Preparation of Curcuma comosa tablets using liquisolid techniques: In vitro and in vivo evaluation.

Curcuma comosa (C. comosa) is a Thai medicinal herb that provides numerous pharmacologic activities due to its estrogen-like action. This study aimed to investigate the use of liquisolid technique to prepare tablets containing oleoresin-like crude extract of C. comosa, and to improve the dissolution profiles of its major compounds, diarylheptanoids (DAs). Free flowing powders of C. comosa extract were obtained by adsorption onto solid carriers, microcrystalline cellulose, with colloidal silica as coating material. FTIR results ruled out possible interactions between C. comosa extract and excipients. The results indicated that all of liquisolid tablets met the USP requirements. The release of DAs were significantly increased through liquisolid formulations, compared to crude extract. By decreasing the ratio of carrier to coating from 20 to 10, an improvement in dissolution rate was observed. Addition of additives - namely polymer (polyvinyl pyrrolidone) and/or nonvolatile liquid (propylene glycol) affected tablet properties which involved longer disintegration time and lower DA dissolution. Optimized C. comosa liquisolid formulation was prepared in a carrier to coating ratio of 10 without additives. Stability studies showed that physical properties of liquisolid tablet were not affected by aging, but percent remaining and dissolution profiles of DAs were influenced by storage temperature. In vivo pharmacokinetic behavior of the optimized C. comosa liquisolid tablets was investigated following a single oral administration to rabbits. The results proved that the method used for preparation of liquisolid led to C. comosa tablets with low variation in content uniformity and tablet properties, as well as enhanced dissolution behavior.

Antioxidant activity of ginger extract as a daily supplement in cancer patients receiving adjuvant chemotherapy: a pilot study.

PURPOSE: The aim of this study was to examine the antioxidant activity of ginger extract oral supplement in newly diagnosed cancer patients receiving adjuvant chemotherapy compared to placebo. PATIENTS AND METHODS: Newly diagnosed cancer patients receiving moderate-to-high emetogenic potential adjuvant chemotherapy were randomized to receive either a ginger extract (standardized 6-gingerol 20 mg/day) or a placebo 3 days prior to chemotherapy, which they continued daily. Oxidant/antioxidant parameters, including the activities of superoxide dismutase (SOD) and catalase (CAT) and levels of glutathione peroxidase (GPx), total glutathione (GSH/GSSG), lipid peroxidation products detected as malondialdehyde (MDA) and NO2-/NO3-, were measured at baseline and at days 1, 22, 43 and 64 after undergoing chemotherapy. Two-sided statistical analysis, with P < 0.05, was used to determine statistical significance. RESULTS: A total of 43 patients were included in the study: 19 and 24 patients were randomly assigned to the ginger group and placebo group, respectively. Antioxidant activity parameters, including SOD, CAT, GPx and GSH/GSSG, were significantly increased at day 64 in the ginger group compared to those in the placebo group, while MDA and NO2-/NO3- levels were significantly decreased (P < 0.0001). When compared to the baseline, the activities of SOD and CAT and the levels of GPx and GSH/GSSG were significantly higher on day 64 (P = 0.01), while the blood levels of MDA and NO2-/NO3- were significantly decreased (P < 0.01). CONCLUSION: Daily supplement of ginger extract started 3 days prior to chemotherapy has been shown to significantly elevate antioxidant activity and reduce oxidative marker levels in patients who received moderate-to-high emetogenic potential chemotherapy compared to placebo.

Antioxidant effect of Phyllanthus amarus after moderate-intensity exercise in sedentary males: a randomized crossover (double-blind) study.

[Purpose] We aimed to evaluate the effects of Phyllanthus amarus (PA) on oxidative stress and damage, inflammation, and soreness in muscle after a single session of moderate-intensity exercise. [Subjects and Methods] Twelve men randomly participated in 2, three-day phases with a one-week washout period. On the first day, participants consumed two capsules of PA or placebo control (CTL) before 20 min of cycling. They then consumed four capsules on the same day after exercise and six capsules/day for the next two days. Blood samples were obtained before, immediately after exercise and 24 h and 48 h after exercise. The pain tolerance was measured at both legs. [Results] Plasma vitamin C levels in the PA group were higher than those in the CTL group after exercise. At 48 h after exercise, vitamin C levels were higher in the PA group, but those in the CTL group were lower than the pre-exercise levels. However, plasma levels of creatine kinase were increased in both groups after exercise compared with the pre-exercise levels. The neutrophil count was higher immediately after exercise than the pre-exercise levels in the CTL group. [Conclusion] Acute supplementation with PA improves antioxidant status after a single session of moderate-intensity exercise.

