Limonoids and tricyclic diterpenoids from Azadirachta indica and their antitumor activities.

The chemical constituents of the roots, seeds, and bark of Azadirachta indica var. siamensis were investigated, leading to the isolation of six tricyclic diterpenoids and five limonoids, including two new compounds (2, 5). The structures were elucidated based on NMR spectroscopic techniques, mass spectrometry and single-crystal X-ray diffraction as well as comparison with the literature. Moreover, the cytotoxicity activities of the isolates were evaluated. The results indicated that the compounds 1-3, 5-9 exhibited cytotoxicities against one or more cancer cell lines tested, with IC50 values in the range of 1.7-88.1 µM. The mechanism of action studies indicated that the most active compound, compound 5, could induce the apoptosis of AZ521 cells. Furthermore, the Western blot analysis showed that compound 5 could reduce the expression levels of procaspases-3, -8, -9 and promote the expression of Bid and AIF.

Characterization, quantitation, similarity evaluation and combination with Na+,K+-ATPase of cardiac glycosides from Streblus asper.

Streblus asper Lour. (Moraceae) is a medicinal plant in Asian countries including India and Thailand, possessing activities of anti-tumor, anti-allergy, anti-parasitic and anti-bacterial. In this paper, characterization, quantitation and similarity evaluation of cardiac glycosides in different parts of S. asper were investigated by HPLC-Q-TOF-MS and chemometric methods. Then, the inhibition of Na+,K+-ATPase activity by the compounds isolated from S. asper was measured. Meanwhile, enzyme kinetics and molecular docking were determined to exhibit the combination modes between cardiac glycosides and Na+,K+-ATPase. As a result, twenty peaks of cardiac glycosides were assigned. Strophanthidin-3-O-α-l-rhamnopyranosyl-(1 → 4)-6-deoxy-ß-d-allopyranoside (1), glucostrebloside (2), strebloside (4) and mansonin (8) with a significant activity of inhibiting Na+,K+-ATPase (IC50 7.55-13.60 µM) were chosen for the determination of enzyme kinetics, exhibiting anticompetitive inhibitory characteristics towards Na+,K+-ATPase. Compound 4 could reasonably bind to the active sites of Na+,K+-ATPase, proved by molecular docking. Furthermore, the contents of the major compounds in four different parts of S. asper were extremely different, analyzed by chemometric methods, similarity analysis and principle compounds analysis. All these findings indicated that the contents of major compounds in different parts of S. asper were extremely different with a significant activity of inhibiting Na+,K+-ATPase, providing a reference for determination of effective part and administered dosage. The combination modes between cardiac glycosides and Na+,K+-ATPase were also revealed by enzyme kinetics and molecular docking, which provided a basis for further study of pharmacological activity.

Potent Anti-Proliferation on the Colon Cancer Cell Line (HT-29) of Liposomal Formulations Entrapped with Semi-Purified Job's Tears (Coix lacryma-jobi Linn.) Fractions.

Liposomes, entrapped with Job's Tears fractions, were prepared by the supercritical carbon dioxide fluid (scCO2) technique with and without sonication. Physical characteristics, which were the particle size, zeta potential, vesicular morphology, microviscosity and bioactivities including anti-proliferative, apoptotic and antioxidative activities of the S1L-S5L liposomal systems, were investigated. The potent anti-proliferative activity with the IC50 value of 4.44±2.31 ug/ml in a colon cancer cell (HT-29) was observed in the S5L. S5L also showed the apoptotic activity of 4.45±0.92% in an HT-29 cell. For antioxidative activities, the S3L showed the highest free radical scavenging activity and lipid peroxidation inhibition, whereas the S4L gave the highest metal chelating activity. This study has demonstrated the potent anti-proliferative activity on an HT-29 cell of the S5L liposomal formulation prepared by the scCO2 technique which can be further developed towards a novel anticancer drug.

Melanogenesis-Inhibitory and Cytotoxic Activities of Chemical Constituents from the Leaves of Sauropus androgynus L. Merr. (Euphorbiaceae).

