Anti-Melanogenesis Activity of Crocodile (Crocodylus siamensis) White Blood Cell Extract on Ultraviolet B-Irradiated Melanocytes.

Ultraviolet (UV) radiation generates a range of biological effects in the skin, which includes premature skin aging, hyperpigmentation, and cancer. Therefore, the development of new effective agents for UV-related skin damage remains a challenge in the pharmaceutical industry. This study aims to test the inhibitory effect of crocodile white blood cell (cWBC) extract, a rich source of bioactive peptides, on ultraviolet B (UVB)-induced melanocyte pigmentation. The results showed that cWBC (6.25-400 µg/mL) could inhibit tyrosinase without adduct formation by 12.97 ± 4.20% on average. cWBC pretreatment (25-100 µg/mL) had no cytotoxicity and reduced intracellular melanin to 111.17 ± 5.20% compared with 124.87 ± 7.43 for UVB condition. The protective role of cWBC pretreatment against UVB was exhibited by the promotion of cell proliferation and the prevention of UVB-induced morphological change as observed from F actin staining. The decrease of microphthalmia-associated transcription factor expression levels after cWBC pretreatment might be a mechanism by which cWBC suppresses UVB-induced pigmentation. These results suggest that cWBC could be beneficial for the prevention of UVB-induced skin pigmentation.

Evaluation of the safety and healing potential of a fibroin-aloe gel film for the treatment of diabetic foot ulcers.

OBJECTIVE: This study aimed to develop a wound dressing prepared from the blending of silkworm fibroin and aloe gel extract for use in the treatment of diabetic foot ulcers (DFUs). METHODS: Fibroin extracted from silkworm cocoons and aloe gel extract were dissolved in deionised water. pH levels were then adjusted with lactic acid solution. A simple casting technique was used to obtain the fibroin-aloe gel film. The surface morphology, hardness, flexibility and infrared spectrum of the sterilised film were tested. Swelling ratio was measured from changes in weight. The cytocompatibility of the film to human dermal fibroblast was determined using XTT assay. Hard-to-heal DFUs (grade I Wagner score) were treated with the film for four weeks. The application site was assessed for allergic reactions and/or sensitisation. Wound size was measured using standardised digital photography. RESULTS: A total of five hard-to-heal DFUs were treated. The obtained film sterilised with ozonation showed a non-porous structure. The elongation at break and tensile strength of the wet film were 9.00±0.95% and 6.89±1.21N, respectively. Fourier-transform infrared spectroscopy data indicated the presence of amides I, II and III, of peptide linkage, which are the chemical characteristics of the fibroin. Functional groups relating to healing activity of the aloe gel extract were also found. The swelling ratio of the film immersed in water for 24 hours was 0.8±0.01. In three DFUs (40-50mm2 in size), a wound area reduction of 0.4-0.8mm2/day was observed and were healed in 2-3 weeks. The remaining two SFUs (500mm2 in size) showed a wound area reduction of 4mm2/day and were almost closed at four weeks. No allergic reaction or infection was observed in any of the wounds. CONCLUSION: The obtained film showed a non-porous structure, and its strength and flexibility were adequate for storage and handling. The film tended to increase the proliferation of fibroblasts. The wound dressing showed potential for accelerating the healing rate of DFUs.

Photoprotective Potential of the Natural Artocarpin against In Vitro UVB-Induced Apoptosis.