Antioxidant and anti-nociceptive effects of Phyllanthus amarus on improving exercise recovery in sedentary men: a randomized crossover (double-blind) design.

BACKGROUND: Phyllanthus amarus (PA) is a herbal plant containing antioxidant compounds that scavenge free radicals. The reduced oxidative stress may decrease muscle damage leading to early recovery from muscle soreness. This study aimed to evaluate the effects of PA powder on oxidative stress, muscle damage, leukocyte counts, inflammation, and muscle soreness after a single bout of high-intensity exercise. METHODS: Twelve men participated in two 3-day phases separated by a 1-week washout in a randomized double-blinded, crossover design. On day 1, randomly divided participants ingested two capsules of either PA (PA group) or placebo (PLA group) 20 min before a single bout of cycling at high intensity for 20 min followed by four capsules (two capsules after lunch and dinner), and six capsules/day for the next 2 days. Blood samples were collected before, immediately after, and 24 and 48 h after the exercise. Pain threshold was measured at the mid-thigh on both legs. RESULTS: Malondialdehyde concentration in the PA group was lower than that in the PLA group (p < 0.05) 48 h after high-intensity exercise. Vitamin C concentration was greater in the PA than in the PLA group (p < 0.05) immediately after high-intensity exercise. Pain threshold in both legs in the PA group was higher than in the PLA group 24 and 48 h after high-intensity exercise. There were no significant differences in creatine kinase, leukocyte counts or inflammation between groups. CONCLUSION: Acute PA supplementation reduced oxidative stress and muscle soreness induced by high-intensity exercise.

Flow cytometry analysis of cancer cell death induced by the extract of Thai plant Ellipeiopsis cherrevensis.

  The mechanism of cancer cell death induced by KP018, an ethanol extract of the Thai plant Ellipeiopsis cherrevensis, was examined in paclitaxel-resistant HepG2 (PR-HepG2) and colon-26 cells using flow cytometry. In PR-HepG2 cells, KP018 induced necrosis in a concentration-dependent manner. Necrosis of PR-HepG2 cells induced by KP018 as well as by hydrogen peroxide was suppressed by co-treatment of the cells with N-acetylcysteine. KP018 decreased the viability of colon-26 cells with an IC50 value of 15.1 µg/mL, which was estimated by XTT assay. As observed in PR-HepG2 cells, KP018 induced necrosis and the necrosis was suppressed by N-acetylcysteine in colon-26 cells. In addition, using colon-26 solid tumor-bearing mice, KP018 was found to suppress tumor growth without apparent toxicities under in vivo conditions. These results indicate that KP018 induces necrosis rather than apoptosis in these cancer cells, and reactive oxygen species such as hydrogen peroxide would be involved in KP018-induced necrosis. KP018 may be a useful source to search for a new anticancer drug that can be used for the chemotherapy of multidrug-resistant tumors.

Effect of Thai plant extracts on P-glycoprotein function and viability in paclitaxel-resistant HepG2 cells.

The effects of ethanol extracts from Thai plants on P-glycoprotein (P-gp) function and cell viability were examined using paclitaxel-resistant HepG2 (PR-HepG2) cells. KP018 from Ellipeiopsis cherrevensis and AT80 from Ancistrocladus tectorius increased both rhodamine 123, a typical P-gp substrate, and [(3)H]paclitaxel uptake in PR-HepG2 cells. However, some extracts such as MT80 from Microcos tomentosa increased rhodamine 123, but not [(3)H]paclitaxel, uptake, while MM80 from Micromelum minutum increased only [(3)H]paclitaxel uptake. Thus, the effects of extracts of Thai plants on rhodamine 123 uptake were not necessarily the same as those on [(3)H]paclitaxel uptake. Purified compounds such as bergapten did not affect the uptake of either substrate. KP018, AT80, and MM80 increased [(3)H]paclitaxel uptake and decreased the cell viability in a concentration-dependent manner. Among these extracts, KP018 showed the most potent cytotoxicity. The cytotoxic potency of KP018 on PR-HepG2 cells was similar to that on wild-type HepG2 cells, and was not potentiated by verapamil. At concentrations resulting in no cytotoxicity, AT80 and MM80 potentiated paclitaxel-induced cytotoxicity in PR-HepG2 cells. These results indicate that K018 may be a useful source to search for a new anticancer drug, while AT80 and MM80 may be useful as modulators of P-gp-mediated multidrug resistance in cancer cells.

Pharmacological activity of Kaempferia parviflora extract against human bile duct cancer cell lines.