A new steroid, 20-hydroxyisofucosterol (stigmasta-5,24(28)-diene-3ß,20ß-diol) (7), along with six known compounds 1 - 6 were isolated from the MeOH extract of the leaves of Sauropus androgynus L. Merr. (Euphorbiaceae). The structure of new steroid was determined by HR-APCI-MS and various NMR techniques in combination with literature data. Subsequently, their anti-inflammatory, cytotoxic activities against five human cell lines, as well as inhibitory activities against the α-MSH induced melanogenesis on the B16 cell line were evaluated. As the results, steroid compounds, 6 and 7 exhibited moderate cytotoxic to HL60, AZ521, SKBR3, and A549 tumor cell lines (IC50 26.9 - 45.1 µm) with high tumor selectivity for A549 relative to WI38 cell lines (SI 2.6 and 3.0, resp.). And, flavonoid compounds, 4 and 5 exhibited superior inhibitory activities against melanogenesis (67.0 - 94.7% melanin content), even with no or low toxicity to the cells (90.1 - 99.6% cell viability) at the concentrations from 10 to 100 µm. Furthermore, Western blot analysis suggested that compound 5 could inhibit melanogenesis by suppressing the protein expressions of MITF, TRP-1, TRP-2, and tyrosinase.

Biological Activities of Phenolics from the Fruits of Phyllanthus emblica L. (Euphorbiaceae).

Seven phenolic compounds, 1 - 7, including a new organic acid gallate, mucic acid 1-ethyl 6-methyl ester 2-O-gallate (7), were isolated from the MeOH extract of the fruits of Phyllanthus emblica L. (Euphorbiaceae). The structures were elucidated on the basis of extensive spectroscopic analysis and comparison with literature data. Upon evaluated for their antioxidant abilities by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays. The inhibitory activities against melanogenesis in B16 melanoma cells induced by α-MSH, as well as cytotoxic activities against four human cancer cell lines were also evaluated. All phenolic compounds, 1 - 7, exhibited potent antioxidant abilities (DPPH: IC50 5.6 - 12.9 µm; ABTS: 0.87 - 8.43 µm Trolox/µm; FRAP: 1.01 - 5.79 µm Fe2+ /µm, respectively). Besides, 5 - 7, also exhibited moderate inhibitory activities against melanogenesis (80.7 - 86.8% melanin content), even with no or low toxicity to the cells (93.5 - 101.6% cell viability) at a high concentration of 100 µm. Compounds 1 - 3 exhibited cytotoxic activity against one or more cell lines (IC50 13.9 - 68.4%), and compound 1 with high tumor selectivity for A549 (SI 3.2).

Transfollicular enhancement of methyl myristate loaded in cationic niosomes incorporated in hair lotion.

Hair lotion containing methyl myristate loaded in cationic niosomes (HL-MMnio) composed of Brij72/cholesterol/DDAB at 7:3:0.65 molar ratio was developed. The remaining percentages of MM loaded in cationic niosomes in hair lotion were higher than free MM in hair lotion of about 1.2 times. The cumulative amounts in porcine skin and the receiver compartment of MM loaded in cationic niosomes incorporated in hair lotion were higher than those of free MM in hair lotion of 1.45 and 1.32 times, respectively. HL-MMnio showed very slightly irritation on rabbit skin, which was disappeared after 4 d. For melanogenesis induction in C57BL/6 mice with aged-induced grey body coat hairs, the highest pigmentation scores of HL-MMnio applied on the dorsal area were observed after 21 days, while hair lotion containing the free MM indicated after 35 days. This study has suggested that HL-MMnio was the high potential formulation for canities treatment.

In vitro anti-aging activities of extracts from leaves of Ma Kiang (Cleistocalyx nervosum var. paniala).

