Low-energy helium-neon lasers (632.8 nm) have been employed in a variety of clinical treatments including vitiligo management. Light-mediated reaction to low-energy laser irradiation is referred to as biostimulation rather than a thermal effect. This study sought to determine the theoretical basis and clinical evidence for the effectiveness of helium-neon lasers in treating vitiligo. Cultured keratinocytes and fibroblasts were irradiated with 0.5-1.5 J per cm2 helium-neon laser radiation. The effects of the helium-neon laser on melanocyte growth and proliferation were investigated. The results of this in vitro study revealed a significant increase in basic fibroblast growth factor release from both keratinocytes and fibroblasts and a significant increase in nerve growth factor release from keratinocytes. Medium from helium-neon laser irradiated keratinocytes stimulated [3H]thymidine uptake and proliferation of cultured melanocytes. Furthermore, melanocyte migration was enhanced either directly by helium-neon laser irradiation or indirectly by the medium derived from helium-neon laser treated keratinocytes. Thirty patients with segmental-type vitiligo on the head and/or neck were enrolled in this study. Helium-neon laser light was administered locally at 3.0 J per cm2 with point stimulation once or twice weekly. The percentage of repigmented area was used for clinical evaluation of effectiveness. After an average of 16 treatment sessions, initial repigmentation was noticed. Marked repigmentation (>50%) was observed in 60% of patients with successive treatments. Basic fibroblast growth factor is a putative melanocyte growth factor, whereas nerve growth factor is a paracrine factor for melanocyte survival in the skin. Both nerve growth factor and basic fibroblast growth factor stimulate melanocyte migration. It is reasonable to propose that helium-neon laser irradiation clearly stimulates melanocyte migration and proliferation and mitogen release for melanocyte growth and may also rescue damaged melanocytes, therefore providing a microenvironment for inducing repigmentation in vitiligo.

Narrow-band ultraviolet-B (UVB) radiation is an effective treatment for vitiligo vulgaris. However, the mechanisms of narrow-band UVB in inducing repigmentation of vitiligo lesions are not thoroughly clarified. The purpose of our study was to investigate the effects of narrow-band UVB irradiation on melanocyte proliferation and migration in vitro. Our results showed that the cell counts as well as [3H]thymidine uptake of melanocytes were significantly enhanced by narrow-band UVB-irradiated keratinocyte supernatants. In these supernatants, a significant increase in basic fibroblast growth factor (bFGF) and in endothelin-1 (ET-1) release was observed. bFGF is a natural mitogen for melanocytes, whereas ET-1 can stimulate DNA synthesis in melanocytes. This stimulatory effect of melanocyte proliferation by supernatants derived from narrow-band UVB-irradiated keratinocytes was significantly reduced by a selective endothelin-B (ET-B) receptor antagonist (BQ788), suggesting an essential role of ET-1 on melanocyte proliferation. Our results of time-lapse microphotography revealed a stimulatory effect of narrow-band UVB irradiation on melanocyte migration. Focal adhesion kinase (FAK) plays a pivotal role in cell migration. Phosphorylated FAK (p125(FAK)) expression on melanocyte was enhanced by narrow-band UVB irradiation. In this study, narrow-band UVB irradiation stimulated a significant increase in matrix metalloproteinase-2 (MMP-2) activity in melanocyte supernatants. Narrow-band UVB-irradiation-induced migration of melanocytes was significantly annihilated by the addition of p125(FAK) inhibitor (herbimycin-A) or MMP-2 inhibitor (GM6001). These results suggest that p125(FAK) and MMP-2 activity play important roles in narrow-band UVB-induced migration of melanocytes. Our results provide a theoretical basis for the effectiveness of narrow-band UVB irradiation in treating vitiligo.

The purpose of this study was to clarify the relationship between the cellular and humoral immune components in the pathogenesis of vitiligo vulgaris. By using cytokines as indicators of peripheral mononuclear cell (MNC) function, we compared the effects of phytohemagglutinin (PHA) and purified IgG on MNCs derived from patients suffering from active vitiligo with those from normal controls. The results revealed (i) a significant increase in spontaneous production of IL-6 and IL-8 in patients; (ii) PHA, purified IgG from patients (IgG-anti-MC), or IgG from normal controls (N-IgG) induced a significant increase in IL-6 but diminished GM-CSF, TNF-alpha, and IFN-gamma release in patients; and (iii) IgG-anti-MC brought about a significantly higher stimulatory effect on IL-1beta and IFN-gamma production than N-IgG in normal controls. Immunologically, IL-6 can enhance melanocyte ICAM-1 expression, which may increase leukocyte-melanocyte attachment and cause melanocyte damage in vitiligo. A decrease in GM-CSF (an intrinsic growth factor for melanocyte) production may retard recovery from vitiligo by checking the proliferation of surviving melanocytes. A significant decrease in TNF-alpha and IFN-gamma production may partially explain the reduced inflammatory reaction in vitiliginous lesions. That IgG-anti-MC stimulates an increase in IL-1beta and IFN-gamma production in controls suggests that IgG-anti-MC may play a role in melanocyte destruction mediated by monocytes.

