Antimetastatic potential of N-acetylcysteine on human prostate cancer cells.

OBJECTIVE: N-acetylcysteine (NAC), is one of the cheapest, safest and widely used over-the-counter-drugs in Thailand. Here the authors examine the antimetastatic potential of NAC on the metastasis of human prostate cancer cells. MATERIAL AND METHOD: Cytotoxicity of NAC to human prostate cancer cells, DU145 and PC3, were determined by proliferation assay using the 3-(4, 5-dimethylthiazol, 2-yl)-2, 5-diphenyltetrazolium bromide (MTT) reagent. Cell migration and invasion were assessed by using a chemotaxis chamber containing membrane pre-coated with collagen IV and Matrigel, respectively. Cell attachment onto the surface of the membrane coated with collagen IV was tested for its adhesion potentiality. RESULTS: NAC could inhibit the growth of DU145 and PC3 cells. Suppression of migration and invasion of both human prostrate cancer cells were observed. Cell attachment to the collagen IV-coated surface was obviously reduced. All inhibitions occurred in a dose-dependent fashion in both cell lines. CONCLUSION: NAC could have a high potential in attenuating the migration of the human prostate cancer cells from their primary site and their adhesion and invasion to the remote locations. Hence, NAC might suppress the growth of the primary and the secondary tumors. Our findings suggest that NAC had a high possibility to become an antimetastatic agent for testing in clinical trials. Then, NAC might be used clinically as an optional adjuvant therapeutic drug in addition to the conventional standard treatment of human prostate cancer, obtaining a better outcome with the least toxic and affordable substance.

Selective Cytotoxicity of Kaempferia parviflora Extracts in Human Cell Lines.

OBJECTIVE: Aims of this study were to (1) compare anti-proliferative activity between aqueous and ethanol Kaempferia parviflora (KP) extracts in both cancer (Human urinary bladder cancer cell, T24) and normal cell lines (Human umbilical vein endothelial cell, HUVEC). (2) confirm selective cytotoxicity of ethanol KP extract to normal and different cancer cell lines (3) investigate its cellular mechanism through p53 and SIRT1 gene expression. METHODS: Phytochemical difference between aqueous and ethanol extract was determined by thin layer chromatography (TLC). Screening for cytotoxic activity in human cell lines was performed by cell viability assay using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reagent. P53 and SIRT1 gene expression were quantified using RT-PCR. RESULTS: Results from the cell viability assay were shown as follows: (1) ethanol extract possessed higher toxicity to cancerous cells than aqueous extract (2) ethanol extract exhibited higher cytotoxicity to cancerous cells than normal cells (3) ethanol extract also showed cytotoxicity, with different levels, to three prostate cancer cell lines varying in aggressiveness. (4) ethanol KP extract induced cell death in T24 via p53 gene expression and prolonged cell survival in HUVEC through SIRT1 gene expression. CONCLUSION: These findings implied that ethanol KP extract might possibly be an alternative for cancer adjuvant therapy through the mechanism of selective p53 and SIRT1 gene expression.

Phytochemical and antioxidant studies of Laurera benguelensis growing in Thailand.

The aim of this study was to investigate metabolites of the lichen Laurera benguelensis. A high-performance liquid chromatographic (HPLC) method has been developed for the characterization of xanthones and anthraquinones in extracts of this lichen. Lichexanthone, secalonic acid D, norlichexanthon, parietin, emodin, teloschistin and citreorosein were detected in the lichen samples, which were collected from two places in Thailand. Components of the lichen were identified by relative retention time and spectral data. This is the first time that a detailed phytochemical analysis of the lichen L. benguelensis was reported and this paper has chemotaxonomic significance because very little has been published on the secondary metabolites present in Laurera species. Some of the metabolites were detected for the first time in the family Trypetheliaceae. The results of preliminary testing of benzene extract and its chloroform and methanol fractions showed that all samples showed a weak radical scavenging activity. The chloroform extract showed the highest antioxidant activity.