CONTEXT: Cleistocalyx nervosum (DC.) Kosterm. var. paniala (Roxb.) J. Parn. & Chantaran. (Myrtaceae) or Ma Kiang contains high amounts of phenolic compounds. Antioxidant activity of its fruit and seed has been investigated. However, limited available information concerning the biological activities of its leaves has been reported. OBJECTIVE: To investigate the in vitro anti-aging potential of young and old leaves of Ma Kiang. MATERIALS AND METHODS: Ma Kiang leaves were extracted using water, methanol, and chloroform as the solvents by cold (sonication) and hot (boiling) processes. The extracts were determined for total phenolic and flavonoid contents. The extracts (at 0.001-10 mg/ml) were tested for antioxidative and tyrosinase inhibition activities using a colorimetric method. The cytotoxicity of extracts (at 0.0001-1 mg/ml) was determined with human skin fibroblasts. Also, the extracts at 0.001, 0.01, and 0.1 mg/ml which showed no toxicity were tested for MMP-2 inhibition. RESULTS: The cold methanol extract of the old leaves showed the highest total phenolic and flavonoid contents of 511.44 ± 18.23 µg GAE/mg and 262.96 ± 2.98 µg QE/mg, respectively. This extract also gave high free radical scavenging, lipid peroxidation inhibition, and tyrosinase inhibition activities with SC50, IPC50, and IC50 values of 0.02 ± 0.004, 0.23 ± 0.13, and 0.02 ± 0.006 mg/ml, respectively. The extract at 0.1 mg/ml exhibited the highest MMP-2 inhibition of 91.14 ± 1.67%. DISCUSSION AND CONCLUSION: The anti-aging potential of the cold methanol extract from old leaves of Ma Kiang can be further developed as an anti-aging agent.

Physicochemical properties and biological activities of Thai plant mucilages for artificial saliva preparation.

CONTEXT: Plant mucilages can be found in various parts of several Thai plants, which can be used as thickening, moisturizing, and lubricating agents in artificial saliva formulations. OBJECTIVE: The objective of this study was to evaluate the physicochemical properties, biological activity, and cytotoxicity of Thai plant mucilages. MATERIALS AND METHODS: The mucilages from Thai plants were extracted by various processes (temperature and pH variation, microwave oven, steam, and Tris-HCl buffer extraction). The viscosity and the rheology were evaluated using viscometer. Antioxidative activities including DPPH radical scavenging and metal chelating activities were investigated. The mucilages were determined for cytotoxicity on normal human gingival fibroblasts and anti-adherent activity of Streptococcus mutans. RESULTS: Mucilages from Ocimum citriodorum Vis. (Lamiaceae), Artocarpus heterophyllus Lam. (Moraceae), Abelmoschus esculentus (Linn.) Moench. (Malvaceae), and Basella alba Linn. (Basellaceae) exhibited pseudoplastic non-Newtonian rheology. The highest DPPH radical-scavenging and metal-chelating activities were observed in the mucilages from B. alba (microwave, 3 min) and A. esculentus (microwave, 1 min) with the SC50 and MC50 values (50% of scavenging activity and 50% of metal chelating activity, respectively) of 0.71 ± 0.32 and 1.11 ± 0.52 mg/ml, respectively. Most mucilages exhibited no cytotoxicity to normal human gingival fibroblasts. The mucilage from A. esculentus (microwave, 5 min) gave the shortest wetting time of 2.75 ± 0.51 min. The highest S. mutans adhesion inhibition was observed in A. esculentus (pH 11) of 5.39 ± 9.70%. DISCUSSION AND CONCLUSION: This study has indicated the suitable physicochemical and biological properties and the potential application of mucilages from Thai plants for artificial saliva preparation.

Potent anti-proliferative effects against oral and cervical cancers of Thai medicinal plants selected from the Thai/Lanna medicinal plant recipe database "MANOSROI III".

