Panax notoginseng transcription factor WRKY15 modulates resistance to Fusarium solani by up-regulating osmotin-like protein expression and inducing JA/SA signaling pathways.

BACKGROUND: Panax notoginseng (Burk) F. H. Chen is a valuable traditional Chinese medicinal plant, but its commercial production is seriously affected by root rot caused by some pathogenic fungi, including Fusarium solani. Nevertheless, the genetic breeding for disease resistance of P. notoginseng remains limited. The WRKY transcription factors have been revealed to play important roles in plant defense responses, which might provide an inspiration for resistance improvement in P. notoginseng. RESULTS: In this study, the regulatory mechanism of transcription factor PnWRKY15 on P. notoginseng resistance to F. solani infection was revealed. The suppressed expression of PnWRKY15 via RNA interference increased the sensitivity of P. notoginseng to F. solani and decreased the expression levels of some defense-related genes, including PnOLP1, which encodes an osmotin-like protein that confers resistance to F. solani. Ectopic expression of PnWRKY15 in the model plant tobacco significantly enhanced the resistance to F. solani. Moreover, the transcriptome sequencing analysis discovered that some pathogenesis-related genes were expressed at higher levels in the PnWRKY15-overexpressing tobacco than that in the wild-type tobacco. In addition, the jasmonic acid (JA) and salicylic acid (SA) signaling pathways were evidently induced by PnWRKY15-overexpression, that was evidenced by that the JA and SA contents were significantly higher in the PnWRKY15-overexpressing tobacco than that in the wild-type. Furthermore, PnWRKY15, which was localized in the nucleus, can trans-activate and up-regulate PnOLP1 expression according to the EMSA, yeast one-hybrid and co-expression assays. CONCLUSIONS: PnWRKY15 contributes to P. notoginseng resistance to F. solani by up-regulating the expression of resistance-related gene PnOLP1 and activating JA/SA signaling pathways. These findings will help to further elucidate the transcriptional regulatory mechanism associated with the P. notoginseng defense response to F. solani.

An MYB Transcription Factor Modulates Panax notoginseng Resistance Against the Root Rot Pathogen Fusarium solani by Regulating the Jasmonate Acid Signaling Pathway and Photosynthesis.

Root rot of Panax notoginseng, a precious Chinese medicinal plant, seriously impacts its sustainable production. However, the molecular regulatory mechanisms employed by P. notoginseng against root rot pathogens, including Fusarium solani, are still unclear. In this study, the PnMYB2 gene was isolated, and its expression was affected by independent treatments with four signaling molecules (methyl jasmonate, ethephon, salicylic acid, and hydrogen peroxide) as assessed by quantitative real-time PCR. Moreover, the PnMYB2 expression level was induced by F. solani infection. The PnMYB2 protein localized to the nucleus and may function as a transcription factor. When overexpressed in transgenic tobacco, the PnMYB2 gene conferred resistance to F. solani. Jasmonic acid (JA) metabolism and disease resistance-related genes were induced in the transgenic tobacco, and the JA content significantly increased compared with in the wild type. Additionally, transcriptome sequencing, Kyoto Encyclopedia of Genes and Genomes annotation enrichment, and metabolic pathway analyses of the differentially expressed genes in the transgenic tobacco revealed that JA metabolic, photosynthetic, and defense response-related pathways were activated. In summary, PnMYB2 is an important transcription factor in the defense responses of P. notoginseng against root rot pathogens that acts by regulating JA signaling, photosynthesis, and disease-resistance genes.

Biochar impacts on phosphorus cycling in rice ecosystem.

Biochar can affect the phosphorus (P) cycle in the rice ecosystem through various pathways. Pot experiments were conducted to investigate the risk of P contamination and the P supply rate to crops with the application of maize straw-derived biochar (BM) and P fertilizer. The biochar increased 18.3% and 8.45% total phosphorus (TP) concentration in the low-P level and high-P level soils, respectively. The addition of biochar increased the phosphorus activation coefficient (PAC) by 9.00% at low-P levels, while the PAC was reduced by 10.4% at high-P levels. The results suggested that biochar could serve as either a source or a sink for P. The P concentration in the dithionite-citrate-bicarbonate (DCB) extracts on the root surfaces in biochar-treated soils increased by 467.1% and 46.1% in the low-P level and high-P level soils, respectively. It may cause by the acidification of soils near the root and the increase in Fe plaque. The results also showed the addition of biochar increased the DCB-P concentration and subsequently promoted rice growth. The biochar additions enhanced bacterial community richness and diversity, while the P supplementations inhibited bacterial growth. Redundancy analysis (RDA) showed that available nitrogen (AN), Fe-P, Ca-P, P uptake and, DCB extracted Fe (DCB-Fe) were significantly correlated with microbial community composition and explained 46.8%, 37.1%, 38.0%, 37.5% and 36.7% of the total community variability, respectively. This study provided evidence that biochar might affect the P cycle by impacting the microbial community composition and the Fe-reducing processes in the rice ecosystem.

Cryptotanshinone downregulates the profibrotic activities of hypertrophic scar fibroblasts and accelerates wound healing: A potential therapy for the reduction of skin scarring.