Apoptosis, a well-known pattern of programmed cell death, occurs in multicellular organisms not only for controlling tissue homeostasis but also for getting rid of severely damaged cells in order to protect the redundant growth of abnormal cells undergoing cancerous cells. The epidermis of the human skin, composed largely of keratinocytes (KCs), is renewed continuously. Therefore, KCs apoptosis plays a critical role in the maintenance of epidermis structure and function. However, regulated cell death can be disturbed by environmental factors especially ultraviolet radiation (UV) B, leading to the formation of sunburn cells (KCs undergoing UVB-induced apoptosis) and impairing the skin integrity. In the present study, we firstly reported the potential of the natural artocarpin (NAR) to regulate UVB-induced human KCs apoptosis. The NAR showed antilipid peroxidation with an IC50 value of 18.2 ± 1.6 µg/mL, according to TBARS assay while the IC50 value of trolox, a well-known antioxidant, was 7.3 ± 0.8 µg/mL. For cell-based studies, KCs were pretreated with 3.1 µg/mL of the NAR for 24 hr and then exposed to UVB at 55 mJ/cm2. Our data indicated that the NAR pretreatment reduces UVB-induced oxidative stress by scavenging free radicals and nitric oxide and therefore prevents reactive oxygen species (ROS) and reactive nitrogen species- (RNS-) mediated apoptosis. The NAR pretreatment has been shown also to reduce the UVB-induced cyclobutane pyrimidine dimer (CPD) lesions by absorbing UVB radiation and regulating the cell cycle phase. Additionally, the NAR pretreatment was found to modulate the expression of cleaved caspases-3 and 8 that trigger different signalling cascades leading to apoptosis. Thus, these results provide a basis for the investigation of the photoprotective effect of the NAR isolated from A. altilis heartwood and suggest that it can be potentially used as an agent against UVB-induced skin damages.

Evaluation of moisturizing and irritation potential of sacha inchi oil.

OBJECTIVE: The moisturizing and irritation effects of sacha inchi oil were evaluated. STUDY DESIGN: The moisturizing effect on the skin was clinically assessed using a regression study design. Sacha inchi oil or olive oil (benchmark) was applied on the left or right lower leg of the subjects for 14 days followed by application discontinuation for 2 days. The TEWL, skin moisture content and dryness appearance were observed. METHODS: The fatty acid composition and characteristics of cold-pressed sacha inchi seed oil were determined. Skin tissues cultured ex vivo were used to assess primary irritation induced by the oil by examining keratin 1 expression and TNF-α and IL-1α release from the oil-applied tissues. RESULTS: The sacha inchi oil contained 42.3% linolenic acid and 39.5% linoleic acid. This oil's saponification, iodine, acid and peroxide values were 168.58 ± 1.55 mg KOH/g, 203.00 ± 0.04 g I2 /100 g, 1.68 ± 0.03 mg KOH/g, and 1.95 ± 0.26 mEq peroxide/kg, respectively. Compared with nontreated skin tissues, induced secretion of TNF-α and IL-1α and disruption of keratin 1 integrity in the stratum corneum layer were not found in the sacha inchi oil-treated tissues. In a clinical study with 13 volunteers, the improvement in moisture content and skin dryness appearance at the sacha inchi oil-applied site was comparable with that observed at the olive oil-applied site. CONCLUSIONS: The sacha inchi oil was mild to the skin and benefited dry skin.

Artocarpin-enriched (Artocarpus altilis) Heartwood Extract Provides Protection Against UVB-induced Mechanical Damage in Dermal Fibroblasts.

This study aimed to evaluate the protective effect of artocarpin-enriched (Artocarpus altilis) heartwood extract on the mechanical properties of UVB-irradiated fibroblasts. Human skin fibroblasts were pretreated with 50 µg/mL-1 extract and later irradiated with UVB (200 mJ/cm-2 ). They were then cultured within three-dimensional of free-floating and tense collagen lattices. The pretreatment of fibroblasts with the extract prior to UVB radiation showed cells protection against UVB-induced suppression of α-SMA expression, fibroblast migration and contraction. These results reveal that the extract prevents mechanical damages induced by UVB irradiation in fibroblast-embedded collagen lattices, and therefore, has a potential as a natural photo-protectant.

Phenanthrenes from Eulophia macrobulbon as Novel Phosphodiesterase-5 Inhibitors.