CONTEXT: Thai/Lanna medicinal plant recipes have been used for the treatment of several diseases including oral and cervical cancers. OBJECTIVE: To investigate anti-proliferative activity on human cervical (HeLa) and oral (KB) cancer cell lines of medicinal plants selected from Thai/Lanna medicinal plant recipe database "MANOSROI III". MATERIALS AND METHODS: Twenty-three methanolic plant crude extracts were tested for phytochemicals and anti-proliferative activity on HeLa and KB cell lines for 24 h by the sulforhodamine B (SRB) assay at the doses of 1 × 10(1)-1 × 10(-6 )mg/ml. The nine extracts with the concentrations giving 50% growth inhibition (GI50) lower than 100 µg/ml were further semi-purified by liquid/liquid partition in order to evaluate and enhance the anti-proliferative potency. RESULTS: All extracts contained steroids/triterpenoids, but not xanthones. The methanolic extracts of Gloriosa superba L. (Colchinaceae) root and Albizia chinensis (Osbeck) Merr. (Leguminosae-Mimosoideae) wood gave the highest anti-proliferative activity on HeLa and KB cell lines with the GI50 values of 0.91 (6.0- and 0.31-fold of cisplatin and doxorubicin) and 0.16 µg/ml (28.78- and 82.29-fold of cisplatin and doxorubicin), respectively. Hexane and methanol-water fractions of G. superba exhibited the highest anti-proliferative activity on HeLa and KB cell lines with the GI50 values of 0.15 (37- and 1.9-fold of cisplatin and doxorubicin) and 0.058 µg/ml (77.45- and 221.46-fold of cisplatin and doxorubicin), respectively. DISCUSSION AND CONCLUSION: This study has demonstrated the potential of plants selected from MANOSROI III database especially G. superba and A. chinensis for further development as anti-oral and cervical cancer agents.

BIOASSAY-GUIDED FRACTIONATION AND ANTIHYPERTENSIVE PROPERTIES OF FRACTIONS AND CRUDE EXTRACTS OF PERISTROPHE BICALYCULATA (RETZ) NEES.

Hypertension is an important public health issue in both developed and developing countries due to its high incidence and morbidity. This has motivated researchers especially in developing countries to search for strategies for the treatment using different plant parts. The use of the aqueous decoction of the leaves of Peristiophe bicalyculata in the treatment of hypertension has been documented. This study was designed to carry out a bioassay-guided isolation of the antihypertensive components of the leaves of Peristrophe bicalyculata in L-NAME hypertensive rats, determine the angiotensin-converting enzyme inhibitory activity of the extracts and fractions obtained and identify the constituent(s) present. From our results, L-NAME hypertensive rats given the cold water extract had significantly (p < 0.05) lower mean arterial blood pressure (MABP) with longer duration of action than other extracts. Also, the angiotensin-converting enzyme inhibitory activity of the cold water extract was significantly (p < 0.05) higher than that of other extracts. From the GC-MS analysis of the most effective fraction (fraction 4), P,P,P-triphenyl-imino(triphenyl)phosphorane and andrographolide 2(3H)-furanone were identified among others. The present work demonstrates the hypotensive effect of the cold water extract of Peiistiophe bicalyculata on L-NAME hypertensive rats, which further justifies the folkloric application of extracts of the plant in the management as well as treatment of hypertension.

Limonoids from Azadirachta indica var. siamensis extracts and their cytotoxic and melanogenesis-inhibitory activities.