A crude ethanol extract of Kaemperia parviflora Wall. Ex Baker and a purified compound, 5,7,4-trimethoxyflavone (KP.8.10), were evaluated for pharmacological effects on human cholangiocarcinoma cell lines (HuCCA-1 and RMCCA-1). The cells were incubated with various concentrations of extract for various time periods and metabolic activity (MTT assay) was assessed for cell viability. The results showed a dose-dependent effect of both crude ethanol extract and the pure compound. CC50s for the crude extract on HuCCA-1 and RMCCA-1 cells were 46.1 microg/ml and 62.0 microg/ml, respectively. Values for the pure compound could not be determined because of solubility problems. Interestingly, K. parviflora ethanol extract and KP.8.10 at low concentrations (10-20 microg/ml and 2.5-5 microg/ml, respectively) markedly reduced rhHGF-induced invasion by HuCCA-1 and RMCCA-1 cells across matrix-coated transwell plates. Higher concentrations of K. parviflora ethanol extract (60 and 80 microg/ml) and KP.8.10 (20 microg /ml) dramatically changed the cellular morphology and caused death in both cell types. KP.8.10 further exhibited progressive action via caspase-3 mitochondrial enzyme activation, enhancing cellular toxicity in a time-dose dependent fashion. Therefore, 5,7,4-trimethoxyflavone appeared to be a bioactive component of K. parviflora extract capable of exerting anti-cancer action. The results suggested a benefit of this edible plant in prevention and treatment of cholangiocarcinoma.

Evaluation of chikusetsusaponin IVa isolated from Alternanthera philoxeroides for its potency against viral replication.

Chikusetsusaponin IVa and calenduloside E were isolated from the whole plant of Alternanthera philoxeroides (Mart.) Griseb (Amaranthaceae) and evaluated for their antiviral activities. Chikusetsusaponin IVa showed antiviral activities against HSV-1, HSV-2, human cytomegalovirus, measles virus, and mumps virus with selectivity indices (CC (50)/IC (50)) of 29, 30, 73, 25, and 25, respectively. On the other hand, calenduloside E showed no antiviral effects against any of the viruses tested. The mode of HSV-2 action of chikusetsusaponin IVa was determined under different experimental conditions. The anti-HSV-2 target of the compound might be mainly related to direct inactivation of virus particles and to the inhibition of release of progeny viruses from infected cells, but it is not related to inhibition of viral attachment, cell penetration, and viral protein synthesis. This compound also provided in vivo efficacy in a mouse model of genital herpes caused by HSV-2. These results demonstrate that chikusetsusaponin IVa might be a candidate of antiherpetic agents.

Effectiveness of green tea on weight reduction in obese Thais: A randomized, controlled trial.

This study was undertaken to investigate the effects of green tea on weight reduction in obese Thais. A randomized, controlled trial involving 60 obese subjects (body mass index, BMI > 25 kg/m2) was conducted. All subjects consumed a Thai diet containing 3 meals (8373.6 kJ/day) for 12 weeks, prepared by the Nutritional Unit at Srinagarind Hospital. The diet contained 65% carbohydrates, 15% protein, and 20% fat. Body weight, BMI, body composition, resting energy expenditure, and substrate oxidation were measured at baseline, and during weeks 4, 8, and 12 of the study. Serum levels of leptin and urine VMA were measured at baseline and during the 12th week. Differences over time and between the treatments (green tea or placebo) over time were determined using two-factor ANOVA with repeated measures. In comparing the two groups, differences in weight loss were 2.70, 5.10, and 3.3 kg during the 4th, 8th, and 12th weeks of the study, respectively. At the 8th and 12th weeks of the study, body weight loss was significantly different (P < 0.05). At the 8th week, the difference in resting energy expenditure was 183.38 kJ/day (P < 0.001), the difference in the respiratory quotient was 0.02 (P < 0.05), and no significant differences existed in satiety score, food intake, or physical activity. Urine VMA was significantly different in the 12th week of the study (P < 0.05). We conclude that green tea can reduce body weight in obese Thai subjects by increasing energy expenditure and fat oxidation.

Modulation of function of multidrug resistance associated-proteins by Kaempferia parviflora extracts and their components.