Phosphodiesterase 5 (PDE5) inhibitors can be used for the treatment of erectile dysfunction and pulmonary hypertension. In order to search for new leads of PDE5 inhibitors, we investigated the chemical constituents of the tubers of Eulophia macrobulbon (E.C. Parish & Rchb. f.) Hook. f. A new phenanthrene, 9,10-dihydro-4-(4'-hydroxybenzyl)-2,5-dimethoxyphenanthrene-1,7-dio (1) and three known phenanthrenes i.e., 1-(4'-hydroxybenzyl)-4,8- dimethoxyphenanthrene-2,7-diol (2), (9,10-dihydro-2,5-dimethoxyphenanthrene-1,7-diol (3) and 1,5,7-trimethoxyphenanthrene-2,6-diol). (4) were isolated Among these, 2 was the most potent PDE5 inhibitor (IC50 =1.67±0.54 µM) evaluated by the [3H]cGMP radioassay method, whereas 1 showed mild activity (IC50 = 62.3±3.3 µM). Their inhibitory selectivities against PDE5 over PDE6 were also studied. This study suggests phenanthrenes as a new class of PDE5 inhibitors.

Formulation of chitosan patch incorporating Artocarpus altilis heartwood extract for improving hyperpigmentation.

Artocarpus altilis heartwood extract contains the bioactive compound artocarpin which exhibits melanogenesis inhibitory activity. However, the extract has poor solubility which affects the skin permeability of the compound. A chitosan hydrogel patch incorporating A. altilis heartwood extract was formulated to enhance the delivery of an amount of artocarpin sufficient for depigmenting the skin. The extract was prepared as an o/w microemulsion before blending with an aqueous solution of chitosan. The hydrogel patch was formulated by blending in a 1:1 ratio by weight of 4% w/w chitosan solution and 0.04% w/w extract microemulsion which provides optimal values of the mechanical properties of the patch. The release of artocarpin from the formulated patch (artocarpin content, 0.07 mg/cm2) exhibited two phases; the rapid rate (0-15 min) averaged 0.73 µg/min/mm2, and the slow rate (15-240 min) averaged 0.02 µg/min/mm2. The formulated patches significantly improved the hyperpigmented area of the subjects after 3 weeks of application. No adverse events were observed. The results indicate that the formulated chitosan hydrogel patch delivers an effective amount of incorporated artocarpin depigmenting action.

Ethanol extract of Terminalia chebula fruit protects against UVB-induced skin damage.

CONTEXT: The fruit of Terminalia chebula Retz. (Combretaceae) has been used for several therapeutic purposes in Thai folk medicines. Currently, the ethanol extracts containing antioxidant compounds have shown the ability to promote collagen synthesis. OBJECTIVE: This purpose of this work was to study the effects of the ethanol extract from T. chebula fruit on the inhibition of cutaneous photodamage. MATERIALS AND METHODS: The viability of human skin fibroblasts after incubation with T. chebula at concentration 0.5-50 µg/mL for 24, 48 and 72 h was assessed by using sodium 3'-[(phenyl-amino)-carbonyl]-3,4,tetrazolium-bis(4-methoxy-6-notro)benzene-sulphonic acid hydrate (XTT). The levels of type I procollagen and matrix metalloproteinases (MMP)-1 and MMP-13 produced by UVB-irradiated fibroblasts were determined by ELISA. Skin thickness and collagen content caused by long-term UVB irradiation in male ICR mice were determined from haematoxylin and eosin stained tissue sections and spectrophotometric measurement of hydroxyproline. RESULTS: The extract (0.5-50 µg/mL) had no effect on cell viability or morphology of the human fibroblasts. In vitro studies showed that the T. chebula extract reduced the UVB-induced MMP-1 and MMP-13 expression, whereas an increased production of type I procollagen was observed. In a UVB-irradiated animal model, male ICR mice with hair shaved were chronically exposed to UVB which lead to epidermal thickness and loss of hydroxyproline. However, these effects were fully prevented by the topical application of the T. chebula ethanol extract. DISCUSSION AND CONCLUSION: These data suggested that the T. chebula ethanol fruit extract is an efficacious pharmaceutical protectant of skin against photodamage.

Artocarpus altilis heartwood extract protects skin against UVB in vitro and in vivo.

