Procyanidins and butanol extract of Cinnamomi Cortex inhibit SARS-CoV infection.
We found that the butanol fraction of Cinnamomi Cortex (CC/Fr.2) showed moderate inhibitory activity in wild-type severe acute respiratory syndrome coronavirus (wtSARS-CoV) and HIV/SARS-CoV S pseudovirus infections. The inhibition on pseudovirus was also seen in cells pretreated with the CC and CC/Fr.2 (IC(50S), 283.4+/-16.3 and 149.5+/-13.5 microg/ml, respectively), however the highest activities on wtSARS-CoV were observed when the viruses were treated by the extracts before challenging (IC(50S), 43.1+/-2.8 and 7.8+/-0.3 microg/ml; SIs, 8.4 and 23.1, respectively). Among the compounds fractionated from CC, procyanidin A2 and procyanidin B1 showed moderate anti-wtSARS-CoV activity (IC(50S), 29.9+/-3.3 and 41.3+/-3.4 microM; SIs, 37.35 and 15.69, respectively). We also sought to determine whether they could interfere with the clathrin-dependent endocytosis pathway using transferrin receptor (TfR) as an indicator. CC/Fr.2 inhibited the internalization of TfR but the procyanidins did not. Taken together, CC/Fr.2 contains unknown substances, that could inhibit the infection, probably by interfering with endocytosis, and it also contains procyanidins that did not inhibit the internalization but inhibited the infection. Therefore, CC extracts contain anti-virus activities that act through distinct mechanisms according to differences in the compounds or mixtures.
Division of Emerging Infectious Diseases, Department of Internal Medicine, Tohoku University, 980-8574, Japan.
Min
M
Zhuang
Hong
H
Jiang
Yasuhiro
Y
Suzuki
Xiaoguang
X
Li
Peng
P
Xiao
Takashi
T
Tanaka
Hong
H
Ling
Baofeng
B
Yang
Hiroki
H
Saitoh
Lianfeng
L
Zhang
Chuan
C
Qin
Kazuo
K
Sugamura
Toshio
T
Hattori
D000440:Butanols / Q000737:chemistry; D002460:Cell Line; D002935:Cinnamomum zeylanicum; D015536:Down-Regulation; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D010946:Plants, Medicinal / Q000737:chemistry*; D044945:Proanthocyanidins / Q000737:chemistry / Q000494:pharmacology*; D045473:Severe acute respiratory syndrome-related coronavirus / Q000187:drug effects / Q000502:physiology*; D045169:Severe Acute Respiratory Syndrome / Q000188:drug therapy / Q000821:virology*
D000440:Butanols; D004365:Drugs, Chinese Herbal; D044945:Proanthocyanidins; C532132:cinnamomi cortex