Comparative pharmacokinetics of a proliposome formulation of Ginkgo biloba extract and Ginaton in rats by a sensitive ultra performance liquid chromatography-tandem mass spectrometry method.

As a novel oral drug delivery system, proliposome was applied to improve the solubility of active components of Ginkgo biloba extract (GbE). There are currently few reports focusing on the pharmacokinetic characteristics of proliposome of GbE (GbP). A rapid and sensitive ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous quantification of active components of GbP and a commercial tablet product (Ginaton) in rat plasma was developed and successfully validated. The method was applied to the comparative pharmacokinetic evaluation of GbP and Ginaton in rat plasma. The results indicated that GbP has a significant effect on absorption, elimination and bioavailability of flavonoids and terpenoid lactones in comparison with Ginaton. The obtained results would be helpful for evaluating the absorption mechanism in the gastrointestinal tract in pharmacokinetic level and guiding the development of the novel oral drug delivery system.

Anti-diabetic activities of Paecilomyces tenuipes N45 extract in alloxan-induced diabetic mice.

Due to the limitations of existing anti-diabetic drugs, the treatment of diabetes mellitus remains a significant challenge. The present study aimed to investigate the hypoglycemic, hypolipidemic and antioxidant effects of Paecilomyces tenuipes N45 extracts on alloxan-induced type I diabetes mellitus in mice. Diabetic Kunming mice were orally administered with water extract (WE) at doses of 2.50, 0.25 and 0.05 g/kg) or alcohol extract (AE) at doses of 2.00, 0.20 and 0.04 g/kg, for 3 weeks, following which the levels of factors associated with blood glucose, lipids and free radicals were determined. The anti-diabetic activities of AE and WE were further confirmed via an oral glucose tolerance test. Similar to the effects of metformin, Paecilomyces tenuipes N45 extracts led to a significant reduction in blood glucose levels, increase in serum insulin concentration and normalization in the densities of low-density lipoprotein cholesterol and high density lipoprotein cholesterol. The Paecilomyces tenuipes N45 extracts exerted antioxidative effects, indicated by regulation in the levels of superoxide dismutase, malondialdehyde and glutathione peroxidase. Taken together, the results of the present study demonstrated that Paecilomyces tenuipes N45 extract, a safe pharmaceutical agent, exerted anti-diabetic and anti-nephropathic activities and, thus, offers potential as a novel therapeutic agent in the treatment of diabetes.

Nonresonant chemical mechanism in surface-enhanced Raman scattering of pyridine on M@Au12 clusters.

By employing density functional theory (DFT), this study presents a detailed analysis of nonresonant surface-enhanced Raman scattering (SERS) of pyridine on M@Au12 (M = V(-), Nb(-), Ta(-), Cr, Mo, W, Mn(+), Tc(+), and Re(+))-the stable 13-atom neutral and charged gold buckyball clusters. Changing the core atom in M@Au12 enabled us to modulate the direct chemical interactions between pyridine and the metal cluster. The results of our calculations indicate that the ground-state chemical enhancement does not increase as the binding interaction strengthens or the transfer charge increases between pyridine and the cluster. Instead, the magnitude of the chemical enhancement is governed, to a large extent, by the charged properties of the metal clusters. Pyridine on M@Au12 anion clusters exhibits strong chemical enhancement of a factor of about 10(2), but the equivalent increase for pyridine adsorbed on M@Au12 neutral and cation clusters is no more than 10. Polarizability and deformation density analyses clearly show that compared with the neutral and cation clusters, the anion clusters have more delocalized electrons and occupy higher energy levels in the pyridine-metal complex. Accordingly, they produce larger polarizability, leading to a stronger nonresonant enhancement effect.

Mitochondria Related Pathway Is Essential for Polysaccharides Purified from Sparassis crispa Mediated Neuro-Protection against Glutamate-Induced Toxicity in Differentiated PC12 Cells.

The present study aims to explore the neuro-protective effects of purified Sparassis crispa polysaccharides against L-glutamic acid (L-Glu)-induced differentiated PC12 (DPC12) cell damages and its underlying mechanisms. The Sparassis crispa water extract was purified by a DEAE-52 cellulose anion exchange column and a Sepharose G-100 column. A fraction with a molecular weight of 75 kDa and a diameter of 88.9 nm, entitled SCWEA, was obtained. SCWEA was identified with a triple helix with (1→3)-linked Rha in the backbone, and (1→2) linkages and (1→6) linkages in the side bone. Our results indicated that the pre-treatment of DPC12 cells with SCWEA prior to L-Glu exposure effectively reversed the reduction on cell viability (by 3-(4,5-cimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay) and reduced L-Glu-induced apoptosis (by Hoechst staining). SCWEA decreased the accumulation of intracellular reactive oxygen species, blocked Ca(2+) influx and prevented depolarization of the mitochondrial membrane potential in DPC12 cells. Furthermore, SCWEA normalized expression of anti-apoptotic proteins in L-Glu-explored DPC12 cells. These results suggested that SCWEA protects against L-Glu-induced neuronal apoptosis in DPC12 cells and may be a promising candidate for treatment against neurodegenerative disease.

Development of hair cells in inner ear is associated with expression and promoter methylation of Notch-1 in postnatal mice.

