Grace Gar-Lee Yue

Evaluation of in vitro anti-proliferative and immunomodulatory activities of compounds isolated from Curcuma longa

The rhizome of Curcuma longa (CL) has been commonly used in Asia as a potential candidate for the treatment of different diseases, including inflammatory disorders and cancers. The present study evaluated the anti-proliferative activities of the isolated compounds (three curcuminoids and two turmerones) from CL, using human cancer cell lines HepG2, MCF-7 and MDA-MB-231. The immunomodulatory activities of turmerones (alpha and aromatic) isolated from CL were also examined using human peripheral blood mononuclear cells (PBMC). Our results showed that the curcuminoids (curcumin, demethoxycurcumin and bisdemethoxycurcumin) and alpha-turmerone significantly inhibited proliferation of cancer cells in dose-dependent manner. The IC(50) values of these compounds in cancer cells ranged from 11.0 to 41.8 microg/ml. alpha-Turmerone induced MDA-MB-231 cells to undergo apoptosis, which was confirmed by annexin-V and propidium iodide staining, and DNA fragmentation assay. The caspase cascade was activated as shown by a significant decrease of procaspases-3, -8 and -9 in alpha-turmerone treated cells. Both alpha-turmerone and aromatic-turmerone showed stimulatory effects on PBMC proliferation and cytokine production. The anti-proliferative effect of alpha-turmerone and immunomodulatory activities of ar-turmerone was shown for the first time. The findings revealed the potential use of CL crude extract (containing curcuminoids and volatile oil including turmerones) as chemopreventive agent.

Immunostimulatory activities of polysaccharide extract isolated from Curcuma longa

Several curcuminoids and sesquiterpenoids isolated from Curcuma longa (CL) have been shown to have many pharmacological activities. In the present study, the immunomodulatory activities of the polar fractions of CL hot water extracts were investigated using human peripheral blood mononuclear cells (PBMC). Our results showed that the high polarity fraction of the hot water extract exhibited stimulatory effects on PBMC proliferation as shown in [methyl-(3)H]-thymidine incorporation assay. In an attempt to isolate the active components responsible for the activities, further partition with ethyl acetate, n-butanol and ethanol, progressively were performed. The cytokine productions (TGF-beta, TNF-alpha, GM-CSF, IL-1alpha, IL-5, IL-6, IL-8, IL-10, IL-13, etc.) have been modulated by a polysaccharide-enriched fraction as shown in ELISA and cytokine protein array. The proportion of CD14 positive stained PBMC was increased by such fraction. The composition of monosaccharide of the active fraction has been determined by GC-MS and gel permeation chromatography. The immunostimulatory effects of C. longa polysaccharides on PBMC were shown for the first time. The findings revealed the potential use of C. longa crude extract (containing curcuminoids and polysaccharides) as an adjuvant supplement for cancer patients, whose immune activities were suppressed during chemotherapies.

Isolation, Structure Characterization, and Immunomodulating Activity of a Hyperbranched Polysaccharide from the Fruiting Bodies of Ganoderma sinense

A polysaccharide (GSP-6B) with a molecular mass of 1.86 × 10⁶ Da was isolated from the fruiting bodies of Ganoderma sinense . Chemical composition analysis, methylation analysis, infrared spectroscopy, and nuclear magnetic resonance spectroscopy were conducted to elucidate its structure. GSP-6B contains a backbone of (1→6)-linked-β-D-glucopyranosyl residues, bearing branches at the O-3 position of every two sugar residues along the backbone. The side chains contain (1→4)-linked-β-D-glucopyranosyl residues, (1→3)-linked-β-D-glucopyranosyl residues, and nonreducing end β-D-glucopyranosyl residues. An in vitro immunomodulating activity assay revealed that GSP-6B could significantly induce the release of IL-1β and TNF-α in human peripheral blood mononuclear cell (PBMC) and showed no toxicity to either PBMC or a human macrophage cell line THP-1. GSP-6B could also activate dendritic cells (DC) by stimulating the secretion of IL-12 and IL-10 from DC.

Anti-angiogenic effect and mechanism of rhein from Rhizoma Rhei.

