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.