ABSTRACT
To explore the antibacterial activity and mechanism of total alkaloids and berberine from Coptidis Rhizoma on Aeromonas hydrophila, and determine the effect of total alkaloids and berberine from Coptidis Rhizoma on minimum inhibitory concentrations, permeability and fluidity of cell membrane, conformation of membrane proteins and virulence factors of A. hydrophila. The results showed that both total alkaloids and berberine from Coptidis Rhizoma had antibacterial activities on A. hydrophila, with minimum inhibitory concentrations of 62.5 and 125 mg · L(-1), respectively. Total alkaloids and berberine from Coptidis Rhizoma could increase the fluidity of membrane, change the conformation of membrane porteins and increase the permeability of bacteria membrane by 24.52% and 19.66%, respectively. Besides, total alkaloids and berberine from Coptidis Rhizoma significantly decreased the hemolysis of exotoxin and the mRNA expressions of aerA and hlyA (P < 0.05, P < 0.01), the secretion of endotoxin and the mRNA expression of LpxC (P < 0.05, P < 0.01). The results suggested that the antibacterial activity of total alkaloids and berberine from Coptidis Rhizoma on A. hydrophila may be related to the bacteria membrane injury. They inhibited the bacterial growth by increasing membrane lipid fluidity and changing conformation of membrane proteins, and reduced the secretion of virulence factors of A. hydrophila to weaken the pathogenicity.
Subject(s)
Aeromonas hydrophila , Genetics , Metabolism , Alkaloids , Pharmacology , Anti-Bacterial Agents , Pharmacology , Bacterial Proteins , Genetics , Metabolism , Bacterial Toxins , Berberine , Pharmacology , Cell Membrane , Genetics , Metabolism , Coptis , Chemistry , Drugs, Chinese Herbal , Pharmacology , Membrane Fluidity , Rhizome , ChemistryABSTRACT
The concentrations of berberine (BBR) and 8-cetylberberine (8-BBR-C16) in rat plasma and tissue were determined by RP-HPLC. Both the plasma pharmacokinetics characteristic and tissue distribution differences of BBR and 8-BBR-C16 were compared to provide experimental data for the mechanism research and further drug development. After the oral administrations of BBR and 8-BBR-C16 at the dose of 80 mg x kg(-1) for rats, the pharmacokinetics result showed that compared with BBR, the C(max) and AUC(0-t), of 8-BBR-C16 increased by 2.8 times and 12.9 times respectively, t1/2 extended from 3.61 h to 11.90 h. The tissue distribution result showed that compared with BBR, the concentration of 8-BBR-C16 in various organizations increased and the retention time extended remarkably. The maximum concentration was achieved in lung and the highest concentration in it was 3 731.82 ng x g(-1). After being derived, the C(max) in plasma and bioavailability of 8-BBR-C16 increased remarkably and the circulation time in vivo extended. The drug concentration in tissue increased remarkably, and the distribution ratio changed too, with strong targeting selection in lung.