ETHNOPHARMACOLOGICAL RELEVANCE: Artocarpus altilis (Moreceae) has been widely used as a traditional folk medicine in Southeast Asia for the treatment of many diseases, including skin disorders, such as ulcers and dermatitis. AIM OF THE STUDY: The present study aimed to investigate the ability of an artocarpin-enriched extract to prevent ultraviolet radiation B-induced photodamage. MATERIALS AND METHODS: The content of artocarpin in the extract was determined by high performance liquid chromatography (HPLC). A DPPH assay was used to evaluate the free radical scavenging activity of the extract, which was compared with those of l-ascorbic acid and α-tocopherol. Cytotoxicity and proliferation of cells treated with the extract were determined using XTT and BrdU assays, respectively. Human skin fibroblasts and keratinocytes were pretreated with the extract for 24h and later irradiated with ultraviolet radiation B at 128 J/cm(2). The levels of TNF-α and IL-6 released from ultraviolet radiation B-irradiated keratinocytes and, MMP-1 and type-I procollagen produced by ultraviolet radiation B-irradiated fibroblasts were measured by ELISA and/or western blotting. The hairless skin of male mice (outbred ICR) was treated with the extract or l-ascorbic acid solution prior to exposure to ultraviolet radiation B irradiation. The dose of ultraviolet B irradiation was consecutively increased to 18, 36, 54, and 72 J/cm(2) at weeks 1-4, 4-7, 7-10, and 10-12, respectively. The epidermal thickness and collagen content in the skin of ultraviolet radiation B-irradiated mice were evaluated. RESULTS: The extract concentration of 50 µg/mL was not toxic and did not inhibit the proliferation of fibroblasts. The pretreatment of fibroblasts with 50 µg/mL extract prior to ultraviolet radiation B irradiation attenuated MMP-1 production but did not affect type-I procollagen production. The extract also decreased the ultraviolet radiation B-induced production of TNF-α and IL-6 in keratinocytes. Moreover, the topical administration of the extract suppressed epidermal thickening and collagen loss in chronically ultraviolet radiation B-exposed skin in mice. CONCLUSIONS: The experimental study revealed that A. altilis extract suppresses structural alterations in skin damaged by ultraviolet radiation B irradiation. This suppression was, at least partially, mediated by decrease in MMP-1 production in fibroblasts and TNF-α and IL-6 productions in keratinocytes.

Preventive effects of tamarind seed coat extract on UVA-induced alterations in human skin fibroblasts.

One of the most damaging actions on skin is from solar radiation, particularly from its ultraviolet (UV) component, through the formation of oxidative species. Thus, an antioxidant strategy that prevents the formation of these oxidants could form the basis of an efficacious cutaneous protectant. Many herbal materials contain antioxidant polyphenols, and this study assessed the possibility that tamarind seed coat extract could fulfill this role. An alcoholic extract of the tamarind (Tamarindus indica L.) seed coat showed stronger antioxidant activity (2,2-diphenyl-1-picrylhydrazyl inhibition, EC(50) = 12.9 µg/ml) than L-ascorbic acid (EC(50) = 22.9 µg/ml) and α-tocopherol (EC(50) = 29.3 µg/ml). In cultured fibroblasts taken from human skin, hydrogen peroxide (100-1000 µM) damaged 62-92% of the cells compared to only 35-47% when the cells were preincubated in extract (200 µg/ml) for 24 h. UVA (40 J/cm2) irradiation of human fibroblasts damaged 25% of the cells but the death rate was reduced to 10% with extract. UV irradiation increased the proportion of cells arrest in G(0)/G(1) phase (from 59% to 78%) but this was largely prevented by the extract (64%), according to flow cytometry. Intracellular total glutathione of UVA-irradiated cells pretreated with the extract increased to 10-25% compared to the non-pretreated group at 24-72 h after irradiation. Fibroblasts typically increased matrix metalloproteinase-1 secretion after photodamage, and this is prevented by the extract. This is the first report showing that tamarind seed coat extract is an antioxidant and can protect human skin fibroblasts from cellular damage produced by UVA and thus may form the foundation for an antiaging cosmetic.

Effects of Thai Musa species on prevention of UVB-induced skin damage in mice.

