Pharmacokinetics of cucurbitacin B from Trichosanthes cucumerina L. in rats.

BACKGROUND: Cucurbitacin B is the major bioactive constituent in Trichosanthes cucumerina L. fruits, which the pharmacological properties have been studied for decades particularly an anti-tumor activity. The pharmacokinetic profile of this compound is still limited and investigation is needed for further phytopharmaceutical product development. This study aimed to investigate the pharmacokinetic profile of cucurbitacin B after administering the compound at different doses and routes to rats. METHODS: Male Wistar rats (n = 6) were treated by cucurbitacin B extracted from Trichosanthes cucumerina L. The cucurbitacin B was administered at 0.1 mg/kg intravenously or by oral gavage at 2-4 mg/kg. Blood samples and internal organs were collected serially within 24 h after administration. Urine and feces were collected from time 0 to 48 h. The level of cucurbitacin B in biological samples was determined by liquid chromatography-tandem mass spectrometry. RESULTS: The absolute oral bioavailability of cucurbitacin B was approximately 10%. The maximum concentration in plasma after normalization by dose ranged from 4.85-7.81 µg/L and the time to reach maximum value was approximately within 30 min after oral dosing. The level of cucurbitacin B in plasma increased proportionally to the given dose. After intravenous administration, cucurbitacin B had a large volume of distribution of about 51.65 L/kg and exhibited a high tissue to plasma concentration ratio, approximately 60 to 280-fold in several organs. Negligible amount of unchanged cucurbitacin B could be detected in urine and feces and accounted less than 1% of administered dose. CONCLUSION: Cucurbitacin B had low oral bioavailability, but could be distributed extensively into internal organs with a high volume of distribution and tissue to plasma ratio. Only negligible amounts of unchanged cucurbitacin B were excreted via urine and feces suggesting that the compound might be biotransformed before undergoing an excretion. Further studies of the metabolic pathway and tissue uptake mechanism are required to strategize the future development of cucurbitacin B into clinical studies.

Inhibitory effect of Phlai capsules on skin test responses among allergic rhinitis patients: a randomized, three-way crossover study.

BACKGROUND: Zingiber cassumunar Roxb., commonly known as Phlai in Thai, has been used as a traditional medicine in Thailand for the treatment of various diseases, including inflammation and chronic airway disease. OBJECTIVE: The purpose of this study was to assess the antihistaminic effect of Phlai on skin testing. DESIGN, SETTING, PARTICIPANTS AND INTERVENTION: This was a randomized, open-label, three-way crossover study. Twenty allergic rhinitis (AR) patients were enrolled. In randomized sequence, patients received a single dose of Phlai capsules (100 or 200 mg) or loratadine (10 mg) with a washout period of 1 week between each treatment. MAIN OUTCOME MEASURES: Skin prick testing for histamine and common aeroallergen (house dust mite) were performed before treatment and after 1, 2, 3, 4, 6, 8, 12 and 24 hours of treatment. The main treatment outcomes were the mean wheal and flare responses to the skin prick test after treatment. RESULTS: Both 100 mg and 200 mg Phlai doses suppressed wheal and flare responses to house dust mite allergen, but only 200 mg of Phlai capsules significantly suppressed wheal and flare responses to histamine. Repeated measures analysis of variance showed that loratadine caused more wheal and flare suppression than Phlai capsules in responses to the histamine skin prick test. However, there were no significant differences among the effects of 100 mg Phlai capsules, 200 mg Phlai capsules and loratadine in suppression of wheal and flare induced by the mite skin prick test. Both doses of Phlai were well-tolerated with no adverse events. CONCLUSION: Both 100 mg (compound D 4 mg) and 200 mg (compound D 8 mg) Phlai capsules, when taken as a single therapeutic dose, inhibited skin reactivity to histamine and mite skin prick tests in AR patients. TRIAL REGISTRATION: Thai clinical trial registry (TCTR20160510001).

Pharmacokinetics of Compound D, the Major Bioactive Component of Zingiber cassumunar, in Rats.

