A synergy interaction of artocarpin and tetracycline against Pseudomonas aeruginosa and its mechanism of action on membrane permeability.

The emergence of antibacterial resistance has significantly increased. Pseudomonas aeruginosa is associated with nosocomial infection and difficult to control. Artocarpin, a flavonoid from Artocarpus heterophyllus Lam. exhibits several pharmacological properties including antibacterial. The study was performed to evaluate interaction between artocarpin and antibiotics including tetracycline against P. aeruginosa. Its mechanism of action on membrane permeability was also investigated. Broth microdilution was conducted for the susceptibility assay. The interaction of artocarpin and antibiotics was evaluated using checkerboard method, the effect on alteration of membrane cell was investigated using bacteriolysis and the released of 260 nm materials. Artocarpin showed moderate to weak activity against the Gram-negative bacteria including P. aeruginosa with MIC values in the range of 31.25-250 µg/mL. A synergistic effect against P. aeruginosa was produced by the combination of artocarpin (31.25 µg/mL) and tetracycline (1.95 µg/mL) with FICI of 0.37. The time-killing assay showed that artocarpin enhance the antibacterial activity of tetracycline against P. aeruginosa by completely inhibiting the bacterial growth. Additionally, the mixture of artocarpin (31.25 µg/mL) and tetracycline (1.95 µg/mL) disrupted membrane permeability and lead to cell death. These results proposed that the combination of artocarpin and tetracycline may be used to overcome P. aeruginosa infection.

Investigation of HIV-1 Viral Protein R Inhibitory Activities of Twelve Thai Medicinal Plants and Their Commercially Available Major Constituents.

Viral protein R (Vpr) is an accessory protein in Human immunodeficiency virus-1 (HIV-1) and has been suggested as an attractive target for HIV disease treatment. Investigations of the ethanolic extracts of twelve Thai herbs revealed that the extracts of the Punica granatum fruits, the Centella asiatica aerials, the Citrus hystrix fruit peels, the Caesalpinia sappan heartwoods, the Piper betel leaves, the Alpinia galangal rhizomes, the Senna tora seeds, the Zingiber cassumunar rhizomes, the Rhinacanthus nasutus leaves, and the Plumbago indica roots exhibited the anti-Vpr activity in HeLa cells harboring the TREx plasmid encoding full-length Vpr (TREx-HeLa-Vpr cells). Moreover, the investigation of the selected main constituents in Punica granatum, Centella asiatica, A. galangal, and Caesalpinia sappan indicated that punicalagin, asiaticoside, ellagic acid, madecassic acid, madecassoside, zingerone, brazilin, and asiatic acid possessed anti-Vpr activities at the 10 µM concentration. Among the tested extracts and compounds, the extracts from Centella asiatica and Citrus hystrix and the compounds, punicalagin and asiaticoside, showed the most potent anti-Vpr activities without any cytotoxicity, respectively.

Tiliacora triandra extract and its major constituent attenuates diabetic kidney and testicular impairment by modulating redox imbalance and pro-inflammatory responses in rats.

BACKGROUND: Literature has demonstrated that diabetes is associated with renal complication and testicular dysfunctions. The current study explored the potential of Tiliacora triandra extract and its major component against diabetic kidney and testicular damages in rats. METHODS: Diabetes was induced by high fat diet/streptozotocin (HFD/STZ) and treated orally with Tiliacora triandra extract (TTE, 100 and 400 mg kg-1 body weight) and its major component, 5,7-dihydroxy-6-oxoheptadecanoic acid (DHA, 25 mg kg-1 body weight) for 30 consecutive days. Testicular activities of testicular enzymes, serum levels of testosterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), sperm parameters and urinalysis for protein and albumin levels were evaluated. Renal and testicular biomarkers of oxidative stress and pro-inflammation were analysed along with histology. RESULTS: The experimental diabetes induced significant alterations in the levels and activities of indices evaluated compared to non-diabetic normal rats. The 28-day treatment of diabetic rats with TTE and DHA markedly improved activities of testicular enzymes, restored levels of testosterone, LH and FSH and sperm parameters compared to untreated diabetic rats. TTE and DHA abrogated proteinuria and reversed urine albumin level. Testicular and renal oxidative stress and pro-inflammation were attenuated in diabetic rats treated with TTE and DHA. The diabetes-mediated histopathological damage was alleviated in the kidney and testis. CONCLUSION: The protective effect of TTE and DHA against diabetes induced kidney and testicular damages may be related to its antioxidant and anti-inflammatory activities. © 2020 Society of Chemical Industry.

Selection of Reference Genes for Expression Analysis in Chinese Medicinal Herb Huperzia serrata.

Huperzine A (HupA) is a powerful and selective inhibitor of acetylcholinesterase. It has attracted widespread attention endangering the ultimate plant sources of Lycopodiaceae family. In this study, we used Huperzia serrata, extensively used in Traditional Chinese medicine (TCM), a slow growing vascular plant as the model plant of the Lycopodiaceae family to develop and validate the reference genes. We aim to use gene expression platform to understand the gene expression of different tissues and developmental stages of this medicinal herb. Eight candidate reference genes were selected based on RNA-seq data and evaluated with qRT-PCR. The expression of L/ODC and cytochrome P450s genes known for their involvement in lycopodium alkaloid biosynthesis, were also studied to validate the selected reference genes. The most stable genes were TBP, GAPDH, and their combination (TBP + GAPDH). We report for the first time the reference gene of H. serrata's different tissues which would provide important insights into understanding their biological functions comparing other Lycopodiaceae plants and facilitate a good biopharming approach.