Hypertrophic scar (HS) is a skin fibrotic disease that causes major clinically problematic symptoms. Cryptotanshinone (CT) is an important ingredient of Danshen (Salvia miltiorrhiza Bunge extract) that has been used to treat cardio-cerebral vascular diseases. Its clinical efficacy in HS remains unclear. To investigate whether CT can inhibit HS fibrosis, HS-derived fibroblastic cells (HSFs) were established and treated with or without CT. Type-collagen-I (Col1), type-collagen-III (Col3) and α-smooth muscle actin (α-SMA) expression were measured by western blot and real-time quantitative polymerase chain reaction. HSFs migration and contraction were assessed with the scratch assay and the fibroblast-populated collagen lattice (FPCL) contraction assay, respectively. Wound healing in CT-treated Balb/c mice was assessed by immunohistochemical analysis of collagen expression and Masson's trichrome staining analysis of collagen deposition. CT treatment of HSFs down-regulated Col1, Col3 and α-SMA mRNA and protein expression, HSFs migration, and HSFs contraction, and improved FPCL architecture. In mice, CT treatment accelerated wound healing: the scar margins were narrow and there was less collagen deposition in the regenerated tissue. Thus, CT promotes wound healing and decreases excessive deposition of extracellular matrix components. CT may help to prevent and reduce scarring.

Carbetocin for preventing postpartum haemorrhage.

BACKGROUND: Postpartum haemorrhage (PPH) is one of the major contributors to maternal mortality and morbidity worldwide. Active management of the third stage of labour has been proven to be effective in the prevention of PPH. Syntometrine is more effective than oxytocin but is associated with more side effects. Carbetocin, a long-acting oxytocin agonist, appears to be a promising agent for the prevention of PPH. OBJECTIVES: To determine if the use of oxytocin agonist is as effective as conventional uterotonic agents for the prevention of PPH, and assess the best routes of administration and optimal doses of oxytocin agonist. SEARCH METHODS: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (1 March 2011), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 1 of 4), MEDLINE (1966 to 1 March 2011) and EMBASE (1974 to 1 March 2011). We checked references of articles and communicated with authors and pharmaceutical industry contacts. SELECTION CRITERIA: Randomised controlled trials which compared oxytocin agonist (carbetocin) with other uterotonic agents or with placebo or no treatment for the prevention of PPH. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trials for inclusion, assessed risk of bias and extracted data. MAIN RESULTS: We included 11 studies (2635 women) in the review. Six trials compared carbetocin with oxytocin; four of these were conducted for women undergoing caesarean deliveries, one was for women following vaginal deliveries and one did not state the mode of delivery clearly. The carbetocin was administered as 100 µg intravenous dosage across the trials, while oxytocin was administered intravenously but at varied dosages. Four trials compared intramuscular carbetocin and intramuscular syntometrine for women undergoing vaginal deliveries. Three of the trials were on women with no risk factor for PPH, while one trial was on women with risk factors for PPH. One trial compared the use of intravenous carbetocin with placebo. Use of carbetocin resulted in a statistically significant reduction in the need for therapeutic uterotonics (risk ratio (RR) 0.62; 95% confidence interval (CI) 0.44 to 0.88; four trials, 1173 women) compared to oxytocin for those who underwent caesarean section, but not for vaginal delivery. Compared to oxytocin, carbetocin was associated with a reduced need for uterine massage following both caesarean delivery (RR 0.54; 95% CI 0.37 to 0.79; two trials, 739 women) and vaginal delivery (RR 0.70; 95% CI 0.51 to 0.94; one trial, 160 women). Pooled data also showed that carbetocin resulted in a lower risk of PPH compared to oxytocin in women who underwent caesarean delivery (RR 0.55; 95% CI 0.31 to 0.95; three trials, 820 women). This is, however, limited by the number of studies and risk of bias in the studies. Comparison between carbetocin and syntometrine showed a lower mean blood loss in women who received carbetocin compared to syntometrine (mean difference (MD) -48.84 ml; 95% CI -94.82 to -2.85; four trials, 1030 women). There was no statistically significant difference in terms of the need for therapeutic uterotonic agents, but the risk of adverse effects such as nausea and vomiting were significantly lower in the carbetocin group: nausea (RR 0.24; 95% CI 0.15 to 0.40; four trials, 1030 women); vomiting (RR 0.21; 95% CI 0.11 to 0.39; four trials, 1030 women). The incidence of postpartum hypertension was also significantly lower in women who received carbetocin compared to those who received syntometrine. Cost-effectiveness of carbetocin was investigated by one study published as an abstract, with limited data. AUTHORS' CONCLUSIONS: There is evidence to suggest that 100 µg of intravenous carbetocin is more effective than oxytocin for preventing PPH in women undergoing caesarean deliveries, but more studies are needed to validate this finding. Carbetocin is associated with less blood loss compared to syntometrine in the prevention of PPH for women who have vaginal deliveries and is associated with significantly fewer adverse effects. Further research is needed to analyse the cost-effectiveness of carbetocin as a uterotonic agent.