Assessment of the anti-herpes simplex virus type 1 activity of a water extract from Cinnamon / 中华实验和临床病毒学杂志

Objective@#To evaluate the anti- herpes simplex virus type 1 (HSV-1) activity of KPC-rg1, a water extract from Cinnamomum cassia, and explore its potential function of broad-spectrum antivirus effect.@*Methods@#In vitro, the changes of morphology of Vero cells were assessed and viral loads were detected after cells were infected with HSV-1 alone and HSV-1 pre-treated with KPC-rg1 respectively. The corneal lesions of mouse and tree shrew corneal infection model were evaluated after they were infected with HSV-1 alone and HSV-1 pre-treated with KPC-rg1 respectively. The antiviral activity of KPC-rg1 against 9 viruses were measured by CPE and GFP reduction assays.@*Results@#The virus replication of HSV-1 infected cells was moderately inhibited by KPC-rg1 in a dose range of 0.0001-1.0 mg/ml, while the cells were completely protected when they were infected with HSV-1 pre-treated with KPC-rg1 (0.001-1.0 mg/ml). The corneal lesions of animals were improved in both mouse and tree shrews models infected with HSV-1 after the treatment of KPC-rg1, while animals were completely protected from infection when HSV-1 pre-treated with KPC-rg1. KPC-rg1 had a potential anti-virus effect on the enveloped viruses such as HSV-1, HCMV, RSV alone and HIV-1.@*Conclusions@#KPC-rg1 is a collosol (Tyndall effect) which would immediately form a stable super-nanoparticle structure of KPC-rg1/virus when encounter virus, and thus the virus coated by KPC-rg1 lost its ability of infection. KPC-rg1 can reduce the suffering by newly or latent virus infection because its encapsulation of virus and inhibition of further infection. Our study added additional proofs of the anti-viral property of the water extract from Cinnamomum cassia, and provided a further basis to develop KPC-rg1 as a drug which could be potentially applied in clinic to treat HSV-1 infection.

Preparation and evaluation of sustained-release solid dispersions co-loading gastrodin with borneol as an oral brain-targeting enhancer

Borneol is a traditional Chinese medicine that can promote drug absorption from the gastrointestinal tract and distribution to the brain. However, stomach irritation may occur when high doses of borneol are used. In the present work, gastrodin, the main bioactive ingredient of the traditional Chinese drug "Tianma" (Rhizoma Gastrodiae) was used as a model drug to explore reasonable application of borneol. Sustained-release solid dispersions (SRSDs) for co-loading gastrodin and borneol were prepared using ethylcellulose as a sustained release matrix and hydroxy-propyl methylcellulose as a retarder. The dispersion state of drug within the SRSDs was analyzed by using scanning electron microscopy, differential scanning calorimetry, and powder X-ray diffractometry. The results indicated that both gastrodin and borneol were molecularly dispersed in an amorphous form. Assay of in vitro drug release demonstrated that the dissolution profiles of gastrodin and borneol from the SRSDs both fitted the Higuchi model. Subsequently, gastric mucosa irritation and the brain targeting of the SRSDs were evaluated. Compared with the free mixture of gastrodin and borneol, brain targeting of SRSDs was slightly weaker (brain targeting index: 1.83 vs. 2.09), but stomach irritation obviously reduced. Sustained-release technology can be used to reduce stomach irritation caused by borneol while preserving sufficient transport capacity for oral brain-targeting drug delivery.

Cell growth and alkaloid synthesis in suspension cultures of Datura metel / 中草药

Object To investigate the synthesis of alkaloids by cell suspension cultures of Datura metel L. Methods Cultured cells derived from leaves of D. metel were m aintained in Murashige and Skoog (MS) liquid medium. The effects of different c arbohydrated, different inoculum sizes, and different pH values of medium as aff ecting facters on cell growth and alkaloid formation were studied. Re sults The optimum carbohydrate was sucrose, inoculum size (1.5 - 2. 0 g/L) for fresh weight and initial pH values (5.5-6.0) of the medium were benefit for cell growth and alkaloid synthesis in the suspension cultures. The synthesis of alk aloids was improved when exogenous phenylalanine added to the culture. Conclusion Suspension-cultured cells of D. metel c an be used to synthesize alkaloids.

Pharmacokinetics of gastrodigenin in brain tissue of mice after intragastric administration of gastrodin / 中草药

Objective To establish an HPLC method for determination of gastrodigenin concentration in brain tissue of mice and investigate its pharmacokinetics after intragastric administration of gastrodin.Methods The brain homogenate was extracted with acetoacetate and analyzed by HPLC method.The separation was performed on a Diamonsil C18 column(250 mm ? 4.6 mm,5 ?m) under the following chromatographic conditions: mobile phase,acetonitrile-water(10.5∶89.5);column temperature,25 ℃;flow rate,1.0 mL/min;detection wavelength,221 nm;and sampling amount,20 ?L.Results The calibration curve showed good linearity within the concentration range of 50-1 616 ng/mL(r= 0.999 6).The relative recoveries were 93.8%-95.1%,and the RSDs of the intra-and inter-day precision were less than 10%.The concentration-time profile of gastrodigenin in brain tissue of mice showed double peaks(tmax1=15 min,tmax2=90 min).The AUC was 52 822.5 ng?min/g,and t1/2(ke) was 54.8 min.Conclusion The analytical method established for assay of gastrodigenin in brain tissue of mice is sensitive and accurate.The result indicates that gastrodin could rapidly distribute to the brain,be metabolized into gastrodigenin,and be eliminated after oral administration.