Mechanism of anti-hyperuricemia of isobavachin based on network pharmacology and molecular docking.

BACKGROUND: Hyperuricemia is a more popular metabolic disease caused by a disorder of purine metabolism. Our previous study firstly screened out a natural product Isobavachin as anti-hyperuricemia targeted hURAT1 from a Chinese medicine Haitongpi (Cortex Erythrinae). In view of Isobavachin's diverse pharmacological activities, similar to the Tranilast (as another hURAT1 inhibitor), our study focused on its potential targets and molecular mechanisms of Isobavachin anti-hyperuricemia based on network pharmacology and molecular docking. METHODS: First of all, the putative target genes of compounds were screen out based on the public databases with different methods, such as SwissTargetPerdiction, PharmMapper and TargetNet,etc. Then the compound-pathways were obtained by the compounds' targets gene from David database for Gene Ontology (GO) function enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways enrichment analysis. The cross pathways of compound-pathways and the diseases pathways of hyperuricemia from Comparative Toxicogenomics Database were be considered as the compound-disease pathways. Next, based on the compound-disease pathways and the PPI network, the core targets were identified based on the retrieved disease-genes. Finally, the compound-target-pathway-disease network was constructed by Cytoscape and the mechanism of isobavachin anti-hyperuricemia was discussed based on the network analysis. RESULTS: Our study demonstrated that there were five pathways involved in Isobavachin against hyperuricemia, including Drug metabolism-other enzymes, Metabolic pathways, Bile secretion, Renin-angiotensin system and Renin secretion. Among the proteins involved in these pathways, HPRT1, REN and ABCG2 were identified as the core targets associated with hyperuricemia, which regulated the five pathways mentioned above. It is quite different from that of Tranilast, which involved in the same pathways except Bile secretion instead of purine metabolism. CONCLUSION: This study revealed Isobavachin could regulate the pathways including Drug metabolism-other enzymes, Metabolic pathways, Bile secretion, Renin-angiotensin system, Renin secretion by core targets HPRT1, REN and ABCG2, in the treatment of hyperuricemia effect. Among them, the Bile secretion regulated by ABCG2 probably would be a novel pathway. Our work provided a theoretical basis for the pharmacological study of Isobavachin in lowering uric acid and further basic research.

Standardized myrtol attenuates lipopolysaccharide induced acute lung injury in mice.

CONTEXT: Standardized myrtol, an essential oil containing primarily cineole, limonene and α-pinene, has been used for treating nasosinusitis, bronchitis and chronic obstructive pulmonary disease (COPD). OBJECTIVE: To investigate the effects of standardized myrtol in a model of acute lung injury (ALI) induced by lipopolysaccharides (LPS). MATERIALS AND METHODS: Male BALB/c mice were treated with standardized myrtol for 1.5 h prior to exposure of atomized LPS. Six hours after LPS challenge, lung injury was determined by the neutrophil recruitment, cytokine levels and total protein concentration in the bronchoalveolar lavage fluid (BALF) and myeloperoxidase (MPO) activity in the lung tissue. Additionally, pathological changes and NF-κB activation in the lung were examined by haematoxylin and eosin staining and western blot, respectively. RESULTS: In LPS-challenged mice, standardized myrtol at a dose of 1200 mg/kg significantly inhibited the neutrophile counts (from 820.97 ± 142.44 to 280.42 ± 65.45, 103/mL), protein concentration (from 0.331 ± 0.02 to 0.183 ± 0.01, mg/mL) and inflammatory cytokines level (TNF-α: from 6072.70 ± 748.40 to 2317.70 ± 500.14, ng/mL; IL-6: from 1184.85 ± 143.58 to 509.57 ± 133.03, ng/mL) in BALF. Standardized myrtol also attenuated LPS-induced MPO activity (from 0.82 ± 0.04 to 0.48 ± 0.06, U/g) and pathological changes (lung injury score: from 11.67 ± 0.33 to 7.83 ± 0.79) in the lung. Further study demonstrated that standardized myrtol prevented LPS-induced NF-κB activation in lung tissues. DISCUSSION AND CONCLUSION: Together, these data suggest that standardized myrtol has the potential to protect against LPS-induced airway inflammation in a model of ALI.

[Effect of methylprednisolone pretreatment on pulmonary permeability and dipalmitoylphosphatidylcholine content in rabbits with reexpansion pulmonary edema].

