However, C. echinulata was able to efficiently differentiate the two enantiomers of 1 in the course of 6 beta,10 beta-dihydroxylation reactions. The d-enantiomer of the dl-1 was the better substrate for this type hydroxylation. The 7 beta and 15 alpha-hydroxylations of 1 by microbial cultures was unusual for 19-nor type steroids, and these hydroxylation reactions were presumably due to the presence of 17 alpha-ethynyl group.

Conditioned medium from activated microglia promotes cholinergic differentiation in the basal forebrain in vitro

In earlier studies we found that treatment with interferon-gamma (IFN-gamma) produced an 8- to 11-fold increase in choline acetyltransferase (ChAT) in cultured cells taken from Embryonic Day 16 (E16) septal nuclei with adjacent basal forebrain (SN/BF). Since younger cultures responded even more profoundly to IFN treatment, we have tested the possibility that the action of IFN (or its intermediate; see below) is to prompt the cholinergic differentiation of neuronal precursors. SN/BF cultures of various ages were labeled with a retrovirus engineered to express beta-galactosidase (Lac-Z), and ChAT-positive descendants of the retrovirally labeled precursors were counted. IFN-gamma treatment of cultures caused as much as an 8.8-fold increase in the proportion of ChAT-positive cells present in Lac-Z-positive clones, suggesting that IFN promoted cholinergic differentiation in precursor populations. By contrast, bFGF increased clone size but did not change the proportion of ChAT-positive cells. NGF affected neither. Only ameboid microglia present in the cultures responded to IFN with characteristic nuclear translocation of the signal transducing molecule p91, suggesting that a microglial-derived molecule may mediate the action of IFN. Consistent with this hypothesis, conditioned media from cultures of enriched, activated microglia also increased ChAT activity in a dose-dependent fashion. Conditioned media from an unstimulated macrophage/monocyte cell line (RAW 264.7) also proved extremely efficacious in raising ChAT activity. In addition, conditioned media from both activated microglia and RAW 264.7 cells increased the proportion of ChAT-positive cells in retrovirally labeled clones to the same extent as IFN itself, suggesting the possibility that they contain the molecule(s) that mediates the action of IFN. Preliminary characterization of this molecule suggests that it is a very stable and large protein. Together these data suggest that a molecule promoting cholinergic differentiation is produced by activated microglia and other macrophage-like cells. The identity of this molecule and its precise role in normal development await its further purification.

Microbial hydroxylation of 13-ethyl-17 beta-hydroxy-18,19-dinor-17 alpha-pregn-4-en-20-yn-3-one

The microbial transformation of the racemic mixture of 13-ethyl-17 beta-hydroxy-18,19-dinor-17 alpha-pregn-4-en-20-yn-3-one (1) was investigated. Rhizopus nigricans (AS 3.2050), R. arrhizus (AS 3.4523), Aspergillus niger (AS 3.2744), A. ochraceus (AS 3.1408), and Curvularia lunata (NRRL 4381) transformed 1 into its 10 beta-hydroxy derivative (2) as a major metabolite. Biotransformation of 1 by Aspergillus ochraceus AS 3.1408 afforded 7 beta-hydroxy derivative (3) as the only product.