Free radical scavenging and anti-acne activities of mangosteen fruit rind extracts prepared by different extraction methods.

The ethanol extracts of mangosteen fruit rinds prepared by several extraction methods were examined for their contents of bioactive compounds, DPPH-scavenging activity, and anti-acne producing bacteria against Propionibacterium acnes and Staphylococcus epidermidis. The dried powder of the fruit rind was extracted with 95% ethanol by maceration, percolation, Soxhlet extraction, ultrasonic extraction, and extraction using a magnetic stirrer. Soxhlet extraction promoted the maximum contents of crude extract (26.60% dry weight) and alpha-mangostin (13.51%, w/w of crude extract), and also gave the highest anti-acne activity with MIC 7.81 and 15.63 microg/mL and MBC 15.53 and 31.25 microg/mL against P. acnes and S. epidermidis, respectively. Ethanol 70% and 50% (v/v) were also compared in Soxhlet extraction. Ethanol 50% promoted the extract with maximum amounts of total phenolic compounds (26.96 g gallic acid equivalents/100 g extract) and total tannins (46.83 g tannic acid equivalents/100 g extract), and also exhibited the most effective DPPH-scavenging activity (EC(50) 12.84 microg/mL). Considering various factors involved in the process, Soxhlet extraction carried a low cost in terms of reagents and extraction time. It appears to be the recommended extraction method for mangosteen fruit rind. Ethanol 50% should be the appropriate solvent for extracting free radical-scavenging components, phenolic compounds, and tannins, while 95% ethanol is recommended for extraction of alpha-mangostin, a major anti-acne component from this plant.

N-acetylcysteine inhibits proliferation, adhesion, migration and invasion of human bladder cancer cells.

OBJECTIVE: Bladder cancer is not only a major public health and economically burden for the patients but also a major clinical impact for Thai urologists. The authors' aim was to study the anti-metastatic effect of N-acetylcysteine (NAC), one of the cheap, safe and widely used over-the-counter-drugs in Thailand, on the human bladder cancer cells. MATERIAL AND METHOD: Effects of NAC at various concentrations on the growth, adhesion, migration, and invasion of the human bladder cancer cell line were assessed in vitro. RESULTS: NAC at the concentrations of 5, 10, 20 and 30 mM could directly and significantly inhibit the growth, adhesion, migration, and invasion of the human bladder cancer cells in a dose-dependent manner The 50% inhibitory concentration (IC50) value for cell viability was 33.33 +/- 0.78 mM. The inhibitory effects on migration, invasion and adhesion properties of the cancer cells were dramatically observed at the concentrations of > or = 10, > or = 20 and > or = 30 mM respectively. CONCLUSION: NAC has an anti-metastatic effect on the human bladder cancer cells by inhibiting their growth, adhesion, migration, and invasion properties. This implies the high possibility that the urologists may apply the results to use it intravesically before, during and after the transurethral resection of bladder tumour in addition to its conventional usage by oral and parenteral routes.

Antioxidant activity of Siamese neem tree (VP1209).

Leaves, fruits, flowers and stem bark extracts from the Siamese neem tree (Azadirachta indica A. Juss var. siamensis Valeton, Meliaceae) were assessed for antioxidant activity in vitro using the 1,1-diphenyl-2-picryl hydrazyl (DPPH) scavenging assay, total antioxidant activity and inhibition of lipid peroxidation in Chago K1 cancer cell culture by the thiobarbituric acid reactive substances (TBARS) method. The results showed that leaf aqueous extract, flower and stem bark ethanol extracts exhibited higher free radical scavenging effect on the DPPH assay with 50% scavenging activity at 26.5, 27.9 and 30.6 microg/ml, respectively. The total antioxidant activity of these extracts was found to be 0.959, 0.988 and 1.064 mM of standard trolox, respectively. At 100 microg/ml, the flower ethanol and leaf aqueous extracts significantly decreased malondialdehyde (MDA) levels (46.0 and 50.6%, respectively) by the TBARS method. The results suggest that extracts from leaf, flower and stem bark of the Siamese neem tree have strong antioxidant potential. This report supports the ethnomedical use of young leaves and flowers of this plant as a vegetable bitter tonic to promote good health.

