[Emodin ameliorates the peritoneal dialysis-related peritoneal fibrosis via inhibiting the activation of Notch pathway].

Long term peritoneal dialysis (PD) is often associated with peritoneal fibrosis. The aim of this study was to explore the effect of emodin on PD-related peritoneal fibrosis and its related cellular and molecular mechanism. PD-related peritoneal fibrosis rats and cultured rat peritoneal mesothelial cells were recruited in the experiment. PD-related peritoneal fibrosis was induced by intraperitoneal injection of lactate-buffered solution containing 4.25% glucose. The peritoneal equilibrium test (PET) was performed at the end of 2 weeks, 4 weeks, and 6 weeks, respectively. HE staining and Masson staining were used for histopathological evaluation. Enzyme linked immunosorbent assay (ELISA) was used to measure the plasma N-terminal procollagen III propeptide (PIIINP) level. Real-time PCR technique was used to detect the mRNA levels of Notch1, Jagged-1, and Hes-1 in peritoneal tissue. Western blot was applied to identify the protein levels of Notch1, Jagged-1, Hes-1, and Notch intracellular domain (NICD). In vitro, Notch1 overexpressing or knockdown rat peritoneal mesothelial cells were established and Western blot was used to examine the effect of emodin on the expressions of Hes-1 and Hey. Compared with the control group, HE staining revealed that PD rats suffered from decreasing in mesothelial cells, or detaching from surface of parietal peritoneum, accompanied by infiltration of inflammatory cells; Masson staining result showed thickened peritonea (P < 0.01), and the collagen deposition in the parietal peritoneum was increased; also, PIIINP level in plasma was elevated (P < 0.01). Treatment of the PD rats with emodin increased mesothelial cells in peritoneal tissue, and decreased the peritoneal thickness (P < 0.01), collagen depositions, as well as the plasma PIIINP level (P < 0.05). The expressions of Notch1, Jagged-1, Hes-1 and NICD in peritoneal tissue were also attenuated (P < 0.05 or P < 0.01). In cultured rat peritoneal mesothelial cells, compared with emodin group, emodin further inhibited the expressions of Hes-1 and Hey induced by Notch1-overexpression (P < 0.05), but not the expressions of Hes-1 and Hey induced by Notch1-knockdown (P > 0.05). Therefore, the activation of Notch pathway may be involved in the pathological process of PD-induced peritoneal fibrosis. Emodin may ameliorate the PD-related peritoneal fibrosis through inhibiting the activation of Notch pathway.

Oleaginous Microalgae from Dairy Farm Wastewater for Biodiesel Production: Isolation, Characterization and Mass Cultivation.

Producing biodiesel from microalgae grown in wastewater is environment-friendly and cost-effective. The present study investigated the algae found in wastewater of a local dairy farm for their potential as biodiesel feedstocks. Thirteen native algal strains were isolated. On the basis of morphology and 16S/18S rRNA gene sequences, one strain was identified to be a member of cyanobacteria, while other 12 strains belong to green algae. After screening, two Scenedesmus strains out of the 13 microalgae isolates demonstrated superiority in growth rate, lipid productivity, and sedimentation properties, and therefore were selected for further scale-up outdoor cultivation. Both Scenedesmus strains quickly adapted to the outdoor conditions, exhibiting reasonably good growth and strong anti-contamination capabilities. In flat-plate photobioreactors (PBRs), algal cells accumulated predominantly neutral lipids that accounted for over 60% of total lipids with almost 70% being triacylglycerol. In addition, Scenedesmus obliquus had a high content of monounsaturated fatty acids, of which the amount of oleic acid (C18:1) was up to 27.11%. Based on these findings, the dairy farm wastewater-isolated Scenedesmus strains represent promising sources of low-cost, high-quality oil for biofuel production.