The effects of oral administration of Musa sapientum and Musa suerier on prevention of UVB induced skin damages were investigated in male ICR mice. Animals were orally administered 50mg/day ascorbic acid, or M. sapientum or M. suerier's fruit pulps at dose of 0.5, 1 or 1.5 mg/g body weight/day for 12 weeks. Concurrently, the shaved backs of animals were irradiated with UVB for 12weeks. The intensity of irradiation was progressively increased, from 54 mJ/cm(2) per exposure at week 1-126 mJ/cm(2) at week 11. A significant decrease (p<0.05) in skin elasticity (from 0.82±0.02 to 0.42±0.09) and total glutathione (from (193.6±18.7 to 152.7±7.8 ng/mg protein) as compared with the control group (water-administered UVB-irradiated mice) was observed after 12 weeks of UVB exposure. When L-ascorbic acid (0.72±0.01) or 1mg/g body weight/day M. suerier (0.84±0.06) were administered to UVB-irradiated mice, the reduction in skin elasticity was significantly inhibited (p<0.05). Moreover, the significant increase (p<0.05) in level of total glutathione was found in these groups (220.8±13.3 ng/mg protein for l-ascorbic acid and 224.9±20.1 ng/mg protein for M. suerier). These findings suggest the potential effect of daily consumption of M. suerier on prevention of skin damage from repeated UVB exposure.

Effects of the blended fibroin/aloe gel film on wound healing in streptozotocin-induced diabetic rats.

Delayed healing remains a major clinical problem and here we have sought to develop an improved dressing film comprising 1.95% w/v fibroin and 0.05% w/v aloe gel extract. The tensile strength of dry film was 21.1 ± 0.5 MPa and broke at 1.1 ± 0.2% elongation; corresponding values for wet film were 18.3 ± 1.3 MPa and 1.9 ± 0.1%. The film maintained its shape upon water immersion and the swelling ratio of the dry film was 0.8 ± 0.1 while the water uptake was 43.7 ± 2.6%. After 28 days of incubation in phosphate buffered saline (1 M, pH 7.4, 37 °C), the weight of film was reduced by 6.7 ± 1.1% and the tensile strength and elongation at breaking point (dry state) were 15.4 ± 0.6 MPa and 1.5 ± 0.2%, respectively. Compared to aloe-free fibroin film (2.0% fibroin extract only), the blended film enhanced the attachment and proliferation of skin fibroblasts. The bFGF immunofluorescence of fibroblasts cultured on the blended film appeared greater than those cultured on tissue culture plate or on aloe-free fibroin film while α-smooth muscle actin was maintained. In streptozotocin-induced diabetic rats, the wounds dressed with the blended film were smaller (p <0.05) by day 7 after wounding, compared to untreated diabetic wounds. Histology of repaired diabetic wounds showed the fibroblast distribution and collagen fiber organization to be similar to wounds in normal rats, and this was matched by enhanced hydroxyproline content. Thus, such accelerated wound healing by the blended fibroin/aloe gel films may find application in treatment of diabetic non-healing skin ulcers.

Kaempferia parviflora, a plant used in traditional medicine to enhance sexual performance contains large amounts of low affinity PDE5 inhibitors.

AIM OF THE STUDY: A number of medicinal plants are used in traditional medicine to treat erectile dysfunction. Since cyclic nucleotide PDEs inhibitors underlie several current treatments for this condition, we sought to show whether these plants might contain substantial amounts of PDE5 inhibitors. MATERIALS AND METHODS: Forty one plant extracts and eight 7-methoxyflavones from Kaempferia parviflora Wall. ex Baker were screened for PDE5 and PDE6 inhibitory activities using the two-step radioactive assay. The PDE5 and PDE6 were prepared from mice lung and chicken retinas, respectively. All plant extracts were tested at 50 µg/ml whereas the pure compounds were tested at 10 µM. RESULTS: From forty one plant extracts tested, four showed the PDE5 inhibitory effect. The chemical constituents isolated from rhizomes of Kaempferia parviflora were further investigated on inhibitory activity against PDE5 and PDE6. The results showed that 7-methoxyflavones from this plant showed inhibition toward both enzymes. The most potent PDE5 inhibitor was 5,7-dimethoxyflavone (IC(50) = 10.64 ± 2.09 µM, selectivity on PDE5 over PDE6 = 3.71). Structure activity relationship showed that the methoxyl group at C-5 position of 7-methoxyflavones was necessary for PDE5 inhibition. CONCLUSIONS: Kaempferia parviflora rhizome extract and its 7-methoxyflavone constituents had moderate inhibitory activity against PDE5. This finding provides an explanation for enhancing sexual performance in the traditional use of Kaempferia parviflora. Moreover, 5,7-dimethoxyflavones should make a useful lead compound to further develop clinically efficacious PDE5 inhibitors.