Six new limonoids, 7-benzoyl-17-epinimbocinol (5), 3-acetyl-7-tigloylnimbidinin (8), 1-isovaleroyl-1-detigloylsalanninolide (15), 2,3-dihydro-3α-methoxynimbolide (16), deacetyl-20,21-epoxy-20,22-dihydro-21-deoxyisonimbinolide (26), and deacetyl-20,21,22,23-tetrahydro-20,22-dihydroxy-21,23-dimethoxynimbin (27), along with 28 known limonoids, 1-4, 6, 7, 9-14, 17-25, and 28-34, and two known flavonoids, 35 and 36, have been isolated from the extracts of bark, leaves, roots, and seeds of Azadirachta indica A. Juss. var. siamensis Valeton (Siamese neem tree; Meliaceae). The structures of the new compounds were elucidated on the basis of extensive spectroscopic analysis and comparison with literature data. All of these compounds were evaluated for their cytotoxic activities against leukemia (HL60), lung (A549), stomach (AZ521), and breast (SK-BR-3) cancer cell lines. Eleven compounds, 1, 2, 4-7, 13, 16, 17, 29, and 30, exhibited potent cytotoxicities against one or more cell lines with IC50 values in the range of 0.1-9.3 µM. Compound 16 induced apoptotic cell death in AZ521 cells upon evaluation of the apoptosis-inducing activity by flow cytometric analysis. Western blot analysis on AZ521 cells revealed that compound 16 activated caspases-3, -8, and -9, while increasing the ratio of Bax/Bcl-2. This suggested that 16 induced apoptosis via both mitochondrial and death receptor pathways in AZ521. In addition, upon evaluation of all compounds against the melanogenesis in B16 melanoma cells induced with α-melanocyte-stimulating hormone (α-MSH), 20 limonoids, i.e., 1-3, 6, 9-11, 18, 19, 21-29, 32, and 34, and two flavonoids, 35 and 36, exhibited melanogenesis-inhibitory activities, with no, or almost no, toxicities to the cells at lower and/or higher concentrations, which were more potent than the reference arbutin, a known melanogenesis inhibitor. Western blot analysis showed that nimbin (18) reduced the protein levels of microphtalmia-associated transcription factor (MITF), tyrosinase, tyrosine-related protein 1 (TRP-1), and TRP-2 mostly in a concentration-dependent manner, indicating that 18 inhibits melanogenesis on a α-MSH-stimulated B16 melanoma cells by, at least in part, inhibiting the expression of MITF, followed by decreasing the expression of tyrosinase, TRP-1, and TRP-2.

Limonoids and flavonoids from the flowers of Azadirachta indica var. siamensis, and their melanogenesis-inhibitory and cytotoxic activities.

A new limonoid, 7-O-acetyl-7-O-debenzoyl-22-hydroxy-21-methoxylimocinin (2), and two new flavonoids, 3'-(3-hydroxy-3-methylbutyl)naringenin (7) and 4'-O-methyllespedezaflavanone C (9), along with nine known compounds, including two limonoids, 1 and 3, and seven flavonoids, 4-6, 8, and 10-12, were isolated from a MeOH extract of the flowers of Azadirachta indica A.Juss. var. siamensis Valeton (Siamese neem tree; Meliaceae). The structures of new compounds were elucidated on the basis of extensive spectroscopic analysis and comparison with literature data. All of these compounds were evaluated for their melanogenesis-inhibitory activities in B16 melanoma cells induced with α-melanocyte-stimulating hormone (α-MSH). Compound 2 (16.9% melanin content at 30 µM), 6-deacetylnimbin (3; 49.6% melanin content at 100 µM), and kaempferide (10; 41.7% melanin content at 10 µM) exhibited inhibitory effects with no, or almost no, toxicity to the cells (81.0-111.7% cell viability). In addition, evaluation of their cytotoxic activities against HL60, A549, AZ521, and SK-BR-3 human cancer cell lines, isoazadironolide (1), 4'-O-methyl-8-prenylnaringenin (5), euchrestaflavanone A (8), 9, and 3-methoxy-3'-prenylnaringenin (12) revealed potent cytotoxicities against one or more cell lines with IC50 values in the range of 4.5-9.9 µM.

Novel application of polioviral capsid: development of a potent and prolonged oral calcitonin using polioviral binding ligand and Tat peptide.

