[Protective effect of Asarum polysaccharide on H1N1 influenza virus infection and expression of inflammatory factors].

In this paper, Asarum polysaccharides(AP) were extracted, and its composition was analyzed to study the activity against H1 N1 influenza virus in vitro and its intervention effect on mice with kidney Yang deficiency syndrome. AP was prepared by the strategy of water extraction and alcohol precipitation, the content was determined, and its monosaccharide composition was analyzed. The cell Real-time monitoring system and Reed-Muench model were adopted to evaluate the antiviral activity of AP in vitro. And the mouse model of kidney Yang deficiency syndrome was established in vivo to compare the efficacy of Mahuang Xixin Fuzi Decoction(MXF) and AP. MXF group and AP group were treated with clinical equivalent doses of 1.8 g·kg~(-1)·d~(-1) and 0.077 g·kg~(-1)·d~(-1) respectively, once a day for 6 consecutive days. Real-time PCR was used to detect the relative expression of M gene of H1 N1 influenza virus and cytokines in lung tissue. The content of AP in Asarum was 25.22%, and the protein content was 0.8%. And the monosaccharide composition was identified as L-rhamnose, D-arabinose, D-xylose, D-glucose, D-galactose and D-mannose. TI values of Tamiflu, MXF and AP were 30.00, 8.06 and 10.33, respectively. Three different doses of AP could significantly reduce the concentration of virus in supernatant. Compared with the model mice, lung indexes of MXF group and AP group decreased significantly(P<0.05), and the relative expression of M gene decreased significantly(P<0.05). The relative expressions of IL-10 and IFN-γ were up-regulated to varying degrees, while the relative gene expressions of IL-1ß, IL-6 and MCP-1 were down-regulated to different degrees. In addition, AP could significantly enhance the expression of TNF-α(P<0.01). AP had a good anti-influenza virus activity in vitro, and could protect mice with kidney Yang deficiency syndrome by reducing the viral load in lung tissue, decreasing inflammation damage in lung tissue, and regulating the expression of inflammatory cytokines. Compared with the prescription of MXF, AP had a better antiviral activity.

Selection and validation of optimal endogenous reference genes for analysis of quantitative PCR in four tissues pathologically associated with Kidney-yang deficiency syndrome following influenza A infection.

Kidney-yang deficiency syndrome (KYDS) infected with the influenza virus is a suitable model to imitate a population at high-risk to influenza infection with a high rate of morbidity and mortality. However, the specific molecular mechanisms underlying this disease remain unclear. A stable reference gene is essential as an internal control for molecular biology research of this condition. Reverse-transcription-quantitative PCR (RT-qPCR) is considered an extremely sensitive technique used for absolute and relative quantification of target genes transcript levels. To accurately estimate the relative expression of genes in cells from mice with KYDS in response to infection with influenza A virus subtype H1N1 (A/H1N1) virus using RT-qPCR, it is necessary to identify suitable reference genes. In the present study, analysis of 10 reference genes (Act-ß, ß2m, GAPDH, Gusß, Tubα, Grcc10, Eif4h, Rnf187, Nedd8 and Ywhae) was performed across a set of 4 tissue types: Lung; heart; liver; and kidney. KYDS mice were inoculated with A/H1N1 virus or a mock control. For analysis, geNorm, BestKeeper, NormFinder, and Bio-Rad Maestro™ statistical programs were used for the estimation of the stability of the reference genes. The results were authenticated through extended experimental settings using a group of 10 samples, parallel to 3 additional innate immune system-associated genes of the host, TLR3, TLR7 and RIG-I, which were also analyzed using the same algorithms. From the 4 algorithms, taking into account the joint analyses of the ranking order outputs, the 2 genes Ywhae and Nedd8 were identified to be the most stable for mice with KYDS following infection with A/H1N1 virus. In contrast, the least stable genes in all 4 tissues were GAPDH and ß2m. These results may affect the choice of reference genes in future studies that use RT-qPCR analysis of target genes in experimental conditions, such as mice with KYDS infected with influenza A virus.

A Novel Strategy Facilitates Reference Gene Selection by RT-qPCR Analysis in Kidney Yang Deficiency Syndrome Mice Infected with the Influenza A (H1N1) Virus.

