Effect of Oat and Tartary Buckwheat - Based Food on Cholesterol - Lowering and Gut Microbiota in Hypercholesterolemic Hamsters.

The nutritional components in oat and tartary buckwheat had been assessed to have cholesterollowering effects. However, The effect of oat and tartary buckwheat based-food (OF) on cholesterol-lowering and gut microbiota in hypercholesterole hamsters was still limited studied because they are usually consumed in whole gran as well as after being processed. In this study, normal diets, high fat diet (HFD) with/without OF were fed to hamsters for 30 days respectively and growth parameters, metabolic parameters, and gut microbiota were investigated, respectively. It was found that OF significantly decreased plasma total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-cholesterol), lowered liver TC, cholesterol ester (CE), and triglycerides (TG) concentrations, and increased fecal weight and bile acids (BA) concentrations, compared with HFD (p < 0.05). Moreover, the concentrations of acetate, propionate, butyrate and total short-chain fatty acids (SCFAs) were significantly increased in hamsters fed with OF, compared with HFD (p < 0.05). OF changed the overall structure of gut microbiota. The relative abundances of Erysipelotrichaceae, Ruminococcaceae, and Lachnospiraceae were decreased and the relative abundance of Eubacteriaceae was increased, compared with HFD. These results suggested that OF could reduce the concentrations of plasma lipid by inhibiting cholesterol absorption in liver and promoting excretions of fecal lipid and BA. And it also increased SCFAs and modulated the gut microbiota effectively to exert the hypocholesterolemic effects.

Modeling Analysis of Potential Target of Dolastatin 16 by Computational Virtual Screening.

Dolastatin 16 is a cyclic depsipeptide isolated from the marine invertebrates and cyanobacterium Lyngbya majuscula, however, its bioactivity has been a historical question. In this study, peptidyl-prolyl cis-trans isomerase FKBP1A (FKBP12) was predicted as a potential target of dolastatin 16 via PharmMapper as well as verified using chemical-protein interactome (CPI) and molecular docking. FKBP1A has been previously identified as a target for the natural polyketide FK506 (tacrolimus), an immune suppressor inhibiting the rejection of organ transplantation in clinical use. The comparison study via the reverse pharmacophore screening and molecular docking of dolastatin 16 and FK506 indicated the good consistency of analysis with the computational approach. As the results, the lowest binding energy of dolastatin 16-FKBP1A complex was -7.4 kcal/mol and FK506-FKBP1A complex was -8.7 kcal/mol. The ligand dolastatin 16 formed three hydrogen bonds vs. four of FK506, as well as seven hydrophobic interactions vs. six of FK506 within the active site residues. These functional residues are highly repetitive and consistent with previously reported active site of model of FK506-FKBP1A complex, and the pharmacophore model was shown feasibly matching with the molecular feature of dolastatin 16.

Immobilized capillary tyrosinase microreactor for inhibitor screening in natural extracts by capillary electrophoresis.

A method for creating an immobilized capillary tyrosinase (TRS) reactor based on a layer-by-layer (LBL) assembly for inhibitor screening is described. Tyrosinase was immobilized on the surface of fused-silica capillary via ionic binding technique with cationic polyelectrolyte hexadimethrine bromide (HDB). Then, HDB solution with the same plug length as the TRS was injected again into the capillary to cover the immobilized enzyme by forming HDB-TRS-HDB sandwich-like structure. Then, the substrate of l-tyrosine was introduced into the capillary and on-line enzyme inhibition study was performed by capillary electrophoresis (CE). The enzyme activity was determined by the quantification of peak area of the product of l-DOPA. Enzyme inhibition can be read out directly from the reduced peak area of the product in comparison with a reference electropherogram obtained in the absence of any inhibitor. The immobilized enzyme could withstand 25 consecutive assays by only losing 12% activity. A known TRS inhibitor, kojic acid was employed as a model compound for the validation of the inhibitor screening method. Finally, screening 19 natural extracts of traditional Chinese drugs was demonstrated. The results indicated that inhibition activity could be straightforwardly identified with the system.

Effect of the Miaoyao Fanggan sachet-derived isorhamnetin on TLR2/4 and NKp46 expression in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Miaoyao Fanggan Sachets (MFS) has long been used as a folk medicine for the prevention of influenza in Southeast of Guizhou Province, China. However, the precise immunological mechanisms by which MFS confers protection have not been defined. STUDY AIM: To explore the effects of MFS on innate immune system responses using a cold stress-induced immune impairment model as a means of examining MFS-mediated influenza prevention. We investigated the effects of MFS on toll-like receptor 2 and 4 (TLR2/4) gene and protein expression levels and on the percentage of NKp46(+) cells present in serum. No overt toxicity was observed following continuous administration of MFS at high doses. METHODS: Kunming male mice (n=40) were randomly divided into 4 groups consisting of the continuous inhalation Sachet group, Yu-Ping-Feng powder (YPF-P) gavage positive control group, discontinuous inhalation MFS group and untreated controls. After 4 weeks, mice were sacrificed and lungs harvested. The expression of toll-like receptors 2 and 4 (TLR2/4) gene and protein levels was assessed using real-time polymerase chain reaction (RT-PCR) and Western blot analyses, respectively. An additional 60 Kunming mice were randomly divided into 6 groups comprised of a blank control group, continuous MFS inhalation group, an immune-compromised continuous MFS inhalation group, an immuno-compromised group, an immune-compromised MFS discontinuous inhalation group and an immune-compromised positive control group. Immune suppression was induced by cold stress (4 °C/4 h daily for 3 days) and mice were treated with MFS or YPF-P before cold stress treatments. Immuno-compromised mice were treated with MFS continuously or intermittently, or treated with YPF-P. Blood samples were collected and examined for natural killer cells based on positive NKp46 staining. The isorhamnetin associated with MFS-induced immune modulation was obtained from 'wo ga le' which is considered to be a major component of MFS, and analyzed by HPLC. RESULTS: Mice continuously inhaling MFS showed a moderate increase in TLR2/4 mRNA and protein levels compared to mice in the control and discontinuous inhalation groups. MFS significantly increased the TLR2/4 expression in a dose-dependent manner. Furthermore, there was also a slightly significant increase in the number of NKp46(+) cells in the continuous inhalation group compared to controls and discontinuous inhalation group. Pretreatment with MFS partially prevented cold stress-induced inhibition of NKp46(+) cells. HPLC analysis of the 'wo ga le' associated with immune function identified the major component to be isorhamnetin. CONCLUSIONS: Taken together, these data suggested that MFS significantly enhanced TLR2/4 expression levels and the number of NKp46(+) cells in mice and moderately affected innate immune responses associated with protection against influenza, suggesting that isorhamnetin in the MFS enhanced innate immune potency. The use of MFS for the prevention of various respiratory tract infections can be attributed to its antimicrobial properties. In a pilot study, a large quantity (40 g) was administered over a prolonged period did not produce apparent toxicity.