J.K.H. Cheung

A polysaccharide isolated from Cordyceps sinensis, a traditional Chinese medicine, protects PC12 cells against hydrogen peroxide-induced injury

Cordyceps sinensis, a well-known traditional Chinese medicine, possesses activities in anti-tumour, anti-oxidation and stimulating the immune system; however, the identity of active component(s) is not determined. By using anti-oxidation activity-guided fractionation, a polysaccharide of molecular weight approximately 210 kDa was isolated from cultured Cordyceps mycelia by ion-exchange and sizing chromatography. The isolated polysaccharide, having strong anti-oxidation activity, contains glucose, mannose and galactose in a ratio of 1 : 0.6 : 0.75. The pre-treatment of isolated polysaccharide on the cultured rat pheochromocytoma PC12 cells shows strong protective effect against hydrogen peroxide (H(2)O(2))-induced insult. Treatment of the cells with the isolated polysaccharide at 100 microg/ml prior to H(2)O(2) exposure significantly elevated the survival of PC12 cells in culture by over 60%. In parallel, the H(2)O(2)-induced production of malondialdehyde in cultured cells was markedly reduced by the polysaccharide treatment. Moreover, the pre-treatment of the isolated polysaccharide significantly attenuated the changes of glutathione peroxidase and superoxide dismutase activities in H(2)O(2)-treated cells in a dose-dependent manner. This is the first report in identifying a polysaccharide from Cordyceps, which protects against the free radical-induced neuronal cell toxicity.

Cordysinocan, a polysaccharide isolated from cultured Cordyceps, activates immune responses in cultured T-lymphocytes and macrophages: signaling cascade and induction of cytokines.

Cordyceps sinensis, a well-known traditional Chinese medicine, possesses activities in anti-tumor, anti-oxidation and stimulating the immune response; however, the identity of active component(s) is not determined. A strain of Cordyceps sinensis, namely UST 2000, has been isolated. By using activity-guided purification, a novel polysaccharide of molecular weight approximately 82 kDa was isolated from the conditioned medium of cultured Cordyceps. The isolated exo-polysaccharide, namely cordysinocan, contains glucose, mannose, galactose in a ratio of 2.4:2:1. In cultured T-lymphocytes, application of cordysinocan induced the cell proliferation and the secretion of interleukin-2, interleukin-6 and interleukin-8. In addition, the phosphorylation of extracellular signal-regulated kinases (ERK) was induced transiently by the treatment of cordysinocan. Moreover, application of cordysinocan in cultured macrophages increased the phagocytosis activity and the enzymatic activity of acid phosphatase. These results therefore verify the important role of Cordyceps polysaccharide in triggering such immune responses.

Danggui Buxue Tang – A Chinese herbal decoction activates the phosphorylations of extracellular signal‐regulated kinase and estrogen receptor α in cultured MCF‐7 cells

Danggui Buxue Tang (DBT), a Chinese herbal decoction used to treat ailments in women, contains Radix Astragali (Huangqi; RA) and Radix Angelicae Sinensis (Danggui; RAS). The weight ratio of RA to RAS used in DBT must be 5:1 as stipulated as early as AD 1247; however, DBTs mechanism of action has never been described. Here, the estrogenic effects of DBT were investigated by determining the phosphorylations of estrogen receptor α (ERα) and extracellular signal‐regulated kinase 1/2 (Erk1/2) in cultured MCF‐7 cells. The application of DBT triggered the phosphorylation of ERα and Erk1/2 in a time‐dependent manner. In contrast to the effect of estrogen, DBT triggered ERα phosphorylation at both S118 and S167. This DBT‐specific phosphorylation was not triggered by an extract of one of the individual herbs, or by mixing the extracts of RA and RAS. DBT‐induced downstream signals are described here. These signals suggest the uniqueness of this Chinese herbal decoction that requires a well‐defined formulation.

A Chinese Herbal Decoction, Danggui Buxue Tang, Stimulates Proliferation, Differentiation and Gene Expression of Cultured Osteosarcoma Cells: Genomic Approach to Reveal Specific Gene Activation

Danggui Buxue Tang (DBT), a Chinese herbal decoction used to treat ailments in women, contains Radix Astragali (Huangqi; RA) and Radix Angelicae Sinensis (Danggui; RAS). When DBT was applied onto cultured MG-63 cells, an increase of cell proliferation and differentiation of MG-63 cell were revealed: both of these effects were significantly higher in DBT than RA or RAS extract. To search for the biological markers that are specifically regulated by DBT, DNA microarray was used to reveal the gene expression profiling of DBT in MG-63 cells as compared to that of RA- or RAS-treated cells. Amongst 883 DBT-regulated genes, 403 of them are specifically regulated by DBT treatment, including CCL-2, CCL-7, CCL-8, and galectin-9. The signaling cascade of this DBT-regulated gene expression was also elucidated in cultured MG-63 cells. The current results reveal the potential usage of this herbal decoction in treating osteoporosis and suggest the uniqueness of Chinese herbal decoction that requires a well-defined formulation. The DBT-regulated genes in the culture could serve as biological responsive markers for quality assurance of the herbal preparation.

