[The anti-respiratory syncytial virus effect of an active compound (AP3) from a Chinese medicinal herb-Herba patriniae in vitro].
OBJECTIVE
To study the effect on anti-respiratory syncytial virus of an active compound (AP3) from a Chinese medicinal herb-Herba patriniae in vitro.


METHODS
Active component of herba patriniae (AP3) was extracted and its anti-respiratory syncytial virus (RSV) effect was tested. A water soluble substance (AP3) was isolated from a Chinese herb Herba patriniae, by hot water extraction, ethol precipitation and gel permeation column chromatography. The cytotoxicity of AP3 was tested by adding it to HeLa cells directly. Its effect against RSV was estimated by CPEI assay while ribavirin was used as positive control.


RESULTS
Chemical test showed that the nature of substance AP3 was polysaccharide. The median cytotoxic concentration (TC(50)) of AP3 was 11.45 mg/ml by morphological observation and the median effective concentration (50% effective concentration, EC(50)) of it against replication of the long strain of RSV in HeLa cells was 0.0986 mg/ml. The Therapeutic index (TI = TC(50)/EC(50)) of AP3 was 116.12, much higher than the TI of herba patriniae (AP1) (TI = 59.26) and ribavirin (TI = 53.45). Moreover, AP3 gave a dose-dependent response in inhibiting RSV. In the assay, the effect of AP3 against RSV growth was also tested. In addition, the effect of AP3 on virus growth, AP3 inhibited replication of RSV in HeLa cells, when added at 0 h, 2 h, 4 h after virus infection, were also tested.


CONCLUSIONS
This study suggested that the AP3 exerted an obvious inhibitory effect to RSV in HeLa cell culture. This study furnished a reliable evidence for development of a new antiviral drug.
Li
Shan-shan
SS
College of Public Health, Harbin Medical University, Harbin 150001, China.
Li
Hong-yuan
HY
Piao
Ying-ai
YA
Liu
Dian-li
DL
Tian
Wen-jing
WJ
Dong
Yan-mei
YM
D000998:Antiviral Agents / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D006367:HeLa Cells; D006801:Humans; D012136:Respiratory Syncytial Viruses / Q000187:drug effects*; D013997:Time Factors
D000998:Antiviral Agents; D004365:Drugs, Chinese Herbal