Nonalcoholic steatohepatitis (NASH) is the most frequent cause of liver dysfunction and a common global problem. Gypenosides can decrease pathological modifications of high-fat diet-induced rat atherosclerosis; however, its effect and mechanism on NASH remain unclear. In this study, rats were randomly divided into normal control and model groups. Model rats were fed with a high-fat diet and treated with gypenosides, rosiglitazone, or water for 6 weeks. We found that liver tissues showed significant hepatic steatosis and vacuolar degeneration with significantly higher triglyceride (TG), free fatty acid (FFA) and malonyl CoA, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT) activities in model group versus normal control group (p<0.01). Liver tissue mRNA and protein levels of sterol regulatory element binding protein-1c (SREBP-1c), carbohydrate response element binding protein (ChREBP), acetyl-CoA carboxylase (ACCase), and stearoyl CoA desaturase enzyme 1 (SCD1) were significantly increased, while the carnitine palmitoyl transferase-1 (CPT-1) level was significantly decreased in the model group versus the normal control group (p<0.01). Pathological changes of hepatic steatosis; body weight and liver wet weight; liver tissue TG, FFA and malonyl CoA concentrations; serum ALT, AST and GGT activities; liver tissue mRNA and protein levels of SREBP-1c, ChREBP, ACCase, and SCD-1 were significantly decreased; protein and mRNA levels of CPT-1 were significantly increased in the gypenosides group versus model group (p<0.01). In conclusion, gypenosides has therapeutic effect on NASH through regulating key transcriptional factors and lipogenic enzymes involved in fatty acid oxidation during hepatic lipogenesis.

Cross-reactive anti-flaviviral immunity can influence the outcome of infections with heterologous flaviviruses. However, it is unclear how the interplay between cross-reactive antibodies and T cells tilts the balance toward pathogenesis versus protection during secondary Zika virus (ZIKV) and Japanese encephalitis virus (JEV) infections. We show that sera and IgG from JEV-vaccinated humans and JEV-inoculated mice cross-reacted with ZIKV, exacerbated lethal ZIKV infection upon transfer to mice, and promoted viral replication and mortality upon ZIKV infection of the neonates born to immune mothers. In contrast, transfer of CD8+ T cells from JEV-exposed mice was protective, reducing the viral burden and mortality of ZIKV-infected mice and abrogating the lethal effects of antibody-mediated enhancement of ZIKV infection in mice. Conversely, cross-reactive anti-ZIKV antibodies or CD8+ T cells displayed the same pathogenic or protective effects upon JEV infection, with the exception that maternally acquired anti-ZIKV antibodies had no effect on JEV infection of the neonates. These results provide clues for developing safe anti-JEV/ZIKV vaccines.

A growing body of evidence has shown the beneficial effects of salidroside in cardiovascular and metabolic diseases. This study aimed to evaluate the therapeutic effects of salidroside on nonalcoholic steatohepatitis (NASH) in rats and explore the underlying mechanisms related to insulin signaling. A rat model of NASH was developed by high-fat diet for 14 weeks. From week 9 onward, the treatment group received oral salidroside (4.33 mg/kg) daily for 6 weeks. Salidroside effectively attenuated steatosis and vacuolation of hepatic tissue, with a dramatic decrease in liver triglycerides and free fatty acid levels (P < 0.01). Dysregulation of FINS, FBG, HOMA-IR, ALT, and AST in serum was ameliorated with salidroside treatment (P < 0.01). In the liver, salidroside induced significant increases in key molecules in the insulin signaling pathway, such as phosphorylated insulin receptor substrate 1 (IRS1), phosphoinositide 3-kinase (PI3K), and protein kinase B (PKB), with a significant decrease in SREBP-1c levels (P < 0.01). Therefore, salidroside effectively protected rats from high-fat-diet-induced NASH, which may be partially attributed to its effects on the hepatic insulin signaling pathway.

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Background: Rhizoctonia solani causes stem canker and significantly impacts the production of potato. Conventional assay to evaluate potato resistance using R. solani inoculum is time consuming. To establish an effective and fast assay, 20 potato germplasms were examined using both R. solani inoculum and R. solani-derived toxin (RS toxin). Results: In field trials of 2009 and 2010, wheat-bran-based inoculum of R. solani was incorporated at either 0, 2, 3, 4 or 5 g per seed piece in the soil followed by sowing potato seed pieces in the furrow. Stem canker was evaluated in the growing season. Inoculum of wheat-bran-based 2, 3, or 4 g could well distinguish resistance of potato germplasms. For a quick assay of resistance screening, a toxin-based method was established by treating potato seedlings with the toxin of R. solani (RS toxin). RS toxin was prepared by heating R. solani culture. Potato seedlings were obtained through tissue culture and grown in Murashige and Skoog medium. Seedlings at the stage of 12 cm in height were transferred into agar medium amended with RS toxin and incubated for eight days. The inhibition caused by RS toxin was positively correlated with toxin concentration. By evaluating various potato cultivars that have different sensitivities to toxin, the inhibition of potato stems sections and seedlings was from 33% to 100% and from 32% to 148%, respectively. Results of toxin-based evaluation were highly correlated with the field data using pathogen inoculum (r = 0.731, P < 0.01). Conclusions: Inoculation with wheat bran-mediated R. solani of 2, 3 or 4 g per seed piece was an effective method for the evaluation of potato resistance in field trials. The toxin-based assay could improve efficiency and speed of disease resistance evaluation of potato germplasms. Both assays showed that none of the 20 potato materials was completely resistant to R. solani. However, cultivar ‘Desiree’ had the lowest level of disease, whereas ‘Atlantic’, ‘Favorita’, and ‘Shepody’ showed the high susceptibility.