Depigmenting action of a nanoemulsion containing heartwood extract of Artocarpus incisus on UVB-induced hyperpigmentation in C57BL/6 mice.

Melasma hyperpigmentation is an acquired disorder predominantly affecting the female population. The present study was conducted to determine the potential of a botanical extract to reduce observable hyperpigmentation. The extract from heartwood of Artocarpus incisus was formulated into nanoemulsions, and the depigmenting efficacy of the formulated nanoemulsion was determined in vivo. HPLC analysis showed that the extract contained artocarpin in an amount of 44.5 ± 0.1% w/w. The extract exhibited melanogenesis inhibition with an IC(50) value of 30.2 ± 2.4 mg/ml, while kojic acid, a well known lightening agent, exhibited an IC(50) of 51.4 ± 5.1 mg/ml. The nanoemulsion containing the extract was then formulated and prepared by the phase inversion technique. The concentration of the extract used was about six times its IC(50). The optimal formula containing 0.02% w/w extract, 41.6% w/w isopropyl myristate, 0.03% w/w α-tocopherol, 5% w/wglyc-eryl monostearate (co-emulsifier), 8% w/w ceteareth-10 (emulsifier), 0.05% triethanolamine, 0.03% w/w carbopol 940, and water adjusted to 100% w/w provided a homogeneous o/w emulsion with a droplet size of 325 ± 15 nm and a polydispersity of 0.31 ± 0.02. The depigmenting efficacy was then observed following topical application of the formulated nanoemulsion to UVB-stimulated hyperpigmented dorsal skin of C57BL/6 mice. A strongly visible decrease in hyperpigmentation was observed after six weeks of treatment with the formulated nanoemulsion. The degree of pigmentation decreased after the application was 84 ± 4 units, while that after the application of the extracted prepared into solution was 51 ± 3 units. The applied areas would return to their original color after treatment was stopped for four weeks.

Evaluation of the effect of Thai breadfruit's heartwood extract on the biological functions of fibroblasts from wrinkles.

In previous studies, extract from Artocarpus incisus's heartwood (breadfruit tree) had antioxidant and antimelanogenic activities. Here, we investigated the extract's action on facial skin fibroblasts from wrinkled skin and nonwrinkled skin biopsies, particularly in the production of type I procollagen and metalloproteinase- 1 (MMP-1) and in the reorganization of collagen fibers. We found that the extract at a concentration of 50 microg/ml significantly enhanced percent viability and proliferation of wrinkled-skin fibroblasts. Flow cytometry showed that a 3.6-fold increased proportion of the wrinkled-skin fibroblasts were in their cell cycle S-phase, indicating increased proliferation. Type I procollagen synthesis by wrinkled-skin fibroblasts was augmented by the extract. Nonwrinkled-skin fibroblasts had higher synthesis and were unaffected by the extract. MMP-1 secretion was greater for wrinkled-skin fibroblasts, but the extract decreased its secretion for both fi broblasts samples. Fibroblasts were incorporated in collagen lattice disks. Lattices with nonwrinkled-skin fibroblasts contracted uniformly by 56% after a three-day culture and the extract had little effect. However, wrinkled-skin fi broblast lattices failed to show appreciable contractions (to 12% after three days). But remarkably, the extract conferred an ability of the wrinkled-skin fibroblast lattices to fully contract (to 53%). This shows that wrinkled-skin fi broblasts have the ability to reorganize collagen but that the extract can reactivate this latent potential. Our findings for the first time reveal that A. incisus's heartwood extract reversed the fibroblast deficiencies in the metabolism and reorganization of collagen and may underlie a wrinkle treatment.

