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.

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.

Assessment of the efficacy of a new complex antisensitive skin cream.

BACKGROUND: Sensitive skin is frequently complaint in dermatology consultation with cutaneous manifestations such as stinging, redness, dryness, and burning sensation that affect the quality of life. Its pathogenesis is mainly related to dysfunction of neurosensory, skin barrier, and also immune activity. The treatment is generally based on continuous and topical therapy by nonirritating complex. OBJECTIVE: To evaluate the antisensitive function of a new complex cream composed by Yunnan Portulaca oleracea extract, Prinsepia utilis oil, beta-glucan, and sodium hyaluronate extracted from mushroom. METHODS: A randomized double-blind and self-control study was conducted on 20 selected volunteers with sensitive skin. Subjects applied the test cream to 1 side of the face, and the control cream (tolerance-extreme cream) to the other side of the face, twice daily over 28 days. Evaluations were performed at baseline and at 28 days. Expert clinical grading of facial skin including dryness, roughness, desquamation, and erythema was assessed. Subject self-assessment questionnaires, digital photography and noninvasive bioinstrumentation of hydration, transepidermal water loss, lipid index, skin texture, and wettability were also included in the study. RESULTS: Products were well tolerated. For all parameters studied, no significant difference was observed between test and control creams. Results showed that test cream provided a statistically significant improvement in clinical grading scores for dryness, roughness, and erythema at 28 days compared to baseline. In addition, statistically significant improvement of skin hydration and texture parameters (eg, smoothness and roughness) was demonstrated. Volunteers' questionnaire revealed self-perceived benefits consistent with expert visual grading. CONCLUSION: This study confirmed the effectiveness and tolerance of the new complex cream in subjects with sensitive skin. The test cream could serve as a daily care moisturizer for face.

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.

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.

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.