CONTEXT: Poor absorption and proteolytic degradation are major obstacles of orally administered peptide drugs including calcitonin. Cell penetrating peptides (CPPs) and receptor binding ligands are interesting tools for the application in the delivery of these drugs. OBJECTIVE: To investigate the enhancements of in vitro and in vivo salmon calcitonin (sCT) activity by Tat, a trans-activating transcriptional peptide and VP1 peptide (V) from polioviral capsid. MATERIALS AND METHODS: Tat/sCT, V/sCT and V/Tat/sCT mixtures at various molar ratios were prepared and investigated for in vitro and in vivo activities of sCT. RESULTS: Tat could increase in vitro sCT activity both in colon adenocarcinoma (HT-29) and mouth epidermal carcinoma (KB) cells. V/sCT (6:1) showed significant increase of intracellular calcium in HT-29 cells. V/Tat/sCT (6:1:1) gave highest increase of intracellular calcium in both cells. Oral administered Tat/sCT (1:1) showed comparable hypocalcemic effect to sCT injection with prolonged action. V/Tat/sCT (6:1:1) demonstrated hypocalcemic effect at 12 h after administration but no hypocalcemic effect was observed from V/sCT. DISCUSSION: Positive charge from Tat might facilitate sCT uptake and absorption. Increasing of intracellular calcium in HT-29 cells by V but lacking of hypocalcemic effect from V/sCT in mice indicated the ligand-receptor mediated delivery of sCT by the interaction between V and PVR. CONCLUSION: Potential application of V and Tat in oral calcitonin delivery system was demonstrated. Further study in a proper PVR bearing host is still needed to provide more useful information for the application of V in the development of drug delivery systems.

Biological activities of fructooligosaccharide (FOS)-containing Coix lachryma-jobi Linn. extract.

Fructooligosaccharide (FOS), a prebiotic was extracted from the grain of Coix lachryma-jobi Linn. (Job's tears) by hot water extraction at 60 °C for 1 h. The resulting dried powder extract was assayed for FOS content of 1-kestose (GF2), nystose (GF3) and 1-ß-D-fructofuranosylnystose (GF4) using HPLC equipped with RI detector. Total FOS content of the extract was 24.98 ± 7.48% (g/100 g crude extract). The biological activity including antioxidant and cytotoxicity of the FOS-containing extract was determined. The antioxidant activity by DPPH free radical scavenging of FOS-containing extract was comparable to vitamin C (0.97 fold of vitamin C) with a slight lipid peroxidation inhibition activity. The extract exhibited no cytotoxic effect on normal human skin fibroblast. These results have confirmed not only the source of FOS from Job's tears extract but also its potential application as antioxidant in food or cosmetic products.

Cancer chemopreventive effect of bergenin from Peltophorum pterocarpum wood.

The aqueous extract of Peltophorum pterocarpum (Fabaceae) wood exhibited potent inhibitory effects against EpsteinBarr virus early antigen (EBV-EA) activation induced with 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells and against melanogenesis in α-melanocyte-stimulating hormone (α-MSH)-stimulated B16 melanoma cells, as well as potent 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging activity. Two phenolic acid derivatives, bergenin (1) and gallic acid (2), were isolated from the ethyl acetate (AcOEt)-soluble fraction obtained from the extract. Compound 1 exhibited potent inhibitory effect against EBV-EA activation and against skin tumor promotion in an in vivo two-stage mouse skin carcinogenesis test based on 7,12-dimethylbenz[a]anthracene (DMBA) as initiator, and with TPA as promoter. Both compounds 1 and 2 exhibited melanogenesis-inhibitory activities in α-MSH-stimulated B16 melanoma cells, and, in addition, compound 2 showed strong DPPH radical-scavenging activity.

Biological activities of phenolic compounds and triterpenoids from the galls of Terminalia chebula.