Effects of trans-4-(aminomethyl) cyclohexanecarboxylic acid/potassium azeloyl diglycinate/niacinamide topical emulsion in Thai adults with melasma: a single-center, randomized, double-blind, controlled study.

BACKGROUND: Melasma is an acquired hyperpigmentary disorder characterized by dark patches or macules located on the cheeks, forehead, upper lip, chin, and neck. Treatment of melasma involves the use of topical hypopigmenting agents such as hydroquinone, tretinoin, and azelaic acid and its derivatives. OBJECTIVE: The purpose of this study was to assess the efficacy of a formulation containing a combination of trans-4-(aminomethyl) cyclohexanecarboxylic acid/potassium azeloyl diglycinate/niacinamide compared with an emulsion-based control in the treatment of melasma in Thai adults. METHODS: In this single-center, randomized, double-blind, controlled study, Thai patients with mild to moderate facial melasma (relative melanin value [RMV] in range of 20-120) were randomized for the application of either the test or the emulsion-based (control) product in the morning and before bedtime for 8 weeks. The supplemental sunscreen product with sun protection factor 30 was distributed to all patients. Subjects were assessed for the intensity of their hyperpigmented skin area by measuring the difference in the absolute melanin value between hyperpigmented skin and normal skin (RMV). This parameter was used as a primary outcome of this study. Additionally, the severity of melasma was determined visually using the Melasma Area and Severity Index (MASI) scored independently by 3 investigators. The assessments of melasma intensity and other skin properties were performed before administration (week 0) and every 2 weeks thereafter for up to 8 weeks. Other skin properties, including moisture content, pH, and redness (erythema value), were measured. Adverse events (AEs), including erythema, scaling, and edema, were also assessed by a dermatologist using the visual grading scale of Frosch and Kligman and COLIPA. RESULTS: The resulting primary intent-to-treat (ITT) population included 33 patients in the test group and 34 patients in the control group. Sixty patients completed all 8 weeks of the study (on-treatment [OT] population): 91% (30) of the 33 patients in the test group, and 88% (30) of the 34 patients in the control group. Between-group differences in mean RMV were statistically significant at week 6 in both the primary ITT (P = 0.005) and OT (P = 0.006) populations. The significant differences in mean MASI scores between the test and the control groups were initially observed at weeks 4 (P = 0.005) and 8 (P = 0.027) in the OT and primary ITT populations, respectively. Other parameters, including skin pH, erythema, and moisture content did not significantly change from baseline at any time point of study. The incidence of AEs was not different between the test (4/33 [12%]) and control (5/34 [15%]) groups. CONCLUSIONS: The significant differences in RMVs between the test and control groups were observed after 6 weeks of treatment, both in the primary ITT and OT populations. The incidence of patients with AEs was not significantly different between the test and control groups.

Screening for phosphodiesterase inhibitory activity of Thai medicinal plants.

INTRODUCTION: Phosphodiesterases (PDEs) are a group of enzymes that have powerful effects on cellular signaling because they regulate the second messenger, cAMP or cGMP. PDE inhibitors have been used for treatment of many indications such as cardiovascular diseases, chronic obstructive pulmonary diseases, erectile dysfunction and pulmonary hypertension. THE AIM OF THE STUDY: The aim of the study was to search for sources of PDE inhibitors from Thai biodiversity. MATERIALS AND METHODS: Some Thai medicinal plants used as aphrodisiac and neurotonic agents together with plants from Leguminosae collected from the North of Thailand were screened for PDE inhibitory activity using a radioassay. RESULTS: Seven from nineteen aphrodisiac and neurotonic plants as well as three from twelve Leguminosae plants showed potent PDEs inhibitory activity. The concentrations that could inhibit 50% PDE activity (IC(50)) of the active extracts were determined in comparison to the standard inhibitor, 3-isobutyl-1-methylxanthine (IBMX). Betula alnoides, Hiptage benghalensis, Leea indica and Senna surrattensis showed IC(50) values in the range of microgram per milliliter while IBMX standard showed an IC(50) value of 0.68+/-0.13 microg/ml. CONCLUSION: Thai biodiversity was the great sources of PDE inhibitors.