A chinese herbal decoction prepared from radix astragali and radix angelicae sinensis induces the expression of erythropoietin in cultured Hep3B cells

Danggui Buxue Tang (DBT), a Chinese medicinal decoction used commonly for treating womens ailments, contains Radix Astragali (RA) and Radix Angelicae Sinensis (RAS). According to Chinese medicinal theory, this decoction is to nourish the blood function; this, however, has not been demonstrated on the molecular level. In order to reveal the hematopoietic effect of this decoction, DBT was applied to cultured Hep3B human hepatocellular carcinoma cells. The treatment of DBT induced mRNA expression of erythropoietin (EPO) in a dose-dependent manner and peaked at approximately 2.5-fold induction. The secreted EPO in cultured Hep3B cells was quantified by ELISA: the treatment of DBT potentiated the effect of hypoxia-induced EPO expression in the cultured cells. In addition, the DBT-induced EPO expression could be abolished by pre-treatment with U0126, a mitogen-activated kinase inhibitor. The current results verified the hematopoietic function of this ancient herbal decoction.

A Chinese herbal decoction, Danggui Buxue Tang, activates extracellular signal-regulated kinase in cultured T-lymphocytes.

Danggui Buxue Tang (DBT) is prepared from Radix Astragali and Radix Angelicae Sinensis. This Chinese herbal decoction has been shown to stimulate the proliferation of T‐lymphocytes; however, the action mechanism of this stimulation has not been revealed. In cultured T‐lymphocytes, application of DBT markedly induced the cell proliferation, the release of interleukin‐2, ‐6 and ‐10, as well as the phosphorylation of extracellular signal‐regulated kinases (ERK). The pre‐treatment of ERK inhibitor blocked the DBT‐induced immune responses. In addition, the polysaccharide‐enriched fraction of DBT showed marked responses on the cultured T‐lymphocytes suggesting the important role of DBT polysaccharide in triggering such immune responses.

Authentication and quality control of Cordyceps sinensis, a traditional Chinese medicine known as winter-worm summer-grass

Introduction Cordyceps sinensis is the complex of fungus Cordyceps sinensis (Berk.) Sacc. (Clavicipitaceae) growing on the larva of Hepialus armoricanus Oberthur (caterpillar) that lives afew inches underground. It is also commonly known as Cordyceps, or “Dong Chong Xia Cao” (winter-worm and summer-grass) in Chinese, because of its appearance during different seasons. Cordyceps has been used in China as a medication for over a few hundred years. In Chinese medicinal theory, Cordyceps processes both “Yin-nourishing” and “Yang-invigorating” activities. Indeed, numerous reports have shown the pharmacological properties of Cordyceps. Different therapeutic effects of Cordyceps have been reported : stimulating immune response; inhibiting cancer growth; protecting the kidney and liver; stimulate cardiovascular circulation; lowering blood glucose; and acting against free-radical formation. Today, Cordyceps is commonly used in many hospitals in China and as a household remedy. However, more than 100 different types of Cordyceps or its substitutes have been found worldwide today. The authentication of Cordycepsis a serious problem on the market.

Surveillance of drug abuse in Hong Kong by hair analysis using LC-MS/MS

The aim of this study is to reveal the habits of drug abusers in hair samples from drug rehabilitation units in Hong Kong. With the application of liquid chromatography-tandem mass spectrometry (LC-MS/MS) technology, a total of 1771 hair samples were analyzed during the period of hair testing service (January 2012 to March 2016) provided to 14 drug rehabilitation units including non-governmental organizations (NGOs), rehabilitation centers, and medical clinics. Hair samples were analyzed for abused drugs and their metabolites simultaneously, including ketamine, norketamine, cocaine, benzoylecgonine, cocaethylene, norcocaine, codeine, MDMA, MDA, MDEA, amphetamine, methamphetamine, morphine, 6-acetylmorphine, phencyclidine, and methadone. The results showed that ketamine (77.2%), cocaine (21.3%), and methamphetamine (16.5%) were the frequently detected drugs among those drug abusers, which is consistent with the reported data. In addition, the usage of multiple drugs was also observed in the hair samples. About 29% of drug-positive samples were detected with multiple drug use. Our studies prove that our locally developed hair drug-testing method and service can be a valid tool to monitor the use of abused drugs, and which could facilitate rehabilitation program management.