PURPOSE Rhein is a major bioactive component in rhubarb (Dahuang), a famous traditional Chinese medicine derived from the rhizome of Rheum palmatum and related species. It was reported to have antitumor and anti-inflammatory properties. Our previous studies found rhein displaying potent anti-angiogenic activities in a zebrafish embryo model. Its action mechanisms need further elucidation. METHODS The inhibition effect of vessel formation was checked by microscopic imaging on Tg(fli1a:EGFP)y1 zebrafish embryos. Then the action mechanism of rhein was investigated by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) on wild type zebrafish embryos and further tested on human umbilical vein endothelial cells. RESULTS At 20μM, rhein could almost completely block intersegmental blood vessels formation at both 48 and 72hpf, and completely inhibit subintestinal vessel plexus formation at 72hpf. Rhein affected multiple molecular targets related to angiogenesis, particularly angpt2 and tie2, and also inhibited endothelial cell migration. CONCLUSION Rhein could inhibit angiogenesis, which may play a role in antitumor and anti-inflammatory actions.

Anti-angiogenic effects of the fruit of Alpinia oxyphylla.

AIM OF STUDY The fruit of Alpinia oxyphylla, an herb commonly used in East Asian medicine, is variously used for the treatment of cancer and inflammatory conditions, which may possibly be mediated through anti-angiogenesis. This study aims to check for anti-angiogenic functions in the herb. MATERIALS AND METHODS The 95% ethanol extract and four subsequent fractions (n-hexane, ethyl acetate, n-butanol and aqueous fractions) of the fruit of A. oxyphylla were tested on zebrafish model by quantitative endogenous alkaline phosphatase assay; then the active fractions were further tested on wild type and Tg(fli1a:EGFP)y1 zebrafish embryos and human umbilical vein endothelial cells and tumor cell lines for the anti-angiogenic effects. RESULTS The n-hexane and ethyl acetate fractions showed anti-angiogenic potentials in both in vivo and in vitro models. CONCLUSIONS The use of A. oxyphylla for cancer and inflammation diseases may be partly due to its effects against vessel formation.

Effects of Cordyceps sinensis, Cordyceps militaris and their isolated compounds on ion transport in Calu-3 human airway epithelial cells

AIM OF THE STUDY The traditional Chinese medicine Cordyceps sinensis (CS) (Clavicipitaceae) improves pulmonary function and is used to treat respiratory disease. Here, we compare the efficacy and mechanisms of action of Cordyceps sinensis and Cordyceps militaris (CM) (Clavicipitaceae) in Calu-3 human airway epithelial monolayer model. MATERIAL AND METHODS The extracts of Cordyceps sinensis and Cordyceps militaris, as well as their isolated compounds, cordycepin and adenosine, stimulated ion transport in a dose-dependent manner in Calu-3 monolayers. In subsequent experiments, transport inhibitor bumetanide and carbonic anhydrase inhibitor acetazolamide were added after Cordyceps sinensis and Cordyceps militaris extracts to determine their effects on Cl- and HCO3- movement. RESULTS The results suggested that Cordyceps sinensis and Cordyceps militaris extracts may affect the anion movement from the basolateral to apical compartments in the airway epithelia. CONCLUSIONS Basolateral Na+-K+-2Cl- cotransporter and apical cAMP-dependent cystic fibrosis transmembrane conductance regulator Cl- channel are involved in the process. The results provide the first evidence for the pharmacological mechanism of Cordyceps sinensis and Cordyceps militaris on respiratory tract.

Cyclopeptide RA-V inhibits angiogenesis by down-regulating ERK1/2 phosphorylation in HUVEC and HMEC-1 endothelial cells

BACKGROUND AND PURPOSE Anti‐angiogenic agents have recently become one of the major adjuvants for cancer therapy. A cyclopeptide, RA‐V, has been shown to have anti‐tumour activities. Its in vitro anti‐angiogenic activities were evaluated in the present study, and the underlying mechanisms were also assessed.

