Tanshinone IIA attenuates peritoneal fibrosis through inhibition of fibrogenic growth factors expression in peritoneum in a peritoneal dialysis rat model

BACKGROUND

Peritoneal fibrosis is a common complication of long-term peritoneal dialysis (PD) and is the main cause of dialysis inadequacy and PD withdrawal. It has been reported that Tanshinone IIA can ameliorate fibrosis in various tissues. In this report, we investigate the effects of Tanshinone IIA on peritoneal fibrosis in an animal model.

METHODS

Forty rats were randomly divided into four groups (n = 10 per group) that received daily intraperitoneal injection of saline, 4.25% glucose-based peritoneal dialysis fluid (PDF), or PDF along with 50 or 100 mg/L Tanshinone IIA. Eight weeks later, the rats were sacrificed and peritoneal tissue samples were collected for analysis. The expression of transforming growth factor-β1 (TGF-β1) and connective tissue growth factor (CTGF) in parietal peritoneum was examined by immunohistochemistry. The mRNA and protein expression of TGF-β1 and CTGF in omentum was examined by reverse transcription polymerase chain reaction or Western blot.

RESULTS

Tanshinone IIA significantly suppressed submesothelial compact zone thickening and matrix accumulation induced by 4.25% glucose-based PDF. Tanshinone IIA also reduced TGF-β1 and CTGF expression in parietal peritoneum as well as in omentum in a dose-dependent manner.

CONCLUSION

Tanshinone IIA prevented the progression of peritoneal fibrosis in this rat model. Tanshinone IIA may be a novel therapy for peritoneal fibrosis in patients undergoing long-term PD.

Salivary gland gene expression atlas identifies a new regulator of branching morphogenesis

During organ development, local changes in gene expression govern morphogenesis and cell fate. We have generated a microanatomical atlas of epithelial gene expression of embryonic salivary glands. The mouse submandibular salivary gland first appears as a single mass of epithelial cells surrounded by mesenchyme, and it undergoes rapid branching morphogenesis to form a complex secretory organ with acini connected to an extensive ductal system. Using laser capture microdissection, we collected samples from 14 distinct epithelial locations at embryonic days 12.5, 13.5, 14, and 15, and characterized their gene expression by microarray analysis. These microarray results were evaluated by qPCR of biological replicates and by comparisons of the gene expression dataset with published expression data. Using this gene expression atlas to search for novel regulators of branching morphogenesis, we found a substantial reduction in mRNA levels of GSK3β at the base of forming clefts. This unexpected finding was confirmed by immunostaining, and inhibition of GSK3β activity enhanced salivary gland branching. This first microanatomical expression atlas of a developing gland characterizes changes in local gene expression during salivary gland development and differentiation, which should facilitate the identification of key genes involved in tissue morphogenesis.

Involvement of peroxinectin in the defence of red swamp crayfish Procambarus clarkii against pathogenic Aeromonas hydrophila

Cell adhesion factors are important immune components for invertebrate to immobilize, phagocytose or encapsulate invasive microorganisms and foreign particles. In this study, a new cell adhesion factor, peroxinectin (refered as Pcpxin) was isolated from hemocytes of red swamp crayfish (Procambarus clarkii). The full-length cDNA of Pcpxin was 3014 bp encoding a protein of 819 amino acid residues with a predicted molecular weight of 89.0 kDa and a calculational isoelectric point of 6.93. The putative amino acid sequence contained a peroxidase domain and a signal peptide of 21 amino acid residues, and exhibited high identity to peroxinectin from Pacifastacus leniusculus (85%), Fenneropenaeus chinensis (62%) and Scylla serrata (58%), as well as peroxidase from Camponotus floridanus (40%), Pediculus humanus corporis (39%), and Culex quinquefasciatus (38%). Quantitative real time PCR revealed that mRNA expression of Pcpxin in hemocytes could be inhibited by challenge with heat-killed Aeromonas hydrophila, suggesting that Pcpxin was involved in immune responses to A. hydrophila. RNA interference (RNAi) experiment demonstrated that silencing Pcpxin significantly reduced the survival rate of red swamp crayfishes after challenge with A. hydrophila, which indicated that Pcpxin was important for P. clarkii to survive A. hydrophila infection. Moreover, silencing Pcpxin inhibited the up-regulation of crustin1 and lysozyme expression in response to challenge with heat-killed A. hydrophila. This result suggested that Pcpxin might participate in antibacterial peptide gene expression and thereby might be involved in signal transduction pathway regulating the expression of antibacterial peptide gene.