Rhizomes of Zingiber cassumunar have been used for many years in traditional Thai medicine as an anti-inflammatory agent. The major bioactive component of this plant is Compound D [E-4-(3', 4'-dimethoxyphenyl)but-3-en-1-ol], which is a strong smooth muscle relaxant, and has antihistamine and anti-inflammatory actions. There is, however, incomplete information available for the pharmacokinetics of Compound D in mammals. In this study, we examined the pharmacokinetic profiles of Compound D in male Wistar rats. A standardized extract of Z. cassumunar containing 4 % w/w Compound D was administered intravenously at 25 mg/kg or by oral gavage at 25, 75, or 250 mg/kg to Wistar rats. Blood, tissues, urine, and feces were collected from 0 to 48 h after dosing and the level of Compound D was determined by liquid chromatography-tandem mass spectrometry. The concentration of Compound D ranged from 10-100 µg/L, reached a maximum approximately 0.15 h after oral dosing. Compound D exhibited an excellent tissue to plasma ratio, ranging from 1- to 1000 in several organs at 1-4 h after oral dosing. Less than 1 % of unchanged Compound D was excreted in the urine and feces. Further studies on tissue uptake and metabolite identification are required to obtain complete pharmacokinetic information and to develop appropriate dosing strategies of Compound D and the standardized extract of Z. cassumunar.

Antibacterial and Antiproliferative Activities of Plumericin, an Iridoid Isolated from Momordica charantia Vine.

Plumericin, an iridoid lactone, was isolated with relatively high yield from Momordica charantia vine using the supercritical fluid extraction (SFE) and the separation box (Sepbox) comprising dual combination of high-performance liquid chromatography and solid phase extraction. This compound showed antibacterial activity against Enterococcus faecalis and Bacillus subtilis with minimum inhibitory concentration (MIC) values better than cloxacillin. Plumericin potently inhibited proliferation of two leukemic cancer cell lines: they were acute and chronic leukemic cancer cell lines, NB4 and K562, with the effective doses (ED50) of 4.35 ± 0.21 and 5.58 ± 0.35 µg/mL, respectively. In addition, the mechanism of growth inhibition in both cell lines was induced by apoptosis, together with G2/M arrest in K562 cells.

Overview of Botanical Status in EU, USA, and Thailand.

The botanical status in EU, USA, and Thailand is different owing to the regulatory status, the progress of science, and the influence of culture and society. In the EU, botanicals are positioned as herbal medicinal products and food supplements, in the US they are regulated as dietary supplements but often used as traditional medicines, and in Thailand, they are regulated and used as traditional medicines. Information for some of the most popular botanicals from each country is included in this review.

Antiherpetic Effects of Gynura procumbens.

The ethanol extract of Gynura procumbens showed virucidal and antireplicative actions against herpes simplex virus HSV-1 and HSV-2. It was further chromatographed on MCI gel CHP20P column giving the extract fractions F1 (water), F2 (water-methanol) F3 (methanol), and F4 (ethyl acetate). All but F1 had virucidal action against both viral types. We reported here the active compounds from F2 and F3. The antiherpetic compounds of F2 was a mixture of dicaffeoylquinic acids with virucidal and antireplicative actions against HSV-2 (IC50 96.0 and 61.0 µ g/mL, resp.) Virucidal compounds of F3 were a mixture of ß -sitosterol and stigmasterol (IC50 250.0 µ g/mL against HSV-1), a mixture of ß -sitosteryl and stigmasteryl glucosides (IC50 50.0 µ g/mL against HSV-2) and 1, 2-bis-dodecanoyl-3- α -D-glucopyranosyl-sn-glycerol (IC50 of 40.0 µ g/mL against HSV-2). Herbal products containing 1 and 2% of standardized ethanol extract were prepared. Double-blind randomized controlled clinical trial of the products was performed in patients with recurrent herpes labialis. Results showed that the number of patients, whose lesions healed within 7 days and the average healing time of both groups differed insignificantly. Viral culture on D7 indicated a decrease of infected patients from 48.7% to 7.69% in treated group whereas in placebo group the infected patients decreased from 31.25% to 20.00%. The viral reduction in treated group indicated the benefit of the product. Insignificant result might arise from a low number of participated patients and insufficient concentration of plant extract in herbal product.

Antiproliferative Effect and the Isolated Compounds of Pouzolzia indica.