Green tea (Camellia sinensis) extract inhibits both the metastasis and osteolytic components of mammary cancer 4T1 lesions in mice

Green tea (Camellia sinensis, CS), a kind of Chinese tea commonly consumed as a healthy beverage, has been demonstrated to have various biological activities, including antioxidation, antiobesity and anticancer. Our study aims to investigate the antitumor, antimetastasis and antiosteolytic effects of CS aqueous extract both in vitro and in vivo using metastasis-specific mouse mammary carcinoma 4T1 cells. Our results showed that treatment of 4T1 cells with CS aqueous extract resulted in significant inhibition of 4T1 cell proliferation. CS extract induced 4T1 apoptosis in a dose-dependent manner as assessed by annexin-V and propidium iodide staining and caspase-3 activity. Western blot analysis showed that CS increased the expression of Bax-to-Bcl-2 ratio and activated caspase-8 and caspase-3 to induce apoptosis. CS also inhibited 4T1 cell migration and invasion at 0.06-0.125 mg/ml. In addition, CS extract (0.6 g/kg, orally fed daily for 4 weeks) was effective in decreasing the tumor weight by 34.8% in female BALB/c mice against water treatment control (100%). Apart from the antitumor effect, CS extract significantly decreased lung and liver metastasis in BALB/c mice bearing 4T1 tumors by 54.5% and 72.6%, respectively. Furthermore, micro-computed tomography and in vitro osteoclast staining analysis suggested that CS extract was effective in bone protection against breast cancer-induced bone destruction. In conclusion, the present study demonstrated that the CS aqueous extract, which closely mimics green tea beverage, has potent antitumor and antimetastasis effects in breast cancer and could protect the bone from breast cancer-induced bone destruction.

Comparative Studies on the Immunomodulatory and Antitumor Activities of the Different Parts of Fruiting Body of Ganoderma lucidum and Ganoderma Spores

Ganoderma lucidum (GL, Lingzhi) has been suggested as a candidate for immunomodulation and cancer treatment. The present study aimed at comparing the different parts of the fruiting body (whole fruiting body, pileus and stipe) of GL as well as Ganoderma spores (sporoderm‐broken and ‐unbroken), with regard to their antitumor and immunomodulatory activities in S‐180 sarcoma‐bearing mice. The hot water extracts of different parts of GL or the Ganoderma spores were orally administered to the sarcoma‐bearing mice. The results showed that GL whole fruiting body, stipe and sporoderm‐broken spore possessed stronger inhibitory activities on sarcoma growth when compared with the pileus extract. Higher immunomodulatory activities in terms of enhancing the proliferative responses and the cytokines (IFN‐γ, IL‐4 and IL‐6) production of spleen lymphocytes were also found in GL stipe and sporoderm‐broken spore treatment groups. The sporoderm‐broken spores had higher stimulatory effects on mitogen‐activated spleen lymphocytes of healthy mice than those of sarcoma‐bearing mice. In addition, the immunostimulatory activities of GL hot water extracts and Ganoderma spores were shown to be comparable; hence the latter did not show superiority in efficacy. This is the first comparative study on the immunomodulatory activities of Ganoderma spores and the fruiting body extracts. Copyright

The Role of Turmerones on Curcumin Transportation and P-Glycoprotein Activities in Intestinal Caco-2 Cells

The rhizome of Curcuma longa (turmeric) is often used in Asia as a spice and as a medicine. Its most well-studied component, curcumin, has been shown to exhibit poor bioavailability in animal studies and clinical trials. We hypothesized that the presence of lipophilic components (e.g., turmerones) in turmeric extract would affect the absorption of curcumin. The effects of turmerones on curcumin transport were evaluated in human intestinal epithelial Caco-2 cells. The roles of turmerones on P-glycoprotein (P-gp) activities and mRNA expression were also evaluated. Results showed that in the presence of α- and aromatic turmerones, the amount of curcumin transported into the Caco-2 cells in 2 hours was significantly increased. α-Turmerone and verapamil (a P-gp inhibitor) significantly inhibited the efflux of rhodamine-123 and digoxin (i.e., inhibited the activity of P-gp). It is interesting that aromatic turmerone significantly increased the rhodamine-123 efflux and P-gp (MDR1 gene) mRNA expression levels. The effects of α- and aromatic turmerones on curcumin transport as well as P-gp activities were shown here for the first time. The presence of turmerones did affect the absorption of curcumin in vitro. These findings suggest the potential use of turmeric extract (including curcumin and turmerones), rather than curcumin alone, for treating diseases.