Genetic diversity of the major histocompatibility complex class II in Alaskan caribou herds

We have sampled five different herds of caribou in Alaska to ascertain their major histocompatibility complex (MHC) class II diversity, and to assess whether the herds were significantly different in their MHC class II allele profiles. We complemented the MHC results with data from nine neutral microsatellite markers. The results indicate that while the microsatellites are diverse, there are no significant differences between the herds. However, for the MHC, we have shown that there is diversity at three of the four loci studied, the different herds have significantly different MHC class II allele profiles. It is also clear that although some of the herds have overlapping ranges, they are still different for their MHC class II alleles.

Increased 18F-FDG uptake and expression of Glut1 in the EMT transformed breast cancer cells induced by TGF-beta

As carcinomas progress, the tumors may lose epithelial morphology and acquire mesenchymal characteristics typically called epithelial-mesenchymal transition (EMT), which is commonly associated with increased cell migration, enables cells to dissociate from their original tissue and form metastasis in distant organs. In addition to molecular and morphologic changes, the EMT transformed cells also showed the change of sensitivity to chemotherapeutics. In order to detect the EMT transition in vivo clinically, we detected the change of metabolism of MCF-7 cells after being induced by TGF-beta to form EMT condition by MTT and 18F-FDG uptake.

Protecting effects of a large dose of dexamethasone on spleen injury of rats with severe acute pancreatitis

BACKGROUND AND AIMS

To explore the protecting effects and mechanisms of dexamethasone on spleen injury in rats with severe acute pancreatitis (SAP).

METHODS

The rats were randomly divided into a model control group, treated group and sham-operated group. The contents of plasma endotoxin, serum NO, phospholipase A(2) enzyme (PLA(2)) and endothelin-1 (ET-1) were determined. The mortality rate, pathological changes and changes of Bax and Bcl-2 protein expression levels and apoptotic indexes in the spleen of rats were observed in all groups, respectively, at 3, 6 and 12 h after operation.

RESULTS

Although the survival rate was significantly higher in the treated group than in the model control group, there was no significantly different between them (P > 0.05). The expression levels of Bax and Bcl-2 proteins and apoptotic indexes were significantly higher in the treated group than in the model control group at different time points (P < 0.05 or P < 0.01) while other blood indexes contents and pathological severity scores of spleen were significantly lower in the treated group than in the model control group (P < 0.05, P < 0.01 or P < 0.001).

CONCLUSION

Dexamethasone can protect spleen from injury during SAP mainly by reducing the content of inflammatory mediators in blood.

Applying solubilization treatment to reverse clogging in laboratory-scale vertical flow constructed wetlands

Substrate clogging is characterized as a frequently occurring operational problem for subsurface-flow constructed wetlands. The application of solubilization treatment to reduce clogging was tested in lab-scaled setups to provide a promising solution. The performance of solubilization treatment on reducing clogging and the related effects on plants and biofilms in the wetland system were investigated in this paper. The results showed that the infiltration rate and available porosity of wetland substrate increased as a function of increased dosage of NaOH, HCl, NaClO, and detergent, respectively. Among the four solvents, it appeared that NaClO had the most obvious effects on reducing clogging and the infiltration rate and effective porosity recovered to 69% of the original condition. The two possible reasons for solubilization were the flocculents' structure of the clogs was broken up or parts of the organic clogs were dissolved. The function of adding NaOH and NaClO was to dissolve the protein and polysaccharides of the organic clogs; the function of adding HCl was to release the anaerobic gas wrapped in the organic clogs. Furthermore, experiments results also showed that the solubilized solvents did not demonstrate a long-term negative effect on plants and biofilms.