OBJECTIVE: To investigate the effects of methylprednisolone pretreatment on pulmonary lung permeability index and the content of the pulmonary surfactant dipalmitoylphosphatidylcholine (DPPC) in a rabbit model of reexpansion pulmonary edema. METHODS: Twenty-one male New Zealand white rabbits were randomly divided into control group, reexpansion, and reexpansion+methylprednisolone pretreatment groups. The rabbit model of reexpansion pulmonary edema was established using Sakaos method. A bolus dosage of methylprednisolone (3 mg/kg) in reexpansion+methylprednisolone group group or 2.0 ml/kg normal saline in the other two groups was administered intravenously 20 min before reexpansion pulmonary edema. Bronchoalveolar lavage fluid (BALF) and arterial blood samples were collected for measurement of the total protein (TP) and DPPC contents 4 h after reexpansion, and the pulmonary permeability index was calculated. RESULTS: The pulmonary permeability index in methylprednisolone pretreatment group was significantly lower than that in the reexpansion group (0.007∓0.002 vs 0.177∓0.004, P<0.05). Methylprednisolone pretreatment significantly increased DPPC concentration in the BALF as compared with saline treatment in the reexpansion group (61.815∓28.307 vs 101.955∓24.544 µg/ml, P<0.05). CONCLUSION: Methylprednisolone pretreatment can increase pulmonary surfactant content and improve pulmonary permeability in the rabbit model of reexpansion pulmonary edema.

[Measurement of plasma concentration and bioavailability of nolatrexed dihydrochloride in mice].

OBJECTIVE: To establish a methods based on high-performance liquid chromatogram-mass spectrum for measuring the plasma concentration of nolatrexed dihydrochloride and investigate the pharmacokinetic profile and absolute bioavailability of the drug in mice. METHODS: Nolatrexed dihydrochloride were injected intravenously at 50 mg/kg or administered orally at 200 mg/kg in mice, and blood samples were collected at various time points following drug administration. The plasma concentration of nolatrexed dihydrochloride in mice was determined using high-performance liquid chromatogram-mass spectrum. The pharmacokinetic parameters were calculated using DAS software, and the absolute bioavailability of orally and intravenously administered was assessed according to the ratio of their area under the curve (AUC). RESULTS: The method showed good linear relationship within the drug concentration range of 0.01-40 mg/L (r=0.9995, P<0.001). The recovery of nolatrexed dihydrochloride from the mouse plasma was more than 85%, and the intra- and inter-day precision expressed as the relative standard deviation was less than 15%. The half-life (T(1/2)), AUC, distribution factor and plasma clearance (CL) for intravenously administered nolatrexed dihydrochloride (50 mg/kg) were 3.020-/+0.017 h, 89.972-/+0.425 mg/L/h, 0.831-/+0.106 L/kg, and 0.556-/+0.093 L/h/kg, respectively. The T(1/2), AUC, peak time (T(max)) and peak concentration (C(max)) for orally administered drug were 5.046-/+0.191 h, 84.893-/+9.923 mg/L/h, 1.000-/+0.012 h, and 18.000-/+0.0140 mg/L, respectively. The absolute bioavailability of nolatrexed dihydrochloride in mice was 23.58%. CONCLUSION: The absolute bioavailability of nolatrexed dihydrochloride in mice determined in this study provides an experimental basis for development of the oral preparation of the drug.

[Inhibitory effect of polysaccharides on the six-alpha-helix bundle formation of HIV gp41 protein].

OBJECTIVE: To compare the in vitro inhibitory effect of expolysaccharides from Streptomyces, polysaccharides of Ganoderma lucidum and rice bran on six-alpha-helix bundle formation of HIV gp41 protein. METHODS: The amount of six-alpha-helix bundle formed in the presence of N36 and C34 was tested by ELISA in response to treatments with different doses of polysaccharides. RESULTS: Expolysaccharides from Streptomyces potentially inhibited six-alpha-helix bundle formation with the effective concentration (IC(50)) of 145.48-/+7.25 mg /L. Polysaccharides of Ganoderma lucidum and rice bran showed no effect on the six-alpha-helix bundle formation. CONCLUSION: Expolysaccharides from Streptomyces can inhibit the six-alpha-helix bundle formation of HIV gp41, whereas polysaccharides of Ganoderma lucidum and rice bran do not exhibit such activity.