Previous report showed the high potent antiproliferative effect of the methanolic part extracted from the aerial parts of Pouzolzia indica on NB4 and HT93A acute leukemic cell lines with the IC50 values of 28.5 and 49.8 µ g/mL, respectively. The bioassay-guided fractionation of the methanolic part gave 5 fractions, that is, FFI-FFV. FFII, FFIII, and FFIV inhibited the above leukemic cell lines with the IC50 values of 15.1 (FFII), 14.4 (FFIII), 32.1 (FFIV), and 31.0 (FFII), 9.7 (FFIII), 10.5 (FFIV) µ g/mL, respectively. The compounds in these fractions were isolated using chromatographic technique. FFII contained friedelin 1, 28-hydroxy-3-friedelanone 2, and 7-methoxy-coumarin 3. FFIII contained 6, 7-dimethoxy-coumarin 4, scopoletin 5, methyl caffeate 6. FFIV contained sitosteryl glucoside 7 and a supposed glycosphingolipid 8. The chemical structures were elucidated by spectroscopic methods.

Inhibition of Wnt signaling by cucurbitacin B in breast cancer cells: reduction of Wnt-associated proteins and reduced translocation of galectin-3-mediated ß-catenin to the nucleus.

The cucurbitacins are tetracyclic triterpenes found in plants of the family Cucurbitaceae. Cucurbitacins have been shown to have anti-cancer and anti-inflamatory activities. We investigated the anti-cancer activity of cucurbitacin B extracted from Thai medicinal plant Trichosanthes cucumerina Linn. Cell viability was assessed by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Results indicated that cucurbitacin B from T. cucumerina Linn. has a cytotoxic effect on breast cancer cell lines SKBR-3 and MCF-7 with an IC50 of 4.60 and 88.75 µg/ml, respectively. Growth inhibition was attributed to G2/M phase arrest and apoptosis. Cyclin D1, c-Myc, and ß-catenin expression levels were reduced. Western blot analysis showed increased PARP cleavage and decreased Wnt-associated signaling molecules ß-catenin, galectin-3, cyclin D1 and c-Myc, and corresponding changes in phosphorylated GSK-3ß levels. Cucurbitacin B treatment inhibited translocation to the nucleus of ß-catenin and galectin-3. The depletion of ß-catenin and galectin-3 in the nucleus was confirmed by cellular protein fractionation. T-cell factor (TCF)/lymphoid enhancer factor (LEF)-dependent transcriptional activity was disrupted in cucurbitacin B treated cells as tested by a TCF reporter assay. The relative luciferase activity was reduced when we treated cells with cucurbitacin B compound for 24 h. Our data suggest that cucurbitacin B may in part induce apoptosis and exert growth inhibitory effect via interruption the Wnt signaling.

Antiproliferative effects of cucurbitacin B in breast cancer cells: down-regulation of the c-Myc/hTERT/telomerase pathway and obstruction of the cell cycle.

Naturally occurring cucurbitacins have been shown to have anticancer, antimicrobial and anti-inflammatory activities. In this study, we determined the effects of cucurbitacin B extracted from the Thai herb Trichosanthes cucumerina L. on telomerase regulation in three human breast cancer cell lines (T47D, SKBR-3, and MCF-7) and a mammary epithelium cell line (HBL-100). Cell viability after treatment with cucurbitacin B, which is an active ingredient of this herb, was assessed. Telomeric Repeat Amplification Protocol (TRAP) assays and RT-PCR (qualitative and realtime) were performed to investigate activity of telomerase as well as expression of human telomerase reverse transcriptase (hTERT) and c-Myc. The c-Myc protein level was also determined in SKBR-3 and HBL-100 cells. Our results show that the cucurbitacin B inhibits growth and telomerase activity in the three breast cancer cell lines and exerts an obvious inhibitory effect in the estrogen receptor (ER)-negative breast cancer SKBR-3 cells. The expression of hTERT and c-Myc were also inhibited by cucurbitacin B, In addition, a clear reduction of c-Myc protein was observed after treatment in SKBR-3 cells even with a concentration of cucurbitacin B that was ten-times lower compared to the concentration used for HBL-100. Our findings imply that cucurbitacin B exerts an anticancer effect by inhibiting telomerase via down regulating both the hTERT and c-Myc expression in breast cancer cells.

Cytotoxic properties of root extract and fruit juice of Trichosanthes cucumerina.