Psoriasis, which is regarded as a T-cell-mediated chronic inflammatory skin disease, is characterized by hyperproliferation and poor differentiation of epidermal keratinocytes. In this study, we aimed to determine the in vivo effect of a potentially probiotic strain, Lactobacillus pentosus GMNL-77, in imiquimod-induced epidermal hyperplasia and psoriasis-like skin inflammation in BALB/c mice. Oral administration of L. pentosus GMNL-77 significantly decreased erythematous scaling lesions. Real-time polymerase chain reaction showed that treatment with L. pentosus GMNL-77 significantly decreased the mRNA levels of proinflammatory cytokines, including tumor necrosis factor-alpha, interleukin (IL)-6, and the IL-23/IL-17A axis-associated cytokines (IL-23, IL-17A/F, and IL-22) in the skin of imiquimod-treated mice. In addition, we found that L. pentosus GMNL-77 decreased the spleen weights of the imiquimod-treated group and reduced the numbers of IL-17- and IL-22-producing CD4 T cells in the spleen. In conclusion, the present study provides insight into the potential use of L. pentosus GMNL-77 in the future treatment of psoriasis.

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Terpinen-4-ol, a monoterpene component of the essential oils of several aromatic plants, exhibits antitumor effects. In this study, the antitumor effects of terpinen-4-ol and the cellular and molecular mechanisms responsible for it were evaluated and studied, respectively on human nonsmall cell lung cancer (NSCLC) cells. Our results indicated that terpinen-4-ol elicited a dose-dependent cytotoxic effect, as determined by MTT assay. Increased sub-G1 population and annexin-V binding, activation of caspases 9 and 3, cleavage of poly(ADPribose) polymerase (PARP), and a decrease of mitochondrial membrane potential (MMP) indicated involvement of the mitochondrial apoptotic pathway in terpinen-4-ol-treated A549 and CL1-0 cells. Elevation of the Bax/Bcl-2 ratio and a decrease in IAP family proteins XIAP and survivin were also observed following terpinen-4-ol treatment. Notably, terpinen-4-ol was able to increase p53 levels in A549 and CL1-0 cells. Diminution of p53 by RNA interference induced necrosis instead of apoptosis in A549 cells following terpinen-4-ol treatment, indicating that terpinen-4-ol-elicited apoptosis is p53-dependent. Moreover, intratumoral administration of terpinen-4-ol significantly suppressed the growth of s.c. A549 xenografts by inducing apoptosis, as confirmed by TUNEL assay. Collectively, these data provide insight into the molecular mechanisms underlying terpinen-4-ol-induced apoptosis in NSCLC cells, rendering this compound a potential anticancer drug for NSCLC.

A one-pot synthesis of ortho-arylated 9-(pyridin-2-yl)-9H-carbazoles via C–H bond activation is presented. Silver nitrate and tert-butyl alcohol were found to be the best oxidant and solvent for the process, respectively. The product yields are from modest to excellent, and the reaction showed sufficient functional group tolerance. p-Benzoquinone served as an important ligand for the transmetalation and reductive elimination steps in the catalytic process. The key intermediate of the reaction, a 9-(pyridin-2-yl)-9H-carbazole palladacycle, was isolated, and its structure was unequivocally confirmed by X-ray crystallography. No kinetic isotope effect (k H/k D = 1.00 ± 0.17) for the C–H bond activation step was observed. In addition, a Hammett experiment gave a negative ρ value, −2.16 ± 0.02. The directing group, pyridinyl, was demonstrated to be a removable functional group. Finally, a rational catalytic mechanism is presented on the basis of all experimental evidence.

Segmental vitiligo (SV) is a special form of vitiligo occurring in a dermatomal distribution, and an abnormality involving the sympathetic nerves supplying the affected dermatome is known to underlie this disorder. Previously, we have shown that SV is associated with an abnormal increase in cutaneous blood flow and adrenoceptor responses in the affected areas. Since SV is resistant to conventional forms of therapy, its management represents a challenge for dermatologists. Low energy helium-neon lasers (He-Ne laser, wavelength 632.8 nm) have been employed as a therapeutic instrument in many clinical situations, including vitiligo management and repair of nerve injury. The purpose of this study was to evaluate the effectiveness and safety of He-Ne lasers in treating SV, and determine their effects on the repair of sympathetic nerve dysfunction. Forty patients with stable-stage SV on the head and/or neck were enrolled in this study. He-Ne laser irradiation was administered locally at 3.0 J/cm2 with point stimulation once or twice weekly. Cutaneous microcirculatory assessments in six SV patients were performed using a laser Doppler flowmeter. The sympathetic adrenoceptor response of cutaneous microcirculation was determined by measuring cutaneous blood flow before, during and after iontophoresis with sympathomimetic drugs (phenylephrine, clonidine and propranolol). All measurements of microcirculation obtained at SV lesions were simultaneously compared with contralateral normal skin, both before and after He-Ne laser treatment. After an average of 17 treatment sessions, initial repigmentation was noticed in the majority of patients. Marked repigmentation (> 50%) was observed in 60% of patients with successive treatments. Cutaneous blood flow was significantly higher at SV lesions compared with contralateral skin, but this was normalized after He-Ne laser treatment. In addition, the abnormal decrease in cutaneous blood flow in response to clonidine was improved by He-Ne laser therapy. Our study showed that He-Ne laser therapy is an effective treatment for SV by normalizing dysfunctions of cutaneous blood flow and adrenoceptor responses in SV patients. Thus, the beneficial effects of He-Ne laser therapy may be mediated in part by a reparative effect on sympathetic nerve dysfunction.