Antioxidant Effect of Berberine and its Phenolic Derivatives Against Human Fibrosarcoma Cells.

Berberine (B1), isolated from stems of Coscinium fenestratum (Goetgh.) Colebr, was used as a principle structure to synthesize three phenolic derivatives: berberrubine (B2) with a single phenolic group, berberrubine chloride (B3) as a chloride counter ion derivative, and 2,3,9,10-tetra-hydroxyberberine chloride (B4) with four phenolic groups, to investigate their direct and indirect antioxidant activities. For DPPH assay, compounds B4, B3, and B2 showed good direct antioxidant activity (IC50 values=10.7±1.76, 55.2±2.24, and 87.4±6.65 µM, respectively) whereas the IC50 value of berberine was higher than 500 µM. Moreover, compound B4 exhibited a better DPPH scavenging activity than BHT as a standard antioxidant (IC50=72.7±7.22 µM) due to the ortho position of hydroxyl groups and its capacity to undergo intramolecular hydrogen bonding. For cytotoxicity assay against human fibrosarcoma cells (HT1080) using MTT reagent, the sequence of IC50 value at 7-day treatment stated that B1

Suppression of human fibrosarcoma cell metastasis by Phyllanthus emblica extract in vitro.

Phyllanthus emblica (PE) is known to exhibit various pharmacological properties. This study aimed to evaluate the antimetastatic potential of a PE aqueous extract. Cytotoxicity to human fibrosarcoma cells, HT1080, was determined by viability assay using the 3-(4,5-dimethylthiazol,2-yl)-2,5-diphenyltetrazolium bromide (MTT) reagent. Cell migration and invasion were investigated using chemotaxis chambers containing membranes pre- coated with collagen IV and Matrigel, respectively. Cell attachment onto normal surfaces of cell culture plates was tested to determine the cell-adhesion capability. The molecular mechanism of antimetastatic activity was assessed by measuring the gene expression of matrix metalloproteinases, MMP2, and MMP9, using reverse transcription-polymerase chain reaction (RT-PCR) assay. The mRNA levels of both genes were significantly down-regulated after pretreatment with PE extract for 5 days. Our findings show the antimetastatic function of PE extract in reducing cell proliferation, migration, invasion, and adhesion in both dose- and time-dependent manners, especially growth arrest with low IC50 value. A decrease in the expression of both MMP2 and MMP9 seems to be the cellular mechanism for antimetastasis in this case. There is a high potential to use PE extracts clinically as an optional adjuvant therapeutic drug for therapeutic intervention strategies in cancer therapy or chemoprevention.

Antioxidant effects of gamma-oryzanol on human prostate cancer cells.

BACKGROUND: To assess the antioxidant effects of gamma-oryzanol on human prostate cancer cells. MATERIALS AND METHODS: Cytotoxic activity of gamma-oryzanol on human DU145 and PC3 prostate cancer cells was determined by proliferation assay using 3-(4, 5-dimethylthiazol, 2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) reagent. mRNA levels of genes involved in the intracellular antioxidant system, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione reductase (GSR) were determined by reverse transcription-polymerase chain reaction (RT-PCR). Cancer cell lysates were used to measure lipid peroxidation using thiobarbituric acid reactive substance (TBARS). Glutathione contents of the cell lysates were estimated by the reaction between sulfhydryl group of 5, 5'-dithio (bis) nitrobenzoic acid (DTNB) to produce a yellow- color of 5-thio-2-nitrobenzoic acid using colorimetric assay. Catalase activity was also analysed by examining peroxidative function. Protein concentration was estimated by Bradford's assay. RESULTS: All concentrations of gamma-oryzanol, 0.1-2.0mg/ml, significantly inhibited cell growth in a dose- and time-dependent fashion in both prostate cancer cell lines, DU145 and PC3. Gene expression of catalase in DU145 and PC3 exposed to gamma-orizanol at 0.5mg/ml for 14 days was down regulated, while mRNA of GPX was also down regulated in PC3. The MDA and glutathione levels including catalase activity in the cell lysates of DU145 and PC3 treated with gamma-oryzanol 0.1 and 0.5mg/ml were generally decreased. CONCLUSIONS: This study highlighted effects of gamma-oryzanol via the down-regulation of antioxidant genes, catalase and GPX, not cytotoxic roles. This might be interesting for adjuvant chemotherapy to make prostate cancer cells more sensitive to free radicals. It might be useful for the reduction of cytotoxic agents and cancer chemoprevention.