The root extract of Trichosanthes cucumerina L. and bryonolic acid (1), its main constituent, as well as the fruit juice and cucurbitacin B (3), its main constituent, were tested for cytotoxicity against four human breast cancer cell lines (SKBR3, MCF7, T47D, and MDA-MB435), two lung cancer cell lines (A549 and SK-LU1), and one colon cancer cell line (Caco-2). The root extract had higher IC (50) values than bryonolic acid (1) against three breast cancer cell lines (MCF7 = 267/121, T47D = 316/124, MDA-MB435 = 140/90 microL/mL) and one lung cancer cell line (A549 = 106/100 microL/mL). The fruit juice also had higher IC (50) values than cucurbitacin B (3) against the four breast cancer cell lines (131/73, 375/35, 249/60, and 156/26 microL/mL, respectively) and one lung cancer cell line (141/41 microL/mL) as shown above, as well as against the colon cancer cell line (101/1.5 microL/mL). However, the root extract inhibited SK-LU1 more strongly than did the fruit juice, cucurbitacin B (3), and bryonolic acid (1) (149/169/180/>500 microL/mL, respectively). The root extract inhibited the two lung and three breast cancer cell lines (SKBR3, MDA-MB435, and MCF7) more strongly than the fruit juice. Bryonolic acid (1) inhibited MDA-MB435 somewhat better than the other tested human cancer cell lines. The fruit juice inhibited the colon cancer cell line (Caco-2) more strongly than the root extract. Cucurbitacin (3) inhibited human cancer cell lines, especially Caco-2, much more strongly than bryonolic acid (1). In addition to bryonolic acid (1), bryononic acid (2), cucurbitacin B (3), and dihydrocucurbitacin B (4) also were isolated from the root extract.

Antiproliferative effect of Erycibe elliptilimba on human breast cancer cell lines.

Erycibe elliptilimba Merr. & Chun., family Convolvulaceae, is a Thai traditional medicine which has long been prescribed for various infectious and malignant diseases. Bio-assays of extracts from Erycibe elliptilimba Merr. & Chun. showed that a fraction (fraction 3) from an methanolic extract had an antiproliferative effect on SKBR3 and MDA-MB435 human breast cancer cells. The ED50 value of Erycibe elliptilimba Merr. & Chun. fraction 3 was 56.07 and 30.61 microg/ml for SKBR3 and MDA-MB435, respectively. After 48 h of exposure, this fraction at a concentration of 100 microg/ml significantly reduced cell proliferation in both cancer cells. In MDA-MB435 cells, cell cycle analysis showed that the herb extract fraction 3 induced the accumulation of cells in G2/M phase, whereas no significant change in cell cycle was detected in SKBR3 cells. The results indicated that the extract fraction 3 could induce cell cycle arrest in some way. However, further investigation is needed to assess the molecular mechanisms mediated anticancer activities of this plant.

Antibacterial activities of four Thai medicinal plants.

Medicinal plants have long been used and prescribed in Thailand for centuries. Some of them have been used for treating various diseases including infectious diseases. Pouzolzia pentandra Benn., Gelonium multiflorum A. Juss., Erycibe elliptilimba Merr. and Chun., Balanophora abbreviate Bl. are Thai medicinal plants from the Thai pharmacopoeia that have been prescribed for treating unknown fevers including some specific infectious diseases. This investigation demonstrated the effects of these Thai medicinal plants for their antibacterial activities by using the macrodilution assay. Based on the present study, the water methanol fraction (fraction 2) of Balanophora abbreviate Bl. showed the antibacterial activity at the MIC level of 250 microg/ml but the activity was bacteriostatic in its effects. Therefore, the use of these medicinal plants in controlling fever and infectious diseases appears to be justified and further investigations may be required to obtain more information.

Immunomodulatory effect and quantitation of a cytotoxic glycosphingolipid from Murdannia loriformis.

NMR signal reassignments for a cytotoxic glycosphingolipid compound, 2, ß-O-D-glucopyranosyl-2-(2'-hydroxy-Z-6'-enecosamide)sphingosine, isolated from an ethanolic extract of the herb Murdannia loriformis, have been achieved by use of FAB-MS, and 1D and 2D 1H and 13C NMR. The amount of 2 in the herb juice was quantitatively determined by use of a validated HPLC method (RP-18, MeOH-H2O, UV detection at 210 nm). The immunomodulatory effect of the herb juice and of 2 was proved by means of in vitro cellular immunological assays. Compound 2 at a concentration of 13 nmol L-1 stimulated PBMC proliferation and increased the CD 3,4:CD 3,8 ratio in T lymphocytes.