Evaluation of the effect of Thai breadfruit's heartwood extract on melanogenesis-inhibitory and antioxidation activities.

The aim of this study was to clarify the melanogenesis-inhibitory and antioxidant activity of Thai breadfruit's heartwood extract for application as a skin-lightening agent. The heartwood of breadfruit (Artocarpus incisus ) grown in Phitsanulok Province, Thailand, was extracted by using diethyl ether or methanol. The amount of artocarpin, a major component of A. incisus extract, was determined by using the HPLC method. The artocarpin content found in ether extract was 45.19 +/- 0.45% w/w, whereas that in methanol extract was 19.61 +/- 0.05% w/w. The ether extract was then evaluated for tyrosinase-inhibitory, melanogenesis-inhibitory, and antioxidant activities. The tyrosinase-inhibitory activity was tested in vitro by monitoring the inhibition of the extract against the formation of DOPAchrome by tyrosinase enzyme. The results showed that the tyrosinase-inhibitory activity of the extract was in a dose-dependent manner. The obtained IC50 value was 10.26 +/- 3.04 microg/ml, while kojic acid, a well-known tyrosinase inhibitor, provided an IC50 of 7.89 +/- 0.18 microg/ml. Melanocyte B16F1 melanoma cells (ATCC No. CRL-6323) were then used for determination of the melanogenesis-inhibitory activity of the extract, comparing it to hydroquinone, kojic acid, and purified artocarpin. The amount of melanin produced by the cells was monitored by measuring an absorbence at 490 nm. The obtained results indicated that A. incisus extract at a concentration of 2 to 25 microg/ml was able to decrease the melanin production of the melanocyte B16F1 cells. The obtained micrograph also confirmed that the extract did not change the cell morphology but reduced the melanin content by inhibiting melanin synthesis, whereas the purified artocarpin at a concentration of 4.5 microg/ml caused changes in cell morphology. Additionally, the extract exhibited antioxidant activity in a dose-dependent manner at an EC50 of 169.53 +/- 9.73 microg/ml, according to DPPH assay. The obtained results indicated that the ether extract of A. incisus 's heartwood has the potential of acting as a skin-lightening agent for application in cosmetics.

Cleansing lotion containing tamarind fruit pulp extract. II. Study of cumulative irritation effects in human.

BACKGROUND: Cleansing lotion containing extract of tamarind fruit pulp was developed to provide skin a lighter effect. Skin irritation may occur due to keratolytic effect of alpha-hydroxyl acids (AHA) in the tamarind fruit pulp extract. OBJECTIVE: To assess the cumulative irritation effect of cleansing lotion containing tamarind fruit extract with 2% (w/w) tartaric acid on human skin compared with placebo product and de-ionized water. METHODS: The study design was a single-blinded, randomized side of arm, and controlled study. Three samples, including test product, placebo product, and de-ionized water, were repeatedly applied on the inner forearm of 15 healthy females (aged 28.3 +/- 3.1 years) for 30 min daily for 5 days under semi-occlusive patch. Skin irritation was measured by using visual scoring and instruments such as Tewameter and Mexameter. All measurements were done before application of samples every day from day 1 until day 5. Final measurements were done after the last application for 3 days (day 8). RESULTS: The results obtained from the visual scoring scale indicated no irritation signs and symptoms of test product. Mean differences of transepidermal water loss and erythema values between test product and de-ionized water and between test and placebo products were not statistically significant (P > 0.05). CONCLUSIONS: These findings indicate a preliminary safety evidence of our developed cleansing lotion containing the natural AHAs and can be used as cumulative evidence for supporting the future home use study of this product in human.