Nine phenolic compounds, including two phenolic carboxylic acids, 1 and 2, seven hydrolyzable tannins, 3-9, eight triterpenoids, including four oleanane-type triterpene acids, 10-13, and four of their glucosides, 14-17, isolated from a MeOH extract of the gall of Terminalia chebula Retz. (myrobalan tree; Combretaceae), were evaluated for their inhibitory activities against melanogenesis in B16 melanoma cells induced by α-melanocyte-stimulating hormone (α-MSH), against the Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol 13-acetate (TPA) in Raji cells, and against TPA-induced inflammation in mice. Their 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activities and cytotoxic activities against four human cancer cell lines were also evaluated. Compounds 6-9 and 12 exhibited potent inhibitory activities against melanogenesis (39.3-66.3% melanin content) with low toxicity to the cells (74.5-105.9% cell viability) at a concentration of 10 µM. Western-blot analysis revealed that isoterchebulin (8) reduced the protein levels of MITF (=microphtalmia-associated transcription factor), tyrosinase, and TRP-1 (=tyrosine-related protein 1), mostly in a concentration-dependent manner. Eight triterpenoids, 10-17, showed potent inhibitory effects on EBV-EA induction with the IC50 values in the range of 269-363 mol ratio/32 pmol TPA, while these compounds exhibited no DPPH scavenging activities (IC50 >100 µM). On the other hand, the nine phenolic compounds, 1-9, exhibited potent radical-scavenging activities (IC50 1.4-10.9 µM) with weak inhibitory effects on EBV-EA induction (IC50 460-518 mol ratio/32 pmol TPA). The tannin 6 and seven triterpenoids, 10-16, have been shown to inhibit TPA-induced inflammation (1 µg/ear) in mice with the ID50 values in the range of 0.06-0.33 µmol/ear. Arjungenin (10) exhibited inhibitory effect on skin-tumor promotion in an in vivo two-stage mouse-skin carcinogenesis test based on 7,12-dimethylbenz[a]anthracene (DMBA) as initiator and with TPA as promoter. Compounds 1, 2, 4, 5, 7-9, 12, and 13, against HL60 cell line, compounds 1 and 4, against AZ521 cell line, and compounds 1, 11, and 12, against SK-BR-3 cell line, showed moderate cytotoxic activities (IC50 13.9-73.2 µM).

Transdermal absorption and stability enhancement of salmon calcitonin by Tat peptide.

CONTEXT: Highly organized structure of stratum corneum (SC) is the major barrier of the delivery of macromolecules such as proteins and peptides across the skin. Recently, cell penetrating peptides (CPPs) such as HIV1-trans-activating transcriptional (Tat) have been used to enhance the topical delivery of proteins and peptides. OBJECTIVE: This study aimed to enhance the transdermal absorption and chemical stability of salmon calcitonin (sCT) by co-incubation with Tat. MATERIALS AND METHODS: Tat-sCT mixture at 1:1 molar ratio was prepared. Transdermal absorption and chemical stability of the mixture was evaluated in comparing with free sCT. RESULTS: Tat-sCT mixture gave higher cumulative amounts and fluxes of sCT than free sCT. The maximum percentage of sCT of 58.36 ± 12.33% permeated into the receiving chamber was found in Tat-sCT mixture at 6 h which was 3.50 folds of free sCT. Tat-sCT mixture demonstrated better sCT stability than sCT solution after 1 month storage at 4°C, 25°C and 45°C. DISCUSSION: The positively-charged arginine groups in Tat might be responsible for the binding of peptide complexes to negatively charged cell surfaces by electrostatic interactions and also the translocation of sCT through the excised skin. CONCLUSION: This study demonstrated the enhancements of transdermal absorption and stability of sCT by Tat peptide with potential for further application in transdermal delivery of other therapeutic peptides.

Anti-proliferative and matrix metalloproteinase-2 inhibition of Longkong (Lansium domesticum) extracts on human mouth epidermal carcinoma.

CONTEXT: Longkong [Lansium domesticum Corr. (Meliaceae)] is a popular tropical plant producing economic edible fruits found mainly in Southeast Asia. However, limited information is available concerning anticancer activity of Longkong. OBJECTIVE: To investigate anticancer activities in human mouth epidermal carcinoma (KB) of Longkong extracts. MATERIALS AND METHODS: Various parts of Longkong which was collected from Northern and Eastern of Thailand were extracted by the hot and cold processes using water, chloroform, and methanol. The extracts were tested for anti-oxidative activities and anti-proliferation as well as matrix metalloproteinase inhibition on KB cells. RESULTS: The hot water extract of seeds from Northern region (NSEWH), the cold water extract of old leaves from Northern region (NOLWC), and the hot chloroform extract of young leaves from Eastern region (EYLCH) showed the highest free radical scavenging, metal ion chelating, and lipid peroxidation inhibition with SC50, MC50 and IPC50 values of 0.34 ± 0.03, 0.47 ± 1.60 and 0.86 ± 0.31 mg/ml, respectively. The hot and cold chloroform extract of young fruits from Northern region (NYFCH and NYFCC) exhibited anti-proliferation effect against KB cells with IC50 values of 603.45 ± 55.35 and 765.06 ± 46.19 mg/ml, respectively. NYFCC exhibited the highest pro- and active MMP-2 inhibition at 53.03 ± 2.65 and 31.30 ± 0.43%, more than all tested standard anticancer drugs except cisplatin. DISCUSSION AND CONCLUSION: The cold chloroform extract of young fruits from Northern region appeared to contain anticancer active compounds against KB cells because of its high anti-proliferation and MMP-2 inhibition activities.