The present study was designed to investigate the correlation among the number of hair cells in inner ear, Notch-1 gene expression levels and its methylation status of the promoter region in the postnatal mice. The hair cells in inner ear were collected from postnatal mice at day 0, 4, 8 and 16 and counted by immunofluorescence. Notch-1 mRNA expression were measured by real-time quantitative polymerize chain reaction (PCR). Methylation levels of CpG islands in Notch-1 promoters were analyzed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry. The results showed that the number of hair cells in the inner ear increased gradually after birth, which were positively correlated to Notch-1 mRNA expression. However, analysis on methylation of CpG sites in Notch-1 promoter showed that the methylation rates increased gradually after births, which were correlated with the decreased expression of Notch-1. Drug lesion induced the loss of hair cells, and stimulated the expression of Notch-1 mRNA expression, but didn't influence the methylation rates of Notch-1 promoter. We concluded that the Notch-1 mRNA expression level in inner ear tissues is correlated with the development of hair cells. CpG islands in Notch-1 promoter region manifest hypermethylation status when hair cells in inner ear are mature.

Enzymo-chemical preparation, physico-chemical characterization and hypolipidemic activity of granular corn bran dietary fibre.

Corn bran dietary fibre (CF) was paid more attention for its anticancer and hypolipidemic activities. In this paper, corn bran was firstly decomposed to the threadlike fibre (CF1) by multiple enzymes and then further modified to the granular fibre (CF2) by alkali under high pressure and high temperature (APT). The two types of fibres were characterized by scanning electron microscope (SEM) and near-infrared spectrophotometer (IR), and investigated by hydration measurements and nitrite adsorption assays. The results showed that CF2 had more much specific surface area, and displayed 4.7, 6.3 and 30-fold increases in water retention (WR), swelling capacity (SC) and nitrite absorption (NA), compared with CF1, respectively. The rat feeding trials showed that the granular fibre could decrease total cholesterol (TC), triglyceride (TG) and low density lipoprotein-cholesterol (LDLC) by 41.4 %, 20.7 % and 56.5 %, respectively. These excellent physiological activities indicate that CF2 will be a potentially available dietary ingredient in functional food industries, and meanwile imply that the enzymochemical method is a desired strategy for CF processing.

Purification of polysaccharides from Cordyceps militaris and their anti­hypoxic effect.

Acute mountain sickness, one of the most common altitude diseases, causes lung and brain injury. The present study aimed to investigate the anti­hypoxic effect of purified polysaccharides extracted from Cordyceps militaris. The aqueous extract of Cordyceps militaris was purified progressively through a DEAE­52 cellulose anion exchange column and a Sepharose G­100 column. The fraction CMN1, with a molecular weight of 37842 Da, was the main fraction obtained and its chemical composition and structural characteristics were determined. CMN1 was found to have a monosaccharide composition of L­rhamnose, L­arabinose, D­mannose, D­galactose. The backbone of CMN1 comprised (1→2) and (1→3) linkages, with branched (1→6) and (1→4) linkages. The anti­hypoxic effects of CMN1 were determined using a sodium nitrite toxicosis test, acute cerebral ischemic/hypoxic test and normobarie hypoxia test. CMN1 (0.5 g/kg) possessed a similar anti­hypoxic effect to rhodiola oral liquid. Overall, the Cordyceps militaris polysaccharide, CMN1, was identified as an effective agent against hypoxia.

Studies on the antidiabetic activities of Cordyceps militaris extract in diet-streptozotocin-induced diabetic Sprague-Dawley rats.

Due to substantial morbidity and high complications, diabetes mellitus is considered as the third "killer" in the world. A search for alternative antidiabetic drugs from herbs or fungi is highly demanded. Our present study aims to investigate the antidiabetic activities of Cordyceps militaris on diet-streptozotocin-induced type 2 diabetes mellitus in rats. Diabetic rats were orally administered with water extract or alcohol extract at 0.05 g/kg and 2 g/kg for 3 weeks, and then, the factors levels related to blood glucose, lipid, free radicals, and even nephropathy were determined. Pathological alterations on liver and kidney were examined. Data showed that, similar to metformin, Cordyceps militaris extracts displayed a significant reduction in blood glucose levels by promoting glucose metabolism and strongly suppressed total cholesterol and triglycerides concentration in serum. Cordyceps militaris extracts exhibit antioxidative effects indicated by normalized superoxide dismutase and glutathione peroxidase levels. The inhibitory effects on blood urea nitrogen, creatinine, uric acid, and protein revealed the protection of Cordyceps militaris extracts against diabetic nephropathy, which was confirmed by pathological morphology reversion. Collectively, Cordyceps militaris extract, a safe pharmaceutical agent, presents excellent antidiabetic and antinephropathic activities and thus has great potential as a new source for diabetes treatment.

H-NOX domains display different tunnel systems for ligand migration.

Soluble guanylate cyclase (sGC) displays a high affinity for its physiological ligand (NO), but the ability of O(2) binding is not identified even if the presence of a large excess O(2) in vivo. Therefore, discrimination against O(2) by sGC is essential for NO signaling. Recently, the heme domain of sGC was termed as a member of new conversed hemoprotein family, namely H-NOX domain. Various ligand binding properties of H-NOX domains were observed and some of them bind O(2) tightly, whereas others have a poor affinity for O(2) or even no measurable affinity for O(2) at all like sGC. Several crystal structures of H-NOX domains are available now in both NO-bound form (Ns H-NOX; PDBid 2O0C) and O(2)-bound form (Tt N-NOX; PDBid 1U55). These structures provide an ideal data for elucidating the molecular detail of ligand discrimination in H-NOX domains. In this work, by employing the locally enhanced sampling molecular dynamics (LESMD) simulations, we compared the ligand migration pathways between Ns H-NOX and Tt H-NOX. Interestingly, although they are similar in fold, the different spatial distributions of ligands between Ns H-NOX and Tt H-NOX are explored and proposed for ligand discrimination. The residue at position M144 in Ns H-NOX plays a key role in controlling the ligand entry and escape. However, in Tt H-NOX, the same position is a hydrogen-bonding tyrosine for stabilizing the oxygen binding and its steric effects of blocking the ligand migration is remarkable.