In this study, the effects of extracts and flavone derivatives from the rhizome of Kaempferia parviflora on multidrug resistance associated-proteins (MRP)-mediated transport in A549 cells were examined. The cells employed express MRP1 and MRP2, but not P-glycoprotein. The cellular accumulation of calcein, an MRP substrate, was significantly increased by various MRP inhibitors without being affected by verapamil, a typical P-glycoprotein inhibitor. Ethanol and aqueous extracts from K. parviflora rhizome increased the accumulation of calcein and doxorubicin in A549 cells in a concentration-dependent manner. The inhibitory potency of the ethanol extract for MRP function was greater than that of the aqueous extract. Among six flavone derivatives isolated from K. parviflora rhizome, 5,7-dimethoxyflavone exhibited a maximal stimulatory effect on the accumulation of doxorubicin in A549 cells. The accumulation of doxorubicin was increased by four flavone derivatives without 5-hydroxy group, but not by the other two flavone derivatives with 5-hydroxy group. In addition, 5,7-dimethoxyflavone and 3,5,7,3',4'-pentamethoxyflavone decreased resistance to doxorubicin in A549 cells. These findings indicate that extracts and flavone derivatives from the rhizome of K. parviflora suppress MRP function, and therefore may be useful as modulators of multidrug resistance in cancer cells.

Effects of Kaempferia parviflora extracts and their flavone constituents on P-glycoprotein function.

The purpose of this study was to examine the effects of extracts and flavone derivatives from the rhizome of Kaempferia parviflora on P-glycoprotein (P-gp)-mediated transport in LLC-GA5-COL150, a transfectant cell line of a porcine kidney epithelial cell line LLC-PK1 with human MDR1 cDNA. Ethanol extract obtained from Kaempferia parviflora rhizome significantly increased the accumulation of rhodamine 123 and daunorubicin, P-gp substrates, in LLC-GA5-COL150 cells, but not in LLC-PK1 cells. The aqueous extract also increased the accumulation in LLC-GA5-COL150 cells with lower potency than the ethanol extract. The effects of flavone derivatives isolated from the rhizome of Kaempferia parviflora on P-gp function were examined. Among six flavones tested, 3,5,7,3',4'-pentamethoxyflavone most potently increased the accumulation of rhodamine 123 and daunorubicin in LLC-GA5-COL150 cells in a concentration-dependent manner. In addition, 5,7-dimethoxyflavone to lesser degree increased rhodamine 123 accumulation in LLC-GA5-COL150 cells. In contrast, the other four flavone derivatives had no significant effect on the accumulation of rhodamine 123 in LLC-GA5-COL150 cells in a concentration range tested. These results indicate that extracts and flavone derivatives from the rhizome of Kaempferia parviflora can inhibit P-gp function, which may be useful for overcoming P-gp-mediated multidrug resistance and improving the oral bioavailability of anticancer agents.

Membrane transport of andrographolide in artificial membrane and rat small intestine.

In the present study, the possible drug interactions of andrographolide with co-administering drugs such as acetaminophen, amoxycillin, aspirin, chlorpheniramine and norfloxacin to treat various infectious and inflammatory diseases that may be induced during absorption process were examined using artificial lipophilic membrane and everted rat intestine. The membrane transport of andrographolide across the artificial membrane was not affected by different pH of the medium (simulated gastric and intestinal fluids), different concentrations of andrographolide and co-administered drugs examined. In everted rat intestine, above co-administered drugs examined showed no significant effect on andrographolide membrane transport. The participation of efflux transporters such as P-glycoprotein and MRP2 in andrographolide transport was then examined, since andrographolide is a diterpene compound and some diterpene compounds are known as P-glycoprotein substrates. Cyclosporine, a P-glycoprotein/MRP2 inhibitor, significantly suppressed the efflux transport of andrographolide in distal region of intestine, whereas probenecid, an MRP inhibitor, showed no significant effect in both proximal and distal regions of intestine. These results suggest that P-glycoprotein, but not MRP, is participated in the intestinal absorption of andrographolide and P-glycoprotein-mediated drug interactions occur depending on the co-administered drugs and its concentrations.

Impact of Andrographis paniculata crude extract on mouse hepatic cytochrome P450 enzymes.

Modulatory influence of Andrographis paniculata crude extract on cytochrome P450 (CYP) enzymes was performed by administration of the crude extract of Andrographis paniculata to ICR male mice. Total hepatic P450 content was not significantly modified by either the aqueous or the alcoholic extracts of Andrographis paniculata. Assessment of hepatic microsomal P450 activities by alkoxyresorufin O-dealkylations noted that both the aqueous and alcoholic extracts of Andrographis paniculata significantly increased ethoxyresorufin O-dealkylase and pentoxyresorufin O-dealkylase activities, while those of methoxyresorufin O-dealkylase activities were not elevated. These results suggested that Andrographis paniculata might effectuate hepatic cytochrome P450 enzymes of which CYP1A1 and CYP2B are the responsive P450 isoforms.