Potent antihypertensive activity of Thai-Lanna medicinal plants and recipes from "MANOSROI III" database.

CONTEXT: Traditional medicines have long been used by Thai practitioners for the treatment of many diseases including hypertension. The antihypertensive recipes and plants were searched and selected by a computer program from Thai/Lanna medicinal plant recipe database "MANOSROI III" using hypertensive symptoms as keywords. OBJECTIVES: To evaluate the antihypertensive potential of 30 recipes and 10 Thai-Lanna medicinal plants selected from "MANOSROI III" database using l-NAME induced hypertensive rat model. MATERIALS AND METHODS: Extracts from the selected recipes and plants were prepared according to the traditional indications. Antihypertensive activities including the decrease of the mean arterial blood pressure (MABP) and heart rate (HR) of the extracts as well as duration of action were investigated by intra-arterial assessment technique. All extracts were screened for phytochemicals including anthraquinone, glycoside, xanthone, tannin, carotenoid, flavones and alkaloids using standard methods. RESULTS AND CONCLUSIONS: All 12 of the 30 selected recipes (40%) demonstrated antihypertensive activity with the maximum decrease of MABP at 27.17 ± 3.17% that was 2.41-fold of prazosin hydrochloride. Most recipes exhibiting antihypertensive activity contained plants in the families of Zingiberaceae and Piperaceae. The top five antihypertensive recipes showed the presence of glycosides, xanthones and alkaloids. Ten single plants from these recipes were extracted and evaluated for antihypertensive activity. The cassumunar ginger extract exhibited the maximum decrease of MABP at 39.83 ± 3.92%, which was 3.54-times that of prazosin hydrochloride. This study demonstrated the potent antihypertensive activity of Thai medicinal plants and recipes that can be further developed as antihypertensive agents.

Nanoscale gelatinase A (MMP-2) inhibition on human skin fibroblasts of Longkong (Lansium domesticum Correa) leaf extracts for anti-aging.

Leaves of Longkong which collected from Chantaburi in Thailand were extracted by the hot and cold processes using three different solvents including water, chloroform and methanol. The crude extracts were tested for antioxidative activities, tyrosinase inhibition and in vitro cytotoxicity as well as the MMP-2 inhibition activity on human skin fibroblasts for anti-aging evaluation. The hot water crude extract showed the highest antioxidative activities (DPPH radical scavenging, metal ion chelating and lipid peroxidation inhibition) with the SC50, CC50 and IPC50 values of 5.40 +/- 1.23, 32.31 +/- 0.84 and 3.29 +/- 0.30 mg/ml, respectively, and the highest tyrosinase inhibition activity with the IC50 value of 0.49 +/- 0.23 mg/ml. The extract also showed no cytotoxicity on human skin fibroblasts with the cell viability of 80.52 +/- 15.16%. It demonstrated the anti-aging potential by having the pro and active MMP-2 inhibition activity, but lower than ascorbic acid of 1.28 and 1.12 times, respectively. The semi-purified extracts were prepared from this crude extract by solvent-solvent partition. The ethyl acetate soluble fraction showed higher activities (DPPH radical scavenging, metal ion chelating and tyrosinase inhibition) than the crude extract of 23.48, 71.80 and 2.58 times, respectively. This fraction exhibited similar pro and active MMP-2 inhibitory effect to the crude extract. The results from this study have indicated the possible application of the ethyl acetate fraction of the hot water crude extract from leaves of Longkong to be developed as an anti-aging product.