In reverse transcription-quantitative polymerase chain reaction (RT-qPCR) studies, endogenous reference genes are routinely used to normalize the expression of target gene studies. In order to precisely evaluate the relative expression of genes in the cells of mice suffering from Kidney Yang Deficiency Syndrome (KYDS) in response to influenza A virus (IAV) H1N1 using RT-qPCR, it is crucial to identify reliable reference genes. In the present study, 15 candidate reference genes (Actb, ß2m, Gapdh, Gusb, Tuba, Grcc10, Eif4h, Rnf187, Nedd8, Ywhae, 18S rRNA, Rpl13, Ubc, Rpl32, and Ppia) were investigated in lung cells from KYDS mice infected with IAV H1N1. NormFinder, BestKeeper, and GeNorm were used to assess the stability of reference genes. The results were authenticated over extended experimental settings by a group of 10 samples. In the present study, we explored a novel method using dual-gene combinations; the difference in gene expression between the model and normal control groups was statistically analyzed by an independent-samples t-test, and the difference in the mean value between the two groups was compared. A P value > 0.05 and the lowest absolute value of the difference indicated the optimal reference two-gene combination. Four additional host innate immune system-related genes (TLR3, TLR4, TLR7, and RIG-I) were analyzed together with the two treatment datasets to confirm the selected reference genes. Our results indicated that none of these 15 candidate reference genes can be used as reference gene individually for relative quantitative fluorescence PCR analysis; however, the combination of Grcc10 and Ppia, based on the process of calculating the higher P value and lower difference values between groups, was the best choice as a reference gene for the lung tissue samples in KYDS mice infected with IAV. This technique may be applied to promote the selection process of the optimal reference gene in other experiments.

Isolation, purification, structural analysis and biological activities of water-soluble polysaccharide from Glehniae radix.

A new polysaccharide named GRP (Glehniae radix polysaccharide) was isolated and purified from Glehniae radix by hot water extraction, ethanol precipitation, anion-exchange and gel-filtration chromatography. GRP was homogeneous, with a molecular weight of 1.33×104Da, as determined by high-performance size-exclusion chromatography-refractive index detector analysis. Its structural characteristics were investigated and elucidated by methylation analysis, gas chromatography mass spectrometry, Fourier transform infrared and nuclear magnetic resonance spectroscopy. Based on obtained data, GRP was found to be α­d­glucan containing (1→6)-linked and (1→3)-linked backbone with a branch of one (1→6)-linked and terminal glucoses submitting at the C-4 position every fourteen residues. The biological activities of GRP upon proliferation of splenic lymphocyte, RAW264.7 cells and A549 cell, and production of nitric oxide (NO) were investigated in vitro. The results showed that GRP exhibited inhibition against A549 cells proliferation and NO production in RAW264.7 cells, and displayed promotion for proliferation of mouse spleen lymphocytes and RAW264.7 cells, which suggested that GRP may have potential immunoregulation, anti-inflammatory and anti-tumor activity.

[Structural characterization of Glehniae Radix polysaccharides using partial acid hydrolysis-hydrophilic interaction liquid chromatography-mass spectrometry].

Water-soluble polysaccharides from traditional Chinese medicine have properties of complex structure and high molecular, resulting in hardly complete their structural characterization.However, a "bottom-up" approach could solve this problem.Glehniae Radix extract was extracted with hot water and then precipitated by 40% ethanol to obtain Glehniae Radix polysaccharides (RGP). Subsequently, a partial acid hydrolysis method was carried out and the effects of acid concentration, time and temperature on hydrolysis were investigated. Under the optimum hydrolysis condition (1.5 mol•L⁻¹ trifluoroacetic acid, 4 h, and 80 ℃), RGP were hydrolyzed to characteristic oligosaccharide fragments. Futher, a hydrophilic liquid chromatography- mass spectrometry method was used for the separation and structural characterization of the polysaccharide hydrolysates. According to MS and MS/MS analysis of several standard disaccharides, a method for determining the type of polysaccharide glycosidic linkage by mass spectrometry was established. The results showed that the polysaccharide hydrolysates were linear glucan containing 1, 4-glycosidic bonds. And gluco-oligosaccharides with the degrees of polymerization (DP) of 4-11 were obtained after partial acid hydrolysis.