Comparison of bioactive compounds content, free radical scavenging and anti-acne inducing bacteria activities of extracts from the mangosteen fruit rind at two stages of maturity.

Contents of bioactive components, free radical scavenging and anti-acne producing bacteria activities of young and mature fruit rind extracts of mangosteen were compared. The young fruit rind extract contained significantly higher contents of phenolics and tannins and promoted higher free radical scavenging activity than the mature fruit rind extract, while the later extract contained higher contents of flavonoids and alpha-mangostin xanthone and gave higher anti-acne producing bacteria activity than the young fruit rind extract. Thus, the young and mature stages of mangosteen fruit rind should be beneficial for further development of antioxidant and anti-acne pharmaceutical preparations, respectively.

Comparison of free radical scavenging activity of Siamese neem tree (Azadirachta indica A. Juss var. siamensis Valeton) leaf extracts prepared by different methods of extraction.

OBJECTIVE: The aim of this study was to investigate the antioxidant activity of the aqueous extracts of leaves of Siamese neem tree (Azadirachta indica A. Juss var. siamensis Valeton) from several extracting and drying methods using 2,2-diphenyl-1-picrylhydrazyl (DPPH)-scavenging assay. MATERIALS AND METHODS: The leaves of Siamese neem tree were extracted using percolation, decoction, maceration, soxhlet extraction, freeze drying or spray drying methods. The extract was tested for antioxidant activity using DPPH-scavenging assay. Thin-layer chromatography of the extract from decoction was also investigated. RESULTS: The freeze drying method gave the highest yield (51.50%, w/w) of crude extract, while decoction gave the most effective DPPH-scavenging activity (EC(50): 31.4 microg/ml). Thin-layer chromatography analysis was used to screen the leaf extract obtained using decoction, and the chromatogram showed spots corresponding to quercetin and rutin flavonoids which exhibited antioxidant activities (EC(50): 2.29 and 34.67 microg/ml, respectively). CONCLUSION: Siamese neem tree leaf extracts possessed free radical scavenging activity against the DPPH radical. The most active extract was obtained with the leaf decoction method. It showed antioxidant activity with EC(50) of 31.4 microg/ml.

Phytochemical and antioxidant studies of Laurera benguelensis growing in Thailand

The aim of this study was to investigate metabolites of the lichen Laurera benguelensis. A high-performance liquid chromatographic (HPLC) method has been developed for the characterization of xanthones and anthraquinones in extracts of this lichen. Lichexanthone, secalonic acid D, norlichexanthon, parietin, emodin, teloschistin and citreorosein were detected in the lichen samples, which were collected from two places in Thailand. Components of the lichen were identifed by relative retention time and spectral data. This is the frst time that a detailed phytochemical analysis of the lichen L. benguelensis was reported and this paper has chemotaxonomic signifcance because very little has been published on the secondary metabolites present in Laurera species. Some of the metabolites were detected for the frst time in the family Trypetheliaceae. The results of preliminary testing of benzene extract and its chloroform and methanol fractions showed that all samples showed a weak radical scavenging activity. The chloroform extract showed the highest antioxidant activity.